Abstract 5128: Identification and characterization of nasopharyngeal carcinoma prognostic subtypes based on a circRNA classifier: Implications of stratified treatment

Accurate risk stratification for patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) is crucial for treatment decisions and prognosis. Here, we introduce a circRNA-based classifier that could improve the prognostic stratification of LA-NPC patients. The circRNAs are identified by microarray profiling, followed by qRT-PCR validation and selection using a machine learning method in the training cohort (n = 170). Based on the proposed classifier, two prognostic-distinctive NPC subtypes are identified, namely the high-risk subtype (subtype H) and low-risk subtype (subtype L), which have significantly different disease-free survival (HR 2.99, 95% CI 1.58-5.67, P < 0.001). Validation in the internal cohort (n = 170) and external cohort (n = 150) yield similar results and the circRNA-based classifier is an independent risk factor of posttreatment relapse. Meanwhile, multiple interdependent features of different subtypes are observed, including relatively higher immune cell infiltration and immune-related pathways activation in subtype L; and predominant stromal, immunosuppressive and tumor-promoting components with moderate immune activation in subtype H. With a less aggressive and more immune-active tumor microenvironment, patients of subtype L could benefit from the addition of induction chemotherapy. In contrast, patients of subtype H, who are vulnerable to chemoresistance, display a strong tendency to benefit from additional immunotherapy. Overall, we define two NPC prognostic subtypes based on a circRNA classifier across multiple cohorts, which exhibit distinct biological ecosystems and suggest opportunities for the personalization of therapeutic regimens. Citation Format: Yelin Liang, Yuheng Zhao, Qian Li, Wei Jiang, Jun Ma, Na Liu, Yingqin Li. Identification and characterization of nasopharyngeal carcinoma prognostic subtypes based on a circRNA classifier: Implications of stratified treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5128.