HER2 In Cancer Research Articles

Dual-Targeting of the HER2 Cancer Receptor with an Antibody-Directed Enzyme and a Nanobody-Guided MMAE Prodrug Scaffold.

Antibody-enzyme conjugates have shown potential as tissue-specific prodrug activators by antibody-directed enzyme prodrug therapy (ADEPT), but the approach met challenges clinically due to systemic drug release. Here, we report a novel dual-targeting ADEPT system (DuADEPT) which is based on active cancer receptor targeting of both a trastuzumab-sialidase conjugate (Tz-Sia) and a highly potent sialidase-activated monomethyl auristatin E (MMAE) prodrug scaffold. The scaffold is based on a four-way junction of the artificial nucleic acid analog acyclic (L)-threoninol nucleic acid ((L)-aTNA) which at the ends of its four arms carries one nanobody targeting HER2 and three copies of the prodrug. Dual-targeting of the constructs to two proximal epitopes of HER2 was shown by flow cytometry, and a dual-targeted enzymatic drug release assay revealed cytotoxicity upon prodrug activation specifically for HER2-positive cancer cells. The specific delivery and activation of prodrugs in this way could potentially be used to decrease systemic side effects and increase drug efficacy, and utilization of Tz-Sia provides an opportunity to combine the local chemotherapeutic effect of the DuADEPT with an anticancer immune response.

The Performance and Clinical Applicability of HER2 Digital Image Analysis in Breast Cancer: A Systematic Review.

This systematic review aims to address the research gap in the performance of computational algorithms for the digital image analysis of HER2 images in clinical settings. While numerous studies have explored various aspects of these algorithms, there is a lack of comprehensive evaluation regarding their effectiveness in real-world clinical applications. We conducted a search of the Web of Science and PubMed databases for studies published from 31 December 2013 to 30 June 2024, focusing on performance effectiveness and components such as dataset size, diversity and source, ground truth, annotation, and validation methods. The study was registered with PROSPERO (CRD42024525404). Key questions guiding this review include the following: How effective are current computational algorithms at detecting HER2 status in digital images? What are the common validation methods and dataset characteristics used in these studies? Is there standardization of algorithm evaluations of clinical applications that can improve the clinical utility and reliability of computational tools for HER2 detection in digital image analysis? We identified 6833 publications, with 25 meeting the inclusion criteria. The accuracy rate with clinical datasets varied from 84.19% to 97.9%. The highest accuracy was achieved on the publicly available Warwick dataset at 98.8% in synthesized datasets. Only 12% of studies used separate datasets for external validation; 64% of studies used a combination of accuracy, precision, recall, and F1 as a set of performance measures. Despite the high accuracy rates reported in these studies, there is a notable absence of direct evidence supporting their clinical application. To facilitate the integration of these technologies into clinical practice, there is an urgent need to address real-world challenges and overreliance on internal validation. Standardizing study designs on real clinical datasets can enhance the reliability and clinical applicability of computational algorithms in improving the detection of HER2 cancer.

A Comprehensive Review of HER2 in Cancer Biology and Therapeutics.

Human epidermal growth factor receptor 2 (HER2), a targetable transmembrane glycoprotein receptor of the epidermal growth factor receptor (EGFR) family, plays a crucial role in cell proliferation, survival, and differentiation. Aberrant HER2 signaling is implicated in various cancers, particularly in breast and gastric cancers, where HER2 overexpression or amplification correlates with aggressive tumor behavior and poor prognosis. HER2-activating mutations contribute to accelerated tumorigenesis and metastasis. This review provides an overview of HER2 biology, signaling pathways, mechanisms of dysregulation, and diagnostic approaches, as well as therapeutic strategies targeting HER2 in cancer. Understanding the intricate details of HER2 regulation is essential for developing effective targeted therapies and improving patient outcomes.

