Functional analysis of the correlation between ABCB11 gene mutation and primary intrahepatic stone

Abstract

The adenosine 5′-triphosphate binding cassette subfamily B member (ABCB)11 gene is involved in bile transport, and mutations in this gene are associated with cholestasis and cholelithiasis. Therefore, the aim of the present study was to investigate the association between ABCB11 gene mutation and primary intrahepatic stone (PIS)s and to investigate the mechanism through which ABCB11 gene mutations affect the expression of the corresponding protein. Mutations of the ABCB11 gene in 443 PIS patients and 560 healthy participants were detected by exon sequencing. The expression levels of ABCB11 mRNA and bile salt export pump (BSEP) protein in the liver tissues of patients with PISs were measured by quantitative polymerase chain reaction and western blot analysis. The mutant plasmids constructed by site-directed mutagenesis of the human BSEP gene were transfected into human embryonic kidney 293 (293) cells and Madin-Darby canine kidney (MDCK) cells, and the expression and distribution of rs118109635 of BSEP was measured. There were two significant mutations in the ABCB11 gene of the PIS patients compared with the healthy population; a missense mutation, rs118109635 (P=0.025), and a synonymous mutation, rs497692 (P=0.006). The two mutations were associated with the occurrence of preoperative jaundice (P=0.026, and P=0.011, respectively). The expression levels of BSEP in PIS patients with the missense mutation rs118109635 was decreased, whereas its mRNA expression levels remained unchanged. In PIS patients with the synonymous mutation rs497692, the expression levels of ABCB11 were decreased at both the mRNA and protein level. It was also found that mutation A865V reduced the expression levels of BSEP in 293 cells at the cellular level; its distribution in MDCK cell membranes was decreased, whereas its mRNA levels remained unchanged. The mutated loci at rs118109635 and rs497692 of the ABCB11 gene were correlated with PISs, causing a decreased expression of BSEP and reduced distribution of the protein in the cell membrane. Therefore, mutations at rs118109635 and rs497692 of the ABCB11 gene may be risk factors for PISs.

S100A8 facilitates cholangiocarcinoma metastasis via upregulation of VEGF through TLR4/NF‑κB pathway activation

“…Immunoblotting analyses were performed as described previously (27). Antibodies against S100A8 (cat.…”

Genetics of Gallstone Disease and Their Clinical Significance: A Narrative Review

“…A significant proportion of these mutations influence cholesterol synthesis or transport in various ways ( Table 1 ). 12 , 14 , 19 , 20 , 23 , 28 , 30 , 31 , 33 – 35 , 37 , 38 , 40 , 47 , 51 , 52 , 66 – 71 Notably, the most impactful genes are those belonging to the ABC transporter family, particularly the ABCG8 cholesterol transporter. Different genes play important roles in the pathogenesis of GS disease across various ethnicities.…”

“…A significant proportion of these mutations influence cholesterol synthesis or transport in various ways (Table 1). 12,14,19,20,23,28,30,31,[33][34][35]37,38,40,47,51,52,[66][67][68][69][70][71] Notably, While cholelithiasis is commonly observed, particularly among older adults, certain features should prompt consideration of a genetic basis for this condition (Fig. 2).…”

“…Furthermore, the research is conducted within a moderately homogenous population, raising questions about the generalizability of the findings. 35 …”

A Recent Ten-Year Perspective: Bile Acid Metabolism and Signaling

“…Missense mutations, synonymous mutations, and deletions of the bile salt exporting pump gene are associated with the development of cholestatic liver diseases, such as benign recurrent intrahepatic cholestasis type 2, progressive familial intrahepatic cholestasis type 2, intrahepatic cholestasis of pregnant women, cholelithiasis, and intrahepatic calculi [ 139 , 140 , 141 , 142 , 143 , 144 ].…”