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BackgroundWe evaluated apparent diffusion coefficient (ADC) of diffusion‐weighted image MRI as a prognostic factor for mass‐forming intrahepatic cholangiocarcinoma (IHCC).MethodsWe enrolled 26 patients who had undergone hepatic resections for mass‐forming‐type IHCC in this study, and calculated their mean ADC, using diffusion‐weighted image MRI (b: 0, 20, 800 seconds/mm2; 1.5 T MRI). Patients were divided into the ADCHigh and the ADCLow groups at the median ADC value (n = 13 for both). We also immunohistochemically evaluated hypoxia‐inducible factor (HIF)‐1α in tumor tissue.ResultsMedian age in the ADCLow was older (P = .03), and showed significant higher rate of scirrhous tumor (P = .02). The 5‐year overall survival rate in the ADCLow group was significantly worse than in the ADCHigh group (P = .04). In multivariate analysis, hilar tumor, portal vein invasion and low ADC were independent prognostic factors (P < .05). The ADCLow group also had a higher rate of high HIF‐1α expression than the ADCHigh group (P < .05). Representative case of ADCLow group showed rich stroma and high HIF‐1α expression.ConclusionsThe ADC values in MRIs can predict IHCC prognosis, and correlated with stromal density and HIF‐1α expression.

Background: Cancer-tumor associated macrophage (TAM)-cancer associated fibroblast (CAF) interactions are an important factor in the tumor microenvironment of hepatocellular carcinoma. Materials and Methods: Hepatic stellate cells (HSCs) were cultured with cancer cell-conditioned medium (Ca.-CM), TAM-CM and CAF-CM, and the expression of CAF markers were evaluated by RT-PCR. Whether HSCs cultured with Ca.-CM, TAM-CM and CAF-CM contributed to the enhanced malignancy of cancer cells was examined using proliferation, invasion and migration assays. Furthermore, the differences between these three types of CM were evaluated using cytokine arrays. Results: HSCs cultured with Ca.-CM, TAM-CM and CAF-CM showed significantly increased mRNA expression of αSMA, FAP and IL-6. All HSCs cultured with each CM exhibited significantly increased proliferation, invasion and migration of cancer cells. The osteopontin concentration was significantly higher in HSCs cultured with TAM-CM than the other CAF-CMs. Osteopontin inhibition significantly reduced osteopontin secretion from HSCs cultured with TAM-CM and suppressed the proliferation and invasion of cancer cells enhanced by HSCs cultured with TAM-CM. Conclusions: We observed enhanced osteopontin secretion from TAMs, and this increased osteopontin further promoted osteopontin secretion from HSCs cultured with TAM-CM, leading to increased malignancy. For the first time, we demonstrated the importance of cancer-TAM-CAF interactions via osteopontin in hepatocellular carcinoma.

Background and aim As a multiple tyrosine kinase inhibitor, sorafenib is widely used to treat hepatocellular carcinoma (HCC), but patients frequently face resistance problems. Because the mechanism controlling sorafenib-resistance is not well understood, this study focused on the connection between tumor characteristics and the Nrf2 signaling pathway in a sorafenib-resistant HCC cell line. Methods A sorafenib-resistant HCC cell line (Huh7) was developed by increasing the dose of sorafenib in the culture medium until the target concentration was reached. Cell morphology, migration/invasion rates, and expression of stemness-related and ATP-binding cassette (ABC) transporter genes were compared between sorafenib-resistant Huh7 cells and parental Huh7 cells. Next, a small interfering RNA was used to knock down Nrf2 expression in sorafenib-resistant Huh7 cells, after which cell viability, stemness, migration, and ABC transporter gene expression were examined again. Results Proliferation, migration, and invasion rates of sorafenib-resistant Huh7 cells were significantly increased relative to the parental cells with or without sorafenib added to the medium. The expression levels of stemness markers and ABC transporter genes were up-regulated in sorafenib-resistant cells. After Nrf2 was knocked down in sorafenib-resistant cells, cell migration and invasion rates were reduced, and expression levels of stemness markers and ABC transporter genes were reduced. Conclusion Nrf2 signaling promotes cancer stemness, migration, and expression of ABC transporter genes in sorafenib-resistant HCC cells.

The tumor microenvironment affects malignancy in hepatocellular carcinoma (HCC) cells, and cancer‐associated fibroblasts (CAFs) play an important role in the microenvironment. As recent studies indicated a difference between CAFs isolated from chemoresistant and non‐resistant cancer tissues, therefore we investigated the intracellular mechanism in resistant HCC co‐cultured CAFs and interactions between these CAFs with cancer cells. We established a sorafenib‐resistant (SR) Huh7 (human HCC) cell line, and characterized it with cytokine assays, then developed CAFs by co‐culturing human hepatic stellate cells with resistant or parental Huh7 cells. The 2 types of CAFs were co‐cultured with parental Huh7 cells, thereafter the cell viability of these Huh7 cells was checked under sorafenib treatment. The SR Huh7 (Huh7SR) cells expressed increased B‐cell activating factor (BAFF), which promoted high expression of CAF‐specific markers in Huh7SR‐co‐cultured CAFs, showed activated BAFF, BAFF‐R, and downstream of the NFκB‐Nrf2 pathway, and aggravated invasion, migration, and drug resistance in co‐cultured Huh7 cells. When we knocked down BAFF expression in Huh7SR cells, the previously increased malignancy and BAFF/NFκB axis in Huh7SR‐co‐cultured CAFs reversed, and enhanced chemoresistance in co‐cultured Huh7 cells returned as well. In conclusion, the BAFF/NFκB pathway was activated in CAFs co‐cultured with cell‐culture medium from resistant Huh7, which promoted chemoresistance, and increased the malignancy in co‐cultured non‐resistant Huh7 cells. This suggests that the BAFF/NFκB axis in CAFs might be a potential therapeutic target in chemoresistance of HCC.