Fibroblast Growth Factor Receptor Research Articles

Phylogenetic and transcriptomic characterization of insulin and growth factor receptor tyrosine kinases in crustaceans.

Receptor tyrosine kinases (RTKs) mediate the actions of growth factors in metazoans. In decapod crustaceans, RTKs are implicated in various physiological processes, such molting and growth, limb regeneration, reproduction and sexual differentiation, and innate immunity. RTKs are organized into two main types: insulin receptors (InsRs) and growth factor receptors, which include epidermal growth factor receptor (EGFR), fibroblast growth factor receptor (FGFR), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR). The identities of crustacean RTK genes are incomplete. A phylogenetic analysis of the CrusTome transcriptome database, which included all major crustacean taxa, showed that RTK sequences segregated into receptor clades representing InsR (72 sequences), EGFR (228 sequences), FGFR (129 sequences), and PDGFR/VEGFR (PVR; 235 sequences). These four receptor families were distinguished by the domain organization of the extracellular N-terminal region and motif sequences in the protein kinase catalytic domain in the C-terminus or the ligand-binding domain in the N-terminus. EGFR1 formed a single monophyletic group, while the other RTK sequences were divided into subclades, designated InsR1-3, FGFR1-3, and PVR1-2. In decapods, isoforms within the RTK subclades were common. InsRs were characterized by leucine-rich repeat, furin-like cysteine-rich, and fibronectin type 3 domains in the N-terminus. EGFRs had leucine-rich repeat, furin-like cysteine-rich, and growth factor IV domains. N-terminal regions of FGFR1 had one to three immunoglobulin-like domains, whereas FGFR2 had a cadherin tandem repeat domain. PVRs had between two and five immunoglobulin-like domains. A classification nomenclature of the four RTK classes, based on phylogenetic analysis and multiple sequence alignments, is proposed.

Ligand bias underlies differential signaling of multiple FGFs via FGFR1.

The differential signaling of multiple FGF ligands through a single fibroblast growth factor (FGF) receptor (FGFR) plays an important role in embryonic development. Here, we use quantitative biophysical tools to uncover the mechanism behind differences in FGFR1c signaling in response to FGF4, FGF8, and FGF9, a process which is relevant for limb bud outgrowth. We find that FGF8 preferentially induces FRS2 phosphorylation and extracellular matrix loss, while FGF4 and FGF9 preferentially induce FGFR1c phosphorylation and cell growth arrest. Thus, we demonstrate that FGF8 is a biased FGFR1c ligand, as compared to FGF4 and FGF9. Förster resonance energy transfer experiments reveal a correlation between biased signaling and the conformation of the FGFR1c transmembrane domain dimer. Our findings expand the mechanistic understanding of FGF signaling during development and bring the poorly understood concept of receptor tyrosine kinase ligand bias into the spotlight.

439 Extracellular-in-frame deletions and kinase domain duplications are novel, gain-of-function mutations in fibroblast growth factor receptor genes in cancer

OBJECTIVES/GOALS: There are gain-of-function genomic alterations in FGFR genes that guide personalized treatment in some patients with cholangiocarcinoma (10%) and bladder cancer (30%) who can benefit from targeted therapies. We sought to evaluate other genomic alterations in cancer involving FGFRs and assess whether they are gain-of-function. METHODS/STUDY POPULATION: We collaborated with Foundation Medicine Inc (FMI), for the assessment of 300,000 sequenced tumors and a retrospective analysis of recent publications, to identify novel candidate FGFR alterations. We propose to transiently transfect HEK293T cells with an empty vector (EV), FGFR1-4 wild-type (WT), and these variants and use a luminescent-proximity based high-throughput assay, AlphaLISA, and Western blot to assess FGFR and phosphorylated downstream signaling proteins, FRS2, AKT and ERK, and their sensitivity to FGFR inhibitors: pemigatinib, erdafitinib, futibatinib, RLY-4008, and TYRA-200. RESULTS/ANTICIPATED RESULTS: Through our collaboration we identified >100 novel candidate FGFR1-4 variants of unknown significance (VUS) including extracellular-in-frame deletions (EIDs), kinase domain duplications (KDDs), insertions/deletions (INDELs), short number variants (SNVs), and truncations. Immunoblot analysis confirmed the presence of desired EV, FGFR WT, and VUS’ in HEK293T cells. We anticipate the FGFR EIDs and KDDs to display an increased presence of in the respective pFGFR, pFRS2, pERK, and pAKT as compared to the EV and FGFR WT by both immunoblot and AlpahLISA analysis. Additionally, we anticipate the VUS’ to be sensitive to FGFR inhibitors: pemigatinib, erdafitinib, futibatinib, RLY-4008, and TYRA-200 using the AlphaLISA assay. DISCUSSION/SIGNIFICANCE: These findings suggest that the novel FGFR VUS’ are capable of constitutive activation of FGFR kinase activity, and they preliminary demonstrate that these newly identified FGFR alterations are therapeutically targetable. Thus, providing rationale for further clinical evaluation to identify new cohorts of FGFR inhibitor responders.

The Role of Fibroblast Growth Factor-Receptor Pathway Aberrations in Pediatric Diseases

The fibroblast growth factor receptors play a crucial role in binding to fibroblast growth factor and are involved in various pathological conditions. These receptors consist of an extracellular ligand domain, a transmembrane helix domain, and an intracellular domain with tyrosine kinase activity. There are over 48 different isoforms of FGFR. Each FGF receptor in ligand-binding properties and kinase domains. The FGF/FGFR signaling pathway is implicated in various pediatric cancers and therefore are both non-selective and selective FGFR inhibitors available. Additionally, there are five distinct membrane FGF receptors dentified in vertebrates. All belonging to the tyrosine kinase superfamily. In this manuscript, the focus is based on an analysis of the role of FGF receptor signaling pathways and aberrations especially in pediatric diseases. Erk 1 and Erk 2 seem to have an important role as a mediator of FGF signaling in different biological and developmental processes. FGF signaling plays an important role in conserved developmental functions in skeletal growth, palate closure, ear development, cranial suture ossification and neuronal development in the child. Aberrant FGF signaling causes different congenital disorders and different forms of cancer in childhood. Modulating FGF signaling is of great importance for the treatment of rare diseases in childhood.

