HER2-positive breast cancer and tyrosine kinase inhibitors: the time is now

Comparative analysis of the clinicopathological features and prognostic implications of invasive breast carcinoma of nonspecial type exhibiting HER2-low and HER2-zero expressions

PURPOSE

This retrospectively study aimed to investigate the clinicopathological features, treatments, prognostic differences, and influencing factors between invasive breast carcinoma of nonspecial type (IBC-NST) with low and zero HER2 expressions.

METHODS

Clinical data of patients with IBC-NST exhibiting low and zero HER2 expression were obtained from the Shanghai Jiao Tong University Breast Cancer Database spanning July 2009 to December 2019. The Kaplan-Meier method, log-rank test and Cox regression analyses were performed.

RESULTS

Of the 2071 patients with IBC-NST, 1618 (78.1%) had low HER2 expression and 453 (21.9%) had zero HER2 expression. A higher proportion of patients aged below 40 years, with Ki67 >20%, and with tumor grade III were observed in the HER2-zero group. Higher percentages of estrogen receptor-positive, progesterone receptor-positive, hormone receptor (HR)-positive, and receipt of endocrine therapy were observed in the HER2-low group. The breast cancer-free interval (BCFI) and overall survival (OS) were similar between the groups. In the HR-positive subgroup, no significant differences were observed in the clinical pathological characteristics, treatment types, BCFI, and OS. In the HR-negative subgroup, higher proportions of patients aged over 40 years and patients in the postmenopausal stage were observed in the HER2-low group. Multivariate analysis revealed that the lymph node stage (N2-N3) was an independent risk factor for BCFI and OS regardless of the HER2 status. Meanwhile, HER2-low was an independent risk factor for BCFI in the HR-negative subgroup (hazard ratio, 1.781, 95% confidence interval, 1.061-2.989, P = 0.029).

CONCLUSION

The clinical biological characteristics of HER2-low IBC-NST could be influenced by the HR status. The clinicopathological features and prognosis of HER2-low and HER2-zero IBC-NST were comparable at the same HR status.

Pyrazole-benzimidazole derivatives targeting MCF-7 breast cancer cells as potential anti-proliferative agents. 3D QSAR and In-silico investigations via molecular docking and molecular dynamics simulations

Breast cancer is a complicated type of cancer that mainly occurs in women and poses a global challenge due to its genetic diversity, making accurate diagnosis challenging. The accepted approaches are categorized based on cancer subtype and metastasis level. This study focuses on a predictive drug discovery strategy for compounds that may modulate interaction with HER-2 and EGFR, two important receptors in cancer treatment. We employed a 3D QSAR methodology, complemented by molecular docking, ADMET analysis, and molecular dynamics simulations, to evaluate the antiproliferative effects of pyrazole-benzimidazole derivatives on MCF-7 cells as targeted therapies. External validation confirmed the predictive accuracy of the generated models. The best CoMSIA (Comparative Molecular Similarity Indices Analysis) and CoMFA (Comparative Molecular Field Analysis) models exhibited significant Q2, R2, and RTest2 values, emphasizing the role of electrostatic and hydrophobic fields in inhibiting breast cancer cell growth. These findings provided a foundation for designing and predicting the biological effects of potent inhibitors. Additionally, ADMET analysis was conducted to evaluate the drug-likeness of the newly designed ligands, while the stability of the complexes was confirmed by molecular dynamics simulations, which validate the binding stability of the selected chemicals. MMPBSA, PCA, and FEL investigations provide further support for this assertion, reinforcing the robustness of our conclusions.

Decoding the Epigenome of Breast Cancer

Breast cancer (BC) is the most prevalent malignancy among women, characterized by extensive heterogeneity stemming from molecular and genetic alterations. This review explores the intricate epigenetic landscape of BC, highlighting the significant role of epigenetic modifications-particularly DNA methylation, histone modifications, and the influence of non-coding RNAs-in the initiation, progression, and prognosis of the disease. Epigenetic alterations drive crucial processes, including gene expression regulation, cell differentiation, and tumor microenvironment interactions, contributing to tumorigenesis and metastatic potential. Notably, aberrations in DNA methylation patterns, including global hypomethylation and hypermethylation of CpG islands, have been associated with distinct BC subtypes, with implications for early detection and risk assessment. Furthermore, histone modifications, such as acetylation and methylation, affect cancer cell plasticity and aggressiveness by profoundly influencing chromatin dynamics and gene transcription. Finally, non-coding RNAs contribute by modulating epigenetic machinery and gene expression. Despite advances in our knowledge, clinical application of epigenetic therapies in BC is still challenging, often yielding limited efficacy when used alone. However, combining epi-drugs with established treatments shows promise for enhancing therapeutic outcomes. This review underscores the importance of integrating epigenetic insights into personalized BC treatment strategies, emphasizing the potential of epigenetic biomarkers for improving diagnosis, prognosis, and therapeutic response in affected patients.

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.

Pyrotinib combined with trastuzumab and chemotherapy in the treatment of HER2-positive metastatic breast cancer after the progression of trastuzumab therapy

INTRODUCTION

Retrospective studies have shown that the continuation use of trastuzumab in HER2 positive metastatic breast cancer patients who progressed during treatment with trastuzumab still may have clinical benefits. However, the optimal strategy was still unknown. We conducted this study aiming to explore the efficacy and safety of pyrotinib plus chemotherapy with or without trastuzumab in HER2 positive MBC patients who progressed after previous trastuzumab treatment.

METHODS

This was a real-world retrospective study that enrolled HER2 positive MBC patients previously treated with trastuzumab. Patients were divided into control group (pyrotinib combined with chemotherapy) and combined group (trastuzumab combined with pyrotinib and chemotherapy). The primary endpoint was progression-free survival (PFS), and the secondary endpoints were objective remission rate (ORR), disease control rate (DCR) and safety.

RESULTS

A total of 101 patients were included in the analysis with median follow-up time of 25.5 months (95%CI, 22.5-33.0). The median PFS was 19.1 months (95%CI 10.5-NA, P = 0.039) in combined group and 11.5 months (95%CI 8.1-15.1) in control group. The ORR was 55.6% in the combined group compared with 43.0% in the control group(P = 0.299), and the DCR was 100% compared with 87.7% respectively(P = 0.028). The most common grade 3 or 4 adverse events were diarrhea [7(25.0%)], neutropenia [5(14.3%)] and leukopenia [4(11.4%)] in combined group and diarrhea [3(5.0%)], neutropenia [3(5.0%)] and leukopenia [3(5.0%)] in control group.

CONCLUSIONS

Trastuzumab combined with pyrotinib and chemotherapy showed clinical benefits and acceptable tolerance in HER2-positive MBC patients previously treated with trastuzumab. Thus, these combination regimens may be potential options for such patients.

Systematic review and meta-analysis of artificial intelligence in classifying HER2 status in breast cancer immunohistochemistry

The DESTINY-Breast04 trial has recently demonstrated survival benefits of trastuzumab-deruxtecan (T-DXd) in metastatic breast cancer patients with low Human Epidermal Growth Factor Receptor 2 (HER2) expression. Accurate differentiation of HER2 scores has now become crucial. However, visual immunohistochemistry (IHC) scoring is labour-intensive and prone to high interobserver variability, and artificial intelligence (AI) has emerged as a promising tool in diagnostic medicine. We conducted a diagnostic meta-analysis to evaluate AI's performance in classifying HER2 IHC scores, demonstrating high accuracy in predicting T-DXd eligibility, with a pooled sensitivity of 0.97 [95% CI 0.96-0.98] and specificity of 0.82 [95% CI 0.73-0.88]. Meta-regression revealed better performance with deep learning and patch-based analysis, while performance declined in externally validated and those utilising commercially available algorithms. Our findings indicate that AI holds promising potential in accurately identifying HER2-low patients and excels in distinguishing 2+ and 3+ scores.

