Downregulation of LncRNA GCLC-1 Promotes Microcystin-LR-Induced Malignant Transformation of Human Liver Cells by Regulating GCLC Expression.

Microcystin-LR (MCLR) is an aquatic toxin, which could lead to the development of hepatocellular carcinoma (HCC). Long non-coding RNAs (lncRNAs) are considered important regulatory elements in the occurrence and development of cancer. However, the roles and mechanisms of lncRNAs during the process of HCC, induced by MCLR, remain elusive. Here, we identified a novel lncRNA, namely lnc-GCLC-1 (lncGCLC), which is in close proximity to the chromosome location of glutamate-cysteine ligase catalytic subunit (GCLC). We then investigated the role of lncGCLC in MCLR-induced malignant transformation of WRL68, a human hepatic cell line. During MCLR-induced cell transformation, the expression of lncGCLC and GCLC decreased continuously, accompanied with a consistently high expression of miR-122-5p. Knockdown of lncGCLC promoted cell proliferation, migration and invasion, but reduced cell apoptosis. A xenograft nude mouse model demonstrated that knockdown of lncGCLC promoted tumor growth. Furthermore, knockdown of lncGCLC significantly upregulated miR-122-5p expression, suppressed GCLC expression and GSH levels, and enhanced oxidative DNA damages. More importantly, the expression of lncGCLC in human HCC tissues was significantly downregulated in the high-microcystin exposure group, and positively associated with GCLC level in HCC tissues. Together, these findings suggest that lncGCLC plays an anti-oncogenic role in MCLR-induced malignant transformation by regulating GCLC expression.

The Glu69Asp Polymorphism of EME1 Gene is Associated with an Increased Risk of Hepatocellular Carcinoma in Guangxi Population, China.

Background: The dysfunction of Essential meiotic endonuclease 1 homolog 1 (EME1) can lead to genomic instability and tumorigenesis. Single nucleotide polymorphisms (SNPs) in the EME1 gene have been reported to be associated with the risk of several cancers, but its association with hepatocellular carcinoma (HCC) has not been investigated. This study aimed to determine the association between EME1 SNPs and the risk of HCC. Methods: This study included 645 HCC patients and 649 healthy controls from a Guangxi population of Southern China, and genotyped three functional SNPs (Glu69Asp: rs3760413A>C, Ile350Thr: rs12450550T>C, and rs11868055A>G) of the EME1 gene utilizing the Agena MassARRAY platform. Results: The rs3760413C variant genotypes (AC+CC: Glu/Asp+Asp/Asp) conferred a 1.419-fold risk of HCC compared to the AA (Glu/Glu) genotype (adjusted OR = 1.419, 95% CI = 1.017-1.980), and the allele C increased the risk of HCC in a dose-dependent manner (P trend = 0.017). Moreover, the effects of the rs3760413C variant genotypes were more pronounced in individuals who drank pond/ditch water (adjusted OR = 3.956, 95% CI = 1.413-11.076) than in those who never drank (P = 0.033). We further observed that a potential carcinogen microcystin-LR induced more DNA oxidative damages in peripheral blood mononuclear cells from the carriers of rs3760413C variant genotypes than those from the subjects with AA genotype (P = 0.006). A nomogram was also constructed combining the rs3760413A>C polymorphism and environmental risk factors for predicting HCC risk with a good discriminatory ability (concordance index = 0.892, 95% CI: 0.874-0.911) and good calibration (mean absolute error = 0.005). Conclusion: Our data suggest that the Glu69Asp missense polymorphism (rs3760413) of EME1 gene is associated with the risk of HCC, which may be a susceptible biomarker of HCC in the Guangxi population.

Genetic Variant of PP2A Subunit Gene Confers an Increased Risk of Primary Liver Cancer in Chinese.

