HER2 mutation as an emerging target in advanced breast cancer.

HER2 activating mutations have emerged as oncogenic drivers and therapeutic targets in a variety of human tumors. In breast cancer, these deregulations occur at low frequency, and are mostly detected in HER2-nonamplified, metastatic disease. Preclinical evidence has clarified the role of hotspot mutations in HER2 constitutive activation, defining them as an alternative mechanism to HER2 gene amplification. Furthermore, recent clinical studies have indicated the emergence of newly acquired HER2 deregulations in significant proportions of breast cancer patients who experience disease progression following both endocrine and HER2-targeted therapies. As the involvement of HER2 mutation in therapy resistance may profoundly impact patient outcomes on successive therapies, several clinical trials are currently investigating the efficacy of various HER2-targeted drugs in HER2-mutant breast cancer. In this review, we firstly summarize the structural organization of the HER2 oncogene and its historical impact on breast cancer prognosis and therapeutic advancement. Then, we provide an overview of the frequencies and functional relevance of clinically recurrent HER2 mutations in breast cancer with a special focus on their role in therapeutic resistance. Finally, we provide a collection of the clinical trials that are currently exploring novel therapeutic approaches for this patient subset and discuss the related perspectives and challenges.

ID4-dependent secretion of VEGFA enhances the invasion capability of breast cancer cells and activates YAP/TAZ via integrin ß3-VEGFR2 interaction.

Understanding the mechanisms of breast cancer cell communication underlying cell spreading and metastasis formation is fundamental for developing new therapies. ID4 is a proto-oncogene overexpressed in the basal-like subtype of triple-negative breast cancer (TNBC), where it promotes angiogenesis, cancer stem cells, and BRACA1 misfunction. Here, we show that ID4 expression in BC cells correlates with the activation of motility pathways and promotes the production of VEGFA, which stimulates the interaction of VEGFR2 and integrin ß3 in a paracrine fashion. This interaction induces the downstream focal adhesion pathway favoring migration, invasion, and stress fiber formation. Furthermore, ID4/ VEGFA/ VEGFR2/ integrin ß3 signaling stimulates the nuclear translocation and activation of the Hippo pathway member's YAP and TAZ, two critical executors for cancer initiation and progression. Our study provides new insights into the oncogenic roles of ID4 in tumor cell migration and YAP/TAZ pathway activation, suggesting VEGFA/ VEGFR2/ integrin ß3 axis as a potential target for BC treatment.

PD-L1 testing in metastatic triple negative breast cancer: Results of an Italian survey.

BACKGROUND: Immunotherapy has revolutionized the approach to metastatic triple-negative breast cancers. Atezolizumab was approved for patients with metastatic triple-negative breast cancers whose tumors express PD-L1, determined by SP 142 assay. To assess the availability and practice of SP142 test we administered a survey to all the 15 pathology departments of the Lazio Region during a six-month period. METHODS: The survey comprised 12 questions regarding the availability of SP142 in the pathology departments, the percentage of positive tests, the difficulties of pathologists in cases close to cut-off value and the tested samples. RESULTS: The SP142 assay was available in only eight centers. In case of positive result, most centers (5/8, 62.5%) reported values of PD-L1 expression ranging from > 1 to ⩽ 5%, with values close to the cut-off point (⩾ 1% or < 1%) being the greatest challenge.Most of the centers (6/8, 75%) tested material from both their own and other hospitals. In most centers, the evaluations were performed either on primary tumors or metastasis, in particular lymph nodes (5/8, 62.5%), followed by lung (3/8, 37.5%) and liver (1/8, 12.5%) metastasis. CONCLUSION: Our results raise some important issues concerning the evaluation of PD-L1 in the "real-life" setting, providing strategies for its implementation.

Advancing the PD-L1 CPS test in metastatic TNBC: Insights from pathologists and findings from a nationwide survey.