Abstract 2111: Impact of HER2 Expression on trastuzumab deruxtecan(T-DXd) efficacy

Abstract Background: T-DXd is an FDA-approved anti-HER2 Antibody Drug Conjugate (ADC), which has shown clinical efficacy in breast cancers with either overexpression or low-level expression of HER2. The benefit of T-DXd across the spectrum of HER2 expression has called into question the relevance of HER2 expression level as relevant parameter for T-DXd sensitivity. We sought to experimentally address the relevance of HER2 expression level upon the degree of T-DXd response. Methods: A series of isogenic models was generated that expressed different levels of surface HER2 using a doxycycline-inducible promoter. These were analyzed for impact of differential expression level upon T-DXd internalization and drug response. Human breast cancer samples were analyzed for HER2 expression levels and association with clinical response to T-DXd under an IRB approved protocol. Results: Induction of different levels of HER2 at specified doxycycline concentrations was verified in multiple models using immunoblotting and FACS. These different levels appeared to correspond to clinical breast cancer immunohistochemistry (IHC) scoring levels to 0, 1+, 2+, and 3+. The models were analyzed for T-DXd response and showed increasing levels of HER2 led to increase lysosomal uptake of T-DXd (p<0.0001). Moreover, elevation of HER2 levels led to lower concentrations of T-DXd needed to suppress tumor growth. Analyses of the effects of increasing levels of HER2 upon xenograft response to T-DXd are ongoing. Finally, retrospective analyses of a cohort of 50 breast cancer patients treated with T-DXd revealed that higher levels of HER2 corresponded to longer time on treatment (time to progression). Conclusion: We observe a consistent relationship between elevated expression of HER2 and breast cancer response to T-DXd. The findings highlight the relevance of HER2 expression level as a biomarker of T-DXd response and support the potential value of therapeutic strategies that can induce HER2 surface expression levels to enhance response. Citation Format: Wanyi Chen, Joshua Drago, Avantika Gupta, Bo Liu, Sarat Chandarlapaty. Impact of HER2 Expression on trastuzumab deruxtecan(T-DXd) efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2111.

Radiomic Characteristics of Different T<sub>1</sub> Breast Cancer Biotypes

Background: Breast cancer (BC) occupies a leading position among my oncological diseases detected in women. Identification and search for predictors of malignant neoplasms using radiation and molecular genetic methods of research allows timely diagnosis and treatment, which improves the prognosis for breast cancer. Purpose: To identify a correlation between the molecular subtype of a breast cancer tumor at an early clinical stage and the patterns of the mammographic method. Methods: A prospective, single-center study of 363 patients diagnosed with breast cancer followed up during 2021. X-ray mammography in two projections, ultrasound-guided trephine biopsy for histological verification, and immunohistochemical (IHC) analysis to determine molecular subtypes were performed. Results: There were statistically significant differences in age between subtypes luminal A, luminal BHER2+ (p < 0.001) and triple negative (p = 0.037), luminal B, luminal BHER2+ (p = 0.001) and triple negative (p = 0.046), luminal BHER2+ and nonluminal HER2+ (p = 0.002), between nonluminal HER2+ and triple negative subtype (p = 0.034). When comparing the structure of radiological density, statistically significant differences were revealed between the subgroups luminal B, luminal BHER2+ (p = 0.010) and triple negative (p = 0.010), between luminal A and triple negative subtypes (p = 0.010). When comparing the leading mammographic symptom (p < 0.001), radiological contours of the formation (p < 0.001), the density of pathological changes (p < 0.001), the size, the newly detected pathological process (p < 0.001) statistically significant differences were also found in the subgroups. A division into groups according to the size of pathological changes within the biotypes was noted, where the aggressive phenotypes of the triple negative subtype (p = 0.001), non-luminal HER2+ (p = 0.02) and luminal B (p = 0.02), in contrast to luminal A, were manifested by a greater extent. the maximum linear size of the tumor. A symptom of nipple retraction (p = 0.048) was described, which was not characteristic of triple negative and non-luminal HER2 cancer. Conclusions: Visualization features of differences in the radiological manifestation of breast cancer of different biological subtypes up to 20 mm can be predictors of molecular subtypes. Pathological verification and IHC study remain a mandatory study, but it may be necessary to conduct an X-ray histological correlation before starting treatment and, if obvious discrepancies are detected, repeat the IHC analysis from the surgical material.

