The phenanthrene derivative PJ34 exclusively eradicates human pancreatic cancer cells in xenografts

Exclusive modifications of NuMA in malignant epithelial cells: A potential therapeutic mechanism

NuMA (nuclear mitotic apparatus) protein is indispensable in the mitosis of human proliferating cells, both malignant and benign. The progression of mitosis requires stable spindles, which depend on the bipolar clustering of NuMA within the spindles. The phenanthridine PJ34 kills malignant epithelial cells during mitosis and targets NuMA. PJ34 exclusively blocks the post-translational modification of NuMA in a variety of malignant epithelial cells, but not in benign cells. This blockage of the post-translational modification of NuMA affects its protein-binding capacity and causes construction faults in the mitotic spindle poles of PJ34-treated cancer cells, leading to mitotic catastrophe cell death. PJ34 is a potent PARP1 inhibitor, so its cytotoxicity in human malignant cells is exclusively independent of PARP, challenging the currently accepted notion that inhibition of PARP1 halts cancer by preventing DNA repair. Certain molecules that act as PARP1 inhibitors target other proteins and vital mechanisms in human cancer cells.

The Modified Phenanthridine PJ34 Unveils an Exclusive Cell-Death Mechanism in Human Cancer Cells

This overview summarizes recent data disclosing the efficacy of the PARP inhibitor PJ34 in exclusive eradication of a variety of human cancer cells without impairing healthy proliferating cells. Its cytotoxic activity in cancer cells is attributed to the insertion of specific un-repairable anomalies in the structure of their mitotic spindle, leading to mitotic catastrophe cell death. This mechanism paves the way to a new concept of cancer therapy.