Hasan Hathama Razooki, Mathkor Thikra Hasan, Al-Habal Mohammed Hasan
Department of Chemistry, College of Science, University of Baghdad, Baghdad, Iraq.
Asian Pac J Cancer Prev. 2012;13(6):2571-6. doi: 10.7314/apjcp.2012.13.6.2571.
Breast cancer is the first of the most common ten cancers in Iraq. Its etiology is mulifactorial, oxidative stress and lipid peroxidation being suggested to play important roles in carcinogenesis. The purpose of this study was to investigate the oxidant-antioxidant status in breast cancer patients, by measuring SOD isoenzyme activities (total SOD, CuZn-SOD, Mn-SOD and EC-SOD) in plasma and breast tumors, and by estimating thiobarbituric reactive substance (TBRS) in tissue homogenates. General increase in total SOD activity was observed in plasma and tissue samples of breast tumors, greater in the malignant when compared to benign group (p<0.05). Mn- SOD showed a significant decrease in tissue malignant samples (p<0.05), and insignificant decrease in plasma malignant samples compared with control and benign samples. Plasma EC-SOD activity in both patient benign and malignant breast tumors demonstrated 3.5% and 22.8% increase, respectively. However, there was a decrease in tissue EC-SOD activity in malignant breast tumors when compared with benign. A similar tendency was noted for TBRS.We suggested that elevated total SOD might reflect a response to oxidative stress, and then may predict a state of excess reactive oxygen species in the carcinogenesis process. If there is proteolytic removal of the heparin binding domain, EC-SOD will lose its affinity for the extracellular matrix and diffuse out of the tissue. This will result in a decreased EC-SOD activity, thus leading to an increase in the steady-state concentration of O2- in this domain, and increase in EC-SOD activity in extracellular fluid. This might explain the result recorded here concerning the decrease in tissue EC-SOD activity and increase in plasma of breast cancer patients.
乳腺癌是伊拉克最常见的十种癌症中的首位。其病因是多因素的，氧化应激和脂质过氧化被认为在致癌过程中起重要作用。本研究的目的是通过测量血浆和乳腺肿瘤中SOD同工酶活性（总SOD、铜锌SOD、锰SOD和细胞外SOD）以及估计组织匀浆中的硫代巴比妥酸反应物质（TBRS），来研究乳腺癌患者的氧化-抗氧化状态。在乳腺肿瘤的血浆和组织样本中观察到总SOD活性普遍增加，恶性组比良性组更高（p<0.05）。与对照组和良性样本相比，锰SOD在组织恶性样本中显著降低（p<0.05），在血浆恶性样本中降低不显著。乳腺肿瘤患者良性和恶性组的血浆细胞外SOD活性分别增加了3.5%和22.8%。然而，与良性乳腺肿瘤相比，恶性乳腺肿瘤组织中的细胞外SOD活性降低。TBRS也有类似趋势。我们认为总SOD升高可能反映了对氧化应激的反应，进而可能预示着致癌过程中活性氧物种过量的状态。如果肝素结合域被蛋白水解去除，细胞外SOD将失去对细胞外基质的亲和力并扩散出组织。这将导致细胞外SOD活性降低，从而导致该区域超氧阴离子稳态浓度增加，细胞外液中细胞外SOD活性增加。这可能解释了此处记录的乳腺癌患者组织细胞外SOD活性降低和血浆中增加的结果。
