The mechanism of radiosensitization by YM155, a novel small molecule inhibitor of survivin expression, is associated with DNA damage repair

BACKGROUND/AIMS

Survivin, a member of the inhibitor of apoptosis protein family, is an attractive target for cancer therapy. We investigated the effects of YM155, a small molecule inhibitor of survivin expression, on the radiosensitivity of human non-small cell lung cancer (NSCLC) cell lines and elucidated a relationship between the cellular localization of survivin and DNA double-strand break repair.

METHODS

The cellular distribution of survivin was determined by Western blotting of subcellular fractions and by immunofluorescent staining in A549 NSCLC cells. Radiation-induced DNA damage was evaluated based on histone H2AX phosphorylation and foci formation. The relationship between the cellular localization of survivin and DNA double-strand break repair was analyzed by Western blotting and co-immunoprecipitations.

RESULTS

YM155 down-regulated survivin expression in NSCLC cells in a concentration- and time-dependent manner. An in vitro clonogenic survival assay revealed that YM155 increased the sensitivity of NSCLC cells to radiation. After irradiation, we observed a rapid accumulation of survivin in the nucleus. An immunofluorescent analysis of histone x03B3;-H2AX demonstrated that the inhibition of survivin expression by YM155 resulted in impaired DNA double-strand break repair. Co-immunoprecipitation assays using nuclear extracts revealed an interaction between survivin, Ku70, x03B3;-H2AX, and DNA-PKcs. Furthermore, S2056 autophosphorylation of DNA-PKcs was reduced in survivin-depleted cells.

CONCLUSIONS

These results suggested that YM155 sensitized NSCLC cells to radiation, at least in part by inhibiting DNA repair and enhancing apoptosis via the down-regulation of survivin expression. YM155 pretreatment inhibited DNA-PKcs autophosphorylation at S2056. Nuclear survivin was involved in DNA double-strand break repair via interactions with members of the DNA double-strand break repair machinery.

FOXM1 targets XIAP and Survivin to modulate breast cancer survival and chemoresistance

Drug resistance is a major hurdle for successful treatment of breast cancer, the leading cause of deaths in women throughout the world. The FOXM1 transcription factor is a potent oncogene that transcriptionally regulates a wide range of target genes involved in DNA repair, metastasis, cell invasion, and migration. However, little is known about the role of FOXM1 in cell survival and the gene targets involved. Here, we show that FOXM1-overexpressing breast cancer cells display an apoptosis-resistant phenotype, which associates with the upregulation of expression of XIAP and Survivin antiapoptotic genes. Conversely, FOXM1 knockdown results in XIAP and Survivin downregulation as well as decreased binding of FOXM1 to the promoter regions of XIAP and Survivin. Consistently, FOXM1, XIAP, and Survivin expression levels were higher in taxane and anthracycline-resistant cell lines when compared to their sensitive counterparts and could not be downregulated in response to drug treatment. In agreement with our in vitro findings, we found that FOXM1 expression is significantly associated with Survivin and XIAP expression in samples from patients with IIIa stage breast invasive ductal carcinoma. Importantly, patients co-expressing FOXM1, Survivin, and nuclear XIAP had significantly worst overall survival, further confirming the physiological relevance of the regulation of Survivin and XIAP by FOXM1. Together, these findings suggest that the overexpression of FOXM1, XIAP, and Survivin contributes to the development of drug-resistance and is associated with poor clinical outcome in breast cancer patients.

Tanshinone IIA enhances the effects of TRAIL by downregulating survivin in human ovarian carcinoma cells

BACKGROUND

Tanshinone IIA (TIIA), a diterpene quinone from the medicinal plant Salvia miltiorrhiza Bunge (Lamiaceae) was shown to possess apoptotic and TRAIL-sensitizing effects. Still, the molecular mechanisms whereby TIIA induces apoptosis remain largely unknown.

PURPOSE

The role of survivin, an inhibitor of apoptosis protein, in TIIA-induced apoptosis has never been addressed before and hence was the primary goal of this study.

METHODS

In this study, we explored the anticancer effect of TIIA in TOV-21G, SKOV3, and OVCAR3 ovarian carcinoma cells. Cytotoxicity was determined by MTS assay. Real-time RT-PCR and Western blotting were used to assess the mRNA and protein expression of related signaling proteins.

RESULTS

Our results illustrated that TIIA's cytotoxic effect was caused by apoptosis with the involvement of caspases activity. Moreover, TIIA downregulated survivin in a concentration-dependent manner without affecting the expression of Bcl-2, Bcl-xL, and Bax. TIIA-induced survivin downregulation is regulated by both transcriptional processes and proteasomal degradation. Using TOV-21G cells as our cellular model, we demonstrated that TIIA-induced survivin downregulation requires p38 MAPK activation. Importantly, genetic overexpression of survivin rendered cells more resistant to TIIA, indicating an essential role of survivin downregulation in TIIA-induced apoptosis. This TRAIL sensitization effect of TIIA is ascribed to survivin downregulation because the effect was abrogated in cells that overexpressed survivin.

CONCLUSION

Our findings provide new insights into the action modes of TIIA-mediated anticancer effects and further implicate a rational design for cancer therapeutic regimens by combining TIIA-sensitized TRAIL via downregulating survivin to elicit ovarian cancer cell death.

Prognostic value of survivin and EGFR protein expression in triple-negative breast cancer (TNBC) patients

Triple-negative breast cancer (TNBC) is a particular type of breast cancer which is characterized by its biological aggressiveness, worse prognosis, and lack of prognostic markers or therapeutic targets in contrast with hormonal receptor-positive and human epidermal growth factor receptor 2-positive (HER2+) breast cancers. We aimed to evaluate survivin and epidermal growth factor receptor (EGFR) expression and their prognostic value and determine their relationships with the clinicopathological parameters of TNBC. A total of 136 patients who had undergone a resection of primary TNBC were enrolled at the Third Affiliated Hospital of Harbin Medical University from March 2003 to September 2005. Expression of ER, PR, HER2, EGFR, and survivin was assessed by immunohistochemistry. The association of TNBC and other clinicopathological variables and the prognostic value of survivin and EGFR expression were evaluated. Survivin was expressed in 62 (45.6 %) cases and EGFR was expressed in 82 (60.3 %) cases. Survivin expression was associated with menopausal status (P = 0.011), tumor size (P = 0.037), and lymph node status (P = 0.001). EGFR expression was associated with menopausal status (P = 0.029), lymph node status (P = 0.004), P53 expression (P = 0.001), Ki-67 expression (P = 0.028), and lymphatic vascular invasion (P = 0.037). A multivariate analysis demonstrated that tumor size (hazard ratio (HR) 1.587, 95 % confidence interval (CI) 1.081–2.330, P = 0.018 for disease-free survival (DFS); HR 1.606, 95%CI 1.096–2.354, P = 0.015 for overall survival (OS)), lymph node status (HR 2.873, 95%CI 1.544–5.344, P = 0.001 for DFS; HR 2.915, 95%CI 1.553–5.471, P = 0.001 for OS), tumor grade (HR 1.914, 95%CI 1.218–3.007, P = 0.005 for DFS; HR 1.983, 95%CI 1.228–3.203, P = 0.005 for OS), EGFR (HR 3.008, 95%CI 1.331–6.792, P = 0.008 for DFS; HR 3.151, 95%CI 1.374–7.226, P = 0.007 for OS), and survivin (HR 1.573, 95%CI 1.087–2.277, P = 0.016 for DFS; HR 1.607, 95%CI 1.088–2.374, P = 0.017 for OS) were of prognostic significance for disease-free and overall survival. We draw a conclusion from the present study that survivin and EGFR expression are useful prognostic markers of TNBC and might be useful for molecular targeting therapy of TNBC treatment.

Prognostic and Clinicopathological Value of Survivin in Diffuse Large B-cell Lymphoma: A Meta-Analysis

Up to date, survivin, a well-known inhibitor of apoptosis, has attracted considerable attention as a potential biomarker and therapeutic target in diffuse large B-cell lymphoma (DLBCL). Nevertheless, there still remains no consensus on heterogeneous results. Herein, a meta-analysis was performed to clarify a convincing significance of survivin status on prognosis and clinicopathology of DLBCL patients.Eligible studies were identified by searching Medline, Embase, Scopus, CNKI, and Wanfang databases (last updated on November 30, 2014). Pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Heterogeneity and sensitivity were also analyzed. Moreover, Begg, Egger test, and funnel plots were applied to evaluate the publication bias.We finally included 17 eligible studies with the total number of 1352 patients in the meta-analysis. The pooled results showed that positive survivin expression in DLBCL was associated with inferior overall survival (OS) (HR: 1.880, 95% CI: 1.550-2.270) in patients. Moreover, a significant association was revealed between survivin expression and advanced clinical stage (III + IV) (OR: 0.611, 95% CI: 0.452-0.827), higher International Prognosis Index (IPI) score (Score 3-5) (OR: 0.559; 95% CI: 0.410-0.761), elevated serum lactic dehydrogenase (LDH) (OR: 0.607, 95% CI: 0.444-0.831), presence of bone marrow involvement (OR: 2.127, 95% CI: 1.154-3.921) together with reduced complete remission (CR) rate (OR: 0.478, 95% CI: 0.345-0.662).The results suggest that survivin could be a useful prognostic biomarker, and a promising target for DLBCL therapeutic intervention. Considering limited HR data adjusted for standard prognostic variables could be retrieved, future high-quality studies will be needed in evaluating the independent prognostic value of survivin expression in DLBCL.

