High expression of survivin predicts poor prognosis in esophageal squamous cell carcinoma following radiotherapy. Tumour Biol. 2011;32:1147-1153. [PMID: 21826474 DOI: 10.1007/s13277-011-0217-y]

Functional Compartmentalization of HSP60-Survivin Interaction between Mitochondria and Cytosol in Cancer Cells

Heat shock protein 60 (HSP60) and survivin reside in both the cytosolic and mitochondrial compartments under physiological conditions. They can form HSP60-survivin complexes through protein–protein interactions. Their expression levels in cancer tissues are positively correlated and higher expression of either protein is associated with poor clinical prognosis. The subcellular location of HSP60-survivin complex in either the cytosol or mitochondria is cell type-dependent, while the biological significance of HSP60-survivin interaction remains elusive. Current knowledge indicates that the function of HSP60 partly rests on where HSP60-survivin interaction takes place. HSP60 has a pro-survival function when binding to survivin in the mitochondria through interacting with other factors such as CCAR2 and p53. In response to cell death signals, mitochondrial survivin functions through preventing procaspase activation. Degradation of cytosolic survivin leads to the loss of mitochondrial membrane potential and aberrant mitosis processes. On the other hand, HSP60 release from mitochondria to cytosol upon death stimuli might exert a pro-death function, either through stabilizing Bax, enhancing procaspase-3 activation, or increasing protein ubiquitination. Combining the knowledge of mitochondrial HSP60-survivin complex function, cytosolic survivin degradation effect, and pro-death function upon mitochondria release of HSP60, a hypothetical scenario for HSP60-survivin shuttling upon death stimuli is proposed.

The effect of polymorphisms in the promoter of the BIRC5 gene on the risk of oesophageal squamous cell carcinoma and patient’s outcomes

Baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5) is an inhibitor of apoptosis proteins and plays a key role in apoptosis or programmed cell death. In the present study, we evaluated the effect of BIRC5 gene polymorphisms on the risk of developing oesophageal squamous cell carcinoma (ESCC) and patients’ outcomes in a high-incidence population from northern China. A population-based case-control study was performed in 597 ESCC patients and 597 control subjects.Survival data were available for 211 patients who received platinum-based chemotherapy after surgery. Five polymorphisms (-31 C>G, -241 C>T, -625 G>C, -644 T>C and -1547 A>G) in the promoter of the BIRC5 gene were genotyped by the polymerase chain reaction-ligase detection reaction (PCR-LDR) method. Compared with the -31 CC genotype, the -31 CG/GG genotype of -31 C>G single nucleotide polymorphism (SNP) was associated with a significant elevated risk of ESCC [adjusted odds ratio (OR) = 1.40, 95% confidence interval (CI) = 1.07–1.84]. Interestingly, this association was stronger among females, younger patients and non-smokers in stratified analyses (adjusted OR = 1.72, 95% CI = 1.07–2.75; adjusted OR = 1.61, 95% CI = 1.10–2.36; adjusted OR = 1.80, 95% CI = 1.26–2.58, respectively]. Survival analyses showed that the T allele of -241 C>T SNP was associated with poor prognosis [hazard ratio (HR) = 2.99, 95% CI = 1.09–8.19) and that the C allele of -625 G>C SNP was associated with good prognosis (HR = 0.62, 95% CI = 0.38–0.99) in ESCC patients. The -31 C>G polymorphism may be involved in the development of ESCC, and the -241 C>T and -625 G>C polymorphisms may be useful prognostic markers for ESCC.

Inhibition of survivin enhances radiosensitivity of esophageal cancer cells by switching radiation-induced senescence to apoptosis

Purpose

Strategies to increase radiosensitivity are urgently needed. Combining radiosensitizing reagents with radiotherapy could improve the outcome of cancer treatment. Some preclinical studies showed that sepantronium bromide (YM155) could sensitize cancer cells to radiation by inhibiting the survivin protein. In this study, we try to investigate the function of YM155 on radiosensitivity of esophageal squamous cell carcinoma (ESCC) cells.

Materials and methods

ESCC cell lines were treated with radiation and YM155, and the radiation efficacy was evaluated by cell counting kit-8 assay and clonogenic survival assay. Cell senescence was measured by senescence-associated β-galactosidase staining. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, fluorescein isothiocyanate-labeled Annexin V/propidium iodide assay, and poly ADP-ribose polymerase cleavage were used to detect apoptosis. KYSE150 xenografts model was used to test the efficacy of radiation combined with YM155.

