Human breast cancer: correlation of relapse and survival with amplification of the HER-2/neu oncogene

Insights into the molecular and genetic role of obesity in breast cancer pathogenesis

The epidemic of obesity is a growing concern and is one of the major risk factors for several chronic diseases, including several types of cancers. The correlation of breast cancer with obesity has been extensively studied and involves an interplay of hormonal, metabolic, and genetic factors explored in this review. Inflammation and hormone dysregulation play an important role in promoting a protumorigenic environment through adipose tissue, which is involved in energy storage and functions as an endocrine organ. As a result, various cytokines, primarily proinflammatory in nature, are released, resulting in low-grade inflammation promoting tumor growth. Additionally, obese conditions also induce imbalances in hormones, particularly estrogen and insulin, both of which drive carcinogenesis. Genetic components such as single nucleotide polymorphisms also play critical roles in modulating the correlation between obesity and breast cancer. This review provides a comprehensive overview of various mechanisms underlying obesity and breast cancer incidence and progression.

An electrochemical fluorescence dual-mode strategy for HER2-positive breast cancer cell detection

Breast cancer is one of the most prevalent malignancies worldwide, with HER2-overexpressing subtypes exhibiting increased aggressiveness and poorer prognosis. Accurate identification of HER2-positive subtypes is essential for the effective implementation of HER2-targeted therapy. In this study, an electrochemical fluorescence dual-mode strategy was developed for the high sensitive detection of HER2-positive breast cancer cells. Immunofluorescent quantum dot probes (IFQDs) with both fluorescence and enzyme catalysis were constructed. It labelled HER2 sites on the cell membrane to enable fluorescent imaging and cell counting. Furthermore, alkaline phosphatase (ALP) on the probe surface catalyzed the reduction of silver on the surface of the Au NPs@ITO electrode through enzyme-induced metallization, thereby enabling quantitative detection of the cells via stripping voltammetry. The application of two methods, namely enzyme-induced metallization and enrichment of signal species on the electrode surface, significantly enhanced the sensitivity of this analytical strategy. The self-monitoring of dual signals achieved more accurate analytical performance. The dual-mode strategy demonstrated satisfactory results in identifying breast cancer cells with varying HER2 expression levels and even in complex samples. It indicated that the electrochemical fluorescence dual-mode strategy had potential for typing and quantitative detection of cells with varying HER2 expression levels.

Human epidermal growth factor receptor 2(Her2)-targeted pH-responsive MR/NIRF bimodal imaging-mediated nano-delivery system for the diagnosis and treatment of undifferentiated thyroid cancer

Undifferentiated thyroid cancer (ATC) is highly malignant and does not respond well to sorafenib (SRF) treatment owing to the lack of specificity of SRF targeting. Drug delivery nanosystems can improve the efficiencies of drug in treating various cancer types. However, many conventional drug delivery nanosystems lack targeting and exhibit unresponsive drug release. Therefore, we developed a pH-responsive nano-targeted drug delivery systems using human serum albumin (HSA) as a carrier to generate manganese dioxide (MnO2)@HSA nanoparticles (NPs), then encapsulated SRF and the fluorescent dye indocyanine green (ICG) and finally modifyed the targeting antibody pertuzumab in the outer layer of the nano complexes, resulting in SRF/ICG/MnO2@HSA-pertuzumab (HISMP) NPs. This system targets human epidermal growth factor receptor 2 on the cell membrane surface of thyroid cancer cells and is designed to accumulate at tumor sites. Then, pH-responsive release of divalent manganese ions, ICG, and SRF enables magnetic resonance/fluorescence (MR/NIRF) dual-modality imaging and precise drug delivery for diagnostic and therapeutic integration. Various characterization analyses including transmission electron microscopy, Fourier infrared spectroscopy, and particle size analysis confirm that we successfully synthesized HISMP NPs with a diameter of 150.709 nm. The results of CCK8 cytotoxicity and apoptosis assays show that HISMP NPs exhibited high cytotoxicity and induce apoptosis in thyroid cancer cells. In vivo MR/NIRF imaging experiments confirmed that the HISMP NPs specifically aggregated at tumor sites and have good in vivo MR/NIRF imaging ability and effective anti-tumor activity. The nano-delivery system is expected to provide a theoretical foundation for the efficient ATC diagnosis and therapy.

Nomogram using bi-modal imaging for predicting low-level HER2 expression status in breast cancer

OBJECTIVE

To develop and validate a nomogram based on ultrasound and mammographic imaging features for predicting human epidermal growth factor receptor 2-low (HER2-low) expression status in breast cancer.

METHODS

Patients with HER2-negative breast cancer (n = 316) were retrospectively recruited and randomized into training (n = 221) and validation (n = 95) cohorts. Patients were categorized into HER-low and HER2-zero expression groups. Ultrasound and mammography images were collected. Univariate and multivariate analyses were used to identify independent risk factors for HER-low expression status in the training cohort. A predictive nomogram model was developed and validated in the validation cohort. The calibration, discrimination, and clinical net benefit of the nomogram model were assessed using calibration curves, receiver operating characteristic curves, and decision curve analyses, respectively. A Kaplan-Meier curve was drawn, and the log-rank test was used to compare progression-free survival of the two groups of patients.

RESULTS

A longer diameter, tumor margin that was not circumscribed in ultrasound and mammography images, posterior acoustic shadowing, and a higher maximum elasticity were independent predictors of HER2-low expression status; thus, they were incorporated into the nomogram model. The area under the receiver operating characteristic curve (AUC) of the nomogram model was 0.783 in the training cohort. The nomogram also showed good discrimination in the validation cohort (AUC = 0.810), and good calibration efficiency in both cohorts. Decision curve analysis indicated that the nomogram was clinically useful. The log-rank test result revealed a significant difference in progression-free survival. HER2-low expression correlated with improved breast cancer prognosis.

CONCLUSION

This nomogram may provide reference for selecting candidates for appropriate management.

A new strategy to HER2-specific antibody discovery through artificial intelligence-powered phage display screening based on the Trastuzumab framework

Human epidermal growth factor receptor 2 (HER2) is a recognized drug target, and it serves as a critical target for various cancer treatments, necessitating the discovery of more antibodies for therapeutic and detection purposes. Here, we have developed an innovative workflow for antibody generation through Artificial Intelligence-powered Phage Display Screening (AIPDS). This workflow integrates artificial intelligence-driven antibody CDRH3 sequence design, high-throughput DNA synthesis and phage display screening. We applied AIPDS workflow to generate promising antibodies against the human epidermal growth factor receptor 2 (HER2), offering a template for streamlined antibody generation. Seven novel antibodies stood out, demonstrating promising efficacy in various functional assays. Notably, DYHER2-02 demonstrates strong performance across all experimental tests. In summary, our study introduces a novel methodology to generate new antibody variants of an existing antibody using an AI-assisted phage display approach. These new antibody variants hold potential applications in research, diagnosis, and therapeutic applications.

Redefining Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer in the Era of Novel Antibody-Drug Conjugates

The advent of next-generation antibody-drug conjugates (ADCs), particularly trastuzumab deruxtecan (T-DXd), has transformed our understanding of human epidermal growth factor receptor 2 (HER2) targetability for breast cancer (BC) treatment. Historically categorized as HER2-positive or HER2-negative on the basis of trastuzumab eligibility, this classification has evolved significantly over the past 5 years. The DESTINY-Breast04 trial marked the entry of anti-HER2 therapies for patients with HER2-low BC, while DESTINY-Breast06 demonstrated the potential for earlier and broader use of T-DXd. The latter trial revealed that even minimal HER2 expression in tumors previously classified as HER2-0 might be clinically relevant and targetable with T-DXd. This has led to further refinement of HER2 classification, introducing the concepts of HER2-ultralow (HER2-0 with staining) and HER2-null BC (HER2-0 without staining). With these findings, most patients with metastatic BC are currently considered eligible for T-DXd. Accurately identifying candidates for these therapies has highlighted the limitations of current HER2 diagnostic practices, on the basis of immunohistochemistry (IHC)/in situ hybridization assessment. IHC assay, optimized to detect high levels of HER2 protein, faces limitations in discriminating finer variations at the lower end of the HER2 expression spectrum. This is further complicated by the heterogeneity of HER2 expression. To overcome these barriers, new approaches may be required. Quantitative methods for HER2 membrane assessment, genomic and transcriptomic evaluations of HER2, and the integration of artificial intelligence into tissue analysis hold promise and are currently under investigation. Additionally, noninvasive strategies, such as analysis of circulating tumor DNA or circulating tumor cells, may enable real-time HER2 status assessment and better patient selection for ADC. However, these techniques require rigorous validation to ensure their clinical utility. This evolving landscape underscores the need for improvement of diagnostic approaches to support the expanding role of ADCs in BC treatment.

A disease registry study to prospectively observe treatment patterns and outcomes in patients with HER2-positive unresectable LA/MBC: final results of the ESTHER study

PURPOSE

There are multiple contemporary systemic therapy options for patients with HER2-positive advanced breast cancer. However, there are few longitudinal data regarding what proportion of patients go on to receive later lines of therapy, real-world outcomes and the impact of brain metastases. We therefore conducted a prospective, multicentre non-interventional study to describe the anti-cancer treatment regimens used and clinical outcomes in patients with HER2-positive advanced breast cancer across multiple lines of therapy undergoing treatment in routine clinical care.

