Non-small Cell Lung Carcinoma Tumors Research Articles

Extracellular vesicles in non-small cell lung cancer stemness and clinical applications.

Non-small cell lung carcinoma (NSCLC) accounts for 85% of lung cancers, the leading cause of cancer associated deaths in the US and worldwide. Within NSCLC tumors, there is a subpopulation of cancer cells termed cancer stem cells (CSCs) which exhibit stem-like properties that drive NSCLC progression, metastasis, relapse, and therapeutic resistance. Extracellular vesicles (EVs) are membrane-bound nanoparticles secreted by cells that carry vital messages for short- and long-range intercellular communication. Numerous studies have implicated NSCLC CSC-derived EVs in the factors associated with NSCLC lethality. In this review, we have discussed mechanisms of EV-directed cross-talk between CSCs and cells of the tumor microenvironment that promote stemness, tumor progression and metastasis in NSCLC. The mechanistic studies discussed herein have provided insights for developing novel NSCLC diagnostic and prognostic biomarkers and strategies to therapeutically target the NSCLC CSC niche.

Radiation-induced effects on TGF-β and PDGF receptor signaling in cancer-associated fibroblasts.

Cancer-associated fibroblasts (CAFs) consist of heterogeneous connective tissue cells and are often constituting the most abundant cell type in the tumor stroma. Radiation effects on tumor stromal components like CAFs in the context of radiation treatment is not well-described. This study explores potential changes induced by ionizing radiation (IR) on platelet-derived growth factor (PDGF)/PDGFRs and transforming growth factor-beta (TGF-β)/TGFβRs signaling systems in CAFs. Experiments were carried out by employing primary cultures of human CAFs isolated from freshly resected non-small cell lung carcinoma tumor tissues. CAF cultures from nine donors were treated with one high (1 × 18 Gy) or three fractionated (3 × 6 Gy) radiation doses. Alterations in expression levels of TGFβRII and PDGFRα/β induced by IR were analyzed by western blots and flow cytometry. In the presence or absence of cognate ligands, receptor activation was studied in nonirradiated and irradiated CAFs. Radiation exposure did not exert changes in expression of PDGF or TGF-β receptors in CAFs. Additionally, IR alone was unable to trigger activation of either receptor. The radiation regimens tested did not affect PDGFRβ signaling in the presence of PDGF-BB. In contrast, signaling via pSmad2/3 and pSmad1/5/8 appeared to be down-regulated in irradiated CAFs after stimulation with TGF-β, as compared with controls. Our data demonstrate that IR by itself is insufficient to induce measurable changes in PDGF or TGF-β receptor expression levels or to induce receptor activation in CAFs. However, in the presence of their respective ligands, exposure to radiation at certain doses appear to interfere with TGF-β receptor signaling.

The Role of Hematopoietic Stem Cells in Lung Cancer Response to Radiation Therapy

Non-small cell lung carcinoma (NSCLC) comprises approximately 85% of all lung cancer cases in the United States. We demonstrated that after radiation therapy (RT), bone marrow-derived hematopoietic stem and progenitor cells (HSPCs) are recruited to the NSCLC tumor microenvironment (TME). These HSPCs seemed to positively affect tumor regrowth as their numbers directly correlated with regrowth rates. The TME is comprised of tumor tissue, stromal cells, immune cells, bone marrow-derived cells, and extra cellular matrix (ECM) proteins and has emerged as one of the predominant defensive weapons with which cancer can resist various forms of therapeutic intervention. The ability of tumor-associated HSPCs to maintain hematopoietic potency in tumors suggested a prominent role of these cells in tumor physiology, however; what was missing was a mechanistic understanding of: 1) how HSPCs participate in tumor growth post-RT and 2) how HSPCs are maintained within tumors. To answer these questions, we established NSCLC tumors in mice using Lewis Lung Carcinoma (LLC) cells and assessed tumor-associated HSPCs activity and molecular changes in the TME following RT. We observed that RT induces the TME to produce colony stimulating factor (CSF)-1, a factor that promotes the differentiation of HSPCs into tumor supportive M2-macrophages. Adoptive transplantation of dsRed labeled HSPCs into tumor bearing mice followed by RT directly showed the differentiation of HSPCs into M2-macrophages and a concomitant increase in the regrowth of tumors post-RT. Use of a therapeutic inhibitor of the CSF-1 receptor (GW2580) prevented HSPC differentiation in to M2-macrophages and significantly decreasing regrowth rates. We next assessed how tumor-associated HSPCs maintain their hematopoietic potency within the TME. Analysis of tumors demonstrated high expression levels of the laminin 5-1-1 isoform, which is known to bind CD49f (integrin alpha 6), a marker of functional HSPCs. Tumors exposed to RT demonstrated significantly reduced expression of both laminin 5-1-1 and CD49f. When bound, CD49f inhibits phosphorylation of focal adhesion kinase (FAK) resulting in maintenance of pluripotent stem cells. Analysis of tumor-associated HSPCs demonstrated significantly higher levels of phosphorylated FAK following tumor exposure to RT. Since RT induces HSPC differentiation in to M2-macophages, this observation suggests that tumor-associated HSPC functionality is maintained through the interaction between laminin 5-1-1- and CD49f. The identification of single HSPCs that differentiated in to M2-macrophages and which expressed phosphorylated FAK supports this conclusion. Taken together, this data province's evidence of a mechanism wherein RT disrupts laminin 5-1-1/CD49f interactions releasing tumor-associated HSPCs from maintenance signals. Concomitantly, RT induces the production of CSF-1 within the TME, which induces these “released” HSPCs to differentiate into tumor supportive M2-macrophages and promote tumor regrowth post-RT. Overall, these studies define a new understanding of tumor biology in which HSPCs are significant mediators of tumor response to RT. These findings also identify new cellular and molecular pathways to target in the treatment of NSCLC to achieve more optimal clinical outcomes.