Targeting HER2 and FGFR-positive cancer cells with a bispecific cytotoxic conjugate combining anti-HER2 Affibody and FGF2

Breast cancer remains a significant global health challenge, necessitating the development of effective targeted therapies. This study aimed to create bispecific targeting molecules against HER2 and FGFR1, two receptors known to play crucial roles in breast cancer progression. By combining the high-affinity Affibody ZHER2:2891 and a modified, stable form of fibroblast growth factor 2 (FGF2), we successfully generated bispecific proteins capable of simultaneously recognizing HER2 and FGFR1. Two variants were designed: AfHER2-sFGF2 with a shorter linker and AfHER2-lFGF2 with a longer linker between the HER2 and FGFR1-recognizing proteins. Both proteins exhibited selective binding to HER2 and FGFR1, with AfHER2-lFGF2 demonstrating simultaneous binding to both receptors. AfHER2-lFGF2 exhibited superior internalization compared to FGF2 in FGFR-positive cells and significantly increased internalization compared to AfHER2 in HER2-positive cells. To enhance their therapeutic potential, highly potent cytotoxic agent MMAE was conjugated to the targeting proteins, resulting in protein-drug conjugates. The bispecific AfHER2-lFGF2-vcMMAE conjugate demonstrated exceptional cytotoxic activity against HER2-positive, FGFR-positive, and dual-positive cancer cell lines that was significantly higher compared to monospecific conjugates. These data indicate the beneficial effect of simultaneous targeting of HER2 and FGFR1 in precise anticancer medicine and contribute valuable insights into the design and potential of bispecific targeting molecules for breast cancer treatment.

Integrating extracellular vesicle and circulating cell-free DNA analysis using a single plasma aliquot improves the detection of HER2 positivity in breast cancer patients.

Multi-analyte liquid biopsies represent an emerging opportunity for non-invasive cancer assessment. We developed ONCE (One Aliquot for Circulating Elements), an approach for the isolation of extracellular vesicles (EV) and cell-free DNA (cfDNA) from a single aliquot of blood. We assessed ONCE performance to classify HER2-positive early-stage breast cancer (BrCa) patients by combining EV-associated RNA (EV-RNA) and cfDNA signals on n=64 healthy donors (HD) and non-metastatic BrCa patients. Specifically, we isolated EV-enriched samples by a charge-based (CB) method and investigated EV-RNA and cfDNA by next-generation sequencing (NGS) and by digital droplet PCR (ddPCR). Sequencing of cfDNA and EV-RNA from HER2- and HER2+ patients demonstrated concordance with in situ molecular analyses of matched tissues. Combined analysis of the two circulating analytes by ddPCR showed increased sensitivity in ERBB2/HER2 detection compared to single nucleic acid components. Multi-analyte liquid biopsy prediction performance was comparable to tissue-based sequencing results from TCGA. Also, imaging flow cytometry analysis revealed HER2 protein on the surface of EV isolated from the HER2+ BrCa plasma, thus corroborating the potential relevance of studying EV as companion analyte to cfDNA. This data confirms the relevance of combining cfDNA and EV-RNA for HER2 cancer assessment and supports ONCE as a valuable tool for multi-analytes liquid biopsies' clinical implementation.

