Pan-Cancer Analysis of the Prognostic and Immunological Role of HCCS: A Potential Target for Survival and Immunotherapy

Abstract Background: Holocytochrome c synthase (HCCS) is a cytochrome c synthase that connects heme to cytochrome c. At present, the role of HCCS in tumors have not been reported. Methods: The TIMER2, UALCAN, and HPA databases were also used to explore the expression level of HCCS, the GEPIA2 database was utilized to investigate the relationship between HCCS and the prognosis of patients with tumor, and the TISIDB website was utilized to study the relationship between HCCS and molecular subtypes and immune subtypes. R 3.6.2 software was used to construct ROC curves, DAVID database was used to perform GO and KEGG annotations. Results: We find that HCCS is differentially expressed in 8 types of tumors, high expression of HCCS was correlated with poor prognosis in 5 types of tumors and good prognosis in 3 types of tumors. HCCS is differentially expressed in various molecular subtypes of 14 tumors and various immune subtypes of 19 tumors. HCCS has potential value for the diagnosis estimation of 12 types of tumors. HCCS may be involved in multiple processes, such as organelle fission, chromosome segregation and cell cycle. Silencing HCCS significantly inhibits LAUD cell proliferation, promotes G2M cell cycle arrest, and cisplatin induced cell apoptosis. HCCS is associated with the expression of PD-L1 and immunotherapeutic efficacy in several tumors. Conclusions: This study suggests that HCCS is a biomarker for the diagnosis and prognosis estimation of various tumors, and it may also affect the efficacy of immunotherapy for tumors.