Genomic Profiling and Molecular Characterisation of Metastatic Urothelial Carcinoma.

The clinical management of metastatic urothelial carcinoma (mUC) is undergoing a major paradigm shift; the integration of immune checkpoint inhibitors (ICIs) and antibody-drug conjugates (ADCs) into the mUC therapeutic strategy has succeeded in improving platinum-based chemotherapy outcomes. Given the expanding therapeutic armamentarium, it is crucial to identify efficacy-predictive biomarkers that can guide an individual patient's therapeutic strategy. We reviewed the literature data on mUC genomic alterations of clinical interest, discussing their prognostic and predictive role. In particular, we explored the role of the fibroblast growth factor receptor (FGFR) family, epidermal growth factor receptor 2 (HER2), mechanistic target of rapamycin (mTOR) axis, DNA repair genes, and microsatellite instability. Currently, based on the available clinical data, FGFR inhibitors and HER2-directed ADCs are effective therapeutic options for later lines of biomarker-driven mUC. However, emerging genomic data highlight the opportunity for earlier use and/or combination with other drugs of both FGFR inhibitors and HER2-directed ADCs and also reveal additional potential drug targets that could change mUC management.

Paradoxical cancer cell proliferation after FGFR inhibition through decreased p21 signaling in FGFR1-amplified breast cancer cells

Fibroblast growth factors (FGFs) control various cellular functions through fibroblast growth factor receptor (FGFR) activation, including proliferation, differentiation, migration, and survival. FGFR amplification in ER + breast cancer patients correlate with poor prognosis, and FGFR inhibitors are currently being tested in clinical trials. By comparing three-dimensional spheroid growth of ER + breast cancer cells with and without FGFR1 amplification, our research discovered that FGF2 treatment can paradoxically decrease proliferation in cells with FGFR1 amplification or overexpression. In contrast, FGF2 treatment in cells without FGFR1 amplification promotes classical FGFR proliferative signaling through the MAPK cascade. The growth inhibitory effect of FGF2 in FGFR1 amplified cells aligned with an increase in p21, a cell cycle inhibitor that hinders the G1 to S phase transition in the cell cycle. Additionally, FGF2 addition in FGFR1 amplified cells activated JAK-STAT signaling and promoted a stem cell-like state. FGF2-induced paradoxical effects were reversed by inhibiting p21 or the JAK-STAT pathway and with pan-FGFR inhibitors. Analysis of patient ER + breast tumor transcriptomes from the TCGA and METABRIC datasets demonstrated a strong positive association between expression of FGF2 and stemness signatures, which was further enhanced in tumors with high FGFR1 expression. Overall, our findings reveal a divergence in FGFR signaling, transitioning from a proliferative to stemness state driven by activation of JAK-STAT signaling and modulation of p21 levels. Activation of these divergent signaling pathways in FGFR amplified cancer cells and paradoxical growth effects highlight a challenge in the use of FGFR inhibitors in cancer treatment.

Expression of fibroblast growth factor receptor 2 (FGFR2) in combined hepatocellular-cholangiocarcinoma and intrahepatic cholangiocarcinoma: clinicopathological study

Genetic alterations including fusions in fibroblast growth factor receptor 2 (FGFR2) are detected in 10–20% of intrahepatic cholangiocarcinoma (iCCA), and FGFR2 inhibitors are effective for the treatment of iCCA. We examined a prevalence of FGFR2 genetic alterations and their clinicopathological significance in combined hepatocellular–cholangiocarcinoma (cHCC-CCA). FGFR2 expression, which is a surrogate marker for FGFR2 genetic alterations, was immunohistochemically assessed in the liver sections from 75 patients with cHCC-CCA, 35 with small duct-type iCCA, 30 with large duct-type iCCA, and 35 with hepatocellular carcinoma (HCC). FGFR2 genetic alterations were detected by reverse transcription-PCR and direct sequence. An association of FGFR2 expression with clinicopathological features was investigated in cHCC-CCAs. FGFR2 expression was detected in significantly more patients with cHCC-CCA (21.3%) and small duct-type iCCA (25.7%), compared to those with large duct-type iCCA (3.3%) and HCC (0%) (p < 0.05). FGFR2-positive cHCC-CCAs were significantly smaller size (p < 0.05), with more predominant cholangiolocarcinoma component (p < 0.01) and less nestin expression (p < 0.05). Genetic alterations of ARID1A and BAP1 and multiple genes were significantly more frequent in FGFR2-positive cHCC-CCAs (p < 0.05). 5′/3′ imbalance in FGFR2 genes indicating exon18-truncated FGFR2 was significantly more frequently detected in FGFR2-positive cHCC-CCAs and small duct iCCAs, compared to FGFR2-negative ones (p < 0.05). FGFR2::BICC fusion was detected in a case of cHCC-CCAs. FGFR2 genetic alterations may be prevalent in cHCC-CCAs as well as small duct-type iCCAs, which suggest cHCC-CCAs may also be a possible therapeutic target of FGFR2 inhibitors.Graphical

Discovery of a novel homoisoflavonoid derivative 5g for anti-osteoclastic bone loss via targeting FGFR1

