HER2-targeted therapy in breast cancer: a systematic review of neoadjuvant trials

Designing siRNA for silencing the human ERBB2 gene in cancer treatment: Evaluating intracellular delivery strategies

The ERBB2 is one of the most studied genes in oncology for its significant role in human malignancies. The metastasis-associated properties that facilitate cancer metastasis can be enhanced by activating the ERBB2 receptor signaling pathways. Additionally, therapeutic resistance is conferred by ERBB2 overexpression via receptor-mediated antiapoptotic signals. Several ERBB2-blocking techniques have the effect of overexpressed ERBB2, and several of them have passed clinical trials for use as therapies. Small interfering RNAs (siRNA), which have the potential to silence genes, are attractive for treating such fatal malignancies. In this study, we rationally designed a siRNA molecule targeting the human ERBB2 gene. The selection process involved identifying a shared region among all ERBB2 transcripts for siRNA design. The ultimate siRNA candidate was chosen through rigorous evaluation using contemporary algorithms, considering off-target similarities, examination of thermodynamic properties, and analysis using molecular dynamics (MD) simulations. Further, we opted for cell-penetrating peptides (CPP) and RNA aptamer as carriers for the siRNA. Employing both steered MD simulations and traditional MD simulations, we investigated how these carriers facilitate siRNA delivery. Experimental confirmation revealed the stability of the selected carriers and siRNA on the lipid bilayer. The designed siRNA molecule and the simulations present a potential alternative therapeutic strategy against human ERBB2. This contributes to advances in developing and utilizing innovative carriers for the delivery of siRNA, enhancing the potential for therapeutic applications.

p53R172H and p53R245W Hotspot Mutations Drive Distinct Transcriptomes in Mouse Mammary Tumors Through a Convergent Transcriptional Mediator

Aggressive breast cancers harbor TP53 missense mutations. Tumor cells with TP53 missense mutations exhibit enhanced growth and survival through transcriptional rewiring. To delineate how TP53 mutations in breast cancer contribute to tumorigenesis and progression in vivo, we created a somatic mouse model driven by mammary epithelial cell-specific expression of Trp53 mutations. Mice developed primary mammary tumors reflecting the human molecular subtypes of luminal A, luminal B, HER2-enriched, and triple-negative breast cancer with metastases. Transcriptomic analyses comparing MaPR172H/- or MaPR245W/- mammary tumors to MaP-/- tumors revealed (1) differences in cancer-associated pathways activated in both p53 mutants and (2) Nr5a2 as a novel transcriptional mediator of distinct pathways in p53 mutants. Meta-analyses of human breast tumors corroborated these results. In vitro assays demonstrate mutant p53 upregulates specific target genes that are enriched for Nr5a2 response elements in their promoters. Co-immunoprecipitation studies revealed p53R172H and p53R245W interact with Nr5a2. These findings implicate NR5A2 as a novel mediator of mutant p53 transcriptional activity in breast cancer.

SIGNIFICANCE

Our findings implicate NR5A2 as a novel mediator of mutant p53 transcriptional activity in breast cancer. NR5A2 may be an important therapeutic target in hard-to-treat breast cancers such as endocrine-resistant tumors and metastatic triple-negative breast cancers harboring TP53 missense mutations.

Evolving Management of Breast Cancer in the Era of Predictive Biomarkers and Precision Medicine

Breast cancer is the most common cancer among women in the world as well as in the United States. Molecular and histological differentiation have helped clinicians optimize treatments with various therapeutics, including hormonal therapy, chemotherapy, immunotherapy, and radiation therapy. Recently, immunotherapy has become the standard of care in locally advanced triple-negative breast cancer and an option across molecular subtypes for tumors with a high tumor mutation burden. Despite the advancements in personalized medicine directing the management of localized and advanced breast cancers, the emergence of resistance to these therapies is the leading cause of death among breast cancer patients. Therefore, there is a critical need to identify and validate predictive biomarkers to direct treatment selection, identify potential responders, and detect emerging resistance to standard therapies. Areas of active scientific and clinical research include novel personalized and predictive biomarkers incorporating tumor microenvironment, tumor immune profiling, molecular characterization, and histopathological differentiation to predict response and the potential emergence of resistance.

Synergistic therapeutic potential of alpelisib in cancers (excluding breast cancer): Preclinical and clinical evidences

The phosphoinositide 3-kinase (PI3K) signaling pathway is well-known for its important role in cancer growth, proliferation and migration. The activation of PI3K pathway is always connected with endocrine resistance and poor prognosis in cancers. Alpelisib, a selective inhibitor of PI3K, has been demonstrated to be effective in combination with endocrine therapy in HR+ PIK3CA-mutated advanced breast cancer in preclinical and clinical trials. Recently, the synergistic effects of alpelisib combined with targeted agents have been widely reported in PIK3CA-mutated cancer cells, such as breast, head and neck squamous cell carcinoma (HNSCC), cervical, liver, pancreatic and lung cancer. However, previous reviews mainly focused on the pharmacological activities of alpelisib in breast cancer. The synergistic therapeutic potential of alpelisib in other cancers has not yet been well reviewed. In this review, an extensive study of related literatures (published until December 20, 2022) regarding the anti-cancer functions and synergistic effects of alpelisib was carried out through the databases. Useful information was extracted. We summarized the preclinical and clinical studies of alpelisib in combination with targeted anti-cancer agents in cancer treatment (excluding breast cancer). The combinations of alpelisib and other targeted agents significantly improved the therapeutic efficacy both in preclinical and clinical studies. Unfortunately, synergistic therapies still could not effectively avoid the possible toxicities and adverse events during treatment. Finally, some prospects for the combination studies in cancer treatment were provided in the paper. Taken together, this review provided valuable information for alpelisib in preclinical and clinical applications.

PIK3CA mutations are associated with pathologic complete response rate to neoadjuvant pyrotinib and trastuzumab plus chemotherapy for HER2-positive breast cancer

BACKGROUND

Neoadjuvant treatment with a dual anti-human epidermal growth factor receptor 2 (HER2) blockade with pyrotinib and trastuzumab has been shown to be effective for HER2-positive breast cancer.

METHODS

The genomic characteristics of 425 cancer-related genes from the archived tumour blocks of 50 patients enrolled in a prospective neoadjuvant pyrotinib and trastuzumab plus chemotherapy clinical trial (ChiCTR1900022293) were assessed by next-generation sequencing (NGS). The relationship between tumour biomarkers and the postoperative pathological complete response (pCR) were explored.

RESULTS

Forty-five patients completed neoadjuvant chemotherapy and final surgery, of which 26 (58%) achieved a pCR. Among all driver gene mutations, PIK3CA mutation was screened out for having a significant relationship with the treatment response. The pCR rate of patients with wild-type PIK3CA was significantly higher than patients with mutated PIK3CA (80.8% vs. 26.3%; P = 0.00057), and remained significant after a multiple comparison adjustment (P_adjusted = 0.024). We further evaluated the predictive value with logistic regression model of clinical features, genetic biomarkers or both, an AUC of 0.912 (95% CI: 0.827-0.997) was achieved in the integrated model.

CONCLUSIONS

Our data suggest that HER2-positive breast cancers with activating mutations in PIK3CA are less likely to benefit from pyrotinib combined with trastuzumab neoadjuvant therapy.

Branched, dendritic, and hyperbranched polymers in liquid biopsy device design

The development of minimally invasive tests for cancer diagnosis and prognosis will aid in the research of new treatments and improve survival rates. Liquid biopsies seek to derive actionable information from tumor material found in routine blood samples. The relative scarcity of tumor material in this complex mixture makes isolating and detecting cancerous material such as proteins, circulating tumor DNA, exosomes, and whole circulating tumor cells a challenge for device engineers. This review describes the chemistry and applications of branched and hyperbranched to improve the performance of liquid biopsy devices. These polymers can improve the performance of a liquid biopsy through several mechanisms. For example, polymers designed to increase the affinity of capture enhance device sensitivity. On the other hand, polymers designed to increase binding avidity or repel nonspecific adsorption enhance device specificity. Branched and hyperbranched polymers can also be used to amplify the signal from small amounts of detected material. The further development of hyperbranched polymers in liquid biopsy applications will enhance device capabilities and help these critical technologies reach the oncology clinic where they are sorely needed. This article is categorized under: Diagnostic Tools > Biosensing Diagnostic Tools > Diagnostic Nanodevices.

Comparing Biomarkers for Predicting Pathological Responses to Neoadjuvant Therapy in HER2-Positive Breast Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

The predictive strength and accuracy of some biomarkers for the pathological complete response (pCR) to neoadjuvant therapy for HER2-positive breast cancer remain unclear. This study aimed to compare the accuracy of the HER2-enriched subtype and the presence of PIK3CA mutations, namely, TILs, HRs, and Ki-67, in predicting the pCR to HER2-positive breast cancer therapy.