P10.08.B PI3K INHIBITION FOR SENSITIZING CANCER CELLS TO TUMOR TREATING FIELDS (TTFIELDS)

Abstract BACKGROUND Tumor Treating Fields (TTFields) are electric fields that disrupt cellular processes critical for cancer cell viability and tumor progression, ultimately leading to cell death. TTFields therapy is approved for treatment of adult patients with glioblastoma (GBM) or unresectable pleural mesothelioma. Clinical trials are underway in other solid tumors, including ovarian cancer and non-small cell lung carcinoma (NSCLC). The objective of this study is to identify possible mechanisms involved in reduced sensitivity of cancer cell to TTFields, and explore strategies to circumvent them. MATERIAL AND METHODS GBM U-87 MG, ovarian cancer A2780, and NSCLC H1299 cells were treated with continuous long-term application of TTFields (1.7 V/cm RMS, 200 or 150 kHz, 6 or 13 days, specific conditions depending on cell line). Changes in signaling pathways were examined for cells following 3 days of treatment with Luminex multiplex assay, followed by Western blot validation for specific pathway markers. In vivo validation was performed in ovarian cancer (MOSE-L), hepatocellular carcinoma (N1-S1), and NSCLC (LL/2) tumor sections from animals treated with TTFields utilizing immunohistochemistry. Next, efficacy of TTFields concomitant with relevant inhibitors was evaluated in vitro and in mice inoculated orthotopically with ovarian cancer cells (MOSE-L). Tumor volume was measured at study end by luciferin signal detection using the In Vivo Imaging System (IVIS). RESULTS TTFields inflicted a cytotoxic effect on the cancer cells that increased over time, though with moderately reduced sensitivity following prolonged treatment application. PI3K/AKT signaling pathway was shown to be activated in treated cells, with the amplitude of AKT phosphorylation increasing over time. AKT phosphorylation was also demonstrated in tumor sections of animals treated with TTFields. Experiments performed with concomitant PI3K/AKT pathway inhibitors sensitized the cells to TTFields, enhancing cytotoxicity in vitro and treatment efficacy in vivo. CONCLUSION PI3K/AKT signaling pathway is involved in cancer cell reduced sensitivity to TTFields, and inhibition of this pathway sensitizes cancer cells to TTFields.

Abstract 1088: Acquired radiation resistance induces thiol-dependent cisplatin cross-resistance

Abstract Purpose. Resistance to radiation, both intrinsic and acquired, remains a significant clinical challenge. It is therefore import to identify the underlying molecular and cellular features involved in this resistance. Materials and Methods. We generated genetically-matched counterparts of various degrees of radiation sensitivity in non-small cell lung carcinoma (NSCLC) tumor models to define characteristics of acquired resistance through repeated exposures to conventional X-ray radiation. Results. As assessed by cell viability and clonogenic assays murine Lewis lung carcinoma (LLC) and human A549 cell lines acquired an approximate 1.5 - 2-fold increase in radiation resistance (RR) as compared to its parental counterpart. Morphologically, we found that A549-RR exhibited a greater nucleus-to-cytosol (N/C) ratio as compared to its respective counterpart. Since the N/C ratio has been linked to the differentiation state, we next investigated the epithelial-to-mesenchymal transition (EMT) phenotype and cellular plasticity. We found that A549 have a greater radiation-induced plasticity, as measured by E-cadherin, vimentin and double positive (DP) modulation, as compared to LLC. Additionally, migration was suppressed in A549-RR, as compared to A549. Subsequently, we confirmed that the LLC-RR and A549-RR are also more resistant to radiotherapy than their isogenic-matched counterpart in vivo. Remarkably, we found that the acquired radiation resistance also induced resistance to first-line chemotherapeutic cisplatin, but not carboplatin or oxaliplatin. This cross-resistance was attributed to induced elevated thiol levels. Decreasing the amount of thiols with buthionine sulfoximine (BSO), a gamma-glutamylcysteine synthetase inhibitor, sensitized the resistant cells to cisplatin, to levels similar as parental cells. Conclusions. By generating genetically-matched radiation resistant NSCLC tumor models we were able to identify and overcome cisplatin cross-resistance. This is an important finding arguing for multi-modality treatment regimens with the potential of improving clinical outcomes in the future. Citation Format: Samir V. Jenkins, Shruti Shah, Azemat Jamshidi-Parsian, Amir Mortazavi, Gunnar Boysen, Kieng B. Vang, Robert J. Griffin, Narasimhan Rajaram, Ruud P. Dings. Acquired radiation resistance induces thiol-dependent cisplatin cross-resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1088.

