HER2 aberrations in cancer: implications for therapy

Disrupting EGFR-HER2 Transactivation by Pertuzumab in HER2-Positive Cancer: Quantitative Analysis Reveals EGFR Signal Input as Potential Predictor of Therapeutic Outcome

Pertuzumab (Perjeta®), a humanized antibody binding to the dimerization arm of HER2 (Human epidermal growth factor receptor-2), has failed as a monotherapy agent in HER2 overexpressing malignancies. Since the molecular interaction of HER2 with ligand-bound EGFR (epidermal growth factor receptor) has been implied in mitogenic signaling and malignant proliferation, we hypothesized that this interaction, rather than HER2 expression and oligomerization alone, could be a potential molecular target and predictor of the efficacy of pertuzumab treatment. Therefore, we investigated static and dynamic interactions between HER2 and EGFR molecules upon EGF stimulus in the presence and absence of pertuzumab in HER2+ EGFR+ SK-BR-3 breast tumor cells using Förster resonance energy transfer (FRET) microscopy and fluorescence correlation and cross-correlation spectroscopy (FCS/FCCS). The consequential activation of signaling and changes in cell proliferation were measured by Western blotting and MTT assay. The autocorrelation functions of HER2 diffusion were best fitted by a three-component model corrected for triplet formation, and among these components the slowly diffusing membrane component revealed aggregation induced by EGFR ligand binding, as evidenced by photon-counting histograms and co-diffusing fractions. This aggregation has efficiently been prevented by pertuzumab treatment, which also inhibited the post-stimulus interaction of EGFR and HER2, as monitored by changes in FRET efficiency. Overall, the data demonstrated that pertuzumab, by hindering post-stimulus interaction between EGFR and HER2, inhibits EGFR-evoked HER2 aggregation and phosphorylation and leads to a dose-dependent decrease in cell proliferation, particularly when higher amounts of EGF are present. Consequently, we propose that EGFR expression on HER2-positive tumors could be taken into consideration as a potential biomarker when predicting the outcome of pertuzumab treatment.

Preclinical Evaluation of HER2-Targeting DARPin G3: Impact of Albumin-Binding Domain (ABD) Fusion

Designed ankyrin repeat protein (DARPin) G3 is an engineered scaffold protein. This small (14.5 kDa) targeting protein binds with high affinity to human epidermal growth factor receptor 2 (HER2). HER2 is overexpressed in several cancers. The use of the DARPin G3 for radionuclide therapy is complicated by its high renal reabsorption after clearance via the glomeruli. We tested the hypothesis that a fusion of the DARPin G3 with an albumin-binding domain (ABD) would prevent rapid renal excretion and high renal reabsorption resulting in better tumour targeting. Two fusion proteins were produced, one with the ABD at the C-terminus (G3-ABD) and another at the N-terminus (ABD-G3). Both variants were labelled with 177Lu. The binding properties of the novel constructs were evaluated in vitro and their biodistribution was compared in mice with implanted human HER2-expressing tumours. Fusion with the ABD increased the retention time of both constructs in blood compared with the non-ABD-fused control. The effect of fusion with the ABD depended strongly on the order of the domains in the constructs, resulting in appreciably better targeting properties of [177Lu]Lu-G3-ABD. Our data suggest that the order of domains is critical for the design of targeting constructs based on scaffold proteins.

If it's a target, it's a pan-cancer target: Tissue is not the issue

Cancer is traditionally diagnosed and treated on the basis of its organ of origin (e.g., lung or colon cancer). However, organ-of-origin diagnostics does not reveal the underlying oncogenic drivers. Fortunately, molecular diagnostics have advanced at a breathtaking pace, and it is increasingly apparent that cancer is a disease of the genome. Hence, we now have multiple genomic biomarker-based, tissue-agnostic Food and Drug Administration approvals for both gene- and immune-targeted therapies (larotrectinib/entrectinib, for NTRK fusions; selpercatinib, RET fusions; dabrafenib plus trametinib, BRAFV600E mutations; pembrolizumab/dostarlimab, microsatellite instability; and pembrolizumab for high tumor mutational burden; pemigatinib is also approved for FGFR1-rearranged myeloid/lymphoid neoplasms). There are emerging targets as well, including but not limited to ALK, BRCA and/or homologous repair deficiency, ERBB2 (HER2), IDH1/2, KIT, KRASG12C, NRG1, and VHL. Many tissue-agnostic approvals center on rare/ultra-rare biomarkers (often < 1 % of cancers), necessitating screening hundreds of tumors to find a single one harboring the cognate molecular alteration. Approval has generally been based on small single-arm studies (<30-100 patients) with high response rates (>30 % to > 75 %) of remarkable durability. Because of biomarker rarity, single-gene testing is not practical; next generation sequencing of hundreds of genes must be performed to obtain timely answers. Resistance to biomarker-driven therapeutics is often due to secondary mutations or co-driver gene defects; studies are now addressing the need for customized drug combinations matched to the complex molecular alteration portfolio in each tumor. Future investigation should expand tissue-agnostic therapeutics to encompass both hematologic and solid malignancies and include biomarkers beyond those that are DNA-based.

Trastuzumab deruxtecan in patients with locally advanced or metastatic HER2-positive gastric cancer: a multicenter, open-label, expanded-access study

BACKGROUND

Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate that consists of an anti-human epidermal growth factor receptor 2 (HER2) antibody bound by a cleavable tetrapeptide-based linker to a cytotoxic topoisomerase I inhibitor. Prior to marketing approval in Japan in September 2020, this expanded-access study was conducted to provide T-DXd to previously treated patients with locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinomas.

METHODS

This multicenter, open-label, expanded-access study was conducted between March 25 and September 25, 2020 at 17 Japanese sites. Previously treated patients with locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinomas received T-DXd 6.4 mg/kg via intravenous infusions at 3-week intervals. Serious adverse events (SAEs), all potential cases of interstitial lung disease (ILD)/pneumonitis, all liver-related events potentially meeting Hy's Law criteria, and all cases of overdose were reported on the case report forms.

RESULTS

A total of 64 patients were treated with T-DXd. Among the 17 (26.6%) patients with reported SAEs, 10 (15.6%) had SAEs related to T-DXd treatment. Febrile neutropenia was the most common SAE (n = 6). SAEs led to death in six patients; drug-related SAEs (sepsis and febrile neutropenia) led to death in one patient. Drug-related ILD, as determined by the external Adjudication Committee, occurred in three patients (Grade 1, Grade 2, and Grade 3: all n = 1).

CONCLUSION

This expanded-access study provided T-DXd to a broader population of Japanese patients prior to marketing approval in Japan, bridging the gap between clinical trials and drug approval. No new safety concerns were identified.

Therapeutic target biomarkers of patient-derived xenograft models of gastric-type cervical adenocarcinoma

Background

Most cervical adenocarcinomas are associated with human papillomavirus (HPV). Gastric-type cervical adenocarcinoma (GAS), an HPV-independent adenocarcinoma, shows an aggressive clinical feature, resulting in a poor prognosis. Resistance to chemotherapy poses a difficulty in managing patients with metastatic GAS. We aimed to establish patient-derived xenografts (PDXs) of tumors from two patients with GAS and evaluated protein biomarkers for drug development using immunohistochemistry.

Methods

Two PDXs were established 78 and 48 days after transplanting the patient's tumor tissues into immunodeficient mice, respectively. PDX and patient's tumor samples were stained for HER2, HER3, PMS2, MSH6, PanTrk, and ARID1A to evaluate biomarkers for therapeutic targets. In addition, whole exome sequencing and RNA sequencing were performed on available samples.

Results

The pathological findings in morphological features and immunohistochemical profiles from the established PDXs were similar to those from the patients' surgical tumor specimens. HER3 was overexpressed in the patient's tumors, and the corresponding PDX tumors and HER2 was weakly stained in both types of tumor samples. In all PDX and patient tumor samples, PMS2, MSH6, and ARID1A were retained, and PanTrk was not expressed. In addition, a total of 10 samples, including tumor tissue samples from 8 other GAS patients, were evaluated for HER3 expression scores, all of which were 2 + or higher.

Conclusions

In summary, we evaluated biomarkers for therapeutic targets using newly established PDX models of GAS. Frequent HER3 overexpression and HER2 expression in GAS tumors suggest the possibility of new treatments for patients with GAS by targeting HER3 and HER2.

Comprehensive Analysis of Human Epidermal Growth Factor Receptor 2 Through DNA, mRNA, and Protein in Diverse Malignancies

PURPOSE

Human epidermal growth factor receptor 2 (HER2) expression (protein immunohistochemistry [IHC] or gene amplification [copy-number variation, CNV]) predicts anti-HER2 therapy responsiveness, although recently it was shown that even low HER2-expressing breast cancers benefit from trastuzumab-deruxtecan. Little is known about HER2 transcriptomic (mRNA) expression, and comparisons between genomic, mRNA, and protein HER2 assays.

METHODS

HER2 status was evaluated using clinical-grade IHC (protein), quantitative reverse transcription polymerase chain reaction (mRNA), and next-generation sequencing (NGS; amplifications).