METHODS

We screened studies that included pCR predicted by one of the following biomarkers: the HER2-enriched subtype and the presence of PIK3CA mutations, TILs, HRs, or Ki-67. We then calculated the pooled sensitivity, specificity, positive and negative predictive values (PPVs and NPVs, respectively), and positive and negative likelihood ratios (LRs). Summary receiver operating characteristic (SROC) curves and areas under the curve (AUCs) were used to estimate the diagnostic accuracy.

RESULTS

The pooled estimates of sensitivity and specificity for the HER2-enriched subtype and the presence of PIK3CA mutations, namely, TILs, HRs, and Ki-67, were 0.66 and 0.62, 0.85 and 0.27, 0.49 and 0.61, 0.54 and 0.64, and 0.68 and 0.51, respectively. The AUC of the HER2-enriched subtype was significantly higher (0.71) than those for the presence of TILs (0.59, p = 0.003), HRs (0.65, p = 0.003), and Ki-67 (0.62, p = 0.005). The AUC of the HER2-enriched subtype had a tendency to be higher than that of the presence of PIK3CA mutations (0.58, p = 0.220). Moreover, it had relatively high PPV (0.58) and LR+ (1.77), similar NPV (0.73), and low LR- (0.54) compared with the other four biomarkers.

CONCLUSIONS

The HER2-enriched subtype has a moderate breast cancer diagnostic accuracy, which is better than those of the presence of PIK3CA mutations, TILs, HRs, and Ki-67.

CHIP/STUB1 Ubiquitin Ligase Functions as a Negative Regulator of ErbB2 by Promoting Its Early Post-Biosynthesis Degradation

Simple Summary

Overexpressed ErbB2/HER2 receptor drives up to a quarter of breast cancers. One aspect of ErbB2 biology that is poorly understood is how it reaches the cell surface following biosynthesis in the endoplasmic reticulum (ER). Here, the authors show that the CHIP (C-terminus of HSC70-Interacting protein)/STUB1 (STIP1-homologous U-Box containing protein 1) protein targets the newly synthesized ErbB2 for ubiquitin/proteasome-dependent degradation in the ER and Golgi, identifying a novel mechanism that negatively regulates cell surface expression of ErbB2. These findings provide one explanation for frequent loss of CHIP expression is ErbB2-overexpressing breast cancers. The authors further show that ErbB2-overexpressing breast cancer cells with low CHIP expression exhibit higher ER stress inducibility, and ER stress-inducing anticancer drug Bortezomib synergizes with ErbB2-targeted humanized antibody Trastuzumab to inhibit cancer cell proliferation. These new insights suggest that reduced CHIP expression may specify ErbB2-overexpressing breast cancers suitable for combined treatment with Trastuzumab and ER stress inducing agents.

Abstract

Overexpression of the epidermal growth factor receptor (EGFR) family member ErbB2 (HER2) drives oncogenesis in up to 25% of invasive breast cancers. ErbB2 expression at the cell surface is required for oncogenesis but mechanisms that ensure the optimal cell surface display of overexpressed ErbB2 following its biosynthesis in the endoplasmic reticulum are poorly understood. ErbB2 is dependent on continuous association with HSP90 molecular chaperone for its stability and function as an oncogenic driver. Here, we use knockdown and overexpression studies to show that the HSP90/HSC70-interacting negative co-chaperone CHIP (C-terminus of HSC70-Interacting protein)/STUB1 (STIP1-homologous U-Box containing protein 1) targets the newly synthesized, HSP90/HSC70-associated, ErbB2 for ubiquitin/proteasome-dependent degradation in the endoplasmic reticulum and Golgi, thus identifying a novel mechanism that negatively regulates cell surface ErbB2 levels in breast cancer cells, consistent with frequent loss of CHIP expression previously reported in ErbB2-overexpressing breast cancers. ErbB2-overexpressing breast cancer cells with low CHIP expression exhibited higher endoplasmic reticulum stress inducibility. Accordingly, the endoplasmic reticulum stress-inducing anticancer drug Bortezomib combined with ErbB2-targeted humanized antibody Trastuzumab showed synergistic inhibition of ErbB2-overexpressing breast cancer cell proliferation. Our findings reveal new insights into mechanisms that control the surface expression of overexpressed ErbB2 and suggest that reduced CHIP expression may specify ErbB2-overexpressing breast cancers suitable for combined treatment with Trastuzumab and ER stress inducing agents.

Prediction of Late Recurrence and Distant Metastasis in Early-stage Breast Cancer: Overview of Current and Emerging Biomarkers

Recently, a significant number of breast cancer (BC) patients have been diagnosed at an early stage. It is therefore critical to accurately predict the risk of recurrence and distant metastasis for better management of BC in this setting. Clinicopathologic patterns, particularly lymph node status, tumor size, and hormonal receptor status are routinely used to identify women at increased risk of recurrence. However, these factors have limitations regarding their predictive ability for late metastasis risk in patients with early BC. Emerging molecular signatures using gene expression-based approaches have improved the prognostic and predictive accuracy for this indication. However, the use of their based-scores for risk assessment has provided contradictory findings. Therefore, developing and using newly emerged alternative predictive and prognostic biomarkers for identifying patients at high- and low-risk is of great importance. The present review discusses some serum biomarkers and multigene profiling scores for predicting late recurrence and distant metastasis in early-stage BC based on recently published studies and clinical trials.

White blood cell subsets in HER2-positive breast cancer patients treated with trastuzumab in relation to clinical outcome

To examine whether HER2+ breast cancer patients who have decreased immune effector cells could respond well to trastuzumab, we evaluated the alterations in circulating immune system cell subsets: CD16+ and/or CD56+ lymphocytes, lymphocytes and granulocytes in these patients before and after treatment with trastuzumab-based regimens in relation to clinical response to therapy. The study involved 55 patients with HER2+ breast cancer before and 2 months after the initiation of the therapy. Progressive disease was confirmed in nine out of 55 patients (non-responders), while other patients achieved complete or partial response, or stable disease (responders). Control group consisted of up to 52 healthy individuals. Significantly lower percentages of total lymphocytes, CD16+, CD56+, and CD16+CD56+ lymphocytes as well as higher percentage of granulocytes and a higher ratio of granulocyte to lymphocyte percentages were found in patients before therapy and 2 months after the initiation of the therapy, compared with those in healthy individuals. Responder subgroup showed significantly lower percentages of CD16+, CD56+, and CD16+CD56+ lymphocytes before therapy, compared with those in healthy controls. Two months after the initiation of the therapy, the percentages of immune cell subsets remained significantly lower in responders in comparison with those in the healthy donors, while a significantly decreased percentages of CD56+ and CD16+CD56+ lymphocytes were observed in non-responders, in comparison with those in healthy controls. Our study demonstrated that HER2+ breast cancer patients who have decreased percentages of CD16+, CD56+, and CD16+CD56+ lymphocytes may achieve response to trastuzumab-containing treatment.

Phase II study of liposomal doxorubicin, docetaxel and trastuzumab in combination with metformin as neoadjuvant therapy for HER2-positive breast cancer

BACKGROUND

The aim of this study was to improve activity over single human epidermal growth factor receptor 2 (HER2)-blockade sequential neaodjuvant regimens for HER2-positive breast cancer, by exploiting the concomitant administration of trastuzumab, taxane and anthracycline, while restraining cardiac toxicity with use of liposomal doxorubicin, and by adding metformin, based on preliminary evidence of antitumor activity.

PATIENTS AND METHODS

This multi-center, single-arm, two-stage phase II trial, assessed the safety and the activity of a new treatment regimen for HER2-positive, early or locally advanced breast cancer. Patients received six 21-day cycles of non-pegylated liposomal doxorubicin, 50 mg/m2 intravenously (i.v.) on day 1, docetaxel, 30 mg/m2 i.v. on days 2 and 9, trastuzumab, 2 mg/kg/week i.v. on days 2, 9, and 16 (with 4 mg/kg loading dose), in association with metformin 1000 mg orally twice daily. The primary endpoint was the rate of pathological complete response (pCR) in the breast and axilla (ypT0/is ypN0). A subgroup of patients performed a 3-deoxy-3-18F-fluorothymidine positron emission tomography (FLT-PET) at baseline and after one cycle.

RESULTS

Among 47 evaluable patients, there were 18 pCR [38.3%, 95% confidence interval (CI) 24.5-53.6%]. A negative estrogen-receptor status, high Ki67, and histological grade 3 were related with pCR, although only grade reached statistical significance. FLT-PET maximum standardized uptake value after one cycle was inversely related to pCR in the breast (odds ratio 0.29, 95% CI 0.06-1.30, p = 0.11). Toxicity included grade 3-4 neutropenia in 70% and febrile neutropenia in 4% of patients, grade 1-2 nausea/vomiting in 60%/38%, and grade 3 in 4%/2%, respectively, grade 1-2 diarrhea in 72%, and grade 3 in 6%. There were two cases of reversible grade 2 left-ventricular ejection-fraction decrease, and one case of sharp troponin-T increase.

CONCLUSIONS

The concomitant administration of trastuzumab, liposomal doxorubicin, docetaxel, and metformin is safe and shows good activity, but does not appear to improve activity over conventional sequential regimens.