Results

YM155 could inhibit the upregulation of survivin induced by radiation in all ESCC cell lines, but the efficacy of radiosensitization varied in different cell lines. Radiation-induced senescence in KYSE150 and KYSE410 cells, and the combination with YM155 inhibited senescence and promoted apoptosis of ESCC cells, thereby enhancing radiosensitivity. Combination with YM155 and radiation delayed the growth of KYSE150 xenografts in nude mice by switching radiation-induced senescence to apoptosis. When p21 was inhibited in KYSE150 cells, radiation did not induce senescence, and the radiosensitization of YM155 was also attenuated. In KYSE510 and KYSE180 cells, radiation did not induce senescence, and YM155 could not enhance the radiosensitivity.

Conclusion

Our results suggest a new mechanism that YM155 might sensitize ESCC cells to radiation by switching radiation-induced senescence to apoptosis. The major determinant of radiosensitization by YM155 might be the induction of senescence by radiation.

Clinicopathological and functional implications of the inhibitor of apoptosis proteins survivin and XIAP in esophageal cancer

Based on their overexpression and important roles in progression and therapy-resistance in malignant diseases, the inhibitor of apoptosis protein family (IAP) members, survivin and X-linked inhibitor of apoptosis protein (XIAP), represent attractive candidates for targeted therapy. The present study investigated the prognostic and biological relevance of survivin and XIAP in esophageal squamous-cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC). Survivin and XIAP expression was analyzed by immunohistochemistry using tissue microarrays containing 120 ESCC and 90 EAC samples as well as the corresponding non-neoplastic esophageal mucosa samples. IAP expression levels were then correlated to clinicopathological parameters and overall survival to identify any associations. In addition, esophageal cancer cell lines were treated with the survivin inhibitor YM155, and the XIAP inhibitors Birinapant and GDC-0152 in vitro. Survivin and XIAP expression were significantly increased in EAC and ESCC when compared with tumor-adjacent mucosa. In patients with ESCC XIAP expression was associated with female gender and advanced tumor stages, and nuclear survivin expression was associated with poor grading. High XIAP expression was identified as an independent negative prognostic marker in ESCC. By contrast, XIAP inhibitors did not affect cancer cell viability in vitro, and the small molecule survivin inhibitor YM155 significantly reduced cell viability and proliferation in esophageal cancer cell lines. Western blot analysis revealed a dose dependent decrease of survivin accompanied by an increased poly (adenosine diphosphate-ribose) polymerase cleavage following YM155 treatment. These findings underline the potential role of survivin and XIAP in the oncogenesis of esophageal cancer and provide a rationale for future clinical studies investigating the therapeutic efficacy of IAP directed therapies in patients with esophageal cancer.

The Role of cIAP1 and XIAP in Apoptosis Induced by Tumor Necrosis Factor Alpha in Esophageal Squamous Cell Carcinoma Cells

BACKGROUND

The inhibitor of apoptosis protein (IAP) family are reported to play important roles in cancer cells evading apoptosis. However, the significance of their expression in human esophageal squamous cell carcinoma (ESCC) cells remains uncertain.

AIMS

The present study aimed to investigate the role of the IAP family members in tumor necrosis factor-α (TNF-α)-induced apoptosis of human ESCC cells.

METHODS

Five human ESCC cell lines were pretreated with TNF-α, cycloheximide (CHX, protein synthesis inhibitor), epoxomicin (proteasome inhibitor). Apoptosis assay and protein study with Western blot testing were conducted. Knockdown experiments with IAP siRNA were conducted, and the effect on cell apoptosis was analyzed.

RESULTS

Significant apoptosis was induced in five ESCC cell lines by TNF-α plus CHX stimulation, but not when treated with TNF-α or CHX alone. The protein expression levels of cIAP1 and XIAP were decreased by treatment with TNF-α in the presence of CHX, and the degree of cIAP1 and XIAP expression decrease was correlated with sensitivity to TNF-α plus CHX-induced apoptosis. Epoxomicin suppressed TNF-α plus CHX-induced degradation of survivin, cIAP1, and XIAP, in addition to apoptosis. A caspase inhibitor (z-VAD-fmk) suppressed TNF-α plus CHX-induced apoptosis, but did not suppress degradation of survivin, cIAP1, and XIAP. Furthermore, cIAP1 or XIAP siRNA transfected cells underwent apoptosis in response to treatment with TNF-α alone. Double knockdown of both genes resulted in further increased apoptosis.

CONCLUSION

cIAP1 and XIAP play an essential role in the resistance of ESCC cells against apoptosis.

