Human Non-small Cell Lung Cancer Research Articles

Abstract 2779: The significance of TIMP-1 and hypoxia in cancer stemness: A synergistic role in chemoresistance

Abstract Chemotherapeutic resistance in non-small-cell lung cancer (NSCLC) poses a formidable clinical challenge. Numerous studies have highlighted the critical role of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in tumorigenesis and, increasingly, in the development of chemoresistance. We have studied multiple aspects of the MMP-independent, tumor-promoting function of TIMP1 in human NSCLC. Our recent studies have found a pivotal role for TIMP1 in chemoresistance. In order to gain an enhanced comprehension of the mechanisms underpinning TIMP-1-mediated chemoresistance, we have sought to determine the contribution of CSCs and hypoxia. TIMP-1 plays a role in propagating stemness, although relatively unexplored in the context of CSCs within NSCLC. A second crucial factor in the development of chemoresistance in NSCLC is the interplay between intratumoral hypoxia and CSCs. As the tumor grows, metabolic demand for oxygen increases and hypoxic regions are seen in areas furthest from the blood vessels. We have shown TIMP1 levels to increase under experimentally-induced hypoxia. In the present study, we cultured NSCLC cell lines and their TIMP1 KD clones in an assay with serum-free media and found a significant decrease in spheroid size in TIMP1 KD clones. Postulating a reduction in CSC population in KD clones, we determined the NSCLC CSC markers CD133 and ALDH’s expression in the NT and KD TIMP1 clones. Flow cytometry results showed that CD133pos and ALDHhigh populations were significantly decreased in TIMP1 KD clones relative to NT clones. Moreover, KD clone of TIMP1 showed a decrease in the levels of CSC-specific Transcription factors Oct 4A and Nanog. Taken together, our findings confirm that reduction in TIMP1 expression negatively impacts CSC populations. Furthermore, we determined the mRNA levels of CD44, another CSC marker also expressed in lung cancer is upregulated under hypoxia (1% O2) in both the NT and KD clones of TIMP1. Thus, we postulate that TIMP1 enhances chemoresistance by promoting CSC propagation within a hypoxic tumor microenvironment. Citation Format: Ilamathi Thirusenthilarasan, Wei Xiao, Mumtaz V. Rojiani. The significance of TIMP-1 and hypoxia in cancer stemness: A synergistic role in chemoresistance [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 2779.

Abstract 5658: Genome-scale CRISPR screen in 3D tumor models identifies EGFR-TKI resistance mechanisms in human NSCLC

Abstract INTRODUCTION: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the primary treatment for EGFR-mutated non-small-cell lung cancer (NSCLC). Despite Osimertinib, an FDA-approved EGFR-TKI, showing high selectivity for EGFR-activating mutations, resistance inevitably arises, leading to disease progression. The influence of genes within cancer on Osimertinib response remains unclear. To tackle this challenge, CRISPR screens have been extensively used. However, current CRISPR screens investigating EGFR TKI resistance heavily rely on 2D monolayer cell models, lacking the ability to replicate in vivo tumors accurately. In response, we conducted a genome-scale loss-of-function CRISPR screening employing 3D tumor models embedded in an extracellular matrix across various NSCLC cell lines. Utilizing a comprehensive panel of CRISPR screens in both 3D tumor models and 2D monolayer models, we systematically assessed how genetic alterations impact cell resistance and transformation against treatment with Osimertinib, in diverse cellular contexts. METHOD: Genome-scale CRISPR-Cas9 screens in 10 NSCLC cell lines used 3D tumor models and 2D cells to pinpoint genes pivotal for EGFR TKI resistance. Cas9-expressing cell lines were transduced with a lentivirus carrying 60,000 sgRNAs targeting ~20,000 human genes. Cells were cultured in both models and treated with optimized Osimertinib or DMSO, inducing 20-30% cell growth inhibition for 3 days. Post-treatment, cells were recovered for 4 days. This treatment cycle was repeated 3-4 times in 3D models and 2-3 times in 2D cells. The sgRNA composition in each pool was analyzed using Next Generation Sequencing after treatment cycles in both models. RESULTS: Upon analyzing CRISPR screening data across 10 distinct cell lines to assess drug phenotypes, we confirmed the enrichment of established resistance pathways like PI3K/AKT/mTOR, Hippo, and MAPK signaling pathways in both 2D monolayer cells and 3D tumor models. However, notable discrepancies in EGFR TKI resistance mechanisms were evident between these two models. Specifically, CRISPR screens conducted with 3D tumor models unveiled unique resistance mechanisms, notably the LKB1/AMPK/mTOR pathway (STK11, GSK3B), Ubiquitination (RNF7, ARIH2), and stabilization of E-cadherin adherens junction (NCKAP1, EXOC4) differing from those identified in conventional 2D monolayer model. Furthermore, the 3D tumor models exhibited significantly heightened enrichment of the MAPK and Hippo signaling pathways compared to their drug phenotype score in 2D monolayer cells. CONCLUSION: This study underscores the significance of employing the 3D tumor model in drug phenotype CRISPR screen. This approach recapitulates unique gene dependency patterns and interactions linked to EGFR-TKI resistance in a 3D tumor context, revealing potential targetable vulnerabilities context-dependent. Citation Format: Pranay Agarwal, Soon Youn Choi, Xin Liu, Jina Song, Maya Tureez, Aashka Mehta, Un Jae Baek, Kyuho Han, Hong-Pyo Lee. Genome-scale CRISPR screen in 3D tumor models identifies EGFR-TKI resistance mechanisms in human NSCLC [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 5658.

