The interplay between XPG-Asp1104His polymorphism and reproductive risk factors elevates risk of breast cancer in Tanzanian women: A multiple interaction analysis

Genome-wide association study identifies common variants associated with breast cancer in South African Black women

Genome-wide association studies (GWAS) have characterized the contribution of common variants to breast cancer (BC) risk in populations of European ancestry, however GWAS have not been reported in resident African populations. This GWAS included 2485 resident African BC cases and 1101 population matched controls. Two risk loci were identified, located between UNC13C and RAB27A on chromosome 15 (rs7181788, p = 1.01 × 10-08) and in USP22 on chromosome 17 (rs899342, p = 4.62 × 10-08). Several genome-wide significant signals were also detected in hormone receptor subtype analysis. The novel loci did not replicate in BC GWAS data from populations of West Africa ancestry suggesting genetic heterogeneity in different African populations, but further validation of these findings is needed. A European ancestry derived polygenic risk model for BC explained only 0.79% of variance in our data. Larger studies in pan-African populations are needed to further define the genetic contribution to BC risk.

Probable Molecular Targeting of Inhibitory Effect of Carvacrol-Loaded Bovine Serum Albumin Nanoparticles on Human Breast Adenocarcinoma Cells

OBJECTIVE

To entrap carvacrol (CAR) in bovine serum albumin nanoparticles (BSANPs) to form CAR-loaded BSANPs (CAR@BSANPs) and to explore the anti-cancer effects in breast adenocarcinoma cells (MCF-7 cells) treated with CAR and CAR@BSANPs.

METHODS

A desolvation method was used to synthesize BSANPs and CAR@BSANPs. The BSANPs and CAR@BSANPs were characterized by several physicochemical methods, including visual observation, high-resolution field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and high-performance liquid chromatography. MCF-7 cells were used and analyzed after 24 h of exposure to CAR and CAR@BSANPs at half-maximal inhibitory concentration. The anti-proliferative, apoptotic, reactive oxygen species (ROS), and nitric oxide (NO) scavenging activity as well as gene expression analysis were investigated by the cell viability assay, phase-contrast microscopy, 2',7'-dichlorofluorescein-diacetate assay, Griess-Illosvoy colorimetric assay, and quantitative real-time polymerase chain reaction, respectively.

RESULTS

CAR and CAR@BSANPs showed anti-proliferative, apoptotic, ROS generation, and NO scavenging effects on MCF-7 cells. Expression profile of B-cell lymphoma 2-like 11 (BCL2L11), vascular endothelial growth factor A (VEGFA), hypoxia inducible factor factor-1α (HIF1A), BCL2L11/apoptosis regulator (BAX), and BCL2L11/Bcl2 homologous antagonist/killer 1 (BAK1) ratios revealed downregulated genes; and BAX, BAK1, and CASP8 were upregulated by CAR and CAR@BSANPs treatment. In vitro anticancer assays of the CAR and CAR@BSANPs showed that CAR@BSANPs demonstrated higher therapeutic efficacy in the MCF-7 cells than CAR.

CONCLUSIONS

CAR and CAR@BSANPs affect gene expression and may subsequently reduce the growth and proliferation of the MCF-7 cells. Molecular targeting of regulatory genes of the MCF-7 cells with CAR and CAR@BSANPs may be an effective therapeutic strategy against breast cancer.

Cancer genetic mutation prevalence in sub-Saharan Africa: A review of existing data

BACKGROUND

Cancer represents a leading cause of death worldwide. Germline mutations in several genes increase the risk of developing several cancers, including cancers of the breast, ovary, pancreas, colorectum, and melanoma. An understanding of the population prevalence of pathogenic germline variants can be helpful in the design of public health interventions, such as genetic testing, which has downstream implications for cancer screening, prevention, and treatment. While population-based studies of pathogenic germline variants exist, most such studies have been conducted in White populations. Limited data exist regarding the prevalence of germline mutations within sub-Saharan African populations.

MATERIALS AND METHODS

We identified countries defined as sub-Saharan Africa by the World Bank and conducted a scoping literature review using PubMed. For each country, we identified and summarized studies that focused on the prevalence of germline genetic mutations with sample sizes >10 and in a population directly from sub-Saharan Africa, either with or without diseases associated with the relevant genetic mutations. Studies that evaluated the prevalence of somatic or likely benign variants were excluded.

RESULTS

Within the 48 countries in sub-Saharan Africa, we identified 34 studies which meet the inclusion criteria. Twenty studies were conducted in South Africa, Nigeria, or Burkina Faso; four countries had more than two published papers. We found that 33 of 48 countries in sub-Saharan Africa lacked any genetic studies. Notably, there has been an increase in relevant studies starting in 2020. Importantly, of the 34 studies identified, 29 included data on BRCA1 or BRCA2. Data on the prevalence of mutations contributing to familial cancer syndromes other than BRCA1 and BRCA2 was limited.

CONCLUSIONS

While some progress has been made towards understanding the prevalence of germline mutations in cancer susceptibility genes, the characterization of genetic mutations among sub-Saharan African populations remains strikingly incomplete. Given the genetic diversity in the region, there remains a great need for large-scale, population-based studies to understand the prevalence of germline pathogenic variants and adequately capture all the subpopulations in this part of the world.

Association of lncRNA H19 polymorphisms with cancer susceptibility: An updated meta-analysis based on 53 studies

The association between polymorphisms in lncRNA H19 and cancer susceptibility remains to be inconsistent. This study aimed to provide a more precise estimation of the relationship between lncRNA H19 polymorphisms and the risk of cancer based on all available published studies. 53 studies encompassing 32,376 cases and 43,659 controls were included in our meta-analysis by searching the Pubmed, Embase, Web of Science, WanFang, and China National Knowledge Infrastructure databases. Pooled ORs and their 95% CIs were used to estimate the strength between the SNPs in H19 (rs217727, rs2839698, rs2107425, rs3024270, rs2735971, rs3741216, and rs3741219) and cancer susceptibility. The results showed that H19 rs2839698 polymorphism was associated with increased cancer risk in all participants under three genetic models. However, no significant association was identified between the other six SNPs as well as an overall cancer risk. Stratification by ethnicity showed that rs2839698 mutation indicated to be an important hazardous factor for the Asian population. While rs2107425 mutation had a protective effect on the Caucasian population. Stratification by cancer type identified that rs217727 mutation was linked to increased susceptibility to oral squamous cell carcinoma, lung cancer, and hepatocellular carcinoma; whereas rs2839698 mutation was associated with an elevated risk of hematological tumor and digestive system tumor (p < 0.05). Besides, the rs2735971 mutation was connected with the digestive system tumor. In summary, the rs217727, rs2839698, rs2107425 and rs2735971 polymorphisms in H19 have associations with cancer susceptibility.