Background: Cancer‐associated fibroblasts (CAFs) play an important role in the induction of chemo‐resistance. This study aimed to clarify the mechanism underlying CAF‐mediated resistance to two tyrosine kinase inhibitors (TKIs), sorafenib and lenvatinib, and to identify a novel therapeutic target for overcoming TKI resistance in hepatocellular carcinoma (HCC). Methods: We performed a systematic integrative analysis of publicly available gene expression datasets and whole‐transcriptome sequencing data from 9 pairs of CAFs and para‐cancer fibroblasts isolated from human HCC and para‐tumor tissues, respectively, to identify key molecules that might induce resistance to TKIs. We then performed in vitro and in vivo experiments to validate selected targets and related mechanisms. The associations of plasma secreted phosphoprotein 1 (SPP1) expression levels before sorafenib/lenvatinib treatment with progression‐free survival (PFS) and overall survival (OS) of 54 patients with advanced HCC were evaluated using Kaplan‐Meier and Cox regression analysis. Results: Bioinformatic analysis identified CAF‐derived SPP1 as a candidate molecule driving TKI resistance. SPP1 inhibitors reversed CAF‐induced TKI resistance in vitro and in vivo. CAF‐derived SPP1 activated rapidly accelerated fibrosarcoma (RAF)/mitogen‐activated protein kinase (MAPK) and phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) through the integrin‐protein kinase C‐alpha (PKCα) signaling pathway and promoted epithelial‐to‐mesenchymal transition (EMT). A high plasma SPP1 level before TKI treatment was identified as an independent predictor of poor PFS ( P = 0.026) and OS ( P = 0.047) in patients with advanced HCC after TKI treatment. Conclusions: CAF‐derived SPP1 enhances TKI resistance in HCC via bypass activation of oncogenic signals and EMT promotion. Its inhibition represents a promising therapeutic strategy against TKI resistance in HCC. Moreover, plasma SPP1 level before TKI treatment represents a potential biomarker for treatment response prediction.

Hepatocellular carcinoma (HCC) develops almost entirely in the presence of chronic inflammation. Chronic hepatitis B virus (HBV) infection with recurrent immune-mediated liver damage ultimately leads to cirrhosis and HCC. It is widely accepted that HBV infection induces the dysfunction of the innate and adaptive immune responses that engage various immune cells. Natural killer (NK) cells are associated with early antiviral and antitumor properties. On the other hand, inflammatory cells release various cytokines and chemokines that may promote HCC tumorigenesis. Moreover, immunosuppressive cells such as regulatory T cells (Treg) and myeloid-derived suppressive cells play a critical role in hepatocarcinogenesis. HBV-specific CD8+ T cells have been identified as pivotal players in antiviral responses, whilst extremely activated CD8+ T cells induce enormous inflammatory responses, and chronic inflammation can facilitate hepatocarcinogenesis. Controlling and maintaining the balance in the immune system is an important aspect in the management of HBV-related HCC. We conducted a review of the current knowledge on the immunopathogenesis of HBV-induced inflammation and the role of such immune activation in the tumorigenesis of HCC based on the recent studies on innate and adaptive immune cell dysfunction in HBV-related HCC.

Hepatocellular carcinoma (HCC) has a high rate of cancer recurrence (up to 70%) in patients who undergo surgical resection. We investigated prognostic gene signatures for predicting HCC recurrence using in silico gene expression analysis. Recurrence-associated gene candidates were chosen by a comparative analysis of gene expression profiles from two independent whole-transcriptome datasets in patients with HCC who underwent surgical resection. Five promising candidate genes, CETN2, HMGA1, MPZL1, RACGAP1, and SNRPB were identified, and the expression of these genes was evaluated using quantitative reverse transcription PCR in the validation set (n = 57). The genes CETN2, HMGA1, RACGAP1, and SNRPB, but not MPZL1, were upregulated in patients with recurrent HCC. In addition, the combination of HMGA1 and MPZL1 demonstrated the best area under the curve (0.807, 95% confidence interval [CI] = 0.681–0.899) for predicting HCC recurrence. In terms of clinicopathological correlation, CETN2, MPZL1, RACGAP1, and SNRPB were upregulated in patients with microvascular invasion, and the expression of MPZL1 and SNRPB was increased in proportion to the Edmonson tumor differentiation grade. Additionally, overexpression of CETN2, HMGA1, and RACGAP1 correlated with poor overall survival (OS) and disease-free survival (DFS) in the validation set. Finally, Cox regression analysis showed that the expression of serum alpha-fetoprotein and RACGAP1 significantly affected OS, whereas platelet count, microvascular invasion, and HMGA1 expression significantly affected DFS. In conclusion, HMGA1 and RACGAP1 may be potential prognostic biomarkers for predicting the recurrence of HCC after surgical resection.

Hyo Jung Cho, Sunhyuk Hwang , Jong Ik Park, Min Jae Yang, Jae Chul Hwang, Byung Moo Yoo, Kee Myung Lee, Sung Jae Shin, Kwang Jae Lee, Jin Hong Kim, Jae Youn Cheong, Sung Won Cho, and Soon Sun Kim. Gut and Liver 1999;0:. https://doi.org/10.5009/gnl18382

This study investigated the diagnostic potential of serum small extracellular vesicle‐derived long noncoding RNAs (EV‐lncRNAs) for hepatocellular carcinoma (HCC). Driver oncogenic lncRNA candidates were selected by a comparative analysis of lncRNA expression profiles from two whole transcriptome human HCC datasets (Catholic_LIHC and TCGA_LIHC). Expression of selected lncRNAs in serum and small EVs was evaluated using quantitative reverse transcription PCR. Diagnostic power of serum EV‐lncRNAs for HCC was determined in the test (n = 44) and validation (n = 139) cohorts. Of the six promising driver onco‐lncRNAs, DLEU2, HOTTIP, MALAT1, and SNHG1 exhibited favorable performance in the test cohort. In the validation cohort, serum EV‐MALAT1 displayed excellent discriminant ability, while EV‐DLEU2, EV‐HOTTIP, and EV‐SNHG1 showed good discriminant ability between HCC and non‐HCC. Furthermore, a panel combining EV‐MALAT1 and EV‐SNHG1 achieved the best area under the curve (AUC; 0.899, 95% CI = 0.816–0.982) for very early HCC, whereas a panel with EV‐DLEU2 and alpha‐fetoprotein exhibited the best positivity (96%) in very early HCC. Serum small EV‐MALAT1, EV‐DLEU2, EV‐HOTTIP, and EV‐SNHG1 may represent promising diagnostic markers for very early‐stage HCC.