Abstract 5907: Pre-clinical evaluation of a novel antibody drug conjugate (ADC) LM-317 targeting NaPi2b

Abstract Introduction: NaPi2b is a multi-transmembrane type II sodium-dependent phosphate transporters that regulates phosphate homeostasis in normal physiological condition [1]. It is highly expressed in ovarian cancer (OC), non-small-cell lung cancer (NSCLC), and papillary thyroid cancer, with limited expression in normal tissue, making it a promising target for antibody-drug conjugates (ADCs) [2,3]. LM-317 is a novel NaPi2b targeted humanized monoclonal antibody LM-117 conjugated to the next-generation topoisomerase I inhibitor LDX2 via a cleavable linker, with antibody-drug ratio of 8. Here, we present the preclinical in vivo and in vitro results of LM-317. Results: LM-317 is highly specific cross-reactive with rhesus monkeys, cynomolgus monkeys, mouse, and rat NaPi2b. Concentration-dependent cell binding and internalization effects of LM-317 were observed in human NaPi2b-expressing cells, and OC and NSCLC cells expressing NaPi2b, with EC-50 of 0.92 - 9.7 nM and 1.51 - 4.76 nM, respectively. The cytotoxicity effect of LM-317 in NaPi2b -positive tumor cells was superior to LM-117-DXD, with IC-50 of 0.002 - 0.52nM. The in vivo studies showed that 1 mg/kg of LM-317 almost completely eradicated tumors in the OVCAR-3 xenograft mice model of OC, and similar antitumor activity was observed in the NCI-H175-xenograft mice model of NSCLC at the dose of 3 mg/kg. Single dose of 6 mg/kg of LM-317 showed sustained tumor eradication in the NSCLC xenograft -mouse model. LM-317 also exhibited potent tumor regression in the PDX model of OC and NSCLC. The tumor growth inhibition (TGI) value was 80%-100% in OC and NSCLC PDX models with different expression degree of NaPi2b after treatment with LM-317. The antitumor activity of LM-317 in cell line- and PDX models of OC and NSLCL was comparable to those of LM-117-DXD. Conclusion: The novel ADC LM-317 targeting NaPi2b showed robust antitumor activity in vitro, and in the OC and NSCLC cell line derived models and PDX models. LM-317 could potentially provide therapeutic benefit to treat NaPi2b-positive tumors including OC and NSCLC in the future. Reference: 1.S. Banerjee et al. Cancer Treatment Reviews 112 (2023) 1024892.Finstad CL, Lloyd KO, Federici MG, et al. Clin. Cancer Res. 1997;3(8):1433-14423.Zhang et al. Tumor Biology July 2017: 1-7. Citation Format: Wentao Huang, Zhifang Liu, Yifan Li, Heng Pan, Xia Qin, Da Fei, Runsheng Li. Pre-clinical evaluation of a novel antibody drug conjugate (ADC) LM-317 targeting NaPi2b [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 5907.

Abstract 1935: The FAK/SRC axis mediates resistance to KRAS G12C inhibitors and its blockade can overcome KRAS inhibitor resistance

Abstract Activating mutations in KRAS are found in approximately 30% of non-small cell lung cancer (NSCLC), and among all KRAS mutations, KRAS G12C is the most frequent variant in NSCLC, with a prevalence of approximately 14%. KRAS G12C inhibitors, sotorasib and adagrasib are FDA approved for locally advanced or metastatic KRAS G12C-positive NSCLC. However, clinical evidence suggests that there are various factors limiting the efficacy of KRAS G12C inhibitors in patients with KRAS G12C-positive NSCLC, highlighting the urgent need for novel treatment strategies or combinations to improve efficacy. Therefore, we sought to identify effective combinations to enhance the efficacy of KRAS G12C inhibitors using in vitro and in vivo models of KRAS G12C-positive NSCLC. Employing a high throughput in vitro drug screening effort using KRAS mutant NSCLC cell lines, we observed that Focal Adhesion Kinase (FAK) and Steroid Receptor Coactivator (SRC) inhibitors produced a synergistic effect when combined with KRAS G12C inhibitors adagrasib or sotorasib. As determined by reverse phase array and Western blotting, in H358, H23, HCC44, and H2122 cells, KRAS inhibitor treatment alone resulted in an initial suppression of RAS/MAPK and AKT pathway activation which was followed by upregulation of multiple receptor tyrosine kinases and integrins which contributed to the re-activation of the RAS/MAPK and AKT pathways after 24-48 hours. We identified FAK as a key downstream mediator of these bypass pathways. FAK/SRC inhibitors enhanced the efficacy of KRAS G12C inhibitors by preventing this feedback activation. Moreover, we observed increased FAK activation in H358 NSCLC cell lines with acquired resistance to adagrasib or sotorasib as compared to parental cells, and FAK/SRC inhibitors re-sensitized resistant cells to KRAS G12C inhibitors. Using a xenograft model of human KRAS mutant NSCLC, we determined that the combination of repotrectinib, a FAK/SRC inhibitor, and a KRAS G12C inhibitor significantly suppressed tumor growth as compared to KRAS G12C inhibitors alone, and this combination was well tolerated. Overall, our findings indicate that activation of FAK is a key mechanism of adaptive feedback and acquired resistance to KRAS G12C inhibitors in KRAS G12C-positive NSCLC and highlight the therapeutic potential of FAK/SRC inhibitors in combination with KRAS G12C inhibitors. These data support the clinical testing of the combination of FAK/SRC inhibitors and KRAS G12C inhibitors in patients with KRAS G12C-positive NSCLC. Citation Format: Yuji Shibata, Hibiki Udagawa, Monique B. Nilsson, Jacqulyne Robichaux, Ana Galan-Cobo, Marcelo Negrao, David P. Molkentine, Junqin He, Alissa Poteete, Yu Qian, Qian Huang, Ferdinandos Skoulidis, John V. Heymach. The FAK/SRC axis mediates resistance to KRAS G12C inhibitors and its blockade can overcome KRAS inhibitor resistance [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 1935.

