The predictive potential of genetic single nucleotide polymorphisms in CBX4 for hepatocellular carcinoma survival

Background: Our previous studies have reported that polycomb chromobox 4 (CBX4) has a potential promoting hepatocellular carcinoma (HCC) angiogenesis and tumor progression. However, it is unclear whether genetic single-nucleotide polymorphisms (SNPs) in this gene are associated with HCC prognosis. Methods: We conducted a hospital-based two-phase study, including 598 patients with pathologically diagnosed HCC for the SNPs screening phase and 328 HCC patients for clinic significance validating phase, to elucidate the association between SNPs of CBX4 and the survival of HCC. The genotypes of CBX4 were tested using the SNaPshot method and the effects of CBX4 SNPs on HCC prognosis were analyzed using Kaplan-Meier survival model and Cox regression model. Results: A total of 33 SNPs were selected and genotyped in this study. We found the rs77447679 SNP was significantly related to survival in individuals with HCC. Specifically, survival was noticeably decreased in HCC patients who have mutant homozygote AA of this SNP (rs77447679-AA) compared with these with wild type (rs77447679-CC). An additive effect of rs77447679 polymorphism and aflatoxin B1 exposure level was also observed in the survival analyses of HCC cases. Furthermore, this SNP was positively correlated not only with tumor size, grade, stage, and microvessel density (correlation coefficient r = 0.17, 0.23, 0.23, and 0.42, respectively), but also with increasing CBX4 expression (r = 0.57). Interestingly, the mutant genotypes of rs77447679 can significantly improve the therapeutic response of HCC cases on post-operative adjuvant transarterial chemoembolization (pa-TACE), but wild type not. Conclusions: These data suggest that genetic polymorphisms in the CBX4 may be a prognostic biomarker for HCC, and the rs77447679 SNP is such a potential candidate.

Single-nucleotide polymorphisms in the coding region of a disintegrin and metalloproteinase with thrombospondin motifs 4 and hepatocellular carcinoma: A retrospective case-control study

Previous studies have shown that single-nucleotide polymorphisms (SNPs) of a disintegrin and metalloproteinase with thrombospondin type 1 motif 4 (ADAMTS4) may involve in the pathogenesis of some diseases. However, it is not clear whether they are associated with hepatocellular carcinoma (HCC). A hospital-based case-control study, including 862 cases with HCC and 1120 controls, was conducted to assess the effects of 258 SNPs in the coding regions of ADAMTS4 on HCC risk and prognosis. We found that six SNPs in ADAMTS4 were differential distribution between cases and controls via the primary screening analyses; however, only rs538321148 and rs1014509103 polymorphisms were further identified to modify the risk of HCC (odds ratio: 2.73 and 2.95; 95% confidence interval, 2.28-3.29 and 2.43-3.58; P-value, 5.73 × 10^-27 and 1.36 × 10^-27 , respectively). Significant interaction between these two SNPs and two known causes of hepatitis B virus and aflatoxin B1 were also observed. Furthermore, rs538321148 and rs1014509103 polymorphisms were associated not only with clinicopathological features of tumor such as tumor stage and grade, microvessel density, and vessel metastasis, but with poor overall survival. Additionally, these SNPs significantly downregulated ADATMS4 expression in tumor tissues. These data suggest that SNPs in the coding region of ADAMTS4, such as rs538321148 and rs1014509103, may be potential biomarkers for predicting HCC risk and prognosis.

Micro RNA-4651 Serves as a Potential Biomarker for Prognosis When Selecting Hepatocellular Carcinoma Patients for Postoperative Adjuvant Transarterial Chemoembolization Therapy

Our previous reports have shown that microRNA-4651 is a potential early diagnostic and prognostic marker for hepatocellular carcinoma. We aimed to investigate whether microRNA-4651 modified postoperative adjuvant transarterial chemoembolization (pa-TACE) to improve the prognosis of hepatocellular carcinoma. A hospital-based retrospective study, including 302 patients with advanced-stage hepatocellular carcinoma who received tumor resection or tumor resection plus pa-TACE as an initial therapy, was conducted to assess the effects of microRNA-4651 on pa-TACE treatment. MicroRNA-4651 expression in tumor tissues was tested using the TaqMan-PCR technique. The sensitivity of tumor cells to doxorubicin (an anticancer drug used in pa-TACE procedure) was analyzed by the half-maximal inhibitory concentration (IC50). Upregulated microRNA-4651 expression in tumor tissues can improve the therapeutic response of patients with hepatocellular carcinoma on pa-TACE (hazard ratios [95% confidence intervals] = 0.32 [0.22-0.46] for death risk and 0.39 [0.28-0.56] for tumor-recurrence risk, respectively), but downregulated expression cannot. Functional analyses-displayed microRNA-4651 mimics decreased while its inhibitor increased the IC50 of tumor cells to doxorubicin (0.65 [0.61-0.69] versus 2.17 [1.98-2.37] µM). Cytochrome P450 2W1 was shown as a possible target of microRNA-4651. Additionally, dysregulation of microRNA-4651 also affected the clinical pathological features of hepatocellular carcinoma and was an independent prognostic factor for this cancer. Conclusion: These results indicate that increasing microRNA-4651 expression may be beneficial for pa-TACE in improving hepatocellular carcinoma prognosis.

