Background: Growing prevalence and aggressiveness of breast cancer (BC) among East African women strongly indicate that the genetic risk factor implicated in the etiology of the disease may have a key role. Germline pathogenic variants in BRCA1 and BRCA2 (BRCA1/2) are known to increase the lifetime risk of BC. This study investigated the prevalence and spectrum of germline single nucleotide variant/insertion and deletion (SNV/indel), and copy number variations (CNVs) in BRCA1/2 among Tanzanian BC patients, and evaluated the associations of identified variants with patient's socio‐demographic and histopathological characteristics.Methods: One hundred BC patients were examined for BRCA1/2 variants using next‐generation sequencing (NGS). Sanger sequencing and multiplex ligation‐dependent probe amplification (MLPA) assay were performed for the confirmation of SNV/indel and CNVs, respectively.Results: Six germline SNV/indel pathogenic variants were detected from six unrelated patients. Five of these variants were identified in BRCA1, and one in BRCA2. We also identified, in one patient, one variant of uncertain clinical significance (VUS). CNV was not detected in any of the BC patients. Furthermore, we found that in our cohort, BRCA1/2 variant carriers were triple‐negative BC patients (p = 0.019).Conclusions: Our study provides first insight into BC genetic landscape by the use of NGS in the under‐represented East African Tanzanian populations. Our findings support the importance of genetic risk factors in BC etiology in Tanzania and showed a relatively high overall prevalence (6%) of germline BRCA1/2 pathogenic variants in BC patients. Therefore, our results indicate that BRCA1/2 pathogenic variants may well contribute to BC incidence in Tanzania. Thus, the identification of frequent variants in BRCA1/2 genes will enable implementation of rapid, inexpensive population‐specific BRCA1/2 genetic testing, particularly for triple‐negative BC patients known for their high prevalence in Tanzania. This will, in turn, greatly contributes to provide effective therapeutic strategies.
Visceral fat deposition and its associated atherogenic complications are mediated by glucocorticoids. Cardiac visceral fat comprises mediastinal adipose tissue (MAT) and epicardial adipose tissue (EAT), and MAT is a potential biomarker of risk for obese patients.
27 December 2023 in Journal of Cellular and Molecular Medicine
Antisense Noncoding RNA in the INK4 Locus (ANRIL) is the prime candidate gene at Chr9p21, the well‐defined genetic risk locus associated with coronary artery disease (CAD). ANRIL and its transcript variants were investigated for the susceptibility to CAD in adipose tissues (AT) and peripheral blood mononuclear cells (PBMCs) of the study group and the impact of 9p21.3 locus mutations was further analysed. Expressions of ANRIL, circANRIL (hsa_circ_0008574), NR003529, EU741058 and DQ485454 were detected in epicardial AT (EAT) mediastinal AT (MAT), subcutaneous AT (SAT) and PBMCs of CAD patients undergoing coronary artery bypass grafting and non‐CAD patients undergoing heart valve surgery. ANRIL expression was significantly upregulated, while the expression of circANRIL was significantly downregulated in CAD patients. Decreased circANRIL levels were significantly associated with the severity of CAD and correlated with aggressive clinical characteristics. rs10757278 and rs10811656 were significantly associated with ANRIL and circANRIL expressions in AT and PBMCs. The ROC‐curve analysis suggested that circANRIL has high diagnostic accuracy (AUC: 0.9808, cut‐off: 0.33, sensitivity: 1.0, specificity: 0.88). circANRIL has high diagnostic accuracy (AUC: 0.9808, cut‐off: 0.33, sensitivity: 1.0, specificity: 0.88). We report the first data demonstrating the presence of ANRIL and its transcript variants expressions in the AT and PBMCs of CAD patients. circANRIL having a synergetic effect with ANRIL plays a protective role in CAD pathogenesis. Therefore, altered circANRIL expression may become a potential diagnostic transcriptional biomarker for early CAD diagnosis.
