Neoadjuvant T-DM1/pertuzumab and paclitaxel/trastuzumab/pertuzumab for HER2+ breast cancer in the adaptively randomized I-SPY2 trial

Role of imaging based response assesment for adapting neoadjuvant systemic therapy for breast cancer: A systematic review

PURPOSE

The objective of this systematic review is to investigate the role of imaging in response monitoring during neoadjuvant systemic therapy (NST) for breast cancer and assess whether treatment modifications based on imaging response are implemented in clinical practice.

METHODS

A systematic review was conducted, analyzing five clinical practice guidelines and 147 clinical trial publications involving NST for breast cancer. The snowballing technique was employed, using a "start set" of clinical guidelines to trace relevant trials. Additionally, a PubMed search was conducted to identify trials published between 2023-2024. The review analyzed the use of imaging modalities, timing, and response criteria, and whether escalation, de-escalation, or change of treatment occurred based on imaging response.

RESULTS

Imaging was utilized in 81 % (119/147) of the trials, with ultrasound, MRI, and mammography being the most frequently employed modalities. Mid-treatment imaging was applied in 56 % (83/147) of the trials. However, only 15 % (22/147) of the trials implemented treatment modifications based on imaging response, highlighting the limited application of imaging response-guided therapy. No standardized imaging protocols or consistent response-guided treatment strategies were identified across the trials or clinical practice guidelines, with considerable variability in imaging methods, timing, and response criteria.

CONCLUSION

This systematic review underscores the critical need for standardized imaging protocols, response assessment criteria and image-guided treatment decisions. It is therefore evident that imaging for response monitoring during treatment should preferably be performed within clinical trials.

Multi-omic profiling in breast cancer: utility for advancing diagnostics and clinical care

INTRODUCTION

Breast cancer remains a major global health challenge. While advances in precision oncology have contributed to improvements in patient outcomes and provided a deeper understanding of the biological mechanisms that drive the disease, historically, research and patients' allocation to treatment have heavily relied on single-omic approaches, analyzing individual molecular dimensions such as genomics, transcriptomics, or proteomics. While these have provided deep insights into breast cancer biology, they often fail to offer a complete understanding of the disease's complex molecular landscape.

AREAS COVERED

In this review, the authors explore the recent advancements in multi-omic research in the realm of breast cancer and use clinical data to show how multi-omic integration can offer a more holistic understanding of the molecular alterations and their functional consequences underlying breast cancer.

EXPERT OPINION

The overall developments in multi-omic research and AI are expected to complement precision diagnostics through potentially refining prognostic models, and treatment selection. Overcoming challenges such as cost, data complexity, and lack of standardization is crucial for unlocking the full potential of multi-omics and AI in breast cancer patient care to enable the advancement of personalized treatments and improve patient outcomes.

Chemotherapy-free neoadjuvant pembrolizumab combined with trastuzumab and pertuzumab in HER2-enriched early breast cancer (WSG-KEYRICHED-1): a single-arm, phase 2 trial

BACKGROUND

Accumulating evidence indicates that about 30-40% of patients with HER2-positive early breast cancer might achieve excellent outcomes without chemotherapy. Therefore, we aimed to test the pathological complete response after the addition of pembrolizumab to dual anti-HER2 blockade and omission of chemotherapy in patients with HER2-enriched breast cancer.

METHODS

WSG-KEYRICHED-1 was a single-arm, multicentre, open-label, hypothesis-generating phase 2 trial done at 15 breast cancer centres in Germany. Women aged 18 years and older, with previously untreated clinical stage T1c-T3, N0-N2, M0, primary unilateral early invasive breast cancer, and locally confirmed HER2 immunohistochemistry score 2+ or 3+ status, and hormone receptor-positive or receptor-negative status, were enrolled. Women with centrally confirmed HER2-enriched subtype by prediction analysis of microarrays 50 gene set (PAM50) and an Eastern Cooperative Oncology Group performance status of 0-1 were allocated to four cycles of intravenous pembrolizumab (200 mg every 3 weeks for 12 weeks), intravenous trastuzumab biosimilar ABP 980 (8 mg/kg loading dose, then 6 mg/kg every 3 weeks for 12 weeks), and intravenous pertuzumab (840 mg loading dose, then 420 mg every 3 weeks for 12 weeks). The primary outcome was the proportion of patients with a pathological complete response (defined as ypN0 or ypT0/is), assessed in the full analysis set, which included all patients who had at least one dose of trial treatment and had central tumour assessment within 3 weeks after the end of trial treatment. For the primary endpoint to be met, at least 52·2% of patients had to have a pathological complete response to support the hypothesis that the proportion of patients with pathological complete response after trial treatment would be higher than 40% with statistical significance. Safety was analysed in all patients who had at least one dose of trial treatment. The study is registered with ClinicalTrials.gov, NCT03988036, and has been completed.

FINDINGS

Between Sept 2, 2020, and May 5, 2021, 48 women were enrolled, of whom four did not have surgery, and one had only a local pathological complete response assessment. Therefore, 43 patients with central pathological complete response assessment were included in the full analysis set. Median follow-up was 8·6 months (IQR 8·3-9·0). 20 (47%) of 43 patients had a pathological complete response by central assessment (lower bound of the one-sided 95% CI 33%), thus the null hypothesis (40% pathological complete response) could not be rejected (p=0·22). Four (8%) of 48 patients had grade 3-4 adverse events deemed related to drug treatment. The most common grade 3-4 adverse events were increased alanine aminotransferase (n=1), drug hypersensitivity (n=1), nephritis (n=1), and panic attack (n=1). Serious adverse events occurred in four (8%) of 48 patients, which were drug hypersensitivity (n=1), panic attack (n=1), pyrexia (n=1), and COVID-19 (n=1). Pembrolizumab was discontinued or postponed due to adverse events in three (6%) of 48 patients. No deaths occurred.

INTERPRETATION

Although the null hypothesis could not be rejected, the WSG-KEYRICHED-1 trial highlights the potential of a short chemotherapy-free combination of pembrolizumab with dual anti-HER2 therapy, warranting the initiation of randomised trials investigating the immunotherapy without chemotherapy in patients with HER2-enriched breast cancer.

FUNDING

Merck Sharp & Dohme and NanoString Technologies.

Real-time functional proteomics enhances therapeutic targeting in precision oncology molecular tumor boards

Collaborative review of molecular profiling data by multidisciplinary molecular tumor boards (MTB) is increasingly important for improving patient management and outcomes, though currently relies nearly exclusively on nucleic acid next-generation sequencing (NGS) and limited panels of immunohistochemistry-based protein abundance data. We examined the feasibility of incorporating real-time laser microdissection (LMD) enrichment of tumor epithelium and commercial CLIA-based reverse phase protein array (RPPA) protein drug target expression/activation profiling into our cancer center's MTB to complement standard clinical NGS-based profiling. The LMD-RPPA workflow was performed within a therapeutically permissive timeframe with a median dwell time of nine days, during which specimens were processed outside of standard clinical workflows. The RPPA-generated data supported additional and/or alternative therapeutic considerations for 54% of profiled patients following review by the MTB. These findings suggest that integrating proteomic/phosphoproteomic and NGS-based genomic data creates opportunities to further personalize clinical decision-making for precision oncology.

The optimal neoadjuvant treatment strategy for HR+/HER2 + breast cancer: a network meta-analysis

The efficacy of neoadjuvant therapy varies significantly with hormone receptor (HR) status for patients with human epidermal growth factor receptor 2 (HER2) positive breast cancer (BC). Despite extensive research on HER2 + BC, the optimal neoadjuvant strategy for HR+/HER2 + BC remains inconclusive. This study aimed to identify the optimal neoadjuvant regimen for HR+/HER2 + BC treatment. We conducted a systematic search for trials comparing neoadjuvant regimens for HR+/HER2 + BC and a network meta-analysis. Odds ratios for pathological complete response (pCR) and hazard ratios for event-free survival (EFS) were calculated. Treatment regimens were ranked using the surface under the cumulative ranking curve. 20 trials with 2809 patients were included. In pCR analysis, three neoadjuvant regimens sequentially ranked at the top, namely those comprising T-DM1, pertuzumab with trastuzumab, and tyrosine kinase inhibitor with trastuzumab, demonstrating significantly higher pCR rates than monotherapies. In EFS analysis, pertuzumab with trastuzumab ranked the first while T-DM1 containing regimen ranked the last. Anthracycline-free regimens showed a marginally higher pCR rate than anthracycline-containing regimens, while carboplatin-containing regimens demonstrated a numerically higher pCR rate than carboplatin-free regimens. Significant heterogeneity was observed in endocrine therapy analysis, which may be caused by different strategies for incorporating endocrine therapy. In conclusion, trastuzumab plus pertuzumab stands out as the optimal neoadjuvant HER2-targeting regimen for HR+/HER2 + BC Furthermore, anthracycline-free carboplatin-containing chemotherapy emerges as a promising combination treatment. Further investigation is required to clarify the role of endocrine therapy in HR+/HER2 + BC to guide its clinical application.

