Research IndicatorsGraph generated 27 February 2015 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 27 February, 2015 using data from PubMed, MeSH and CancerIndex
Specific Cancers (1)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
Search the Epigenomics database and view relevant gene tracks of samples.
Latest Publications: FADD (cancer-related)
BACKGROUND: 11q13 region is a frequently amplified locus in human malignancies. Among the genes located in this region, FADD is one of the alleged driving genes. Because amplification is not generally confined to a single gene and amplified genes may not show increased expression, we need to evaluate clinical significance of changes occurring in 11q13 region to understand their roles in carcinogenesis. Therefore, we screened expressions of FADD and closely located genes (PPFIA1 and TMEM16A) and evaluated the expressions to find clinical significance in invasive ductal carcinoma of the breast.
METHODS: Ninety-eight cases of invasive ductal carcinoma of the breast were collected. Using archival tissues resected from the cases, we built a tissue microarray and used it in immunohistochemistry. We evaluated the association of FADD, PPFIA1, and TMEM16A expression scores with clinicopathological parameters, including disease-free survival.
RESULTS: FADD expression was associated with T stage (P=0.046). The combined score of FADD, PPFIA1, and TMEM16A gene expressions was associated with perineural invasion (P=0.022). Although individual gene expressions of TMEM16A, FADD, and PPFIA1 failed to show significant association with disease-free survival, combined gene expression scores did show association with disease-free survival (P=0.034).
CONCLUSIONS: FADD, TMEM16A, and PPFIA1 gene expressions as a whole were associated with disease-free survival in breast cancer.
Ham S, Kim KH, Kwon TH, et al.Luteolin induces intrinsic apoptosis via inhibition of E6/E7 oncogenes and activation of extrinsic and intrinsic signaling pathways in HPV-18-associated cells.
Oncol Rep. 2014; 31(6):2683-91 [PubMed
] Related Publications
Luteolin, a flavonoid extracted from a number of plants with recognized anticancer, anti-inflammatory and anti-oxidative activities, inhibits angiogenic processes and modulates multidrug resistance. However, the efficacy and mechanisms of action of this flavonoid agent are still undergoing study. In order to elucidate whether luteolin exhibits an anticancer effect in cervical cancer cells, HeLa cells were incubated with luteolin and apoptosis was assessed by observing nuclear morphological changes, and performing Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. Cell cycle analysis, western blotting, RT-PCR and mitochondrial membrane potential measurements were also carried out. Luteolin showed a significant dose-dependent cytotoxic effect only in human papillomavirus (HPV)-positive cervical cancer cells, when compared to its effect on HPV-negative cervical cancer C33A cells. Expression levels of human papilloma virus E6 and E7 oncogenes were suppressed, those of related factors pRb and p53 were recovered and E2F5 was increased by luteolin treatment. Furthermore, luteolin enhanced the expression of death receptors and death receptor downstream factors such as Fas/FasL, DR5/TRAIL and FADD in HeLa cells, and activated caspase cascades. In particular, luteolin enhanced the activity of caspase-3 and -8 in a dose-dependent manner. Activation of caspase-3 induced caspase-8 activity and vice versa. Luteolin also induced mitochondrial membrane potential collapse and cytochrome c release, and inhibited Bcl-2 and Bcl-xL expression. In conclusion, luteolin exerts anticarcinogenic activity through inhibition of E6 and E7 expression and cross-activation of caspase-3 and -8. Taken together, these results suggest that luteolin induces inactivation of HPV-18 oncogene expression and apoptosis by activating the intrinsic and extrinsic pathways.
BACKGROUND: MUC16 (CA125) is a large transmembrane mucin protein (> 200 kDa) aberrantly expressed in approximately 80% of human epithelial ovarian cancers (EOC). MUC16 expression in EOC cells is associated with increased tumorigenesis and inhibiton of genotoxic drug-induced apoptosis. However, the mechanism by which MUC16 mediates these effects is unknown. In the present study, we investigated the mechanisms by which MUC16 attenuates TRAIL-induced apoptosis.
METHODS: MUC16 expression was down-regulated by stably expressing an anti-MUC16 single-chain antibody (scFv) targeted to the endoplasmic reticulum (ER), which prevents cell surface localization of MUC16 in OVCAR3 cells. We also generated a MUC16 C-terminal domain (MUC16CTD) construct that was stably expressed in MUC16 negative SKOV3 cells.
RESULTS: We show that MUC16 attenuates apoptosis, activation of caspase-8 and mitochondria activation in EOC cells in response to TRAIL. MUC16 decreases TRAIL receptor R2 (DR5) expression and inhibits pro-caspase-8 activation at the death-inducing signaling complex (DISC). MUC16CTD expression is sufficient to attenuate the TRAIL signaling cascade. MUC16 knockdown decreases caspase-8 inhibitor cFLIP mRNA levels, increases cFLIP degradation, and consequently increases TRAIL-induced apoptosis. Down-regulation of cFLIP following treatment of MUC16-expressing OVCAR3 cells with cFLIP siRNA also increases TRAIL-induced apoptosis.
CONCLUSIONS: These findings indicate that MUC16 protects EOC cells against TRAIL-induced apoptosis through multiple mechanisms including the blockade of TRAIL R2 expression and the regulation of cFLIP expression at both the transcriptional and the protein level.
Min KJ, Seo BR, Bae YC, et al.Antipsychotic agent thioridazine sensitizes renal carcinoma Caki cells to TRAIL-induced apoptosis through reactive oxygen species-mediated inhibition of Akt signaling and downregulation of Mcl-1 and c-FLIP(L).
