HCP5 and prostate cancer: Liang et al. (2018) confirm that HCP5 promotes thyroid follicular carcinoma progression through miRNAs sponge. And HCP5 can also act as a sponge of miR-4656, performing regulation of CEMIP and promotion of proliferation of prostate cancer cells (Hu and Lu, 2020). However, the role and mechanism of HCP5 in GC under hypoxia have not been studied. Therefore, we investigated the function of HCP5 in GC based on the in vitro cell culture under hypoxia, with the goal to discover a novel diagnostic biomarker and a new treatment target.