Abstract 6246: The MTA-cooperative PRMT5 inhibitor AM-9747 exhibits robust antitumor activity in combination with clinically relevant chemotherapies and targeted agents in MTAP null tumor models

Abstract Homozygous deletion of chr9p21, containing genes CDKN2A and MTAP, occurs in about 15% of cancers. MTAP loss, a key enzyme in the methionine and adenine salvage pathways, leads to the accumulation of its substrate MTA. MTA competes with the methyl donor SAM for binding to type II arginine methyltransferase PRMT5, placing PRMT5 in a hypomorphic state and vulnerable to further PRMT5 inhibition. MTA-cooperative PRMT5 inhibitors are an emerging class of therapeutics targeting MTAP null tumors. AMG 193, currently in Phase 1 trials, and its representative analog AM-9747 have broad spectrum activity in MTAP null tumor models across hematologic and solid tumor indications. Mechanistically, AM-9747 induces DNA damage, shown by increased phosphorylated H2AX, resulting in cell cycle arrest and senescence. Exploration of clinically relevant therapeutic combinations with standard of care (SOC) chemotherapies or targeted agents that could potentiate this DNA damage or target orthogonal pathways is a rational therapeutic approach. Here, we evaluated AM-9747 in combination with SOC chemotherapies and assessed synergy using the Chou-Talalay Method to generate Combination Index (CI) scores. SOC agents representing a variety of mechanisms of action (paclitaxel, carboplatin, gemcitabine, pemetrexed, irinotecan, 5-FU) were evaluated and results ranged from strongly synergistic (CI<0.3) to additive (CI=1) in a panel of non-small cell lung carcinoma (NSCLC) and pancreatic cancer cell lines. The SOC combinations augmented AM-9747 induced DNA damage resulting in increased cell cycle arrest and nuclear count assays confirmed the synergistic antiproliferative effects of the combinations. Combinations of AM-9747 and one strongly synergistic agent (carboplatin) and one moderately synergistic agent (paclitaxel) were evaluated in H292 NSCLC xenografts. Significant reductions in tumor burden compared to single agent treatments were observed with AM-9747 + paclitaxel (67% TGI) and AM-9747 + carboplatin (82% TGI). Additionally, roughly 2-3% of NSCLC tumors harbor both MTAP loss and a KRAS G12C mutation. To target both pathways we combined the FDA-approved KRAS G12C inhibitor sotorasib with AM-9747 and observed synergy (CI<0.6) in MIAPACA2 cells. Nuclear counts confirmed a greater cell growth inhibition in the combination and immunoblots confirmed on target inhibition of both pathways. Combination treatment of AM-9747 and sotorasib in LU99 NSCLC xenografts resulted in significant tumor regression compared to each single agent with 10/10 mice tumor free. This combination is being tested in additional MTAP null KRAS G12C mutant models. Overall, our data suggests that combining MTA-cooperative inhibitor AM-9747 with SOC or clinically relevant targeted agents is a compelling therapeutic strategy for the treatment of MTAP null cancers. Citation Format: Katherine Slemmons, Brian Belmontes, Siyuan Liu, Jodi Moriguchi, Antonia Policheni, Paul E. Hughes. The MTA-cooperative PRMT5 inhibitor AM-9747 exhibits robust antitumor activity in combination with clinically relevant chemotherapies and targeted agents in MTAP null tumor models. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6246.

Abstract 5616: Optical metabolic imaging of treatment-naive human NSCLC to determine long-term outcome

Abstract Lung cancer remains the leading cause of cancer deaths in the US and worldwide.​ The five-year survival rate of patients with non-small cell lung carcinoma (NSCLC) remains significantly low given that over half present with locally advanced or metastatic disease at time of diagnosis, and experience tumor recurrence following therapeutic intervention.​Current evaluation techniques to assess treatment response are lacking, given they are implemented several weeks after treatment completion and are solely based on anatomical changes in tumor size, forgoing other criteria such as functional or metabolic changes.​ There is a critical need to identify markers early on following diagnosis that are indicative of patient long-term outcome. Two photon microscopy (TPM) techniques are well-suited to provide non-invasive high-resolution information on cell metabolism within three-dimensional tissue. Specifically, two-photon excited fluorescence imaging of autofluorescent cofactors, nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD), can be used to metabolically characterize cancerous tissue. The goal of this study is to utilize the optical redox ratio (ORR) of FAD/[NADH+FAD] autofluorescence and NADH fluorescence lifetime decay to identify measurable differences in optical metabolic endpoints of human NSCLC that are indicative of their long-term outcome. Twenty-nine NSCLC specimens were obtained from the Lung Cancer Biospecimen Resource Network. They were resected from the lung prior to the patient receiving therapy. Clinical detail reports were used to evaluate the follow-up data of each patient and classify them into groups that reflected their eventual outcomes: responder (N=21), non-responder (N=18), non-metastatic (N=25), and metastatic (N=14). TPM was used to determine the ORR for each sample. NADH lifetime images were collected and fit to a biexponential model to separate the short (A1) and long (A2) components of free and bound NADH. We observed a significantly higher optical redox ratio for tumors within the metastatic group compared to non-metastatic. ​This is consistent with previous findings from our lab that revealed increases in the ORR with increasing metastatic potential in cells, as well as other studies reporting a decrease in NADH concentration in metastatic cancers.​ Additionally, a significantly shorter mean NADH lifetime in the metastatic tumor group was revealed when compared to non-metastatic. This stands in agreement with other studies highlighting decreases in the average lifetime of NADH in metastatic cells compared to non-metastatic. These results demonstrate the feasibility of using optical imaging of autofluorescence and lifetimes of metabolic cofactors to characterize treatment-naïve primary NSCLC tumors and determine differences in their optical metabolic endpoints that are indicative of their long-term outcome. Citation Format: Paola Monterroso Diaz. Optical metabolic imaging of treatment-naive human NSCLC to determine long-term outcome. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5616.