Pembrolizumab has received approval as a first-line treatment for unresectable/metastatic triple-negative breast cancer (mTNBC) with a PD-L1 combined positive score (CPS) of ≥ 10. However, assessing CPS in mTNBC poses challenges. Firstly, it represents a novel analysis for breast pathologists. Secondly, the heterogeneity of PD-L1 expression in mTNBC further complicates the assessment. Lastly, the lack of standardized assays and staining platforms adds to the complexity. In KEYNOTE trials, PD-L1 expression was evaluated using the IHC 22C3 pharmDx kit as a companion diagnostic test. However, both the 22C3 pharmDx and VENTANA PD-L1 (SP263) assays are validated for CPS assessment. Consequently, assay-platform choice, staining conditions, and scoring methods can significantly impact the testing outcomes. This consensus paper aims to discuss the intricacies of PD-L1 CPS testing in mTNBC and provide practical recommendations for pathologists. Additionally, we present findings from a nationwide Italian survey elucidating the state-of-the-art in PD-L1 CPS testing in mTNBC.

Clinical-radiomic models based on digital breast tomosynthesis images: a preliminary investigation of a predictive tool for cancer diagnosis.

Objective: This study aimed to develop a clinical-radiomic model based on radiomic features extracted from digital breast tomosynthesis (DBT) images and clinical factors that may help to discriminate between benign and malignant breast lesions. Materials and methods: A total of 150 patients were included in this study. DBT images acquired in the setting of a screening protocol were used. Lesions were delineated by two expert radiologists. Malignity was always confirmed by histopathological data. The data were randomly divided into training and validation set with an 80:20 ratio. A total of 58 radiomic features were extracted from each lesion using the LIFEx Software. Three different key methods of feature selection were implemented in Python: (1) K best (KB), (2) sequential (S), and (3) Random Forrest (RF). A model was therefore produced for each subset of seven variables using a machine-learning algorithm, which exploits the RF classification based on the Gini index. Results: All three clinical-radiomic models show significant differences (p < 0.05) between malignant and benign tumors. The area under the curve (AUC) values of the models obtained with three different feature selection methods were 0.72 [0.64,0.80], 0.72 [0.64,0.80] and 0.74 [0.66,0.82] for KB, SFS, and RF, respectively. Conclusion: The clinical-radiomic models developed by using radiomic features from DBT images showed a good discriminating power and hence may help radiologists in breast cancer tumor diagnoses already at the first screening.

Breast cancer metastasis: Is it a matter of OMICS and proper ex-vivo models?

Genomics has greatly increased the understanding of the study of breast cancer (BC) and has shaped the concept of intra-tumor heterogeneity, currently recognized as a propelling force for cancer progression. In this context, knowledge and understanding of metastatic breast cancer (mBC) has somehow lagged behind that of primary breast cancer. This may be explained by the relative scarcity of matched mBC samples, however it is possible that the mutation spectrum obtained from primary BC does not capture the full complexity of the metastatic disease. Here, we provide a few examples supporting this possibility, from public databases. We evoke the need to perform an integrated multi-OMICS characterization of mBC, to obtain a broad understanding of this complex disease, whose evolution cannot be explained solely by genomics. Pertinent to this, we suggest that rather an infrequent use of Patient-Derived -Tumor-Organoids (PDTOs) may be influenced by assuming that the metastatic conditions of PDTOs growth (mPDTOs) should be similar to those of the tissue of origin. We challenge this view by suggesting that the use of "target-organ inspired" growth conditions for mPDTOs, may better fit the emerging knowledge of metastatic disease. Thus, the integrated use of multi-OMICS and of clinically relevant mPDTOs may allow a further understanding of such disease and foster therapeutically relevant advances. We believe that our points may be valid for other solid cancers.

MALAT1-dependent hsa_circ_0076611 regulates translation rate in triple-negative breast cancer.

Vascular Endothelial Growth Factor A (VEGFA) is the most commonly expressed angiogenic growth factor in solid tumors and is generated as multiple isoforms through alternative mRNA splicing. Here, we show that lncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) and ID4 (inhibitor of DNA-binding 4) protein, previously referred to as regulators of linear isoforms of VEGFA, induce back-splicing of VEGFA exon 7, producing circular RNA circ_0076611. Circ_0076611 is detectable in triple-negative breast cancer (TNBC) cells and tissues, in exosomes released from TNBC cells and in the serum of breast cancer patients. Circ_0076611 interacts with a variety of proliferation-related transcripts, included MYC and VEGFA mRNAs, and increases cell proliferation and migration of TNBC cells. Mechanistically, circ_0076611 favors the expression of its target mRNAs by facilitating their interaction with components of the translation initiation machinery. These results add further complexity to the multiple VEGFA isoforms expressed in cancer cells and highlight the relevance of post-transcriptional regulation of VEGFA expression in TNBC cells.

