ABCB1 C3435T gene polymorphism as a potential biomarker of clinical outcomes in HER2-positive breast cancer patients.

HER2-positive breast cancer patients treated with trastuzumab schemes have good initial clinical outcomes. Despite this beneficial effect, many patients experiment resistance to these drugs. Several gene polymorphisms in ABCB1, HER2, and CCND1 have been proposed as potential predictors of clinical outcomes of trastuzumab schemes. The aim of this study was to evaluate the association between 4 gene polymorphisms potentially responsible for bad prognosis (HER2-Ile655Val, CCND1-A870G and ABCB1C1236T, C3435T) and clinical outcomes in HER2-positive BC patients. A retrospective cohorts study was performed. Eighty-four HER2-positive BC patients treated with trastuzumab schemes were included. The four gene polymorphisms were analyzed by PCR Real-Time with Taqman® probes. Genotypes were investigated for their association with tumor response, survival and resistance. Patients with CC genotype of ABCB1-C3435T presented higher risk of resistance to chemotherapy/trastuzumab schemes, compared to those carrying the T-allele (RR: 2.71; CI95%:1.29-5.68; p=0.013888), progression (RR: 1.89; p=0.017964); and exitus (RR: 2.09; p=0.03276). Multivariate logistic regression analysis considering clinical variables and ABCB1-C3435T revealed that the only independent factor associated to resistance to therapy was ABCB1-C3435T gene polymorphism (ORCT/CC: 0.25; p=0.0123; ORTT/CC: 0.09; p=0.0348. The protective effect of ABCB1-C3435T T-allele was confirmed in the multivariate Cox regression analysis for PFS (HRCT/CC: 0.41; p=0.00806; HRTT/CC: 0.22; p=0.01982) and OS (HRCT/CC: 0.49; p=0.0555; HRTT/CC: 0.12; p=0.0398). ABCB1-C1236T, CCND1-A870G and HER2-Ile655Val polymorphisms were not associated to resistance, PFS or OS (p>0.05). The A-allele for CCND1-rs9344 was associated with higher response rates (RR: 3.44; uncorrected p-value: 0.03816) in the bivariate analysis, but no statically association was found after Bonferroni correction (p=0.15264). ABCB1-C3435T, ABCB1-C1236T and HER2-Ile655Val gene polymorphisms were not associated with response. Although this study demonstrates a prognostic value of ABCB1-C3435T gene polymorphism to predict clinical outcomes, further studies with a larger sample will be necessary to validate this result.

Non-HER2 signaling pathways activated in resistance to anti-HER2 therapy in breast cancer.

HER2 receptor is overexpressed approximately in 20 % of human breast cancer (BC) and is a poor prognostic factor. Although therapies targeting this receptor have improved the prognosis of this cancer, up to 62 % patients treated with these drugs experiment progression during the first year of treatment. Some molecular mechanisms have been proposed to be responsible for this resistance, such as activation of alternative signaling pathways (through ERBB receptors and non-ERBB receptors or increased expression of ligands and alterations in HER2 signaling components). In this article, we will review the influence of genetic markers in non-HER2 signaling pathways investigated to date as cause of resistance to HER2-targeted drugs in HER2-positive BC patients. GRB7, included in the 17q12 amplicon, has been associated to poor prognosis in BC patients. Biomarkers like EPHAR and SRC, have demonstrated clinical relevance and prognostic value in HER2-positive BC patients. Non-invasive biomarkers, such as elevated IGF1 serum levels have been revealed as interesting biomarkers to be considered as predictors of trastuzumab clinical outcomes in BC patients. However, the prognostic value of most of the biomarkers investigated to date, such as HER3, IGF1R, PIK3CA, or AKT1 cannot be fully established yet, since results have not been conclusive.

Risk loci involved in giant cell arteritis susceptibility: a genome-wide association study.