Cannabinoids as Promising Inhibitors of HER2-Tyrosine Kinase: A Novel Strategy for Targeting HER2-Positive Ovarian Cancer

Human epidermal growth factor receptor 2 (HER2) is a transmembrane receptor within the ErbB family that plays a pivotal role in the progression of various aggressive cancers. HER2-positive tumors often develop resistance to standard therapies, necessitating the exploration of innovative treatment options. Cannabinoids, bioactive compounds from Cannabis sativa such as cannabidiol (CBD), cannabigerol (CBG), and cannabinol (CBN), have gained attention for their potential anticancer properties. This study evaluates the efficacy of CBD, CBG, and CBN in targeting HER2-positive ovarian cancer through kinase inhibition assays, surface plasmon resonance (SPR), molecular docking, and cell viability assessments. SPR analysis revealed that cannabinoids bind strongly to HER2-tyrosine kinase (HER2-TK), with CBD showing the highest affinity (K D = 6.16 μM), significantly better than afatinib (K D = 26.30 μM), and CBG demonstrating moderate affinity (K D = 17.07 μM). In kinase inhibition assays, CBG was the most potent inhibitor (IC50 = 24.7 nM), followed by CBD (IC50 = 38 nM), suggesting their ability to disrupt HER2-mediated signaling pathways. Molecular docking studies highlighted critical interactions between cannabinoids and essential HER2 residues (Leu796, Thr862, Asp863). In cell viability assays, CBD and CBG effectively inhibited the growth of HER2-positive SKOV3 cells (IC50 = 13.8 μM and 16.6 μM, respectively), comparable to traditional tyrosine kinase inhibitors. These findings underscore the therapeutic potential of cannabinoids, particularly CBD and CBG, as alternative or adjunct therapies for HER2-positive cancers, with the promise of mitigating resistance and adverse effects associated with existing treatments.

Review of the clinical status of cardiotoxicity of HER-2 positive breast cancer targeted therapeutic drugs

Breast cancer is a major health challenge for women worldwide, and human epidermal growth factor receptor 2 (HER-2)-positive breast cancers have a relatively high incidence and are highly aggressive. Targeted therapeutic agents, represented by trastuzumab, have been effective in improving the survival rate of HER-2-positive breast cancer patients. However, in clinical applications, this type of targeted drugs exhibits varying degrees of cardiotoxicity, and the mechanism of their cardiotoxicity is currently unclear. In this paper, we classify them into three categories: monoclonal antibodies (mAbs), small-molecule tyrosine kinase inhibitors (TKIs), and antibody-drug conjugate (ADCs). We list the evidence of cardiotoxicity for various drugs based on current clinical trials and summarize their corresponding epidemiological profiles. We also discuss the regulation of cardiotoxicity from three perspectives: clinical biomarkers of cardiotoxicity, permissive cardiotoxicity, and the current status of cardiotoxicity regulation.

CDK4/6 Inhibitor Resistance in ER+ Breast Cancer

The cyclin-dependent kinases 4 and 6 inhibitors are the mainstay of treatment for patients with hormone receptor-positive and HER2-negative breast cancer. The ability of these drugs to improve the outcome of patients both in the metastatic and the early setting has been largely demonstrated. However, resistance, either de novo or acquired, represents a major clinical challenge. In the past years, efforts have been made to identify biomarkers that might help in a better selection of patients or to unravel the mechanisms leading to resistance in order to develop new therapeutic strategies to overcome it. Alterations of cell cycle-related genes and proteins are among the best characterized markers of resistance, and pathways impacting the cell cycle, including nuclear and growth factor receptors signaling, have been thoroughly investigated. Despite this, to date, cyclin-dependent kinases 4 and 6 inhibitors are administered based only on the hormone receptor and HER2 status of the tumor, and patients progressing on therapy are managed with currently available treatments. Here we summarize present knowledge on the cyclin-dependent kinases 4 and 6 inhibitors' mechanisms of action, efficacy data, and mechanisms of resistance.

Quantum DFT analysis and molecular docking investigation of various potential breast cancer drugs

Breast cancer is among the deadliest cancers worldwide, highlighting the urgent need for effective treatments. This study employs density functional theory (DFT) and molecular docking analyses to evaluate the anti-cancer efficacy and specificity of drug molecules lapatinib, tucatinib, neratinib, anastrozole, and letrozole. DFT analysis provides comprehensive insights into the structural, electronic, optical, and vibrational properties of these drugs, helping to elucidate their molecular stability and reactivity through global reactivity descriptors. Additionally, molecular docking simulations reveal the binding conformations and interaction profiles of these drugs with key breast cancer targets, underscoring their therapeutic potential. Docking results indicate that lapatinib, tucatinib, and neratinib have high binding affinities for HER2, with lapatinib exhibiting the strongest overall binding, particularly with PDK1 (PDB ID: 1UU7), PAK4 (PDB ID: 2X4Z), GSK3 (PDB ID: 1GNG), and HER2 (PDB ID: 2IOK). The stable hydrogen bonding and other interactions observed with lapatinib support its effectiveness in treating HER2-positive breast cancers, tucatinib's selective HER2 binding reduces off-target effects, while neratinib's irreversible binding provides prolonged inhibition, making it useful for overcoming resistance in HER2-positive cases. In contrast, anastrozole and letrozole show lower binding affinities for HER2 and EGFR due to their simpler structures but are potent aromatase inhibitors, making them effective in treating estrogen receptor-positive (ER-positive) breast cancers. In conclusion, DFT and molecular docking studies affirm the suitability of lapatinib, tucatinib, and neratinib for HER2-positive cancers, while anastrozole and letrozole are effective in ER-positive cancers, emphasizing the role of molecular structure and binding affinity in optimizing cancer treatment strategies.

Exploring the therapeutic potential of triterpenoid saponins from Gymnema sylvestre: Mechanistic insights into hepatoprotection, immunomodulation, anticancer activities, molecular docking, and pharmacokinetics

The study comprehensively investigated the therapeutic potential of Gymnema sylvestre triterpenoid saponin extract (GST), encompassing its hepatoprotective, immunomodulatory, and anticancer activities. The study employed a Prednisolone (PRD)-induced immunosuppressed rat model to assess the hepatoprotective and immunomodulatory effects of GST. Using this model, GST was found to modulate haematopoiesis, improving RBC, platelet, and WBC counts, underscoring its potential in hematopoietic homeostasis. Organ atrophy, a hallmark of immunosuppression in spleen, thymus, liver, and kidneys, was reversed with GST treatment, reinforcing its hepatotrophic and organotropic capabilities. Elevated hepatic biomarkers, including alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and lipid peroxidase (LPO), indicative of hepatocellular injury and oxidative stress, were reduced with GST, underscoring its hepatoprotective and antioxidative effects. Additionally, GST restored depleted antioxidants glutathione (GSH) and superoxide dismutase (SOD), highlighting its strong antioxidative capabilities. Molecular insights revealed a downregulation of interleukin-2 (IL-2) and interleukin-4 (IL-4) mRNA in the spleen of immunosuppressed rats, while GST treatment significantly upregulated IL-2 and IL-4 mRNA expression, showcasing its immunomodulatory potential. Increased levels of tumor necrosis factor-α (TNF-α) associated with immune dysregulation were effectively decreased by GST, underscoring its role in modulating inflammatory responses and restoring immune balance. Molecular docking studies indicated strong inhibition of TNF-α by GST compounds. In terms of anticancer activity, GST demonstrated significant cytotoxicity against MCF-7, and MDA-MB-231 (breast cancer cell lines). Notably, GST demonstrated biocompatibility with normal CHO (Chinese hamster ovary cell line) and HUVEC (Human umbilical vein endothelial cells) cell lines. Molecular docking studies indicated strong inhibition of breast cancer proteins HER1 and HER2 (human epidermal growth factor receptors) by GST compounds. Additionally, pharmacokinetics, bioavailability, drug-likeness, and toxicity risk predictions suggest that GST compounds are pharmacologically favourable with no adverse effects.

Feasibility Study of Pyrrolitinib-Based Dual-Target Therapy for Neoadjuvant Treatment of HER2-Positive Breast Cancer Patients

Background

HER2-positive breast cancer is one of the high-risk subtypes of breast cancer for which dual-targeted therapy has become an important treatment option. However, for some patients, complete control of the disease is still not possible and additional treatment is required. Pyrrolitinib, an inhibitor of ALK and MET, has shown promising efficacy in breast cancer treatment. The aim of this study was to investigate the feasibility of adjuvant intensive therapy with pyrrolitinib in the treatment of HER2-positive breast cancer tumors.