Oroxylin a could be a Promising Radiosensitizer for Esophageal Squamous Cell Carcinoma by Inducing G2/M Arrest and Activating Apoptosis

To evaluate the radiosensitization of Oroxylin A on esophageal carcinoma cell as well as the optimal scheduling of Oroxylin A and radiotherapy (RT). Cell proliferation was estimated by a CCK8 assay. Radiosensitization was evaluated by a clonogenic survival assay. The progressions of Cell apoptosis and Cell cycle were investigated by flow cytometry. Expressions of survivin and cell cycle regulators were evaluated by Western blot analysis. A dose-dependent cell survival reduction was found in response to radiation with or without Oroxylin A. The apoptosis rates were remarkably dose-dependent higher in combination groups than in either Oroxylin A or radiation alone group. Besides, Oroxylin A could obviously radiosensitize ESCC cells by arresting tumor cells in G2/M phase and regulating cyclin B1 and Cdc 2 protein expression. Oroxylin A could be a promising radiosensitizer for esophageal squamous cell carcinoma by inducing G2/M phase blocking and activating cell apoptosis.

YM155, a survivin suppressant, triggers PARP-dependent cell death (parthanatos) and inhibits esophageal squamous-cell carcinoma xenografts in mice

Here we demonstrated that sepantronium bromide (YM155), a survivin suppressant, inhibited esophageal squamous-cell carcinoma (ESCC) growth in mice bearing human ESCC xenografts without affecting body weight. In cell culture, YM155 decreased survivin levels and caused PARP-1 activation, poly-ADP polymer formation, and AIF translocation from the cytosol to the nucleus. Genetic knockdown of PARP-1 or AIF abrogated YM155-induced parthanatos cell death. Furthermore, FOS, JUN and c-MYC gene transcription, which is stimulated by activated PARP-1, was increased following YM155 treatment. Our data demonstrate that YM155 did not trigger apoptosis, but induced parthanatos, a cell death dependent on PARP-1 hyper-activation, and support clinical development of YM155 in ESCC.

Survivin activates NF‑κB p65 via the IKKβ promoter in esophageal squamous cell carcinoma

Survivin and transcription factor p65 (NF‑κB p65) participate in the progression of esophageal squamous cell carcinoma (ESCC). However, the mechanism of NF‑κB p65 activation in ESCC remains to be elucidated. The aim of the present study was to investigate the role of survivin in the activation of NF‑κB p65 in ESCC. The expression levels of survivin, NF‑κB p65, inhibitor of nuclear factor κB kinase subunit α (IKKα) and inhibitor of nuclear factor κB kinase subunit β (IKKβ) were detected in ESCC tissue samples. Eca109 and KYSE150 cells were cultured and survivin activity was modulated via transfection with an overexpression plasmid, a small hairpin RNA plasmid and a specific inhibitor. Quantitative reverse transcription-polymerase chain reaction and western blotting assays were conducted to assess the effects of survivin on the expression levels of IKKα, IKKβ and NF‑κB p65. Cell cycle and apoptosis assays were conducted to detect surviving-dependent cellular behavior changes. In addition, the luciferase reporter gene assay and chromatin immunoprecipitation assay were conducted to determine the genomic sites responsible for surviving-induced activation of NF‑κB p65. The present study demonstrated that the expression of survivin is positively correlated with IKKα and IKKβ in ESCC tissues. Survivin affected the mRNA and protein expression levels of IKKα, IKKβ, and NF‑κB p65 in Eca109 and KYSE150 cells. Furthermore, survivin increased the transcriptional activity of the IKKβ promoter and bound to the IKKβ promoter region in the Eca109 cells. Downregulation of survivin arrested the cell cycle at the G2/M phase and induced apoptosis. Results of the present study suggest that survivin activates NF‑κB p65 in Eca109 cells via binding to the IKKβ promoter region and upregulating IKKβ promoter transcriptional activity. Survivin overexpression activates NF‑κB p65, which is important in the acquisition and maintenance of the oncogenic characteristics of ESCC.

