We found that the reduced AMPK B1 is consistent with the lower AMPK activity that is found in advanced stage, high grade and metastatic ovarian cancers. Crizotinib ALK Using gain and loss of function strategies, we demonstrated that AMPK B1 profoundly impairs cell growth, migration and invasion capacities via activating AMPK but attenuating AKT, ERK and JNK activ ities in advanced ovarian cancer cells. To our knowledge, this is the first comprehensive study of AMPK B1 ex pression, function and mechanism of action in human cancer cells. Recent studies have suggested that AMPK acts as a metabolic tumor suppressor due to its roles in governing the activities of mTOR, p53 and other regulatory mole cules as well as fatty acid synthesis. Hence, tumor cells must reduce the activity of AMPK to maintain their high proliferative capacity in oncogenesis.

Loss of LKB1 is a well known mechanism in suppressing AMPK activity and is commonly found in lung cancer, melanoma, gastro intestinal carcinoma and dysplastic hamartoma in Peutz Inhibitors,Modulators,Libraries Jeghers syndrome. However, most human cancers with an intact LKB1 function Inhibitors,Modulators,Libraries still maintain low AMPK ac tivity when exerting their tumorigenic properties, indicating that multiple mechanisms exist that depress AMPK activity in such cancer cells. AMPK is a heterotri meric complex consisting of a catalytic alpha subunit and regulatory beta and gamma subunits. We previously re ported that the AMPK subunits are differentially expressed and that different subunits have different clinical implica tions in the development of ovarian cancer.

Of these subunits, we found that the mRNA level of Inhibitors,Modulators,Libraries AMPK B1 was dominantly expressed and tightly correlated with AMPK activity when compared with AMPK B2 during the pro gression of ovarian cancer and other human cancers. Consistent with our previous findings, the IHC data in this study further Inhibitors,Modulators,Libraries demonstrates that AMPK B1 expres sion shows a stepwise reduction from early to late stage ovarian cancer. In addition, reduced AMPK B1 expression shows a significant association Inhibitors,Modulators,Libraries with late stage, high grade and metastatic ovarian cancers, suggesting that reduced AMPK B1 expression decreases AMPK activity and en hances the aggressiveness of advanced ovarian cancer.

Al though the underlying molecular mechanisms leading to the downregulation of AMPK selleck B1 during ovarian cancer progression remain unknown, the recent finding of the un derexpression of AMPK 2 in liver cancer cells indi cates that DNA methylation and histone deacetylation may be involved in silencing the expressions of AMPK subunits in ovarian cancer cells. Our results indicate that the inhibitory effect of AMPK B1 on cell growth is mediated through an increase in AMPK activation and a simultaneous decrease in AKT pathway activity. In the AMPK heterotrimeric complex, the AMPK B subunit acts as a scaffold to support the binding of the catalytic and regulatory subunits.

But, it was striking to note that the expres sion of HNF6, another important marker for late endo derm was still lower in the BMP4 dominant case. Hence, hierarchical clustering alone was not sufficient to answer if BMP4 addition could be useful for late endoderm differen tiation. Importantly, BMP4 dominant conditions gave low expression of markers www.selleckchem.com/products/Vandetanib.html from the robust biclusters. Thus the current analysis shows that BMP4 may not be a suitable choice for endoderm induction. WNT3AB catenin signaling has been shown to be im portant both for maintenance of pluripotency as well as induction of differentiation. The WNT pathway is also found to be important in the formation of primitive streak due to which it is often used in the very early stages of in vitro differentiation until the formation of mesendoderm.

Stabilization of B catenin by canonical WNT signaling is Inhibitors,Modulators,Libraries found to be responsible for differentiation by epithelial mesenchymal transition., Inhibitors,Modulators,Libraries however presence of Wnt after this stage supports mesoderm. Also, FGF2 is found to synergistically influence the WNT pathway. WNT alongwith PI3KI was commonly present in both the groups identified by our hierarchical clustering. WNT was consist ently found to be supportive to the activin FGF2 signal ing assessed by the up regulation of DE markers. Hence, Inhibitors,Modulators,Libraries WNT and PI3KI may be the essential pathway modulators necessary for endoderm differentiation. Robust biclusters identify the necessary pathways for efficient endoderm differentiation to the pancreatic lineage The robust biclusters identified by the biclustering bootstrap analysis show the most important trends pre served under experimental variations.