Robot-assisted thoracic surgery for stages IIB–IVA non-small cell lung cancer: retrospective study of feasibility and outcome

Robot-assisted thoracic surgery (RATS) for higher stages non-small cell lung carcinoma (NSCLC) remains controversial. This study reports the feasibility of RATS in patients with stages IIB–IVA NSCLC. A single-institute, retrospective study was conducted with patients undergoing RATS for stages IIB–IVA NSCLC, from January 2015 until January 2020. Unforeseen N2 disease was excluded. Data were collected from the Dutch Lung Cancer Audit database. Conversion rate, radical (R0) resection rate, local recurrence rate and complications were analyzed, as were risk factors for conversion. RATS was performed in 95 patients with NSCLC clinical or pathological stages IIB (N = 51), IIIA (N = 39), IIIB (N = 2) and IVA (N = 3). 10.5% had received neoadjuvant chemoradiotherapy. Pathological staging was T3 in 33.7% and T4 in 34.7%. RATS was completed in 77.9% with a radical resection rate of 94.8%. Lobectomy was performed in 67.4% of the total resections. Conversion was for strategic (18.9%) and emergency (3.2%) reasons. Pneumonectomy (p = 0.001), squamous cell carcinoma (p < 0.001), additional resection of adjacent structures (p = 0.025) and neoadjuvant chemoradiation (p = 0.017) were independent risk factors for conversion. Major post-operative complications occurred in ten patients (10.5%) including an in-hospital mortality of 2.1% (n = 2). Median recurrence-free survival was estimated at 39.4 months (CI 16.4–62.5). Two- and 5-year recurrence-free survival rates were 53.8% and 36.7%, respectively. This study concludes that RATS is safe and feasible in higher staged NSCLC tumors after exclusion of unforeseen N2 disease. It brings new perspective on the potential of RATS in higher stages, dealing with larger and more invasive tumors.

Expression Analysis of Five Different Long Non-Coding Ribonucleic Acids in Nonsmall-Cell Lung Carcinoma Tumor and Tumor-Derived Exosomes.

Long non-coding ribonucleic acids (LncRNAs) are recently known for their role in regulating gene expression and the development of cancer. Controversial results indicate a correlation between the tissue expression of LncRNA and LncRNA content of extracellular vesicles. The present study aimed to evaluate the expression of different LncRNAs in non-small cell lung cancer (NSCLC) patients in tumor tissue, adjacent non-cancerous tissue (ANCT), and exosome-mediated lncRNA. Tumor and ANCT, as well as serum samples of 168 patient with NSCLC, were collected. The GHSROS, HNF1A-AS1, HOTAIR, HMlincRNA717, and LINCRNA-p21 relative expressions in tumor tissue, ANCT, and serum exosomes were evaluated in NSCLC patients. Among 168 NSCLC samples, the expressions of GHSROS (REx = 3.64, p = 0.028), HNF1A-AS1 (REx = 2.97, p = 0.041), and HOTAIR (REx = 2.9, p = 0.0389) were upregulated, and the expressions of HMlincRNA717 (REx = -4.56, p = 0.0012) and LINCRNA-p21 (REx = -5.14, p = 0.00334) were downregulated in tumor tissue in contrast to ANCT. Moreover, similar statistical differences were seen in the exosome-derived RNA of tumor tissues in contrast to ANCT samples. A panel of the five lncRNAs demonstrated that the area under the curve (AUC) for exosome and tumor was 0.937 (standard error: 0.012, p value &lt; 0.0001). LncRNAs GHSROS, HNF1A-AS1, and HOTAIR showed high expression in tumor tissue and exosome content in NSCLC, and a panel that consisted of all five lncRNAs improved diagnosis of NSCLC.

