HER2 Protein Research Articles

The eugenol functionalized B12N12 and B16N16 cages as potential inhibitors of TNF-α and HER2 receptors

This study aimed to explore the potential of eugenol, B12N12, B16N16, and their complexes against TNF-α (PDB ID: 2AZ5) and HER2 (PDB ID: 3RCD) proteins using Density Functional Theory (DFT) methods, focusing on their spectroscopic, electronic, and thermodynamic parameters as well as the docking of the structures. DFT calculations using the PBE1PBE-D3/6–31 + G** method was performed on the studied structures for geometry optimization, energy calculations, Mulliken population analysis, density of states (DOS), molecular electrostatic potential (MEP), frontier orbital molecules, and UV–Vis and IR spectroscopies. Analysis of the parameters revealed that the adsorption of eugenol via its methoxy group (complexes A and C) over B12N12 and B16N16 cages had the largest negative binding energies, with Ead of –23.09 and −20.49 kcal/mol, respectively. The enthalpy (ΔH) and free energy (ΔG) values for complex A were –23.20 and −9.27 kcal/mol, while for complex C they were −20.54 and −6.79 kcal/mol. The negative values of these parameters indicate that the adsorption process on the cages was exothermic. The quantum molecular descriptor values, alteration of UV–Vis peaks, and IR spectra of the complexes showed higher reactivity compared to pure eugenol. Molecular docking showed that the interaction of eugenol via its methoxy group on the B16N16 cage (complex C) had the best binding affinity and inhibition potential for TNF-α and HER2 in comparison with pure eugenol. The complex had a lower free binding energy value of −5.68 kcal/mol (with TNF-α receptor) and −5.43 kcal/mol (with HER2) compared to pure eugenol, which has energy values of −4.31 and −4.64 kcal/mol, respectively. These findings indicated that the eugenol/B16N16 compound (complex C) is a promising preventive agent against inflammatory diseases and breast cancer.

Abstract A063: What can we learn from a retrospective evaluation of HER2, P53 and P16INK4A protein expression in rare ovarian tumors?

Abstract A063: What can we learn from a retrospective evaluation of HER2, P53 and P16INK4A protein expression in rare ovarian tumors?

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

BackgroundHER2-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).MethodsThe 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.ResultsOur 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.ConclusionIn 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.

Protein structure prediction based on deep learning: HER2 in complex with a covalent inhibitor

HER2 protein overexpression is associated with the malignant degree and poor prognosis of breast cancer. HER2 levels are elevated in 20% of breast tumors. Several covalent tyrosine kinase inhibitors have been found to reduce tumor cell survival and proliferation in vitro and inhibit downstream HER2 signaling. In the field of protein structure prediction, AlphaFold2, which achieved excellent results in CASP14, can periodically predict protein structures with atomic precision in the absence of similar protein structures. In this study, AlphaFold2 was used to predict the monomeric structure of the HER2 protein. This predicted structure was compared to the conformation of HER2 in complex with a covalent inhibitor, allowing for an examination of the conformational changes induced by the inhibitor. By combining the conformational changes of HER2 protein with the docking results of Protein-Ligand Interaction Profiler, other potential binding sites were identified, which could further reveal the mechanism of drug discovery.

Predictive Markers of Treatment Response to Neoadjuvant Systemic Therapy with Dual HER2-Blockade.

In patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer, achievement of pathologic complete response (pCR) is a known prognostic indicator after neoadjuvant systemic therapy (NAST). We investigated the clinicopathological factors associated with pCR in patients with HER2-positive breast cancer treated with dual HER2-blockade. In this retrospective study, 348 patients with HER2-positive breast cancer who received NAST with docetaxel and carboplatin, combined with trastuzumab and pertuzumab (TCHP), were included. Of the 348 patients with HER2 protein expression data, 278 (79.9%) had HER2 immunochemistry (IHC) 3+. Data on tumor-infiltrating lymphocyte (TIL) levels were available for 305 patients, showing a median TIL level of 20% (IQR 5-50), among which 121 (39.7%) had high TIL levels (≥30%). Estrogen receptor (ER) status (77.9% in ER-negative vs. 47.5% in ER-positive; p < 0.001), HER2 protein expression (71.6% in IHC 3+ vs. 34.3% in IHC 2+; p < 0.001), and TIL levels (71.9% in high vs. 57.6% in low; p = 0.011) were significantly associated with the pCR rate. In addition, we observed a significant link between numerical TIL levels (per 10% increment) and the pCR rate. After adjusting other clinicopathologic factors, ER status (low expression [defined as 1-9% expression] or negative), HER2 IHC 3+ and numerical TIL levels (per 10% increment), and high TIL levels (≥30%) were found to be independent predictors of pCR. Notably, in ER-negative breast cancer, the treatment response was excellent, irrespective of HER2 expression and TIL levels. Conversely, in ER-positive cases, low ER expression, HER2 IHC 3+, and numerical TIL levels or high TIL levels emerged as independent predictors of pCR. Our results suggest that ER expression, HER2 protein expression, and TIL levels serve as valuable predictors of the treatment response to neoadjuvant TCHP.

UNRAVELLING THE INTERACTION BETWEEN GARCINISIDONE-A AND HER2 PROTEIN IN BREAST CANCER: A COMPUTATIONAL STUDY

Objective: One substance found in the leaves of Garcinia cowa Roxb that has anticancer properties is garcinisidone-A. The study aims to simulate the docking of garcinisidone-A (Gar-A), molecular dynamics, and predict the ADME by predicting the binding of the HER2 protein in breast cancer cells and developing new drug candidate options for cancer treatment, often starting with computational analysis.&#x0D; Methods: The research method involves computational utilization of pkCSM applications, Gar-A docking simulation with the HER2 protein using Gnina software version 1.0.2, and molecular dynamics conducted with GROMACS 2022.2 and CHARMMGUI applications.&#x0D; Results: Gar-A has a molecular weight of less than 500, a Log P value of greater than 5, a limited amount of water solubility, a low level of skin permeability, good intestinal permeability, and a Convolutional Neural Network (CNN) pose score on the HER2 protein of 0.6178. It also does not readily cross the blood-brain barrier, and total clearance values indicate rapid elimination via other excretory routes or enzyme metabolism. Gar-A is thought to have interactions with HER2. There are hydrogen bond interactions with amino acids Lys753 and Asp863, carbon-hydrogen bonds with amino acids Leu785, Ser783, Thr862, and alkyl bonds with amino acids Leu726, Leu852, and Ile767. The stability of the Gar-A-substrate interaction could have been more evident during 100 ns molecular dynamics simulation.&#x0D; Conclusion: The physicochemical properties of Gar-A align with Lipinski's rule for drug candidates. ADME predictions indicate good intestinal permeability for Gar-A; however, it suggests it cannot penetrate the blood-brain barrier. The docking results reveal that Gar-A has a value close to one which indicates similar action to its natural ligand and molecular dynamics simulations that Gar-A is less stable. The results illustrate that Gar-A has the potential as a breast anticancer.

The phase I/II eNRGy trial: Zenocutuzumab inpatients with cancers harboring NRG1 gene fusions.

Neuregulin 1 (NRG1) fusions are oncogenic drivers that have been detected in non-small-cell lung cancer (NSCLC), pancreatic ductal adenocarcinoma (PDAC) and other solid tumors. NRG1 fusions are rare, occurring in less than 1% of solid tumors. Patients with NRG1 fusion positive (NRG1+) cancer have limited therapeutic options. Zenocutuzumab is a novel, bispecific IgG1 antibody that targets both HER2 and HER3 proteins and inhibits NRG1 binding through a 'Dock & Block®' mechanism of action. Here, we describe the rationale and design of the phase II component of the eNRGy trial, part of the overall, open-label phase I/II, multicenter trial exploring the safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity and antitumor activity of zenocutuzumab in patients with NRG1+ NSCLC, PDAC or other solid tumors.

Integrated multiomic profiling of breast cancer in the Chinese population reveals patient stratification and therapeutic vulnerabilities.

