Bufotalin enhances apoptosis and TMZ chemosensitivity of glioblastoma cells by promoting mitochondrial dysfunction via AKT signaling pathway.

Glioblastoma multiforme (GBM) is the most prevalent and lethal primary intracranial neoplasm in the adult population, with treatments of limited efficacy. Recently, bufotalin has been shown to have anti-cancer activity in a variety of cancers. This investigation aims to investigate the effect of bufotalin on GBM and elucidate its potential underlying mechanism. Our results show that bufotalin not only inhibits the proliferation and epithelial-mesenchymal transition (EMT) but also triggers apoptosis in GBM cells. The result of RNA-seq indicated that bufotalin could induce mitochondrial dysfunction. Moreover, our observations indicate that bufotalin induces an excessive accumulation of intracellular reactive oxygen species (ROS) in GBM cells, leading to mitochondrial dysfunction and the dephosphorylation of AKT. Moreover, bufotalin improved TMZ sensitivity of GBM cells in vitro and in vivo. In conclusion, bufotalin enhances apoptosis and TMZ chemosensitivity of glioblastoma cells by promoting mitochondrial dysfunction via AKT signaling pathway.

A variant rs6214 within IGF-1 confers risk for ulcerative colitis in Chinese Han populations.

Insulin growth factor-1 (IGF-1) has been found to correlate with various diseases such as cancer and cardiovascular diseases including ulcerative colitis (UC). The present study aimed to investigate the plausible association of rs6214 (C > T) within IGF-1 and UC susceptibility in Chinese Han populations. A total of 977 UC patients and 1029 healthy controls were enrolled, and rs6214 was genotyped with PCR and direct sequencing on the ABI 3730XL DNA analyzer platform. Logistic regression analysis was applied for the correlation of rs6214 and UC susceptibility via calculation of odds ratio (OR) with a 95% confidence interval (95% CI) adjusted for age and sex under different genetic models. The difference of clinical parameters between genotypes was measured by one-way analysis of variance (ANOVA). Additional functional assays were conducted to establish the probable relationship. The results indicated that the T allele of rs6214 showed roughly 37% greater risk for UC risk in the additive model (OR = 1.37, 95% CI = 1.21-1.55, P < 0.000001) when compared with C allele carriers, and the pattern was similar in other three genetic models. Further stratified analysis suggested that the association was particularly noteworthy in UC patients with extensive colitis and severe condition. Moreover, the blood level of IGF-1 was downregulated in UC patients, and the mRNA level was lower in T allele carriers in rectal tissues of UC cases. Additional luciferase assay demonstrated that rs6214 regulates IGF-1 expression via promoting miR-2053. Collectively, rs6214 increased UC susceptibility and suppresses IGF-1 expression by enhancing miR-2053 binding. The current findings provided evidence that rs6214 is a promising biomarker for UC prediction and prognosis.

A functional polymorphism within the distal promoter of RUNX3 confers risk of colorectal cancer.

BACKGROUND: Accumulating evidence has indicated that runt-related transcription factor 3 (RUNX3) gene polymorphism (rs7528484) is associated with an alimentary system cancer risk. However, the role of rs7528484 in colorectal cancer is still unclear. The present study aimed to explore the association between rs7528484 and colorectal cancer susceptibility in a Chinese Han population. MATERIAL AND METHODS: We firstly investigated the effect of the polymorphism rs7528484 in distal promoter of RUNX3 polymorphism on colorectal cancer risk in a Chinese Han population comprising 427 colorectal cancer patients and 503 controls. We then carried out a phenotype-genotype association analysis to validate its influence on the adjacent gene RUNX3. RESULTS: Logistic regression analysis demonstrated that the T allele of rs7528484 was significantly associated with an increased risk for colorectal cancer occurrence in our case-control study (odds ratio = 1.33; 95% confidence interval = 1.09-1.65; P = 0.005). In stratified analysis, the susceptibility of colorectal cancer in the T allele carriers increased among the smokers, III and IV tumor stage, and at the rectum. Furthermore, the T allele was significantly correlated with lower expression of RUNX3 in vitro. CONCLUSION: In summary, the current case-control and genotype-phenotype study provides convincing evidence that functional RUNX3 polymorphism (rs7528484) is related to colorectal cancer risk and is a plausible marker for the prediction of colorectal cancer.

miR-146a rs2910164 polymorphism and the risk of colorectal cancer in Chinese population.

