EGFR-targeted Drugs Research Articles

Single molecule tracking based drug screening

The single-molecule tracking of transmembrane receptors in living cells has provided significant insights into signaling mechanisms, such as mobility and clustering upon their activation/inactivation, making it a potential screening method for drug discovery. Here we show that single-molecule tracking-based screening can be used to explore compounds both detectable and undetectable by conventional methods for disease-related receptors. Using an automated system for a fast large-scale single-molecule analysis, we screen for epidermal growth factor receptor (EGFR) from 1134 of FDA approved drugs. The 18 hit compounds include all EGFR-targeted tyrosine kinase inhibitors (TKIs) in the library that suppress any phosphorylation-dependent mobility shift of EGFR, proving the concept of this approach. The remaining hit compounds are not reported as EGFR-targeted drugs and do not inhibit EGF-induced EGFR phosphorylation. These non-TKI compounds affect the mobility and/or clustering of EGFR without EGF and induce EGFR internalization, to impede EGFR-dependent cell growth. Thus, single-molecule tracking provides an alternative modality for discovering therapeutics on various receptor functions with previously untargeted mechanisms.

Recurrent pancreatic cancer treated with N-803 and PD-L1 t-haNK followed by an EGFR-targeted nanocell drug conjugate.

Multimodal temporal therapy orchestrated to leverage immunotherapy, tumor-targeted chemotherapy, and natural killer (NK) cell therapy may provide an opportunity to induce immunogenic cell death for tumor response and increased survival in patients with recurrent cancer. The interleukin-15 (IL-15) superagonist N-803, an enhancer of NK cells, CD4 + T cells, cytotoxic CD8 + T cells, and memory T-cell activity, combined with off-the-shelf PD-L1-targeted high-affinity NK (PD-L1 t-haNK) cells represent novel immunotherapies designed to overcome an immunosuppressive tumor microenvironment (TME). The epidermal growth factor receptor-targeted antibody-nanocell conjugate E-EDV-D682 provides tumor-targeted chemotherapy in the form of its anthracycline metabolite PNU159682 (nemorubicin) cargo and is currently being studied in combination with immunomodulatory EDVs delivering the adjuvant α-galactosyl ceramide (GC). Here, we report the compassionate use treatment of this combination in a patient with recurrent, metastatic pancreatic cancer (mPC) after 3 lines of therapy. Under the initial single-patient Investigational New Drug (spIND) protocol, the patient received N-803, PD-L1 t-haNK cells, and the albumin doxorubicin conjugate aldoxorubicin for ~27 months. The patient's disease became stable on this regimen, and a transient complete response was observed by ~14 months of therapy. Due to progression, a second spIND protocol was designed whereby the patient received E-EDV-D682 plus EDV-GC for more than 24 months, which resulted in stable disease and the patient's continued survival at the time this report was written. The patient's extended survival despite the dire prognosis associated with recurrent mPC points to the merits of this temporal combination regimen in overcoming immuno-chemo resistance with enhanced immune activity required for tumor response and extended survival.

Griffithazanone A, a sensitizer of EGFR-targeted drug in Goniothalamus yunnanensis for non-small cell lung cancer

Non-small cell lung cancer (NSCLC), which accounts for up to 85 % of lung cancer cases, significantly impacts the health of individuals worldwide. While targeted therapy has played a crucial role, the emergence of EGFR resistance and adverse reactions has made it imperative to explore new medications. Natural products derived from plants became an important source of anti-tumor drugs. In this study, nine known compounds, including seven alkaloids (1–7) and two styryllactones (8 and 9) were isolated from twigs and leaves of Goniothalamus yunnanensis. Their structures were elucidated by their NMR spectroscopic data. Among them, griffithazanone A (1) showed the strongest inhibitory activity with the IC50 value of 6.775 μM. Our findings revealed that griffithazanone A treatment induced cytotoxicity, apoptosis, and ROS generation in A549 cells in a dose-dependent manner. It regulates the expression of apoptosis-related proteins Bax, Bcl-2, and cleaved-caspase3 both in vitro and in vivo. Further investigation demonstrated that griffithazanone A regulated the proteins involved in the ASK1/JNK/p38 and BAD/Bcl-2 pathways in A549 cells by targeting PIM1. Moreover, griffithazanone A treatment enhanced the efficacy of gefitinib and osimertinib and reversed osimertinib resistance. Overall, our study highlights the potential of griffithazanone A in inhibiting the progression of NSCLC by targeting PIM1 and reversing resistance to EGFR targeted drugs.

