INS and cancer: In contrast to a transient retention of this metabolic asymmetry without stress and insulin deficit in pregnancy, the chronic retention of such an asymmetry with stress and insulin deficit between cancer and host cells might trigger formation of a vicious cycle (Figures 2, 3); its action is supported by cancer-induced activation of the complex catabolic programs (such as inflammation, stress, and lipolysis) resulting in subversion of the systemic glucose metabolism.