Far upstream element-binding protein 1 (FUBP1) is a potential c-Myc regulator in esophageal squamous cell carcinoma (ESCC) and its expression promotes ESCC progression

The human far upstream element (FUSE) binding protein 1 (FUBP1) belongs to an ancient family which is required for proper regulation of the c-Myc proto-oncogene. Although c-Myc plays an important role in development of various carcinomas, the relevance of FUBP1 and their contribution to esophageal squamous cell carcinoma (ESCC) development remain unclear. In this study, we aimed to investigate the relationship between FUBP1 and c-Myc as well as their contribution to ESCC development. Western blot and immunohistochemical analyses were performed to evaluate FUBP1 expression. Coimmunoprecipitation analysis was performed to explore the correlation between FUBP1 and c-Myc in ESCC. In addition, the role of FUBP1 in ESCC proliferation was studied in ESCC cells through knocking FUBP1 down. The regulation of FUBP1 on proliferation was confirmed by Cell Counting Kit-8 (CCK-8) assay, flow cytometric assays, and clone formation assays. The expressions of FUBP1 and c-Myc were both upregulated in ESCC tissues. In addition to correlation between expression of FUBP1 and tumor grade, we also confirmed the correlation of FUBP1, c-Myc, and Ki-67 expression by twos. Moreover, upregulation of FUBP1 and c-Myc in ESCC was associated with poor survival. FUBP1 was confirmed to activate c-Myc in ESCC tissues and cells. FUBP1 was demonstrated to promote proliferation of ESCC cells. Moreover, downregulation of both FUBP1 and c-Myc was confirmed to inhibit proliferation of ESCC cells. Our results indicated that FUBP1 may potentially stimulate c-Myc expression in ESCC and its expression may promote ESCC progression.

Survivin expression in lung cancer: Association with smoking, histological types and pathological stages

Survivin is expressed in the nucleus and/or cytoplasm of various malignant cells. Nuclear survivin is critical for the completion of mitosis, while cytoplasmic survivin functions as an inhibitor of apoptosis. The expression of survivin has been reported to be associated with the aggressiveness of certain types of cancer. The present study examined the association between cigarette smoking history and the expression of survivin and Ki-67 in lung adenocarcinomas of pathological (p) stages I, II and III. The expression of survivin and Ki-67 in adenocarcinomas was also compared with that of other p-stage I lung cancers, including squamous cell carcinoma (SqCC), large cell neuroendocrine carcinoma (LCNEC) and small cell carcinoma (SmCCs), of patients with a smoking history. In adenocarcinomas at p-stage I, labeling indices (LIs) of nuclear survivin and Ki-67 were significantly higher in tissue samples from smokers than those from non-smokers; however, the nuclear survivin and Ki-67 LIs in p-stage II and III adenocarcinomas from non-smokers and smokers were similar to those in p-stage I adenocarcinomas of smokers. The nuclear survivin and Ki-67 LIs in adenocarcinomas of smokers at p-stage I were lower than those in SqCCs, LCNECs and SmCCs of smokers at the same stage. Smokers with adenocarcinoma also exhibited a higher survival rate compared with that of smokers with SqCCs, LCNECs and SmCCs. The present results indicated that a history of smoking is associated with increased nuclear survivin and Ki-67 expression in lung adenocarcinomas of p-stage I, but not p-stages II or III. In addition it was revealed that, in smokers, the nuclear survivin and Ki-67 expression in p-stage I adenocarcinomas was lower than that of other p-stage I lung cancer types, and was associated with an enhanced survival rate. In conclusion, smoking is associated with the histogenesis of lung adenocarcinoma but not with the development of lung adenocarcinoma, based on the nuclear expression levels of Ki-67 and survivin.

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.

High expression of SGTA in esophageal squamous cell carcinoma correlates with proliferation and poor prognosis

Receptor tyrosine kinases (RTKs) expression and the growth factor such as platelet-derived growth factor (PDGF) and their receptors have been considered relevant in the process of angiogenesis and dissemination in esophageal squamous cell carcinoma (ESCC). Small glutamine-rich tetratricopeptide repeat-containing protein alpha (SGTA) downstream of RTK signaling was a critical regulator of PDGF receptors (PDGFR) stability. The aim of the present study was to examine the expression of SGTA and to elucidate its clinicopathologic significance in ESCC. Immunohistochemistry and western blot analysis were performed for SGTA in ESCC samples. SGTA was up-regulated in ESCC as compared with the adjacent normal tissue. High expression of SGTA was associated with tumor grade (P < 0.01), and SGTA was positively correlated with proliferation marker Ki-67 (P < 0.05). Univariate analysis showed that SGTA expression did has a remarkable prediction for poor prognosis (P = 0.016). Knockdown or overexpression of SGTA affected ESCC cells proliferation and cell cycle. Additionally, after ESCC cells silenced for SGTA were treated with cisplatin (an anti-ESCC agent), the cell growth was down-regulated. These findings suggested that SGTA was involved in the pathogenesis of ESCC and might indicate a poor prognosis for ESCC patients.

