Expression of the antiapoptosis gene, survivin, predicts death from recurrent colorectal carcinoma

Prognostic significance of survivin in resected gallbladder cancer

BACKGROUND

Survivin, a novel inhibitor of apoptosis, plays a role in oncogenesis and has been correlated with poor prognosis. We investigated its expression in gallbladder tissues of control, cholelithiasis, and gallbladder cancer (GBC). Survivin expression was correlated with different clinicopathologic parameters including prognosis in patients with GBC.

MATERIALS AND METHODS

Gallbladder tissue samples were collected from GBC (n = 39), cholelithiasis (n = 30), and control (n = 25). Expression of survivin messenger RNA (mRNA) was evaluated by real time polymerase chain reaction. Protein quantification was done by enzyme-linked immunosorbent assay.

RESULTS

Significantly higher expression of survivin mRNA was observed in GBC (2.9-fold) and cholelithiasis (1.85-fold) as compared with control (P < 0.0001). In GBC, increased survivin expression (mRNA and protein) was significantly associated with higher tumor stage (stage III versus stage II) (P < 0.0001) and poor tumor differentiation (poor and moderate versus well) (P < 0.0001). No significant correlation was observed with any of the other clinicopathologic factors studied. Increased expression of survivin was associated with shorter survival (median survival 11.5 mo versus 18 mo).

CONCLUSIONS

Differential expression of survivin in GBC suggests its possible role in gallbladder carcinogenesis. Its overexpression is associated with poor prognosis. Assessment of survivin might be used to stratify GBC patients for optimal treatment modalities, including targeted therapy.

Prognostic significance of survivin in breast cancer: meta-analysis

Survivin, an inhibitor of apoptosis protein, is a potentially prognostic factor and therapeutic target in breast carcinoma, but no consensus exists based on heterogeneous data. The aim of this present study is to clarify the prognostic relevance of survivin in breast cancer patients. Relevant articles were screened in PubMed and EMBASE databases. Patients' clinical characteristics, overall survival (OS), disease/recurrence-free survival (DFS/RFS) and positive expressed survivin rates were extracted for further analysis. Statistics extracted from Kaplan-Meier survival curves were calculated indirectly with methods developed by Parmar, Williamson, and Tierney. Multivariate Cox hazard regression analysis data were used directly in Stata 11.0. Pooled hazard ratio (HR) and 95% confidence interval (CI) were calculated to evaluate the prognostic role of survivin in breast cancer. Online literature search identified 23 articles containing 3,259 breast cancer patients. Our meta-analysis of all included studies about survival outcomes showed positive correlation between poor prognosis and survivin expression. Pooled HRs (95% CIs) for OS and DFS/RFS were 1.37 (1.12-1.68) and 1.34 (1.02-1.76), respectively. Subgroup analyses considering methods used to detect survivin (immunohistochemistry or not) and localization of survivin (whole, nuclear or cytoplasm of the cell) were also conducted, and all the above analyses supported the stability of the prognostic role of survivin. In addition, our study revealed a significant association between survivin expression and lymph node metastasis (OR: 2.74; 95% CI: 1.27-5.93) or stage of breast cancer (OR: 2.01; 95% CI: 1.29-3.13). Positive expression of survivin demonstrated a significantly higher risk of recurrence and decreased OS rates in breast cancer.

Evaluation of antagonistic effects of metformin with Cisplatin in gastric cancer cells

Metformin has recently been introduced as an anti-cancer agent. In this study, we evaluated the effect of metformin and metformin/cisplatin on human gastric MKN-45 cell line. When we used metformin alone, it could inhibit proliferation and induce apoptosis, but it diminish anti-proliferative effects of cisplatin when they are used in combination. Further, we checked mRNA levels of survivin, mTOR, and Akt by real-time PCR. When MKN-45 cells were treated with metformin/cisplatin, the expression of survivin and mTOR were increased. The antagonistic effect of metformin on cisplatin could be through survivin and mTOR signaling pathways. Our results also suggest that interfering effect of metformin on cisplatin may be also through upregulation of Akt. Regarding the pivotal role of Akt in drug resistance, it may be reasonable to conclude that the antagonistic effect of metformin on cisplatin effect may be through this central mediator of drug resistance. Taken together, it seems that metformin is not a good option for sensitizing MKN-45 cell line to cisplatin, and in co-prescription of metformin and cisplatin in gastric cancer patients who suffer diabetes type 2, it should be highly cared.

Expression of survivin mRNA in gallbladder cancer: a diagnostic and prognostic marker?

Survivin, an inhibitor of apoptosis, has been shown to be expressed in various malignancies. However, its role in gallbladder cancer (GBC) has not been evaluated yet. We investigated its expression in peripheral blood of patients with gallbladder diseases (gallstone disease (GSD), n = 30; GBC, n = 39) and compared with healthy controls (n = 25). Survivin expression was correlated with clinicopathological parameters, diagnosis, and prognosis of patients with GBC. Expression of survivin messenger RNA (mRNA) in blood was evaluated by real-time PCR. Significantly higher (P < 0.0001) expression of survivin mRNA was observed in GBC (2.2-fold) and GSD (1.52-fold) as compared to control. In GBC, increased survivin expression was significantly associated with higher tumor stage (stage III vs. stage II; P < 0.0001) and tumor differentiation (poor and moderate vs. well differentiated; P < 0.0001). No significant correlation was observed with any of the other clinicopathological parameters (age, gender, and presence or absence of gallstones) studied. Cutoff value of survivin mRNA relative quantification (RQ) was 1.08, with a sensitivity of 98.55 % and specificity of 100 % for the diseased group (GSD or GBC). RQ value of 1.71 differentiated GBC from GSD with a sensitivity of 89.74 % and specificity of 100 %. Increased expression of survivin was associated with a shorter median overall survival (12 vs. 18 months) in GBC patients. Differential expression of survivin in GBC suggests its possible role and association with poor prognosis. Expression of survivin in peripheral blood could be useful both in the diagnosis and prognosis of GBC.

YM155 reverses rapamycin resistance in renal cancer by decreasing survivin

PURPOSE

Mammalian target of rapamycin inhibitor has exhibited promising anticancer activity for the treatment of renal cell carcinoma (RCC). However, many patients acquire resistance to therapeutic agents leading to treatment failure. The objective of this study was to determine whether treatment with YM155, a novel small molecule inhibitor of survivin, could reverse rapamycin resistance in a rapamycin-resistant RCC.

METHODS

We induced a rapamycin-resistant clear cell carcinoma cell line (Caki-1-RapR). We showed that survivin gene expression was significantly up-regulated in Caki-1-RapR compared with that in its parent cells (Caki-1). Therefore, we hypothesized that targeting of survivin in Caki-1-RapR could reverse the resistant phenotype in tumor cells, thereby enhancing the therapeutic efficacy of rapamycin. We used both in vitro and in vivo models to test the efficacy of YM155 either as a single agent or in combination with rapamycin.

RESULTS

In Caki-1-RapR cells, YM155 significantly decreased survivin gene and protein expression levels and cell proliferation in a dose-dependent manner in vitro. In addition, YM155 treatment significantly reversed rapamycin resistance in cancer cells. In a nude mouse tumor xenograft model, YM155 significantly inhibited the growth of Caki-1-RapR tumor. In addition, YM155 significantly enhanced the antitumor effects of rapamycin in Caki-1-RapR tumor.

CONCLUSIONS

Our results suggest a potentially novel strategy to use YM155 to overcome the resistance in tumor cells, thereby enhancing the effectiveness of molecular target therapy in RCC.