Altered expression profile of apoptosis-related molecules correlated with clinicopathological factors in non-small-cell lung cancer

Apoptosis-related molecules can be abnormally expressed in cancers and underscore the hallmark of resisting cell death in cancer cells. This study was aimed to observe the expression patterns of apoptosis-related molecules in lung cancer and paired non-cancerous tissues, and to observe if there is a correlation between the expression of these apoptotic molecules and clinicopathologic parameters. Immunohistochemistry (IHC) was performed to analyze the expression level of CASP3, CASP8, CASP9, PARP1, Cleaved CASP3 (C-CASP3), Cleaved PARP1 (C-PARP1), XIAP, BIRC5 (Survivin) and BCL2 in lung cancer and paired non-cancerous tissues. We found that apoptosis-related molecules CASP3, CASP9, BCL2, BIRC5 and PARP1 are abnormally expressed in lung cancer cells and their expression were correlated with histology. BCL2, BIRC5 and PARP1 are expressed at higher levels in SCC than in non-SCC. C-PARP1 expression might be an independent prognostic factor for NSCLC.

Antitumor activity of a novel survivin siRNA

Breast cancer resistance to therapy can result from expression of antiapoptotic genes. Survivin is an antiapoptotic gene that is over expressed in most human tumors. RNA interference using short interfering RNA (siRNA) can be used to specifically inhibit survivin expression. A novel siRNA targeting survivin was used to process MCF-7 cells. Cellular survivin mRNA and protein levels were determined by real-time qRT-PCR and Western blot, respectively. Cellular morphology and cell cycle were determined by fluorescence microscopy and flow cytometry. Cell proliferation was measured by MTT assay. Our data showed that the novel survivin-targeted siRNA could efficiently knockdown the expression of survivin, inhibit cell proliferation and cell cycle, especially at the G2/M checkpoint. These data suggest that the siRNA has potential for therapeutic applications.

Elevated survivin mediated multidrug resistance and reduced apoptosis in breast cancer stem cells

PURPOSE

Overexpression of survivin in breast cancer cells is associated with aberrant inhibition of apoptosis which leads to massive proliferation of cancer cells. Downregulation of survivin by the anticancer agent prodigiosin can efficiently induce apoptosis in cancer cells.

METHODS

The levels of survivin expression in breast cancer stem like side population (SP) cells were assessed. Analyzed were also the rate of apoptosis, drug resistance and the efficiency of clone formation of breast cancer SP cells after treatment with progiosin.

RESULTS

Breast cancer samples contained about 2.7% of cancer stem like SP cells which possessed elevated mRNA expression of stem cell proteins Oct-4, EpCAM and ABC transporter ABCG2, essential for the maintenance of SP cells. Furthermore, the SP cells displayed overexpression of survivin in conjunction with reduced apoptosis and increased multidrug resistance. After treatment with prodigiosin, the SP cells became more sensitive to apoptosis and to several chemotherapeutic agents.

CONCLUSION

These data suggest that increased expression of survivin in SP cells is one of the major factors involved in apoptosis and resistance to chemotherapy.

Prolactin-stimulated survivin induction is required for beta cell mass expansion during pregnancy in mice

AIMS/HYPOTHESIS

Prolactin (PRL)-stimulated beta cell proliferation is critical for maternal pancreatic beta cell mass expansion during pregnancy. However, the molecular effectors of the multiple putative signalling pathways downstream of the PRL receptor (PRL-R) are still elusive. Survivin has been shown to be induced during pregnancy. The aim of the present study was to define the essential role of survivin in gestational beta cell mass expansion.

METHODS

Expression of survivin was assessed in mouse islets during pregnancy and in insulinoma cells (INS-1) stimulated with PRL. Pregnant mice with targeted deletion of the survivin gene (also known as Birc5) in beta cells were assessed to determine the essential function of survivin in maternal beta cell mass expansion. INS-1 cells stimulated with PRL were used to explore the role of survivin in signalling pathways downstream of the PRL-R.

RESULTS

Survivin was significantly upregulated in maternal islets during pregnancy. With PRL stimulation, induction of survivin expression occurred predominantly in the nucleus and was associated with cell cycle progression to S and G2/M phase. Beta cell-specific survivin-knockout pregnant mice displayed glucose intolerance, attenuated beta cell mass expansion and impaired beta cell proliferation, with significant attenuation in the increased expression of Cdk4/Ccnd1, E2f1, p53 (also known as Trp53) and p21 (also known as Cdkn1a) compared with wild-type controls during pregnancy. Targeted deletion of survivin in INS-1 cells resulted in cell cycle disturbance with an arrest in G1/S phase after PRL stimulation. Inhibitors of Akt, signal transducer and activator of transcription 5 (STAT5), PIM or extracellular signal-regulated kinase (ERK), significantly decreased the expression of survivin in PRL-stimulated INS-1 cells.

CONCLUSIONS/INTERPRETATION

Survivin directly participates in PRL-mediated beta cell proliferation via Akt, STAT5-PIM and ERK signalling pathways during pregnancy.

Establishment of stable multiple myeloma cell line with overexpressed PDCD5 and its proapoptosis mechanism

OBJECTIVE

The transfected multiple myeloma cell line showing a stable doxycycline (DOX)-induced expression of PDCD5 was established. PDCD5 overexpression in the transfected cell line was analyzed for its effect on the dexamethasone (DXM)-induced apoptosis along with a discussion on the mechanism.

METHODS

(1) Lentiviral plasmid was used for the transfection of PDCD5 gene into the multiple myeloma cells. The screening was done by applying puromycin, and PDCD5 expression was induced by DOX. Real-time fluorescence quantitative PCR and Western Blot were performed to detect the expression levels of the target gene in the stable transfection group and the empty vector group; (2) The cell apoptosis rates of stable transfection group, blank group and empty vector group were measured by Annexin-APC/PI double staining flow cytometry; (3) Real-time fluorescence quantitative PCR and Western Blot were carried out to detect the expression levels of survivin, casepase-3 and Bcl-2 genes and proteins.

RESULTS

PDCD5 expression was significantly increased in the stably tranfected multiple myeloma cells compared with blank group and empty vector group. The cells in the transfection group were more sensitive to DXM, and the proportion of apoptotic cells was obviously higher than that of the blank group and the empty vector group (P<0.05). Survivin and Bcl-2 were considerably downregulated in U266/PDCD5 cells and combined DXM group than in the single agent group. However, caspase-3 was significantly upregulated.

CONCLUSION

Multiple myeloma cell line transfected with endogenous PDCD5 gene was established. The endogenous PDCD5 overexpression accelerated the cell apoptosis under DXM induction. The proapoptotic action of PDCD5 gene had the effect of activating casepase-3 and downregulating survivin and Bcl-2, which further promoted the apoptosis of multiple myeloma cells.

[Expressions and correlations of Survivin, Ki67 and p53 in laryngeal squmous cell carcinoma]

OBJECTIVE

To investigate the expression of Survivin, p53 and Ki67 in laryngeal carcinoma and the relation with clinical data.

METHOD

Immunohistochemical staining (SP) was used to detect expression of Survivin, p53 and Ki67 of 64 cases with laryngeal carcinoma, 26 cases with precancerosis, 34 cases with vocal polyps.

RESULT

The positive expression rates of Survivin, p53 and Ki67 were 59.4%, 68.8%, 65.6% respectively in laryngeal carcinoma, which were significantly higher than those in precancerosis and vocal polyps (P < 0.01). The expression of Survivin, p53 and Ki67 in laryngeal carcinoma were significantly statistical different in TNM stage and lymph node metastasis (P < 0.05), but were not correlated with patients' ages, the pathological grades, 3 years and 5 years surviving rates (P > 0.05). The expression of Survivin, Ki-67 and p53 was positively correlated (r = 0.607, 0.541, 0.648, P < 0.01) in laryngeal carcinoma.

CONCLUSION

Survivin, p53 and Ki-67 may play an important role in the carcinogenesis and progress of laryngeal carcinoma. They may play synergetic roles in the process of carcinogenesis of laryngeal carcinoma.