Molecular profiling guides precision treatment of breast cancer; however, Asian patients are underrepresented in publicly available large-scale studies. We established a comprehensive multiomics cohort of 773 Chinese patients with breast cancer and systematically analyzed their genomic, transcriptomic, proteomic, metabolomic, radiomic and digital pathology characteristics. Here we show that compared to breast cancers in white individuals, Asian individuals had more targetable AKT1 mutations. Integrated analysis revealed a higher proportion of HER2-enriched subtype and correspondingly more frequent ERBB2 amplification and higher HER2 protein abundance in the Chinese HR+HER2+ cohort, stressing anti-HER2 therapy for these individuals. Furthermore, comprehensive metabolomic and proteomic analyses revealed ferroptosis as a potential therapeutic target for basal-like tumors. The integration of clinical, transcriptomic, metabolomic, radiomic and pathological features allowed for efficient stratification of patients into groups with varying recurrence risks. Our study provides a public resource and new insights into the biology and ancestry specificity of breast cancer in the Asian population, offering potential for further precision treatment approaches.

The Role of Beclin 1 and HER2 in Colorectal Carcinoma; An Immunohistochemical Study.

This study aimed to evaluate the expression of Beclin 1 and HER2 proteins using immunohistochemistry in CRC tissues compared to colonic adenoma, and to investigate the correlation of their expression with clinicopathological parameters and survival outcomes in CRC patients. The study utilized paraffin-embedded blocks from 17 colonic adenoma and 81 CRC cases. Immunohistochemical analysis was performed to assess the expression of Beclin 1 and HER2 proteins. The cytoplasmic expression of Beclin 1 was significantly higher in CRC tissues compared to adenoma specimens (P=0.051). High Beclin 1 expression was significantly associated with distal colon location (P=0.028). High HER2 cytoplasmic expression was significantly associated with vascular invasion (P=0.05), perineural invasion (P=0.03), and shorter overall survival (P=0.035). The findings suggest that Beclin 1 plays a role in colorectal carcinogenesis, with higher expression observed in CRC cases compared to adenoma cases. Furthermore, HER2 carries poor prognostic impact in CRC cases.

Abstract B002: The impact of mir-4728 on translation and pathway regulation in HER2-amplified breast cancer

Abstract MicroRNAs (miRNAs) are a class of small non-coding RNAs that have been implicated in cancer. Our research focuses on the miRNA mir-4728, which is located in an intron in the HER2 locus. The HER2 locus is amplified in approximately 15% of all breast tumors and is associated with a poor prognosis. Current therapeutic strategies for HER2-positive tumors involve targeted inhibition of the HER2 protein with monoclonal antibodies such as trastuzumab in combination with chemotherapy and surgery. However, if mir-4728 has a function independent of its host gene, targeting the HER2 protein alone may be insufficient. To investigate the role of mir-4728, we utilized antisense oligonucleotides to specifically block mir-4728 in a HER2-amplified breast cancer cell line, while leaving the protein receptor in tact. Polysome fractionation and ribosome profiling revealed that blocking the miRNA resulted in a substantial change in protein translation. We hypothesize that this effect may come as a result of mir-4728 being an indirect regulator of EIF4A, a key factor in the initiation of translation. In addition, we have observed changes in the synthesis of aromatase, a crucial enzyme in estrogen synthesis. These findings suggest that mir-4728 may play a role in the regulation of multiple pathways that contribute to cancer progression. Further investigation into this mechanism may provide valuable insight into the development of new therapeutic strategies for cancer treatment. Citation Format: Völundur Hafstad, Euisuk Han, Helena Persson. The impact of mir-4728 on translation and pathway regulation in HER2-amplified breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B002.