Small-molecule survivin inhibitor YM155 enhances radiosensitization in esophageal squamous cell carcinoma by the abrogation of G2 checkpoint and suppression of homologous recombination repair

Background

Survivin is overexpressed in cancer cells and plays a crucial role in apoptosis evasion. YM155, a small-molecule inhibitor of survivin, could enhance the cytotoxicity of various DNA-damaging agents. Here, we evaluated the radiosensitizaion potential of YM155 in human esophageal squamous cell carcinoma (ESCC).

Methods

Cell viability was determined by CCK8 assay. The radiosensitization effect of YM155 was evaluated by clonogenic survival and progression of tumor xenograft. Cell cycle progression was determined by flow cytometric analysis. Radiation-induced DNA double strand break (DSB) and homologous recombination repair (HRR) were detected by the staining of γ-H2AX and RAD51, respectively. Expression of survivin and cell cycle regulators was detected by Western blot analysis.

Results

YM155 induced radiosensitization in ESCC cell lines Eca109 and TE13, associated with the abrogation of radiation induced G₂/M checkpoint, impaired Rad51 focus formation, and the prolongation of γ-H2AX signaling. G₂/M transition markers, including the activation of cyclinB1/Cdc2 kinase and the suppression of Cdc2 Thr14/Tyr15 phosphorylation were induced by YM155 in irradiated cells. The combination of YM155 plus irradiation delayed the growth of ESCC tumor xenografts to a greater extent compared with either treatment modality alone.

Conclusions

Our findings suggest that the abrogation of G₂ checkpoint and the inhibition of HRR contribute to radiosensitization by YM155 in ESCC cells.

Upregulation of SYF2 in esophageal squamous cell carcinoma promotes tumor cell proliferation and predicts poor prognosis

SYF2, also known as CCNDBP1-interactor or p29, is reported in pre-mRNA splicing and cell cycle progression. However, the role of SYF2 in esophageal squamous cell carcinoma (ESCC) development remains elusive. In the present study, Western blot and immunohistochemistry assays demonstrated that SYF2 was overexpressed in ESCC tumor tissues and cell lines. In addition, immunohistochemistry analysis revealed that SYF2 expression was positively correlated with tumor grade and predicted poor prognosis of ESCC. In vitro studies using serum starvation-refeeding experiment and SYF2-siRNA transfection assay demonstrated that SYF2 expression promoted proliferation of ESCC cells, while SYF2 knockdown led to decreased cell growth rate and colony formation resulted from growth arrest of cell cycle at G0/G1 phase. Furthermore, our results indicated that SYF2 can down-regulate the sensitivity of ESCC cells for cisplatin. Our findings for the first time supported that SYF2 might play an important role in the regulation of ESCC proliferation and would provide a novel therapeutic strategy against human ESCC.

Monitoring survivin expression in cancer: implications for prognosis and therapy

Survivin, a member of the inhibitor of apoptosis protein family, is one of the most cancer-specific proteins identified to date. Survivin expression is low or undetectable in most adult tissues, but, alternatively, is overexpressed in a large number of tumors. This multifunctional protein is recognized as a key regulator in apoptosis, proliferation and angiogenesis in the tumor environment. Several studies have shown a correlation between survivin upregulation and poor cancer prognosis, and, as expected, its downregulation or inactivation leads to inhibition of tumor growth. Therefore, survivin has attracted increasing attention both as a potential cancer biomarker and as a new target for anticancer therapies. This review summarizes and discusses survivin expression and its potential as a prognostic and diagnostic biomarker in different types of tumors, as well as provides an overview of the current therapeutic challenges of targeting survivin as a treatment strategy.

Enhancement of Gemcitabine sensitivity in pancreatic adenocarcinoma by novel exosome-mediated delivery of the Survivin-T34A mutant

Background

Current therapeutic options for advanced pancreatic cancer have been largely disappointing with modest results at best, and though adjuvant therapy remains controversial, most remain in agreement that Gemcitabine should stand as part of any combination study. The inhibitor of apoptosis (IAP) protein Survivin is a key factor in maintaining apoptosis resistance, and its dominant-negative mutant (Survivin-T34A) has been shown to block Survivin, inducing caspase activation and apoptosis.

Methods

In this study, exosomes, collected from a melanoma cell line built to harbor a tetracycline-regulated Survivin-T34A, were plated on the pancreatic adenocarcinoma (MIA PaCa-2) cell line. Evaluation of the presence of Survivin-T34A in these exosomes followed by their ability to induce Gemcitabine-potentiative cell killing was the objective of this work.

