Lung Cancer: A Classic Example of Tumor Escape and Progression While Providing Opportunities for Immunological Intervention

Table 1

Mechanisms of lung tumor escape.

(1) Antiapoptosis genes
(a) Bcl-2, survivin
(b) Loss of apoptosis effector molecules: caspases, p53 family
(2) Drug resistance genes
(a) Multidrug resistance proteins
(b) CD133
(3) Immunoresistance genes
(a) Soluble factors: PGE, VEGF, TGF-β, Ido-1, arginase
(b) Immunosuppressive cells: Treg and MDSC
(c) Loss of classical MHC and/or gain of nonconventional MHC
(d) Counterattack: Fas ligand and PD-L/B7-H family members
(e) Age and loss of functional immune system