Survivin -31C/G polymorphism and gastric cancer risk in a Brazilian population

The survivin molecule as a double-edged sword in cellular physiologic and pathologic conditions and its role as a potential biomarker and therapeutic target in cancer

Survivin is a member of the family of apoptosis inhibitory proteins with increased expression level in most cancerous tissues. Evidence shows that survivin plays regulatory roles in proliferation or survival of normal adult cells, principally vascular endothelial cells, T lymphocytes, primitive hematopoietic cells, and polymorphonuclear neutrophils. Survivin antiapoptotic role is, directly and indirectly, related to caspase proteins and shows its role in cell division through the chromosomal passenger complex. Survivin contains many genetic polymorphisms that the role of some variations has been proven in several cancers. The -31G/C polymorphism is one of the most important survivin mutations which is located in the promoter region on a CDE/CHR motif. This polymorphism can upregulate the survivin messenger RNA. In addition, its allele C can increase the risk of cancers in 1.27-fold than allele G. Considering the fundamental role of survivin in different cancers, this protein could be considered as a new therapeutic target in cancer treatment. For this purpose, various strategies have been designed including the prevention of survivin expression through inhibition of mRNA translation using antagonistic molecules, inhibition of survivin gene function through small inhibitory molecules, gene therapy, and immunotherapy. In this study, we describe the structure, played roles in physiological and pathological states and genetic polymorphisms of survivin. Finally, the role of survivin as a potential target in cancer therapy given challenges ahead has been discussed.

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.

Survivin Promoter Polymorphism (-31 C/G): A Genetic Risk Factor for Oral Cancer

Background: The polymorphism of survivin gene at its promoter region is one of the risk factors for OSCC . This polymorphism involves substitution of G for C (9904341), and it is present at the cell cycle dependent elements and cell cycle homology region repressor binding motif of promoter. This study aimed to find the association between survivin -31C/G polymorphism and prevalence of OSCC in a subset of Pakistani population. Methodology: This case-control study was conducted on 47 cases with and 101 healthy individuals with no family history of cancer. We used polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) protocols. Results: The most common site of oral cancer in our research was the buccal mucosa followed by tongue and the least one was the labial mucosa. The histological tumor type of all 47 cases was squamous cell type. In our research, stage II had the highest prevalence, accounting for 34% of patients, while the prevalence of stage I was 31% in the case group. The prevalence of stage III and IV was 25% and 8%, respectively. The numbers of moderately and poorly differentiated tumors were equal. We found a significant association between the CC genotype of survivin and OSCC prevalence (OR was 9.395 at 95% CI: 1.0202-86.5251, p-value= 0.04). The GG genotype also showed significant P value (OR: 0.4709 with 95% CI: 0.2323- 0.9546 at a P VALUE of 0.0367). while no significant P value was noted for CG genotype (OR: 1.4317 with 95% CI: 0.7513 -2.8658, p- value= 0.31). Conclusion: Survivin -31G/C polymorphism was strongly associated with OSCC prevalence. The C allele was more common in case group as compared to healthy individuals living in Pakistan.

Survivin rs9904341 polymorphism significantly increased the risk of cancer: evidence from an updated meta-analysis of case-control studies

AIMS

Survivin, a member of inhibitor of apoptosis protein family, is involved in the regulation of cell cycle and apoptosis. Several studies inspected the association between survivin polymorphisms and the risk of various cancers, but the findings remain controversial. We conducted a meta-analysis intending to certify the association between survivin polymorphisms and cancer risk.

METHODS

All analyses were achieved using RevMan 5.3 software and STATA 14.1 software. Eligible studies were collected by comprehensive literature searching Web of Science, PubMed, Scopus, and Google scholar databases. Pooled estimates of odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the overall impact of survivin polymorphisms on cancer risk.