Several flavonoids have been shown to exert anti-osteoporosis activity. However, the structure-activity relationship and the mechanism of anti-osteoporosis activity of flavonoids remain unknown. In this study, we prepared a series of novel homoisoflavonoid (HIF) derivatives to evaluate their inhibitory effects on osteoclastogenesis using TRAP-activity in vitro assay. Then, the preliminary structure-activity relationship was studied. Among the evaluated novel flavonoids, derivative 5g exerted the most inhibitory bioactivity on primary osteoclast differentiation without interfering with osteogenesis. It was hence selected for further in vitro, in vivo and mechanism of action investigation. Results show that 5g likely directly binds to the fibroblast growth factor receptor 1 (FGFR1), decreasing the activation of ERK1/2 and IκBα/NF-κB signaling pathways, which in turn blocks osteoclastogenesis in vitro and osteoclastic bone loss in vivo. Our study shows that homoisoflavonoid (HIF) derivatives 5g can serve as a potential novel candidate for treating osteoporosis via inhibition of FGFR1.

Population pharmacokinetic-pharmacodynamic modeling of serum biomarkers as predictors of tumor dynamics following lenvatinib treatment in patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC).

Lenvatinib is a receptor tyrosine kinase (RTK) inhibitor targeting vascular endothelial growth factor (VEGF) receptors 1-3, fibroblast growth factor (FGF) receptors 1-4, platelet-derived growth factor receptor-α (PDGFRα), KIT, and RET that have been implicated in pathogenic angiogenesis, tumor growth, and cancer. The primary objective of this work was to evaluate, by establishing quantitative relationships, whether lenvatinib exposure and longitudinal serum biomarker data (VEGF, Ang-2, Tie-2, and FGF-23) are predictors for change in longitudinal tumor size which was assessed based on data from 558 patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC) receiving either lenvatinib or placebo treatment. Lenvatinib PK was best described by a 3-compartment model with simultaneous first- and zero-order absorption and linear elimination from the central compartment with significant covariates (body weight, albumin <30 g/dL, ALP>ULN, RR-DTC, RCC, HCC subjects, and concomitant CYP3A inhibitors). Except for body weight, none of the covariates have any clinically meaningful effect on exposure to lenvatinib. Longitudinal biomarker measurements over time were reasonably well defined by a PK/PD model with common EC50, Emax, and a slope for disease progression for all biomarkers. Longitudinal tumor measurements over time were reasonably well defined by a tumor growth inhibition Emax model, which in addition to lenvatinib exposure, included model-predicted relative changes from baseline over time for Tie-2 and Ang-2 as having significant association with tumor response. The developed PK/PD models pave the way for dose optimization and potential prediction of clinical response.

Abstract 5099: Prevalence of fibroblast growth factor receptor (FGFR) alterations (alts) and programmed death-ligand 1 (PD-L1) expression (exp) in Chinese solid tumor patients (pts)

Abstract Background: PD-L1 expression drives anti-PD(L)-1 treatment decisions across many cancer indications. FGFR inhibitors have been approved for the treatment of metastatic urothelial cancer (UC) and cholangiocarcinoma with FGFR alts. BALVERSA (erdafitinib), a selective pan-FGFR kinase inhibitor, has shown clinical activity against FGFR altered solid tumors in pts who exhausted standard treatment options. It is important to understand the prevalence of FGFR alts and relationship between FGFR alts and PD-L1 expression levels in different cancer types. Methods: In this real-world study, 9937 Chinese solid tumor pts with the PD-L1 (22C3) immunohistochemistry and OrigiMed 450-gene next-generation sequencing panel results were selected. Chi-square test and Fisher test were used to explore the association between the FGFR alts and PD-L1 expression. Results: FGFR1-4 somatic alts were found in 9.0% of Chinese cancer pts evaluated. FGFR1 amplification (amp) was the most prevalent alts identified (1.9%). There were no significant differences in frequency of FGFR alts between the Chinese cohort and MSK-IMPACT cohort in each cancer type tested. Up to 40.6% of pts evaluated were PD-L1 positive (CPS ≥1 or TPS ≥1%). The PD-L1 positive rate (TPS ≥1%) in SCLC (12.4%, n=121) and NSCLC adenocarcinoma tumors (LUAD) (26.1%, n=2902) was relatively low. In few tumor types, higher expression of PD-L1 in FGFR altered samples was observed compared with FGFR unaltered samples in pan-tumor (mean TPS 14.8% vs.8.6%, P=6.0*E-9; mean CPS 6.3 vs. 6.1, P=3*E-4). Those includes LUAD (mean TPS 14.2% vs. 7.4%, P = 1.7*E-16), colorectal tumor (mean CPS 4.6 vs. 3.9, P = 4.6*E-8), and uterine tumor (mean CPS 8.1 vs. 6.5, P = 9.6*E-5). While PD-L1 expression is lower in FGFR altered samples than FGFR unaltered samples in UC (n=154; mean CPS 3.9 vs. 6.8, P = 0.004). No relationship was observed between FGFR alts and PD-L1 expression in cholangiocarcinoma (n=610). Specific FGFR alts eligible for erdafitinib UC treatment were further investigated in UC and observed with rate 10.4%, including FGFR3 short variants (9.7%) as main alts. Specific FGFR altered tumors showed similar trend with lower PD-L1 expression than FGFR unaltered tumors in UC. The inverse relationship between FGFR alts and PD-L1 expression in UC compared to other solid tumors may explain variable role of FGFRs since the predominant FGFR alt types vary among different cancer types (FGFR3 short variants enriched in UC vs no such predominant FGFR alt types in other cancer types). Conclusion: The large Chinese solid tumor cohort analysis showed comparable FGFR alts prevalence between Chinese and Western population. Differences in relationship between FGFR alts and PD-L1 expression across tumor types reflect the differential role of predominant FGFR types in each tumor type. Citation Format: Min Qing, Fei Yang, Xiaowei Chen, Xuesong Lyu, Aodi Wang, Yanfei Yu, Shibu Thomas, Longen Zhou. Prevalence of fibroblast growth factor receptor (FGFR) alterations (alts) and programmed death-ligand 1 (PD-L1) expression (exp) in Chinese solid tumor patients (pts) [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 5099.