Supportively, CER, HNF6 and HNF4 belonged to the robust clusters. As mentioned earlier, CER is an important target Inhibitors,Modulators,Libraries of the acti vin and WNT signaling pathways and HNF6 is a very early pancreatic progenitor marker taking part in the transcriptional network activating pancreatic progenitors. As seen from the Group 1 bicluster, FGF2 WNT3A conditions favor CER and HNF6 while BMP4 limits their up regulation. Inhibitors,Modulators,Libraries It is also found that the stabil ity of B catenin is partly enhanced by PI3K signaling and hence this combination of high activin FGF2 WNT3A may work to control the expression of some endoderm markers like CER and HNF6.

At the same time, CER protein is a negative regu lator www.selleckchem.com/products/ganetespib-sta-9090.html of the Tgfb pathway and up regulation of CER is necessary to limit the activation of these pathways, since inhibition of the Tgfb pathway was found to be necessary for efficient differentiation to the pancreatic progenitors after PDX1 and HNF6 expression. However, external addition of WNT3A may still be necessary since CER negatively regulates the WNT path way. Alternatively, the markers HNF4 and HNF6 which occur in Group 2 are co regulated under.

The Enbrel and low dose TNF pretreat ment groups showed markedly decreased serum levels of ALT and AST at 180 min and 360 min together following liver IR. Several studies have demonstrated that IR related liver injury results from an severe inflammatory response involving the release of TNF by Kupffer cells, which alone can further intensify the inflammation Inhibitors,Modulators,Libraries reaction via the production of vascular adhesion molecules and neutrophil attracting chemokines. Our study in cluded a histopathological analysis to determine micro scopic changes in the liver following IR. The analysis revealed that compared to the CT26 group, the CT26 IR group showed markedly increased cytoplasmic vacuoliza tion, inflammatory cell infiltration, and hepatic cellular ne crosis, whereas the CT26 IR Enbrel and CT26 IR TNF groups showed significantly reduced cytoplasmic vacuolization, inflammatory cell infiltration, and hepatic cellular necrosis.

These results indicated that inhibition of TNF could protect against IR induced hepatic tissue damage through a decrease in TNF and the inflamma tory response. Indeed, inflammation plays Inhibitors,Modulators,Libraries a crucial role in promoting tumor development and Inhibitors,Modulators,Libraries metastasis, and there is much evidence to suggest that TNF is a key pro inflammatory cytokine Inhibitors,Modulators,Libraries involved in tumorigenesis. Previous studies reported that the upregulation of IL 6, MMP 9 and E selectin levels followed by IR were directly involved in hepatic damage. Meanwhile, IL 6 and MMP9 have been shown to promote the growth of colon cancer.

Our current study observed that both Enbrel and low dose TNF pretreat ments before IR markedly reduced the mRNA expressions of tumor promoting factors, IL 6 MMP 9 and E selectin in IR liver. Taken together, Inhibitors,Modulators,Libraries our results suggest inhibition of TNF in the tumor microenvironment through a reduction in inflammatory cell infiltration, following liver IR, and our findings are consistent with that of previous re search, for example, the inhibition or neutralization of TNF reduces the infiltration of inflammatory cells into hepatic tissue, and reduces liver IR injury. Studies have shown that inflammatory mediators can disrupt the extracellular matrix and cause tissue remodeling that allows tumor cell invasion, which could promote tumor cell proliferation, survival, invasion, chemoresis tance, and angiogenesis, and lead to the DNA histone methylation, eventually leading to lead to silen cing of tumor suppressor loci.

Achyut BR and his colleagues found that deletion of the TGF B recep tor2 gene in stromal fibroblasts induced inflammation and severely damaged DNA, and contributed to the de velopment of invasive squamous cell carcinoma. Taken together our findings suggest that TNF could up regulate the inflammatory selleck chem response following IR, and possibly produce a microenvironment that promotes tumor growth.

All together, these data demonstrate that OC ascites upregulate Mcl 1 expression in OC cells. Mcl 1 contributes to ascites induced attenuation of TRAIL mediated apoptosis Given its antiapoptotic activity, Mcl 1 could contribute to ascites induced attenuation thoroughly of TRAIL induced apop tosis. Thus, we investigated whether Mcl 1 inhibition can alter the prosurvival activity of OC ascites. First, CaOV3 cells were incubated with ascites in the presence or absence of TRAIL for 24 h. Long term cell survival was assessed by determining the fraction of sur viving colonies after two weeks. As shown in Figure 2A, the addition of OVC508 or OVC509 ascites to CaOV3 cells significantly enhanced the fraction of survival cells.