Genetic polymorphisms in ataxin-3 and liver cirrhosis risk related to aflatoxin B1

Background

Altered expression of ataxin-3 (AT3) can modify DNA repair capacity and is observed in human diseases. The genetic polymorphisms of this gene in aflatoxin B1 (AFB1)–related liver cirrhosis (LC) have not yet been elucidated.

Materials and Methods

We conducted a hospital-based case–control study, including 384 patients with LC and 851 controls without any liver diseases, to assess the association between 264 polymorphisms in AT3 and AFB1-related LC risk. Genotype were tested using TaqMan-PCR or sequencing technique.

Results

We found three differentially distributed SNPs (rs8021276, rs7158733, and rs10146249) via the screening analysis; however, only rs8021276 polymorphism was further identified to modify the risk of LC. Compared with the homozygote of rs8021276 A alleles (rs8021276-AA), the genotypes of rs8021276 G alleles (rs8021276-AG or -GG) increased LC risk (OR: 2.48 and 6.98; 95% CI: 1.84–3.33 and 4.35–11.22, respectively). Significant interactive effects between risk genotypes and AFB1 exposure status were also observed in the joint effects analysis. Additionally, rs8021276 polymorphism was also associated with down-regulation of AT3 mRNA expression and increasing AFB1-DNA adducts in liver tissues with cirrhosis.

Conclusions

These results suggest AT3 polymorphisms may be risk biomarkers of AFB1-related LC, and rs8021276 is a potential candidate.

Diagnostic and prognostic potential of serum microRNA-4651 for patients with hepatocellular carcinoma related to aflatoxin B1

Background

The serum microRNAs have been reported as potential biomarkers for hepatitis virus-related hepatocellular carcinoma (HCC); however, their role in aflatoxin B1 (AFB1)-related HCC to has not yet been evaluated.

Materials and Methods

We conducted a case-control study, including 366 HCC cases and 662 controls without any evidence of tumors, to identify and assess diagnostic and prognostic potential of serum microRNAs for AFB1-related HCC. The sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were used to elucidate diagnostic performance, and to compare the microRNAs with α-fetoprotein (AFP) at a cutoff of 20 ng/mL (AFP20) and 400 ng/mL (AFP400).

Results

We found 8 differentially expressed microRNAs via the microRNA array analysis; however, only microRNA-4651 was further identified to detect AFB1-positive HCC but not AFB1-negative HCC. For AFB1-positive HCC, microRNA-4651 showed higher accuracy and sensitivity than AFP400 (AUC, 0.85 vs. 0.72; Sensitivity, 78.1% vs. 43.0%). Compared to AFP20, microRNA-4651 exhibited higher potential in identifying small-size (0.68 vs. 0.84 for AUC and 36.7% vs. 75.5% for sensitivity, respectively) and early-stage HCC (0.69 vs. 0.84 for AUC and 38.7% vs. 75.7% for sensitivity, respectively). Additionally, miR-4651 was also associated with HCC prognosis (hazard risk value, 2.67 for overall survival and 3.62 for tumor recurrence analysis).

Conclusions

These data suggest that serum microRNA-4651 may be a useful marker for HCC diagnosis and prognosis, especially AFB1-positive cases.

Prognostic significance of miR-1268a expression and its beneficial effects for post-operative adjuvant transarterial chemoembolization in hepatocellular carcinoma

Our recent investigation has shown that the variables of microRNA-1268a may involve in hepatocellular carcinoma (HCC) tumorigenesis. Here, we attempted to identify the prognostic significance of microRNA-1268a expression in tumor tissues by a retrospective analysis in 411 patients with HCC, and analyze its effects on post-operative adjuvant transarterial chemoembolization (TACE) improving HCC prognosis. All cases received tumor resection or tumor resection plus post-operative adjuvant TACE as an initial treatment. Logistical regression analysis exhibited that microRNA-1268a expression was significantly correlated with tumor stage, tumor grade, tumor size, and microvessel density. Cox regression analysis showed that microRNA-1268a expression was an independent prognostic factor for HCC, and TACE treatment had no effects on prognosis of HCC patients with high microRNA-1268a expression. More intriguingly, TACE improved the prognosis of HCC patients with low microRNA-1268a expression. Functionally, overexpression of microRNA-1268a inhibited while its inhibitor enhanced doxorubicin-induced the death of cancer cells. These results suggest that microRNA-1268a may be an independent prognostic factor for HCC patients, and that decreasing microRNA-1268a expression may be beneficial for post-operative adjuvant TACE treatment in HCC.

