Because B7S1 expressed by tumor-infiltrating myeloid cells has been reported to induce dysfunction of antitumor CD8+ T cells in liver cancer (Li et al., 2018), the expression patterns of B7S1 and pB7S1R strongly suggested that B7S1 expression in OvCa may inhibit CD8+ T cell function. The gene discussed is CD8A; the disease is liver cancer.