Hypomagnesemia as a predictor of the efficacy of combination EGFR-targeted drugs versus EGFR ADCs alone in HNSCC.

146 Background: EGFR-targeted drugs and ADCs in combination with EGFR-conjugated chemotherapy drugs can both cause hypomagnesemia. However, the predictive value of hypomagnesemia in response to treatment for head and neck squamous cell carcinoma (HNSCC) is unclear. Methods: This study retrospectively analyzed patients who participated in clinical trials of EGFR-targeted drugs and EGFR ADCs for HNSCC and solid tumors, from February 24, 2022, to March 25, 2024. The primary endpoint of the study was time to treatment failure (TTF). Results: This study conducted a retrospective analysis of 68 patients . All patients exhibited normal baseline serum magnesium levels prior to treatment, but following two cycles of treatment, varying degrees of hypomagnesemia were observed among them. Among the 46 patients who received 2 cycles of combination therapy with EGFR-targeted drugs, 33 were hypomagnesemia and 13 were normal serum magnesium, ORR[90.9%vs. 8.5%,(P=0.002)] (Table), TTF [151 days (95% CI: 212-380) vs. 87 days (95% CI: 52-230), HR 0.576 (95% CI: 0.270–1.230,P = 0.021)]. Among the 22 patients who received EGFR ADC alone for 2 cycles, 8 were hypomagnesemia and 14 were normal serum magnesium, ORR [37.5% vs.28.6%, (P=0.549)] (Table), TTF [97.5 days (95% CI: 68-300) vs. 108.5 days (95% CI: 60-160), HR of 0.877 (95% CI: 0.339–2.263; P = 0.547)]. Conclusions: The study demonstrates that, the occurrence of hypomagnesemia is associated with ORR and TTF following two cycles of combination of EFGR-targeted drugs, not observed in patients receiving EGFR ADCs as monotherapy in HNSCC. [Table: see text]

Targeting Epidermal Growth Factor Receptor with Ficus virens Metabolites to Manage Cancer Progression: Molecular Docking and ADME Study

Introduction: Targeting epidermal growth factor receptor (EGFR) has been used in the treatment of several cancer types where EGFR has a notable involvement in signalling pathways. Medicinal plants are the oldest and healthiest source of medication used in modern pharmacological therapy. Previous research indicates that the compounds found in Ficus virens stem bark have significant therapeutic properties against a range of illnesses, including cancer. Therefore, in this study, molecular docking research was conducted to determine the binding interactions and affinity of secondary metabolites predicted in F. virens methanolic extract with the target protein, EGFR. Materials and Methods: Three-dimensional (3D) conformers of the secondary metabolism products and adenosine triphosphate (ATP) were collected from PubChem on 5 January 2024. The 3D structure of EGFR and its inhibitor was retrieved from the Protein Data Bank (PDB) databank and ligands and proteins were converted to AutoDock-compatible format and then the energy minimisation was performed by the Open Babel in PyRx. Finally, using PyRx-Python 0.8, molecular docking was done, and using Discovery Studio, visualisation was done as well. The grid box dimensions were specified at 30 Å ×30 Å ×25 Å, and the physiochemical property evaluation was done by the SwissADME online server. Results: In this study, molecular docking assessed 14 compounds, including phytochemicals and ATP, for their binding with EGFR (PDB Id: 1XKK). Redocking of lapatinib validated the results. Natural chemicals showed binding energies from −4.0 to −7.8 Kcal/mol, with oleic acid and iso-caryophyllene demonstrating promising interactions, sourced from F. virens. Despite some limitations, these compounds exhibit potential for EGFR-targeted drug development, despite one Lipinski’s rule violation. Conclusions: EGFR inhibitory activities of iso-caryophyllene and oleic acid, which were identified in the F. virens methanol extract, were remarkable and higher than that of the substrate; their potential opens up exciting new possibilities for moving forward with cancer treatment. It is encouraged to further investigate the in vivo effectiveness of iso-caryophyllene, by means of animal models and cell lines.