Abstract A005: Ultra-rapid and precise measurement of HER2 copy number alteration by next-generation digital PCR capable of real-time analysis in patients with breast cancer: A multicenter retrospective study

Abstract The HER2 diagnostics is necessary for selection of patients harboring HER2 gene amplification or protein overexpression who will benefit from anti-HER2 therapies in breast cancer. However, HER2 testing is still challenging due to the subjective natures of immunohistochemistry (IHC) and in situ hybridization (ISH), standard methods for determining HER2 status. Thus, a new method is needed to accurately quantify HER2 levels. Here, we developed a clinically reliable HER2 testing method enabling ultra-fast detection of HER2 gene amplification with high accuracy by using the digital real-time PCR (drPCR) system, a potential new diagnostic platform with improved performance by integrating both real-time and digital PCR technologies. For drPCR-based HER2 copy number (CN) measurement, primer-probe sets specific to HER2 gene and a genomic region adjacent to chromosome 17 centromere (CEP17) were designed, and the optimal drPCR condition was determined in clinical breast tumor specimens. To test the clinical validity and standardize procedures of drPCR-based HER2 status evaluation, three independent breast cancer cohorts from different institutions were enrolled, which assigned as a training (SCHU hospital, n = 103) and two validation sets (SNU hospital, n = 170; CNUH hospital, n = 45), and the drPCR assay was compared with current standard HER2 testing methods. In the training cohort, the HER2/CEP17 ratio values from FISH and drPCR tests were highly correlated (r2 = 0.81; P &amp;lt; 0.001), and the drPCR results displayed 98.1% concordance to HER2 status defined by IHC and/or FISH with 92.6% sensitivity and 100% specificity. Eight samples further verified by targeted NGS showed 100% concordance of dPCR to NGS. Consistently, two validation cohorts also showed high concordance of drPCR to IHC and/or ISH results (accuracy = 97.1% and 97.8% in SNU and CNUH cohorts, respectively). The optimal cutoff for HER2 positivity in the drPCR assay was set as a HER2/CEP17 ratio ≥ 1.9 with AUC of 0.963 based on the results from training cohort, and the same cut-off for drPCR was applicable to two independent validation cohorts, supporting the clinical validity of our drPCR-based HER2 assessment. In some discordant cases, low tumor purity (≤ 25%) was observed and microdissection partly improved the drPCR results. The discordance between drPCR and ISH results was also found in marginal HER2+ cases with HER2/CEP17 ratio 2-3, but these cases showed inter-observer variability when re-evaluating the ISH/IHC data due to intratumoral HER2 heterogeneity. Of note, in HER2 IHC3+ cases with negative drPCR results, re-evaluation of IHC using an artificial intelligence (AI)-based HER2 scoring system revised the HER2 IHC 3+ score to 2+, and ISH assessment also confirmed that these cases are indeed HER2-negative, proving the high accuracy of HER2 CN drPCR assay. In conclusion, given the advantages of drPCR-based HER2 assessment with high accuracy, sensitivity, and simplicity, the drPCR assay could be a complementary or alternative method to IHC and ISH to greatly improve current HER2 testing. Citation Format: Jin hyuk Chang, YoonSik Kim, Hee-Joo Choi, Soo Young Park, Ji-Hye Park, Hee-Young Won, Min Ji Song, Da Sol Kim, Hayeon Kim, Sohyeon Yang, Nam Hun Heo, Minsik Song, Seung-Shick Shin, Do Young Lee, Han Suk Ryu, Si-Hyong Jang, Jeong-Yeon Lee. Ultra-rapid and precise measurement of HER2 copy number alteration by next-generation digital PCR capable of real-time analysis in patients with breast cancer: A multicenter retrospective study [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A005.

Abstract IA21: Mechanisms of Resistance to HER2-Targeted Therapies in HER2-positive Breast Cancer