Spautin-1 Ameliorates Acute Pancreatitis via Inhibiting Impaired Autophagy and Alleviating Calcium Overload

Acute pancreatitis is characterized by zymogen pre-activation. Severe inflammation caused by zymogen activation can eventually lead to multiple organ dysfunctions, which contributes to the high mortality rate of severe acute pancreatitis. However, there is no specific treatment available for acute pancreatitis therapy. Here, we show that spautin-1, which effectively inhibits autophagy flux, ameliorated the pathogenesis of acute pancreatitis induced by cerulein or L-Arginine. CaMKII phosphorylation due to cytosolic calcium oeverload was revealed in this paper. It was also demonstrated that autophagic protein aggregates degradation blockade accompanying with impaired autophagy correlated positively to intra acinar cells digestive aymogen activation sitimulated by cerulein or L-Arginine. The role of spautin-1 in ameliorating acute pancreatitis was shown here to be associated with impaired autophagy inhibition and Ca²⁺ overload alleviation. We provided a promising therapy for acute pancreatitis here through targeting both impaired autophagy and increased cytosolic calcium.

Glycogen metabolic reprogramming in hepatocellular carcinoma: An update

Hepatocellular carcinoma (HCC) is a highly prevalent malignant tumor. Abnormal glycogen metabolism, an important metabolism process in HCC, mainly results from the variant structure, function, and expression levels of the corresponding enzymes and proteins. This variation, also called metabolic reprogramming, can regulate glycogen metabolic pathway to promote HCC tumorigenesis. This review aims to summarize glycogen metabolism-regulated factors (including glucose transporters, glycogen synthase kinase 3β, and glycogen phosphorylase) involved in glycogen metabolic reprogramming in HCC

CD4+CD25+ cells in multiple myeloma related renal impairment

CD4⁺CD25⁺ cells are critical regulators in almost all of the animal models of human organ-specific autoimmune diseases, transplant rejection and allergic diseases. We aimed to explore the role of CD4⁺CD25⁺ cells in the pathogenesis of multiple myeloma (MM) related renal impairment (RI). Thirty patients with MM related RI and 30 healthy volunteers were studied. The number of CD4⁺CD25⁺ cells was examined by flow cytometry. Clinical and laboratory data were collected from each subject. Glomerular injury was assessed by histopathology. Serum IL-2, IL-4 and IL-6 were analyzed by ELISA. CD4⁺CD25⁺ cells significantly decreased in MM related RI patients compared to the controls (P<0.05). CD4⁺CD25⁺ cell number was negatively associated with blood urea nitrogen (BUN), supernatant IL-4, serum IL-6, monoclonal immunoglobulin and β2-microglobulin, as well as bone marrow plasma cell percentage and proteinuria; whereas positively associated with estimated glomerular filtration rate (eGFR) (all P < 0.05). CD4⁺CD25⁺ cells gradually decreased as the Clinic Stage increased. The number of CD4⁺CD25⁺ cells reduced in MM related RI patients, and was correlated with disease severity. CD4⁺CD25⁺ cells may play an important role in the pathogenesis of MM related RI.

Polymorphisms in the precursor microRNAs and aflatoxin B1-related hepatocellular carcinoma

The altered expression of some microRNAs (miRNAs) is observed in hepatocellular carcinoma (HCC); however, the genetic polymorphisms in the precursor miRNAs (pre-miRNAs) in aflatoxin B1 (AFB1)-related HCC have not yet been investigated. A hospital-based case-control study, including 1,706 HCC cases and 2,270 controls without any liver diseases or tumors, was conducted in a high AFB1 exposure area of China to assess the relationship between 48 polymorphisms in the pre-miRNAs and AFB1-related HCC risk and prognosis. Among 48 polymorphisms, only rs28599926 (in the miRNA 1268a) affected HCC risk. Compared with the homozygote of rs28599926C alleles (rs28599926-CC), the genotypes of rs28599926 T alleles (namely rs28599926-CT or -TT) increased HCC risk (odds ratio [OR]: 1.63 and 5.52, 95% confidence interval [CI]: 1.40-1.90 and 4.27-7.14, respectively). Significant interactive effects between risk genotypes and AFB1 exposure status were also observed in the joint effects analysis. This polymorphism was associated not only with larger tumor size, higher portal vein tumor risk, and tumor dedifferentiation, but also with higher AFB1 adducts levels and increasing the mutation risk of TP53 gene. Furthermore, rs28599926 modified the tumor recurrence-free survival (hazard ratio [HR]: 2.86, 95% CI: 2.36-3.43) and overall survival (HR: 2.12, 95% CI: 1.86-2.41) of cases. Additionally, one target of miR-1268a was show to be the ADAMTS4 mRNA and rs28599926 polymorphism might modify ADAMTS4 expression. These findings indicate that polymorphisms in the pre-miRNAs may be risk and prognostic biomarkers of AFB1-related HCC, and rs28599926 in miR-1268a is such a potential candidate. © 2015 Wiley Periodicals, Inc.