Nicotinamide phosphorybosiltransferase overexpression in thyroid malignancies and its correlation with tumor stage and with survivin/survivin DEx3 expression

Nicotinamide phosphorybosiltransferase (NAMPT) plays an important role in the regulation of cellular growth, angiogenesis, and apoptosis in mammalian cells. NAMPT overexpression has been recently found in colorectal, breast, prostatic, gastric, esophageal, pancreatic cancers, and specific NAMPT inhibitors might be adjuvant therapeutic modalities. In this study, we analyzed NAMPT expression in 40 malignant and in 67 benign thyroid tissue samples using qPCR. We also investigated relationships between NAMPT expression and survivin/survivin splicing variants DEx3 and 2B expressions. NAMPT expression was significantly higher in thyroid cancers (P < 0.0001), and it was positively correlated with tumor stage (P = 0.0012; r = 0.493). NAMPT expression was significantly higher in tumors staged pT3 or pT4 (16 cases) than in tumors staged pT1 or pT2 (24 cases) (P = 0.0106). Metastases to the lymph nodes were found in 12 out of 40 cases, and NAMPT expression was higher in the metastatic group (P = 0.0258). Multifocality was not associated with higher NAMPT expression (P = 0.3451). NAMPT expression in thyroid cancers significantly correlated with survivin and with survivin splice variant DEx3 expressions (P < 0.0001; r = 0.624 and P = 0.0239; r = 0.357, respectively). There was no correlation between NAMPT and survivin 2B expressions (P = 0.3508). This is the first study demonstrating NAMPT overexpression in thyroid malignancies using quantitative RT-PCR. Moreover, it shows that NAMPT is upregulated in patients with more advanced tumor stage and metastatic disease which may prove to be clinically relevant. Further studies are needed to explain the role of NAMPT in thyroid cancer biology and the possible use of NAMPT inhibitors in thyroid cancer.

Early tumor-cell gene expression changes may predict the response to first-line bortezomib-based therapy in patients with newly diagnosed multiple myeloma

PURPOSE

Maximizing the response rate to first-line therapy in patients with multiple myeloma (MM) is important because it leads to improved outcome. Gene-expression studies have identified prognostic gene sets in patients receiving bortezomib-based therapy. Comparison of the lists of genes derived from two gene-expression-based models (GEP70, GEP80) showed that they overlap in three genes, namely PSMD4, BIRC5, and KIAA1754. An unanswered question is whether early gene-expression changes can be used as predictors of the response to first-line bortezomib. In this study we aimed to examine the predictive value of gene expression changes for the depth of response after bortezomib-based therapy in newly diagnosed MM.

METHODS

We prospectively assessed the relation between early PSMD4, BIRC5, and KIAA1754 gene expression changes (before therapy and one week later) and the response rate after bortezomib-based therapy in 25 patients with newly diagnosed MM. Gene expression was studied by RT-PCR on CD138-selected plasma cells, and changes were recorded as upregulation, downregulation, or unchanged.

RESULTS

Whereas baseline prognostic factors including genetic lesions and stage were not predictive of the response rate, we found that early BIRC5 and KIAA1754 gene-expression changes were significantly associated with the depth of response to bortezomib (p=0.001 and p<0.001, respectively). PSMD4 was not predictive of the depth of response. KIAA1754 upregulation was linked to complete remission (CR) or very good partial remission (VGPR). BIRC5 upregulation was linked to stable disease (SD) or progressive disease (PD). We also observed that BIRC5 upregulation was associated with worse progression-free survival (PFS).

CONCLUSIONS

Our results suggest that BIRC5 and KIAA1754 gene-expression changes may predict the response to bortezomib-based therapy. These data may have relevance for the stratification and early adaptation of first-line treatment in patients with newly diagnosed MM.

Ex vivo generation of dendritic cells from cryopreserved, post-induction chemotherapy, mobilized leukapheresis from pediatric patients with medulloblastoma

Generation of patient-derived, autologous dendritic cells (DCs) is a critical component of cancer immunotherapy with ex vivo-generated, tumor antigen-loaded DCs. An important factor in the ability to generate DCs is the potential impact of prior therapies on DC phenotype and function. We investigated the ability to generate DCs using cells harvested from pediatric patients with medulloblastoma for potential evaluation of DC-RNA based vaccination approach in this patient population. Cells harvested from medulloblastoma patient leukapheresis following induction chemotherapy and granulocyte colony stimulating factor mobilization were cryopreserved prior to use in DC generation. DCs were generated from the adherent CD14+ monocytes using standard procedures and analyzed for cell recovery, phenotype and function. To summarize, 4 out of 5 patients (80%) had sufficient monocyte recovery to permit DC generation, and we were able to generate DCs from 3 out of these 4 patient samples (75%). Overall, we successfully generated DCs that met phenotypic requisites for DC-based cancer therapy from 3 out of 5 (60%) patient samples and met both phenotypic and functional requisites from 2 out of 5 (40%) patient samples. This study highlights the potential to generate functional DCs for further clinical treatments from refractory patients that have been heavily pretreated with myelosuppressive chemotherapy. Here we demonstrate the utility of evaluating the effect of the currently employed standard-of-care therapies on the ex vivo generation of DCs for DC-based clinical studies in cancer patients.

Research of inhibition of survivin in rat HSC-T6 cell by siRNA interference

OBJECTIVE

To explore the effects and mechanisms of siRNA targeting survivin of inducing apoptosis in rat HSC-T6 cells.

METHODS

The experiment was divided into blank group, pGPU6/GFP/Neo-shNC group and pGPU6/GFP/Neo-siRNA group. The siRNA was transfected into HSC-T6 cells mediated by LipofectamineTM2000 for 24 h, and then the efficiency of transfection was observed by fluorescence microscopy. After transfection for 48h, the expression of survivin mRNA and protein was assessed by reverse transcription-polymerase chain reaction (RT-PCR) method and Western-blot, and the form of cells was observed by microscopy. The apoptosis rate of HSC-T6 cells was measured by the flow cytometry with PI staining. The expression of caspase-3 protein was assessed by western-blot.

RESULTS

The prominent apoptosis of the pGPU6/GFP/Neo-siRNA group by PI staining was high, there was significant difference comparing with blank group and pGPU6/GFP/Neo- shNC group (p<0.05). The expression of caspase-3 by Western-blot in pGPU6/GFP/Neo-siRNA group was high, there was significant difference comparing with blank group and pGPU6/GFP/Neo-shNC group (p>0.05).

CONCLUSION

siRNA targeting survivin can inhibit the expression of survivin mRNA and protein in rat HSC-T6 cells. Expression of survivin is negative correlation with expression of caspase-3. siRNA targeting survivin may up-regulate expression of caspase-3 and increase apoptosis of rat HST-T6 (Fig. 6, Ref. 24).

The involvement of survivin in insulin-like growth factor 1-induced epithelial-mesenchymal transition in gastric cancer

It has been identified that insulin-like growth factor 1 (IGF-1) activated various pathways of the epithelial-mesenchymal transition (EMT) in a couple of tumors. At the same time, survivin is implicated in EMT of gastric cancer (GC). To date, the impact of survivin on IGF-1-mediated EMT of GC has not been featured. In this work, we used the immunohistochemistry and molecular and cellular experiments to investigate the existence and significance of IGF-1 and survivin. Our findings revealed that survivin protein can be observed in majority of samples in all GC samples. Importantly, survivin expression has an obvious association with GC stage, and metastasis. In vitro, GC cell line BGC823 was treated with different concentrations of IGF-1, resulting in the activation of p-ERK, p-AKT, survivin, and the expression of EMT biomarkers, including N-cadherin, MMP2, and Snail. However, the silencing of survivin eradicated the expression IGF-1-induced EMT biomarkers and affected the migration and invasion of BGC823 cells. In conclusion, IGF-1 signaling activated survivin expression and controlled the expression of EMT biomarkers in the development of GC. This study lays a new stage for the molecular therapy of GC patients in the clinical treatment.

Insulin Protects Cardiac Myocytes from Doxorubicin Toxicity by Sp1-Mediated Transactivation of Survivin

Insulin inhibits ischemia/reperfusion-induced myocardial apoptosis through the PI3K/Akt/mTOR pathway. Survivin is a key regulator of anti-apoptosis against doxorubicin-induced cardiotoxicity. Insulin increases survivin expression in cardiac myocytes to mediate cytoprotection. However, the mechanism by which survivin mediates the protective effect of insulin against doxorubicin-associated injury remains to be determined. In this study, we demonstrated that pretreatment of H9c2 cardiac myocytes with insulin resulted in a significant decrease in doxorubicin-induced apoptotic cell death by reducing cytochrome c release and caspase-3 activation. Doxorubicin-induced reduction of survivin mRNA and protein levels was also significantly perturbed by insulin pretreatment. Reducing survivin expression with survivin siRNA abrogated insulin-mediated inhibition of caspase-3 activation, suggesting that insulin signals to survivin inhibited caspase-3 activation. Interestingly, pretreatment of H9c2 cells with insulin or MG132, a proteasome inhibitor, inhibited doxorubicin-induced degradation of the transcription factor Sp1. ChIP assay showed that pretreatment with insulin inhibited doxorubicin-stimulated Sp1 dissociation from the survivin promoter. Finally using pharmacological inhibitors of the PI3K pathway, we showed that insulin-mediated activation of the PI3K/Akt/mTORC1 pathway prevented doxorubicin-induced proteasome-mediated degradation of Sp1. Taken together, insulin pretreatment confers a protective effect against doxorubicin-induced cardiotoxicity by promoting Sp1-mediated transactivation of survivin to inhibit apoptosis. Our study is the first to define a role for survivin in cellular protection by insulin against doxorubicin-associated injury and show that Sp1 is a critical factor in the transcriptional regulation of survivin.

[Effects of anti-survivin oligonucleotides on growth of peritoneally implanted ovarian cancer xenografts in nude mice]

OBJECTIVE

To observe the effect of anti-survivin oligonucleotides (ASODN) on the invasion and growth of peritoneally implanted ovarian cancer cell xenografts in nude mice.