RESULTS

Multi-institutional HER2 testing was performed on 5,305 diverse cancers including non-small-cell lung (n = 1,175), breast (n = 1,040), and colon cancers (n = 566; N = 3,926 tested for CNV; N = 1,848, mRNA; N = 2,533, IHC). Overall, 4.1% (161/3,926) had NGS HER2 amplification; 33.3% (615/1,848) had mRNA overexpression; and 9.3% (236/2,533) were IHC-positive. In 723 patients with all three tests (CNV/mRNA/IHC), various amplification/expression patterns occurred: 7.5% (54/723) had all three HER2 tests positive; 62.8% (454/723) had all three tests negative. Discrepant patterns between amplification and overexpression emerged. For instance, 20% (144/723) of patients had mRNA overexpression alone with negative CNV and IHC. A range in values for only mRNA+ cases occurred in different tumor types (eg, 16.9%, breast; 5%, hepatobiliary). There were 53 patients with various tumors from our institution who had all three assays attempted; 22 tested positive for HER2, and seven received anti-HER2 therapy: two patients achieved response: one (esophageal cancer), complete response (≥42 months); one (cholangiocarcinoma), who only had HER2 mRNA positivity (tissue was inadequate for IHC and CNV assessment), partial response (≥24 months) on HER2-based regimens.

CONCLUSION

We demonstrate variability of HER2 (protein and mRNA) expression and amplification using comprehensive assays (CNV, mRNA, and IHC) among diverse cancers. As HER2-targeted therapy indications expand, the relative importance of these modalities merits further evaluation.

The emergence of targeted therapy for HER2-low triple-negative breast cancer: a review of fam-trastuzumab deruxtecan

INTRODUCTION

Metastatic triple-negative breast cancer (TNBC) is an aggressive sub-type of breast cancer. Despite recent advances, metastatic TNBC remains difficult to treat with limited targeted treatment options. Fam-trastuzumab deruxtecan (T-DXd), is a novel antibody-drug conjugate (ADC) targeting human epidermal growth factor receptor 2 (HER2) and is composed of a unique linker bound to the topoisomerase I inhibitor DXd. T-DXd has significant anti-tumor activity in patients with HER2-low TNBC.

AREAS COVERED

This review reports on the mechanism, pre-clinical/clinical studies, efficacy, and tolerability of T-DXd. A literature search was conducted via PubMed using keywords such as 'fam-trastuzumab deruxtecan,' 'Enhertu,' and 'HER2-low cancers.'

EXPERT OPINION

The Phase III Destiny-Breast04 Trial showed benefit in progression-free and overall survival in patients with HER2-low metastatic breast cancers treated with T-DXd compared to treatment of physician's choice chemotherapy. T-DXd is the first pharmaceutical to effectively target a HER2-low population with clinically meaningful efficacy in patients with HER2-low TNBC. Compared to chemotherapy, T-DXd has a similar safety profile, with the additional need for close monitoring for interstitial lung disease. Given the clinical activity of T-DXd in TNBC, it is likely there will be continued efforts to refine HER2-low diagnostics and to develop additional ADCs with other protein targets.

Gallbladder cancer: current and future treatment options

Surgery remains the preferred treatment option for early-stage gallbladder cancer (GBC). According to the anatomical position of the primary tumor, accurate preoperative stage and strict control of surgical indications, appropriate surgical strategies are selected to achieve the optimal surgical effect. However, most patients have already been at the locally advanced stage or the tumor has metastasized at the initial diagnosis. The postoperative recurrence rate and 5-year survival rate remain unsatisfactory even after radical resection for gallbladder cancer. Hence, there is an urgent need for more treatment options, such as neoadjuvant therapy, postoperative adjuvant therapy and first-line and second-line treatments of local progression and metastasis, in the whole-course treatment management of gallbladder cancer patients. In recent years, the application of molecular targeted drugs and immunotherapy has brought greater hope and broader prospects for the treatment of gallbladder cancer, but their effects in improving the prognosis of patients still lack sufficient evidence-based medicine evidence, so many problems should be addressed by further research. Based on the latest progress in gallbladder cancer research, this review systematically analyzes the treatment trends of gallbladder cancer.

Prognostic biomarkers and molecular pathways mediating Helicobacter pylori–induced gastric cancer: a network-biology approach

Cancer of the stomach is the second most frequent cancer-related death worldwide. The survival rate of patients with gastric cancer (GC) remains fragile. There is a requirement to discover biomarkers for prognosis approaches. Helicobacter pylori in the stomach is closely associated with the progression of GC. We identified the genes associated with poor/favorable prognosis in H. pylori–induced GC. Multivariate statistical analysis was applied on the Gene Expression Omnibus (GEO) dataset GSE54397 to identify differentially expressed miRNAs (DEMs) in gastric tissues with H. pylori–induced cancer compared with the H. pylori–positive with non-cancerous tissue. A protein interaction map (PIM) was built and subjected to DEMs targets. The enriched pathways and biological processes within the PIM were identified based on substantial clusters. Thereafter, the most critical genes in the PIM were illustrated, and their prognostic impact in GC was investigated. Considering p-value less than 0.01 and |Log2 fold change| as >1, five microRNAs demonstrated significant changes among the two groups. Gene functional analysis revealed that the ubiquitination system, neddylation pathway, and ciliary process are primarily involved in H. pylori–induced GC. Survival analysis illustrated that the overexpression of DOCK4, GNAS, CTGF, TGF-b1, ESR1, SELE, TIMP3, SMARCE1, and TXNIP was associated with poor prognosis, while increased MRPS5 expression was related to a favorable prognosis in GC patients. DOCK4, GNAS, CTGF, TGF-b1, ESR1, SELE, TIMP3, SMARCE1, TXNIP, and MRPS5 may be considered prognostic biomarkers for H. pylori–induced GC. However, experimental validation is necessary in the future.

COMMD3-Mediated Endosomal Trafficking of HER2 Inhibits the Progression of Ovarian Carcinoma

The dysregulated endocytic traffic of oncogenic receptors, such as the EGFR family especially HER2, contributes to the uncontrolled activation of the downstream oncogenic signaling and progression of various carcinomas, including 90% of ovarian carcinoma. However, the key regulators in the intracellular trafficking of HER2 and their impacts for cancer progression remain largely unknown. In this study, through a genome-wide CRISPR/Cas9 screening for key genes affecting the peritoneal disseminated metastasis of ovarian carcinoma, we identified a member of COMMD family, that is, COMMD3, as a key regulator in the endosomal trafficking of HER2. In the patients with high-grade serous ovarian carcinoma (HGSOC), the expression of COMMD3 is dramatically decreased in the peritoneal disseminated ovarian carcinoma cells comparing with that in the primary ovarian carcinoma cells. COMMD3 greatly inhibits the proliferation, migration, and epithelial-mesenchymal transition (EMT) of HGSOC cells, and dramatically suppresses the tumor growth, the formation of malignant ascites, and the peritoneal dissemination of cancer cells in the orthotopic murine model of HGSOC. Further transcriptome analysis reveals that silencing COMMD3 boosts the activation of HER2 downstream signaling. As a component in the Retriever-associated COMMD/CCDC22/CCDC93 complex responsible for the recognition and recycling of membrane receptors, COMMD3 physically interacts with HER2 for directing it to the slow recycling pathway, leading to the attenuated downstream tumor-promoting signaling.

IMPLICATIONS

Collectively, this study reveals a novel HER2 inactivation mechanism with a high value for the clinic diagnosis of new ovarian carcinoma types and the design of new therapeutic strategy.

Molecular and functional imaging in cancer-targeted therapy: current applications and future directions

Targeted anticancer drugs block cancer cell growth by interfering with specific signaling pathways vital to carcinogenesis and tumor growth rather than harming all rapidly dividing cells as in cytotoxic chemotherapy. The Response Evaluation Criteria in Solid Tumor (RECIST) system has been used to assess tumor response to therapy via changes in the size of target lesions as measured by calipers, conventional anatomically based imaging modalities such as computed tomography (CT), and magnetic resonance imaging (MRI), and other imaging methods. However, RECIST is sometimes inaccurate in assessing the efficacy of targeted therapy drugs because of the poor correlation between tumor size and treatment-induced tumor necrosis or shrinkage. This approach might also result in delayed identification of response when the therapy does confer a reduction in tumor size. Innovative molecular imaging techniques have rapidly gained importance in the dawning era of targeted therapy as they can visualize, characterize, and quantify biological processes at the cellular, subcellular, or even molecular level rather than at the anatomical level. This review summarizes different targeted cell signaling pathways, various molecular imaging techniques, and developed probes. Moreover, the application of molecular imaging for evaluating treatment response and related clinical outcome is also systematically outlined. In the future, more attention should be paid to promoting the clinical translation of molecular imaging in evaluating the sensitivity to targeted therapy with biocompatible probes. In particular, multimodal imaging technologies incorporating advanced artificial intelligence should be developed to comprehensively and accurately assess cancer-targeted therapy, in addition to RECIST-based methods.

Advances in Molecular Regulation of Prostate Cancer Cells by Top Natural Products of Malaysia

Prostate cancer (PCa) remains both a global health burden and a scientific challenge. We present a review of the molecular targets driving current drug discovery to fight this disease. Moreover, the preventable nature of most PCa cases represents an opportunity for phytochemicals as chemopreventive when adequately integrated into nutritional interventions. With a renovated interest in natural remedies as a commodity and their essential role in cancer drug discovery, Malaysia is looking towards capitalizing on its mega biodiversity, which includes the oldest rainforest in the world and an estimated 1200 medicinal plants. We here explore whether the list of top Malay plants prioritized by the Malaysian government may fulfill the potential of becoming newer, sustainable sources of prostate cancer chemotherapy. These include Andrographis paniculate, Centella asiatica, Clinacanthus nutans, Eurycoma longifolia, Ficus deltoidea, Hibiscus sabdariffa, Marantodes pumilum (syn. Labisia pumila), Morinda citrifolia, Orthosiphon aristatus, and Phyllanthus niruri. Our review highlights the importance of resistance factors such as Smac/DIABLO in cancer progression, the role of the CXCL12/CXCR4 axis in cancer metastasis, and the regulation of PCa cells by some promising terpenes (andrographolide, Asiatic acid, rosmarinic acid), flavonoids (isovitexin, gossypin, sinensetin), and alkylresorcinols (labisiaquinones) among others.

