CD4 and neoplasm: The anticancer effects of kefir may stem from its ability to activate a series of apoptotic pathways (Bcl2↓, bax, caspase3↑) and tumor signaling inhibitory pathways (p53, p21, p27↑), as well as to induce immune enhancement, such as upregulation of CD4+ T and CD8+ T cells (El-Din et al., 2020).