Search

Background: Metastatic breast cancer is the second leading cause of death among women globally. A better understanding of tumor biology, and the availability of high-throughput technologies, have enabled the emergence of precision medicine bringing new expectations and giving rise to molecular screening programs (MSP). SOLTI, as a collaborative Spanish network, designed AGATA, the first multi-institutional MSP ever implemented in this country. Here, we report both the primary and some of the secondary results of the pilot study. Methods: A total of 10 sites within SOLTI network in Spain participated. DNA-sequencing of 56 cancer related genes was performed using FFPE tumor samples (primary or metastatic). Each clinical case was reviewed by a multidisciplinary advisory board (MAB), which recommended, in a prospective manner, potential experimental treatments, mainly in the context of clinical trials. The primary objective was to determine the success rate of matching a DNA alteration to an experimental drug or drug class. Secondary objectives included a comprehensive molecular characterization of tumor samples by PAM50 subtyping and quantification of protein expression levels by MASS-SPEC (70 proteins panel). Results: 305 patients (pts) were screened from September 2014 to July 2017 and 260 (85.3%) were finally evaluated by the MAB. Pts characteristics were: mean age 54 years (29-80), ER+/HER2- (n=192; 74%), HER2+ (n=30; 11.5%) and TNBC (n=38; 14.5%). 163 primary tumors and 97 metastatic samples were profiled. Regarding the primary objective, 116 pts (45%) presented at least one mutation (range 1-6) that could be matched to a drug or drug class. Of these, 13 pts (11.2%) received therapy matched to their molecular profile according to the MAB recommendation and their follow-up is still on-going. No mutation was detected in 97 (37%) pts (WT), and 47 patients (18.1%) presented a mutation but no match was possible. The most common mutations were PIK3CA (34%), TP53 (22%), AKT1 (5%), ESR1 (3%) and ERBB2 (3%). Intrinsic subtype distribution in 177 samples was as follows: 34% Luminal A (n=60); 21% Luminal B (n=36); 13% HER2E (n=22); 19% Basal-like (n=34) and 13% Normal-like (n=23). Compared to primary tumors (n=110), the proportion of HER2-enriched disease in metastatic tumors (n=63) was significantly higher (6% vs 20%; p=0.005). Protein expression analysis was performed in 146 samples (94 primary and 57 metastasis). In 19 cases (13%), the outlier expression of some targetable proteins (FGFR1 [n=4, 2.7%], IGF1R [n=4, 2.7%], EGFR [n=1, 0.7%], CEACAM5 [n=6, 4.1%], IDO1 [n=2, 1.37%], TROP2 [n=2, 1.37%]) were identified. Of note, HER2 overexpression (>740 amol/μg) was observed in 4 HER2- cases. Finally, among WT tumors, 21% presented a potential drug-matched protein target. Conclusions: Nationwide molecular screening in Spain is feasible. Nearly half of patients had tumors with mutation(s), mostly PIK3CA, that could be matched to a potential drug or drug class. PAM50 profile might be helpful to navigate towards a therapeutic decision making, although the MAB could not make any targeted-driven recommendation yet with this data. More clinical evidence is needed to use MASS-SPEC as a diagnostic tool. Citation Format: Pernas S, Villagrasa P, Nuciforo PG, Vivancos A, Scaltriti M, Rodón J, Burgués O, Canes J, Dueñas M, Cecchi F, Vidal M, Lluch A, Perelló A, Llombart A, Dorca J, Montaño A, Oliveira M, Ribas G, Rapado I, Paré L, Prat A, Ciruelos E. Primary and secondary results of the first nationwide molecular screening program in Spain for patients with advanced breast cancer (AGATA SOLTI-1301 study) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-02.

The METTEN study assessed the efficacy, tolerability, and safety of adding metformin to neoadjuvant chemotherapy plus trastuzumab in early HER2-positive breast cancer (BC). Women with primary, non-metastatic HER2-positive BC were randomized (1:1) to receive metformin (850 mg twice-daily) for 24 weeks concurrently with 12 cycles of weekly paclitaxel plus trastuzumab, followed by four cycles of 3-weekly FE75C plus trastuzumab (arm A), or equivalent regimen without metformin (arm B), followed by surgery. Primary endpoint was the rate of pathological complete response (pCR) in the per-protocol efficacy population. pCR rate was numerically higher in the metformin-containing arm A (19 of 29 patients [65.5%, 95% CI: 47.3–80.1]) than in arm B (17 of 29 patients [58.6%, 95% CI: 40.7–74.5]; OR 1.34 [95% CI: 0.46–3.89], P = 0.589). The rate of breast-conserving surgery was 79.3% and 58.6% in arm A and B (P = 0.089), respectively. Blood metformin concentrations (6.2 μmol/L, 95% CI: 3.6–8.8) were within the therapeutic range. Seventy-six percent of patients completed the metformin-containing regimen; 13% of patients in arm A dropped out because of metformin-related gastrointestinal symptoms. The most common adverse events (AEs) of grade ≥3 were neutropenia in both arms and diarrhea in arm A. None of the serious AEs was deemed to be metformin-related. Addition of anti-diabetic doses of metformin to a complex neoadjuvant regimen was well tolerated and safe. Because the study was underpowered relative to its primary endpoint, the efficacy data should be interpreted with caution.