BACKGROUND: Giant cell arteritis is an age-related vasculitis that mainly affects the aorta and its branches in individuals aged 50 years and older. Current options for diagnosis and treatment are scarce, highlighting the need to better understand its underlying pathogenesis. Genome-wide association studies (GWAS) have emerged as a powerful tool for unravelling the pathogenic mechanisms involved in complex diseases. We aimed to characterise the genetic basis of giant cell arteritis by performing the largest GWAS of this vasculitis to date and to assess the functional consequences and clinical implications of identified risk loci. METHODS: We collected and meta-analysed genomic data from patients with giant cell arteritis and healthy controls of European ancestry from ten cohorts across Europe and North America. Eligible patients required confirmation of giant cell arteritis diagnosis by positive temporal artery biopsy, positive temporal artery doppler ultrasonography, or imaging techniques confirming large-vessel vasculitis. We assessed the functional consequences of loci associated with giant cell arteritis using cell enrichment analysis, fine-mapping, and causal gene prioritisation. We also performed a drug repurposing analysis and developed a polygenic risk score to explore the clinical implications of our findings. FINDINGS: We included a total of 3498 patients with giant cell arteritis and 15 550 controls. We identified three novel loci associated with risk of giant cell arteritis. Two loci, MFGE8 (rs8029053; p=4·96 × 10-8; OR 1·19 [95% CI 1·12-1·26]) and VTN (rs704; p=2·75 × 10-9; OR 0·84 [0·79-0·89]), were related to angiogenesis pathways and the third locus, CCDC25 (rs11782624; p=1·28 × 10-8; OR 1·18 [1·12-1·25]), was related to neutrophil extracellular traps (NETs). We also found an association between this vasculitis and HLA region and PLG. Variants associated with giant cell arteritis seemed to fulfil a specific regulatory role in crucial immune cell types. Furthermore, we identified several drugs that could represent promising candidates for treatment of this disease. The polygenic risk score model was able to identify individuals at increased risk of developing giant cell arteritis (90th percentile OR 2·87 [95% CI 2·15-3·82]; p=1·73 × 10-13). INTERPRETATION: We have found several additional loci associated with giant cell arteritis, highlighting the crucial role of angiogenesis in disease susceptibility. Our study represents a step forward in the translation of genomic findings to clinical practice in giant cell arteritis, proposing new treatments and a method to measure genetic predisposition to this vasculitis. FUNDING: Institute of Health Carlos III, Spanish Ministry of Science and Innovation, UK Medical Research Council, and National Institute for Health and Care Research.

Impact of nutritional and educational support on home enteral nutrition.

BACKGROUND: Home Enteral Nutrition (HEN) is used to prevent or correct malnutrition in outpatients. Due to the complexity of this process, the indication, follow-up, and results of an educational program of HEN patients was evaluated. METHODS: A prospective, observational, real-life, multicenter study was performed in 21 Spanish Hospital. Patients receiving HEN by nasogastric tube or ostomy were included. The following variables were collected: age, gender, HEN indication, type of formula, nutritional requirements, laboratory variables, complications, and quality standards of the educational program. To calculate the energy and protein requirements, the FAO/WHO/UNU formula was used considering the adjusted weight of the patients. All data were analyzed using SPSS.24. RESULTS: 414 patients were included. Most conditions diagnosed were neurodegenerative diseases (64.8%). 100 (25.3%) were diabetic. The mean weight was 59.3 ± 10.4 kg and BMI 22.6 ± 3.2. Moderate protein-calorie malnutrition was predominant at baseline (46.4%). Improvement in nutritional status at six months was recorded in more than 75% of patients (p < 0.05). Tolerance problems, diarrhea and abdominal distension fell between the 3- and 6-month visits (p < 0.05). Patients who received intermittent EN had fewer tolerance-related effects (OR 0.042; 95% CI 0.006-0.279) and less diarrhoea (OR 0.042; 95% CI 0.006-0.279). At the baseline and 6-month visits, compliance with the educational measures proposed by the prescriber was ≥ 99%. CONCLUSION: The nutritional assessment to prescribe individualized HEN to each patient, together with educational measures and training in the proper use of this treatment for both patients and trainers, improves nutritional status and reduces the onset of adverse events.

-Omic Approaches and Treatment Response in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is an inflammatory disorder characterized by an aberrant activation of innate and adaptive immune cells. There are different drugs used for the management of RA, including disease-modifying antirheumatic drugs (DMARDs). However, a significant percentage of RA patients do not initially respond to DMARDs. This interindividual variation in drug response is caused by a combination of environmental, genetic and epigenetic factors. In this sense, recent -omic studies have evidenced different molecular signatures involved in this lack of response. The aim of this review is to provide an updated overview of the potential role of -omic approaches, specifically genomics, epigenomics, transcriptomics, and proteomics, to identify molecular biomarkers to predict the clinical efficacy of therapies currently used in this disorder. Despite the great effort carried out in recent years, to date, there are still no validated biomarkers of response to the drugs currently used in RA. -Omic studies have evidenced significant differences in the molecular profiles associated with treatment response for the different drugs used in RA as well as for different cell types. Therefore, global and cell type-specific -omic studies analyzing response to the complete therapeutical arsenal used in RA, including less studied therapies, such as sarilumab and JAK inhibitors, are greatly needed.