Proteome analysis of a hepatocyte-specific BIRC5 (survivin)-knockout mouse model during liver regeneration

The Baculoviral IAP repeat-containing protein 5 (BIRC5), also known as inhibitor of apoptosis protein survivin, is a member of the chromosomal passenger complex and a key player in mitosis. To investigate the function of BIRC5 in liver regeneration, we analyzed a hepatocyte-specific BIRC5-knockout mouse model using a quantitative label-free proteomics approach. Here, we present the analyses of the proteome changes in hepatocyte-specific BIRC5-knockout mice compared to wildtype mice, as well as proteome changes during liver regeneration induced by partial hepatectomy in wildtype mice and mice lacking hepatic BIRC5, respectively. The BIRC5-knockout mice showed an extensive overexpression of proteins related to cellular maintenance, organization and protein synthesis. Key regulators of cell growth, transcription and translation MTOR and STAT1/STAT2 were found to be overexpressed. During liver regeneration proteome changes representing a response to the mitotic stimulus were detected in wildtype mice. Mainly proteins corresponding to proliferation, cell cycle and cytokinesis were up-regulated. The hepatocyte-specific BIRC5-knockout mice showed impaired liver regeneration, which had severe consequences on the proteome level. However, several proteins with function in mitosis were found to be up-regulated upon the proliferative stimulus. Our results show that the E3 ubiquitin-protein ligase UHRF1 is strongly up-regulated during liver regeneration independently of BIRC5.

Clinical prognostic value of combined analysis of Aldh1, Survivin, and EpCAM expression in colorectal cancer

BACKGROUND

Tumour aggressiveness might be related to the degree of main cancer hallmark acquirement of tumour cells, reflected by expression levels of specific biomarkers. We investigated the expression of Aldh1, Survivin, and EpCAM, together reflecting main cancer hallmarks, in relation to clinical outcome of colorectal cancer (CRC) patients.

METHODS

Immunohistochemistry was performed using a tumour tissue microarray of TNM (Tumour, Node, Metastasis)-stage I-IV CRC tissues. Single-marker expression or their combination was assessed for associations with the clinical outcome of CRC patients (N=309).

RESULTS

Increased expression of Aldh1 or Survivin, or decreased expression of EpCAM was each associated with poor clinical outcome, and was therefore identified as clinically unfavourable expression. Analyses of the combination of all three markers showed worse clinical outcome, specifically in colon cancer patients, with an increasing number of markers showing unfavourable expression. Hazard ratios ranged up to 8.3 for overall survival (P<0.001), 36.6 for disease-specific survival (P<0.001), and 27.1 for distant recurrence-free survival (P<0.001).

CONCLUSIONS

Our data identified combined expression levels of Aldh1, Survivin, and EpCAM as strong independent prognostic factors, with high hazard ratios, for survival and tumour recurrence in colon cancer patients, and therefore reflect tumour aggressiveness.

Identification of novel helper epitope peptides of Survivin cancer-associated antigen applicable to developing helper/killer-hybrid epitope long peptide cancer vaccine

We identified novel helper epitope peptides of Survivin cancer antigen, which are presented to both HLA-DRB1*01:01 and DQB1*06:01. The helper epitope also contained three distinct Survivin-killer epitopes presented to HLA-A*02:01 and A*24:02. This 19 amino-acids epitope peptide (SU18) induced weak responses of Survivin-specific CD4(+) and CD8(+) T cells though it contained both helper and killer epitopes. To enhance the vaccine efficacy, we synthesized a long peptide by conjugating SU18 peptide and another DR53-restricted helper epitope peptide (SU22; 12 amino-acids) using glycine-linker. We designated this artificial 40 amino-acids long peptide containing two helper and three killer epitopes as Survivin-helper/killer-hybrid epitope long peptide (Survivin-H/K-HELP). Survivin-H/K-HELP allowed superior activation of IFN-γ-producing CD4(+) Th1 cells and CD8(+) Tc1 cells compared with the mixture of its component peptides (SU18 and SU22) in the presence of OK-432-treated monocyte-derived DC (Mo-DC). Survivin-H/K-HELP-pulsed Mo-DC pretreated with OK-432 also exhibited sustained antigen-presentation capability of stimulating Survivin-specific Th1 cells compared with Mo-DC pulsed with a mixture of SU18 and SU22 short peptides. Moreover, we demonstrated that Survivin-H/K-HELP induced a complete response in a breast cancer patient with the induction of cellular and humoral immune responses. Thus, we believe that an artificially synthesized Survivin-H/K-HELP will become an innovative cancer vaccine.

Significance of intracellular localization of survivin in cervical squamous cell lesions: Correlation with disease progression

Survivin is a member of the inhibitor of apoptosis protein family. Under normal circumstances, survivin is expressed in embryonic and fetal tissues, but is completely downregulated in normal adult tissues. Notably, this protein has been found to be prominently expressed in a variety of human malignant tumors. The present study was designed to evaluate the possible role of survivin in the tumorigenesis of cervical intraepithelial neoplasia and invasive squamous cell carcinoma (SCC) of the uterine cervix. In addition, it was investigated whether the nuclear or cytoplasmic expression of survivin is associated with tumor progression. In total, 71 samples of cervical squamous tissue were obtained, including 15 normal squamous epithelia, 25 high-grade squamous intraepithelial lesions (HSILs) and 31 SCCs, from cone biopsy and hysterectomy specimens and stained for survivin expression by immunohistochemistry. The intensity of survivin expression tended to increase with tumor progression (60.0% of normal mucosa, 76.0% of HSIL and 80.6% of SCC samples demonstrated high intensity survivin expression), but this correlation was not found to be statistically significant. However, a statistically significant difference was identified in the intracellular localization of survivin among the normal mucosa, HSIL and SCC samples (P<0.001). In total, 72% (18/25) of HSIL and 54.8% (17/31) of SCC cases expressed cytoplasmic staining in contrast to the nuclear staining of the normal mucosa. In addition, 64% (16/25) of HSIL and 42% (13/31) of SCC cases showed coexpression in the nucleus and cytoplasm. An inverse correlation was identified between the decrement of nuclear survivin expression and tumor progression, but was not statistically significant (P=0.08). These results indicated that analysis of the intracellular expression of survivin (particularly cytoplasmic expression) is a marker for predicting disease progression in the uterine cervix.

The role of survivin in thyroid tumors: differences of expression in well-differentiated, non-well-differentiated, and anaplastic thyroid cancers

BACKGROUND

Survivin is involved in human cancer and is responsible for aggressive biological behavior and poor clinical outcomes in several human malignancies. Thus, we hypothesized that the upregulation of survivin protein expression may be enhanced in parallel with transition toward a poorly differentiated phenotype in human thyroid carcinomas.

METHODS

The expression of survivin was evaluated, using a standard linked streptavidin-biotin horseradish peroxidase technique technique, in a series of 56 human thyroid carcinomas (42 papillary, 4 poorly differentiated, and 10 anaplastic carcinomas) and thyroid carcinoma cell lines at different degrees of differentiation.