PDZK1 suppresses TNBC development and sensitizes TNBC cells to erlotinib via the EGFR pathway

Epidermal growth factor receptor (EGFR)-targeted drugs (erlotinib, etc.) are used to treat multiple types of tumours. EGFR is highly expressed in most triple-negative breast cancer (TNBC) patients. However, only a small proportion of TNBC patients benefit from EGFR-targeted drugs in clinical trials, and the resistance mechanism is unclear. Here, we found that PDZ domain containing 1 (PDZK1) is downregulated in erlotinib-resistant TNBC cells, suggesting that PDZK1 downregulation is related to erlotinib resistance in TNBC. PDZK1 binds to EGFR. Through this interaction, PDZK1 promotes EGFR degradation by enhancing the binding of EGFR to c-Cbl and inhibits EGFR phosphorylation by hindering EGFR dimerisation. We also found that PDZK1 is specifically downregulated in TNBC tissues and correlated with a poor prognosis in TNBC patients. In vitro and in vivo functional assays showed that PDZK1 suppressed TNBC development. Restoration of EGFR expression or kinase inhibitor treatment reversed the degree of cell malignancy induced by PDZK1 overexpression or knockdown, respectively. PDZK1 overexpression sensitised TNBC cells to erlotinib both in vitro and in vivo. In conclusion, PDZK1 is a significant prognostic factor for TNBC and a potential molecular therapeutic target for reversing erlotinib resistance in TNBC cells.

Abstract 684: DT-9045, a novel PAR2 inhibitor with best-in-class properties that reduces resistance to both EGFR-targeting therapies and immunotherapy in oncology models

Abstract Protease-activated receptor 2 (PAR2) is a promising therapeutic target in oncology and immuno-oncology. It is upregulated and associated with poor prognosis in several cancer types. A pan-cancer meta-analysis showed that PAR2 is one of the genes most significantly associated with resistance to immune checkpoint blockade (ICB) and T cells dysfunction in cancer patients. Mechanistically, being expressed by various cells of the tumor microenvironment, PAR2 promotes both survival and proliferation of cancer cells and dampens the anti-cancer immune response. Domain Therapeutics has developed a novel PAR2 inhibitor, DT-9045, with best-in-class properties. Indeed, compared to its most advanced competitors, DT-9045 is a small molecule, orally bioavailable, insurmountable, biased, and active in tumor-like conditions (i.e. acidic pH and high level of activating proteases). This compound is also highly potent and selective on PAR2. Pharmacokinetic properties are suitable with a once-a-day oral administration. In vitro, DT-9045 completely prevented PAR2-mediated resistance to EGFR-targeting drugs. In vivo, its combination with anti-PD1 therapy showed a significant increase in efficacy over monotherapies in preclinical syngeneic mouse cancer models. This result was similar to the one observed in PAR2 knockout mice, indicating that oral administration of DT-9045 induces a complete inhibition of the receptor. We have further demonstrated that treatment with a PAR2 inhibitor enhances dendritic cell-mediated T cell activation and intratumoral infiltration of CD4+ and CD8+ T cells as well as a decrease in M2 macrophage infiltration. In conclusion, Domain Therapeutic has identified a novel PAR2 inhibitor, DT-9045, with clear competitive advantages. This preclinical candidate has shown strong potency in alleviating the resistance to both EGFR-targeting therapies and immunotherapy in preclinical cancer models. IND-enabling studies are currently ongoing to bring this new hope for cancer patients to the clinic. Citation Format: Thibaut Brugat, Maleck Kadiri, Samya Aouad, Anne-Laure Blayo, Baptiste Rugeri, Antoine Mousson, Aurélie Janvier, Edith Steinberg, Luc Baron, Mandy Recolet, Xavier Wirth, Maria Jesus Garcia-Leon, Quentin Ruet, Meriem Semache, Laurent Sabbagh, Orphée Blanchard, Christel Franchet, Stanislas Mayer, John Stagg, Nathalie Lenne, Stephan Schann. DT-9045, a novel PAR2 inhibitor with best-in-class properties that reduces resistance to both EGFR-targeting therapies and immunotherapy in oncology models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 684.

Abstract 549: PDZK1 sensitizes TNBC cells to erlotinib via promoting c-Cbl-mediated EGFR degradation and inhibiting EGFR phosphorylation