Current Biomarkers for Precision Medicine in Breast Cancer

Breast cancer has become the prototypical solid tumor where targets have been identified within the tumor allowing for personalized approach for systemic therapy. Biomarkers are beginning to play an important role in preparing the way for precision treatment. Mandatory biomarkers for every newly diagnosed case of breast cancer are estrogen receptors and progesterone receptors in selecting patients for endocrine treatment and HER2 for identifying patients likely to benefit from antiHER2 therapy. Although methodological problems exist in the determination of Ki67, because of its clearly established clinical value, wide availability, and low costs relative to the available multianalyte signatures, Ki67 may be used for determining prognosis, especially if values are low or high. Also, the androgen receptor (AR) pathway is emerging as a potential therapeutic target in breast cancer. AR-targeted treatments for breast cancer are in development and have shown promising preliminary results. While, most established biomarkers in breast cancer require tissue samples, serum tumor markers are easily accessible and require a less invasive procedure. Among them, tissue polypeptide-specific antigen (TPS), a specific epitope structure of a peptide in serum associated with human cytokeratin 18, is linked to the proliferative activity of tumors. TPS may be a valuable and independent prognostic biomarker for breast cancer.In order to accelerate progress towards precision treatment for women with breast cancer, we need additional predictive biomarker, especially for enhancing the positive predictive value for endocrine and antiHER2 therapies, as well as biomarkers for predicting response to specific forms of chemotherapy.

Health-related quality of life and work productivity in UK patients with HER2-positive breast cancer: a cross-sectional study evaluating the relationships between disease and treatment stage

BACKGROUND

The impact of different disease stages and treatment for human epidermal growth factor 2 positive (HER2-positive) breast cancer (BC) on work productivity and health-related quality of life (HRQoL) is poorly understood.

METHODS

This was a UK cross-sectional study of 299 adult patients with HER2-positive early or metastatic BC (NCT03099200). Productivity was assessed using the work productivity and activity impairment scale; HRQoL was measured using EuroQol-5 Dimensions-5 levels (EQ-5D-5L), and Functional Assessment of Cancer Therapy Breast (FACT-G and -B) instruments. Three balanced patient groups were recruited: (1) early BC on treatment post-surgery, (2) early BC after completion of adjuvant treatment, (3) during metastatic BC treatment. Between-group comparisons were performed using an analysis of variance.

RESULTS

Group 1 comprised 89 patients, Group 2, 108 and Group 3, 102. Age, ethnicity and comorbidities were similar across groups. Patients in Group 3 reported more often being unable to work (significant Bonferroni adjusted p < 0.003). Proportions of employed patients were 50.6%, 50.9% and 27.5% in Groups 1, 2 and 3, respectively. For patients in part-time employment, the number of hours worked was significantly higher in Group 2 patients versus Group 3 (p = 0.002). Group 2 also had significantly lower levels of work absenteeism and overall work impairment compared with Group 1 (p < 0.001). Patients in Group 3 reported worse health utility scores (p ≤ 0.002), moderate or worse problems in the EQ-5D-5L self-care and usual activity domains (p ≤ 0.001), and lower HRQoL as assessed by FACT summary scores (p < 0.001 for FACT-B and -G) than Groups 1 and 2. Poorer HRQoL was significantly associated with higher work impairment (p < 0.001), with the strongest relationships being observed between activity impairment and HRQoL (Pearson's r: 0.67).

CONCLUSIONS

Metastatic disease and treatment of HER2-positive BC adversely impacted on work productivity and HRQoL. The results of this study support the idea that being able to delay or prevent the metastatic recurrence of BC, for example by extending the time patients are in remission or at early stage of BC, has wider benefits in terms of patient productivity and HRQoL.

Rapid Target Binding and Cargo Release of Activatable Liposomes Bearing HER2 and FAP Single-Chain Antibody Fragments Reveal Potentials for Image-Guided Delivery to Tumors

Liposomes represent suitable tools for the diagnosis and treatment of a variety of diseases, including cancers. To study the role of the human epidermal growth factor receptor 2 (HER2) as target in cancer imaging and image-guided deliveries, liposomes were encapsulated with an intrinsically quenched concentration of a near-infrared fluorescent dye in their aqueous interior. This resulted in quenched liposomes (termed LipQ), that were fluorescent exclusively upon degradation, dye release, and activation. The liposomes carried an always-on green fluorescent phospholipid in the lipid layer to enable tracking of intact liposomes. Additionally, they were functionalized with single-chain antibody fragments directed to fibroblast activation protein (FAP), a marker of stromal fibroblasts of most epithelial cancers, and to HER2, whose overexpression in 20–30% of all breast cancers and many other cancer types is associated with a poor treatment outcome and relapse. We show that both monospecific (HER2-IL) and bispecific (Bi-FAP/HER2-IL) formulations are quenched and undergo HER2-dependent rapid uptake and cargo release in cultured target cells and tumor models in mice. Thereby, tumor fluorescence was retained in whole-body NIRF imaging for 32–48 h post-injection. Opposed to cell culture studies, Bi-FAP/HER2-IL-based live confocal microscopy of a high HER2-expressing tumor revealed nuclear delivery of the encapsulated dye. Thus, the liposomes have potentials for image-guided nuclear delivery of therapeutics, and also for intraoperative delineation of tumors, metastasis, and tumor margins.

Multi-omics analyses identify HSD17B4 methylation-silencing as a predictive and response marker of HER2-positive breast cancer to HER2-directed therapy

HER2-positive breast cancers that achieve pathological complete response (pCR) after HER2-directed therapy consistently have good survival. We previously identified HSD17B4 methylation as a marker for pCR by methylation screening. Here, we aimed to identify a new marker by conducting a multi-omics analysis of materials prepared by laser capture microdissection, and adding 71 new samples. In the screening set (n = 36), mutations, methylation, and expression were analyzed by targeted sequencing, Infinium 450 K, and expression microarray, respectively, and 15 genes were identified as differentially expressed and eight genomic regions as differentially methylated between cancer samples with and without pCR. In a validation set (n = 47), one gene showed differential expression, and one region had differential methylation. Further, in the re-validation set (n = 55), all new samples, only HSD17B4 methylation was significantly different. The HSD17B4 methylation was at the transcriptional start site of its major variant, and was associated with its silencing. HSD17B4 was highly expressed in the vast majority of human cancers, and its methylation was present only in breast cancers and one lymphoblastic leukemia cell line. A combination of estrogen receptor-negative status and HSD17B4 methylation showed a positive predictive value of 80.0%. During HER2-directed neoadjuvant therapy, HSD17B4 methylation was the most reliable marker to monitor response to the therapy. These results showed that HSD17B4 methylation is a candidate predictive and response marker of HER2-positive breast cancer to HER2-directed therapy.

Prognostic Value of HER2 to CEP17 Ratio on Fluorescence In Situ Hybridization Ratio in Patients with Nonmetastatic HER2-Positive Inflammatory and Noninflammatory Breast Cancer Treated with Neoadjuvant Chemotherapy with or without Trastuzumab

BACKGROUND

We previously reported that in patients with HER2-positive (HER2+) locally advanced breast cancer treated with neoadjuvant trastuzumab-containing regimens, high HER2 to centromere enumerator probe 17 ratio on fluorescence in situ hybridization (HER2 FISH ratio) was an independent predictor of high pathologic complete response (pCR) rate, which translated into improved recurrence-free survival (RFS). We sought to determine whether high HER2 FISH ratio is a predictor of pCR and prognosis in patients with HER2+ nonmetastatic inflammatory breast cancer (IBC) and non-IBC treated with neoadjuvant chemotherapy with or without trastuzumab.

MATERIALS AND METHODS

This study included all patients with histologically proven stage III, HER2+ primary IBC, and non-IBC treated with neoadjuvant chemotherapy with or without trastuzumab and definitive surgery during 1999-2012. Univariate and multivariate logistic regression models were applied to assess the effect of covariates on pCR. Kaplan-Meier estimates with log-rank test were employed for survival analysis. Univariate and multivariate Cox proportional hazards models were used to assess the effect of covariates on RFS and overall survival (OS).

RESULTS

The study included 555 patients with stage III, HER+ breast cancer, 181 patients with IBC, and 374 with non-IBC. In the IBC cohort, HER2 FISH ratio was not significantly associated with pCR, RFS, or OS. In the non-IBC cohort, higher HER2 FISH ratio was significantly associated with higher pCR rate and longer OS.

CONCLUSION

HER2 FISH ratio showed prognostic value among patients with HER2+ non-IBC but not HER2+ IBC treated with neoadjuvant chemotherapy. This disparity may be due to the underlying aggressive nature of IBC.

IMPLICATIONS FOR PRACTICE

The findings of this study indicate that the HER2 to fluorescence in situ hybridization ratio as a continuous variable has promise as a predictor of pathologic complete response to neoadjuvant chemotherapy in patients with HER2-positive (HER2+) noninflammatory breast cancer (non-IBC) regardless of the results on HER2 immunohistochemical testing. In the future, some patients with HER2+ non-IBC and a high HER2 FISH ratio might even be offered personalized treatment options, such as nonsurgical treatment.