TAS2940, a novel brain-penetrable pan-ERBB inhibitor, for tumors with HER2 and EGFR aberrations

Genetic alterations in human epidermal growth factor receptor type 2 (HER2)/epidermal growth factor receptor (EGFR) are commonly associated with breast and lung cancers and glioblastomas. Cancers with avian erythroblastosis oncogene B (ERBB) deregulation are highly metastatic and can cause primary brain tumors. Currently, no pan-ERBB inhibitor with remarkable brain penetration is available. Here, TAS2940, a novel irreversible pan-ERBB inhibitor with improved brain penetrability, was evaluated for its efficacy against several ERBB aberrant cancer models. The selectivity of TAS2940 was evaluated by enzymatic kinase assays. The inhibitory effects of TAS2940 against ERBB genetic alterations were examined using MCF10A cells expressing various HER2 or EGFR mutations and other generic cell lines harboring deregulated ERBB expression. In vivo efficacy of TAS2940 was examined following oral treatment in subcutaneous or intracranial xenograft cancer models. TAS2940 was highly potent against cells harboring HER2/EGFR alterations. TAS2940 could selectively inhibit phosphorylation of targets and the growth of cancer cells with ERBB aberrations in vitro. TAS2940 also inhibited tumor growth in xenograft mouse models with ERBB aberrations: HER2 amplification, HER2/EGFR exon 20 insertions, and EGFR vIII mutation. TAS2940 was effective in the intracranial xenograft models of HER2/EGFR cancers and improved the survival of these mice. TAS2940 has promising therapeutic effects in preclinical study against cancers harboring HER2/EGFR mutations, especially metastatic and primary brain tumors. Our results highlight potential novel strategies against lung cancers with brain metastases harboring HER2/EGFR exon 20 insertions and glioblastomas with EGFR aberrations.

The Role of Tumor-Associated Antigen HER2/neu in Tumor Development and the Different Approaches for Using It in Treatment: Many Choices and Future Directions

The treatment of HER2-positive cancers has changed significantly over the past ten years thanks to a significant number of promising new approaches that have been added to our arsenal in the fight against cancer, including monoclonal antibodies, inhibitors of tyrosine kinase, antibody-drug conjugates, vaccination, and particularly, adoptive-T-cell therapy after its great success in hematological malignancies. Equally important is the new methodology for determining patients eligible for targeted HER2 therapy, which has doubled the number of patients who can benefit from these treatments. However, despite the initial enthusiasm, there are still several problems in this field represented by drug resistance and tumor recurrence that require the further development of new more efficient drugs. In this review, we discuss various approaches for targeting the HER2 molecule in cancer treatment, highlighting their benefits and drawbacks, along with the different mechanisms responsible for resistance to HER2-targeted therapies and how to overcome them.

Direct In Vivo Comparison of 99mTc-Labeled Scaffold Proteins, DARPin G3 and ADAPT6, for Visualization of HER2 Expression and Monitoring of Early Response for Trastuzumab Therapy

Non-invasive radionuclide molecular visualization of human epidermal growth factor receptor type 2 (HER2) can provide stratification of patients for HER2-targeting therapy. This method can also enable monitoring of the response to such therapies, thereby making treatment personalized and more efficient. Clinical evaluation in a phase I study demonstrated that injections of two scaffold protein-based imaging probes, [^99mTc]Tc-(HE)₃-G3 and [^99mTc]Tc-ADAPT6, are safe, well-tolerated and cause a low level of radioactivity in healthy tissue. The goal of this preclinical study was to select the best probe for stratification of patients and response monitoring. Biodistribution of both tracers was compared in mice bearing SKOV-3 xenografts with high HER2 expression or MDA-MB-468 xenografts with very low expression. Changes in accumulation of the probes in SKOV-3 tumors 24 h after injection of trastuzumab were evaluated. Both [^99mTc]Tc-ADAPT6 and [^99mTc]Tc-(HE)₃-G3 permitted high contrast imaging of HER2-expressing tumors and a clear discrimination between tumors with high and low HER2 expression. However, [^99mTc]Tc-ADAPT6 has better preconditions for higher sensitivity and specificity of stratification. On the other hand, [^99mTc]Tc-(HE)₃-G3 is capable of detecting the decrease of HER2 expression on response to trastuzumab therapy only 24 h after injection of the loading dose. This indicates that the [^99mTc]Tc-(HE)₃-G3 tracer would be better for monitoring early response to such treatment. The results of this study should be considered in planning of further clinical development of HER2 imaging probes.

Comparative Preclinical Evaluation of Peptide-Based Chelators for the Labeling of DARPin G3 with 99mTc for Radionuclide Imaging of HER2 Expression in Cancer

Non-invasive radionuclide imaging of human epidermal growth factor receptor type 2 (HER2) expression in breast, gastroesophageal, and ovarian cancers may stratify patients for treatment using HER2-targeted therapeutics. Designed ankyrin repeat proteins (DARPins) are a promising type of targeting probe for radionuclide imaging. In clinical studies, the DARPin [99mTc]Tc-(HE)3-G3 labeled using a peptide-based chelator His-Glu-His-Glu-His-Glu ((HE)3), provided clear imaging of HER2 expressing breast cancer 2-4 h after injection. The goal of this study was to evaluate if the use of cysteine-containing peptide-based chelators Glu-Glu-Glu-Cys (E3C), Gly-Gly-Gly-Cys (G3C), and Gly-Gly-Gly-Ser-Cys connected via a (Gly-Gly-Gly-Ser)3-linker (designated as G3-(G3S)3C) would further improve the contrast of imaging using 99mTc-labeled derivatives of G3. The labeling of the new variants of G3 provided a radiochemical yield of over 95%. Labeled G3 variants bound specifically to human HER2-expressing cancer cell lines with affinities in the range of 1.9-5 nM. Biodistribution of [99mTc]Tc-G3-G3C, [99mTc]Tc-G3-(G3S)3C, and [99mTc]Tc-G3-E3C in mice was compared with the biodistribution of [99mTc]Tc-(HE)3-G3. It was found that the novel variants provide specific accumulation in HER2-expressing human xenografts and enable discrimination between tumors with high and low HER2 expression. However, [99mTc]Tc-(HE)3-G3 provided better contrast between tumors and the most frequent metastatic sites of HER2-expressing cancers and is therefore more suitable for clinical applications.

Pan-cancer gene expression analysis of tissue microarray using EdgeSeq oncology biomarker panel and a cross-comparison with HER2 and HER3 immunohistochemical analysis

Molecular and protein biomarker profiling are key to oncology drug development. Antibody-drug conjugates (ADCs) directly deliver chemotherapeutic agents into tumor cells based on unique cancer cell biomarkers. A pan-cancer tissue microarray (TMA) data set and gene panel were validated and gene signature analyses were conducted on normal and cancer tissues to refine selection of ADC targets. Correlation of mRNA and protein levels, and human epidermal growth factor receptor (HER) expression patterns were assessed. An EdgeSeq biomarker panel (2862 genes) was used across 8531 samples (23 solid cancer types/subtypes; 16 normal tissues) with an established TMA data set, and immune cell and cell cycle gene signatures were analyzed. Discriminating gene expression signatures were defined based on pathological classification of cancer subtypes. Correlative analyses of HER2 and HER3 mRNA (EdgeSeq) and protein expression (immunohistochemistry [IHC]) were performed and compared with publicly available data (The Cancer Genome Atlas [TCGA]; Cancer Cell Line Encyclopedia [CCLE]). Gene expression patterns among cancer types in the TMA (EdgeSeq) and TCGA (RNA-seq) were similar. EdgeSeq gene signature analyses aligned with the majority of pathological cancer types/subtypes and identified cancer-specific gene expression patterns. TMA IHC H-scores for HER3 varied across cancer types/subtypes. In a few cancer types, HER3 mRNA and protein expression did not align, including lower liver hepatocellular carcinoma IHC H-score, compared with mRNA. Although all TNBC and ovarian cancer subtypes expressed mRNA, some had lower protein expression. This was seen in TMA and TCGA data sets, but not in CCLE. The EdgeSeq TMA data set can expand upon current biomarker data by including cancers not currently in TCGA. The primary analysis of EdgeSeq and IHC comparison suggested a unique protein-level regulation of HER3 in some tumor subtypes and highlights the importance of investigating protein levels of ADC targets in both tumor and normal tissues.