Abstract Background: Triple-negative breast cancer (TNBC) is lack of effective targeted therapies. Epidermal growth factor receptor (EGFR) is a potential therapeutic target for TNBC. However, TNBC is resistant to EGFR-targeted drugs in clinical trials, and the tolerance mechanism remains unclear. This study aimed to elucidate the possible resistance mechanism for TNBC to EGFR-targeted therapy and how sensitize TNBC cells to erlotinib. Methods: PDZ domain containing 1 (PDZK1) correlated with TNBC development was screened out by bioinformatics analysis and its correlation with resistance to erlotinib was identified by western blotting (WB). Its interaction with EGFR and structural basis were determined by GST-Pull down and coimmunoprecipitation. Its regulation on EGFR signaling activation and expression level were detected by WB in PDZK1 overexpression and knockdown TNBC cells, xenograft tissues and correlation analyses. Correlation was performed by gene set enrichment analysis (GSEA) and immunohistochemistry of tissue microarray followed by Pearson analysis. TNBC-suppressing effects of PDZK1 and its sensitizing effects on erlotinib were investigated using cell viability assay, colony-forming assay, wound healing assay, Matrigel invasion assay and xenograft model in combination with PDZK1 wild type/mutant transfection and rescue experiment. Results: Here we found that PDZK1 was correlated with TNBC development and its level was downregulated in erlotinib-resistant TNBC cells, suggesting that PDZK1 downregulation was related to erlotinib resistance in TNBC. PDZK1 bound with EGFR. Through the interaction, PDZK1 promoted EGFR degradation by enhancing the binding of EGFR with c-Cbl and inhibited EGFR phosphorylation by hindering EGFR dimerization. PDZK1 was specifically downregulated in TNBC tissues and was correlated with poor prognosis of TNBC. Functional assays in vitro and in vivo showed that PDZK1 suppressed TNBC development. Restoring EGFR expression and kinase inhibitor treatment reversed the malignancy caused by PDZK1 overexpression and knockdown, respectively. PDZK1 wild type, but not mutant overexpression enhanced the inhibitory effect of erlotinib on EGFR signaling and TNBC malignancy in vitro and in vivo. Conclusion: PDZK1 is a significant prognostic factor for TNBC and a potential molecular therapeutic target for TNBC to reverse the tolerance of TNBC cells to erlotinib. Citation Format: Junfang Zheng, Yuanzhen Ma, Zhiyu Fang, Yijun Qi. PDZK1 sensitizes TNBC cells to erlotinib via promoting c-Cbl-mediated EGFR degradation and inhibiting EGFR phosphorylation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 549.

Targeted Inhibitors of EGFR: Structure, Biology, Biomarkers, and Clinical Applications.

Members of the EGFR family of tyrosine kinase receptors are major regulators of cellular proliferation, differentiation, and survival. In humans, abnormal activation of EGFR is associated with the development and progression of many cancer types, which makes it an attractive target for molecular-guided therapy. Two classes of EGFR-targeted cancer therapeutics include monoclonal antibodies (mAbs), which bind to the extracellular domain of EGFR, and tyrosine kinase inhibitors (TKIs), which mostly target the intracellular part of EGFR and inhibit its activity in molecular signaling. While EGFR-specific mAbs and three generations of TKIs have demonstrated clinical efficacy in various settings, molecular evolution of tumors leads to apparent and sometimes inevitable resistance to current therapeutics, which highlights the need for deeper research in this field. Here, we tried to provide a comprehensive and systematic overview of the rationale, molecular mechanisms, and clinical significance of the current EGFR-targeting drugs, highlighting potential candidate molecules in development. We summarized the underlying mechanisms of resistance and available personalized predictive approaches that may lead to improved efficacy of EGFR-targeted therapies. We also discuss recent developments and the use of specific therapeutic strategies, such as multi-targeting agents and combination therapies, for overcoming cancer resistance to EGFR-specific drugs.

Exploring the conformational dynamics and thermodynamics of EGFR S768I and G719X + S768I mutations in non-small cell lung cancer: An in silico approaches.

Non-small cell lung cancer (NSCLC) is often driven by mutations in the epidermal growth factor receptor (EGFR) gene. However, rare mutations such as G719X and S768I lack standard anti-EGFR targeted therapies. Understanding the structural differences between wild-type EGFR and these rare mutants is crucial for developing EGFR-targeted drugs. We performed a systematic analysis using molecular dynamics simulations, essential dynamics (ED), molecular mechanics Poisson-Boltzmann surface area, and free energy calculation methods to compare the kinetic properties, molecular motion, and free energy distribution between wild-type EGFR and the rare mutants' structures G719X-EGFR, S768I-EGFR, and G719X + S768I-EGFR. Our results showed that S768I-EGFR and G719X + S768I-EGFR have higher global and local conformational flexibility and lower thermal and global structural stability than WT-EGFR. ED analysis revealed different molecular motion patterns between S768I-EGFR, G719X + S768I-EGFR, and WT-EGFR. The A-loop and αC-helix, crucial structural elements related to the active state, showed a tendency toward active state development, providing a molecular mechanism explanation for NSCLC caused by EGFR S768I and EGFR G719C + S768I mutations. The present study may be helpful in the development of new EGFR-targeted drugs based on the structure of rare mutations. Our findings may aid in developing new targeted treatments for patients with EGFR S768I and EGFR G719X + S768I mutations.