Genetic variants in five novel loci including CFB and CD40 predispose to chronic hepatitis B

Hepatitis B virus affects more than 2 billion people worldwide, 350 million of which have developed chronic hepatitis B (CHB). The genetic factors that confer CHB risk are still largely unknown. We sought to identify genetic variants for CHB susceptibility in the Chinese population. We undertook a genome-wide association study (GWAS) in 2,514 CHB cases and 1,130 normal controls from eastern China. We replicated 33 of the most promising signals and eight previously reported CHB risk loci through a two-stage validation totaling 6,600 CHB cases and 8,127 controls in four independent populations, of which two populations were recruited from eastern China, one from northern China and one from southern China. The joint analyses of 9,114 CHB cases and 9,257 controls revealed significant association of CHB risk with five novel loci. Four loci are located in the human leukocyte antigen (HLA) region at 6p21.3, including two nonsynonymous variants (rs12614 [R32W] in complement factor B [CFB], Pmeta =1.28 × 10(-34) ; and rs422951 [T320A] in NOTCH4, Pmeta  = 5.33 × 10(-16) ); one synonymous variant (rs378352 in HLA-DOA corresponding to HLA-DOA*010101, Pmeta  = 1.04 × 10(-23) ); and one noncoding variant (rs2853953 near HLA-C, Pmeta  = 5.06 × 10(-20) ). Another locus is located at 20q13.1 (rs1883832 in the Kozak sequence of CD40, Pmeta  = 2.95 × 10(-15) ). Additionally, we validated seven of eight previously reported CHB susceptibility loci (rs3130542 at HLA-C, rs1419881 at TCF19, rs652888 at EHMT2, rs2856718 at HLA-DQB1, rs7453920 at HLA-DQB2, rs3077 at HLA-DPA1, and rs9277535 at HLA-DPA2, which are all located in the HLA region, 9.84 × 10(-71)  ≤ Pmeta  ≤ 9.92 × 10(-7) ).

CONCLUSION

Our GWAS identified five novel susceptibility loci for CHB. These findings improve the understanding of CHB etiology and may provide new targets for prevention and treatment of this disease.

Metformin decreases IL-22 secretion to suppress tumor growth in an orthotopic mouse model of hepatocellular carcinoma

Epidemiological, preclinical and cellular studies in the last 5 years have shown that metformin exerts anti-tumoral properties, but its mode of action in cancer remains unclear. Here, we investigated the effects of metformin on a mouse hepatocellular carcinoma (HCC) model and tumor-associated T cell immune responses. Oral metformin administration led to a significant reduction of tumor growth, which was accompanied by decreased interleukin-22 (IL-22). Meanwhile, IL-22-induced STAT3 phosphorylation and upregulation of downstream genes Bcl-2 and cyclin D1 were inhibited by metformin. At the cellular level, metformin attenuated Th1- and Th17-derived IL-22 production. Furthermore, metformin inhibited de novo generation of Th1 and Th17 cells from naive CD4(+) cells. These observations were further supported by the fact that metformin treatment inhibited CD3/CD28-induced IFN-γ and IL-17A expression along with the transcription factors that drive their expression (T-bet [Th1] and ROR-γt [Th17], respectively). The effects of metformin on T cell differentiation were mediated by downregulated STAT3 and STAT4 phosphorylation via the AMP-activated kinase-mammalian target of rapamycin complex 1 pathway. Notably, metformin led to a reduction in glucose transporter Glut1 expression, resulting in less glucose uptake, which is critical to regulate CD4(+) T cell fate. Taken together, these findings provide evidence for the growth-inhibitory and immune-modulatory effects of metformin in HCC and thus, broaden our understanding about the action of metformin in liver cancer treatment.

