Association of telomere length in peripheral leukocytes with chronic hepatitis B and hepatocellular carcinoma

Single nucleotide polymorphisms in telomere length-related genes are associated with hepatocellular carcinoma risk in the Chinese Han population

Background

Single nucleotide polymorphisms (SNPs) in telomere-related genes are associated with a high risk of hepatocellular carcinoma (HCC). In this study, we investigated the SNPs of telomere length-related genes and their correlation with HCC risk in the Chinese Han population.

Materials and methods

A total of 473 HCC patients and 564 healthy volunteers were recruited. Overall, 42 SNPs distributed in telomere-related genes were selected and identified. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

We found rs6713088 (OR = 1.27, 95% CI = 1.07-1.52, p = 0.007), rs843711 (OR = 1.29, 95% CI = 1.09-1.54, p = 0.004) and rs843706 (OR = 1.30, 95% CI = 1.09-1.55, p = 0.003) in the ACYP2 gene, rs10936599 (OR = 1.21, 95% CI = 1.02-1.44, p = 0.032) in the TERC gene and rs7708392 (OR = 1.24, 95% CI = 1.00-1.52, p = 0.042) in the TNIP1 gene were associated with high HCC risk (OR > 1). In contrast, rs1682111 (OR = 0.77, 95% CI = 0.64-0.94, p = 0.008) in the ACYP2 gene, rs2320615 (OR = 0.79, 95% CI = 0.64-0.99, p = 0.038) in the NAF1 gene, rs10069690 (OR = 0.75, 95% CI = 0.59-0.96, p = 0.021) and rs2242652 (OR = 0.70, 95% CI = 0.55-0.90, p = 0.004) in the TERT gene were associated with low HCC risk (OR < 1). Based on genotype frequency distributions, rs6713088, rs843645, rs843711 and rs843706 located in the ACYP2 gene as well as rs10936599 in the TERC gene were associated with a high incidence of HCC (p < 0.05). In addition, SNPs in these genes could form a linkage imbalance haplotype. Specifically, the haploid 'GC' formed by rs10069690 and rs2242652 within the TERT gene increased the risk of HCC (p < 0.05).

Conclusion

SNPs in ACYP2, TERC, TERT and other genes were correlated with HCC risk in the Chinese Han population. These data may provide new insights into early diagnosis and screening of HCC.

Leukocyte telomere length as a diagnostic biomarker for anti-tuberculosis drug-induced liver injury

Despite being relatively rare, anti-tuberculosis drug-induced liver injury (ATDILI) is a leading cause of acute liver failure and a major reason for treatment discontinuation, because of no specific and selective markers for ATDILI. Herein, this study aimed to investigate whether telomere length, a biological indicator of age-related diseases, is associated with ATDILI outcomes and could serve as an early ATDILI biomarker. Relative telomere length (RTL) in blood leukocyte of 100 age- and gender-matched healthy controls, 49 tuberculosis patients with ATDILI, and 53 tuberculosis patients with non-ATDILI was quantified using real-time polymerase chain reaction. Both tuberculosis patients with and without ATDILI had significantly shorter RTL than healthy controls. Compared with tuberculosis patients with non-ATDILI, RTL in those with ATDILI was significantly increased. Longer RTL was found to be significantly associated with increased susceptibility to ATDILI. Multivariate linear regression analysis showed that an increment in RTL was independently correlated with elevated values of aspartate aminotransferase and alanine aminotransferase assessed within 60 days after anti-tuberculosis treatment. Kaplan-Meier curve analysis demonstrated that longer RTL was associated with elevated rates of hepatotoxicity in tuberculosis patients. Receiver-operating characteristic curve analysis unveiled a diagnostic accuracy of RTL as a novel indicator for ATDILI progression (AUC = 0.73), which yielded more sensitive and specific values than traditional liver biomarkers including serum enzyme activities of aminotransferases measured within 7 days after treatment with anti-tuberculosis regimens. Collectively, aberrant RTL in blood leukocyte would reflect hepatotoxicity induced by anti-tuberculosis agents and might have a potential biomarker for early ATDILI progression.

Impact of direct-acting antivirals on leukocytic DNA telomere length in hepatitis C virus-related hepatic cirrhosis

BACKGROUND

Direct-acting antiviral (DAAs) represent advancement in the management of hepatitis C virus (HCV)-related hepatic cirrhosis. A high proportion of patients achieve a sustained virologic response; eradication of HCV is coupled with a decreased risk of hepatocellular carcinoma. Recent evidence suggests that shortening of the DNA telomere may be linked to cellular senescence as well as predisposition to malignant transformation.