Cell Death Dis. 2014; 5:e1063 [PubMed
] Free Access to Full Article Related Publications
Thioridazine has been known as an antipsychotic agent, but it also has anticancer activity. However, the effect of thioridazine on tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) sensitization has not yet been studied. Here, we investigated the ability of thioridazine to sensitize TRAIL-mediated apoptosis. Combined treatment with thioridazine and TRAIL markedly induced apoptosis in various human carcinoma cells, including renal carcinoma (Caki, ACHN, and A498), breast carcinoma (MDA-MB231), and glioma (U251MG) cells, but not in normal mouse kidney cells (TMCK-1) and human normal mesangial cells. We found that thioridazine downregulated c-FLIP(L) and Mcl-1 expression at the post-translational level via an increase in proteasome activity. The overexpression of c-FLIP(L) and Mcl-1 overcame thioridazine plus TRAIL-induced apoptosis. We further observed that thioridazine inhibited the Akt signaling pathway. In contrast, although other phosphatidylinositol-3-kinase/Akt inhibitors (LY294002 and wortmannin) sensitized TRAIL-mediated apoptosis, c-FLIP(L) and Mcl-1 expressions were not altered. Furthermore, thioridazine increased the production of reactive oxygen species (ROS) in Caki cells, and ROS scavengers (N-acetylcysteine, glutathione ethyl ester, and trolox) inhibited thioridazine plus TRAIL-induced apoptosis, as well as Akt inhibition and the downregulation of c-FLIP(L) and Mcl-1. Collectively, our study demonstrates that thioridazine enhances TRAIL-mediated apoptosis via the ROS-mediated inhibition of Akt signaling and the downregulation of c-FLIP(L) and Mcl-1 at the post-translational level.
Some cases of breast cancer are composed of clones of hormonal-independent growing cells, which do not respond to therapy. In the present study, the effect of Benzene-Poly-Carboxylic Acid Complex (BP-C1) on growth of human breast-cancer cells was tested. BP-C1 is a novel anti-cancer complex of benzene-poly-carboxylic acids with a very low concentration of cis-diammineplatinum (II) dichloride. Human breast cancer cells, MCF-7 and T47D, were used. Cell viability was detected by XTT assay and apoptosis was detected by Flow Cytometry and by annexin V/FITC/PI assay. Caspases were detected by western blot analysis and gene expression was measured by using the Applied Biosystems® TaqMan® Array Plates. The results showed that exposure of the cells to BP-C1 for 48 h, significantly (P<0.001) reduced cell viability, induced apoptosis and activated caspase 8 and caspace 9. Moreover, gene expression experiments indicated that BP-C1 increased the expression of pro-apoptotic genes (CASP8AP1, TNFRSF21, NFkB2, FADD, BCL10 and CASP8) and lowered the level of mRNA transcripts of inhibitory apoptotic genes (BCL2L11, BCL2L2 and XIAP. These findings may lead to the development of new therapeutic strategies for treatment of human cancer using BP-C1 analog.
Ribeiro IP, Marques F, Caramelo F, et al.Genetic imbalances detected by multiplex ligation-dependent probe amplification in a cohort of patients with oral squamous cell carcinoma-the first step towards clinical personalized medicine.
Tumour Biol. 2014; 35(5):4687-95 [PubMed
] Related Publications
Oral tumors are a growing health problem worldwide; thus, it is mandatory to establish genetic markers in order to improve diagnosis and early detection of tumors, control relapses and, ultimately, delineate individualized therapies. This study was the first to evaluate and discuss the clinical applicability of a multiplex ligation-dependent probe amplification (MLPA) probe panel directed to head and neck cancer. Thirty primary oral squamous cell tumors were analyzed using the P428 MLPA probe panel. We detected genetic imbalances in 26 patients and observed a consistent pattern of distribution of genetic alterations in terms of losses and gains for some chromosomes, particularly for chromosomes 3, 8, and 11. Regarding the latter, some specific genes were highlighted due to frequent losses of genetic material--RARB, FHIT, CSMD1, GATA4, and MTUS1--and others due to gains--MCCC1, MYC, WISP1, PTK2, CCND1, FGF4, FADD, and CTTN. We also verified that the gains of MYC and WISP1 genes seem to suggest higher propensity of tumors localized in the floor of the mouth. This study proved the value of this MLPA probe panel for a first-tier analysis of oral tumors. The probemix was developed to include target regions that have been already shown to be of diagnostic/prognostic relevance for oral tumors. Furthermore, this study emphasized several of those specific genetic targets, suggesting its importance to oral tumor development, to predict patients' outcomes, and also to guide the development of novel molecular therapies.
BACKGROUND: Parthenolide (PTL) is a sesquiterpene lactone which can induce apoptosis in cancer cells and eradicate cancer stem cells such as leukemia stem cells, prostate tumor-initiating cells and so on. However, the mechanism remains largely unclear.
METHODS: Lung cancer cells were treated with parthenolide and the cell lysates were prepared to detect the given proteins by Western Blot analysis, and the cell survival was assayed by SRB and MTT assay. Cell cycle was evaluated by DNA flow cytometry analysis. TNFRSF10B, PMAIP1, ATF4 and DDIT3 genes were knocked down by siRNA technique. Apoptosis was evaluated by using Annexin V-FITC/PI staining and flow cytometry analysis.
RESULTS: Parthenolide (PTL) induces apoptosis and cell cycle arrest in human lung cancer cells. Moreover, PTL treatment in NSCLC cells increases expression of TNFRSF10B/DR5 and PMAIP1/NOXA. Silencing of TNFRSF10B or PMAIP1 or overexpression of CFLAR /c-FLIP (long form) could protect cells from PTL-induced apoptosis. Furthermore, PTL could increase the levels of endoplasmic reticulum stress hallmarks such as ERN1, HSPA5, p-EIF2A, ATF4 and DDIT3. Knockdown of ATF4 and DDIT3 abrogated PTL-induced apoptosis, which suggested that PTL induced apoptosis in NSCLC cells through activation of endoplasmic reticulum stress pathway. More importantly, we found that ATF4, DDIT3, TNFRSF10B and PMAIP1 were up-regulated more intensively, while CFLAR and MCL1 were down-regulated more dramatically by PTL in A549/shCDH1 cells than that in control cells, suggesting that PTL preferred to kill cancer stem cell-like cells by activating more intensive ER stress response in cancer stem cell-like cells.