A review of life quality in living donors after liver transplantation

Living-donor liver transplantation (LDLT) has increasingly performed all around the world. However, LDLT donors achieve no medical benefits and are exposed to the risk of complications, and even death. The potential effects of LDLT on donor safety, donor recovery, and post-donation psychological impairment are essential to be better understood. We searched the MEDLINE database to identify articles about the quality of life (QOL) in adults after LDLT donation. Twenty-eight studies with a total of 1944 donors were included in the review. 14 of the 28 studies (50%) had a cross-sectional design, and the remaining half had a prospective design. The Physical Component Score (PCS) decreased immediately after the donation, then returned to the baseline within 6 to 12 months while the Mental Component Score (MCS) remains comparable to that of normative population throughout the procedure. Compared with the left graft (LG) donors, right graft (RG) donors were significantly older, had longer hospital stays and higher rates of postoperative complications, and a higher recipient mortality rate, while there were no difference in the PCS and MCS between the two groups. Our review clearly indicates that the LDLT donors can endure the donation procedure and return to their normal daily life without major problem in the short term. However, to improve the donor selection criteria and ensure the QOL in donors throughout donation procedure, more studies with longer follow up and larger samples are essential and predictors of poor QOL should be identified in study with sufficient response rate and ideal control groups.

XPC codon 939 polymorphism is associated with susceptibility to DNA damage induced by aflatoxin B1 exposure

Aflatoxin B1 (AFB1), resulting in the formation of AFB1-DNA adducts, is a known human carcinogen. AFB1-exposure individuals with inherited susceptible carcinogen-repairing genotypes may experience an increased risk of genotoxicity. This study was aimed to investigate whether DNA repair gene xerodermapigmentosum complementation group C codon 939 polymorphism (rs2228001) affected the levels of AFB1-DNA adducts in Guangxi Population (n = 2558), from an AFB1-exposure area. AFB1-DNA adducts were measured by ELISA, and XPC codon 939 genotypes were identified by TaqMan-PCR. We found that longer AFB1-exposure years significantly increased XPC genotypes with codon 939 Gln alleles (namely, XPC-LG and -GG, odds ratios [95% confidence intervals] were 1.37 (1.15-1.63) and 1.99 (1.55-2.55), respectively) was significantly associated with higher levels of AFB1-DNA adducts. Furthermore, there was a positive joint effect between XPC genotypes and long-year AFB1 exposure in the formation of AFB1-DNA adducts. These results suggest that individuals with susceptible genotypes XPC-LG and -GG may experience an increased risk of DNA damage elicited by AFB1 exposure.

Progress in research of microRNA-24

MicroRNAs are endogenous, small, and noncoding RNAs of 18-24 nucleotides in length that regulate tissue/organ development, cell growth, differentiation, and apoptosis and play an essential role in the development and progression of tumors. This paper will discuss the biological characteristics of microRNA-24 and its biological role in tumors and non-tumor diseases, with an aim to provide new clues to disease diagnosis and treatment to reduce the mortality of patients.

CD(+)(4)CD(+)(25) Treg cells in thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus patients

AIM

CD(+)(4)CD(+)(25) Treg cells are of critical importance for maintenance of tolerance. The purpose of the this study was to observe the number of CD(+)(4)CD(+)(25) Treg cells in the patients with thrombotic thrombocytopenic purpura (TTP) associated with systemic lupus erythematosus (SLE), and to study pathogenesis of TTP with SLE.

METHODS

Seven patients with TTP associated with SLE and seven healthy volunteers were studied. The CD(+)(4)CD(+)(25) Treg cells were examined by flow cytometry. Clinical and laboratory data, such as urinary protein, serum creatinine, endothelial markers and immunologic serologics, were obtained from each patient and healthy volunteer. Glomerular injury was assessed by histopathology. Serum IL-2, IL-4, IL-6 and anti-endothelial cell antibody were analyzed by ELISA and anti-ADAMTS13 antibody were detected by Western blotting.

RESULTS

CD(+)(4)CD(+)(25) Treg cells significantly decreased in TTP with SLE patients compared with controls (p < 0.05). CD(+)(4)CD(+)(25) Treg cells are negatively correlated with blood urea nitrogen, serum uric acid, supernatant IL-4, and proteinuria, and positively with estimated glomerular filtration rate (eGFR) in TTP with SLE patients. [Formula: see text] Treg cells gradually decreased as the severity of renal histology increased. Serum IL-2, IL-6, supernatant IL-4, anti-endothelial cell antibody, and anti-ADAMTS13 antibody significantly increased in TTP with SLE patients compared to those of the control groups (all p < 0.05). In contrast, serum levels of C3 were significantly decreased in TTP with SLE patients compared to those of the control groups (p < 0.05).

CONCLUSIONS

CD(+)(4)CD(+)(25) Treg cells are not only lower in TTP with SLE patients, but also are correlated with disease severity in TTP with SLE patients.CD(+)(4)CD(+)(25)Treg cells may play an important role in the pathogenesis of TTP with SLE.

