HER2 Gene Research Articles

Role of Harmaline in Inhibiting c-Myc, Altering Molecular Typing, and Promoting Apoptosis in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) lacks effective targeted, endocrine therapeutic agents and the development of novel agents is costly and time-consuming. The objective of this study was to identify pharmaceuticals and natural products utilized in clinical practice that have the potential to inhibit the expression of Cellular-myelocytomatosis oncogene (c-Myc), based on a review of the current literature. The aim was to assess the effect of the specified drugs on c-Myc expression in TNBC cells, determine the most potent inhibitor, and evaluate its impact on TNBC cell proliferation, invasive migration, and apoptosis, as well as the expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2) at both the gene and protein levels. Explore its potential for treatment or adjuvant therapy for triple-negative breast cancer. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to quantify gene and protein expression levels. Flow cytometry was employed to measure cell proliferation and apoptosis, while the Transwell assay was utilized to assess cell invasion and migration. Harmaline emerged as the strongest inhibitor, significantly decreasing the expression of c-Myc at both the gene and protein levels in TNBC cells. It also inhibited cell proliferation, invasion, and migration while promoting apoptosis in TNBC cells. Additionally, there was a varying increase in the expression of ER and PR genes and proteins. While the expression of the HER-2 gene was elevated, there was no significant change in HER-2 protein levels. Notably, the expression of the phosphorylated HER-2 protein increased. Harmaline was found to promote apoptosis and inhibit cell proliferation, invasion, and migration in TNBC cells by targeting the inhibition of c-Myc. It also induced the re-expression of the ER, PR, and HER-2 genes, as well as the ER and PR proteins.

HER-2 expression is correlated with multimodal imaging features in breast cancer: a pilot study

Objective A pilot study to evaluate the correlation between multimodal imaging features and the expression of the human epidermal growth factor receptor type 2 (HER-2) in breast cancer to provide a basis for clinical treatment and prognosis evaluation. Methods We included a total of 62 patients with breast cancer admitted to the Affiliated Hospital of Hebei University between 2018 and 2022. All of them underwent the relevant investigations, including ultrasound, mammography, and enhanced magnetic resonance imaging (MRI), in the hospital within one month before surgery or biopsy. HER-2 expression level was divided into negative and positive by immunohistochemistry(IHC). Using SPSS 24.0 statistical software to analyze the differences in imaging features between the HER-2 positive and the HER-2 negative groups. Results There was a statistically significant difference between the HER-2 positive and the HER-2 negative groups (p = 0.005) in the hyperechoic halo sign around the lesion detected by ultrasonography as well as in the apparent diffusion coefficient (ADC) on MRI (p = 0.047). The sensitivity and specificity of the hyperechoic halo sign in predicting HER-2 positivity was 48.3% and 84.8% respectively, and the area under the curve (AUC) for the ADC value to predict HER-2 expression was 0.533. When b was equal to 800 and the ADC value (cutoff value) was 0.000888 mm2/s, the sensitivity and specificity were 65.5% and 51.5%, respectively. Conclusion A combination of multimodal imaging features and HER-2 gene expression can provide more valuable information for clinical diagnosis and therapeutic schedule in breast cancer.

Survival outcomes for HER2-low breast cancer: Danish national data.

We investigated the prognosis of breast cancer (BC) with low expression of human epidermal growth factor receptor 2 (HER2), as previous studies have found varying impacts on survival of HER2-low BC compared with HER2 0 BC (HER2 IHC score of 0). HER2-low is defined as a score of 1+ or 2+ in an immunohistochemical (IHC) assay without HER2 gene amplification. Patients with HER2 0 or HER2-low BC from the national Danish Breast Cancer Group database were examined by multivariable survival analysis in a retrospective noninterventional investigation. Patients were grouped as either HER2 0 or HER2-low. The primary endpoint was time to recurrence (TR), and the secondary endpoints were overall survival (OS) and distant recurrence-free interval (DRFI). 41,610 patients were included (12,981 with HER2 0 BC and 28,629 with HER2-low BC). HER2-low BC was associated with a lower risk of recurrence (hazard ratio [HR]: 0.92, p = 0.03). Regarding secondary endpoints, HER2-low disease was linked to improved overall OS (HR: 0.94, p = 0.02). No statistically significant effect of HER2-low was found for DRFI, along with no differential effect of HER2-low according to estrogen receptor (ER) status. HER2-low BC was found to show an improved HR for OS and DRFI compared with HER2 0 BC; however, further studies are need to establish whether it represents a separate biological entity.

