Antioxidant enzyme expression and reactive oxygen species damage in prostatic intraepithelial neoplasia and cancer

Abstract

SOD1, SOD2, and catalase had lower expression in PIN and prostate carcinoma than in benign epithelium. The number of immunoreactive cells in PIN was similar to cancer, indicating that these are closely related. Enzyme activities were variable, with no difference between benign epithelial cells and cancer, although this lack of change in enzyme activity could have been due to the presence of contaminating benign cells within the cancer specimens. The results of reactive oxygen species damage were found only in the epithelium and not in the stroma. Expression of the DNA adduct 8-hydroxydeoxyguanosine was present in fewer than 3% of cells, with no apparent differences among benign epithelium, PIN, and cancer. These findings suggest that oxidative stress is an early event in carcinogenesis.

Sodium Selenite Radiosensitizes Hormone-Refractory Prostate Cancer Xenograft Tumors but Not Intestinal Crypt Cells In Vivo

“…As we previously reported in studies comparing normal prostate and prostate cancer primary cell lines (5), there are important differences in factors, such as inherent levels of manganese superoxide dismutase and the effect of SSE on Bcl-2 family members, that may explain, in part, the resistance of normal gastrointestinal epithelium to SSE and the absence of a radiosensitizing effect in this normal tissue. In addition, other antioxidant enzymes, such as catalase, are deficient in some prostate cancer cells (5,19). Such a relative deficiency could enhance SSE-mediated reactive oxygen species generation and GSH depletion.…”

Advanced prostate cancer: reinforcing the strings between inflammation and the metastatic behavior

“…70 Evidently, there is a connection between oxidative stress and androgen deprivation in prostate cancer, which is also supported by previous observations of increased oxidative damage associated to the development of malignancies. 71 Of interest, when comparing CRPC gene expression profile with hormonal-sensitive tumors, the antioxidant defense endogenous system is clearly repressed, in particular SOD2 (manganese superoxide dismutase). 72 SOD2 regulates ROS production by converting superoxide to a less reactive species.…”

Trace elements in human cancerous and healthy tissues: A comparative study by EDXRF, TXRF, synchrotron radiation and PIXE

“…Bostwick et al [40] to be the most important in distinguishing between malignant and normal lung tissues are Fe, Mn and Cu (see Table 2). …”