CONCLUSION: We showed that parthenolide not only triggered extrinsic apoptosis by up-regulating TNFRSF10B and down-regulating CFLAR, but also induced intrinsic apoptosis through increasing the expression of PMAIP1 and decreasing the level of MCL1 in NSCLC cells. In addition, parthenolide triggered stronger ER stress response in cancer stem cell-like cells which leads to its preference in apoptotic induction. In summary, PTL induces apoptosis in NSCLC cells by activating endoplasmic reticulum stress response.
Qin Y, Chu B, Gong W, et al.Inhibitory effects of deleted in liver cancer 1 gene on gallbladder cancer growth through induction of cell cycle arrest and apoptosis.
J Gastroenterol Hepatol. 2014; 29(5):964-72 [PubMed
] Related Publications
BACKGROUND AND AIM: The biological function of tumor suppressor deleted in liver cancer 1 (DLC1) has been investigated in several types of human cancer, but its role in gallbladder cancer (GBC) is yet to be determined. In this research, we conducted in vitro and in vivo analysis to evaluate the inhibitory activities of DLC1 gene against GBC growth.
METHODS: DLC1 expression in GBC tissues and cell lines was examined by immunohistochemical staining, reverse transcription polymerase chain reaction, and Western blot assay. The in vitro and in vivo effects of ectopic DLC1 expression on cell growth were evaluated. In addition, the effects of ectopic DLC1 expression on cell cycle, apoptosis, and migration were also evaluated. The expressions of cell cycle-related and apoptosis-related proteins were examined.
RESULTS: The downregulation of DLC1 expression was a common event in GBC tissues and cell lines. Restoration of DLC1 expression in GBC-SD and NOZ cells significantly reduced cell proliferation, migration in vitro, and the ability of these cells to form tumors in vivo. Restoration of DLC1 expression arrested GBC-SD and NOZ cells in G0/G1 phase through inducing p21 in a p53-independent manner. In addition, restoration of DLC1 expression induced extrinsic and intrinsic apoptotic pathway through promoting the expressions of Fas L/FADD, Bax, cytochrome c, cleaved caspase-8, -9, -3, and cleaved poly-(ADP-ribose) polymerase and suppressing bcl-2 expression in GBC-SD and NOZ cells.
CONCLUSIONS: Our findings suggested that dysregulated expression of DLC1 is involved in proliferation and invasion of GBC cells and may serve as a potential therapeutic target.
Yamada N, Noguchi S, Kumazaki M, et al.Epigenetic regulation of microRNA-128a expression contributes to the apoptosis-resistance of human T-cell leukaemia jurkat cells by modulating expression of fas-associated protein with death domain (FADD).
Biochim Biophys Acta. 2014; 1843(3):590-602 [PubMed
] Related Publications
Increased expression of miR-128a is often observed in acute lymphoblastic leukaemia (ALL) compared with its expression in acute myeloid leukaemia (AML). The objective of this study was to investigate the role of miR-128a, especially that in the Fas-signalling pathway, in T-cell leukaemia cells. The role of miR-128a in Fas-mediated apoptosis was examined by using Fas-activating antibody (CH-11)-susceptible Jurkat cells and -resistant Jurkat/R cells. Whereas ectopic expression of miR-128a conferred Fas-resistance on Jurkat cells by directly targeting Fas-associated protein with death domain (FADD), antagonizing miR-128a expression sensitized Jurkat/R cells to the Fas-mediated apoptosis through derepression of FADD expression. Myeloid leukaemia HL60 and K562 cells were also CH-11-resistant, sharing a similar resistant mechanism with Jurkat/R cells. Furthermore, CH-11 induced demethylation of the promoter region of miR-128a with resultant up-regulation of miR-128a expression in Jurkat/R cells, which was shown to be a mechanism for the resistance ofJurkat/R cells to Fas-mediated apoptosis. Our results indicate that the induction of miR-128a expression by DNA demethylation is a novel mechanism of resistance to Fas-mediated apoptosis.
Belt EJ, Stockmann HB, Delis-van Diemen PM, et al.Expression of apoptosis regulating proteins identifies stage II and III colon cancer patients with high risk of recurrence.
J Surg Oncol. 2014; 109(3):255-65 [PubMed
] Related Publications
BACKGROUND AND OBJECTIVES: Deregulation of apoptosis related genes may be associated with poor outcome in cancer. Aim of the present study was to investigate the prognostic role of expression levels of apoptosis related proteins in stage II and III colon cancer.
METHODS: From tumor samples of 386 stage II and III colon cancer patients, DNA was isolated and tissue microarrays were constructed. Expression of Bcl-2, Bcl-X, BAX, XIAP, Fas, FasL and c-FLIP was evaluated and PCR-based microsatellite instability analysis was performed.
RESULTS: High FasL expressing tumors were associated with high disease recurrence rates in stage II colon cancer patients overall, as was low Bcl-X expression in microsatellite stable stage II patients. In stage II patients, a multivariable model based on FasL and Bcl-XL expression revealed a significant association with disease free survival (DFS). In stage III colon cancer patients, low Bcl-2, low BAX and low Fas expression levels were associated with worse outcome. In these patients a multivariable model based on angioinvasion and Bcl-2, Fas and FasL expression was significantly associated with DFS.
CONCLUSIONS: Stage II patients with low Bcl-X and high FasL protein expression levels and stage III patients with low Fas, high FasL and low Bcl-2 expression could be considered as high risk for disease recurrence.