NK cells with tissue-resident traits shape response to immunotherapy by inducing adaptive antitumor immunity

T cell–directed cancer immunotherapy often fails to generate lasting tumor control. Harnessing additional effectors of the immune response against tumors may strengthen the clinical benefit of immunotherapies. Here, we demonstrate that therapeutic targeting of the interferon-γ (IFN-γ)–interleukin-12 (IL-12) pathway relies on the ability of a population of natural killer (NK) cells with tissue-resident traits to orchestrate an antitumor microenvironment. In particular, we used an engineered adenoviral platform as a tool for intratumoral IL-12 immunotherapy (AdV5–IL-12) to generate adaptive antitumor immunity. Mechanistically, we demonstrate that AdV5–IL-12 is capable of inducing the expression of CC-chemokine ligand 5 (CCL5) in CD49a + NK cells both in tumor mouse models and tumor specimens from patients with cancer. AdV5–IL-12 imposed CCL5-induced type I conventional dendritic cell (cDC1) infiltration and thus increased DC-CD8 T cell interactions. A similar observation was made for other IFN-γ–inducing therapies such as Programmed cell death 1 (PD-1) blockade. Conversely, failure to respond to IL-12 and PD-1 blockade in tumor models with low CD49a + CXCR6 + NK cell infiltration could be overcome by intratumoral delivery of CCL5. Thus, therapeutic efficacy depends on the abundance of NK cells with tissue-resident traits and, specifically, their capacity to produce the DC chemoattractant CCL5. Our findings reveal a barrier for T cell–focused therapies and offer mechanistic insights into how T cell–NK cell–DC cross-talk can be enhanced to promote antitumor immunity and overcome resistance.

Discovery of potent and selective HER2 inhibitors with efficacy against HER2 exon 20 insertion-driven tumors, which preserve wild-type EGFR signaling

Oncogenic alterations in human epidermal growth factor receptor 2 (HER2) occur in approximately 2% of patients with non-small cell lung cancer and predominantly affect the tyrosine kinase domain and cluster in exon 20 of the ERBB2 gene. Most clinical-grade tyrosine kinase inhibitors are limited by either insufficient selectivity against wild-type (WT) epidermal growth factor receptor (EGFR), which is a major cause of dose-limiting toxicity or by potency against HER2 exon 20 mutant variants. Here we report the discovery of covalent tyrosine kinase inhibitors that potently inhibit HER2 exon 20 mutants while sparing WT EGFR, which reduce tumor cell survival and proliferation in vitro and result in regressions in preclinical xenograft models of HER2 exon 20 mutant non-small cell lung cancer, concomitant with inhibition of downstream HER2 signaling. Our results suggest that HER2 exon 20 insertion-driven tumors can be effectively treated by a potent and highly selective HER2 inhibitor while sparing WT EGFR, paving the way for clinical translation.

Advances in Diagnosis and Therapy for Bladder Cancer

Simple Summary

The clinical management of bladder cancer has been developing in the past decade, including diagnostic tools and treatment options. Both monotherapy and combination therapy have been undoubtedly upgraded. Multiple diagnostic techniques and therapeutic strategies have been developed to meet the urgent clinical needs, resulting in the emergence of various explorations for cancer diagnosis and therapy. In this review, we mainly focus on the advances in the diagnosis and treatment of bladder cancer.

Abstract

Bladder cancer (BCa) is one of the most common and expensive urinary system malignancies for its high recurrence and progression rate. In recent years, immense amounts of studies have been carried out to bring a more comprehensive cognition and numerous promising clinic approaches for BCa therapy. The development of innovative enhanced cystoscopy techniques (optical techniques, imaging systems) and tumor biomarkers-based non-invasive urine screening (DNA methylation-based urine test) would dramatically improve the accuracy of tumor detection, reducing the risk of recurrence and progression of BCa. Moreover, intravesical instillation and systemic therapeutic strategies (cocktail therapy, immunotherapy, vaccine therapy, targeted therapy) also provide plentiful measures to break the predicament of BCa. Several exploratory clinical studies, including novel surgical approaches, pharmaceutical compositions, and bladder preservation techniques, emerged continually, which are supposed to be promising candidates for BCa clinical treatment. Here, recent advances and prospects of diagnosis, intravesical or systemic treatment, and novel drug delivery systems for BCa therapy are reviewed in this paper.

Serum ErbB2 concentration positively correlated to the glycemic variations in newly diagnosed Type 2 diabetic patients

Evidences indicate that elevated levels of circulating ErbB2 are closely associated with increased incidence of diabetes. However, the relationship between ErbB2 concentration and glycemic variations (GV) in type 2 diabetic (T2D) patients remains elucidated. The aim of this study was to assess whether there is an association between serum ErbB2 concentration and GV in newly diagnosed T2D patients. This was a three-center, and observational study. Between April 2019 and July 2019, a total of 106 newly diagnosed T2D patients were recruited. All recruited subjects were admitted as inpatients and received anti-diabetes agents free during the study period. At baseline, fasting serum was collected for ErbB2 measurement and all recruited patients were subjected a prospective CGM for at least 3 days. The primary endpoint was the relationships between ErbB2 concentrations and GV in T2D patients. Data of a total of 95 subjects who met the inclusion criteria were analyzed at the endpoint. Subjects were divided into quartiles according to their serum ErbB2 concentrations. We observed that subjects with an elevated level of ErbB2 had a higher value of GV in terms of mean amplitude of glucose excursion (MAGE), standard deviation of mean glucose (SDMG), and the coefficient of variation (CV%) than those with lower levels (all P < 0.05). Multiple linear regression analyzes after adjusting for confounder factors indicate that serum ErbB2 levels were significantly positively correlated with the MAGE (β = 0.664, t = 7.218, P < 0.01), SD (β = 0.469, t = 5.125, P < 0.01) and CV% (β = 0.337, t = 4.442, P < 0.01), respectively. Our data indicated that diabetic patients with higher ErbB2 concentrations may have large GV, which is an independent risk factor for microvascular and macrovascular complications.

Efficacy of Disitamab Vedotin in Treating HER2 2+/FISH- Gastric Cancer

Currently, effective therapies for advanced gastric cancer with systemic metastasis are lacking. Pharmacological research has been slowly progressing over the past decades. Here, we report the case of a 56-year-old female with human epidermal growth factor receptor 2 (HER2) expression (IHC 2+/FISH-) in gastric cancer with systemic metastasis. The first-line therapeutic regime consisted of systemic administration of camrelizumab, local arterial infusion of oxaliplatin and arterial embolization, oral apatinib, and PS scheme (oral tegafur-gimeracil-oteracil (S-1) and paclitaxel (PTX), which was administered both intraperitoneally and systemically). After the treatment, a 3-month progression-free survival (PFS) was observed. Due to the occurrence of CTCAE grade 4 adverse reactions, the patient could not tolerate chemotherapy. In the second line of treatment, we replaced the PS scheme with disitamab vedotin and continued the use of carrilizumab and apatinib. After four cycles, efficacy evaluation showed that it was stable disease (SD), only CTCAE 1/2 grade adverse reactions occurred, and endoscopy examination showed local tumor control with a reduction in the ulcer lesion. At the time of submission of the current manuscript, a 6-month PFS was achieved and the treatment was continued. Due to the safety and efficacy of disitamab vedotin observed in our case, we propose that disitamab vedotin could be a promising drug for the treatment of advanced gastric cancer patients with HER2 expression.

Pertuzumab Cardiotoxicity in Patients With HER2-Positive Cancer: A Systematic Review and Meta-analysis

Background

Human epidermal growth factor receptor 2 (HER2) overexpressing malignancies, including breast and gastro-esophageal, are associated with a poor prognosis. The cardiotoxicity of trastuzumab, a HER2-targeting monoclonal antibody, is well established. However, the cardiotoxic effect of pertuzumab, another HER2-directed therapy, is less well documented. The objective of this systematic review and meta-analysis was to determine the risk of cardiac events in patients with HER2-positive cancer who are receiving pertuzumab.

Methods

We performed a systematic review of phase 2 and 3 randomized controlled trials in which the addition of pertuzumab to other standard therapies in patients with stage I-IV HER2-positive cancer was evaluated, and cardiac adverse effects reported. We searched MEDLINE (1946-2020), Embase (1974-2020), and CENTRAL. Two independent reviewers assessed the risk of bias and extracted the data. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated from the pooled data using the inverse variance method and random-effects models.

Results

Eight randomized controlled trials (8420 patients) were included: 1 was gastro-esophageal; 7 were breast cancer trials. Participants’ median age ranged from 49 to 61.5 years. All participants received trastuzumab and chemotherapy in addition to pertuzumab or placebo. Compared with placebo, pertuzumab increased the risk of clinical heart failure (HF; RR [95% CI]: 1.97 [1.05-3.70]; I² = 0%). However, pertuzumab had no demonstrable effect on asymptomatic/minimally symptomatic left ventricular systolic dysfunction (RR [95% CI]: 1.19 [0.89-1.61]; I² = 19%).

Conclusions

Pertuzumab increases the risk of clinical HF, but not asymptomatic/minimally symptomatic left ventricular systolic dysfunction, in HER2-positive cancer patients. Further research into the mechanisms underlying pertuzumab-related HF is needed to understand its clinical spectrum of cardiotoxicity.

Molecular characterization of squamous cell carcinoma of the anal canal

Background

Squamous cell carcinoma of the anal canal (SCCA) is an uncommon malignancy with limited therapeutic options. Nivolumab and pembrolizumab show promising results in patients with SCCA. Human papillomavirus (HPV)-negative tumors are frequently TP53-mutated (TP53-MT) and often resistant to therapy.

Methods

We present a large molecularly-profiled cohort of SCCA, exploring the underlying biology of SCCA, differences between TP53-wild type (TP53-WT) and TP53-MT tumors, and differences between local and metastatic tumors. SCCA specimens (n=311) underwent multiplatform testing with immunohistochemistry (IHC), in situ hybridization (ISH) and next-generation sequencing (NGS). Tumor mutational burden (TMB) was calculated using only somatic nonsynonymous missense mutations. Chi-square testing was used for comparative analyses.