Association of ABCB1 and VEGFA gene polymorphisms with breast cancer susceptibility and prognosis.

Breast cancer (BC) is the most common cause of cancer-related death in women worldwide. Several ABCB1 and VEGFA gene polymorphisms, such as ABCB1-G1199 T/A (rs2229109), VEGFA -634 G > C (rs2010963), VEGFA 2578 C > A (rs699947) and VEGFA 7 C > T (rs25648) have been associated with risk of BC and clinical outcomes. The purpose of this study was to evaluate the association between these gene polymorphisms and BC risk and prognosis. A retrospective case-control study was conducted, including 84 BC cases and 119 controls of Spanish (European, Caucasian) origin. ABCB1-G1199 T/A (rs2229109), VEGFA -634 G > C (rs2010963), VEGFA 2578 C > A (rs699947) and VEGFA 7 C > T (rs25648) gene polymorphisms were analysed by TaqMan®. The genotypic logistic regression model adjusted by aged revealed no association with any of the polymorphisms and BC risk, although the C-allele of VEGFA 2578 C > A showed a trend to higher BC risk in the allelic and recessive models (p = 0.055 and 0.054, respectively). There was no influence of these gene polymorphisms on overall survival (OS). The univariate Cox model showed that carriers of the A-allele for VEGFA 2578 C > A tended to have longer OS compared to CC patients (CC vs A-allele Hazard ratio (HR): 2.08; CI95 % = 0.96-4.49; p = 0.0587). There was no association between the gene polymorphisms analysed and disease-free survival (DFS). The univariate Cox model showed a trend toward a longer DFS in patients carrying ABCB1-G1199 T/A GG genotype compared to those with A-allele (GG vs A-allele HR: 0.43; CI95 % = 0.18-1.03; p = 0.0612). No influence of ABCB1-G1199 T/A (rs2229109), VEGFA -634 G > C (rs2010963), VEGFA 2578 C > A (rs699947) and VEGFA 7 C > T (rs25648) gene polymorphisms on risk of developing BC was found in our study. There was no association between the polymorphisms studied and DFS and OS.

ABCB1 gene polymorphisms and response to chemotherapy in breast cancer patients: A meta-analysis.

The ABCB1 gene encodes the P-glycoprotein, an efflux pump for some antineoplastic agents which acts as a resistance mechanism to chemotherapy. Three SNPs (C3435T, C1236T and G2677T/A), are the most widely studied in ABCB1. The inconsistent conclusions about the association of these polymorphisms and the response to chemotherapy in breast cancer (BC) patients prompted us to conduct a meta-analysis. A total of nine (770 patients), five (566 patients) and three studies (367 patients) relating the ABCB1 C3435T, C1236T and G2677T/A polymorphisms respectively, were included. The main analysis revealed a lack of association between ABCB1 polymorphisms and response to chemotherapy in every genetic model: C3435T (dominant OR: 0.888; 95%CI: 0.558-1.413), C1236T (dominant OR: 1.968; 95%CI: 0.609-6.362) and G2677T/A (GG vs GT + GA + TT + TA + AA OR: 0.854; 95%CI: 0.418-1.744). Stratification by ethnicity, cancer type and response criteria did not change the pattern of results. The available evidence indicates that three polymorphisms within ABCB1; C3435T, C1236T and G2677T/A, cannot be considered a reliable predictor of response to chemotherapy in BC patients.

De novo resistance biomarkers to anti-HER2 therapies in HER2-positive breast cancer.

Therapies targeting HER2 receptor, overexpressed in 20% breast cancer (BC), improved prognosis, however ~62% patients experiment progression during the first year. Molecular mechanisms proposed to be responsible for this de novo resistance include HER2 modifications, defects in the antibody dependent cellular cytotoxicity or in cell arrest and apoptosis or alterations in HER2 signaling components. This article will review the influence of genetic markers investigated to date as cause of de novo resistance to HER2-targeted drugs in HER2-positive BC patients. Biomarkers like p95HER2, CCND1 and CDC25A have demonstrated clinical relevance and prognostic value in HER2-positive BC patients. However, the prognostic value of most biomarkers investigated to date, such as PIK3CA or AKT1, cannot be fully established yet.