Results

Here we show that exosomes collected in the absence of tetracycline (tet-off) from the engineered melanoma cell do contain Survivin-T34A and when used alone or in combination with Gemcitabine, induced a significant increase in apoptotic cell death when compared to Gemcitabine alone on a variety of pancreatic cancer cell lines.

Conclusion

This exosomes/Survivin-T34A study shows that a new delivery method for anticancer proteins within the cancer microenvironment may prove useful in targeting cancers of the pancreas.

Over-expression of survivin and VEGF in small-cell lung cancer may predict the poorer prognosis

The expression of survivin, an inhibitor of apoptosis can be seen in most tumors and is correlated with the angiogenic factor vascular endothelial growth factor (VEGF). But little is known about their contribution in small-cell lung cancer (SCLC). This study was designed to investigate the expression of survivin and VEGF in SCLC, and to explore their correlation with clinical-pathological feature and prognosis. Forty-five patients with pathological histology of SCLC were entered into this study. Forty-five cases of matched adjacent non-tumor samples and 10 samples of operated patients with benign lung tumor were also included as control. The expression of survivin and VEGF was detected by immunohistochemistry (IHC, SP). These two sets of data were processed and tested for correlation with major patients' characteristics, and overall survival. The correlations between survivin and VEGF expressions and the clinical-pathological features were evaluated by chi-square test. The correlation between survivin and VEGF expressions was analyzed by Spearman's rank correlation test; the overall survival was analyzed by the Kaplan-Meier method; and the relationship between clinical and pathological features and overall survival was analyzed by the Cox proportional hazard models. Positive expression rate of survivin and VEGF was significantly higher in SCLC than those of adjacent non-tumor tissues and benign lung tumor tissues (73.3 vs. 15.6 vs. 0 %, P < 0.05) and (75.6 vs. 20 vs. 0 %, P < 0.05), respectively. Survivin and VEGF expressions were significantly associated with lymph node metastasis (P = 0.003, 0.011) and clinical stage (P = 0.006, 0.021). The expression of survivin was significantly coincident with the expression of VEGF (r = 0.644, P = 0.000). The median overall survival in survivin positive group and VEGF positive group was significantly shorter than those in survivin negative and VEGF negative group, respectively (log-rank P = 0.000). Moreover, multivariate analysis showed that survivin expression (HR 0.224; 95 % CI 0.074-0.675; P = 0.008) and VEGF expression (HR 0.172; 95 % CI 0.054-0.559; P = 0.003) were statistically independent predictive factors of poorer prognosis for SCLC patients. Our results indicated that survivin and VEGF were over-expressed in small-cell lung cancer, each of them may be an independent poor prognostic factor.

Prognostic value and targeted inhibition of survivin expression in esophageal adenocarcinoma and cancer-adjacent squamous epithelium

BACKGROUND

Survivin is an inhibitor of apoptosis and its over expression is associated with poor prognosis in several malignancies. While several studies have analyzed survivin expression in esophageal squamous cell carcinoma, few have focused on esophageal adenocarcinoma (EAC) and/or cancer-adjacent squamous epithelium (CASE). The purpose of this study was 1) to determine the degree of survivin up regulation in samples of EAC and CASE, 2) to evaluate if survivin expression in EAC and CASE correlates with recurrence and/or death, and 3) to examine the effect of survivin inhibition on apoptosis in EAC cells.

METHODS

Fresh frozen samples of EAC and CASE from the same patient were used for qRT-PCR and Western blot analysis, and formalin-fixed, paraffin-embedded tissue was used for immunohistochemistry. EAC cell lines, OE19 and OE33, were transfected with small interfering RNAs (siRNAs) to knockdown survivin expression. This was confirmed by qRT-PCR for survivin expression and Western blot analysis of cleaved PARP, cleaved caspase 3 and survivin. Survivin expression data was correlated with clinical outcome.

RESULTS

Survivin expression was significantly higher in EAC tumor samples compared to the CASE from the same patient. Patients with high expression of survivin in EAC tumor had an increased risk of death. Survivin expression was also noted in CASE and correlated with increased risk of distant recurrence. Cell line evaluation demonstrated that inhibition of survivin resulted in an increase in apoptosis.

CONCLUSION

Higher expression of survivin in tumor tissue was associated with increased risk of death; while survivin expression in CASE was a superior predictor of recurrence. Inhibition of survivin in EAC cell lines further showed increased apoptosis, supporting the potential benefits of therapeutic strategies targeted to this marker.