Results

The most frequently mutated genes included PIK3CA (28.1%), KMT2D (19.5%), FBXW7 (12%), TP53 (12%) and PTEN (10.8%). The expression of PD-1 was seen in 68.8% and PD-L1 in 40.5% of tumors. High TMB was present in 6.7% of specimens. HER2 IHC was positive in 0.9%, amplification by chromogenic in situ hybridization (CISH) was seen 1.3%, and mutations in ERBB2 were present in 1.8% of tumors. The latter mutation has not been previously described in SCCA. When compared with TP53-WT tumors, TP53-MT tumors had higher rates of CDKN2A, EWSR1, JAK1, FGFR1 and BRAF mutations. PD-1 and PD-L1 expression were similar, and high TMB did not correlate with PD-1 (P=0.50) or PD-L1 (P=0.52) expression.

Conclusions

Molecular profiling differences between TP53-MT and TP53-WT SCCA indicate different carcinogenic pathways which may influence response to therapy. Low frequency mutations in several druggable genes may provide therapeutic opportunities for patients with SCCA.

Antibody drug conjugates in gastrointestinal cancer: From lab to clinical development

The antibody-drug conjugates (ADCs) are one the fastest growing biotherapeutics in oncology and are still in their infancy in gastrointestinal (GI) cancer for clinical applications to improve patient survival. The ADC based approach is developed with tumor specific antigen, antibody carrying cytotoxic agents to precisely target and deliver chemotherapeutics at the tumor site. To date, 11 ADCs have been approved by US-FDA, and more than 80 are in the clinical development phase for different oncological indications. However, The ADCs based therapies in GI cancers are still far from having high-efficient clinical outcomes. The limited success of these ADCs and lessons learned from the past are now being used to develop a newer generation of ADC against GI cancers. In this review, we did a comprehensive assessment of the key components of ADCs, including tumor marker, antibody, cytotoxic payload, and linkage strategy, with a focus on technical improvement and some future trends in the pipeline for clinical translation. The various preclinical and clinical ADCs used in gastrointestinal malignancies, their target, composition and bioconjugation, along with preclinical and clinical outcomes, are discussed. The emphasis is also given to new generation ADCs employing novel mAb, payload, linker, and bioconjugation methods are also included.

Preclinical evaluation of MRG002, a novel HER2-targeting antibody-drug conjugate with potent antitumor activity against HER2-positive solid tumors

Background

ERBB2 is a proto-oncogene of multiple cancers including breast and gastric cancers with HER2 protein overexpression or gene amplification and has been proven clinically as a valid target for these cancers. HER2-targeting agents such as Herceptin®, Kadcyla® and ENHERTU® have been approved by the FDA for the treatment of breast cancer, but these drugs still face the challenge of acquired resistance and/or severe adverse reactions in clinical use. Therefore, there is significant unmet medical need for developing new agents that are more effective and safer for patients with advanced HER2-positive solid tumors including breast and gastric cancers.

Methods

We report here the making of MRG002, a novel HER2-targeted antibody drug conjugate (ADC), and preclinical characterization including pharmacology, pharmacodynamics and toxicology and discuss its potential as a novel agent for treating patients with HER2-positive solid tumors.

Results

MRG002 exhibited similar antigen binding affinity but much reduced antibody-dependent cellular cytotoxicity (ADCC) activity compared to trastuzumab. In addition to potent in vitro cytotoxicity, MRG002 showed tumor regression in both high- and medium-to-low HER2 expressing in vivo xenograft models. Furthermore, MRG002 showed enhanced antitumor activity when used in combination with an anti-PD-1 antibody. Main findings from toxicology studies are related to the payload and are consistent with literature report of other ADCs with monomethyl auristatinE.

Conclusion

MRG002 has demonstrated a favorable toxicity profile and potent antitumor activities in the breast and gastric PDX models with varying levels of HER2 expression, and/or resistance to trastuzumab or T-DM1. A phase I clinical study of MRG002 in patients with HER2-positive solid tumors is ongoing (CTR20181778).

A randomized, double-blind, single-dose study (LAVENDER) to assess the safety, tolerability, pharmacokinetics, and immunogenicity of a combined infusion of ABP 980 and pertuzumab in healthy subjects

PURPOSE

ABP 980 (KANJINTI^™) is a biosimilar to reference product HERCEPTIN^® (trastuzumab RP). The goal of this study was to characterize the safety, tolerability, and immunogenicity of ABP 980 plus pertuzumab (PERJETA^®) when co-administered in a single infusion bag in healthy subjects.

METHODS

This randomized, double-blind, single-dose, 2-arm, parallel-group study (LAVENDER Study) evaluated an intravenous (IV) infusion of ABP 980 (6 mg/kg) plus pertuzumab (420 mg) combined in a single infusion bag relative to an IV infusion of trastuzumab RP (6 mg/kg) plus pertuzumab (420 mg) combined in a single infusion bag given over 60 min. The subjects were followed for 92 days post dosing.

RESULTS

A total of 42 subjects were enrolled in the study and treated with investigational product. Due to an operational issue during dosing, the first 6 subjects enrolled in the study were replaced. A total of 36 randomized subjects, n = 18 for ABP 980 plus pertuzumab and n = 18 for trastuzumab RP plus pertuzumab, were treated. Resulting serum concentrations of ABP 980 and trastuzumab RP were similar. There were no serious adverse events, no deaths, and no cardiac disorders during the study. No subject developed anti-drug antibodies throughout the study.

CONCLUSIONS

This study demonstrated the safety and tolerability of ABP 980 and pertuzumab admixture in a single infusion bag. The safety profiles and pharmacokinetic parameters of ABP 980 and pertuzumab were consistent with what is known for trastuzumab RP and pertuzumab.

CLINICAL TRIAL LISTING

EudraCT 2018-002903-33.

Multi-Gene Testing Overview with a Clinical Perspective in Metastatic Triple-Negative Breast Cancer

Next-generation sequencing (NGS) is the technology of choice for the routine screening of tumor samples in clinical practice. In this setting, the targeted sequencing of a restricted number of clinically relevant genes represents the most practical option when looking for genetic variants associated with cancer, as well as for the choice of targeted treatments. In this review, we analyze available NGS platforms and clinical applications of multi-gene testing in breast cancer, with a focus on metastatic triple-negative breast cancer (mTNBC). We make an overview of the clinical utility of multi-gene testing in mTNBC, and then, as immunotherapy is emerging as a possible targeted therapy for mTNBC, we also briefly report on the results of the latest clinical trials involving immune checkpoint inhibitors (ICIs) and TNBC, where NGS could play a role for the potential predictive utility of homologous recombination repair deficiency (HRD) and tumor mutational burden (TMB).

Targeting human epidermal growth factor receptor 2 (HER2) in gynecologic malignancies

PURPOSE OF REVIEW

The purpose of this review is to describe the role of the human epidermal growth factor receptor 2 (HER2) as a biomarker and potential target in gynecologic malignancies and to describe contemporary updates in the use of anti-HER2 treatments for these cancers.

RECENT FINDINGS

Approximately 25-30% of all patients with uterine serous carcinoma overexpress tumoral HER2. The anti-HER2 antibody trastuzumab represents an effective, targeted therapy with significant efficacy in the treatment of HER2-positive breast and gastric cancer. Recently, trastuzumab efficacy has also been demonstrated in a randomized controlled trial of women with advanced or recurrent uterine serous carcinoma. Additionally, trastuzumab may be effective in women with HER2-positive uterine carcinosarcoma. The role of anti-HER2 therapy is unclear in women with other gynecologic malignancies but is being evaluated.

SUMMARY

HER2 amplification/overexpression is an effective therapeutic target in select gynecologic malignancies, and especially in the rare endometrial cancer subtype, uterine serous carcinoma. As anti-HER2-targeted therapies become increasingly available, more treatment options may become available for women with HER2-positive disease.

Exploiting somatic alterations as therapeutic targets in advanced and metastatic cervical cancer

It is estimated that 604,127 patients were diagnosed with cervical cancer worldwide in 2020. While a small percentage of patients will have metastatic disease at diagnosis, a large percentage (15-61%) later develop advanced disease. For this cohort, treatment with systemic chemotherapy remains the standard of care, with a static 5-year survival rate over the last thirty years. Data on targetable molecular alterations in cervical cancer have lagged behind other more common tumor types thus stunting the development of targeted agents. In recent years, tumor genomic testing has been increasingly incorporated into our clinical practice, opening the door for a potential new era of personalized treatment for advanced cervical cancer. The interim results from the NCI-MATCH study reported an actionability rate of 28.4% for the cervical cancer cohort, suggesting a subset of patients may harbor mutations which that are targetable. This review sets out to summarize the key targeted agents currently under exploration either alone or in combination with existing treatments for cervical cancer.