METHODS

Adult patients diagnosed with HER2-positive advanced breast cancer were recruited to a prospective, multicentre non-interventional study to observe treatment patterns and outcomes.

RESULTS

Three hundred and eleven patients were recruited with median age 57 years. Of those patients initiating first, second-, and third-line treatment, 72 (23.2%), 59 (41.3%), and 20 (35%), respectively had passed away without advancing on to subsequent lines of therapy. The median progression-free survival in the first line was 25.8 months and overall survival 56.7 months. Over the course of the study 107 (34.4%) of participants were diagnosed with CNS metastases. Median overall survival from diagnosis of brain metastases was 15.4 months.

CONCLUSIONS

Many patients treated in routine practice may not get to benefit from contemporary second and later line treatments, where brain metastases become increasingly common. These findings have implications for selection of optimal systemic therapy sequencing in advanced HER2-positive breast cancer.

CLINICAL TRIAL REGISTRATION

This study was approved by Nottingham Research Ethics Committee on 29th December 2014.

CLINICAL TRIAL REGISTRATION

NCT02393924.

Efficacy and safety of inetetamab plus pertuzumab and nab-paclitaxel as neoadjuvant therapy for HER2+ breast cancer: A single-arm multicenter phase II clinical trial

The combination of inetetamab and vinorelbine has demonstrated survival benefits with an acceptable toxicity profile in HER2+ metastatic breast cancer (MBC) patients. This multicenter, single-arm, phase II trial further evaluates the efficacy of inetetamab combined with pertuzumab and nab-paclitaxel as neoadjuvant therapy. Treatment-naïve patients with HER2+ early-stage or locally advanced BC received four cycles of intravenous inetetamab (8 mg/kg loading dose, then 6 mg/kg for subsequent doses), intravenous pertuzumab (840 mg loading dose, then 420 mg for subsequent doses), and weekly nab-paclitaxel (125 mg/m2). The primary endpoint was the total pathological complete response (tpCR) rate, defined as ypT0/is and ypN0, assessed by independent central review. From March 2023 to February 2024, 62 patients were enrolled, with the majority (61/62) completing 4 cycles of neoadjuvant therapy. The tpCR rate was 56.5% (95% CI: 43.3%-69.0%). Further analysis showed that patients with estrogen receptor (ER) negative tumors derived greater benefit, with a tpCR rate of 90.9%. The objective response rate was 90.3% (95% CI: 80.1%-96.4%). The most common grade 3 or higher adverse events were neutropenia (32.3%), decreased white blood cell count (19.4%), infectious pneumonia (3.2%), anemia (3.2%), and diarrhea (3.2%). No death occurred during the neoadjuvant treatment. Neoadjuvant treatment with inetetamab, in combination with pertuzumab and nab-paclitaxel, demonstrates good efficacy and tolerability, especially in ER-negative patients.

Prognostic impact of tumor-infiltrating lymphocytes in HER2+ metastatic breast cancer receiving first-line treatment

Breast cancer (BC) is a leading cause of death among women, with approximately 30% HER2-positive (HER2+). Although HER2-targeted therapies have improved outcomes for patients with HER2+ metastatic breast cancer (mBC), clinical challenges and prognostic variability remain. Tumor-infiltrating lymphocytes (TILs) have emerged as prognostic and predictive biomarkers in various tumors, including BC, but their role in HER2+ mBC is poorly understood. This multicentric retrospective cohort study evaluated the prognostic significance of TILs in 110 patients with HER2+ mBC treated with pertuzumab, trastuzumab, and taxane-based chemotherapy at two Italian institutes from June 2013 to May 2024. TILs were assessed on metastatic or primary tumor samples. High TILs levels (>5%) were independently associated with longer PFS and OS. TILs levels were higher in primary tumours than in metastases (p = 0.009), with significant variation by metastatic site. These findings underscore the potential of TILs as prognostic biomarkers in HER2+ mBC, necessitating further prospective studies.

Enrichment and Detection of HER2-Expressing Extracellular Vesicles Based on DNA Tetrahedral Nanostructures: A New Strategy for Liquid Biopsy in Breast Cancer

Extracellular vesicles (EVs) play a crucial role as important mediators of intercellular communication in the progression of tumors. The capture and analysis of tumor-derived EVs offer new possibilities for the application of cancer liquid biopsies. This study aims to construct a DNA tetrahedral nanostructure that specifically recognizes HER2 and CD63, enabling the effective enrichment and detection of HER2-expressing EVs (HEVs). We enriched HEVs from cell lines and 13 random clinical samples and validated their characteristics by dynamic light scattering, transmission electron microscopy, and Western blotting. Further, we detected HEVs levels in clinical samples. The HEVs levels in HER2-positive breast cancer patients were significantly higher than those in healthy/benign controls (mean, 4.737 vs 4.160 vs 4.144 U/μL, P < 0.0001), displaying a concentration gradient across different HER2 expression levels. This study establishes an approach for HEV detection, thus providing a new tool for the diagnosis of HER2-positive breast cancer.

The impact of carboplatin on pathologic complete response and survival based on HER2 low and HER2 zero status in triple negative breast cancer patients receiving neoadjuvant chemotherapy: a multicenter real-world analysis

BACKGROUND AND OBJECTIVES

Triple-negative breast cancer (TNBC) has a poor prognosis, and neoadjuvant chemotherapy (NACT) is the standard treatment for locally advanced TNBC. In this study, we aimed to evaluate the efficacy of adding carboplatin to NACT regarding pathological complete response (pCR) and survival in the HER2-low and HER2-zero subgroups of TNBC patients.

MATERIALS AND METHODS

The study included 269 patients from five medical oncology clinics. Patients were divided into two groups: HER2-low (n = 152, 56.5%) and HER2-zero (n = 117, 43.5%). Among HER2-zero patients, 30 (25.6%) received carboplatin, while 38 (25.0%) HER2-low patients received carboplatin. The benefit of adding carboplatin to NACT regarding pCR and survival was assessed in both HER2-zero and HER2-low groups.

RESULTS

When patients were evaluated according to HER2 status, the pCR rates were significantly higher in the HER2-zero group compared to the HER2-low group (45.2% versus 23.7%, p < 0.001). In the HER2-zero group, patients who received carboplatin had significantly higher pCR rates (63.3% versus 39.0%, p = 0.021). Similarly, in the HER2-low group, adding carboplatin significantly increased the pCR rates (36.8% versus 19.3%, p = 0.028). While carboplatin improved pCR rates in both HER2 subgroups, this benefit was not observed in patients with Grade 1 tumors, HER2 score 2-FISH negative tumors, or based on BRCA mutation status. Patients with pCR exhibited significantly prolonged DFS and OS (p = 0.002, p < 0.001, respectively).

CONCLUSIONS

Our research demonstrates that the addition of carboplatin increases pCR rates in both HER2-zero and HER2-low patient cohorts. We suggest that carboplatin should be considered as an addition to standard neoadjuvant chemotherapy for eligible TNBC patients, regardless of HER2-zero or HER2-low status, when appropriate based on individual patient factors and toxicity considerations.

Racial and Ethnic Disparities in Receipt of ERBB2-Targeted Therapy for Breast Cancer, 2010-2020

Importance

Among older women (aged ≥50 years) with ERBB2 (formerly HER2 or HER2/neu)-positive breast cancer, research has shown racial and ethnic disparities in access to ERBB2-targeted therapies, with Black women receiving treatment at lower rates than their White counterparts.

Objective

To examine racial and ethnic disparities in receipt of ERBB2-targeted therapies and changes in receipt over time.

Design, Setting, and Participants

This retrospective cohort study used Surveillance, Epidemiology, and End Results-Medicare linked data from January 1, 2010, to December 31, 2020. Beneficiaries who were diagnosed with ERBB2-positive breast cancer between 2010 and 2019, were aged 66 years or older at diagnosis, were continuously enrolled in Medicare Parts A and B in the 12 months before and after diagnosis, and had localized or regional stage disease at diagnosis were included. Data were analyzed from February through September 2024.

Exposure

Race and ethnicity defined as non-Hispanic Black or African American, Hispanic, or non-Hispanic White.

Main Outcome and Measures

The primary outcome was receipt of ERBB2-targeted therapies in the 12 months after diagnosis of ERBB2-positive breast cancer. Modified Poisson regression was used to evaluate the probability of receiving ERBB2-targeted therapy by race and ethnicity.

Results

Among 12 765 beneficiaries with ERBB2-positive breast cancer (median [IQR] age, 74 [69-80] years; 99.2% female), 8.1% were of Black, 6.9% Hispanic, and 85.0% White race and ethnicity, and 54.2% received ERBB2-targeted therapy. The overall proportion who received ERBB2-targeted therapies increased from 41.3% in 2010-2011 to 64.3% in 2018-2019. Compared with White patients, Black patients had a lower likelihood of receiving ERBB2-targeted therapies in 2010-2011 (adjusted risk ratio [ARR], 0.81; 95% confidence limit [CL], 0.68-0.97), as did Hispanic patients (ARR, 0.75; 95% CL, 0.62-0.92). Racial and ethnic disparities in receipt of ERBB2-targeted therapies narrowed over time, with no significant differences observed across racial and ethnic groups in 2018-2019 for Black patients (ARR, 0.97; 95% CL, 0.87-1.08) and Hispanic patients (ARR, 1.05; 95% CL, 0.95-1.16).