Abstract Recent advancements in HER2-targeted therapies for HER2+ BC have revolutionized patient outcome. Yet, intrinsic and acquired resistance, especially in the advanced setting remains a clinical challenge. In the era of precision oncology, better understanding of these mechanisms of resistance is key to identifying new strategies to overcome resistance and for developing personalized treatment approaches. Our recent studies suggest that a subset of HER2+ BCs, associated with high and homogeneous levels of HER2 gene amplification, protein, and activity, are addicted to HER2 and may therefore benefit from chemotherapy-sparing HER2-targeted regimens. However, even in such tumors, constitutive activation of the PI3K/AKT pathway due to deregulations in the downstream PI3K pathway can lead to resistance. In all HER2+ BCs, failure to achieve a comprehensive blockade of the HER receptor layer is one of the major mechanisms of resistance due to the functional redundancy of the HER receptors and compensatory signaling within the pathway. But, in some cases, effective inhibition of HER receptors might be challenged by molecular masking of the receptors (e.g., MUC4) or by epi/genetic or post-translational alterations in the receptors itself (e.g., HER2 L755S, p95HER2). Indeed, we recently reported that acquisition of HER2 L755S, either alone or together with PIK3CA mutation, and hyperactive EGFR signaling due to acquired EGFR amplification or excess HER ligands are associated with resistance to HER2-targeted therapy, especially tyrosine kinase inhibitors. Likewise, clinically, HER mutations have been reported to be further enriched in the metastatic vs. primary HER2+ tumors. When HER2 does remain sustainably inhibited by HER2-targeted agents, resistance may arise due to the emergence of alternative signaling pathways transmitting compensatory proliferative and survival signals, such as ER, receptor tyrosine kinases, or downstream/intracellular signaling. Further, the emergence of metabolic pathways as alternative pathways of resistance have also been documented. We recently reported the activation of the cholesterol biosynthetic mevalonate (MVA) pathway as an escape mechanism that provides alternative signals through the YAP/TAZ-mTORC1-survivin axis to evade HER2 blockade. This resistance could be overcome using MVA pathway inhibitors (e.g., statins). Additionally, activation of the cell cycle regulatory complex cyclin D1/CDK4 has been shown to be associated with HER2-targeted therapy resistance, which could be exploited as a potential therapeutic vulnerability by using CDK4/6 inhibitors. Finally, response to HER2-targeted therapy could potentially be also modulated by the tumor microenvironment itself, including components of the host immune system and extracellular matrix. Together, a better understanding of the underlying mechanisms of resistance in the context of tumor and host biology, and treatment setup is fundamental to develop new treatment strategies and to guide patient stratification for personalized treatments and improved patient outcomes. Citation Format: Jamunarani Veeraraghavan, Fu-Tien Liao, Lanfang Qin, Tia Gordon, Alekya Raghavan, Caroline Sabotta, Rachel Kaplan, Carolina Gutierrez, C. Kent Osborne, Mothaffar F. Rimawi, Rachel Schiff. Mechanisms of Resistance to HER2-Targeted Therapies in HER2-positive Breast Cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr IA21.

Abstract B030: ABC101-1, a novel microtubule inhibitor antibody-drug conjugate targeting HER2, has potent anti-tumor activity in a breast cancer model

Abstract Background: ABC101-1 is an antibody-drug conjugate (ADC) targeting receptor tyrosine-protein kinase erbB-2, also known as HER2. ABC101-1 consists of a humanized IgG1 monoclonal antibody called trastuzumab conjugated to a microtubulin inhibitor, DM1, through interchain cysteines with a drug-to-antibody ratio (DAR) of 8. Our novel non-cleavable linker platform using maleimide as a connector enabled the construction of homogeneous ABC101-1 with DAR of 8, via a straightforward process resulting in high conjugation yield. Employing non-cleavable linkers may ensure that the cytotoxic drug is delivered stably to tumor cells, enhancing the therapeutic efficacy of ADC. Herein, we describe anti-breast cancer activity through in vitro cytotoxicity and in vivo efficacy, pharmacokinetics, and binding affinity of ABC101-1. Methods: In vitro cytotoxicity of ADC and linker-payload was evaluated by measuring cell viability using Cell Count Kit-8 (CCK8) analysis. In vivo anti-tumor activity was investigated using SKBR3 cell line-derived xenograft (CDX) model. A pharmacokinetic (PK) profile was assessed by performing indirect ELISA to determine concentrations of total mAb in the serum. The binding affinity of ABC101-1 to HER2 protein was assessed using the indirect ELISA measuring the concentrations of total mAb. Results: In this study, ABC101-1 exhibited potent in vitro cytotoxicity with picomolar activity on HER2-positive breast cancer cell line. In the CDX breast cancer model, ABC101-1 led to stronger tumor growth inhibition in both early and late phases than ado-trastuzumab emtansine (DAR 3.5) at the same dose. Also, the favorable pharmacokinetic profile of ABC101-1 was observed, along with the preserved antigen-binding ability upon the conjugation to linker-payload. Conclusions: ABC101-1 displayed preclinical efficacy in in vitro and in vivo studies as well as a favorable PK, thereby suggesting its therapeutic potential as an anti-tumor drug in breast cancer therapy. This study would reveal that our novel linker platform is a promising and efficient strategy to develop effective and homogeneous ADCs with DAR 8. Our finding may support the further pre-clinical evaluation of ABC101-1. Citation Format: Seo Woo Kim, Hana Yu, Geon Ho Lee, Tae Gyu Lim, Minji Jeong, Hyeonjoo Hwang, Jee Eun Moon, Yong Beom Lee, Sung-Ha Jin, Jin Hyun Jeong. ABC101-1, a novel microtubule inhibitor antibody-drug conjugate targeting HER2, has potent anti-tumor activity in a breast cancer model [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B030.

