Mitochondrial DNA 4977 bp Deletion in Chronic Cervicitis and Cervix Cancers

Abstract

Mitochondrial DNA (mtDNA) mutations have been implied in many diseases including cancer and inflammatory diseases. The aim of this study is to investigate the relationship between the 4977 bp deletion of the mtDNA and chronic cervicitis or cervix cancer in patients. The study included a group of patients with chronic cervicitis or cervix cancer, and a control group consisting of individuals without any cervical tissue disease. A total of 72 subjects in an East Turkish population were included in the study. Of these, 35 had chronic cervicitis, 21 had cervix cancer and 16 served as the control group. Isolation of mtDNA was performed from the tissues of these patients and then mtDNA deletions were studied using polymerase chain reaction (PCR). In the cancer groups, there were 9.5% heteroplasmic and homoplasmic deletions. There were no homoplasmic deletions in the cervicitis and control groups, but the frequencies of heteroplasmic deletions were 80.0 and 31.2%, respectively. Chronic inflammation leading to increased reactive oxygen species (ROS) may be the cause of the high mtDNA 4977 bp deletion frequencies in cancer and cervicitis. The older age of the cancer patient may suggest that ageing in addition to long time exposure to ROS may lead to deletions and subsequently cancer. This is the first study to investigate the relationship of the mtDNA 4977 bp deletion to chronic cervicitis and cervix cancer.

A comprehensive overview of mitochondrial DNA 4977-bp deletion in cancer studies

“…The mtDNA 4977 has also previously been investigated in several other cancers including skin cancer, 82,107,108 thyroid cancer, 88,109 lung cancer, 110 endometrial cancer, 111 cervix cancer, 112 as well as prostate cancer. 113…”

Mitochondrial Common Deletion, a Potential Biomarker for Cancer Occurrence, Is Selected against in Cancer Background: A Meta-Analysis of 38 Studies

“…The characteristics of each case-control study are listed in Table 1 . Of the 38 studies, sample sizes ranged from 7 to 130, in which nine studies focusing on breast cancer [25], [31]–[38], five studies focusing on hepatocellular carcinoma [39]–[43], four focusing on gastric cancer [38], [44]–[46], three focusing on colorectal cancer [25], [38], [47], three focusing on esophageal cancer [48]–[50], three focusing on oral cancer [51]–[53], two focusing on thyroid cancer [25], [54], two focusing on skin cancer [55], [56] and seven studies of other cancers (one endometrial carcinoma [57], one lung cancer [58], one Warthin’s cancer [59], one cervix cancer [60], one acute lymphoblastic leukemia [61], one prostate cancer [62] and one head and neck cancer [38]). Because some controls in two researches [25], [38] were shared by several cancers, it was defined as four studies (breast cancer, colorectal cancer, gastric cancer and head and neck cancer) and three studies (thyroid cancer, breast cancer and colorectal cancer) in the analysis stratified by cancer type but defined as one study in the overall analysis and stratification analysis by ethnicity, sample size, measurement method and DNA source.…”

Accumulation of mitochondrial dna microsatellite instability in malaysian patients with primary central nervous system tumors

“…mtDNA alterations in the form of point mutations, deletions, insertions, copy number changes and MSI, are believed to be hotspots of cancer research. Such genetic alterations in mtDNA have been widely reported in various human cancers (22,(35)(36)(37)47,62,63,67). Our previous studies have discovered a high frequency of somatic mtDNA mutations in brain tumor patients (46).…”