Abstract 4266: Evaluation of integrin alpha v beta 5 as a novel target for non-small cell lung cancer via tumor intrinsic and host immune regulation

Abstract Lung cancer is the leading cause of cancer related deaths worldwide, with the most prevalent subtype being non-small cell lung cancer (NSCLC). As only a subset of patients exhibits durable clinical responses to current treatments, including targeted therapy and immunotherapy, new treatment options are needed. Integrins (ITGs) are a diverse class of heterodimeric, transmembrane receptors that bind extracellularly to the extracellular matrix (ECM) and intracellularly to the cytoskeleton to integrate signals bi-directionally between the extracellular environment and cell interior. One of 18 α subunits is paired with one of 6 β subunits to create the 24 known αβ ITGs in mammals. ITGs are expressed at low levels in normal tissue and can be upregulated in cancer cells in response to stress signals in the tumor microenvironment (TME). Altered expression of ITGs is associated with enhanced cell proliferation, metastasis, and immune evasion. Targeting of the diverse ITG family members by inhibitors not specific to individual isoforms has obscured understanding of potentially distinct functions of each heterodimer. Through data mining of a genome wide CRISPR screening publicly available at the DepMap portal, we have identified a novel cancer dependency to ITG αvβ5 in approximately 40% of NSCLC cell lines. Using small molecule ITG αv inhibitors, we have mirrored sensitivity of NSCLC cell lines to their ITG αvβ5 CRISPR scores, suggesting that these inhibitors function specifically through ITG αvβ5 in cell lines. RNA sequencing analysis following αvβ5 inhibition in human NSCLC cell lines revealed downregulation of YAP and E2F1 target genes with alterations in gene ontologies associated with cell cycling and cell death in sensitive, but not resistant, lines. This is consistent with the known function of YAP driving gene transcription promoting cell proliferation and survival, and of E2F1 being implicated in regulating the proliferation and self-renewal of cancer stem cell (CSC). Additional changes to immune processes, specifically perturbations to interferon (IFN) pathways, were identified in response to ITG αvβ5 inhibition, suggesting that ITG αvβ5 may play a role in host anti-tumor immune responses. Pharmacological inhibition of ITG αvβ5 also led to a reduction of tumor growth in NSCLC murine models accompanied with increased CD8 T cell activation. These findings support ITG αvβ5 as a unique target of cancer dependency in NSCLC whose inhibition promotes anti-tumor responses through both tumor intrinsic and host immune regulatory mechanisms. Citation Format: Bitta P. Kahangi, William P. Crosson, Ji-Ann Lee, Camelia Dumitras, Tianhao Zhang, Ramin Salehi-Rad, Linh M. Tran, Michael Palazzolo, Dylan Conklin, Steven M. Dubinett, Bin Liu. Evaluation of integrin alpha v beta 5 as a novel target for non-small cell lung cancer via tumor intrinsic and host immune regulation [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 4266.

Abstract 1976: Targeting metabolism in non-small cell lung cancer (NSCLC) with the novel multitarget small molecule PI3K-CDK4/6-CDK9 inhibitor LCI139

Abstract Introduction: NSCLC is a heterogenous disease estimated to cause the majority of all 2023 United States cancer-related deaths. There is no broadly applicable targeted therapy to treat lung cancer and those FDA-approved drugs target patient-specific biomarker mutations such as EGFR, ALK, ROS1, etc. Targeting multiple oncogenic pathways to induce synthetic lethality is an attractive strategy for anticancer therapeutic development. Here, we describe the effects of novel multitarget small molecule PI3K-CDK4/6-CDK9 inhibitor LCI139 on a panel of human NSCLC cells of mixed histologic and mutational backgrounds. Methods: LCI139 specific target inhibition was assessed by cell-free kinase hotspot/lipid kinase assay and KINOMEscan. LCI139 (0.001-10μM) was screened against NCI-H1975, NCI-H1703, NCI-H1373, NCI-H1781 and NCI-H226 human cell lines; IC50 values determined by CellTiter-Glo/WST-8 Assay and apoptotic rate by flow cytometry (Annexin V/7-AAD). Metabolomic profile of representative LCI139 sensitive (LCI139S) and resistant (LCI139R) NSCLC cells was evaluated by western blot. Results: LCI139 is a highly potent inhibitor of PI3K-CDK4/6-CDK9: 0.070µM (PI3Kα), 0.461µM (PI3Kγ), 0.214µM (PI3Kδ), 0.0015µM (CDK4), 0.0036µM (CDK6), 0.000039µM (CDK9). NCI-H1703, NCI-H226, NCI-H1373 and NCI-H1975 were highly sensitive to LCI139 (0.68, 3.2, 35.27 and 342.4nM IC50), while NCI-H1781 remained insensitive up to 10μM. Confirming those findings, LCI139 promoted robust apoptotic cell death in NCI-H1703, NCI-H226, NCI-H1373 and NCI-H1975 but not NCI-H1781. LCI139S H1703 cells displayed increased bioenergetic reliance on oxidative phosphorylation (OXPHOS), compared with the LCI139R H1781 cells. In the LCI139S H1703 cells, LCI139 treatment decreased expression of all mitochondrial complexes (I-IV) and glycolytic enzymes (HK2, GAPDH, LDHA). Conversely, LCI139 treatment of LCI139R H1781 cells only inhibited expression of mitochondrial complexes II and III, but increased glucose uptake (Glut1) and retained expression of other glycolytic enzymes. Conclusions: Triple PI3K-CDK4/6-CDK9 inhibitor LCI139 is nanomolar potent against several NSCLC cells lines of mixed histologic and mutational backgrounds. NSCLC cells that are most reliant on OXPHOS to generate ATP, a classic metabolic adaptation to chemotherapy, appear to be most sensitive to LCI139. Taken together, these data support further drug characterization and mechanistic dissection to assess LCI139’s potential clinical utility in treating advanced stage and recurrent NSCLC. Citation Format: Cody C. McHale, Anna V. Ivanina Foureau, Hailey L. Dryden, Krishnaiah Maddeboina, Dhananjaya Pal, Bharath Yada, Page Mangum Arditti, Fei Guo, Kathryn F. Mileham, David M. Foureau, Donald L. Durden. Targeting metabolism in non-small cell lung cancer (NSCLC) with the novel multitarget small molecule PI3K-CDK4/6-CDK9 inhibitor LCI139 [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 1976.