BACKGROUND: Protein phosphatase 2A (PP2A, a serine/threonine phosphatase) is frequently inactivated in many types of cancer, including primary liver cancer (PLC). Genetic variations in PP2A subunits have been reported to be associated with the risk of many types of cancer but rarely in PLC. This study aims to assess the association between functional polymorphisms of PP2A subunit genes and the risk of PLC in Chinese. METHODS: In a case-control study with a total of 541 PLC patients and 547 controls in Guangxi province of Southern China, we genotyped six putatively functional polymorphisms (rs10421191G>A, rs11453459del>insG, rs1560092T>G, rs7840855C>T, rs1255722G>A and rs10151527A>C) of three PP2A subunit genes (PPP2R1A, PPP2R2A and PPP2R5E) using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry platform. RESULTS: The rs11453459insG variant genotypes (ins/ins+del/ins) of PPP2R1A were found to be significantly associated with an increased risk of PLC compared with the del/del genotype (adjusted OR = 1.290, 95% CI = 1.009-1.650), and the number of insert G allele worked in a dose-dependent manner (P trend= 0.007). The stratified analysis showed that the effects of rs11453459insG variant genotypes were more evident in the subgroup who drink pond-ditch water (adjusted OR = 3.051, 95% CI = 1.264-7.364) than those never drink (P = 0.041). The carriers of rs11453459 del/ins genotype had a significantly lower level of PPP2R1A mRNA expression in liver cancer tissues than those of the del/del genotype (P = 0.021). Furthermore, we used microcystin-LR, a carcinogen presents in the pond-ditch water, to treat human peripheral blood mononuclear cells and found that the cells from carriers of rs11453459insG variant genotypes induced more DNA oxidative damages than those from the del/del genotype carriers (P < 0.001). CONCLUSION: These findings suggest that the PPP2R1A rs11453459del>insG polymorphism is associated with an increased risk of PLC, especially for persons with a history of drinking pond-ditch water. This insertion/deletion polymorphism may be a susceptible biomarker for PLC in Chinese.

Relationship between vascular endothelial growth factor -2578C > a gene polymorphism and lung cancer risk: a meta-analysis.

BACKGROUND: Several reports were published on the relationship between the vascular endothelial growth factor (VEGF) -2578C > A gene polymorphism and lung cancer risk; however, the results are debatable. This meta-analysis was conducted to assess the relationship between VEGF -2578C > A gene polymorphism and lung cancer risk. METHODS: The associated literatures were identified on the 1st of September 2018 from CBM-disc (China Biological Medicine Database) and PubMed. RESULT: A total of 14 reports were recruited into our meta-analysis to assess the association between VEGF -2578C > A gene polymorphism and lung cancer susceptibility. There was a marked association between VEGF -2578C > A A allele / CC genotype and lung cancer risk in overall and Asian populations (overall populations: A allele: OR = 1.26, 95% CI: 1.08-1.46, P = 0.003; CC genotype: OR = 0.72, 95% CI: 0.54-0.95, P = 0.02; Asians: A allele: OR = 1.33, 95% CI: 1.15-1.55, P = 0.0002; CC genotype: OR = 0.68, 95% CI: 0.50-0.93, P = 0.01). However, VEGF -2578C > A gene polymorphism was not associated with the risk of lung cancer in Caucasians. CONCLUSION: VEGF -2578C > A A allele / CC genotype is associated with the lung cancer susceptibility in Asians and in overall populations.

Down-regulation of GCLC is involved in microcystin-LR-induced malignant transformation of human liver cells.

Microcystin-LR (MCLR) is a potent hepatotoxin which could lead to the development of hepatocellular carcinoma. However, the mechanisms of its carcinogenic action remain obscure. The catalytic subunit of glutamylcysteine ligase (GCLC) primarily regulates de novo synthesis of glutathione and is central to the antioxidant capacity of the cell, but emerging data suggest that the GCLC expression is associated with cancer development. The purpose of this study was to investigate the role and molecular mechanisms of GCLC in MCLR-induced malignant transformation of a human liver cell line WRL68. During MCLR-induced cell transformation, the expression of GCLC and activity of glutamate-cysteine ligase (GCL) decreased continuously, accompanied with consistent low levels of glutathione (GSH) but high levels of oxidative DNA damages. Furthermore, MCLR markedly inhibited protein phosphatase 2 A (PP2 A), and increased the level of GCLC phosphorylation. In contrast, overexpression of GCLC significantly enhanced the levels of GSH, inhibited oxidative DNA damages, and suppressed MCLR-induced cell invasion and migration, as well as tumor growth in nude mice. GCLC overexpression partially attenuated MCLR-induced PP2 A inhibition. Together, the current results suggest that down-regulation of GCLC is involved in MCLR-induced malignant transformation of human liver cells by inducing oxidative stress.