In-Breast Tumor Progression During Neoadjuvant Chemotherapy: Impact on and Factors Influencing Distant Recurrence-Free Survival

BACKGROUND

Most patients with breast cancer treated with neoadjuvant chemotherapy (NAC) experience clinical benefit, however, a small proportion progress. We aimed to characterize factors predicting in-breast tumor progression and impact on distant recurrence.

PATIENTS AND METHODS

We reviewed all patients with clinical stage I-III breast cancer treated with NAC in 2006-2021 at our institution. We compared in-breast progressive disease (PD), defined as ≥ 20% increase in tumor size, with stable disease (SD) or response. Distant recurrence-free survival (DRFS) was analyzed using the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

Of 1403 patients, 70 (5%) experienced in-breast PD, 243 (17%) SD, 560 (40%) partial response (PR), and 530 (38%) breast pathologic complete response (breast pCR, ypT0/Tis). The rate of PD varied by tumor subtype (8% in HR+/HER2-, 5% TNBC, 2% HER2+, p < 0.001). With median 48 months follow-up, the rates of DRFS were significantly different according to clinical breast response as follows: PD 56%, SD 68%, PR 82%, or breast pCR 93%, p < 0.001. In patients with PD on multivariable analysis, post-NAC grade (adjusted HR 2.9, p = 0.002) and ypT3-4 category (adjusted HR 2.4, p = 0.03) were the strongest predictors of DRFS. Combining these factors, 23% had neither, 44% had one, and 33% had both, which stratified outcome in PD with 3-year DRFS of 100%, 77%, and 30%, respectively (p < 0.001).

CONCLUSIONS

While in-breast PD during NAC is uncommon (5%), it predicts poor survival. Among patients with in-breast PD, post-NAC tumor grade and T category predict outcomes and may be useful to guide treatment escalation.

Dual HER2 inhibition: mechanisms of synergy, patient selection, and resistance

HER2-targeted therapies for patients with HER2+ breast cancer are rapidly evolving, offering a range of more complex and personalized treatment options. Currently, an array of anti-HER2 monoclonal antibodies, tyrosine kinase inhibitors and antibody-drug conjugates are administered, sometimes alongside chemotherapy or endocrine therapy, both in curative and palliative contexts. However, the heterogeneous nature of HER2+ breast cancer demands a deeper understanding of disease biology and its role in responsiveness to novel HER2-targeted agents, as well as non-HER2-targeted therapies, in order to optimize patient outcomes. In this Review, we revisit the mechanisms of action of HER2-targeted agents, examine the evidence supporting the use of dual HER2 blockade in patients with HER2-amplified tumours, and explore the role of biomarkers in guiding future treatment strategies. We also discuss potential implications for the future treatment of patients with HER2+ breast cancer.

Application and challenge of HER2DX genomic assay in HER2+ breast cancer treatment

HER2-positive breast cancer is highly aggressive, with a significant risk of recurrence and metastasis, leading to a poor prognosis. While most early-stage HER2-positive breast cancer patients benefit from combining trastuzumab monoclonal antibody with chemotherapy, the therapeutic response to various drug combinations varies across the HER2+ patient population. Therefore, predicting the prognosis and treatment response of HER2+ breast cancer patients to specific regimens is crucial for selecting appropriate precision individualized therapies. HER2DX is the first genomic tool designed to guide the treatment of HER2+ breast cancer patients. The three scores provided by HER2DX inform the entire treatment process, including predicting survival outcomes, recurrence, metastasis, and treatment responses like Pathological Complete Response Rate (pCR). It offers recommendations on follow-up intervals, treatment plans, and the duration of drug therapy. This review examines the literature and analyzes studies applying HER2DX to guide the comprehensive treatment and predict prognosis in HER2+ breast cancer patients, aiming to promote the widespread use of HER2DX in individualized treatment.

Protein biomarkers for subtyping breast cancer and implications for future research: a 2024 update

INTRODUCTION

Breast cancer subtyping is used clinically for diagnosis, prognosis, and treatment decisions. Subtypes are categorized by cell of origin, histomorphology, gene expression signatures, hormone receptor status, and/or protein levels. Categorizing breast cancer based on gene expression signatures aids in assessing a patient's recurrence risk. Protein biomarkers, on the other hand, provide functional data for selecting therapies for primary and recurrent tumors. We provide an update on protein biomarkers in breast cancer subtypes and their application in prognosis and therapy selection.

AREAS COVERED

Protein pathways in breast cancer subtypes are reviewed in the context of current protein-targeted treatment options. PubMed, Science Direct, Scopus, and Cochrane Library were searched for relevant studies between 2017 and 17 August 2024.

EXPERT OPINION

Post-translationally modified proteins and their unmodified counterparts have become clinically useful biomarkers for defining breast cancer subtypes from a therapy perspective. Tissue heterogeneity influences treatment outcomes and disease recurrence. Spatial profiling has revealed complex cellular subpopulations within the breast tumor microenvironment. Deciphering the functional relationships between and within tumor clonal cell populations will further aid in defining breast cancer subtypes and create new treatment paradigms for recurrent, drug resistant, and metastatic disease.

Unveiling Neoadjuvant Therapy: Insights and Outlooks for HER2-Positive Early Breast Cancer

OPINION STATEMENT

This perspective underscores the evolution and significance of neoadjuvant therapy in breast cancer, tracing its history and efficacy in improving outcomes. It delves into the correlation between achieving complete response and long-term survival, emphasizing the predictive value of treatment response estimation. Neoadjuvant chemotherapy in HER2-positive early breast cancer, particularly with taxanes and anti-HER2 therapies, emerges as a cornerstone, offering enhanced breast conservation rates and prognostic insights. The focus on individualized care, tailored to treatment response, underscores the need for adaptive strategies. Additionally, the article discusses the ongoing debate surrounding anthracyclines' role and the benefits of dual HER2 blockade. Ultimately, advocating for a personalized approach, guided by treatment response assessment, ensures optimal outcomes in HER2-positive breast cancer management.

Implementation of antibody-drug conjugates in HER2-positive solid cancers: Recent advances and future directions

In recent decades, there has been a surge in the approval of monoclonal antibodies for treating a wide range of hematological and solid malignancies. These antibodies exhibit exceptional precision in targeting the surface antigens of tumors, heralding a groundbreaking approach to cancer therapy. Nevertheless, monoclonal antibodies alone do not show sufficient lethality against cancerous cells compared to chemotherapy. Consequently, a new class of anti-tumor medications, known as antibody-drug conjugates (ADCs), has been developed to bridge the divide between monoclonal antibodies and cytotoxic drugs, enhancing their therapeutic potential. ADCs are chemically synthesized by binding tumor-targeting monoclonal antibodies with cytotoxic payloads through linkers that are susceptible to cleavage by intracellular proteases. They combined the accurate targeting of monoclonal antibodies with the potent efficacy of cytotoxic chemotherapy drugs while circumventing systemic toxicity and boasting superior lethality over standalone targeted drugs. The human epidermal growth factor receptor (HER) family, which encompasses HER1 (also known as EGFR), HER2, HER3, and HER4, plays a key role in regulating cellular proliferation, survival, differentiation, and migration. HER2 overexpression in various tumors is one of the most frequently targeted antigens for ADC therapy in HER2-positive cancers. HER2-directed ADCs have emerged as highly promising treatment modalities for patients with HER2-positive cancers. This review focuses on three approved anti-HER2 ADCs (T-DM1, DS-8201a, and RC48) and reviews ongoing clinical trials and failed trials based on anti-HER2 ADCs. Finally, we address the notable challenges linked to ADC development and underscore potential future avenues for tackling these hurdles.