Abstract 2531: rs822336 as a predictive biomarker for anti-PD-1/PD-L1 immunotherapy in advanced NSCLC: Unraveling molecular mechanisms

Abstract Efficient predictive biomarkers are needed for immune checkpoint inhibitor (ICI)-based immunotherapy in non-small-cell lung cancer (NSCLC). So far, testing the predictive value of single nucleotide polymorphisms (SNPs) in programmed cell death 1 (PD-1) or its ligand 1 (PD-L1) has shown contrasting results. Here, we aimed to validate the predictive value of PD-L1 SNPs in advanced NSCLC patients treated with ICIs as well as to define the molecular mechanisms underlying the role of identified SNP candidate. rs822336 SNP efficiently predicted response to anti-PD-1/PD-L1-based immunotherapy in advanced NSCLC patients as compared to rs2282055 and rs4143815 SNPs. rs822336 SNP mapped on promoter/enhancer region of PD-L1, differentially affecting the induction of PD-L1 expression in human NSCLC cell lines. The induction of PD-L1 expression by rs822336 SNP was predicted by allele-specificity binding of two identified transcription factors: C/EBPβ and NFIC. As a result, silencing of C/EBPβ and NFIC differentially modulated the induction of PD-L1 expression in human NSCLC cell lines carrying different rs822336 genotypes. In addition, binding microarray validated the allele- specificity binding of C/EBPβ and NFIC to PD-L1 promoter/enhancer region based on rs822336 genotype in human NSCLC cell lines. Lastly, the induction of PD-L1 expression by rs822336 genotype differentially affected the susceptibility to anti-PD-1 monoclonal antibody nivolumab of human NSCLC cell lines co-cultured with HLA class I antigen matched PBMC. These results have clinical relevance since identified rs822336 SNP and the induction of PD-L1 expression as novel biomarkers for predicting ICI-based immunotherapy in NSCLC patients. Citation Format: Giovanna Polcaro, Luigi Liguori, Valentina Manzo, Annalisa Chianese, Giuliana Donadio, Alessandro Caputo, Giosuè Scognamiglio, Federica Dell'Annunziata, Maddalena Langella, Graziamaria Corbi, Alessandro Ottaiano, Marco Cascella, Francesco Perri, Margot De Marco, Jessica Dal Col, Valentina Pagliara, Pio Zeppa, Amelia Filippelli, Gianluigi Franci, Fabrizio Dal Piaz, Valeria Conti, Stefano Pepe, Francesco Sabbatino. rs822336 as a predictive biomarker for anti-PD-1/PD-L1 immunotherapy in advanced NSCLC: Unraveling molecular mechanisms [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 2531.

Abstract 2058: Compound library screening to identify modulators of alternative splicing in non-small cell lung cancer (NSCLC)

Abstract Alternative splicing is a molecular mechanism that allows a single gene to encode multiple proteins. It is a complex and highly controlled process used to regulate normal gene expression but is often dysregulated in cancer. Compounds that can modulate alternative splicing are currently being explored as a potential new class of therapeutic agent in cancer. This highlights the need for a deeper understanding of the splicing process, its regulation, and its impact. The discovery of novel and specific tool compounds that modulate splicing would therefore not only be beneficial in investigating the regulation and dysregulation of splicing in cancer but could also be exploited therapeutically. To identify novel regulators of splicing, we generated a cell-based split luciferase screening assay based on alternative splicing of MCL-1 (myeloid cell leukemia-1 protein) pre-mRNA. The MCL1 gene usually produces an mRNA encoding a ‘long’ variant (MCL1L) that is an anti-apoptotic protein often highly expressed in cancers. However, in some circumstances, for example following genetic knockdown of splicing factors, a pro-apoptotic ‘short’ variant (MCL1S) is expressed as a result of exon-skipping. Here we engineered the human NSCLC cell line NCI-H1299 to express a luminescent-tagged version of the MCL1S splice variant to monitor its induction upon spliceosome modulation. Using this engineered cell line, we screened an unannotated library of 12,000 compounds selected to have low molecular weights and favorable properties for cellular uptake. The screen had an average Z’ value of 0.89 over 45 microplates, indicating high assay robustness. Hits were identified as any compound with a luminescence of greater than the average + two standard deviations of the screening dataset. The compounds were validated by repetition in the screening assay, giving 34 candidate hits that were then triaged by qPCR assay to confirm splicing modulation of MCL1. One interesting hit was found to increase mRNA and cellular protein levels of MCL1S and induced altered splicing across the transcriptome that was distinct from the splicing profiles of a diverse panel of splicing modulators, including compounds targeting SF3B1, CLK, and RBM39. In addition, treatment with this hit compound resulted in accumulation of the splicing factor SC35 in cytoplasmic granules, an unusual phenotype not seen with known splicing modulators, that could explain the distinct splicing modulation we have observed. Deconvolution and further characterization of screening hits and potentially unique new mechanisms of action could improve current understanding of alternative splicing and its regulation in NSCLC. The discovery of novel compounds to expand our current toolset of splicing modulators will be key in building the foundation for future splicing targeted drug discovery. Citation Format: Rachel Cooley, Marissa V. Powers, Adam G. Bond, Patrizia Jensen, Gary Newton, Andrea Scarpino, Juliane Braun, Christina Esdar, Paul A. Clarke. Compound library screening to identify modulators of alternative splicing in non-small cell lung cancer (NSCLC) [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 2058.