Differentiating HER2-low and HER2-zero tumors with 21-gene multigene assay in 2,295 HR + HER2- breast cancer: a retrospective analysis

BackgroundHER2-positivity is an essential marker for therapeutic decisions, while HER2 expression is heterogenous. In recent years, there has been increasing recognition of a subgroup of breast cancer patients who have low levels of HER2 expression, also known as HER2-low because trastuzumab deruxtecan offers clinical benefit for patients with HER2-low metastatic breast cancer. Despite the growing interest in HER2-low breast cancer, there is limited research on how multigene assays can help differentiate between HER2-low and HER2-negative breast cancer. Among HR + HER2- breast cancer, we compared genomic characteristics between HER2-low and HER2-zero using the 21-gene assay.MethodsA retrospective review of clinical records was performed in 2,295 patients who underwent Oncotype DX® test in two hospitals between 2013 and 2020. Patients were classified into two groups as the HER2-zero and HER2-low based on HER2 immunohistochemistry. In cases with HER2 2+, no amplification of HER2 gene was confirmed by silver in situ hybridization. High genomic risk was defined as cases with 21-gene recurrence score (RS) > 25. Multivariable binary logistic-regression analysis was performed.ResultsOf these, 944 (41.1%) patients were assigned to the HER2-zero group, while 1351 (58.9%) patients were assigned to the HER2-low group. The average Recurrence Score (RS) was found to be 17.802 in the HER2-zero breast cancer group and 18.503 in the HER2-low group, respectively (p-value < 0.005). When comparing the proportion of high RS between the two groups, the HER2-zero group had a high RS rate of 12.4% (117 out of 944), while the HER2-low group had a high RS rate of 17.0% (230 out of 1351) (p = 0.002). The HER2 score identified by qRT-PCR was 8.912 in the HER2-zero group and 9.337 in the HER2-low group (p < 0.005). In multivariable analysis, HER2-low status was found to be an independent factor for high RS, with an odds ratio of 1.517 (1.172–1.964), independent of ER, PR, and Ki67. Within the subgroup of patients with invasive ductal carcinoma, the high RS rates were 19% in the HER2-low group and 14% in the HER2-zero group. However, when considering all patients, there were no significant differences observed in recurrence-free survival and overall survival between the HER2-low and HER2-zero groups.ConclusionWithin HR + HER2- breast cancer, HER2-low tumors are associated with high RS, especially for histologically invasive ductal carcinoma. A prognostic influence of HER2-low expression among HR + HER2- breast cancer remains as an area that requires further study.

Prospective Validation of a One-Step RT-qPCR-based Test for Quantifying HER2 Gene Expression in Breast Cancer.

To Validate a one-step RT-qPCR as a reliable diagnostic tool in HER-2 positive breast cancer. Further, establishing this tool as a standard procedure to quantify HER-2 expression in Breast cancer patient. Here we report a prospective validation study that shows the concordance of one-step RT-qPCR in assessing the HER2 levels in formalin-fixed paraffin-embedded (FFPE) tissue samples with the current paradigm of diagnosis such as Immunohistochemistry (IHC) and Fluorescence-in-situ Hybridization (FISH). We collected 275 FFPE samples from the Department of Pathology, Ibn Rochd University Hospital Center. IHC was carried out in all the samples and those with a score of 2+ were also analyzed using FISH. We extracted mRNA from FFPE samples and performed RT-qPCR, and the results were compared with those obtained using IHC/FISH. HER2 mRNA levels were quantified and normalized using the reference genes RPL30 and RPL37, based on our earlier reports. HER2 cut-off value was fixed at 11.954 corresponding to the combination of the best sensitivity and specificity (93.4% and 100%) respectively, and with positive predictive values PPV that reached 100% and a negative predictive value NPV that reached 89.4%. The results showed 100% concordance with FISH. The Kappa coefficient was 0.863 which indicated concordance with IHC. The area under the curve (AUC) which is an important parameter that determines the diagnostic accuracy of the test was calculated as AUC=0.955. The results were comparable to some of the recent studies published in a similar direction. Our study shows that one-step RT-qPCR-based quantitation is an accurate and reproducible test to record HER2 gene expression for a better treatment orientation focusing on maximal therapeutic and survival outcome.

