How have researchers targeted cancer cells lacking a key DNA repair protein?

Researchers have focused on inhibiting alternative DNA repair mechanisms in cancer cells that lack a key DNA repair protein as a strategic therapeutic approach. The rationale behind this method is based on the concept of "synthetic lethality." In cancer cells deficient in certain DNA repair proteins, alternative repair pathways may become upregulated as a compensatory mechanism to continue repairing DNA and allowing the cancerous cells to survive.

By inhibiting these alternative DNA repair mechanisms, researchers can selectively target the cancer cells that are already compromised in their primary DNA repair capabilities. This results in a greater accumulation of DNA damage specifically in the cancer cells, ultimately leading to cell death while sparing normal cells, which are less reliant on those alternative pathways. This is a promising area of research, as it leverages the vulnerabilities of cancer cells to enhance treatment efficacy and reduce collateral damage to healthy cells.

The other options do not directly apply to the strategy of targeting these cancer cells. For instance, promoting alternative mechanisms or enhancing genetic stability would generally support the survival of cancer cells, not inhibit it. Preventing mitotic division may affect the proliferation of cancer cells but does not specifically address the deficiencies in DNA repair that lead to their survival.