When apoptosis was determined by meas uring the sub G1 DNA content for CaOV3 and OVCAR3 cells incubated with ascites, we observed a 38% to 48% decreased of TRAIL induced apoptosis confirming that ascites attenuate TRAIL mediated cytotoxicity. These data confirmed that pretreatment with ascites attenuates TRAIL induced apoptosis Inhibitors,Modulators,Libraries in OC cells. When CaOV3 and OVCAR3 cells were compared dir ectly, the level of TRAIL induced apoptosis was higher in CaOV3 cells, consistent with the observation that CaOV3 cells expressed lower basal level of Mcl 1. To further assess the role of Mcl 1 in TRAIL resistance, CaOV3 cells were transfected with Mcl 1 or control siRNA and ex pression of Mcl 1 Inhibitors,Modulators,Libraries was assessed by immunoblot at 24 h Inhibitors,Modulators,Libraries and 48 h post transfection. Mcl 1 protein was effi ciently downregulated by Mcl 1 siRNA in CaOV3 cells.

Importantly, transfection of CaOV3 and OVCAR3 Inhibitors,Modulators,Libraries cells with Mcl 1 siRNA com pletely abrogated ascites induced Mcl Inhibitors,Modulators,Libraries 1 upregulation in both CaOV3 and OVCAR3 cells. Of note, the expression of antiapoptotic protein Bcl 2 and Bcl XL remained unaffected by Mcl 1 siRNA. Mcl 1 depletion significantly blocked the prosurvival activity of ascites in CaOV3 and OVCAR3 cells. As shown in Figure 2D, TRAIL induced apoptosis in CaOV3 cells whereas the presence of ascites, as expected, significantly inhibited TRAIL induced apop tosis. In CaOV3 cells transfected with Mcl 1 siRNA, the protective effect of ascites was almost com pletely abrogated. The transfection of Mcl 1 siRNA in OVCAR3 cells also significantly inhibited the protective effect of ascites albeit to a lesser extend. This could be related to the observation that the Mcl 1 siRNA did not completely block Mcl 1 expres sion in OVCAR3 cells.

OC ascites upregulate Mcl 1 through ERK1/2 signaling Activation of both ERK1/2 and Akt pathways has been linked to the transcriptional regulation of Mcl 1. Previous studies demonstrating Akt ac tivation by ascites prompted us to investigate whether Akt and ERK1/2 were involved in ascites mediated upregulation of Mcl 1 expression. First, we examined the phosphorylation of Akt and ERK1/2 selleck chemicals llc over time and found that both Akt and ERK1/2 were acti vated by ascites.

The beads were collected by centrifuga tion for 5 min at 15,000 g and 4 C, and washed 3 times with cold extraction buffer. The beads with immune complexes were boiled and electrophoresed on 8% SDS PAGE gels and analyzed by Western blotting using antibodies against c Myc, pMyc or DNA PKcs. Cells were transfected with 0. 1 uM siRNA Baricitinib for 48 h using oligofectamine according to the manufacturers instructions. In brief, the siRNA/oligofectamine complex was added to cells that were seeded in 6 well plate. The cells were incubated for 4 h at 37 C in serum free DMEM medium and then FBS was added. After 48 h, the cells were treated with TRAIL and collected for Western blot analysis to determine the levels of DNA PKcs, c Myc, and the indi cated proteins.

Apoptosis assay Untransfected control cells or transfected with the var ious siRNAs Inhibitors,Modulators,Libraries cells were treated with or without TRAIL and/or DMNB for Inhibitors,Modulators,Libraries the indicated times. The Inhibitors,Modulators,Libraries cells were centrifuged and resuspended in 500 ul of a staining solution containing Annexin V fluorescein and propidium iodide in PBS. After incubation at room temperature for 15 min, the cells were analyzed by flow cytometry. Annexin V binds to cells that express phosphatidyl serine on the outer layer of their cell membrane, and propidium iodide stains the cellular DNA of cells with a compro mised cell membrane. This allows for the discrimina tion of live cells from apoptotic cells and necrotic cells. Background Epithelial to mesenchymal transition is a biologi cal process in polarized epithelial cells, which occurs in various physiological and pathological conditions.