Conclusions and Relevance

These findings suggest a narrowing of racial and ethnic disparities in receipt of ERBB2-targeted therapies over time among older Medicare beneficiaries with ERBB2-positive breast cancer. Future research is needed to understand the practices that contributed to the narrowing of racial and ethnic disparities and to develop implementation strategies to effectively improve the quality and equity of breast cancer care.

Nano-enabled pharmacogenomics: revolutionizing personalized drug therapy

The combination of pharmacogenomics and nanotechnology science of pharmacogenomics into a highly advanced single entity has given birth to personalized medicine known as nano-enabled pharmacogenomics. This review article covers all aspects starting from pharmacogenomics to gene editing tools, how these have evolved or are likely to be evolved for pharmacogenomic application, and how these can be delivered using nanoparticle delivery systems. In this prior work, we explore the evolution of pharmacogenomics over the years, as well as new achievements in the field of genomic sciences, the challenges in drug creation, and application of the strategy of personalized medicine. Particular attention is paid to how nanotechnology helps avoid the problems that accompanied the development of pharmacogenomics earlier, for example, the question of drug resistance and targeted delivery. We also review the latest developments in nano-enabled pharmacogenomics, such as the coupling with other nanobio-technologies, artificial intelligence, and machine learning in pharmacogenomics, and the ethical and regulatory aspects of these developing technologies. The possible uses of nanotechnology in improving the chances of pated and treating drug-resistant cancers are exemplified by case studies together with the current clinical uses of nanotechnology. In the last section, we discuss the future trends and research prospects in this dynamically growing area, stressing the importance of further advancements and collaborations which will advance the nano-enabled pharmacogenomics to their maximum potential.

Prognostic value of HER2 expression in cervical adenocarcinoma: A retrospective cohort study

Human epidermal growth factor receptor 2 (HER2) is an important therapeutic target in various types of cancer, although the prognostic value and therapeutic potential of HER2 in cervical adenocarcinoma are still underexplored. The present study aimed to examine the association between HER2 expression levels and prognosis in cervical adenocarcinoma, offering new insights into targeted therapies for HER2-expressing cervical adenocarcinoma. A total of 179 patients with cervical cancer who received surgery were included, and HER2 status in surgical specimens of the included patients were assessed using two classification methods: Immunohistochemistry (IHC) alone and traditional combined IHC/fluorescence in situ hybridization (FISH). IHC alone was used to categorize patients into the HER2 zero expression (IHC 0) and HER2 expression (IHC 1+, 2+ and 3+) groups, while traditional combined IHC/FISH classified the HER2 expression as negative (IHC 0 and 1+ or IHC 2+/FISH-) or positive (IHC 3+ or IHC 2+/FISH+). Kaplan-Meier survival analysis and log-rank tests were used to assess the patients' survival prognosis. A Cox proportional hazards regression model was used to identify independent prognostic factors. The HER2 expression rate was 44.1% (79/179) according to IHC alone, while 5.0% (9/179) were classified as HER2-positive according to the traditional method. HER2 expression was significantly associated with advanced International Federation of Gynecology and Obstetrics stages, higher rates of lymph node metastasis, vascular or perineural invasion, elevated cancer antigen 125 levels and increased recurrence rate (P<0.05). Moreover, HER2 expression was significantly associated with shorter progression-free survival (PFS) time [51.02±2.75 vs. 56.01±2.22 months; hazard ratio (HR), 0.559; 95% confidence interval (CI), 0.313-0.998; P=0.049]. Additionally, programmed death-ligand 1 expression levels were significantly higher in HER2-expressing patients who died (P=0.039). When HER2 status was assessed using the traditional combined IHC/FISH method, HER2 positivity was significantly associated with poorer PFS time (36.44±7.85 vs. 55.17±1.78 months; HR, 0.125; 95% CI, 0.03033-0.5156; P=0.004). In conclusion, classification of HER2 status in patients with cervical adenocarcinoma using IHC alone may provide a promising method for predicting patient outcomes and optimizing therapeutic strategies to improve treatment efficacy.

Selective targeting of oncogenic hotspot mutations of the HER2 extracellular domain

Oncogenic mutations in the extracellular domain (ECD) of cell-surface receptors could serve as tumor-specific antigens that are accessible to antibody therapeutics. Such mutations have been identified in receptor tyrosine kinases including HER2. However, it is challenging to selectively target a point mutant, while sparing the wild-type protein. Here we developed antibodies selective to HER2 S310F and S310Y, the two most common oncogenic mutations in the HER2 ECD, via combinatorial library screening and structure-guided design. Cryogenic-electron microscopy structures of the HER2 S310F homodimer and an antibody bound to HER2 S310F revealed that these antibodies recognize the mutations in a manner that mimics the dimerization arm of HER2 and thus inhibit HER2 dimerization. These antibodies as T cell engagers selectively killed a HER2 S310F-driven cancer cell line in vitro, and in vivo as a xenograft. These results validate HER2 ECD mutations as actionable therapeutic targets and offer promising candidates toward clinical development.

Clinical implications of peripheral blood biomarkers in patients with advanced breast cancer treated with trastuzumab emtansine and trastuzumab deruxtecan

BACKGROUND

Development of antibody-drug conjugates, including trastuzumab emtansine (T-DM1) and trastuzumab deruxtecan (T-DXd), has improved the outcomes of patients with HER2-positive breast cancer. We compared the association between peripheral blood biomarkers and outcomes in patients with breast cancer treated with T-DM1 and T-DXd.

METHODS

Eighty-five women treated with T-DM1 (n = 40) or T-DXd (n = 45) for advanced disease were evaluated. Overall survival (OS) and OS after the end of treatment (EOT) were compared based on changes in absolute lymphocyte count (ALC) and neutrophil-to-lymphocyte ratio (NLR) between baseline and EOT.

RESULTS

In the T-DM1 group, patients with a low NLR at EOT had significantly longer OS after EOT than those with a high NLR (p = 0.007), and patients with a high ALC at EOT had longer OS after EOT (p = 0.071). In the T-DXd group, the ALC and NLR were not associated with OS. The exploratory subgroup analysis suggested that patients with high ALC at EOT had better OS after EOT (p = 0.038) in the T-DXd (HER2-low) group (n = 19), whereas ALC and NLR were not associated with the outcome in the T-DXd (HER2-positive) group (n = 26). Multivariable analysis revealed that the NLR at EOT was an independent prognostic factor for OS after EOT, after adjusting for clinicopathological factors, in the T-DM1 group (p = 0.019).

CONCLUSION

Immune status may influence treatment outcomes in the T-DM1 and T-DXd (HER2-low) groups. Conversely, in the T-DXd (HER2-positive) group, the treatment outcome was independent of immune status.

Overall survival of patients with de Novo HER2-positive metastatic breast cancer in the Netherlands from 2008 to 2017: A population-based cohort study of systemically treated patients

AIM

This study aims to determine whether real-world overall survival (OS) of patients with de Novo HER2-positive (HER2 +) metastatic breast cancer (MBC) in the Netherlands improved over time.

METHODS

Data of patients diagnosed with de Novo HER2 + MBC in 2008-2017 were retrieved from the Netherlands Cancer Registry. OS was estimated per two-year period using the Kaplan-Meier method and compared using the log-rank test for trend and the multivariable Cox proportional hazards analysis, adjusted for baseline characteristics and local therapy. First-given systemic and local therapy use was determined per two-year period.

RESULTS

Among 1458 patients included, 99 % (1452/1458) were female and 53 % (775/1458) aged 50-74 years at diagnosis. Comparing patients diagnosed with de Novo HER2 + MBC in 2008-2009 versus 2016-2017, the median OS improved from 30·9 months (95 %CI:25·0-35·4) to 57·3 months (95 %CI:46·7-68·1) (p-value for trend<0·001) (adjusted hazard rate ratio =0·49, 95 %CI:0·40-0·59). The use of any HER2-targeted therapy increased from 64 % (178/279) to 84 % (287/340), while the use of pertuzumab-based therapy increased from 0 % to 67 % (227/340) over the same period. The use of surgery remained stable over time, while radiotherapy use for both the primary tumour and metastases increased in recent years, from 16 % (44/279) and 15 % (42/279) in 2008-2009-22 % (76/340) and 26 % (88/340) in 2016-2017, respectively.

CONCLUSION

OS has doubled over ten years, for patients diagnosed with de Novo HER2 + MBC in the Netherlands between 2008 and 2017. No change in metastatic presentation was observed over time, suggesting the improved OS is most likely explained by treatment improvements.

Enhanced antibody-mediated cellular cytotoxicity of germline-like anti-HER2 antibodies through a point mutation in complementarity-determining regions

Human epidermal growth factor receptor 2 (HER2) is highly overexpressed on the surface of breast cancer cells, presenting an attractive target for therapeutic antibodies. Antibody-dependent cellular cytotoxicity (ADCC) is a central mechanism underlying the antitumor activities of anti-HER2 monoclonal antibodies. Here, we engineered Ab5, a germline-like anti-HER2 monoclonal antibody derived from a naïve human antibody library. Our aim was to enhance the ADCC properties of Ab5 by affinity maturation. Through an in silico aided mutagenesis analysis, we identified an Ab5 mutant termed Ab5m, exhibiting enhanced affinity compared with the parental Ab5. Computational modeling predicted that a crucial interacting residue, aspartic acid 31 on the complementarity-determining region 1 of the heavy chain involved in the important charged interactions with HER2 domain II. Substitution of aspartic acid with glutamic acid decreased the interaction energies, resulting in a remarkable affinity enhancement of Ab5m-scFv (KD = 0.2 nM) compared with parental Ab5-scFv (KD = 1.5 nM). This affinity maturation translated into the obvious improvement in ADCC and notable enhancement of tumor ablation in vivo, either alone or in combination with anti-B7-H3 antibodies. These findings suggest that the potential of affinity optimization as a strategy to enhance the ADCC properties of human germline antibodies.