Abstract 2006: Deciphering the interplay of β-catenin/YAP signaling and alveolar lineage plasticity during targeted therapy in non-small cell lung cancer

Abstract Molecularly targeted therapies have significantly enhanced clinical outcomes by directly addressing oncogenic driver mutations in genes such as EGFR. However, despite the success of treatments targeting these mutations, long-term patient survival remains limited. This study investigates the molecular mechanisms underlying drug-tolerance in response to targeted therapies in non-small cell lung cancer (NSCLC). Using single-cell RNA sequencing of oncogene-driven human NSCLCs at the residual disease (RD) state during active targeted therapy, our investigation reveals an increase of an alveolar type I/II (AT1/2) mixed lineage program in surviving cancer cells, resembling an alveolar cell-like state. We observed increased WNT3A/4 ligands, FZD2 receptors, β-catenin signaling, and AT1/2 signatures at the RD stage. Consistent with clinical results, AT1/2 signatures and target genes of β-catenin and YAP are increased in drug-tolerant persister (DTP) cells in preclinical models. Additionally, we discovered that β-catenin and YAP form a stable nuclear protein complex in DTP cells. Disrupting β-catenin/YAP protein expression and stability in DTP cells by knocking down FZD2 or interrupting the destruction complex of β-catenin/YAP leads to re-sensitization to the EGFR inhibitor Osimertinib, suggesting a potential therapeutic approach. Furthermore, this therapeutic strategy decreased AT1/2 gene signatures. Our results highlight an interdependence between β-catenin and YAP, with both proteins playing crucial roles in sustaining DTP cells and promoting the alveolar cell like lineage plasticity. These findings shed light on the complex interplay between β-catenin/YAP signaling and alveolar signatures in the residual cancer state, offering mechanistic insights and potential therapeutic strategies to address drug tolerance and improve clinical outcomes. Citation Format: Yu-Ting Chou, Wei Wu, Daniel Kerr, Macey Slota, Trever Bivona. Deciphering the interplay of β-catenin/YAP signaling and alveolar lineage plasticity during targeted therapy in non-small cell lung 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 2006.

Abstract 6496: Assessment of tyrosine kinase inhibitor bypass mechanisms in lung cancer using single cell multiomics, patient derived organoids and rationally designed drug screens

Abstract Lung cancer (LC) is the leading cause of cancer-induced mortality, with 350 patients in the US dying from LC daily, the majority from non-small cell lung cancer (NSCLC). Molecular-targeted therapy such as tyrosine kinase inhibitors (TKI) are effective in first and subsequent lines of therapy against oncogenic drivers (KRAS, EGFR, or ALK fusions, others); however, nearly all treated patients progress eventually and run out of therapeutic options. Key reasons are the lack of predictive biomarkers and LC models that reflect the underlying heterogeneity and different phenotypic cell states among subclones within and between patients. Here, we developed a novel platform for refining the resolution of molecular interrogation to the single cell level, using single cell spatial multiomic (scSpMO), coupled with rational designed drug screens in patient-derived organoids (PDOs) from LC biopsies obtained upon progression. By deriving LC PDOs in epithelial and tumor microenvironment (TME) conditions to faithfully maintain the histological and genetic features of their respective LC tissues, we identified enrichment conditions for LC PDOs guided by tumor mutation variants and activated pathways. PDOs are maintained under the same treatment condition in the clinic (e.g., Lorlatinib) and drug testing is tailored to identify next lines of combined therapy. With six patients enrolled and others in ongoing studies, single cell PDOs (at >80% establishment rate) were used to determine key molecular bypass mechanism for resistance to TKI, including on-target variants, driver bypass, lineage plasticity and acquired resistance. Functional assays for acquired resistance such as PI3K/AKT signaling, Src kinase, BRAF fusion and MET hyperactivity allow the identification of potential novel combined lines of therapy for each patient through the compassionate care program and/or trial participation. Our platform when empowered with datasets of bulk, scRNA-seq and scSpMO signatures of primary human NSCLC, together with PDOs offer the ability to perform analysis of LC phenotypes such as lineage transformation in high-content assays, predict and/or act on resistance to therapy and provides a path for precision medicine-guided immediate impact on patient care. Citation Format: Liqiong Liu, Ann Strange, Schuyler Lee, Bifeng Gao, Daniel Merrick, Tejas Patil, James DeGregori, D Ross Camidge, Sharon R. Pine, Hatim E. Sabaawy. Assessment of tyrosine kinase inhibitor bypass mechanisms in lung cancer using single cell multiomics, patient derived organoids and rationally designed drug screens [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 6496.

