Ana Fernández-Santander

Dr. Ana Fernández-Santander

Medicina, Universidad Europea, Madrid, Spain
orcid
Full professor of Genetics

Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 March 2020 in Journal of Oncology
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MGMaria Gaibar
Maria Gaibar
LBLaura Beltrán
Laura Beltrán
ARALICIA Romero-Lorca
ALICIA Romero-Lorca
Ana Fernández-SantanderAna Fernández-Santander
Ana Fernández-Santander
ANApolonia Novillo
Apolonia Novillo
In one of every four or five cases of breast cancer, the human epidermal growth factor receptor-2 (HER2) gene is overexpressed. These carcinomas are known as HER2-positive. HER2 overexpression is linked to an aggressive phenotype and a lower rate of disease-free and overall survival. Drugs such as trastuzumab, pertuzumab, lapatinib, neratinib, and the more recent afatinib target the deregulation of HER2 expression. Some authors have attributed somatic mutations in HER2, a role in resistance to anti-HER2 therapy as differential regulation of HER2 has been observed among patients. Recently, studies in metastatic ER + tumors suggest that some HER2 mutations emerge as a mechanism of acquired resistance to endocrine therapy. In an effort to identify possible biomarkers of the efficacy of anti-HER2 therapy, we here review the known single-nucleotide polymorphisms (SNPs) of the HER2 gene found in HER2-positive breast cancer patients and their relationship with clinical outcomes. Information was recompiled on 11 somatic HER2 SNPs. Seven polymorphisms are located in the tyrosine kinase domain region of the gene contrasting with the low number of mutations found in extracellular and transmembrane areas. HER2-positive patients carrying S310F, S310Y, R678Q, D769H, or I767M mutations seem good candidates for anti-HER2 therapy as they show favorable outcomes and a good response to current pharmacological treatments. Carrying the L755S or D769Y mutation could also confer benefits when receiving neratinib or afatinib. By contrast, patients with mutations L755S, V842I, K753I, or D769Y do not seem to benefit from trastuzumab. Resistance to lapatinib has been reported in patients with L755S, V842I, and K753I. These data suggest that exploring HER2 SNPs in each patient could help individualize anti-HER2 therapies. Advances in our understanding of the genetics of the HER2 gene and its relations with the efficacy of anti-HER2 treatments are needed to improve the outcomes of patients with this aggressive breast cancer.

30 June 2017 in Ethnicity & Health
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ARAntonio Ríos
Antonio Ríos
ALA. López-Navas
A. López-Navas
ALA. López-López
A. López-López
FGF.J. Gómez
F.J. Gómez
JIJ. Iriarte
J. Iriarte
PPP. Parrilla
P. Parrilla
Medical students represent a new generation of medical thought, and if they have a favourable attitude towards organ donation this will greatly encourage its promotion. To analyse the attitude of medical students in Spanish universities towards the donation of their own organs and to determine the factors affecting this attitude. Type of study: A sociological, interdisciplinary, multicentre, and observational study in Spain. Students studying a degree in medicine enrolled in Spain (n = 34,000). A sample of 9598 students (confidence of 99% and precision of ±1%), stratified by geographical area and academic year. Instrument of measurement: A validated questionnaire of attitude towards organ donation and transplantation (PCID-DTO RIOS) was self-administered and completed anonymously. The questionnaire completion rate was 95.7% (n = 9.275). 80% were in favour of donation, 2% against and 18% were undecided. The following main variables were related to a favourable attitude: being of the female sex (Odds Ratio = 1.739); being in the sixth year of the degree (OR = 2.506); knowing a donor (OR = 1.346); having spoken about the subject with one's family (OR = 2.132) and friends (OR = 1.333); having a family circle that is in favour, more specifically, having a father (OR = 1.841), mother (OR = 2.538) or partner in favour (OR = 2.192); being a blood donor (OR = 2.824); acceptance of the mutilation of the body if it were necessary (OR = 2.958); and being an atheist or an agnostic (OR = 1.766). Spanish medical students generally have a favourable attitude towards organ donation, although 20% are not in favour.

