HAVCR2 and neoplasm: Therefore, cluster 2 of CM was considered the hot tumor to respond to immunotherapy because cluster 2 of CM displayed the characteristics of hot immune tumors, such as a high degree of CD8+ T cells, high immune score, more active immune functions, and higher expression of CTLA4, TIM3, and LAG3 (Galon and Bruni, 2019; Zheng et al., 2021).