RESULTS

The cytoplasmic expression of survivin protein was significantly upregulated in all thyroid tumors. A statistically significant association was found between nuclear survivin expression and anaplastic thyroid cancer (mean ± SD: well-differentiated thyroid cancer, 1.22 ± 20.21; non-well-differentiated thyroid cancer, 34.00 ± 25.17; anaplastic thyroid cancer, 56.50 ± 22.10; p<0.001). Nuclear staining of survivin has been shown in poorly differentiated and anaplastic thyroid carcinomas, and this is likely due to the upregulation of the ΔEx3 survivin splicing variant, as shown in poorly differentiated/anaplastic thyroid carcinoma cell lines. Of note, selected thyroid tumors characterized by a mixed population of differentiated and undifferentiated neoplastic cells, likely progressing from well to poorly differentiated and anaplastic phenotypes, exhibited cytoplasmic expression of survivin in differentiated fields and nuclear protein staining in poorly differentiated and anaplastic areas. This expression profile provides substantial added value to conventional clinical markers in predicting anaplastic cancer. The cut-off for distinguishing thyroids that developed ATC from those that remained differentiated was >30% of nuclear survivin expression. The receiver operating characteristic (ROC) area was 0.92, with a p-value of <0.0001.

CONCLUSIONS

Upregulation of survivin expression may be a molecular marker of dedifferentiation in thyroid epithelial carcinomas, likely being responsible for survival responses of tumor cells and, thus, favoring progression toward a poorly differentiated phenotype.

Influence of survivin-targeted siRNA on the biological features of colorectal carcinoma cells

The transient transfection of survivin-targeted siRNA to Lovo cells and its influence on the biological features were studied. Two pairs of 19 base pairs (bp) siRNA-specific targeted survivin gene were designed and synthesized by in vitro transcription (Survivin-1, Survivin-2). After transient transfection of the two survivin-targeted siRNAs to Lovo cells by Lipofectamine™ 2000, the expression of survivin mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR). Apoptosis was detected by flow cytometry and cell proliferation was evaluated by MTT assay. We found that the expression levels of survivin mRNA of the two RNAi groups (Survivin-1 group and Survivin-2 group) respectively decreased by 70% and 39.1% compared with the control Lovo's. Seventy-two hours after transfection, apoptosis rates of the two RNAi groups were 21.51% and 26.28%, both of which were higher than control Lovo's (9.03%). The results at 72 h after transfection were that the optical density (OD) at 490 nm of the two RNAi groups was 0.581 ± 0.070 and 0.681 ± 0.104, both of which were much lower than the control Lovo's (2.060 ± 0.272). Based on the results, we can draw a conclusion that the two survivin-targeted siRNAs successfully suppressed the expression of survivin mRNA, inhibited cell growth and induce cell apoptosis. It provides a powerful evidence for colorectal carcinoma gene therapy.

Inhibitor of apoptosis proteins as targets for anticancer therapy

Cell death by apoptosis plays a critical role in regulating the subtle balance between cell death and proliferation to maintain tissue homeostasis. Accordingly, tipping the balance in either direction may cause human disease. Too little cell death may promote tumor formation and progression. In addition, killing of cancer cells by current therapies is largely due to induction of apoptosis in tumor cells. Since a hallmark of human cancers is their resistance to apoptosis, there is a demand to develop novel strategies that restore the apoptotic machinery in order to overcome cancer resistance. Inhibitor of apoptosis proteins (IAPs) block apoptosis at the core of the apoptotic machinery by inhibiting caspases. Elevated levels of IAPs are found in many human cancers and have been associated with poor prognosis. Recent insights into the role of IAPs have provided the basis for various exciting developments that aim to modulate the expression or function of IAPs in human cancers. Targeting IAPs (e.g., by antisense approaches or small-molecule inhibitors) presents a promising novel approach to either directly trigger apoptosis or to potentiate the efficacy of cytotoxic therapies in cancer cells. Thus, inhibition of IAPs such as X chromosome-linked IAP may prove to be a successful strategy to overcome apoptosis resistance of human cancers that deserves further exploitation.

Survivin - biology and potential as a therapeutic target in oncology

Survivin is a member of the inhibitor-of-apoptosis proteins (IAPs) family; its overexpression has been widely demonstrated to occur in various types of cancer. Overexpression of survivin also correlates with tumor progression and induces anticancer drug resistance. Interestingly, recent studies reveal that survivin exhibits multiple pro-mitotic and anti-apoptotic functions; the differential functions of survivin seem to be caused by differential subcellular localization, phosphorylation, and acetylation of this molecule. In this review, the complex expression regulations and post-translational modifications of survivin are discussed. This review also discusses how recent discoveries improve our understanding of survivin biology and also create opportunities for developing differential-functioned survivin-targeted therapy. Databases such as PubMed, Scopus® (Elsevier, New York, NY, USA), and SciFinder® (CAS, Columbus, OH, USA) were used to search for literature in the preparation of this review.

Exploring the role of post-translational modifications on protein-protein interactions with survivin

Survivin is a member of the inhibitor of apoptosis protein (IAP) family with crucial roles in apoptosis and cell cycle regulation. Post-translational modifications (PTMs) have a ubiquitous role in the regulation of a diverse range of proteins' cellular functions and survivin is not an exception. Phosphorylation, acetylation and ubiquitination seem to regulate survivin anti-apoptotic and mitotic roles and also its nuclear localization. In the present review we explore the role of PTMs on protein-protein interactions focused on survivin to provide new insights into the functions and cell localization of this IAP in pathophysiological conditions, which might help the envisioning of novel targeted therapies for diseases characterized by impaired survivin activity. Protein-protein interaction analysis was performed with bioinformatics tools based on published data aiming to give an integrated perspective of this IAP's role in the cell.

The prognostic value of survivin expression in patients with colorectal carcinoma: a meta-analysis

OBJECTIVE

The prognostic role of survivin in colorectal carcinoma remains controversial. This meta-analysis aimed to explore the association between survivin expression and survival outcomes in patients with colorectal carcinoma.

METHODS

A comprehensive literature search for relevant studies published up to April 2013 was performed using PubMed, MEDLINE and ISI Web of Science. Only articles in which survivin was detected by immunohistochemical staining were included. This meta-analysis was done using STATA and Review Manager.

RESULTS

A total of 1784 patients from 14 studies were included in the analysis. Our results showed that survivin overexpression in patients with colorectal carcinoma was significantly associated with poor overall survival (hazard ratio, 1.505; 95% confidence interval, 1.197-1.893; P = 0.000) and disease-free survival (hazard ratio, 2.323; 95% confidence interval, 1.687-3.199; P = 0.000). The results indicated that a significant relationship between survivin expression and overall survival was also exhibited in studies with an Asian country (hazard ratio, 1.684; 95% confidence interval, 1.477-1.921), patient number >100 (hazard ratio, 1.604; 95% confidence interval, 1.371-1.877), the cut-off level <50% (hazard ratio, 1.449; 95% confidence interval, 1.045-2.010), the percentage of survivin overexpression >50% (hazard ratio, 1.528; 95% confidence interval, 1.056-2.211) and the hazard ratio estimated (hazard ratio, 1.643; 95% confidence interval, 1.262-2.139). Moreover, upregulation of survivin was associated with stages (III/IV vs. I/II: odds ratio, 1.08; 95% confidence interval, 0.80-1.46), the depth of invasion (T3/T4 vs. T1/T2: odds ratio, 1.79; 95% confidence interval 0.67-4.74), lymph node metastasis (positive vs. negative: odds ratio, 1.49; 95% confidence interval, 0.99-2.26), distant metastasis (positive vs. negative: odds ratio, 2.37; 95% confidence interval, 0.99-5.72) and grade of differentiation (well/moderate vs. poor: odds ratio, 1.02; 95% confidence interval, 0.43-2.41), but without significance.

CONCLUSION

The present meta-analysis indicated that upregulation of survivin was associated with poor prognosis in patients with colorectal carcinoma.