Complete EMT is characterized by spindle like cell morphology, loss of epithelial cellular markers such as E cadherin, and gain of mesenchymal phenotype by expressing filament Inhibitors,Modulators,Libraries proteins including vimentin and a smooth muscle actin. Cells undergoing EMT are highly mobile and invasive. During embryonic development, EMT enables cells to migrate or invade into neighboring tissues and maturate or differentiate into specialized cells. In epithelial malignant pro gression, EMT has emerged as a critical player in regu lating cancer cell invasive phenotype. Acquiring EMT is a critical step for cancer cells to dissociate from a primary tumor mass and subsequently migrate and invade adjacent tissues for remote metastasis. Recently, EMT has been linked with cancer stem like phenotype in certain epithelia tumors. Inhibitors,Modulators,Libraries As demon strated, breast cancer cells express several cellular mar cell assay kers that resemble the stem like phenotype during their progression towards EMT. These observations highlight the importance of cellular EMT program in tumorigenic progression of cancer cells. Development of EMT in cancer cells is regulated and precisely controlled at different cellular levels.

Comparison of the over lapping Ewings sarcoma hits with the normal fibroblast cell line showed that 17 siRNAs are specific for the Ewings sarcoma cells. Heat map of the Z scores shows specificity of these 16 siRNA for decreasing cell number in Ewings sarcoma cells only as opposed selleckbio to a global lethal siRNA targeting PLK1 that also reduces proliferation of normal fibroblast cells. Of the 16 significant gene hits that modulated the growth and proliferation of Ewings sarcoma cell lines, two genes STK10 and, TNK2 were prioritized for further confirmation since both siRNAs targeting these genes were hits across all four Ewings sarcoma cell lines. Confirma tion also included siRNA to PLK1 as a general lethal positive control gene for comparison.

Confirmation of Inhibitors,Modulators,Libraries the effects of STK10, TNK2 and PLK1 silencing on growth and survival of Ewings sarcoma cells We confirmed the effects of silencing of STK10, TNK2, and PLK1 on growth and survival of Ewings sarcoma cells by repeating the cell based assay in 384 well plates using a different lot of siRNA having the same sequences as the kinase library siRNA. Silencing of STK10, TNK2 and PLK1 by both siRNA sequences inhibited cell growth in the four Ewings sarcoma cell lines as measured by cell number. siRNA against STK10 and TNK2 showed significant reduction in cell growth in both TC 32 and TC 71 cells. The effect of STK10 and TNK2 knockdown on cell growth was very similar to the effect of PLK1 knockdown in these cells. We next conducted the real time kinetic analysis to determine the effect of STK10 and TNK2 siRNA treatment on Ewings cancer cells using label free impedance growth assays.

The impedance analysis showed that the treatment of TC 71 cells Inhibitors,Modulators,Libraries with STK10 and TNK2 siRNA resulted in a very potent and sustained decrease in cell number compared to non silencing siRNA treatment. To demonstrate the silencing efficiency of the siRNAs tar geting TNK2 and STK10, TC Inhibitors,Modulators,Libraries 71 cells were transfected with either the specific siRNAs or non silencing siRNA and incubated at 37 C for 48 hours. qRT PCR was per formed using Taqman probes for both genes and GAPDH was used as an internal control in both the experiments. Fold change was calculated using the Delta Delta Ct method and the results showed that at least 70% knockdown was observed using specific siRNAs against STK10 and TNK2.

Further more, treatment of TC 32 cells with siRNA targeting STK10 and TNK2 showed decrease in proteins levels compared to untreated cells or non silencing siRNA treated Inhibitors,Modulators,Libraries cells. These results confirm Inhibitors,Modulators,Libraries that the siRNAs targeting STK10 and TNK2 led to specific gene knockdown in our experiments. Gene Silencing of STK10 selleck catalog and TNK2 induces apoptosis We next examined the effect of STK10 and TNK2 siRNA treatment on the induction of apoptosis in TC 71 cells using a high content, image based analysis of annexin V staining.