Pathologic complete response and overall survival in breast cancer subtypes in stage III inflammatory breast cancer

Purpose

To analyze the influence of hormone receptors (HR) and Human Epidermal growth factor Receptor-2 (HER2)-based molecular subtypes in stage III inflammatory breast cancer (IBC) on tumor characteristics, treatment, pathologic response to neoadjuvant chemotherapy (NACT), and overall survival (OS).

Methods

Patients with stage III IBC, diagnosed in the Netherlands between 2006 and 2015, were classified into four breast cancer subtypes: HR+/HER2− , HR+/HER2+ , HR−/HER2+ , and HR−/HER2− . Patient-, tumor- and treatment-related characteristics were compared. In case of NACT, pathologic complete response (pCR) was compared between subgroups. OS of the subtypes was compared using Kaplan–Meier curves and the log-rank test.

Results

1061 patients with stage III IBC were grouped into subtypes: HR+/HER2− (N = 453, 42.7%), HR−/HER2− (N = 258, 24.3%), HR−/HER2+ (N = 180,17.0%), and HR+/HER2+ (N = 170,16.0%). In total, 679 patients (85.0%) received NACT. In HR−/HER2+ tumors, pCR rate was highest (43%, (p < 0.001). In case of pCR, an improved survival was observed for all subtypes, especially for HR+/HER2+ and HR−/HER2+ tumor subtypes. Trimodality therapy (NACT, surgery, radiotherapy) improved 5-year OS as opposed to patients not receiving this regimen: HR+/HER2− (74.9 vs. 46.1%), HR+/HER2+ (80.4 vs. 52.6%), HR−/HER2+ (76.4 vs. 29.7%), HR−/HER2− (47.6 vs. 27.8%).

Conclusions

In stage III IBC, breast cancer subtypes based on the HR and HER2 receptor are important prognostic factors of response to NACT and OS. Patients with HR−/HER2− IBC were less likely to achieve pCR and had the worst OS, irrespective of receiving most optimal treatment regimen to date (trimodality therapy).

Adjuvant Chemotherapy Guidance in Young Breast Cancer Patients With Luminal Subtypes and Stage pT1N0

BACKGROUND

This study evaluated whether young breast cancer patients (≤ 40 y of age) with luminal subtypes and stage pT1N0 can benefit from chemotherapy (CHT).

MATERIALS AND METHODS

This study included 688 patients aged ≤ 40 y with luminal subtypes and stage pT1N0 breast cancer. The overall survival and disease-free survival (DFS) rates in the whole cohort and subgroups were compared between patients receiving CHT followed by endocrinotherapy (ET) (CHT→ET group) and those receiving only ET (ET-alone group).

RESULTS

Univariate analysis identified that the tumors in the CHT→ET group were more aggressive than those in the ET-alone group. However, the overall survival and DFS rates did not differ significantly between the CHT→ET and ET-alone groups (P = 0.416 and 0.21, respectively), implying that a subgroup of patients could benefit from CHT. Subgroup analysis of DFS rates revealed that patients with human epidermal growth factor receptor 2 overexpression (P = 0.042), histological classification grade 3 (P = 0.030), progesterone receptor ≤ 20% (P = 0.033), and clinical stage T1c (P = 0.038) could benefit from CHT. Further analysis showed that these four risk factors combined predicted whether the patient could benefit from CHT.

CONCLUSIONS

Young patients with hormone receptor-positive and stage pT1N0 breast cancer may benefit from CHT only if they exhibit at least two of the following risk factors: progesterone receptor ≤ 20%, human epidermal growth factor receptor 2 overexpression, histological grading 3, or clinical stage T1c.

Conditional knockout of SHP2 in ErbB2 transgenic mice or inhibition in HER2-amplified breast cancer cell lines blocks oncogene expression and tumorigenesis

Overexpression of the human epidermal growth factor receptor 2 (HER2) is the cause of HER2-positive breast cancer (BC). Although HER2-inactivating therapies have benefited BC patients, development of resistance and disease recurrence have been the major clinical problems, pointing to a need for alternative therapeutic strategies. For that to happen, proteins that play critical roles in the biology of HER2-induced tumorigenesis have to be identified and characterized. Here, we show that the Src homology phosphotyrosyl phosphatase 2 (Shp2) encoded by the Ptpn11 gene is a requisite for ErbB2-induced tumorigenesis. We report that conditional knockout of Shp2 alleles in the ErbB2 BC model mice abrogates mammary tumorigenesis by blocking the expression of the ErbB2 transgene. We also show that inhibition of SHP2 encoded by the PTPN11 gene in the HER2-amplified BC cells induces a normal-like cellular phenotype and suppresses tumorigenesis and metastasis by blocking HER2 overexpression. These findings demonstrate that ErbB2-induced tumors in mice or xenograft tumors induced by transplantation of HER2-amplified BC cells are vulnerable to SHP2 inhibition since it abrogates the expression of the very oncogene that causes of the disease. This report paves the way for developing SHP2-targeting therapies for BC treatment in the future.

miR-182 regulates trastuzumab resistance by targeting MET in breast cancer cells

It has been found that microRNAs (miRNAs) play a key role in drug resistance. The purpose of the current study was to investigate the function of miR-182 in trastuzumab resistance in breast cancer cells. The results showed that both breast cancer SKBR3 trastuzumab-resistant cells (SKBR3/TR) and BT474 trastuzumab-resistant cells (BT474/TR) were associated with miR-182 downregulation compared with their parental cells. Ectopic expression of the miR-182 mimic inhibited trastuzumab resistance, decreasing the invasion and migration of these trastuzumab-resistant cells. However, the miR-182 inhibitor increased trastuzumab resistance, cell invasion, and migration in the parental cells. In addition, MET is a directly targeted gene of miR-182 in breast cancer cells. MET knockdown showed an inhibitory effect of trastuzumab resistance on trastuzumab-resistant cells. In contrast, MET overexpression in SKBR3 cells produced an effect that promotes resistance to trastuzumab. Moreover, we revealed that overexpression of miR-182 reduced trastuzumab resistance in trastuzumab-resistant cells due in part to MET/PI3K/AKT/mTOR signaling pathway inactivation. Furthermore, miR-182 could also sensitize SKBR3/TR cells to trastuzumab in vivo. In conclusion, our results suggest that the activation of miR-182 or inactivation of its target gene pathway could be used as a new method to reverse trastuzumab resistance in breast cancer.

A novel detection methodology for HER2 protein quantitation in formalin-fixed, paraffin embedded clinical samples using fluorescent nanoparticles: an analytical and clinical validation study

BACKGROUND

Clinical assays for the assessment of the human epidermal growth factor receptor-2 (HER2) status in breast cancer include immunohistochemistry (IHC) and in situ hybridization (ISH), both of which have limitations. Recent studies have suggested that a more quantitative approach to the measurement of HER2 protein expression may improve specificity in selecting patients for HER-2 targeted therapy. In the current study, we have used HER2 expression in breast cancer cell lines and clinical samples as a model to explore the potential utility of a novel immunodetection technique, using streptavidin coated Phosphor Integrated Dot fluorescent nanoparticles (PID), which can be quantitatively measured using computer analysis.

METHODS

The expression of HER2 protein in cell lines was evaluated with antibody-binding capacity using fluorescence-activated cell sorting (FACS) for comparison with PID measurements to test for correlations with existing quantitative protein analysis methodologies. Various other analytic validation tests were also performed, including accuracy, precision, sensitivity, robustness and reproducibility. A methods comparison study investigated correlations between PID versus IHC and ISH in clinical samples. Lastly, we measured HER2 protein expression using PID in the pretreatment biopsies from 34 HER2-positive carcinomas that had undergone neoadjuvant trastuzumab-based chemotherapy.

RESULTS

In the analytic validation, PID HER2 measurements showed a strong linear correlation with FACS analysis in breast cell lines, and demonstrated significant correlations with all aspects of precision, sensitivity, robustness and reproducibility. PID also showed strong correlations with conventional HER2 testing methodologies (IHC and ISH). In the neoadjuvant study, patients with a pathologic complete response (pCR) had a significantly higher PID score compared with patients who did not achieve a pCR (p = 0.011), and was significantly correlated to residual cancer burden (RCB) class (p = 0.026, R² = 0.9975).

CONCLUSIONS

Analytic testing of PID showed that it may be a viable testing methodology that could offer advantages over other experimental or conventional biomarker diagnostic methodologies. Our data also suggests that PID quantitation of HER2 protein may offer an improvement over conventional HER2 testing in the selection of patients who will be the most likely to benefit from HER2-targeted therapy. Further studies with a larger cohort are warranted.