ARC is highly expressed in nasopharyngeal carcinoma and confers X-radiation and cisplatin resistance

Apoptosis repressor with caspase recruitment domain (ARC), an inhibitor of apoptosis, is primarily expressed in terminally differentiated tissues. Recent studies have revealed that ARC is highly expressed in a variety of human cancer cell lines and epithelial-derived cancers, which suggests that ARC plays an important role in the process of carcinogenesis. However, whether ARC is involved in the development of nasopharyngeal carcinoma (NPC) and the various roles it plays in NPC remain unclear. In the present study, we examined the expression of ARC in NPC cell lines and NPC tissues and the relationship between its subcellular expression and clinicopathological grade; moreover, we explored the effect of this protein on radiation resistance and chemoresistance in NPC cells. We found that cytoplasmic ARC was expressed at high levels in NPC tissues, at moderate levels in severe atypical hyperplasia and at low levels in benign nasopharyngeal tissues. High expression of cytoplasmic and nuclear ARC was correlated with advanced local invasion. However, only a small amount of nuclear ARC was expressed in NPC in contrast to cytoplasmic ARC. We also found that attenuation of ARC expression by miRNA resulted in decreased X-radiation and cisplatin resistance in NPC CNE-2 cells. In contrast, overexpression of ARC resulted in increased X-radiation and cisplatin resistance in NPC 6-10B cells. Furthermore, we demonstrated that ARC appears to be critical for blocking the activation of casapse-8 and casapse-2 in NPC cells subjected to X-radiation or cisplatin. These results suggest that high expression of ARC plays an important role in the pathogenesis of NPC and leads to X-radiation and cisplatin resistance in NPC.

Prognostic and clinicopathological significance of survivin in colorectal cancer: a meta-analysis

Survivin/BIRC5 is a potentially interesting prognostic marker and therapeutic target in colorectal cancer (CRC). However, the available data on survivin expression in CRC are heterogeneous. Thus, to clarify the prognostic relevance of survivin in patients with CRC and its association with clinicopathological parameters we performed a meta-analysis. We screened PubMed and EMBASE for those studies that investigated the prognostic value of survivin and its association with clinicopathological parameters in CRC. Data from eligible studies were extracted and included into the meta-analyses using a random effects model. Electronical literature search identified 15 studies including 1934 patients with CRC mostly detecting survivin by immunohistochemistry (IHC). Pooled hazard ratios of 11 studies that performed survival analysis revealed a positive correlation between survivin expression and poor prognosis (HR 1.93; 95% CI: 1.55–2.42; P<0.00001; I² = 23%). Subgroup analyses with respect to the detection method, HR estimation, global quality score and the country of origin in which the study was conducted supported the stability of this observation. In addition, meta-analyses revealed a significant association between expression of survivin and the presence of lymph node metastases (OR: 0.37; 95% CI: 0.19–0.75; I² = 61%) or blood vessel invasion (OR: 0.50; 95% CI: 0.28–0.90; I² = 0%). Expression of survivin indicates poor prognosis and a pro-metastatic phenotype and may be useful in identifying a subgroup of patients that could benefit from a targeted therapy against survivin in CRC.

Cotransfection of survivin and CD44v3 short hairpin RNAs affects proliferation, apoptosis, and invasiveness of colorectal cancer

INTRODUCTION

Colorectal cancer is one of the common malignant tumors in humans, and the incidence rate is gradually increasing year by year. Survivin and CD44v3 are ideal targets for gene therapy due to their overexpression in colorectal cells. Studies show that downregulation of survivin could promote apoptosis and depress proliferation, and reduction of CD44v3 expression could inhibit tumor invasive capacity. It is difficult to achieve satisfactory curative effect.

OBJECTIVE

In this study, we use survivin and CD44v3 short hairpin RNAs (shRNA) combined transfection into colorectal cancer cell line SW480 to investigate its effects on the cell apoptosis, proliferation and invasiveness.

METHODS

ShRNA plasmids targeting survivin and CD44v3 were singly or co-transfected into SW480 cells.

RESULTS

The co-transfection group exhibited the most significant inhibitory effect on cell growth (P < 0.05) and the highest apoptosis rate (P < 0.05). In addition, the invasive capacity in the co-transfected group was the least. The tumor inhibition rate of the cotransfected group in xenograft tumor mice was significantly higher than other groups (P < 0.05). Moreover, the microvessel density of the co-transfected group was significantly decreased compared with other groups (P < 0.05).

CONCLUSION

These results suggest combined transfection of survivin shRNA and CD44v3 shRNA may produce a synergistic effect on gene therapy in colorectal cancer.

Decrease of survivin, p53 and Bcl-2 expression in chemorefractory colorectal liver metastases may be predictive of radiosensivity radiosensivity after radioembolization with yttrium-90 resin microspheres

In a prospective multicenter phase II trial of radioembolization with yttrium-90 (⁹⁰Y-RE) in chemorefractory liver-dominant metastatic colorectal cancer (mCRC), we showed that median survival was 12.6 months (95% CI 7.0–18.3) with 48% of 50 patients achieving disease control. In this extension retrospective study, we analyzed whether a panel of biomarkers, known to be associated to an adverse clinical outcome, underwent variations in CRC liver metastases pre and post ⁹⁰Y-RE.

Of the 50 patients included in the study, 29 pre-⁹⁰Y-RE therapy and 15 post-⁹⁰Y-RE had liver biopsy specimens available. In these series we investigated survivin, p53, Bcl-2 and Ki-67 expression pre- and post-⁹⁰Y-RE by immuhistochemistry (IHC). Our findings evidenced a decrease of survivin (77% vs 33%), p53 (93% vs 73%), Bcl-2 (37% vs 26%) expression as well as of Ki-67 proliferation index (62.5% vs 40%) on liver biopsies collected post-⁹⁰Y-RE as compared to pre-⁹⁰Y-RE. In the subset of 13 matched liver metastases we further confirmed the reduction of survivin (92.3% vs 53.8%; p = 0.06), p53 (100% vs 69.2%; p = 0.05) and Bcl-2 (69.2% vs 53.8%; p = 0.05) expression post-⁹⁰Y-RE. This biomarker modulation was accompanied by morphological changes as steatohepatitis, hepatocyte necrosis, collagen deposition, proliferating and/or bile duct ectasia, focal sinusoidal dilatation and fibrosis.

Although our analysis was conducted in a very limited number cases, these changes appear strictly related to the response to ⁹⁰Y-RE therapy and may deserve further investigation on a larger series of patients.

Survivin -31G>C polymorphism and gastrointestinal tract cancer risk: a meta-analysis

Background

Emerging evidence showed that common functional −31G>C polymorphism (rs9904341 G>C) in the promoter region of the survivin gene is involved in the regulation of survivin expression, thus increasing an individual’s susceptibility to gastrointestinal tract (GIT) cancer; but individually published results are inconclusive. The aim of this systematic review and meta-analysis was to derive a more precise estimation of the association between survivin −31G>C polymorphism and GIT cancer risk.

Methods

A literature search of PubMed, Embase, Web of Science and CBM databases was conducted from inception through July 1st, 2012. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association.

Results

Nine case-control studies were included with a total of 2,231 GIT cancer cases and 2,287 healthy controls. The results indicated that survivin −31G>C polymorphism was associated with increased risk of GIT cancer. In the stratified analysis by cancer types, significant associations were observed between survivin −31G>C polymorphism and increased risk of colorectal and gastric cancers. However, the lack of association of survivin −31G>C polymorphism with esophageal cancer risk may be due to a lack of a sufficient number of eligible studies and the influence of different genetic and environmental factors.

