They discover a bacterial mechanism that could destroy tumor cells

Salamanca (Spain).- An international study led by the Cancer Research Center (CIC), a joint center of the CSIC and the University of Salamanca of Spain, has identified a mechanism by which a protein secreted by the bacterium 'vibrio cholerae' is capable of destroying cancer cells. The research, published in Cell Death Discovery and opening the door to new treatments, has tested the discovered mechanism in human tumor cells of the breast, colon, and pancreas.

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The HapA protein, produced by the bacterium 'vibrio cholerae', acts as a kind of 'key' capable of locating specific 'locks' (called PAR-1 and PAR-2 receptors) found on the surface of tumor cells and, by opening those locks, triggers a chain reaction within the cells that leads them to self-destruct. The scientific team used both the original bacterial culture and artificially modified harmless bacteria to produce only HapA, and thus it was demonstrated that the effect was indeed caused by this specific protein and not by other possible factors of the bacteria. "This work demonstrates the potential of bacterial proteins as antitumor therapeutic tools. The selective action and intracellular activation mode open up new perspectives for developing combined and specific treatments," highlighted the Spanish CSIC researcher at the CIC, Antonio Hurtado.

A precise methodology

To develop this study, the bacterium 'vibrio cholerae' was cultivated, using a normal strain and another genetically modified mutant, and subsequently 'supernatant' was collected, which is the liquid where these bacteria grow and which also contains the proteins and substances released by the bacteria, and it was applied to human cancerous cells of the colon, breast, and pancreas to observe what effects it produced. "What we sought was to verify if human cells from different tumor types (breast, colon, and pancreas) remained alive and if they could multiply after being in contact with these bacterial substances, particularly with the HapA protein," Hurtado explained. In the research, they have used advanced real-time imaging systems that allow them to count living and dead cells, and measure apoptosis (programmed death) to accurately observe the blocking of pathways.