Researchers discover an anti-tumor gene loss in cancer of small cell lung

Lung cancer small cell is a special type within the tumors that appear in these organs, and constitutes 15% of the same. It appears almost exclusively in smokers and usually debutes in the stage of disseminated disease, that is, in presence of metastases. It is characterized by initially respond well to chemotherapy, but after one year the tumor recurs and the survival rate decreases.

Compared to other types of lung cancer, non-small cell has not a molecular personalized treatment, in part because of the difficulty of obtaining biological material for study. Today, an article published in Cancer Research, the official journal of the American Association for Cancer Research (AACR), led by Manel Esteller, director of the Program Epigenetics and Cancer Biology of the Bellvitge Biomedical Research Institute, (IDIBELL), ICREA researcher and Professor of Genetics at the University of Barcelona, provides a new genetic alteration in this type of lung cancer that would be a good candidate for the development of specific drugs.

"Our cells have two copies of each gene. And we discovered that 10% of tumors of small cell lung loses both copies of an anti-cancer gene called KAT6B" says Manel Esteller, director of the study.

"The identified gene produces a protein that is a histone acetyltransferase, we can imagine is like a key that unlocks our DNA and other tumor suppressor genes are expressed. When KAT6B lacks in a cell, its DNA is closed on itself and leaves no express these protective genes, accelerating the tumor process "says Esteller and concludes:" Luckily, it seems that these tumor cells that lack this gene would be more sensitive to a drug called irinotecan acting at the DNA level. We would like to see now that patients with this disorder are also more sensitive to this compound in future clinical trials. "

Article reference

Simo-Riudalbas L, Perez-Salvia M, Setien F, Villanueva A, Moutinho C, Martinez-Cardus A, Moran S, Berdasco M, Gomez A, Vidal E, Soler M, Heyn H, Vaquero A, de la Torre C, Barcelo-Batllori S, Vidal A, Roz L, Pastorino U, Szakszon K, Borck G, Moura C, Carneiro F, Zondervan I, Savola S, Iwakawa R, Kohno T, Yokota J, Esteller M. KAT6B is a tumor suppressor histone H3 lysine 23 acetyltransferase undergoing genomic loss in small cell lung cancer. Cancer Research, pii: canres.3702.2014, 2015.

Image: Cells containing the normal two copies of the gene (green dots); Right image, small cell lung cancer which has lost both copies of the protective gene cancer. In red the normal two copies of a gene control experiment shown.