Smac mimetic compound LCL161 sensitizes esophageal carcinoma cells to radiotherapy by inhibiting the expression of inhibitor of apoptosis protein

Currently, unresectable esophageal squamous cell carcinoma (ESCC) is primarily treated by chemoradiotherapy. However, the outcome has not improved significantly due to radioresistance of cancer cells. This study aimed to determine the radiosensitizing effect of LCL161, a novel second mitochondrial-derived activator of caspase (Smac) mimetic, in ESCC cells. ESCC cell lines were treated with LCL161 or radiation, alone or in combination. Cell proliferation was detected by MTT assay. Radiosensitization was evaluated by clonogenic survival assay. Cell apoptosis was detected by flow cytometry. The results showed that LCL161 potently sensitized ESCC cells to radiation with a sensitization enhancement ratio of 1.4-2.0. LCL161 increased radiation-induced DNA double-stranded breaks and promoted the apoptosis of ESCC cells, which could be abrogated by a pan-caspase inhibitor z-VAD-FMK. Furthermore, LCL161 decreased the level of cIAP1 in ESCC cells in a dose-dependent manner and synthesized with irradiation to promote the activation of caspase 8 and the upregulation of TNFα expression in ESCC cells. In conclusion, LCL161 acts as a strong radiosensitizer in human esophageal cancer cells by inhibiting the expression of cIAP1 and promoting the activation of caspase 8, leading to enhanced apoptosis.

Generation of CTL responses against pancreatic cancer in vitro using dendritic cells co-transfected with MUC4 and survivin RNA

Pancreatic cancer (PC) is one of the most devastating human malignancies without effective therapies. Tumor vaccine based on RNA-transfected dendritic cells (DCs) has emerged as an alternative therapeutic approach for a variety of human cancers including advanced PC. In the present study we compared the cytotoxic T lymphocyte (CTL) responses against PC cells in vitro, which were induced by DCs co-transfected with two mRNAs of tumor associated-antigens (TAA) MUC4 and survivin, versus DCs transfected with a single mRNA encoding either MUC4 or survivin. DCs co-transfected with two TAA mRNAs were found to induce stronger CTL responses against PC target cells in vitro, compared with the DCs transfected with a single mRNA. Moreover, the antigen-specific CTL responses were MHC class I-restricted. These results provide an experimental foundation for further clinical investigations of DC vaccines encoding multiple TAA epitopes for metastatic PC.

Strong expression of survivin is associated with positive response to radiotherapy and improved overall survival in head and neck squamous cell carcinoma patients

Head and neck squamous cell carcinoma (HNSCC) is a malignancy that is associated with severe mortality despite advances in therapy. Today's standard treatment most commonly includes radiotherapy, often combined with chemotherapy or surgery. There are so far no established biomarkers to predict response to radiation, and thus the aim of this study was to investigate a series of markers that could potentially identify HNSCC patients who would benefit from radiotherapy. The selected markers, both proteins (epidermal growth factor receptor, survivin and p53), and single nucleotide polymorphisms (SNPs) in the genes of XRCC3, XRCC1, XPC, XPD, MDM2, p53 and FGFR4 were correlated to the response to radiotherapy and overall survival. Investigations were performed on pretreatment tumor biopsies from patients classified as responders or nonresponders to radiotherapy. Protein expression was examined using immunohistochemistry and the genotyping of specific SNPs was analyzed using PCR-RFLP or pyrosequencing. We found that survivin expression was significantly stronger in the responder group (p = 0.003) and that patients with a strong survivin expression had a significantly better overall survival (p < 0.001). Moreover, downregulation of survivin by siRNA in two HNSCC cell lines significantly decreased their sensitivity to radiation. Among the SNPs analyzed, patients with the XPD Lys751Gln SNP had a significantly shorter overall survival (p = 0.048), and patients with the FGFR4 Gly388Arg SNP had a significantly longer overall survival (p = 0.010). In conclusion, our results suggest that survivin plays an important role in the response to radiotherapy and may be a useful marker for predicting radiotherapy response in patients with HNSCC.

Clinicopathological and prognostic significance of survivin over-expression in patients with esophageal squamous cell carcinoma: a meta-analysis

Background

The prognostic significance of survivin for survival of patients with esophageal squamous cell carcinoma (ESCC) remains controversial. Thus, meta-analysis of the literatures was performed in order to demonstrate its expression impact on ESCC clinicopathological features and prognosis.

Methodology

Relevant literatures were searched using PubMed, EMBASE and Medline Databases. Revman5.0 software was used to pool eligible studies and summary hazard ratio (HR). Correlation between survivin expression and clinicopathological features of ESCC was analyzed.