Materials and Methods

Twenty-eight patients with HER2-positive breast cancer who were treated at the Breast Surgery Department of the Provincial Hospital of Weihai City, Shandong Province, China, between January 1, 2019, and January 1, 2023, were selected for this study. All of these patients received dual-targeted therapy with the addition of pyrrolitinib therapy adjuvant intensive therapy. We recorded data on the patients' basic information, pathological characteristics, treatment regimens, effects of treatment regimens, and adverse reactions, and statistically analyzed them.

Results

Of the 28 patients with HER2-positive breast cancer, all of them were added to adjuvant intensive therapy with pyrrolitinib. After examination of the samples during treatment, the breast cancer mass had been significantly reduced with the assistance of pyrrolitinib. In addition, no serious adverse reactions were found.

Conclusion

Adjuvant intensification of pyrrolitinib in the treatment of HER2-positive breast cancer tumors is feasible. The results of this study suggest that pyrrolitinib is a safe and effective therapeutic option that can significantly improve the outcome of HER2-positive breast cancer. More studies are needed to further validate this finding.

Targeted HER2-positive cancer therapy using ADAPT6 fused to horseradish peroxidase

Targeted cancer therapy is a promising alternative to the currently established cancer treatments, aiming to selectively kill cancer cells while sparing healthy tissues. Hereby, molecular targeting agents, such as monoclonal antibodies, are used to bind to cancer cell surface markers specifically. Although these agents have shown great clinical success, limitations still remain such as low tumor penetration and off-target effects. To overcome this limitation, novel fusion proteins comprised of the two proteins ADAPT6 and Horseradish Peroxidase (HRP) were engineered. Cancer cell targeting is hereby enabled by the small scaffold protein ADAPT6, engineered to specifically bind to human epidermal growth factor receptor 2 (HER2), a cell surface marker overexpressed in various cancer types, while the enzyme HRP oxidizes the nontoxic prodrug indole-3-acetic acid (IAA) which leads to the formation of free radicals and thereby to cytotoxic effects on cancer cells. The high affinity to HER2, as well as the enzymatic activity of HRP, were still present for the ADAPT6-HRP fusion proteins. Further, in vitro cytotoxicity assay using HER2-positive SKOV-3 cells revealed a clear advantage of the fusion proteins over free HRP by association of the fusion proteins directly to the cancer cells and therefore sustained cell killing. This novel strategy of combining ADAPT6 and HRP represents a promising approach and a viable alternative to antibody conjugation for targeted cancer therapy.

Real-world application of disitamab vedotin (RC48-ADC) in patients with breast cancer with different HER2 expression levels: efficacy and safety analysis

BACKGROUND

Disitamab vedotin (RC48-ADC), an antibody-drug conjugate (ADC), combines specific antibody disitamab with cytotoxicity monomethyl auristatin E to effectively target the human epidermal growth factor receptor 2 (HER2) protein on tumor cells for precise elimination. Recent studies have demonstrated that RC48-ADC offers therapeutic benefits for patients with HER2-positive and HER2-low-expression breast cancer (BC). However, a thorough exploration of its efficacy and safety in real-world settings for patients with metastatic breast cancer (mBC) is currently lacking.

METHODS

This retrospective, multicenter, real-world study included patients with mBC who received RC48-ADC from September 2021 to March 2024. These patients include HER2-positive BC and HER2-low-expression BC. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), restricted mean survival time, objective response rate (ORR), and disease control rate (DCR). Factors affecting efficacy and the occurrence of treatment-related adverse events (TRAE) were evaluated.

RESULTS

The study included a cohort of 89 patients with mBC, with 48 of those being identified as HER2-positive. As of March 2024, 22 deaths were recorded, with an immature median OS. Total PFS varied from 1.0 to 31.2 months, with a median of 5.5 months (95% CI, 4.368-6.632). HER2-positive patients exhibited prolonged PFS compared with HER2-low-expression patients (6.6 months vs 4.1 months, P = .023). The overall ORR stood at 25.8% (95% CI, 0.178-0.358), with higher rates observed in HER2-positive patients compared with HER2-low-expression patients (31.3% vs 19.5%). Similarly, the overall DCR was 78.7% (95% CI, 0.691-0.859), with HER2-positive patients demonstrating superior DCR compared with HER2-low-expression patients (83.3% vs 73.2%). Notably, HER2 expression emerged as the primary determinant of RC48-ADC efficacy. The most prevalent TRAE among all patients included leukopenia (21.3%) and alopecia (20.2%).

CONCLUSION

RC48-ADC showcases promising efficacy and manageable safety in patients with both HER2-positive and HER2-low-expression mBC.

Regulated Pricing Decisions and Diagnostic Test Choices in Personalized Medicine: Navigating the Implications Within Legal Frameworks

Background

The emerging risk of personalized medicine is driving drug manufacturers to seek collaborations with advanced diagnostic firms, aiming to improve detection and treatment outcomes. However, the government's regulated pricing in personalized medicine affects manufacturers' strategic decisions, particularly regarding the selection of diagnostic partners. In this context, this study investigates whether the government should regulate the price of personalized medicine and how the government's regulated pricing decisions affect drug manufacturers' diagnostic test choices.

Methods

A stylized analytical model was developed, employing game-theoretic analysis. Numerical studies are also conducted to validate our results.

Results

The study reveals that in the absence of the government's regulated pricing, drug manufacturers benefit from partnering with high-level diagnostic firms, enhancing consumer surplus and social welfare. However, when the government regulates pricing, the choice of partnering with a high-level diagnostic firm depends on specific conditions, such as low patient sensitivity to treatment failure and a low unit cost coefficient of diagnostic effort. The government's decision to regulate prices is influenced by three key parameters: patients' sensitivity to treatment failure, the unit cost coefficient of the diagnostic test effort, and the proportion of the price of specialized drugs in the regulated pricing.

Conclusions

The findings underscore the importance of legal frameworks in the personalized medicine industry. The absence of the government's regulated pricing incentivizes collaborations with high-level diagnostic firms, enhancing consumer surplus and social welfare. However, government intervention in pricing makes such decisions contingent on specific conditions, requiring nuanced regulatory policies that balance the interests of patients, manufacturers, and diagnostic firms.

A review on tyrosine kinase inhibitors for targeted breast cancer therapy

Breast cancer is a heterogeneous disease with complex molecular pathogenesis. Overexpression of several tyrosine kinase receptors is associated with poor prognosis, therefore, they can be key targets in breast cancer therapy. Tyrosine kinase inhibitors (TKIs) have emerged as leading agents in targeted cancer therapy due to their effectiveness in disrupting key molecular pathways involved in tumor growth. TKIs target various tyrosine kinases, including the human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), Vascular endothelial growth factor receptor (VEGFR), anaplastic lymphoma kinase (ALK), vascular endothelial growth factor receptor (VEGFR)-associated multi-targets, rearranged during transfection (RET), fibroblast growth factor receptor (FGFR), receptor tyrosine kinase-like orphan signal 1 (ROS1), Mitogen-activated protein kinase (MAPK), and tropomyosin receptor kinase (TRK). These drugs target the tyrosine kinase domain of receptor tyrosine kinases and play a vital role in proliferation and migration of breast cancer cells. Several TKIs, including lapatinib, neratinib, and tucatinib, have been developed and are currently used in clinical settings, often in combination with chemotherapy, endocrine therapy, or other targeted agents. TKIs have demonstrated remarkable benefits in enhancing progression-free and overall survival in patients with breast cancer and have become a standard of care for this population. This review provides an overview of TKIs currently being examined in preclinical studies and clinical trials, especially in combination with drugs approved for breast cancer treatment. TKIs have emerged as a promising therapeutic option for patients with breast cancer and hold potential for treating other breast cancer subtypes. The development of new TKIs and their integration into personalized treatment strategies will continue to shape the future of breast cancer therapy.