METHODS

Nude mouse models bearing peritoneally implanted ovarian cancer cell (SKOV3) xenografts were established and subjected to intraperitoneal injection of survivin ASODN or saline (control). The number and weight of the intraperitoneal xenografts were compared between the two groups.The expressions of interleukin (IL-6), signal transducer and activator of transcription3 (STAT3), phosphorylated STAT3 (p-STAT3), and survivin protein in the tumor tissues were detected with Western blotting in both groups.

RESULTS

Compared with those in the control group, the number and weight of the intraperitoneal xenografts were significantly reduced in ASODN group (P<0.05). ASODN treatment also resulted in significantly lowered protein levels of IL-6, STAT3, p-STAT3, and survivin in the tumor tissues (P<0.05).

CONCLUSION

Survivin ASODN can suppress the invasion and migration capacity of ovarian cancer cells and inhibit peritoneal metastasis of the tumor in nude mice possibly though down-regulation of IL-6/STAT3 signaling pathway.

Survivin contributes to the progression of diabetic retinopathy through HIF-1α pathway

Hypoxia plays a critical role in the formation of diabetic retinopathy (DR). Hypoxia inducible factor-1α (HIF-1α) and survivin are upregulated following hypoxia, and contribute to the angiogenesis in cancer. The goal of our study was to investigate if the expression of HIF-1α and survivin is related to the retinal vascular change of rats with different stages of diabetes mellitus (DM). Wistar rats were randomly divided into DM for 1 month (DM1) group, DM3, DM6 group and normal control group. Streptozotocin (STZ) was used to induce diabetic rat models. Retinal vascular digest preparation was taken to observe the change of retinal microvessels. The expression of HIF-1α and survivin was determined by real-time PCR and Western blot. In DM3 group, capillaries became circuitous and irregular. Acellular capillary were detected in DM6 group. In the same time, the number of pericytes significantly decreased in DM3 and DM6 groups. The expressions of HIF-1α were more increased in the DM3 and DM6 groups. However, the expressions of survivin only were upregulated in DM6 group .These data suggest that HIF-1α induced the upregulation of survivin in the early stage of DR. Survivin contributed to the development and progression of DR through the HIF-1α pathway and become an important progression marker of DR.

Use of a Novel Integrase-Deficient Lentivirus for Targeted Anti-Cancer Therapy With Survivin Promoter-Driven Diphtheria Toxin A

As an immunotoxin, diphtheria toxin has been widely used in gene therapy and gene function assays for its roles in protein synthesis inhibition, and the aim of our study is to set up a nonintegrating lentiviral system for specific expression of diphtheria toxin A (DTA) used in cancer gene therapy.Here, we established a lentiviral system that could coordinately express fluorescent protein and DTA driven by the cytomegalovirus (CMV) promoter, which is convenient for us to precisely trace the expression of DTA and monitor the process of lentivirus packaging. To achieve safer cancer therapy, we replaced the CMV promoter with the Survivin promoter, a specific promoter that is dramatically activated in cancer tissues and cells, but not in normal tissues and cells, and that will impose greater therapeutic potential because a significant expression difference occurred between these 2 groups. Meanwhile, we obtained integrase-deficient lentivirus (IDLV) after packaging with the integrase mutant, which expresses defective integrase RRK262263264AAH, to minimize the side effects that derived from the insertional mutagenesis of the host genome.Our results suggest that the IDLV system that we generated possesses therapeutic potential in cancers in vitro and in vivo.

Survivin is not an independent prognostic factor for patients with upper tract urothelial carcinoma: a multi-institutional study

OBJECTIVE

Several small single-center studies have reported conflicting results on the prognostic value of survivin expression in upper tract urothelial carcinoma (UTUC) following radical nephroureterectomy. We attempted to validate the prognostic utility of survivin using a large multi-institutional cohort.

MATERIAL AND METHODS

Survivin expression was evaluated by immunohistochemistry in tumor tissue from 732 patients with unilateral, sporadic UTUC treated with radical nephroureterectomy between 1990 and 2008 at 7 centers. Survivin expression was considered altered when at least 10% of the tumor cells stained positive. Associations of altered survivin expression with recurrence-free survival (RFS) and cancer-specific survival (CSS) were evaluated using Cox proportional hazards regression models.

RESULTS

Altered survivin expression was observed in 288 (39.3%) tumors and was associated with more advanced pathological tumor stages (P<0.001), lymph node metastases (P<0.001), lymphovascular invasion (P<0.001), tumor necrosis (P = 0.027), and tumor architecture (P<0.001). Median follow-up was 35 (16-64) months. There were 191 (25.4%) patients who experienced disease recurrence, and 165 patients (21.9%) died of the disease. In the univariable analysis, altered survivin expression was significantly associated with worse RFS and CSS (each P<0.001); however, altered survivin expression did not achieve independent predictive status on multivariable models (P = 0.24 and P = 0.53). Similarly, survivin was not independently associated with outcomes in subgroup analyses, including patients with high-grade tumors.

CONCLUSIONS

In UTUC, altered survivin expression is associated with worse clinicopathological features and worse RFS and CSS. However, it does not appear to be independently associated with cancer outcomes when considering standard prognostic factors.

Pre-Vaccination Frequencies of Th17 Cells Correlate with Vaccine-Induced T-Cell Responses to Survivin-Derived Peptide Epitopes

Various subsets of immune regulatory cells are suggested to influence the outcome of therapeutic antigen-specific anti-tumor vaccinations. We performed an exploratory analysis of a possible correlation of pre-vaccination Th17 cells, MDSCs, and Tregs with both vaccination-induced T-cell responses as well as clinical outcome in metastatic melanoma patients vaccinated with survivin-derived peptides. Notably, we observed dysfunctional Th1 and cytotoxic T cells, i.e. down-regulation of the CD3ζchain (p=0.001) and an impaired IFNγ-production (p=0.001) in patients compared to healthy donors, suggesting an altered activity of immune regulatory cells. Moreover, the frequencies of Th17 cells (p=0.03) and Tregs (p=0.02) were elevated as compared to healthy donors. IL-17-secreting CD4⁺ T cells displayed an impact on the immunological and clinical effects of vaccination: Patients characterized by high frequencies of Th17 cells at pre-vaccination were more likely to develop survivin-specific T-cell reactivity post-vaccination (p=0.03). Furthermore, the frequency of Th17 (p=0.09) and Th17/IFNγ⁺ (p=0.19) cells associated with patient survival after vaccination. In summary, our explorative, hypothesis-generating study demonstrated that immune regulatory cells, in particular Th17 cells, play a relevant role for generation of the vaccine-induced anti-tumor immunity in cancer patients, hence warranting further investigation to test for validity as predictive biomarkers.

TD-60 links RalA GTPase function to the CPC in mitosis

TD-60 (also known as RCC2) is a highly conserved protein that structurally resembles the Ran guanine exchange factor (GEF) RCC1, but has not previously been shown to have GEF activity. TD-60 has a typical chromosomal passenger complex (CPC) distribution in mitotic cells, but associates with integrin complexes and is involved in cell motility during interphase. Here we show that TD-60 exhibits GEF activity, in vitro and in cells, for the small GTPase RalA. TD-60 or RalA depletion causes spindle abnormalities in prometaphase associated with abnormal centromeric accumulation of CPC components. TD-60 and RalA apparently work together to contribute to the regulation of kinetochore-microtubule interactions in early mitosis. Importantly, several mitotic phenotypes caused by TD-60 depletion are reverted by the expression of a GTP-locked mutant, RalA (Q72L). The demonstration that a small GTPase participates in the regulation of the CPC reveals a level of mitotic regulation not suspected in previous studies.

[Expression of Tcf-4, MMP7 and Survivin in Colorectal Cancer and Its Clinical Significance]

OBJECTIVE

To explore the clinical and pathological significance and correlations among the xpressions of Tcf-4, MMP7 and survivin in colorectal cancer.

METHODS

The expressions of Tcf-4, MMP7 and survivin mRNA in tumor tissues and adjacent normal mucosa from 50 colorectal cancer patients were detected by reverse transcription PCR (RT-PCR). The expressed proteins of Tcf-4, MMP7 and survivin were measured using mmunohistochemistry staining technique (Elivision) in 100 colorectal cancer samples and 60 normal mucosa tissue samples. We analyzed the correlations between those measurements and their associations with clinical and pathological characteristics.

RESULTS

Positive expressions of Tcf-4, MMP7 and survivin mRNA were found in both cancer and adjacent mucosa tissues, despite a higher level of expression in the cancer tissues (P < 0.01). Expressed proteins were detected in cancer tissues of 69.00% (69/100) of those with a positive Tcf-4 expression, 77.00% (77/100) of those with a positive MMP7 expression, and 65.00% (65/100) of those with a positive survivin expression. Compared with cancer tissues, lower levels of protein expression were found in normal mucosa tissues [16.67% (10/60) for Tcf-4, 13.33% (8/60) for MMP7 and 15.00% (9/60) for survivin, P < 0.01]. The expressions of Tcf-4, MMP7 and survivin were all associated with lymphatic metastasis and Dukes staging (P < 0.05). MMP7 expression was associated with depth of tumor invasion (P < 0.05). Survivin expression was associated with tumor differentiation. The Spearman rank correlation analyses showed that protein expressions in colorectal cancer tissues in those with a positive Tcf-4 were correlated with those with a positive MMP7 (r = 0.302) and those with a positive survivin (r = 0.279) (P < 0.01), but not in those with a positive MMP7 and those with a positive survivin (r = 0.097, P > 0.05).