Immunomodulatory Factors in Primary Endometrial Cell Cultures Isolated from Cancer and Noncancerous Human Tissue-Focus on RAGE and IDO1

Background: Immune modulatory factors like indoleamine 2,3-dioxygenase 1 (IDO1) generating kynurenine (Kyn) and receptor for advanced glycation end-products (RAGE) contribute to endometrial and cancer microenvironment. Using adequate experimental models is needed to learn about the significance of these molecular factors in endometrial biology. In this paper we study IDO1 activity and RAGE expression in the in vitro cultured primary human endometrial cells derived from cancerous and noncancerous tissue. Methods: The generated primary cell cultures from cancer and noncancerous endometrial tissues were characterized using immunofluorescence and Western Blot for expression of endometrial and cancer markers. IDO1 activity was studied by Kyn quantification with High Performance Liquid Chromatography with Diode Array Detector. Results: The primary cultures of endometrial cells were obtained with 80% success rate and no major genetic aberrations. The cells retained in vitro expression of markers (mucin MUC1 and HER2) or immunomodulatory factors (RAGE and IDO1). Increased Kyn secretion was associated with cancer endometrial cell culture in contrast to the control one. Conclusions: Primary endometrial cells express immune modulatory factors RAGE and IDO1 in vitro associated with cancer phenotype of endometrium.

The Clinical Value of VDR and CTLA 4 in Evaluating the Prognosis of Invasive Duct Carcinoma of Egyptian Patients and their Benefit as a Target Therapy

OBJECTIVE

Breast cancer represents the second most common female malignancies worldwide  and  the most common in Egypt. The nuclear vitamin D receptor plays a role in the biology of cancer by affecting inflammatory microenvironment. The aim of this study is to evaluate the role of VDR and CTLA 4 in invasive duct carcinoma of Egyptian patients.

METHODS

This is a retrospective study that included 70 invasive duct carcinoma specimens retrieved from the archival material of Pathology Department, Faculty of medicine, Menoufia University, Egypt, spanning the period between January 2010 and December 2017. All cases were stained for VDR and CTLA 4 antibodies.

RESULTS

There is significant association between high VDR expression in tumor cells and parameters of good prognosis as low tumor stage (T1) and (N0) stage. On the other hand, there is significant association between low CTLA4 tumor expression and good prognostic parameters as low tumor stage (T1) and absent vascular invasion. Regarding lymphocyte expression, there is significant association between positive CTLA4 expression in lymphocytes and parameters of good prognosis as absent metastasis. High VDR tumor expression is the most independent prognostic factor on overall survival of breast carcinoma patients.

CONCLUSION

high VDR expression in tumor cells is associated with good prognostic parameters and is the most independent prognostic factor on overall survival  so it might be of benefit as a target therapy for Egyptian invasive duct carcinoma patients and VDR might augment the expression of CTLA-4, So tailored  immunotherapy might have an impact on invasive duct carcinoma patients.<br />.

An Integrative Computational Approach Based on Expression Similarity Signatures to Identify Protein-Protein Interaction Networks in Female-Specific Cancers

Breast, ovarian, and endometrial cancers have a major impact on mortality in women. These tumors share hormone-dependent mechanisms involved in female-specific cancers which support tumor growth in a different manner. Integrated computational approaches may allow us to better detect genomic similarities between these different female-specific cancers, helping us to deliver more sophisticated diagnosis and precise treatments. Recently, several initiatives of The Cancer Genome Atlas (TCGA) have encouraged integrated analyses of multiple cancers rather than individual tumors. These studies revealed common genetic alterations (driver genes) even in clinically distinct entities such as breast, ovarian, and endometrial cancers. In this study, we aimed to identify expression similarity signatures by extracting common genes among TCGA breast (BRCA), ovarian (OV), and uterine corpus endometrial carcinoma (UCEC) cohorts and infer co-regulatory protein-protein interaction networks that might have a relationship with the estrogen signaling pathway. Thus, we carried out an unsupervised principal component analysis (PCA)-based computational approach, using RNA sequencing data of 2,015 female cancer and 148 normal samples, in order to simultaneously capture the data heterogeneity of intertumors. Firstly, we identified tumor-associated genes from gene expression profiles. Secondly, we investigated the signaling pathways and co-regulatory protein-protein interaction networks underlying these three cancers by leveraging the Ingenuity Pathway Analysis software. In detail, we discovered 1,643 expression similarity signatures (638 downregulated and 1,005 upregulated genes, with respect to normal phenotype), denoted as tumor-associated genes. Through functional genomic analyses, we assessed that these genes were involved in the regulation of cell-cycle-dependent mechanisms, including metaphase kinetochore formation and estrogen-dependent S-phase entry. Furthermore, we generated putative co-regulatory protein-protein interaction networks, based on upstream regulators such as the ERBB2/HER2 gene. Moreover, we provided an ad-hoc bioinformatics workflow with a manageable list of intertumor expression similarity signatures for the three female-specific cancers. The expression similarity signatures identified in this study might uncover potential estrogen-dependent molecular mechanisms promoting carcinogenesis.

A bivalent, bispecific Dab-Fc antibody molecule for dual targeting of HER2 and HER3

Dual targeting of surface receptors with bispecific antibodies is attracting increasing interest in cancer therapy. Here, we present a novel bivalent and bispecific antagonistic molecule (Dab-Fc) targeting human epidermal growth factors 2 and 3 (HER2 and HER3) derived from the Db-Ig platform, which was developed for the generation of multivalent and multispecific antibody molecules. Dab-Fc comprises the variable domains of the anti-HER2 antibody trastuzumab and the anti-HER3 antibody 3-43 assembled into a diabody-like structure stabilized by CH1 and CL domains and further fused to a human γ1 Fc region. The resulting Dab-Fc 2 × 3 molecule retained unhindered binding to both antigens and was able to bind both antigens sequentially. In cellular experiments, the Dab-Fc 2 × 3 molecule strongly bound to different tumor cell lines expressing HER2 and HER3 and was efficiently internalized. This was associated with potent inhibition of the proliferation and migration of these tumor cell lines. Furthermore, IgG-like pharmacokinetics and anti-tumoral activity were demonstrated in a xenograft tumor model of the gastric cancer cell-line NCI-N87. These results illustrate the suitability of our versatile Db-Ig platform technology for the generation of bivalent bispecific molecules, which has been successfully used here for the dual targeting of HER2 and HER3.

An analysis of HER2 amplification in cervical adenocarcinoma: correlation with clinical outcomes and the International Endocervical Adenocarcinoma Criteria and Classification

Few studies have explored HER2 status in cervical adenocarcinoma, particularly in the gastric-type adenocarcinoma (GAC), a nonhuman-papillomavirus-related subtype with poor clinical outcomes. In this study, we investigated HER2 expression and amplification by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in 209 well annotated cervical adenocarcinomas diagnosed using the International Endocervical Adenocarcinoma Criteria and Classification. IHC identified HER2 protein expression in 57.4% (123/209) of adenocarcinomas, of which 62 were IHC 1+ (negative), 38 2+ (equivocal) and 23 3+ (positive). HER2 amplification was found in 13 cases (6.2%) including 10 with IHC 3+ and 3 with IHC 2+. Among all the major histotypes of cervical adenocarcinoma, HER2 amplification was most common in GAC cases with a frequency of 14.7% (5/34). Moreover, HER2 amplification was more frequently associated with 2018 International Federation of Gynecology & Obstetrics (FIGO) stage III/IV, perineural involvement and ovarian spread (p < 0.05) while IHC 3+ was more common in patients with lymphovascular invasion and ovarian involvement (p < 0.05). Survival analysis indicated that FIGO stage III/IV, GAC, and p53 overexpression were associated with poor disease-specific survival and tumor recurrence (p < 0.05). In conclusion, HER2 amplification was present in a subset of adenocarcinomas, and more common in GAC, pointing to a potential benefit from trastuzumab treatment. HER2 overexpression does not identify gene amplification status in cervical adenocarcinoma; therefore, FISH is suggested for both IHC positive and equivocal cases. Further investigation on more cases with longer follow-up times is required to consolidate these findings.

Immunomodulatory activity of IR700-labelled affibody targeting HER2

There is an urgent need to develop therapeutic approaches that can increase the response rate to immuno-oncology agents. Photoimmunotherapy has recently been shown to generate anti-tumour immunological responses by releasing tumour-associated antigens from ablated tumour cell residues, thereby enhancing antigenicity and adjuvanticity. Here, we investigate the feasibility of a novel HER2-targeted affibody-based conjugate (Z_HER2:2395-IR700) selectively to induce cancer cell death in vitro and in vivo. The studies in vitro confirmed the specificity of Z_HER2:2395-IR700 binding to HER2-positive cells and its ability to produce reactive oxygen species upon light irradiation. A conjugate concentration- and light irradiation-dependent decrease in cell viability was also demonstrated. Furthermore, light-activated Z_HER2:2395-IR700 triggered all hallmarks of immunogenic cell death, as defined by the translocation of calreticulin to the cell surface, and the secretion of ATP, HSP70/90 and HMGB1 from dying cancer cells into the medium. Irradiating a co-culture of immature dendritic cells (DCs) and cancer cells exposed to light-activated Z_HER2:2395-IR700 enhanced DC maturation, as indicated by augmented expression of CD86 and HLA-DR. In SKOV-3 xenografts, the Z_HER2:2395-IR700-based phototherapy delayed tumour growth and increased median overall survival. Collectively, our results strongly suggest that Z_HER2:2395-IR700 is a promising new therapeutic conjugate that has great potential to be applicable for photoimmunotherapy-based regimens.