The evolving role of receptors as predictive biomarkers for metastatic breast cancer

INTRODUCTION

In breast cancer, estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) are essential biomarkers to predict response to endocrine and anti-HER2 therapies, respectively. In metastatic breast cancer, the use of these receptors and targeted therapies present additional challenges: temporal heterogeneity, together with limited sampling methodologies, hinders receptor status assessment, and the constant evolution of the disease invariably leads to resistance to treatment. Areas covered: This review summarizes the genomic abnormalities in ER and HER2, such as mutations, amplifications, translocations, and alternative splicing, emerging as novel biomarkers that provide an insight into underlying mechanisms of resistance and hold potential predictive value to inform treatment selection. We also describe how liquid biopsies for sampling of circulating markers and ultrasensitive detection technologies have emerged which complement ongoing efforts for biomarker discovery and analysis. Expert commentary: While evidence suggests that genomic aberrations in ER and HER2 could contribute to meeting the pressing need for better predictive biomarkers, efforts need to be made to standardize assessment methods and better understand the resistance mechanisms these markers denote. Taking advantage of emerging technologies, research in upcoming years should include prospective trials incorporating these predictors into the study design to validate their potential clinical value.

Doxorubicin conjugated with a trastuzumab epitope and an MMP-2 sensitive peptide linker for the treatment of HER2-positive breast cancer

HER2-positive breast cancer correlates with more aggressive tumor growth, a poorer prognosis and reduced overall survival. Currently, trastuzumab (Herceptin), which is an anti-HER2 antibody, is one of the key drugs. There is evidence indicating that conjugation of trastuzumab with chemotherapy drugs, such as doxorubicin (DOX), for multiple targets could be more effective. However, incomplete penetration into tumors has been noted for those conjugates. Compared to an antibody, peptides may represent an attractive alternative. For HER2, a similar potency has been observed for a 12-amino-acid anti-HER2 peptide mimetic YCDGFYACYMDV-NH₂ (AHNP, disulfide-bridged) and full-length trastuzumab. Thus, a peptide, GPLGLAGDDYCDGFYACYMDV-NH₂, which consists of AHNP and an MMP-2 cleavable linker GPLGLAGDD, was first designed, followed by conjugation with DOX via a glycine residue at the N-terminus to form a novel DOX-peptide conjugate MAHNP-DOX. Using HER2-positive human breast cancer cells BT474 and SKBR3 as in vitro model systems and nude mice with BT474 xenografts as an in vivo model, this conjugate was comprehensively characterized, and its efficacy was evaluated and compared with that of free DOX. As a result, MAHNP-DOX demonstrated a much lower in vitro IC₅₀, and its in vivo extent of inhibition in mice was more evident. During this process, enzymatic cleavage of MAHNP-DOX is critical for its activation and cellular uptake. In addition, a synergistic response was observed after the combination of DOX and AHNP. This effect was probably due to the involvement of AHNP in the PI3K–AKT signaling pathway, which can be largely activated by DOX and leads to anti-apoptotic signals.

A targeted immunotherapy approach for HER2/neu transformed tumors by coupling an engineered effector domain with interferon-γ

Despite substantial clinical progress with targeted therapies, current antibody-based approaches have limited efficacy at controlling HER2/neu-positive breast cancers, especially in the absence of chemotherapies. Previously, we showed that the combination of IFNγ and anti-HER2/neu antibody synergistically reduces tumor growth in an in vivo implanted mammary tumor model. Here, we report a recombinant approach to produce an anti-HER2/neu scFv and IFNγ fusion protein using an engineered effector domain (EED) scaffold. The new molecule induces in vitro apoptosis in an IFNγ receptor-dependent manner. At a very low dose in the in vivo xenografted tumor models, the new EED-IFNγ fusion protein demonstrates superior activity over the anti-HER2/neu antibody and is even active on tumors that are resistant to anti-HER2/neu antibody therapy. Examination of tumor infiltrated macrophages and lymphocytes reveals that the fusion protein can induce changes in tumor microenvironment to support immune reactivity against tumors. Our studies have defined a targeted immunotherapy approach for the treatment of cancers.

Inulanolide A as a new dual inhibitor of NFAT1-MDM2 pathway for breast cancer therapy

The transcription factor NFAT1 and the oncogene MDM2 have crucial roles in breast cancer development, progression, and metastasis. We have recently discovered that NFAT1 activates MDM2 expression. Here, we identified a small molecule (named Inulanolide A) that dually inhibited both NFAT1 and MDM2 in breast cancer cells in vitro and in vivo. Unlike conventional MDM2 inhibitors, Inulanolide A (InuA) exerted its selective anticancer activity in both p53-dependent and -independent manners. InuA decreased cell proliferation and induced G2/M phase arrest and apoptosis in breast cancer cells; it also led to a decrease in MDM2, NFAT1 and proteins associated with cell proliferation, and an increase in apoptotic signal related proteins. In a mouse orthotopic model, JapA suppressed tumor growth and lung metastasis without host toxicity. Thus, InuA is a novel NFAT1 and MDM2 dual targeting agent and may be a clinical candidate for breast cancer therapy. This study also validates the effectiveness of dually targeting NFAT1 and MDM2 in breast cancer.

Pathological complete response of HER2-positive breast cancer to trastuzumab and chemotherapy can be predicted by HSD17B4 methylation

Human epidermal growth factor (HER) 2-directed therapy is the standard treatment for HER2-positive breast cancer. Patients who achieved a pathological complete response (pCR) to the therapy are associated with excellent disease-free survival. However, few molecular markers are available to predict pCR. Here, we aimed to establish a DNA methylation marker to predict the response to trastuzumab and chemotherapy. A total of 67 patients were divided into screening (n = 21) and validation (n = 46) sets. Genome-wide DNA methylation analysis of the screening set identified eight genomic regions specifically methylated in patients with pCR. Among these, HSD17B4 encoding type 4 17β-hydroxysteroid dehydrogenase was most significantly differentially methylated. The differential methylation was confirmed by pyrosequencing (P = 0.03), and a cutoff value was determined. This association was successfully validated in the validation set (P < 0.001), and patients with pCR were predicted with a high specificity (79%). Multivariate analysis, including tumor stage and hormone receptor status, showed that HSD17B4 methylation was an independent predictive factor (odds ratio: 10.0, 95% confidence interval 2.54–39.50, P = 0.001). Combination with ER status and HSD17B4 methylation improved the specificity up to 91%. Identification of HER2-positive breast cancer patients who would achieve pCR only by trastuzumab and chemotherapy may lead to surgery-free treatment for this group of breast cancer patients.

DUSP4 is associated with increased resistance against anti-HER2 therapy in breast cancer

The majority of patients develop resistance against suppression of HER2-signaling mediated by trastuzumab in HER2 positive breast cancer (BC). HER2 overexpression activates multiple signaling pathways, including the mitogen-activated protein kinase (MAPK) cascade. MAPK phosphatases (MKPs) are essential regulators of MAPKs and participate in many facets of cellular regulation, including proliferation and apoptosis. We aimed to identify whether differential MKPs are associated with resistance to targeted therapy in patients previously treated with trastuzumab. Using gene chip data of 88 HER2-positive, trastuzumab treated BC patients, candidate MKPs were identified by Receiver Operator Characteristics analysis performed in R. Genes were ranked using their achieved area under the curve (AUC) values and were further restricted to markers significantly associated with worse survival. Functional significance of the two strongest predictive markers was evaluated in vitro by gene silencing in HER2 overexpressing, trastuzumab resistant BC cell lines SKTR and JIMT-1. The strongest predictive MKPs were DUSP4/MKP-2 (AUC=0.75, p=0.0096) and DUSP6/MKP-3 (AUC=0.77, p=5.29E-05). Higher expression for these correlated to worse survival (DUSP4: HR=2.05, p=0.009 and DUSP6: HR=2, p=0.0015). Silencing of DUSP4 had significant sensitization effects – viability of DUSP4 siRNA transfected, trastuzumab treated cells decreased significantly compared to scramble-siRNA transfected controls (SKTR: p=0.016; JIMT-1: p=0.016). In contrast, simultaneous treatment with DUSP6 siRNA and trastuzumab did not alter cell proliferation. Our findings suggest that DUSP4 may represent a new potential target to overcome trastuzumab resistance.

Activatable bispecific liposomes bearing fibroblast activation protein directed single chain fragment/Trastuzumab deliver encapsulated cargo into the nuclei of tumor cells and the tumor microenvironment simultaneously

Molecular targeting plays a significant role in cancer diagnosis and therapy. However, the heterogeneity of tumors is a limiting obstacle for molecular targeting. Consequently, clinically approved drug delivery systems such as liposomes still rely on passive targeting to tumors, which does not address tumor heterogeneity. In this work, we therefore designed and elucidated the potentials of activatable bispecific targeted liposomes for simultaneous detection of fibroblast activation protein (FAP) and the human epidermal growth factor receptor 2 (HER2). The bispecific liposomes were encapsulated with fluorescence-quenched concentrations of the near-infrared fluorescent dye, DY-676-COOH, making them detectable solely post processing within target cells. The liposomes were endowed with a combination of single chain antibody fragments specific for FAP and HER2 respectively, or with the FAP single chain antibody fragment in combination with Trastuzumab, which is specific for HER2. The Trastuzumab based bispecific formulation, termed Bi-FAP/Tras-IL revealed delivery of the encapsulated dye into the nuclei of HER2 expressing cancer cells and caused cell death at significantly higher rates than the free Trastuzumab. Furthermore, fluorescence imaging and live microscopy of tumor models in mice substantiated the delivery of the encapsulated cargo into the nuclei of target tumor cells and tumor stromal fibroblasts. Hence, they convey potentials to address tumor plasticity, to improve targeted cancer therapy and reduce Trastuzumab resistance in the future.