Interplay of ferroptosis, cuproptosis, and PANoptosis in cancer treatment-induced cardiotoxicity: Mechanisms and therapeutic implications

With the prolonged survival of individuals with cancer, the emergence of cardiovascular diseases (CVD) induced by cancer treatment has become a significant concern, ranking as the second leading cause of death among cancer survivors. This review explores three distinct types of programmed cell death (PCD): ferroptosis, cuproptosis, and PANoptosis, focusing on their roles in chemotherapy-induced cardiotoxicity. While ferroptosis and cuproptosis are triggered by excess iron and copper (Cu), PANoptosis is an inflammatory PCD with features of pyroptosis, apoptosis, and necroptosis. Recent studies reveal intricate connections among these PCD types, emphasizing the interplay between cuproptosis and ferroptosis. Notably, the role of intracellular Cu in promoting ferroptosis through GPX4 is highlighted. Additionally, ROS-induced PANoptosis is influenced by ferroptosis and cuproptosis, suggesting a complex interrelationship. This review provides insights into the molecular mechanisms of these PCD modalities and their distinct contributions to chemotherapy-induced cardiotoxicity. Furthermore, we discuss the potential application of cardioprotective drugs in managing these PCD types. This comprehensive analysis aims to advance the understanding, diagnosis, and therapeutic strategies for cardiotoxicity associated with cancer treatment.

LncRNA ZNF649-AS1 promotes trastuzumab resistance and TAM-dependent PD-L1 expression in breast cancer by regulating EXOC7 alternative splicing

BACKGROUND

Trastuzumab resistance is a serious clinical problem in the treatment of HER2-positive breast cancer (BC). The lncRNA ZNF649-AS1 was previously found to promote HER2-positive BC trastuzumab resistance. The study aims to explore the molecular mechanism of ZNF649-AS1 in HER2-positive BC trastuzumab resistance.

METHODS

Tumor tissue and peripheral blood samples were collected from 20 HER2-positive BC patients with trastuzumab-resistant and non-resistant, respectively. Trastuzumab-resistant BC cell lines SKBR-3-TR and BT474-TR were established. RIP was employed to confirm the binding of ZNF649-AS1, PRPF8 and exocyst complex component 7 (EXOC7). RNA expression of EXOC7-L (Full length of EXOC7) and EXOC7-S (Spliceosome of EXOC7) were detected using agarose gel electrophoresis. Expressions of macrophage markers CD68+ CD206+ were measured by flow cytometry.

RESULTS

ZNF649-AS1 expression was upregulated in HER2-positive BC trastuzumab resistance. ZNF649-AS1 downregulation inhibited trastuzumab resistance in HER2-positive BC. ZNF649-AS1 regulated EXOC7 alternative splicing by binding with PRPF8. EXOC7-S knockdown suppressed trastuzumab resistance and TAM-dependent PD-L1 expression in HER2-positive BC. EXOC7-S overexpression abolished the effects of ZNF649-AS1 knockdown on trastuzumab resistance and TAM-dependent PD-L1 expression in HER2-positive BC.

CONCLUSION

ZNF649-AS1 promoted trastuzumab resistance and TAM-dependent PD-L1 expression in HER2-positive BC via promoting alternative splicing of EXOC7 by PRPF8.

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

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

FCGR3A V158F gene polymorphism and trastuzumab response in HER2-positive breast cancer patients

Breast cancer is considered a multifactorial disease, with genetic factors playing an important role in diagnosis and treatment. FCGR3A encodes the receptor for the Fc portion of immunoglobulin G that has been linked to the trastuzumab response. Our study aimed to investigate the association of FCGR3A-V158F gene polymorphism with breast cancer and to evaluate the impact of FCGR3A-V158F gene polymorphism on trastuzumab response in HER2-positive breast cancer patients. The study was conducted on eighty breast cancer patients who were collected from the Department of Oncology at Ain Shams University Hospitals; in addition, twenty age-matched healthy subjects were taken as a healthy control group. Patients were further sub-classified according to their responses. The study showed that there were no statistically significant differences between patients and controls regarding FCGR3A-V158F gene polymorphism genotypes. However, there was a significant association between the concordance of this polymorphism and the response to trastuzumab therapy among the patient's group. V/V is associated with better treatment response and overall survival (OS) compared to F/V and F/F alleles. Assessment of FCGR3A-V158F gene polymorphism might be useful in making a treatment decision in HER2-positive breast cancer patients.

A case report of interstitial lung disease caused by HER2-positive breast cancer patient receiving two antibody-drug conjugate drugs successively

Background

Comprehensive treatment of breast cancer includes surgery, radiotherapy, chemotherapy, endocrine therapy, targeted therapy and immunotherapy, and the means are extremely rich. In recent years, the antibody-drug conjugates (ADCs) have become one of the significant treatment drugs for patients with human epidermal growth factor receptor 2 (HER2)-positive. ADCs provides new treatment options, and it improves outcomes and quality of life for patients with HER2-positive advanced breast cancer. However, we need to pay special attention to the adverse events (AEs) caused by ADCs, such as gastrointestinal reactions, bone marrow suppression, and interstitial lung disease (ILD), etc. At present, clinicians are in the initial stage of understanding the AEs caused by ADCs, and there is no expert consensus for the treatment on the AEs caused by ADC. For example, ILD caused by ADCs.

Case Description

Here, we reported one case with HER2-positive advanced breast cancer. The patient was treated with ADCs of ARX-788 for third-line treatment, she had ILD. After treatment of ILD, the patient was treated with ADCs of trastuzumab-DM1 (T-DM1) for fourth-line treatment and she had ILD again. After suspension of such drugs, the patient's condition was stable without significant progress over 1 year.

Conclusions

For such patients, how to diagnose and treat them appropriately has become a new challenge for oncologists. Whether other anti-HER2 ADCs can be tried in the later lines is still being cautious. Whether there is a certain relationship between the side effects and efficacy of ADCs, there is no evidence-based data.

Unraveling the future: Innovative design strategies and emerging challenges in HER2-targeted tyrosine kinase inhibitors for cancer therapy

Human epidermal growth factor receptor 2 (HER2) is a transmembrane receptor-like protein with tyrosine kinase activity that plays a vital role in processes such as cell proliferation, differentiation, and angiogenesis. The degree of malignancy of different cancers, notably breast cancer, is strongly associated with HER2 amplification, overexpression, and mutation. Currently, widely used clinical HER2 tyrosine kinase inhibitors (TKIs), such as lapatinib and neratinib, have several drawbacks, including susceptibility to drug resistance caused by HER2 mutations and adverse effects from insufficient HER2 selectivity. To address these issues, it is essential to create innovative HER2 TKIs with enhanced safety, effectiveness against mutations, and high selectivity. Typically, SPH5030 has advanced to phase I clinical trials for its strong suppression of four HER2 mutations. This review discusses the latest research progress in HER2 TKIs, with a focus on the structural optimization process and structure-activity relationship analysis. In particular, this study highlights promising design strategies to address these challenges, providing insightful information and inspiration for future development in this field.

Advances in HER2-Targeted Therapies: From monoclonal antibodies to dual inhibitors developments in cancer treatment

HER2 receptors, overexpressed in certain human cancers, have drawn significant attention in cancer research due to their correlation with poor survival rates. Researchers have developed monoclonal antibodies like Trastuzumab and Pertuzumab against HER2 receptors, which have proven highly beneficial in cancer therapy. Bispecific antibodies like Zanidatamab and antibody-drug conjugates like T-DM1 have been developed to overcome the resistance associated with monotherapy. Small molecules such as Lapatinib, Neratinib, and Pyrotinib were initially developed for treating breast cancer. However, ongoing research is investigating their potential use in other types of cancer, often in combination with other medications. EGFR/HER2 dual-targeted drugs have overcome drug resistance associated with HER2-targeted monotherapy. This comprehensive review covers the structural characteristics of HER2, the HER family signaling pathway mechanism, recent findings regarding HER2 receptor involvement in various cancers, and diverse HER2-targeted therapies. This information provides a comprehensive understanding of HER2-targeted strategies in the evolving field of cancer treatment.