Context-specific molecular vulnerabilities that arise during tumor evolution represent an attractive intervention target class. However, the frequency and diversity of somatic lesions detected among lung tumors can confound efforts to identify these targets. To confront this challenge, we have applied parallel screening of chemical and genetic perturbations within a panel of molecularly annotated NSCLC lines to identify intervention opportunities tightly linked to molecular response indicators predictive of target sensitivity. Anchoring this analysis on a matched tumor/normal cell model from a lung adenocarcinoma patient identified three distinct target/response-indicator pairings that are represented with significant frequencies (6%-16%) in the patient population. These include NLRP3 mutation/inflammasome activation-dependent FLIP addiction, co-occurring KRAS and LKB1 mutation-driven COPI addiction, and selective sensitivity to a synthetic indolotriazine that is specified by a seven-gene expression signature. Target efficacies were validated in vivo, and mechanism-of-action studies informed generalizable principles underpinning cancer cell biology.
Ji YB, Ji CF, Yue LStudy on human promyelocytic leukemia HL-60 cells apoptosis induced by fucosterol.
Biomed Mater Eng. 2014; 24(1):845-51 [PubMed
] Related Publications
In this study, we investigated the effect of fucosterol on HL-60 and the molecular mechanism. HL-60 Cells were treated with fucosterol, and 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) method was used to study fucosterol anti-tumor activity. Morphology of HL-60 cells was observed. Flow cytometry (FCM) was employed to detect the cell cycle. Laser scanning confocal microscope (LSCM) was used to analyze mitochondrial membrane potential (MMP) and the expressions of Fas, FasL, Fadd and Caspase-8. Western blot was performed to analyze the expressions of Cyt-C, Pro-Caspase-9 and Pro-Caspase-3. Caspase activity kits were used to determine the activity of Caspase-9, Caspase-8 and Caspase-3. The results showed fucosterol could inhibit the growth of HL-60 cells, and the cell cycle was arrested at G2/M phase. HL-60 cells showed obvious apoptosis morphology. After being treated with fucosterol for 24 h, HL-60 cells decreased MMP, induced Cyt-C release and Caspase-9, Caspase-3 activation. Fucosterol also increased the protein expression of Fas, FasL, Fadd and Caspase-8. Moreover, the activity of Caspase-9, Caspase-8 and Caspase-3 was increased significantly. In conclusion, Fucosterol can induce HL-60 cells apoptosis, suggesting that it may be a potent agent for cancer prevention and treatment.
Chromik J, Safferthal C, Serve H, Fulda SSmac mimetic primes apoptosis-resistant acute myeloid leukaemia cells for cytarabine-induced cell death by triggering necroptosis.
Cancer Lett. 2014; 344(1):101-9 [PubMed
] Related Publications
The prognosis for patients with acute myeloid leukaemia (AML) is still poor, thus calling for novel treatment strategies. Here, we report that the small-molecule Smac mimetic BV6, which antagonizes Inhibitor of Apoptosis (IAP) proteins, acts in concert with cytarabine (AraC) to trigger cell death in AML cells in a highly synergistic manner (combination index 0.02-0.27). Similarly, BV6 cooperates with AraC to trigger cell death in primary AML samples, underscoring the clinical relevance of our findings. Molecular studies reveal that the TNFα-blocking antibody Enbrel significantly reduces BV6/AraC-induced cell death, demonstrating that an autocrine/paracrine TNFα loop mediates cell death. Furthermore, BV6 and AraC synergize to induce loss of mitochondrial membrane potential, caspase activation and DNA fragmentation, consistent with apoptotic cell death. Nevertheless, the caspase inhibitor zVAD.fmk fails to protect against BV6/AraC-induced cell death. Intriguingly, this cell death upon caspase inhibition is significantly reduced by pharmacological inhibition of two key components of necroptosis signaling, i.e. by RIP1 kinase inhibitor Necrostatin-1 or MLKL inhibitor NSA. Thus, BV6 sensitizes AML cells to AraC-induced cell death and overcomes apoptosis resistance by triggering necroptosis as alternative form of cell death. These findings have important implications for Smac mimetic-based strategies to bypass apoptosis resistance of AML.
Jin CY, Yu HY, Park C, et al.Oleifolioside B-mediated autophagy promotes apoptosis in A549 human non-small cell lung cancer cells.
Int J Oncol. 2013; 43(6):1943-50 [PubMed
] Related Publications
The biochemical mechanisms of cell death by oleifolioside B (OB), a cycloartane-type triterpene glycoside isolated from Dendropanax morbifera Leveille, were investigated in A549 human lung carcinoma cells. Our data indicated that exposure to OB led to caspase activation and typical features of apoptosis; however, apoptotic cell death was not prevented by z-VAD-fmk, a pan-caspase inhibitor, demonstrating that OB-induced apoptosis was independent of caspase activation. Subsequently, we found that OB increased autophagy, as indicated by an increase in monodansylcadaverine fluorescent dye-labeled autophagosome formation and in the levels of the autophagic form of microtubule-associated protein 1 light chain 3 and Atg3, an autophagy-specific gene, which is associated with inhibiting phospho-nuclear factor erythroid 2-related factor 2 (Nrf2) expression. However, pretreatment with bafilomycin A1, an autophagy inhibitor, attenuated OB-induced apoptosis and dephosphorylation of Nrf2. The data suggest that OB-induced autophagy functions as a death mechanism in A549 cells and OB has potential as a novel anticancer agent capable of targeting apoptotic and autophagic cell death and the Nrf2 signaling pathway.
The expression of apoptosis genes in a commercial pre-designed low-density array from Applied Biosystems was evaluated in two human brain cancer cell models, LN-18 and Daoy (HTB-186™) in comparison to the reference human primary endothelial cells under basic conditions. Analysis of the gene expression in the cancer cell lines compared to the normal control revealed features reflecting anti-apoptotic and inflammatory characteristics of the former. There was an overall downregulation of apoptosis-stimulating genes in both cancer cell lines, along with an upregulation of certain apoptosis inhibitors. A number of genes demonstrated statistically significant changes in their expressions, including BAX (BCL2-associated X protein); the CARD4/NLR family, CARD domain containing 4; CASP10 (caspase 10, apoptosis-related cysteine peptidase); DAP1 (death-associated protein kinase 1), and BIRC5 (baculoviral IAP repeat-containing 5). Anti-apoptotic potential in both cell lines was demonstrated by changes in the Bax:Bcl-2 ratio and downregulation of the APAF1 gene in LN18 cells. There was also significant downregulation of extrinsic signals and the TNF/FADD/inflammatory cascade, and upregulation of caspase inhibitors (IAPs). These results provided a novel molecular characterization of important human cancer cell lines, which might provide a useful research tool for investigating the experimental model of the CNS cell.