Therapy of early breast cancer: current status and perspectives

Medical advancements in breast cancer are truly remarkable. Especially in recent years, numerous new therapeutics have been approved and surgical strategies have been de-escalated for specific patient groups. In the therapeutic setting, CDK4/6 inhibitors as oral maintenance therapy in early breast cancer and immune checkpoint inhibitors (Pembrolizumab) for triple-negative breast cancer (BC) are noteworthy. In the surgical field, prospective randomized controlled trials have currently explored the possibility to deescalate axillary surgery by omitting sentinel lymph node excision (INSEMA, SOUND). As a result, there have been significant improvements in prognosis and a reduction in surgical morbidity for patients. Many exciting trials are underway, and it remains to be seen whether antibody-drug conjugates beyond trastuzumab emtansine, will find their way into the treatment lines for early-stage BC. Furthermore, the integration of artificial intelligence in both diagnostics and treatment recommendation evaluation is a promising area with great potential.

Impact of Hormone Receptor Status and HER2 Expression on Neoadjuvant Targeted Therapy Response in HER2-Positive Breast Cancer: A Multicenter Retrospective Study

Previous studies indicate that HER2 protein expression and hormone receptor (HoR) status affect the sensitivity of HER2-positive breast cancer to neoadjuvant therapy, but it is unclear if sensitivity varies among subgroups defined by HER2 and HoR status. We examined 2 cohorts of patients, aged 18 to 80 years, with HER2-positive early breast cancer who underwent neoadjuvant therapy followed by surgery between January 1, 2009, and December 31, 2022: cohort 1 included 2648 patients, and cohort 2 had 141 patients with RNA expression data. Patients were divided into 4 groups based on immunohistochemical HER2 and HoR status: HER2(3+)/HoR-, HER2(3+)/HoR+, HER2(2+)/HoR-, and HER2(2+)/HoR+. We evaluated total pathological complete response (TpCR, defined as ypT0/is ypN0) rates, disease-free survival (DFS), and variations in PAM50 intrinsic subtypes across different subgroups. In cohort 1, HER2(3+)/HoR- had a higher TpCR rate (44.5%) than HER2(3+)/HoR+ (33.8%) (P < .001), HER2(2+)/HoR- (31.7%) (P = .013), and HER2(2+)/HoR+ (13.8%) (P < .001). DFS was similar across groups (P = .445). Trastuzumab or trastuzumab plus pertuzumab significantly improved TpCR rates and DFS in HER2(3+)/HoR- and HER2(3+)/HoR+ but not in HER2(2+)/HoR- and HER2(2+)/HoR+. Cohort 2 showed significant PAM50 subtype differences across these groups (P < .001). In conclusion, the responsiveness of HER2-positive breast cancer to neoadjuvant targeted therapy is significantly influenced by HER2 expression levels and HoR status, emphasizing the necessity of precision medicine approaches to tailor therapeutic strategies for improved clinical outcomes.

Unlocking the potential: Receptor-mediated targeted drug delivery in cancer therapy

Receptor-mediated targeted drug delivery has emerged as a pivotal strategy in cancer therapy, offering precision and specificity in combating malignant diseases while minimizing systemic toxicity. This review explores the multifaceted role of receptors in cancer biology, emphasizing their contributions to cancer progression, metastasis, and their potential as therapeutic targets. Ligand-based targeting approaches highlight the utility of small molecules, peptides, and antibodies, as well as the development of novel targeting ligands. A critical focus is placed on engineering receptor-targeted nanoparticles and advanced drug delivery systems. Innovations in dual-targeting strategies and the targeted delivery to the tumour microenvironment (TME) and metastatic niches are discussed, underscoring their potential to enhance therapeutic efficacy. Additionally, receptor-targeted imaging is reviewed for its dual role in diagnosis and real-time treatment monitoring. To address the challenges of side effects and off-target toxicity, strategies that minimize these risks while targeting overexpressed receptors in solid tumours are explored. Finally, the review outlines future directions in receptor-targeted cancer therapy, emphasizing the need for interdisciplinary research to refine these strategies further. This comprehensive analysis aims to provide a roadmap for advancing receptor-based therapeutic approaches, ultimately improving outcomes for cancer patients.

MicroRNAs as Endocrine Modulators of Breast Cancer

Breast cancer is an aggressive disease of multiple subtypes with varying phenotypic, hormonal, and clinicopathological features, offering enhanced resistance to conventional therapeutic regimens. There is an unmet need for reliable molecular biomarkers capable of detecting the malignant transformation from the early stages of the disease to enhance diagnosis and treatment outcomes. A subset of small non-coding nucleic acid molecules, micro ribonucleic acids (microRNAs/miRNAs), have emerged as promising biomarkers due to their role in gene regulation and cancer pathogenesis. This review discusses, in detail, the different origins and hormone-like regulatory functionalities of miRNAs localized in tumor tissue and in the circulation, as well as their inherent stability and turnover that determines the utility of miRNAs as biomarkers for disease detection, monitoring, prognosis, and therapeutic targets.

HER2 testing: evolution and update for a companion diagnostic assay

Human epidermal growth factor receptor 2 (HER2; encoded by ERBB2) testing has been a cornerstone of patient selection for HER2-targeted therapies, principally in breast cancer but also in several other solid tumours. Since the introduction of HercepTest as the original companion diagnostic for trastuzumab, HER2 assessment methods have evolved substantially, incorporating various testing modalities, from western blots, immunohistochemistry and fluorescence in situ hybridization, to early chromogenic quantitative methods and, probably in the future, fully quantitative methods. The advent of highly effective HER2-targeted antibody-drug conjugates with clinical activity at low levels of HER2 expression, such as trastuzumab deruxtecan, has necessitated the re-evaluation of HER2 testing, particularly for HER2-low tumours. In this Review, we provide an in-depth overview of the evolution of HER2 testing, the current clinical guidelines for HER2 testing across various solid tumours, challenges associated with current testing methodologies and the emerging potential of quantitative techniques. We discuss the importance of accurately defining HER2-low expression for therapeutic decision-making and how newer diagnostic approaches, such as quantitative immunofluorescence and RNA-based assays, might address the limitations of traditional immunohistochemistry-based methods. As the use of HER2-targeted therapies continues to expand to a wider range of tumour types, ensuring the precision and accuracy of HER2 testing will be crucial for guiding treatment strategies and improving patient outcomes.

Updated efficacy and safety of HLX02 versus reference trastuzumab in metastatic HER2-positive breast cancer: A randomized phase III equivalence trial

AIM

Equivalence between HLX02 and trastuzumab sourced from the European Union (EU-trastuzumab), in combination with docetaxel, was demonstrated in a phase III study. This study aimed to evaluate the long-term efficacy and safety data after 3 years of follow-up.

METHODS

Patients with previously untreated, HER2-positive metastatic breast cancer received intravenous HLX02 or EU-trastuzumab (initial dose of 8 mg/kg, followed by 6 mg/kg every 3 weeks for up to 12 months) in combination with docetaxel. Primary endpoint was the overall response rate up to week 24 (ORR24). Secondary endpoints including updated overall survival (OS), progression-free survival (PFS), safety and immunogenicity are reported in this long-term follow-up analysis.

RESULTS

After a median follow-up duration of 35.0 months, 270 out of the 649 enrolled patients had died; 128 (39.5 %) in the HLX02 and 142 (43.7 %) in the EU-trastuzumab group. Median OS was 37.3 (95 % CI 36.2, not evaluable [NE]) months and not reached (95 % CI 34.2, NE) (stratified HR 0.86 [95 % CI 0.68, 1.10]; p = 0.229), with a 3-year OS rate of 57.5 % and 54.0 %, respectively. Median PFS at this long-term follow-up assessment was 11.7 (95 % CI 11.5, 12.1) months for the HLX02 group and 10.6 (95 % CI 9.5, 11.7) months for the EU-trastuzumab group (stratified HR 0.86 [95 % CI 0.69, 1.06]; p = 0.158). No new safety concerns were reported until the end of the survival follow-up.

CONCLUSION

Long-term efficacy and safety were consistent with the previous findings. No clinically meaningful differences between HLX02 and reference trastuzumab were demonstrated.

CLINICAL TRIAL REGISTRATION

Chinadrugtrials.org CTR20160526 (September 12, 2016), ClinicalTrials.gov NCT03084237 (March 20, 2017), EudraCT 2016-000206-10 (April 27, 2017).