Cbx4 governs HIF-1α to potentiate angiogenesis of hepatocellular carcinoma by its SUMO E3 ligase activity

Cbx4 is a polycomb group protein that is also a SUMO E3 ligase, but its potential roles in tumorigenesis remain to be explored. Here, we report that Cbx4, but not other members of the Cbx family, enhances hypoxia-induced vascular endothelial growth factor (VEGF) expression and angiogenesis in hepatocellular carcinoma (HCC) cells through enhancing HIF-1α sumoylations at K391 and K477 in its two SUMO-interacting motifs-dependent mechanisms and increasing transcriptional activity of HIF-1. The Cbx4 expression is significantly correlated with VEGF expression, angiogenesis, and the overall survival of HCC patients and also in subcutaneously and orthotopically transplanted mice HCC models. Collectively, our findings demonstrate that Cbx4 plays a critical role in tumor angiogenesis by governing HIF-1α protein.

Polymorphisms in the coding region of X-ray repair complementing group 4 and aflatoxin B1-related hepatocellular carcinoma

X-ray repair complementing group 4 (XRCC4) is very important in maintaining overall genome stability and may play an important role in carcinogenesis. We aimed to investigate the role of polymorphisms in the coding region of this gene in hepatocellular carcinoma (HCC) caused by aflatoxin B1 (AFB1). A hospital-based case-control study, including 1,499 HCC cases and 2,045 controls without any liver diseases or tumors, was conducted in a high AFB1 exposure area (the Guangxi region) to assess the relationship between 21 polymorphisms in the coding region of XRCC4 and AFB1-related HCC risk and prognosis. Among these 21 polymorphisms, only rs28383151 modified HCC risk. These individuals with the genotypes of rs28383151 A alleles (rs28383151-GA/AA), compared with the homozygote of rs28383151 G alleles (rs28383151-GG), faced increasing risk of HCC (odds ratio [OR]: 2.17; 95% confidence interval: 1.77-2.67). Significant interactive effects between risk genotypes (OR, >1) and AFB1 exposure status were also observed in the joint-effects analysis. Furthermore, this polymorphism was correlated not only with lower XRCC4-expressing levels, but also with higher AFB1-DNA adducts levels and increasing TP53M and portal vein tumor risk. The rs28383151 polymorphism modified the recurrence-free survival and overall survival of HCC patients, especially under high AFB1 exposure conditions. Additionally, this polymorphism multiplicatively interacted with the glutathione S-transferase M1 polymorphism with respect to HCC risk (ORinteraction = 2.13).

CONCLUSION

Genetic polymorphisms in the coding region of XRCC4 may be risk and prognostic biomarkers of AFB1-related HCC, and rs28383151 is such a potential candidate.

Tonsillar CD4+CD25+ regulatory T cells from IgA nephropathy patients have decreased immunosuppressive activity in experimental IgA nephropathy rats

BACKGROUND/AIM

CD4+CD25+ regulatory T (Treg) cells are of critical importance for maintenance of tolerance. We showed that the number of CD4+CD25+ Treg cells was significantly lower in tonsils of patients with IgA nephropathy (IgAN); however, the function of tonsillar CD4+CD25+ Treg cells in IgAN has not been reported. The aim of this study was to investigate the effect of tonsillar CD4+CD25+ Treg cells of IgAN patients on experimental IgAN in rats.

METHODS

Tonsillar CD4+CD25+ Treg cells were isolated by magnetic beads. A total of 2 × 10(6) CD4+CD25+ Treg cells were transferred into rats that were previously orally immunized over a period of 14 weeks and subsequently received an injection of BSA into the tail vein on 3 consecutive days. Urine protein and erythrocytes were measured. Glomerular injury was assessed by histopathology. Plasminogen activator inhibitor type 1 (PAI-1), interleukin (IL)-6 and transforming growth factor (TGF)-β1 in mesangial cells of rats were examined by reverse transcription PCR. Serum IgA and C3 and supernatants of IL-2, IL-4 and IL-6 in splenic cells were analysed by ELISA. Transferred tonsillar CD4+CD25+ Treg cells were tracked by reverse transcription PCR and flow cytometry.

RESULTS

IgA deposition in the mesangial region and the glomerular planar area and the number of cells, levels of serum IgA and supernatant IL-2, IL-4 and IL-6 in splenic cells and PAI-1, IL-6 and TGF-β1 expression in renal mesangial cells of rats that received CD4+CD25+ Treg cells from IgAN patients were significantly higher than in rats that received CD4+CD25+ Treg cells from the control group, although they were dramatically lower compared with rats treated without CD4+CD25+ Treg cells. Transferred tonsillar CD4+CD25+ Treg cells migrated predominantly to secondary lymphoid organs but not to the kidneys.