Reverse strategy to locally advanced breast implant-associated anaplastic large cell lymphoma: A case report.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare T-cell lymphoma associated with textured breast implants. The most common presentation is a periprosthetic seroma that occurs at least 1 year after an aesthetic or reconstructive implantation, and in these cases, the surgical treatment seems to be successful. More rarely, BIA-ALCL presents with locally advanced mass-formed disease and a related regional lymph node involvement. In all these cases with worse prognosis, a multidisciplinary approach is required, including adjuvant chemotherapy, radiation therapy, and surgery. We present a clinical case of a 49-year-old woman who developed on the left side of the breast a mass-formed stage 3 BIA-ALCL 15 years after a bilateral breast augmentation with textured silicone implant. Our multidisciplinary team (MDT) scheduled the patient for a "reverse-strategy" sequential approach consisting of induction chemotherapy, hematopoietic stem cell mobilization, and harvest followed by autologous stem cell transplant (ASCT). After 100 days from the stem cell transplant, the patient showed a complete pathologic response and was a candidate for radical surgery. She underwent removal of both implants with total en bloc capsulectomy. On the left site, the periprosthetic mass was also en bloc removed. We did not perform any axillary dissection. Our surgical and hemato-oncological teams followed the patient every 3 months, and no local or systemic recurrences were observed 24 months after surgery. This case report has demonstrated the effectiveness of neoadjuvant chemotherapy as part of a "reverse strategy" in selected cases of advanced-stage BIA-ALCL in which it was not possible to perform an immediate radical surgery. Furthermore, in our case, the de-escalation strategy adopted permitted a less demolitic surgery with good functional and aesthetic results.

The prognostic relevance of HER2-positivity gain in metastatic breast cancer in the ChangeHER trial.

In metastatic breast cancer (mBC), the change of human epidermal growth factor receptor 2 (HER2) status between primary and metastatic lesions is widely recognized, however clinical implications are unknown. Our study address the question if relevant differences exist between subjects who preserve the HER2 status and those who gain the HER2 positivity when relapsed. Data of patients affected by HER2-positive mBC, treated with pertuzumab and/or trastuzumab-emtansine (T-DM1) in a real-world setting at 45 Italian cancer centers were retrospectively collected and analyzed. From 2003 to 2017, 491 HER2-positive mBC patients were included. Of these, 102 (20.7%) had been initially diagnosed as HER2-negative early BC. Estrogen and/or progesterone receptor were more expressed in patients with HER2-discordance compared to patients with HER2-concordant status (p < 0.0001 and p = 0.006, respectively). HER2-discordant tumors were characterized also by a lower rate of brain metastases (p = 0.01) and a longer disease free interval (p < 0.0001). Median overall survival was longer, although not statistically significant, in the subgroup of patients with HER2-discordant cancer with respect to patients with HER2-concordant status (140 vs 78 months, p = 0.07). Our findings suggest that patients with HER2-positive mBC with discordant HER2 status in early BC may have different clinical, biological and prognostic behavior compared to HER2-concordant patients.

p53 and BLC2 Immunohistochemical Expression Across Molecular Subtypes in 1099 Early Breast Cancer Patients With Long-Term Follow-up: An Observational Study.

INTRODUCTION: p53 and antiapoptotic B-cell leukemia/lymphoma 2 (BLC2) have been proposed as prognostic markers for early breast cancer (BC), although their relationship with conventional parameters and patient prognosis, as well as their distribution within the molecular BC subtypes remains uncertain. PATIENTS AND METHODS: In this observational study, we analyzed the immunohistochemical expression of p53 and BLC2 in 1099 early BC patients surgically treated between 2000 and 2006 and followed for at least 5 years, also considering their association with pathologic factors and molecular subtypes, as well as their influence on disease-free survival. RESULTS: p53 and BLC2 are distributed differently across molecular subtypes (P < .0001); in particular, p53 positivity and BLC2 negativity seems to be associated with more aggressive conventional tumor phenotypes. Moreover, BLC2 negativity seems to be a significant discriminating factor for disease-free survival (P = .003) according to Kaplan-Meier analysis, while p53 seems to have no discriminating effect. Among patients with discordant p53/BLC2 phenotype, the combination p53+BLC2- seems to be associated with the worst outcomes (P = .007) and significantly influenced the clinical course of node-negative patients treated only with hormone therapy (P = .004). CONCLUSION: These two biomarkers, in addition to conventional pathologic factors and molecular subtype, could help define the risk and outcome of BC.