Abstract 1035: Identification of fibroblast growth factor receptors (FGFRs) alterations (alts) at DNA and RNA-level by one-step next-generation sequencing (NGS) panel

Abstract Background: FGFR inhibitors are currently in clinical development or approved for urothelial cancer and cholangiocarcinoma with FGFR fusion (FUS) or/and mutation (MUT). AmoyDx FGFR 1-4 NGS Panel (FGFR-P) was developed for FGFR alts detection based on both DNA and RNA. The goal of this study is to validate and assess the performance of FGFR-P in pan-cancer FGFR alts detection by comparing with an AmoyDx comprehensive genomic profiling test (CGP) and a health authority approved DNA-based NGS panel (DNA-P). Methods: Both FGFR-P and CGP are DNA (MUT) and RNA (FUS) based for detecting FGFR alts with optimized bioinformatics pipeline to eliminate baseline noise caused by deamination events, which is commonly found in aged FFPE samples. Cell lines, cell line/patient derived xenografts (CDXs/PDXs) and 397 samples of 26 cancer types (90 samples &amp;gt;10 years) were used for validation of FGFR-P. Total 382 and 50 pan-cancer samples were respectively tested to compare FGFR-P with CGP and DNA-P. Results: To validate accuracy, 36 FFPE samples from cell lines and CDXs/PDXs with known FGFR status (25 FUSs, 5 MUTs, 6 wild-types) were tested by FGFR-P with concordance rate 100%. In clinical sample testing, FGFR-P also showed high agreement with CGP (99.5%) and DNA-P (98.0%). Conflicting result confirmed by FISH revealed 1 FUS missed by DNA-P but detected by FGFR-P, which demonstrated advantage of FGFR alts detection by DNA+RNA. In addition, an optimized bioinformatics pipeline by mimic samples with deamination events effectively filtered out C:G&amp;gt;T:A false positive signals. FGFR-P achieved high success rate in testing pan-tumor samples (89.9%) including samples &amp;gt;10 years (75.6%). Conclusions: FGFR-P provides a novel opportunity to identify FGFR alt pan-cancer patients using a robust DNA+RNA NGS platform, which shows high success rate even in aged samples and will be a potent tool for sensitive and reliable detection of FGFR alts for clinical diagnostics. CGP FGFR-P MUT Positive Negative Total Positive 29 0 29 Negative 1 194 195 Total 30 194 224 FUS Positive Negative Total Positive 20 1 21 Negative 0 137 137 Total 20 138 158 The overall percent agreement 99.5% Citation Format: Min Qing, Xuejun Chen, Wenqing Su, Xiaofang Zhuo, Ting Shen, Chengjuan Xiong, Xuesong Lyu, Renee Tate, Qibiao Wu, Longen Zhou, Shibu Thomas, Wangwang Ning, Jianqing Wang, Huihui Yan, Zhiqiang Yin, Zhan Huang, Yaxin Xue, Changbin Zhu. Identification of fibroblast growth factor receptors (FGFRs) alterations (alts) at DNA and RNA-level by one-step next-generation sequencing (NGS) panel [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 1035.

Abstract 3755: Impact of antigen retrieval and other parameters on detection of FGFR2b in various solid tumors on a BenchMark ULTRA automated staining platform: Development of a new IHC assay for FGFR2b

Abstract Background: Fibroblast growth factor receptor 2b (FGFR2b) is part of the FGFR transmembrane tyrosine kinase receptor family. This protein has gained more attention in recent years as a tumor progression biomarker in numerous solid tumors. The detection of FGFR2b by immunohistochemistry (IHC) has been used recently in immunotherapy clinical trials with multiple tumor types. During IHC assay development on formalin-fixed paraffin embedded tissue, a thorough study of antigen retrieval through cell conditioning or enzyme incubation, primary antibody incubation, and detection parameters is critical to evaluate staining performance. Design: A study of an investigational anti-FGFR2b (FPR2-D) assay developed on a BenchMark ULTRA automated staining platform explored the effect of antigen retrieval and detection parameters on staining performance. VENTANA System Software was used to modify steps in the IHC staining protocol resulting in 42 permutations. Ten different solid tumors were stained with these modifications to the assay and subsequently evaluated for FGFR2b expression. Result:s The results demonstrate that the staining clarity, intensity, and dynamic range within tissue cases of FGFR2b staining can vary widely between different solid tumor types. While most permutations of the initial assay parameters had minimal impact on the staining performance and readability by a pathologist, the order of the enzyme treatment and the cell conditioning steps (in addition to increased incubation time of primary antibody) had a significant impact when comparing across different solid tumors. Detection of FGFR2b seemed to have a greater susceptibility by tumor type to the antigen retrieval process than has traditionally been observed in other biomarkers. Conclusion: The overall results of this investigation show the importance of an extensive parameter screening approach when evaluating new antibody targets and indication combinations in IHC to ensure optimal staining performance. This is critical to downstream testing and the potential use of new assays in the context of in vitro diagnostics. Citation Format: Autumn Sky Watson, Catherine Le, Anne M. Wertheimer, Spencer Escobedo, Lisa So, Bhavani Bagevalu Siddegowda, John D. Palting, Susan Marion, Steven P. Stratton, Birte Aggeler. Impact of antigen retrieval and other parameters on detection of FGFR2b in various solid tumors on a BenchMark ULTRA automated staining platform: Development of a new IHC assay for FGFR2b [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 3755.