RESULTS

The overall analysis indicates that survivin rs9904341 polymorphism significantly increased the risk of cancer in homozygous codominant (OR 1.41, 95% CI 1.19-1.68, p = 0.0001, CC vs GG), dominant (OR 1.22, 95% CI 1.07-1.40, p = 0.003, CG+CC vs GG), recessive (OR 1.34, 95% CI 1.18-1.52, p < 0.0001, CC vs CG+GG), and allele (OR 1.20, 95% CI 1.09-1.31, p = 0.0001, C vs G) inheritance models tested. Stratified based on ethnicity revealed that rs9904341 variant significantly increased the risk of cancer in the Asian population. The findings did not support an association between rs1042489, rs2071214, rs8073069, and rs17878467 polymorphisms and risk of cancer.

CONCLUSIONS

The current study suggests that the survivin rs9904341 polymorphism may be associated with the risk of cancer either overall or in the Asian population. However, further larger and well-designed studies are warranted to evaluate this association in detail.

Significance of Serum Survivin and -31G/C Gene Polymorphism in the Early Diagnosis of Breast Cancer in Egypt

BACKGROUND

Breast cancer is one of the most relevant malignancies among women. Molecular abnormalities in promotor region of survivin gene may account for overexpression of survivin and increased breast cancer risk. This study aimed to explore the potential association between survivin promotor gene -31G/C single nucleotide polymorphism (rs9904341) and its serum level alteration on one hand, and the risk of breast cancer in Egyptian patients on the other hand. It also aimed to assess the usefulness of survivin as an early noninvasive diagnostic biomarker and in breast cancer staging.

PATIENTS AND METHODS

A total of 135 patients with physically and pathologically confirmed breast cancer and 40 unrelated control subjects as well as 40 patients with benign breast mass were recruited from the early detection unit at National Cancer Institute, Cairo University. Genotyping was performed using allelic discrimination probes by real-time quantitative PCR and serum survivin by enzyme-linked immunosorbent assay.

RESULTS

The minor allele C of -31G/C survivin single nucleotide polymorphism was more frequent in breast cancer patients (19.3%) compared to the control group (7.5%). Furthermore, subjects with the GC + CC genotype were at increased risk of breast cancer compared to the GG genotype of the control group and also the benign group. Moreover, those patients exhibited higher serum levels of survivin compared to GG genotype. There was also significant elevation of serum survivin in different breast cancer stages.

CONCLUSION

Genetic variation in -31G/C of the survivin gene may contribute to the disposition of breast cancer in the Egyptian population. Serum survivin alteration played a pivotal role in the pathogenesis of breast cancer.

Survivin expression in canine spontaneous cutaneous and subcutaneous tumors and its prognostic importance

AIM

The present study was carried out to know the expression level of survivin, an inhibitor of apoptosis protein with an objective to determine its prognostic importance in cutaneous and subcutaneous tissue tumors of dogs.

MATERIALS AND METHODS

Forty cases of canine cutaneous and subcutaneous tissue tumors on histopathological examination revealed various round cell, epithelial, and mesenchymal cell tumors. Survivin gene expression was detected in all tumors tested by TaqMan real-time polymerase chain reaction assay by comparative cycle threshold method.

RESULTS

The mean survivin gene expression value of benign tumors was 0.94±0.63 folds and that of malignant tumors was 18.87±5.30 folds. Postsurgical follow up of 30 malignant tumor cases revealed death in 8, recurrence in 7, and neoplastic free alive status in 15 dogs with mean survivin fold difference values of 48.49±12.39, 14.63±6.37, and 5.034±2.27, respectively. The mean survivin gene expression value was significantly higher in malignant (30 cases, 18.87±5.30) compared to benign tumors (10 cases, 0.94±0.63), and it varied between various postsurgical follow-up groups (p<0.05). Survival analysis, using survivin gene expression median cutoff value of 3.74 in 30 malignant tumors, was performed to predict probable survival period in malignant cutaneous and subcutaneous tumors of dogs.

