Mechanisms of Sorafenib Resistance in HCC Culture Relate to the Impaired Membrane Expression of Organic Cation Transporter 1 (OCT1)

Srinivas Chava,1 Nergiz Ekmen,2 Pauline Ferraris,1 Yucel Aydin,2 Krzysztof Moroz,1 Tong Wu,1 Swan N Thung,3 Srikanta Dash1,2,4 1Department of Pathology and Laboratory Medicine, Tulane University Health Sciences Center, New Orleans, LA, USA; 2Department of Gastroenterology and Hepatology, Tulane University Health Sciences Center, New Orleans, LA, USA; 3Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA; 4Southeast Louisiana Veterans Health Care System, New Orleans, LA, USACorrespondence: Srikanta Dash, Department of Pathology and Laboratory Medicine, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA, 70112, USA, Tel +1 504-988-2519, Fax +1 504-988-7389, Email [email protected]: Sorafenib, an FDA-approved drug for advanced hepatocellular carcinoma (HCC) treatment, encounters resistance in many patients. Deciphering the mechanisms underlying sorafenib resistance is crucial for devising alternative strategies to overcome it.Aim: This study aimed to investigate sorafenib resistance mechanisms using a diverse panel of HCC cell lines.Methods: HCC cell lines were subjected to continuous sorafenib treatment, and stable cell lines (Huh 7.5 and Huh 7PX) exhibiting sustained growth in its presence were isolated. The investigation of drug resistance mechanisms involved a comparative analysis of drug-targeted signal transduction pathways (EGFR/RAF/MEK/ERK/Cyclin D), sorafenib uptake, and membrane expression of the drug uptake transporter.Results: HCC cell lines (Huh 7.5 and Huh 7PX) with a higher IC50 (10μM) displayed a more frequent development of sorafenib resistance compared to those with a lower IC50 (2– 4.8μM), indicating a potential impact of IC50 variation on initial treatment response. Our findings reveal that activated overexpression of Raf1 kinases and impaired sorafenib uptake, mediated by reduced membrane expression of organic cation transporter-1 (OCT1), contribute to sorafenib resistance in HCC cultures. Stable expression of the drug transporter OCT1 through cDNA transfection or adenoviral delivery of OCT1 mRNA increased sorafenib uptake and successfully overcame sorafenib resistance. Additionally, consistent with sorafenib resistance in HCC cultures, cirrhotic liver-associated human HCC tumors often exhibited impaired membrane expression of OCT1 and OCT3.Conclusion: Intrinsic differences among HCC cell clones, affecting sorafenib sensitivity at the expression level of Raf kinases, drug uptake, and OCT1 transporters, were identified. This study underscores the potential of HCC tumor targeted OCT1 expression to enhance sorafenib treatment response.Keywords: hepatocellular carcinoma, HCC, cholangiocarcinoma, CCA, tyrosine kinase inhibitors, TKI, organic cation transporter-1, OCT1, organic cation transporter-3, OCT3, sorafenib resistance cell lines, SR huh

The Medical Genome Reference Bank contains whole genome and phenotype data of 2570 healthy elderly

Population health research is increasingly focused on the genetic determinants of healthy ageing, but there is no public resource of whole genome sequences and phenotype data from healthy elderly individuals. Here we describe the first release of the Medical Genome Reference Bank (MGRB), comprising whole genome sequence and phenotype of 2570 elderly Australians depleted for cancer, cardiovascular disease, and dementia. We analyse the MGRB for single-nucleotide, indel and structural variation in the nuclear and mitochondrial genomes. MGRB individuals have fewer disease-associated common and rare germline variants, relative to both cancer cases and the gnomAD and UK Biobank cohorts, consistent with risk depletion. Age-related somatic changes are correlated with grip strength in men, suggesting blood-derived whole genomes may also provide a biologic measure of age-related functional deterioration. The MGRB provides a broadly applicable reference cohort for clinical genetics and genomic association studies, and for understanding the genetics of healthy ageing

Hepatic Stellate Cell Immunodetection and Cirrhotic Evolution of Viral Hepatitis in Liver Allografts.