Encapsulation and release of calcein from herceptin-conjugated eLiposomes

Achieving an optimal therapeutic level is crucial in effectively eradicating cancer cells during treatment. However, conventional chemotherapy-associated systemic administration of anticancer agents leads to many side effects. To achieve the desired control over the target site, active targeting of HER2-positive breast cancer cells can be achieved by conjugating liposomal vesicles with Human Epidermal growth factor Receptor 2 (HER2) and inducing release of the encapsulated drug using ultrasound. To further enhance the delivery efficiency, nanoemulsion droplets exhibiting responsiveness to low-frequency ultrasound are encapsulated within these lipid vesicles. In this study, we prepared four different liposomal formulations, namely pegylated liposomes, emulsion liposomes (eLiposomes), HER-conjugated liposomes, and HER-conjugated eLiposomes, each loaded with calcein and subjected to a thorough characterization process. Their sizes, phospholipid concentration, and amount of antibody conjugation were compared and analyzed. Cryogenic transmission electron microscopy was used to confirm the encapsulation of nanoemulsion droplets within the liposomes. The drug-releasing performance of Herceptin-conjugated eLiposomes was found to surpass that of other liposomal formulations with a notably higher calcein release and established it as a highly effective nanocarrier. The study showcases the efficacy of calcein-loaded and Herceptin-conjugated eLiposomes, which demonstrate rapid and efficient drug release among other liposomal formulations when subjected to ultrasound. This discovery paves the way for a more targeted, efficient, and humane approach to cancer therapy.

Quantitative proteomic analysis of HER2 protein expression in PDAC tumors

Metastatic pancreatic adenocarcinoma (PDAC) is the third leading cause of cancer-related death in the United States, with a 5-year survival rate of only 11%, necessitating identification of novel treatment paradigms. Tumor tissue specimens from patients with PDAC, breast cancer, and other solid tumor malignancies were collected and tumor cells were enriched using laser microdissection (LMD). Reverse phase protein array (RPPA) analysis was performed on enriched tumor cell lysates to quantify a 32-protein/phosphoprotein biomarker panel comprising known anticancer drug targets and/or cancer-related total and phosphorylated proteins, including HER2Total, HER2Y1248, and HER3Y1289. RPPA analysis revealed significant levels of HER2Total in PDAC patients at abundances comparable to HER2-positive (IHC 3+) and HER2-low (IHC 1+ /2+ , FISH-) breast cancer tissues, for which HER2 screening is routinely performed. These data support a critical unmet need for routine clinical evaluation of HER2 expression in PDAC patients and examination of the utility of HER2-directed antibody-drug conjugates in these patients.

Axillary Nodal Response to Neoadjuvant T-DM1 Combined with Pertuzumab in a Prospective Phase II Multi-Institution Clinical Trial

BACKGROUND

Patients with ERBB2 (HER2)-positive breast cancer experience high pathologic complete response (pCR) rates after standard neoadjuvant anti-HER2 systemic therapy. We examined axillary pathologic nodal response to neoadjuvant dual HER2-targeted therapy alone, based on breast pathologic response, in a multi-institution clinical trial.

STUDY DESIGN

Patients with HER2-positive breast cancer were enrolled to a phase II single-arm trial, which administered 6 cycles of neoadjuvant trastuzumab emtansine (T-DM1) plus pertuzumab. Rates of pathologic nodal disease (ypN) in patients who were clinically node-negative (cN0) and node-positive (cN1) were analyzed, by residual breast disease (pCR and residual cancer burden [RCB] I to III).

RESULTS

One hundred fifty-eight patients completed preoperative treatment and proceeded to surgery. Of 92 patients who were cN0, 48 (52.2%) and 10 (10.9%) experienced breast pCR and RCB I, respectively. Of these, 100% were ypN0. Of 34 with RCB II to III, 26 (76.5%) were ypN0. Of 30 patients who were cN1 with breast pCR, 100% were ypN0; of the 12 patients who were cN1 with RCB I, 66.7% were ypN0; and of the 24 patients who were cN1 with RCB II to III, 25% were ypN0. ypN0 rates were significantly different between patients who did and did not experience a pCR, in both cN0 (p = 0.002) and cN1 (p < 0.001) subgroups.

CONCLUSIONS

Patients with HER2-positive breast cancer treated with dual HER2-targeted therapy who experienced a breast pCR or RCB I response were frequently ypN0. These findings support future trials considering omission of axillary surgical staging for patients with HER2-positive breast cancer in neoadjuvant trials of active HER2-targeted regimens, particularly if they experience breast pCR or RCB I.

Rational and trial design of FASCINATE-N: a prospective, randomized, precision-based umbrella trial

Background

With our growing insight into the molecular heterogeneity and biological characteristics of breast cancer, individualized treatment is the future of cancer treatment. In this prospective Fudan University Shanghai Cancer Center Breast Cancer Precision Platform Series study - neoadjuvant therapy (FASCINATE-N) trial, we classify breast cancer patients using multiomic characteristics into different subtypes to evaluate the efficacy of precision-based targeted therapies compared to standard neoadjuvant chemotherapy.

Methods and design

The FASCINATE-N trial is a prospective, randomized, precision-based umbrella trial that plans to enroll 716 women with early breast cancer. After enrollment, patients will first be divided into three groups: hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)-, HER2+, and HR-/HER2-. The HR+/HER2- patients are further stratified using fusion and clustering of similarity network fusion (SNF) algorithm into four subtypes; HER2+ patients are divided into HR+/HER2+ and HR-/HER2+ subtypes; and HR-/HER2- patients are stratified using the Fudan University Shanghai Cancer Center classification. For the assignment of drugs to patients, Bayesian methods of adaptive randomization will be used. The primary endpoint is pathological complete response rate; secondary endpoints include 3-year invasive disease-free survival, overall response rate, and toxicities according to common terminology criteria for adverse events (CTCAE) scale version 4.0 and the ratio of patients with complete cell cycle arrest (Ki67 < 2.7%) in HR+/HER2+ breast cancer.

Discussion

The goal of our trial is to test the efficacy of our subtyping-based treatment in a neoadjuvant setting and to conduct a pilot study into the efficacy of targeted therapies within each precision-based subtype. The precision-based treatment arm can be updated with the refinement of our subtyping method, the discovery of new targets, and the development of novel targeted drugs. Our trial offers a unique opportunity to provide patients with individualized neoadjuvant therapy and test promising novel treatments that may further benefit patients.

Trial registration

ClinicalTrials.gov identifier: NCT05582499 (https://classic.clinicaltrials.gov/ct2/show/NCT05582499).

HER2 heterogeneity and treatment response-associated profiles in HER2-positive breast cancer in the NCT02326974 clinical trial

BACKGROUNDHER2-targeting therapies have great efficacy in HER2-positive breast cancer, but resistance, in part due to HER2 heterogeneity (HET), is a significant clinical challenge. We previously described that in a phase II neoadjuvant trastuzumab emtansine (T-DM1) and pertuzumab (P) clinical trial in early-stage HER2-positive breast cancer, none of the patients with HER2-HET tumors had pathologic complete response (pCR).METHODSTo investigate cellular and molecular differences among tumors according to HER2 heterogeneity and pCR, we performed RNA sequencing and ERBB2 FISH of 285 pretreatment and posttreatment tumors from 129 patients in this T-DM1+P neoadjuvant trial. A subset of cases was also subject to NanoString spatial digital profiling.RESULTSPretreatment tumors from patients with pCR had the highest level of ERBB2 mRNA and ERBB signaling. HER2 heterogeneity was associated with no pCR, basal-like features, and low ERBB2 expression yet high ERBB signaling sustained by activation of downstream pathway components. Residual tumors showed decreased HER2 protein levels and ERBB2 copy number heterogeneity and increased PI3K pathway enrichment and luminal features. HET tumors showed minimal treatment-induced transcriptomic changes compared with non-HET tumors. Immune infiltration correlated with pCR and HER2-HET status.CONCLUSIONResistance mechanisms in HET and non-HET tumors are distinct. HER2-targeting antibodies have limited efficacy in HET tumors. Our results support the stratification of patients based on HET status and the use of agents that target downstream components of the ERBB signaling pathway in patients with HET tumors.TRIAL REGISTRATIONClinicalTrials.gov NCT02326974.FUNDINGThis study was funded by Roche and the National Cancer Institute.