Computational approach for counting of SISH amplification signals for HER2 status assessment.

The human epidermal growth factor receptor 2 (HER2) gene is a critical biomarker for determining amplification status and targeting clinical therapies in breast cancer treatment. This study introduces a computer-aided method that automatically measures and scores HER2 gene status from invasive tissue regions of breast cancer using whole slide images (WSI) through silver in situ hybridization (SISH) staining. Image processing and deep learning techniques are employed to isolate untruncated and non-overlapping single nuclei from cancer regions. The Stardist deep learning model is fine-tuned on our HER2-SISH data to identify nuclei regions, followed by post-processing based on identified HER2 and CEP17 signals. Conventional thresholding techniques are used to segment HER2 and CEP17 signals. HER2 amplification status is determined by calculating the HER2-to-CEP17 signal ratio, in accordance with ASCO/CAP 2018 standards. The proposed method significantly reduces the effort and time required for quantification. Experimental results demonstrate a 0.91% correlation coefficient between pathologists manual enumeration and the proposed automatic SISH quantification approach. A one-sided paired t-test confirmed that the differences between the outcomes of the proposed method and the reference standard are statistically insignificant, with p-values exceeding 0.05. This study illustrates how deep learning can effectively automate HER2 status determination, demonstrating improvements over current manual methods and offering a robust, reproducible alternative for clinical practice.

The Prospective role of lapatinib as an adjuvant therapy in prevalent cancers: Insights from in silico analysis targeting EGFR and HER2

IntroductionVarious pieces of evidence suggest an elevation in the levels of EGFR and HER2 in different cancers leading to the proliferation, invasion, and metastasis of cancer cells. In this study, we conducted a comprehensive investigation into the expression alterations of these two receptors in various cancers using in silico data. In addition, we investigated the therapeutic potential of lapatinib as an inhibitor of these receptors in various cancer types. MethodsRNAseq data for prevalent cancers were downloaded from The Cancer Genome Atlas (TCGA). After initial preprocessing, expression changes of HER2, EGFR, and candidate genes—identified based on their association with EGFR and HER2 signaling pathways—were examined. Human protein atlas data were utilized to assess the protein expression of HER2 and EGFR. GSE129254 was employed to identify molecular pathways and candidate genes associated with lapatinib. The protein-protein interaction network was used to identify lapatinib-influenced hub genes. Clinical data for common cancers were used to investigate the correlation between the expression of candidate genes and patients' mortality rates by Cox regression test. ResultsThe findings clearly indicated a significant increase in the expression levels of HER2 and EGFR in cancers such as kidney, lung, breast, bladder, pancreas, head and neck, stomach, and endometrial, both at the mRNA and protein levels (p-value <0.01). Additionally, more than 30 % of samples in some cancers showed a twofold increase in HER2 or EGFR expression. The analysis of GSE129254 data revealed that lapatinib reduces the expression of numerous genes associated with cell proliferation. METTL1, LYAR, LTV1, CCND1, NOP2, and DDX21 were identified as hub genes related to the effect of lapatinib. Our results demonstrated that many hub genes exhibited elevated expression in candidate cancers, and the upregulation of some of them was correlated with poor prognosis. ConclusionOur results indicate an upregulation in the expression levels of HER2 and EGFR in certain common cancers, suggesting that lapatinib, in addition to breast cancer, could be considered for the treatment of these cancers. Furthermore, we demonstrated that some genes with increased expression in prevalent cancers and associated with poor prognosis have the potential to be modulated by lapatinib.

