MBOAT7-TMC4 rs641738 Is Not Associated With the Risk of Hepatocellular Carcinoma or Persistent Hepatitis B Infection

Personalized medicine and nutrition in hepatology for preventing chronic liver disease in Mexico

Chronic liver disease is a global health issue. Patients with chronic liver disease require a fresh approach that focuses on the genetic and environmental factors that contribute to disease initiation and progression. Emerging knowledge in the fields of Genomic Medicine and Genomic Nutrition demonstrates differences between countries in terms of genetics and lifestyle risk factors such as diet, physical activity, and mental health in chronic liver disease, which serves as the foundation for the implementation of Personalized Medicine and Nutrition (PerMed-Nut) strategies. Most of the world's populations have descended from various ethnic groupings. Mexico's population has a tripartite ancestral background, consisting of Amerindian, European, and African lineages, which is common across Latin America's regional countries. The purpose of this review is to discuss the genetic and environmental components that could be incorporated into a PerMed-Nut model for metabolic-associated liver disease, viral hepatitis B and C, and hepatocellular carcinoma in Mexico. Additionally, the implementation of the PerMed-Nut approach will require updated medicine and nutrition education curricula. Training and equipping future health professionals and researchers with new clinical and investigative abilities focused on preventing liver illnesses in the field of genomic hepatology globally is a vision that clinicians and nutritionists should be concerned about.

Association of MBOAT7 rs641738 polymorphism with hepatocellular carcinoma susceptibility: A systematic review and meta-analysis

BACKGROUND

The MBOAT7 rs641738 single-nucleotide polymorphism (SNP) has been proven to influence various liver diseases, but its association with hepatocellular carcinoma (HCC) susceptibility has been debated. To address this discrepancy, we conducted the current systematic review and meta-analysis.

AIM

To perform a systematic review and meta-analysis on association of MBOAT7 SNP and HCC susceptibility.

METHODS

We performed a systematic review in PubMed, Web of Science, Scopus, and EMBASE; applied specific inclusion and exclusion criteria; and extracted the data. Meta-analysis was conducted with the meta package in R. Sensitivity and subgroup analyses were also performed. This meta-analysis was registered in PROSPERO (CRD42023458046).

RESULTS

Eight studies were included in the systematic review, and 12 cohorts from 6 studies were included in the meta-analysis. Our meta-analysis revealed an association between the MBOAT7 SNP and HCC susceptibility in both the dominant [odds ratio (OR): 1.14, 95% confidence interval (95%CI): 1.02-1.26, P = 0.020] and recessive (OR: 1.21, 95%CI: 1.05-1.39, P = 0.008) models. Subgroup analysis revealed that stratification of the included patients by geographical origin showed a significant association in Asia (OR: 1.20, 95%CI: 1.03-1.39).

CONCLUSION

This meta-analysis underscores the contribution of the MBOAT7 rs641738 SNP to hepatocarcinogenesis, especially in Asian populations, which warrants further investigation.

MBOAT7 rs641738 Variant Is Not Associated with an Increased Risk of Hepatocellular Carcinoma in a Latin American Cohort

BACKGROUND

The rs641738 C > T single-nucleotide polymorphism of MBOAT7 has been associated with hepatocellular carcinoma (HCC) and nonalcoholic fatty liver disease (NAFLD). Latin Americans have high rates of HCC and NAFLD, but no assessment between MBOAT7 and HCC has been performed in this population.

AIMS

We provide the first assessment of the impact of MBOAT7 on HCC risk in Latin Americans.

METHODS

Patients were prospectively recruited into the ESCALON network, designed to collect samples from Latin American patients with HCC in 6 South American countries (Argentina, Ecuador, Brazil, Chile, Peru, and Colombia). A European cohort and the general Hispanic population of gnomAD database were included for comparison. Associations between HCC and MBOAT7 were evaluated using logistic regression.

RESULTS

In total, 310 cases of HCC and 493 cases of cirrhosis without HCC were assessed. The MBOAT7 TT genotype was not predictive of HCC in Latin Americans (TT vs CC OR adjusted = 1.15, 95% CI 0.66-2.01, p = 0.610) or Europeans (TT vs CC OR adjusted = 1.20, 95% CI 0.59-2.43, p = 0.621). No significant association was noted on subgroup analysis for NAFLD, viral hepatitis, or alcohol-related liver disease. The TT genotype was increased in the NAFLD-cirrhosis cohort of Latin Americans compared to a non-cirrhotic NAFLD cohort (TT vs CC + CT OR = 2.75, 95% CI 1.10-6.87, p = 0.031).

CONCLUSION

The rs631738 C > T allele of MBOAT7 was not associated with increased risk of HCC in Latin Americans or Europeans. An increase in the risk of cirrhosis was noted with the TT genotype in Latin Americans with NAFLD.

MBOAT7 in liver and extrahepatic diseases

MBOAT7 is a protein anchored to endomembranes by several transmembrane domains. It has a catalytic dyad involved in remodelling of phosphatidylinositol with polyunsaturated fatty acids. Genetic variants in the MBOAT7 gene have been associated with the entire spectrum of non-alcoholic fatty liver (NAFLD), recently redefined as metabolic dysfunction-associated fatty liver disease (MAFLD) and, lately, steatotic liver disease (SLD), and to an increasing number of extrahepatic conditions. In this review, we will (a) elucidate the molecular mechanisms by which MBOAT7 loss-of-function predisposes to MAFLD and neurodevelopmental disorders and (b) discuss the growing number of genetic studies linking MBOAT7 to hepatic and extrahepatic diseases. MBOAT7 complete loss of function causes severe changes in brain development resulting in several neurological manifestations. Lower MBOAT7 hepatic expression at both the mRNA and protein levels, due to missense nucleotide polymorphisms (SNPs) in the locus containing the MBOAT7 gene, affects specifically metabolic and viral diseases in the liver from simple steatosis to hepatocellular carcinoma, and potentially COVID-19 disease. This body of evidence shows that phosphatidylinositol remodelling is a key factor for human health.

Membrane-bound O-acyltransferase 7 (MBOAT7)-driven phosphatidylinositol remodeling in advanced liver disease

Advanced liver diseases account for approximately 2 million deaths annually worldwide. Roughly, half of liver disease-associated deaths arise from complications of cirrhosis and the other half driven by viral hepatitis and hepatocellular carcinoma. Unfortunately, the development of therapeutic strategies to treat subjects with advanced liver disease has been hampered by a lack of mechanistic understanding of liver disease progression and a lack of human-relevant animal models. An important advance has been made within the past several years, as several genome-wide association studies have discovered that an SNP near the gene encoding membrane-bound O-acyltransferase 7 (MBOAT7) is associated with severe liver diseases. This common MBOAT7 variant (rs641738, C>T), which reduces MBOAT7 expression, confers increased susceptibility to nonalcoholic fatty liver disease, alcohol-associated liver disease, and liver fibrosis in patients chronically infected with viral hepatitis. Recent studies in mice also show that Mboat7 loss of function can promote hepatic steatosis, inflammation, and fibrosis, causally linking this phosphatidylinositol remodeling enzyme to liver health in both rodents and humans. Herein, we review recent insights into the mechanisms by which MBOAT7-driven phosphatidylinositol remodeling influences liver disease progression and discuss how rapid progress in this area could inform drug discovery moving forward.