Does Cryopreservation Uniformly Affect the Dna Fragmentation Rate of Spermatozoa of Men With Different States of Spermatogenesis? A Systematic Review and Meta-Analysis

Abstract

Cryotechnologies have become an integral part of infertility treatment methods. However, the question of the impact of cryopreservation on human sperm DNA fragmentation levels remains open. The aim was to conduct a systematic review and meta-analysis of studies on the effect of the cryopreservation method (a method of rapid cooling and vitrification) on the occurrence of DNA damage in spermatozoa of men with different states of spermatogenesis. The search was carried out in Medline, Embase, PubMed and Google Scholar databases. The results of 52 studies from 32 scientific papers were analysis in the present study. DNA damage in spermatozoa of men with different states of spermatogenesis was measured before and after cryopreservation using one of these methods: SCSA, SCD, TUNEL and Comet Assay. It was found that cryopreservation, regardless of the method used, leads to an increase of 7.73±2.04% in the DNA fragmentation rate of spermatozoa, regardless of the state of spermatogenesis of men. Cryopreservation increases normospermia sperm DNA fragmentation compared to pathospermia (SMD=8.76%, p<0.00001 and SMD=4.01%, p<0.00001, respectively). The greatest effect of cryopreservation on DNA fragmentation compared to fresh sperm was determined by the TUNEL method. Using this method, 8.08±2.38% of cells with the mentioned pathology were identified (SMD=8.08%, 95% CI 5.69 -10.46%, p<0.00001). Determining the degree of DNA damage of spermatozoa before their banking can be a useful marker of the effectiveness of their cryopreservation, as it has prognostic value regarding the effectiveness of infertility treatment by assisted reproductive technology methods.Results. A relationship between high-risk disease and male gender, multifocal lesions, localization in the lower third of the thyroid lobe, superficial location of the tumor, and stromal fibrosis was showing in Sak S. D.`s study. According to the results of studies, size of tumor larger than 1.0 cm and multifocal lesions can be considered an indicator of the aggressive course of PTC. AIT complicates the cytological diagnosis of nodal masses. Cellular atypia, anisonucleosis, and pleomorphism are observed in both AIT and PTC, so differential diagnosis in the case of a combination of these pathologies is more difficult. The basis for this relationship is the molecular, hormonal and histopathological similarity of these diseases. Galectin-3 is a regulator of normal cell proliferation, and its overexpression leads to malignant cell transformation and metastasis. The neoplastic transformation of benign tissue is a complex process influenced by numerous factors. Humoral mechanisms of cancer development are associated with the IgG4 subclass. Regulatory Treg cells are a subgroup of CD4+ cells that suppress the immune response, playing an important role in avoiding the host's antitumor immune response. It is reported that a decrease in CD4+ leads to oncological transformation. The BRAF mutation has also been shown to cause overexpression of many other molecular tumour markers, such...