CONCLUSIONS

Results of the present study indicated that the expression of survivin in canine cutaneous and subcutaneous tumors has prognostic value, and survivin expression greater than median cutoff value of 3.74 has a poor prognosis.

The anti-apoptotic protein survivin can improve the prognostication of meningioma patients

BACKGROUND

The 2016 WHO histopathological grading includes a substantial within-variation in recurrence risk, and is thus insufficient to predict prognosis after initial surgery of patients suffering from meningiomas. The aim of this study was to compare the prognostic value of the histopathological grading and the conventional biomarker MIB-1 with expression of the anti-apoptotic protein survivin to see if this biomarker could complement recurrence prediction.

METHODS

Using immunohistochemistry, the expression of MIB-1 and survivin were determined as labeling indices (LIs) in tissue micro arrays from 160 human meningiomas. The accuracy of prognostication was assessed with receiver operator characteristics analyses and standard survival analyses.

RESULTS

The expression of survivin was significantly associated with both histopathological grade (P = 0.022) and recurrence status (P = 0.035). A survivin LI of 1% was identified as the optimal cutoff value to predict recurrence (P = 0.003), and was proven as more reliable than the histopathological grading (P = 0.497) and MIB-1 expression (P = 0.091). This result was further strengthened in multivariate analyses where survivin expression was revealed as an independent predictor of recurrence-free survival, while the histopathological grading and MIB-1 expression did not reach significance (P ≥ 0.156).

CONCLUSIONS

These findings suggest that incorporation of survivin in the clinical practice might be useful as complement for the histopathological grading and should further be evaluated in independent prospective studies.

Survivin: A molecular biomarker in cancer

Survivin, a member of the inhibitor of apoptosis (IAP) protein family that inhibits caspases and blocks cell death, is highly expressed in most cancers and is associated with a poor clinical outcome. Survivin has consistently been identified by molecular profiling analysis to be associated with high tumour grade cancers, different disease survival and recurrence. Polymorphisms in the survivin gene are emerging as powerful tools to study the biology of the disease and have the potential to be used in disease prognosis and diagnosis. The survivin gene polymorphisms have also been reported to influence tumour aggressiveness as well as survival of cancer patients. The differential expression of survivin in cancer cells compared to normal tissues and its role as a nodal protein in a number of cellular pathways make it a high target for different therapeutics. This review discusses the complex circuitry of survivin in human cancers and gene variants of survivin, and highlights novel therapy that targets this important protein.

Role of gene polymorphisms in gastric cancer and its precursor lesions: Current knowledge and perspectives in Latin American countries

Latin America shows one of the highest incidence rates of gastric cancer in the world, with variations in mortality rates among nations or even within countries belonging to this region. Gastric cancer is the result of a multifactorial complex process, for which a multistep model of carcinogenesis is currently accepted. Additionally to the infection with Helicobacter pylori, that plays a major role, environmental factors as well as genetic susceptibility factors are significant players at different stages in the gastric cancer process. The differences in population origin, demographic structure, socio-economic development, and the impact of globalization lifestyles experienced in Latin America in the last decades, all together offer opportunities for studying in this context the influence of genetic polymorphisms in the susceptibility to gastric cancer. The aim of this article is to discuss current trends on gastric cancer in Latin American countries and to review the available published information about studies of association of gene polymorphisms involved in gastric cancer susceptibility from this region of the world. A total of 40 genes or genomic regions and 69 genetic variants, 58% representing markers involved in inflammatory response, have been used in a number of studies in which predominates a low number of individuals (cases and controls) included. Polymorphisms of IL-1B (-511 C/T, 14 studies; -31 T/C, 10 studies) and IL-1RN (variable number of tandem repeats, 17 studies) are the most represented ones in the reviewed studies. Other genetic variants recently evaluated in large meta-analyses and associated with gastric cancer risk were also analyzed in a few studies [e.g., prostate stem cell antigen (PSCA), CDH1, Survivin]. Further and better analysis centered in gene polymorphisms linked to other covariates, epidemiological studies and the information provided by meta-analyses and genome-wide association studies should help to improve our understanding of gastric cancer etiology in order to develop appropriate health programs in Latin America.