OBJECTIVE: MicroRNAs-associated single nucleotide polymorphisms are thought to play an important role in cancer development. We investigated the association of miR-146a rs2910164 polymorphism with the risk of colorectal cancer (CRC) in Chinese population. MATERIALS AND METHODS: In this hospital-based case-control study of 560 cases and 780 age- and gender-matched healthy controls, the miR-146a rs2910164 polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: We found that miR-146a rs2910164 polymorphism was not associated with CRC risk. However, the subgroup analysis by gender showed significant associations in male subjects (GG vs. CC: Odds ratios [OR] = 1.54, 95% confidence intervals [CI] = 1.04-2.29, P = 0.03; G vs. C: OR = 1.21, 95% CI = 1.01-1.45, P = 0.04). CONCLUSION: Our study provides evidence that miR-146a rs2910164 polymorphism may play an important role in susceptibility to CRC in Chinese male population.

An insertion/deletion polymorphism within the promoter of EGLN2 is associated with susceptibility to colorectal cancer.

OBJECTIVE: To investigate the association between susceptibility to colorectal cancer (CRC) and a 4-bp insertion/deletion polymorphism (rs10680577) in the proximal promoter of the EGLN2 gene. METHOD: The first step in genotyping EGLN2 was PCR, then the PCR products were separated using 7% nondenaturing polyacrylamide gel electrophoresis and visualized by silver staining according to the final product band location and quantity to determine the genotype of the sample. The final count was done by two different pathologists. RESULT: In the codominant model, compared with the ins/ins genotype, subjects with the heterozygous ins/del or homozygous del/del genotype had a significantly increased risk of CRC (adjusted OR = 1.45, p<0.0001 and OR = 2.44, p = 0.0001, respectively). Each additional copy of the 4-bp deletion allele conferred a significantly increased risk of CRC (OR = 1.47, 95% CI 1.28-1.66, p<0.0001). In the stratification analysis, we further proved that the association was more prominent in TNM stage III and IV cancer compared with stage I and II (adjusted OR = 1.43, 95% CI 1.07-1.93, p for heterogeneity = 0.02). CONCLUSIONS: Our study provided initial evidence that the insertion/deletion polymorphism rs10680577 may play a functional role in the development of CRC in the Chinese population.

Functional STR within PTPN11: a novel potential risk factor for colorectal cancer.

PTPN11 was previously regarded as a proto-oncogene, but recent reports have found that it acts as a tumor repressor in hepatocellular carcinogenesis and a prognostic predictor for colorectal carcinoma (CRC), although, its role in colorectal carcinogenesis is still unclear. This hospital-based case-control study with 830 CRC cases and 878 controls was carried out to determine the effect of the short tandem repeat (STR) polymorphism, located in the 3'UTR, on CRC risk in the study population of Chinese adults. Distribution of the genotypic frequency between CRC cases and controls in the Xuzhou study center revealed that the risk of CRC decreased as the repeat numbers increased. Compared with the 11/12 genotype, those with the 13/14 genotype were conferred reduced risk of CRC (OR=0.74, 95% CI=0.59-0.95, P=0.02), while carriers with the 15/16 genotype showed a marked reduction in CRC risk (OR=0.50, 95% CI=0.34-0.74, P=0.0004). A similar trend in genotype and allelic frequency was also observed in the Suining study center as well as in the pooled results. Using RT-qPCR analysis, longer alleles were found to upregulate the expression of PTPN11 in both tumor tissues and adjacent non-tumor tissues, with the expression of PTPN11 in non-CRC tissues observed to be 2.5-fold higher than those of CRC tissues. In the gain-of-function in vitro studies, it was found that constructs with allele 14 had the highest luciferase expression, while the allele 12 constructs had much lower expression, indicating that the STR polymorphism could influence the transcriptional activity and therefore was able to modulate PTPN11 expression. In conclusion, these findings indicate that the STR polymorphism located in PTPN11 modulates colorectal carcinogenesis probably through a motif change in the 3'UTR. Further studies with more study centers and the inclusion of other ethnic Chinese populations would have to be carried in the future so as to substantiate this observation.

