Pan-cancer analysis of plasmacytoma variant translocation 1 and MYC gene expression pattern and survival prediction

Abstract

Objective: To explore the expression levels and survival prediction of plasmacytoma variant translocation 1 (PVT1) and MYC gene in pan-cancer. Methods: The clinic data and RNA-seq data from 31 types of cancer tissues totaling 10 016 cases were retrieved from The Cancer Genome Atlas (TCGA) database, among which 23 types of cancer with adjacent tissues as normal controls. Student t-tests were used to analyze the significant differences of PVT1 or MYC gene expression levels between cancer tissues and corresponding normal controls. Spearman correlation was used to analyze the expression correlation between PVT1 and MYC in 31 types of cancer. The relationship between PVT1 or MYC expression and overall survival of 31 types of cancer patients was depicted by the Kaplan-Meier curve and Cox proportional hazards model. Results: =PVT1 expression was highly expressed in 19 types of cancer(P<0.05) and lowly expressed in 2 types of cancer (P<0.05). MYC expression was significantly upregulated in 7 types of cancer (P<0.05) and downregulated in 6 types of cancer (P<0.05). Expression correlation analysis presented that PVT1 expression was positively correlated with MYC in about 87% (27/31) types of cancer (Rho>0, P<0.01). Finally, survival analysis showed that relatively high expression of PVT1 was significantly associated with shorter overall survival in bladder urothelial carcinoma, breast invasive carcinoma, adrenocortical carcinoma, renal clear cell carcinoma, renal papillary cell carcinoma, lower grade glioma, prostate adenocarcinoma, testicular germ cell tumors and uveal melanoma (log-rank P<0.05). The relatively high expression group of MYC was significantly correlated with shorter overall survival in adrenocortical carcinoma, bladder urothelial carcinoma, cervical squamous cell carcinoma, head and neck squamous cell carcinoma, renal papillary cell carcinoma, ovarian serous cystadenocarcinoma, pancreatic adenocarcinoma and sarcoma (log-rank P<0.05), while was associated with long-time survival in lower grade glioma and rectum adenocarcinoma (log-rank P<0.05). Conclusions: The increased expression of PVT1 in pan-cancer is more prevalent than that of MYC. The positive correlation between PVT1 and MYC indicates a potential regulatory relationship in cancers. Furthermore, the relatively high expression of PVT1 has a poor effect on the overall survival of patients in 9 types of cancer, while the expression level of MYC presents different effects on the overall survival of patients in various cancers.

Keywords

• |plasmacytoma variant translocation 1 gene|myc gene|tumor|survival time