Search

IntroductionAs of 2020, breast cancer has emerged as the predominant cause of cancer incidence globally. Anthracycline-based chemotherapy serves as a crucial element in the treatment regimen for breast cancer. However, these anthracycline-based drugs are associated with cardiac toxicity. This study represents the first clinical quantitative analysis aimed at accurately determining the incidences of arrhythmia and abnormal electrocardiogram (ECG) changes, thereby providing valuable data to bolster clinical drug usage and monitoring.MethodsA systematic search was conducted across multiple databases including CNKI, VIP, Wanfang, PubMed, Embase, Web of Science, and the Cochrane Library. The incidence of combined arrhythmias in breast cancer patients and the associated heterogeneity were calculated using either a random effect model or a fixed effect model. Statistical analysis was performed using STATA16.ResultsThe study encompassed a total of 37 articles, which included 5705 breast cancer patients undergoing anthracycline treatment. Among these patients, 2257 developed arrhythmias. The meta-analysis revealed that the incidence of anthracycline-associated arrhythmias and abnormal ECG changes in breast cancer patients was 0.41 (0.37, 0.44). Subgroup analysis indicated that the incidence of ST-T segment change was 0.19 (0.15, 0.23), the incidence of conduction block was 0.04 (0.02, 0.05), the incidence of premature beats was 0.09 (0.07, 0.11), and the incidence of atrial fibrillation was 0.04 (0.00, 0.12). Additional results are presented in Table 3.ConclusionThis pioneering study accurately assesses the incidence of arrhythmias in breast cancer patients treated with anthracyclines. The findings provide clinicians with valuable insights into understanding and managing the cardiac toxicity associated with such treatment. Moreover, this study lays the foundation for future research exploring the mechanisms underlying these arrhythmias and potential preventative strategies.

ObjectiveCoronary artery disease (CAD) is a leading cause of death worldwide. Many studies in China and abroad have reported an association between the expression level of microRNA-155 and CAD; however, the results remain controversial. We aimed to comprehensively investigate this association based on a meta-analysis.MethodsWe first systematically searched eight Chinese and English databases, including China National Knowledge Infrastructure, Wanfang, China Science and Technology Journal Database, PubMed, Web of Science, Embase, Google Scholar, and Cochrane Library, to identify studies concerning the relationship between microRNA-155 levels and CAD published before February 7, 2021. The quality of the literature was assessed by the Newcastle-Ottawa Scale (NOS). Meta-analysis was performed using a random-effects model to calculate the standard mean difference with a 95% confidence interval (CI).ResultsSixteen articles with a total of 2069 patients with CAD and 1338 controls were included. All the articles were of high quality according to the NOS. The meta-analysis showed that the mean level of microRNA-155 was significantly lower in patients with CAD than in controls. Based on subgroup analyses, the level of microRNA-155 in the plasma of CAD patients and in acute myocardial infarction (AMI) patients was significantly lower than that in controls, whereas this level in CAD patients with mild stenosis was significantly higher than that in controls.ConclusionOur study indicates that the expression level of circulating microRNA-155 in patients with CAD is lower than that in a non-CAD group, suggesting a new possible reference index for the diagnosis and monitoring of patients with CAD.

Current knowledge of the genetic architecture of key reproductive events across the female life course is largely based on association studies of European descent women. The relevance of known loci for age at menarche (AAM) and age at natural menopause (ANM) in diverse populations remains unclear. We investigated 32 AAM and 14 ANM previously-identified loci and sought to identify novel loci in a trans-ethnic array-wide study of 196,483 SNPs on the MetaboChip (Illumina, Inc.). A total of 45,364 women of diverse ancestries (African, Hispanic/Latina, Asian American and American Indian/Alaskan Native) in the Population Architecture using Genomics and Epidemiology (PAGE) Study were included in cross-sectional analyses of AAM and ANM. Within each study we conducted a linear regression of SNP associations with self-reported or medical record-derived AAM or ANM (in years), adjusting for birth year, population stratification, and center/region, as appropriate, and meta-analyzed results across studies using multiple meta-analytic techniques. For both AAM and ANM, we observed more directionally consistent associations with the previously reported risk alleles than expected by chance (p-valuesbinomial≤0.01). Eight densely genotyped reproductive loci generalized significantly to at least one non-European population. We identified one trans-ethnic array-wide SNP association with AAM and two significant associations with ANM, which have not been described previously. Additionally, we observed evidence of independent secondary signals at three of six AAM trans-ethnic loci. Our findings support the transferability of reproductive trait loci discovered in European women to women of other race/ethnicities and indicate the presence of additional trans-ethnic associations both at both novel and established loci. These findings suggest the benefit of including diverse populations in future studies of the genetic architecture of female growth and development.

Rodent genomic alignment sequences support a 2-exon model for muscarinic M4 receptor. Using this model a novel N-terminal extension was discovered in the human muscarinic acetylcholine M4 receptor. An open reading frame was discovered in the human, mouse and rat with a common ATG (methionine start codon) that extended the N-terminus of the muscarinic acetylcholine M4 receptor subtype by 155 amino acids resulting in a longer variant. Transcriptional evidence for this splice variant was confirmed by RNA-Seq and RT-PCR experiments performed from human donor brain prefrontal cortices. We detected a human upstream exon indicating the translation of the mature longer M4 receptor transcript. The predicted size for the longer two-exon M4 receptor splice variant with the additional 155 amino acid N-terminal extension, designated M4L is 69.7 kDa compared to the 53 kDa canonical single exon M4 receptor (M4S). Western blot analysis from a mammalian overexpression system, and saturation radioligand binding with [3H]-NMS (N-methyl-scopolamine) demonstrated the expression of this new splice variant. Comparative pharmacological characterization between the M4L and M4S receptors revealed that both the orthosteric and allosteric binding sites for both receptors were very similar despite the addition of an N-terminal extension. [ABSTRACT FROM AUTHOR]