Molecular investigation of Her2 gene in Breast Cancer Women In Babylon City

Background: The most prevalent illness in women is breast cancer, “Human epidermal growth factor receptor 2 (HER2)” plays a significant role in the carcinogenesis of breast cancer. (HER2)” overexpression can arise from several causes and is frequently observed in 20–30% of instances of breast cancer. Aim of the study: The current study was aimed to investigate the correlation between the existence of HER2 gene expression in the peripheral blood samples with breast cancer females by using the primers of HER2 gene and PCR technique. Materials and Methods: In this study, seventy two (72) peripheral Blood samples were taken from the breast cancer ladies from Marjan Hospital's at Oncology Center in Babylon city's who had previously received a confirmatory diagnosis of breast cancer with ten (10) blood samples from clinically healthy women as a control group during the period from June 2022 to January 2023, DNA samples were isolated from the collected blood samples by DNA Extraction kit (FavorPrepTM Blood/Cultured Cells Genomic DNA Extraction Mini Kit), then, conventional PCR technique was performed with specific oligo primers to amplify the Her2 gene's target sequence in those DNA samples, then, agarose gel electrophoresis was applied for detecting the target sequence in the DNA products with the band size 150bp. Results: 58 / 72(80.5 %) of the DNA samples were positive and 14/ 72 (19. 5%) were negative for Her2 gene in the peripheral blood samples of the breast cancer women. Conclusions: in conclusion the current study's results demonstrated that 58/ 72 (80.5%) of the peripheral blood samples from breast cancer women were positive and the remaining 14/ 72(19.5%) of the peripheral blood samples were negative for Her-2 gene, “HER2 gene” can be considered as a useful biomarker and an obvious indicator for breast cancer which could be employed for early and confirmatory diagnosis of breast cancer in women.

Review of In Situ Hybridization (ISH) Stain Images Using Computational Techniques.

Recent advancements in medical imaging have greatly enhanced the application of computational techniques in digital pathology, particularly for the classification of breast cancer using in situ hybridization (ISH) imaging. HER2 amplification, a key prognostic marker in 20-25% of breast cancers, can be assessed through alterations in gene copy number or protein expression. However, challenges persist due to the heterogeneity of nuclear regions and complexities in cancer biomarker detection. This review examines semi-automated and fully automated computational methods for analyzing ISH images with a focus on HER2 gene amplification. Literature from 1997 to 2023 is analyzed, emphasizing silver-enhanced in situ hybridization (SISH) and its integration with image processing and machine learning techniques. Both conventional machine learning approaches and recent advances in deep learning are compared. The review reveals that automated ISH analysis in combination with bright-field microscopy provides a cost-effective and scalable solution for routine pathology. The integration of deep learning techniques shows promise in improving accuracy over conventional methods, although there are limitations related to data variability and computational demands. Automated ISH analysis can reduce manual labor and increase diagnostic accuracy. Future research should focus on refining these computational methods, particularly in handling the complex nature of HER2 status evaluation, and integrate best practices to further enhance clinical adoption of these techniques.

Evaluation of HER2 immunohistochemistry-positive and immunohistochemistry-negative FISH amplification breast cancers using next-generation sequencing

Abstract Objectives In this study, we aimed to assess the concordance between HER2 positivity, defined as scores of 2+ or 3+ by immunohistochemistry (IHC), and HER2 gene amplification results obtained by fluorescence in situ hybridization (FISH) and gene panel testing (GPT). Methods A total of 45 breast cancer patients with sufficient biopsy, breast-conserving surgery, or mastectomy specimens collected between 2018 and 2024 at Hokuto Hospital were included in the study. HER2 status was defined as HER2+ in cases with scores of 3+ on IHC staining, HER2-FISHamp in cases with scores of 2+ on IHC staining plus FISH amplification. FISH amplification was defined as a ratio of HER2 to the amplification of the chromosome 17 centromere ≥2.0. Next-generation sequencing (NGS) for these genes was conducted using MiSeq. The criterion for ERBB2 amplification requires gene amplification of more than 2 standard deviations (SD) above the average of the panel genes and CN ≥4. Results HER2+ correlated with the presence of NGS amplification of ERBB2 (p&lt;0.001). NGS amplification was significantly more detectable in HER2+ than in HER2-FISHamp. HER2-FISHamp correlated with larger tumor size (p=0.009) and the presence of lymph node metastases (p&lt;0.001). No correlations were observed between the HER2 status and other parameters such as age, histological grade, stage histological type, recurrence, treatment response evaluation, and breast cancer mortality. Conclusions To achieve a comprehensive diagnosis, it is crucial to integrate GPT findings with other diagnostic approaches and to have a though understanding of the characteristics and limitations of each method.

Protein Expression, Amplification, and Mutation of HER2 Gene in Canine Primary Pulmonary Adenocarcinomas: Preliminary Results.