Observational Multicenter Study on the Prognostic Relevance of Coagulation Activation in Risk Assessment and Stratification in Locally Advanced Breast Cancer. Outline of the ARIAS Trial.

A hypercoagulable state may either underlie or frankly accompany cancer disease at its onset or emerge in course of cancer development. Whichever the case, hypercoagulation may severely limit administration of cancer therapies, impose integrative supporting treatments and finally have an impact on prognosis. Within a flourishing research pipeline, a recent study of stage I-IIA breast cancer patients has allowed the development of a prognostic model including biomarkers of coagulation activation, which efficiently stratified prognosis of patients in the study cohort. We are now validating our risk assessment tool in an independent cohort of 108 patients with locally advanced breast cancer with indication to neo-adjuvant therapy followed by breast surgery. Within this study population, we will use our tool for risk assessment and stratification in reference to 1. pathologic complete response rate at definitive surgery, intended as our primary endpoint, and 2. rate of thromboembolic events, intended as our secondary endpoint. Patients' screening and enrollment procedures are currently in place. The trial will be shortly enriched by experimental tasks centered on next-generation sequencing techniques for identifying additional molecular targets of treatments which may integrate current standards of therapy in high-risk patients.

PLC-gamma-1 phosphorylation status is prognostic of metastatic risk in patients with early-stage Luminal-A and -B breast cancer subtypes.

BACKGROUND: Phospholipase Cγ1 (PLCγ1) is highly expressed in human tumours. Our previous studies reported that both stable and inducible PLCγ1 down-regulation can inhibit formation of breast-cancer-derived experimental lung metastasis. Further, high expression of PLCγ1 and its constitutively activated forms (i.e., PLCγ1-pY1253, PLCγ1-pY783) is associated with worse clinical outcome in terms of incidence of distant metastases, but not of local relapse in T1-T2, N0 breast cancer patients. METHODS: In the present retrospective study, we analysed the prognostic role of PLCγ1 in early breast cancer patients stratified according to the St. Gallen criteria and to their menopausal status. PLCγ1-pY1253 and PLCγ1-pY783 protein expression levels were determined by immunohistochemistry on tissue microarrays, and were correlated with patients' clinical data, using univariate and multivariate statistical analyses. RESULTS: In our series, the prognostic value of PLCγ1 overexpression was restricted to Luminal type tumours. From multivariate analyses, pY1253-PLCγ1High was an independent prognostic factor only in postmenopausal patients with Luminal-B tumours (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.1-5.3; P = 0.034). Conversely, PLCγ1-pY783High was a remarkably strong risk factor (HR, 20.1; 95% CI, 2.2-178.4; P = 0.003) for pre/perimenopausal patients with Luminal-A tumours. CONCLUSIONS: PLCγ1 overexpression is a strong predictive surrogate marker of development of metastases in early Luminal-A and -B breast cancer patients, being able to discriminate patients with high and low risk of metastases. Therefore, targeting the PLCγ1 pathway can be considered of potential benefit for prevention of metastatic disease.

Vav1 downmodulates Akt in different breast cancer subtypes: a new promising chance to improve breast cancer outcome.

Targeting different members of the Akt pathways is a promising therapeutic chance in solid tumors including breast cancer. The variable expression levels of Akt isoforms with opposite effects on tumor growth and metastasis, however, make it difficult to select the inhibitors to be used for specific breast tumor subtypes. Using in vitro and in vivo models, we demonstrated here that Vav1, ectopically expressed in invasive breast tumors derived cells, downmodulates Akt acting at expression and/or activation levels depending on tumor subtype. The decreased p-Akt1 (Ser473) levels are a common effect of Vav1 upmodulation, suggesting that, in breast tumor-derived cells and independently of their phenotype, Vav1 interferes with signaling pathways ended to specifically recruit Akt1. Only in ER-negative cell lines, the silencing of Vav1 induced the expression but not the activation of Akt2. A retrospective analysis of early invasive breast tumors allowed to establish the prognostic significance of the p-Akt/Vav1 relationship. In particular, low Vav1 levels negatively influence the follow-up of patients with low p-Akt in their primary tumors and subjected to adjuvant chemotherapy. As the use of specific or pan Akt inhibitors may not be sufficient or may even be detrimental, increasing the levels of Vav1 could be a new approach to improve breast cancer outcomes. This might be particularly relevant for tumors with a triple-negative phenotype, for which target-based therapies are not currently available.