Understanding and Targeting the Epigenetic Regulation to Overcome EGFR-TKIs Resistance in Human Cancer.

The occurrence and progression of cancer are the results of the dysregulation of genetics and epigenetics. Epigenetic regulation can reversibly affect gene transcription activity without changing DNA structure. Covalent modification of histones is crucial in the epigenetic regulation of gene expression. Furthermore, epidermal growth factor receptor (EGFR) significantly affects cell tumorigenesis, proliferation, antitumor drug resistance, etc. Overexpression of EGFR promotes cancer development. Therefore, EGFR-targeted drugs have become the focus of tumor therapy. With the advent of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), EGFR-TKIs resistance, which occurs about half a year to a year, has become an obstacle in cancer treatment. The objective of this study is to discuss the ways to overcome EGFR-TKIs resistance in a variety of tumors. The combination therapy of epigenetic drugs and other drugs is used. The combination of the two drugs can overcome the resistance of EGFR-TKIs and prolong the survival of patients. This article depicts the concepts of epigenetics and the mechanism of EGFR-TKIs resistance and then illustrates the relationship between epigenetic mechanisms and EGFR-TKIs resistance. Finally, it discusses the clinical research and the latest patents for using epigenetic drugs to reverse EGFR-TKIs resistance in human cancer. In the future, more novel targets may be discovered for overcoming resistance to EGFR-TKIs, not just on histone deacetylases (HDACs). The dosing course and mode of administration of the combination therapy containing epigenetic drugs need further study. This review provides new ideas for using epigenetic agents to overcome EGFR-TKIs resistance.

Inhibition of a lower potency target drives the anticancer activity of a clinical p38 inhibitor

The small-molecule drug ralimetinib was developed as an inhibitor of the p38α mitogen-activated protein kinase, and it has advanced to phase 2 clinical trials in oncology. Here, we demonstrate that ralimetinib resembles EGFR-targeting drugs in pharmacogenomic profiling experiments and that ralimetinib inhibits EGFR kinase activity invitro and in cellulo. While ralimetinib sensitivity is unaffected by deletion of the genes encoding p38α and p38β, its effects are blocked by expression of the EGFR-T790M gatekeeper mutation. Finally, we solved the cocrystal structure of ralimetinib bound to EGFR, providing further evidence thatthis drug functions as an ATP-competitive EGFR inhibitor. We conclude that, though ralimetinib is>30-fold less potent against EGFR compared to p38α, its ability to inhibit EGFR drives its primary anticancer effects. Our results call into question the value of p38α as an anticancer target, and we describe a multi-modal approach that can be used to uncover a drug's mechanism-of-action.

Unraveling the signaling mechanism behind astrocytoma and possible therapeutics strategies: A comprehensive review.

A form of cancer called astrocytoma can develop in the brain or spinal cord and sometimes causes death. A detailed overview of the precise signaling cascade underlying astrocytoma formation has not yet been revealed, although various factors have been investigated. Therefore, our objective was to unravel and summarize our current understanding of molecular genetics and associated signaling pathways with some possible therapeutic strategies for astrocytoma. In general, four different forms of astrocytoma have been identified in individuals, including circumscribed, diffuse, anaplastic, and multiforme glioblastoma, according to a recent literature review. All types of astrocytoma have a direct connection with some oncogenic signaling cascade. Common signaling is MAPK cascade, including Ras-Raf-ERK, up-regulated with activating EGFR/AKT/PTEN/mTOR and PDGFR. Recent breakthrough studies found that BRAF mutations, including KIAA1549: BRAF and BRAF V600E are responsible for astrocytoma progression. Additionally, cancer progression is influenced by mutations in some tumor suppressor genes, such as the Tp53/ATRX and MGMT mutant. As synthetic medications must cross the blood-brain barrier (BBB), modulating signal systems such as miRNA is the primary option for treating patients with astrocytoma. However, available surgery, radiation therapy, and experimental therapies such as adjuvant therapy, anti-angiogenic therapy, and EGFR-targeting antibody drug are the usual treatment for most types of astrocytoma. Similar to conventional anticancer medications, some phytochemicals slow tumor growth by simultaneously controlling several cellular proteins, including those involved in cell cycle regulation, apoptosis, metastatic spread, tyrosine kinase, growth factor receptor, and antioxidant-related proteins. In conclusion, cellular and molecular signaling is directly associated with the development of astrocytoma, and a combination of conventional and alternative therapies can improve the malignancy of cancer patients.