Conclusion

Results from the current meta-analysis suggests that survivin −31G>C polymorphism might increase the risk of GIT cancer, especially among gastric and colorectal cancers.

The detergent-soluble cytoplasmic pool of survivin suppresses anoikis and its expression is associated with metastatic disease of human colon cancer

Survivin is a component of the chromosomal passenger complex (CPC) that is essential for accurate chromosome segregation. Interfering with the function of Survivin in mitosis leads to chromosome segregation errors and defective cytokinesis. Survivin contains a Baculovirus IAP Repeat (BIR) and therefore was originally classified as inhibitor of apopotosis protein (IAP), yet its role in apoptosis after cellular stress remains largely unknown. We demonstrate here, that Survivin predominantly suppresses anoikis, a form of programmed cell death induced by loss of cellular adhesion to extracellular matrix. Interestingly, cells ectopically overexpressing EGFP-Survivin showed after loss of cell-matrix-interaction a decreased expression of IκB-α. Subsequent subcellular protein fractionation and immunoprecipitation experiments revealed that XIAP interacts with detergent-soluble Survivin which is known to cooperatively activate NF-κB signaling. Examination of the expression levels of detergent soluble Survivin in colorectal cancer cell lines and in colorectal cancerous tissues revealed that detergent soluble cytoplasmic Survivin levels correlated inversely with anoikis susceptibility in colorectal cancer. Therefore, the detergent soluble cytoplasmic Survivin might be a promising predictive biomarker for lymph node and distant metastases of colorectal cancer. We conclude that an anti-apoptotic function of detergent-soluble Survivin in interphase cells experiencing anoikis is mediated at least via XIAP/IκB-α/NF-κB signaling.

Performance of survivin mRNA as a biomarker for bladder cancer in the prospective study UroScreen

Background

Urinary biomarkers have the potential to improve the early detection of bladder cancer. Most of the various known markers, however, have only been evaluated in studies with cross-sectional design. For proper validation a longitudinal design would be preferable. We used the prospective study UroScreen to evaluate survivin, a potential biomarker that has multiple functions in carcinogenesis.

Methods/Results

Survivin was analyzed in 5,716 urine samples from 1,540 chemical workers previously exposed to aromatic amines. The workers participated in a surveillance program with yearly examinations between 2003 and 2010. RNA was extracted from urinary cells and survivin was determined by Real-Time PCR. During the study, 19 bladder tumors were detected. Multivariate generalized estimation equation (GEE) models showed that β-actin, representing RNA yield and quality, had the strongest influence on survivin positivity. Inflammation, hematuria and smoking did not confound the results. Survivin had a sensitivity of 21.1% for all and 36.4% for high-grade tumors. Specificity was 97.5%, the positive predictive value (PPV) 9.5%, and the negative predictive value (NPV) 99.0%.

Conclusions

In this prospective and so far largest study on survivin, the marker showed a good NPV and specificity but a low PPV and sensitivity. This was partly due to the low number of cases, which limits the validity of the results. Compliance, urine quality, problems with the assay, and mRNA stability influenced the performance of survivin. However, most issues could be addressed with a more reliable assay in the future. One important finding is that survivin was not influenced by confounders like inflammation and exhibited a relatively low number of false-positives. Therefore, despite the low sensitivity, survivin may still be considered as a component of a multimarker panel.

Vaccines for colorectal cancer and renal cell carcinoma

Vaccines have shown promise for the prevention and treatment of solid tumors. Colorectal cancer and renal cell carcinoma are common malignancies that may be amenable to vaccine strategies. This review summarizes target antigens in colorectal and renal cell carcinoma, discusses some of the vaccine approaches in development, and details the results of pivotal phase III trials evaluating therapeutic vaccines in patients with advanced colorectal and renal cell carcinoma. Finally, some of the challenges with vaccine development for colorectal and renal cell carcinoma are described.

BIRC5 promoter SNPs do not affect nuclear survivin expression and survival of malignant pleural mesothelioma patients

PURPOSE

Malignant pleural mesothelioma is an incurable, asbestos-associated cancer. Its incidence is rapidly increasing and survival remains short. Apoptosis deregulation is an important feature of cancer and survivin, a member of the inhibitor-of-apoptosis-protein family encoded by the BIRC5 gene, has been suggested to have a role in the development and progression of several cancers. Genetic variability, in particular single nucleotide polymorphisms in the BIRC5 promoter, may affect the protein's expression levels. The aim of our study was to elucidate the effects of BIRC5 promoter single nucleotide polymorphisms on survivin expression, patient survival and age at diagnosis in malignant pleural mesothelioma.

METHODS

Archival mesothelioma samples from 101 Slovenian patients were immunohistochemically analysed for survivin expression. DNA was extracted from tumour samples and genotyped for three BIRC5 promoter single nucleotide polymorphisms (-31G > C, -241C > T and -625G > C). Genotypes were associated with nuclear survivin expression. Nuclear survivin expression, genotypes, haplotypes, histological type, gender and asbestos exposure were included in univariate Cox survival analyses.

RESULTS

Survivin expression was detected in both tumour cell nuclei and cytoplasms in all analysed samples. No association between BIRC5 promoter polymorphism genotypes or haplotypes and nuclear survivin expression was found. Polymorphism -241C > T affected patients' age at diagnosis. Survival analysis confirmed that younger age at diagnosis and epitheloid histological type improved survival, but no significant effects of nuclear survivin expression or genotype/haplotype on overall survival were observed.

CONCLUSION

Our findings indicate no relationship between BIRC5 genotypes and survivin expression or overall survival in mesothelioma patients. We observed that BIRC5 -241C > T polymorphism had a significant effect on patient age at diagnosis.

Survivin promoter -31G/C (rs9904341) polymorphism and cancer susceptibility: a meta-analysis

This study aimed to perform a meta-analysis to assess the association of survivin -31 G/C promoter polymorphism and cancer risk. Thirteen case-control studies identified through PubMed and published between 2007 and 2011 with a total of 3329 cancer cases and 3979 controls were included in this meta-analysis. Odds ratio (OR) and 95% confidence interval (95% CI) were used to investigate the strength of the association. Overall, the pooled analysis showed that survivin -31C allele was associated with 1.27 fold increased risk of cancer compared with the -31G allele (95% CI = 1.091-1.479; random model). Subgroup analyses based on type of cancer and ethnicity were also performed, and results indicated that survivin -31G/C polymorphism was not associated with risk of gastric cancer [OR = 2.879; 95% CI = 0.553-15.004) for CC vs.GG] and esophageal cancer [OR = 1.352; 95% CI = 0.494-3.699) for CC vs.GG]. Stratification on the basis of ethnicity showed that the risk due to -31C allele was significant only in Asian population [OR = 1.894; 95% CI = 1.206-2.974 for CC vs.GG]. The present meta-analysis suggests an important role of survivin -31 G/C polymorphism with cancer risk especially in Asian population. However, further studies with larger sample size are required to draw more comprehensive conclusions and provide more precise evidence in individual cancers.

[Inhibitory effects of the survivin siRNA transfection on human lung adenocarcinoma cells SPCA1 and SH77]

BACKGROUND AND OBJECTIVE

Survivin, a member of the inhibitor of apoptosis (IAP) protein family, has been demonstrated as a potential new target for apoptosis-based therapy in cancer and lymphoma. The aim of this study is to investigate effects and mechanisms of survivin siRNA transfection on lung adenocarcinoma cell lines SPCA1 and SH77.