Recently, human epidermal growth factor receptor 2 (HER2) has emerged as a therapeutic target of interest for non-small-cell lung cancer in humans. The role of HER2 in canine pulmonary adenocarcinomas is poorly documented. To address this gap, this study employed three methodologies: immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and next-generation sequencing (NGS) to investigate the protein expression, gene amplification, and mutation of HER2 in 19 canine primary pulmonary adenocarcinomas. By IHC, 3 out of 19 cases were overexpressed 3+, 6 were 2+, and 10 were negative. With FISH, 2 cases were amplified (12.5%), 3 were inadequate for the analyses, and the others were non-amplified. With NGS, seven cases were inadequate. All other cases were wild-type, except for one IHC 3+ case, which was amplified with FISH and with a specific mutation already described in human pulmonary adenocarcinoma, V659E. This mutation is probably sensitive to tyrosine kinase inhibitory drugs. These results are similar to those in human medicine and to the few data in the literature on canine lung carcinomas; the presence of 12.5% of amplified cases in dogs lays the foundation for future targeted drugs against HER2 alterations.

Epithelial-Mesenchymal Transition Indexes in Triple-Negative Breast Cancer Progression and Metastases.

Background Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer characterized by the lack of expression of estrogen and progesterone receptors and the absence of HER2 protein overexpression or gene amplification. How TNBC becomes so aggressive at the molecular level is not yet fully understood. The epithelial-mesenchymal transition (EMT) has been increasingly recognized as playing a pivotal role in cancer progression and metastasis. This study aimed to elucidate the connection between TNBC progression with EMT-related markers, including vimentin, beta-catenin, and E-cadherin. Methodology Rigorous immunohistochemical analysis was employed to assess the expression of vimentin, beta-catenin, and E-cadherin in primary tumors, tumor buds, and lymph node metastases (LNMs) from 137 cases with an invasive ductal carcinoma triple-negative phenotype diagnosed between 2018 and 2024. The EMT index, which was especially important in our work, is the sum of vimentin and beta-catenin expression divided by that of E-cadherin. Estimated Pearson correlation, multiple linear regression, and Kruskal-Wallis tests were used to determine the relationships of the EMT index with tumor buds and tumor-infiltrating lymphocytes (TILs). Results Vimentin highly correlated within separate regions of interest with Pearson correlation ranging from 0.90 to 0.92 (p < 0.001). Strong negative correlations between E-cadherin and vimentin (r = -0.81 to - 0.89, p < 0.001) showed its role in preserving the epithelial phenotype. The presence of tumor buds, aggregates, or clusters of cancer cells shed from the primary tumor mass invading the connective tissue showed very strong associations with the EMT index (r = 0.91, p < 0.001). Its presence is suggestive of aggressive disease and may identify a high-risk subpopulation that may benefit from more active surveillance or adjuvant treatment. Similarly, TILs correlated inversely with the EMT index (r = -0.90, p < 0.001). The most significant predictor of the EMT index, i.e., vimentin, had a model R-squared value of 1.000 in the regression analysis. Conclusions This study brings to light the importance of EMT-related markers in TNBC progression, with special emphasis on tumor buds as possible prognostic indicators for aggressive disease. The negative correlation of TILs with the EMT index indicates that an effective immune response could antagonize EMT-mediated tumor progression. These results suggest that EMT-based treatments in TNBC should be designed from a multimarker perspective by including interactions among several markers to optimize predictions and therapeutics. The results hold the potential to set future research directions and actionable outcomes that could influence clinical utility in the battle against TNBC.

HER2 amplification subtype intrahepatic cholangiocarcinoma exhibits high mutation burden and T cell exhaustion microenvironment