Survivin gene promoter polymorphisms: Clinical significance and association with susceptibility to colon cancer

AIM: To investigate the clinical significance of survivin gene promoter polymorphisms and their association with susceptibility to colon cancer.

METHODS: The -31G/C, -241T/C, -625G/C and -644T/C single nucleotide polymorphisms in the survivin gene promoter region were genotyped in 217 colon cancer specimens and 198 normal people specimens by PCR-RFLP.

RESULTS: The frequency of the -31G/C locus containing the G allele (CG + GG) in colon cancer patients (60.8%) was significantly lower than that in the normal control group (60.8% vs 72.7%, P = 0.010, OR = 0.582, 95%CI: 0.385-0.882). The -31G/C site G variation was associated with tumor differentiation (P = 0.019), extent of tumor invasion (P = 0.008), and distant metastasis (P = 0.0008). Other three survivin polymorphisms had no significant differences between the colon cancer group and normal control group, and showed no significant correlation with tumor differentiation, tumor invasion, lymph node metastasis or tumor distant metastasis.

CONCLUSION: The -31G/C locus carrying the G allele significantly decreases susceptibility to colon cancer, and the G variant genotype is a protective factor against colon cancer.

Association between survivin -31G>C polymorphism and cancer risk: meta-analysis of 29 studies

PURPOSE

A growing body of evidence has shown the possible relevance of survivin -31G>C (rs9904341) promoter polymorphism to the genetic susceptibility of cancer. Because of the lack of available conclusive data, we performed a meta-analysis of all relevant available studies to derive a more precise estimation of the relationship.

METHODS

A comprehensive literature search of Medline electronic database was conducted to collect relevant studies until August 18, 2013. References of the retrieved articles were also screened. The extracted data were statistically analyzed, and pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated to estimate the association strength using Stata version 11.2 software.

RESULTS

A total of 29 studies with 7,473 cancer cases and 9,086 controls were included in the meta-analysis. Overall, the pooled analysis revealed that suvivin -31G>C polymorphism was significantly associated with increased cancer risk under multiple genetic models (CC vs. GG: OR = 1.37, 95 % CI 1.06–1.76; CC vs. CG: OR = 1.27, 95 % CI = 1.10–1.46; CC vs. CG + GG: OR = 1.31, 95 % CI = 1.10–1.57). In subgroup analysis with different cancer types, the -31G>C polymorphism significantly increased the risk of colorectal, gastric, and urothelial cancers, while this SNP remarkably decreased the susceptibility to hepatocellular carcinoma. Further stratification analysis by ethnicity showed an increasing cancer risk in the Asian population (CC vs. GG: OR = 1.61, 95 % CI 1.17–2.21; CC vs. CG: OR = 1.31, 95 % CI 1.12–1.53; CC vs. CG + GG: OR = 1.43, 95 % CI 1.16–1.77) but not in Europeans.

CONCLUSIONS

The survivin -31G>C polymorphism is associated with elevated cancer risk, especially among colorectal, gastric, and urothelial cancers and Asian populations.