A Polymorphism Within the 3'UTR of NLRP3 is Associated with Susceptibility for Ischemic Stroke in Chinese Population.

Stroke was regarded as a severe disorder with high morbidity and high mortality worldwide, ischemic stroke (IS) accounts for 85 to 90 % of new increased stroke cases. Partial mechanisms were elucidated by genetic factors including genomic instability such as single nucleotide polymorphism (SNP). Previous reports demonstrated that inflammation was involved in IS, NLRP3 [nucleotide-binding domain (NOD)-like receptor protein 3], acting as a specific inflammatory gene, however, its function and influence on IS was not well clarified. In this study, a case-control study including 1102 IS patients and 1610 healthy controls was conducted to investigate the association between IS susceptibility with a SNP (rs10754558) in 3'UTR of NLRP3. Logistic regression analysis showed that the heterozygote and the homozygote GG confer a significantly increased risk of CRC after controlling for other covariates (adjusted OR = 1.52, 95 % C.I. 1.19-1.97, P = 0.002; adjusted OR = 2.22, 95 % C.I. 2.18-3.67, P < 0.001, respectively). Carriage of G allele was associated with a greatly increased risk of developing the disease (OR = 1.69, 95 % C.I. 1.31-1.83, P < 0.001). Stratification analysis found that hypertension had interaction with rs10754558 to modulate IS risk. Further in vitro assay revealed that rs10754558 can affect mRNA level of NLRP3, suggesting its possible functional significance. Our data suggested that genetic polymorphisms in NLRP3 may influence IS risk in Chinese population. Replication of our studies in other populations and further functional studies are required for complete comprehension of the roles of NLRP3 polymorphisms in IS risk.

Pri-miR-124 rs531564 polymorphism and colorectal cancer risk.

MiR-124 functions as a tumor suppressor and plays an important role in tumorigenesis. A common polymorphism (rs531564, C>G) in the pri-miR-124 has been recently studied in connection with cancer risk. The aim of the present study was to investigate the association between pri-miR-124 rs531564 polymorphism and the risk and clinicopathological characteristics of colorectal cancer (CRC). Two case-control studies involving 900 CRC patients and 1110 cancer-free controls showed that pri-miR-124 rs531564 polymorphism was significantly associated with the decreased risk of CRC in Xuzhou population [GG vs. CC: OR = 0.25, 95%CI = 0.09-0.67, P = 0.003; (CG+GG) vs. CC: OR = 0.73, 95%CI = 0.56-0.94, P = 0.01; GG vs. (CC+CG): OR = 0.27, 95%CI = 0.10-0.70, P = 0.004; G vs. C: OR = 0.70, 95%CI = 0.56-0.89, P = 0.003], Bengbu population [GG vs. CC: OR = 0.20, 95%CI = 0.04-0.90, P = 0.02; GG vs. (CC+CG): OR = 0.21, 95%CI = 0.05-0.95, P = 0.03; G vs. C: OR = 0.72, 95%CI = 0.54-0.98, P = 0.03] and pooled population [GG vs. CC: OR = 0.26, 95%CI = 0.11-0.59, P<0.001; (CG+GG) vs. CC: OR = 0.76, 95%CI = 0.62-0.93, P = 0.008; GG vs. (CC+CG): OR = 0.27, 95%CI = 0.12-0.62, P < 0.001; G vs. C: OR = 0.71, 95%CI = 0.59-0.85, P<0.001]. Additionally, pri-miR-124 rs531564 polymorphism was significantly associated with the decreased risk of poor differentiation and lymph node metastasis of CRC. Our results suggest that pri-miR-124 rs531564 polymorphism may be a genetic modifier for developing CRC. However, further studies are needed to validate our findings.

Lysyl oxidase rs1800449 polymorphism and cancer risk among Asians: evidence from a meta-analysis and a case-control study of colorectal cancer.