HER2 and PD-L1 immunohistochemistry (IHC) expression, and HER2 genomic alterations: Associations and clinical outcomes for advanced bladder cancer.

538 Background: Bladder cancer (BC) has a relatively high rate of human epidermal growth factor receptor 2 (HER2) alterations. The association between HER2 mutation/amplification, HER2, and PD-L1 immunohistochemistry (IHC) expression and associations with clinical outcomes for advanced bladder cancer (BC) has not been studied. Methods: We retrospectively analyzed BC samples for PD-L1 and HER2 IHC expression and compared HER2 alterations from genomic profiling with the MSK IMPACT platform. HER2 IHC expression was defined as 0, 1+, 2+, 3+, and PD-L1 IHC was the combined tumor and immune cell PD-L1 expression score (CPS). HER2 alteration was defined as either pathogenic mutation and/or amplification. We studied pairwise associations between HER2 alteration, PD-L1, and HER2 IHC expression in all patients and their associations with progression-free survival (PFS) and overall survival (OS) for muscle-invasive bladder cancer (MIBC) pts. Association analyses were performed using the Wilcoxon rank-sum test or Fisher’s exact test. Kaplan-Meier method and Cox proportional hazard models were used for time-to-event analyses. Results: Among 202 pts with HER2 IHC, 188 had MSK IMPACT, and 168 had PD-L1 CPS. The overall incidence of HER2 alteration was 22.3%; 48.2% had CPS ³10, and HER2 IHC distribution was 0:18.8%, 1+:29.7%, 2+:33.7%, and 3+:17.8%. The CPS score was inversely associated with HER2 IHC expression (p&lt;0.001). No association was noted between CPS score and HER2 alteration (p=0.735). HER2 altered tumors were strongly correlated with high-level HER2 IHC expression (p&lt;0.001). However, 41% (n=14/34) of HER2 IHC 3+ samples did not have HER2 alterations, and 17% (n=7/36) of HER2 altered samples had HER2 IHC expression of 0. In patients with MIBC, HER2 alteration and HER2 IHC expression (0/1+ vs. 2+/3+) were not associated with PFS (p=0.5 and p=0.4, respectively) or OS for MIBC pts (p=0.84 and p=0.94, respectively). A higher PD-L1 CPS score (&gt;=10 vs &lt;10) was associated with improved PFS for MIBC pts (p=0.03). Conclusions: Our study is the first to describe an inverse correlation between HER2 IHC expression and PD-L1 CPS score. Furthermore, HER2 IHC overexpression is strongly associated with HER2 amplification, but a subset of patients with high HER2 protein expression are potentially missed by genomic profiling alone. HER2 expression by IHC or HER2 genomic alteration is not a prognostic marker for MIBC pts in this cohort. This data provides the foundation for further HER2-directed advanced BC studies. [Table: see text]

Mitochondrial HER2 stimulates respiration and promotes tumorigenicity.