Tyrosine kinase inhibitors in the treatment of leptomeningeal carcinomatosis

Leptomeningeal carcinomatosis (LMC) is a devastating complication of advanced cancers, such as lung cancer and breast cancer, which is usually indicative of a poor prognosis. The current treatments for LMC include palliative care, with others aiming to prolong survival and relieve neurological symptoms. Traditional treatments for LMC include radiotherapy, systemic chemotherapy, and intrathecal injection. Furthermore, the application of molecularly targeted agents, such as antiepidermal growth factor receptor (anti-EGFR), antihuman epidermal growth factor receptor 2 (anti-HER2), and anti-PD-1 monoclonal antibody, have prolonged the survival of LMC patients. Targeted therapy with tyrosine kinase inhibitors has also been proven to be an effective treatment. Tyrosine kinases can be overactive or expressed at high levels in some cancer cells; therefore, the use of tyrosine kinase inhibitors may prevent the activation of tumor-related pathways, preventing cancer cell growth. The EGFR family are cell surface receptors directly related to tumor occurrence with tyrosine kinase activity; it is the most widely used target for tyrosine kinase inhibitors in the treatment of LMC. In this review, we introduced the clinical manifestation and diagnostic criteria of LMC, clarified the treatment mechanism of tyrosine kinase inhibitors for LMC with mutations in EGFR, HER2, or anaplastic lymphoma kinase, reviewed the current application of various generation tyrosine kinase inhibitors in patients with LMC, and discussed new clinical trials and the future directions of tyrosine kinase inhibitor therapy.

Nanotechnology Approaches for Prevention and Treatment of Chemotherapy-Induced Neurotoxicity, Neuropathy, and Cardiomyopathy in Breast and Ovarian Cancer Survivors

Nanotechnology has emerged as a promising approach for the targeted delivery of therapeutic agents while improving their efficacy and safety. As a result, nanomaterial development for the selective targeting of cancers, with the possibility of treating off-target, detrimental sequelae caused by chemotherapy, is an important area of research. Breast and ovarian cancer are among the most common cancer types in women, and chemotherapy is an essential treatment modality for these diseases. However, chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy are common side effects that can affect breast and ovarian cancer survivors quality of life. Therefore, there is an urgent need to develop effective prevention and treatment strategies for these adverse effects. Nanoparticles (NPs) have extreme potential for enhancing therapeutic efficacy but require continued research to elucidate beneficial interventions for women cancer survivors. In short, nanotechnology-based approaches have emerged as promising strategies for preventing and treating chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy. NP-based drug delivery systems and therapeutics have shown potential for reducing the side effects of chemotherapeutics while improving drug efficacy. In this article, the latest nanotechnology approaches and their potential for the prevention and treatment of chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy in breast and ovarian cancer survivors are discussed.

Efficacy and Safety of Neoadjuvant Pyrotinib for Human Epidermal Receptor 2-Positive Breast Cancer: A Meta-Analysis

Neoadjuvant pyrotinib shows the potential to improve treatment response in human epidermal receptor 2 (HER2)-positive breast cancer patients, but relevant meta-analyses are scarce. This meta-analysis intended to explore the efficacy and safety of neoadjuvant pyrotinib for HER2-positive breast cancer patients. Studies comparing the efficacy and safety between HER2-positive breast cancer patients receiving pyrotinib-containing neoadjuvant treatment (pyrotinib group) and those receiving other neoadjuvant treatments (control group), were searched in EMBASE, Web of Science, Cochrane, PubMed, China National Knowledge Infrastructure, Wanfang, and SinoMed until December 2023. Six randomized controlled trials (RCTs) and 4 cohort studies were included. The pyrotinib group and control group contained 540 and 684 patients, respectively. Pathological complete response (pCR) was higher in the pyrotinib group than in the control group [relative risk (RR)=1.93; 95% confidence interval (CI) = 1.63-2.29; P < 0.001]. Similar results were discovered in subgroup analyses of RCTs (RR = 1.89; 95% CI = 1.49-2.40; P < 0.001) and cohort studies (RR = 1.98; 95% CI = 1.55-2.53; P < 0.001). The objective response rate (ORR) was also higher in the pyrotinib group than in the control group (RR = 1.14; 95% CI = 1.07-1.21; P < 0.001). Regarding adverse events, only the incidence of diarrhea was increased in the pyrotinib group versus the control group (RR = 1.97; 95% CI = 1.31-2.96; P = 0.001), while others were not different, including nausea and vomiting, leukopenia, thrombocytopenia, hand-foot syndrome, and alopecia (all P > 0.05). No publication bias existed, and sensitivity analysis suggested the satisfactory robustness of this meta-analysis. In conclusion, compared with other neoadjuvant treatments, pyrotinib-containing neoadjuvant treatment achieves a better treatment response with a good safety profile in HER2-positive breast cancer patients.

Discovery of potent CSK inhibitors through integrated virtual screening and molecular dynamic simulation

Oncogenic overexpression or activation of C-terminal Src kinase (CSK) has been shown to play an important role in triple-negative breast cancer (TNBC) progression, including tumor initiation, growth, metastasis, drug resistance. This revelation has pivoted the focus toward CSK as a potential target for novel treatments. However, until now, there are few inhibitors designed to target the CSK protein. Responding to this, our research has implemented a comprehensive virtual screening protocol. By integrating energy-based screening methods with AI-driven scoring functions, such as Attentive FP, and employing rigorous rescoring methods like Glide docking and molecular mechanics generalized Born surface area (MM/GBSA), we have systematically sought out inhibitors of CSK. This approach led to the discovery of a compound with a potent CSK inhibitory activity, reflected by an IC50 value of 1.6 nM under a homogeneous time-resolved fluorescence (HTRF) bioassay. Subsequently, molecule 2 exhibits strong growth inhibition of MD anderson - metastatic breast (MDA-MB) -231, Hs578T, and SUM159 cells, showing a level of growth inhibition comparable to that observed with dasatinib. Treatment with molecule 2 also induced significant G1 phase accumulation and cell apoptosis. Furthermore, we have explored the explicit binding interactions of the compound with CSK using molecular dynamics simulations, providing valuable insights into its mechanism of action.

Ocular side effects of anticancer agents used in the treatment of gynecologic cancers

The treatment landscape of gynecologic cancers has expanded in recent years to include targeted and immune-based therapies. These therapies often have ocular side effects not seen with conventional chemotherapies, some of which can cause significant visual impairment if not recognized in a timely fashion. Clinicians must know how to appropriately identify, mitigate, and treat these ocular adverse events. Management often involves working with an interdisciplinary team of eye specialists, and it is important to know when to refer patients for specialized care. Proactive identification of eye specialists, especially in rural and community settings where access to care can be limited, may be necessary. Here, we discuss the management of common ocular toxicities seen with novel anticancer agents used to treat gynecologic cancers.

PI3K PROTAC overcomes the lapatinib resistance in PIK3CA-mutant HER2 positive breast cancer

Although anti-HER2 therapy has made significant strides in reducing metastasis and relapse in HER2-positive breast cancer, resistance to agents like trastuzumab, pertuzumab, and lapatinib frequently develops in patients undergoing treatment. Previous studies suggest that the hyperactivation of the PI3K-AKT signaling pathway by PIK3CA/PTEN gene mutations is implicated in HER2 resistance. In this study, we introduce a novel PI3K-p110α Proteolysis TAargeting Chimera (PROTAC) that effectively inhibits the proliferation of breast cancer cells by degrading PI3K-p110α. When tested in two lapatinib-resistant cell lines, JIMT1 and MDA-MB-453, both of which harbor PIK3CA mutations, the PI3K PROTAC notably reduced cell proliferation and induced G1 phase cell cycle arrest. Importantly, even at very low concentrations, PI3K PROTAC restored sensitivity to lapatinib. Furthermore, the efficacy of PI3K PROTAC surpassed that of Alpelisib, a selective PI3K-p110α kinase inhibitor in clinic. The superior performance of PI3K PROTAC was also confirmed in lapatinib-resistant breast cancer xenograft tumors and patient-derived breast cancer organoids (PDOs). In conclusion, this study reveals that the novel PI3K PROTAC we synthesized could serve as an effective agent to overcome lapatinib resistance.

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

BACKGROUND

Tucatinib (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.

METHODS

Nine 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.

RESULTS

In 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.

CONCLUSION

Our 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.