Protein signaling and drug target activation signatures to guide therapy prioritization: Therapeutic resistance and sensitivity in the I-SPY 2 Trial

Molecular subtyping of breast cancer is based mostly on HR/HER2 and gene expression-based immune, DNA repair deficiency, and luminal signatures. We extend this description via functional protein pathway activation mapping using pre-treatment, quantitative expression data from 139 proteins/phosphoproteins from 736 patients across 8 treatment arms of the I-SPY 2 Trial (ClinicalTrials.gov: NCT01042379). We identify predictive fit-for-purpose, mechanism-of-action-based signatures and individual predictive protein biomarker candidates by evaluating associations with pathologic complete response. Elevated levels of cyclin D1, estrogen receptor alpha, and androgen receptor S650 associate with non-response and are biomarkers for global resistance. We uncover protein/phosphoprotein-based signatures that can be utilized both for molecularly rationalized therapeutic selection and for response prediction. We introduce a dichotomous HER2 activation response predictive signature for stratifying triple-negative breast cancer patients to either HER2 or immune checkpoint therapy response as a model for how protein activation signatures provide a different lens to view the molecular landscape of breast cancer and synergize with transcriptomic-defined signatures.

Race, Gene Expression Signatures, and Clinical Outcomes of Patients With High-Risk Early Breast Cancer

Importance

There has been little consideration of genomic risk of recurrence by breast cancer subtype despite evidence of racial disparities in breast cancer outcomes.

Objective

To evaluate associations between clinical trial end points, namely pathologic complete response (pCR) and distant recurrence-free survival (DRFS), and race and examine whether gene expression signatures are associated with outcomes by race.

Design, Setting, and Participants

This retrospective cohort study used data from the Investigation of Serial Studies to Predict Your Therapeutic Response With Imaging and Molecular Analysis 2 (I-SPY 2) multicenter clinical trial of neoadjuvant chemotherapy with novel agents and combinations for patients with previously untreated stage II/III breast cancer. Analyses were conducted of associations between race and short- and long-term outcomes, overall and by receptor subtypes, and their association with 28 expression biomarkers. The trial enrolled 990 female patients between March 30, 2010, and November 5, 2016, with a primary tumor size of 2.5 cm or greater and clinical or molecular high risk based on MammaPrint or hormone receptor (HR)-negative/ERBB2 (formerly HER2 or HER2/neu)-positive subtyping across 9 arms. This data analysis was performed between June 10, 2021, and October 20, 2022.

Exposure

Race, tumor receptor subtypes, and genomic biomarker expression of early breast cancer.

Main Outcomes and Measures

The primary outcomes were pCR and DRFS assessed by race, overall, and by tumor subtype using logistic regression and Cox proportional hazards regression models. The interaction between 28 expression biomarkers and race, considering pCR and DRFS overall and within subtypes, was also evaluated.

Results

The analytic sample included 974 participants (excluding 16 self-reporting as American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander, or multiple races due to small sample sizes), including 68 Asian (7%), 120 Black (12%), and 786 White (81%) patients. Median (range) age at diagnosis was 47 (25-71) years for Asian, 49 (25-77) for Black, and 49 (23-73) years for White patients. The pCR rates were 32% (n = 22) for Asian, 30% for Black (n = 36), and 32% for White (n = 255) patients (P = .87). Black patients with HR-positive/ERBB2-negative tumors not achieving pCR had significantly worse DRFS than their White counterparts (hazard ratio, 2.28; 95% CI, 1.24-4.21; P = .01), with 5-year DRFS rates of 55% (n = 32) and 77% (n = 247), respectively. Black patients with HR-positive/ERBB2-negative tumors, compared with White patients, had higher expression of an interferon signature (mean [SD], 0.39 [0.87] and -0.10 [0.99]; P = .007) and, compared with Asian patients, had a higher mitotic score (mean [SD], 0.07 [1.08] and -0.69 [1.06]; P = .01) and lower estrogen receptor/progesterone receptor signature (mean [SD], 0.31 [0.90] and 1.08 [0.95]; P = .008). A transforming growth factor β signature had a significant association with race relative to pCR and DRFS, with a higher signature associated with lower pCR and worse DRFS outcomes among Black patients only.

Conclusions and Relevance

The findings show that women with early high-risk breast cancer who achieve pCR have similarly good outcomes regardless of race, but Black women with HR-positive/ERBB2-negative tumors without pCR may have worse DRFS than White women, highlighting the need to develop and test novel biomarker-informed therapies in diverse populations.

Antibody drug conjugates: hitting the mark in pancreatic cancer?

Pancreatic cancer is one of the most common causes of cancer-related death, and the 5-year survival rate has only improved marginally over the last decade. Late detection of the disease means that in most cases the disease has advanced locally and/or metastasized, and curative surgery is not possible. Chemotherapy is still the first-line treatment however, this has only had a modest impact in improving survival, with associated toxicities. Therefore, there is an urgent need for targeted approaches to better treat pancreatic cancer, while minimizing treatment-induced side-effects. Antibody drug conjugates (ADCs) are one treatment option that could fill this gap. Here, a monoclonal antibody is used to deliver extremely potent drugs directly to the tumor site to improve on-target killing while reducing off-target toxicity. In this paper, we review the current literature for ADC targets that have been examined in vivo for treating pancreatic cancer, summarize current and on-going clinical trials using ADCs to treat pancreatic cancer and discuss potential strategies to improve their therapeutic window.

Deep (phospho)proteomics profiling of pre- treatment needle biopsies identifies signatures of treatment resistance in HER2+ breast cancer

Patients with early-stage HER2-overexpressing breast cancer struggle with treatment resistance in 20%-40% of cases. More information is needed to predict HER2 therapy response and resistance in vivo. In this study, we perform (phospho)proteomics analysis of pre-treatment HER2+ needle biopsies of early-stage invasive breast cancer to identify molecular signatures predictive of treatment response to trastuzumab, pertuzumab, and chemotherapy. Our data show that accurate quantification of the estrogen receptor (ER) and HER2 biomarkers, combined with the assessment of associated biological features, has the potential to enable better treatment outcome prediction. In addition, we identify cellular mechanisms that potentially precondition tumors to resist therapy. We find proteins with expression changes that correlate with resistance and constitute to a strong predictive signature for treatment success in our patient cohort. Our results highlight the multifactorial nature of drug resistance in vivo and demonstrate the necessity of deep tumor profiling.

Association of HER2DX with pathological complete response and survival outcomes in HER2-positive breast cancer

BACKGROUND

The HER2DX genomic test predicts pathological complete response (pCR) and survival outcome in early-stage HER2-positive (HER2+) breast cancer. Here, we evaluated the association of HER2DX scores with (i) pCR according to hormone receptor status and various treatment regimens, and (ii) survival outcome according to pCR status.

MATERIALS AND METHODS

Seven neoadjuvant cohorts with HER2DX and clinical individual patient data were evaluated (DAPHNe, GOM-HGUGM-2018-05, CALGB-40601, ISPY-2, BiOnHER, NEOHER and PAMELA). All patients were treated with neoadjuvant trastuzumab (n = 765) in combination with pertuzumab (n = 328), lapatinib (n = 187) or without a second anti-HER2 drug (n = 250). Event-free survival (EFS) and overall survival (OS) outcomes were available in a combined series of 268 patients (i.e. NEOHER and PAMELA) with a pCR (n = 118) and without a pCR (n = 150). Cox models were adjusted to evaluate whether HER2DX can identify patients with low or high risk beyond pCR status.

RESULTS

HER2DX pCR score was significantly associated with pCR in all patients [odds ratio (OR) per 10-unit increase = 1.59, 95% confidence interval 1.43-1.77; area under the ROC curve = 0.75], with or without dual HER2 blockade. A statistically significant increase in pCR rate due to dual HER2 blockade over trastuzumab-only was observed in HER2DX pCR-high tumors treated with chemotherapy (OR = 2.36 (1.09-5.42). A statistically significant increase in pCR rate due to multi-agent chemotherapy over a single taxane was observed in HER2DX pCR-medium tumors treated with dual HER2 blockade (OR = 3.11, 1.54-6.49). The pCR rates in HER2DX pCR-low tumors were ≤30.0% regardless of treatment administered. After adjusting by pCR status, patients identified as HER2DX low-risk had better EFS (P < 0.001) and OS (P = 0.006) compared with patients with HER2DX high-risk.

CONCLUSIONS

HER2DX pCR score and risk score might help identify ideal candidates to receive neoadjuvant dual HER2 blockade in combination with a single taxane in early-stage HER2+ breast cancer.

