Working with cancerous prostate tissues of men over 55 years of age, scientists at the Pacific Northwest Research Institute (PNRI) in Seattle have identified a DNA structure that potentially signals a high risk for prostate cancer.
The researchers believe that this structure can be used as a biomarker for assessing prostate cancer risk and as a target for early intervention.
The DNA phenotype was found to be indistinguishable from the DNA structure identified in prostate tumors, and now appears to be structurally stable as it has been confirmed to be present in normal tissues surrounding tumors.
The lead researcher, Donald C. Malins, points out that this abnormal DNA structure is probably intimately associated with tumor development.
Malins states that the potential exists to inhibit or eliminate this cancer DNA phenotype with drug intervention, thereby reducing the risk for prostate cancer.
The study is reported in the early online edition of the Proceedings of the National Academy of Sciences during the week of Dec 12th.
Previous studies by the PNRI research team found that mice injected with a known carcinogen produced a comparable cancer DNA phenotype about 8 weeks prior to tumor development.
Encouragingly, the researchers were able to virtually eliminate this phenotype through intervention with a drug (cyclophosphamide) that also substantially delayed tumor formation.
According to Malins, the present findings, together with the previous findings with mice, "support the concept that cancer risk can be predicted by identifying the cancer DNA phenotype in normal tissues, long before any tumors appear."
He also states that "exposure to oxidizing chemical species, such as free radicals, that form in the body from environmental and/or dietary exposures to toxic chemicals likely contribute to the development of the cancer DNA phenotype."
The next step is to demonstrate that the phenotype can actually be used by physicians to predict the risk of prostate cancer.
Malins stresses the importance of testing drugs, such as those with antioxidant properties, to eliminate or delay the formation of the phenotype before tumors start to form.