Apoptotic mediators in patients with severe and non-severe dengue from Brazil

Despite being the most significant arboviral disease worldwide, dengue has no antiviral treatment or reliable severity predictors. It has been shown that apoptotic cells from blood and tissues may be involved in the complex pathogenesis of dengue. However, very little is known about the interplay between proapoptotic and antiapoptotic mediators in this disease. Therefore, plasma levels of the three proapoptotic mediators Fas ligand (FasL), tumor necrosis factor‐α (TNF‐α), and TNF‐related apoptosis‐inducing ligand (TRAIL) were measured in dengue patients. Patients were classified according to the World Health Organization classification of dengue revised in 2009. Additionally, inhibitors of apoptosis protein (IAPs) were determined in plasma (Survivin) and peripheral blood mononuclear cells (PBMCs) lysates (cIAP‐1, cIAP‐2, XIAP). Levels of apoptotic proteins in plasma were correlated with counts of blood cells. FasL and TRAIL levels were elevated in dengue patients without warning signs when compared to patients with severe dengue and controls. Dengue patients with warning signs showed decreased levels of Survivin compared to patients with severe dengue and controls. TRAIL was inversely correlated with counts of lymphocyte subsets. In contrast, Survivin was positively correlated with leukocyte counts. There was a trend of elevated IAPs levels in PBMCs of patients with severe dengue. The results suggest a likely antiviral effect of TRAIL in dengue. It appears that TRAIL might be involved with apoptosis induction of lymphocytes, whereas IAPs might participate in protecting leukocytes from apoptosis. Further research is needed to explore the interactions between pro and antiapoptotic molecules and their implications in dengue pathogenesis. J. Med. Virol. 86:1437–1447, 2014. © 2013 Wiley Periodicals, Inc.

Survivin rs9904341 (G>C) polymorphism contributes to cancer risk: an updated meta-analysis of 26 studies

Survivin, a member of the inhibitor of apoptosis protein family, encoded by BIRC5, is involved in the regulation of apoptosis and in cell cycle control. Emerging evidences indicate that polymorphism in BIRC5 promoter (rs9904341) is associated with cancer risk, but the results of individually published studies are inconclusive. Thus, an updated meta-analysis was performed. PubMed was searched for all eligible studies. Pooled odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated to assess the association strength. Stratified analysis was performed by cancer type, source of control, genotyping method, and ethnicity. A number of 26 studies, including 6,041 cases and 7,567 controls were analyzed in this meta-analysis. Overall, significantly increased cancer risk was associated with survivin rs9904341 polymorphism when all studies were pooled (CC vs. GG: OR = 1.36, 95 % CI = 1.09-1.69; P heterogeneity < 0.001; CC vs GC/GG: OR = 1.32, 95 % CI = 1.11-1.57; P heterogeneity < 0.001). Stratified analysis by cancer type revealed that the survivin rs9904341 polymorphism may increase the risk of colorectal cancer, renal cell cancer, gastric cancer, and bladder cancer. Further subgroup analysis by ethnicity indicated that there was a statistically increased cancer risk in Asians but not Caucasians. In this updated meta-analysis of 26 studies, we conclude that the survivin rs9904341 polymorphism might contribute to risk of various cancers, especially in Asian populations.

Association of survivin polymorphisms with tumor susceptibility: a meta-analysis

Background

The survivin polymorphisms have been shown to confer genetic susceptibility to various tumors, but the results are inconsistent. In order to accomplish a more precise estimation of the relationship, a meta-analysis was performed.

Results

For rs9904341, a significantly increased tumor risk was found in overall meta-analysis under C/C vs. G/G (OR = 1.40, 95% CI = 1.13–1.74, p = 0.002), dominant (OR = 1.18, 95% CI = 1.01–1.38, p = 0.039) and recessive (OR = 1.34, 95% CI = 1.13–1.58, p = 0.001) genetic models and Asians group. In subgroup analyses of tumor types, we found a significant association between this SNP and an increased risk of gastric, colorectal, bladder and other tumors as well as a decreased risk of hepatocellular cancer. For rs17878467, a significantly decreased tumor risk was identified in overall meta-analysis for allele contrast (T vs. C: OR = 0.69, 95% CI = 0.51–0.92, p = 0.012), C/T vs. C/C (OR = 0.61, 95% CI = 0.42–0.88, p = 0.009) and dominant (OR = 0.62, 95% CI = 0.43–0.88, p = 0.007) genetic models and Asians group. For rs2071214, we found a significant association between this SNP and an increased tumor risk in overall meta-analysis under G/G vs. A/A (OR = 1.51, 95% CI = 1.04–2.18, p = 0.029) and recessive (OR = 1.54, 95% CI = 1.07–2.22, p = 0.020) genetic models and Asians group. Besides, there was a significant association of rs8073069 with an increased tumor risk under recessive genetic model (OR = 1.37, 95% CI = 1.01–1.84, p = 0.040), while no significant association between rs1042489 and tumor risk was detected.