Breast carcinomas with low amplified/equivocal HER2 by Ish: potential supporting role of multiplex ligation-dependent probe amplification.

BACKGROUND: This is a retrospective cross sectional study aimed to verify whether Multiplex Ligation-dependent Probe Amplification (MLPA), a quantitative molecular assay, may represent a valuable reflex test in breast cancer with equivocal HER2 expression by immunohistochemistry and HER2 gene signals/nucleus (s/n) ranging between 4.0 and 5.9 by in situ hybridization. METHODS: A series of 170 breast carcinomas scored as 2+ for HER2 expression by immunohistochemistry, were selected from our files and analyzed in parallel by silver in situ hybridization and by MLPA. According to ASCO-CAP 2013 guidelines, 54/170 tumors, displaying 4.0-5.9 HER2 gene s/n, were defined as low amplified (ratio ≥ 2) or equivocal (ratio < 2) on the basis of centromere enumeration probe 17 (CEP17) status. An independent set of 108 score 2+ breast cancers represented the external validation set. Concordance between the two techniques was assessed through the use of Cohen's K statistic. RESULTS: A concordance rate of 78.2% (Cohen's K statistic: 0,548 95% CI:[0,419-0,677]) between in situ hybridization and MLPA was found in the whole series of 170 cases and of 55.5% (Cohen's K statistic: -0,043 95% CI:[-0,271-0,184]) in the 54 tumors presenting 4.0-5.9 HER2 gene s/n. By MLPA, we found HER2 amplification or gain in 14% of the 21 BC presenting a disomic status and in 18% of the 33 BC presenting a CEP17 > 2.0. These data were further confirmed in the external validation set. Interestingly, the 54 low amplified/equivocal breast carcinomas presented a frequency of hormonal receptor positivity significantly higher than that observed in the amplified tumors and similar to the non-amplified one (p = 0.016 for estrogen receptor and p = 0.001 for progesterone receptor). CONCLUSIONS: To avoid to offer patients an ineffective therapy, HER2 status should be studied more thoroughly in low amplified and equivocal cases which can have lower response rates and shorter time to progression to trastuzumab. In this context, our data indicate that MLPA may be a reliable, objective supporting test in selecting HER2 positive breast cancer patients.

tsRNA signatures in cancer.

Small, noncoding RNAs are short untranslated RNA molecules, some of which have been associated with cancer development. Recently we showed that a class of small RNAs generated during the maturation process of tRNAs (tRNA-derived small RNAs, hereafter "tsRNAs") is dysregulated in cancer. Specifically, we uncovered tsRNA signatures in chronic lymphocytic leukemia and lung cancer and demonstrated that the ts-4521/3676 cluster (now called "ts-101" and "ts-53," respectively), ts-46, and ts-47 are down-regulated in these malignancies. Furthermore, we showed that tsRNAs are similar to Piwi-interacting RNAs (piRNAs) and demonstrated that ts-101 and ts-53 can associate with PiwiL2, a protein involved in the silencing of transposons. In this study, we extended our investigation on tsRNA signatures to samples collected from patients with colon, breast, or ovarian cancer and cell lines harboring specific oncogenic mutations and representing different stages of cancer progression. We detected tsRNA signatures in all patient samples and determined that tsRNA expression is altered upon oncogene activation and during cancer staging. In addition, we generated a knocked-out cell model for ts-101 and ts-46 in HEK-293 cells and found significant differences in gene-expression patterns, with activation of genes involved in cell survival and down-regulation of genes involved in apoptosis and chromatin structure. Finally, we overexpressed ts-46 and ts-47 in two lung cancer cell lines and performed a clonogenic assay to examine their role in cell proliferation. We observed a strong inhibition of colony formation in cells overexpressing these tsRNAs compared with untreated cells, confirming that tsRNAs affect cell growth and survival.

Expression of phosphorylated Hippo pathway kinases (MST1/2 and LATS1/2) in HER2-positive and triple-negative breast cancer patients treated with neoadjuvant therapy.