Abstract P6-12-05: The role of endothelial-specific AXL and its associated signaling pathways in the tumor microenvironment

Abstract Most breast cancer deaths result from the development of metastases. The complex tumor microenvironment provides signals that can instruct both breast cancer cells to invade and tumor blood vessels to be leaky, hence supporting metastasis. We identified the receptor tyrosine kinase (RTK) AXL to be essential for metastasis. Genetic ablation of Axl in mouse models of HER2+ breast cancer, either globally or specifically in mammary epithelial cells, blunts metastasis but not primary tumor growth. We found that Axl expressed in tumor cells contributes to the remodeling of the tumor microenvironment, including immune cell recruitment and abnormal blood vessels. Hence, AXL in epithelial cells promotes cell invasion and shapes a pro-metastatic microenvironment that would be poorly responding to treatments such as immunotherapy. While AXL is known to be expressed on endothelial cells, its endothelial function has yet to be clearly defined. This project aims to address the hypothesis that AXL expressed on endothelial cells promotes processes that lead to abnormal blood vessel formation to promote metastasis. To address this hypothesis, we first studied the specific intracellular interactions between two RTKs, AXL and the known pro-angiogenic receptor VEGFR. Our preliminary analyses indicates that GAS6 can not only induce the phosphorylation of the permeability marker eNOS on its own but can also potentiate the VEGF’s response. The index of linearity of the endothelial tight junctions upon GAS6 stimulation show increased permeability of the endothelial cells. To further characterize the signaling pathways controlled by these receptors, we plan to perform a phosphoproteomics screen. We will focus on studying the AXL+VEGFR phosphoproteome and define the signaling pathways that impact vascular permeability. The most interesting candidate(s) will be studied in the context of mouse tumor models. In parallel, we are generating a conditional deletion of Axl in endothelial cells by crossing Axlfx/fx mice with Pdgfb:iCreER animals. With this, we will study the specific endothelial effects of Axl in vivo, specifically with vessel permeability and retinal angiogenesis assays. Multiple anti-angiogenic therapies for cancer failed in the clinic highlighting the need for new strategies to target endothelial cells in cancer. This project will provide essential information on the role of endothelial specific AXL, in the context of the HER2 breast cancer, and of its downstream effectors. With more specific targets, anti-angiogenic therapies could decrease their off-target effects and increase their efficacy in the clinic. This project has the potential to uncover therapeutic targets that could reduce the metastatic burden in breast cancer patients, and therefore better the prognostic for the HER2 cancer subtype. Citation Format: Andréane Lalonde, Jean-François Côté. The role of endothelial-specific AXL and its associated signaling pathways in the tumor microenvironment [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-12-05.

NEDD9 Overexpression Causes Hyperproliferation of Luminal Cells and Cooperates with HER2 Oncogene in Tumor Initiation: A Novel Prognostic Marker in Breast Cancer.

HER2 overexpression occurs in 10-20% of breast cancer patients. HER2+ tumors are characterized by an increase in Ki67, early relapse, and increased metastasis. Little is known about the factors influencing early stages of HER2- tumorigenesis and diagnostic markers. Previously, it was shown that the deletion of NEDD9 in mouse models of HER2 cancer interferes with tumor growth, but the role of NEDD9 upregulation is currently unexplored. We report that NEDD9 is overexpressed in a significant subset of HER2+ breast cancers and correlates with a limited response to anti-HER2 therapy. To investigate the mechanisms through which NEDD9 influences HER2-dependent tumorigenesis, we generated MMTV-Cre-NEDD9 transgenic mice. The analysis of mammary glands shows extensive ductal epithelium hyperplasia, increased branching, and terminal end bud expansion. The addition of oncogene Erbb2 (neu) leads to the earlier development of early hyperplastic benign lesions (~16 weeks), with a significantly shorter latency than the control mice. Similarly, NEDD9 upregulation in MCF10A-derived acini leads to hyperplasia-like DCIS. This phenotype is associated with activation of ERK1/2 and AURKA kinases, leading to an increased proliferation of luminal cells. These findings indicate that NEDD9 is setting permissive conditions for HER2-induced tumorigenesis, thus identifying this protein as a potential diagnostic marker for early detection.

Expression of RBMS3 in Breast Cancer Progression.

