Loss of micro-RNA may trigger malignant growth in lung cancer cells
Micro-RNA plays an important role in the malignancy of lung cancer, according to a study published in Molecular Cancer Research (2010 Sep;8(9):1207-16).
Led by Heike Allgayer, medical researcher and head of a clinical cooperation unit of DKFZ and UMM, a team of researchers studied various cell lines of non-small cell lung cancer to investigate miR-200c and its role in malignant growth. They discovered that the less miR-200c is produced by a cell line, the higher its motility and its capacity to invade surrounding tissue. Furthermore, when the researchers experimentally equipped the cancer cells with additional miR-200c, the amount of tissue-anchoring molecules on their surface increased and their invasive capacity became lower.
Dr. Allgayer's team also reported that in the highly aggressive cells, the miR-200c genes were turned off by a chemical labeling with methyl groups, and drugs that removed the labels made the production of miR-200c rise again.
When researchers studied the tumor cells of 69 lung cancer patients, they determined miR-200c levels and compared them with the patients' disease progression data. They found that the lower the miR-200c level in the cancer cells, the more frequently metastasis had already begun.
“Our results clearly show a connection between a loss of miR-200c and transition to aggressive, invasive growth, metastasis, and chemoresistance,” concluded Dr. Allgayer. “Therefore, we will now investigate whether miR-200c production in cancer cells can be used for predicting metastasis and, thus, may serve as a prognosis factor for the progression of a lung cancer. It is also possible that the miR-200c level can help to better predict the effectiveness of particular drugs.”