The Hippo kinases MST1/2 and LATS1/2 inhibit the oncoproteins TAZ/YAP and regulate T cell function. Hippo kinases also cooperate with the ATR-Chk1 and ATM-Chk2 pathways, central orchestrators of the DNA damage response (DDR). We hypothesized that MST1/2 and LATS1/2 localization differently impacts the efficacy of neoadjuvant therapy (NAT) in breast cancer, being protective when expressed in the cytoplasm of tumor cells and in tumor-infiltrating lymphocytes, whereas representing molecular determinants of chemoresistance when present in the nucleus as a consequence of their cooperation with the DDR. Diagnostic biopsies from 57 HER2-positive and triple-negative breast cancer patients treated with NAT were immunostained for evaluating the expression of phosphorylated MST1/2 (pMST1/2) and LATS1/2 (pLATS1/2) in tumor-infiltrating lymphocytes (TILs) and in cancer cells. TAZ and Chk1 immunostaining was exploited for investigating subcellular compartment-dependent activity of Hippo kinases. Nuclear pMST1/2 (pMST1/2nuc) expression was significantly associated with nuclear expression of Chk1 (p = 0.046), whereas cytoplasmic pMST1/2 (pMST1/2cyt) expression was marginally associated with cytoplasmic TAZ staining (p = 0.053). Patients whose tumors expressed pMST1/2nuc were at increased risk of residual disease after NAT (pCR ypT0/is ypN0: OR 4.91, 95%CI: 1.57-15.30; pCR ypT0 ypN0: OR 3.59, 95%CI 1.14-11.34). Conversely, exclusive cytoplasmic localization of pMST1/2 (pMST1/2cyt)seemed to be a protective factor (pCR ypT0/is ypN0: OR 0.34, 95%CI: 0.11-1.00; pCR ypT0 ypN0: OR 0.31, 95%CI 0.10-0.93). The subcellular localization-dependent significance of pMST1/2 expression suggests their involvement in different molecular networks with opposite impact on NAT efficacy. Larger studies are warranted to confirm these novel findings.

A cut-off of 2150 cytokeratin 19 mRNA copy number in sentinel lymph node may be a powerful predictor of non-sentinel lymph node status in breast cancer patients.

Since 2007, one-step nucleic acid amplification (OSNA) has been used as a diagnostic system for sentinel lymph node (SLN) examination in patients with breast cancer. This study aimed to define a new clinical cut-off of CK19 mRNA copy number based on the calculation of the risk that an axillary lymph node dissection (ALND) will be positive. We analyzed 1529 SLNs from 1140 patients with the OSNA assay and 318 patients with positive SLNs for micrometastasis (250 copies) and macrometastasis (5000 copies) underwent ALND. Axillary non-SLNs were routinely examined. ROC curves and Youden's index were performed in order to identify a new cut-off value. Logistic regression models were performed in order to compare OSNA categorical variables created on the basis of our and traditional cut-off to better identify patients who really need an axillary dissection. 69% and 31% of OSNA positive patients had a negative and positive ALND, respectively. ROC analysis identified a cut-off of 2150 CK19 mRNA copies with 95% sensitivity and 51% specificity. Positive and negative predictive values of this new cut-off were 47% and 96%, respectively. Logistic regression models indicated that the cut-off of 2150 copies better discriminates patients with node negative or positive in comparison with the conventional OSNA cut-off (p<0.0001). This cut-off identifies false positive and false negative cases and true-positive and true negative cases very efficiently, and therefore better identifies which patients really need an ALND and which patients can avoid one. This is why we suggest that the negative cut-off should be raised from 250 to 2150. Furthermore, we propose that for patients with a copy number that ranges between 2150 and 5000, there should be a multidisciplinary discussion concerning the clinical and bio-morphological features of primary breast cancer before any decision is taken on whether to perform an ALND or not.

Functional and prognostic significance of the genomic amplification of frizzled 6 (FZD6) in breast cancer.