Overcoming tumor microenvironment obstacles: Current approaches for boosting nanodrug delivery

In order to achieve targeted delivery of anticancer drugs, efficacy improvement, and side effect reduction, various types of nanoparticles are employed. However, their therapeutic effects are not ideal. This phenomenon is caused by tumor microenvironment abnormalities such as abnormal blood vessels, elevated interstitial fluid pressure, and dense extracellular matrix that affect nanoparticle penetration into the tumor's interstitium. Furthermore, nanoparticle properties including size, charge, and shape affect nanoparticle transport into tumors. This review comprehensively goes over the factors hindering nanoparticle penetration into tumors and describes methods for improving nanoparticle distribution by remodeling the tumor microenvironment and optimizing nanoparticle physicochemical properties. Finally, a critical analysis of future development of nanodrug delivery in oncology is further discussed. STATEMENT OF SIGNIFICANCE: This article reviews the factors that hinder the distribution of nanoparticles in tumors, and describes existing methods and approaches for improving the tumor accumulation from the aspects of remodeling the tumor microenvironment and optimizing the properties of nanoparticles. The description of the existing methods and approaches is followed by highlighting their advantages and disadvantages and put forward possible directions for the future researches. At last, the challenges of improving tumor accumulation in nanomedicines design were also discussed. This review will be of great interest to the broad readers who are committed to delivering nanomedicine for cancer treatment.

Computational drug repositioning for the identification of new agents to sensitize drug-resistant breast tumors across treatments and receptor subtypes

Introduction

Drug resistance is a major obstacle in cancer treatment and can involve a variety of different factors. Identifying effective therapies for drug resistant tumors is integral for improving patient outcomes.

Methods

In this study, we applied a computational drug repositioning approach to identify potential agents to sensitize primary drug resistant breast cancers. We extracted drug resistance profiles from the I-SPY 2 TRIAL, a neoadjuvant trial for early stage breast cancer, by comparing gene expression profiles of responder and non-responder patients stratified into treatments within HR/HER2 receptor subtypes, yielding 17 treatment-subtype pairs. We then used a rank-based pattern-matching strategy to identify compounds in the Connectivity Map, a database of cell line derived drug perturbation profiles, that can reverse these signatures in a breast cancer cell line. We hypothesize that reversing these drug resistance signatures will sensitize tumors to treatment and prolong survival.

Results

We found that few individual genes are shared among the drug resistance profiles of different agents. At the pathway level, however, we found enrichment of immune pathways in the responders in 8 treatments within the HR+HER2+, HR+HER2-, and HR-HER2- receptor subtypes. We also found enrichment of estrogen response pathways in the non-responders in 10 treatments primarily within the hormone receptor positive subtypes. Although most of our drug predictions are unique to treatment arms and receptor subtypes, our drug repositioning pipeline identified the estrogen receptor antagonist fulvestrant as a compound that can potentially reverse resistance across 13/17 of the treatments and receptor subtypes including HR+ and triple negative. While fulvestrant showed limited efficacy when tested in a panel of 5 paclitaxel resistant breast cancer cell lines, it did increase drug response in combination with paclitaxel in HCC-1937, a triple negative breast cancer cell line.

Conclusion

We applied a computational drug repurposing approach to identify potential agents to sensitize drug resistant breast cancers in the I-SPY 2 TRIAL. We identified fulvestrant as a potential drug hit and showed that it increased response in a paclitaxel-resistant triple negative breast cancer cell line, HCC-1937, when treated in combination with paclitaxel.

Platform trials for anaesthesia and perioperative medicine: a narrative review

Large randomised trials provide the most reliable evidence of effectiveness of new treatments in clinical practice. However, the time and resources required to complete such trials can be daunting. An overarching clinical trial platform focused on a single condition or type of surgery, aiming to compare several treatments, with an option to stop any or add in new treatment options, can provide greater efficiency. This has the potential to accelerate knowledge acquisition and identify effective, ineffective, or harmful treatments faster. The master protocol of the platform defines the study population(s) and standardised procedures. Ineffective or harmful treatments can be discarded or study drug dose modified during the life cycle of the trial. Other adaptive elements that can be modified include eligibility criteria, required sample size for any comparison(s), randomisation assignment ratio, and the addition of other promising treatment options. There are excellent opportunities for anaesthetists to establish platform trials in perioperative medicine. Platform trials are highly efficient, with the potential to provide quicker answers to important clinical questions that lead to improved patient care.

Assessment of a Genomic Assay in Patients With ERBB2-Positive Breast Cancer Following Neoadjuvant Trastuzumab-Based Chemotherapy With or Without Pertuzumab

Importance

Biomarkers to guide the use of pertuzumab in the treatment of early-stage ERBB2 (formerly HER2)-positive breast cancer beyond simple ERBB2 status are needed.

Objective

To determine if use of the HER2DX genomic assay (Reveal Genomics) in pretreatment baseline tissue samples of patients with ERBB2-positive breast cancer is associated with response to neoadjuvant trastuzumab-based chemotherapy with or without pertuzumab.

Design, Setting, and Participants

This is a retrospective diagnostic/prognostic analysis of a multicenter academic observational study in Spain performed during 2018 to 2022 (GOM-HGUGM-2018-05). In addition, a combined analysis with 2 previously reported trials of neoadjuvant cohorts with results from the assay (DAPHNe and I-SPY2) was performed. All patients had stage I to III ERBB2-positive breast cancer, signed informed consent, and had available formalin-fixed paraffin-embedded tumor specimens obtained prior to starting therapy.

Exposures

Patients received intravenous trastuzumab, 8 mg/kg, loading dose, followed by 6 mg/kg every 3 weeks in combination with intravenous docetaxel, 75 mg/m2, every 3 weeks and intravenous carboplatin area under the curve of 6 every 3 weeks for 6 cycles, or this regimen plus intravenous pertuzumab, 840 mg, loading dose, followed by an intravenous 420-mg dose every 3 weeks for 6 cycles.

Main Outcome and Measures

Association of baseline assay-reported pathologic complete response (pCR) score with pCR in the breast and axilla, as well as association of baseline assay-reported pCR score with response to pertuzumab.

Results

The assay was evaluated in 155 patients with ERBB2-positive breast cancer (mean [range] age, 50.3 [26-78] years). Clinical T1 to T2 and node-positive disease was present in 113 (72.9%) and 99 (63.9%) patients, respectively, and 105 (67.7%) tumors were hormone receptor positive. The overall pCR rate was 57.4% (95% CI, 49.2%-65.2%). The proportion of patients in the assay-reported pCR-low, pCR-medium, and pCR-high groups was 53 (34.2%), 54 (34.8%), and 48 (31.0%), respectively. In the multivariable analysis, the assay-reported pCR score (as a continuous variable from 0-100) showed a statistically significant association with pCR (odds ratio [OR] per 10-unit increase, 1.43; 95% CI, 1.22-1.70; P < .001). The pCR rates in the assay-reported pCR-high and pCR-low groups were 75.0% and 28.3%, respectively (OR, 7.85; 95% CI, 2.67-24.91; P < .001). In the combined analysis (n = 282), an increase in pCR rate due to pertuzumab was found in the assay-reported pCR-high tumors (OR, 5.36; 95% CI, 1.89-15.20; P < .001) but not in the assay-reported pCR-low tumors (OR, 0.86; 95% CI, 0.30-2.46; P = .77). A statistically significant interaction between the assay-reported pCR score and the effect of pertuzumab in pCR was observed.

Conclusions and Relevance

This diagnostic/prognostic study demonstrated that the genomic assay predicted pCR following neoadjuvant trastuzumab-based chemotherapy with or without pertuzumab. This assay could guide therapeutic decisions regarding the use of neoadjuvant pertuzumab.

Ado-tratuzumab emtansine beyond breast cancer: therapeutic role of targeting other HER2-positive cancers

Ado-trastuzumab emtansine (T-DM1) is an antibody-drug conjugate approved by the FDA in 2013 for advanced HER2-positive breast cancer treatment exhibiting promising clinical benefits. However, HER2 overexpression and gene amplification have also been reported in other cancers like gastric cancer, non-small cell lung cancer (NSCLC), and colorectal cancer. Numerous preclinical studies have also revealed the significant antitumor effect of T-DM1 on HER2-positive tumors. With the advancement in research, several clinical trials have been conducted to investigate the antitumor effect of T-DM1. In this review, we briefly introduced the pharmacological effects of T-DM1. We reviewed its preclinical and clinical studies, especially on other HER2-positive cancers, establishing what has been encountered between its preclinical and clinical studies. In clinical studies, we found that T-DM1 has a therapeutic value on other cancers. An insignificant effect was observed on gastric cancer and NSCLC, inconsistent with the preclinical studies.

