Diversity of the association of serum levels and genetic variants of MHC class I polypeptide-related chain A with liver fibrosis in chronic hepatitis C

Association between MICA rs2596542 Polymorphism with the Risk of Hepatocellular Carcinoma in Chronic Hepatitis C Patients

In this study we investigated the impact of rs2596542A/G single nucleotide polymorphism (SNP) in the major histocompatibility complex class I chain-related sequence A (MICA) gene on HCV-induced hepatocellular carcinoma (HCC) susceptibility in a Brazilian population. In total, 252 HCV-infected patients (98 with HCV-induced HCC and 154 non-malignant HCV-induced liver cirrhosis) were enrolled and 98 healthy control subjects (negative anti-HCV). The MICA rs2596542 SNP genotypes were determined by real-time PCR assay. No differences in MICA genotype frequencies between HCV-induced cirrhosis patients and controls were observed. However, genotype frequencies of rs2596542A/G SNP were statistically different between HCV-induced HCC patients and controls (p = 0.048), and also between HCC and HCV-induced cirrhosis patients (p = 0.039). The highest frequency of the rs2596542AA genotype was observed in HCC patients (31.6%) when compared with HCV-induced cirrhosis patients (18.8%) and healthy controls (19.4%). Also, rs2596542AA genotype carriers have an increased risk for HCC when compared to HCV-induced cirrhosis status [odds ratio (OR) = 1.99; 95% confidence interval (CI) = 1.06-3.74, p = 0.020)] and healthy individuals (OR = 1.92, 95% CI = 1.00-3.70, p = 0.049). Taken together our study suggest that MICA rs2596542 SNP impacts HCV-induced HCC susceptibility suggesting that genetic variants in MICA are of clinical relevance to hepatocarcinogenesis by impacting host immune response in chronic HCV infection.

Association of hyperuricemia with disease severity in chronic hepatitis C patients

BACKGROUND/AIMS

Hepatitis C virus (HCV) infection is associated with extrahepatic manifestations such as metabolic abnormalities. The association between chronic hepatitis C (CHC) and uric acid levels has rarely been investigated. We aimed to evaluate the levels of serum uric acid in CHC patients.

METHODS

Three hundred and seventy-three histologically confirmed CHC patients who were scheduled to receive antiviral therapy were consecutively enrolled, and 746 age- and sex-matched uninfected controls were included for comparison. Hyperuricemia was defined as a uric acid level > 7 mg/dL in men and > 6.0 mg/dL in women.

RESULTS

Hyperuricemia was identified in 15.8% of the CHC patients. The uric acid levels did not differ between the CHC patients and the controls (5.54 ± 1.20 mg/dL vs. 5.45 ± 1.45 mg/dL, P = 0.3). Among the 373 CHC patients, the factors associated with hyperuricemia included body mass index (BMI) (OR/CI: 1.13/1.04-1.21, P = 0.003) and estimated glomerular filtration rate (eGFR) (OR/CI: 0.98/0.97-1.00, P = 0.02). Logistic regression analysis revealed that the factors associated with hyperuricemia in male patients included BMI (OR/CI: 1.12/1.05-1.30, P = 0.006) and advanced fibrosis (F3-4) (OR/CI: 0.27/0.09-0.83, P = 0.02), whereas the factors associated with hyperuricemia in female patients included eGFR (OR/CI: 0.97/0.95-0.99, P = 0.02) and diabetes (OR/CI: 3.03/1.11-8.25, P = 0.03). There was a significant decreasing trend of serum uric acid levels with the progression of fibrotic stages among male patients (6.21 ± 1.03 mg/dL 5.82 ± 1.16 mg/dL and 5.44 ± 1.28 mg/dL in stages F0-2, F3, and F4, respectively, trend P = 0.01).

CONCLUSIONS

Hyperuricemia was inversely associated with liver disease severity in CHC male patients.