Growing evidence has indicated that lysyl oxidase (LOX) G473A polymorphism (rs1800449) is associated with cancer risk among Asians. However, results of single center and small sample study lack enough power. We first investigated the effect of LOX G473A polymorphism on cancer risk among Asians by a meta-analysis, and then further validated this association by a case-control study of colorectal cancer (CRC) with LOX G473A polymorphism in a Chinese population. STATA 12.0 software was used for the meta-analysis. The relationships were evaluated by calculating the pooled odds ratios (ORs) and their 95 % confidence intervals (CIs). In a case-control study comprising 577 CRC patients and 696 controls, LOX G473A polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Logistic regression was used to evaluate genetic associations with the occurrence of CRC. The results of our meta-analysis, including seven case-control studies with a total of 2,377 cancer patients and 2,499 controls, suggested that LOX G473A polymorphism might be associated with an increased risk of cancer among Asians. In addition, results of a case-control study indicated that individuals with the AA or AG genotype had a significantly increased susceptibility to CRC occurrence, compared with individuals who had GG genotype. Overall, this meta-analysis and case-control study of CRC observed convincing association of LOX G473A polymorphism with cancer risk in Asians; our study would contribute to complete elucidation of carcinogenesis.

Genetic variation of ErbB4 confers risk of colorectal cancer in a Chinese Han population.

BACKGROUND: Colorectal cancer (CRC) is the most common cancer worldwide. Both genetic and environmental factors play an important role in pathogenesis of CRC, susceptibility may be modified by functional polymorphisms in receptor tyrosine kinase genes, such as ErbB4. We here evaluated whether a 12-bp insertion/deletion (indel) polymorphism (rs6147150) in the 3'UTR of ErbB4 could potentially affect the occurrence of CRC in Chinese population. METHODS: We studied the genotypic and allelic frequencies of ErbB4 polymorphism in 399 patients with CRC and 419 control participants using polymerase chain reaction and polyacrylamide gel electrophoresis method. RESULTS: Under co-dominant model, we found that the del/del genotype of indel was associated with a significantly increased risk of CRC compared with its homozygote ins/ins (adjusted OR=1.70, 95%CI=1.06-2.71). Under recessive model, carrying of del/del genotype conferred a significantly increased risk for CRC compared with ins/ins and ins/del genotype (adjusted OR=1.60, 95%CI=1.03-2.50). Presence of 12-bp deletion allele of ErbB4 seemed to confer higher risk for CRC when compared with non-carriers (adjusted OR=1.27, 95%CI=1.02-1.57). Further stratification analysis showed that this association was more pronounced in patients with drinking. CONCLUSION: Our data suggested that individuals in Chinese population with the ErbB4 12-bp deletion allele may be at higher risk for CRC, rs6147150 would potentially be a promising novel biomarker for CRC susceptibility. Further validation of our results in larger populations and studies with functional assays are required.

Non-association of IL-16 rs4778889 T/C polymorphism with cancer risk in Asians: a meta-analysis.

The IL-16 rs4778889 T/C polymorphism is associated with cancer risk. However, the results are conflicting. We performed this meta-analysis to derive a more precise estimation of the relationship. A comprehensive literature search was performed using PubMed, Embase and Web of Science databases. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of association. A total of 6 studies including 1,603 cases and 2,342 controls were identified. With all studies involved, results showed no statistically significant association between IL-16 rs4778889 T/C polymorphism and cancer risk (CC vs. CT+TT: OR=0.74, 95%CI: 0.55-1.02, Ph=0.15; CC+CT vs. TT: OR=0.89, 95%CI: 0.72-1.10, Ph =0.03; CC vs. TT: OR=0.73, 95%CI: 0.53- 1.00, Ph =0.08; CT vs. TT: OR=0.91, 95%CI: 0.79-1.05, Ph =0.08; C vs. T: OR=0.89, 95%CI: 0.74-1.07, Ph =0.02). In addition, the results were not changed when studies were stratified by cancer type. However, to verify our findings, it is essential to perform more well-designed studies with larger sample sizes in the future.

Insertion/deletion polymorphisms in the promoter region of BRM contribute to risk of hepatocellular carcinoma in Chinese populations.