In the lymph node (LN) environment, chronic lymphocytic leukemia (CLL) cells display increased NF-κB activity compared with peripheral blood CLL cells, which contributes to chemoresistance. Antagonists of cellular inhibitor of apoptosis proteins (cIAPs) can induce apoptosis in various cancer cells in a tumor necrosis factor-α (TNFα)-dependent manner and are in preclinical development. Smac-mimetics promote degradation of cIAP1 and cIAP2, which results in TNFR-mediated apoptosis via formation of a ripoptosome complex, comprising RIPK1, Fas-associated protein with death domain, FLICE-like inhibitory protein and caspase-8. CD40 stimulation of CLL cells in vitro is used as a model to mimic the LN microenvironment and results in NF-κB activation and TNFα production. In this study, we investigated the response of CLL cells to smac-mimetics in the context of CD40 stimulation. We found that treatment with smac-mimetics results in cIAP1 and cIAP2 degradation, yet although TNFα is produced, this did not induce apoptosis. Despite the presence of all components, the ripoptosome complex did not form upon smac-mimetic treatment in CLL cells. Thus, CLL cells seem to possess aberrant upstream NF-κB regulation that prevents ripoptosome formation upon IAP degradation. Unraveling the exact molecular mechanisms of disturbed ripoptosome formation may offer novel targets for treatment in CLL.
The receptor-interacting protein kinase 3 (RIP3/RIPK3) has emerged as a critical regulator of programmed necrosis/necroptosis, an inflammatory form of cell death with important functions in pathogen-induced and sterile inflammation. RIP3 activation is tightly regulated by phosphorylation, ubiquitination, and caspase-mediated cleavage. These post-translational modifications coordinately regulate the assembly of a macromolecular signaling complex termed the necrosome. Recently, several reports indicate that RIP3 can promote inflammation independent of its pronecrotic activity. Here, we review our current understanding of the mechanisms that drive RIP3-dependent necrosis and its role in different inflammatory diseases.
The role of Pokemon (POK erythroid myeloid ontogenic actor), a recently identified POK transcription factor with proto-oncogenic activity, in hepatocellular carcinogenesis has only been assessed by a few studies. Our previous study revealed that Pokemon is overexpressed in hepatocellular carcinomas (HCC) and promotes HCC cell proliferation and migration via an AKT- and ERK- dependent manner. In the present study, we used the TUNEL assay and FACS analysis to demonstrate that oxaliplatin induced apoptosis was significantly increased in cells with silenced Pokemon. Western blots showed that p53 expression and phosphorylation were significantly increased in Pokemon defective cells, thereby initiating the mitochondria-mediated and death receptor-mediated apoptotic pathways. In the mitochondria-mediated pathway, expression of pro-apoptotic Bcl-2 family members (including Bad, Bid, Bim and Puma) as well as AIF was increased and decreasing the mitochondrial membrane potential resulted in cytochrome C released from mitochondrial in HepG2 si-Pokemon cells. In addition, upon oxaliplatin treatment of Pokemon-silenced cells, the FAS receptor, FADD and their downstream targets caspase-10 and caspase-8 were activated, causing increased release of caspase-8 active fragments p18 and p10. Increased activated caspase-8-mediated cleavage and activation of downstream effector caspases such as caspase-9 and caspase-3 was observed in HepG2 si-Pokemon cells as compared to control. Therefore, Pokemon might serve as an important mediator of crosstalk between intrinsic and extrinsic apoptotic pathways in HCC cells. Moreover, our findings suggest that Pokemon could be an attractive therapeutic target gene for human cancer therapy.
We evaluated effect of dual gene silencing of Hsp27 and c-FLIP in doxazosin-induced apoptosis of PC-3 cell. After transfection using Hsp27 and c-FLIP siRNA mixture (dual silencing), doxazosin treatment was done at the concentrations of 1, 10, and 25 μ M. We checked apoptosis of PC-3 cells with and TUNEL staining. We also checked interaction between Hsp27 and C-FLIP in the process of apoptosis inhibition. Spontaneous apoptotic index was 5% under single gene silencing of Hsp27 and c-FLIP and 7% under dual silencing of Hsp27 and c-FLIP. When doxazosin treatment was added, apoptotic indices increased in a dose-dependent manner (1, 10, and 25 μ M): nonsilencing 10, 27, and 52%; Hsp27-silencing: 14, 35, and 68%; c-FLIP silencing: 21, 46, and 78%; dual silencing: 38, 76, and 92%. While c-FLIP gene expression decreased in Hsp27- silenced cells, Hsp27 gene expression showed markedly decreased pattern in the cells of c-FLIP silencing. The knockout of c-FLIP and Hsp27 genes together enhances apoptosis even under 1 μ M, rather than low concentration, of doxazosin in PC-3 cells. This finding suggests a new strategy of multiple knockout of antiapoptotic and survival factors in the treatment of late-stage prostate cancer refractory to conventional therapy.
Kiyota M, Kuroda J, Yamamoto-Sugitani M, et al.FTY720 induces apoptosis of chronic myelogenous leukemia cells via dual activation of BIM and BID and overcomes various types of resistance to tyrosine kinase inhibitors.