Abstract 1538: Impact of C-reactive protein on the efficacy of immune checkpoint inhibitors in non-small cell lung cancer

Abstract Background: Immune checkpoint inhibitors (ICIs) therapy has achieved remarkable success in the treatment of non-small cell lung cancer (NSCLC). Clinical studies have suggested a correlation between C-reactive protein (CRP) levels and treatment efficacy, but it remains unclear whether CRP can directly impact the efficacy. Therefore, we investigated the imapct of CRP on the efficacy of ICIs in NSCLC. Methods: The tumor growth model was established in CRP knockout and wildtype mice by injecting LLC cells to evaluate the effect of CRP on tumor proliferation. The frequencies and phenotypes of macrophages and T cells in mouse tumors were detected by flow cytometry. The impact of CRP on macrophage polarization was evaluated using flow cytometry and IF, while its impact on T cell chemokines CCL5, CXCL9, and CXCL10 was analyzed by ELISA and qRT-PCR. mCRP and α-PD-1 were implemented in C57/BL6 mice injected with LLC cells to evaluate the effect of mCRP on tumor immunotherapy. The frequencies of T cells in mouse tumors were detected by flow cytometry. Expression of mCRP and infiltration of immune cells in human NSCLC tissues were analyzed using IHC. Results: We found that tumor progression was enhanced and the proportion of tumor-infiltrated M1 macrophages was decreased in CRP knockout mice. Using human PBMC-derived macrophage and RAW264.7 cell lines, we demonstrated that the monomeric form of CRP, known as mCRP, induced M1 polarization of macrophages, leading to increased secretion of CCL5, CXCL9, and CXCL10. In tumor bearing mice, mCRP treatment enhanced anti-tumor immunity and suppressed tumor progression by increasing CD4+ and CD8+ T cell recruitment. Surprisingly, the combined treatment of mCRP and α-PD-1 induced more significant tumor regression than α-PD-1 treatment alone. Additionally, high level of mCRP in NSCLC tissues is correlated with a more inflamed tumor microenvironment phenotype. Conclusion: mCRP can enhance the efficacy of immune checkpoint inhibitors in NSCLC by activating anti-tumor immunity. Citation Format: Wenyuan Li, Hui Guo. Impact of C-reactive protein on the efficacy of immune checkpoint inhibitors in non-small cell lung 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 1538.

Synthesis and biological evaluation of novel benzothiazole derivatives as potential anticancer and antiinflammatory agents.

Introduction: Cancer, a significant global health concern, necessitates innovative treatments. The pivotal role of chronic inflammation in cancer development underscores the urgency for novel therapeutic strategies. Benzothiazole derivatives exhibit promise due to their distinctive structures and broad spectrum of biological effects. This study aims to explore new anti-tumor small molecule drugs that simultaneously anti-inflammatory and anticancer based on the advantages of benzothiazole frameworks. Methods: The compounds were characterized by nuclear magnetic resonance (NMR), liquid chromatograph-mass spectrometer (LC-MS) and high performance liquid chromatography (HPLC) for structure as well as purity and other related physicochemical properties. The effects of the compounds on the proliferation of human epidermoid carcinoma cell line (A431) and human non-small cell lung cancer cell lines (A549, H1299) were evaluated by MTT method. The effect of compounds on the expression levels of inflammatory factors IL-6 and TNF-α in mouse monocyte macrophages (RAW264.7) was assessed using enzyme-linked immunosorbent assay (ELISA). The effect of compounds on apoptosis and cell cycle of A431 and A549 cells was evaluated by flow cytometry. The effect of compounds on A431 and A549 cell migration was evaluated by scratch wound healing assay. The effect of compounds on protein expression levels in A431 and A549 cells was assessed by Western Blot assay. The physicochemical parameters, pharmacokinetic properties, toxicity and drug similarity of the active compound were predicted using Swiss ADME and admetSAR web servers. Results: Twenty-five novel benzothiazole compounds were designed and synthesized, with their structures confirmed through spectrogram verification. The active compound 6-chloro-N-(4-nitrobenzyl) benzo[d] thiazol-2-amine (compound B7) was screened through a series of bioactivity assessments, which significantly inhibited the proliferation of A431, A549 and H1299 cancer cells, decreased the activity of IL-6 and TNF-α, and hindered cell migration. In addition, at concentrations of 1, 2, and 4μM, B7 exhibited apoptosis-promoting and cell cycle-arresting effects similar to those of the lead compound 7-chloro-N-(2, 6-dichlorophenyl) benzo[d] thiazole-2-amine (compound 4i). Western blot analysis confirmed that B7 inhibited both AKT and ERK signaling pathways in A431 and A549 cells. The prediction results of ADMET indicated that B7 had good drug properties. Discussion: This study has innovatively developed a series of benzothiazole derivatives, with a focus on compound B7 due to its notable dual anticancer and anti-inflammatory activities. B7 stands out for its ability to significantly reduce cancer cell proliferation in A431, A549, and H1299 cell lines and lower the levels of inflammatory cytokines IL-6 and TNF-α. These results position B7B7 as a promising candidate for dual-action cancer therapy. The study's mechanistic exploration, highlighting B7's simultaneous inhibition of the AKT and ERK pathways, offers a novel strategy for addressing both the survival mechanisms of tumor cells and the inflammatory milieu facilitating cancer progression.

