Myeloperoxidase polymorphism, menopausal status, and breast cancer risk: an update meta-analysis

Evaluation of Serum Paraoxonase, Myeloperoxidase, and HDL-Cholesterol Levels in Acute Myeloid Leukemia

Inflammation and oxidative stress play a significant role in the pathogenesis of acute myeloid leukemia. While myeloperoxidase carries pro-oxidant effects, HDL-cholesterol and paraoxonase have antioxidant properties. Therefore, we evaluated serum paraoxonase, myeloperoxidase, and HDL-cholesterol levels in cases with acute myeloid leukemia. Myeloperoxidase, paraoxonase, and HDL-cholesterol levels in 40 acute myeloid leukemia patients and 18 healthy individuals were determined. The relationship between these parameters and other prognostic factors, as well as their association with response to chemotherapy, was investigated. Myeloperoxidase levels were higher, while paraoxonase and HDL-cholesterol levels were lower in acute myeloid leukemia cases compared to the control group (p < 0.001, p < 0.001, p = 0.006, respectively). The myeloperoxidase level was significantly negatively correlated with paraoxonase and HDL-c levels (r =  - 0.64, p < 0.001; r =  - 0.27, p = 0.02, respectively). Paraoxonase level was positively correlated with HDL level (r = 0.34, p = 0.04). Lactate dehydrogenase level was negatively correlated with HDL-c and paraoxonase levels and positively correlated with myeloperoxidase level (r =  - 0.37, p = 0.019; r =  - 0.35, p = 0.04; r = 0.45, p = 0.03, respectively). Following complete remission induction treatment, cases with complete remission had lower myeloperoxidase levels and higher HDL-cholesterol and paraoxonase levels compared to other cases (p = 0.03, p = 0.01, p = 0.04, respectively). Myeloperoxidase levels are higher, while paraoxonase and HDL-cholesterol levels are lower in acute myeloid leukemia cases. The obtained findings emphasize the potential importance of inflammation and oxidative stress in the pathogenesis of acute myeloid leukemia. These parameters can be used as biomarkers for prognosis prediction and prediction of response to chemotherapy.

Properties and functions of myeloperoxidase and its role in ovarian cancer

Background: Elevated levels of myeloperoxidase in body fluids are increasingly being used as an indicator for the diagnosis of cancer. Aim of the study: The aim of this study was to review the literature on the physical and chemical properties of myeloperoxidase, its role in carcinogenesis, the role of tumor-associated neutrophils in cancer, and the role of myeloperoxidase in ovarian cancer. Material and methods: The research literature published between January 1999 and December 2019 was reviewed. The properties and role of myeloperoxidase in the development of ovarian cancer were selected from publications available in selected online databases, including MEDLINE, PubMed, Scopus, and Web of Science. Searches were performed using the following word combinations: “myeloperoxidase”, “ovarian cancer”, “reactive oxygen species”, “expression”, “polymorphism”, and “tumor-associated neutrophils”. Results: Thirty-five scientific articles were included in the final review. Of the 35 articles, 11 discussed the role of myeloperoxidase in carcinogenesis, and five discussed its role in the development of ovarian cancer. Conclusions: Elevated myeloperoxidase levels are associated with many types of cancer, including ovarian cancer. In the studied group of invasive ovarian tumors, up to 65% exhibited elevated levels of myeloperoxidase. Continued research on myeloperoxidase expression in ovarian cancer cells is vital and warranted.

Myeloperoxidase: Growing importance in cancer pathogenesis and potential drug target

Myeloperoxidase is a heme-peroxidase which makes up approximately 5% of the total dry cell weight of neutrophils where it is predominantly found in the primary (azurophilic) granules. Other cell types, such as monocytes and certain macrophage subpopulations also contain myeloperoxidase, but to a much lesser extent. Initially, the function of myeloperoxidase had been mainly associated with its ability as a catalyzer of reactive oxidants that help to clear pathogens. However, over the past years non-canonical functions of myeloperoxidase have been described both in health and disease. Attention has been specially focused on inflammatory diseases, in which an exacerbate infiltration of leukocytes can favor a poorly-controlled production and release of myeloperoxidase and its oxidants. There is compelling evidence that myeloperoxidase derived oxidants contribute to tissue damage and the development and propagation of acute and chronic vascular inflammation. Recently, neutrophils have attracted much attention within the large diversity of innate immune cells that are part of the tumor microenvironment. In particular, neutrophil-derived myeloperoxidase may play an important role in cancer development and progression. This review article aims to provide a comprehensive overview of the roles of myeloperoxidase in the development and progression of cancer. We propose future research approaches and explore prospects of inhibiting myeloperoxidase as a strategy to fight against cancer.