STATEMENT OF SIGNIFICANCE

This work demonstrates the design of activatable bispecific liposomes aimed to target HER2, a poor prognosis tumor marker in many tumor types, and fibroblast activation protein (FAP), a universal tumor marker overexpressed on tumor fibroblasts and pericytes of almost all solid tumors. Encapsulating liposomes with a quenched concentration of a NIRF dye which only fluoresced after cellular degradation and activation enabled reliable visualization of the destination of the cargo in cells and animal studies. Conjugating single chain antibody fragments directed to FAP, together with Trastuzumab, a humanized monoclonal antibody for HER2 resulted in the activatable bispecific liposomes. In animal models of xenografted human breast tumors, the remarkable ability of the bispecific probes to simultaneously deliver the encapsulated dye into the nuclei of target tumor cells and tumor fibroblasts could be demonstrated. Hence, the bispecific probes represent model tools with high significance to address tumor heterogeneity and manage Trastuzumab resistance in the future.

Pathologic diagnosis of breast cancer patients: evolution of the traditional clinical-pathologic paradigm toward "precision" cancer therapy

We present an updated account of breast cancer treatment and of progress toward "precision" cancer therapy; we focus on new developments in diagnostic molecular pathology and breast cancer that have emerged during the past 2 years. Increasing awareness of new prognostic and predictive methodologies, and introduction of next generation sequencing has increased understanding of both tumor biology and clinical behavior, which offers the possibility of more appropriate therapeutic choices. It remains unclear which of these testing methodologies provides the most informative and cost-effective actionable results for predictive and prognostic pathology. It is likely, however, that an integrated "step-wise" approach that uses the traditional clinical-pathologic paradigms coordinated with molecular characterization of breast tumor tissue, will offer the most comprehensive and cost-effective options for individualized, "precision" therapy for patients with breast cancer.

The First Case of HER2+ Invasive Ductal Carcinoma Arising From a Breast Hamartoma and Literature Review

Carcinomas arising from breast hamartomas are exceedingly rare. We present the first reported case of an African-American female presenting with a right breast lump and a subsequent mammogram suggestive of a hamartoma. She later underwent lumpectomy and was found to have HER2+ invasive ductal carcinoma (IDC) arising from a hamartoma. She was amenable to HER2-targeted trastuzumab, hormone therapy and adjuvant radiation but declined chemotherapy. In a review of the literature, IDC is the predominant neoplastic type found in hamartomas. The average hamartoma size at time of neoplasm diagnosis is 6.0 cm. Patients with hamartomas greater than 6.0 cm, with changes in calcification pattern; new nodules or asymmetry should be considered for additional evaluation with ultrasound, MRI and/or biopsy. HER2 status is under-reported among cases and should be evaluated in any malignancy found within hamartomas as HER-2 therapy has improved overall survival and recurrence free survival in HER2+breast cancer patients.

Survival Impact of Primary Tumor Lymph Node Status and Circulating Tumor Cells in Patients with Colorectal Liver Metastases

OBJECTIVE

The aim of this study was to analyse the survival impact of primary tumor nodal status (N0/N+) in patients with resectable colorectal liver metastases (CLM), and to determine the value of circulating and disseminated tumor cells (CTCs/DTCs) in this setting.

METHODS

In this prospective study of patients undergoing resection of CLM from 2008 to 2011, peripheral blood was analyzed for CTCs using the CellSearch System^®, and bone marrow was sampled for DTC analyses just prior to hepatic resection. The presence of one or more tumor cells was scored as CTC/DTC-positive. Following resection of the primary tumor, the lymph nodes (LNs) were examined by routine histopathological examination.

RESULTS

A total of 140 patients were included in this study; 38 patients (27.1%) were negative at the primary colorectal LN examination (N0). CTCs were detected in 12.1% of all patients; 5.3% of patients in the N0 group and 14.7% of patients in the LN-positive (N+) group (p = 0.156), with the LN-positive group (N+) consisting of both N1 and N2 patients. There was a significant difference in recurrence-free survival (RFS) when analysing the N0 group versus the N+ group (p = 0.007) and CTC-positive versus CTC-negative patients (p = 0.029). In multivariate analysis, CTC positivity was also significantly associated with impaired overall survival (OS) [p = 0.05], whereas DTC positivity was not associated with survival.

CONCLUSION

In this cohort of resectable CLM patients, 27% had primary N0 colorectal cancer. Assessment of CTC in addition to nodal status may contribute to improved classification of patients into high- and low-risk groups, which has the potential to guide and improve treatment strategies.

Genomic regulation of invasion by STAT3 in triple negative breast cancer

Breast cancer is a heterogeneous disease comprised of four molecular subtypes defined by whether the tumor-originating cells are luminal or basal epithelial cells. Breast cancers arising from the luminal mammary duct often express estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth receptor 2 (HER2). Tumors expressing ER and/or PR are treated with anti-hormonal therapies, while tumors overexpressing HER2 are targeted with monoclonal antibodies. Immunohistochemical detection of ER, PR, and HER2 receptors/proteins is a critical step in breast cancer diagnosis and guided treatment. Breast tumors that do not express these proteins are known as "triple negative breast cancer" (TNBC) and are typically basal-like. TNBCs are the most aggressive subtype, with the highest mortality rates and no targeted therapy, so there is a pressing need to identify important TNBC tumor regulators. The signal transducer and activator of transcription 3 (STAT3) transcription factor has been previously implicated as a constitutively active oncogene in TNBC. However, its direct regulatory gene targets and tumorigenic properties have not been well characterized. By integrating RNA-seq and ChIP-seq data from 2 TNBC tumors and 5 cell lines, we discovered novel gene signatures directly regulated by STAT3 that were enriched for processes involving inflammation, immunity, and invasion in TNBC. Functional analysis revealed that STAT3 has a key role regulating invasion and metastasis, a characteristic often associated with TNBC. Our findings suggest therapies targeting STAT3 may be important for preventing TNBC metastasis.

Escalating and de-escalating treatment in HER2-positive early breast cancer

The current standard adjuvant systemic treatment of early HER2-positive breast cancer consists of chemotherapy plus 12months of trastuzumab, with or without endocrine therapy. Several trials have investigated modifications of the standard treatment that are shorter and less resource-demanding (de-escalation) or regimens that aim at dual HER2 inhibition or include longer than 12months of HER2-targeted treatment (escalation). Seven randomized trials investigate shorter than 12months of trastuzumab treatment duration. The shorter durations were not statistically inferior to the 1-year duration in the 3 trials with survival results available, but 2 of the trials were small and 1 had a relatively short follow-up time of the patients at the time of reporting. The pathological complete response (pCR) rates were numerically higher in all 9 randomized trials that compared chemotherapy plus dual HER2 inhibition consisting of trastuzumab plus either lapatinib, neratinib, or pertuzumab with chemotherapy plus trastuzumab as neoadjuvant treatments, but the superiority of chemotherapy plus dual HER2-inhibition over chemotherapy plus trastuzumab remains to be demonstrated in the adjuvant setting. One year of adjuvant trastuzumab was as effective as 2years of trastuzumab in the HERA trial, and was associated with fewer side-effects. Extending 1-year adjuvant trastuzumab treatment with 1year of neratinib improved disease-free survival in the ExteNET trial, but the patient follow-up times are still short, and no overall survival benefit was reported. Several important trials are expected to report results in the near future and may modify the current standard.

Does the molecular classification of breast cancer point the way for biomarker identification in prostate cancer?

There is significant variation in clinical outcome between patients diagnosed with prostate cancer (CaP). Although useful, statistical nomograms and risk stratification tools alone do not always accurately predict an individual’s need for and response to treatment. The factors that determine this variation are not fully elucidated. In particular, cellular response to androgen ablation and subsequent paracrine/autocrine adaptation is poorly understood and despite best therapies, median survival in castrate resistant patients is only approximately 35 mo. We propose that one way of understanding this is to look for correlates in other comparable malignancies, such as breast cancer, where markers of at least 4 distinct gene clusters coding for 4 different phenotypic subtypes have been identified. These subtypes have been shown to demonstrate prognostic significance and successfully guide appropriate treatment regimens. In this paper we assess and review the evidence demonstrating parallels in the biology and treatment approach between breast and CaP, and consider the feasibility of patients with CaP being stratified into different molecular classes that could be used to complement prostate specific antigen and histological grading for clinical decision making. We show that there are significant correlations between the molecular classification of breast and CaP and explain how techniques used successfully to predict response to treatment in breast cancer can be applied to the prostate. Molecular phenotyping is possible in CaP and identification of distinct subtypes may allow personalised risk stratification way beyond that currently available.