CONCLUSION

The expression levels of Tcf-4, MMP7 and survivin are high in colorectal cancer, all being linked to lymph node metastasis and Dukes stages of patients. This suggests that they may be involved in the occurrence, development, malignant growth and clinical progression of colorectal cancer.

[Relationship of local recurrence with the expression of Survivin and MMP-2 in laryngeal carcinoma and its surgical margins]

OBJECTIVE

To explore the relationship of the local recurrence with the expression of protein Survivin and MMP-2 in the primary lesions and the surgical margins of laryngeal carcinoma.

METHOD

The primary lesions and the surgical margins of laryngeal carcinoma of 48 patients were made into serial sections. Immunochemical methods was used to detect the expression of protein Survivin and MMP-2 in the primary lesion and the surgical margins of laryngeal carcinoma of 48 patients.

RESULT

The positive expression for Survivin and MMP-2 in the primary lesion was 70.83% (34/48) and 66.67% (32/48) respectively, and the positive expression of Survivin and MMP-2 in the surgical margins of laryngeal carcinoma was 47.92% (23/48) and 37.50% (18/48), which in the primary lesion was significantly higher than those of the surgical margins of laryngeal carcinoma (P < 0.05). The recurrence rates of primary lesion positive for Survivin (34 cases) and MMP-2 (32 cases) were 26.47% (9/34) and 25.00% (8/32), which were higher than negative for them 7.14%(1/14) and 12.50% (2/16) (P > 0.05). The recurrence rates of those with Survivin (23 cases) and MMP-2 (18 cases) positive surgical margins were 34.78% (8/23) and 38.89% (7/18) respectively, which were significantly higher than those with negative ones 8.00% (2/25) and 10.00% (3/30) (P < 0.05). Logistic analysis showed that the expression of Survivin and MMP-2 protein in the surgical margins of laryngeal carcinoma was positively associated with the recurrence rates.

CONCLUSION

Laryngeal carcinoma patients with Survivin-positive or MMP-2-positive margin would have a higher recurrence rate. Survivin and MMP-2 protein can be used as biomarkers for local recurrence of laryngeal carcinoma after operation.

Guadecitabine (SGI-110) priming sensitizes hepatocellular carcinoma cells to oxaliplatin

Promoter DNA hypermethylation is an important biomarker of hepatocellular carcinoma (HCC), supporting the potential utility of demethylating agents in this disease. Guadecitabine (SGI-110) is a second-generation hypomethylating agent formulated as a dinucleotide of decitabine and deoxyguanosine that yields longer half-life and more extended decitabine exposure than decitabine IV infusion. Here we performed preclinical evaluation of SGI-110 in HCC models to guide the design of a phase I/II clinical trial. HCC cell lines and xenograft models were used to determine the antitumor activity of SGI-110 as a single agent and in combination with oxaliplatin. Pretreatment with low doses of SGI-110 significantly synergized with oxaliplatin yielding enhanced cytotoxicity. The combination of SGI-110 and oxaliplatin was well tolerated and significantly delayed tumor growth in mice compared to oxaliplatin alone. Bromouridine-labeled RNA sequencing (Bru-seq) was employed to elucidate the effects of SGI-110 and/or oxaliplatin on genome-wide transcription. SGI-110 and the combination treatment inhibited the expression of genes involved in WNT/EGF/IGF signaling. DNMT1 and survivin were identified as novel PD markers to monitor the efficacy of the combination treatment. In conclusion, SGI-110 priming sensitizes HCC cells to oxaliplatin by inhibiting distinct signaling pathways. We expect that this combination treatment will show low toxicity and high efficacy in patients. Our study supports the use of the combination of low doses of SGI-110 and oxaliplatin in HCC patients.

Design, Synthesis and Structure-Activity Relationship Studies of Novel Survivin Inhibitors with Potent Anti-Proliferative Properties

The anti-apoptotic protein survivin is highly expressed in most human cancer cells, but has very low expression in normal differentiated cells. Thus survivin is considered as an attractive cancer drug target. Herein we report the design and synthesis of a series of novel survivin inhibitors based on the oxyquinoline scaffold from our recently identified hit compound UC-112. These new analogs were tested against a panel of cancer cell lines including one with multidrug-resistant phenotype. Eight of these new UC-112 analogs showed IC₅₀ values in the nanomole range in anti-proliferative assays. The best three compounds among them along with UC-112 were submitted for NCI-60 cancer cell line screening. The results indicated that structural modification from UC-112 to our best compound 4g has improved activity by four folds (2.2 μM for UC-112 vs. 0.5 μM for 4g, average GI₅₀ values over all cancer cell lines in the NCI-60 panel).Western blot analyses demonstrated the new compounds maintained high selectivity for survivin inhibition over other members in the inhibition of apoptosis protein family. When tested in an A375 human melanoma xenograft model, the most active compound 4g effectively suppressed tumor growth and strongly induced cancer cell apoptosis in tumor tissues. This novel scaffold is promising for the development of selective survivin inhibitors as potential anticancer agents.

Evaluation of survivin splice variants in pituitary tumors

PURPOSE

Survivin is an apoptosis inhibitor, expressed in almost all types of human malignancies, but rarely in differentiated normal tissues. Recently, survivin gene splice variants with different anti-apoptotic activities have been reported. The current study was undertaken to examine the expression of survivin and its splice variants ∆Ex3 and 2β in pituitary tumors, and to correlate the amount of particular transcripts with clinical staging in pituitary adenomas. Quantitative detection of survivin and its splice variants ∆Ex3 and 2β transcripts in non-cancerous pituitary tissues (n = 12) and different types of pituitary tumor (n = 50).

METHODS

Samples were collected from 50 pituitary tumors including 26 non-functional tumors, 21 GH-secreting tumors, 2 PRL-secreting tumors and 1 ACTH-secreting tumor. 12 normal pituitary glands received after autopsy served as a control of the study. 29 thyroid cancers tissues were used as a positive control. The RT-qPCR with TaqMan hydrolysis probes were used to determine the expression of analyzed splice variants of survivin.

RESULTS

The obtained data showed that both survivin and its splice variants were expressed in different types of pituitary adenoma as well as in normal pituitary tissue. However, the level of its expression was similar in all studied cases. Patient age negatively correlated with tumor invasiveness. Moreover, our study showed a tendency for negative correlation between patient age and tumor diameter.

CONCLUSIONS

No significant differences between survivin and its splice variants ∆Ex3 and 2β expression in pituitary tumors and in normal pituitary glands as well as in invasive and in non-invasive tumors were found, suggesting that survivin does not play a significant role in pituitary tumorigenesis.

Elevated survivin expression in peripheral blood mononuclear cells is central to collateral formation in coronary chronic total occlusion

Survivin is essential to angiogenesis and revascularization, but its role in coronary collateral formation remains unclear. The role of survivin in peripheral blood mononuclear cells (PBMCs) of coronary chronic total occlusion (CTO) patients was investigated. Coronary CTO patients (n=46; mean age 60.1±8.5, male 54.3%) (CTO group) and normal control patients (n=18; mean age 58.0±10.0, male 55.6%) underwent angiographic collateral vessel grading by Rentrop classification (C0 - C3) and provided peripheral blood between June 2006 and February 2007. Rat hind limb ischemia models were constructed using four equal groups of Sprague-Dawley rats (n=36): normal control, sham operation, operation and granulocyte macrophage colony-stimulating factor (GM-CSF). PBMC numbers and characteristics, collateral vessels, survivin, CD4, CD8, CD44, vascular endothelial growth factor (VEGF) and intercellular adhesion molecule-1 (ICAM-1) expression were determined using RT-PCR, flow cytometry, immunocytochemistry and western blot analysis. PBMC survivin mRNA and protein expression levels were higher in patients with good collateral circulation (C2 + C3) than in patients with no collateral flow (C0) (all P<0.05). Survivin single-positive and survivin and CD8, VEGF and ICAM-1 double-positive percentages were elevated in patients with good collateral circulation compared to those with normal and no collateral flow (all P<0.05), consistent with the rat model results, wherein higher survivin levels produced significantly larger and more visible collateral vessels. In conclusion, elevated survivin expression in PBMCs, particularly survivin and CD8, VEGF, and ICAM-1 double-positive PBMCs, may be crucial for good collateral formation in patients with coronary CTO, as confirmed by assessment of a rat model.