Antibody-Drug Conjugate Revolution in Breast Cancer: The Road Ahead

OPINION STATEMENT

Antibody drug-conjugates (ADCs) have revolutionized the treatment of many types of cancer, including breast cancer. Recently, two new ADCs have been approved, trastuzumab deruxtecan and sacituzumab govitecan; both have demonstrated impressive improvements in overall survival, trastuzumab deruxtecan in all three subtypes of metastatic breast cancer and sacituzumab govitecan in luminal and triple negative metastatic breast cancer. These drugs are the results of significant progress and innovation in the construction of the three components of an ADC, the monoclonal antibody, the payload, and the linker, and of the discovery of new target antigens. ADC engineering has profoundly changed the paradigm of cancer treatment, on one side being effective on tumors considered inherently resistant to the payload class of drugs and on the other side demonstrating activity in tumors with very low target expression. Yet, it is likely that we are just at the beginning of a new era as the identification of new targets and the introduction of new ADC constructs and combinations will expand the field of ADC rapidly over the coming years.

Using quantitative single molecule localization microscopy to optimize multivalent HER2-targeting ligands

Introduction

The progression-free survival of patients with HER2-positive metastatic breast cancer is significantly extended by a combination of two monoclonal antibodies, trastuzumab and pertuzumab, which target independent epitopes of the extracellular domain of HER2. The improved efficacy of the combination over individual antibody therapies targeting HER2 is still being investigated, and several molecular mechanisms may be in play: the combination downregulates HER2, improves antibody-dependent cell mediated cytotoxicity, and/or affects the organization of surface-expressed antigens, which may attenuate downstream signaling.

Methods

By combining protein engineering and quantitative single molecule localization microscopy (qSMLM), here we both assessed and optimized clustering of HER2 in cultured breast cancer cells.

Results

We detected marked changes to the cellular membrane organization of HER2 when cells were treated with therapeutic antibodies. When we compared untreated samples to four treatment scenarios, we observed the following HER2 membrane features: (1) the monovalent Fab domain of trastuzumab did not significantly affect HER2 clustering; (2) individual therapy with either trastuzumab or (3) pertuzumab produced significantly higher levels of HER2 clustering; (4) a combination of trastuzumab plus pertuzumab produced the highest level of HER2 clustering. To further enhance this last effect, we created multivalent ligands using meditope technology. Treatment with a tetravalent meditope ligand combined with meditope-enabled trastuzumab resulted in pronounced HER2 clustering. Moreover, compared to pertuzumab plus trastuzumab, at early time points this meditope-based combination was more effective at inhibiting epidermal growth factor (EGF) dependent activation of several downstream protein kinases.

Discussion

Collectively, mAbs and multivalent ligands can efficiently alter the organization and activation of the HER2 receptors. We expect this approach could be used in the future to develop new therapeutics.

Landscape of neoadjuvant therapy in HER2-positive breast cancer: a systematic review and network meta-analysis

BACKGROUND

The recommended preoperative approach for HER2-positive breast cancer is unclear. We aimed to investigate the following: i) what is the optimal neoadjuvant regimen and ii) whether anthracyclines could be excluded.

METHODS

A systematic literature search in Medline, Embase and Web of Science databases was performed. Studies had to satisfy the following criteria: i) randomised controlled trials (RCTs), ii) enroled patients treated preoperatively for HER2-positive BC (breast cancer), iii) at least one treatment group received an anti-HER2 agent, iv) available information of any efficacy end-point and v) published in English. A network meta-analysis with a frequentist framework using random-effects model was used to pool direct and indirect evidence. Pathologic complete response (pCR), event-free survival (EFS) and overall survival (OS) were the efficacy end-points of interest, and selected safety end-points were also analysed.

RESULTS

A total of 11,049 patients with HER2-positive BC (46 RCTs) were included in the network meta-analysis, and 32 different regimens were evaluated. Dual anti-HER2-therapy, with pertuzumab or tyrosine kinase inhibitors, combined with chemotherapy was significantly superior to trastuzumab and chemotherapy in terms of pCR, EFS and OS. However, a higher risk of cardiotoxicity was observed with dual anti-HER2-therapy. Anthracycline-based chemotherapy was not associated with better efficacy outcomes in comparison with non-anthracycline-based chemotherapy. In anthracycline-free regimens, the addition of carboplatin presented numerically better efficacy outcomes.

CONCLUSION

Dual HER2 blockade with chemotherapy is the recommended choice as neoadjuvant therapy for HER2-positive breast cancer, preferably by omitting anthracyclines in favour of carboplatin.

Resistance to antibody-drug conjugates in breast cancer: mechanisms and solutions

Antibody-drug conjugates (ADCs) are a rapidly developing therapeutic approach in cancer treatment that has shown remarkable activity in breast cancer. Currently, there are two ADCs approved for the treatment of human epidermal growth factor receptor 2-positive breast cancer, one for triple-negative breast cancer, and multiple investigational ADCs in clinical trials. However, drug resistance has been noticed in clinical use, especially in trastuzumab emtansine. Here, the mechanisms of ADC resistance are summarized into four categories: antibody-mediated resistance, impaired drug trafficking, disrupted lysosomal function, and payload-related resistance. To overcome or prevent resistance to ADCs, innovative development strategies and combination therapy options are being investigated. Analyzing predictive biomarkers for optimal therapy selection may also help to prevent drug resistance.

AKT/mTOR signaling modulates resistance to endocrine therapy and CDK4/6 inhibition in metastatic breast cancers

Endocrine therapy (ET) in combination with CDK4/6 inhibition is routinely used as first-line treatment for HR+/HER2- metastatic breast cancer (MBC) patients. However, 30-40% of patients quickly develop disease progression. In this open-label multicenter clinical trial, we utilized a hypothesis-driven protein/phosphoprotein-based approach to identify predictive markers of response to ET plus CDK4/6 inhibition in pre-treatment tissue biopsies. Pathway-centered signaling profiles were generated from microdissected tumor epithelia and surrounding stroma/immune cells using the reverse phase protein microarray. Phosphorylation levels of the CDK4/6 downstream substrates Rb (S780) and FoxM1 (T600) were higher in patients with progressive disease (PD) compared to responders (p = 0.02). Systemic PI3K/AKT/mTOR activation in tumor epithelia and stroma/immune cells was detected in patients with PD. This activation was not explained by underpinning genomic alterations alone. As the number of FDA-approved targeted compounds increases, functional protein-based signaling analyses may become a critical component of response prediction and treatment selection for MBC patients.

Pyrotinib versus lapatinib therapy for HER2 positive metastatic breast cancer patients after first-line treatment failure: A meta-analysis and systematic review

INTRODUCTION

It is critical to select subsequent treatments for patients after the failure of trastuzumab therapy. Following the failure of standard trastuzumab therapy guidelines in the Chinese Society of Clinical Oncology, pyrotinib and capecitabine is a grade I recommended regimen for treating patients with HER2-positive metastatic breast cancer. Concurrently, in treating patients with HER2-positive metastatic breast cancer, lapatinib and capecitabine are also recommended regimens for those who have previously received taxanes, anthracyclines, and trastuzumab therapy. However, there is currently no systematic review and meta-analysis comparing pyrotinib with lapatinib among HER2+ MBC patients. Therefore, this study aims to perform a systematic review and meta-analysis and assess whether pyrotinib is superior to lapatinib in efficacy and safety.

METHODS

Relevant trials were searched in CNKI, Wanfang, VIP, PubMed, Embase, and Cochrane CENTRAL databases from inception until March 27th, 2022. The primary outcomes were PFS and OS, and the secondary outcomes were ORR and grade ≥3 AEs.

RESULTS

Five relevant studies were included in this study, including 2 RCTs and 3 retrospective cohort studies. Pyrotinib combined with chemotherapy is superior to lapatinib combined with chemotherapy among HER2+ metastatic breast cancer patients, with a significant improvement in PFS (prior trastuzumab therapy) (HR: 0.47, 95% CI: 0.39-0.57, p<0.001, I2 = 0%, FEM), PFS (trastuzumab resistance) (HR: 0.52, 95% CI: 0.39-0.68, p<0.001, I2 = 40%, FEM) and ORR (RR: 1.45, 95% CI: 1.26-1.67, p<0.001, I2 = 8%, FEM), but has higher grade ≥3 diarrhea incidence (RR: 2.68, 95% CI: 1.85-3.90, p<0.001, I2 = 44%, FEM).

CONCLUSIONS

The efficacy of pyrotinib combined with chemotherapy is superior to lapatinib combined with chemotherapy but has more safety risks.

Cardiac function in women receiving dual anti-Her2 antibodies (trastuzumab and pertuzumab) combined with chemotherapy for breast cancer

BACKGROUND

Chemotherapy regimens containing a combination of anti-Her2 antibodies are effective but can be associated with cardiac toxicity.