The aim of the study was to evaluate the localization and intensity of RNA-binding motif single-stranded-interacting protein 3 (RBMS3) expression in clinical material using immunohistochemical (IHC) reactions in cases of ductal breast cancer (in vivo), and to determine the level of RBMS3 expression at both the protein and mRNA levels in breast cancer cell lines (in vitro). Moreover, the data obtained in the in vivo and in vitro studies were correlated with the clinicopathological profiles of the patients. Material for the IHC studies comprised 490 invasive ductal carcinoma (IDC) cases and 26 mastopathy tissues. Western blot and RT-qPCR were performed on four breast cancer cell lines (MCF-7, BT-474, SK-BR-3 and MDA-MB-231) and the HME1-hTERT (Me16C) normal immortalized breast epithelial cell line (control). The Kaplan-Meier plotter tool was employed to analyze the predictive value of overall survival of RBMS3 expression at the mRNA level. Cytoplasmatic RBMS3 IHC expression was observed in breast cancer cells and stromal cells. The statistical analysis revealed a significantly decreased RBMS3 expression in the cancer specimens when compared with the mastopathy tissues (p < 0.001). An increased expression of RBMS3 was corelated with HER2(+) cancer specimens (p < 0.05) and ER(-) cancer specimens (p < 0.05). In addition, a statistically significant higher expression of RBMS3 was observed in cancer stromal cells in comparison to the control and cancer cells (p < 0.0001). The statistical analysis demonstrated a significantly higher expression of RBMS3 mRNA in the SK-BR-3 cell line compared with all other cell lines (p < 0.05). A positive correlation was revealed between the expression of RBMS3, at both the mRNA and protein levels, and longer overall survival. The differences in the expression of RBMS3 in cancer cells (both in vivo and in vitro) and the stroma of breast cancer with regard to the molecular status of the tumor may indicate that RBMS3 could be a potential novel target for the development of personalized methods of treatment. RBMS3 can be an indicator of longer overall survival for potential use in breast cancer diagnostic process.

Anticancer activity of Indonesian Melia azedarach L.: Phyto-chemistry, in vitro and in silico studies

This study describes the isolation of bioactive compounds and their in vitro anticancer activities from Melia azedarach L leaves from Karanglor, Karangan, Karanganom Klaten, Central Java-Indonesia. Isolated and characterised were the phenolics, kaempferol 7-O-rutinoside 1 and 4-methoxyresorcinol 3, The anticancer activity of the crude methanol extract of M. azedarach against a number cell lines (LNCaP, MDA-MB-231, and MCF-7) was found to be moderate; kaempferol derivatives were notable for their antiproliferative activities. Computational analysis, including molecular docking simulations and molecular dynamic studies, were used to investigate the feasibility of radiolabelled versions of 1 and 3 as theranostic agents targeting tyrosine kinase-type cell surface receptor HER2 in cancer - the iodinated derivatives 2 and 4, respectively, were used in this investigation as surrogates. The corresponding radioiodinated 2 and 4 were found to have high binding affinities of 10.1 and 5.7 kcal/mol, respectively, and have a good stability on the receptor.

Assessment of the HER2, PDL1 and oxidative stress levels at the menopausal status of newly diagnosed breast cancer patients

Objective: This study aimed to estimate the levels of HER2, PD-L1 and oxidative stress in newly diagnosed breast cancer patients. Also, to estimate the probability of using HER2 and PD-L1 as a predictive marker on the occurrence of breast cancer in addition to study the effect of menopausal status at the level of HER2, PD-L1, oxidative stress and breast cancer risk factor.&#x0D; Methods: This study included 125 newly diagnosed breast cancer patients (53 premenopausal and 72 postmenopausal) from Oncology and Nuclear Medicine Hospital in Mosul, Iraq, and 100 apparently healthy women as a control group (44 premenopausal and 56 postmenopausal), during the period from Jan. 2021 to Jun. 2021. The ages of patients and control are matched, and it is ranged from 30-60 years.&#x0D; In this study we estimate the level of Human Epidermal Growth Factor Receptor 2 (HER2), Programmed Death -Ligand 1(PD-L1), total antioxidant capacity (T-AOC), arylesterase activity, uric acid level, malondialdehyde (MDA) level, peroxidase activity, lactoperoxidase activity and iron level at breast cancer patients and control.&#x0D; Results: The results show that there is a significant elevation in the level of HER2, PD-L1, malondialdehyde, peroxidase, lactoperoxidase and iron, and a significant decrease in the level of T-AOC, arylesterase and uric acid in the serum of breast cancer patients (pre and postmenopausal) compared with the control group (pre and postmenopausal).&#x0D; Also, increase the level of HER2 and oxidative stress at postmenopausal status for the control and patient groups. while PD-L1 level does not affect by menopausal status for both control and patient groups.&#x0D; Conclusion: The level of HER2, PD-L1, and oxidative stress was significantly increased in newly diagnosed breast cancer patients compared with the control group at the same menopausal status. Increase breast cancer risk factor at the postmenopausal status.