[Inhibition Function of Dominant-negative Mutant Gene Survivin-D53A to SPC-A1 Lung Adenocarcinoma Xenograft in Nude Mice Models]

Survivin-D53A (SVV-D53A) is a dominant-negative mutant survivin, which represents a potential promising target for cancer gene therapy. The present study was designed to determine whether SVV-D53A plasmid encapsuled by DOTAP: Chol liposome would have the anti-tumor activity against SPC-A1 lung adenocarcinoma, and to detect the possible mechanisms. In our experiment, SPC-A1 cells were transfected in vitro with SVV-D53A plasmid and examined for protein expression by Western blot, then flow cytometric analysis was used to detect apoptosis. SPC-A1 lung adenocarcinoma xenografts were established in vivo in the nude mice, which received the i. v. administrations of SVV-D53A plasmid/liposome complexes. After mice were sacrificed, the paraffin-embedded tumor tissue sections were used for proliferating cell nuclear antigen (PCNA) expression and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Compared with the control group, the mice treated with SVV-D53A plasmid had an obviously reduced tumor volume, with high level of apoptosis and decreased cell proliferation in tumor tissue. The research results proved that the administration of SVV-D53A plasmid resulted in significant inhibition of SPC-A1 cells both in vitro and in vivo. The functional mechanism is that the anti-tumor response causes and induces tumor cell apoptosis.

Effect of antisense microRNA targeting survivin on rectal cancer HRC-9698 cells and its mechanism

BACKGROUND

Rectal cancer seriously threats to human health. Traditional chemotherapy drugs might kill rectal cancer cells while easy cause side effects and clinical complications. Therefore, it is necessary to explore possible new methods for rectal cancer treatment. Survivin is an important tumor-specific protein. Previous researches showed it may be closely related to nasopharyngeal carcinoma. Its role in rectal cancer remains unclear.

METHODS

Cultivate human rectal cancer HRC-9698 cells. Antisense microRNA targeting survivin and control miRNA were constructed and transfected to HRC-9698 cells. MTT assay was applied to detect cell growth. Flow cytometry was used to test cell apoptosis. Western blot was performed to detect Osteopontin expression level. Colony formation and transwell assay were used to test cell clone formation and invasion abilities.

RESULTS

Antisense microRNA targeting survivin can inhibit HRC-9698 cell proliferation and induce its apoptosis. Antisense microRNA targeting survivin decreased osteopontin expression level. Overexpressed osteopontin inhibited antisense microRNA targeting survivin induced cell apoptosis. Antisense microRNA targeting survivin suppressed HRC-9698 cells' colony formation and invasion abilities.

CONCLUSION

Antisense microRNA targeting survivin induced osteopontin participated HRC-9698 cell apoptosis. Antisense microRNA targeting survivin inhibited HRC-9698 cell colony formation and invasive abilities, indicating that survivin may play its anti-tumor effect through inducing cell apoptosis and inhibiting cell metastasis and invasion.

Knockdown of microRNA-127 reverses adriamycin resistance via cell cycle arrest and apoptosis sensitization in adriamycin-resistant human glioma cells

The aim of this study was to investigate signaling pathways for reversal of microRNA-127-mediated multi-drug resistance (MDR) in gliomas cells. Adriamycin-resistant glioma cell lines U251/adr and U87-MG/adr were established and we found that anti-microRNA-127 markedly reduced microRNA-127 expression levels in a time-dependent manner, leading to distinct inhibition of cell proliferation and increased apoptosis and the content of intracellular Rh123. Silencing of microRNA-127 significantly increased the sensitivity of U251/ADR and U87-MG/adr cells to adriamycin, compared to cells transfected with negative control siRNA. Silencing of microRNA-127 also significantly reduced the mRNA and protein expression levels of MDR1 and MRP1, which are major ATP-binding cassette (ABC) transporter linked to multi-drug resistance in cancer cells. And Runx2, p53, bcl-2 and survivin, which are important role in cell apoptosis, also markedly changed after microRNA-127 silencing. In addition, down-regulating microRNA-127 decreased the level of phosphorylated-Akt. Our data indicate that down-regulation of micorRNA-127 can trigger apoptosis and overcome drug resistance of gliomas cells. Therefore, this resistance of adriamycin in gliomas can be cancelled by silencing expression of microRNA-127.

Correlation between survivin genetic polymorphisms and lung cancer susceptibility

AIMS

The purpose of the study was to analyze the relationship of survivin polymorphisms including -31G/C, -625G/C, 9194A/G and 9809T/C with the susceptibility to lung cancer.

METHODS

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to test the polymorphisms of -31G/C, -625G/C, 9194A/G and 9809T/C in 104 patients with lung cancer and 104 healthy controls. Then, linkage disequilibrium and haplotypes were analyzed by HaploView software. The differences of genotype, allele and haplotype frequencies in case and control group were assessed via chi-square test. Odds ratio (OR) with 95% CI were used to evaluate the correlation of survivin polymorphisms with lung cancer.

RESULTS

Genotype distribution of each polymorphism site in control group was in agreement with Hardy-Weinberg equilibrium (HWE) (P>0.05). The frequency of -31G/C CC genotype and C allele in case group were much higher than that of controls, respectively (CC: 33.6% vs. 22.1%; C: 57.2% vs. 46.6%) and CC genotype as well as C allele were appeared to be risk factors for lung cancer. Meanwhile, 9194A/G GG genotype could increase the risk for lung cancer (OR=2.86, 95% CI=1.14-7.20). The risk of G allele carriers for lung caner was higher than that of A allele (OR=1.63, 95% CI=1.08-2.47). The haplotypes analysis indicated that CGGC and GCAT were associated with the susceptibility to lung cancer (OR=2.79, 95% CI=1.58-4.92; OR=2.36, 95% CI=1.29-4.30).

CONCLUSIONS

Survivin -31G/C and 9194A/G polymorphisms were associated with the risk of lung cancer. The CGGC and GCAT haplotypes carriers were more likely to develop lung cancer.

Effect of shRNA targeted against RhoA on proliferation and migration of human colonic cancer cells

OBJECTIVE

To study the effects of RhoA siRNA on the malignant phenotypes of human colorectal cancer cell line LoVo.

METHODS

The siRNA expression vector pGPU6/GFP/Neo-shRNA-RhoA targeting the mRNA of RhoA and vector pGPU6/GFP/Neo-NC (as a control) were constructed, and then transfected into LoVo cells. The expression of Survivin was detected by real-time fluorescent quantitative polymerase chain reaction and Western blot. The malignant phenotypes of transfected LoVo cells, including invasive activities and adhesive capabilities, were analyzed.

RESULTS

RhoA mRNA and protein level were decreased after the pshRNA-RhoA transfection. The cell adhesion rates significantly decreased in the cells transfected with pshRNA-RhoA. The migrating number of LoVo cells (26.5 ± 0.9) transfected with pshRNA-RhoA was also significantly decreased as compared with the control group (53.7 ± 1.4).

CONCLUSIONS

The sequence specific shRNA against RhoA constructed in the study can block the expression of RhoA in LoVo cell effectively and specifically; Blocking the expression of RhoA in LoVo cells transfected with pshRNA-RhoA can reduce their invasive and adhesive capabilities.

Anti-tumor activity of selective inhibitors of XPO1/CRM1-mediated nuclear export in diffuse malignant peritoneal mesothelioma: the role of survivin

Survivin, which is highly expressed and promotes cell survival in diffuse malignant peritoneal mesothelioma (DMPM), exclusively relies on exportin 1 (XPO1/CRM1) to be shuttled into the cytoplasm and perform its anti-apoptotic function. Here, we explored the efficacy of Selective Inhibitors of Nuclear Export (SINE), KPT-251, KPT-276 and the orally available, clinical stage KPT-330 (selinexor), in DMPM preclinical models. Exposure to SINE induced dose-dependent inhibition of cell growth, cell cycle arrest at G1-phase and caspase-dependent apoptosis, which were consequent to a decrease of XPO1/CRM1 protein levels and the concomitant nuclear accumulation of its cargo proteins p53 and CDKN1a. Cell exposure to SINE led to a time-dependent reduction of cytoplasmic survivin levels. In addition, after an initial accumulation, the nuclear protein abundance progressively decreased, as a consequence of an enhanced ubiquitination and proteasome-dependent degradation. SINE and the survivin inhibitor YM155 synergistically cooperated in reducing DMPM cell proliferation. Most importantly, orally administered SINE caused a significant anti-tumor effect in subcutaneous and orthotopic DMPM xenografts without appreciable toxicity. Overall, we have demonstrated a marked efficacy of SINE in DMPM preclinical models that may relay on the interference with survivin intracellular distribution and function. Our study suggests SINE-mediated XPO1/CRM1 inhibition as a novel therapeutic option for DMPM.

Survivin expression and serum levels in pancreatic cancer

BACKGROUND

Survivin, an inhibitor of apoptosis, is overexpressed in pancreatic ductal adenocarcinoma (PDAC). Its expression is known to be associated with poor clinical outcome. However, to our knowledge, there has been no study to characterize its usefulness as a serum marker for human pancreatic cancer. Furthermore, the relation between survivin expression and the serum level of survivin has not been widely studied in PDAC. We performed this study to investigate the expression and serum level of survivin in PDAC and its clinical significance as a prognostic factor.

METHODS

We performed immunohistochemical staining for survivin in formalin-fixed, paraffin-embedded blocks from 80 PDAC tissues. The serum level of survivin from the patients (n = 80) and age-matched healthy volunteers (n = 80) were analyzed by enzyme-linked immunosorbent assays (ELISAs) prior to surgical resection. Levels of expression were correlated with clinicopathological parameters.