Albumin incorporation into recognising layer of HER2-specific magnetic nanoparticles as a tool for optimal targeting of the acidic tumor microenvironment

Cancer is unquestionably a global healthcare challenge, spurring the exporation of novel treatment approaches. In recent years, nanomaterials have garnered significant interest with the greatest hopes for targeted nanoformulations due to their cell-specific delivery, improved therapeutic efficacy, and reduced systemic toxicity for the organism. The problem of successful clinical translation of nanoparticles may be related to the fact that most in vitro tests are performed at pH values of normal cells and tissues, ranging from 7.2 to 7.4. The extracellular pH values of tumors are characterized by a shift to a more acidic region in the range of 5.6-7.0 and represent a crucial target for enhancing nanoparticle delivery to cancer cells. Here we show the method of non-active protein incorporation into the surface of HER2-targeted nanoparticles to achieve optimal cellular uptake within the pH range of the tumor microenvironment. The method efficacy was confirmed in vitro and in vivo showing the maximum binding of nanoparticles to cells at a pH value 6.4. Namely, fluorescent magnetic nanoparticles, modified with HER2-recognising affibody ZHER2:342, with proven specificity in terms of HER2 recognition (with 62-fold higher cellular uptake compared to control nanoparticles) were designed for targeting cancer cells at slightly acidic pH values. The stabilizing protein, namely, bovine serum albumin, one of the major blood components with widespread availability and biocompatibility, was used for the decoration of the nanoparticle surface to alter the pH response of the targeting magnetic conjugates. The optimally designed nanoparticles showed a bell-shaped dependency of interaction with cancer cells in the pH range of 5.6-8.0 with maximum cellular uptake at pH value 6.4 close to that of the tumor microenvironment. In vivo experiments revealed that after i.v. administration, BSA-decorated nanoparticles exhibited 2 times higher accumulation in tumors compared to magnetic nanoparticles modified with affibody only. Thus, we demonstrated a valid method for enhancing the specificity of targeted nanoparticle delivery to cancer cells without changing the functional components of nanoparticles.

Neratinib impairs function of m6A recognition on AML1-ETO pre-mRNA and induces differentiation of t (8;21) AML cells by targeting HNRNPA3

Acute myeloid leukemia (AML) is frequently linked to genetic abnormalities, with the t (8; 21) translocation, resulting in the production of a fusion oncoprotein AML1-ETO (AE), being a prevalent occurrence. This protein plays a pivotal role in t (8; 21) AML's onset, advancement, and recurrence, making it a therapeutic target. However, the development of drug molecules targeting AML1-ETO are markedly insufficient, especially used in clinical treatment. In this study, it was uncovered that Neratinib could significantly downregulate AML1-ETO protein level, subsequently promoting differentiation of t (8; 21) AML cells. Based on "differentiated active" probes, Neratinib was identified as a functional inhibitor against HNRNPA3 through covalent binding. The further studies demonstrated that HNRNPA3 function as a putative m6A reader responsible for recognizing and regulating the alternative splicing of AML-ETO pre-mRNA. These findings not only contribute to a novel insight to the mechanism governing post-transcriptional modification of AML1-ETO transcript, but also suggest that Neratinib would be promising therapeutic potential for t (8; 21) AML treatment.

Mitochondrial inhibitors: a new horizon in breast cancer therapy

Breast cancer, due to resistance to standard therapies such as endocrine therapy, anti-HER2 therapy and chemotherapy, continues to pose a major health challenge. A growing body of research emphasizes the heterogeneity and plasticity of metabolism in breast cancer. Because differences in subtypes exhibit a bias toward metabolic pathways, targeting mitochondrial inhibitors shows great potential as stand-alone or adjuvant cancer therapies. Multiple therapeutic candidates are currently in various stages of preclinical studies and clinical openings. However, specific inhibitors have been shown to face multiple challenges (e.g., single metabolic therapies, mitochondrial structure and enzymes, etc.), and combining with standard therapies or targeting multiple metabolic pathways may be necessary. In this paper, we review the critical role of mitochondrial metabolic functions, including oxidative phosphorylation (OXPHOS), the tricarboxylic acid cycle, and fatty acid and amino acid metabolism, in metabolic reprogramming of breast cancer cells. In addition, we outline the impact of mitochondrial dysfunction on metabolic pathways in different subtypes of breast cancer and mitochondrial inhibitors targeting different metabolic pathways, aiming to provide additional ideas for the development of mitochondrial inhibitors and to improve the efficacy of existing therapies for breast cancer.

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.

Insights into the Clinical, Biological and Therapeutic Impact of Copy Number Alteration in Cancer

Copy number alterations (CNAs), resulting from the gain or loss of genetic material from as little as 50 base pairs or as big as entire chromosome(s), have been associated with many congenital diseases, de novo syndromes and cancer. It is established that CNAs disturb the dosage of genomic regions including enhancers/promoters, long non-coding RNA and gene(s) among others, ultimately leading to an altered balance of key cellular functions. In cancer, CNAs have been associated with almost all steps of the disease: predisposition, initiation, development, maintenance, response to treatment, resistance, and relapse. Therefore, understanding how specific CNAs contribute to tumourigenesis may provide prognostic insight and ultimately lead to the development of new therapeutic approaches to improve patient outcomes. In this review, we provide a snapshot of what is currently known about CNAs and cancer, incorporating topics regarding their detection, clinical impact, origin, and nature, and discuss the integration of innovative genetic engineering strategies, to highlight the potential for targeting CNAs using novel, dosage-sensitive and less toxic therapies for CNA-driven cancer.

Trastuzumab-functionalized bionic pyrotinib liposomes for targeted therapy of HER2-positive breast cancer

In this study, we prepared a bionic nanosystem of trastuzumab-functionalized SK-BR-3 cell membrane hybrid liposome-coated pyrotinib (Ptb-M-Lip-Her) for the treatment of HER2-positive breast cancer. Transmission electron microscopy, dynamic light scattering, polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting were used to verify the successful preparation of Ptb-M-Lip-Her. In vitro drug release experiments proved that Ptb-M-Lip-Her had a sustained release effect. Cell uptake experiments and in vivo imaging experiments proved that Ptb-M-Lip-Her had good targeting ability to homologous tumor cells (SK-BR-3). The results of cell experiments such as MTT, flow cytometry, immunofluorescence staining and in vivo antitumor experiments showed that Ptb-M-Lip-Her could significantly promote apoptosis and inhibit the proliferation of SK-BR-3 cells. These results clearly indicated that Ptb-M-Lip-Her may be a promising biomimetic nanosystem for targeted therapy of HER2-positive breast cancer.

Artemisia argyi extracts overcome lapatinib resistance via enhancing TMPRSS2 activation in HER2-positive breast cancer

Breast cancer stands as the predominant malignancy and primary cause of cancer-related mortality among females globally. Approximately 25% of breast cancers exhibit HER2 overexpression, imparting a more aggressive tumor phenotype and correlating with poor prognoses. Patients with metastatic breast cancer receiving HER2 tyrosine kinase inhibitors (HER2 TKIs), such as Lapatinib, develop acquired resistance within a year, posing a critical challenge in managing this disease. Here, we explore the potential of Artemisia argyi, a Chinese herbal medicine known for its anti-cancer properties, in mitigating HER2 TKI resistance in breast cancer. Analysis of the Cancer Genome Atlas (TCGA) revealed diminished expression of transmembrane serine protease 2 (TMPRSS2), a subfamily of membrane proteolytic enzymes, in breast cancer patients, correlating with unfavorable outcomes. Intriguingly, lapatinib-responsive patients exhibited higher TMPRSS2 expression. Our study unveiled that the compounds from Artemisia argyi, eriodictyol, and umbelliferone could inhibit the growth of lapatinib-resistant HER2-positive breast cancer cells. Mechanistically, they suppressed HER2 kinase activation by enhancing TMPRSS2 activity. Our findings propose TMPRSS2 as a critical determinant in lapatinib sensitivity, and Artemisia argyi emerges as a potential agent to overcome lapatinib via activating TMPRSS2 in HER2-positive breast cancer. This study not only unravels the molecular mechanisms driving cell death in HER2-positive breast cancer cells induced by Artemisia argyi but also lays the groundwork for developing novel inhibitors to enhance therapy outcomes.

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.