CONCLUSION

Dysfunction of tonsillar CD4+CD25+ Treg cells may be an important cause of IgAN progression.

Genetic variants in STAT4 and HLA-DQ genes confer risk of hepatitis B virus-related hepatocellular carcinoma

To identify genetic susceptibility loci for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in the Chinese population, we carried out a genome-wide association study (GWAS) in 2,514 chronic HBV carriers (1,161 HCC cases and 1,353 controls) followed by a 2-stage validation among 6 independent populations of chronic HBV carriers (4,319 cases and 4,966 controls). The joint analyses showed that HCC risk was significantly associated with two independent loci: rs7574865 at STAT4, P(meta) = 2.48 × 10(-10), odds ratio (OR) = 1.21; and rs9275319 at HLA-DQ, P(meta) = 2.72 × 10(-17), OR = 1.49. The risk allele G at rs7574865 was significantly associated with lower mRNA levels of STAT4 in both the HCC tissues and nontumor tissues of 155 individuals with HBV-related HCC (P(trend) = 0.0008 and 0.0002, respectively). We also found significantly lower mRNA expression of STAT4 in HCC tumor tissues compared with paired adjacent nontumor tissues (P = 2.33 × 10(-14)).

Anti-tumour effects of small interfering RNA targeting anion exchanger 1 in experimental gastric cancer

BACKGROUND AND PURPOSE

Anion exchanger 1 (AE1) is an integral membrane protein found in erythrocytes. Our previous studies have demonstrated that AE1 is expressed in human gastric cancer cells and may be involved in the carcinogenesis of cancer. In this study, we further investigated the role of AE1 in gastric carcinogenesis and the anti-tumour effects of AE1-targeted small interfering RNAs (siRNAs) in two experimental models of gastric cancer.

EXPERIMENTAL APPROACH

Molecular and cellular experiments were performed to elucidate the role of AE1 in the malignant transformation of gastric epithelium and the effects of AE1-targeted siRNAs on gastric cancer cells. The anti-tumour effect of the siRNA was evaluated in vivo in two mouse models, nude mice implanted with human gastric cancer xenografts (Model I) and mice with gastric cancer induced by N-methyl-N-nitrosourea (MNU) and Helicobacter pylori (Model II).

KEY RESULTS

AE1 was found to increase gastric carcinogenesis by promoting cell proliferation. AE1-targeted siRNA significantly suppressed AE1 expression and hindered tumour growth. Furthermore, the siRNA markedly decreased the detection rate of gastric cancer, in parallel with an increase in atypical hyperplasia at the end of the experiment in Model II.

CONCLUSIONS AND IMPLICATIONS

Knockdown of AE1 expression in gastric mucosa by administration of synthetic siRNAs significantly inhibits the growth of gastric cancer and decreases the detection rate of this tumour in experimental mice. These results suggest that AE1 is potentially a key therapeutic target and the silencing of AE1 expression in gastric mucosa could provide a new therapeutic approach for treating gastric cancer.

DNA repair gene XRCC7 polymorphisms (rs#7003908 and rs#10109984) and hepatocellular carcinoma related to AFB1 exposure among Guangxi population, China

AIM

  The X-ray repair cross-complementing group 7 (XRCC7) plays an important role in the repair of DNA double-strand breaks by nonhomologous end-joining repair (NEJR) pathway. However, the role of XRCC7 polymorphisms (rs#7003908 and rs#10109984) possibly influencing NEJR capacity in hepatocellular carcinoma (HCC) induced by aflatoxin B1 (AFB1) has not been well elaborated.

METHODS

  This hospital-based case-control study, including 348 patients with newly diagnosed HCC and 597 controls without any evidence of liver diseases, was conducted to elucidate the association between these two polymorphisms and the risk of HCC related to AFB1 exposure among a Guangxi population from a high AFB1-exposure area by means of TaqMAN-polymerase chain reaction technique.

RESULTS

  We observed that HCC patients featured higher AFB1 exposure than control group (odds ratios [OR] = 6.49 and 6.75 for exposure years and exposure levels, respectively). Furthermore, these individuals with the genotypes of XRCC7 rs#7003908 G alleles (namely XRCC7-TG or -GG), compared the homozygote of XRCC7 rs#7003908 T alleles (XRCC7-TT), faced increasing risk of HCC (OR, 3.45 and 5.04; 95% confidence intervals [CIs], 2.40-4.94 and 3.28-7.76, respectively). We also found some evidence that this polymorphism interacted with AFB1-expousure years or levels in the process of HCC carcinogenesis. Additionally, XRCC7 rs#7003908 polymorphism was correlated with the levels of AFB1-DNA adducts (r = 0.142, P < 0.001). XRCC7 rs#10109984 polymorphism, however, did not modify the risk of HCC related to AFB1 exposure (P > 0.05).