Amplification of HER2, a receptor tyrosine kinase and a breast cancer-linked oncogene, is associated with aggressive disease. HER2 protein is localised mostly at the cell membrane, but a fraction translocates to mitochondria. Whether and how mitochondrial HER2 contributes to tumorigenicity is currently unknown. We enriched the mitochondrial (mt-)HER2 fraction in breast cancer cells using an N-terminal mitochondrial targeting sequence and analysed how this manipulation impacts bioenergetics and tumorigenic properties. The role of the tyrosine kinase activity of mt-HER2 was assessed in wild type, kinase-dead (K753M) and kinase-enhanced (V659E) mtHER2 constructs. We document that mt-HER2 associates with the oxidative phosphorylation system, stimulates bioenergetics and promotes larger respiratory supercomplexes. mt-HER2 enhances proliferation and invasiveness invitro and tumour growth and metastatic potential invivo, in a kinase activity-dependent manner. On the other hand, constitutively active mt-HER2 provokes excessive mitochondria ROS generation, sensitises to cell death, and restricts growth of primary tumours, suggesting that regulation of HER2 activity in mitochondria is required for the maximal pro-tumorigenic effect. mt-HER2 promotes tumorigenicity by supporting bioenergetics and optimal redox balance.

HER2 aptamer-conjugated iron oxide nanoparticles with PDMAEMA-b-PMPC coating for breast cancer cell identification.

Aim: To synthesize HER2 aptamer-conjugated iron oxide nanoparticles with a coating of poly(2-(dimethylamino) ethyl methacrylate)-poly(2-methacryloyloxyethylphosphorylcholine) block copolymer (IONPPPs). Methods: Characterization covered molecular structure, chemical composition, thermal stability, magnetic characteristics, aptamer interaction, crystalline nature and microscopic features. Subsequent investigations focused on IONPPPs for in vitro cancer cell identification. Results: Results demonstrated high biocompatibility of the diblock copolymer with no significant toxicity up to 150μg/ml. The facile coating process yielded the IONPP complex, featuring a 13.27nm metal core and a 3.10nm polymer coating. Functionalized with a HER2-targeting DNA aptamer, IONPPP enhanced recognition in HER2-amplified SKBR3 cells via magnetization separation. Conclusion: These findings underscore IONPPP's potential in cancer research and clinical applications, showcasing diagnostic efficacy and HER2 protein targeting in a proof-of-concept approach.

Current and Future Biomarkers in Esophagogastric Adenocarcinoma.

Biomarker-based therapies have shown improved patient outcomes across various cancer types. The purpose of this review to summarize our knowledge of current and future biomarkers in esophagogastric adenocarcinoma (EGA). In this publication, we will review current standard biomarkers in patients with upper GI cancers. We will also discuss novel biomarkers that are under investigations and their associated therapies that are currently in clinical trials. EGAa are a group of heterogeneous diseases, both anatomically and molecularly. There are several established biomarkers (HER2, PD-L1, microsattelite instability or mismatch repair protein expression) that allow for individualized treatments for patients with these cancers. There are also several emerging biomarkers for EGA, some of which have clinically relevant associated therapies. Claudin 18.2 is the furthest along among these. Anti-claudin antibody, zolbetuximab, improved overall survival in biomarker select patients with advanced GEA in two phase 3 studies. Other novel biomarkers, such as FGFR2b and DKN01, are also in the process of validation, and treatments based on the presence of these biomarkers are currently in clinical studies. Ongoing efforts to identify novel biomarkers in EGA have led to enhanced subclassification of upper GI cancers. These advances, coupled with the strategic application of targeted therapies and immunotherapy when appropriate, hold promise to further improve patients outcomes.

Anchoring of hyaluronan glycocalyx to CD44 reduces sensitivity of HER2-positive gastric cancer cells to trastuzumab.

