In BMC Cancer this week, researchers in Japan report on hepatitis B core promoter mutations, which are significantly associated with hepatocellular carcinoma in certain hepatitis B-infected patients. The team compared the full genome sequences of the hepatitis B virus from the blood of 37 patients with liver cancer and 38 patients without cancer. They also analyzed part of the core promoter region sequences from another 40 liver cancer patients and a second group of non-cancer patients. Of the second non-cancer group, 16 eventually developed liver cancer, and after the researchers analyzed the DNA of their viruses, it was found that all 16 patients had virus genotype C. "A comparison of the nucleotide sequences of the HBV genome between HCC group 1 and non-HCC group 1 revealed that the prevalence of G1613A and C1653T mutations in the core promoter region was significantly higher in the HCC group," the authors write. "These mutations tended to occur simultaneously in HCC patients. Multivariate analysis with group 2 revealed that the presence of HCC was associated with aging and the double mutation." These mutations, the team adds, may serve as useful biomarkers for tracking the development of liver cancer in patients.
Also in BMC Cancer this week, researchers in the US and China report the effects of plant lignan magnolol on the development of UVB-induced skin cancer in mice. Magnolol is derived from the bark and seed cones of magnolia trees, and has been shown to have chemopreventive effects on chemically induced skin cancer, the authors write. For this study, the team developed a UVB-induced complete carcinogenesis mouse model, and found that the animals treated with magnolol before being subjected to UVB had a 27 percent to 55 percent reduction in tumor multiplicity, compared to the control group. In addition, treatment of skin cancer cell lines with magnolol decreased cell viability and proliferation. "Magnolol pretreatments prevent UVB-induced skin cancer development by enhancing apoptosis and causing cell cycle arrest at G2/M phase, and affecting various signaling pathways," the authors write. "Magnolol could be a potentially safe and potent anticarcinogenic agent for skin cancer."
Finally in BMC Cancer this week, another group of Japanese researchers reports on the clinical implications of the expression of HLA-class I molecules in breast cancer. The team analyzed data from 212 breast cancer patients who received curative surgery from 1993 to 2003. They observed down-regulation of HLA-class I expression in the cancers of 69 patients, and found that HLA-class I down-regulation was significantly associated with nodal involvement, lymphatic and venous invasion, and higher stage. "Patients with preserved HLA class I had significantly better disease-free interval than those with loss of HLA class I," the authors write. "The examination of HLA class I expression is useful for the prediction of tumor progression and recurrent risk of breast cancer via the antitumor immune system."