Small-molecule inhibition of general transcriptional regulators in cancer

Abstract

Transcription is frequently deregulated in cancer, but targeting of transcriptional processes for cancer therapy has thus far been limited to nuclear receptors. Recent studies, however, have suggested that inhibitors of various general transcriptional regulators can be used in cancer therapy because expression of some oncogenes is disproportionately sensitivity to these inhibitors. Here, I describe the cellular and molecular effects of inhibiting a general transcriptional regulator, CDK7, in T-cell acute lymphoblastic leukemia (T-ALL) cells. Because tumor cells commonly evolve resistance to individual therapies, I have also investigated the potentially synergistic effects of combining two compounds that target transcriptional regulators - the CDK7-inhibitor THZ1 and the BRD4-inhibitor JQ1 - and suggest a model describing the molecular basis of the synergistic effects I observed. My research provides insight into the effects of these inhibitors of general transcriptional regulators on tumor cell behavior and gene expression programs.