ObjectiveThis study aimed to establish a uniform standard for the interpretation of HER2 gene and protein statuses in intrahepatic cholangiocarcinoma (ICC). We also intended to explore the clinical pathological characteristics, molecular features, RNA expression and immune microenvironment of HER2-positive ICC.MethodsWe analyzed a cohort of 304 ICCs using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) to identify HER2 status. Comprehensive analyses of the clinicopathological, molecular genetic, and RNA expression characterizations of ICCs with varying HER2 statuses were performed using next-generation sequencing. We further investigated the tumor microenvironment of ICCs with different HER2 statuses using IHC and multiplex immunofluorescence staining.ResultsHER2/CEP17 ratio of ≥ 2.0 and HER2 copy number ≥ 4.0; or HER2 copy number ≥ 6.0 were setup as FISH positive criteria. Based on this criterion, 13 (4.27%, 13/304) samples were classified as having HER2 amplification. The agreement between FISH and IHC results in ICC was poor. HER2-amplified cases demonstrated a higher tumor mutational burden compared to non-amplified cases. No significant differences were observed in immune markers between the two groups. However, an increased density of CD8 + CTLA4 + and CD8 + FOXP3 + cells was identified in HER2 gene-amplified cases.ConclusionFISH proves to be more appropriate as the gold standard for HER2 evaluation in ICC. HER2 gene-amplified ICCs exhibit poorer prognosis, higher mutational burden, and T cell exhaustion and immune suppressed microenvironment.

Systematic assessment of HER2 status in ductal carcinoma in situ of the breast: a perspective on the potential clinical relevance

In many countries, hormone receptor status assessment of ductal carcinoma in situ (DCIS) is routinely performed, as hormone receptor-positive DCIS patients are eligible for adjuvant anti-hormonal treatment, aiming to reduce the ipsilateral and contralateral breast cancer risk. Although HER2 gene amplification and its associated HER2 protein overexpression constitute a major prognostic and predictive marker in invasive breast carcinoma, its use in the diagnosis and treatment of DCIS is less straightforward. HER2 immunohistochemistry is not routinely performed yet, as the role of HER2-positivity in DCIS biology is unclear. Nonetheless, recent data challenge this practice. Here, we discuss the value of routine HER2 assessment for DCIS. HER2-positivity correlates strongly with DCIS grade: around four in five HER2-positive DCIS show high grade atypia. As morphological DCIS grading is prone to interobserver variability, HER2 immunohistochemistry could render grading more robust. Several studies showed an association between HER2-positive DCIS and ipsilateral recurrence risk, albeit currently unclear whether this is for overall, in situ or invasive recurrence. HER2-positive DCIS tends to be larger, with a higher risk of involved surgical margins. HER2-positive DCIS patients benefit more from adjuvant radiotherapy: it substantially decreases the local recurrence risk after lumpectomy, without impact on overall survival. HER2-positivity in pure biopsy-diagnosed DCIS is associated with increased upstaging to invasive carcinoma after surgery. HER2 immunohistochemistry on preoperative biopsies might therefore provide useful information to surgeons, favoring wider excisions. The time seems right to consider DCIS subtype-dependent treatment, comprising appropriate local treatment for HER2-positive DCIS patients and de-escalation for hormone receptor-positive, HER2-negative DCIS patients.

A plain language summary of the results from the phase 2b HERIZON-BTC-01 study of zanidatamab in participants with HER2-amplified biliary tract cancer.

Researchers wanted to study whether the research drug zanidatamab could help people with a type of cancer called biliary tract cancer. In some people, biliary tract cancer cells make extra copies of a gene called HER2 (also called ERBB2). This is known as being HER2-amplified. Zanidatamab is an antibody designed to destroy cancer cells that have higher-than-normal HER2 protein or gene levels. Zanidatamab is currently under research and is not yet approved for any diseases. Participants in this phase 2b clinical study had tumors that were HER2-amplified and at the advanced or metastatic stage. Participants also had cancer which had become worse after previous chemotherapy or had side effects that were too bad to continue chemotherapy. They also had to meet other requirements to be enrolled. Researchers measured the amount of HER2 protein in the tumor samples of the participants who were enrolled. There were 80 participants with tumors that were both HER2 amplified and had higher-than-normal HER2 protein amounts (considered to be 'HER2-positive'). There were 7 participants with tumors that were HER2-amplified, but had little-to-no levels of the HER2 protein (considered to be 'HER2-low'). All participants in the study were treated with zanidatamab and no other cancer treatments once every 2weeks. In the HER2-positive group, 33 of 80 (41%) participants had their tumors shrink by 30% or more of their original size. In half of these participants, their tumors did not grow for 13months or longer. No participant in the HER2-low group had their tumors shrink by 30% or more. In total, 63 of 87 participants (72%) had at least one side effect believed to be related to zanidatamab treatment. Most side effects were mild or moderate in severity. No participant died from complications related to zanidatamab. Diarrhea was one of the more common side effects and was experienced by 32 of 87 participants (37%). Side effects related to receiving zanidatamab through the vein, such as chills, fever, or high blood pressure, were experienced by 29 of 87 participants (33%). The results of this study support the potential for zanidatamab as a new therapy for people with HER2-positive biliary tract cancer after they had already received chemotherapy. More research is occurring to support these results.Clinical Trial Registration: NCT04466891 (HERIZON-BTC-01 study).