Elucidating molecular mechanisms and therapeutic synergy: irreversible HER2-TKI plus T-Dxd for enhanced anti-HER2 treatment of gastric cancer

BACKGROUND

HER2-targeted therapies have improved the outcomes of HER2-positive gastric cancer (GC), yet resistance remains a challenge. We sought to explore the effects of reversible and irreversible HER2 tyrosine kinase inhibitors (TKIs) alone or in combination with the HER2-targeting antibody drug conjugate trastuzumab deruxtecan (T-Dxd).

METHODS

The effects of HER2-TKIs on HER2 and downstream signaling were evaluated via Western blotting. Proteasomal inhibitors and co-immunoprecipitation assays were performed to explore the role of proteasomal degradation in HER2 expression modulation, and immunofluorescence assays were employed to explore mechanisms of HER2 internalization. The synergistic potential of the irreversible HER2-TKI pyrotinib in combination with T-Dxd was validated using growth and viability assays in anti-HER2-positive GC cell cultures and tumor growth and immunohistochemical staining assays in a mouse xenograft model.

RESULTS

Our study revealed that reversible HER2-TKIs elevated HER2 protein levels, whereas irreversible HER2-TKIs decreased them. Pyrotinib triggered HER2 degradation within the proteasome by promoting ubiquitination and dissociation from HSP90. Furthermore, pyrotinib substantially induced HER2 internalization, which led to improved cellular uptake of T-Dxd. The increased T-Dxd uptake was accompanied by greater efficacy in suppressing the growth of GC cells and enhanced anti-tumor effects in an animal model.

CONCLUSION

In summary, our research reveals the molecular mechanisms of irreversible HER2-TKIs in regulating HER2 protein expression by promoting HER2 internalization. These findings advance our comprehension of targeted therapy for GC and provide a promising therapeutic combination strategy with enhanced efficacy against HER2-positive GC.

The evolvement of breast cancer therapies: What we have done and where all these head off

Although, from a therapeutic standpoint, breast cancer (BC) is considerably well-characterized, it still leaves puzzling spots. The Her-2+/PR+/ER+ BC can benefit from the mainstays of anticancer therapy and immunotherapy and overall have a better prognosis. Triple-negative BC, due to the concomitant absence of Her-2/PR/ER receptors, is more challenging and necessitates different strategies. It has been learned that the mainstay anti-BC therapies were initially designed to demolish as many cancer cells as they possibly could. However, the number of reports on the adverse effects of these mainstay therapies has recently been increasing. It underpins efforts to reshape such therapies into much better and safer forms over time. Moreover, some current findings on the molecular markers, which are target-potential, have also shifted the paradigm from radical-to-local-yet-precise-approach to meet the need for a therapy platform that is less cytotoxic to normal cells yet efficiently kills cancer cells.

Addressing Residual Disease in HER2-Positive and Triple-Negative Breast Cancer: What Is Next?

PURPOSE OF REVIEW

To summarize the treatment strategies for patients with human epidermal growth factor receptor 2 (HER2)-positive disease and triple-negative breast cancer (TNBC) who have residual disease after preoperative systemic therapy.

RECENT FINDINGS

There has been a shift towards neoadjuvant systemic therapy for selected patients with HER2-positive and TNBC. Assessing the tumor's response to therapy provides prognostic information and allows individualization of the postoperative treatment for these patients based on the tumor response to neoadjuvant therapy. Patients with TNBC with residual disease after neoadjuvant therapy can be treated with pembrolizumab, capecitabine, or olaparib. Those with HER2-positive disease are treated with adjuvant trastuzumab emtansine. The treatment of early breast cancer has evolved significantly, and patient outcomes continue to improve. As better treatments are developed, we will need biomarkers to determine which patients may benefit from certain therapies to continue to improve outcomes by right-sizing treatments and limiting toxicities.

Synthesis of novel pyrimido[4,5-b]quinoline derivatives as dual EGFR/HER2 inhibitors as anticancer agents

A series of novel N-aryl-5-aryl-6,7,8,9-tetrahydropyrimido[4,5-b]quinolin-4-amines 4a-4l was synthesized as potential anticancer agents through Dimroth rearrangement reaction of intermediates 3a-3c. Pyrimido[4,5-b]quinolines 4a-4l showed promising activity against the Michigan Cancer Foundation-7 (MCF-7) cell line, compared with lapatinib as the reference drug. Compounds 4d, 4h, 4i, and 4l demonstrated higher cytotoxic activity than lapatinib, with IC50 values of 2.67, 6.82, 4.31, and 1.62 µM, respectively. Compounds 4d, 4i, and 4l showed promising epidermal growth factor receptor (EGFR) inhibition with IC50 values of 0.065, 0.116, and 0.052 µM, respectively. These compounds were subjected to human epidermal growth factor receptor 2 (HER2) inhibition and showed IC50 values of 0.09, 0.164, and 0.055 µM, respectively. Compounds 4d, 4i, and 4l are good candidates as dual EGFR/HER2 inhibitors. The most active compound, 4l, was subjected to cell-cycle analysis and induced cell-cycle arrest at the S phase. Compound 4l induced apoptosis 60-fold compared with control untreated MCF-7 cells. 4l can inhibit cancer metastasis. It reduced MCF-7 cell infiltration and metastasis by 45% compared with control untreated cells.

Why does HER2-positive breast cancer metastasize to the brain and what can we do about it?

Breast cancer is the most frequent malignancy in women. However, in the middle and late stages, some people develop distant metastases, which considerably lower the quality of life and life expectancy. The brain is one of the sites where metastasis frequently happens. According to epidemiological research, brain metastases occur at a late stage in 30-50% of patients with HER2-positive breast cancer, resulting in a poor prognosis. Additionally, few treatments are available for HER2-positive brain metastatic breast cancer, and the mortality rate is remarkable owing to the complexity of the brain's anatomical structure and physiological function. In this review, we described the stages of the brain metastasis of breast cancer, the relationship between the microenvironment and metastatic cancer cells, and the unique molecular and cellular mechanisms. It involves cancer cells migrating, invading, and adhering to the brain; penetrating the blood-brain barrier; interacting with brain cells; and activating signal pathways once inside the brain. Finally, we reviewed current clinically used treatment approaches for brain metastasis in HER2-positive breast cancer; summarized the traditional treatment, targeted treatment, immunotherapy, and other treatment modalities; compared the benefits and drawbacks of each approach; discussed treatment challenges; and emphasized the importance of identifying potential targets to improve patient survival rates and comprehend brain metastasis in breast cancer.

Immunocytochemical markers, molecular testing and digital cytopathology for aspiration cytology of metastatic breast carcinoma

Fine-needle aspiration cytology (FNAC) is a versatile diagnostic procedure uniquely suited for tissue biopsy of breast carcinomas and axillary metastases and/or recurrences. With the expanding treatment options and accompanying theragnostic tests, it is crucial to recognize the developments on ancillary testing and digital cytopathology techniques related to aspiration cytology of metastatic breast carcinoma. In this review, we aim to summarize and update the evidence of immunocytochemistry, for the detection of carcinoma cells (epithelial markers), confirmation of breast primary (breast-specific markers), assessment of surrogate immunostains (hormone receptors, ki-67 proliferative index and HER2) and theragnostic biomarkers, with discussion on potential diagnostic pitfalls, followed by the application of molecular tests, and digital cytopathologic techniques for assessing metastatic breast carcinoma in cytology.

Management of patients with advanced-stage HER2-positive breast cancer: current evidence and future perspectives

Amplification and/or overexpression of ERBB2, the gene encoding HER2, can be found in 15-20% of invasive breast cancers and is associated with an aggressive phenotype and poor clinical outcomes. Relentless research efforts in molecular biology and drug development have led to the implementation of several HER2-targeted therapies, including monoclonal antibodies, tyrosine-kinase inhibitors and antibody-drug conjugates, constituting one of the best examples of bench-to-bedside translation in oncology. Each individual drug class has improved patient outcomes and, importantly, the combinatorial and sequential use of different HER2-targeted therapies has increased cure rates in the early stage disease setting and substantially prolonged survival for patients with advanced-stage disease. In this Review, we describe key steps in the development of the modern paradigm for the treatment of HER2-positive advanced-stage breast cancer, including selecting and sequencing new-generation HER2-targeted therapies, and summarize efficacy and safety outcomes from pivotal studies. We then outline the factors that are currently known to be related to resistance to HER2-targeted therapies, such as HER2 intratumoural heterogeneity, activation of alternative signalling pathways and immune escape mechanisms, as well as potential strategies that might be used in the future to overcome this resistance and further improve patient outcomes.