Apoptosis. 2013; 18(11):1437-46 [PubMed
] Related Publications
PP2A activator FTY720 has been shown to possess the anti-leukemic activity for chronic myelogenous leukemia (CML), however, the cell killing mechanism underlying its anti-leukemic activity has remained to be verified. We investigated the precise mechanisms underlying the apoptosis induction by FTY720, especially focusing on the roles of BH3-only proteins, and the therapeutic potency of FTY720 for CML. Enforced expression of either BCL2 or the dominant-negative protein of FADD (FADD.DN) partly protected CML cells from apoptosis by FTY720, indicating the involvement of both cell extrinsic and intrinsic apoptosis pathways. FTY720 activates pro-apoptotic BH3-only proteins: BIM, which is essential for apoptosis by BCR-ABL1 tyrosine kinase inhibitors (TKIs), and BID, which accelerates the extrinsic apoptosis pathway. Gene knockdown of either BIM or BID partly protected K562 cells from apoptosis by FTY720, but the extent of cell protection was not as much as that by overexpression of either BCL2 or FADD.DN. Moreover, knockdown of both BIM and BID did not provide additional protection compared with knockdown of only BIM or BID, indicating that BIM and BID complement each other in apoptosis by FTY720, especially when either is functionally impaired. FTY720 can overcome TKI resistance caused by ABL kinase domain mutations, dysfunction of BIM resulting from gene deletion polymorphism, and galectin-3 overexpression. In addition, ABT-263, a BH3-mimetic, significantly augmented cell death induction by FTY720 both in TKI-sensitive and -resistant leukemic cells. These results provide the rationale that FTY720, with its unique effects on BIM and BID, could lead to new therapeutic strategies for CML.
Zhou J, Song S, He S, et al.Silencing of decoy receptor 3 (DcR3) expression by siRNA in pancreatic carcinoma cells induces Fas ligand-mediated apoptosis in vitro and in vivo.
Int J Mol Med. 2013; 32(3):653-60 [PubMed
] Related Publications
Decoy receptor 3 (DcR3) is abundantly expressed in human tumors and protects cells from a wide range of apoptotic stimuli. In this study, we demonstrate that DcR3 is overexpressed in pancreatic carcinoma cells, and that the pancreatic carcinoma cell lines, Panc-1 and SW1990, are resistant to Fas ligand (FasL)-mediated apoptosis. To further define the function of DcR3 in cell growth and apoptosis, we used small interfering RNA (siRNA) to knockdown the expression of the DcR3 gene in Panc-1 and SW1990 cells. Our results revealed that the silencing of DcR3 expression enhanced the inhibitory effects of FasL and reduced the capabiltiy of the cells for proliferation and colony formation in vitro. In addition, the downregulation of DcR3 modulated the cell apoptotic regulators, Fas-associated death domain (FADD), caspase‑3 and caspase‑8, thus triggering cell apoptosis. Furthermore, the knockdown of DcR3 inhibited the growth of Panc-1 tumor xenografts. Taken together, our findings indicate that DcR3 is important in cancer progression and may be a used as a potential therapeutic target for the gene therapy of pancreatic carcinoma.
He J, Zhang W, Zhou Q, et al.Low-expression of microRNA-107 inhibits cell apoptosis in glioma by upregulation of SALL4.
Int J Biochem Cell Biol. 2013; 45(9):1962-73 [PubMed
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Glioma is the most common highly malignant primary brain tumor. The molecular pathways that result in the pathogenesis of glioma remain elusive. In this study, we found microRNA-107 (miR-107) was downregulated in glioma tissues and cell lines. Our results revealed miR-107 overexpression suppressed cell proliferation in glioma cells, whereas miR-107 knockdown promoted cell growth in MO59K. miR-107 expression induced apoptosis in glioma cells possibly through the increase in Fas (TNFRSF6)-associated via death domain (FADD) expression and activation of caspases-8 and -3/7. Moreover, the activity of caspase-8 in miR-107-overexpressing SHG44 cells was suppressed with FADD knockdown. The tumor growth in nude mice bearing miR-107-overexpressing SHG44 cells was blocked through apoptosis induction. Sal-like 4 (Drosophila) (SALL4) level was reduced upon miR-107 overexpression in glioma cells, and the inverse was observed upon miR-107 knockdown in MO59K. Using a luciferase reporter system, SALL4 3'-UTR-dependent luciferase activity was reduced by miR-107 mimics or increased by an inhibitor of miR-107. In SHG44, SALL4 downregulation triggered growth inhibition and activated FADD-mediated cell apoptosis pathway. The caspase-8 activity in miR-107-overexpressing SHG44 cells was suppressed with SALL4 upregulation. Furthermore, primary glioma tumors with low miR-107 expression show elevated SALL4 level. An obvious inverse correlation was observed between miR-107 expression and SALL4 level in clinical glioma samples. Therefore, our results demonstrate upregulation of miR-107 suppressed glioma cell growth through direct targeting of SALL4, leading to the activation of FADD/caspase-8/caspase-3/7 signaling pathway of cell apoptosis. These data suggest miR-107 is a potential therapeutic target against glioma.
IFN regulatory factor (IRF) 4 is a hematopoietic cell-specific transcription factor that regulates the maturation and differentiation of immune cells. Using an inducible expression system, we found that IRF4 directly induced a specific subset of IFN-stimulated genes (ISGs) in a type I IFN-independent manner in both epithelial and B cell lines. Moreover, Kaposi sarcoma-associated herpesvirus (KSHV)-encoded viral FLICE inhibitory protein (vFLIP) enhances IRF4-mediated gene induction. Coexpression of IRF4 with vFLIP significantly increased ISG60 (IFIT3) and Cig5 (RSAD2) transcription that was dependent on the ability of vFLIP to activate NF-κB. A vFLIP mutant (A57L) defective in NF-κB activation failed to enhance IRF4-mediated ISG induction. Thus, we provide a physiologically relevant mechanism by which viral protein-mediated NF-κB activation modulates specific ISG induction by IRF4. In contrast, IRF4 also acted as a negative regulator of KSHV replication and transcription activator expression after induction of KSHV lytic reactivation in KSHV-positive primary effusion lymphoma cells. Taken together, these results suggest a dual role for IRF4 in regulating ISG induction and KSHV lytic reactivation in primary effusion lymphoma cells.