The role of ERCC1 and AFP gene polymorphism in hepatocellular carcinoma.

The aim of this study was to evaluate the effects of polymorphisms in excision repair cross-complementation group 1 (ERCC1) and alpha-fetoprotein (AFP) genes and their haplotypes on the susceptibility to hepatocellular carcinoma (HCC), and to decipher the association between single-nucleotide polymorphisms (SNPs) and clinicopathologic characteristics of HCC.Peripheral blood DNA was extracted from 206 subjects. SNaPshot technique was used for genotyping 5 SNP sites of the ERCC1 rs735482, rs1046282, rs3212948, and AFP rs737241, rs4024 genotypes. Chi-squared test and logistic regression model were used to analyze the relationship of different genotypes or haplotype and the susceptibility and clinicopathologic characteristics of HCC.The frequency of GG.GA and AA genotypes at the AFP rs737241 site in the case and control groups showed statistically significant differences (P < .05). The risk of HCC in subjects carrying mutated allele A (GA+AA) was increased by 0.543-times (P < .05) compared to that in the subjects with the GG genotype. Significant differences were observed in the linkage disequilibrium between 2 of the five SNPs (P < .05); the frequency of ERCC1 C-C and AFP A-A haplotypes was significantly lower in the case group than in the control group (P < .05). The results of clinicopathologic analysis showed that A allele at the rs737241 locus could increase the expression level of AFP (P = .007), the rs1046282 mutation C allele could increase the AFP expression level (P = .011), rs4024 locus mutation A allele could reduce the risk of vascular invasion (P = .013), rs3212948 locus mutation T allele could reduce the differentiation of liver cancer (P = .022), rs1046282 locus C allele could reduce the DNA load of hepatitis B virus (P = .035), and rs735482 A allele could increase the tumor size in HCC (P = .037).The SNPs in rs737241 for AFP gene may correlate with the occurrence of HCC. The SNPs in ERCC1 and AFP genes may affect the prognosis of HCC, offering reliable information for early prediction of tumor progression and diagnosis of HCC.

NBS1 rs2735383 polymorphism is associated with an increased risk of laryngeal carcinoma.

BACKGROUND: Nijmegen breakage syndrome 1 (NBS1), as a key protein in the DNA double-strand breaks (DSBs) repair pathway, plays an important role in maintaining genomic stability. Although single nucleotide polymorphisms (SNPs) in NBS1 have frequently been studied in multiple cancers, the relationships of two functional NBS1 polymorphisms (rs2735383 and rs1805794) with laryngeal carcinoma are yet unclear. Therefore, in the present study, we performed a case-control study including 342 cases and 345 controls to analyze the associations between two polymorphisms of NBS1 and the risk of laryngeal carcinoma. METHODS: We used the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to determine the genotypes of the functional SNPs in NBS1 gene. RESULTS: In comparison with the homozygous rs2735383GG genotype, the CC genotype was significantly associated with an increased risk of laryngeal carcinoma (adjusted OR = 1.884, 95%CI = 1.215-2.921). The rs2735383C variant genotypes (GC + CC) conferred a 1.410-fold increased risk of laryngeal carcinoma (adjusted OR = 1.410, 95%CI = 1.004-1.980). Furthermore, when compared to rs2735383GG genotype in laryngeal carcinoma tissues, the combined GC and CC genotypes exerted a significantly lower mRNA level of NBS1 (P = 0.003). In contrast, no significant association was found between rs1805794G > C polymorphism and cancer risk (adjusted OR = 1.074, 95%CI = 0.759-1.518 for GC; adjusted OR = 1.100, 95%CI = 0.678-1.787 for CC; adjusted OR = 1.079, 95%CI = 0.774-1.505 for GC + CC). CONCLUSIONS: These findings indicate that rs2735383G > C polymorphism in NBS1 may play a crucial role in the development of laryngeal carcinoma.