Attenuation of p53 mutant as an approach for treatment Her2-positive cancer

Breast cancer is one of the world's leading causes of oncological disease-related death. It is characterized by a high degree of heterogeneity on the clinical, morphological, and molecular levels. Based on molecular profiling breast carcinomas are divided into several subtypes depending on the expression of a number of cell surface receptors, e.g., ER, PR, and HER2. The Her2-positive subtype occurs in ~10-15% of all cases of breast cancer, and is characterized by a worse prognosis of patient survival. This is due to a high and early relapse rate, as well as an increased level of metastases. Several FDA-approved drugs for the treatment of Her2-positive tumors have been developed, although eventually cancer cells develop drug resistance. These drugs target either the homo- or heterodimerization of Her2 receptors or the receptors' RTK activity, both of them being critical for the proliferation of cancer cells. Notably, Her2-positive cancers also frequently harbor mutations in the TP53 tumor suppressor gene, which exacerbates the unfavorable prognosis. In this review, we describe the molecular mechanisms of RTK-specific drugs and discuss new perspectives of combinatorial treatment of Her2-positive cancers through inhibition of the mutant form of p53.

Preparation and characterization of antibody-drug conjugates acting on HER2-positive cancer cells

Two systems of antibody-drug conjugates (ADCs), noncleavable H32-DM1 and cleavable H32-VCMMAE, were developed by using different linkers and drugs attached to the anti-HER2 antibody H32, which is capable of cell internalization. Activated functional groups, including an N-hydroxysuccinimidyl (NHS) ester and a maleimide, were utilized to make the ADCs. Mass spectrometry, hydrophobic interaction chromatography, polyacrylamide gel electrophoresis, and in vitro cell assays were performed to analyze and optimize the ADCs. Several H32-VCMMAE ADCs were established with higher DARs and greater synthetic yields without compromising potency. The anticancer efficacy of H32-DM1 was 2- to 8-fold greater than that of Kadcyla^®. The efficacy of H32-VCMMAE was in turn better than that of H32-DM1. The anticancer efficacy of these ADCs against N87, SK-BR-3 and BT474 cells was in the following order: H32-VCMMAE series > H32-DM1 series > Kadcyla^®. The optimal DAR for H32-VCMMAE was found to be 6.6, with desirable attributes including good cell penetration, a releasable payload in cancer cells, and high potency. Our results demonstrated the potential of H32-VCMMAE as a good ADC candidate.

Unraveling ERBB network dynamics upon betacellulin signaling in pancreatic ductal adenocarcinoma in mice

Pancreatic ductal adenocarcinoma (PDAC) will soon belong to the top three cancer killers. The only approved specific PDAC therapy targets the epidermal growth factor receptor (EGFR). Although EGFR is a crucial player in PDAC development, EGFR-based therapy is disappointing. In this study, we evaluated the role of the EGFR ligand betacellulin (BTC) in PDAC. The expression of BTC was investigated in human pancreatic cancer specimen. Then, we generated a BTC knockout mouse model by CRISPR/Cas9 technology and a BTC overexpression model. Both models were crossed with the Ptf1aCre/+ ;KRASG12D/+ (KC) mouse model (B-/- KC or BKC, respectively). In addition, EGFR, ERBB2, and ERBB4 were investigated by the pancreas-specific deletion of each receptor using the Cre-loxP system. Tumor initiation and progression were analyzed in all mouse lines, and the underlying molecular biology of PDAC was investigated at different time points. BTC is expressed in human and murine PDAC. B-/- KC mice showed a decelerated PDAC progression, associated with decreased EGFR activation. BKC mice developed severe PDAC with a poor survival rate. The dramatically increased BTC-mediated tumor burden was EGFR-dependent, but also ERBB4 and ERBB2 were involved in PDAC development or progression, as depletion of EGFR, ERBB2, or ERBB4 significantly improved the survival rate of BTC-mediated PDAC. BTC increases PDAC tumor burden dramatically by enhanced RAS activation. EGFR signaling, ERBB2 signaling, and ERBB4 signaling are involved in accelerated PDAC development mediated by BTC indicating that targeting the whole ERBB family, instead of a single receptor, is a promising strategy for the development of future PDAC therapies.

NIR Photodynamic Destruction of PDAC and HNSCC Nodules Using Triple-Receptor-Targeted Photoimmuno-Nanoconjugates: Targeting Heterogeneity in Cancer

Receptor heterogeneity in cancer is a major limitation of molecular targeting for cancer therapeutics. Single-receptor-targeted treatment exerts selection pressures that result in treatment escape for low-receptor-expressing tumor subpopulations. To overcome this potential for heterogeneity-driven resistance to molecular targeted photodynamic therapy (PDT), we present for the first time a triple-receptor-targeted photoimmuno-nanoconjugate (TR-PIN) platform. TR-PIN functionalization with cetuximab, holo-transferrin, and trastuzumab conferred specificity for epidermal growth factor receptor (EGFR), transferrin receptor (TfR), and human epidermal growth factor receptor 2 (HER-2), respectively. The TR-PINs exhibited up to a 24-fold improvement in cancer cell binding compared with EGFR-specific cetuximab-targeted PINs (Cet-PINs) in low-EGFR-expressing cell lines. Photodestruction using TR-PINs was significantly higher than the monotargeted Cet-PINs in heterocellular 3D in vitro models of heterogeneous pancreatic ductal adenocarcinoma (PDAC; MIA PaCa-2 cells) and heterogeneous head and neck squamous cell carcinoma (HNSCC, SCC9 cells) containing low-EGFR-expressing T47D (high TfR) or SKOV-3 (high HER-2) cells. Through their capacity for multiple tumor target recognition, TR-PINs can serve as a unique and amenable platform for the effective photodynamic eradication of diverse tumor subpopulations in heterogeneous cancers to mitigate escape for more complete and durable treatment responses.

Neratinib in patients with HER2-mutant, metastatic cervical cancer: Findings from the phase 2 SUMMIT basket trial

OBJECTIVE

Somatic HER2 mutations occur in ~5% of cervical cancers and are considered oncogenic and associated with poor prognosis. Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, is active in multiple HER2-mutant cancers. SUMMIT is a phase II basket trial investigating the efficacy and safety of neratinib in solid tumors.

METHODS

Patients with HER2-mutant, persistent, metastatic/recurrent cervical cancer with disease progression after platinum-based treatment for advanced/recurrent disease received oral neratinib 240 mg/day with mandatory loperamide prophylaxis during cycle 1. The primary endpoint was confirmed objective response rate (ORR). Secondary endpoints included: response duration (DOR); clinical benefit rate (CBR); progression-free survival (PFS); overall survival (OS); safety.

RESULTS

Sixteen eligible patients were enrolled; 10 (62.5%) had endocervical adenocarcinoma. The most common HER2 mutation was S310F (63% of patients). Three of 12 RECIST-measurable patients had confirmed partial responses (ORR 25%; 95%CI 5.5-57.2%); 3 had stable disease ≥16 weeks (CBR 50%; 95%CI 21.1-78.9%). DOR for responders were 5.6, 5.9, and 12.3 months. Median PFS was 7.0 months (95%CI 0.7-18.3 months); median OS was 16.8 months (95%CI 4.1-NE months). Diarrhea (75%), nausea (44%), and decreased appetite (38%) were the most common adverse events. One patient (6%) reported grade 3 diarrhea. There were no grade 4 events, and no diarrhea-related treatment discontinuations.

CONCLUSIONS

Neratinib monotherapy showed evidence of activity in heavily pretreated patients with HER2-mutant cervical cancer, with no new safety signals. Given the few effective options for cervical cancer after platinum-based therapy failure, neratinib warrants further investigation in this molecularly defined patient population.

TRIAL REGISTRATION NUMBER

NCT01953926 (ClinicalTrials.gov), 2013-002872-42 (EudraCT).

Working together for the family: determination of HER oncogene co-amplifications in breast cancer

HER2 is a well-studied tyrosine kinase (TK) membrane receptor which functions as a therapeutic target in invasive ductal breast carcinomas (IDC). The standard of care for the treatment of HER2-positive breast is the antibody trastuzumab. Despite specific treatment unfortunately, 20% of primary and 70% of metastatic HER2 tumors develop resistance. HER2 belongs to a gene family, with four members (HER1-4) and these members could be involved in resistance to anti-HER2 therapies. In this study we designed a probemix to detect the amplification of the four HER oncogenes in a single reaction. In addition, we developed a protocol based on the combination of MLPA with ddPCR to detect the tumor proportion of co-amplified HERs. On 111 IDC, the HER2 MLPA results were validated by FISH (Adjusted r ² = 0,91, p < 0,0001), CISH (Adjusted r ² = 0,938, p < 0,0001) and IHC (Adjusted r ² = 0,31, p < 0,0001). HER1-4 MLPA results were validated by RT-qPCR assays (Spearman Rank test p < 0,05). Of the 111 samples, 26% presented at least one HER amplified, of which 23% showed co-amplifications with other HERs. The percentage of cells with HER2 co-amplified varied among the tumors (from 2-72,6%). Independent in-silico findings show that the outcome of HER2+ patients is conditioned by the status of HER3 and HER4. Our results encourage further studies to investigate the relationship with patient's response to single or combined treatment. The approach could serve as proof of principle for other tumors in which the HER oncogenes are involved.