Liu G, Wang R, Wang Y, et al.Ethacrynic acid oxadiazole analogs induce apoptosis in malignant hematologic cells through downregulation of Mcl-1 and c-FLIP, which was attenuated by GSTP1-1.
Mol Cancer Ther. 2013; 12(9):1837-47 [PubMed
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Ethacrynic acid, a diuretic, inhibits glutathione S-transferase P1-1 (GSTP1-1) activity and induces cell death in malignant cells at high concentrations. To improve ethacrynic acid activity, ethacrynic acid oxadiazole analogs 6s and 6u were synthesized. Although both compounds have greater antiproliferative effects than ethacrynic acid in human HL-60 cells, 6u has a reduced ability to inhibit GSTP1-1 activity. The mechanisms of both 6s- and 6u-induced cell death as well as the role of GSTP1-1 in their actions were studied. Both 6s and 6u equally induced apoptosis in HL-60 cells due to the activation of caspase-3, -9, and -8, which was correlated with the downregulation of antiapoptotic proteins c-FLIP, Mcl-1, and XIAP. The caspase inhibitor Z-VAD-FMK blocked the reduction of XIAP, but not of c-FLIP and Mcl-1, in 6s-treated cells. The reduction of c-FLIP and Mcl-1 by 6s was not blocked by the proteasomal inhibitor MG132, but was correlated with inhibition of the phosphorylation of extracellular signal-regulated kinase (ERK) and eIF4E. Both 6s and 6u decreased the intracellular glutathione (GSH) levels. N-acetylcysteine blocked reduction in the levels of Mcl-1, c-FLIP, and intracellular GSH as well as apoptosis in HL-60 cells treated by either compound. Silencing of GSTP1-1 in K562 cells sensitized, but overexpression of GSTP1-1 in Raji cells blocked, apoptosis induction by either compound. GSH conjugation at the methylene group abrogated the ability of inducing apoptosis. These data suggest that the methylene group plays an important role in the downregulation of c-FLIP and Mcl-1 proteins and apoptosis induction, which is inactivated by GSTP1-1 by forming GSH conjugates.
Atmaca H, Bozkurt E, Uzunoglu S, et al.A diverse induction of apoptosis by trabectedin in MCF-7 (HER2-/ER+) and MDA-MB-453 (HER2+/ER-) breast cancer cells.
Toxicol Lett. 2013; 221(2):128-36 [PubMed
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Trabectedin (Yondelis, ET-743), a semi synthetic tetrahydroisoquinoline alkaloid that was originally derived from the marine tunicate Ecteinascidia turbinata. The objective of this study was to investigate whether trabectedin mediated apoptosis shows any diversity in human breast cancer cell lines with different genotypes. Trabectedin induced cytotoxicity and apoptosis in both breast cancer cells in a time and concentration-dependent manner. The expression levels of the death receptor pathway molecules, TRAIL-R1/DR4, TRAIL-R2/DR5, FAS/TNFRSF6, TNF RI/TNFRSF1A, and FADD were significantly increased by 2.6-, 3.1-, 1.7-, 11.2- and 4.0-fold by trabectedin treatment in MCF-7 cells. However, in MDA-MB-453 cells, the mitochondrial pathway related pro-apoptotic proteins Bax, Bad, Cytochrome c, Smac/DIABLO, and Cleaved Caspase-3 expressions were induced by 4.2-, 3.6-, 4.8-, 4.5-, and 4.4-fold, and the expression levels of anti-apoptotic proteins Bcl-2 and Bcl-XL were reduced by 4.8- and 5.2-fold in MDA-MB-453 cells. Moreover, trabectedin treatment increased the generation of ROS in both breast cancer cells. We have shown that trabectedin causes selective activation of extrinsic and intrinsic apoptotic pathways in two genotypically different breast cancer cells. This preliminary data might guide clinicians to choose appropriate combination agents with trabectedin based on different molecular subtypes of breast cancer.
Pattje WJ, Melchers LJ, Slagter-Menkema L, et al.FADD expression is associated with regional and distant metastasis in squamous cell carcinoma of the head and neck.
Histopathology. 2013; 63(2):263-70 [PubMed
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AIMS: The Fas-associated death domain gene (FADD) is often overexpressed in squamous cell carcinoma of the head and neck (HNSCC), and is considered to be a driver gene in amplification of the chromosomal 11q13.3 region. Amplification of 11q13.3 is associated with increased metastasis in HNSCC and breast cancer. The aim of this study was to investigate the association between FADD protein expression in advanced-stage HNSCC and clinicopathological features and outcome.
METHODS AND RESULTS: Tumour tissues of 177 HNSCC patients uniformly treated with primary surgery and postoperative radiotherapy were collected. FADD expression was assessed on pretreatment tumour biopsies using immunohistochemistry. High FADD expression was detected in 44% of the HNSCC patients. High expression was associated with an increased rate of lymph node metastasis (P = 0.001) and with a shorter distant metastasis-free interval (DMFI) (HR 2.6, 95% CI 1.0-6.7, P = 0.046) when lymph node metastases were present.
CONCLUSIONS: Our data show that an increase in FADD expression is associated with a higher incidence of lymph node metastasis at presentation, and with shorter DMFI when lymph node metastases are present. High FADD expression in the primary tumour could be a useful marker to select patients for systemic treatment strategies that reduce the risk of distant metastases.
Jarmuz-Szymczak M, Pelinska K, Kostrzewska-Poczekaj M, et al.Heterogeneity of 11q13 region rearrangements in laryngeal squamous cell carcinoma analyzed by microarray platforms and fluorescence in situ hybridization.
