Deoxyribonuclease activity in biological fluids of healthy donors and cancer patients

Abstract

Integral activity of neutral deoxyribonucleases in the plasma and urine or donors, patients with benign prostatic hyperplasia, and patients with stomach and prostatic cancer was studied by IFA based on hydrolysis of DNA fragment modified with haptene molecules. In donors plasma deoxyribonuclease activity was 0.16+/-0.04, urinary activity 1.49+/-1.41 act. U/ml. In patients with benign prostatic hyperplasia and malignant tumors the integral activity of blood deoxyribonucleases was significantly below the normal, and in tumors it did not correlate with tumor size and disease stage. A significant correlation between blood and urinary deoxyribonuclease activities was detected.

Detection of Methylated Septin 9 in Tissue and Plasma of Colorectal Patients with Neoplasia and the Relationship to the Amount of Circulating Cell-Free DNA

“…The discordance between mSEPT9 levels in tissue and plasma in the adenoma group suggests that additional factors than tissue methylation levels are important parameters that determine the amount of DNA from cancer or precursor lesions to be detectable in plasma. Our hypothesis is that poor vascularisation, lower numbers of apoptotic or necrotic cells [47] , [48] and additional factors such as high activity of DNase in plasma [49] – [51] are responsible for lower levels of DNA released into the blood stream in adenomas as compared to cancer and that this may be responsible for the different detection levels of SEPT9 in plasma.…”

Extracellular DNA promotes colorectal tumor cell survival after cytotoxic chemotherapy

“…Free DNA has been identified in the serum of patients with a variety of cancers, where it has been shown to inversely correlate with survival. [12][13][14][15][16] DAMPs such as HMGB1, histones, S100, uric acid, and nucleic acids mediate their biology through a family of receptors known as PRRs, including the TLRs, the RAGE, cytoplasmic Nod-like receptors, and the RNA helicase family of receptors. 3,17 Until recently it was believed that the expression of PRRs was limited to cells of the innate immune system; however, a growing body of literature supports expression on epithelial and tumor cells.…”

Implementing routine monitoring for nuclease contamination of equipment and consumables into the quality Management system of a laboratory

“…However, studies using this medium have consistently shown that PBMC viability is not impaired with CryoStor CS10 compared to alternative cryopreservation media [ 18 , 19 ]. In addition, extracellular DNases are present in the plasma of both healthy and diseased individuals, so PBMCs likely have an inherent resilience to low levels of extracellular DNase [ [20] , [21] , [22] , [23] ]. We are therefore confident that no changes are required to our PBMC isolation protocol.…”