A new study has found that cyclin D1, a protein that helps push a replicating cell through the cell cycle also mediates the processing and generation of mature microRNA (miRNA).

The research suggests that a protein strongly implicated in human cancer also governs the non-protein-coding genome.

The non-coding genome, previously referred to as junk DNA, makes up most of the human genome, and unlike the coding genome, varies greatly between species.

"In addition to its role in regulating the cell cycle, cyclin D1 induces Dicer and thereby promotes the maturation of miRNA," lead researcher Richard Pestell, M.D., Ph.D., Director of the Kimmel Cancer Center at Thomas Jefferson University and Chair of the Department of Cancer Biology, said.

Dicer is a protein that converts inactive hairpin-structured microRNA precursors into their active single stranded form.

"The work supports the idea that cancer-causing proteins like cyclin D1 may drive cancer progression in part via miRNA biogenesis," he said.

Using antisense RNA, Dr. Pestell's group was the first to show that cyclin D1 drives mammary tumor growth in vivo.

In prior work, they showed that cyclin D1 regulates the non coding genome, and that the non-coding genome, in turn, regulates expression of cyclin D1.

Furthermore, the group showed that many cancer patients encode a form of cyclin D1 that evades negative feedback from the non coding genome.

These attenuating feedback loops between the non-coding and coding genome may be a common theme in cancer and other biological processes.

In the current study, the group sought to investigate the mechanism by which cyclin D1 regulates the biogenesis of non coding miRNA.

Dr. Pestell and colleagues developed transgenic mice that could induce cyclin D1 expression in the breast and examined cells with cyclin D1 gene deleted.

The researchers noticed that cells lacking cyclin D1 produced less of the miRNA-processing protein, Dicer, and therefore had reduced levels of mature miRNA.

The study is published in the journal Nature Communications.

A new study has found that women who are members of families with BRCA2 mutations but who test negative for the family-specific BRCA2 mutations are still at greater risk for developing breast cancer compared with women in the general population.

Women with certain mutations in their BRCA1 or BRCA2 genes are at increased risk for breast cancer. However, the study suggested that it may not always be true.

"We found that women who test negative for family-specific BRCA2 mutations have more than four times the risk for developing breast cancer than the general population," Gareth R. Evans from University of Manchester in the United Kingdom, said. "We also found that any increased risk for breast cancer is largely limited to BRCA2 families with strong family history and other genetic factors.

Evans said that it is likely that these women inherit genetic factors other than BRCA-related genes that increase their breast cancer risk. About 77 single nucleotide polymorphisms are linked to breast cancer risk.

He said that identification of additional SNPs is necessary to understand why some of the BRCA-negative women from BRCA families are at higher risk.

The authors noted that specialists should use caution when stating that a woman's breast cancer risk is the same as that of the general population following a negative test, because it may not be true for some women who come from BRCA2 families with a strong family history.

The study is published in journal Cancer Epidemiology, Biomarkers and Prevention.

For patients with diabetes, it is better to eat a single large meal than several smaller meals throughout the day, a new study has found.

Researchers at Linkoping University in Sweden studied the effect on blood glucose, blood lipids and different hormones after meals were compared using three different macronutrient compositions in patients with type 2 diabetes.

The three diets were a low-fat diet, a low-carbohydrate diet and a Mediterranean diet. The scientists included 21 patients that tested all three diets in a randomised order. During each test day blood samples were collected at six time points.

The low-fat diet had a nutrient composition that has traditionally been recommended in the Nordic countries, with about 55 per cent of the total energy from carbohydrates.

The low-carbohydrate diet had a relatively low content of carbohydrate; approximately 20 per cent of the energy was from carbohydrates and about 50 per cent of the total energy came from fat.

The Mediterranean diet was composed of only a cup of black coffee for breakfast, and with all the caloric content corresponding to breakfast and lunch during the other two test days accumulated to one large lunch.

Furthermore, the total caloric content included energy from 150 ml (women) to 200 ml (men) of French red wine to ingest with the lunch.

The food in the Mediterranean diet had an energy content from carbohydrates that was intermediate between the low-fat and the low-carbohydrate meals, and sources of fat were mainly olives and fatty fish.

"We found that the low-carbohydrate diet increased blood glucose levels much less than the low-fat diet but that levels of triglycerides tended to be high compared to the low-fat diet," said Doctor Hans Guldbrand, who together with Professor Fredrik Nystrom was the principal investigator of the study.

"It is very interesting that the Mediterranean diet, without breakfast and with a massive lunch with wine, did not induce higher blood glucose levels than the low-fat diet lunch, despite such a large single meal," said Nystrom.

"This suggests that it is favourable to have a large meal instead of several smaller meals when you have diabetes, and it is surprising how often one today refers to the usefulness of the so-called Mediterranean diet but forgets that it also traditionally meant the absence of a breakfast," Nystrom said.

"Our results give reason to reconsider both nutritional composition and meal arrangements for patients with diabetes," Nystrom said.

Women suffering from diabetes and wishing to start a family should monitor their blood glucose levels and take a daily high dose of folic acid before pregnancy to avoid risk to their baby's health, a new study said Wednesday.

The risk of stillbirth - when the foetus dies in the uterus or death during the first year of birth - was over four times greater in women with diabetes than in those without the disease.

The team from Newcastle University studied the outcome of over 400,000 pregnancies delivered in north of England between 1996 and 2008.

"We found that 2.7 percent of births in women with diabetes resulted in stillbirth, six times than the rate for women without diabetes, while 0.7 percent died during the first year of life, nearly double the rate in women without diabetes," said Ruth Bell, one of the researchers.

The research also said that nearly 40 percent of deaths might have been avoided if all of the women were able to achieve good control of their blood glucose before pregnancy.

"Stillbirths and infant deaths are thankfully not common, but they could be even less common if all women with diabetes can be helped to achieve the best possible control of their blood glucose levels before becoming pregnant," added Bell.

COPD patients can improve their lung function by practicing yoga, a new research led by Indian origin scientist has revealed.

The study by researchers at the All India Institute of Medical Sciences, Department of Pulmonary Medicine and Sleep Disorders found that lung function, shortness of breath, and inflammation all showed significant improvement after patients completed 12 weeks of training.

"COPD is a systemic inflammatory disease that causes difficulty breathing. We investigated to see whether simple, structured yoga training affects the level of inflammation, shortness of breath, and quality of life in patients with stable COPD," study presenter Randeep Guleria said.

The study included 29 stable patients with COPD who received yoga training in a format that included the use of physical postures (asanas), breathing techniques (pranayama), cleansing techniques, (kriyas), meditation, and a relaxation technique (shavasan) for 1 hour, twice a week, for 4 weeks.

Following the 4-week period, patients were trained for 1 hour every 2 weeks, with the remaining sessions completed at home. Patients were evaluated on assessment of lung function, breathing, quality of life, and inflammation status.
A repeat assessment was done at the end of the 12-week training session. All parameters showed significant improvement at the end of the 12-week period.

Guleria said that yoga can be a simple, cost-effective method that can help improve quality of life in patients with COPD .

The study was presented at CHEST 2013.