Vascular endothelial growth factor polymorphisms and clinical outcome in patients with metastatic breast cancer treated with weekly docetaxel

Single nucleotide polymorphisms as the efficient prognostic markers in breast cancer

BACKGROUND

Breast cancer (BC) is known as the most common malignancy in women. Environmental and genetic factors are associated with BC progression. Genetic polymorphisms have been reported as important risk factors of BC prognosis and drug response. Main body: Therefore, in the present review, we have summarized all single nucleotide polymorphisms (SNPs) which have been significantly associated with drug response in BC patients around the world. We have also categorized the reported SNPs based on their related genes functions to clarify the molecular biology of drug responses in BC.

CONCLUSION

The majority of SNPs were reported in detoxifying enzymes, which introduced such genes as the main genetic risk factors during BC drug responses. This review paves the way for introducing a prognostic panel of SNPs for the BC patients in the world.

Genetic Variation in the Vascular Endothelial Growth Factor (VEGFA) Gene at rs13207351 Is Associated with Overall Survival of Patients with Head and Neck Cancer

Simple Summary

Angiogenesis and apoptosis play a pivotal role in the pathogenesis and clinical course not only of nasopharyngeal cancer (NPC), but also of other subgroups of head and neck cancer (HNC), such as laryngeal cancer. Thus, the aim of this study was to investigate the clinical significance of genetic polymorphisms in four pivotal angiogenesis- and apoptosis-related genes (VEGFA, FAS, EDNRA and NBS1) in HNC patients. Thirty-four genetic variants located in the studied genes were assessed. Two of them (VEGFA rs13207351 and FAS rs2234768) were associated with overall survival for patients with laryngeal cancer and NPC, respectively, with VEGFA rs13207351 showing the most promise for its prognostic value in the subgroup of laryngeal cancer patients. This study suggests that genetic variations in angiogenesis- and apoptosis-related genes may be useful in the management of HNC patients.

Abstract

Head and neck cancer (HNC) is a significantly heterogeneous disease and includes malignancies arising from different anatomical sites, such as nasopharyngeal cancer (NPC) and laryngeal cancer (LC). In the current study, polymorphisms located in angiogenesis- and apoptosis-related genes (VEGFA, FAS, EDNRA and NBS1) were evaluated regarding their clinical significance in HNC patients. In total, 333 HNC patients were enrolled in this study and 34 variants located on the aforementioned genes were genotyped via Sanger sequencing. LC patients, homozygous A for VEGFA rs13207351, had shorter overall survival (OS) as opposed to homozygous G (Hazard ratio (HR) = 2.06, Wald’s p = 0.017) upon adjustment for age, disease stage, and surgery. Following the dominant model, LC patients carrying the A allele had a marginally significantly higher risk for death (HR = 1.72, p = 0.059). NPC patients heterozygous (CT) for FAS rs2234768 had a marginal but significantly higher risk of death compared to those with homozygosity for the T allele (HR = 2.22, p = 0.056). In conclusion, rs13207351 (VEGFA) and rs2234768 (FAS) polymorphisms seem to have prognostic significance in HNC, with VEGFA rs13207351 showing the most promise in this subgroup of LC patients.

Pharmacogenetic-Based Interactions between Nutraceuticals and Angiogenesis Inhibitors

Background: Angiogenesis inhibitors (AIs) have become established as an effective cancer treatment. Whereas their interactions with antineoplastic drugs have extensively been investigated, little is known of the effect of their co-administration with nutraceuticals/dietary supplements (N/DSs), which are often self-prescribed. N/DSs comprise a wide range of products such as herbs, nutrients, vitamins, minerals, and probiotics. Assessment of their interactions with cancer drugs, particularly AIs, is hampered by the difficulty of gauging the amount of active substances patients actually take. Moreover, there is no agreement on which approach should be used to determine which N/DSs are most likely to influence AI treatment efficacy. We present a comprehensive review of the metabolic routes of the major AIs and their possible interactions with N/DSs. Methods: The PubMed and Cochrane databases were searched for papers describing the metabolic routes of the main AIs and N/DSs. Results: Data from the 133 studies thus identified were used to compile a diagnostic table reporting known and expected AI-N/DS interactions based on their metabolization pathways. AIs and N/DSs sharing the cytochrome P450 pathway are at risk of negative interactions. Conclusions: Recent advances in pharmacogenetics offer exceptional opportunities to identify prognostic and predictive markers to enhance the efficacy of individualized AI treatments. The table provides a guide to genotyping patients who are due to receive AIs and is a promising tool to prevent occult AI-N/DS interactions in poor metabolizers. N/DS use by cancer patients receiving AIs is a topical problem requiring urgent attention from the scientific community.

Prognostic evaluation of VEGFA genotypes and haplotypes in a cohort of Brazilian women with non metastatic breast cancer

Vascular Endothelial Growth Factor (VEGF) mediates angiogenesis, which is crucial for tumor development and progression. The present study aimed to evaluate the impact of VEGFA gene polymorphisms rs699947, rs833061, rs1570360, rs2010963 and rs3025039 on breast cancer features and prognosis. A cohort of Brazilian women (N = 1038) with unilateral non-metastatic breast cancer was evaluated. The association between VEGFA polymorphisms and histopathological features or pathological complete response (pCR) to neoadjuvant chemotherapy was evaluated by the Chi-square test, with calculation of the respective odds ratio (OR) and 95% confidence intervals (95% CI). The impact of individual categories on disease-free survival was evaluated using Kaplan-Meier curves and multivariate Cox proportional hazards regression models for calculation of adjusted hazard ratios (HRadjusted). Variant genotypes of rs699947 (CA + AA) were significantly associated with high-grade (G2 + G3) tumors (OR = 1.82; 95% CI = 1.15 - 2.89), and with shorter disease-free survival among patients treated with neoadjuvant chemotherapy followed by mastectomy (HRadjusted = 1.82; 95% CI = 1.16 - 2.86). Variant genotypes of rs833061 (TC + CC) were significantly associated with high-grade (G2 + G3) tumors (OR = 1.79; 95% CI = 1.12 - 2.84) and with positive lymph node status (OR = 1.34; 95% CI = 1.01 - 1.77), but showed no independent effect on disease-free survival. Variant haplotypes (*2 to *5) appear to favor pCR (OR = 7.1; 95% CI = 1.7 - 30.1). VEGFA genotyping may add to prognostic evaluation of breast cancer, with rs699947 being the most likely to contribute.

Prognostic and predictive role of vascular endothelial growth factor polymorphisms in breast cancer

Current evidence indicates that angiogenesis plays an important role in the pathogenesis of several malignancies, including breast cancer. The vascular endothelial growth factor (VEGF) pathway has been investigated extensively, due to its important role in angiogenesis. The major mediator of tumor angiogenesis is VEGF-A, frequently referred to as VEGF, which activates the VEGF receptor-2. The VEGF gene is located on chromosome 6 and constitutes a highly polymorphic gene. Numerous SNPs in the promoter, 5′- and 3′-untranslated regions (UTR) of VEGF gene have been recognized. This genetic variability possibly influences the production and function of VEGF. Subsequently, the VEGF SNPs may have an impact on breast cancer risk and disease outcome. Moreover, these SNPs may be of predictive value in patients receiving agents targeting the VEGF pathway. This review presents an update on the potential role of VEGF SNPs as prognostic and/or predictive markers in patients with breast cancer.