Comparative Effectiveness of Biomarkers to Target Cancer Treatment: Modeling Implications for Survival and Costs

BACKGROUND

Biomarkers used at the time of diagnosis to tailor treatment decisions may diffuse into clinical practice before data become available on whether biomarker testing reduces cancer mortality. In the interim, quantitative estimates of the mortality impact of testing are needed to assess the value of these diagnostic biomarkers. These estimates are typically generated by customized models that are resource intensive to build and apply.

METHODS

We developed a user-friendly system of models for Cancer Translation of Comparative Effectiveness Research (CANTRANce) to model the mortality impact of cancer interventions. The Diagnostic Biomarker module of this system projects the mortality impact of testing for a diagnostic biomarker, given data on how testing affects treatment recommendations. Costs and quality-of-life outcomes may also be modeled. We applied the Diagnostic Biomarker module to 2 case studies to demonstrate its capabilities.

RESULTS

The user interface (http://www.fhcrc.org/cantrance) allows comparative effectiveness researchers to use the Diagnostic Biomarker module of CANTRANce. Our case studies indicate that the model produces estimates on par with those generated by customized models and is a strong tool for quickly generating novel projections.

LIMITATIONS

The simple structure that makes CANTRANce user-friendly also constrains the complexity with which cancer progression can be modeled. The quality of the results rests on the quality of the input data, which may pertain to small or dissimilar populations or suffer from informative censoring.

CONCLUSIONS

The Diagnostic Biomarker module of CANTRANce is a novel public resource that can provide timely insights into the expected mortality impact of testing for diagnostic biomarkers. The model projections should be useful for understanding the long-term potential of emerging diagnostic biomarkers.

Blood Genome-Wide Transcriptional Profiles of HER2 Negative Breast Cancers Patients

Tumors act systemically to sustain cancer progression, affecting the physiological processes in the host and triggering responses in the blood circulating cells. In this study, we explored blood transcriptional patterns of patients with two subtypes of HER2 negative breast cancers, with different prognosis and therapeutic outcome. Peripheral blood samples from seven healthy female donors and 29 women with breast cancer including 14 triple-negative breast cancers and 15 hormone-dependent breast cancers were evaluated by microarray. We also evaluated the stroma in primary tumors. Transcriptional analysis revealed distinct molecular signatures in the blood of HER2− breast cancer patients according to ER/PR status. Our data showed the implication of immune signaling in both breast cancer subtypes with an enrichment of these processes in the blood of TNBC patients. We observed a significant alteration of “chemokine signaling,” “IL-8 signaling,” and “communication between innate and adaptive immune cells” pathways in the blood of TNBC patients correlated with an increased inflammation and necrosis in their primary tumors. Overall, our data indicate that the presence of triple-negative breast cancer is associated with an enrichment of altered systemic immune-related pathways, suggesting that immunotherapy could possibly be synergistic to the chemotherapy, to improve the clinical outcome of these patients.

Identification of a new class of natural product MDM2 inhibitor: In vitro and in vivo anti-breast cancer activities and target validation

The MDM2 oncogene has been suggested as a molecular target for treating human cancers, including breast cancer. Most MDM2 inhibitors under development are targeting the MDM2-p53 binding, and have little or no effects on cancers without functional p53, such as advanced breast cancer. The present study was designed to develop a new class of MDM2 inhibitors that exhibit anticancer activity in MDM2-dependent and p53-independent manners. The selective MDM2 inhibitors were discovered by a computational structure-based screening, yielding a lead compound, termed JapA. We further found that JapA inhibited cell growth, decreased cell proliferation, and induced G2/M phase arrest and apoptosis in breast cancer cells through an MDM2-dependent mechanism, regardless of p53 status. It also inhibited the tumor growth and lung metastasis in breast cancer xenograft models without causing any host toxicity. Furthermore, JapA directly bound to MDM2 protein and reduced MDM2 levels in cancer cells in vitro and in vivo by promoting MDM2 protein degradation and inhibiting MDM2 transcription, which is distinct from the existing MDM2 inhibitors. In conclusion, JapA represents a new class of MDM2 inhibitor that exerts its anticancer activity through directly down-regulating MDM2, and might be developed as a novel cancer therapeutic agent.

Drugs of abuse and addiction: A slippery slope toward liver injury

Substances of abuse induce alteration in neurobehavioral symptoms, which can lead to simultaneous exacerbation of liver injury. The biochemical changes of liver are significantly observed in the abused group of people using illicit drugs or drugs that are abused. A huge amount of work has been carried out by scientists for validation experiments using animal models to assess hepatotoxicity in cases of drugs of abuse. The risk of hepatotoxicity from these psychostimulants has been determined by different research groups. Hepatotoxicity of these drugs has been recently highlighted and isolated case reports always have been documented in relation to misuse of the drugs. These drugs induce liver toxicity on acute or chronic dose dependent process, which ultimately lead to liver damage, acute fatty infiltration, cholestatic jaundice, liver granulomas, hepatitis, liver cirrhosis etc. Considering the importance of drug-induced hepatotoxicity as a major cause of liver damage, this review emphasizes on various drugs of abuse and addiction which induce hepatotoxicity along with their mechanism of liver damage in clinical aspect as well as in vitro and in vivo approach. However, the mechanisms of drug-induced hepatotoxicity is dependent on reactive metabolite formation via metabolism, modification of covalent bonding between cellular components with drug and its metabolites, reactive oxygen species generation inside and outside of hepatocytes, activation of signal transduction pathways that alter cell death or survival mechanism, and cellular mitochondrial damage, which leads to alteration in ATP generation have been notified here. Moreover, how the cytokines are modulated by these drugs has been mentioned here.

Prospective cohort study using the breast cancer spheroid model as a predictor for response to neoadjuvant therapy--the SpheroNEO study

Background

Aim of this prospective study was to predict response to neoadjuvant therapy in breast cancer patients using an in vitro breast cancer spheroid model.

Methods

Three-dimensional spheroids were directly generated from fresh breast tumor biopsies of 78 patients eligible for neoadjuvant therapy. Cell survival was measured after in vitro exposure to the equivalent therapeutic agents in the breast cancer spheroid model. Treatment results in vitro were correlated with pathological complete response (pCR, i.e. ypT0 ypN0) determined at surgery.

Results

A mean cell survival of 21.8 % was found in the breast cancer spheroid model for 22 patients with pCR versus 63.8 % in 56 patients without pCR (P = .001). The area under the receiver operator characteristic curve to predict pCR was 0.86 (95 % CI: 0.77 to 0.96) for cell survival in vitro compared to 0.80 (95 % CI: 0.70 to 0.90) for a combined model of conventional factors (hormone- and HER2 receptor, and age). A cutoff at 35 % cell survival for the spheroid model was proposed. Out of the 32 patients with values below this threshold, 21 patients (65.6 %) and one patient (2.2 %) with a cell survival greater than 35 % achieved pCR respectively; (sensitivity 95.5 % (95 % CI: 0.86 to 1.00); specificity 80.4 % (95 % CI: 0.70 to 0.91)). Extent of residual disease positively correlated with increased cell survival (P = .021).

Conclusion

The breast cancer spheroid model proved to be a highly sensitive and specific predictor for pCR after neoadjuvant chemotherapy in breast cancer patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1491-7) contains supplementary material, which is available to authorized users.

Treatment patterns among elderly patients with stage IV breast cancer treated with HER-2-targeted therapy

AIM

To evaluate treatment patterns among elderly, newly diagnosed stage IV breast cancer patients receiving HER-2-targeted therapy.

METHODS

Women aged 65+ with an incident diagnosis of stage IV breast cancer (index) and no history of other cancer were identified from 2006 to 2010 linked Surveillance, Epidemiology and End RESULTS and Medicare data. Continuous enrollment from 1 year preindex (baseline) through disenrollment, death or the end of the data (follow-up) was required. Patients were required to receive HER-2-targeted therapy (trastuzumab or lapatinib) during follow-up. Treatment therapies during follow-up were evaluated, as was the distribution of treatment combinations. Initial treatment regimens were evaluated based on the treatment(s) received after index. A 42-day gap in therapy or the addition of a biologic therapy was used as a marker for a subsequent regimen.

RESULTS

A total of 173 patients were identified (mean [standard deviation] age: 73.9 [6.7] years). The majority received trastuzumab (>93%) during follow-up (mean [standard deviation] duration: 24.3 [11.3] months), with 9.8% receiving lapatinib. Most received chemotherapy (83.2%), approximately half received surgery (55.5%), over 40% received hormonal therapy and a third received radiation (35.3%). Trastuzumab + chemotherapy was the most common initial treatment regimen (43.9%); less common therapies include trastuzumab alone (17.3%), and trastuzumab + chemotherapy + hormonal (13.3%). Among patients receiving chemotherapy, the majority received a taxane-based chemotherapy. The average treatment duration for any treatment regimen was just less than a year (44.9-52.5 weeks).

CONCLUSION

Among this population, the majority received taxane-based combination chemotherapy, consistent with National Comprehensive Cancer Network guidelines.