Frizzled receptors mediate Wnt ligand signalling, which is crucially involved in regulating tissue development and differentiation, and is often deregulated in cancer. In this study, we found that the gene encoding the Wnt receptor frizzled 6 (FZD6) is frequently amplified in breast cancer, with an increased incidence in the triple-negative breast cancer (TNBC) subtype. Ablation of FZD6 expression in mammary cancer cell lines: (1) inhibited motility and invasion; (2) induced a more symmetrical shape of organoid three-dimensional cultures; and (3) inhibited bone and liver metastasis in vivo. Mechanistically, FZD6 signalling is required for the assembly of the fibronectin matrix, interfering with the organization of the actin cytoskeleton. Ectopic delivery of fibronectin in FZD6-depleted, triple-negative MDA-MB-231 cells rearranged the actin cytoskeleton and restored epidermal growth factor-mediated invasion. In patients with localized, lymph node-negative (early) breast cancer, positivity of tumour cells for FZD6 protein identified patients with reduced distant relapse-free survival. Multivariate analysis indicated an independent prognostic significance of FZD6 expression in TNBC tumours, predicting distant, but not local, relapse. We conclude that the FZD6-fibronectin actin axis identified in our study could be exploited for drug development in highly metastatic forms of breast cancer, such as TNBC. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Neoadjuvant Sequential Docetaxel Followed by High-Dose Epirubicin in Combination With Cyclophosphamide Administered Concurrently With Trastuzumab. The DECT Trial.

To report the results of the DECT trial, a phase II study of locally advanced or operable HER2-positive breast cancer (BC) treated with taxanes and concurrent anthracyclines and trastuzumab. Eligible patients (stage IIA-IIIB HER2-positive BC, 18-75 years, normal organ functions, ECOG ≤1, and left ventricular ejection fraction (LVEF) ≥55%) received four cycles of neoadjuvant docetaxel, 100 mg/m(2) intravenously, plus trastuzumab 6 mg/kg (loading dose 8 mg/kg) every 3 weeks, followed by four 3-weekly cycles of epirubicin 120 mg/m(2) and cyclophosphamide, 600 mg/m(2) , plus trastuzumab. Primary objective was pathologic complete response (pCR) rate, defined as ypT0/is ypN0 at definitive surgery. We enrolled 45 consecutive patients. All but six patients (13.3%) completed chemotherapy and all underwent surgery. pCR was observed in 28 patients (62.2%) overall and in 6 (66.7%) from the inflammatory subgroup. The classification and regression tree analysis showed a 100% pCR rate in patients with BMI ≥25 and with hormone negative disease. The median follow up was 46 months (8-78). Four-year recurrence-free survival was 74.7% (95%CI, 58.2-91.2). Seven patients (15.6%) recurred and one died. Treatment was well tolerated, with limiting toxicity being neutropenia. No clinical cardiotoxicity was observed. Six patients (13.4%) showed a transient LVEF decrease (<10%). In one patient we observed a ≥10% asymptomatic LVEF decrease persisting after surgery. Notwithstanding their limited applicability due to the current guidelines, our findings support the efficacy of the regimen of interest in the neoadjuvant setting along with a fairly acceptable toxicity profile, including cardiotoxicity. Results on BMI may invite further assessment in future studies. J. Cell. Physiol. 231: 2541-2547, 2016. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

Body Mass Index and Treatment Outcomes in Metastatic Breast Cancer Patients Treated With Eribulin.

Eribulin has shown survival advantage and manageable toxicity in heavily pre-treated metastatic breast cancer (mBC). We assessed whether body mass index (BMI) impacts treatment outcomes in 101 patients treated with eribulin at six Italian Oncologic Centers. BMI was addressed as a categorical variable (18.5-24.9 vs. at least 25). Clinical benefit rate (CBR) was assessed overall and in subgroups defined by BMI, line of therapy (LOT), and hormone receptor (HR) status. Analysis of CBR by LOT and HR status were further stratified by BMI. Survival curves were compared using the Kaplan-Meier method and log-rank test. Predictors of survival were tested in Cox models. Patients treated with eribulin as third line showed greater CBR when their BMI was in the lowest category (77.8 vs. 58.1%, P = 0.03). Median progression free survival (PFS) and overall survival (OS) in normal and overweight patients were 4 (95% CI, 3-5) versus 3 (2.1-4) months, P = 0.02 and 13 (11-15) versus 12 (6-18) months, P = 0.96, respectively. Median PFS and OS in estrogen receptor (ER) positive and negative tumours were 4 (3-5) versus 3 (2-4) months, P = 0.005 and 14 (10-18) versus 7 (4-10), P = 0.02, respectively. In multivariate analyses, BMI impacted PFS at a nearly significant extent (P = 0.05), while ER expression significantly affected PFS and OS (P = 0.01 and 0.02, respectively). No relevant findings emerged concerning toxicity. We found evidence of greater efficacy of eribulin in leaner mBC patients, particularly if given as third line and in ER positive tumors. Further studies are warranted to confirm our findings.