RESULTS

Serum survivin concentrations were significantly elevated in patients with PDAC when compared with healthy sera (P < 0.001). High serum survivin levels were significantly associated with perineural invasion, venous invasion, lymph node status (N stage), cell differentiation, and recurrence but not with the tumor size, age, gender of the patients, or tumor location. The median overall survival time of the group with normal serum survivin levels was longer than that of the group with elevated serum survivin. The independent factors associated with overall survival were advanced pancreatic cancer and elevated serum survivin level. Of the 80 cases of PDAC, 65 (81.25 %) were positive for survivin expression. There were significant associations between survivin expression and perineural invasion, venous invasion, and lymph node status. A significant difference in overall survival was associated with survivin expression.

CONCLUSIONS

Patients with elevated serum survivin level and high survivin expression at diagnosis demonstrated a poor outcome. Detection of serum survivin or tissue survivin expression may predict the prognosis of patients with PDAC.

Repeated-measures implication of hepatocellular carcinoma biomarkers in living donor liver transplantation

Objective

Hepatocellular carcinoma (HCC) and its recurrence are major problems in living donor liver transplantation (LDLT). Several biomarkers have been used to investigate this event. We conducted a prospective controlled study to determine the activities of the basic fibroblast growth factor (FGF-2), survivin, Ki67, endostatin, and vascular endothelial growth factor (VEGF) in different conditions before, early after, and late after LDLT with and without HCC recurrence.

Methods

Fifty patients with virus-related HCC who underwent LDLT were enrolled in this 2-year cross-sectional study. During the study period, recurrent HCC was identified in 9 patients (study group, n = 9) and 41 patients (control group, n = 41) had no recurrence after LDLT. The mean time to HCC recurrence was 587.11 ± 398.64 days (range, 90–1352 days). Microvascular invasion (MVI) was found in 66.7% (6/9) of the recipients, as determined on pathological examination. The serum biomarkers were investigated by using enzyme-linked immunosorbent assay at the different LDLT stages.

Results

The serum levels of the biomarkers significantly correlated with LDLT and HCC recurrence in the repeated-measures analysis (F = 31.676, P = 0.000). Significant differences were observed in the effects of all biomarkers (F = 85.313, P = 0.000) and the time to HCC recurrence after LDLT (F = 3.178, P = 0.046). The biomarkers, ordered by the observed power of the test for HCC recurrence after LDLT, were FGF-2 (1.000) > survivin (0.999) > Ki67 (0.949) > endostatin (0.411) > VEGF (0.305).

Conclusions

Different biomarker activities may be implicated in the pathogenesis of HCC recurrence after LDLT. Oncogenes may not exist in the new graft but may still be present in the peripheral blood. The timing of HCC recurrence and impact of MVI in the explanted liver requires confirmation in larger studies with a longer follow-up.

MicroRNA-204 targets JAK2 in breast cancer and induces cell apoptosis through the STAT3/BCl-2/survivin pathway

MicroRNAs (miRNAs) have emerged as important regulators that potentially play critical roles in cancer cell biological processes. Previous studies have shown that miR-204 plays an important role in various human cancers. However, the underlying mechanisms of this microRNA in breast cancer remain largely unknown. In the present study, we investigated that miR-204 expression level was markedly reduced in both the human breast cancer tissue and cultured breast cancer cell lines (MCF-7, MDA-MB-231). Overexpression of miR-204 inhibited the proliferation and promoted the apoptosis in breast cancer cells, which were reversed by co-transfection of miR-204 inhibitor. We validated that Janus kinase 2 (JAK2), as a direct target of miR-204, is overexpressed in breast cancer. Knockdown of JAK2 suppressed cell viability and induced apoptosis in breast cancer cells. Moreover, the level of miR-204 is negatively correlated with p-STAT3 and anti-apoptotic genes BCl-2 and surviving in breast cancer. In conclusions, miR-204 targets JAK2 and suppressed JAK2 and p-JAK2 expression in breast cancer, which further inhibit the activation of STAT3, BCl-2 and survivin. These findings indicate that manipulation of miR-204 expression may represent a novel therapeutic strategy in the treatment of breast cancer.

Overexpression of CRM1: A Characteristic Feature in a Transformed Phenotype of Lung Carcinogenesis and a Molecular Target for Lung Cancer Adjuvant Therapy

Our previous study showed that chromosome region maintenance 1 (CRM1), a nuclear export receptor for various cancer-associated "cargo" proteins, was important in regulating lung carcinogenesis in response to a tobacco carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The objectives of this study are to comprehensively evaluate the significance of CRM1 in lung cancer development and investigate the therapeutic potential of targeting CRM1 for lung cancer treatment using both in vitro and in vivo models. We showed that CRM1 was overexpressed not only in lung tumor tissues from both lung cancer patients and mice treated with NNK but also in NNK-transformed BEAS-2B human bronchial epithelial cells. Furthermore, stable overexpression of CRM1 in BEAS-2B cells by plasmid vector transfection led to malignant cellular transformation. Moreover, a decreased CRM1 expression level in A549 cells by short hairpin siRNA transfection led to a decreased tumorigenic activity both in vitro and in nude mice, suggesting the potential to target CRM1 for lung cancer treatment. Indeed, we showed that the cytotoxic effects of cisplatin on A549 cells with CRM1 down-regulated by short hairpin siRNA were significantly increased, compared with A549 cells, and the cytotoxic effects of cisplatin became further enhanced when the drug was used in combination with leptomycin B, a CRM1 inhibitor, in both in vitro and in vivo models. Cancer target genes were significantly involved in these processes. These data suggest that CRM1 plays an important role in lung carcinogenesis and provides a novel target for lung cancer adjuvant therapy.

Nuclear survivin expression in small cell lung cancer

BACKGROUND/AIM

Little evidence exists regarding a relationship between survivin expression and prognosis in small cell lung cancer (SCLC). We investigated the relationship between survivin expression, clinical characteristics and prognosis in SCLC patients.

MATERIALS AND METHODS

We retrospectively reviewed medical records of study patients and analyzed their tumor sections using nuclear survivin labeling index (LI).

RESULTS

A significant correlation between nuclear survivin LI and clinical stage was found (p=0.012). In multivariate analysis, a significant association was found between survival and clinical stage (hazard ratio (HR)=2.09; 95 % confidence interval (CI)=1.08-4.31; p=0.027) but not between survival and nuclear survivin LI (HR=0.96; 95 % CI=0.91-1.02; p=0.2).

CONCLUSION

We did not find any positive relationship between nuclear survivin expression and survival in SCLC patients. Conversely, we found a positive relationship between clinical stage and nuclear survivin LI, which is considered to be useful in deciding treatment strategies.

Chimeric nucleolin aptamer with survivin DNAzyme for cancer cell targeted delivery

A chimeric aptamer-DNAzyme conjugate was generated for the first time using a nucleolin aptamer (NCL-APT) and survivin Dz (Sur_Dz) and exhibited the targeted killing of cancer cells. This proof of concept of using an aptamer for the delivery of DNAzyme can be applied to other cancer types to target survivin in cancer cells in a specific manner.

[Antibodies for detection of E/K amino acid substitution in 129 position of the survivin sequence]

Survivin is an oncofetal protein involved both in inhibiting of apoptosis and in cell cycle regulation. The functions of survivin are defined by its structural state. Due to nature polymorphism, survivin cancontain either E or K amino acid in 129 residue, and K129 is commonly acetylated. Only the protein having acetylated K129 tends to form dimeric structure. Thus, antibodies detecting the amino acid substitution can be a useful tool for structural and functional research of the protein. To obtain the antibodies specific to amino acid substitution E129/K129 peptide fragments overlapping 129 amino acid residue were synthesized, rabbits were immunized with the peptides and affinity purification of the antibodies on sepharose conjugated with the peptides was carried out. The data of ELISA and western blot showed that antibodies obtained were able to detect amino acid substitution E129/K129 in the recombinant and endogenous survivin.

25-O-acetyl-23,24-dihydro-cucurbitacin F induces cell cycle G2/M arrest and apoptosis in human soft tissue sarcoma cells

ETHNOPHARMACOLOGICAL RELEVANCE

Quisqualis indica is used in traditional Chinese medicine to treat cancer and related syndromes and also known for its anthelminthic effects.

AIM OF THE STUDY

Soft tissue sarcomas represent a rare group of malignant tumors that frequently exhibit chemotherapeutic resistance and increased metastatic potential. In this study, we evaluated the cytotoxic, apoptosis inducing and cell cycle arresting effects of 25-O-acetyl-23,24-dihydro-cucurbitacin F which has been isolated from leaves and twigs of Q. indica.

MATERIAL AND METHODS

The present study investigates the effects of 25-O-acetyl-23,24-dihydro-cucurbitacin F (1) on cell viability, cell cycle distribution, and apoptotic induction of three human sarcoma cell lines of various origins by using the CellTiter 96(®) AQueous One Solution Cell Proliferation Assay, flow cytometrical experiments, real-time RT-PCR, Western blotting, and the Caspase-Glo(®) 3/7 Assay

RESULTS

We could show that 1 reduced cell viability in a dose-dependent manner and arrested the cells at the G2/M interface. The accumulation of cells at the G2/M phase resulted in a significant decrease of the cell cycle checkpoint regulators cyclin B1, cyclin A, CDK1, and CDK2. Interestingly, 1 inhibited survivin expression significantly, which functions as a key regulator of mitosis and programmed cell death, and is overexpressed in many tumor types including sarcomas. Moreover, 1 induced apoptosis in liposarcoma and rhabdomyosarcoma cells caspase-3 dependently.