The ERCC1-4533/8092, TNF-α 238/308 polymorphisms and the risk of hepatocellular carcinoma in Guangxi Zhuang populations of China: Case-control study.

OBJECTIVE: To investigate the relationship between excision repair cross-complementing group 1 (ERCC1)-4533/8092, tumor necrosis factor-alpha (TNF-α)-238/308 polymorphisms, and the risk of hepatocellular carcinoma (HCC) in Guangxi Zhuang population of China. METHODS: Polymerase chain reaction-restriction fragment length polymorphism method was used to detect the ERCC1-4533/8092 and TNF-α-238/308 polymorphisms in 88 cases with HCC and 82 cases of normal control. RESULTS: There were no differences in the frequency distribution of ERCC1-4533 and TNF-α-238 polymorphisms in the HCC group and the control group (P > 0.05). The genotype frequency distributions of the ERCC1-8092 and TNF-α-308 in the HCC group and the control group were different (P < 0.05). Compared with ERCC1-8092 CC genotype, ERCC1-C8092 CA/AA genotype had higher risk of HCC (CA/AA vs CC; odds ratio 3.51, 95% confidence interval 1.03-12.016). Compared with TNF-α-308 GG genotype, TNF-α-308 GA/AA genotype was significantly associated with an increased risk of HCC (GA/AA vs GG; odds ratio 3.84, 95% confidence interval 1.011-14.57). CONCLUSION: The genetic polymorphisms of ERCC1-8092 and TNF-α-308 are associated with the risk of HCC in Guangxi Zhuang population of China.

Association of glutathione S-transferase P1 gene polymorphism with the risk of small-cell carcinoma of lung cancer.

The conclusions of the published reports on the relationship between glutathione S-transferase P1 (GSTP1) gene polymorphism and the risk of small-cell carcinoma of lung cancer are still debated. GSTP1 is one of the important mutant sites reported at present. This meta-analysis was performed to evaluate the association between GSTP1 and the risk of small-cell carcinoma of lung cancer. The association investigations were identified from PubMed and Cochrane Library, and eligible studies were included and synthesized using meta-analysis method. Ten reports were included into this meta-analysis for the association of GSTP1 A/G gene polymorphism and small-cell carcinoma of lung cancer. The G allele and GG genotype were not associated with the susceptibility of risk of small-cell carcinoma in overall populations, East-Asians and Turkish population. However, there was an association between GG genotype with the risk of small-cell carcinoma in Caucasians. In conclusion, GG genotype was associated with the risk of small-cell carcinoma in Caucasian patients with lung cancer. However, GSTP1 A/G gene polymorphism is not associated with the susceptibility of small-cell carcinoma in overall populations, East-Asians and Turkish population.

Association of vitamin D receptor BsmI gene polymorphism with the risk of type 2 diabetes mellitus.

Relationship between vitamin D receptor (VDR) BsmI (rs1544410) gene polymorphism and the type 2 diabetes mellitus (T2DM) susceptibility is still conflicting at present. This meta-analysis was conducted to assess the association between VDR BsmI gene polymorphism and the risk of T2DM. The association studies were identified from PubMed, and Cochrane Library on 1 January 2014, and eligible investigations were included and synthesized using meta-analysis method. Eleven reports were recruited into this meta-analysis for the association of VDR BsmI gene polymorphism with T2DM susceptibility. In overall populations, B allele, BB genotype and bb genotype were not associated with T2DM risk. VDR BsmI gene polymorphism was also not associated with the T2DM risk in Asians and Caucasians. In conclusion, VDR BsmI gene polymorphism was also not associated with T2DM risk in overall populations, Asians and Caucasians. However, more studies should be conducted to confirm it.

