Tag Archives: cell

Study revises theory of how PTEN, a critical tumor suppressor, shuts off growth signals

Today, scientists at Cold Spring Harbor Laboratory (CSHL) publish new evidence explaining precisely how the protein encoded by PTEN (called PTEN) works — specifically, how it is recruited to particular locations in our cells where pro-growth signals need to be shut off. The new evidence, assembled by a team led by CSHL Associate Professor Lloyd Trotman, contradicts a long-held assumption about PTEN function, and could help scientists design more effective drugs to counteract cancer’s hallmark trait, uncontrolled cellular growth…

Swine flu outbreak in India raises concern: New strain of H1N1 may carry dangerous mutations

The findings, which appear in the March 11 issue of Cell Host & Microbe, contradict previous reports from Indian health officials that the strain has not changed from the version of H1N1 that emerged in 2009 and has been circulating around the world ever since. With very little scientific data available about the new strain, the MIT researchers stress the need for better surveillance to track the outbreak and to help scientists to determine how to respond to this influenza variant. …

Growth signal can influence cancer cells’ vulnerability to drugs, study suggests

“There are several reasons why some cancer stem cells, the cells at the root of tumors and metastases, can withstand therapy meant to eradicate them. Our results point to the importance of the environment immediately surrounding the skin cancer stem cells, specifically, their exposure to the signal TGF-β,” says senior researcher Elaine Fuchs. “Ultimately, we hope this new insight could lead to better means for preventing the recurrence of these life-threatening cancers, which can occur in the skin, head, neck, esophagus, and lung, and often evade treatment.” Her team, which included first author Naoki Oshimori, a postdoctoral research associate in the lab and lab technician Daniel Oristian, focused on squamous cell carcinomas in the skin of mice. Like many normal tissue stem cells, the stem cells that produce squamous cell tumors can be classified into two types: those that divide and proliferate rapidly, and those that do so more slowly. …

New target for prostate cancer treatment discovered

Prostate cancer is the second most common cancer in American men, after skin cancer, according to the American Cancer Society (ACS). The ACS projects more than 27,000 deaths from prostate cancer in 2015 and is the second leading cause of cancer death in American men, behind lung cancer. One man in seven will be diagnosed with prostate cancer during his lifetime…

Human neural stem cells restore cognitive functions impaired by chemotherapy

In preclinical studies using rodents, they found that stem cells transplanted one week after the completion of a series of chemotherapy sessions restored a range of cognitive functions, as measured one month later using a comprehensive platform of behavioral testing. In contrast, rats not treated with stem cells showed significant learning and memory impairment. The frequent use of chemotherapy to combat multiple cancers can produce severe cognitive dysfunction, often referred to as “chemobrain,” which can persist and manifest in many ways long after the end of treatments in as many as 75 percent of survivors — a problem of particular concern with pediatric patients. “Our findings provide the first solid evidence that transplantation of human neural stem cells can be used to reverse chemotherapeutic-induced damage of healthy tissue in the brain,” said Charles Limoli, a UCI professor of radiation oncology…

Cancer researchers may inspire new area of research in cellular biology

A research collaboration between Griffith and the Malaghan Institute in Wellington, New Zealand has made the discovery that mitochondria are capable of passing through the healthy membrane of a host cell into defective tumour cells, possibly kicking off the rapid proliferation of tumour cells which is the hallmark of cancer. Until now each cell was believed to be a unique entity, with mitochondria and mitochondrial DNA (mtDNA) bound within the cell membrane. …

Role of gene mutations involved in more than 75 percent of glioblastomas, melanomas

The research is published this month in the online journal PLOS ONE and is authored by Brad Chaires, Ph.D., John Trent, Ph.D., Robert Gray, William Dean, Ph.D., Robert Buscaglia, Shelia Thomas and Donald Miller, M.D., Ph.D. Telomerase is an enzyme largely responsible for the promotion of cell division. Within DNA, telomerase activation is a critical step for human carcinogenesis through the maintenance of telomeres. …

Proteins drive cancer cells to change states

Biologists have previously found that this kind of transformation, which often occurs in cancer cells as well as during embryonic development, is controlled by transcription factors — proteins that turn genes on and off. However, the new MIT research reveals that RNA-binding proteins also play an important role. Human cells have about 500 different RNA-binding proteins, which influence gene expression by regulating messenger RNA, the molecule that carries DNA’s instructions to the rest of the cell. “Recent discoveries show that there’s a lot of RNA-processing that happens in human cells and mammalian cells in general,” says Yarden Katz, a recent MIT PhD recipient and one of the lead authors of the new paper…