Background: Epidemiological, pre-clinical, and window-of-opportunity trials have suggested that the anti-diabetic drug metformin (MET) may have beneficial effects on breast cancer (BC). The clinical relevance of combining MET with current standards of care for first-line treatment of BC is unknown. We investigated the safety and efficacy of adding MET to neoadjuvant chemotherapy plus trastuzumab (TTZ) in patients with HER2-positive early BC. Methods: In a randomized, multicenter, open-label phase 2 study, women with operable, locally advanced, or inflammatory HER2+ BC were randomly assigned in a 1:1 ratio to receive daily MET (1,700 mg) for 24 weeks concurrently with 12 cycles of weekly paclitaxel plus TTZ followed by four cycles of fluorouracil, epirubicin, cyclophosphamide/3w plus TTZ (arm A) or equivalent sequential chemotherapy plus TTZ without MET (arm B), followed by surgery. Patients were stratified by age, extent of disease (cT2 cN0-1 vs ≥ T3 or ≥ N2), and hormone receptor (HR)-status. The intention-to-treat (ITT) safety population comprised all women who underwent randomization and received at least one treatment dose. Primary endpoint was the rate of pathological complete response (pCR) analyzed in the per-protocol (PP) efficacy population. pCR was defined as absence of invasive cancer in the breast and axillary nodes, irrespective of carcinoma in situ (ypT0/is ypN0). Results: From June 1, 2012 to March 17, 2016, 98 patients were assessed for eligibility at 10 centers in Spain. Of 84 (85.7%) patients who were randomized, 41 patients were allocated to arm A and 43 to arm B. The most common adverse effects (AEs) in the 79 ITT patients were fatigue, diarrhea, nausea, alopecia, sensory neuropathy, mucositis, neutropenia, and elevated AST/ALT. Most AEs were grades 1–2 (>90% in both arms). The most common AEs grade ≥3 were neutropenia (7/38 women in arm A and 5/41 women in arm B) and diarrhea (5 and 0, respectively). The number of serious AEs was 3 in arm A (none of them was deemed to be MET-related) and 2 in arm B. At week 12, one (2.9%) patient in arm A and 6 (15%) in arm B exhibited asymptomatic decreases in the left ventricular ejection fraction (LVEF). At week 24, none (0%) of the patients in arm A and 3 (7.9%) patients in arm B presented decreases of LVEF below 50% and >10% from baseline. Only one patient (2.7%) in arm B experienced symptomatic heart failure. The rates of breast-conserving surgery were 79.3% and 58.6% in PP arms A and B, respectively. Also, 19/29 PP patients in arm A (65.5%, 95% CI 47–80) had a pCR versus 17/29 PP patients (58.6%, 95% CI 41–74) in arm B (OR 1.34 [95% CI 0.46–3.89], p=0.589). The combined rates of pCR and near-pCR (ypT1aN0) were 79.3% in arm A and 72.4% in arm B. Significantly fewer pCR were noted for tumors that were HR-positive regardless of which arm the patients were randomized. Conclusion: The higher pCR rate in HER2+ BC patients receiving MET-containing neoadjuvant therapy and TTZ did not reach statistical significance. Evaluation of long-term outcome data such as 5-year disease-free survival and correlative biological studies are needed to evaluate the clinico-molecular relevance of these findings. Citation Format: Pernas S, Dorca J, Álvarez-López I, Martínez S, Saura C, Batista López N, Rodríguez-Sánchez CA, Amillano K, Domínguez-Fernández S, Luque Cabal M, Morilla I, Viñas G, Cortés J, Cuyàs E, Verdura S, Fernández-Arroyo S, Joven J, Pérez E, García M, Bosch N, López-Bonet E, Saidani S, Buxó M, Menendez JA, Martin-Castillo B. Safety and efficacy of neoadjuvant metformin with trastuzumab and chemotherapy in women with HER2-positive early breast cancer: A randomized, open-label, multicenter, phase 2 trial [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-10-01.