Conclusions

The survivin rs9904341 most likely contributed to increased susceptibility to tumor in Asians as well as to gastric, colorectal and bladder cancers. As for rs17878467, the T allele might be a protective factor for tumor, especially in Asians. Moreover, the survivin rs8073069 and rs2071214 seemed to be associated with an increased tumor risk in Asians, while there was no association between the survivin rs1042489 and tumor risk.

Functional promoter -31G/C variant of Survivin gene predict prostate cancer susceptibility among Chinese: a case control study

Background

Abnormal expression of Baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5, also called as survivin), a novel member of the inhibitor of apoptosis protein (IAP) family, has implications in many types of cancer and is considered as a new therapeutic target. We suppose that genetic variant rs9904341 in the 5′ UTR region of survivin gene may be associated with the development and progression of prostate cancer (PCa) in Chinese population.

Methods

TaqMan assay method was used to genotype the polymorphism in the hospital-based case–control analysis of 665 patients with PCa and 710 age-matched cancer-free controls. The genetic associations with the occurrence and progression of PCa were calculated by logistic regression.

Results

Our results indicated that compared with GG genotypes, there was a statistically significant increased risk of PCa associated with those with CC genotypes [odds ratios (ORs) = 1.57, 95%confidence intervals (CIs) = 1.17-2.13, P = 0.004]. Moreover, stratification analysis revealed that the association was more pronounced in subgroups of nondrinkers, nonsmokers and those without a family history of cancer (all P < 0.05). In addition, we observed that PSA ≥ 20 was more frequent in patients carrying GC/CC genotypes than in those with a wild type genotype.

Conclusion

The functional survivin rs9904341 genetic variant may have a substantial influence on the PCa susceptibility and evolution.

Influence of survivin (BIRC5) and caspase-9 (CASP9) functional polymorphisms in renal cell carcinoma development: a study in a southern European population

Renal cell carcinoma (RCC) is the most common cancer of the adult kidney and its incidence and mortality has increase in the last 20 years. The disruption of cellular death is one the mechanism involved in cancer development. This process is precise regulated by apoptotic and anti-apoptotic molecules. Survivin (BIRC5) is a member of the inhibitor of apoptosis protein family and has the ability to inhibit the activation of the pro-apoptotic caspase-9 (CASP9). Thus BIRC5 and CASP9 functional polymorphisms might modulate the apoptosis and consequently RCC development. Our purpose was to investigate the potential role of BIRC5-31G/C and CASP9+83C/T functional polymorphisms in the risk for the development of RCC and metastatic disease. We studied the BIRC5-31G/C and CASP9+83C/T functional polymorphisms by PCR-RFLP and allelic discrimination using the 7300 real-time polymerase chain reaction system, respectively, in 178 RCC patients and in 305 healthy individuals. Regarding the BIRC5-31G/C polymorphism, there is a trend to an overrepresentation of CC genotype in RCC group compared with normal controls (aOR, 1.94; P=0.053). We observed, after gender stratification and age-adjustment, that BIRC5-31CC and CASP9+83CT/TT genotypes were associated with an increased risk for RCC development in the female group of our southern European study population (aOR=3.85; P=0.019; aOR=2.98; P=0.028; respectively). Concerning the waiting time for onset of metastatic disease, we observed that BIRC5-31CC homozygous developed metastasis 8 years earlier than the G carriers using a Cox proportional hazard model with gender as covariate (HR=4.9, P=0.038, P bootstrap=0.009). The Cox regression proportional hazard model was validated using bootstrap statistic with 1,000 samples of the same number of patients as the original dataset. Our results suggest that individual differences influence the susceptibility to RCC and tumor behavior. This genetic profile may help to define higher risk groups that would benefit from individualized chemoprevention strategies and therapies.

