microRNA miR-133a as a Biomarker for Doxorubicin-Induced Cardiotoxicity in Women with Breast Cancer: A Signaling Pathway Investigation.

Cardiovascular toxicity is the main adverse effect of Doxorubicin (DOX) in cancer patients. microRNAs (miRNAs) are promising biomarkers to identify cardiac injury induced by DOX in breast cancer patients during the subclinical phase. Using RT-qPCR, we compared the expression of circulating miR-208a5p, miR-133a, miR-499a5p, miR-15a, miR-133b, and miR-49a3p in serum samples from DOX-induced cardiotoxicity (case) compared to the non-cardiotoxicity group (control). To further explore the potential roles of these circulating miRNA in cardiotoxicity, we searched the miRTarBase for experimentally validated miRNA-target interactions and performed a functional enrichment analysis based on those interactions. miR-133a was significantly upregulated in case compared to control group. The most relevant pathway regulated by miR-133a was ErbB2 signaling, whose main genes involved are EGFR, ERBB2, and RHOA, which are possibly downregulated by miR133a. The other miRNAs did not show significant differential expression when compared on both groups. The data suggest that miR-133a is associated with DOX-based cardiotoxicity during chemotherapy in breast cancer patients through ErbB2 signaling pathway. Moreover, miR-133a may be a future marker of DOX-induced cardiotoxicity in women with breast cancer.

microRNAs associated to anthracycline-induced cardiotoxicity in women with breast cancer: A systematic review and pathway analysis.

BACKGROUND: Cardiotoxicity is a common and serious adverse effect of anthracycline therapy in breast cancer patients. The current criteria for cardiotoxicity are based on imaging and cardiac biomarkers. However, there is a need for new biomarkers to help with early diagnosis. MicroRNAs (miRNAs) are small non-coding RNA molecules that play an important role in the regulation of gene expression. Several miRNAs have been associated with cardiovascular diseases and are biomarkers under investigation for cancer treatment-related cardiotoxicity. METHODS: We performed a systematic literature search of Medline/PubMed, Cochrane Central Register of Controlled Trials, Scopus, Lilacs, Web of Science and Embase, until April 2020. Cohort studies that reported miRNA biomarkers in breast cancer patients with anthracycline-induced cardiotoxicity and non-cardiotoxicity patients were included. Moreover, we searched the miRTarBase for experimentally validated miRNA-target interactions. RESULTS: Among the 209 studies retrieved, five fulfilled the inclusion criteria. Let-7f, miR-1, miR-20a, miR-126 and miR-210 were validated in two population-based cohorts. The pro-angiogenic miRNAs let-7f, miR-20a, miR-126 and miR-210 were significantly down-regulated in epirubicin-cardiotoxicity when compared to the non-cardiotoxicity group. miR-1 has been shown to provide diagnostic and prognostic information in the setting of myocardial infarction, but changes in its levels are controversial in doxorubicin-treated breast cancer patients with cardiotoxicity. Reactome pathways relevant to cardiotoxicity were found from the target genes for let-7f, miR-1, miR-20a, miR-126 and miR-210 at miRTarBase. CONCLUSION: The data suggest that let-7f, miR-1, miR-20a, miR-126 and miR-210 are associated with anthracycline-based cardiotoxicity during chemotherapy in breast cancer patients.

Functional polymorphisms of BCL11A and HBS1L-MYB genes affect both fetal hemoglobin level and clinical outcomes in a cohort of children with sickle cell anemia.

Fetal hemoglobin (HbF) ameliorates clinical severity of sickle cell anemia (SCA). The major loci regulating HbF levels are HBB cluster, BCL11A, and HMIP-2 (HBS1L-MYB). However, the impact of noncoding single-nucleotide polymorphisms (SNPs) in these loci on clinical outcomes and their functional role on regulating HbF levels should be better elucidated. Therefore, we performed comprehensive association analyses of 14 noncoding SNPs in five loci with HbF levels and with clinical outcomes in a cohort of 250 children with SCA from Southeastern Brazil, and further performed functional annotation of these SNPs. We found SNPs independently associated with HbF levels: rs4671393 in BCL11A (ß-coefficient = 0.28), rs9399137 in HMIP-2A (ß-coefficient = 0.16), and rs4895441 in HMIP-2B (ß-coefficient = 0.15). Patients carrying minor (HbF-boosting) alleles for rs1427407, rs93979137, rs4895441, rs9402686, and rs9494145 showed reduced count of reticulocytes (p < 0.01), while those carrying the T allele of rs9494145 showed lower white blood cell count (p = 0.002). Carriers of the minor allele for rs9402686 showed higher peripheral saturation of oxygen (p = 0.002). Patients carrying minor alleles in BCL11A showed lower risk of transfusion incidence rate ratio (IRR ≥ 1.3; p < 0.0001). This effect was independent of HbF effect (p = 0.005). Carriers of minor alleles for rs9399137 and rs9402686 showed lower risk of acute chest syndrome (IRR > 1.3; p ≤ 0.01). Carriers of the reference allele for rs4671393 showed lower risk of infections (IRR = 1.16; p = 0.01). In conclusion, patients carrying HbF-boosting alleles of BCL11A and HMIP-2 were associated with milder clinical phenotypes. Higher HbF concentration may underlie this effect.