In animal models of breast cancer, resistance to continuous use of letrozole can be reversed by withdrawal and reintroduction of letrozole. We therefore hypothesised that extended intermittent use of adjuvant letrozole would improve breast cancer outcome compared with continuous use of letrozole in postmenopausal women.We did the multicentre, open-label, randomised, parallel, phase 3 SOLE trial in 240 centres (academic, primary, secondary, and tertiary care centres) in 22 countries. We enrolled postmenopausal women of any age with hormone receptor-positive, lymph node-positive, and operable breast cancer for which they had undergone local treatment (surgery with or without radiotherapy) and had completed 4-6 years of adjuvant endocrine therapy. They had to be clinically free of breast cancer at enrolment and without evidence of recurrent disease at any time before randomisation. We randomly assigned women (1:1) to treatment groups of either continuous use of letrozole (2·5 mg/day orally for 5 years) or intermittent use of letrozole (2·5 mg/day orally for 9 months followed by a 3-month break in years 1-4 and then 2·5 mg/day during all 12 months of year 5). Randomisation was done by principal investigators or designee at respective centres through the internet-based system of the International Breast Cancer Study Group, was stratified by type of previous endocrine therapy (aromatase inhibitors only vs selective oestrogen receptor modulators only vs both therapies), and used permuted block sizes of four and institutional balancing. No one was masked to treatment assignment. The primary endpoint was disease-free survival, analysed by the intention-to-treat principle using a stratified log-rank test. All patients in the intention-to-treat population who initiated protocol treatment during their period of trial participation were included in the safety analyses. This study is registered with ClinicalTrials.gov, number NCT00553410, and EudraCT, number 2007-001370-88; and long-term follow-up of patients is ongoing.Between Dec 5, 2007, and Oct 8, 2012, 4884 women were enrolled and randomised after exclusion of patients at a non-adherent centre, found to have inadequate documentation of informed consent, immediately withdrew consent, or randomly assigned to intervention groups in error. 4851 women comprised the intention-to-treat population that compared extended intermittent letrozole use (n=2425) with continuous letrozole use (n=2426). After a median follow-up of 60 months (IQR 53-72), disease-free survival was 85·8% (95% CI 84·2-87·2) in the intermittent letrozole group compared with 87·5% (86·0-88·8) in the continuous letrozole group (hazard ratio 1·08, 95% CI 0·93-1·26; p=0·31). Adverse events were reported as expected and were similar between the two groups. The most common grade 3-5 adverse events were hypertension (584 [24%] of 2417 in the intermittent letrozole group vs 517 [21%] of 2411 in the continuous letrozole group) and arthralgia (136 [6%] vs 151 [6%]). 54 patients (24 [1%] in the intermittent letrozole group and 30 [1%] in the continuous letrozole group) had grade 3-5 CNS cerebrovascular ischaemia, 16 (nine [1%] vs seven [1%]) had grade 3-5 CNS haemorrhage, and 40 (19 [1%] vs 21 [1%]) had grade 3-5 cardiac ischaemia. In total, 23 (1%) of 4851 patients died while on trial treatment (13 [1%] of 2417 patients in the intermittent letrozole group vs ten [1%] of 2411 in the continuous letrozole group).In postmenopausal women with hormone receptor-positive breast cancer, extended use of intermittent letrozole did not improve disease-free survival compared with continuous use of letrozole. An alternative schedule of extended adjuvant endocrine therapy with letrozole, including intermittent administration, might be feasible and the results of the SOLE trial support the safety of temporary treatment breaks in selected patients who might require them.Novartis and the International Breast Cancer Study Group.

Homocisteïna; Càncer de mama; Dieta cetogènica Homocisteína; Cáncer de mama; Dieta cetogénica Homocysteine; Breast cancer; Ketogenic diet Certain dietary interventions might improve the therapeutic index of cancer treatments. An alternative to the “drug plus diet” approach is the pharmacological reproduction of the metabolic traits of such diets. Here we explored the impact of adding metformin to an established therapeutic regimen on the systemic host metabolism of cancer patients. A panel of 11 serum metabolites including markers of mitochondrial function and intermediates/products of folate-dependent one-carbon metabolism were measured in paired baseline and post-treatment sera obtained from HER2-positive breast cancer patients randomized to receive either metformin combined with neoadjuvant chemotherapy and trastuzumab or an equivalent regimen without metformin. Metabolite profiles revealed a significant increase of the ketone body β-hydroxybutyrate and of the TCA intermediate α-ketoglutarate in the metformin-containing arm. A significant relationship was found between the follow-up levels of homocysteine and the ability of treatment arms to achieve a pathological complete response (pCR). In the metformin-containing arm, patients with significant elevations of homocysteine tended to have a higher probability of pCR. The addition of metformin to an established anti-cancer therapeutic regimen causes a fasting-mimicking modification of systemic host metabolism. Circulating homocysteine could be explored as a clinical pharmacodynamic biomarker linking the antifolate-like activity of metformin and biological tumor response. This work was supported by grants from the Ministerio de Sanidad, Servicios Sociales e Igualdad (EC10-125, Ayudas para el Fomento de la Investigación Clínica Independiente to Begoña Martin-Castillo). Work in the Menendez laboratory is supported by the Ministerio de Ciencia e Innovación (Grant SAF2016-80639-P, Plan Nacional de l+D+I, founded by the European Regional Development Fund [EU FEDER], Spain) and by an unrestricted research grant from the Fundació Oncolliga Girona (Lliga catalana d’ajuda al malalt de càncer, Girona).

Background Benefit derived from adjuvant chemotherapy (CT) is doubtful in a high percentage of patients (pt) with hormone-receptor–positive HER2 negative early breast cancer. The 21-gene recurrence-score (RS) assay Oncotype DX, provide prognostic and predictive information. Results of the TAYLORx study have confirmed that most of patients with negative node status and RS > 25 can avoid CT without increasing their risk of relapse. However, pt 20 showed benefit with CT. Methods Aim: To analyse the impact of age using RS test to change the indication of adjuvant CT and the relationship between different clinical pathological factors and the RS value. We analysed 240 cases out of 251 RS test performed in the 3 ICO Centers during 2017-2018. We compared the adjuvant treatment initially planned according to institutional protocol with the treatment given after RS in the total cohort and in pt Results CT was indicated in all pt before knowing the RS results. Only 46 pt (19%) received CT after RS results. 14 out of 88 pt 25 ( 25 in a multivariate analysis. Table . 209P Age median (range) 53 (19-76) Tumor size median 15 mm Histological grade G1 23% G2 69.7% G3 4.4% Progesterone receptor ≤20% 21% >20% 78% Ki67 median (p25-75) 20 (13,28) ≤14 27% 14-25 41% >25% 31% Nodal status pN0 57% pN1mic 15% pN1a 27% Conclusions 82% of pt of our series could avoid CT, however this proportion change after TAYLORx results in younger patients. Today 75% of these pt would had avoided CT. Ki67 > 25% and Progesterone Receptor ≤20% were the only pathological factors associated with an increased risk of RS > 25. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