BACKGROUND: BRM (Brahma homologue) is well known for its critical role in tumor suppression and cancer development. Genetic variations in the promoter region of BRM have been suggested to be associated with loss of BRM expression and lung cancer risk. To the authors' knowledge, no study on the role of BRM genetic polymorphisms in hepatocellular carcinoma (HCC) risk has been performed. METHODOLOGY/PRINCIPAL FINDINGS: In two independent case-control studies containing 796 HCC cases and 806 cancer-free individuals, we genotyped two putative functional insertion/deletion (indel) polymorphisms [BRM-1321 (rs3832613) and BRM-741 (rs34480940)] within promoter region of BRM in Chinese populations using a PCR-based method. Real-time RT-PCR analysis was used to explore the genotype-phenotype correlation between these polymorphisms and BRM expression in both tissue samples and HCC cell lines. Logistic regression analysis showed that compared to BRM-1321del/del genotype, the ins/del and ins/ins variant genotypes had an increased HCC risk [adjusted odds ratio (OR) = 1.47, 95% confidence interval (CI) = 1.19-1.82; adjusted OR = 2.55, 95% CI = 1.75-3.72, respectively]. No significant association between BRM-741 and HCC incidence was observed. However, stratification analysis revealed a significant association between ins/ins genotype of BRM-741 and increased HCC susceptibility in smokers (adjusted OR = 2.07, 95% CI = 1.33-3.22). Quantitative PCR analyses demonstrated that the genotypes of BRM-1321 and the corresponding haplotypes were significantly correlated with BRM expression in vivo. Compared with ins/ins genotype, subjects carrying ins/del and del/del genotype had 2.30 and 4.99 fold higher BRM expression in HCC tissue samples, respectively. Similar trends were observed in western blot analysis at protein level. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that BRM promoter polymorphism (BRM-1321) could regulate BRM expression and may serve as a potential marker for genetic susceptibility to HCC.

S100+ cells: a new neuro-immune cross-talkers in lymph organs.

Up to now, the 'hardwired' neural pathway of the neuro-immune regulation is not fully understood. Here we reported a new neural pathway which links sympathetic nerves with immune cells of the lymphoid tissues. Our results demonstrated that nerve fibers derived from superior cervical ganglion directly targeted only S100(+) cells in the cervical lymph nodes. Moreover, we found co-expression of neurotransmitters such as norepinephrine, vasoactive intestinal polypeptide and neuropeptide Y in the postganglionic sympathetic nerve endings that innervate S100(+) cells. Our findings suggested that S100(+) cells serve as a neuro-immune cross-talker in lymph organs that may play a significant role in transmitting signals of nervous cells to targeted immune cells. The new findings provide better understanding of the cross-talk mechanism between the nervous system and the immune system.

The adhesion and proliferation of bone marrow-derived mesenchymal stem cells promoted by nanoparticle surface.

This study's aim consists of evaluating the adhesion and proliferation of mesenchymal stem cells (MSCs) derived from rat bone marrow on nanoparticle Titanium (Ti) surface. Hence, passage 3 MSCs were, respectively, seeded on nanoparticle Ti and pure Ti surfaces and then cultured for 32 h. Cell morphology and viability were separately examined by scanning electron microscopy and 3-(4,5-dimethylthiazsol-2-yl)-2,5-diphenyltetrazolium bromide assay. Moreover, the mitotic rate of the attached MSCs was observed through immunocytochemistry. The real-time polymerase chain reaction was applied to determine the adhesion-associated messenger ribonucleic acid (mRNA), CD44 gene encoding variant isoform 6 (CD44 V6), and the integrinß1 level. The results showed that MSCs performed better in faster extension on the nanoparticle Ti surface than on the pure Ti surface after culturing for 4 h, and were quicker in fusion patterns after 16 h. Furthermore, cell viability was significantly increased on the nanoparticle Ti surface compared to that of the pure Ti surface 16 h after initial seeding (p < 0.05), and the mitotic rate of attached MSCs on the nanoparticle Ti surface was higher than that on the pure Ti surface after 32 h (p < 0.05). More interestingly, the CD44 V6 and integrinß1 mRNA in the nanoparticle Ti surface group expressed higher than that in the pure Ti surface group after 4 h (p < 0.05), and positive correlation between CD44 V6 and integrinß1 was found through statistical analysis (correlation coefficient r (s) = 0.98, p < 0.05). Our study's result indicates that a nanoparticle Ti surface can significantly promote the adhesion and proliferation of MSCs, and also improve the bioactivity of Ti surface.

Association between PTEN IVS4 polymorphism and cancer risk: a meta-analysis.

