Tumor enhancement and shrinkage pattern in dynamic contrast-enhanced magnetic resonance imaging for predicting pathologic complete response after human epidermal growth factor receptor 2 (HER2)-targeted therapy in breast cancer.

Background: Targeted therapy with neoadjuvant chemotherapy for patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer has increased the rates of pathological complete response (pCR) and breast preservation surgery and improved the overall disease-free survival rate. This study aimed to determine whether tumor enhancement and shrinkage patterns in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can predict the efficacy of targeted therapy in patients with HER2-positive breast cancer and differentiate pCR from non-pCR. Methods: The data of 64 patients with HER2-positive breast cancer who received targeted therapy prior to surgery were retrospectively collected. All patients had complete postoperative pathological data. The pretreatment evaluation of the tumor enhancement pattern and the shrinkage pattern after two treatment cycles were assessed. The difference in the enhancement and shrinkage patterns between the pCR and non-pCR groups was evaluated via the χ2 test. Logistic regression analysis was used to assess the value of enhancement and shrinkage patterns for predicting pCR in patients with HER2-positive breast cancer. Results: There were statistically significant differences in tumor size, estrogen receptor (ER) status, lymph node metastasis, enhancement pattern, and shrinkage pattern between the pCR and non-pCR cases. Patients with a tumor size ≤20 mm were likely to achieve pCR. ER status, lymph node metastasis, and enhancement and shrinkage patterns each had good precision for predicting pCR, and the combination of enhancement and shrinkage patterns had the highest prediction accuracy. Multivariate logistic regression analysis indicated that only enhancement pattern had a significant predictive value. Conclusions: Among patients with HER2-positive breast cancer, those with tumor size ≤20 mm, ER-negative status, no lymph node metastases, and mass enhancement and concentric shrinkage patterns are more likely to achieve pCR. Mass enhancement combined with concentric shrinkage had the highest accuracy in predicting pCR, indicating that preoperative imaging may be useful for guiding clinical decisions regarding targeted treatments.

Obesity-Associated Breast Cancer: Analysis of Risk Factors and Current Clinical Evaluation.

Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Additionally, obese and postmenopausal women are at higher risk of all-cause and breast cancer-specific mortality compared with non-obese women with breast cancer. In this context, increased levels of estrogens, excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, adipocyte-derived adipokines, hypercholesterolemia, and excessive oxidative stress contribute to the development of breast cancer in obese women. Genetic evaluation is an integral part of diagnosis and treatment for patients with breast cancer. Despite trimodality therapy, the four-year cumulative incidence of regional recurrence is significantly higher. Axillary lymph nodes as well as primary lesions have diagnostic, prognostic, and therapeutic significance for the management of breast cancer. In clinical setting, because of the obese population primary lesions and enlarged lymph nodes could be less palpable, the diagnosis may be challenging due to misinterpretation of physical findings. Thereby, a nomogram has been created as the "Breast Imaging Reporting and Data System" (BI-RADS) to increase agreement and decision-making consistency between mammography and ultrasonography (USG) experts. Additionally, the "breast density classification system," "artificial intelligence risk scores," ligand-targeted receptor probes," "digital breast tomosynthesis," "diffusion-weighted imaging," "18F-fluoro-2-deoxy-D-glucose positron emission tomography," and "dynamic contrast-enhanced magnetic resonance imaging (MRI)" are important techniques for the earlier detection of breast cancers and to reduce false-positive results. A high concordance between estrogen receptor (ER) and progesterone receptor (PR) status evaluated in preoperative percutaneous core needle biopsy and surgical specimens is demonstrated. Breast cancer surgery has become increasingly conservative; however, mastectomy may be combined with any axillary procedures, such as sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection whenever is required. As a rule, SLNB-guided axillary dissection in breast cancer patients who have clinically axillary lymph node-positive to node-negative conversion following neoadjuvant chemotherapy is recommended, because lymphedema is the most debilitating complication after any axillary surgery. There is no clear consensus on the optimal treatment of occult breast cancer, which is much discussed today. Similarly, the current trend in metastatic breast cancer is that the main palliative treatment option is systemic therapy.

Clinical best practices in interdisciplinary management of human epidermal growth factor receptor 2 antibody-drug conjugates-induced interstitial lung disease/pneumonitis: An expert consensus in China.

Antibody-drug conjugates (ADCs) have demonstrated effectiveness in treating various cancers, particularly exhibiting specificity in targeting human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Recent advancements in phase 3 clinical trials have broadened current understanding of ADCs, especially trastuzumab deruxtecan, in treating other HER2-expressing malignancies. This expansion of knowledge has led to the US Food and Drug Administration's approval of trastuzumab deruxtecan for HER2-positive and HER2-low breast cancer, HER2-positive gastric cancer, and HER2-mutant nonsmall cell lung cancer. Concurrent with the increasing use of ADCs in oncology, there is growing concern among health care professionals regarding the rise in the incidence of interstitial lung disease or pneumonitis (ILD/p), which is associated with anti-HER2 ADC therapy. Studies on anti-HER2 ADCs have reported varying ILD/p mortality rates. Consequently, it is crucial to establish guidelines for the diagnosis and management of ILD/p in patients receiving anti-HER2 ADC therapy. To this end, a panel of Chinese experts was convened to formulate a strategic approach for the identification and management of ILD/p in patients treated with anti-HER2 ADC therapy. This report presents the expert panel's opinions and recommendations, which are intended to guide the management of ILD/p induced by anti-HER2 ADC therapy in clinical practice.

Narrative review on the evolving role of HER2/neu targeting in uterine serous cancers.

Background and Objective: Serous endometrial cancers (ECs) are an aggressive histotype of ECs which are disproportionately responsible for 40% of cancer-specific mortality rates despite constituting only 5-10% of all uterine cancers in incidence. In recent times, it has become increasingly evident that about 20-40% of uterine serous cancers (USCs) have molecular alterations in ERBB2 pathway with human epidermal growth factor receptor 2 (HER2/neu) amplification or overexpression. We summarise the evidence on genetic and molecular alterations in HER2/neu pathway in USC with a focus on testing criteria, targeting agents and resistance mechanisms. Methods: We conducted a database search of PubMed/Medline up to 28th February 2023 for articles published in the English language using pre-defined search terms. One hundred and seventy-one relevant articles were subsequently reviewed for eligibility and inclusion in the review. Key Content and Findings: The Cancer Genome Atlas (TCGA) classification is a significant development in the molecular profiling of ECs with a positive impact on the treatment of these tumors including USCs. Testing criteria for HER2/neu in USC with immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) has evolved in more than a decade with progress made towards EC specific testing guidelines. The findings of a recent phase III study have led to the development of practice changing guidelines towards improving patient outcomes. Conclusions: Molecular aberration in the HER2/neu pathway contributes to the aggressive behaviour of USC. Considering the clinical benefit conferred by HER2/neu targeted therapy, HER2/neu testing is recommended for all cases of serous EC in advanced and recurrent settings. Trastuzumab in combination with platinum and taxanes based chemotherapy is the recommended treatment option for patients with advanced or recurrent serous cancers who test positive to HER2/neu. Clinical trials on targeted therapy are ongoing and future research should focus on selection of patients who will derive the most benefit from such therapy.

Development and biological evaluation of 68Ga-labeled peptides for potential application in HER2-positive colorectal cancer.

Colorectal cancer (CRC) is among the most lethal and prevalent malignancies in the world. Human epidermal growth factor receptor 2 (HER2) is a promising target for the diagnosis and treatment of CRC. In this study, we aimed to design, synthesize and label peptide-based positron emission tomography (PET) tracers targeting HER2-positive CRC, namely [68Ga]Ga-ES-01 and [68Ga]Ga-ES-02. The results show that [68Ga]Ga-ES-01 and [68Ga]Ga-ES-02 possessed hydrophilicity, rapid pharmacokinetic properties and excellent stabilities. [68Ga]Ga-ES-02 demonstrated higher binding affinity (Kd = 24.29 ± 4.95 nM) toward the HER2 in CRC. In HER2-positive HT-29 CRC xenograft mouse model, PET study showed specific tumor uptake after injection of [68Ga]Ga-ES-02 (SUV15min max = 0.87 ± 0.03; SUV30min max = 0.64 ± 0.02). In biodistribution study, the T/M ratios of 68Ga-ES-02 at 30 min after injection reached a maximum of 4.07 ± 0.34. In summary, we successfully synthesized and evaluated two novel peptide-based PET tracers. Our data demonstrate that [68Ga]Ga-ES-01/02 is capable of HER2-positive colorectal cancer, with [68Ga]Ga-ES-02 showing superior imaging effect, enhanced targeting, and increased specificity.

Define Critical Parameters of Trastuzumab-Mediated ADCC Assays via Assay Optimization Processes, Focusing on the Impact of Cryopreserved Effector Cells on Assay Performance.

The mechanisms of mAb-induced ADCC have been well established. However, the ADCC bioassays used to quantify mAb-induced ADCC require continued development/refinement to properly assess and compare the potency of newly developed therapeutic mAbs and biosimilars to meet regulatory requirements. We used trastuzumab and a lactate dehydrogenase (LDH)-based ADCC bioassay as a model to define critical parameters of the ADCC bioassay, describing how several bioassay parameters, including preparation of effector cells, E/T ratio, target cell selection, bioassay media components, and treatment time can influence the data quality of the ADCC activity. We confirm that a 4 to 24 h recovery cultivation is required to restore peripheral blood mononuclear cells (PBMCs) and natural killer (NK) cell activity toward ADCC when using cryopreserved PBMCs. Furthermore, we delineated the cellular mechanisms underlying the restored ADCC activity following the recovery cultivation. We observed that CD69, an early marker of NK cell activation, was upregulated and a new subset CD56dim/CD16dim population was dramatically increased in the recovered NK cells, which led to an increase in expression and secretion of perforin, granzyme B, and cytokine production. This study provides comprehensive technical insights into ADCC bioassay optimization to inform trastuzumab biosimilar development. The knowledge gained from this study can also be leveraged to guide bioassay development for therapeutic mAbs with ADCC as the primary mechanism of action.

Best practices for achieving consensus in HER2-low expression in breast cancer: current perspectives from practising pathologists.

AIMS: Human epidermal growth factor receptor 2 (HER2) expression is an important biomarker in breast cancer (BC). Most BC cases categorised as HER2-negative (HER2-) express low levels of HER2 [immunohistochemistry (IHC) 1+ or IHC 2+/in-situ hybridisation not amplified (ISH-)] and represent a clinically relevant therapeutic category that is amenable to targeted therapy using a recently approved HER2-directed antibody-drug conjugate. A group of practising pathologists, with expertise in breast pathology and BC biomarker testing, outline best practices and guidance for achieving consensus in HER2 IHC scoring for BC. METHODS AND RESULTS: The authors describe current knowledge and challenges of IHC testing and scoring of HER2-low expressing BC and provide best practices and guidance for accurate identification of BCs expressing low levels of HER2. These expert pathologists propose an algorithm for assessing HER2 expression with validated IHC assays and incorporate the 2023 American Society of Clinical Oncology and College of American Pathologist guideline update. The authors also provide guidance on when to seek consensus for HER2 IHC scoring, how to incorporate HER2-low into IHC reporting and present examples of HER2 IHC staining, including challenging cases. CONCLUSIONS: Awareness of BC cases that are negative for HER protein overexpression/gene amplification and the related clinical relevance for targeted therapy highlight the importance of accurate HER2 IHC scoring for optimal treatment selection.

Synthesis and evaluation of antibody-drug conjugates with high drug-to-antibody ratio using dimaleimide-DM1 as a linker- payload.

The notable characteristics of recently emerged Antibody-Drug Conjugates (ADCs) encompass the targeting of Human Epidermal growth factor Receptor 2 (HER2) through monoclonal antibodies (mAbs) and a high ratio of drug to antibody (DAR). The achievements of Kadcyla® (T-DM1) and Enhertu® (T-Dxd) have demonstrated that HER2-targeting antibodies, such as trastuzumab, have shown to be competitive in terms of efficacy and price for development. Furthermore, with the arrival of T-Dxd and Trodelvy®, high-DAR (7-8) ADCs, which differ from the moderate DAR (3-4) ADCs that were formerly regarded as conventional, are being acknowledged for their worth. Following this trend of drug development, we endeavored to develop a high-DAR ADC using a straightforward approach involving the utilization of DM1, a highly potent substance, in combination with the widely recognized trastuzumab. To achieve a high DAR, DM1 was conjugated to reduced cysteine through the simple design and synthesis of various dimaleimide linkers with differing lengths. Using LC and MS analysis, we have demonstrated that our synthesis methodology is uncomplicated and efficacious, yielding trastuzumab-based ADCs that exhibit a remarkable degree of uniformity. These ADCs have been experimentally substantiated to exert an inhibitory effect on cancer cells in vitro, thus affirming their value as noteworthy additions to the realm of ADCs.

The efficacy and safety of trastuzumab and albumin-bound paclitaxel with or without pyrotinib as neoadjuvant therapy for HER2-positive breast cancer: a prospective observational cohort study.

Background: In the past few years, the combination of trastuzumab and paclitaxel has become an important option for human epidermal growth factor receptor-2 (HER2)-positive breast cancer. Small molecule tyrosine kinase inhibitors (TKIs) can bring clinical benefit to HER2-positive breast cancer patients. However, the efficacy and safety of these two regimens have not been compared. This study explored the efficacy and safety of pyrotinib combined with trastuzumab and albumin-bound paclitaxel (nab-paclitaxel). Methods: Patients with newly diagnosed HER2-positive early or locally advanced breast cancer treated at The Tumor Hospital of Mudanjiang City from November 2020 to June 2022 were included. The control group received pertuzumab in combination with nab-paclitaxel, whereas the pyrotinib group received pyrotinib in combination with pertuzumab and nab-paclitaxel as treatment, in a 3-week cycle for 4 cycles. The primary endpoints of this study were total pathological complete response (tpCR) rate, breast pathological complete response (bpCR) rate, and the secondary endpoints included progression-free survival (PFS), objective response rate (ORR), and the occurrence of adverse events (AEs). Results: A total of 72 patients were enrolled in the study and completed the study treatment. Baseline characteristics were well balanced between these two arms. In the control group, the tPCR rate was 23.68%, and the bpCR rate was 47.36%. In the pyrotinib group, the tPCR rate was 47.06%, and the bpCR rate was 64.71%. The tPCR rate in the pyrotinib group was significantly higher than that in the control group (P=0.049). The ORR in the pyrotinib group (67.65%) was significantly higher than that in the control group (42.11%, P=0.04 ). The median PFS (mPFS) for the control group was 9.24 months, with a mean PFS of 10.01±0.44 months [95% confidence interval (CI): 9.14-10.88 months]. In the pyrotinib group, mPFS was 9.74 months, with a mean PFS of 11.25±0.29 months (95% CI: 10.67-11.82 months). The PFS in the pyrotinib group was significantly longer than that in the control group (P=0.045). Safety results showed that the overall incidence of AEs in the control group was 68.42%, with a 3-grade adverse reaction rate of 21.05%. In the pyrotinib group, the overall incidence of AEs was 79.41%, with a 3-grade adverse reaction rate of 29.41%. The difference between the two groups was not statistically significant (P>0.05). Conclusions: Pyrotinib group in neoadjuvant treatment for HER2 positive breast cancer has obvious short-term efficacy advantages over control group. This treatment regimen can prolong PFS for 1 year, and the safety during medication is controllable. This study still has some limitations, with the relatively small sample size and relatively short follow-up period, and a further large-scale, multicenter, randomized controlled trial is necessary to verify the clinical value of this dual-target treatment regimen.

PET Molecular Imaging in Breast Cancer: Current Applications and Future Perspectives.

Positron emission tomography (PET) plays a crucial role in breast cancer management. This review addresses the role of PET imaging in breast cancer care. We focus primarily on the utility of 18F-fluorodeoxyglucose (FDG) PET in staging, recurrence detection, and treatment response evaluation. Furthermore, we delve into the growing interest in precision therapy and the development of novel radiopharmaceuticals targeting tumor biology. This includes discussing the potential of PET/MRI and artificial intelligence in breast cancer imaging, offering insights into improved diagnostic accuracy and personalized treatment approaches.

Clinical characteristics, treatment patterns, and outcomes in adult patients with germline BRCA1/2-mutated, HER2-negative advanced breast cancer: a retrospective medical record review in the United States.

Aim: To examine clinical characteristics, real-world treatment patterns, and health outcomes among patients with germline BRCA1/2-mutated, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC). Methods: A retrospective analysis was conducted using medical records from patients with HER2-negative ABC with BRCA1/2 mutation who received cytotoxic chemotherapy. Data were stratified into groups with triple-negative breast cancer (TNBC) or hormone receptor-positive (HR+)/HER2-negative diagnoses. Time-to-event outcomes (i.e., real-world progression-free survival [rwPFS] and overall survival [OS]) were calculated to summarize health outcomes. Results: When diagnosed with ABC, most patients were younger than 60 years (mean age = 57.3 years), were white (76.4%), and had a family history of BRCA-related cancer (71.5%). A total of 305 patient records were examined; 194 patients (63.6%) had advanced TNBC, and 111 patients (36.4%) had HR+/HER2-negative ABC. Chemotherapy was primarily used as first-line treatment for both subgroups, but the TNBC subgroup received poly (ADP-ribose) polymerase (PARP) inhibitors at triple the rate as a second-line treatment and double the rate as a third-line treatment compared with the HR+/HER2-negative subgroup. Two-year OS rates were similar between the TNBC (73.9%) and the HR+/HER2-negative subgroups (77.0%), and anemia, nausea, and neutropenia were the most commonly reported toxicities across all treatments. Conclusion: Clinicians should consider the use of targeted agents such as PARP inhibitors in earlier lines of therapy for ABC given the growing evidence that PARP inhibitors may improve PFS compared with chemotherapy while potentially offering a more manageable toxicity profile and improved quality of life.

The emerging predictive and prognostic role of HER2 in HER2-negative early breast cancer: a retrospective study.

PURPOSE: Many patients with early breast cancer (eBC) undergoing neoadjuvant chemotherapy do not achieve pathological complete response (pCR), which is a prognostic factor. We examined the role of HER2-low expression in predicting pCR and prognosis in HER2-negative eBC. METHODS: We evaluated patients with stage I-III HER2-negative BC, treated between 2013 and 2023 at The Royal Marsden NHS Foundation Trust, London. Tumors were classified based on estrogen receptor (ER) status and into HER2-low and HER2-zero subgroups. We analyzed pCR rates, relapse-free survival (RFS) and overall survival (OS). RESULTS: 754 patients were included in the analysis. pCR rate was 8.9% in the ER+ /HER2-low, 16.5% in the ER+ /HER2-zero, 38.9% in the ER- ER-/HER2-low and 35.9% in the ER-/HER2-zero eBC (p < 0.001). Multivariable analysis showed a significantly lower pCR rate in HER2-low compared to HER2-zero BC in the ER+ subgroup. At a median follow-up of 63.8 months (59.9-67.4), we observed longer OS in HER2-low compared to HER2-zero patients in the overall and in the ER+ population. There was no predictive or prognostic impact of HER2-low status in the ER- population. CONCLUSION: This study supports the interpretation of HER2 status as a possible prognostic and predictive biomarker for HER2-negative eBC, especially among patients with ER+ disease.

Association between human epidermal growth factor receptor 2 status, namely low and zero expression, and prognosis in hormone receptor-positive breast cancer: a single-center retrospective study.

Background: The recently developed anti-human epidermal growth factor receptor 2 (HER2) therapy has substantially improved the prognosis of HER2-positive breast cancer. The DESTINY-Breast04 trial results showed that trastuzumab deruxtecan (T-DXd) significantly prolonged the survival of patients with HER2-low breast cancer, thus presenting a paradigm shift in anti-HER2 therapy. This may facilitate a change in the treatment strategy for HER2-low breast cancer. However, the implication of HER2-low in hormone receptor (HR)-positive breast cancer is unclear. In this retrospective study, we aimed to reveal the association between HER2 status, namely HER2-low and HER2-zero, and prognosis in HR-positive breast cancer. Methods: We collected the data of 247 patients with estrogen receptor (ER)-positive/HER2-negative breast cancer (159 with HER2-low and 88 with HER2-zero breast cancer) who underwent surgery. Patients were divided into HER2-low and HER2-zero groups. Univariate analysis was performed to evaluate the baseline characteristics using the Wilcoxon rank sum test and Fisher's exact test. Survival analysis of the HER2-low and HER2-zero groups was performed using the Kaplan-Meier method. Results: The median observation period was 2,706 days, and the median period until recurrence was 1,380 days; 25 patients (10%) had recurrences. Age (P=0.004) and menopausal status (P=0.04) were significant variables in the univariate analysis of baseline characteristics. In the subgroup analysis of luminal A- and B-like breast cancers, there was a significant difference in overall survival (OS) only in patients with luminal A-like breast cancer, but relapse-free survival (RFS) of the HER2-low luminal B-like cancer subgroups tended to be relatively short. Conclusions: We inferred that the HER2-low and HER2-zero statuses do not affect the RFS and OS of patients with ER-positive breast cancer. The prognostic significance of HER2-low or HER2-zero status in luminal A- and B-like breast cancers might differ, and a new treatment strategy is required for the HER2-low subgroup.

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.

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.

Short-term efficacy and safety of neoadjuvant pyrotinib plus taxanes for early HER2-positive breast cancer: a single-arm exploratory phase II trial.

Background: The effectiveness and safety of pyrotinib have been substantiated in human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (BC). However, the role of pyrotinib as a single HER2 blockade in neoadjuvant setting among BC patients has not been studied. The objective of this study was to evaluate the efficacy and tolerability of pyrotinib plus taxanes as a novel neoadjuvant regimen in patients with HER2-positive early or locally advanced BC. Methods: In this single-arm exploratory phase II trial, patients with treatment-naïve HER2-positive BC (stage IIA-IIIC) received pyrotinib 400 mg once daily and taxanes [docetaxel 75 mg/m2 or nanoparticle albumin-bound (nab)-paclitaxel 260 mg/m2 every 3 weeks, or paclitaxel 80 mg/m2 weekly] for a total of four 21-day cycles before surgery. Efficacy assessment was based on pathological and clinical measurements. The primary endpoint of this study was the total pathological complete response (tpCR) rate. The secondary endpoints included breast pCR (bpCR) rate, investigator-assessed objective response rate (ORR) and adverse events (AEs) profiles. Results: From 1 September 2021 to 30 December 2022, a total of 31 patients were enrolled. One patient was withdrawn due to unbearable skin rash after the second cycle of neoadjuvant therapy. The majority of the intention-to-treat (ITT) population was premenopausal (54.8%), had large tumors (90.3%) and metastatic nodes (58.1%) at diagnosis and hormone-receptor positive tumors (64.5%). Most participants used nab-paclitaxel (74.2%) and received mastectomy (67.7%) after neoadjuvant treatment. The tpCR and bpCR rates were 48.4% [95% confidence interval (CI): 30.8-66%] and 51.6% (95% CI: 34-69.2%), respectively. Grade ≥3 treatment-related AEs were observed in 16.1% (5/31) of the ITT population, including diarrhea (n=2, 6.5%), hand and foot numbness (n=1, 3.2%), loss of appetite (n=1, 3.2%), and skin rash (n=1, 3.2%). AE related dose reduction or pyrotinib interruption was not required. Conclusions: In female patients with HER2-positive non-metastatic BC, neoadjuvant pyrotinib monotherapy plus taxanes appears to show promising clinical benefit and controllable AEs [Chinese Clinical Trial Registry (ChiCTR2100050870)]. The long-term efficacy and safety of this regime warrant further verification.

Clinical significance of CD166 and HER-2 in different types of gastric cancer

Introduction Cluster of differentiation 166 (CD166), a cancer stem cell (CSC) marker, and human epidermal growth factor receptor 2 (HER-2) are expressed in a diversity of malignancies and is associated with tumor progression. Although studies regarding the importance of CSC markers and HER-2 in gastric cancer (GC) have rapidly developed, their clinicopathological, prognosis, and diagnosis value still remain unsatisfying in GC. Therefore, the present study aims to investigate the clinical, prognostic, and diagnostic significance of CD166 and HER-2 in different histological types of GC. Materials and methods Bioinformatic analysis was applied to determine the clinical importance of CD166 and HER-2 expression based on their tissue localization in primary GC tumors and the normal adjacent samples. The expression patterns, clinical significance, prognosis, and diagnosis value of CD166 and HER-2 proteins in tissue microarrays (TMAs) of 206 GC samples, including Signet Ring Cell (SRC) and intestinal types and also 28 adjacent normal tissues were evaluated using immunohistochemistry (IHC). Results The results indicated that the expression of CD166 (membranous and cytoplasmic) and HER-2 were significantly up-regulated in tumor cells compared to adjacent normal tissues (P = 0.010, P < 0.001, and P = 0.011, respectively). A statistically significant association was detected between a high level of membranous expression of CD166 and lymphovascular invasion (P = 0.006); We also observed a statistically significant association between high cytoplasmic expression of CD166 protein and more invasion of the subserosa (P = 0.040) in the SRC type. In contrast, there was no correlation between the expression of HER-2 and clinicopathologic characteristics. Both CD166 and HER-2 showed reasonable accuracy and high specificity as diagnostic markers (AU)

Preparation, Characterization, and Radiolabeling of Anti-HER2 scFv With Technetium Tricarbonyl and Stability Studies.

Breast cancer is the most common diagnosed cancer, and the second cause of cancer death among women, worldwide. HER2 overexpression occurred in approximately 15% to 20% of breast cancers. Invasive biopsy method has been used for detection of HER2 overexpression. HER2-targeted imaging via an appropriate radionuclide is a promising method for sensitive and accurate identification of HER2+ primary and metastatic lesions. 99mTc-anti-HER2 scFv can specifically target malignancies and be used for diagnosis of the cancer type and metastasis as well as treatment of breast cancer. We radiolabeled anti-HER2 scFv that was expressed in Escherichia coli and purified through Ni-NTA resin under native condition with 99mTc-tricarbonyl formed from boranocarbonate. HER2-based ELISA, BCA, TLC, and HPLC were used in this study. In the current study, anti-HER2 scFv was lyophilized before radiolabeling. It was found that freeze-drying did not change the binding activity of anti-HER2 scFv to HER2. Results demonstrated direct anti-HER2 scFv radiolabeling by 99mTc-tricarbonyl to hexahistidine sequence (His-tag) without any changes in biological activity and radiochemical purity of around 98%. Stability analysis revealed that 99mTc-anti-HER2 scFv is stable for at least 24 h in PBS buffer, normal saline, human plasma proteins, and histidine solution.

Molecular and Clinical Portrait of HER2-low Invasive Lobular Carcinomas.

Invasive lobular carcinomas (ILCs) have a low frequency of ERBB2 amplification, therefore restricting the use of conventional anti-HER2 therapies for this histologic special type. Conversely, ILCs with low HER2 overexpression may represent a broader target for the use of emerging antibody drug conjugate therapies targeting HER2, since these treatments have proven effective in HER2-low breast cancers. Very scarce data about HER2-low ILCs have been so far published, although these tumors could have different prevalence and histomolecular specificities compared with invasive breast carcinoma of no special type (IBC-NST). Our aims in that context were to decipher the clinicopathological and molecular features of a large series of HER2-low ILCs. Comparative evaluation of HER2-low prevalence was done based on a retrospective series of 7970 patients from Institut Curie, with either primary invasive lobular (N = 1103) or no special type (N = 6867) invasive carcinoma. Clinicopathological and molecular analyses of HER2-zero, HER2-low, and HER2-positive ILCs were performed on a subgroup of 251 patients who underwent surgery for a primary ILC between 2005 and 2008. The mutational profile of these 251 cases was determined from RNAseq data. Compared with HER2-negative IBC-NSTs, the HER2-negative ILCs were found to display a higher frequency of HER2-zero cases (59.4% vs 53.7%) and a lower frequency of HER2-low (40.6% vs 46.3%) (P < .001). Clinicopathological features associated with HER2-low status (vs HER2-zero) in ILC were older age, postmenopausal status, nonclassic ILC histological types, higher grade, proliferation, and estrogen receptor expression levels. Survival curve analysis showed a significantly lower risk of local recurrence for HER2-low (vs HER2-zero) ILCs, but no association was found between HER2 status and either breast cancer-specific survival or distant metastasis-free interval. ERBB3 was the unique mutated gene exclusively associated with HER2-low ILCs yet being mutated at a low frequency (7.1%) (false discovery rate < 0.05). In conclusion, HER2-low ILCs exhibit their own particularities, both on clinical-pathological and molecular levels. Our findings call for larger multicenter validation studies.

HER2 and PD-L1 Expression in Gastric and Gastroesophageal Junction Cancer: Insights for Combinatorial Targeting Approaches.

Gastric and gastroesophageal junction adenocarcinomas (GA/GEJA) are associated with a poor prognosis, primarily due to late disease diagnosis. Human Epidermal Growth Factor Receptor 2 (HER2) overexpression and programmed death-ligand 1 (PD-L1) expression are important biomarkers for treatment selection in locally advanced unresectable and metastatic GA/GEJA, and there is increasing interest in their role in earlier stages of disease. In this study, we aimed to evaluate HER2 and PD-L1 expression in a curative-intent GA/GEJA cohort to describe their expression patterns and analyze the association between HER2 expression and clinicopathological features. HER2 expression was evaluated in surgical and endoscopic submucosal dissection tumor samples, and PD-L1 was evaluated in HER2-positive cases. The clinical cohort included 107 patients, with 8.4% testing positive for HER2 (seven of whom also exhibited a PD-L1 combined positive score of ≥1. HER2 status was not significantly associated with survival outcomes. A pathologist-guided, region-specific analysis revealed that PD-L1 expression rarely overlaps with HER2-positive tumor areas. While the therapeutic implications of these observations remain unknown, these findings suggest that combination strategies targeting HER2 and PD-L1 might be directed toward distinct tumor subclones. The herein disclosed region-specific biomarker expression patterns may have important therapeutic and prognostic impacts, warranting further evaluation.