Abstract 643: Analysis of the effect of FGFR inhibitor and cannabidiol in colorectal cancer

Abstract Introduction: Colorectal cancer (CRC) remains a serious health problem worldwide. In particular, in the case of stage 4 metastatic cancer, a cure can be expected as multidisciplinary treatment is possible by combining surgery, chemotherapy, and the development of targeted anticancer drugs, but there is still no type of treatment available. It is limited. FGFR (Fibroblast Growth Factor Receptor) has emerged as an important anticancer target in various malignant tumors, and small molecule-based targeted treatments have been developed and clinical trials are underway, and some colon cancer patients are known to have FGFR genetic alterations. Cannabidiol (CBD), a non-psychoactive cannabinoid, has recently been reported to be associated with the ability to induce cell death through various signaling systems in colon cancer, and has anticancer effects and mechanisms related to overcoming anticancer drug resistance. has been identified. Therefore, we sought to analyze the effect of FGFR inhibitors on colon cancer, explore the possibility of developing them as new target substances, and find ways to increase anticancer effects by confirming the effects of combination with cannabidiol (CBD) and related mechanisms. Method: Cell survival was confirmed through the WST-1 assay, an assay for measuring cell viability. The signaling pathway was identified through western blot. Data were compared using two-tailed Student’s t-test or one-way analysis of variance and Tukey’s post hoc test. Result: The FGFR expression pattern was confirmed in various cancer cell lines, and NCI-H716 was confirmed to have high FGFR2 expression in the colorectal cancer cell line. (Figure 1) As a result of treating CBD 4uM and AZD 10nM (Cell proliferation, apoptosis, western blot), cell death occurred more clearly when treated together than when treated alone, confirming the effectiveness of the combination. (Figure 2) An increase in apoptosis of NCI-H716 cells was confirmed when CBD and AZD 4547 were combined. (Figure 3) Through a heatmap of differentially expressed genes in RNA sequencing, it was estimated that ER stress may be related to the combination effect. (Figure 4) The relationship between ER stress and the combination of CBD and AZD 4547 on apoptosis of NCI-H716 cells was confirmed. (Figure 5) Conclusion: It was confirmed that the combined effect of FGFR inhibitor and cannabidiol was effective in colorectal cancer cells, and it was assumed to be related to the ER stress pathway. Citation Format: Yeonuk Ju, Wooyoung Kim, Bugyeom Kim, Jiyoung Kim, Junwoo Bong, Chinock Cheong, Sanghee Kang, Byung Wook Min, Sang Cheul Oh, Sun Il Lee. Analysis of the effect of FGFR inhibitor and cannabidiol in colorectal cancer [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 643.

Abstract 6497: Molecular characterization and drug sensitivity of a gastric FGFR2-TACC2 and a pancreatic KRAS p.G12C primary culture

Abstract Introduction and Objectives: Gastric and pancreatic cancers lack effective therapies, leading to low survival rates particularly in the metastatic setting. Fibroblast growth factor receptor 2 (FGFR2) amplification and fusions with TACC2 appear in 5.5% and 2.1% of gastric tumors, respectively. In pancreatic cancers, the KRAS p.G12C mutation is limited to 1-2% of cases. FDA has recently approved drugs targeting both alterations, pemigatinib and infigratinib for cholangiocarcinoma with FGFR2 fusions; sotorasib and adagrasib for KRAS p.G12C mutant lung cancers. Here, we report the initiation of primary cultures that can be used as preclinical models for testing antitumor agents in gastric and pancreatic tumor cells. Materials and Methods: Pleural effusions were collected from a gastric and a pancreatic cancer patient, both metastatic. Cells were isolated by centrifugation, cultured for 2-3 months in complete medium and genotyped using next generation sequencing (NGS) and RNA nCounter hybridization. Primary cultures were treated with specific drugs depending on their molecular alterations and clinical guidelines. Cell viability was determined by MTT. Results: Tumor cells from the pleural effusion of the gastric cancer patient were grown in suspension. NGS and nCounter revealed a FGFR2-TACC2 fusion, a FGFR2 amplification (160 copies) and a TP53 p.G245S mutation (100% variant allele fraction, VAF). The fusion and the amplification were confirmed by FISH. Cells were sensitive to erdafitinib, with IC50=40 nM in MTT assays. Irinotecan, 5-fluorouracil and cisplatin were also tested; IC50 were below the described plasma Cmax in the first two cases. The patient was treated with first-line fluoropyrimidine and oxaliplatin with partial response and a 5-month progression-free survival. Due to rapid deterioration, 2nd line treatment was not administered. The tumor cells from the pancreatic cancer patient were adherent, NGS revealed a KRAS amplification (9 copies) accompanied by a KRAS p.G12C mutation (81% VAF) and a TP53 p.R175H mutation (99% VAF). MTT assays were performed to determine the cells’ response to oxaliplatin, 5-fluorouracil, irinotecan, gemcitabine, nab-paclitaxel, adagrasib and sotorasib. IC50s below plasma Cmax were found in the last three cases. Remarkably, the IC50 for sotorasib was 100 nM and for adagrasib was 300 nM. The patient was treated with first-line gemcitabine and nab-paclitaxel with partial response but discontinued after three months due to hematological toxicity. Conclusions: Primary cultures can be initiated from malignant pleural effusions and used for genetic characterization and drug sensitivity profiling. Primaries with specific alterations can be employed as preclinical models to test targeted therapies. Citation Format: Silvia Garcia-Roman, Ekaterina Meshoulam Nikolaeva, Juan José García Mosquera, Mónica Garzón Ibáñez, Ruth Roman, Sonia Rodríguez, Cristina Rodríguez, Clara Mayo de las Casas, Rafael Rosell, Miguel A. Molina-Vila, Cristina Aguado Esteban. Molecular characterization and drug sensitivity of a gastric FGFR2-TACC2 and a pancreatic KRAS p.G12C primary culture [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 6497.

