Natural killer cells
Natural killer cells (NK) are lymphocytes of the innate immune system
that monitor cell surfaces of autologous cells for an aberrant
expression of major histocompatibility complex class I (MHC I) molecules
and cell stress markers, which play an important role in antitumor
immune responses[72]. The study found that patients with high
expression of NK cells had a greater OS and PFS and NK cells increased
after EGFR-TKIs treatment[73]. For EGFR-TKIs resistant lung cancer,
up regulating ICAM1 can induce drug resistance, and NK92-CD16 cells
combined with the EGFR antibody could reverse the drug
resistance[74]. Another study found that gefitinib greatly enhanced
NK cells cytotoxicity to lung cancer cells with EGFR L858R+T790M
resistance mutation. Gefitinib could block the immune escape by
up-regulating the expression of NKG2D ligands ULBP1, ULBP2, or MICA on
tumor cells and NKG2D on NK cells in the co-culture system[75]. A
combination of EGFR-TKIs and NK cells adoptive immunotherapy may
represent a potentially effective strategy for EGFR-TKIs resistant lung
cancer.