Downregulation of AP1S1 causes the lysosomal degradation of EGFR in non-small cell lung cancer.

Matrix stiffness has been shown to play a critical role in cancer progression by influencing various cellular processes, including epidermal growth factor (EGF) signaling. However, the underlying molecular mechanisms are not fully understood. Here, we investigated the role of adaptor-related protein complex 1 subunit sigma 1 (AP1S1), a component of adaptor protein complex-1, in the regulation of EGF receptor (EGFR) intracellular trafficking during cancer cell progression. We found that AP1S1 expression was upregulated under stiff matrix conditions, resulting in the regulation of EGFR trafficking in non-small cell lung adenocarcinoma cells. Knockout of AP1S1 caused the lysosomal degradation of EGFR, leading to suppressed EGF-induced anaplastic lymphoma receptor tyrosine kinase phosphorylation. In addition, the downregulation of AP1S1 increased the sensitivity of H1975 cancer cells, which are resistant to tyrosine kinase inhibitors, to erlotinib. Collectively, our results suggest that AP1S1 could regulate EGFR recycling under stiff matrix conditions, and AP1S1 inhibition could be a novel strategy for treating cancer cells resistant to EGFR-targeted anticancer drugs.

AXL activates YAP through the EGFR-LATS1/2 axis and confers resistance to EGFR-targeted drugs in head and neck squamous cell carcinoma.

The Hippo signaling pathway and its downstream effector YAP play a central role in cell proliferation. Dysregulation of the Hippo pathway triggers YAP hyperactivation, thereby inducing head and neck squamous cell carcinoma (HNSCC). Recently, we reported that EGFR promotes tyrosine phosphorylation of MOB1 and subsequent LATS1/2 inactivation, which are core components of the Hippo pathway, resulting in YAP activation. However, EGFR-targeted monotherapy has shown a low response rate in HNSCC patients. Given that YAP is activated in patient samples refractory to EGFR-targeted therapy, EGFR inhibitors may temporarily inactivate YAP, but intrinsic hyperactivation or acquired reactivation of YAP may confer resistance to EGFR inhibitors in HNSCC cells. The mechanism by which YAP is activated in HNSCC resistant to EGFR inhibitors remains unclear. Comprehensive transcriptional analysis revealed that AXL activates YAP through a novel mechanism: AXL heterodimerizes with EGFR, thereby activating YAP via the EGFR-LATS1/2 axis. The combination of AXL and EGFR inhibitors synergistically inactivates YAP and suppresses the viability of HNSCC and lung adenocarcinoma cells. In turn, LATS1/2 knockout and YAP hyperactivation confer resistance to the synergistic effects of these inhibitors. Our findings suggest that co-targeting both AXL and EGFR represent a promising therapeutic approach in patients with EGFR-altered cancers.

Abstract 2094: A user-friendly R Shiny app for predicting drug response of cancer using deep learning

Abstract Realizing the full potential of precision oncology requires accurate prediction of treatment response. We previously developed a deep learning model, namely DeepDR, to predict drug sensitivity by integrating baseline profiles of mutations and gene expression of a cancer sample (Chiu et al.; DOI: 10.1186/s12920-018-0460-9). The model features a transfer learning design that captures two types of features: i) tumor relevant representations of mutation and expression data learned from tumor samples, and ii) predictive model for drug response (measured by IC50 values) learned from high-throughput drug screens of pan-cancer cell lines. DeepDR was applicable to both cell lines and tumors and achieved superior performance over conventional methods. To make the DeepDR model more accessible to biomedical researchers with limited programming skills, here we present a user-friendly platform implemented by using an R Shiny framework. The R Shiny app is a web interface that allows users to upload mutation and/or gene expression profiles of a cancer sample (cell or tumor model) and predict the sample’s response to 265 FDA-approved and investigational compounds covered by the screening library of the Genomics of Drug Sensitivity in Cancer (GDSC) project. The app provides an intuitive user interface to interactively visualize, search, and filter prediction results among 265 compounds. It also enables downstream analyses including statistical tests and provides links to external compound databases, such as PubChem. In the original publication of DeepDR, we have validated its performance across cell lines and tumors using well-known pharmacogenomic associations, such as estrogen receptor antagonist (tamoxifen) and EGFR-targeting drugs (afatinib and gefitinib), as well as a novel agent, CX-5461, in treating hematopoietic malignancies. Here we utilized the proposed Shiny app to further predict drug sensitivity of patients with hepatocellular carcinoma (HCC; n=356) of The Cancer Genome Atlas (TCGA). We investigated CTNNB1 as a demonstrating example for it is one of the most prevalent, yet undruggable, trunk mutations of HCC. A systematic search yielded nine compounds that were predicted to be significantly more effective in HCC tumors harboring CTNNB1 mutations (n=92) compared to others (n=264) (with one-tailed t-test P < 0.0001). These top compounds target critical cancer pathways, such as cell apoptosis (p53 activator and Bcl-2 inhibitor), the PI3K/AKT and MAPK signaling pathways, and DNA-dependent protein kinases, suggesting candidates for further in vitro and in vivo investigations. In summary, the present R Shiny app is a user-friendly platform that enables in silico drug screening using deep learning with no requirement of programming experience. We expect the tool to foster accessibility of our deep learning prediction machine and facilitate the process of drug development in cancer. Citation Format: Li-Ju Wang, Michael Ning, Tapsya Nayak, Satdarshan P. Monga, Yufei Huang, Yidong Chen, Yu-Chiao Chiu. A user-friendly R Shiny app for predicting drug response of cancer using deep learning [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2094.

