When working correctly, PGP pumps chemotherapeutic drugs out of tumors, allowing the tumor cells to survive. This response is known as drug resistance. Working with collaborators in five countries, McLeod and his colleagues did DNA tests on blood samples from 1,280 people from 10 ethnic populations. They found that some populations were significantly more likely than others to contain the mutation. Because lack of the mutation is associated with higher expression of PGP and thus higher drug resistance, these findings mean that physicians may soon have the necessary tools for individualizing therapy, especially for people of African heritage.
Many factors affect survival rates among cancer patients.
Knowing this, we should be able to help decrease the variability in the way people are treated. Previous studies have shown that there are ethnic and racial differences in the ability to make several proteins important for successful drug therapy. Frequency of the C3435T mutation in exon 26 is significantly influenced by ethnicity. Presented at American Association for Cancer Research Annual Meeting March 24, 2001. Funding from the Wellcome Trust supported this research.