cancer
Oral administration of a drug that inhibits a process known as DNA methylation results in a reduction in the size of malignant tumors in mice, according to a team of researchers led by scientists from the Keck School of Medicine of the University of Southern California. The drug, called zebularine, accomplishes its tumor-whittling by turning on tumor suppressor genes that have been turned off by methylation.
New work by researchers in the Kimmel Cancer Center at Johns Hopkins may allow them to halt the smoking-induced cellular events that lead to 99 percent of all small cell lung cancers (SCLC). The research is reported in the March 5, 2003, issue of Nature. The researchers found that a primitive cellular pathway, called Sonic Hedgehog (named for the cartoon character and spiky hairs it develops on fruit flies) stays turned on long after it should be turned off in some lung cancers.
Scientists have discovered that the genetic mutation that causes the childhood cancer retinoblastoma routinely triggers fetal death and miscarriage in laboratory animals by disrupting the normal functions of the placenta, a finding that may force researchers to reevaluate the powerful Rb gene and the role it plays in causing cancer.
Although the benefits of green tea are widely touted, a study conducted by Mayo Clinic Cancer Center and North Central Cancer Treatment Group shows green tea is not an effective treatment for advanced prostate cancer. "Previous laboratory studies suggested that green tea might be an effective anticancer treatment," says Aminah Jatoi, M.D., a Mayo Clinic medical oncologist and lead researcher on the study. "However, in our study of 42 patients with advanced androgen-independent prostate cancer, only one patient showed a short-term drop in his prostate-specific antigen (PSA) levels.
Fruits and veggies grown organically show significantly higher levels of cancer-fighting antioxidants than conventionally grown foods, according to a new study of corn, strawberries and marionberries. The research suggests that pesticides and herbicides actually thwart the production of phenolics ? chemicals that act as a plant's natural defense and also happen to be good for our health. Fertilizers, however, seem to boost the levels of anti-cancer compounds.
A relatively brief screening test can give caregivers a good indication of which cancer survivors are emotionally distressed and may benefit from further psychological evaluation, according to new research by a team of Dana-Farber Cancer Institute investigators. In a study in the March 1 issue of the Journal of Clinical Oncology, the researchers found that childhood cancer survivors whose screening scores indicated they were dissatisfied with their physical appearance, were in poor physical health, or had been treated with head radiation had an increased risk of experiencing psychological distress.
Researchers have identified a gene that promotes metastases, the spread of cancer cells through the body. This new understanding of how cancer metastasizes, linking a gene product and migration of cancer cells, may lead to therapies to stop this spread. The results of the study are published in the May 2003 issue of the journal Molecular Biology of the Cell. Richard G. Pestell, M.D., Ph.D. and his research team have been studying the cyclin D1 gene and the protein it produces for the past decade. Now they have found that by "knocking out" this gene, the migration of cells can be halted. The migration of cancer cells through the body is a major reason why cancer is deadly.
Of all the neoplastic cells in human breast cancers, only a small minority - perhaps as few as one in 100 - appear to be capable of forming new malignant tumors, according to just-published research by scientists in the University of Michigan Comprehensive Cancer Center. The discovery could help researchers zero in on the most dangerous cancer cells to develop new, more effective treatments.
Adding two experimental drugs to the standard four-drug chemotherapy regimen has significantly improved survival in patients with non-metastatic Ewing?s sarcoma, a highly malignant bone cancer of children and young adults. The large multi-institutional trial showed that the overall survival rate increased from 61 percent to 72 percent for Ewing?s sarcoma patients with localized disease who underwent the experimental six-drug chemotherapy.
Researchers have developed a way to exploit RNA interference for the first time to silence genes in a wide variety of mammalian cells, including embryonic cells. The study will appear in the Feb. 17 edition of Nature Genetics. This new approach allows genes to be switched off by inserting short pieces of ribonucleic acid (RNA) into developing cells. It is currently being used to help researchers uncover the function of the more than 30,000 genes found in humans, as well as in animal models of important diseases.
Researchers have found that a recently discovered gene plays an essential role in mediating apoptosis, or cell death, in colorectal cancer cells. The gene, PUMA, or p53 up-regulated modulator of apoptosis, is controlled by p53 ? a tumor-suppressing gene that prevents normal cells from turning into life-threatening tumor cells. Previous research has determined that damage to p53 is fundamental to the development of a vast majority of cancers, and inactivation of the growth-controlling function of p53 is critical to the growth and spread of most cancers.
In a demonstration of vaccine therapy's potential for treating lung cancer, scientists report that a prototype vaccine boosted the natural immune response to tumors in a small group of patients with advanced non-small cell lung cancer (NSCLC). Moreover, the vaccine was found to be non-toxic and well-tolerated. Published in the Feb. 15 issue of the Journal of Clinical Oncology, findings from the Phase I clinical trial will provide an impetus for further efforts to develop a vaccine against NSCLC, a difficult-to-treat condition that accounts for roughly 80 percent of all lung cancer cases.
New research suggests that combining the chemotherapy drug paclitaxel with very low doses of the HIV-fighting drug AZT may shrink or even eradicate certain types of cancer tumors. Using both drugs in mice helped inhibit the enzyme telomerase, a component critical to the livelihood of some cancer cells. Telomerase helps to build and maintain telomeres ? protective strands of DNA at each end of a chromosome.
Men diagnosed with localized prostate cancer have typically been faced with "good" news and "bad" news. The "good" news - if there is such a thing when cancer is involved - is that most men are effectively cured of their cancer once the prostate is surgically removed. The "bad" news is that the two most notable side effects of prostate surgery - impotence and incontinence - can be very devastating. Fortunately, significant advances have been made on both fronts, and a Wisconsin urologist has helped develop new techniques to minimize both incontinence and impotence.
Researchers have developed a novel approach to genetically instruct human immune cells to recognize and kill cancer cells in a mouse model. The investigators plan to ultimately apply this strategy in a clinical trial setting for patients with certain forms of leukemias and lymphomas. Scientists at Memorial Sloan-Kettering Cancer Center (MSKCC) genetically engineered an antigen receptor, introduced it into cultured human T cells, and infused the T cells in mice that bear widespread tumor cells. The modified T cells, now able to recognize the targeted antigen present on the tumor cells, eradicated the cancer.
