@article{oai:nagasaki-u.repo.nii.ac.jp:00016399,
 author = {Osaka, Akemi and Hasegawa, Hiroo and Yamada, Yasuaki and Yanagihara, Katsunori and Hayashi, Tomayoshi and Mine, Mariko and Aoyama, Muneo and Sawada, Takashi and Kamihira, Shimeru},
 issue = {3},
 journal = {Journal of cancer research and clinical oncology},
 month = {Mar},
 note = {PURPOSE: This study aimed to evaluate serum cytochrome c (cyto-c) levels as a novel role of tumor marker in patients with operable malignant tumors. METHODS: Serum cyto-c levels and lactate dehydrogenase (LD) activity were measured in a total of 257 cases (232 malignant and 25 benign). To identify the relationship between serum cyto-c and current tumor markers, six variables, such as gender, age, invasion, lymph node metastasis, distant metastasis, and LD, were analyzed by uni- and multivariate regression analysis methods. The test performance of serum cyto-c for the prediction of malignant behavior was evaluated by receiver operating characteristic (ROC) curves. RESULTS: The serum cyto-c level was significantly higher in patients with malignant tumors than patients with benign tumors (20.6 vs. 15.5 ng/mL; P = 0.017, Mann-Whitney U test). No difference in the levels among subtypes of cancer was found, indicating that the change in serum cyto-c levels reflect cancer individually and not specific subtypes of cancer. The survival in patients with serum cyto-c levels over 40 ng/mL was poor (Kaplan-Meier test, P < 0.0001, Hazard ratio 16.76, 95% confidential interval 4.45-63.04). Multiple linear regression analyses disclosed the close association of serum cyto-c levels with invasion (P = 0.0004), metastasis (P = 0.0262) except for regional lymph node metastasis, and activity of serum LD (P < 0.0001), all of which are well known to represent malignant behavior. Conversely, the measurement of serum cyto-c was verified to have excellent diagnostic accuracy of 0.802 and 0.781 for the detection of invasion and metastasis (the area under curves of the constructed ROCs). CONCLUSION: Serum cyto-c is a potent tumor marker as a predictor for malignant potential in cancers., Journal of cancer research and clinical oncology, 135(3), pp.371-377; 2009},
 pages = {371--377},
 title = {A novel role of serum cytochrome c as a tumor marker in patients with operable cancer.},
 volume = {135},
 year = {2009}
}