METHODS

A siRNA plasmid expression vector and pSi scrambled against survivin were constructed and transfected into SPCA1 and SH77 cells with Lipofectamine 2000. The proliferations of lung adenocarcinoma SPCA1 and SH77 cells were detected by MTT. The apoptotic rate and cell cycle were detected by flow cytometer. The activity of survivin mRNA and protein expression were analyzed with RT-PCR and Western blot.

RESULTS

Survivin siRNA reduced the proliferation of SPCA1 and SH77 cells. Cell cycle was inhibited in G0/G1. Expressions of survivin siRNA mRNA and protein were reduced in transfected cells compared with the control cells.

CONCLUSIONS

siRNA targeted against survivin can effectively suppress SPCA1 and SH77 cells proliferation and significantly induce SPCA1 and SH77 cells apoptosis.

Impacting tumor cell-fate by targeting the inhibitor of apoptosis protein survivin

Survivin (BIRC5), a member of the inhibitor of apoptosis protein (IAP) family that inhibits caspases and blocks cell death is highly expressed in cancer and is associated with a poorer clinical outcome. Functioning simultaneously during cell division and apoptosis inhibition, survivin plays a pivotal role in determining cell survival. Survivin has consistently been identified by molecular profiling analysis to be associated with higher tumor grade, more advanced disease, abbreviated survival, accelerated rates of recurrence, and chemotherapy and radiation resistance. Survivin's differential expression in cancer compared to normal tissue and its role as a nodal protein in a number of cellular pathways make it a highly flexible therapeutic target, suitable for small-molecule inhibitiors, molecular antagonists, and vaccination-based therapies. By targeting survivin it is hoped that multiple tumor signaling circuitries may be simultaneously disabled. This effect may be applicable to many tumor histologies irrespective of specific genetic makeup. To date, survivin inhibitors have shown modest activity as single agents, but it is anticipated that when given in combination with cytotoxic chemotherapy or monoclonal antibodies they may exhibit enhanced efficacy. This review discusses the complex circuitry of survivin in human cancers and highlights clinical trials involving novel agents that target this important protein.

Survivin isoforms and clinicopathological characteristics in colorectal adenocarcinomas using real-time qPCR

AIM: To investigate three isoforms of survivin in colorectal adenocarcinomas.

METHODS: We used the LightCycler Technology (Roche), along with a common forward primer and reverse primers specific for the splice variants and two common hybridization probes labeled with fluorescein and LightCycler-Red fluorophore (LC-Red 640). Real time quantitative polymerase chain reaction (PCR) was performed on cDNAs from 52 tumor specimens from colorectal cancer patients and 10 unrelated normal colorectal tissues. In the patients group, carcinoembryonic antigen (CEA) and CA19-9 tumor markers were also measured immunochemically.

RESULTS: Wild type survivin mRNA isoform was expressed in 48% of the 52 tumor samples, survivin-2b in 38% and survivin-ΔΕx3 in 29%, while no expression was found in normal tissues. The mRNA expression of wild type survivin presented a significant correlation with the expression of the ratio of survivin-2b, survivin-ΔΕx3, survivin-2b/wild type survivin and survivin-ΔΕx3/wild type survivin (P < 0.001). The mRNA expression of wild-survivin and survivin-ΔΕx3 was related with tumor size and invasion (P = 0.006 and P < 0.005, respectively). A significant difference was found between survivin-2b and morphologic cancer type. Also, the ratio of survivin-ΔEx3/wild-survivin was significantly associated with prognosis. No association was observed between the three isoforms and grade, metastasis, Dukes stage and gender. The three isoforms were not correlated with CEA and CA19-9.

CONCLUSION: Survivin isoforms may play a role in cell apoptosis and their quantification could provide information about clinical management of patients suffering from colorectal cancer.

Combined transfection of shRNAs targeting survivin and CD44v3 inhibits proliferation and reduces invasion in human colorectal carcinoma cell line SW480

AIM: To investigate the effect of combined transfection of short hairpin RNAs (shRNAs) targeting survivin and CD44v3 on cell proliferation and invasion in human colorectal carcinoma cell line SW480 and to provide experiment evidence for gene therapy of colorectal carcinoma.

METHODS: Plasmids carrying shRNAs targeting survivin and CD44v3 were designed, constructed and transfected into SW480 cells. SW480 cells were divided into negative control group, blank control group, survivin shRNA group, CD44v3 shRNA group and co-transfection group. Survivin and CD44v3 protein expression was analyzed by Western blot. Cell apoptosis, proliferation and invasion were measured by flow cytometry, MTT assay and Transwell chamber assay, respectively.

RESULTS: The expression of survivin and CD44v3 proteins in the co-transfection group was reduced by 84.2% ± 0.3% and 77.3% ± 0.1%, respectively. Co-transfection inhibited protein expression more efficiently than single-plasmid transfection (P < 0.05). After transfection for 120 h, the reduced rate of cell growth was 44.3% ± 0.1% in the co-transfection group, 21.5% ± 0.2% in the survivin shRNA group, and 26.4% ± 0.2% in the CD44v3 shRNA group. Combined transfection inhibited cell proliferation more efficiently than single-plasmid transfection (P < 0.05). The overall apoptosis rate was 37.6% ± 2.3% in the co-transfection group, 20.0% ± 0.4% in the survivin shRNA group, and 21.6% ± 1.6% in the CD44v3 shRNA group. Combined transfection induced cell apoptosis more efficiently than single-plasmid transfection (P < 0.05). The number of cells passing the Transwell chamber was 66.12 ± 4.04 in the co-transfection group, 89.35 ± 3.06 in the survivin shRNA group, and 93.53 ± 5.13 in the CD44v3 shRNA group. Combined transfection reduced cell invasion more significantly than single-plasmid transfection (P < 0.05).

CONCLUSION: Transfection of either survivin shRNA or CD44v3 shRNA could significantly inhibit cell proliferation, reduce cell invasion and induce cell apoptosis in human colorectal carcinoma cell line SW480. Co-transfection of survivin and CD44v3 shRNAs has a synergistic effect in inhibiting proliferation and weakening invasion of SW480 cells.

Up-regulation of survivin in oral squamous cell carcinoma correlates with poor prognosis and chemoresistance

Survivin, a key member of the inhibitor of apoptosis protein family, has been reported to be capable of regulating both cellular proliferation and apoptotic cell death. This protein is found to be overexpressed in many human cancers. The aim of this study was to evaluate the prognostic significance of survivin mRNA expression in oral squamous cell carcinoma (OSCC) and to analyze its correlation with chemoresistance. Reverse-transcription polymerase chain reaction assay was performed to detect the expression of survivin mRNA in OSCC cell lines or tissue samples. Immunohistochemistry was performed to detect the expression of survivin protein in OSCC tissues or corresponding nontumor tissues. Then the correlation between survivin mRNA expression and clinicopathologic features or prognosis of OSCC patients was analyzed. Small interfering RNA technology was used to down-regulate the expression of the survivin gene in the OSCC cell line. Methylthiazol tetrazolium and flow cytometric assays were performed to detect proliferation and apoptosis of the OSCC cell line (HSC-3). Furthermore, the effect of small interfering RNA (siRNA) targeting survivin on the sensitivity of OSCC cells to chemotherapeutic agents (cisplatin and 5-fluorouracil [5-FU]) was determined. Results showed that the levels of survivin mRNA expression were significantly higher in OSCC cells or tissues than those in normal human oral keratinocyte or corresponding noncancerous tissues. The immunostaining of survivin protein was significantly stronger in OSCC tissues than in corresponding nontumor tissues. Moreover, high survivin mRNA expression was correlated with poorer tumor differentiation, higher clinical stage, and the presence of lymph node metastasis (P < .05). Multivariate analysis showed that the status of survivin mRNA could be an independent prognostic factor for OSCC patients (hazard ratio 2.71, 95% confidence interval 1.46-5.10; P = .012). In addition, siRNA-mediated survivin down-regulation could significantly inhibit proliferation and induce apoptosis of OSCC cells. Suvivin down-regulation could also significantly enhance chemosensitivity of OSCC cells, which was associated with apoptosis enhancement. Thus, the status of survivin mRNA expression was a potential prognostic factor for OSCC patients, and siRNA-mediated survivin down-regulation could become a novel strategy for chemosensitization of human OSCCs.