Lower protein expression levels of MHC class I chain-related gene A in hepatocellular carcinoma are at high risk of recurrence after surgical resection

MHC class I chain-related gene A (MICA) variants have been associated with hepatocellular carcinoma (HCC). Their association with MICA expression in cancer cells and cancer recurrence is unknown. SNP rs2596542 of MICA was tested in 193 HCC patients with surgical resection. The corresponding MICA expression in the cancer tissue was measured by immunochemistry microarray. Patients with the SNP rs2596542 A allele had significantly lower MICA expression in tumor tissue than did those with the GG genotype (24.7 ± 15.1% vs. 41.5 ± 23.4%, P < 0.001). Patients who had HCC recurrence had significantly lower MICA expression in tumor tissue (34.2 ± 21.8% vs. 24.0 ± 19.8%, P = 0.03). Cox regression analysis revealed that the factors independently predictive of HCC recurrence included low MICA expression (hazard ratio [HR]/95%confidence intervals [CI]: 2.77/1.07–7.14, P = 0.035) and tumor size (HR/CI: 5.22/2.11–12.96, P < 0.001). Compared to patients with tumors <5 cm and MICA expression >30%, patients with either one and both two risk factors had HCC HRs of 9.76 (C.I. 1.27–75.03, P = 0.03) and 27.30 (C.I. 3.46–215.6, P = 0.002), respectively. We concluded that low cellular MICA expressions were at a greater risk of HCC recurrence after curative treatment.

Tolloid-like 1 genetic variants determine fibrosis regression in chronic hepatitis C patients with curative antivirals

Hepatitis C virus (HCV) eradication by antivirals promote fibrosis modification. Whether host genetics determined fibrosis regression in chronic hepatitis C (CHC) patients with sustained virological response (SVR) is to be determined. One hundred and fifty-six SVR patients with paired liver biopsy before and after antivirals were enrolled. Host genetic factors including single nucleotide polymorphism rs17047200 of tolloid-like 1(TLL-1) were analyzed for their association with fibrosis modification. The proportions of improved, unchanged and worsening fibrotic stags were 39.1% (n = 61), 39.1% (n = 61), and 21.8% (n = 34), respectively. The rate of annual fibrotic improvement was 0.16 ± 0.79. There was a significant trend of increased fibrotic improvement rate in patients from F01 to F4 (P < 0.001). However, the rate of improvement seemed more limited in cirrhotic patients among those with advanced liver disease. Patients with fibrotic improvement had a significantly higher proportion of TLL-1 rs17047200 AA genotype compared to those without (92.5% vs. 79.3%, p = 0.039). Logistic regression analysis revealed that the TLL-1 rs17047200 AA genotype was the only independent factor associated with fibrosis improvement (odds ratio/95% confidence intervals: 3.2/1.01-10.12, p = 0.047). Compared with TLL-1 rs17047200 non-AA carriers, a significantly higher proportion of fibrosis improvement in AA genotype carriers was observed among patients with F0-2 (33.3% vs. 0%, p = 0.005) but not with F34 (70% vs. 80%, p = 1). We concluded that TLL-1 genetic variants determined fibrotic improvement in CHC with curative antivirals, particularly in patients with mild liver disease.

Risk factors and prevention of hepatocellular carcinoma in the era of precision medicine

Patients who develop chronic fibrotic liver disease, caused by viral or metabolic aetiologies, are at a high risk of developing hepatocellular carcinoma (HCC). Even after complete HCC tumour resection or ablation, the carcinogenic tissue microenvironment in the remnant liver can give rise to recurrent de novo HCC tumours, which progress into incurable, advanced-stage disease in most patients. Thus, early detection and prevention of HCC development is, in principle, the most impactful strategy to improve patient prognosis. However, a "one-size-fits-all" approach to HCC screening for early tumour detection, as recommended by clinical practice guidelines, is utilised in less than 20% of the target population, and the performance of screening modalities, including ultrasound and alpha-fetoprotein, is suboptimal. Furthermore, optimal screening strategies for emerging at-risk patient populations, such as those with chronic hepatitis C after viral cure, or those with non-cirrhotic, non-alcoholic fatty liver disease remain controversial. New HCC biomarkers and imaging modalities may improve the sensitivity and specificity of HCC detection. Clinical and molecular HCC risk scores will enable precise HCC risk prediction followed by tailoured HCC screening of individual patients, maximising cost-effectiveness and optimising allocation of limited medical resources. Several aetiology-specific and generic HCC chemoprevention strategies are evolving. Epidemiological and experimental studies have identified candidate chemoprevention targets and therapies, including statins, anti-diabetic drugs, and selective molecular targeted agents, although their clinical testing has been limited by the lengthy process of cancer development that requires long-term, costly studies. Individual HCC risk prediction is expected to overcome the challenge by enabling personalised chemoprevention, targeting high-risk patients for precision HCC prevention and substantially improving the dismal prognosis of HCC.