Multiple receptor tyrosine kinases regulate dengue infection of hepatocytes.

Dengue is an arboviral disease causing severe illness in over 500,000 people each year. Currently, there is no way to constrain dengue in the clinic. Host kinase regulators of dengue virus (DENV) infection have the potential to be disrupted by existing therapeutics to prevent infection and/or disease progression. To evaluate kinase regulation of DENV infection, we performed kinase regression (KiR), a machine learning approach that predicts kinase regulators of infection using existing drug-target information and a small drug screen. We infected hepatocytes with DENV in vitro in the presence of a panel of 38 kinase inhibitors then quantified the effect of each inhibitor on infection rate. We employed elastic net regularization on these data to obtain predictions of which of 291 kinases are regulating DENV infection. Thirty-six kinases were predicted to have a functional role. Intriguingly, seven of the predicted kinases - EPH receptor A4 (EPHA4), EPH receptor B3 (EPHB3), EPH receptor B4 (EPHB4), erb-b2 receptor tyrosine kinase 2 (ERBB2), fibroblast growth factor receptor 2 (FGFR2), Insulin like growth factor 1 receptor (IGF1R), and ret proto-oncogene (RET) - belong to the receptor tyrosine kinase (RTK) family, which are already therapeutic targets in the clinic. We demonstrate that predicted RTKs are expressed at higher levels in DENV infected cells. Knockdown of EPHB4, ERBB2, FGFR2, or IGF1R reduces DENV infection in hepatocytes. Finally, we observe differential temporal induction of ERBB2 and IGF1R following DENV infection, highlighting their unique roles in regulating DENV. Collectively, our findings underscore the significance of multiple RTKs in DENV infection and advocate further exploration of RTK-oriented interventions against dengue.

Abstract 2025: Zeb1 downregulation sensitizes pancreatic cancer-associated fibroblasts to killing by oncolytic reovirus through upregulation of the reovirus receptor junction adhesion molecule A

Abstract Pancreatic tumors display an abundance of cancer-associated fibroblasts (CAFs), which negatively affect prognosis and therapy response. Oncolytic virotherapy exploits viruses that preferentially lyse epithelial cancer cells as opposed to normal cells. Interestingly, we have observed that oncolytic reoviruses are able to infect and lyse CAFs, in addition to epithelial cancer cells. Targeting CAFs, in addition to cancer cells, could be advantageous to increase therapy effectiveness. It could serve as a conduit for viral spread and simultaneously disrupt the desmoplastic barrier around tumors, thereby also accelerating the influx of other therapeutics and immune cells. We previously found that the proneness of CAFs to lysis by oncolytic reovirus correlates with the cell surface expression levels of the reovirus entry receptor junction adhesion molecule A (JAM-A). However, most pancreatic CAFs do not express JAM-A. Therefore, a genome-wide CRISPR/Cas9 screen was employed to identify the genes regulating JAM-A expression on fibroblasts, which can subsequently be targeted to sensitize CAFs to reovirus. Pancreatic stellate cells with a moderate JAM-A expression level were transduced with a gRNA library making a knockout of one gene per cell. The highest and lowest JAM-A expressing cells were sorted and sequenced to identify the gRNAs that regulate JAM-A expression. Clonal CRISPR/Cas9-generated knockouts of a top negative regulator were generated and infected with reovirus, followed by cell viability assays to quantify their susceptibilities to reovirus-induced cell death. F11R, the gene encoding JAM-A, was identified as the top positive regulator of JAM-A expression in the CRISPR/Cas9 screen, verifying the validity of the screen. The top negative regulators identified were Fibroblast Growth Factor Receptor 1 (FGFR1) and Zinc finger E-box Binding homeobox 1 (Zeb1), thereby serving as potential therapeutic targets to sensitize CAFs to reovirus treatment. Using clonal Zeb1 knock-outs, Zeb1 was confirmed as a strong regulator of JAM-A expression. Zeb1 knockout in JAM-A negative pancreatic fibroblasts caused a robust upregulation of JAM-A and sensitized these inherently resistant fibroblasts to reovirus-directed cytolysis. Additionally, the clinically approved drug Mocetinostat, previously described to inhibit Zeb1, upregulated JAM-A expression on CAFs and increased cell lysis by reovirus. Altogether, our data show that Zeb1 is a strong negative regulator of JAM-A expression on fibroblasts and that Zeb1 inhibition can sensitize CAFs to reovirus-induced cell death. This research provides a rationale for combining Zeb1 inhibitory drugs with oncolytic reovirus treatment to improve killing of CAFs, which in turn could boost overall tumor eradication. Citation Format: Nicole Dam, Tom J. Harryvan, Bernhard Schmierer, Lukas J.A.C. Hawinkels, Vera Kemp. Zeb1 downregulation sensitizes pancreatic cancer-associated fibroblasts to killing by oncolytic reovirus through upregulation of the reovirus receptor junction adhesion molecule A [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 2025.