1 September 2011 in Health Technology Assessment
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NFN Fleeman
N Fleeman
CMCarlos Martin-Saborido
Carlos Martin-Saborido
KPKatherine Payne
Katherine Payne
ABA Boland
A Boland
RDR Dickson
R Dickson
TWT Walley
T Walley
Background Breast cancer is the uncontrolled, abnormal growth of malignant breast tissue affecting predominantly women. Metastatic breast cancer (mBC) is an advanced stage of the disease when the disease has spread beyond the original organ. Hormone receptor status and human epidermal growth factor 2 (HER2) status are two predictive factors that are taken into consideration when estimating the prognosis of patients with breast cancer. Objectives To review the clinical effectiveness and cost-effectiveness evidence base for lapatinib (LAP) in combination with an aromatase inhibitor (AI) and trastuzumab (TRA) in combination with an AI for the first-line treatment of patients who have hormone receptor-positive (HR+)/human epidermal growth factor 2-positive (HER2+) mBC. Data sources Relevant electronic databases and websites, including MEDLINE, EMBASE and the Cochrane Library, were searched until May 2010. Further data were derived from the manufacturers’ submissions for LAP + AI and TRA + AI. Review methods A systematic review of the clinical effectiveness and cost-effectiveness of LAP + AI and TRA + AI was undertaken. As it was deemed inappropriate to compare LAP + AI with TRA + AI, two separate assessments of cost-effectiveness versus AIs alone were undertaken. Results Three trials were included in the systematic review [the patient populations of the efficacy and safety of lapatinib combined with letrozole (EGF30008) trial, the efficacy and safety of trastuzumab combined with anastrozole (TAnDEM) trial and the efficacy and safety of letrozole combined with trastuzumab (eLEcTRA) trial]. As a result of differences in the exclusion criteria and because one trial was halted prematurely, comparisons across trials were believed to be inappropriate and meta-analysis was not possible. Individually, however, the findings from the trials all suggest that LAP + AI or TRA + AI results in improved progression-free survival and/or time to progression when compared with AIs alone. The trials do not show a statistically significant benefit in terms of overall survival. Two separate economic analyses were conducted based on the completed trials; neither LAP + AI nor TRA + AI was found to be cost-effective when compared with AI monotherapy. Limitations Because of differences in the EGF30008 and the TAnDEM trials, the Assessment Group believes the indirect comparisons analyses conducted by the manufacturers are inappropriate and, for the same reason, chooses not to compare LAP + AI with TRA + AI in an economic evaluation. Conclusions LAP + AI and TRA + AI appear to be clinically more effective than AI monotherapy, but neither is cost-effective compared with AIs alone. It was not possible to compare LAP + AI with TRA + AI. Future research should include research into treating mBC in the HR+/HER2+ population who are not TRA (or LAP) naive and into comparing the clinical effectiveness of AIs as monotherapy in patients with HER2+ and human epidermal growth factor 2-negative breast cancer. Funding The National Institute for Health Research Technology Assessment programme.

15 July 2015 in PLOS ONE
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ARAlicia Romero-Lorca
Alicia Romero-Lorca
ANApolonia Novillo
Apolonia Novillo
MGMaría Gaibar
María Gaibar
FMFERNANDO BANDRES MOYA
FERNANDO BANDRES MOYA
Ana Fernández-SantanderAna Fernández-Santander
Ana Fernández-Santander
Tamoxifen is used to prevent and treat estrogen-dependent breast cancer. It is described as a prodrug since most of its antiestrogen effects are exerted through its hydroxylated metabolites 4-OH-tamoxifen and endoxifen. In prior work, we correlated optimal plasma levels of these metabolites with certain genotypes of CYP2D6 and SULT1A2. This descriptive study examines correlations between concentrations of tamoxifen's glucuronide metabolites and genotypes UGT1A4 Pro24Thr, UGT1A4 Leu48Val, UGT2B7 His268Tyr, UGT2B15 Asp85YTyr UGT2B15 Lys523Thr and UGT2B17del in 132 patients with estrogen receptor-positive breast cancer under treatment with tamoxifen. Patients were genotyped by real-time and conventional PCR-RFLP. The glucuronides 4-OH-tamoxifen-N-glucuronide, 4-OH-tamoxifen-O-glucuronide and endoxifen-O-glucuronide were isolated from blood plasma and quantified using a high-pressure liquid chromatography-tandem mass spectrometry system. Individuals who were homozygous for UGT1A448VAL showed significantly lower mean concentrations of both glucuronide metabolites compared to subjects genotyped as wt/wt plus wt/48Val (p=0.037 and p=0.031, respectively). Women homozygous for UGT2B7268Tyr also showed mean substrate/product ratios of 4-OH-tamoxifen/4-OH-tamoxifen-O-glucuronide and 4-OH-tamoxifen/4-OH-tamoxifen-N-glucuronide indicative of reduced glucuronidase activity compared to wt homozygotes or to heterozygotes for the polymorphism (p=0.005 and p=0.003, respectively). In contrast, UGT2B15 Lys523Thr and UGT2B17del were associated with possibly increased enzyme activity. Patients with at least one variant allele UGT2B15523Thr showed significantly higher 4-OH-tamoxifen-O-glucuronide and endoxifen-glucuronide levels (p=0.023 and p=0.025, respectively) indicating a variant gene-dose effect. Higher 4-OH-tamoxifen-N-glucuronide levels observed in UGT2B17del genotypes (p=0.042) could be attributed to a mechanism that compensates for the greater expression of other genes in UGT2B17 del/del individuals. Our observations suggest that patients carrying mutations UGT1A448Val, UGT2B7268Tyr or with wt genotypes for UGT2B17nodel and UGT2B15523Lys could be the best candidates for a good response to tamoxifen therapy in terms of eliciting effective plasma active tamoxifen metabolite levels. However, additional studies examining the effects of UGT genotype on overall patient response to TAM are needed to further examine the role of UGT polymorphisms in the therapeutic efficacy of TAM.