Trastuzumab is widely used in human epidermal growth factor receptor 2 (HER2)-positive gastric cancer (GC) therapy, but ubiquitous resistance limits its clinical application. In this study, we first showed that CD44 antigen is a significant predictor of overall survival for patients with HER2-positive GC. Next, we found that CD44 could be co-immunoprecipitated and co-localized with HER2 on the membrane of GC cells. By analyzing the interaction between CD44 and HER2, we identified that CD44 could upregulate HER2 protein by inhibiting its proteasome degradation. Notably, the overexpression of CD44 could decrease the sensitivity of HER2-positive GC cells to trastuzumab. Further mechanistic study showed that CD44 upregulation could induce its ligand, hyaluronan (HA), to deposit on the cancer cell surface, resulting in covering up the binding sites of trastuzumab to HER2. Removing the HA glycocalyx restored sensitivity of the cells to trastuzumab. Collectively, our findings suggested a role for CD44 in regulating trastuzumab sensitivity and provided novel insights into HER2-targeted therapy.

Label-free and early detection of HER2 breast cancer biomarker based on UiO-66-NH2 modified gold chip (Au/UiO-66-NH2) using surface plasmon resonance technique

Breast cancer is one of the leading causes of cancer death for women worldwide. This cancer occurs when the breast cells grow abnormally and spread uncontrolled. Although there are several treatments, including chemotherapy, radiation, and surgery in a clinical setting to cure cancer, these treatments cannot provide a 100 % success rate in eliminating cancer, mainly due to the late diagnosis of the disease. Thus, early detection is the key to provide better breast cancer treatment and a higher chance for survival. Herein, simple and sensitive biosensor by combining the emerging multifunctional materials of metal-organic frameworks (MOFs) with a label-free surface plasmon resonance (SPR) instrument was developed. Two types of stable Zirconium (Zr)-based MOFs, namely Zr benzene dicarboxylic acid (Zr-BDC or UiO-66) and Zr 2-amino-benzene dicarboxylic acid (Zr-BDC-NH2 or UiO-66-NH2) were synthesized using the solvothermal method. X-ray diffractometer (XRD) and fourier transform infra red (FTIR) confirmed the formation of the prepared UiO-66 and UiO-66-NH2. The electron microscopy and nitrogen adsorption desorption isotherm characterization reveal that the MOFs have a cubic crystal structure with a high surface area of 672.4 m2/g for UiO-66 and 286.1 m2/g for UiO-66-NH2. The MOFs are then functionalized on the SPR gold (Au) chip surface to serve as a matrix of Human Epidermal Growth Factor Receptor 2(HER2) antibody receptors. Interestingly, the functionalized SPR biosensors could detect the HER2 protein target with high sensitivity in the ng/mL range and a remarkable detection limit, which is 0.457 ng/mL for UiO-66-NH2. This LOD value is significantly lower than clinical concentrations of HER2 proteins in human blood (∼15 ng/mL), which indicate that the biosensor can offer the capability of early detection test.

A homogeneous electrochemical sensing platform based on DNAzyme walker for accurate detection of breast cancer exosomes

Exosomes generated from tumors contain a range of bioactive molecules, making them attractive and trustworthy non-invasive biomarkers for prognostic monitoring and adjuvant diagnosis of malignancies. Here, a homogeneous portable electrochemical sensing platform based on DNAzyme-induced DNA walker and enzyme-catalyzed amplification strategies has been created to accurately identify exosomes from breast cancer. The aptasensor induced enzymatic cleavage through dual probe recognition, and the continuous movement of the DNA walker achieves the cleavage of a large number of substrate strands. This causes a significant number of enzyme-containing DNA fragments to be released, and the enzyme that is released catalyzes the production of hydrogen peroxide (H2O2) by oxidizing excess glucose. The hydrogen peroxide (H2O2) underwent a redox reaction using a screen-printed carbon electrode (SPCE), and the detection of exosome can be achieved by reading current signal changes. The detection limit of the sensor is 3.63 × 104 particles/mL SK-BR-3 exosomes. This method improved the accuracy of detection by double recognition of MUC1 protein and HER2 protein on breast cancer exosomes and avoided cumbersome electrode modification steps. In addition, clinical serum samples can be analyzed using the constructed electrochemical sensor to separate patients with breast cancer from healthy volunteers as well as patients with various tumors. It is anticipated that the current work will give an effective tool for the accurate detection of breast cancer exosomes because it presents a novel technique for doing so in HER2-positive breast cancer.