Clinical characterization of MYC family proto-oncogene amplification in solid tumors from Chinese patients.

Abstract

e15140 Background: The dysregulation of the MYC family oncogenes ( c-MYC, MYCN and MYCL) play critical roles in tumorigenesis, prognosis and immune escape. MYC inactivation can result in sustained tumour regression and many therapeutic agents that directly target MYC are under development. MYC signaling is associated with tumor cell PD-L1, overall immune cell infiltration. Herein, we explore MYC family proto-oncogene amplification profiles and clinical characterization in chinese solid tumors. Methods: This research comprehensively characterized gene mutations by next-generation sequencing (NGS) in 23990 chinese solid tumors tissues to reveal the prevalence of MYC family proto-oncogene amplification(MYC AMP) and the association with Tumor mutational burden(TMB) and microsatellite instability(MSI). Results: The prevalence of MYC AMP (copy number, CN≥5) in the cohort was 2.1% (504/23,990), in which ovarian cancer (7.6%, 22/289) showed the highest prevalence, followed by breast cancer (6.1%, 26/429), esophagus cancer (5.9%, 17/287). Only one glioma patient(pt) carried co-amplification of MYCN and c-MYC. In 504 MYC AMP pts, c-MYC AMP accounted for 93.7%(472/504), MYCN and MYCL AMP accounted for 6.5%(33/504) in total. The CN was significantly higher in MYCN and MYCL AMP pts than c-MYC AMP pts (22.9 vs 7.6, p < 0.0001). MSI-H showed a lower detection rate in MYC AMP pts other than Non-MYC AMP pts (0% vs 1.2%, p < 0.05). The proportion of TMB-L in MYC AMP pts was similar to Non-MYC AMP pts (90.9% vs. 90.1%, p > 0.05). Conclusions: In totally, 2.1% of chinese solid tumor pts had MYC high level AMP, mainly c-MYC Amp. The CN was higer in MYCN/ MYCL AMP pts than c-MYC AMP pts. In addition, MYC AMP pts tended to have MSS and TMB-L, suggesting that MYC may be a novel target for tumor immunotherapy. MYC inhibitor combines with immunotherapy may be an important direction for the treatment of MYC AMP pts.