OBJECTIVES

We evaluate the outcome with a particular focus on the cardiac function of patients with Her2 over-expressed breast cancer receiving Chemotherapy regimens combined with Trastuzumab and Pertuzumab in routine clinical practice settings.

DESIGN AND METHODS

The initial cohort of patients who started Chemotherapy regimens in combination with Trastuzumab and Pertuzumab before September 2019 in four cancer units were reviewed retrospectively. All patients had regular measurements of left ventricular ejection fraction by Doppler ultrasound.

RESULTS

Sixty-seven patients were identified. Chemotherapy regimens in combination with Trastuzumab and Pertuzumab treatment were administered in the neoadjuvant and palliative settings in 28 (41.8%) and 39 (58.2%) patients, respectively. All patients underwent left ventricular ejection fraction assessment prior to starting Chemotherapy regimens in combination with Trastuzumab and Pertuzumab treatment and at 3 and 6 months later. Subsequently, left ventricular ejection fraction was measured at 9, 12, 15, 18, 21, and 24 months as long as patients are still receiving any of the treatment components. Compared to baseline, the mean left ventricular ejection fraction was not significantly different at any of the subsequent time points (range; decrease by 0.936% to increase by 1.087%: T-test P value not statistically significant for all comparisons). Trastuzumab and Pertuzumab administration was withheld temporarily for two patients due to clinically suspected cardiac toxicity which was excluded upon further investigations. In the neoadjuvant cohort, 82.3% of patients were relapse free at 3 years. The median progression-free survival was 20 months, and the median overall survival was 41 months in the palliative cohort.

CONCLUSION

In this cohort describing our limited initial experience, dual anti-Her2 antibodies (Trastuzumab and Pertuzumab) combined with chemotherapy is effective and not associated with significant cardiac toxicity when the left ventricular ejection fraction is measured every 3 months. This may suggest that previous concerns about cardiotoxicity may have been overemphasized. Further studies investigating less frequent left ventricular ejection fraction monitoring may be warranted.

Multiplexed In Situ Spatial Protein Profiling in the Pursuit of Precision Immuno-Oncology for Patients with Breast Cancer

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of many solid tumors. In breast cancer (BC), immunotherapy is currently approved in combination with chemotherapy, albeit only in triple-negative breast cancer. Unfortunately, most patients only derive limited benefit from ICIs, progressing either upfront or after an initial response. Therapeutics must engage with a heterogeneous network of complex stromal-cancer interactions that can fail at imposing cancer immune control in multiple domains, such as in the genomic, epigenomic, transcriptomic, proteomic, and metabolomic domains. To overcome these types of heterogeneous resistance phenotypes, several combinatorial strategies are underway. Still, they can be predicted to be effective only in the subgroups of patients in which those specific resistance mechanisms are effectively in place. As single biomarker predictive performances are necessarily suboptimal at capturing the complexity of this articulate network, precision immune-oncology calls for multi-omics tumor microenvironment profiling in order to identify unique predictive patterns and to proactively tailor combinatorial treatments. Multiplexed single-cell spatially resolved tissue analysis, through precise epitope colocalization, allows one to infer cellular functional states in view of their spatial organization. In this review, we discuss-through the lens of the cancer-immunity cycle-selected, established, and emerging markers that may be evaluated in multiplexed spatial protein panels to help identify prognostic and predictive patterns in BC.

Enhancing the therapeutic efficacy of nanoparticles for cancer treatment using versatile targeted strategies

Poor targeting of therapeutics leading to severe adverse effects on normal tissues is considered one of the obstacles in cancer therapy. To help overcome this, nanoscale drug delivery systems have provided an alternative avenue for improving the therapeutic potential of various agents and bioactive molecules through the enhanced permeability and retention (EPR) effect. Nanosystems with cancer-targeted ligands can achieve effective delivery to the tumor cells utilizing cell surface-specific receptors, the tumor vasculature and antigens with high accuracy and affinity. Additionally, stimuli-responsive nanoplatforms have also been considered as a promising and effective targeting strategy against tumors, as these nanoplatforms maintain their stealth feature under normal conditions, but upon homing in on cancerous lesions or their microenvironment, are responsive and release their cargoes. In this review, we comprehensively summarize the field of active targeting drug delivery systems and a number of stimuli-responsive release studies in the context of emerging nanoplatform development, and also discuss how this knowledge can contribute to further improvements in clinical practice.

Advances in neoadjuvant therapy for HER2-positive breast cancers: a narrative review

Background and Objective

Breast cancer (BC) is currently the most frequently diagnosed cancer and the primary cause of cancer-related death among women worldwide. Human epidermal growth factor receptor type 2 (HER2)-positive BC accounts for 14.5-15% of all BCs, with a relatively poor prognosis. Neoadjuvant therapy (NAT) has become a preferred treatment option for HER2+ BCs. With the continuous emergence of various clinical trials and new treatment concepts in BC, the NAT model has changed from chemotherapy alone to the neoadjuvant combination of anti-HER2-targeted therapy with chemotherapy, neoadjuvant endocrine therapy, and so on. Therefore, an up-to-date review is needed to inform the selection of NAT strategies for HER2+ BCs.

Methods

This review was administrated with literature from the PubMed database. Manuscripts were searched using the following keywords: "neoadjuvant" or "preoperative", "breast cancer" or "breast neoplasm", "HER2+" or "HER2-positive", titles and abstracts were screened and evaluated independently by two authors. Information relating to the efficacy and safety profile of NAT for patients with HER2+ BCs were included and analyzed qualitatively. Only English-language articles were included.

Key Content and Findings

This review discusses the neoadjuvant situation for the surgical management of HER2-positive BCs around the world. In this paper, we describe the efficacy assessment of NAT, analyze clinical effect and toxicity of chemotherapy, and targeted therapy, including monoclonal antibody, tyrosine kinase inhibitors (TKIs) and antibody-drug conjugates (ADCs), and other neoadjuvant treatments in HER2+ BC. The data shows while overall survival is the standard endpoint for efficacy, pathological complete response have been implemented more and more frequently in clinical trials for its convenience. Dual-targeted therapy plus chemotherapy exhibited favorable efficacy in most cases, meanwhile other treatment strategies such as combinations without chemotherapy or including CDK4/6 agents may be applicable in specific situation.

Conclusions

As an important part of BC treatment, NAT is lingering in the stage of continuous development, especially for patients with HER2-positive BC. The challenges we are facing today in this field are dose de-escalation without reducing efficacy and choose suitable combination of agents in clinical practice. Moreover, new biomarkers are warrant for individualize treatment.

Perioperative HER2 targeted treatment in early stage HER2-positive breast cancer

Although human epidermal growth factor receptor 2 (HER2)-positive breast cancer was associated with poor prognosis, it has been changed after the development of trastuzumab. There has been great progress in perioperative HER2-targeting treatment, and investigations of several novel drugs and their combinations are ongoing. Adjuvant trastuzumab with or without pertuzumab for 1 year in combination with concomitant chemotherapy has become a standard treatment in high-risk node-negative tumors or node-positive HER2-positive early breast cancer patients without residual disease or who have not received neoadjuvant treatment. For low-risk HER2-positive early breast cancer patients, adjuvant paclitaxel and 1-year trastuzumab are possible alternatives. For residual disease after neoadjuvant treatment, adjuvant trastuzumab emtansine (T-DM1) for 14 cycles is a standard treatment. Non-anthracycline chemotherapy with dual anti-HER2 targeting of trastuzumab and pertuzumab represents one of the preferred neoadjuvant regimens to achieve higher pathologic complete response (pCR) rates and better clinical outcomes. Further research is needed to develop and validate potential biomarkers to predict pCR, which could help escalate or de-escalate anti-HER2 therapy. Trials incorporating novel agents such as T-DM1, trastuzumab deruxtecan (T-DXd), and immune checkpoint inhibitors and trying to de-escalate treatments in neoadjuvant setting are ongoing. In the future, tailored treatments such as no adjuvant therapy, various HER2-directed therapies alone with chemotherapy, combinations of various HER2-directed therapies and chemotherapy, addition of immune checkpoint inhibitors, and omission of surgery will be individualized in HER2-positive early breast cancer patients.