Sustained post transcriptional p21WAF1 expression is dependent on ERK activation In order to establish whether sustained activation of the MEK/ERK pathway plays a role in post transcriptional mediated p21WAF1 accumulation, RD cells, pre treated with U0126, were Sorafenib VEGFR-2 treated with TPA for different time intervals. p21WAF1 protein accumulation was insensitive to MEK inhibitor treatment for Inhibitors,Modulators,Libraries up to 2 days, after which it dropped to the level of untreated control cells, paralleling U0126 treatment alone. These results suggest that the post transcriptional mechanism of p21WAF1 induction might be strictly dependent on activated MEK/ ERK pathway. Constitutively active MEK1 or MEK2 and ERK1 and ERK2 siRNA transient trans fection experiments demonstrated that activated MEKs/ ERKs are upstream pathways of p21WAF1 expression.

The forced expression of MEK1 or MEK2 induced both ERK phosphorylation and p21WAF1 increased expression. Inhibitors,Modulators,Libraries RNA interference experiments were performed with both ERK1 and ERK2 siRNA in order to prevent TPA Inhibitors,Modulators,Libraries induced ERK1/2 activation. After 4 days of TPA treatment, we observed a lack of p21WAF1 expression combined with the down regulation of total and phospho ERKs in ERK1 and ERK2 siRNA co transfected cells, while ERK activation and p21WAF1 expression were present in control trans fected cells. All these experiments demonstrate that the post transcriptional mechanism of p21WAF1 expression is dependent on the ERK pathway in RD cells.

Dependence of p21WAF1 transcriptional expression and myogenic differentiation on the p38 pathway We have previously shown that the p38 pathway is acti vated concomitantly in both the activation and down reg ulation of the Inhibitors,Modulators,Libraries ERK pathway, and that its inhibition prevents myogenic differentiation and reverts the growth arrest state after prolonged treatment. Therefore, we investigated whether ERKs and p38 cooperate, as has recently been demonstrated in CC139 and Rat 1 cells, or act separately to induce p21WAF1 and growth arrest. For this purpose, RD cells were treated with TPA and U0126 in the presence or absence of the p38 specific inhibitor SB203580. SB203580 treatment did not alter TPA induced p21WAF1 expression, but it did reduce U0126 induced p21WAF1 expression, particularly after pro longed treatments . alone it only slightly enhanced the p21WAF1 basal level.

Furthermore, p38 inhibition affected neither the TPA induced expression of cyclin D1 nor the decrease medi ated by MEK/ERK inhibition. The pRb Inhibitors,Modulators,Libraries phosphorylation www.selleckchem.com/products/chir-99021-ct99021-hcl.html status is, moreover, modulated by SB203580 after 2 days in U0126 treated cells. Conversely, pRb phosphorylation in TPA treated cells is insensitive to SB203580. SB203580 alone does not affect pRb phosphorylation and the slight increase in p21WAF1 expression at prolonged treatments is not suffi cient to induce hypo phosphorylation of pRb.

CPA, another alkylating agent like cisplatin, showed no effect on immune cell infiltrates, viral replication or viral transgene expression www.selleckchem.com/products/kpt-330.html in experiments selleck bio performed in non obese diabetes/severe combined immunodeficient mice. Rather combined immunosuppressive effects of CPA they correlated with increased viral transgene expres sion and replication in a variety of tumor models. Moreover, adenvoiruses combined Inhibitors,Modulators,Libraries with cisplatin presented in vitro a significant increase of apoptosis of tumor cells but not normal cells in different tumor models. We next showed that phagocytosis of H 1PV infected MZ7 Mel cells by DC was enhanced in concordance with our previous data from other virus infected cells.

Thirdly, we analyzed DC maturation following incubation with H 1PV induced TCL by measuring the expression of the maturation Inhibitors,Modulators,Libraries markers, CD80, CD83 and CD86.

DC incubated Inhibitors,Modulators,Libraries with H 1PV induced MZ7 Mel cell lysates resulted in a dramatic increase in the pro portion of DC expressing maturation markers, support ing Inhibitors,Modulators,Libraries similar data with other melanoma models, and infection Inhibitors,Modulators,Libraries with the oncolytic reovirus. However, other viruses have been reported to directly infect DC Inhibitors,Modulators,Libraries causing lysis and blocking important immune Inhibitors,Modulators,Libraries reactions. We observed CTL activation following co incubation with DC, which had phagocytosed Inhibitors,Modulators,Libraries H 1PV infected SK29 Inhibitors,Modulators,Libraries Mel cells, which could be due to cross presenta tion. Activation occurred even if H 1PV alone was unable to stimulate the DC and our data are supported by other studies.