BACKGROUND: PTEN, a candidate tumor suppressor gene, has been identified within chromosome 10q23 and plays an important role in tumorigenesis. The association between the IVS4 insertion/deletion (I/D) polymorphism of PTEN and cancer risk in several populations has been studied, but results are conflicting. The aim of the present study was to investigate association of PTEN IVS4 polymorphism with cancer risk by conducting a meta-analysis. METHODS: A literature search was conducted through PubMed, Chinese National Knowledge Infrastructure (CNKI) and WanFang databases (up to October 18, 2013). Six eligible studies with 2,179 cases and 3,132 controls were enrolled in the meta-analysis. The pooled odds ratio (OR) and 95% confidence intervals (CI) were used to assess the strength of association. RESULTS: Our results indicated that the~polymorphism conferred a significantly decreased risk of overall cancer (dominant model: OR=0.87, 95% CI 0.77-0.99; recessive model: OR=0.83, 95% CI: 0.72-0.96; II vs. DD model: OR=0.79, 95% CI: 0.67-0.94; I vs. D model: OR=0.89, 95% CI: 0.82-0.97). Subgroup analysis by cancer type and ethnicity furtherly showed that PTEN gene IVS4 polymorphism was associated with decreased risk of digestive cancers (recessive model: OR=0.77, 95% CI: 0.64-0.92; II vs. DD model: OR=0.72, 95% CI: 0.58-0.91; I vs. D model: OR=0.84, 95% CI: 0.76-0.94), this strong association with reduced risk of cancer was also found in Asian population (recessive model: OR=0.83, 95% CI: 0.71-0.98; II vs. DD model: OR=0.79, 95% CI: 0.65-0.96; I vs. D model: OR=0.89, 95% CI: 0.81-0.98). CONCLUSION: In conclusion, our meta-analysis suggested that PTEN IVS4 polymorphism might play a protective role in the development of cancer, further independent confirmation of associations observed in PTEN IVS4 polymorphism by more studies was necessary.

An insertion/deletion polymorphism within RERT-lncRNA modulates hepatocellular carcinoma risk.

The Prolyl hydroxylase 1 (EGLN2) is known to affect tumorigenesis by regulating the degradation of hypoxia-inducible factor. Polymorphisms in EGLN2 may facilitate cancer cell survival under hypoxic conditions and directly associate with cancer susceptibility. Here, we examined the contribution of a 4-bp insertion/deletion polymorphism (rs10680577) within the distal promoter of EGLN2 to the risk of hepatocelluar carcinoma (HCC) in Chinese populations. The contribution of rs10680577 to HCC risk was investigated in 623 HCC cases and 1,242 controls and replicated in an independent case-control study consisting of 444 HCC cases and 450 controls. Logistic regression analysis showed that the deletion allele of rs10680577 was significantly associated with increased risk for HCC occurrence in both case-control studies [OR = 1.40; 95% confidence interval (CI) = 1.18-1.66, P < 0.0001; OR = 1.49; 95% CI = 1.18-1.88, P = 0.0007]. Such positive association was more pronounced in current smokers (OR = 3.49, 95% CI = 2.24-5.45) than nonsmokers (OR = 1.24, 95% CI = 1.03-1.50; heterogeneity P = 0.0002). Genotype-phenotype correlation studies showed that the deletion allele was significantly correlated with higher expression of both EGLN2 and RERT-lncRNA [a long noncoding RNA whose sequence overlaps with Ras-related GTP-binding protein 4b (RAB4B) and EGLN2)] in vivo and in vitro. Furthermore, RERT-lncRNA expression was also significantly correlated with EGLN2 expression in vivo, consistent with in vitro gain-of-function study that showed overexpressing RERT-lncRNA upregulated EGLN2. Finally, in silico prediction suggested that the insertion allele could disrupt the structure of RERT-lncRNA. Taken together, our findings provided strong evidence for the hypothesis that rs10680577 contributes to hepatocarcinogenesis, possibly by affecting RERT-lncRNA structure and subsequently EGLN2 expression, making it a promising biomarker for early diagnosis of HCC.

A functional insertion/deletion polymorphism in the proximal promoter of CD3G is associated with susceptibility for hepatocellular carcinoma in Chinese population.