Image analysis for bright-field HER2 in situ hybridization: validation for clinical use.

The aim of the present study was to develop and validate a quantitative image analysis (IA) algorithm to aid pathologists in assessing bright-field HER2 in situ hybridization (ISH) tests in solid cancers. A cohort of 80 sequential cases (40 HER2-negative and 40 HER2-positive) were evaluated for HER2 gene amplification with bright-field ISH. We developed an IA algorithm using the ISH Module from HALO software to automatically quantify HER2 and CEP17 copy numbers per cell as well as the HER2/CEP17 ratio. We observed a high correlation of HER2/CEP17 ratio, an average of HER2 and CEP17 copy number per cell between visual and IA quantification (Pearson's correlation coefficient of 0.842, 0.916, and 0.765, respectively). IA was able to count from 124 cells to 47,044 cells (median of 5565 cells). The margin of error for the visual quantification of the HER2/CEP17 ratio and of the average of HER2 copy number per cell decreased from a median of 0.23 to 0.02 and from a median of 0.49 to 0.04, respectively, in IA. Curve estimation regression models showed that a minimum of 469 or 953 invasive cancer cells per case is needed to reach an average margin of error below 0.1 for the HER2/CEP17 ratio or for the average of HER2 copy number per cell, respectively. Lastly, on average, a case took 212.1s to execute the IA, which means that it evaluates about 130 cells/s and requires 6.7s/mm2. The concordance of the IA software with the visual scoring was 95%, with a sensitivity of 90% and a specificity of 100%. All four discordant cases were able to achieve concordant results after the region of interest adjustment. In conclusion, this validation study underscores the usefulness of IA in HER2 ISH testing, displaying excellent concordance with visual scoring and significantly reducing margins of error.

Overcoming retinoic acid resistance in HER2-enriched breast cancers: role of MYC.

HER2-enriched (HER2+) breast cancers express high levels of the growth-promoting HER2 protein. Although these cancers are treated with the HER2-targeted drug, trastuzumab, resistance to treatment is common. Retinoic acid (RA) is an anti-cancer agent that has been successfully used for the treatment of leukemia and holds promise for the treatment of solid cancers, including breast cancer. The HER2 gene is frequently co-amplified with RARA, a key determinant of RA sensitivity in breast cancers. It seems surprising, therefore, that HER2+ breast cancers are refractory to RA treatment. Here, we show that MYC mediates RA resistance by suppressing the expression of cellular retinoic acid binding protein 2 (CRABP2), resulting in RARα inactivation. CRABP2 is an intracellular RA transporter that delivers RA to the nuclear receptor RARα for its activation. Our results indicate that response to RA is enhanced by MYC depletion in HER2+ breast cancer cells and that RA treatment enhances trastuzumab responsiveness. Our findings support the use of RA and trastuzumab for the treatment of subsets of patients with breast cancers that are HER2-RARα co-amplified and have low levels of MYC.

HER2 status results in an unstable switch from primary to recurrent breast cancer.

Accurately distinguishing HER2-2+ tumors from HER2-0/1+ tumors via immunohistochemistry (IHC) is still very challenging. HER2 IHC 2+ is considered to indicate moderate expression and is easier to distinguish, with more reliable results in previous and current clinical practice. We focused on HER2-2+ patients and evaluated the switch in HER2 status between primary and paired recurrent disease patients to evaluate the discordance of HER2-2+ expression. We included patients who were HER2-2+ of primary or rebiopsy tumor samples, to evaluate the evolution of HER2-2+ expression. In the cohort with a total of 159 patients with HER2-2+ expression in either primary tumor or locoregional/distant metastasis samples, 44.0% had HER2-2+ in primary tumor and 88.8% in recurrent disease. Among patients with primary and recurrent HER2-2+ breast cancers, 18.5% and 15.2% of the patients, respectively, had HER2 gene amplification via ISH. The overall rate of discordance in HER2 IHC results was 67.1%. Among primary HER2-2+ patients, 74.6% were maintained in the HER2-2+ cohort at the recurrence. The discordance was mostly driven by patients switching from HER2-2+ to HER2-1+ (64.7%). Among HER2-2+ recurrent patients, discordance in the IHC results was mostly driven by switching from HER2-0 to HER2-2+ (47.1%). When HER2-low was added to the analysis, the overall rate of HER2 discordance was 40.4%. The proportion of patients with discordant HER2 expression was significantly greater among HR-positive patients than negative patients (44.1% vs. 21.7%, p=0.062). HER2 expression in primary and recurrent breast cancer samples was highly unstable. Discordance was more frequently observed in the HR-positive population.