The immune system plays an important role in protecting the body against malignancy. During cancer immunoediting, the immune system can recognize and keep checking the tumor cells by down-expression of some self-molecules or by increasing expression of some novel molecules. However, the microenvironment created in the course of cancer development hampers the immune ability to recognize and destroy the transforming cells. Human Leukocyte Antigen G (HLA-G) is emerging as immune checkpoint molecule produced more by cancer cells to weaken the immune response against them. HLA-G is a non-classical HLA class I molecule which is normally expressed in immune privileged tissues as a soluble or membrane-bound protein. HLA-G locus is highly polymorphic in the non-coding 3′ untranslated region (UTR) and in the 5′ upstream regulatory region (5′ URR). HLA-G expression is controlled by polymorphisms located in these regions, and several association studies between these polymorphic sites and disease predisposition, response to therapy, and/or HLA-G protein expression have been reported. Various polymorphisms are demonstrated to modulate its expression and this is increasingly finding more significance in cancer biology. This review focuses on the relevance of the HLA-G gene and its polymorphisms in cancer development. We highlight population genetics of HLA-G as evidence to espouse the need and importance of exploring potential utility of HLA-G in cancer diagnosis, prognosis and immunotherapy in the currently understudied African population.
Background: Reproductive history and genetics are well‐known risk factors of breast cancer (BC). Little is known about how these factors interact to effect BC. This study investigated the association of ten polymorphisms in DNA repair genes with BC susceptibility in the Tanzanian samples and further analyzed the association between reproductive risk factors and disease riskMethods: A hospital‐based case–control study in 263 histopathological confirmed BC patients and 250 age‐matched cancer‐free controls was carried out. Allelic, genotypic, and haplotype association analyses were executed. Also, multifactor dimensionality reduction (MDR), and interaction dendrogram approaches were performed.Results: The frequency of genotypic and allelic variants of XRCC1‐Arg399Gln (rs25487), XRCC2‐Arg188His (rs3218536), XRCC3‐Thr241Met (rs861539), XPG‐Asp1104His (rs17655), and MSH2‐Gly322Asp (rs4987188) were significantly different between the groups (p < 0.05). Moreover, XRCC1‐Arg399Gln (rs25487), XRCC3‐Thr241Met (rs861539), and XPG‐Asp1104His (rs17655) were associated with the increased risk of BC in co‐dominant, dominant, recessive, and additive genetic‐inheritance models (p < 0.05). XRCC1‐Arg/Gln genotype indicated a 3.1‐fold increased risk of BC in pre‐menopausal patients (p = 0.001) while XPG‐His/His genotype showed a 1.2‐fold increased risk in younger BC patients (<40 years) (p = 0.028). Asp/His+His/His genotypes indicated a 1.3‐fold increased risk of BC in PR+ patients and a 1.1‐fold decreased risk of BC in luminal‐A patients (p = 0.014, p = 0.020, respectively). MDR analysis revealed a positive interaction between BC and the XPG‐Asp1104His (rs17655) together with family history of cancer in the first‐degree relatives. Dendrogram analysis indicated that the XPG‐Asp1104His (rs17655) and family history of cancer in first‐degree relatives were significantly synergistic and might be associated with an elevated risk of BC in Tanzania.Conclusions: The XPG‐Asp1104His (rs17655) might exert both independent and interactive effects on BC development in the Tanzanian women.
7 January 2025 in Canadian Journal of Infectious Diseases and Medical Microbiology
West Nile Virus (WNV) infection represents a major global public health challenge. Even though most of the patients are asymptomatic, some cases progress to critical condition which may be fatal. Diagnosis traditionally relies on serological methods, but their limitations, including cross‐reactivity, highlight the need for alternative approaches. Here, we present the development and validation of a novel RT‐qPCR assay for precise and rapid detection of WNV RNA in urine, emerging as a promising specimen due to its noninvasive collection and high viral load. The assay demonstrates high efficiency and sensitivity, with a detection limit comparable to commercially available kits. This study highlights the importance of in‐house kit design as a diagnostic tool in regions affected by emerging tropical infections, such as WNV, exemplified Cyprus. It emphasizes the critical role of low‐cost, early detection with high sensitivity and specificity in infection control and surveillance efforts.