Influence of oxidative injury and monitoring of blood plasma by DSC on breast cancer patients Istva ´n Zapf 1 • Medhi Moezzi 2 • Tama ´s Fekecs 3 • Kla ´ra Nedvig 4 • De ´nes L} orinczy 5 • Andrea Ferencz 6 Received: 28 November 2014 / Accepted: 11 March 2015 Ó Akade ´miai Kiado ´, Budapest, Hungary 2015 Abstract Damage caused by oxidative stress is involved in many types of diseases, including breast cancer. Our aim was to detect the oxidative stress parameters and blood plasma changes with differential scanning calorimetry (DSC) in breast cancer patients. The study included 40 adult breast cancer women who were grouped according to tumor diameter, regional lymph node metastases, proliferative ac- tivity, receptor status and postoperative chemotherapy. To monitor oxidative stress, malondialdehyde, oxygen free radicals (OFRs), activity of myeloperoxidase (MPO), su- peroxide dismutase (SOD) and catalase (CAT) were mea- sured. Denaturation of plasma components was detected in Setaram Micro DSC-II calorimeter. The total production of OFRs, the MPO activity and lipidperoxidation were sig- nificantly increased in each breast cancer patients consid- ering the tumor size, the metastatic lymph nodes, the proliferation activity and receptor status compared with healthy controls (p \ 0.05). These pro-oxidants were slightly elevated without chemotherapy, but their values were increased significantly in chemotherapy-receiving group. The activity of SOD and CAT was significantly de- creased in all groups, and in regard to the chemotherapy, they were changed significantly parallel to the severity of disease. Regarding to both the increased tumor diameter and the increased number of affected lymph nodes, DSC mea- surements showed a strong relationship between the max- imum excess heat capacity (C pmax ) of the blood plasma and the severity of disease. The study demonstrated that oxida- tive stress is implicated in breast carcinoma and che- motherapy aggravates these changes which confirmed the plasma DSC measurements also. Keywords Breast cancer Á Oxidative stress Á DSC Á Diagnosis Á Monitoring Introduction Damages caused by oxidative stress are involved in many types of systemic age-dependent diseases, including atherosclerosis, diabetes, hypertension, inflammatory and oncological conditions [1, 2]. Among cancers, breast can- cer is the most common tumor in women and has the highest mortality rate in the world. The etiology of the breast cancer is multifactorial, and besides genetic predis- position, the most known environmental risk factors (age, obesity, drugs, hormones, etc.) have been linked to the oxidative damage to the breast cells also [3, 4]. According to the newest theory of carcinogenesis, it is a complex multi-sequence process leading from a healthy cell through a precancerous state finally to the cancer. Oxygen free radicals (OFRs) have a key role during the & Andrea Ferencz andrea.ferencz@gmail.com 1 Surgery Clinic, Medical School, University of Pe ´cs, Ra ´ko ´czi Str. 2, Pecs 7624, Hungary 2 Department of Dermatology, Venereology and Oncodermatology, Medical School, University of Pe ´cs, Aka ´c Str. 1, Pecs 7632, Hungary 3 Government Office of Baranya County, Jo ´zsef A. Str. 10, Pecs 7623, Hungary 4 General and Vascular Surgical Department, Zala County Hospital, Zrı ´nyi Str. 1, Zalaegerszeg, 8900, Hungary 5 Department of Biophysics, Medical School, University of Pe ´cs, Szigeti Str. 12, Pecs 7624, Hungary 6 Department of Surgical Research and Techniques, Medical Faculty, Semmelweis University, Nagyva ´rad Str. 4, Budapest 1089, Hungary 123 J Therm Anal Calorim DOI 10.1007/s10973-015-4642-9