Background: The minor allele (C) of the single-nucleotide polymorphism (SNP) rs11212617, located near the ataxia telangiectasia mutated (ATM) gene, has been associated with an increased likelihood of treatment success with metformin in type 2 diabetes. We herein investigated whether the same SNP would predict clinical response to neoadjuvant metformin in women with early breast cancer (BC). Methods: DNA was collected from 79 patients included in the intention-to-treat population of the METTEN study, a phase 2 clinical trial of HER2-positive BC patients randomized to receive either metformin combined with anthracycline/taxane-based chemotherapy and trastuzumab or equivalent regimen without metformin, before surgery. SNP rs11212617 genotyping was assessed using allelic discrimination by quantitative polymerase chain reaction. Results: Logistic regression analyses revealed a significant relationship between the rs11212617 genotype and the ability of treatment arms to achieve a pathological complete response (pCR) in patients (odds ratio [OR]genotype×arm = 10.33, 95% confidence interval [CI]: 1.29–82.89, p = 0.028). In the metformin-containing arm, patients bearing the rs11212617 C allele had a significantly higher probability of pCR (ORA/C,C/C = 7.94, 95%CI: 1.60–39.42, p = 0.011). Conversely, no association was found between rs11212617 and clinical response in the reference arm (ORA/C,C/C = 0.77, 95%CI: 0.20–2.92, p = 0.700). After controlling for tumor size and hormone receptor status, the rs11212617 C allele remained a significant predictor of pCR solely in the metformin-containing arm. Conclusions: If reproducible, the rs11212617 C allele might warrant consideration as a predictive clinical biomarker to inform the personalized use of metformin in BC patients. Trial Registration: EU Clinical Trials Register, EudraCT number 2011-000490-30. Registered 28 February 2011, https://www.clinicaltrialsregister.eu/ctr-search/trial/2011-000490-30/ES.

Metformina; Ki67; Càncer de mama Metformina; Ki67; Cáncer de mama Metformin; Ki67; Breast cancer The proliferative capacity of residual breast cancer (BC) disease indicates the existence of partial treatment resistance and higher probability of tumor recurrence. We explored the therapeutic potential of adding neoadjuvant metformin as an innovative strategy to decrease the proliferative potential of residual BC cells in patients failing to achieve pathological complete response (pCR) after pre-operative therapy. We performed a prospective analysis involving the intention-to-treat population of the (Metformin and Trastuzumab in Neoadjuvancy) METTEN study, a randomized multicenter phase II trial of women with primary, non-metastatic (human epidermal growth factor receptor 2) HER2-positive BC evaluating the efficacy, tolerability, and safety of oral metformin (850 mg twice-daily) for 24 weeks combined with anthracycline/taxane-based chemotherapy and trastuzumab (arm A) or equivalent regimen without metformin (arm B), before surgery. We centrally evaluated the proliferation marker Ki67 on sequential core biopsies using visual assessment (VA) and an (Food and Drug Administration) FDA-cleared automated digital image analysis (ADIA) algorithm. ADIA-based pre-operative values of high Ki67 (≥20%), but not those from VA, significantly predicted the occurrence of pCR in both arms irrespective of the hormone receptor status (p = 0.024 and 0.120, respectively). Changes in Ki67 in residual tumors of non-pCR patients were significantly higher in the metformin-containing arm (p = 0.025), with half of all patients exhibiting high Ki67 at baseline moving into the low-Ki67 (

Clinically HER2+ (cHER2+) breast cancer (BC) can no longer be considered a single BC disease entity in terms of trastuzumab responsiveness. Here we propose a framework for predicting the response of cHER2+ to trastuzumab that integrates the molecular distinctions of intrinsic BC subtypes with recent knowledge on cancer stem cell (CSC) biology. First, we consider that two interchangeable populations of epithelial-like, aldehyde dehydrogenase (ALDH)-expressing and mesenchymal-like, CD44+CD24-/low CSCs can be found in significantly different proportions across all intrinsic BC subtypes. Second, we overlap all the intrinsic subtypes across cHER2+ BC to obtain a continuum of mixed phenotypes in which one extreme exhibits a high identity with ALDH+ CSCs and the other extreme exhibits a high preponderance of CD44+CD24-/low CSCs. The differential enrichment of trastuzumab-responsive ALDH+ CSCs versus trastuzumab-refractory CD44+CD24-/low CSCs can explain both the clinical behavior and the primary efficacy of trastuzumab in each molecular subtype of cHER2+ (i.e., HER2-enriched/cHER2+, luminal A/cHER2+, luminal B/cHER2+, basal/cHER2+, and claudin-low/cHER2+). The intrinsic plasticity determining the epigenetic ability of cHER2+ tumors to switch between epithelial and mesenchymal CSC states will vary across the continuum of mixed phenotypes, thus dictating their intratumoral heterogeneity and, hence, their evolutionary response to trastuzumab. Because CD44+CD24-/low mesenchymal-like CSCs distinctively possess a highly endocytic activity, the otherwise irrelevant HER2 can open the door to a type of "Trojan horse" approach by employing antibody-drug conjugates such as T-DM1, which will allow a rapid and CSC-targeted delivery of cytotoxic drugs to therapeutically manage trastuzumab-unresponsive basal/cHER2+ BC. Contrary to the current dichotomous model used clinically, our model proposes that a reclassification of cHER2+ tumors based on the spectrum of molecular BC subtypes might inform on their CSC-determined sensitivity to trastuzumab, thus providing a better delineation of the predictive value of cHER2+ in BC by incorporating CSCs-driven intra-tumor heterogeneity into clinical decisions.