Patients with chronic viral hepatitis are at high risk of developing cirrhosis, but the outcome of the disease in a given patient is unpredictable. Hepatic stellate cells have been demonstrated to be the most important cell type involved in hepatic fibrogenesis, regardless of the cause of the liver injury. The alpha isotype of actin (a phenotypic marker of smooth muscle cells) may be expressed by hepatic stellate cells, reflecting their "activation" to myofibroblast-like cells. The present study aimed to analyze the expression of alpha-smooth muscle actin-positive hepatic stellate cells in liver allografts with recurrent viral hepatitis, and to evaluate whether and how such expression may be related to the outcome of the disease. Using immunohistochemistry and a semi-quantitative scoring system, the expression of a-smooth muscle actin in hepatic stellate cells was analyzed in liver allografts of 17 patients with recurrent viral hepatitis. They included nine patients who developed cirrhosis at the end of follow-up (mean time 23.6 months), and eight patients with no cirrhosis at the end of a comparable follow-up time (mean 30.1 months). In all patients, liver biopsy specimens were obtained between 3 and 6 months (t1) and between 10 and 15 months (t2) after transplantation. Preperfusion biopsy specimens of donor livers served as a baseline (t0). By comparison with the baseline biopsy, an increased number of alpha-smooth muscle actin-expressing hepatic stellate cells was observed in all cases in t1 biopsies. An increase in the amount of alpha-smooth muscle actin-positive hepatic stellate cells in zone 1 at t1 was significantly (P < .006) related to subsequent cirrhotic evolution. In conclusion, in liver allografts with recurrent viral hepatitis, the activation of hepatic stellate cells is an early event. An increased number of alpha-smooth muscle actin-positive hepatic stellate cells in zone 1 may represent an unfavorable event related to cirrhotic evolution

Hepatic stellate cell immunodetection and cirrhotic evolution of viral hepatitis in liver allografts

Abstract Patients with chronic viral hepatitis are at high risk of developing cirrhosis, but the outcome of the disease in a given patient is unpredictable. Hepatic stellate cells have been demonstrated to be the most important cell type involved in hepatic fibrogenesis, regardless of the cause of the liver injury. The alpha isotype of actin (a phenotypic marker of smooth muscle cells) may be expressed by hepatic stellate cells, reflecting their "activation" to myofibroblast-like cells. The present study aimed to analyze the expression of alpha-smooth muscle actin-positive hepatic stellate cells in liver allografts with recurrent viral hepatitis, and to evaluate whether and how such expression may be related to the outcome of the disease. Using immunohistochemistry and a semi-quantitative scoring system, the expression of a-smooth muscle actin in hepatic stellate cells was analyzed in liver allografts of 17 patients with recurrent viral hepatitis. They included nine patients who developed cirrhosis at the end of follow-up (mean time 23.6 months), and eight patients with no cirrhosis at the end of a comparable follow-up time (mean 30.1 months). In all patients, liver biopsy specimens were obtained between 3 and 6 months (t1) and between 10 and 15 months (t2) after transplantation. Preperfusion biopsy specimens of donor livers served as a baseline (t0). By comparison with the baseline biopsy, an increased number of alpha-smooth muscle actin-expressing hepatic stellate cells was observed in all cases in t1 biopsies. An increase in the amount of alpha-smooth muscle actin-positive hepatic stellate cells in zone 1 at t1 was significantly (P < .006) related to subsequent cirrhotic evolution. In conclusion, in liver allografts with recurrent viral hepatitis, the activation of hepatic stellate cells is an early event. An increased number of alpha-smooth muscle actin-positive hepatic stellate cells in zone 1 may represent an unfavorable event related to cirrhotic evolution

Coexistence of hereditary hemorrhagic telangiectasia and fibropolycystic liver disease

This is a case report of a 43-year-old woman who received a transplant for end-stage liver disease due to hereditary hemorrhagic telangiectasia and fibropolycystic liver disease. This is an uncommon association of two autosomal-dominant conditions with defined genetic and molecular defects. The liver showed extensive vascular malformations of arteries and veins as well as telangiectasia and fibrosis. In addition, there were cystically dilated ducts containing inspissated bile and extensive von Meyenburg complexes. This case raises interesting questions about the possible relationship of these genes and their gene products, both of which are related to cell-matrix interactions and an strongly associated with blood vessels, one of them being expressed on endothelial cells and the other being developmentally important in blood vessels