Prognostic significance of nuclear survivin expression in resected adenoid cystic carcinoma of the head and neck

OBJECTIVES

The expression of survivin, an inhibitor of apoptosis, in tumor cells is associated with poor clinical outcome for various cancers. We conducted this study to determine survivin expression in patients with adenoid cystic carcinoma (ACC) of the head and neck and to identify its clinical significance as a prognostic factor.

MATERIALS AND METHODS

We performed immunohistochemical staining for survivin, p53, bcl-2 protein, and Ki-67 in formalin fixed, paraffin-embedded blocks from 37 cases of head and neck ACC. We also reviewed the patients' clinical records to determine the association of staining with clinical course.

RESULTS

Of the 37 cases of head and neck ACC, 31 (83.8%) were positive for cytoplasmic survivin expression, and 23 (62.2%) were positive for nuclear survivin expression. There was a significant association between nuclear survivin expression and bcl-2 (P = 0.031). A larger tumor was more commonly a survivin-positive tumor (cytoplasmic survivin, P = 0.043; nuclear survivin, P = 0.057). Median overall survival (OS) was significantly longer in patients not expressing nuclear survivin (P = 0.035). A multivariate analysis revealed that nuclear survivin expression significantly impacted OS (hazard ratio 8.567, P = 0.018) in addition to lymph node involvement (hazard ratio 7.704, P = 0.016).

CONCLUSIONS

The immunohistochemical expression of nuclear survivin has a prognostic impact in patients with head and neck ACC. These results suggest that nuclear survivin expression may be a useful biomarker for predicting prognosis in patients with head and neck ACC who were treated with surgical resection.

Survivin expression in colorectal carcinomas: correlations with clinicopathological parameters and survival

BACKGROUND

Survivin is a new member of the Inhibitor of apoptosis protein family that has a dual function as a mitotic regulator and apoptosis inhibitor. Survivin is prominently expressed in transformed cell lines and in many human cancers, including colorectal carcinoma. The aim of this study is to investigate the expression of survivin in colorectal carcinomas and its possible associations with clinicopathological parameters and patient survival.

MATERIALS AND METHODS

Sections of formalin-fixed paraffin-embedded tissues from 77 colorectal carcinomas were immunohistochemistry stained for survivin.

RESULTS

Survivin was mainly detected in the bottom of the glands of normal mucosa with mainly cytoplasmic localization. No survivin expression was found in infiltrating lymphocytes, fibroblasts, smooth muscle cells or neural tissue. Survivin staining was detected in 68/77 (88.3%) colorectal carcinomas. Survivin expression was found to be significantly associated with tumor differentiation (P = 0.02) but not with gender, age or Dukes stage. Survival did not differ according to survivin expression.

CONCLUSION

Survivin was found in the majority of colorectal carcinomas, suggesting that its expression is an early event in colorectal carcinogenesis. Its expression is statistically significantly associated with tumor differentiation but not with patient survival.

Combined analysis of survivin autoantibody and carcinoembryonic antigen biomarkers for improved detection of colorectal cancer

BACKGROUND

Survivin is a member of the family of inhibitor of apoptosis proteins that is overexpressed in several human tumors. Previous studies have found that overexpression of survivin in cancer cells induces an antibody response.

METHODS

We compared 232 serum samples from colorectal cancer (CRC) patients and 365 samples from healthy volunteers using an in vitro enzyme-linked immunosorbent assay to evaluate the survivin autoantibody response in patients.

RESULTS

The sensitivity of the anti-survivin response from patients with CRC was 56.9%, and the specificity was 64.1%. When a cut-off value of 5.0 ng/mL was chosen for carcinoembryonic antigen (CEA) in these same serum samples, the values for sensitivity and specificity were 40.9% and 86.6%, respectively. Combined detection using survivin autoantibodies and CEA produced better sensitivity (51.3%) and specificity (89.9%) compared to the sensitivity of CEA (40.9%) and the specificities of the individual markers (64.1% and 86.6%, respectively). The area under a receiver operating characteristic curve was 0.617 for survivin autoantibodies, 0.630 for CEA and 0.694 for both markers together.

CONCLUSIONS

A positive association between autoantibodies against survivin and preoperative CEA concentrations in sera of patients with CRCs was established. Our results suggest that analysis of both parameters would assist in screening patients with CRC.

Development of cetuximab-resistant human nasopharyngeal carcinoma cell lines and mechanisms of drug resistance

This work aimed to explore the induction of cetuximab-resistant human nasopharyngeal carcinoma (hNPC) 5-8F/Erbitux cells and the mechanisms of drug resistance. The 5-8F cells with high EGFR expression and cetuximab sensitivity were screened and then induced by stepwise exposure to increasing doses of cetuximab. Western blot was conducted to detect protein levels. Our results are as follows: we successfully induced the cetuximab-resistant 5-8F/Erbitux hNPC cells. After treatment with cetuximab for 3 and 5 days, the RI was 1.2 and 1.1, respectively. The 5-8F/Erbitux cells showed cross-resistance to 5-FU (P<0.01) and some resistance to Taxol (P>0.05) as well as enhanced sensitivity to DDP (P>0.05). The cells had increased levels of P-gP, IGF-1R, P-IGF-1R, K-ras, H-ras, and PTEN protein expression (P<0.001), while survivin decreased (P<0.001). Through sequence alignments, gene mutations in the PTEN gene at exons 5, 7, and 8, as well as the H-ras and K-ras genes in codons 12, 13, 59, and 61, were not observed. After transfection with H-ras-shRNA plasmid, the 5-8F/Erbitux cells showed reduced levels of gene and protein expression of H-ras and elevated sensitivity to cetuximab. In conclusion, gene amplification and overexpression of H-ras was the major mechanism that caused resistance of 5-8F/Erbitux cells to cetuximab, while the overexpression of the H-ras gene was probably associated with the over-activity of the IGF-1R signaling pathway. Gene deletion or mutation of PTEN was not associated with resistance of 5-8F/Erbitux cells to cetuximab.

Reg IV regulates normal intestinal and colorectal cancer cell susceptibility to radiation-induced apoptosis

BACKGROUND & AIMS

Regenerating (Reg) gene IV is predominantly expressed in gastrointestinal cells and highly up-regulated in many gastrointestinal malignancies, including colorectal cancer (CRC). Human CRC cells expressing higher levels of Reg IV gene and its protein product (Reg IV) are resistant to conventional therapies, including irradiation (IR). However, the underlying mechanism is not well defined.

METHODS

A murine model of IR-induced intestinal injury and in vitro and in vivo models of human CRC were used to determine the role of Reg IV in regulation of normal intestinal and colorectal cancer cell susceptibility to IR-induced apoptosis.