OBJECTIVE

This study aimed to assess pretreatment leukocytic DNA telomere length in HCV-related cirrhosis and post viral eradication using DAAs.

PATIENTS AND METHODS

This study included 24 patients with HCV-related cirrhosis, Child-Pugh A. Whole-blood samples were obtained from patients before treatment and 12 weeks after the end of treatment, as well as from 24 healthy controls. Terminal restriction fragment, corresponding to telomere length, was measured using a nonradioactive Southern blot technique, detected by chemiluminescence.

RESULTS

DNA telomere length was significantly shorter before treatment compared with 12 weeks after end of treatment in HCV-related cirrhotic patients. Also, it was significantly shorter in patients before treatment compared with healthy individuals.

CONCLUSION

Telomere elongation in blood leukocytes can be considered a marker of recovery of inflammation after DAAs-induced HCV eradication. Still, the possibility of activation by cancer initiation cannot be excluded.

Significant SNPs Related to Telomere Length and Hepatocellular Carcinoma Risk in Chronic Hepatitis B Carriers

Chronic hepatitis B virus (HBV) infection increases the risk of developing cirrhosis and hepatocellular carcinoma (HCC) with suspected interactions between virus replication and host immune responses. A number of reports have suggested that telomerase function may be involved in chronic hepatitis B (CHB) pathogenesis, but positive or negative associations with HCC risk remain for discussion. Mean telomere length is an indicator of biological aging and it has been reported that reduction in NBV carriers compared to normal individuals. In somatic cells, telomeres contain simple, tandemly repeated G-rich sequences that frequently are reduced by 50 to 200 base pairs at each cell division. Several genome-wide association studies (GWAS) in diverse ethnic populations have revealed eleven single nucleotide polymorphisms (SNPs) linked to telomere length. Two of these, rs398652 and rs621559, have prognostic value and could be used as genetic markers. This review describes current knowledge concerning telomerase activity and telomere length as well as significant polymorphisms in HBV-related HCC patients. In particular, to cast light on genotype-phenotype interactions, we used SNPnexus to evaluate effects of the two SNPs on risk of disease and complex disorders.

Association of TERT polymorphisms with chronic hepatitis B in a Chinese Han population

In this study, we investigated the association between the polymorphisms of telomerase reverse transcriptase (TERT) gene and the risk of chronic hepatitis B (CHB) in a Chinese Han population. Four single nucleotide polymorphisms (SNPs) in TERT (rs10069690, rs2242652, rs2853677 and rs2853676) were genotyped from 224 CHB patients and 300 healthy controls using the Sequenom Mass-ARRAY platform. We used genetic model, haplotype analyses, chi-square test, logistic regression analysis to evaluate the association between SNPs and CHB risk. The relative risk was estimated by odd ratios (ORs) and 95% confidence intervals (CIs). We found that rs10069690 was significantly associated with an increased CHB risk in the dominant model (adjusted OR = 1.70, 95% CI: 1.06–2.71, P = 0.031) and additive model (adjusted OR = 1.62, 95% CI: 1.09–2.41, P = 0.018). The haplotype “TA” (rs10069690 and rs2242652) was found to be associated with an increased risk of CHB (adjusted OR = 1.58, 95% CI: 1.05–2.38, P = 0.027). Our results suggested potential genetic contributes for TERT in CHB development in a Chinese Han population. Future functional and association studies with larger sample sizes are required to confirm these findings.

Genetic association of telomere length with hepatocellular carcinoma risk: A Mendelian randomization analysis

BACKGROUND

Observational studies show an association between telomere length and Hepatocellular carcinoma (HCC) risk, but the relationship is controversial. Particularly, it remains unclear whether the association is due to confounding or biases inherent in conventional epidemiological studies. Here, we applied Mendelian randomization approach to evaluate whether telomere length is causally associated with HCC risk.

METHODS

Individual-level data were from HBV-related HCC Genome-wide association studies (1,538 HBV positive HCC patients and 1,465 HBV positive controls). Genetic risk score, as proxy for actual measured telomere length, derived from nine telomere length-associated genetic variants was used to evaluate the effect of telomere length on HCC risk.

RESULTS

We observed a significant risk signal between genetically increased telomere length and HBV-related HCC risk (OR=2.09, 95% CI 1.32-3.31, P=0.002). Furthermore, a U-shaped curve was fitted by the restricted cubic spline curve, which indicated that either short or long telomere length would increase HCC risk (P=0.0022 for non-linearity test). Subgroup analysis did not reveal significant heterogeneity between different age, gender, smoking status and drinking status groups.

CONCLUSIONS

Our results indicated that a genetic background that favors longer or shorter telomere length may increase HBV-related HCC risk-a U-shaped association.