Effect of genetic polymorphisms of vascular endothelial growth factor on left ventricular hypertrophy in patients with systemic hypertension.

Vascular endothelial growth factor (VEGF) is a cytokine involved in angiogenesis and upregulated during adaptive heart hypertrophy. Downregulation of VEGF seems to trigger the transition from adaptive to dilated cardiac hypertrophy. We investigated for the first time whether 3 clinically relevant polymorphisms in the VEGFA gene are associated with altered echocardiographic parameters in hypertensive patients. We determined genotypes for 3 polymorphisms in VEGFA promoter in 179 hypertensive patients and 169 healthy controls: g.-2578C>A (rs699947), g.-1154G>A (rs1570360), and g.-634G>C (rs2010963). Although the variant genotypes of the g.-634G>C (GC + CC) were associated with reduced left ventricular mass index (p = 0.030), the variant genotypes for the g.-1154G>A (GA + AA) were associated with reduced ejection fraction (p = 0.008). In addition, we found that VEGFA haplotypes were associated with altered ejection fraction (p = 0.024). The AAG haplotype was associated with reduced ejection fraction (p = 0.006), whereas the AGG haplotype was associated with increased ejection fraction (p = 0.010). Our results suggest that VEGF polymorphisms affect cardiac remodeling. Genotypes for VEGFA polymorphisms can be useful to help to identify hypertensive patients at greater intrinsic risk for heart failure.

Polymorphisms and haplotypes in candidate genes related to angiogenesis and endothelial dysfunction in preeclampsia.

Valenzuela and colleagues have recently reviewed some polymorphisms in important candidate genes involved in different pathogenic mechanisms related to preeclampsia (PE) and concluded that various studies in different populations have identified maternal polymorphisms associated with PE. However, we would like to contribute to some studies regarding candidate genes related to angiogenesis and endothelial dysfunction in PE performed in the Brazilian population. Specifically, genotypes and haplotypes formed by polymorphisms of VEGF, eNOS and MMP-9, along with an example of the interaction among these genes in the prediction of PE. Our suggestions may provide additional information with clinical relevance to PE susceptibility.

Matrix metalloproteinase (MMP)-2 and MMP-9 polymorphisms and haplotypes as disease biomarkers.

Chaudhary and colleagues observed associations of matrix metalloproteinase (MMP)-2 (-1306C/T) and MMP-9 (-1562C/T) promoter polymorphisms with head and neck squamous cell carcinoma (HNSCC), but not with oral submucous fibrosis (OSMF) in an Indian population. We suggest that they could carry out a haplotype analysis with their data on MMP-2 genotypes (-1306C/T and -168G/T) and that they consider genotyping the microsatellite -90 (CA)(14-24) in the MMP-9 promoter region in order to perform haplotype analysis in combination with their data on MMP-9 (-1562C/T) polymorphism. These suggestions could provide additional information with clinical relevance to cancer susceptibility.

Y-STR diversity and ethnic admixture in White and Mulatto Brazilian population samples

We investigated 50 Mulatto and 120 White Brazilians for the Y-chromosome short tandem repeat (Y-STR) markers (DYS19, DYS390, DYS391, DYS392 and DYS393) and found 79 different haplotypes in the White and 35 in the Mulatto sample. Admixture estimates based on allele frequencies showed that the admixture of the white sample was 89 percent European, 6 percent African and 5 percent Amerindian while the Mulatto sample was 93 percent European and 7 percent African. Results were consistent with historical records of the directional mating between European males and Amerindian or African females.