Principal Findings

Final analysis of 523 patients from 7 eligible studies was performed. Combined HR of survivin location in nuclei suggested that survivin expression has an unfavorable impact on ESCC patients' survival (n = 277 in 3 studies; HR = 1.89, 95% CI: 1.45–2.96; Z = 4.69; P<0.0001). Nevertheless, combined HR of survivin location in cytoplasm displayed that survivin expression has no significance for prognosis of ESCC patients (n = 113 in 2 studies; HR = 0.96, 95% CI: 0.96–5.69; Z = 0.04; P = 0.97); Combined odds ratio (OR) of survivin location in cytoplasm indicated that survivin expression is associated with ESCC advanced stage (n = 113 in 2 studies; OR = 0.36, 95% CI: 0.14–0.93; Z = 2.10; P = 0.04). Whereas, combined OR of survivin location in nuclei exhibited that survivin over-expression has no correlation with cell differentiation grade, lymph node status, depth of invasion, stage, and metastasis of ESCC.

Conclusions

This study showed that survivin expression detected by immunohistochemistry seems to be associated with a worse prognosis of ESCC patients. Survivin subcellular location may be an important factor impacting on ESCC development. Larger prospective studies should be performed to evaluate the status of survivin in predicting prognosis of patients with ESCC.

Progress in understanding the role of inhibitor of apoptosis proteins in molecular targeted therapy of esophageal cancer

The apoptosis and antiapoptotic signaling pathways play a critical role in the embryonic and lymphocyte development, immune system modulation, and tissue homeostasis, as well as carcinogenesis. As inhibitor of apoptosis proteins (IAPs) are highly expressed in several neoplasms and are closely related to carcinogenesis, cancer progression, radiochemotherapeutic resistance, and prognosis, therapies targeting IAPs have become a research hotspot for molecular targeted therapy of tumors. In recent years, many agents targeting IAPs which are being evaluated in clinical trials are showing promising prospect for neoplastic therapy. As such, the identification of key roles of IAPs in esophageal cancer has revealed their potential value as therapeutic targets. This report reviews the progress in understanding the role of IAPs in molecular targeted therapy of esophageal cancer.

High survivin expression as a risk factor in patients with anal carcinoma treated with concurrent chemoradiotherapy

PURPOSE

To investigate the prognostic value of survivin expression in pretreatment specimens from patients with anal cancer treated with concurrent 5-FU and mitomycin C-based chemoradiation (CRT).

MATERIAL AND METHODS

Immunohistochemical staining for survivin was performed in pretreatment biopsies of 62 patients with anal carcinoma. Survivin expression was correlated with clinical and histopathological characteristics as well as local failure free- (LFFS), distant metastases free- (DMFS), cancer specific- (CSS), and overall survival (OS).

RESULTS

Survivin staining intensity was weak in 10%, intermediate in 48% and intense in 42% of the patients. No association between survivin expression and clinicopathologic factors (tumor stage, age and HIV status) could be shown. In univariate analysis, the level of survivin staining was significantly correlated with DMFS (low survivin vs. high survivin: 94% vs. 74%, p = 0.04). T-stage, N-stage and the tumor grading were significantly associated with OS and CSS and with DMFS and LFFS, respectively. In multivariate analysis, survivin was confirmed as independent prognostic parameter for DMFS (RR, 0.04; p = 0.02) and for OS (RR, 0.27; p = 0.04).

CONCLUSION

Our results demonstrated that the level of pretreatment survivin is correlated with the clinical outcome in patients with anal carcinoma treated with concurrent CRT. Further studies are warranted to elucidate the complex role of survivin for the oncologic treatment and to exploit the protein as a therapeutic target in combined modality treatment of anal cancer.

Significance of survivin expression: Prognostic value and survival in stage III non-small cell lung cancer

This study was designed to determine the levels of survivin expression and identify its clinical significance as a prognostic factor for stage III non-small cell lung cancer (NSCLC). A total of 210 cases of stage III NSCLC were collected and the expression levels of survivin and vascular endothelial growth factor A (VEGF-A) in tumor tissues were investigated using immunohistochemistry (IHC). The medical records of the patients were reviewed to determine the association with clinical course. Of the 210 NSCLC tissues, 112 (53.3%) cases demonstrated positive expression of survivin protein. Coexpression of survivin and VEGF-A was identified. The 5-year survival rate of patients with positive survivin expression was significantly lower compared with the survivin-negative cancer patients (P<0.05). The expression of survivin in NSCLC correlated with tumor size. Survivin and VEGF-A were independent prognostic factors of stage III NSCLC. Survivin protein is a valuable marker of prognosis in stage III NSCLC patients.