HER family in cancer progression: From discovery to 2020 and beyond

The human epidermal growth factor receptor (HER) family of receptor tyrosine kinases (RTKs) are among the first layer of molecules that receive, interpret, and transduce signals leading to distinct cancer cell phenotypes. Since the discovery of the tooth-lid factor-later characterized as the epidermal growth factor (EGF)-and its high-affinity binding EGF receptor, HER kinases have emerged as one of the commonly upregulated or hyperactivated or mutated kinases in epithelial tumors, thus allowing HER1-3 family members to regulate several hallmarks of cancer development and progression. Each member of the HER family exhibits shared and unique structural features to engage multiple receptor activation modes, leading to a range of overlapping and distinct phenotypes. EGFR, the founding HER family member, provided the roadmap for the development of the cell surface RTK-directed targeted cancer therapy by serving as a prototype/precursor for the currently used HER-directed cancer drugs. We herein provide a brief account of the discoveries, defining moments, and historical context of the HER family and guidepost advances in basic, translational, and clinical research that solidified a prominent position of the HER family in cancer research and treatment. We also discuss the significance of HER3 pseudokinase in cancer biology; its unique structural features that drive transregulation among HER1-3, leading to a superior proximal signaling response; and potential role of HER3 as a shared effector of acquired therapeutic resistance against diverse oncology drugs. Finally, we also narrate some of the current drawbacks of HER-directed therapies and provide insights into postulated advances in HER biology with extensive implications of these therapies in cancer research and treatment.

Curcumin Enhances the Antitumoral Effect Induced by the Recombinant Vaccinia Neu Vaccine (rV-neuT) in Mice with Transplanted Salivary Gland Carcinoma Cells

The survival rate for head and neck cancer patients has not substantially changed in the last two decades. We previously showed that two rV-neuT intratumoral injections induced an efficient antitumor response and rejection of transplanted Neu (rat ErbB2/neu oncogene-encoded protein)-overexpressing salivary gland tumor cells in BALB-neuT mice (BALB/c mice transgenic for the rat ErbB2/neu oncogene). However, reiterated poxviral vaccinations increase neutralizing antibodies to viral proteins in humans that prevent immune response against the recombinant antigen expressed by the virus. Curcumin (CUR) is a polyphenol with antineoplastic and immunomodulatory properties. The aim of this study was to employ CUR administration to boost the anti-Neu immune response and anticancer activity induced by one rV-neuT intratumoral vaccination in BALB-neuT mice. Here, we demonstrated that the combined rV-neuT+CUR treatment was more effective at reducing tumor growth and increasing mouse survival, anti-Neu humoral response, and IFN-γ/IL-2 T-cell release in vitro than the individual treatment. rV-neuT+CUR-treated mice showed an increased infiltration of CD4⁺/CD8⁺ T lymphocytes within the tumor as compared to those that received the individual treatment. Overall, CUR enhanced the antitumoral effect and immune response to Neu induced by the rV-neuT vaccine in mice. Thus, the combined treatment might represent a successful strategy to target ErbB2/Neu-overexpressing tumors.

The Role of Hormones and Trophic Factors as Components of Preservation Solutions in Protection of Renal Function before Transplantation: A Review of the Literature

Transplantation is currently a routine method for treating end-stage organ failure. In recent years, there has been some progress in the development of an optimal composition of organ preservation solutions, improving the vital functions of the organ and allowing to extend its storage period until implantation into the recipient. Optimizations are mostly based on commercial solutions, routinely used to store grafts intended for transplantation. The paper reviews hormones with a potential nephroprotective effect, which were used to modify the composition of renal perfusion and preservation solutions. Their effectiveness as ingredients of preservation solutions was analysed based on a literature review. Hormones and trophic factors are innovative preservation solution supplements. They have a pleiotropic effect and affect normal renal function. The expression of receptors for melatonin, prolactin, thyrotropin, corticotropin, prostaglandin E1 and trophic factors was confirmed in the kidneys, which suggests that they are a promising therapeutic target for renal IR (ischemia-reperfusion) injury. They can have anti-inflammatory, antioxidant and anti-apoptotic effects, limiting IR injury.

Human epidermal growth factor receptor 2 (Her2) testing for uterine serous carcinoma: Report of scenarios of unusual overexpression

The human epidermal growth factor receptor 2 (Her2) is tested in many human cancers, including breast, bladder, pancreatic, ovarian and stomach. The American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) have issued Clinical Practice Guidelines for reporting Her2 results for breast carcinomas (Wolf et al., 2018). For the last 1-2 years Her2/neu is tested in endometrial serous carcinoma, especially in recurrent tumors or non-responsive tumors as an option for additional treatment. College of American Pathologists (CAP) offers a template for prognostic marker reporting results for specimens with endometrial carcinomas (Fitzgibbons et al., 2019). Her2/neu testing by immunohistochemistry (IHC) mandates rigorous fixation time control, e.g., fixation time should fall within 6-72 h (Recommendations for Her2 Testing in Breast Cancer, 2013). For that reason, in breast cancers, Her2/neu testing is done on initial core biopsy specimens. The test is however, repeated on excision specimen in high grade tumors where Her2/neu expression was initially negative on core biopsies. For endometrial serous carcinoma no guidelines have been set or proposed as of yet. The Gynecologic Oncologists request this test because of proven benefit of adding Trastuzumab (Fader et al., 2018) and that is why it is important to documenting the findings in this report in the literature so that an informed request can be made by the treating oncologist when multiple tissue samples from the same patient are available for testing. Similarly pathologists also can decide which would be the best sample to test when no instruction is received. We report here three separate scenarios of uterine serous carcinomas in which the Her2/neu expressions were unique enough to justify documentation and therefore have implications for determining which specimen is ideal for the Her2 overexpression testing and likely to have highest possibility in identifying the Her2/neu overexpressed clone in the tumor which would expand the therapeutic options for the patients.

Ado-trastuzumab emtansine (T-DM1) in patients with HER2-amplified tumors excluding breast and gastric/gastroesophageal junction (GEJ) adenocarcinomas: results from the NCI-MATCH trial (EAY131) subprotocol Q

BACKGROUND

The National Cancer Institute-Molecular Analysis for Therapy Choice (NCI-MATCH) is a national precision medicine study incorporating centralized genomic testing to direct refractory cancer patients to molecularly targeted treatment subprotocols. This treatment subprotocol was designed to screen for potential signals of efficacy of ado-trastuzumab emtansine (T-DM1) in HER2-amplified histologies other than breast and gastroesophageal tumors.

METHODS

Eligible patients had HER2 amplification at a copy number (CN) >7 based on targeted next-generation sequencing (NGS) with a custom Oncomine AmpliSeq™ (ThermoFisher Scientific) panel. Patients with prior trastuzumab, pertuzumab or T-DM1 treatment were excluded. Patients received T-DM1 at 3.6 mg/kg i.v. every 3 weeks until toxicity or disease progression. Tumor assessments occurred every three cycles. The primary end point was centrally assessed objective response rate (ORR). Exploratory end points included correlating response with HER2 CN by NGS. The impact of co-occurring genomic alterations and PTEN loss by immunohistochemistry were also assessed.

RESULTS

Thirty-eight patients were enrolled and 36 included in efficacy analysis. Median prior therapies in the metastatic setting was 3 (range 0-9; unknown in one patient). Median HER2 CN was 17 (range 7-139). Partial responses were observed in two (5.6%) patients: one mucoepidermoid carcinoma of parotid gland and one parotid gland squamous cell cancer. Seventeen patients (47%) had stable disease including 8/10 (80%) with ovarian and uterine carcinomas, with median duration of 4.6 months. The 6-month progression-free survival rate was 23.6% [90% confidence interval 14.2% to 39.2%]. Common toxicities included fatigue, anemia, fever and thrombocytopenia with no new safety signals. There was a trend for tumor shrinkage with higher levels of gene CN as determined by the NGS assay.

CONCLUSION

T-DM1 was well tolerated. While this subprotocol did not meet the primary end point for ORR in this heavily pre-treated diverse patient population, clinical activity was seen in salivary gland tumors warranting further study in this tumor type in dedicated trials.

Targeting ERBB2 (HER2) Amplification Identified by Next-Generation Sequencing in Patients With Advanced or Metastatic Solid Tumors Beyond Conventional Indications

PURPOSE

Human epidermal growth factor receptor 2 (HER2) is an effective therapeutic target in breast and gastric and gastroesophageal junction cancers. However, less is known about the prevalence of ERBB2 (HER2) amplification and the efficacy of HER2-targeted treatment in other tumors.

PATIENTS AND METHODS

We assessed HER2 amplification status among 5,002 patients with advanced disease (excluding breast cancer) who underwent next-generation sequencing. We evaluated the clinical benefit of HER2-targeted therapy by measuring the time-dependent overall survival (OS) from the genomic testing results, progression-free survival (PFS), and PFS during HER2-targeted therapy (PFS2) compared with PFS during prior therapy (PFS1).

RESULTS

Overall, 122 patients (2.4%) had HER2 amplification, including patients with endometrial (5.3%), bladder (5.2%), biliary or gallbladder (4.9%), salivary (4.7%), and colorectal cancer (3.6%). Forty patients (38%) with nongastric, nongastroesophageal junction, or nonesophageal cancers received at least one line of HER2-targeted therapy. Patients receiving HER2-targeted therapy had a median OS of 18.6 months, compared with 10.9 months for patients who did not receive HER2-targeted therapy (P = .070). On multivariable analysis, HER2-targeted therapy was significantly associated with increased OS (hazard ratio, 0.5; 95% CI, 0.27 to 0.93; P = .029), regardless of sex, age, or number of prior lines of treatment. The PFS2-to-PFS1 ratio was 1.3 or greater in 21 (57%) of 37 patients who received HER2-targeted therapy not in the first line of systemic treatment, and the median PFS2 and PFS1 times were 24 and 13 weeks, respectively (P < .001).

CONCLUSION

HER2 amplifications using next-generation sequencing can be identified in a variety of tumor types. HER2-targeted therapy may confer clinical benefit in tumor types other than those for which HER2 inhibitors are approved.