Abstract 1632: An orthotopic model for luciferase-labeled human lung epithelial carcinoma with response to standard of care treatment

Abstract The human lung epithelial carcinoma A549 cell line was first developed in 1972 after culturing pulmonary carcinoma tissue from a 58-year-old Caucasian male. Similar to human non-small cell lung carcinoma (NSCLC), this cell line carries a KRAS mutation making an attractive model for drug discovery/oncology research applications. NSCLC tumors grow slower and less aggressively than small cell lung cancers, yet the 5-year survival rate for NSCLC is 25%. Thus, more relevant preclinical models are still needed to evaluate the potential therapeutic activities of agents that can be used in the clinic. Orthotopic implantation of luciferase-labeled cancer cell lines facilitate the evaluation of disease progression using bioluminescence in vivo imaging. Here we report the development of a novel model of orthotopically implanted Luciferase-labeled A549-luc cells, its tumor growth kinetics and response to standard of care therapy. To establish the orthotopic model, we implanted cells by direct injection into the left lung lobe through a small incision on the lateral thorax between the 6th and 7th rib. Disease progression was evaluated by testing cell implants at multiple cell inoculums and following each group for tumor growth using an IVIS Spectrum CT. In line with the observed slow growth of NSCLC, A549 tumor growth kinetics revealed long latency with a median survival of 69.5-days post-implant. Mean flux values correlated with the number of cells inoculated and clinical observations of respiratory distress. Gross necropsies provided visual evidence of masses in the left lung lobe and thoracic cavity. Following the A549-luc orthotopic model development, we sought to evaluate the survival benefit in response to standard of care agents Paclitaxel and the tyrosine kinase inhibitors Erlotinib and Afatinib. Paclitaxel monotherapy was the most active agent in a 101-day study. A single treatment cycle showed robust decrease tumor burden as determined via imaging during the first few weeks following treatment, but disease progression was apparent despite the overall improved survival over the vehicle control group. To establish durable responses, we evaluated the efficacy of Paclitaxel administered for two dosing cycles. Palbociclib, a cyclin-dependent kinase 4/6 inhibitor that has been recently identified as potential target in KRAS-mutant (NSCLC) was also evaluated. Our preliminary results show significant activity for both Palbociclib and Paclitaxel therapies in the A549-luc lung orthotopic xenograft model. This lung orthotopic model provides a sensible alternative that recapitulates the difficulties of treating NCSL tumors in addition to establishing a more clinically relevant model to evaluate cancer therapies compared to standard subcutaneous implanted models. Histopathological analysis of Ki67, Cyclin D1, and CDK4 will be presented from lungs of treated and control groups. Citation Format: Elizabeth Rainbolt, Andrew Wong, Chassidy Hall, Patrick Wood, Paula L. Miliani De Marval. An orthotopic model for luciferase-labeled human lung epithelial carcinoma with response to standard of care treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1632.

Abstract 1720: Macrophage biomarkers CD68 and CD163 correlate with NSCLC patient survival

Abstract Background: Immune cells within the tumor microenvironment (TME) play a vital role in regulating tumor progression. Therefore, immunotherapies that elicit anti-tumor responses are of great interest for the treatment of various cancers. Macrophages are a current immune cell type of interest due to the ability to polarize into anti-tumor (M1) and pro-tumor (M2) phenotypes. The density and phenotype of macrophages within the tumor and TME have been linked to prognosis in multiple types of solid tumors. Our hypothesis is that non-small cell lung carcinoma (NSCLC) patients with high immune infiltration and greater amounts of anti-tumor immune cells within the tumor compartment will have an increased time of survival compared to cancers with immune excluded or immune desert environments. Methods: One NSCLC tumor microarray (TMA) containing primary tumors, metastases, and normal tissue were stained via multiplex immunofluorescence (mIF) for 6 different immune markers: CD3, CD8, CD56, CD68, CD163, and PD-L1. The stained TMAs were analyzed utilizing Flagship Biosciences’ proprietary image analysis platform. Machine learning algorithms used cellular features to stratify cells as belonging to either the tumoral or stromal compartment. Core level expression data was pulled and represented on a whole-cohort basis. All staining and image analysis outputs were reviewed by a board-certified, MD pathologist. Kaplan-Meier curves were generated based on survival data in relation to the low, medium, and high expression of CD68 and/or CD163 in the whole tissue, as well as tumor and stromal compartments. Patients were also stratified into low (1 and 2) and high (3 and 4) cancer stages. Results: There is a correlation between patient survival and the presence or absence of macrophage markers CD68 and CD163. Specifically, lower levels of CD68+CD163- cells within the tumor and stroma compartments correlate with an increase in patient survival. There is also a correlation of a high level of expression of CD163+, CD68+CD163-, or CD68+CD163+ cells with increased patient survival in high stage patients compared to low stage patients. Specifically in high stage NSCLC patients, a higher level of CD163+ expression correlates with a reduced lifespan compared to patients with medium and low expression. Conclusion: Data generated through Flagship Biosciences’ image analysis platform showed a strong relationship between immune cell presence and localization with NSCLC patient survival. Altering the immune cells within the tumor to an anti-tumor immune environment could increase patient survival times. Further, utilizing Flagship Biosciences’ image analysis software to understand cancer immune microenvironments should be further utilized to aid in diagnosis and treatment decisions. Citation Format: Dannah Miller, Kate Hieber, Will Paces, Huong Nguyen, Adam Beharry, Roberto Gianani. Macrophage biomarkers CD68 and CD163 correlate with NSCLC patient survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1720.