Trichostatin A suppresses lung adenocarcinoma development in Grg1 overexpressing transgenic mice

Trichostatin A (TSA) is a histone deacetylase inhibitor and a potential therapeutic for various malignancies. The in vivo effect of TSA, however, has not been investigated in a transgenic lung cancer model. Previously, we generated transgenic mice with overexpression of Groucho-related-gene 1 (Grg1) and these mice all developed mucinous lung adenocarcinoma. Grg1 is a transcriptional co-repressor protein, the function of which is thought to depend on HDAC activity. However, functions outside the nucleus have also been proposed. We tested the supposition that Grg1-induced tumorigenesis is HDAC-dependent by assaying the therapeutic effect of TSA in the Grg1 transgenic mouse model. We found that TSA significantly inhibited lung tumorigenesis in Grg1 transgenic mice (p < 0.01). TSA did not affect overall Grg1 protein levels, but instead reduced ErbB1 and ErbB2 expression, which are upregulated by Grg1 in the absence of TSA. We confirmed this effect in A549 cells. Furthermore, lapatinib, an inhibitor of both ErbB1 and ErbB2, effectively masked the effect of TSA on the inhibition of A549 cell proliferation and migration, suggesting TSA does work, at least in part, by downregulating ErbB receptors. We additionally found that TSA reduced the expression of VEGF and VEGFR2, but not basic FGF and FGFR1. Our findings indicate that TSA effectively inhibits Grg1-induced lung tumorigenesis through the down-regulation of ErbB1 and ErbB2, as well as reduced VEGF signaling. This suggests TSA and other HDAC inhibitors could have therapeutic value in the treatment of lung cancers with Grg1 overexpression.

Systemic targeted therapy for her2-positive early female breast cancer: a systematic review of the evidence for the 2014 Cancer Care Ontario systemic therapy guideline

BACKGROUND

This systematic review addresses the question "What is the optimal targeted therapy for female patients with early-stage human epidermal growth factor receptor 2 (her2)-positive breast cancer?"

METHODS

The medline and embase databases were searched for the period January 2008 to May 2014. The Standards and Guidelines Evidence directory of cancer guidelines and the Web sites of major guideline organizations were also searched.

RESULTS

Sixty publications relevant to the targeted therapy portion of the systematic review were identified. In four major trials (hera, National Surgical Adjuvant Breast and Bowel Project B-31, North Central Cancer Treatment Group N9831, and Breast Cancer International Research Group 006), adjuvant trastuzumab for 1 year was superior in disease-free survival (dfs) and overall survival (os) to no trastuzumab; trastuzumab showed no benefit in one trial (pacs 04). A shorter duration of trastuzumab (less than 1 year compared with 1 year) was evaluated, with mixed results for dfs: one trial showed superiority (finher), one trial could not demonstrate noninferiority (phare), another trial showed equivalent results (E 2198), and one trial is still ongoing (persephone). Longer trastuzumab duration (hera: 2 years vs. 1 year) showed no improvement in dfs or os and a higher rate of cardiac events. Newer her2-targeted agents (lapatinib, pertuzumab, T-DM1, neratinib) have been or are still being evaluated in both adjuvant and neoadjuvant trials, either by direct comparison with trastuzumab alone or combined with trastuzumab. In the neoadjuvant setting (neoaltto, GeparQuinto, Neosphere), trastuzumab alone or in combination with another anti-her2 agent (lapatinib, pertuzumab) was compared with either lapatinib or pertuzumab alone and showed superior or equivalent rates of pathologic complete response. In the adjuvant setting, lapatinib alone or in combination with trastuzumab, compared with trastuzumab alone (altto) or with placebo (teach), was not superior in dfs. The results of the completed aphinity trial, evaluating the role of dual her2 blockade with trastuzumab and pertuzumab, are highly anticipated. Ongoing trials are evaluating trastuzumab as a single agent without adjuvant chemotherapy (respect) and in patients with low her2 expression (National Surgical Adjuvant Breast and Bowel Project B-47).

CONCLUSIONS

Taking into consideration disease characteristics and patient preference, 1 year of trastuzumab should be offered to all patients with her2-positive breast cancer who are receiving adjuvant chemotherapy. Cardiac function should be regularly assessed in this patient population.

Highly sensitive detection of cancer antigen human epidermal growth factor receptor 2 using novel chicken egg yolk immunoglobulin

Human epidermal growth factor receptor 2 (HER2) is an important biomarker that plays a crucial role in therapeutic decision-making for breast cancer patients. Ensuring the accuracy and reproducibility of HER2 assays by enzyme-linked immunosorbent assay (ELISA), western blot and immunohistochemistry (IHC) requires high sensitive and specific antibodies. Immunoglobulin Y (IgY) is a kind of avian antibody usually isolated from chicken egg yolks. Generation and use of IgY is of increasing interest in a wide variety of applications within the life sciences. In this study, IgY antibodies against two different truncated proteins of the extracellular domain (ECD) of human HER2 were produced, their sensitivity and specificity were evaluated. Specific IgYs were produced by hens immunized with the ECD proteins of human HER2 in long-standing immunization response and were isolated from yolks with a purity of 90% by water dilution, salt precipitations and ultrafiltration. The anti-HER2 IgYs were analytically validated for specificity by ELISA, western blot, immunocytochemistry and IHC. The IgYs bound desired targets in cells and fixed tissues and showed high affinity to HER2. The results demonstrated the viability of detection of HER2 with IgYs and showed promise for the using of IgYs in strict clinical validation.

Impact of body mass index on neoadjuvant treatment outcome: a pooled analysis of eight prospective neoadjuvant breast cancer trials

Obesity is associated with an increased risk of breast cancer (BC) and poorer outcome. We assessed the impact of body mass index (BMI) on pathological complete response (pCR), disease-free (DFS), and overall survival (OS), according to BC subtypes in patients with primary BC treated with neoadjuvant chemotherapy. 8,872 patients with primary BC from eight neoadjuvant trials were categorized according to BMI: underweight (<18.5 kg/m(2)), normal weight (18.5 to <25 kg/m(2)), overweight (25 to <30 kg/m(2)), obese (30 to <40 kg/m(2)), and very obese (≥40 kg/m(2)). BC subtypes were defined as luminal-like (ER/PgR-positive and HER2-negative), HER2/luminal (ER/PgR-positive and HER2-positive), HER2-like (ER/PgR-negative and HER2-positive), and triple-negative (TNBC; ER/PgR- and HER2-negative). pCR rate was higher in normal weight patients compared with all other BMI groups (P = 0.003). Mean DFS and OS were shorter in obese (87.3 months, P = 0.014 and 94.9 months, P = 0.001, respectively) and very obese (66.6 months, P < 0.001 and 75.3 months, P < 0.001, respectively) compared with normal weight patients (91.5 and 98.8 months, respectively) which was confirmed by subpopulation treatment effect pattern plot analyses and was consistent in luminal-like and TNBC. No interaction was observed between BMI and pCR. Normal weight patients experienced less non-hematological adverse events (P = 0.002) and were more likely to receive full taxane doses (P < 0.001) compared with all other BMI groups. In multivariable analysis, the dose of taxanes was predictive for pCR (P < 0.001). Higher BMI was associated with lower pCR and a detrimental impact on survival. Normal weight patients had the best compliance to chemotherapy and received the highest taxane doses, which seems to be related with treatment outcomes.

Chromosomal aneuploidies and combinational fluorescence in situ hybridization probe panels are useful for predicting prognosis for esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is a common cancer type in China. In this study, we aimed to develop aneuploidy markers for diagnosis and prognosis of ESCC.

METHODS

Chromosomal aneuploidies were detected in 493 primary tumors and 61 precancerous lesions by fluorescence in situ hybridization with chromosome enumeration probes (CEP), and cut-off values were set by receiver operating characteristic (ROC) curves.

RESULTS

According to the cut-off values, chromosomes 3, 8, 10, 12, 17 and 20 presented frequent gains, with rates of 70.1, 69.7, 58.9, 66.9, 67.5 and 77.2 % in tumors and of 32.1, 26.8, 33.9, 41.2, 44.0 and 42.0 % in precancerous lesions. Loss of chromosome Y was detected in 72.0 % of male patients. An optimal four-probe panel CEP3/12/17/20 was established for detecting ESCC (sensitivity: 86.1 %), and CEP3/10/12/20 for precancerous lesions (sensitivity: 48.0 %). Gain of CEP8 was significantly correlated with lymph node metastasis (LNM) and late stages (P = 0.002 and 0.001), and loss of CEPY with age (P = 0.002, male). Kaplan-Meier survival curves indicated that patients with positive CEP10/17 (pT1 + T2, P = 0.041) and CEP8/17 (stages IIb + III + IV, P = 0.002) had poor overall survival. Combinations of LNM/stage and CEP panels could divide patients into more subgroups, including LNM + CEP3/17, LNM + CEP10/17, LNM + CEP3/10/17, stage + CEP3/17, stage + CEP10/17 and stage + CEP3/10/17 (P = 0.0004, 0.0003, 0.0001, 0.005, 0.001 and 0.0008, respectively). Multivariate Cox regression analysis confirmed that the above combinational models were independent prognostic factors.

CONCLUSIONS

Our data suggest that the combinational probe sets may have potential for detection and prognostic prediction of ESCC.