Pancreatic cancer is the fifth leading cause of cancer deaths in the developed world, and is extremely difficult to treat. Only 3% of affected patients are still alive five years after diagnosis, a survival rate that has remained static for the past three decades.

Currently, the only viable treatment is surgery. Radiotherapy and chemotherapy have little impact on the disease.

The research team investigated the potential of the protein vasostatin to suppress the development of new blood vessels and pancreatic tumour cells both in test tubes and in mice with pancreatic cancer.

'Solid' tumours, such as pancreatic cancer, are heavily dependent on a rich blood supply to enable them to grow rapidly and spread throughout the body. This process is known as angiogenesis.

The protein gene was incorporated into a virus (adenovirus), so that it would be able to penetrate the cells, acting as a vector.

The test tube experiments showed that 72 hours after infection with the genetically modified virus, vasostatin was clearly active in the tissue. Tumour growth in the mice was also curbed, and when compared with mice which had not been infected with the virus, the difference between the two groups was highly significant.

The researchers then looked more closely at the pancreatic cells and the cell linings of the blood vessels (vascular endothelial cells).

They found that although vasostatin seemed to have little impact on the pancreatic cells, it blocked the formation of new blood vessels, effectively cutting off the supply of nutrients to the malignant cells. This effect was seen in both the test tube and animal experiments.

This type of gene therapy "may be a potent strategy to treat many malignant tumours, including pancreatic cancer, and represents a promising therapeutic option for malignancy with a poor prognosis," conclude the authors.

gut.bmjjournals/

The paper describes the history of the Jewish people as providing perhaps the best-documented example of how genetic similarity intersects culture, history, and even politics.

Jewish groups are genetically similar to each other even though they have been separated for two millennia. Jews from Iraq and Libya share more genes with Jews from Germany and Russia than either group shares with the non-Jewish populations among whom they have lived over the intervening centuries.

Recent DNA studies of the ancient Hindu caste system has confirmed that upper castes are more genetically related to Europeans than are lower castes who are genetically more related to other south Asians. Although outlawed in 1960, the caste system continues to be the main feature of Indian society, with powerful political repercussions.

The paper described the group-identification processes as innate--part of the evolved machinery of the human mind. Even very young children make in-group/out-group distinctions about race and ethnicity in the absence of social learning.

charlesdarwinresearch/