Gasdermin B over-expression modulates HER2-targeted therapy resistance by inducing protective autophagy through Rab7 activation.

BackgroundGasdermin B (GSDMB) over-expression promotes poor prognosis and aggressive behavior in HER2 breast cancer by increasing resistance to therapy. Decoding the molecular mechanism of GSDMB-mediated drug resistance is crucial to identify novel effective targeted treatments for HER2/GSDMB aggressive tumors.MethodsDifferent in vitro approaches (immunoblot, qRT-PCR, flow cytometry, proteomic analysis, immunoprecipitation, and confocal/electron microscopy) were performed in HER2 breast and gastroesophageal carcinoma cell models. Results were then validated using in vivo preclinical animal models and analyzing human breast and gastric cancer samples.ResultsGSDMB up-regulation renders HER2 cancer cells more resistant to anti-HER2 agents by promoting protective autophagy. Accordingly, the combination of lapatinib with the autophagy inhibitor chloroquine increases the therapeutic response of GSDMB-positive cancers in vitro and in zebrafish and mice tumor xenograft in vivo models. Mechanistically, GSDMB N-terminal domain interacts with the key components of the autophagy machinery LC3B and Rab7, facilitating the Rab7 activation during pro-survival autophagy in response to anti-HER2 therapies. Finally, we validated these results in clinical samples where GSDMB/Rab7/LC3B co-expression associates significantly with relapse in HER2 breast and gastric cancers.ConclusionOur findings uncover for the first time a functional link between GSDMB over-expression and protective autophagy in response to HER2-targeted therapies. GSDMB behaves like an autophagy adaptor and plays a pivotal role in modulating autophagosome maturation through Rab7 activation. Finally, our results provide a new and accessible therapeutic approach for HER2/GSDMB + cancers with adverse clinical outcome.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13046-022-02497-w.

Prognostic Value of HER2 in Metastatic Colorectal Cancer: A Single Institutional Experience

Prognostic Value of HER2 in Metastatic Colorectal Cancer: A Single Institutional Experience

HER 2 in Gastric Cancer in Albania as a New Therapeutic Alternative

Background: Gastric cancer (GC) is the fourth most common cancer in Albania. Gastric cancer has a 5-year survival rate as low as 30%. The expression of HER2 in gastric cancer has brought a new alternative treatment for patients. Materials and method: 192 patients were analyzed retrospectively, with primary GCs for HER2 overexpression by IHC and Dual SISH in equivocal cases. This was compared with the results of HER2 in gastric patients in surgical specimens and endoscopic biopsies and there is a correlation between gender, age, stage, and type of the histopathologic gastric cancer diagnosis. Results: Examinations were made by immunohistochemistry for HER2 in 73.4% (141 cases) of surgical specimens and 26.5% of endoscopic biopsies: 18.4% (26 cases) and 15.7% (8 cases) were HER2 3+, respectively. HER2 overexpression (3+) was detected in 17.7% (34 cases). HER2 Equivocal (2+) was detected in 24.5% (47 cases). 17.8%, 14%, and 4.7% were respectively intestinal type, diffuse, signet ring, and the rest adenocarcinoma NOS. GC prevailed in the group aged 61-70 yrs. (31.70%), followed by 51-60 yrs. (25%), 22.9% in 71-80-yrs. 20 cases analyzed by SISH, showed HER2 amplification in 40% (8cases). Economical restrictions and problems with the preanalytical phase made it impossible to evaluate by SISH all 20 cases. Conclusion: 17.7% of Albanian patients with primary GC were HER2-positive on IHC. There is no difference in biopsy and surgical specimen results. Economic restrictions can influence the results.