Cytotoxicity and Multi-Enzyme Inhibition of Nepenthes miranda Stem Extract on H838 Human Non-Small Cell Lung Cancer Cells and RPA32, Elastase, Tyrosinase, and Hyaluronidase Proteins

The carnivorous pitcher plants of the genus Nepenthes have long been known for their ethnobotanical applications. In this study, we prepared various extracts from the pitcher, stem, and leaf of Nepenthes miranda using 100% ethanol and assessed their inhibitory effects on key enzymes related to skin aging, including elastase, tyrosinase, and hyaluronidase. The cytotoxicity of the stem extract of N. miranda on H838 human lung carcinoma cells were also characterized by effects on cell survival, migration, proliferation, apoptosis induction, and DNA damage. The cytotoxic efficacy of the extract was enhanced when combined with the chemotherapeutic agent 5-fluorouracil (5-FU), indicating a synergistic effect. Flow cytometry analysis suggested that the stem extract might suppress H838 cell proliferation by inducing G2 cell cycle arrest, thereby inhibiting carcinoma cell proliferation. Gas chromatography–mass spectrometry (GC–MS) enabled the tentative identification of the 15 most abundant compounds in the stem extract of N. miranda. Notably, the extract showed a potent inhibition of the human RPA32 protein (huRPA32), critical for DNA replication, suggesting a novel mechanism for its anticancer action. Molecular docking studies further substantiated the interaction between the extract and huRPA32, highlighting bioactive compounds, especially the two most abundant constituents, stigmast-5-en-3-ol and plumbagin, as potential inhibitors of huRPA32’s DNA-binding activity, offering promising avenues for cancer therapy. Overall, our findings position the stem extract of N. miranda as a promising source of natural compounds for anticancer therapeutics and anti-skin-aging treatments, warranting further investigation into its molecular mechanisms and potential clinical applications.

Signal Transducer and Activator of Transcription 4-Induced Up-Regulated LINC01278 Enhances Proliferation and Invasion of Non-Small Cell Lung Cancer Cells via the MicroRNA-877-5p/Activating Transcription Factor 4 Axis.

The purpose of this study was to investigate the specific effects of signal transducer and activator of transcription 4 (STAT4)-induced long intergenic nonprotein coding RNA 1278 (LINC01278) on the growth of non-small cell lung cancer (NSCLC) cells involved in the microRNA (miR)-877-5p/activated transcription factor 4 (ATF4) axis. NSCLC tumor tissue and adjacent normal tissue were collected. Human normal lung epithelial cell BEAS-2B and human NSCLC cell lines (H1299, H1975, A549, H2228) were collected. The expression levels of STAT4, LINC01278, miR-877-5p, and ATF4 were detected. A549 cells were screened for subsequent experiments. The proliferation ability of cells was detected by colony formation experiment. Cell apoptosis was tested by flow cytometry. Scratch test and transwell assay were used to detect the migration and invasion ability of cells. Biological function of LINC01278 in NSCLC was confirmed by xenograft experiments. Low expression miR-877-5p and high expression of STAT4, LINC01278 and ATF4 were detected in NSCLC. Silenced LINC01278 in A549 cell depressed cell proliferation, migration and invasion, but facilitated cell apoptosis. LINC01278 was positively correlated with STAT4 and could directly bind to miR-877-5p. Upregulating miR-877-5p suppressed NSCLC cell progression, while downregulating miR-877-5p had the opposite effect. Upregulating miR-877-5p abrogated the effects of silenced LINC01278 on NSCLC cell progression. MiR-877-5p targeted ATF4. ATF4 upregulation could partly restore the carcinogenic effect of LINC01278 in vitro and in vivo. Our data supports that STAT4-induced upregulation of LINC01278 promotes NSCLC progression by modulating the miR-877-5p/ATF4 axis, suggesting a novel direction for NSCLC treatment.

Cytotoxicity evaluation of sub-10-nm silver colloid prepared by electrolytic synthesis procedure

Silver nanoparticles with smaller scales tend to exhibit higher cytotoxicity. In the present work, a mild electrolytic synthesis procedure is proposed and implemented for the preparation of sub-10-nm silver colloids in polarity organic solvent media by using the nonionic polymer as a stabilizer. The synthesized silver nanoparticles can be stably dispersed in salt, acid, and alkali dispersion media. The cell viability and cytotoxicity are investigated by fluorescein diacetate/propidium iodide double staining and thiazolium blue colorimetry in vitro. Under concentration-gradient and time-gradient tests, the synthesized silver nanoparticles exhibit significant cytotoxicity against the human hepatocellular carcinoma cells of HepG2 and the human non-small cell lung cancer cells of A549 at the exposure dose of 1.6 and 2.0 ug mL−1, respectively.

Editorial Expression of Concern: MicroRNA signatures of TRAIL resistance in human non-small cell lung cancer.

Editorial Expression of Concern: MicroRNA signatures of TRAIL resistance in human non-small cell lung cancer.

Elevated expression of complement factor I in lung cancer cells associates with shorter survival–Potentially via non-canonical mechanism