Redefining breast cancer subtypes to guide treatment prioritization and maximize response: Predictive biomarkers across 10 cancer therapies

Using pre-treatment gene expression, protein/phosphoprotein, and clinical data from the I-SPY2 neoadjuvant platform trial (NCT01042379), we create alternative breast cancer subtypes incorporating tumor biology beyond clinical hormone receptor (HR) and human epidermal growth factor receptor-2 (HER2) status to better predict drug responses. We assess the predictive performance of mechanism-of-action biomarkers from ∼990 patients treated with 10 regimens targeting diverse biology. We explore >11 subtyping schemas and identify treatment-subtype pairs maximizing the pathologic complete response (pCR) rate over the population. The best performing schemas incorporate Immune, DNA repair, and HER2/Luminal phenotypes. Subsequent treatment allocation increases the overall pCR rate to 63% from 51% using HR/HER2-based treatment selection. pCR gains from reclassification and improved patient selection are highest in HR+ subsets (>15%). As new treatments are introduced, the subtyping schema determines the minimum response needed to show efficacy. This data platform provides an unprecedented resource and supports the usage of response-based subtypes to guide future treatment prioritization.

Treatment Efficacy Score - continuous residual cancer burden-based metric to compare neoadjuvant chemotherapy efficacy between randomized trial arms in breast cancer trials

BACKGROUND

Difference in pathologic complete response (pCR) rate after neoadjuvant chemotherapy does not capture the impact of treatment on down staging of residual cancer in the experimental arm. We developed a method to compare the entire distribution of residual cancer burden (RCB) values between clinical trial arms to better quantify the differences in cytotoxic efficacy of treatments.

PATIENTS AND METHODS

The Treatment Efficacy Score (TES) reflects the area between the weighted cumulative distribution functions of RCB values from two trial arms. TES is based on a modified Kolmogorov-Smirnov (KS) test with added weight function to capture the importance of high RCB values and uses the area under the difference between two distribution functions as statistical metric. The higher the TES the greater the shift to lower RCB values in the experimental arm. We developed TES from the durvalumab + olaparib arm (n=72) and corresponding controls (n=282) of the I-SPY2 trial. The 11 other experimental arms and control cohorts (n=947) were used as validation sets to assess the performance of TES. We compared TES to KS, Mann-Whitney, and Fisher's exact tests to identify trial arms with higher cytotoxic efficacy and assessed associations with trial arm level survival differences. Significance was assessed with permutation test.

RESULTS

In the validation set, TES identified arms with higher pCR rate but was more accurate to identify regimens as less effective if treatment did not reduce the frequency of high RCB values, even if pCR rate improved. The correlation between TES and survival was higher than the correlation between pCR rate difference and survival.

CONCLUSION

TES quantifies the difference between the entire distribution of pathologic responses observed in trial arms and could serve as a better early surrogate to predict trial arm level survival differences than pCR rate difference alone.

Characterization of anticancer drug resistance by reverse-phase protein array: new targets and strategies

INTRODUCTION

Drug resistance is the main barrier to achieving cancer cures with medical therapy. Cancer drug resistance occurs, in part, due to adaptation of the tumor and microenvironment to therapeutic stress at a proteomic level. Reverse-phase protein arrays (RPPA) are well suited to proteomic analysis of drug resistance due to high sample throughput, sensitive detection of phosphoproteins, and validation for a large number of critical cellular pathways.

AREAS COVERED

This review summarizes contributions of RPPA to understanding and combating drug resistance. In particular, contributions of RPPA to understanding resistance to PARP inhibitors, BRAF inhibitors, immune checkpoint inhibitors, and breast cancer investigational therapies are discussed. Articles reviewed were identified by MEDLINE, Scopus, and Cochrane search for keywords 'proteomics,' 'reverse-phase protein array,' 'drug resistance,' 'PARP inhibitor,' 'BRAF inhibitor,' 'immune checkpoint inhibitor,' and 'I-SPY' spanning October 1, 1960 - October 1, 2021.

EXPERT OPINION

Precision oncology has thus far failed to convert the armament of targeted therapies into durable responses for most patients, highlighting that genetic sequencing alone is insufficient to guide therapy selection and overcome drug resistance. Combined genomic and proteomic analyses paired with creative drug combinations and dosing strategies hold promise for maturing precision oncology into an era of improved patient outcomes.

Immune Effective Score as a Predictor of Response to Neoadjuvant Trastuzumab Therapy and a Prognostic Indicator for HER2-Positive Breast Cancer

Background: HER2-positive breast cancer (BC) is a highly aggressive phenotype. The role of the host immune features in predictive response to anti-HER2 therapies and prognosis in BC has already been suggested. We aimed to develop a predictive and prognostic model and examine its relevance to the clinical outcomes of patients with HER2-positive BC. Methods: Immune effective score (IES) was constructed using principal component analysis algorithms. A bioinformatic analysis using four independent cohorts (GSE66305, n = 88; GSE130786, n = 110; TCGA, n = 123; METABRIC, n = 236) established associations between IES and clinical outcomes. Results: Genes associated with neoadjuvant trastuzumab therapy response were enriched in pathways related to antitumor immune activities. IES was demonstrated to be a predictive biomarker to neoadjuvant trastuzumab therapy benefits (GSE66305: area under the curve (AUC) = 0.804; GSE130786: AUC = 0.704). In addition, IES was identified as an independent prognostic factor for overall survival (OS) in the TCGA cohort (p = 0.036, hazard ratio (HR): 0.66, 95% confidence interval (CI): 0.449–0.97) and METABRIC cohort (p = 0.037, HR: 0.9, 95% CI: 0.81–0.99). Conclusion: IES has a predictive value for response to neoadjuvant trastuzumab therapy and independent prognostic value for HER2-positive breast cancer.

Development and validation of the new HER2DX assay for predicting pathological response and survival outcome in early-stage HER2-positive breast cancer

Background

Both clinical and genomic data independently predict survival and treatment response in early-stage HER2-positive breast cancer. Here we present the development and validation of a new HER2DX risk score, and a new HER2DX pathological complete response (pCR) score, both based on a 27-gene expression plus clinical feature-based classifier.

Methods

HER2DX is a supervised learning algorithm incorporating tumour size, nodal staging, and 4 gene expression signatures tracking immune infiltration, tumour cell proliferation, luminal differentiation, and the expression of the HER2 amplicon, into a single score. 434 HER2-positive tumours from the Short-HER trial were used to train a prognostic risk model; 268 cases from an independent cohort were used to verify the accuracy of the HER2DX risk score. In addition, 116 cases treated with neoadjuvant anti-HER2-based chemotherapy were used to train a predictive model of pathological complete response (pCR); two independent cohorts of 91 and 67 cases were used to verify the accuracy of the HER2DX pCR likelihood score. Five publicly available independent datasets with >1,000 patients with early-stage HER2-positive disease were also analysed.

Findings

In Short-HER, HER2DX variables were associated with good risk outcomes (i.e., immune, and luminal) and poor risk outcomes (i.e., proliferation, and tumour and nodal staging). In an independent cohort, continuous HER2DX risk score was significantly associated with disease-free survival (DFS) (p=0·002); the 5-year DFS in the low-risk group was 97·4% (94·4-100·0%). For the neoadjuvant pCR predictor training cohort, HER2DX variables were associated with pCR (i.e., immune, proliferation and HER2 amplicon) and non-pCR (i.e., luminal, and tumour and nodal staging). In both independent test set cohorts, continuous HER2DX pCR likelihood score was significantly associated with pCR (p<0·0001). A weak negative correlation was found between the HER2DX risk score versus the pCR score (correlation coefficient -0·19).

Interpretation

The two HER2DX tests provide accurate estimates of the risk of recurrence, and the likelihood to achieve a pCR, in early-stage HER2-positive breast cancer.

Funding

This study received funding from Reveal Genomics, IDIBAPS and the University of Padova.

RAB5A expression is a predictive biomarker for trastuzumab emtansine in breast cancer

HER2 is a predictive biomarker for HER2-targeted therapeutics. For antibody-drug conjugates (ADCs; e.g., trastuzumab emtansine (T-DM1)), HER2 is utilized as a transport gate for cytotoxic agents into the cell. ADC biomarkers may therefore be more complex, also reflecting the intracellular drug transport. Here we report on a positive correlation between the early endosome marker RAB5A and T-DM1 sensitivity in five HER2-positive cell lines. Correlation between RAB5A expression and T-DM1 sensitivity is confirmed in breast cancer patients treated with trastuzumab emtansine/pertuzumab in the I-SPY2 trial (NCT01042379), but not in the trastuzumab/paclitaxel control arm. The clinical correlation is further verified in patients from the KAMILLA trial (NCT01702571). In conclusion, our results suggest RAB5A as a predictive biomarker for T-DM1 response and outline proteins involved in endocytic trafficking as predictive biomarkers for ADCs.