Mol Biol Rep. 2013; 40(7):4161-71 [PubMed
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We reinvestigated rearrangements occurring in region q13 of chromosome 11 aiming to: (i) describe heterogeneity of the observed structural alterations, (ii) estimate amplicon size and (iii) identify of oncogenes involved in laryngeal cancer progression as potential targets for therapy. The study included 17 cell lines derived from laryngeal cancers and 34 specimens from primary laryngeal tumors. The region 11q13 was analyzed by fluorescence in situ hybridization (FISH), array comparative genomic hybridization (aCGH) and gene expression microarray. Next, quantitative real time PCR was used for chosen genes to confirm results from aCGH and gene expression microarray. The observed pattern of aberrations allows to distinguish three ways, in which gain and amplification involving 11q13 region may occur: formation of a homogeneously staining region; breakpoints in/near 11q13, which lead to the three to sevenfold increase of the copy number of 11q13 region; the presence of additional copies of the whole chromosome 11. The minimal altered region of gain and/or amplification was limited to ~1.8 Mb (chr.11:69,395,184-71,209,568) and comprised mostly 11q13.3 band which contain 12 genes. Five, out of these genes (CCND1, ORAOV1, FADD, PPFIA1, CTTN) had higher expression levels in comparison to healthy controls. Apart from CCND1 gene, which has an established role in pathogenesis of head and neck cancers, CTTN, ORAOV1 and FADD genes appear to be oncogene-candidates in laryngeal cancers, while a function of PPFIA1 requires further studies.
G-rich T-oligos (GT-oligos; oligonucleotides with homology to telomeres) elicit a DNA damage response in cells and induce cytotoxic effects in certain tumor cell lines. We have previously shown that GT-oligo inhibits growth, arrests cell cycle, and induces apoptosis in ovarian, pancreatic, and prostate cancer cells. However, not all ovarian cancer cell lines are susceptible to GT-oligo exposure. GT-oligo was found to induce transcript expression of the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptors DR-4 and DR-5, which are generally silenced in ovarian cancer cells, rendering them insensitive to TRAIL. Exposure of TRAIL- and GT-oligo-resistant cell lines to GT-oligo rendered them sensitive to the cytotoxic effects of TRAIL, producing more than additive inhibition of growth. An intracellular inhibitor of the extrinsic apoptotic pathway, FLICE-like Inhibitory Protein-Short (FLIPs), was down-regulated and Jun kinase (JNK) was activated by exposure to GT-oligo. JNK inhibition partially reversed the growth inhibition caused by the combination of GT-oligo and TRAIL indicating partial involvement of the Jun kinase pathway in the resulting cytotoxic effect. Both capase-8 and caspases 3/7 were activated by exposure to GT-oligo plus TRAIL, consistent with activation of the extrinsic apoptotic pathway. These results demonstrate a novel way of sensitizing resistant ovarian cancer cells to TRAIL-mediated cytotoxicity.
Gong J, Kumar SA, Graham G, Kumar APFLIP: molecular switch between apoptosis and necroptosis.
Mol Carcinog. 2014; 53(9):675-85 [PubMed
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Cancerous growth is one of the most difficult diseases to target as there is no one clear cause, and targeting only one pathway does not generally produce quantifiable improvement. For a truly effective cancer therapy, multiple pathways must be targeted at the same time. One way to do this is to find a gene that is associated with several pathways; this approach expands the possibilities for disease targeting and enables multiple points of attack rather than one fixed point, which does not allow treatment to evolve over time as cancer does. Inducing programmed cell death (PCD) is a promising method to prevent or inhibit the progression of tumor cells. Intricate cross talk among various programmed cell death pathways including cell death by apoptosis, necroptosis or autophagy plays a critical role in the regulation of PCD. In addition, the complex and overlapping patterns of signaling and lack of understanding of such networks between these pathways generate hurdles for developing effective therapeutic approaches. This review article focuses on targeting FLIP (Fas-associated death domain-like interleukin-1-converting enzyme-like inhibitory protein) signaling as a bridge between various PCD processes as an effective approach for cancer management.
Markovic O, Marisavljevic D, Cemerikic-Martinovic V, et al.c-FLIP does not correlate with response to immunochemotherapy treatment and outcome of patients with nodal diffuse large B-cell lymphoma.
Biomed Pharmacother. 2013; 67(5):445-9 [PubMed
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UNLABELLED: Cellular FLICE-inhibitory protein (c-FLIP) is a critical anti-apoptotic regulator that inhibits apoptosis-inducing ligand, (TRAIL)-induced apoptosis as well as chemotherapy-triggered apoptosis in malignant cells. The present study was designed to investigate the clinical and prognostic significance of c-FLIP expression in patients with nodal diffuse large B-cell lymphoma (DLBCL) treated with immunochemotherapy.
METHODS: We have analyzed lymph node biopsy specimens, obtained from 60 patients with newly diagnosed nodal DLBCL treated with immunochemotherapy (R-CHOP or R-EPOCH). The expression of c-FLIP was analyzed using the standard imunohistochemical method on formalin-fixed and routinely processed paraffin-embedded lymph node specimens and evaluated semi quantitavely as a percentage of tumor cells.
RESULTS: c-FLIP immunoexpression (>50% positive tumor cells) has been found in 28 (46.7%) patients, and observed as cytoplasmic staining. There was not significant difference in c-FLIP immunoexpression between GCB and non-GCB subtype of DLBCL (P=0.639). Besides, c-FLIP immunoexpression had no significant association with IPI, "bulky" disease, extranodal localization, haemoglobin, Ki-67 immunoexpression or other clinico-pathological parameters. c-FLIP positivity has no significant influence on therapy response and survival in patients with DLBCL (P=0.562 and P=0.093, respectively). Patients with c-FLIP overexpression did not relapse more often that patients without expression of this apoptotic protein (P=0.365).
CONCLUSION: Our results suggest that c-FLIP immunoexpression can not be used as a prognostic factor in patients with nodal DLBCL treated with immunochemotherapy.