Abstract 4124: Clinical outcomes in women with metastatic HER2-Low breast cancer in the real world

Abstract Background: The development of novel anti-HER2 drugs opens new treatment options for patients with breast cancers, including women with lower expression of HER2. The aim of this study was to compare the clinical outcomes of HER2-low and HER2-zero metastatic breast cancer in the real world. Methods: Female patients diagnosed with metastatic breast cancer and low HER2 expression or HER2-zero expression between 2010 and 2017, and who received systematic therapy, were identified from the National Cancer Database (NCDB). The National Cancer Data Base (NCDB) is a nationwide oncology outcomes database that collects information on approximately 70% of all new invasive cancer diagnoses in the United States.HER2-Low was defined as IHC1+ or 2+/ISH negative, whereas HER2-zero was defined as IHC0, based on the American Society of Clinical Oncology/College of American Pathologists guideline. The primary outcome was overall survival(OS). A multivariable Cox regression model was performed to estimate hazard ratios (HR), adjusting for age, race/ethnicity, education, comorbidities, grade, presence of visceral metastasis, and the type of cancer center where patients were treated. The analyses were stratified by hormone receptor status. Results: A total of 22817 of 33417 (68%) were HER2-low and 10600 (32%) were HER2-zero. Hormone receptor-positivity was in 19988 (88%) with HER2-low tumors, whereas 8112 (77%) was in HER2-zero tumors. Women with HER2-low tumors had significantly longer overall survival (OS) than did with Her2-zero tumors in both hormone receptor-positive (median OS 39.0 months vs 37.1 months; adjusted HR: 0.93, 95%CI (0.90-0.96), p&amp;lt;0.001) and hormone receptor-negative groups (median OS 15.8 months vs 14.1 months; adjusted HR: 0.92 95%CI (0.86-0.98), p=0.005). Conclusion: In the metastatic setting, HER2-low tumors have a better survival than HER2-zero tumors, irrespective of hormone receptor status. Specific therapies, such as trastuzmab deruxtecan, have activity in women with HER-low breast cancers and additional therapeutics for HER-2 low should be sought. Citation Format: Changchuan Jiang, Stuthi Perimbeti, Lei Deng, Charles L. Shapiro, Shipra Gandhi. Clinical outcomes in women with metastatic HER2-Low breast cancer in the real world [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4124.

Abstract 527: A streamlined workflow for liquid biopsy extraction and highplex digital PCR analysis using the Maxwell® RSC system and 6-color Crystal Digital PCR™

Abstract Circulating cell free DNA (cfDNA) extracted from liquid biopsy samples have become established sample types for characterizing oncology targets. Currently, there are several extraction protocols and genomic platforms for researchers to select when interrogating genetic information. The focus of this work was to identify a flexible method for sample extraction that seamlessly integrates into a straightforward and sensitive genetic analysis workflow from plasma samples. Here, we present a workflow combining the Maxwell RSC system for automated cfDNA extraction and Crystal Digital PCR on the naica system for ultrasensitive high-plex detection from liquid biopsy samples of EGFR mutations in non-small cell lung cancer (NSCLC) and PIK3CA mutations and HER2 amplification in breast cancer. By bridging sample extraction with the Maxwell RSC system and high-plex digital PCR with the 6-color naica® system, we detected with high sensitivity and precision 32 common and rare somatic EGFR mutations in exons 18, 19, 20, and 21, representing more than 90% of EGFR mutations described in NSCLC. Furthermore, following the same extraction and sample testing workflow, we simultaneously detected a set of PIK3CA mutations and HER2 amplification from cfDNA samples. This proof-of-concept workflow creates the foundation for further development of streamlined sample-to-answer protocols that will better assist cancer researchers across the biomarker testing landscape. Citation Format: Cécile Jovelet, Myrtille Remy, Mylene Menanteau, Doug White, Douglas Horejsh, Allison Mallory. A streamlined workflow for liquid biopsy extraction and highplex digital PCR analysis using the Maxwell® RSC system and 6-color Crystal Digital PCR™ [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 527.

