However, with the development of single-cell sequencing technology, researchers have found that HGSOC tumors contain significant levels of TIL, Treg, and CD8 exhausted T cells that are significantly enriched in the ovarian lesion (primary tumor), but the tumor is still progressing malignantly (28–30) T cell exhaustion is a regulatory mechanism that limits the activity and effector function of T cells under chronic antigen stimulation. This evidence concerns the gene CD8A and neoplasm.