Tag Archives: mutations

International team completes systematic, genomic study of cervical cancer

The study, which appears online in Nature, addresses a public health concern of global significance: cervical cancer is the second most common cancer in women and is responsible for approximately 10 percent of cancer deaths in women — particularly in developing countries where screening methods are not readily accessible. Almost all cases of the disease are caused by exposure to HPV and it is expected that vaccination efforts targeting HPV will decrease cervical cancer cases over time. In the meantime, however, the disease remains a significant threat to women’s health. …

Ceratin gene mutations make breast cancers treatment-resistant

Treatment given to shrink or eliminate a tumor before surgery is called neoadjuvant therapy. In some women with breast cancer treated with neoadjuvant therapy, no residual invasive cancer can be detected in breast tissue samples and lymph nodes removed during surgery. Emerging data suggest that these women, who are said to have had a pathologic complete response, have a greater chance of long-term survival compared with women who do not have a pathologic complete response. "Mutations in the PIK3CA gene are among the most common genetic aberrations in breast cancer," said Sibylle Loibl, M.D., professor at the German Breast Group in Neu-Isenburg, Germany. …

Scientists fingerprint single cancer cells to map cancer’s family tree

The technique can identify the founding mutations from which a tumour evolved and then uses computer software to draw a map of the cancer’s family tree. Scientists at The Institute of Cancer Research, London, and the Wellcome Trust Sanger Institute used DNA sequencing to identify a panel of mutations present across thousands of cancer cells in three patients with leukaemia…

Mutations in cancer often affect the X chromosome

By studying when and where mutations occur the researchers hope to gain insights into the early mechanisms that send cells along a pathway to cancer. The new international study coordinated by Roland Eils has now for the first time analyzed the exact distribution of somatic mutations in the genomes of tumor cells of various types of cancer. Mutations do not affect all regions of the genome to the same extent. It is known, for example, that the number of somatic mutations depends on the sequence of bases making up a gene and the frequency at which it is transcribed into RNA molecules. …

Potential new drug for some patients with treatment-resistant lung cancer

Mutations in the growth factor gene EGFR are present in about 10 to 15 percent of patients with the most common form of lung cancer, non-small cell lung cancer (NSCLC). Most NSCLCs harboring these EGFR mutations, called activating mutations, respond to the EGFR inhibitor drugs erlotinib and gefitinib. A majority of such cancers, however, develop resistance to these drugs within about nine to 11 months. …

Early puberty may be caused by gene mutation

When a child enters puberty earlier than expected, doctors are often at a loss to explain why. But now, researchers have discovered a genetic mutation that they say causes some cases of early puberty. In the study, the researchers in Brazil screened the genomes of 32 people with early puberty from 15 families. (Some cases of early puberty run in families.) Mutations in a gene called MKRN3 were found in 15 people from five of the families. In all of these cases, the mutated MKRN3 gene was inherited from the father, the researchers said. Early puberty, also called precocious puberty, is puberty that occurs before age 8 in girls, or age 9 in boys. Some cases are caused by brain tumors or thyroid problems, but in many cases, a cause is not identified. The average age of puberty onset for those with mutations in the MKRN3 gene was about age 6 for girls, and age 8 for boys. It's not clear exactly how MKRN3 plays a role in puberty, but it may be involved in releasing the “brake” that normally prevents puberty from starting, Dr. Ieuan Hughes, of Cambridge University in the United Kingdom, wrote in an editorial accompanying the study. Puberty begins when the brain starts producing higher levels of a hormone called gonadotropin-releasing hormone. Mutations in the MKRN3 gene may trigger an increase in levels of this hormone at an earlier age, the researchers said. To further investigate the role of MKRN3 in puberty, the researchers studied the brains of mice. They found that levels of MKRN3 gene expression were highest when the mice were young, and reached a low point at the start of puberty, which provides more evidence to tie this gene to puberty. The study is published online June 5 in the New England Journal of Medicine. Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.source : http://www.foxnews.com/health/2013/06/06/early-puberty-may-be-caused-by-gene-mutation/