Analysis of the methylation patterns of the p16 INK4A, p15 INK4B, and APC genes in gastric adenocarcinoma patients from a Brazilian population

Gastric cancer is a major public health problem in Pará state, where studies suggest complex genetic and epigenetic profiles of the population, indicating the need for the identification of molecular markers for this tumor type. In the present study, the methylation patterns of three genes [p16 (INK4A), p15 (INK4B), and adenomatous polyposis coli (APC)] were assessed in patients with gastric adenocarcinoma from Pará state in order to identify possible molecular markers of gastric carcinogenesis. DNA samples from tumoral and non-tumoral gastric tissues were modified with sodium bisulfite. A fragment of the promoter region of each gene was amplified and sequenced, and samples with more than 20 % of methylated CpG sites were considered hypermethylated. The correlation between the methylation pattern of the selected genes and the MTHFR C677T polymorphism, as well as the relationship between APC and CDH1 methylation, were evaluated. The results suggest that APC hypermethylation is an age-specific marker of gastric carcinogenesis, and the concordance of this event with CDH1 hypermethylation suggests that the Wnt pathway has an important role in gastric carcinogenesis. While the hypermethylation pattern of p15 (INK4B) seems to be an earlier event in this type of tumor, the hypomethylated status of this gene seems to be correlated to the C677T MTHFR TT genotype. On the other hand, the observed pattern of p16 (INK4A) hypermethylation suggests that this event is a good marker for the gastric cancer pathway in the Pará state population.

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.

Effects of stromal cell-derived factor-1 and survivin gene polymorphisms on gastric cancer risk

Stromal-cell derived factor-1 (SDF-1), a CXC chemokine, is important for growth, angiogenesis and metastasis of tumor cells. The SDF1-3'A polymorphism has been investigated in various types of cancer; however, no information is currently available on its role in gastric cancer. Survivin is a member of the inhibitor of apoptosis family of proteins and has a genetic polymorphism (-31G/C) located in the CDE/CHR repressor element of its promoter. In this study, 88 gastric cancer patients and 480 normal healthy control subjects were investigated for the genotype and allelic SDF1-3'A and survivin -31G/C frequencies using polymerase chain reaction‑restriction fragment length polymorphism. The SDF1-3'A genotype frequencies for GG, GA and AA were 44.32, 48.86 and 6.92% in patients and 42.71, 47.71 and 9.58% in healthy subjects, respectively. GA+AA genotype frequency and A allele distribution were not identified as significantly different between gastric cancer cases and controls. The survivin frequencies for GG, GC and CC were 20.45, 50 and 29.54% in patients and 33.96, 45 and 21.04% in healthy subjects, respectively. The C carriers (GC+CC genotype) and the C allele were over-represented among the gastric cancer cases (P=0.013 and P=0.0083, respectively). Overall, no statistically significant association was identified for SDF-1 and survivin gene examined alleles and genotypes and any parameter investigated, (e.g., stage, differentiation status and survival). The survivin promoter -31G/C polymorphism may confer an increased susceptibility to gastric cancer, while the SDF1-3'A polymorphism may not be a candidate genetic variant to select individuals at higher risk of developing gastric cancer.

