CENP-A regulates chromosome segregation during the first meiosis of mouse oocytes

Anticentromere antibodies are the most potent antinuclear antibodies in reducing live birth outcomes after ICSI

RESEARCH QUESTION

How, and to what extent, do anticentromere antibodies (ACA) reduce live birth outcomes after ICSI?

STUDY DESIGN

Retrospective cohort study of infertile women aged 30-43 years who underwent ICSI between September 2016 and March 2021. Women with a history or current diagnosis of symptomatic connective tissue disease were excluded. Immunofluorescence staining detected antinuclear antibodies (ANA). Staining pattern and titre (cut-off, 1:160) were used to divide infertile women into three groups: positive for ACA (ACA+) (n = 28); positive for ANA other than ACA (ANA+) (n = 77); and negative for both ACA and ANA (control) (n = 3723).

RESULTS

Cumulative live birth rate (CLB) was lowest in ACA+ (7%, 31% and 46% in ACA+, ANA+ and control, respectively) (ACA+ versus control, P < 0.0001; ACA+ versus ANA+, P = 0.011; ANA+ versus control, P = 0.012). A small impairment in meiosis I and a larger impairment in meiosis II, fertilization and embryo cleavage caused the decrease. Multiple pronuclei formation increased (RR versus control, 5.33; 95% CI 4.26 to 6.65) and good-quality blastocyst development decreased (RR 0.34; 95% CI 0.22 to 0.53). Multiple logistic regression analysis showed that ACA was associated with CLB outcome (OR 0.08, 95% CI 0.02 to 0.36); the other four ANA staining patterns were not.

CONCLUSIONS

The effect of ACA on live birth outcomes is strongest after ICSI among ANA, primarily through the impairment of meiosis II and subsequent stages. Repeated ICSI failure and eggs with multiple pronuclei may warrant specific testing for ACA.

Preimplantation embryo gene expression: 56 years of discovery, and counting

The biology of preimplantation embryo gene expression began 56 years ago with studies of the effects of protein synthesis inhibition and discovery of changes in embryo metabolism and related enzyme activities. The field accelerated rapidly with the emergence of embryo culture systems and progressively evolving methodologies that have allowed early questions to be re-addressed in new ways and in greater detail, leading to deeper understanding and progressively more targeted studies to discover ever more fine details. The advent of technologies for assisted reproduction, preimplantation genetic testing, stem cell manipulations, artificial gametes, and genetic manipulation, particularly in experimental animal models and livestock species, has further elevated the desire to understand preimplantation development in greater detail. The questions that drove enquiry from the earliest years of the field remain drivers of enquiry today. Our understanding of the crucial roles of oocyte-expressed RNA and proteins in early embryos, temporal patterns of embryonic gene expression, and mechanisms controlling embryonic gene expression has increased exponentially over the past five and a half decades as new analytical methods emerged. This review combines early and recent discoveries on gene regulation and expression in mature oocytes and preimplantation stage embryos to provide a comprehensive understanding of preimplantation embryo biology and to anticipate exciting future advances that will build upon and extend what has been discovered so far.

A Comprehensive Bioinformatics Analysis of UBE2C in Cancers

Ubiquitination is one of the main post-translational modification of proteins. It plays key roles in a broad range of cellular functions, including protein degradation, protein interactions, and subcellular location. In the ubiquitination system, different proteins are involved and their dysregulation can lead to various human diseases, including cancers. By using data available from the Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) databases, we here show that the ubiquitin conjugating enzyme, E2C (UBE2C), is overexpressed in all 27 cancers we investigated. UBE2C expression is significantly higher in late-stage tumors, which might indicate its involvement in tumor progression and invasion. This study also revealed that patients with higher UBE2C levels showed a shorter overall survival (OS) time and worse OS prognosis. Moreover, our data show that UBE2C higher-expression leads to worse disease-free survival prognosis (DFS), indicating that UBE2C overexpression correlates with poor clinical outcomes. We also identified genes with positive correlations with UBE2C in several cancers. We found a number of poorly studied genes (family with sequence similarity 72-member D, FAM72D; meiotic nuclear divisions 1, MND1; mitochondrial fission regulator 2, MTFR2; and POC1 centriolar protein A, POC1A) whose expression correlates with UBE2C. These genes might be considered as new targets for cancers therapies since they showed overexpression in several cancers and correlate with worse OS prognosis.