Comparison of the prognostic effect of pyrotinib plus trastuzumab and chemotherapy different lines therapy in HER2-positive advanced breast cancer

This study aimed to compare the efficacy of pyrotinib, trastuzumab combined with chemotherapy with different lines therapy in human epidermal growth factor receptor 2- (HER2-) positive advanced breast cancer (ABC) and analyze the factors affecting the prognosis. A total of 84 patients with median age of 49 year-old. The mPFS of patients receiving first-line pyrotinib plus trastuzumab and chemotherapy was the longest (11 months) compared with second- and third line patients (p = 0.106). The objective response rate (ORR) and disease control rate (DCR) of the total population were 33.3% and 82.1% respectively. Subgroup analysis suggested that using pyrotinib plus trastuzumab and Albumin-bound paclitaxel was not inferior to combine with Vinorelbine in regards of PFS. Histological grade (OR: 0.233[0.069 ∼ 0.781], p = 0.018) and tumor location (OR: 0.286[0.087 ∼ 0.942], p = 0.040) were independent factors influencing the ORR. Multivariate cox analysis showed that Ki-67 was independently associated with increased risk of progression (HR: 1.843[1.044-3.254], p = 0.035). The most common adverse events were diarrhea (17.9%) and neutropenia (11.9%). In the first-, second- and third-line treatment, pyrotinib plus trastuzumab and chemotherapy is effective and safe. Pyrotinib and trastuzumab combined with Albumin-bound paclitaxel may be a potential ideal treatment plan for HER2-positive advanced breast cancer.

Human Epidermal Growth Factor Receptor 2 Loss following Treatment with Trastuzumab Deruxtecan in Patients with Metastatic Breast Cancer

PURPOSE

Trastuzumab deruxtecan (T-DXd) is currently approved for treating metastatic breast cancer (MBC) that is HER2 positive [immunohistochemistry (IHC) score of 3+ or in situ hybridization (ISH) positivity] or HER2-low (IHC score of 1+ or IHC 2+/ISH negative), as well as for HER2-positive gastric cancer, HER2-mutant lung cancer, and HER2-overexpressing solid tumors. Given the increasing utilization of T-DXd, we sought to determine how HER2 status might change following T-DXd therapy.

EXPERIMENTAL DESIGN

We retrospectively reviewed patients with MBC who received T-DXd at the University of Texas MD Anderson Cancer Center. We included patients with paired pre- and post-treatment biopsies assessed for HER2 status using IHC.

RESULTS

We included 41 patients with MBC who received treatment with T-DXd and had paired pre- and post-treatment biopsies assessed for HER2 status using IHC. HER2 loss was observed in 11 patients [32.4% of 34 patients with pre-treatment HER2 expression (1+, 2+, or 3+)] following treatment with T-DXd. In addition to the 11 patients with HER2 loss, another 10 patients (29.4%) had a decrease in HER2 score after treatment with T-DXd.

CONCLUSIONS

HER2 loss and decrease in HER2 expression are common in patients with MBC receiving treatment with T-DXd. Reevaluation of HER2 status following T-DXd treatment should be considered prior to alternate HER2-targeted therapies that require HER2 overexpression for efficacy.

Molecular Subtypes and Ki-67 index in Breast Carcinoma with Special Emphasis on Triple Negative Breast Cancer. A 3-year Study in a Tertiary Care Center

Purpose

Molecular subtyping of breast carcinoma and Ki-67 index has gained prominence in the recent past, as conventional factors such as surgical margins, tumor size, grade and lymph node involvement, are not sufficient to assess prognosis and make better therapeutic decisions. These subtypes include Luminal A, Luminal B, Triple Negative breast cancer (TNBC), and HER2-enriched subtypes. This study aimed to analyze the molecular subtypes and Ki-67 index in prognosis of breast carcinoma.

Method

This retrospective study was conducted in the department of Pathology in a tertiary care center over a period of 3 years. All invasive breast carcinomas (IDC) which were molecularly subtyped and Ki-67 indexed were included in the study. Statistical analysis was done using SPSS software.

Results and Discussion

Out of 253 cases, 231 cases (91.3%) were IDC-NST and 22 cases (8.7%) were special types. Metaplastic and papillary tumors were associated with higher grade and high Ki-67 value. TNBC (35.2%) showing a majority of high-grade tumors, was the most prevalent subtype followed by Luminal A (32%) showing low grade, unlike other studies which showed luminal A to be most common subtype. The rare PR positive subtype was also observed in our study.

Conclusion

TNBC and HER 2-positive subtypes exhibited bad prognosis with higher histological grade, high Ki-67 index and higher age at presentation whereas Luminal A subtype, with lower grade and low Ki-67 index showed better prognosis. Thus, this vast array of predictive and prognostic information obtained by molecular subtyping will help clinicians in not only distinguishing between low-risk and high-risk subtypes but also in customization of the treatment and follow-up of the patients.

Impact of loss of HER2 positivity following neoadjuvant therapy in HER2-positive breast cancer patients on long-term prognosis: A systematic review and meta-analysis

AIMS

The primary objective was to assess the impact of HER2 loss after neoadjuvant therapy on the long-term prognosis of patients with HER2-positive breast cancer.

METHODS

We extracted relevant studies from PubMed and Cochrane Library and performed systematic review and meta-analysis. The key eligibility criteria for the studies were as follows: included HER2-positive early breast cancer cases undergoing neoadjuvant therapy, available data on HER2 status before and after neoadjuvant therapy, and reported recurrence-related outcomes (disease-free survival/invasive disease-free survival/relapse-free survival) or overall survival.

RESULTS

Of 915 studies that were initially identified, 8 met the eligibility criteria and were included in the meta-analysis for the recurrence-related outcomes (1,917 patients with HER2 loss: 411 [21.4 %] or HER2 retained: 1,506 [78.6 %]); 4 of them reported data on overall survival (606 patients with HER2 loss: 243 [40.1 %] or HER2 retained: 363 [59.9 %]). The average follow-up duration, based on data from five out of eight studies that reported this information, was 51.6 months. HER2 loss was significantly associated with worse recurrence-related outcomes (hazards ratio [HR] 1.85, 95 % confidence interval [CI] 1.31-2.61, p = 0.0005) and worse overall survival (HR 2.37, 95 % CI 1.27-4.41, p = 0.0065). No heterogeneity or publication bias was observed in the meta-analysis.

CONCLUSIONS

This study demonstrated that compared with patients with HER2 retained, those with HER2 loss had significantly higher risk of disease recurrence and worse prognosis. These findings implied the possible use of HER2 loss as a prognostic factor in patients with HER2-positive early breast cancer. Reassessment of HER2 status after neoadjuvant therapy could be valuable in predicting prognosis and may lead to reconsideration of the rational subsequent treatment.

Pharmacology and pharmacokinetics of antibody-drug conjugates, where do we stand?

Antibody-drug conjugates (ADCs) are a rising therapeutic class in oncology and hematology, with eleven drugs approved by the US Food and Drug Administration as of January 2025. These "magic bullets" have a complex structure, including a monoclonal antibody, a linker, attachment sites, and a payload usually disrupting microtubules, targeting DNA, or inhibiting topoisomerase 1. By targeting specific tumor antigens, they are expected to be exquisitely effective in releasing "supertoxic" payloads inside tumor cells after intracellular trafficking. Additionally, they may exert a bystander effect, wherein the released payloads act on neighboring cells, amplifying their therapeutic impact regardless of target expression. ADCs have been game-changing drugs to treat tumors with once dismal prognoses or with previously considered unactionable targets, such as HER2-low or triple-negative breast cancer. To what extent there is room for personalized medicine to improve the toxicity/efficacy ratio remains unknown. However, there are inherent issues related to the complexity of the pharmacokinetics of ADCs and their assessments: efficacy or toxicity may be influenced by the clearance of the intact ADC, the circulating payload, or the payload-linker complex. Deciphering these multifaceted exposure-outcomes relationships for both efficacy and safety endpoints, is critical for advancing precision medicine and enabling personalized dosing strategies. To improve future developments and broaden their therapeutic scope, several strategies can be developed, including developing adequate combinations with other treatment classes (cytotoxic agents, immune-checkpoint inhibitors, oral molecular-targeted therapies). In this review, we will discuss the PK/PD aspects of ADCs and their dosing to improve their use in current and future indications.

CRISPR screens with trastuzumab emtansine in HER2-positive breast cancer cell lines reveal new insights into drug resistance

BACKGROUND

Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate that is an effective therapy for HER2-positive breast cancer; however, its efficacy is limited by drug resistance. While multiple mechanisms of resistance have been proposed, these are not yet well understood. Greater understanding of T-DM1 sensitivity and resistance could provide new combination strategies to overcome resistance or predictive biomarkers to guide therapy.

METHODS

We have conducted CRISPR/Cas9 functional genomics modifier screens in HER2-positive breast cancer cell lines to allow for unbiased discovery of T-DM1 sensitivity and resistance genes. Whole-genome knockout screens were carried out in MDA-MB-361 and MDA-MB-453 cells treated with T-DM1 and its payload cytotoxin DM1. Hits were validated in secondary T-DM1 screens using a focused single-guide RNA (sgRNA) library and subsequently by individual gene knockout.