Glucocorticoid reduces the efficacy of afatinib on the head and neck squamous cell carcinoma

Glucocorticoids (GC) are widely used to counter the adverse events during cancer therapy; nonetheless, previous studies pointed out that GC may reduce the efficacy of chemotherapy on cancer cells, especially in epidermal growth factor receptor (EGFR)-targeted therapy of head and neck squamous cell carcinoma (HNSCC) remaining to be elucidated. The primary aim of the present study was to probe into the GC-induced resistance of EGFR-targeted drug afatinib and the underlying mechanism. HNSCC cell lines (HSC-3, SCC-25, SCC-9, and H-400) and the human oral keratinocyte (HOK) cell lines were assessed for GC receptor (GR) expression. The promoting tumor growth effect of GC was evaluated by the CCK-8 assay and flow cytometry. Levels of signaling pathways participants GR, mTOR, and EGFR were determined by quantitative polymerase chain reaction and western blotting. GC increased the proliferation of HNSCC cells in a GR-dependent manner and promoted AKT/mTOR signaling. But GC failed in counteracting the inhibition of rapamycin in the mTOR signaling pathway. Besides, GC also induced resistance to EGFR-targeted drug afatinib through AKT/mTOR instead of the EGFR/ERK signaling pathway. Thus, GCs reduce the efficacy of afatinib on HNSCC, implicating a cautious use of glucocorticoids in clinical practice.

Antitumor efficacy of a recombinant EGFR-targeted fusion protein conjugate that induces telomere shortening and telomerase downregulation

ObjectiveTo prepare a recombinant EGFR-targeted fusion protein drug conjugate acting on telomere and telomerase; and evaluate its antitumor efficacy. MethodsWe prepared a recombinant fusion protein Fv-LDP-D3 which consists of the Fv fragment of an anti-EGFR monoclonal antibody (MAb), the apoprotein of lidamycin (LDP), and the third domain (D3) of human serum albumin (HSA); then generated the conjugate Fv-LDP-D3∼AE by integrating the active enediyne chomophore (AE) of lidamycin. Accordingly, in vitro and in vivo experiments were performed. ResultsAs shown, Fv-LDP-D3 specifically bound to EGFR highly-expressing cancer cells and intensely entered K-Ras mutant cells via enhanced macropinocytosis. By in vivo imaging, Fv-LDP-D3 displayed intense accumulation and persistent retention in tumor-site. Furthermore, the conjugate Fv-LDP-D3∼AE displayed highly potent cytotoxicity to cancer cells with IC50 at 0.1 nM level. The conjugate induced telomere shortening and downregulation of telomerase and EGFR pathway related proteins. Fv-LDP-D3∼AE exhibited prominent antitumor efficacy against human colorectal cancer xenograft accompanying with significant increase of serum IFN-β in athymic mice. ConclusionThe recombinant fusion protein conjugate that exhibits the capability of tumor-targeting drug delivery can induce telomere shortening and telomerase downregulation. The investigation may lay the foundation for the development of MAb-HSA domain-based fusion protein drug conjugates.

Exploratory Evaluation of EGFR-Targeted Anti-Tumor Drugs for Lung Cancer Based on Lung-on-a-Chip.