Pathological Response and Immune Biomarker Assessment in Non-Small-Cell Lung Carcinoma Receiving Neoadjuvant Immune Checkpoint Inhibitors.

Simple SummaryRecently, the U.S. Food and Drug Administration (FDA) approved neoadjuvant immunotherapy plus chemotherapy for the treatment of resectable non-small-cell lung carcinoma (NSCLC) due to the clinical benefits reported in several clinical trials. In these settings, the pathological assessment of the tumor bed to quantify a pathological response has been used as a surrogate method of clinical benefit to neoadjuvant therapy. In addition, several clinical trials are including the assessment of tissue-, blood-, or host-based biomarkers to predict therapy response and to monitor the response to neoadjuvant treatment. In this manuscript, we provide an overview of current recommendations for the evaluation of pathological response and describe potential biomarkers used in clinical trials of neoadjuvant immunotherapy in resectable NSCLC.Lung cancer is the leading cause of cancer incidence and mortality worldwide. Adjuvant and neoadjuvant chemotherapy have been used in the perioperative setting of non-small-cell carcinoma (NSCLC); however, the five-year survival rate only improves by about 5%. Neoadjuvant treatment with immune checkpoint inhibitors (ICIs) has become significant due to improved survival in advanced NSCLC patients treated with immunotherapy agents. The assessment of pathology response has been proposed as a surrogate indicator of the benefits of neaodjuvant therapy. An outline of recommendations has been published by the International Association for the Study of Lung Cancer (IASLC) for the evaluation of pathologic response (PR). However, recent studies indicate that evaluations of immune-related changes are distinct in surgical resected samples from patients treated with immunotherapy. Several clinical trials of neoadjuvant immunotherapy in resectable NSCLC have included the study of biomarkers that can predict the response of therapy and monitor the response to treatment. In this review, we provide relevant information on the current recommendations of the assessment of pathological responses in surgical resected NSCLC tumors treated with neoadjuvant immunotherapy, and we describe current and potential biomarkers to predict the benefits of neoadjuvant immunotherapy in patients with resectable NSCLC.

Immuno-multiple reaction monitoring (iMRM) for quantitation of PD-L1 and PD-1-signaling proteins in non-small cell lung carcinoma (NSCLC).

2627 Background: More accurate predictive biomarkers of response to checkpoint inhibitors (CPIs) still is a major unmet need in oncology. PD-L1 immunohistochemistry (IHC) limitations include its analytical variability and the post-translational modifications of PD-1 signaling-associated proteins like glycosylation. Moreover, PD-L1 IHC is an imperfect surrogate of the tumor immune microenvironment, and immunoscoring is important but difficult to assess in a clinical setting. Proteomic based technologies can overcome these challenges, but the low concentration of these proteins and the presence of high background noise in formalin-fixed paraffin embedded (FFPE) tumors were limiting obstacles. In this study, we evaluate the benefit of a new approach we used with anti-peptide antibodies to purify surrogate peptides, while liquid chromatography (LC) was coupled to multiple reaction monitoring mass spectrometry (iMRM) to improve specificity and precision of protein quantitation. Methods: To determine the concentration of PD-L1, PD-1, PD-L2, NT5E, LCK and ZAP70, we used unique and well detectable proteolytic peptides as surrogates. In a refined protocol, we optimized protein extraction and digestion, peptide immuno-enrichment, LC and MRM parameters to maximize recovery, increase target-specific signal and reduce noise. Plus, we assessed the glycosylation status of PD-L1, PD-L2, and PD-1. The entire workflow was fully validated using 31 NSCLC FFPE tumors. PD-L1 quantitation by iMRM was compared to PD-L1 IHC clone 22C3. Results: On average, 71±29 µg (n = 52) of protein could be extracted from each 1–3 mm3 NSCLC tumor FFPE core. The optimized iMRM method allowed the quantitation of PD-L1 and PD-1 down to 21 amol on-column. Inter- and intra-day repeatability were well below FDA guidelines (coefficients of variation [CV] &lt; 20%) with average CVs of 5.2±4.0% (intra-day) and 4.5±2.6% (inter-day). Sample storage had no significant effect on peptide quantitation. The final multiplexed iMRM assay enables quantitation all targets and glycosylation states for &gt; 40 samples in only 3 days (including external calibration and quality controls) and was used to quantify the PD-1/PD-L1 axis proteins successfully in all 31 NSCLC FFPE tumors. PD-L1 expression ranged from 2 amol/μg to 61 amol/μg of total protein. As expected, iMRM results correlated moderately (R = 0.56, ρ &lt; 0.001) with PD-L1 IHC. PD-L1 glycosylation status ranged from 99.9±0.2%, and therefore did not explain the discrepancies between IHC and iMRM for these samples. Conclusions: Herein a robust iMRM workflow was developed for the quantitation of the PD-1/PD-L1 axis in FFPE. This proof-of-concept supports that MS-based assay can provide otherwise unavailable data (e.g., PD-L1 concentration, glycosylation status). CPI treated patient tumors are being currently processed to validate the predictive value of the assay.