RESULTS

The whole-genome CRISPR screens with T-DM1 and DM1 identified 599 genes as potential modifiers of T-DM1 sensitivity and resistance. Of these, 17 genes were significantly enriched and 3 genes depleted at P < 0.001 in either or both MDA-MB-361 and MDA-MB-453 libraries in the secondary screens. Among the top hits, were known T-DM1 sensitivity genes ERBB2 and SLC46A3, in addition to negative regulators of mTOR complex 1: TSC1 and TSC2. MDA-MB-453 clones with knockout of TSC1 or partial knockout of TSC2 were more resistant to T-DM1 than wild type cells in competition growth assays and to T-DM1 and other HER2 targeting therapies (T-DXd, lapatinib and neratinib) in growth inhibition assays, and had increased internalisation of T-DM1 at 6 h. T-DM1 and the mTOR inhibitor everolimus demonstrated synergistic activity at inhibiting cell proliferation at multiple T-DM1 concentrations across four HER2-positive breast cancer cell lines.

CONCLUSIONS

Our CRISPR screening approach with T-DM1 in HER2-positive breast cancer cell lines identified genes not previously implicated in T-DM1 sensitivity or resistance, including TSC1 and TSC2. These genes may inform new strategies to enhance T-DM1 therapy in the clinic.

Non-coding RNAs as key regulators of epithelial-mesenchymal transition in breast cancer

This study examines the critical role of non-coding RNAs (ncRNAs) in regulating epithelial-mesenchymal transition (EMT) in breast cancer, a prevalent malignancy with significant metastatic potential. EMT, wherein cancer cells acquire mesenchymal traits, is fundamental to metastasis. ncRNAs-such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs)-modulate EMT by influencing gene expression and signaling pathways, affecting cancer cell migration and invasion. This review consolidates recent findings on ncRNA-mediated EMT regulation and explores their diagnostic and therapeutic potential. Specifically, miRNAs inhibit EMT-related transcription factors, while lncRNAs and circRNAs regulate gene expression through interactions with miRNAs, impacting EMT progression. Given the influence of ncRNAs on metastasis and therapeutic resistance, advancing ncRNA-based biomarkers and treatments holds promise for improving breast cancer outcomes.

Prevalence and concordance of HER2-low and HER2-ultralow status between historical and rescored results in a multicentre study of breast cancer patients in China

BACKGROUND

Accurately assessing HER2-low (immunohistochemistry [IHC] 1 + and IHC 2+/in situ hybridization [ISH]-) and HER2-ultralow (IHC > 0 < 1+) is essential given the emergence of novel therapies. Thorough understanding of the reproducibility of rescoring IHC stained slides or re-staining archived tissue slides is essential.

METHODS

2,869 breast cancer patients diagnosed between July 2021 and July 2022 from 10 hospitals in China were included in this multicentre study. The prevalence of different HER2 expression levels and distribution of HER2 IHC scores were assessed by HER2 status determination from rescored historical slides. Concordance was evaluated across historical results versus rescored results, historical results versus re-stained results, and leading center results versus local site results. Clinicopathological characteristics were retrospectively analyzed as well.

RESULTS

HER2 IHC 0, IHC 1+, IHC 2+, and IHC 3 + were identified in 682 (23.8%), 871 (30.4%), 801 (27.9%), and 515 (18.0%) cases, respectively. HER2-positive, HER2-low, and HER2 IHC 0 (HER2-ultralow and IHC null) were identified in 21.7%, 54.5%, and 23.8% of cases, respectively. The prevalence of HER2-ultralow and IHC null was 10.6% and 13.2%, respectively. The concordance for HER2-ultralow was 43.3%; 30% of cases that were scored as HER2-ultralow at local sites were rescored as HER2-null and 26.7% of cases were rescored as IHC 1 + at the leading site. Overall, there was substantial agreement (83.1%) between rescored and historical IHC results. A high concordance rate of 91.7% was observed for HER2-low classification.

CONCLUSIONS

This is the first multicenter study to determine the prevalence of HER2-low and HER2-ultralow based on rescored results in the Chinese breast cancer population. The concordance analysis carries important implications for the diagnosis of HER2-low and HER2-ultralow cases in clinical practice. The relatively low concordance in identifying HER2-ultralow suggested that the reproducibility of scoring HER2-ultralow needed to be improved through training.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT05203458.

Preclinical study of inetetamab combined with atezolizumab to synergistically inhibit HER2 and PD-L1 in the treatment of ovarian cancer

Epithelial ovarian cancer (EOC) is the deadliest gynecological malignancy. Precision treatments are crucial for improving patient survival. This research explored the potential anti-tumor effects of combining inetetamab and atezolizumab for HER2+ EOC patients. The expressions of human epidermal growth factor receptor 2 (HER2) and programmed cell death ligand 1 (PD-L1) in EOC cells were evaluated. EOC cell-derived subcutaneous and peritoneal dissemination mouse models were used to evaluate the anti-tumor effects of inetetamab, with or without atezolizumab. The correlations between the expressions of HER2 and PD-L1 as well as the infiltration of T cells in tumors from patients and mice were analyzed by immunohistochemistry. Inetetamab suppressed the growth of HER2+ tumors in mouse models. HER2 overexpression increased PD-L1 levels in EOC cells. The expression level of HER2 is positively related to that of PD-L1 in the tumors of EOC patients as well as the infiltration of both CD4+ and CD8+ T cells. The combination of inetetamab and atezolizumab impeded the growth of HER2+ EOC tumors in vivo and induced a long-term anti-tumor effect with the elevated infiltration of CD103+CD8+ cells. These findings suggest that the combination of inetetamab and atezolizumab could be a promising precision treatment strategy for HER2+ EOC patients.

Advances in research and current challenges in the treatment of advanced HER2-low breast cancer

Human epidermal growth factor receptor 2 (HER2)-low breast cancer is defined as breast cancer with an immunohistochemistry (IHC) score of 1+ or 2+ and in situ hybridisation (ISH)-negative. The traditional HER2 classification (negative or positive) has limitations, with only 15%-20% of the breast cancer population being positive and suitable for HER2-targeted therapy. The new clinical study, DESTINY-Breast04, shows that trastuzumab deruxtecan (T-DXd) has a significant effect on advanced HER2-low breast cancers, a classification that accounts for approximately half of the advanced breast cancer population. However, the detection methods and evaluation criteria for HER2-low breast cancer have not yet been standardised, and the toxicity and resistance mechanisms associated with T-DXd therapy are still unclear. This article focuses on these issues and describes the progress and challenges of T-DXd-related therapy in the treatment of advanced breast cancer patients with low HER2 expression.

Pathologic response rates in HER2-low versus HER2-zero early breast cancer patients receiving neoadjuvant therapy: a systematic review and meta-analysis

BACKGROUND

Currently, the primary methods for detecting HER2 expression levels are immunohistochemistry (IHC) and in situ hybridization (ISH), with the traditional standard being a HER2-positive score of 3 + accompanied by ERBB2 gene amplification detected through ISH. However, a new entity has recently emerged: HER2-low, defined as HER2 IHC 1 + or 2 + with negative ISH. HER2-low breast cancer, representing 45-60% of all HER2-negative tumors, has distinct biological characteristics and uncertain responses to conventional HER2-targeted therapies. Recent studies suggest varied clinical outcomes, highlighting the need for further investigation into the impact of HER2-low status on treatment efficacy and prognosis.

OBJECTIVE

This meta-analysis evaluates the difference in complete pathological response (pCR), disease-free survival (DFS), and overall survival (OS) between HER2-low and HER2-zero phenotypes.

METHODS

We systematically searched the main databases PubMed, Scopus, and Web of Science for articles evaluating women in neoadjuvant therapy expressing HER2-low and HER2-zero. We computed odds ratios (ORs) or hazard ratios (HRs) using DerSimonian and Laird random-effect models for all endpoints, with 95% confidence intervals (CIs). We assessed the heterogeneity using I2 statistics. R, version 4.2.3, was used for statistical analyses.

RESULTS

38 studies totaling 70,104 patients were included. The HER2-low group accounted for 61.3% of patients while HR + status represented 52.4% in the whole research. In 67,839 women, the pCR was analyzed, which in the overall cohort analysis favored the HER2-zero group (OR 0.84; 95% CI 0.78-0.90; p = 0.000005; I2 = 15%). Subgroup analyses for triple-negative breast cancer (TNBC) and HR + patients also favored HER2-zero expression, with an OR of 0.91 (95% CI 0.83-1.0; p < 0.041; I2 = 12%) and 0.75 (95% CI 0.70-0.81; p < 0.000001; I2 = 0%), respectively. In the multivariate analysis across all patients, both DFS and OS outcomes were significantly favorable for the HER2-low expression group, with HR 0.8317 (95% CI 0.7036-0.9832; p = 0.031) for DFS and HR 0.806 (95% CI 0.663-0.979; p = 0.03) for OS.

CONCLUSION

Based on our findings, HER2-zero status is associated with a significantly higher pathological complete response (pCR) rate compared to HER2-low in early-stage breast cancer, and other survival outcomes. These results suggest that HER2-zero should be considered a prognostic factor in early-stage breast cancer and taken into account in neoadjuvant treatment planning and future clinical research.

Signaling pathway dysregulation in breast cancer

This article provides a comprehensive analysis of the signaling pathways implicated in breast cancer (BC), the most prevalent malignancy among women and a leading cause of cancer-related mortality globally. Special emphasis is placed on the structural dynamics of protein complexes that are integral to the regulation of these signaling cascades. Dysregulation of cellular signaling is a fundamental aspect of BC pathophysiology, with both upstream and downstream signaling cascade activation contributing to cellular process aberrations that not only drive tumor growth, but also contribute to resistance against current treatments. The review explores alterations within these pathways across different BC subtypes and highlights potential therapeutic strategies targeting these pathways. Additionally, the influence of specific mutations on therapeutic decision-making is examined, underscoring their relevance to particular BC subtypes. The article also discusses both approved therapeutic modalities and ongoing clinical trials targeting disrupted signaling pathways. However, further investigation is necessary to fully elucidate the underlying mechanisms and optimize personalized treatment approaches.