A platform to deliver single and bi-specific Cas9/guide RNA to perturb genes in vitro and in vivo

Although CRISPR/Cas9 technology is poised to revolutionize the treatment of diseases with underlying genetic mutations, it faces some significant issues limiting clinical entry. They include low-efficiency in vivo systemic delivery and undesired off-target effects. Here, we demonstrate, by modifying Cas9 with phosphorothioate DNA oligos (PS), one can efficiently deliver single and bi-specific CRISPR/Cas9/guide RNA (gRNA) dimers in vitro and in vivo with reduced off-target effects. We show that PS-Cas9/gRNA-mediated gene knockout preserves chimeric antigen receptor T cell viability and expansion in vitro and in vivo. PS-Cas9/gRNA mediates gene perturbation in patient-derived tumor organoids and mouse xenograft tumors, leading to potent tumor antitumor effects. Further, HER2 antibody-PS-Cas9/gRNA conjugate selectively perturbs targeted genes in HER2+ ovarian cancer xenografts in vivo. Moreover, we created bi-specific PS-Cas9 with two gRNAs to target two adjacent sequences of the same gene, leading to efficient targeted gene disruption ex vivo and in vivo with markedly reduced unintended gene perturbation. Thus, the cell-penetrating PS-Cas9/gRNA can achieve efficient systemic delivery and precision in gene disruption.

Histogenetic insights and genetic landscape of fibromatosis-like undifferentiated gastric carcinoma: a focused study

BackgroundThe aim of this study was to elucidate the histogenesis and genetic underpinnings of fibromatosis-like undifferentiated gastric carcinoma (FLUGC), a rare pathological entity.MethodThrough a detailed analysis of seven cases, including histopathological evaluation, CTNNB1 gene mutation screening, human epidermal growth factor receptor 2 (HER2) protein level quantification, and HER2 gene amplification assessment to identify the pathological and molecular characteristics of FLUGC.ResultsOf the seven patients in this study, five were male and two were female (age: 39–73 years). Four patients presented with lesions in the gastric antrum and three had lesions in the lateral curvature of the stomach. Histopathologically, over 90% of the tumor consisted of aggressive fibromatosis-like tissue, including proliferating spindle fibroblasts and myofibroblasts and varying amounts of collagenous fibrous tissues. Undifferentiated cancer cells, accounting for less than 10%, were dispersed among the aggressive fibromatosis-like tissues. These cells were characterized by their small size and were relatively sparse without glandular ducts or nested mass-like structures. Immunophenotyping results showed positive expression of CKpan, CDX2, villin, and p53 in undifferentiated cancer cells; positive expression of vimentin in aggressive fibromatosis-like tissue; positive cytoplasmic expression of β-catenin; and focal cytoplasmic positive expression of smooth muscle actin (SMA). Genetic analysis did not reveal any mutations in the CTNNB1 gene test, nor was there amplification in the HER2 gene fluorescence in situ hybridization (FISH) test. Additionally, the Epstein-Barr encoding region (EBER) of in situ hybridization was negative; and the mismatch repair (MMR) protein was positive. Programmed cell death-1 (PD-1) was < 1–5%; programmed cell death ligand 1 (PD-L1): TPS = 1–4%, CPS = 3–8.ConclusionThe study highlights the significance of CTNNB1, HER2, EBER, and MMR as pivotal genetic markers in FLUGC, underscoring their relevance for diagnosis and clinical management. The rarity and distinct pathological features of FLUGC emphasize the importance of accurate diagnosis to prevent underdiagnosis or misdiagnosis and to raise awareness within the medical community.