Hepatocellular carcinoma (HCC) represents the most common primary malignancy of the liver with a worldwide increasing incidence. Although the risk factors for HCC are well characterized, the molecular mechanisms responsible for malignant transformation of hepatocytes are not well understood. In this study, a case-control study including 291 HCC patients and 294 healthy controls was conducted to investigate the association between HCC susceptibility and with a 4-bp insertion/deletion polymorphism (rs66465034) in the proximal promoter of CD3G. Logistic regression analysis showed that the heterozygote and the homozygote 4-bp ins/ins confer a significantly increased risk of HCC after controlling for other covariates (adjusted odds ratio [OR]=1.51, 95% confidence interval [C.I.] 1.01-2.27, p=0.040; OR=1.71, 95% C.I. 1.07-2.89, p=0.025, respectively). Carriage of the 4-bp insertion allele was associated with a greatly increased risk of developing the disease (OR=1.30, 95% C.I. 1.02-1.64, p=0.027). Moreover, hepatitis B virus (HBV) stratification analysis showed that the differences between cases and controls were more obvious in HBV-positive than in the HBV-negative population, suggesting a possible role of this polymorphism in the immune regulation during HBV infection. Further, luciferase-based transient transfection assays revealed that rs66465034 can affect promoter activity of CD3G, indicating its possible functional significance. Our data suggested that common genetic polymorphisms in CD3G may influence HCC risk in Chinese population. Considering the relative small sample size, replication in other populations with larger sample size and further functional analysis are required for fully understanding the roles of CD3G polymorphisms in predisposition for HCC.

A 40-bp insertion/deletion polymorphism in the constitutive promoter of MDM2 confers risk for hepatocellular carcinoma in a Chinese population.

The pathogenesis of HCC is a multistage process with the involvement of genetic factors. The aim of the present study is to investigate the possible association between a 40-bp insertion/deletion polymorphism (indel) at constitutive promoter of MDM2 and risk of hepatocellular carcinoma (HCC) in a Chinese population. Using 420 HCC patients and 423 control subjects, we genotyped the indel polymorphism (rs3730485) using polymerase chain reaction method. Logistic regression was used to analyze the association between the polymorphism and HCC susceptibility. Under co-dominant model, we found that the ins/del and del/del genotype of indel was associated with a significantly increased risk of HCC compared with its homozygote ins/ins (OR=1.39, 95%C.I.=1.03-1.87; OR=1.68, 95%C.I.=1.03-2.73, respectively). Presence of 40-bp deletion allele of MDM2 seemed to confer higher risk for HCC when compared with non-carriers (OR=1.30, 95%C.I.=1.06-1.60, P=0.011). Further stratification analysis showed that this association was more pronounced in patients with a family history of HCC, early tumor stage and higher serum alpha-fetoprotein (AFP). These findings indicated that the MDM2 indel polymorphism may be a genetic modifier for developing HCC in Chinese population.

An insertion/deletion polymorphism in the 3' untranslated region of type I collagen a2 (COL1A2) is associated with susceptibility for hepatocellular carcinoma in a Chinese population.

Hepatocellular carcinoma (HCC) is one of the most common and severe diseases in the world. Besides the influence of environmental factors, such as viral infection, an increasing number of novel genetic components identified by genome-wide association studies have been associated with predisposition to HCC. Thus, studies focusing on functional variants in these findings are indispensable. In the present study, based on in-silico analysis, we carried out a case-control study in a Chinese population (207 cases and 245 controls) to investigate the association between HCC susceptibility with a 7 base pair (bp) insertion/deletion polymorphism (rs3917) in the 3'UTR of COL1A2. Our results showed that the ins/del + del/del genotype had an odds ratio of 1.76 (95% C.I.=1.03-3.01; P=0.028) for developing HCC compared to the ins/ins genotype. Carriers for the "del" allele of rs3917 were associated with a 1.73-fold increased risk for HCC (95% C.I.=1.06-2.84; P(trend)=0.02). Computational modeling suggests that this polymorphism is located in the hsa-let-7 g potential target sequence in the COL1A2 3' untranslated region. Our data suggest that most likely, common genetic changes in COL1A2 may influence HCC risk, at least in part by let-7 g-mediated regulation, which is possibly involved in the pathogenesis of HCC. The replication of our studies in other populations will further strengthen our understanding of this association.