29 July 2013 in PLOS ONE
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Ana Fernández-SantanderAna Fernández-Santander
Ana Fernández-Santander
MGMaría Gaibar
María Gaibar
ANApolonia Novillo
Apolonia Novillo
ARAlicia Romero-Lorca
Alicia Romero-Lorca
MRMargarita Rubio
Margarita Rubio
FMFERNANDO BANDRES MOYA
FERNANDO BANDRES MOYA
Tamoxifen is a pro-drug widely used in breast cancer patients to prevent tumor recurrence. Prior work has revealed a role of cytochrome and sulfotransferase enzymes in tamoxifen metabolism. In this descriptive study, correlations were examined between concentrations of tamoxifen metabolites and genotypes for CYP2D6, CYP3A4, CYP3A5, SULT1A1, SULT1A2 and SULT1E1 in 135 patients with estrogen receptor-positive breast cancer. Patients were genotyped using the Roche-AmpliChip® CYP450 Test, and Real-Time and conventional PCR-RFLP. Plasma tamoxifen, 4-hydroxy-tamoxifen, N-desmethyl-tamoxifen, endoxifen and tamoxifen-N-oxide were isolated and quantified using a high-pressure liquid chromatography-tandem mass spectrometry system. Significantly higher endoxifen levels were detected in patients with the wt/wt CYP2D6 compared to the v/v CYP2D6 genotype (p<0.001). No differences were detected in the remaining tamoxifen metabolites among CYP2D6 genotypes. Patients featuring the SULT1A2*2 and SULT1A2*3 alleles showed significantly higher plasma levels of 4-hydroxy-tamoxifen and endoxifen (p = 0.025 and p = 0.006, respectively), as likely substrates of the SULT1A2 enzyme. Our observations indicate that besides the CYP2D6 genotype leading to tamoxifen conversion to potent hydroxylated metabolites in a manner consistent with a gene-dose effect, SULT1A2 also seems to play a role in maintaining optimal levels of both 4-hydroxy-tamoxifen and endoxifen.

6 December 2009 in Annals of Human Biology
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MGMaria Gaibar
Maria Gaibar
EEEsther Esteban
Esther Esteban
PMPedro Moral
Pedro Moral
FGFélix Gómez-Gallego
Félix Gómez-Gallego
CSCatalina Santiago
Catalina Santiago
Ana Fernández-SantanderAna Fernández-Santander
Ana Fernández-Santander
Sixteen Y-chromosomal short tandem repeats (STRs) (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4.1) were typed in DNA samples from 52 unrelated men and 15 autosomal STRs (CSF1PO, D2S1338, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D19S433, D21S11, FGA, TH01, TPOX, vWA) were also studied for a group of 90 individuals (men and women) from the same population (Andalusians from La Alpujarra, South of Spain). The Alpujarrenian population represents an example of an isolated population with remarkable geographical, cultural and historical characteristics. High haplotype diversities were observed for the studied polymorphisms, 0.98 and 1 for YSTRs and autosomal STRs, respectively. Population comparisons for the autosomal STR allele distributions revealed remarkable levels of global homogeneity among samples geographically related.1.713 JCR (2010) Q2, 37/86 Biology, 63/142 Public, environmental & occupational healt