In this study, we used three-dimensional (3D) printing to prepare a template of a microfluidic chip from which a polydimethylsiloxane (PDMS)lung chip was successfully constructed. The upper and lower channels of the chip are separated by a microporous membrane. The upper channel is seeded with lung cancer cells, and the lower channel is seeded with vascular endothelial cells and continuously perfused with cell culture medium. This lung chip can simulate the microenvironment of lung tissue and realize the coculture of two kinds of cells at different levels. We used a two-dimensional (2D) well plate and a 3D lung chip to evaluate the effects of different EGFR-targeting drugs (gefitinib, afatinib, and osimertinib) on tumor cells. The 3D lung chip was superior to the 2D well plate at evaluating the effect of drugs on the NCI-H650, and the results were more consistent with existing clinical data. For primary tumor cells, 3D lung chips have more advantages because they simulate conditions that are more similar to the physiological cell microenvironment. The evaluation of EGFR-targeted drugs on lung chips is of great significance for personalized diagnosis and treatment and pharmacodynamic evaluation.

Abstract 334: Convection enhanced delivery of EGFR-targeting antibody drug conjugates ABBV-321 and Depatux-M

Abstract Introduction: EGFR targeted antibody-drug conjugates (ADCs) show promise as a novel treatment in a subset of glioblastoma (GBM). Two EGFR targeting ADCs include first generation Depatux-M, with an antimitotic toxin monomethyl auristatin F (MMAF), and ABBV-321, with a DNA crosslinking agent pyrrolobenzodiazepine dimer (PBD) toxin. Due to the large molecular weight, poor drug distribution across the blood-brain barrier significantly limits the efficacy in EGFR-amplified GBM. We studied whether convection enhanced delivery (CED) can be used to safely infuse these two EGFR-targeted ADCs in patient-derived xenograft (PDX) models of EGFR-amplified GBM. Methods: The efficacy of Depatux-M and ABBV-321 was evaluated in vitro and in vivo in two EGFRviii-amplified PDXs (GBM6 and GBM108). Immunofluorescence staining was used to evaluate drug distribution along with pharmacodynamics of the ADCs. CED was performed by stereotactic placement of an infusion catheter in the same location as the original tumor implantation. Immunohistochemistry was used to explore mechanisms of normal cell toxicity. Results: Despite potent activity in vitro (high ng/ml IC50), systemic administration of either ADC conferred minimal extension in survival for either GBM6 or GBM108. In contrast, CED significantly enhanced ADC delivery to tumor and peri-tumoral regions and extended survival. In a pilot study in GBM6 with n=3 mice per group, a single CED infusion of 0.002mg ABBV-321 resulted in extended survival beyond 365 days for two mice, while other doses and placebo were associated with shorter median survival (0 mg - 39 days; 0.03 mg - 105 days; 0.3 mg - 49 days). In a subsequent trial evaluating serial infusions performed every 21 days, four infusions at 0.002 mg ABBV-321 resulted in lethal toxicity. In contrast, limiting ABBV-321 to only two serial CED infusions in GBM108 was associated with extended survival of more than 300 days vs. 53 days for AB095 antibody control infusion. In contrast, serial infusion with Depatux-M was much better tolerated. In a single infusion in GBM6, a 0.06 mg dose was well tolerated and associated with a 49-day extension in median survival. Further, four serial infusions at 0.06 mg given every 21 days in GBM6 and GBM108 was associated with 100 day and more than 250-day extension in survival as compared to AB095 antibody control infusion. To investigate the mechanism of toxicity, infusion of non-tumor bearing C57Bl6 mice with ABBV-321 resulted in a marked loss in NeuN staining and elevated CD68 and GFAP staining 7 days later; Depatux-M infusion was only associated with modest elevation in GFAP without loss of NeuN staining or elevated CD68-positive cells. Conclusion: Depatux-M is well tolerated when infused into normal brain and results in extended survival in orthotopic GBM PDXs. In contrast, ABBV-321, with a distinct PBD toxin, had a much narrower therapeutic window when delivered by CED. Citation Format: Kendra A. Porath, Ann Mladek, Rachael A. Vaubel, Michael S. Regan, Sonia Jain, Danielle Burgenske, Katrina Bakken, Brett Carlson, Margaret Connors, Zeng Hu, Lihong He, Paul A. Decker, Gaspar Kitange, Shiv Gupta, Nathalie Y. Agar, Thomas M. Feldsien, Didier R. Lefebvre, Jann N. Sarkaria. Convection enhanced delivery of EGFR-targeting antibody drug conjugates ABBV-321 and Depatux-M [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 334.