Future studies in the titration of HK1 protein levels using genetic manipulation approaches, such as inducible knockdown of HK1 in HK1+HK2+ cancer cells with different concentrations of doxycycline or inducible expression of HK1 in HK1−HK2+ cancer cells with different concentrations of doxycycline, would quantify the threshold effect of HK1 required to provide resistance to HK2 inhibition in cancer cells. Here, HK1 is linked to cancer.