Background: Cancer cells require nutrients to survive in the unfavorable microenvironment of primary solid tumors or metastases before angiogenesis development. Fatty acid synthase (FASN) is a multi-enzyme protein that catalyzes fatty acid synthesis. Expression levels of FASN are low or undetectable in normal human tissues except for the liver and the adipose tissue. In contrast, high levels of FASN expression have been detected in breast cancer tumors and other human carcinomas. Several reports highlight that FASN overexpression in tumor samples correlates with progression, aggressiveness and metastatic potential of the disease. In adition, some studies have suggested the same correlation with serum levels of FASN. Our aim was to analyze the association between the expression of tumor and serum levels of FASN with clinical and pathological prognostic factors in early-stage breast cancer patients. Methods: Fifty-five patients with early-stage breast cancer treated with surgery and post-operative chemotherapy were included in the study. We prospectively measured the levels of FASN in tumor and serum samples. Clinical data included demographic characteristics, menarche, pregnancy, breast feeding, menopausal status and body mass index (BMI). Pathological and molecular data included: pathological state, histological grade, estrogen and progesterone receptors, HER2 status, p53 mutation and Ki 67 levels. FASN tissue expression levels were determined by IHC and circulating FASN levels were determined by ELISA. FASN expression was graded from 0 to 3+, meaning 0–1+ normal amounts of FASN protein compared to non-tumor breast tissue, 2+ moderate amounts and 3+ the highest levels of FASN expression. Baseline characteristics were summarized descriptively. Categorical variables were compared by c2 or Fisher's exact. For continuous variables, if the data are approximately normal, the two groups were compared using ANOVA. If the normality assumption is not warranted, then the Kruskall-Wallis test has been used. Results: Median age was 49 (rage 33–77). 51% of the patients were menopausal and median BMI was 24,75. Thirty-four percent of the patients had stage I, 51% stage II and 15% stage III. We observed a statistically significant association between FASN over expression and the lack of progesterone receptors (p = 0.027) in tumor samples. In contrast, we found no relation between FASN and estrogen receptor nor between FASN and HER2 tumor expression in this setting. Menopause and age were strongly related to higher levels of FASN tumor expression (p < 0.001). Patients with higher BMI had higher levels of FASN in tumor tissue although this association was not statistically significant (p = 0.07). Finally, we observed a positive relation between breast cancer stage and the levels of FASN tumor (p = 0.05). In contrast, circulating FASN levels were not associated with any pathological or clinical prognostic factor. Conclusions: Our study suggests that FASN overexpression is significantly related to age, menopausal status, more advanced stages and lack of progesterone receptor expression in early-stage breast cancer patients. However, no relation between serum levels of FASN and the clinical or molecular prognostic factors have been observed. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-09-10.

Silvia Cufi 1,2 , Bruna Corominas-Faja 1,2 , Alejandro Vazquez-Martin 1,2 , Cristina Oliveras-Ferraros 1,2 , Joan Dorca 2,3 , Joaquim Bosch-Barrera 2,3 , Begona Martin-Castillo 2,4 , Javier A. Menendez 1,2 1 Translational Research Laboratory, Catalan Institute of Oncology (ICO), Girona, Spain 2 Girona Biomedical Research Institute (IDIBGi), Girona, Spain 3 Medical Oncology, Catalan Institute of Oncology (ICO), Girona, Spain 4 Clinical Research Unit, Catalan Institute of Oncology (ICO), Girona, Spain Received: April 27, 2012, Accepted: April 28, 2012, Published: May 4, 2012, Keywords: Metformin, trastuzumab, HER2, cancer stem cells, breast cancer Correspondence: Javier A. Menendez, email: // // Abstract Trastuzumab-refractory breast cancer stem cells (CSCs) could also explain the high rate of primary resistance to single-agent trastuzumab in HER2 gene-amplified breast cancer patients. The identification of agents with strong selective toxicity for trastuzumab-resistant breast CSCs may have tremendous relevance for how HER2+ breast cancer patients should be treated. Using the human breast cancer cell line JIMT-1, which was established from the pleural metastasis of a patient who was clinically resistant to trastuzumab ab initio , we examined whether preferential killing of the putative CD44 + CD24 -/low breast CSC population might be sufficient to overcome primary resistance to trastuzumab in vivo . Because recent studies have shown that the anti-diabetic biguanide metformin can exert antitumor effects by targeted killing of CSC-like cells, we explored whether metformin’s ability to preferentially kill breast cancer initiating CD44 + CD24 -/low cells may have the potential to sensitize JIMT-1 xenograft mouse models to trastuzumab. Upon isolation for breast cancer initiating CD44 + CD24 -/low cells by employing magnetic activated cell sorting, we observed the kinetics of metformin-induced killing drastically varied among CSC and non-CSC subpopulations. Metformin’s cell killing effect increased dramatically by more than 10-fold in CD44 + CD24 -/low breast CSC cells compared to non-CD44 + CD24 -/low immunophenotypes. While seven-weeks treatment length with trastuzumab likewise failed to reduce tumor growth of JIMT-1 xenografts, systemic treatment with metformin as single agent resulted in a significant two-fold reduction in tumor volume. When trastuzumab was combined with concurrent metformin, tumor volume decreased sharply by more than four-fold. Given that metformin-induced preferential killing of breast cancer initiating CD44 + CD24 -/low subpopulations is sufficient to overcome in vivo primary resistance to trastuzumab, the incorporation of metformin into trastuzumab-based regimens may provide a valuable strategy for treatment of HER2+ breast cancer patients.