Exon skipping induced by CRISPR-directed gene editing regulates the response to chemotherapy in non-small cell lung carcinoma cells

We have been developing CRISPR-directed gene editing as an augmentative therapy for the treatment of non-small cell lung carcinoma (NSCLC) by genetic disruption of Nuclear Factor Erythroid 2-Related Factor 2 (NRF2). NRF2 promotes tumor cell survival in response to therapeutic intervention and thus its disablement should restore or enhance effective drug action. Here, we report how NRF2 disruption leads to collateral damage in the form of CRISPR-mediated exon skipping. Heterogeneous populations of transcripts and truncated proteins produce a variable response to chemotherapy, dependent on which functional domain is missing. We identify and characterize predicted and unpredicted transcript populations and discover that several types of transcripts arise through exon skipping; wherein one or two NRF2 exons are missing. In one specific case, the presence or absence of a single nucleotide determines whether an exon is skipped or not by reorganizing Exonic Splicing Enhancers (ESEs). We isolate and characterize the diversity of clones induced by CRISPR activity in a NSCLC tumor cell population, a critical and often overlooked genetic byproduct of this exciting technology. Finally, gRNAs must be designed with care to avoid altering gene expression patterns that can account for variable responses to solid tumor therapy.

Hippocalcin-like 1 is a key regulator of LDHA activation that promotes the growth of non-small cell lung carcinoma.

Hippocalcin-like 1 (HPCAL1), a neuronal calcium sensor protein family member, has been reported toregulate cancer growth. As yet, however, the biological functions of HPCAL1 and its molecular mechanisms have not been investigated in non-small cell lung carcinoma (NSCLC). HPCAL1 expression in NSCLC samples was detected using immunohistochemistry, Western blotting and RT-PCR. The anticancer effects of HPCAL1 knockdown were determined by MTT, soft agar, cell cycle, oxygen consumption and reactive oxygen species assays. The effect of HPCAL1 knockdown on in vivo tumor growth was assessed using NSCLC cancer patient-derived xenograft models. Potentially interacting protein partners of HPCAL1 were identified using IP-MS/MS, immunoprecipitation and Western blottingassays. Metabolic alterations resulting from HPCAL1 knockdown were investigated using non-targeted metabolomics and RNA sequencing analyses. We found thatHPCAL1 is highly expressed in NSCLC tissues and is positively correlated with low survival rates and AJCC clinical staging in lung cancer patients. Knockdown of HPCAL1 strongly increased oxygen consumption rates andthe production of reactive oxygen species. HPCAL1 knockdown also inhibited NSCLC cell growth and patient-derived NSCLC tumor growth in vivo. Mechanistically, we found that HPCAL1 can directly bindto LDHA and enhance SRC-mediated phosphorylation of LDHA at tyrosine 10. The metabolomics and RNA sequencing analyses indicated thatHPCAL1 knockdown reduces amino acid levels and induces fatty acid synthesis through regulating the expression of metabolism-related genes. Additionally, rescued cells expressing wild-type or mutant LDHA in HPCAL1 knockdown cells suggest that LDHAmay serve as the main substrate of HPCAL1. Our data indicate that the effect of HPCAL1 knockdown on reducing SRC-mediated LDHA activity attenuates NSCLC growth. Our findings reveal novel biological functions and a mechanismunderlying the role of HPCAL1 in NSCLC growth in vitro and in vivo.

Somatic Mutation of BAP1 Can Lead to Expression Loss in Non-Small Cell Lung Carcinoma: Next Generation Sequencing and IHC Analysis in A Large Single Institute Cohort.

Introduction. As a tumor suppressor, germline and somatic inactivation of BRCA1 associated protein 1 gene (BAP1) is a common finding in mesothelioma, melanocytic tumors, clear cell renal cell carcinoma and several other epithelial, mesenchymal and neural tumors. Incidence of BAP1 genetic alterations and subsequent expression loss has not been well established in non-small cell lung carcinoma (NSCLC) by large-scale studies. Design. After IRB approval, a total of 356 NSCLC cases of our institution between July 2016 and June 2020 were reviewed. The study cohort consisted of 214 (60%) adenocarcinomas, 89 (25%) squamous cell carcinomas, and 53 (15%) diagnosed as "non-small cell lung carcinoma" without specified subtype. All tumors underwent comprehensive target cancer gene next generation sequencing (Oncomine Assay). The protein expression status of BAP1 was subsequently evaluated by immunohistochemistry. Results. BAP1 somatic mutations were detected in 8 NSCLC tumors (incidence: 2.2%). Tumors harboring BAP1 mutations were all diagnosed at advanced stage and carried at least one additional genetic alteration. Immunohistochemically, four tumors showed complete loss of BAP1 protein expression, including two adenocarcinomas which harbored different missense BAP1 mutations and another two with bioinformatically predicated deleterious frameshifting mutations. Conclusion. Compared with known BAP1 loss associated other malignancies, such as mesothelioma, inactivation of BAP1 by somatic mutation is a rare occurrence in NSCLC. BAP1 mutations and loss of expression in NSCLC are accompanied by other complex genetic alternations, suggesting BAP1 mutation maybe a late event NSCLC carcinogenesis.

