OBJECTIVE: Cell-free circulating mitochondrial DNA (mtDNA) has been proposed as universal diagnostic and prognostic biomarker in cancer patients. PATIENTS AND METHODS: Cell-free DNA was isolated from 1 ml serum from patients with bladder cancer (BCA, n = 84), renal cell carcinoma (RCC, n = 33), and prostate cancer (CaP, n = 23), and compared with healthy individuals (n = 79). Quantitative real-time PCR was used to analyze the levels of a 79 bp (mtDNA-79), and 220 bp (mtDNA-220) fragment of the mitochondrial specific 16S-RNA. The mitochondrial DNA integrity (mtDNA-integrity) was defined as ratio of mtDNA-220 to mtDNA-79 fragments. RESULTS: In healthy controls, mtDNA-79 levels were increased in male volunteers; mtDNA-230 levels and mtDNA-integrity were correlated with age. Neither mtDNA levels nor mtDNA-integrity were correlated with age or gender in cancer patients. Circulating mtDNA-79 (median 8.75 × 10(6) vs. 0.43 × 10(6) copies/ml) and mtDNA-230 (8.11 × 10(6) vs. 0.27 × 10(6) copies/ml) levels were significantly increased in cancer patients and allowed sensitive (84%) and specific (97%) discrimination from healthy controls. mtDNA levels were unequally distributed among the different cancer entities (mtDNA-79: BCA 9.54 × 10(6) vs. RCC 6.69 × 10(6) vs. CaP 4.48 × 10(6) copies/ml; mtDNA-230: BCA 9.78 × 10(6) vs. RCC 6.74 × 10(6) vs. CaP 1.94 × 10(6) copies/ml). The mtDNA-integrity was increased in RCC and BCA patients compared to control subjects and CaP patients. Serum mtDNA-integrity was correlated with pathological stage in RCC and with tumor grade in BCA patients. CONCLUSION: Circulating mtDNA levels are associated with gender and age in healthy individuals, but not in cancer patients. Quantification of circulating mtDNA may help identify patients with urologic malignancies.
OBJECTIVE: Cell-free circulating mitochondrial DNA (mtDNA) has been proposed as universal diagnostic and prognostic biomarker in cancerpatients. PATIENTS AND METHODS: Cell-free DNA was isolated from 1 ml serum from patients with bladder cancer (BCA, n = 84), renal cell carcinoma (RCC, n = 33), and prostate cancer (CaP, n = 23), and compared with healthy individuals (n = 79). Quantitative real-time PCR was used to analyze the levels of a 79 bp (mtDNA-79), and 220 bp (mtDNA-220) fragment of the mitochondrial specific 16S-RNA. The mitochondrial DNA integrity (mtDNA-integrity) was defined as ratio of mtDNA-220 to mtDNA-79 fragments. RESULTS: In healthy controls, mtDNA-79 levels were increased in male volunteers; mtDNA-230 levels and mtDNA-integrity were correlated with age. Neither mtDNA levels nor mtDNA-integrity were correlated with age or gender in cancerpatients. Circulating mtDNA-79 (median 8.75 × 10(6) vs. 0.43 × 10(6) copies/ml) and mtDNA-230 (8.11 × 10(6) vs. 0.27 × 10(6) copies/ml) levels were significantly increased in cancerpatients and allowed sensitive (84%) and specific (97%) discrimination from healthy controls. mtDNA levels were unequally distributed among the different cancer entities (mtDNA-79: BCA 9.54 × 10(6) vs. RCC 6.69 × 10(6) vs. CaP 4.48 × 10(6) copies/ml; mtDNA-230: BCA 9.78 × 10(6) vs. RCC 6.74 × 10(6) vs. CaP 1.94 × 10(6) copies/ml). The mtDNA-integrity was increased in RCC and BCA patients compared to control subjects and CaP patients. Serum mtDNA-integrity was correlated with pathological stage in RCC and with tumor grade in BCA patients. CONCLUSION: Circulating mtDNA levels are associated with gender and age in healthy individuals, but not in cancerpatients. Quantification of circulating mtDNA may help identify patients with urologic malignancies.
Authors: M P Surmiak; M Hubalewska-Mazgaj; K Wawrzycka-Adamczyk; W Szczeklik; J Musiał; M Sanak Journal: Clin Exp Immunol Date: 2015-05-24 Impact factor: 4.330
Authors: Ailsa Sita-Lumsden; Claire E Fletcher; D Alwyn Dart; Greg N Brooke; Jonathan Waxman; Charlotte L Bevan Journal: Biomark Med Date: 2013-12 Impact factor: 2.851