Association of vitamin D receptor gene polymorphism with the risk of renal cell carcinoma: a meta-analysis.

Relationship between vitamin D receptor (VDR) gene polymorphism and the risk of renal cell carcinoma from the published reports are still conflicting. This study was conducted to evaluate the relationship between VDR ApaI (rs7975232), BsmI (rs1544410), TaqI (rs731236), and Fok1 (rs2228570) gene polymorphism and the risk of renal cell carcinoma using meta-analysis method. The association studies were identified from PubMed, and Cochrane Library on 1 March 2014, and eligible investigations were included and synthesized using meta-analysis method. Five reports were recruited into this meta-analysis for the association of VDR gene polymorphism with renal cell carcinoma susceptibility. In this meta-analysis, the ApaI AA genotype, BsmI BB genotype, Fok1 f allele, and Fok1 FF genotype were associated with the risk of renal cell carcinoma in Asians. However, VDR ApaI, BsmI, TaqI, and Fok1 gene polymorphism were not associated with the risk of renal cell carcinoma in overall populations and in Caucasians. In conclusion, the ApaI AA genotype, BsmI BB genotype, Fok1 f allele, and Fok1 FF genotype were associated with the risk of renal cell carcinoma in Asians. However, more studies should be conducted to confirm it.

Association of transforming growth factor-ß1 T869C, G915C, and C509T gene polymorphisms with rheumatoid arthritis risk.

The association of transforming growth factor-ß1 (TGFß1) is an important signaling pathway factor involving extracellular matrix regulation, and its gene polymorphisms with the risk of rheumatoid arthritis (RA) is currently still fiercely debated. Therefore, this meta-analysis was performed to determine if TGFß1 T869C, G915C, and C509T gene polymorphisms correlate with the risk of developing RA. Association reports were identified from PubMed, Cochrane Library and CBM-disc (China Biological Medicine Database) on 1 May 2013, and eligible studies were recruited and synthesized to identifying patterns among study results. T869C TT genotype in the overall population was associated with increased RA risk (OR = 1.28, 95% CI: 1.02-1.60, p = 0.03). In the sub-group analysis, T869C TT genotype was shown to be a risk factor for RA, and T869C C allele or CC genotype a protective factor against RA disease in Asians, but these associations were not found in Caucasians. Furthermore, TGFß1 C509T TT genotype was distinctly associated with RA susceptibility, but the T allele and CC genotype were not. TGFß1 G915C gene polymorphism was not associated with RA susceptibility. In conclusion, the TT genotype of TGFß1 T869C was associated with RA risk in the overall population and Asians. Furthermore, CC genotype or C allele was determined to be protective factors with respect to the RA risk in the overall population and Asians. Nonetheless, additional studies are required to firmly establish a correlation between the aforementioned polymorphisms and RA risk.

[Correlation between expression of the Tiam1 gene and the invasion and metastasis in nasopharyngeal carcinoma].

OBJECTIVE: To study the relation between T lymphoma invasion/metastasis1 (Tiam1) gene and nasopharyngeal carcinoma progression. METHOD: Using of reverse transcription polymerase chain (RT-PCR) technique on 41 nasopharyngeal carcinoma tissue and 20 normal nasopharyngeal tissue to proceed the test of mRNA overexpression. RESULT: Average expression of the Tiam1 gene in nasopharyngeal carcinoma tissue (1.183 +/- 0.73) is higher than in normal nasopharyngeal tissue (0.87 +/- 0.45) (P < 0.01). The positive relationship between the frequency of Tiam1 overexpression and clinical staging and T staging was very significant (P < 0.05) and increased gradually; The frequency of Tiam1 overexpression was 59.3% (16/27) in patients with lymph node metastasis, 21.4% (3/ 14) in patients without lymph node metastasis, overexpression between them was very significant (P < 0.05). CONCLUSION: Average expression of the Tiam1 gene in nasopharyngeal carcinoma tissue is higher than in normal nasopharyngeal tissue. Our data suggest that the overexpression of the Tiam1 gene correlates invasion and metastasis of nasopharyngeal carcinoma.