The increased release of pro inflammatory cytokines by DC indicates augmented CD4 and CD8 T cell activation.

Inhibitors,Modulators,Libraries In vivo, this may lead to a response against TAAs. As H 1PV induced melanoma lysates induced a much higher Inhibitors,Modulators,Libraries level of phagocytosis by DC than either irradiated or untreated cells, Inhibitors,Modulators,Libraries H 1PV may directly enhance immune stimulation, which has also been shown Inhibitors,Modulators,Libraries with other viruses. Further, we observed enhanced release of IL 6. Finally, there was a dramatic increase Inhibitors,Modulators,Libraries of TNF a and IL 6 following co culture of CTL with DC and lysates from H 1PV infected mela noma cells. This is consistent with data from other groups, where chemotherapeutic drugs like vincristine, paclitaxel or methotrexate enhanced DC maturation.

Pandha et al showed that treatment with cisplatin increased the cytotoxicity of oncolytic reovirus but effects on the immune system were negative.

The cyto kine production induced by reovirus was suppressed selleck chemical Vorinostat by cisplatin. In our system, the comparable combi nation with H Inhibitors,Modulators,Libraries 1PV Cisplatin DNA Synthesis did excellent validation not hinder the immune stimu latory effects. We further investigated the use of sunitinib in combi nation with H 1PV in the melanoma cell line SK29 Mel. We demonstrated that sunitinib decreases SK29 Mel cell viability and that this is enhanced in combination with H 1PV.

Discussion and conclusion In this study, we have investigated whether induction of TRAIL/zVAD/CHX induced programmed necrosis rep resents a viable strategy for the elimination of tumor cells. Necrosis has long been regarded as an accidental, non physiologic form of cell death, whereas caspase dependent apoptosis EPZ-5676 price was considered to be the only form of programmed Inhibitors,Modulators,Libraries and thus physiologically occurring cell death. This view has however been challenged by nu merous studies which have provided Inhibitors,Modulators,Libraries evidence for the ex istence of programmed forms of necrosis that do not depend on caspases but nevertheless follow defined molecular steps. While caspase dependent apoptosis is the major pathway leading to PCD, programmed ne crosis can act as a backup system when the apoptotic machinery fails or is inactivated.

It has been shown that programmed necrosis exerts critical functions in mul tiple patho physiological Inhibitors,Modulators,Libraries settings, e. g. the regulation of bone growth, ovulation, negative selection of Inhibitors,Modulators,Libraries lymphocytes, pancreatitis, epilepsy, ischemia reperfusion injury, Parkinsons, Huntingtons and Alzheimers disease, and cell destruction by Salmonella, Shigella, HIV and vaccinia virus. In contrast to apoptosis, a comprehensive pic ture of the signaling pathways of programmed necrosis is not yet available. In the most extensively studied model, TNF R1 elicits programmed necrosis via activation of RIPK1 and RIPK3, a step which is stimulated by the deubiquitinase CYLD and the deacetylase SIRT2, but nega tively regulated by the proteins FADD, FLIP, caspase 8 and members of the cIAP family.

Downstream of RIPK3, the proteins MLKL and PGAM5 Inhibitors,Modulators,Libraries contribute to programmed necrosis by promoting mitochondrial fragmentation. We have previously demonstrated that ceramide acts as an additional key molecule in death receptor mediated pro grammed necrosis. Furthermore, enzymes of the en ergy metabolism, the Bcl 2 family member Bmf and production of reactive oxygen species have been implicated as additional factors in programmed necrosis. The capacity to elicit programmed necrosis appears to be an intrinsic feature of death receptors and has been reported not only for TNF R1, but also for Fas/ CD95 and ectodermal dysplasia receptor. Inde pendently, we and others have demonstrated the ability to trigger programmed necrosis for human and murine TRAIL receptors.

In contrast to programmed ne crosis, the efficacy of TRAIL in the apoptotic elimination of tumor cells has been extensively demonstrated in clin ical trials employing mono or combination therapies. Consistent with the finding that TRAIL elicits apop tosis selectively in tumor but not primary cells, TRAIL was well normally tolerated in preclinical models at serum con centrations that were shown to be effective against cancer cells, as were agonistic TRAIL receptor anti bodies applied to patients in clinical trials using mono or combination therapies.