Association between MPO-463G > A polymorphism and cancer risk: evidence from 60 case-control studies

BACKGROUND

Though a number of studies have been conducted to explore the association between myeloperoxidase (MPO)-463G > A polymorphism and cancer risk, the results remain inconsistent. Therefore, we performed a meta-analysis to derive a more systematic estimation of this relationship.

METHOD

Relevant studies were searched by PubMed, EMBASE, CNKI, Google Scholar, Ovid, and Cochrane library prior to December 2015. The strength of the association between MPO-463G > A polymorphism and cancer risk was estimated by odds ratios (OR) with 95% confidence interval (95%CI). Cumulative analysis was used to evaluate the stability of results through time.

RESULTS

The current analysis consisted of 16,858 cases and 21,756 controls from 60 studies. Pooled results showed that MPO-463G > A polymorphism were associated with the overall decreased cancer susceptibility in all the genetic models included in this study (additive model: OR = 0.84, 95%CI = 0.76-0.94; allele genetic model: OR = 0.90, 95%CI = 0.840-0.954; recessive genetic model: OR = 0.89, 95%CI = 0.83-0.95). However, in the stratified analysis of cancer type, the significant results were only found in lung cancer (dominant model: OR = 0.93, 95%CI = 0.87-0.99) and digestive system cancer groups (dominant model: OR = 0.67 0.53-0.84; allele frequency model = 0.71, 95%CI = 0.57-0.87), but not in the blood system cancer or breast cancer group. When we further stratified the digestive system cancer group into digestive tract and digestive gland cancer groups, results showed a significant association between allele A of MPO-463G > A and digestive gland cancer in all the genetic models (allele frequency model: OR = 0.63, 95%CI = 0.40-0.99; additive model: OR = 0.41, 95%CI = 0.23-0.73; recessive model: OR = 0.51, 95%CI = 0.29-0.89; dominant model: OR = 0.58, 95%CI = 0.35-0.96), digestive tract cancers in allele frequency model (OR = 0.75, 95%CI = 0.59-0.95), and dominant model (OR = 0.72, 95%CI = 0.56-0.92). When stratified by ethnicity, results demonstrated that the genotype A might be a protect factor for both Caucasians and Asians. In group analysis according to source of controls, significant results were found in population from hospital in all the genetic models. In cumulative analysis, result of allele contrast showed a declining trend and increasingly narrower 95% overall, while the inclination toward non-significant association with lung cancer risk.

CONCLUSIONS

This meta-analysis suggested that MPO-463G > A polymorphism was associated with the overall reduced cancer susceptibility significantly. It might be a more reliable predictor of digestive system cancer instead of lung cancer, blood system cancer, and breast cancer. In cumulative analysis, the stable trend indicated that evidence was sufficient to show the association between MPO-463G > A polymorphism and cancer risk.

Involvement of myeloperoxidase gene polymorphism 463G>A in development of cervical squamous cell carcinoma

BACKGROUND

The myeloperoxidase (MPO) -463G&gt;A (rs2333227) polymorphism has been linked with increased susceptibility to the development of various malignancies. However, the data on the association of the MPO -463G&gt;A transition with cervical cancer remain inconsistent.

METHODS

Using high resolution melting analysis we genotyped this polymorphism in women with cervical squamous cell carcinoma (SCC) (n = 476) and controls (n = 493) from a Polish Caucasian population. Logistic regression analysis was used to adjust for the effect of confounders such as age, parity, oral contraceptive use, tobacco smoking, and menopausal status, and revealed that the MPO -463G&gt;A single nucleotide polymorphism (SNP) was associated with an increased risk of SCC.

RESULTS

The adjusted odds ratio (OR) for patients with the A/A genotype versus G/G genotype was 0.718 (95% CI 0.531-0.972, p = 0.0316). Stratified analyses between the MPO -463G&gt;A polymorphism and SCC risks demonstrated a protective role of the MPO -463G&gt;A SNP in patients with a positive history of parity and negative history of tobacco smoking. In patients with a positive history of parity, the age-adjusted OR for the A/A versus G/G genotype was 0.667 (95% CI 0.479-0.929, p = 0.0164). The age-adjusted OR for patients with a negative history of tobacco smoking for the A/A versus G/G genotype was 0.491 (95% CI 0.313-0.770, p = 0.0019).

CONCLUSIONS

Our study demonstrated that the MPO -463G&gt;A SNP may protect from SCC in women from Polish Caucasian populations.

Myeloperoxidase gene polymorphism predicts fibrosis severity in women with hepatitis C

Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P = 0.025 OR 2.25 CI 1.10-4.59 and P = 0.032 OR 2.32 CI 1.07-5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV.