HER2-positive Breast Cancer Research Articles

Machine learning models for differential diagnosing HER2-low breast cancer: A radiomics approach.

To develop machine learning models based on preoperative dynamic enhanced magnetic resonance imaging (DCE-MRI) radiomics and to explore their potential prognostic value in the differential diagnosis of human epidermal growth factor receptor 2 (HER2)-low from HER2-positive breast cancer (BC). A total of 233 patients with pathologically confirmed invasive breast cancer admitted to our hospital between January 2018 and December 2022 were included in this retrospective analysis. Of these, 103 cases were diagnosed as HER2-positive and 130 cases were HER2 low-expression BC. The Synthetic Minority Oversampling Technique is employed to address the class imbalance problem. Patients were randomly split into a training set (163 cases) and a validation set (70 cases) in a 7:3 ratio. Radiomics features from DCE-MRI second-phase imaging were extracted. Z-score normalization was used to standardize the radiomics features, and Pearson's correlation coefficient and recursive feature elimination were used to explore the significant features. Prediction models were constructed using 6 machine learning algorithms: logistic regression, random forest, support vector machine, AdaBoost, decision tree, and auto-encoder. Receiver operating characteristic curves were constructed, and predictive models were evaluated according to the area under the curve (AUC), accuracy, sensitivity, and specificity. In the training set, the AUC, accuracy, sensitivity, and specificity of all models were 1.000. However, in the validation set, the auto-encoder model's AUC, accuracy, sensitivity, and specificity were 0.994, 0.976, 0.972, and 0.978, respectively. The remaining models' AUC, accuracy, sensitivity, and specificity were 1.000. The DeLong test showed no statistically significant differences between the machine learning models in the training and validation sets (Z = 0, P = 1). Our study investigated the feasibility of using DCE-MRI-based radiomics features to predict HER2-low BC. Certain radiomics features showed associations with HER2-low BC and may have predictive value. Machine learning prediction models developed using these radiomics features could be beneficial for distinguishing between HER2-low and HER2-positive BC. These noninvasive preoperative models have the potential to assist in clinical decision-making for HER2-low breast cancer, thereby advancing personalized clinical precision.

Additional statin treatment enhances the efficacy of HER2 blockade and improves prognosis in Rac1-high/HER2-positive breast cancer

The prognosis of HER2-positive breast cancer (BC) has improved with the development of anti-HER2 therapies; however, the problem remains that there are still cases where anti-HER2 therapies do not respond well. We found that the expression of SREBF2, a master transcriptional factor in the mevalonate pathway, was correlated with ERBB2 (HER2) expression and a poor prognosis in HER2-positive BC. The target gene expressions of SREBF2 were associated with higher expression of ERBB2 in HER2-positive BC cells. Statins, anti-hypercholesterolemia drugs that inhibit the mevalonate pathway, enhanced the efficacy of HER2-targeting agents with inducing apoptosis in a geranylgeranylation-dependent manner. Mechanistically, statins specifically inhibited membrane localization of Rac1, a target protein of geranylgeranylation, and suppressed the activation of HER2 downstreams AKT and ERK pathways. Consistently, retrospective analysis showed a longer recurrence-free survival in Rac1-high/HER2-positive BC patients treated with HER2-targeting agents with statins than without statins. Our findings thus suggest that Rac1 expression could be used as a biomarker to stratify HER2-positive BC patients that could benefit from dual blockade, i.e., targeting HER2 with inhibition of geranylgeranylation of Rac1 using statins, thereby opening avenues for precision medicine in a new subset of Rac1-high/HER2-positive BC.

Therapeutic response and outcomes with uncommon breast cancer subtypes in the I-SPY trial 2010-2022.

1 Background: Uncommon histologies are over-represented among high-risk breast cancer (BC) and denote an area with limited trial data and of significant unmet medical need. To better understand trial outcomes in this group and identify signals of tumor responsiveness, we report pathologic complete response (pCR) and early event-free survival (EFS) by disease subtype in the I-SPY2 trial. Additionally, the I-SPY2 trial currently utilizes a combination of tumor molecular signature and receptor status to determine response predictive subtype (RPS) first developed from 987 I-SPY2 patients [Wolf et al, Cancer Cell 2022]. We report disease response rates for those who received what is now known to be optimal RPS guided therapy. Methods: The I-SPY2 platform trial tests novel agents given neo-adjuvantly with a chemotherapy backbone in high-risk BC (HER2 positive, triple negative and high molecular risk estrogen receptor positive BC). Histologic images of research biopsies, local biopsy and surgical pathology reports were reviewed centrally by I-SPY pathologists. Receptor subtype distribution and pCR rates were summarized; and EFS was estimated using the Kaplan Meier method. Association between pCR and EFS was evaluated using the Cox proportional hazard model with significance assessed by the log rank test. Results: 144/2118 (7%) of I-SPY2 participants were identified with metaplastic (60), lobular (55), mucinous (9), micropapillary (8), neuroendocrine (4) and other (8) BCS. Tumor receptor status, pCR rate and EFS by tumor type are shown in the Table. For the full cohort, pCR was associated with better EFS (hazard ratio (95% CI): 0.12 (0.02 - 0.88), p = 0.01). Within metaplastic (metapBC) 11/32 (34%) and 5/28 (18%) patients had a pCR with or without checkpoint blockade, respectively. By RPS group, 9 of 18 (50%) (13 metapBC, 3 other, 2 lobular) in the HER2-Immune+ group who received RPS optimized therapy had a pCR. In this group 6/13 (46%) with metapBC had a pCR. In the HER2+ driven RPS groups, pCR rate in the HER+HER2orBasal was 88% (7/8) and 0% (0/3) in the HER2+Luminal. Conclusions: High pCR rates observed in metapBC and other among subsets of often difficult to treat BC subtypes support novel approaches and provide a roadmap for future study of uncommon BCs. Outcomes were improved when therapy matched RPS vulnerabilities. Participants presenting with uncommon BC subtypes will be prospectively identified in the I-SPY2.2 trial to further develop effective approaches for this group. Clinical trial information: NCT01042379 .[Table: see text]

Combination Therapy of Pyrotinib and Metronomic Vinorelbine in HER2+ Advanced Breast Cancer After Trastuzumab Failure (PROVE): A Prospective Phase 2 Study.

Approximately 50-74% of patients with metastatic HER2-positive breast cancer do not respond to trastuzumab, with 75% of treated patients experiencing disease progression within a year. The combination of pyrotinib and capecitabine has showed efficacy in these patients. This study evaluates the efficacy and safety of pyrotinib combined with metronomic vinorelbine for trastuzumab-pretreated HER2-positive advanced breast cancer patients. In this phase 2 trial, patients aged 18-75 years with HER2-positive advanced breast cancer who had previously failed trastuzumab treatment were enrolled to receive pyrotinib 400mg daily in combination with vinorelbine 40mg thrice weekly. The primary endpoint was progression-free survival (PFS), while secondary endpoints included objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety. From October 21, 2019, to January 21, 2022, 36 patients were enrolled and received at least one dose of study treatment. At the cut-off date, 20 experienced disease progression or death. With a median follow-up duration of 35 months, the median PFS was 13.5 months (95% CI: 8.3-18.5). With all patients evaluated, an ORR of 38.9% (95% CI: 23.1-56.5%) and a DCR of 83.3% (95% CI: 67.2-93.6%) were achieved. The median OS was not reached. Grade 3 adverse events (AEs) were observed in 17 patients, with diarrhea being the most common (27.8%), followed by vomiting (8.3%) and stomachache (5.6%). There were no grade 4/5 AEs. Pyrotinib combined with metronomic vinorelbine showed promising efficacy and an acceptable safety profile in HER2-positive advanced breast cancer patients after trastuzumab failure.

Targeted therapies in HER2-positive breast cancer with receptor-redirected Arazyme-linker-Herceptin as a novel fusion protein.

Targeted treatment of different types of cancers through highly expressed cancer cell surface receptors by fusion proteins is an efficient method for cancer therapy. The HER2 receptor is a member of the tyrosine kinase receptors family, which plays a notable role in breast cancer tumor development. About 25-30% of breast cancers overexpress human epidermal growth factor receptor 2 (HER2). In this study, we evaluated the particulars of a designed recombinant protein formed by HER2-specific Mab Herceptin linked with Arazyme on a HER2-overexpressing breast cancer cell line (SKBR3). Arazyme, a metalloprotease produced by Serratia proteamaculans was fused to the variable area of light and heavy chains of the Herceptin. The cytotoxic assay of the Arazyme-linker-Herceptin in the SKBR3 and MDA-MB-468 cells was evaluated by the MTT and flow cytometry techniques. The Caspase‑3 activity determination and adhesion assay were performed to evaluate the antitumor activity of the Arazyme-linker-Herceptin against SKBR3 cells. Furthermore, RT-PCR was used to measure the expression levels of the Bcl-2, Bax, MMP2, MMP9, and RIP3 genes. The Arazyme-linker-Herceptin showed higher cytotoxicity in SKBR3 cells compared to MDA-MB-468 cells. In addition, flow cytometry results revealed that the Arazyme-linker-Herceptin can significantly induce apoptosis in the HER2-overexpressing breast cancer cell line (SKBR3), which was confirmed by Bax upregulation and the decrease in adhesion of tumor cells and MMP2/MMP9. The findings of this study demonstrated that the Arazyme-linker-Herceptin induced apoptosis and decreased metastatic genes in SKBR3 cells; however, further research is required to confirm the effectiveness of the fusion protein.

Targeting ITGβ3 to Overcome Trastuzumab Resistance through Epithelial-Mesenchymal Transition Regulation in HER2-Positive Breast Cancer.

HER2-positive breast cancer, representing 15-20% of all breast cancer cases, often develops resistance to the HER2-targeted therapy trastuzumab. Unfortunately, effective treatments for advanced HER2-positive breast cancer remain scarce. This study aims to investigate the roles of ITGβ3, and Hedgehog signaling in trastuzumab resistance and explore the potential of combining trastuzumab with cilengitide as a therapeutic strategy. Quantitative gene expression analysis was performed to assess the transcription of EMT (epithelial-mesenchymal transition) markers Slug, Snail, Twist2, and Zeb1 in trastuzumab-resistant HER2-positive breast cancer cells. The effects of ITGβ3 and Hedgehog signaling were investigated. Additionally, the combination therapy of trastuzumab and cilengitide was evaluated. Acquired trastuzumab resistance induced the transcription of Slug, Snail, Twist2, and Zeb1, indicating increased EMT. This increased EMT was mediated by ITGB3 and Hedgehog signaling. ITGβ3 regulated both the Hedgehog pathway and EMT, with the latter being independent of the Hedgehog pathway. The combination of trastuzumab and cilengitide showed a synergistic effect, reducing both EMT and Hedgehog pathway activity. Targeting ITGβ3 with cilengitide, combined with trastuzumab, effectively suppresses the Hedgehog pathway and EMT, offering a potential strategy to overcome trastuzumab resistance and improve outcomes for HER2-positive breast cancer patients.

PDL1/HER2-Targeted Lipid-Encapsulated Oxygen Nanobubbles Combined with Photodynamic Therapy for HER2+ Breast Cancer Immunotherapy.

Programmed death (PD) 1/PD ligand 1 (PDL1) inhibitors are immune checkpoint inhibitors (ICIs) that may facilitate HER2-positive breast cancer treatment; however, their clinical efficacy remains elusive. Oxygen-enhanced photodynamic therapy (PDT) increases immunogenic cell death (ICD), providing a promising strategy to render the tumor microenvironment more sensitive to the ICIs. Lipid-encapsulated oxygen nanobubbles (Lipo-NBs-O2) obtained using nanobubbles (NBs) water for oxygen delivery in vivo can facilitate enhanced PDT. Here, dual-receptor targeted Lipo-NBs-O2 (DRT@Lipo-NBs-O2) is prepared by modifying Lipo-NBs-O2 with anti-PDL1 scFv and the fusion protein anti-HER2 scFv-tandem-repeat cytochrome c (anti-HER2-nCytc). Copper phthalocyanine is the photosensitizer (PS). DRT@Lipo-PS-NBs-O2 plus near-infrared irradiation leads to robust ICD induction, increasing DC activation and CD8+ T-cell numbers. Modification with anti-PDL1 scFv improves tumor distribution of DRT@Lipo-PS-NBs-O2 and plays the ICI role, invigorating CD8+ T cells and boosting the effects of immunotherapy. Oxygen supplied through DRT@Lipo-PS-NBs-O2 reduces P-glycoprotein expression. Enhanced PDT and Cytc can cause tumor cell death, thereby reducing the immune burden. Under dual receptor targeting and laser local irradiation, tumor cells become subject to the combination effects of PDT, ICD, ICIs, and apoptosis; this effectively suppresses tumor growth and metastasis. Lipo-NBs-O2 affords a combination of oxygen delivery and multidrug therapy to alleviate HER2-positive breast cancer.

HER2DX Genomic Assay in HER2-Positive Early Breast Cancer Treated with Trastuzumab and Pertuzumab: A Correlative Analysis from the PHERGain Phase II Trial.

The purpose of this study was to assess the predictive capability of HER2DX assay following (neo)adjuvant trastuzumab-pertuzumab (HP)-based therapy in HER2-positive (HER2+) early breast cancer. HER2DX was analyzed in baseline pretreatment tumors from the PHERGain trial. Patients with stage I-IIIA HER2+ early breast cancer were randomized to group A [docetaxel, carboplatin, and HP (TCHP)] and group B (HP ± endocrine therapy). PET response was evaluated after two cycles. Group A received TCHP for six cycles regardless of PET response. Group B continued with HP ± endocrine therapy for six cycles (PET responders) or with TCHP for six cycles (PET nonresponders). The primary objective of this retrospective study was to associate the HER2DX pathologic complete response (pCR) score with pCR. The secondary objective was the association of the HER2DX risk score with 3-year invasive disease-free survival (iDFS). HER2DX was performed on 292 (82.0%) tumors. The overall pCR rate was 38.0%, with pCR rates of 56.4% in group A and 33.8% in group B. In multivariable analysis including treatment and clinicopathologic factors, the HER2DX pCR score (continuous variable) significantly correlated with pCR [OR, 1.29; 95% confidence interval (CI), 1.10-1.54; P < 0.001]. HER2DX-defined pCR-high, -med, and -low groups exhibited pCR rates of 50.4%, 35.8%, and 23.2%, respectively (pCR-high vs. pCR-low OR, 3.27; 95% CI, 1.54-7.09; P < 0.001). In patients with residual disease, the HER2DX high-risk group demonstrated numerically worse 3-year iDFS than the low-risk group (89.8% vs. 100%; HR, 2.70; 95% CI, 0.60-12.18; P = 0.197). HER2DX predicts pCR in the context of neoadjuvant HP-based therapy, regardless of chemotherapy addition, and might identify patients at higher risk of recurrence among patients with residual disease.

ASO Visual Abstract: The Prevalence of Sentinel Lymph Node Positivity and Implications for the Utility of Frozen Section Diagnosis Following Neoadjuvant Systemic Therapy in Patients with Clinically Node-Negative HER2-Positive or Triple-Negative Breast Cancer.

ASO Visual Abstract: The Prevalence of Sentinel Lymph Node Positivity and Implications for the Utility of Frozen Section Diagnosis Following Neoadjuvant Systemic Therapy in Patients with Clinically Node-Negative HER2-Positive or Triple-Negative Breast Cancer.

Enhanced anti-tumor effects by combination of tucatinib and radiation in HER2-overexpressing human cancer cell lines

BackgroundTucatinib (TUC), a HER2-directed tyrosine kinase inhibitor, is the first targeted drug demonstrating intracranial efficacy and significantly prolonged survival in metastatic HER2-positive breast cancer (BC) patients with brain metastases. Current treatments for brain metastases often include radiotherapy, but little is known about the effects of combination treatment with TUC. Therefore, we examined the combined effects of irradiation and TUC in human HER2-overexpressing BC, non-small cell lung cancer (NSCLC), and colorectal cancer (CRC) cell lines. For the latter two, a standard therapy successfully targeting HER2 is yet to be established.MethodsNine HER2-overexpressing (BC: BT474, ZR7530, HCC1954; CRC: LS411N, DLD1, COLO201; NSCLC: DV90, NCI-H1781) and three control cell lines (BC: MCF7, HCC38; NSCLC: NCI-H2030) were examined. WST-1 assay (metabolic activity), BrdU ELISA (proliferation), γH2AX assay (DNA double-strand breaks (DSB), Annexin V assay (apoptosis), and clonogenic assay (clonogenicity) were performed after treatment with TUC and/or irradiation (IR). The relevance of the treatment sequence was analyzed exemplarily.ResultsIn BC, combinatorial treatment with TUC and IR significantly decreased metabolic activity, cell proliferation, clonogenicity and enhanced apoptotis compared to IR alone, whereby cell line-specific differences occurred. In the PI3KCA-mutated HCC1954 cell line, addition of alpelisib (ALP) further decreased clonogenicity. TUC delayed the repair of IR-induced DNA damage but did not induce DSB itself. Investigation of treatment sequence indicated a benefit of IR before TUC versus IR after TUC. Also in CRC and NSCLC, the combination led to a stronger inhibition of metabolic activity, proliferation, and clonogenic survival (only in NSCLC) than IR alone, whereby about 10-fold higher concentrations of TUC had to be applied than in BC to induce significant changes.ConclusionOur data indicate that combination of TUC and IR could be more effective than single treatment strategies for BC. Thereby, treatment sequence seems to be an important factor. The lower sensitivity to TUC in NSCLC and particularly in CRC (compared to BC) implicates, that tumor promotion there might be less HER2-related. Combination with inhibitors of other driver mutations may aid in overcoming partial TUC resistance. These findings are of high relevance to improve long-time prognosis especially in brain-metastasized situations given the intracranial activity of TUC.

Advances from targeted therapy for non-metastatic HER2-positive inflammatory breast cancer.

Among inflammatory breast cancer (IBC) patients, over one-third have HER2-overexpressing (HER2+) tumors. Pathologic complete response (pCR) rates to neoadjuvant targeted and chemotherapy for patients with HER2+ non-metastatic IBC now apporach 60% and favorable long-term survival rates are being reported for those with a pCR. Immune mechanisms contributing to this phenomenon include antibody-mediated immune activation and induction of memory T-cell reponses which may explain the sustained antitumor response seen after discontinuation of targeted therapies.

Peptidylarginine deiminase 3 modulates response to neratinib in HER2 positive breast cancer

Neratinib is a tyrosine kinase inhibitor that is used for the therapy of patients with HER2+ breast tumors. However, despite its clinical benefit, resistance to the drug may arise. Here we have created cellular models of neratinib resistance to investigate the mechanisms underlying such resistance. Chronic neratinib exposure of BT474 human HER2+ breast cancer cells resulted in the selection of several clones resistant to the antiproliferative action of the drug. The clones were characterized biochemically and biologically using a variety of techniques. These clones retained HER2 levels similar to parental cells. Knockdown experiments showed that the neratinib-resistant clones retained oncogenic dependence on HER2. Moreover, the tyrosine phosphorylation status of BT474 and the resistant clones was equally sensitive to neratinib. Transcriptomic and Western analyses showed that peptidylarginine deiminase 3 was overexpressed in the three neratinib-resistant clones studied but was undetectable in BT474 cells. Experiments performed in the neratinib-resistant clones showed that reduction of PADI3 or inhibition of its function restored sensitivity to the antiproliferative action of neratinib. Moreover, overexpression of FLAG-tagged PADI3 in BT474 cells provoked resistance to the antiproliferative action of neratinib. Together, these results uncover a role of PADI3 in the regulation of sensitivity to neratinib in breast cancer cells overexpressing HER2 and open the possibility of using PADI3 inhibitors to fight resistance to neratinib.

Safety evaluation of the trastuzumab biosimilar in Iranian women with HER2-positive breast cancer undergoing adjuvant chemotherapy: a post-marketing surveillance

ABSTRACT Background Trastuzumab is a humanized monoclonal antibody against the human epidermal growth factor receptor 2 (HER2). This post-marketing surveillance evaluates the safety of a trastuzumab biosimilar (AryoTrust), produced by AryoGen Co. Iran in Iranian women with HER2-positive non-metastatic breast cancer (BC). Research Design and Methods The patients who had undergone adjuvant chemotherapy regimens received trastuzumab every 3 weeks for nine cycles. The study started in February 2017 and finished in August 2022. Data regarding safety were collected using booklets and then analyzed. Results A total of 597 women with a mean ±SD age of 48.13 ± 10.18 years underwent 5,313 injection cycles. They received pre-study chemotherapies consisting of anthracyclines, taxanes, both, or other medications in 6.70, 7.20, 82.41, and 2.01% of the cases, respectively. One hundred and thirty-nine patients experienced at least one adverse event (AE). The most common AEs were decreased ejection fraction (EF, 5.7%), peripheral neuropathy (5.36%), and nausea (5.19%). Meningioma was the only life-threatening serious AE. Furthermore, bone pain and infusion-related reactions were the two most common grade three AEs. Nevertheless, the mean EF of patients did not change notably during the study. Conclusions The results demonstrate that this trastuzumab biosimilar is a generally well tolerated and safe treatment for HER2-positive BC. Clinical Trial Registration www.clinicaltrials.gov identifier is NCT06021379.

Olaparib plus trastuzumab in HER2-positive advanced breast cancer patients with germline BRCA1/2 mutations: The OPHELIA phase 2 study

PurposeTo evaluate the efficacy and safety of the combination of olaparib plus trastuzumab in patients with HER2-positive advanced breast cancer (ABC) and germinal BRCA mutations (gBRCAm). MethodsOPHELIA (NCT03931551) was a single-arm, open-label, phase 2 clinical trial. Patients aged ≥18 years diagnosed with HER2-positive ABC with germinal deleterious mutations in BRCA1 or BRCA2 who had received at least one prior systemic regimen for advanced disease were enrolled. Patients received olaparib plus trastuzumab until disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoint was investigator-assessed clinical benefit rate for at least 24 weeks as per RECIST v.1.1. Key secondary endpoints included overall response rate (ORR) and safety profile. ResultsA total of 68 pre-treated HER2-positive ABC patients were screened. Due to slow accrual the trial was stopped after enrolling 5 patients instead of the planned sample size of 20. Four patients achieved clinical benefit (80.0 %, 95 % CI; 28.4–99.5, p < 0.001) and the primary endpoint was met. The ORR was 60.0 % (95 % CI; 14.7–94.7), including one complete response. Four (80.0 %) patients experienced at least one treatment-related treatment-emergent adverse event (TEAE). Most TEAEs were grade 1 or 2. There were no treatment-related deaths and no new safety signals were identified. ConclusionsThis study suggests that the combination of olaparib plus trastuzumab may be effective and safe in pre-treated patients with HER2-positive gBRCAm ABC. This ABC patient population should be further studied and not be pre-emptively excluded from clinical trials of targeted therapy for BRCA1/2-driven cancers.

ASO Visual Abstract: Utility of Axillary Staging in Older Patients with HER2-Positive Breast Cancer.

ASO Visual Abstract: Utility of Axillary Staging in Older Patients with HER2-Positive Breast Cancer.

Preclinical and clinical evaluation through serial colonoscopic evaluation of neratinib-induced diarrhea in HER2-positive breast cancer-A pilot study.

The irreversible pan-HER tyrosine kinase inhibitor neratinib is approved for patients with HER2-positive, early-stage and metastatic breast cancer (BC). Neratinib-associated diarrhea is the most common reason for early discontinuation. Preclinical studies identified mechanisms of neratinib-induced diarrhea and rationale for prophylactic and preventive measures. We studied effects of neratinib on rat intestines and conducted a phase 2 study of colon pathogenesis in patients with HER2-positive BC treated with neratinib (NCT04366713). Colon samples from female albino Wistar rats receiving neratinib or vehicle were examined for histopathological changes. Patients with HER2-positive BC received neratinib 240 mg once daily for up to 1 year. Colonoscopy biopsies were collected at baseline and at Day 28 to identify changes consistent with rat pathologies. Rat colons were markedly altered in appearance, with similar short circuit currents (Isc) and responses to carbachol and forskolin. Mucosal barrier loss and/or significant increase in secretory propensity in neratinib- versus control-treated animals were not seen. Two of four endpoint-evaluable patients presented with mild pathological changes, largely comparable with the rat model. Preclinical evidence supports an inflammatory component of neratinib-induced diarrhea without mucosal barrier function loss. Colonoscopy findings in patients with BC indicate mild or no pathological changes in the colon due to neratinib treatment.

Concurrent radiotherapy with capecitabine and pyrotinib in patients with HER2-positive breast cancer and brain metastases

Concurrent radiotherapy with capecitabine and pyrotinib in patients with HER2-positive breast cancer and brain metastases

Efficacy and safety of first-line regimens for advanced HER2-positive breast cancer: A Bayesian network meta-analysis.

The current standard of care for advanced human epidermal growth factor receptor 2 (HER2)-positive breast cancer is pertuzumab plus trastuzumab and docetaxel as first-line therapy. However, with the development of newer treatment regimens, there is a lack of evidence regarding which is the optimal treatment strategy. The aim of this network meta-analysis was to evaluate the efficacy and safety of first-line regimens for advanced HER2-positive breast cancer by indirect comparisons. A systematic review and Bayesian network meta-analysis were conducted. The PubMed, EMBASE, and Cochrane Library databases were searched for relevant articles published through to December 2023. The hazard ratio (HR) and 95% credible interval (CrI) were used to compare progression-free survival (PFS) between treatments, and the odds ratio and 95% CrI were used to compare the objective response rate (ORR) and safety. Twenty randomized clinical trials that included 15 regimens and 7094 patients were analyzed. Compared with the traditional trastuzumab and docetaxel regimen, PFS was longer on the pyrotinib and trastuzumab plus docetaxel regimen (HR: 0.41, 95% CrI: 0.22-0.75) and the pertuzumab and trastuzumab plus docetaxel regimen (HR: 0.65, 95% CrI: 0.43-0.98). Consistent with the results for PFS, the ORR was better on the pyrotinib and trastuzumab plus docetaxel regimen and the pertuzumab and trastuzumab plus docetaxel regimen than on the traditional trastuzumab and docetaxel regimen. The surface under the cumulative ranking curve indicated that the pyrotinib and trastuzumab plus docetaxel regimen was most likely to rank first in achieving the best PFS and ORR. Comparable results were found for grade ≥3 AE rates of ≥10%. Our results suggest that the pyrotinib and trastuzumab plus docetaxel regimen is most likely to be the optimal first-line therapy for patients with HER2-positive breast cancer.

Anti-HER2 Cancer-Specific mAb, H2Mab-250-hG1, Possesses Higher Complement-Dependent Cytotoxicity than Trastuzumab.

Cancer-specific monoclonal antibodies (CasMabs) that recognize cancer-specific antigens with in vivo antitumor efficacy are innovative therapeutic strategies for minimizing adverse effects. We previously established a cancer-specific anti-human epidermal growth factor receptor 2 (HER2) monoclonal antibody (mAb), H2Mab-250/H2CasMab-2. In flow cytometry and immunohistochemistry, H2Mab-250 reacted with HER2-positive breast cancer cells but did not show reactivity to normal epithelial cells. In contrast, a clinically approved anti-HER2 mAb, trastuzumab, strongly recognizes both breast cancer and normal epithelial cells in flow cytometry. The human IgG1 version of H2Mab-250 (H2Mab-250-hG1) possesses compatible in vivo antitumor effects against breast cancer xenografts to trastuzumab despite the lower affinity and effector activation than trastuzumab in vitro. This study compared the antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cellular cytotoxicity (CDC) between H2Mab-250-hG1 and trastuzumab. Both H2Mab-250-hG1 and trastuzumab showed ADCC activity against HER2-overexpressed Chinese hamster ovary -K1 and breast cancer cell lines (BT-474 and SK-BR-3) in the presence of human natural killer cells. Some tendency was observed where trastuzumab showed a more significant ADCC effect compared to H2Mab-250-hG1. Importantly, H2Mab-250-hG1 exhibited superior CDC activity in these cells compared to trastuzumab. Similar results were obtained in the mouse IgG2a types of both H2Mab-250 and trastuzumab. These results suggest the different contributions of ADCC and CDC activities to the antitumor effects of H2Mab-250-hG1 and trastuzumab, and indicate a future direction for the clinical development of H2Mab-250-hG1 against HER2-positive tumors.

Association Between Radio-pathological Breast Tumor Characteristics and Mammographic Breast Density

Background: Despite mammographic density being a strong indicator of breast cancer risk, it is unclear whether there is association between breast density and certain breast cancer subtypes. This study aimed to investigate the relation between radiologic breast density category and tumor characteristics. Methods: Patients with histologically proven breast cancer who had undergone diagnostic mammography were reviewed retrospectively from 2016 to 2019. The American College of Radiology BI-RADS mammographic density categories were recorded and grouped into low (a and b), and high (c and d). Patient characteristics as well as tumor size, border, pathology, ER, PR, Her2 immunohistochemistry was extracted from the mammography, ultrasonography, and core needle pathology reports. Binary logistic regression model was used to analyze the association between breast density and receptors, molecular subtypes, or tumor features. Results: The present study was comprised of 129 patients, with 7, 47, 41, and 34 patients in the density categories a, b, c, and d, respectively. Patients who had a higher breast density were significantly younger (p=0.001). Those with a lower density were more likely to have HER2, IHC 0 tumors (Odds ratio adjusted for age = 4.9, 95% CI 1.25-18.27, p=0.022). Mammographic density was not related to molecular subtypes and other tumor features. Conclusion: Mammographic dense breast may be associated with Her2 positive breast cancer.