While numerous membrane-bound complement inhibitors protect the body's cells from innate immunity's autoaggression, soluble inhibitors like complement factor I (FI) are rarely produced outside the liver. Previously, we reported the expression of FI in non-small cell lung cancer (NSCLC) cell lines. Now, we assessed the content of FI in cancer biopsies from lung cancer patients and associated the results with clinicopathological characteristics and clinical outcomes. Immunohistochemical staining intensity did not correlate with age, smoking status, tumor size, stage, differentiation grade, and T cell infiltrates, but was associated with progression-free survival (PFS), overall survival (OS) and disease-specific survival (DSS). Multivariate Cox analysis of low vs. high FI content revealed HR 0.55, 95 % CI 0.32-0.95, p=0.031 for PFS, HR 0.51, 95 % CI 0.25-1.02, p=0.055 for OS, and HR 0.32, 95 % CI 0.12-0.84, p=0.021 for DSS. Unfavorable prognosis might stem from the non-canonical role of FI, as the staining pattern did not correlate with C4d - the product of FI-supported degradation of active complement component C4b. To elucidate that, we engineered three human NSCLC cell lines naturally expressing FI with CRISPR/Cas9 technology, and compared the transcriptome of FI-deficient and FI-sufficient clones in each cell line. RNA sequencing revealed differentially expressed genes engaged in intracellular signaling pathways controlling proliferation, apoptosis, and responsiveness to growth factors. Moreover, in vitro colony-formation assays showed that FI-deficient cells formed smaller foci than FI-sufficient NSCLC cells, but their size increased when purified FI protein was added to the medium. We postulate that a non-canonical activity of FI influences cellular physiology and contributes to the poor prognosis of lung cancer patients.

Boric Acid Affects the Expression of DNA Double-Strand Break Repair Factors in A549 Cells and A549 Cancer Stem Cells: An In Vitro Study

DNA double-strand break (DSB) repair genes interact with tumor stemness- and resistance-associated processes in cancer stem cells (CSCs). Therefore, targeting DNA DSB genes in cancer treatment is important for the CSC phenotype. Although the anti-cancer effect of boric acid (BA) has been studied, its effect on DNA DSB is unclear. Moreover, no studies investigate BA’s effects on DNA DSB of lung cancer stem cells (LC-SCs). To fill the gap, we aimed to assess the effects of BA on A549 cancer stem cells. CSCs were isolated from human non-small cell lung cancer cells (A549) and characterized by flow cytometry. Different concentrations of BA (at doses ranging from 1 to 100 mM) were applied to cancer stem cells. Cytotoxic activities were determined using the cell viability assay (MTT assay) at 24 and 48 h. Expression levels of DNA DSB genes that BRCA1, BRCA2, RAD51, KU70/80, ATM, and XRCC4 were evaluated by RT-qPCR. Additionally, immunofluorescence staining analysis was exploited for caspase-3 and E-cadherin. ATM expression increased significantly (p < 0.001). No significant change was observed in the expression of other genes. Moreover, BA up-regulated caspase-3 and E-cadherin expression. Consequently, we can say that BA affects DNA DSB and the apoptotic abilities of LC-SCs.Graphical

Preparation and characterization of aspirin–fucoidan complex and its admirable antitumor activity on human non-small cell lung cancer cells

The purpose of this work is to prepare a novel acetylated derivative of Undaria pinnatifida fucoidan (UPFUC) with admirable antitumor activity. Fucoidan was first acetylated by acetylsalicylic acid (aspirin, ASA) to form the ASA-UPFUC complex. The antitumor efficacy results stated that ASA-UPFUC inhibited the proliferation of human non-small cell lung cancer A549 cells in a dose-dependent manner, with an IC50 value of 49.09 μg/mL, 50.20 % lower than that of UPFUC. Importantly, the acetylation process had no adverse effects on the backbone structure of UPFUC. Simultaneously, ASA-UPFUC demonstrated a larger charge density than UPFUC, leading to enhanced solubility, improved surface charge effects, and a greater potential for exerting biological activity. Consequently, ASA-UPFUC increased the formation of alkyl and hydrogen bonds with tumor necrosis factor related apoptosis-inducing ligand receptors DR4 and DR5, thereby effectively stimulating the generation of cellular reactive oxygen species, diminishing mitochondrial membrane potential, suppressing nuclear factor κB (NFκB) p65 phosphorylation, enhancing the contents of Bax and cleaved caspase 3, and reducing the level of Bcl-2. The collective effects ultimately triggered the mitochondrial apoptotic pathway, leading to apoptosis in A549 cells. The findings support the potential utilization of ASA-UPFUC as a novel dietary additive for human lung cancer chemoprevention.

Activity-Based Nitric Oxide-Responsive Porphyrin for Site-Selective and Nascent Cancer Ablation.

Nitric oxide (NO) generated within the tumor microenvironment is an established driver of cancer progression and metastasis. Recent efforts have focused on leveraging this feature to target cancer through the development of diagnostic imaging agents and activatable chemotherapeutics. In this context, porphyrins represent an extraordinarily promising class of molecules, owing to their demonstrated use within both modalities. However, the remodeling of a standard porphyrin to afford a responsive chemical that can distinguish elevated NO from physiological levels has remained a significant research challenge. In this study, we employed a photoinduced electron transfer strategy to develop a panel of NO-activatable porphyrin photosensitizers (NOxPorfins) augmented with real-time fluorescence monitoring capabilities. The lead compound, NOxPorfin-1, features an o-phenylenediamine trigger that can effectively capture NO (via N2O3) to yield a triazole product that exhibits a 7.5-fold enhancement and a 70-fold turn-on response in the singlet oxygen quantum yield and fluorescence signal, respectively. Beyond demonstrating excellent in vitro responsiveness and selectivity toward NO, we showcase the potent photodynamic therapy (PDT) effect of NOxPorfin-1 in murine breast cancer and human non-small cellular lung cancer cells. Further, to highlight the in vivo efficacy, two key studies were executed. First, we utilized NOxPorfin-1 to ablate murine breast tumors in a site-selective manner without causing substantial collateral damage to healthy tissue. Second, we established a nascent human lung cancer model to demonstrate the unprecedented ability of NOxPorfin-1 to halt tumor growth and progression completely. The results of the latter study have tremendous implications for applying PDT to target metastatic lesions.