Patients with xeroderma pigmentosum, a disease characterized by severe sensitivity to UV radiation and a defect in nucleotide excision repair, have a high incidence of cutaneous malignant melanoma, which suggests that DNA repair capacity may also play a role in sunlight-induced melanoma within the general population. Qingyi Wei, M.D., Ph.D., and colleagues at the University of Texas M. D. Anderson Cancer Center, Houston, conducted a study of DNA repair capacity and melanoma among 312 patients with cutaneous malignant melanoma and 324 cancer-free control subjects.
They found that case patients had a 19% lower mean DNA repair capacity than control subjects, and that a DNA repair capacity at or below the median value of that in control subjects was associated with increased risk for melanoma. Patients with tumors on sun-exposed skin had a lower DNA repair capacity than patients with tumors on unexposed skin.
Contact: Laura Sussman, M. D. Anderson Cancer Center, 713-792-0655, lsussman@mdanderson.org
Natural compound shows promise as lung cancer chemoprevention agent
A natural compound called deguelin may have potential as both a chemopreventive agent and a therapeutic agent against lung cancer, according to a study in the February 19 issue of the Journal of the National Cancer Institute .
Deguelin, present in several plant species, including Mundulea sericea , is in a class of compounds called rotenoids, which have been found to exhibit chemopreventive activity. Kyung-Hee Chun and Ho-Young Lee, Ph.D., of the M. D. Anderson Cancer Center, and their colleagues evaluated the chemopreventive effects of deguelin in normal, premalignant, and malignant human bronchial epithelial cells.
Deguelin inhibited the growth of and induced apoptosis of premalignant and malignant human bronchial epithelial cells by affecting the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. However, deguelin had minimal effects on the normal bronchial cells. The authors conclude that the ability of deguelin to inhibit PI3K/Akt-mediated signaling pathways may contribute to the potency and specificity of this drug and that, because both premalignant and malignant bronchial cells are more sensitive to deguelin than normal bronchial cells, deguelin may have potential as both a chemopreventive agent and a therapeutic agent against lung cancer.
Also in the February 19 JNCI:
Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage.
JNCI Journal of the National Cancer Institute