The loss of cell polarity and cancer are two processes are related, although there is no direct evidence to explain this correlation. In stem cells, loss of cell polarity and consequently, the alteration of the division process could produce cells unable to respond to the mechanisms controlling the proliferation and lead to cancer cells. Research by Emmanuel Caussinus and Cayetano Gonzalez has raised two related questions: if the stem cells can become cancerous cells and if this process may be related to loss of polarity.

To answer these questions have been developed in Drosophila melanogaster larval neuroblasts with mutations in genes that control asymmetric cell division (raps, look, numb or pros) and have observed their proliferative capacity after transplanting in the abdomen of adult flies.

The authors of this paper observed that in the period of two weeks, the brain tissue containing the mutant neuroblasts transplanted into the abdomen of the fly, grew more than 100 times its initial size, invaded other tissues and ultimately killing these insects. The tumors produced from stem cells became immortal being able to retransplantation to other flies. Furthermore, these tumors showed typical features of malignant carcinomas such as centrosome abnormalities and genomic instability.This work shows that loss of function in the progeny of stem cells for each of the genes related to control of the division results in hyperproliferation and cancer.