Background: HER2-negative metastatic breast cancer (MBC) patients with central nervous system (CNS) involvement previously treated with a local therapy had very few possibilities of disease response with conventional systemic treatments. Liposomal irinotecan (nal-IRI) is a novel formulation of irinotecan. It has shown promising activity in patients with CNS involvement. The aim of this trial is to evaluate the efficacy of nal-IRI as single agent in HER2-negative MBC patients with CNS progression following local treatment with surgery, stereotactic radiosurgery or whole-brain radiotherapy. Trial design: This is an open label, non-randomized, multicenter two-stage phase IIA clinical trial. Patients will receive intravenous nal-IRI in a fixed dose of 60 mg/m2 expressed as irinotecan hydrochloride trihydrate salt on day 1 of a 14-day cycle until progression or unacceptable toxicity. The principal selection criteria are: (1) HER2-negative inoperable MBC with CNS involvement; (2) prior local treatment with surgery, stereotactic radiosurgery or whole-brain radiotherapy; (3) prior treatment with taxanes; (4) at least one measurable brain lesion according to RECIST v1.1 criteria. The primary objective is to evaluate the efficacy of naI-IRI monotherapy. Primary endpoint is the CNS overall response rate (ORR), defined as the percentage of patients who experienced complete (CR) and partial response (PR) (as best response). It will be assessed in accordance with the Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria. The trial uses a Simon's minimax two-stage design. We hypothesized that excluding a CNS ORR ≤5% while targeting an improvement of the CNS ORR to ≥15% would be an optimal approach for evaluating the study strategy. At least 2 responders among 23 patients will be necessary to proceed to the second stage. At the study end, ≥6 responders out of 56 evaluable subjects are required to justify this strategy in further clinical trials. Considering a drop-out rate of 10%, a sample size of 63 patients will be needed to attain 80% power at nominal level of one-sided alpha of 0.05. The secondary objectives include safety-related outcomes and efficacy measures: CNS clinical benefit rate (CR, PR and stable disease [SD] ≥12 weeks), ORR according to a CNS volumetric parameter (CR, PR and >65% reduction of CNS lesion), clinical benefit rate (CR, PR and SD ≥24 weeks), progression-free survival and overall survival. Trial registration: NCT03328884. Date of registration: November 1st, 2017. First patient included: July, 05th 2017. Citation Format: Javier Cortés, David Paez, José Manuel Pérez García, Salvador Blanch Tormo, Kepa Amillano Parraga, Manuel Ruiz Borrego, Antonio Antón Torres, María Fernández, Emilio Alba Conejo, Miguel Ángel Seguí Palmer, Joan Dorca Ribugent, Rafael López López, Mireia Margelí Vila, Elena Aguirre, Antonio Llombart. Multicenter open-label, phase II trial, to evaluate the efficacy and safety of liposomal irinotecan (nal-IRI) for progressing brain metastases in patients with HER2-negative breast cancer (The Phenomenal Study) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT154.