Evaluation of KISS1 Receptor Gene Expression in Egyptian Female Patients with Breast Cancer.

Objective:Breast cancer is the second most common cancer in the world. Many metastasis suppressor genes were identified, including the KISS1 gene which encodes for a 145 amino acid protein (kisspeptin-145), which undergoes proteolytic cleavage resulting in kisspeptin-14, -13 and -10. All of these proteins can activate KISS1 receptor (KISS1R). The role of KP/KISS1R signaling in breast cancer remains controversial. The present study aimed to measure mRNA gene expression of KISS1 receptor in healthy and cancerous breast tissue and to evaluate the association of its level with the available molecular subtypes and the traditional clinico-pathological variables. Methods:The study was done on 41 operable primary breast cancer patients. Biopsies from both tumor tissue and surrounding healthy mammary tissue were taken from all patients. KISS1R mRNA expression level was measured using a quantitative real time PCR. Results:KISS1R mRNA expression was significantly higher in stage III patients compared to stage II patients. At a cut-off value for KISS1R mRNA expression of 1.75, stage II was discriminated from stage III. A significant positive correlation was found between KISS1R mRNA expression and tumor size as well as lymph nodes metastasis. KISS1R mRNA was highly expressed in ER negative cases compared to ER positive ones, and in PR negative cases compared to PR positive ones. There was a statistically significant difference in KISS1R mRNA expression levels and different molecular subtypes being over-expressed in HER2 and triple negative cancer cases. Conclusion:This study supports other studies suggesting that KISS1/KISS1R may not be acting as a metastasis suppressor in breast cancer. KISS1R mRNA is over expressed in advanced stages of breast cancer and hence it can be used as a prognostic marker for aggressiveness of breast cancer. Also being over expressed in triple negative patients, KISS1R could represent a promising therapeutic target in triple negative cases.

Recent advances in biosensor devices for HER-2 cancer biomarker detection

The human epidermal growth factor receptor 2 (HER-2) protein is a member of the epidermal growth factor receptor (EGFR or ErbB) family and is a transmembrane tyrosine kinase receptor. HER-2 is highly regulated in ovarian, lung, gastric, oral, and breast cancers. The low specificity, complexity, expensiveness and the lack of sensitivity are essential restrictions in traditional diagnosis methods such as FISH, immunohistochemistry and PCR and these disadvantages led to the need for more studies on alternative methods. Biosensor technology has greatly affected the quality of human life owing to its features including, sensitivity, specificity, and rapid diagnosis and monitoring of different patient diseases. In this review article, we examine various biosensors, considering that they have been categorized based on the transducers used including piezoelectric biosensors, optical sensors such as fluorescence and surface plasmon resonance, and electrochemical types for the diagnosis of HER-2 and the effectiveness of some drugs against that. Attention to developing some types of biosensor devices such as colorimetric biosensors for HER-2 detection can be an important point in future studies.

Expression and Content of Protein LC3B in Gastric Cancer Tissue, Relationship with Expression of mTOR, AMPK in Gastric Cancer Tissue and HER2 and PD-L1 Status of the Tumor

Analysis of HER2 status of the tumor and expression of mTOR, AMPK showed a decrease in mTOR mRNA level in HER2+ tumors in comparison with HER- status. The appearance of PD-L1+ transformed cells in the tumor was associated with increased expression of the LC3B gene and elevated content of the corresponding protein measured after treatment.