Signal detection and safety analysis of three tyrosine kinase inhibitors for HER-2 positive breast cancer: a retrospective study based on the FAERS database

Objective

To identify adverse event (ADE) signals of three tyrosine kinase inhibitors (TKIs) (Tucatinib, Lapatinib, and Neratinib) used for HER-2 positive breast cancer by utilizing the FAERS database, and to analyze their safety profiles to provide references for clinical risk management.

Methods

Data from the FAERS database spanning Q1 2015 to Q3 2024 were retrieved, including reports where Tucatinib, Lapatinib, or Neratinib was identified as the primary suspect drug. Disproportionality analysis (ROR, PRR) and the Comprehensive Standard method were employed to detect potential ADE signals. The distribution of ADEs across different System Organ Classifications (SOCs) was also analyzed.

Results

A total of 7,848 ADE reports were analyzed, identifying 557 significant signals. The primary ADEs were concentrated in gastrointestinal disorders, general conditions, administration site reactions, and skin and subcutaneous tissue disorders. Neratinib exhibited higher gastrointestinal toxicity, Lapatinib was associated with notable skin toxicities, and Tucatinib showed specific adverse reactions linked to combination therapies.

Conclusion

The three TKIs demonstrated distinct ADE signal profiles, with gastrointestinal, systemic, and skin toxicities being the major areas of concern. Future research should validate these findings and develop effective management strategies to enhance treatment safety and improve the quality of life for HER-2 positive breast cancer patients.

Immunohistochemical expression of epidermal growth factor receptor: prognostic value in HER2 positive breast cancer

INTRODUCTION

Epidermal Growth Factor Receptor (EGFR) expression is not well-studied in Human Epidermal Growth Factor Receptor 2 (HER2) positive breast cancer. We aim to study the prevalence of EGFR immunohistochemical expression in HER2-positive breast carcinomas and to correlate this expression with different anatomo-clinical parameters.

METHODS

It was a retrospective study involving cases of HER2-positive breast carcinoma collected at the Immuno-Histo-Cytology Department of Salah Azaïez Institute of Tunis between 2018 and 2020. An immunohistochemical study using the anti-human EGFR monoclonal antibody was performed. Cases with an overall score ≥1+ were considered positive.

RESULTS

Fifty patients were included. EGFR expression in HER2-positive breast carcinomas was more likely to occur in patients under the age of 50 (p = 0.063). It was significantly associated with the absence of lymphovascular invasion (p = 0.047). In multivariate analysis, young age, absence of lympho-vascular invasion, and high Ki67 proliferation index (>60%) were independently associated with positive EGFR expression (p = 0.047, p = 0.040, and p = 0.050, respectively).

CONCLUSION

Through this first Tunisian study, our data revealed that the immunohistochemical expression of EGFR is associated with young age, absence of lymphovascular invasion, and a high mitotic index (Ki67), which may suggest a potential predictive value for chemotherapy response.

Perioperative Considerations of Breast Cancer Neoadjuvant Treatments

Neoadjuvant treatment is increasingly being used in patients with breast cancer. Understanding the effects of neoadjuvant agents in the perioperative setting is crucial as it can affect morbidity. Understanding how these agents should be used to maximize optimal time to surgery is crucial as delays can negatively affective cancer outcomes. This review aims to discuss the perioperative considerations surgeons should be aware of prior to scheduling surgery for patients receiving chemotherapy, endocrine therapy, chemotherapy, targeted therapy, and immunotherapy.

Pan-Cancer Molecular Biomarkers: Practical Considerations for the Surgical Pathologist

Traditional anatomic pathologic classification of cancer is based on tissue of origin and morphologic and immunohistochemical characterization of the malignant cells. With the technological improvements of massively parallel or next-generation sequencing, oncogenic drivers that are shared across different tumor types are increasingly being identified and used as pan-cancer biomarkers. This approach is reflected in the growing list of Food and Drug Administration-approved tumor-agnostic therapies, including pembrolizumab in the setting of microsatellite instability and high tumor mutational burden, larotrectinib and entrectinib for solid tumors with NTRK fusions, and combined dabrafenib-trametinib for BRAF V600E-mutated neoplasms. Several other biomarkers are currently under investigation, including fibroblast growth factor receptor (FGFR), RET, and ROS1 fusions; ERBB2 amplification; and mutations in the AKT1/2/3, NF1, RAS pathway and (mitogen-activated protein kinase (MAPK) pathway. As molecular assays are increasingly incorporated into routine tumor workup, the emergence of additional pan-cancer biomarkers is likely to be a matter more of "when" than "if." In this review, we first explore some of the conceptual and technical considerations at the intersection of surgical and molecular pathology, followed by a brief overview of both established and emerging molecular pan-cancer biomarkers and their diagnostic and clinical applications.

Decoding driver and phenotypic genes in cancer: Unveiling the essence behind the phenomenon

Gray hair, widely regarded as a hallmark of aging. While gray hair is associated with aging, reversing this trait through gene targeting does not alter the fundamental biological processes of aging. Similarly, certain oncogenes (such as CXCR4, MMP-related genes, etc.) can serve as markers of tumor behavior, such as malignancy or prognosis, but targeting these genes alone may not lead to tumor regression. We pioneered the name of this class of genes as "phenotypic genes". Historically, cancer genetics research has focused on tumor driver genes, while genes influencing cancer phenotypes have been relatively overlooked. This review explores the critical distinction between driver genes and phenotypic genes in cancer, using the MAPK and PI3K/AKT/mTOR pathways as key examples. We also discuss current research techniques for identifying driver and phenotypic genes, such as whole-genome sequencing (WGS), RNA sequencing (RNA-seq), RNA interference (RNAi), CRISPR-Cas9, and other genomic screening methods, alongside the concept of synthetic lethality in driver genes. The development of these technologies will help develop personalized treatment strategies and precision medicine based on the characteristics of relevant genes. By addressing the gap in discussions on phenotypic genes, this review significantly contributes to clarifying the roles of driver and phenotypic genes, aiming at advancing the field of targeted cancer therapy.

Phthalocyanine based metal organic frameworks for electrochemical detection of human epidermal growth factor receptor 2

Herein, we report on the development of a phthalocynaine based metal organic frameworks (MOF) for the detection of human epidermal growth factor receptor 2 (HER2). Phthalocyanines (Pcs) exhibit good redox properties, hence their utilization as precursors for the synthesis of Pc based MOFs. The successful preparation of the MOF was confirmed using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Brunner Emmet Teller (BET) analysis. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were utilized for electrochemical characterization of the Co octacarboxy Pc (CoOCPc), and Co-CoOCPc-MOF modified glassy carbon electrode (GCE). Differential pulse votammetry was employed for detection of HER2, which is a biomarker for cancer. The selectivity towards HER2 biomarker was accomplished by attaching an aptamer (Apt) onto the MOF modified glassy carbon surface. The GCE/Co-CoOCPc-MOF/Nf/Apt (Nf = Nafion) showed excellent analytical parameters with lowest limit of detection of 5.4 × 10 ng/mL, good repeatability and stability.

Transgenic overexpression of the miR-200b/200a/429 cluster prevents mammary tumor initiation in Neu/Erbb2 transgenic mice

Although significant progress in the treatment of breast cancer has been achieved, toxic therapies would not be required if breast cancer could be prevented from developing in the first place. While breast cancer prevention is difficult to study in humans due to long disease latency and stochastic cancer development, transgenic mouse models with 100% incidence and defined mammary tumor onset, provide excellent models for tumor prevention studies. In this study, we used Neu/Erbb2 transgenic mice (MTB-TAN) as a model of human HER2+ breast cancer to investigate whether a family of microRNAs, known as the miR-200 family, can prevent mammary tumor development. Overexpression of Neu induced palpable mammary tumors in 100% of the mice within 38 days of Neu overexpression. When the miR-200b/200a/429 cluster was co-overexpressed with Neu in the same mammary epithelial cells (MTB-TANba429 mice), the miR-200b/200a/429 cluster prevented Neu from inducing mammary epithelial hyperplasia and mammary tumor development. RNA sequencing revealed alterations in the extracellular matrix of the mammary gland and a decrease in stromal cells including myoepithelial cells in Neu transgenic mice. Immunohistochemistry for smooth muscle actin confirmed that mammary epithelial cells in control and MTB-TANba429 mice were surrounded by a layer of myoepithelial cells and these myoepithelial cells were lost in MTB-TAN mice with hyperplasia. Thus, we have shown for the first time that elevated expression of miR-200 family members in mammary epithelial cells can completely prevent mammary tumor development in Neu transgenic mice possibly through regulating myoepithelial cells.

Subcutaneous vs Intravenous Trastuzumab/Pertuzumab: A Time and Motion Substudy of a Phase II Trial of Adjuvant Trastuzumab/Pertuzumab for Stage I HER2+ Breast Cancer (ADEPT trial)

PURPOSE

The time required for in-clinic drug administration can substantially affect breast cancer patients' quality of life. Subcutaneous (SC) drug administration, as opposed to intravenous (IV), may reduce this time commitment. This study sought to estimate the difference in time burden between IV and SC administration of trastuzumab and pertuzumab (HP).