CONCLUSION

Our data strongly support 1 as a very interesting target for further investigation and development of novel therapeutics in sarcoma research.

Survivin over-expression is correlated with a poor prognosis in esophageal cancer patients

BACKGROUND

The prognostic role of survivin in esophageal cancer (EC) remains controversial. This meta-analysis aimed to clarify the association of survivin with survival in EC patients.

METHODS

Relevant studies published up to November 2014 were identified using PubMed and Embase. Only studies in which survivin was detected through immunohistochemical staining were included. STATA 12.0 was used in this meta-analysis.

RESULTS

A total of 9 studies, which comprised 610 patients, were included in the meta-analysis. The combined hazard ratio (HR) of 1.76 (95% CI, 1.40-2.21; P<0.001) suggests that survivin overexpression in EC patients was significantly associated with poor overall survival. Moreover, the results showed a significant relationship between overall survival and survivin expression was also displayed in studies with a non-Asian country (HR, 1.75; 95% CI, 1.30-2.35), patient number ≥ 50 (HR, 1.86; 95% CI, 1.57-2.20), the cut-off level ≥ 5% (HR, 1.43; 95% CI, 0.94-2.17) and the esophageal squamous cell carcinoma (HR, 1.82; 95% CI, 1.43-2.30). However, combined odds ratio of survivin indicated that survivin overexpression has no correlation with stage, grade of differentiation, lymph node status, depth of invasion and distant metastasis of EC (P>0.05).

CONCLUSION

Survivin overexpression is associated with poor prognosis in EC patients.

Clinical and prognostic significance of survivin, AKT and VEGF in primary mucosal oral melanoma

AIM

To investigate survivin, AKT and VEGF expression in primary mucosal oral melanoma and explore their correlation with clinicopathological features and prognosis.

PATIENTS AND METHODS

Twenty malignant primary oral melanomas were immunostained with antibodies against survivin, AKT, VEGF, CD34. Histological parameters and disease-specific survival were related to marker expressions.

RESULTS

Survivin localization was both nuclear and cytoplasmic with a higher expression of nuclear survivin. High melanocyte survivin expression significantly correlated with higher thickness of primary melanoma. A significant positive correlation was found between melanocyte survivin and phospho Akt and VEGF expression. Survivin was significantly associated with the presence of metastasis. High melanocyte survivin and high endothelial VEGF expression were inversely correlated to both overall and disease-specific 5-year survival.

CONCLUSION

Survivin, via AKT and VEGF, seems to play an important role in oral melanoma and could represent an important prognostic marker of melanoma progression.

EXPRESSION AND CLINICAL SIGNIFICANCE OF APOPTOSIS-ASSOCIATED PROTEINS SURVIVIN AND LIVIN IN CONDYLOMA ACUMINATUM

The objective of the present study was to explore the expression and significance of survivin and Livin in lesions of Condyloma acuminatum (CA). Streptavidin-peroxidase (SP) immunohistochemistry method was used to measure the expression of survivin, Livin and Ki-67 in 48 cases of CA and 25 cases of normal foreskin tissues. The positive expression rates of survivin, Livin and Ki-67 were 72.91% (35/48), 77.08% (37/48) and 85.42% (41/48) in CA tissues, and 4% (1/25), 4% (5/25) and 60% (15/25) in the control group, respectively. The expression intensity of survivin, Livin and Ki-67 in CA tissues (++ ~ +++) was significantly higher than that in the normal control group (- ~ ++). There were significant differences (P <0.05) both in the positive rates and the expression intensity of survivin, Livin and Ki-67 between the two groups. There was positive correlation between the expression of survivin and Livin in CA group (P < 0.01); the expressions of survivin and Ki-67 were positively correlated with each other (P < 0.01); Livin and Ki-67 expressions were positively correlated with each other (P < 0.01). There were over-expressions and excessive proliferations of survivin and Livin in CA tissues, and apoptosis suppressors survivin and Livin were correlated with CA.

BAP1 has a survival role in cutaneous melanoma

Although the pattern of BAP1 inactivation in ocular melanoma specimens and in the BAP1 cutaneous melanoma (CM)/ocular melanoma predisposition syndrome suggests a tumor suppressor function, the specific role of this gene in the pathogenesis of CM is not fully understood. We thus set out to characterize BAP1 in CM and discovered an unexpected pro-survival effect of this protein. Tissue and cell lines analysis showed that BAP1 expression was maintained, rather than lost, in primary melanomas compared with nevi and normal skin. Genetic depletion of BAP1 in melanoma cells reduced proliferation and colony-forming capability, induced apoptosis, and inhibited melanoma tumor growth in vivo. On the molecular level, suppression of BAP1 led to a concomitant drop in the protein levels of survivin, a member of anti-apoptotic proteins and a known mediator of melanoma survival. Restoration of survivin in melanoma cells partially rescued the growth-retarding effects of BAP1 loss. In contrast to melanoma cells, stable overexpression of BAP1 into immortalized but non-transformed melanocytes did suppress proliferation and reduce survivin. Taken together, these studies demonstrate that BAP1 may have a growth-sustaining role in melanoma cells, but that its impact on ubiquitination underpins a complex physiology, which is context and cell dependent.

Differential effect of phosphorylation-defective survivin on radiation response in estrogen receptor-positive and -negative breast cancer

Survivin is a key member of the inhibitor of apoptosis protein family, and is considered a promising therapeutic target due to its universal overexpression in cancers. Survivin is implicated in cellular radiation response through its role in apoptosis, cell division, and DNA damage response. In the present study, analysis of publically available data sets showed that survivin gene expression increased with breast cancer stage (p < 0.00001) and was significantly higher in estrogen receptor-negative cancers as compared to estrogen receptor-positive cancers (p = 9e-46). However, survivin was prognostic in estrogen receptor-positive tumors (p = 0.03) but not in estrogen receptor-negative tumors (p = 0.28). We assessed the effect of a survivin dominant-negative mutant on colony-formation (2D) and mammosphere-formation (3D) efficiency, and radiation response in the estrogen receptor-positive MCF7 and estrogen receptor-negative SUM149 breast cancer cell lines. The colony-formation efficiency was significantly lower in the dominant-negative survivin-transduced cells versus control MCF7 cells (0.42 vs. 0.58, p < 0.01), but it was significantly higher in dominant-negative population versus control-transduced SUM149 cells (0.29 vs. 0.20, p < 0.01). A similar, non-significant, trend in mammosphere-formation efficiency was observed. We compared the radiosensitivity of cells stably expressing dominant-negative survivin with their controls in both cell lines under 2D and 3D culture conditions following exposure to increasing doses of radiation. We found that the dominant-negative populations were radioprotective in MCF7 cells but radiosensitive in SUM149 cells compared to the control-transduced population; further, Taxol was synergistic with the survivin mutant in SUM149 but not MCF7. Our data suggests that survivin modulation influences radiation response differently in estrogen receptor-positive and estrogen receptor-negative breast cancer subtypes, warranting further investigation.

Sp1 and c-Myc modulate drug resistance of leukemia stem cells by regulating survivin expression through the ERK-MSK MAPK signaling pathway

BACKGROUND

Acute myeloid leukemia (AML) is initiated and maintained by a subset of self-renewing leukemia stem cells (LSCs), which contribute to the progression, recurrence and therapeutic resistance of leukemia. However, the mechanisms underlying the maintenance of LSCs drug resistance have not been fully defined. In this study, we attempted to elucidate the mechanisms of LSCs drug resistance.

METHODS

We performed reverse phase protein arrays to analyze the expression of anti-apoptotic proteins in the LSC-enriched leukemia cell line KG-1a. Immuno-blotting, cell viability and clinical AML samples were evaluated to verify the micro-assay results. The characteristics and transcriptional regulation of survivin were analyzed with the relative luciferase reporter assay, mutant constructs, chromatin immuno-precipitation (ChIP), quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR), and western blotting. The levels of Sp1, c-Myc, phospho-extracellular signal-regulated kinase (p-ERK), phospho-mitogen and stress-activated protein kinase (p-MSK) were investigated in paired CD34+ and CD34- AML patient samples.

RESULTS

Survivin was highly over-expressed in CD34 + CD38- KG-1a cells and paired CD34+ AML patients compared with their differentiated counterparts. Functionally, survivin contributes to the drug resistance of LSCs, and Sp1 and c-Myc concurrently regulate levels of survivin transcription. Clinically, Sp1 and c-Myc were significantly up-regulated and positively correlated with survivin in CD34+ AML patients. Moreover, Sp1 and c-Myc were further activated by the ERK/MSK mitogen-activated protein kinase (MAPK) signaling pathway, modulating survivin levels.

CONCLUSION

Our findings demonstrated that ERK/MSK/Sp1/c-Myc axis functioned as a critical regulator of survivin expression in LSCs, offering a potential new therapeutic strategy for LSCs therapy.