RESULTS

Treatments of recombinant human Reg IV (rhR4) protein protected normal intestinal crypt cells from IR-induced apoptosis by increasing the expression of antiapoptotic genes Bcl-2, Bcl-XL, and survivin. However, overexpression of Reg IV in human CRC cells was associated with increased resistance to IR-induced apoptosis. Therefore, we used antagonism of Reg IV as a tool to increase CRC cell susceptibility to IR-induced cell death. Two complementary approaches using specific monoclonal antibodies and small interfering RNAs were tested in both in vitro and in vivo models of human CRC. Both approaches resulted in increased apoptosis and decreased cell proliferation, leading to decreased tumor growth and increased animal survival. Furthermore, these approaches increased CRC cell susceptibility to IR-induced apoptosis.

CONCLUSIONS

These results implicate Reg IV as an important modulator of gastrointestinal cell susceptibility to IR; hence, it is a potential target for adjunctive treatments for human CRC and other gastrointestinal malignancies.

Serum and urine survivin levels in breast cancer

This study was conducted to investigate the serum and urine levels of survivin in patients with breast cancer and the relationships with known prognostic parameters and therapy. Forty-three patients with breast cancer and 21 healthy control subjects were investigated. Serum samples were obtained on the first admission before adjuvant and metastatic treatment were given and after two cycles of chemotherapy. Serum and urine survivin levels were determined using enzyme immunometric assay (EIA) and enzyme-linked immunosorbent assay (ELISA), respectively. There was no significant difference in the baseline serum and urine levels between patients with breast carcinoma and healthy controls (p = 0.19 and p = 0.84, respectively). None of the prognostic parameters analyzed were significantly correlated with the urine survivin concentrations. This was also true for serum survivin values, except for nodal involvement. Serum survivin levels were significantly higher in the patients with nodal involvement compared with node negatives (p = 0.043). However, serum survivin levels were not influenced by the number of involved nodes (p = 0.77). No significant correlation was found between the serum and urine levels of survivin (r = 0.15, p = 0.27). Serum and urine levels did not change significantly after chemotherapy (p = 0.59 and p = 0.50, respectively). In conclusion, the result of this study suggested that serum survivin level could be a sensitive marker for detecting metastases in lymph nodes from breast cancer patients. However, much research continues in this field, and exciting new knowledge will ultimately emerge.

Survivin and Smac gene expressions but not livin are predictors of prognosis in non-small cell lung cancer patients treated with adjuvant chemotherapy following surgery

OBJECTIVE

Survivin and livin, which are members of the inhibitor of apoptosis protein family, regulate both programmed cell death and proliferation. Second mitochondria-derived activator of caspase is thought to regulate apoptosis by antagonizing inhibitor of apoptosis protein. These gene expressions are regarded as prognostic markers in some malignancies. However, result in previous studies of the association of these gene expressions with prognosis of patients with non-small cell lung cancer remains contradictory.

METHODS

Survivin, livin and second mitochondria-derived activator of caspase mRNA was detected by semi-quantitative reverse transcriptase-polymerase chain reaction in surgical resected tumor specimen from 66 non-small cell lung patients who received adjuvant platinum-based chemotherapy.

RESULTS

Results showed that patients with survivin high expression had significantly shorter tumor-free survival (P = 0.012) and overall survival (P = 0.007) than those with survivin low expression. There was a significant association of second mitochondria-derived activator of caspase high expression in non-small cell lung cancer tissue with longer tumor-free survival (P = 0.021) and overall survival (P = 0.0013). However, livin mRNA expression level had no impact on the tumor-free survival and overall survival of the patients. In multivariate analyses, survivin mRNA high expression (P = 0.033 and P = 0.024) and advanced pathologic stage (P = 0.009 and P = 0.008) were the factors which independently predicted a worse tumor-free survival and overall survival.

CONCLUSIONS

Our data suggest that assessment of survivin and second mitochondria-derived activator of caspase mRNA expression may be useful for predicting survival in non-small cell lung cancer patients receiving platinum-based chemotherapy after surgical resection and can provide valuable information for deciding better therapy strategy.

Inhibitor of differentiation 1 contributes to head and neck squamous cell carcinoma survival via the NF-kappaB/survivin and phosphoinositide 3-kinase/Akt signaling pathways

PURPOSE

A key issue in cancer is apoptosis resistance. However, little is known about the transcription factors that contribute to cellular survival of head and neck squamous cell carcinoma (HNSCC).

EXPERIMENTAL DESIGN

Three batches (54, 64, and 38) of HNSCC specimens were used for cellular and molecular analyses to determine the major molecular signaling pathways for cellular survival in HNSCC. Animal models (cell culture and xenografts) were used to verify the importance of apoptosis resistance in HNSCC.

RESULTS

Inhibitor of differentiation (Id) family member, Id1, was significantly upregulated in clinical HNSCC specimens and acted to protect keratinocytes from apoptosis. Transfection of HNSCC cells with Id1 in vitro induced the phosphorylation of Akt (p-Akt) via phosphoinositide 3-kinase and increased the expression of survivin via NF-kappaB. Blockage of both pathways by specific inhibitors (LY294002 and IkappaBalphaM, respectively) abrogated Id1-induced cell survival of keratinocytes. In vivo studies showed that increased expression of Id1 allowed nontumorigenic keratinocytes (Rhek-1A) to become tumorigenic in nude mice by increased expression of survival genes such as p-Akt and survivin. More importantly, short interfering RNA for Id1 significantly reduced HNSCC tumor volume of HNSCC in xenograft studies. Analysis of clinical data verified the importance of the Id1 downstream molecule, survivin, in the prognosis of HNSCC patients.

CONCLUSIONS

The above data, taken together, suggest that Id1 and its downstream effectors are potential targets for treatment of HNSCC because of their contribution to apoptosis resistance.

DcR3 and survivin are highly expressed in colorectal carcinoma and closely correlated to its clinicopathologic parameters

OBJECTIVE

To investigate the expression of death decoy receptor 3 (DcR3) and survivin in colorectal carcinoma.

METHODS

Tumor and normal tissues were taken from a total of 100 colorectal carcinoma patients during surgery, and the expression of DcR3 and survivin was examined by immunohistochemistry, Western blotting, and reverse transcription-polymerase chain reaction (RT-PCR) analyses.

RESULTS

RT-PCR showed that the expression levels of DcR3 mRNA (0.846+/-0.242, P<0.01) and survivin mRNA (0.7835+/-0.2392, P<0.01) in colorectal cancer tissues were significantly higher than those in adjacent normal tissues. Western blotting showed that the expression levels of DcR3 protein (0.795+/-0.261, P<0.01) and survivin protein (0.6765+/-0.1351, P<0.01) in tumor tissues were significantly higher than those in non-cancer tissues. The immunohistochemical streptavidin-peroxidase (SP) method showed that the positive expression rates of DcR3 and survivin were 67.0% and 58.0% in colorectal cancer tissues, and 18.0% and 3.0% in non-cancerous colorectal tissues (P<0.05), respectively. The positive correlations of DcR3 (P<0.01) and survivin (P<0.01) to the differentiation of colorectal carcinoma cells, lymph node metastasis, and pathological stage were observed. The expression of DcR3 and survivin was found to be positively correlated to clinicopathologic parameters of colorectal carcinoma.

CONCLUSION

The overexpressed DcR3 and survivin in colorectal cancer may contribute to the development of the cancer. The monitoring of these two proteins may be useful for the diagnosis, differentiation, metastasis, and determination of stages of colorectal carcinoma.