Abstract 2126: Efficacy and underlying mechanisms of surufatinib in non-small cell lung cancer treatment

Abstract Background: The prevalence and fatality of lung cancer, especially non-small cell lung cancer (NSCLC), highlight the urgency for efficacious therapies. Surufatinib, an inhibitor of tyrosine kinases like VEGF receptors (VEGFR) 1, 2, and 3, Fibroblast growth factor receptor 1 (FGFR1), and CSF-1R, shows potential in augmenting chemotherapy efficacy and reducing adverse effects. Preliminary clinical studies (NCT04922658) have indicated survival benefits for NSCLC patients treated with surufatinib. This investigation seeks to delineate the therapeutic efficacy of surufatinib, correlating clinical benefits with mechanistic insights. Methods: To elucidate mechanisms, proliferation assays (CCK8), migration (scratch assay), and apoptosis (flow cytometry) were conducted in A549 and H1299 cell lines. Angiogenesis and macrophage polarization were examined via vascular junction points and mRNA expression profiling. In nude mice, subcutaneous tumors were induced and treated with the study drugs, with tumor growth and angiogenic markers assessed. Results: In vitro, surufatinib potently inhibited angiogenesis and exerted a dose-dependent suppression of proliferation and colony formation in lung cancer A549 and PC9 cell lines. It also enhanced apoptosis and cell migration. Additionally, surufatinib shifted macrophage polarization towards an M1 phenotype while diminishing M2 macrophages, thereby, contributing to a more robust anti-tumor immune milieu. In vivo studies corroborated these findings, with surufatinib and vinorelbine combination therapy significantly curtailing tumor growth and reducing CD31 expression in tumor tissues, highlighting its potential for substantial therapeutic gains in NSCLC management. Conclusion: Surufatinib achieved notable antitumor effect consistent with clinical findings in NSCLC, effectively inhibiting cellular proliferation and migration, attenuating angiogenesis, and enhancing apoptosis. Significantly, it also modulated macrophage polarization to favor an M1/M2 balance, thus activating the immune response. Therapeutic strategies with surufatinib have underscored augmented antineoplastic efficacy, meriting additional clinical investigations. Citation Format: Yanfang Zheng, Binjie Shan, Meng Wang, Xiaoran Wu, Rui Cai, Feiyu Niu, Yan Yuan, Lu Liu, Xiongjie Zhu. Efficacy and underlying mechanisms of surufatinib in non-small cell lung cancer treatment [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 2126.

Abstract 4736: Evaluate the potential sensitization effect and underlying mechanism of lenvatinib on cisplatin resistance oral squamous cell carcinoma

Abstract Oral squamous cell carcinoma (OSCC) is a prevalent form of cancer that develops in the oral cavity, globally recognized as the eighth most commonly diagnosed cancer. Despite the application of standard surgical techniques or concurrent chemoradiotherapy, the prognosis for OSCC patients remains unsatisfactory. Initially, cisplatin, the primary and most frequently used chemotherapy agent for treating OSCC, demonstrates effectiveness in therapy. Nonetheless, chemoresistance frequently arises, leading to treatment failure, and this is intricately associated with the activation of hypoxia-inducible factor 1α (HIF-1α) signaling. Recent research has brought to light heightened levels of HIF-1α-mediated vascular endothelial growth factor (VEGF) and BCL-2 in OSCC tumor sites, which play crucial roles in regulating angiogenesis and anti-apoptotic processes within cancer cells. Additionally, interventions aimed at targeting anti-apoptotic molecules or augmenting the expression of pro-apoptotic molecules may represent promising strategies to overcome chemoresistance in OSCC. Therefore, HIF-1α/VEGF/BCL-2 axis could be considered a potential target for the development of chemopreventive and chemotherapeutic strategies for OSCC. Lenvatinib is a targeted multi-kinase inhibitor that can inhibit tumor growth and angiogenesis by blocking the activation of vascular endothelial growth factor receptor (VEGFR) 1-3, fibroblast growth factor receptor (FGFR) 1-4, platelet-derived growth factor receptor (PDGFR) α, as well as the proto-oncogenes RET and KIT. However, whether lenvatinib may sensitizes OSCC to cisplatin remains unclear. In our study, we used the MTT assay to prove the cytotoxicity of OSCC cells (SAS and MOC1 cells) was induced by cisplatin and lenvatinib. We employed flow cytometry to verify that the combination of lenvatinib and cisplatin can indeed trigger both extrinsic and intrinsic apoptotic pathways in OSCC cells. Furthermore, our demonstration revealed that the induction of apoptosis pathways by the combination of lenvatinib and cisplatin is associated with mitochondrial-dependent apoptosis and death receptor-dependent apoptosis. Then, transwell invasion and migration assay results proved the inhibition effect of lenvatinib combined with cisplatin in SAS and MOC1 cells. Furthermore, we indicated that the combination of lenvatinib and cisplatin can effectively inhibit angiogenesis and anti-apoptotic mechanisms mediated by the HIF-1α/VEGF/BCL-2 axis in OSCC cells. In summary, our results demonstrate that the combined treatment with lenvatinib and cisplatin enhances the response of OSCC cells under hypoxic conditions. Additionally, it aims to mitigate the negative impact of hypoxia on cisplatin's therapeutic effectiveness and increase the sensitivity of OSCC cells to cisplatin. Citation Format: Ying-Tzu Chen, Yan-Ting Tsai, Fei-Ting Hsu, Hsi-Feng Tu. Evaluate the potential sensitization effect and underlying mechanism of lenvatinib on cisplatin resistance oral squamous cell carcinoma [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 4736.

Abstract 5582: Discovery and preclinical characterization of ISM8001, a covalent and selective FGFR2/FGFR3 dual inhibitor with strong monotherapy anti-tumor activity against advanced solid tumors