// Begona Martin-Castillo 1, 2 , Eugeni Lopez-Bonet 2, 3 , Maria Buxo 2, 4, 5 , Joan Dorca 6 , Francesc Tuca-Rodriguez 7 , Miguel Alonso Ruano 7 , Ramon Colomer 8, 9 , Javier A. Menendez 2, 10 1 Unit of Clinical Research, Catalan Institute of Oncology, Girona, Catalonia, Spain 2 Girona Biomedical Research Institute (IDIBGI), Molecular Oncology Group, Girona, Catalonia, Spain 3 Department of Anatomical Pathology, Dr. Josep Trueta Hospital of Girona, Girona, Catalonia, Spain 4 Epidemiology Unit and Cancer Registry of Girona (UERCG), Catalan Cancer Plan, Catalan Health Government, Girona, Catalonia, Spain 5 Department of Nursing, Universitat de Girona (UdG), Girona, Catalonia, Spain 6 Medical Oncology Department, Catalan Institute of Oncology, Girona, Catalonia, Spain 7 Department of Gynecology, Dr. Josep Trueta Hospital of Girona, Girona, Catalonia, Spain 8 Breast Cancer Clinical Research Unit, CNIO-Spanish National Cancer Research Center, Madrid, Spain 9 Medical Oncology Department, Hospital La Princesa, Madrid, Spain 10 Translational Research Laboratory, Catalan Institute of Oncology (ICO), Girona, Catalonia, Spain Correspondence to: Javier A. Menendez, e-mail: jmenendez@iconcologia.net , jmenendez@idibgi.org Keywords: Breast cancer, HER2, basal-like, trastuzumab, cytokeratins Received: December 22, 2014 Accepted: January 08, 2015 Published: January 29, 2015 ABSTRACT There is an urgent need to refine the prognostic taxonomy of HER2+ breast carcinomas and develop easy-to-use, clinic-based prediction algorithms to distinguish between good- and poor- responders to trastuzumab-based therapy. Building on earlier studies suggesting that HER2+ tumors enriched with molecular and morpho-immunohistochemical features classically ascribed to basal-like tumors are highly aggressive and refractory to trastuzumab, we investigated the prognostic and predictive value of the basal-HER2+ phenotype in HER2-overexpressing tumors. Our retrospective cohort study of a consecutive series of 152 HER2+ primary invasive ductal breast carcinomas first confirmed the existence of a distinct subgroup co-expressing HER2 protein and basal cytokeratin markers CK5/6, the so-called basal-HER2+ phenotype. Basal-HER2+ phenotype (≥10% of cells showing positive CK5/6 staining), but not estrogen receptor status, was significantly associated with inferior overall survival by univariate analysis and predicted worsened disease free survival after accounting for strong prognostic variables such as tumor size at diagnosis in stepwise multivariate analysis. In the sub-cohort of HER2+ patients treated with trastuzumab-based adjuvant/neoadjuvant therapy, basal-HER2+ phenotype was found to be the sole independent prognostic marker for a significantly inferior time to treatment failure in multivariate analysis. A CK5/6-based immunohistochemical fingerprint may provide a simple, rapid, and accurate method for re-classifying women diagnosed with HER2+ breast cancer in a manner that can improve prognosis and therapeutic planning in patients with clinically aggressive basal-HER2+ tumors who are not likely to benefit from trastuzumab-based therapy.

OBJECTIVE Overexpression of fatty acid synthase (FASN), the enzyme involved in the de novo synthesis of fatty acids, has been reported in several human carcinomas, including breast cancer, and has been related to poor prognosis. Our aim was to analyze the association of FASN tumor tissue expression with clinicopathological and anthropometrical features in early-stage breast cancer patients. METHODS We prospectively studied 53 women with early-stage breast cancer who were treated with surgical operation and postoperative chemotherapy. RESULTS Menopause status and age were strongly associated with higher levels of FASN tumor expression (P < 0.005 and P = 0.038, respectively). Body mass index and pathological stage were also related to FASN tumor expression. CONCLUSIONS Our findings suggest that FASN could be a potential therapeutic target in postmenopausal breast cancer patients. However, further studies are needed.

Purpose Adding taxanes to anthracycline-based adjuvant therapy improves survival outcomes of patients with node-positive breast cancer (BC). Currently, however, most patients with BC are node negative at diagnosis. The only pure node-negative study (Spanish Breast Cancer Research Group 9805) reported so far showed a docetaxel benefit but significant toxicity. Here we tested the efficacy and safety of weekly paclitaxel (wP) in node-negative patients, which is yet to be established. Patients and Methods Patients with BC having T1-T3/N0 tumors and at least one high-risk factor for recurrence (according to St. Gallen 1998 criteria) were eligible. After primary surgery, 1,925 patients were randomly assigned to receive fluorouracil, doxorubicin, and cyclophosphamide (FAC) × 6 or FAC × 4 followed by wP × 8 (FAC-wP). The primary end point was disease-free survival (DFS) after a median follow-up of 5 years. Secondary end points included toxicity and overall survival. Results After a median follow-up of 63.3 months, 93% and 90.3% of patients receiving FAC-wP or FAC regimens, respectively, remained disease free (hazard ratio [HR], 0.73; 95% CI, 0.54 to 0.99; log-rank P = .04). Thirty-one patients receiving FAC-wP versus 40 patients receiving FAC died (one and seven from cardiovascular diseases, respectively; HR, 0.79; 95% CI, 0.49 to 1.26; log-rank P = .31). The most relevant grade 3 and 4 adverse events in the FAC-wP versus the FAC arm were febrile neutropenia (2.7% v 3.6%), fatigue (7.9% v 3.4%), and sensory neuropathy (5.5% v 0%). Conclusion For patients with high-risk node-negative BC, the adjuvant FAC-wP regimen was associated with a small but significant improvement in DFS compared with FAC therapy, in addition to manageable toxicity, especially regarding long-term cardiac effects.

A total of 18 patients with locally advanced (Stage III) adenocarcinoma and large cell undifferentiated carcinoma of the lung, previously untreated, were enrolled in a Phase II trial. Treatment consisted of carboplatin 325 mg/m 2 , day 1 and etoposide 100 mg/m 2 on days 2 and 3. All patients were evaluable for response. Of these, one patient had a partial response (5.5%; confidence interval 0–24%). Toxicity comprised mainly leukopenia and anaemia. Other toxicities were mild. This Phase II study evidenced a poor response rate for these regimes on adenocarcinoma and large cell undifferentiated carcinoma of the lung.