METHODS

We prospectively enrolled a subcohort of patients participating in the ADEPT trial (ClinicalTrials.gov identifier: NCT04569747, investigating adjuvant HP plus endocrine therapy for stage I human epidermal growth factor receptor 2-positive breast cancer) to this single-arm crossover time and motion substudy. Patients received two cycles of IV HP followed by two cycles of SC HP. During each cycle, time points in drug preparation and administration were captured. The primary end point was total patient time in the treatment chair. Additional end points included total patient treatment experience time and total pharmacy workflow time. A sample size of 22 patients was estimated to provide 90.7% power with two-sided alpha .05 to detect a difference of 70 minutes in the primary end point by treatment arm (IV v SC).

RESULTS

Twenty-two patients were enrolled. The mean total patient time in the treatment chair was 61.8 minutes shorter with SC versus IV HP (22.5 v 84.3 minutes; P < .0001). The mean total patient treatment experience time (incorporating time spent waiting for treatment initiation and time spent in the treatment chair) was 81.8 minutes shorter for SC administration (96 v 177.8 minutes; P < .0001). The pharmacy workflow time was 78.2 minutes shorter for SC versus IV formulation (41 v 119.2 minutes; P < .0001).

CONCLUSION

SC administration of HP shortened patient time burden by approximately 1 hour. SC drug administration can facilitate faster workflows for health care professionals and improve patients' breast cancer treatment experience.

Tucatinib in the treatment of HER2-overexpressing gastrointestinal cancers: current insights and future prospects

INTRODUCTION

Over the past 20 years, the treatment landscape of HER2-amplified tumors has considerably evolved. Until now, no approved targeted therapies were available for patients with HER2-amplified metastatic colorectal cancer (mCRC). Tucatinib, a highly selective tyrosine kinase inhibitor, demonstrated significant efficacy in combination with trastuzumab in patients with refractory mCRC, leading to its approval by the Food and Drug Administration (FDA).

AREAS COVERED

This review dives into the efficacy of tucatinib-based regimens in gastrointestinal malignancies, with a focus on the pivotal MOUNTAINEER trial, which led to the FDA approval of tucatinib plus trastuzumab in chemo-refractory HER2-amplified mCRC. Additionally, ongoing trials are exploring tucatinib in earlier treatment lines and across other gastrointestinal cancers, including biliary tract, gastric, and pancreatic malignancies. The mechanistic basis of dual HER2 inhibition and its implications for clinical practice are discussed.

EXPERT COMMENTARY

The future of tucatinib-based therapeutic strategies in GI malignancies depends on their integration into different treatment lines. Addressing acquired resistance using liquid biopsy-guided strategies and other TKIs like lapatinib will be paramount to improve outcomes.

Breast Cancer and Meningioma Risk: A Mendelian Randomization Study

BACKGROUND

The exact nature of the link between breast cancer and meningiomas is unknown, although observational studies have shown a correlation between the two. Using a two-sample Mendelian randomization (MR) strategy, we aimed to investigate the effect of breast cancer on meningiomas.

METHODS

Three sets of genetic instruments were utilized in this study based on publicly available genetic summary data. For breast cancer, we selected 62 strongly associated SNPs; separate datasets were curated for HER2-positive and HER2-negative subtypes. MR analyses included outlier testing, MR-Egger regression, MR-PRESSO, weighted median, and inverse variance weighted approaches.

RESULTS

The inverse variance weighted analysis demonstrated significant evidence for breast cancer's effect on meningioma risk (OR = 1.213, 95% CI = 1.054-1.396, p = 0.007), supported by MR-Egger (OR = 1.456, 95% CI = 1.066-1.988, p = 0.021) though not by the weighted median method (OR = 1.095, 95% CI = 0.914-1.311, p = 0.326). Inverse variance weighting specifically revealed a significant association between HER2-positive breast cancer and meningioma incidence (OR = 1.203, 95% CI = 1.048-1.381, p = 0.009). Furthermore, breast cancer risk was associated with an increased incidence of malignant meningiomas (OR = 1.64, 95% CI = 1.12-2.40, p = 0.011).

CONCLUSIONS

This represents the first MR study investigating the causal relationship between breast cancer and meningiomas. Our findings support the hypothesis that breast cancer may increase meningioma risk.

Super-resolution microscopy as a drug discovery tool

At the turn of the century a fundamental resolution barrier in fluorescence microscopy known as the diffraction limit was broken, giving rise to the field of super-resolution microscopy. Subsequent nanoscopic investigation with visible light revolutionised our understanding of how previously unknown molecular features give rise to the emergent behaviour of cells. It transpires that the devil is in these fine molecular details, and essential nanoscale processes were found everywhere researchers chose to look. Now, after nearly two decades, super-resolution microscopy has begun to address previously unmet challenges in the study of human disease and is poised to become a pivotal tool in drug discovery.

EGFR-HER2 Transactivation Viewed in Space and Time Through the Versatile Spectacles of Imaging Cytometry-Implications for Targeted Therapy

Ligand-induced formation of signaling platforms composed of homo- and/or heterodimers of receptor tyrosine kinases is considered essential for their activation and consequential contribution to the progression of many cancers. Epidermal Growth Factor Receptor (EGFR) acts as a signal receiver upon EGF binding and produces mitogenic input for many cells also through receptor-heterodimerization with its ligandless partner, Human Epidermal growth factor Receptor 2 (HER2). Ligand-driven transactivation is a key step leading to changes in the cell surface pattern of EGFR and HER2; their interaction plays a key role in various malignancies, especially when HER2 molecules are overexpressed. Our clinically relevant model system is the SK-BR-3 breast tumor cell line, overexpressing HER2 and moderately expressing EGFR. This cell line shows significant dependency on EGF-driven HER2 signaling. We studied changes in the interaction between EGFR and HER2 in the cell membrane upon EGF binding, applying various biophysical approaches with different time scales. Changes in molecular proximity were characterized by fluorescence lifetime imaging microscopy (FLIM) techniques assessing Förster resonance energy transfer (FRET), which confirmed the ligand-enhanced interaction of EGFR and HER2, followed by an increase in HER2 homoassociation. EGF binding and transactivation were reflected in the phosphorylation of both receptor types as well. At the same time, superresolution Airyscan microscopy and fluorescence correlation and cross-correlation spectroscopy (FCS/FCCS), sensitive to changes in the size of stationary and diffusing aggregates, respectively, have revealed cyclic increases in the aggregation and stable co-diffusion of membrane-localized HER2, possibly caused by internalization and recycling, eventually leading to a new equilibrium. Such dynamic fluctuation of receptor interaction may open a window for the binding of therapeutic antibodies that are aimed at inhibiting heterodimerization, such as pertuzumab. The complementary array of state-of-the-art imaging cytometry approaches thus demonstrates a spatiotemporal pattern of spontaneous and induced receptor aggregation states that could provide mechanistic insights into the potential success of targeted therapies directed at the HER family of receptor tyrosine kinases.

Navigating heme pathways: the breach of heme oxygenase and hemin in breast cancer

Breast cancer remains a significant global health challenge, with diverse subtypes and complex molecular mechanisms underlying its development and progression. This review comprehensively examines recent advances in breast cancer research, with a focus on classification, molecular pathways, and the role of heme oxygenases (HO), heme metabolism implications, and therapeutic innovations. The classification of breast cancer subtypes based on molecular profiling has significantly improved diagnosis and treatment strategies, allowing for tailored approaches to patient care. Molecular studies have elucidated key signaling pathways and biomarkers implicated in breast cancer pathogenesis, shedding light on potential targets for therapeutic intervention. Notably, emerging evidence suggests a critical role for heme oxygenases, particularly HO-1, in breast cancer progression and therapeutic resistance, highlighting the importance of understanding heme metabolism in cancer biology. Furthermore, this review highlights recent advances in breast cancer therapy, including targeted therapies, immunotherapy, and novel drug delivery systems. Understanding the complex interplay between breast cancer subtypes, molecular pathways, and innovative therapeutic approaches is essential for improving patient outcomes and developing more effective treatment strategies in the fight against breast cancer.

Heteronemin suppresses EGF‑induced proliferation through the PI3K/PD‑L1 signaling pathways in cholangiocarcinoma

Epidermal growth factor (EGF) binds with its surface receptor to stimulate gene expression and cancer cell proliferation. EGF stimulates cancer cell growth via phosphoinositide 3‑kinase (PI3K) and programmed cell death ligand 1 (PD‑L1) pathways. As an integrin αvβ3 antagonist, heteronemin exhibits potent cytotoxic effects against cancer cells. It inhibits critical signal transduction pathways promoted by the EGF. In the current study, EGF‑induced signal activation and proliferative effects were investigated in cholangiocarcinoma cells and its molecular targets using qPCR and western blotting analyses. In addition, cell viability assays were performed to assess the growth effects of EGF and heteronemin. Heteronemin reversed the effects of EGF and was further enhanced by blockage of PI3K's activity. In summary, EGF stimulates cholangiocarcinoma cell growth. On the other hand, heteronemin inhibited PI3K activation and PD‑L1 expression to reverse the stimulative effects of EGF‑induced gene expression and proliferation in cholangiocarcinoma cells.