Abstract Oncogenic alterations in fibroblast growth factor receptors 2 and 3 (FGFR2 and FGFR3) are key drivers in intrahepatic cholangiocarcinoma, urothelial carcinoma and multiple other solid tumors. Currently approved pan-FGFR inhibitor therapy is limited by off-isoform toxicity (FGFR1-mediated hyperphosphatemia and FGFR4-mediated diarrhea) and acquired FGFR2 or FGFR3 kinase domain resistance mutations. The second generation of FGFR inhibitors currently undergoing clinical evaluation such as RLY-4008 and LOXO-435 are primarily focused on achieving selectivity against either the FGFR2 or FGFR3 isoform, which may narrow their clinical potential. To overcome this limitation and to allow a favorable toxicity profile, we designed and evaluated the anti-cancer effects of a novel and selective FGFR2/FGFR3 dual inhibitor, ISM8001. Biochemically, ISM8001 showed superior inhibition against FGFR2 and FGFR3 with &amp;gt;90-fold and &amp;gt;800-fold selectivity of FGFR2 over FGFR1 and FGFR4, respectively. As an irreversible inhibitor, ISM8001 displayed strong affinity and high efficiency of covalent bond formation with FGFR2/3. Additionally, ISM8001 showed broad inhibition against multiple FGFR2/3 mutant isoforms, especially gatekeeper mutation (FGFR2-V564F and FGFR3-V555M). ISM8001 inhibited cell proliferation of multiple human cancer cell lines with FGFR2/3 aberration with IC50 &amp;lt;10 nM while IC50 &amp;gt;1 µM was observed in cell lines without FGFR2/3 alterations. Furthermore, ISM8001 demonstrated robust in vivo anti-tumor efficacy in multiple cell line-derived xenograft mouse models including the SNU-16 gastric cancer model (FGFR2-amplification), the AN3CA endometrial cancer model (FGFR2 N549K mutation) and the RT4 bladder cancer model (FGFR3-fusion), with tumor growth inhibition varying from 80%~120% while no significant serum phosphate increase or body weight loss. ISM8001 also displayed strong anti-tumor effects in xenograft models of Ba/F3-FGFR2/3 engineered cell lines with different gatekeeper mutations. ISM8001 is classified as a BCS II compound with favorable DMPK properties and druggability, high permeability, low efflux ratio and low DDI risk. In vivo PK profiles showed moderate to low clearance and high oral bioavailability across preclinical species. In addition, ISM8001 showed a promising in vitro safety profile with favorable selectivity in 468-kinase and Cerep-44 panel studies, and no hERG concerns. Results of 28-day non-clinical toxicology studies in rat and dog showed a safety window of approximately 2-5 fold based on efficacious exposure in different models. Taken together, these data support the clinical development of ISM8001 as a novel, selective FGFR2/FGFR3 dual inhibitor for the potential tissue-agnostic therapy of advanced solid tumors with FGFR2/3 aberrations. Citation Format: Yihong Zhang, Yazhou Wang, Xin Cai, Jinxin Liu, Hui Cui, Junwen Qiao, Xiaoxia Lin, Xiao Ding, Supriya Bavadekar, Sujata Rao, Man Zhang, Feng Ren, Alex Zhavoronkov. Discovery and preclinical characterization of ISM8001, a covalent and selective FGFR2/FGFR3 dual inhibitor with strong monotherapy anti-tumor activity against advanced solid tumors [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 5582.

Abstract 638: FGFR4 mediates nuclear accumulation of NRF2 by binding to P62 in gastric cancer

Abstract Background: Helicobacter pylori (H. pylori) is the major cause of gastric cancer. Fibroblast growth factor receptor 4 (FGFR4) is a member of the highly conserved tyrosine kinase family known to be activated in cancer. Nuclear Factor Erythroid 2-Related Factor 2 (NRF2), a transcription factor, is essential for the antioxidant response and exhibits cytoprotective properties against cellular stress and oxidative damage. This study investigates the novel functions of FGFR4 and its role in regulating the antioxidant response in gastric tumorigenesis. Methods: We used public datasets, gastric tissues from mice and human, and gastric cancer cell lines. In vitro and in vivo H. pylori infections were performed. Western blot, RT-qPCR, Immunofluorescence, flow cytometry, Immunohistochemistry, Immunoprecipitation, Proximity ligation assay and Luciferase reporter assays were performed. Results: The analysis of a public dataset revealed that overexpression of FGFR4 is associated with an oxidative stress signature and poor survival. Gene set enrichment analysis (GSEA) showed that tissue samples with high FGFR4 levels had an enrichment of NRF2 signature genes. In vitro cell models infected with H. pylori showed an increase in reactive oxygen species (ROS). Knockdown of FGFR4 resulted in significant reductions in NRF2 protein and transcriptional activity, leading to increased ROS levels and DNA damage. Immunofluorescence analysis using various models confirmed that FGFR4 knockdown reversed the accumulation of NRF2 in the nucleus. Dysplastic and neoplastic gastric lesions in the TFF1-KO mouse model exhibited high levels of both FGFR4 and NRF2. Pharmacologic inhibition or knockdown of FGFR4 significantly decreased NRF2 levels, as well as the size and number of gastric cancer spheroids. Mechanistically, elevated levels of P62 protein were associated with FGFR4 expression. Binding between FGFR4 and P62 proteins, which competes with NRF2-KEAP1 interaction, was detected using immunoprecipitation and proximity ligation assay. Immunohistochemistry analysis on a tissue microarray showed increased FGFR4 immunostaining in HGD/Cancer samples compared to adjacent normal samples, and this increase correlated with an increase in NRF2 and P62 levels. Conclusion: These findings revealed that FGFR4 has a distinct functional role in promoting gastric carcinogenesis. FGFR4 binds to P62 to inhibit the interaction between NRF2 and KEAP1, allowing NRF2 to avoid degradation facilitating its translocation and accumulation in the nucleus. The use of FGFR4 inhibitors is a viable treatment option that warrants further research in patients with gastric cancer. Citation Format: Nadeem S. Bhat, Mohammed Soutto, Xing Zhang, Zheng Chen, Shoumin Zhu, Selma Maacha, Melanie Genoula, Dunfa Peng, Heng Lu, Oliver G McDonald, Xi Steven Chen, Longlong Cao, Zekuan Xu, Wael El-Rifai. FGFR4 mediates nuclear accumulation of NRF2 by binding to P62 in gastric cancer [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 638.