Human leukocyte antigen-G in hepatocellular carcinoma driven by chronic viral hepatitis or steatotic liver disease

Abstract

Hepatocellular carcinoma (HCC) is the sixth most common cancer globally and the third leading cause of cancer-related mortality, primarily driven by viral infections (HCV, HBV) and steatotic liver diseases (SLD). Despite advances in treatment, early detection and accurate prognosis remain challenging. The Human leukocyte antigen G (HLA-G) molecule is dysregulated in various conditions, including cancers and viral infections. This study aimed to investigate HLA-G's role in viral-related and SLD-driven HCC. We analyzed a cohort of 116 HCC patients and 140 healthy controls to assess HLA-G genetic variants and soluble levels. Results showed significantly higher levels of soluble HLA-G in HCC patients compared to controls (Pc = 0.003). Moreover, overall survival (OS) was significantly lower in patients with the extended HLA-G*01:01:01/UTR-1 haplotype (Log-rank test, p = 0.002), a trend consistent in both HCV and/or HBV-related HCC (p = 0.025) and SLD-related HCC (p = 0.018). Elevated sHLA-G levels were associated with shorter OS across both subgroups (p = 0.034 (HBV/HCV) and p = 0.010 (SLD), respectively). The findings suggest that elevated levels of soluble HLA-G and specific genetic variants are associated with poor prognosis in HCC patients, highlighting the potential of HLA-G as a prognostic biomarker in both viral-related and steatotic liver disease-related HCC.

Keywords: CC; HBV; HCV; HLA-G; SLD; sHLA-G.

Fig. 1

HCC Patients’ enrollment. A total of 132 HCC patients were recruited between 2017 and 2022 and were followed at the Liver Unit of the University Hospital and the Division of Gastroenterology at ARNAS G. Brotzu (Cagliari, Italy). HCC was diagnosed according to the American Association for the Study of Liver Diseases (AASLD) guidelines. The aim of the study was to evaluate the influence of extended HLA-G haplotypes and their associated sHLA-G levels on the onset and progression of HCC, and to investigate potential differences between two subgroups of patients: i) HCC driven by viral hepatitis (HBV and/or HCV) and ii) HCC associated with SLD (ALD or MASLD/MASH). For this reason, 6 patients were excluded from the initial cohort of 132 as their HCC had developed due to autoimmune hepatitis type 1 (n = 2), hemochromatosis (n = 2), Wilson’s disease (n = 1), or cryptogenic SLD (n = 1). An additional 10 patients were excluded due to the absence of plasma samples at diagnosis or incomplete clinical and follow-up data. AIH-1: Autoimmune Hepatitis type 1; HFE: Hereditary Hemochromatosis; WD: Wilson’s Disease; SLD: Steatotic Liver Disease; HBV: Hepatitis B Virus; HCV: Hepatitis C Virus; ALD: Alcoholic Liver Disease; MASLD: Metabolic Dysfunction Associated Steatotic Liver Disease; MASH: Metabolic Dysfunction Associated Steatohepatitis. Note: New fatty liver disease nomenclature as defined in a multisociety Delphi consensus statement.

Fig. 2

Soluble HLA-G (sHLA-G) plasma levels (U/mL) were compared between HCC patients and the control group (A), and in the two groups of HCC patients (SLD vs HBV/HCV and vs Controls) (B). The boxplot is included in the violin to assess the median and interquartile range. The vertical bars represent the 95% confidence intervals. P values and mean differences, were obtained by the Student’s t test. * Median and Pc value if the HLA-G levels greater than 100 U/ml are excluded.

Fig. 3

HCC Overall Survival based on HLA-G extended haplotypes. The overall survival (OS) of HCC-specific mortality is graphically presented for a cohort of 116 patients observed over a 60-months time frame. Patients were categorized based on their HLA-G extended haplotypes (HLA-G alleles with 3’UTR) in HLA-G*01:01:01/UTR-1 homozygous, HLA-G*01:01:01/UTR-1 heterozygous or HLA-G other extended haplotypes (HLA-G alleles with their UTR). P-values were calculated using the two-sided log-rank test. A) Overall Survival based on HLA-G extended haplotypes in patients with HCC related to HCV and/or HBV infection. The overall survival (OS) of HCC-specific mortality is graphically presented for a cohort of 95 patients observed over a 60-months time frame. Patients were categorized based on their HLA-G extended haplotypes (HLA-G alleles with 3’UTR) in HLA-G*01:01:01/UTR-1 homozygous, HLA-G*01:01:01/UTR-1 heterozygous or HLA-G other extended haplotypes (HLA-G alleles with their UTR). P-values were calculated using the two-sided log-rank test. B) Overall Survival based on HLA-G extended haplotypes in patients with HCC SLD related. The overall survival (OS) of HCC-specific mortality is graphically presented for a cohort of 21 patients observed over a 60-months time frame. Patients were categorized based on their HLA-G extended haplotypes (HLA-G alleles with 3’UTR) in HLA-G*01:01:01/UTR-1 homozygous, HLA-G*01:01:01/UTR-1 heterozygous or HLA-G other extended haplotypes (HLA-G alleles with their UTR). P-values were calculated using the two-sided log-rank test. This HCC patients subgroup included ALD and MASLD/MASH. Abbreviations: SLD = Steatotic liver disease; ALD = Alcoholic liver disease; MASLD = Metabolic dysfunction associated with steatotic liver disease; MASH = Metabolic dysfunction associated with steatohepatitis.

Fig. 4

HCC Overall Survival based on sHLA-G levels. The overall survival of HCC-specific mortality is graphically presented for a cohort of 116 patients observed over a 60-months time frame. Patients were categorized based on their soluble HLA-G (sHLA-G) in low (< 25 U/mL) medium (25–80 U/mL) or high (> 80 U/mL) levels. P-values were calculated using the two-sided log-rank test. A) Overall Survival based on sHLA-G levels in patients with HCC related to HCV and/or HBV infection The overall survival (OS) of HCC-specific mortality is graphically presented for a cohort of 95 patients observed over a 60-months time frame. Patients were categorized based on their soluble HLA-G (sHLA-G) in low (< 25 U/mL) medium (25–80 U/mL) or high (> 80 U/mL) levels. P-values were calculated using the two-sided log-rank test. B) Overall Survival based on sHLA-G levels in patients with HCC SLD related The overall survival (OS) of HCC-specific mortality is graphically presented for a cohort of 21 patients observed over a 60-months time frame. Patients were categorized based on their soluble HLA-G (sHLA-G) in low (< 25 U/mL) medium (25–80 U/mL) or high (> 80 U/mL) levels. P-values were calculated using the two-sided log-rank test. This HCC patients subgroup included ALD and MASLD/MASH. Abbreviations: SLD = Steatotic liver disease; ALD = Alcoholic liver 330 disease; MASLD = Metabolic dysfunction associated steatotic liver disease; MASH = Metabolic dysfunction associated steatohepatitis.