Overcoming brain-derived therapeutic resistance in HER2+ breast cancer brain metastasis

Brain metastasis of HER2+ breast cancer occurs in about 50% of all women with metastatic HER2+ breast cancer and confers poor prognosis for patients. Despite effective HER2-targeted treatments of peripheral HER2+ breast cancer with Trastuzumab +/-HER2 inhibitors, limited brain permeability renders these treatments inefficient for HER2+ breast cancer brain metastasis (BCBM). The scarcity of suitable patient-derived in-vivo models for HER2+ BCBM has compromised the study of molecular mechanisms that promote growth and therapeutic resistance in brain metastasis. We have generated and characterized new HER2+ BCBM cells (BCBM94) isolated from a patient HER2+ brain metastasis. Repeated hematogenic xenografting of BCBM94 consistently generated BCBM in mice. The clinically used receptor tyrosine kinase inhibitor (RTKi) Lapatinib blocked phosphorylation of all ErbB1-4 receptors and induced the intrinsic apoptosis pathway in BCBM94. Neuregulin-1 (NRG1), a ligand for ErbB3 and ErbB4 that is abundantly expressed in the brain, was able to rescue Lapatinib-induced apoptosis and clonogenic ability in BCBM94 and in HER2+ BT474. ErbB3 was essential to mediate the NRG1-induced survival pathway that involved PI3K-AKT signalling and the phosphorylation of BAD at serine 136 to prevent apoptosis. High throughput RTKi screening identified the brain penetrable Poziotinib as highly potent compound to reduce cell viability in HER2+ BCBM in the presence of NRG1. Successful in-vivo ablation of BCBM94- and BT474-derived HER2+ brain tumors was achieved upon two weeks of treatment with Poziotinib. MRI revealed BCBM remission upon poziotinib, but not with Lapatinib treatment. In conclusion, we have established a new patient-derived HER2+ BCBM in-vivo model and identified Poziotinib as highly efficacious RTKi with excellent brain penetrability that abrogated HER2+ BCBM brain tumors in our mouse models.

Novel immunotherapies for breast cancer: Focus on 2023 findings

Immunotherapy has emerged as a revolutionary approach in cancer therapy, and recent advancements hold significant promise for breast cancer (BCa) management. Employing the patient's immune system to combat BCa has become a focal point in immunotherapeutic investigations. Strategies such as immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT), and targeting the tumor microenvironment (TME) have disclosed encouraging clinical outcomes. ICIs, particularly programmed cell death protein 1 (PD-1)/PD-L1 inhibitors, exhibit efficacy in specific BCa subtypes, including triple-negative BCa (TNBC) and human epidermal growth factor receptor 2 (HER2)-positive cancers. ACT approaches, including tumor-infiltrating lymphocytes (TILs) and chimeric antigen receptor (CAR) T-cell therapy, showed promising clinical outcomes in enhancing tumor recognition and elimination. Targeting the TME through immune agonists and oncolytic viruses signifies a burgeoning field of research. While challenges persist in patient selection, resistance mechanisms, and combination therapy optimization, these novel immunotherapies hold transformative potential for BCa treatment. Continued research and clinical trials are imperative to refine and implement these innovative approaches, paving the way for improved outcomes and revolutionizing the management of BCa. This review provides a concise overview of the latest immunotherapies (2023 studies) in BCa, highlighting their potential and current status.

Targeting the Oxytocin Receptor for Breast Cancer Management: A Niche for Peptide Tracers

Breast cancer is a leading cause of death in women, and its management highly depends on early disease diagnosis and monitoring. This remains challenging due to breast cancer's heterogeneity and a scarcity of specific biomarkers that could predict responses to therapy and enable personalized treatment. This Perspective describes the diagnostic landscape for breast cancer management, molecular strategies targeting receptors overexpressed in tumors, the theranostic potential of the oxytocin receptor (OTR) as an emerging breast cancer target, and the development of OTR-specific optical and nuclear tracers to study, visualize, and treat tumors. A special focus is on the chemistry and pharmacology underpinning OTR tracer development, preclinical in vitro and in vivo studies, challenges, and future directions. The use of peptide-based tracers targeting upregulated receptors in cancer is a highly promising strategy complementing current diagnostics and therapies and providing new opportunities to improve cancer management and patient survival.

ErbB2/HER2 receptor tyrosine kinase regulates human papillomavirus promoter activity

Human papillomaviruses (HPVs) are a major cause of cancer. While surgical intervention remains effective for a majority of HPV-caused cancers, the urgent need for medical treatments targeting HPV-infected cells persists. The pivotal early genes E6 and E7, which are under the control of the viral genome's long control region (LCR), play a crucial role in infection and HPV-induced oncogenesis, as well as immune evasion. In this study, proteomic analysis of endosomes uncovered the co-internalization of ErbB2 receptor tyrosine kinase, also called HER2/neu, with HPV16 particles from the plasma membrane. Although ErbB2 overexpression has been associated with cervical cancer, its influence on HPV infection stages was previously unknown. Therefore, we investigated the role of ErbB2 in HPV infection, focusing on HPV16. Through siRNA-mediated knockdown and pharmacological inhibition studies, we found that HPV16 entry is independent of ErbB2. Instead, our signal transduction and promoter assays unveiled a concentration- and activation-dependent regulatory role of ErbB2 on the HPV16 LCR by supporting viral promoter activity. We also found that ErbB2's nuclear localization signal was not essential for LCR activity, but rather the cellular ErbB2 protein level and activation status that were inhibited by tucatinib and CP-724714. These ErbB2-specific tyrosine kinase inhibitors as well as ErbB2 depletion significantly influenced the downstream Akt and ERK signaling pathways and LCR activity. Experiments encompassing low-risk HPV11 and high-risk HPV18 LCRs uncovered, beyond HPV16, the importance of ErbB2 in the general regulation of the HPV early promoter. Expanding our investigation to directly assess the impact of ErbB2 on viral gene expression, quantitative analysis of E6 and E7 transcript levels in HPV16 and HPV18 transformed cell lines unveiled a noteworthy decrease in oncogene expression following ErbB2 depletion, concomitant with the downregulation of Akt and ERK signaling pathways. In light of these findings, we propose that ErbB2 holds promise as potential target for treating HPV infections and HPV-associated malignancies by silencing viral gene expression.

Sunitinib in Patients With Breast Cancer With FGFR1 or FGFR2 Amplifications or Mutations: Results From the Targeted Agent and Profiling Utilization Registry Study

PURPOSE

The Targeted Agent and Profiling Utilization Registry Study is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer and genomic alterations known to be drug targets. Results from cohorts of patients with metastatic breast cancer (BC) with FGFR1 and FGFR2 alterations treated with sunitinib are reported.

METHODS

Eligible patients had measurable disease, Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and no standard treatment options. Simon's two-stage design was used with a primary end point of disease control (DC), defined as objective response (OR) or stable disease of at least 16 weeks duration (SD16+) according to RECIST v1.1. Secondary end points included OR, progression-free survival, overall survival, duration of response, duration of stable disease, and safety.

RESULTS

Forty patients with BC with FGFR1 (N = 30; amplification only n = 26, mutation only n = 1, both n = 3) or FGFR2 (N = 10; amplification only n = 2, mutation only n = 6, both n = 2) alterations were enrolled. Three patients in the FGFR1 cohort were not evaluable for efficacy; all patients in the FGFR2 cohort were evaluable. For the FGFR1 cohort, two patients with partial response and four with SD16+ were observed for DC and OR rates of 27% (90% CI, 13 to 100) and 7% (95% CI, 1 to 24), respectively. The null hypothesis of 15% DC rate was not rejected (P = .169). No patients achieved DC in the FGFR2 cohort (P = 1.00). Thirteen of the 40 total patients across both cohorts had at least one grade 3-4 adverse event or serious adverse event at least possibly related to sunitinib.

CONCLUSION

Sunitinib did not meet prespecified criteria to declare a signal of antitumor activity in patients with BC with either FGFR1 or FGFR2 alterations. Other treatments and clinical trials should be considered for these patient populations.