Epigenetic mechanisms in gastric cancer

Cancer is considered one of the major health issues worldwide, and gastric cancer accounted for 8% of total cases and 10% of total deaths in 2008. Gastric cancer is considered an age-related disease, and the total number of newly diagnosed cases has been increasing as a result of the higher life expectancy. Therefore, the basic mechanisms underlying gastric tumorigenesis is worth investigation. This review provides an overview of the epigenetic mechanisms, such as DNA methylation, histone modifications, chromatin remodeling complex and miRNA, involved in gastric cancer. As the studies in gastric cancer continue, the mapping of an epigenome code is not far for this disease. In conclusion, an epigenetic therapy might appear in the not too distant future.

Survivin gene promoter polymorphism -31G/C as a risk factor for keratocystic odontogenic tumor development

Several single nucleotide polymorphisms in survivin gene promoters, notably -31G/C, have been shown to modulate the expression and activity of the survivin protein. Consequently, the -31G/C polymorphism has been identified as a risk factor for the development of several types of tumors. The aim of this study was to investigate a possible association between the -31G/C polymorphism and the risk for keratocystic odontogenic tumor (KCOT) development. DNA from 52 biopsy specimens of KCOTs and from 82 buccal swabs of healthy individuals was subjected to PCR restriction fragment length polymorphism analysis to identify individual genotypes. The distribution of genotypes in KCOT and control groups, respectively, was: GG: 30 (57.7%) vs. 26 (31.7%); CG: 17 (32.7%) vs. 45 (54.9%); and CC: 5 (9.6%) vs. 11 (13.4%), respectively. These differences were statistically significant. The G allele was more common in the KCOT group than in the control group: 76 (74%) vs. 96 (59%), respectively. Logistic regression analysis showed that GC heterozygotes had a considerably decreased susceptibility for KCOTs compared with GG homozygotes. The same was true for GC+CC vs. GG. The GG genotype of the -31G/C polymorphism might be a risk factor for KCOT development.

Survivin gene polymorphism association with papillary thyroid carcinoma

Survivin expression is correlated with suppression of apoptosis in human solid tumors. A polymorphism at position -31 (G/C) (rs 9904341) has been associated with cancer risk in several studies. We evaluated the correlation of this polymorphism with the risk of papillary thyroid carcinoma (PTC) in an Irananian population. The cases consisted of patients with PTC (n=123) and normal controls, composed of non-related healthy people (n=131). The frequency of GC or CC genotype in patients with PTC was significantly higher than in the controls [GC+CC vs GG, p=0.02 OR; 1.7, 95%CI (1.05-3.04)]. There was a significant difference between patients with more aggressive clinical manifestations, including lymphatic involvement compared to the controls [GC+CC vs GG, p=0.0006, OR; 3.7, 95%CI (1.6-9.2)]. The presence of C allele was significantly associated with the presence of more profound manifestations, including lymph node involvement, vascular involvement and multifocality.

Association between survivin -31G > C promoter polymorphism and cancer risk: a meta-analysis

Survivin is an inhibitor of apoptosis protein and has a crucial role in the development of cancer. The survivin -31G>C (rs9904341) promoter polymorphism influences survivin expression and has been implicated in cancer risk. However, conflicting results have been published from studies on the association between survivin -31G>C polymorphism and the risk of cancer. To clarify the role of this polymorphism in cancer, we performed a meta-analysis of all available and relevant published studies, involving a total of 3485 cancer patients and 3964 control subjects. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. The overall results indicated that the variant genotypes were associated with a significantly increased cancer risk (CC vs GG: OR=1.58, 95% CI=1.20-2.10; CC/GC vs GG: OR=1.23, 95% CI=1.00-1.51; CC vs GG/GC: OR=1.51, 95% CI=1.23-1.85). In the stratified analyses, significantly increased risk was associated with the Asian populations (CC vs GG: OR=1.67, 95% CI=1.16-2.40; CC vs GG/GC: OR=1.50, 95% CI=1.17-1.91). We also performed the analyses by cancer type, and no statistical association was observed. The results suggest that the survivin -31G>C promoter polymorphism might be associated with an increased risk of cancer, especially in the Asian populations.

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.