CONCLUSION

  These data suggest that XRCC7 rs#7003908 polymorphism may be one of the genetic modifiers for AFB1-related HCC among Guangxi population.

Polymorphism in xeroderma pigmentosum complementation group C codon 939 and aflatoxin B1-related hepatocellular carcinoma in the Guangxi population

Genetic polymorphisms in DNA repair genes may influence individual variations in DNA repair capacity, and this may be associated with the risk and outcome of hepatocellular carcinoma (HCC) related to aflatoxin B1 (AFB1) exposure. In this study, we focused on the polymorphism of xeroderma pigmentosum complementation group C (XPC) codon 939 (rs#2228001), which is involved in nucleotide excision repair. We conducted a case-control study including 1156 HCC cases and 1402 controls without any evidence of hepatic disease to evaluate the associations between this polymorphism and HCC risk and prognosis in the Guangxi population. AFB1 DNA adduct levels, XPC genotypes, and XPC protein levels were tested with a comparative enzyme-linked immunosorbent assay, TaqMan polymerase chain reaction for XPC genotypes, and immunohistochemistry, respectively. Higher AFB1 exposure was observed among HCC patients versus the control group [odds ratio (OR) = 9.88 for AFB1 exposure years and OR = 6.58 for AFB1 exposure levels]. The XPC codon 939 Gln alleles significantly increased HCC risk [OR = 1.25 (95% confidence interval = 1.03-1.52) for heterozygotes of the XPC codon 939 Lys and Gln alleles (XPC-LG) and OR = 1.81 (95% confidence interval = 1.36-2.40) for homozygotes of the XPC codon 939 Gln alleles (XPC-GG)]. Significant interactive effects between genotypes and AFB1 exposure status were also observed in the joint-effects analysis. This polymorphism, moreover, was correlated with XPC expression levels in cancerous tissues (r = -0.369, P < 0.001) and with the overall survival of HCC patients (the median survival times were 30, 25, and 19 months for patients with homozygotes of the XPC codon 939 Lys alleles, XPC-LG, and XPC-GG, respectively), especially under high AFB1 exposure conditions. Like AFB1 exposure, the XPC codon 939 polymorphism was an independent prognostic factor influencing the survival of HCC. Additionally, this polymorphism multiplicatively interacted with the xeroderma pigmentosum complementation group D codon 751 polymorphism with respect to HCC risk (OR(interaction) = 1.71).

CONCLUSION

These results suggest that the XPC codon 939 polymorphism may be associated with the risk and outcome of AFB1-related HCC in the Guangxi population and may interact with AFB1 exposure in the process of HCC induction by AFB1.

Genetic polymorphisms in DNA repair genes XPC, XPD, and XRCC4, and susceptibility to Helicobacter pylori infection-related gastric antrum adenocarcinoma in Guangxi population, China

Genetic polymorphisms in DNA repair genes may influence individual variation in DNA repair capacity, which may be associated with risk of gastric antrum adenocarcinoma (GAA) related to Helicobacter pylori infection. This study, including 361 GAAs and 616 controls without any evidence of tumors, was designed to evaluate the association between the polymorphisms of DNA repair genes XPC Ala499Val (RS#2228000) and Lys939Gln (RS#2228001), XPD Lys751Gln (RS#13181), and XRCC4 Ala247Ser (RS#3734091) and Ser298Asn (RS#1805377), and GAA risk for Guangxi population by means of TaqMan-PCR analysis. Increased risks of GAA were found for individuals with H. pylori positive [odds ratio (OR), 2.48; 95% confidence interval (CI), 1.84-3.33] or cagA positive (OR, 7.34; 95% CI, 5.46-9.87). No differences were observed among the studied groups with regard to the genotype distribution of XPC codons 499 and 939 and of XRCC4 codon 247; but XPD codon 751 genotypes with Gln [ORs (95% CI) were 2.67 (1.98-3.58) and 3.97 (2.64-5.99) for Lys/Gln and Gln/Gln, respectively] and XRCC4 codon 298 genotypes with Asn [ORs (95% CI) were 3.01 (2.21-4.10) and 4.78 (3.24-7.05) for Ser/Asn and Asn/Asn, respectively] increased the risk of GAA. Interestingly, there was an interactive effect between the risk genotypes of these two genes and cagA-positive status in the GAA risk (OR(interact) = 2.05 and 2.08, respectively). However, we did not find the gene-H. pylori-status interaction effects on the risk of GAA (P(interact) > 0.05). The results suggested that the polymorphisms of XPD codon 751 and XRCC4 codon 298 are associated with an increased risk of developing H. pylori-related GAA among Guangxi population.