Bioinformatic analysis and in vitro experiments reveal that N-linked glycosylation related genes STT3A, DDOST and TMEM165 participate in the promotion of hepatocellular carcinoma and Its role in immunotherapy

Background: The complex tumor microenvironment of hepatocellular carcinoma (HCC) has led to a low response to immune checkpoints inhibitors (ICIs) and a poor prognosis. PD-L1, as one of the indications for ICIs, is rich in glycosylation modifications, which result in untimely ICIs. Our study constructed a prognostic model based on N-linked glycosylation related genes for predicting the prognosis and the response to ICIs. Methods: The patients in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts were enrolled. The Cox regression was performed to develop a prognostic model and patients were divided into a low-and high-risk subgroup. 21 recurrent HCC patients who received postoperative adjuvant ICIs were recruited and evaluated the response to ICIs. siRNA was used for in vitro validation. Results: 59 N-linked glycosylation related differentially expressed genes were screened from of HCC and normal tissues in the TCGA cohort. The prognostic model was developed with DDOST, STT3A and TMEM165. The risk score could be an independent prognostic factor. Patients in high-risk subgroup showed worse prognosis than patients in low-risk. ssGSEA showed that patients in the low-risk subgroup were more tend to be immune-activated state. Immunohistochemistry studies showed that DDOST, STT3A and TMEM165 are highly expressed in tumor tissues and patients with high risk score correlated with poor progression free survival and worse immunotherapeutic response. Knockdown of the three genes significantly reduce the proliferation of HCC cell lines. Conclusion: In this study, we establish that the risk model based on N-linked glycosylation related genes could efficiently predict the prognosis and tumor microenvironment immune state of HCC patients, and the risk score could serve as an indicator of ICIs.