Isolation and characterization of cancer-associated fibroblasts in the tumor microenvironment of hepatocellular carcinoma

Abstract

Background/Aim: Cancer-associated fibroblasts (CAFs) play an immunosuppressive role in the tumor microenvironment (TME) of human cancers; however, their characteristics and role in hepatocellular carcinoma (HCC) remain to be elucidated.Methods: Nine tumor and surrounding liver tissue samples from patients with HCC who underwent surgery were used to isolate patient-derived CAFs. Cell morphology was observed using an optical microscope after culture, and cell phenotypes were evaluated using flow cytometry and immunoblotting. Cytokines secreted by CAFs into culture medium were quantified using a multiplex cytokine assay.Results: CAFs were abundant in the TME of HCC and were adjacent to immune cells. After culture, the CAFs and non-tumor fibroblasts exhibited spindle shapes. We observed a robust expression of alpha-smooth muscle actin and fibroblast activation protein in CAFs, whereas alpha-fetoprotein, epithelial cell adhesion molecule, platelet/endothelial cell adhesion molecule-1, and E-cadherin were not expressed in CAFs. Furthermore, CAFs showed high secretion of various cytokines, namely C-X-C motif chemokine ligand 12, interleukin (IL)-6, IL-8, and C-C motif chemokine ligand 2.Conclusions: CAFs are abundant in the TME of HCC and play a crucial role in tumor progression. These fibroblasts secrete cytokines that promote tumor growth and metastasis.

Machine learning model reveals roles of interferon‑stimulated genes in sorafenib‑resistant liver cancer

“…For an edge to be included in the patient-specific gene network, it had to satisfy at least one of two conditions: ( 1 ) at least one gene from a gene pair connected by an edge exhibited a mutation, and the mutational status utilized information specific to individual patients; ( 2 ) the expression of two connected genes aligned with the overall expression pattern observed in the entire cancer sample. To determine this, the RANSAC algorithm was executed 10 times to generate 10 regression models.…”

“…The initial value matrix IM 0 is a diagonal matrix in which the values of the diagonal components are all 10,000, and the impact matrix at τ + 1 is calculated as the product of the stochastic matrix W and the impact matrix at τ . If Equation ( 2 ) is repeated, each column of IM 0 is a one-hot vector whose value exists only in the component of the corresponding column index; therefore, the initial value of each column spreads to other components along the patient-specific gene network. Iteration of Equation ( 2 ) ends when the impact matrix converges.…”

“…If Equation ( 2 ) is repeated, each column of IM 0 is a one-hot vector whose value exists only in the component of the corresponding column index; therefore, the initial value of each column spreads to other components along the patient-specific gene network. Iteration of Equation ( 2 ) ends when the impact matrix converges.…”

“…HCC is the most common form of liver cancer and the fourth leading cause of mortality worldwide ( 1 , 2 ). It predominates as the most common form of liver cancer, representing approximately 90% of all cases ( 3 ).…”