Portal vein tumor thrombus is more sensitive to irradiation

Purpose: To study the changes of biological behavior in PVTT cells after irradiation. Methods: PVTToriginated cells CSQT-2 were compared with the HL-7702 human liver cell line, Hep3B and Huh7 human HCC cell lines on irradiation biology parameters and irradiation-related biological behavior, including apoptosis, proliferation and metastasis and other related mechanisms in vitro. We further assessed the radiosensitivity of xenograft in vivo. Results: Irradiation biology parameters of CSQT-2 cell were less than that of HCC cells; irradiated CSQT-2 cells had a higher prevalence of apoptosis and death, a higher rate of proliferation inhibition, and a weakened migration capacity compared with HCC cell lines. In addition, CSQT-2 cells had a higher rate of activated apoptotic proteins which arrested cell cycles in the G2/M phase, including PARP and caspase3, and a decreased rate of PCNA expression. Importantly, irradiation induced more severe shrinkage in the xenograft tumor derived from CSQT-2 cells compared with derived from Huh7 cells. Conclusions: Our results demonstrated that PVTT-originated cells were more radiosensitive than HCC cells both in vitro and in vivo, which supported the application of radiotherapy for HCC patients with PVTT in clinical settings.