1048 Background: Oral chemotherapy (CT) is an attractive treatment option for hormone receptor positive, metastatic breast cancer (MBC) patients (pts) pretreated by a hormone therapy. In our phase II study, we evaluated the role of single-agent Oral Vinorelbine (OV) as first-line CT in pts presenting bone metastases without visceral involvement. In this abstract, first safety results of this trial are presented. Methods: Main eligibility criteria included: age ≥18 years, documented bone involvement previously untreated by CT, hormone receptor positive disease previously treated by at least one hormone therapy, HER2-negative disease, Karnofsky PS ≥70 and absence of visceral metastases. Study treatment (until progression): OV 80 mg/m2 weekly (following a first cycle at 60 mg/m2 and dose escalation to 80 in the absence of grade 3 or 4 toxicity). One cycle was defined as four weeks of treatment. Results: Main pts characteristics in the full population were (n=70): median age: 60.6 years (34% ≥65 years); media...

1001 Background: Adjuvant weekly paclitaxel (wP) sequential to anthracyclines improves the outcome of operable node-positive BC patients (pts) [Sparano NEJM 2008, Martin BCRT 2009]; however, most BC pts are currently node-negative at diagnosis. The role of wP in these pts is not well established yet. Methods: Pts aged 18-70, with T1-T3/N0 operable BC and at least one high-risk St Gallen 1998 criteria (size >2 cm, hormone-receptor [HR] negative, grade 2/3, age 2 every 3w) or FAC x4→wP x8 (paclitaxel 100 mg/m2 weekly). The primary endpoint was DFS. The trial was designed to detect an absolute 5-y DFS increase of 5% (80% FAC, 85% FAC→wP); a sample size of 1812 evaluable patients (906 per arm) was required to detect this difference (α=0.05, β= 80%). Assuming a drop-out rate of 6%, 1929 pts were required. The first analysis of DFS was planned when a median follow-up of 5 years was reached. Results: Between September 2003 and October 2008, 1925 pts (FAC 974, FAC→wP 951) were randomized. Patient characteristics were well balanced between arms, median age was 50, 73% of pts were HR positive and 9% HER2 positive. 97% of pts with FAC and 85% of pts with FAC→wP completed all treatment as planned. The median dose intensity was 98% with FACx6, 99% with FACx4 and 98% with wP. The most frequent grade 3-4 toxicities (>3% in either arm) with FAC vs FAC→wP were neutropenia (25% vs 22%) with 4% vs 3% of febrile neutropenia, fatigue (3% vs 8%), sensory neuropathy (0 vs 5%), and vomiting (4% in each arm). After a median follow-up of 5.3 years, the proportion of patients disease free is 93% and 90% with FAC→wP and FAC (HR for relapse 0.732, 95% CI: 0.542 to 0.990; log-rank p-value=0.0423). Conclusions: For pts with high-risk node-negative BC, adjuvant FAC→wP was associated with a small but significant improvement in DFS compared with FAC, with manageable toxicity.

Cancer cells expressing constitutively active phosphatidylinositol-3 kinase (PI3K) are proliferative regardless of the absence of insulin, and they form dietary restriction (DR)-resistant tumors in vivo. Because the binding of insulin to its receptors activates the PI3K/AKT/mammalian target of rapamycin (mTOR) signaling cascade, activating mutations in the PIK3CA oncogene may determine tumor response to DR-like pharmacological strategies targeting the insulin and mTOR pathways. The anti-diabetic drug metformin is a stereotypical DR mimetic that exerts its anti-cancer activity through a dual mechanism involving insulin-related (systemic) and mTOR-related (cell-autonomous) effects. However, it remains unclear whether PIK3CA-activating mutations might preclude the anti-cancer activity of metformin in vivo. To model the oncogenic PIK3CA-driven early stages of cancer, we used the clonal breast cancer cell line MCF10DCIS.com, which harbors the gain-of-function H1047R hot-spot mutation in the catalytic domain of the PI3KCA gene and has been shown to form DR-refractory xenotumors. To model PIK3CA-activating mutations in late stages of cancer, we took advantage of the isogenic conversion of a PIK3CA-wild-type tumor into a PIK3CA H1047R-mutated tumor using the highly metastatic colorectal cancer cell line SW48. MCF10DCIS.com xenotumors, although only modestly affected by treatment with oral metformin (approximately 40% tumor growth inhibition), were highly sensitive to the intraperitoneal (i.p.) administration of metformin, the anti-cancer activity of which increased in a time-dependent manner and reached >80% tumor growth inhibition by the end of the treatment. Metformin treatment via the i.p. route significantly reduced the proliferation factor mitotic activity index (MAI) and decreased tumor cellularity in MCF10DCIS.com cancer tissues. Whereas SW48-wild-type (PIK3CA+/+) cells rapidly formed metformin-refractory xenotumors in mice, ad libitum access to water containing metformin significantly reduced the growth of SW48-mutated (PIK3CAH1047R/+) xenotumors by approximately 50%. Thus, metformin can no longer be considered as a bona fide DR mimetic, at least in terms of anti-cancer activity, because tumors harboring the insulin-unresponsive, DR-resistant, PIK3CA-activating mutation H1047R remain sensitive to the anti-tumoral effects of the drug. Given the high prevalence of PIK3CA mutations in human carcinomas and the emerging role of PIK3CA mutation status in the treatment selection process, these findings might have a significant impact on the design of future trials evaluating the potential of combining metformin with targeted therapy.