Effects of combination treatment with durvalumab plus tremelimumab on the tumor microenvironment in non-small-cell lung carcinoma

The rapid development of immune checkpoint blockade (ICB) therapies has revolutionized the cancer treatment landscape and brightened the long-term forecast for many cancer patients. However, the specific genomic and proteomic changes in tumors treated with different ICB treatments have yet to be fully characterized. We treated four non-small-cell lung carcinoma (NSCLC) tumor digests ex vivo with the anti-PD-L1 antibody durvalumab (D) alone or in combination with the anti-CTLA-4 antibody tremelimumab (T) to explore changes in gene and protein expression associated with these ICB therapies. All four tumors showed a robust increase in interferon gamma (IFN-γ) production (100–300% higher than isotype control) in both D- and D + T-treated tumors. Three of the four tumors showed additional increases in IFN-γ production with D + T compared with D (40–70%). A substantial reduction in interleukin 10 (IL-10) was also found in three of the four tumors (reduced to 4–8%) in response to D and D + T. Conventional CD4 + /CD8 + populations and T cell activation markers increased after D and D + T treatment. D and D + T upregulated multiple IPA pathways involving T cell activation. D + T resulted in additional upregulation of Th1/Th2 pathways through a different set of genes, as well as greater reduction in genes involved in epithelial-mesenchymal transition (EMT), angiogenesis, and cancer stemness. Our results demonstrated that D + T augmented the effects of D in the microenvironment of this set of NSCLC tumors. The specific impact of D + T on the regulation of EMT, angiogenesis, and cancer stemness warrants further evaluation in a larger set of tumors.

Preliminary Study to Obtain Insights on the Proteomic Profile of Filipino Non-Small Cell Lung Carcinoma (NSCLC)

NSCLC remains to be the leading cause of cancer incidence and mortality in the Philippines. Early diagnosis, a better understanding of drug resistance mechanisms, and proper treatment monitoring are necessary to lower the incidence and mortality rate of NSCLC. As a proof of concept to investigate the proteomic profile of Filipino NSCLC, this study performed quantitative proteomic analysis to identify aberrant expressions in the tumor tissue relative to the adjacent normal tissue specimen of one Filipino NSCLC patient. A total of 4518 proteins were identified and from this, 1855 proteins were found to be significantly differentially expressed. Functional and pathway analyses were done to the 860 upregulated and downregulated proteins with at least four-fold expression change. The analysis revealed the possible activation of the upregulated protein MUC1, a known oncogenic driver involved in the stimulation of pathways that promote angiogenesis in NSCLC tumors and prevent apoptosis. Signal transducers and activators of transcription (STAT1 and STAT3), also found upregulated in the tumor specimen, are known to interact with MUC1, which results in the expression of proteins for cell proliferation. The analysis also suggests the stabilization of HIF, which may allow cell growth in the hypoxic tumor environment and aid in metabolic adaptation in tumor cells. The results also suggest the activation of EIF2 signaling that may lead to continuous translation of oncogenic proteins. Our data demonstrate the rich proteomic information that can be obtained from profiling of the NSCLC proteome and applications for a better understanding of NSCLC tumorigenicity. Further study should be performed on a larger cohort of Filipino NSCLC patients to provide the proteomic profile of Filipino NSCLC and extract information for biomarker and drug discovery. Data are available via ProteomeXchange with identifier PXD027710.

Abstract 470: Evaluation of two receptor tyrosine kinase (ROS1) clones by immunohistochemistry

Abstract Introduction: ROS1 is a receptor tyrosine kinase which regulates growth and cell division. ROS1 chromosomal rearrangements have been identified in a variety of human malignancies including non-small-cell lung carcinoma (NSCLC). However, patients diagnosed specifically with ROS1+ lung adenocarcinoma accounts for 1-2 percent of all NSCLC cases. Increased expression of ROS1 may suggest a ROS1 gene rearrangement. This is similar to ALK+ NSCLC tumors. Some ALK inhibitors can also be effective in tumors having the ROS1 mutation. Therefore, the development of targeted therapies has enhanced the importance of an accurate classification of the cancer subtypes. Materials and Methods: Immunohistochemistry: Both, the Biocare ROS1 rabbit monoclonal antibody (clone EPMGHR2) and the Roche VENTANA ROS1 (SP384) rabbit antibody were used in a ready-to-use format. ROS1 antibodies were run on the intelliPATH FLX, VALENT and the Ventana BenchMark Ultra platforms with in-house control and commercially available tissues from US Biolabs. Detection strategies utilized an HRP 2-step polymerized approach on the Biocare instruments, whereas the Optiview DAB IHC Detection kit was used on the Ventana platform. Fluorescence in Situ Hybridization (FISH): FISH was performed on a fully automated ONCORE Pro autostainer using the ROS1 (6q22) Break Apart (BA) (Orange/Green) FISH probe diluted in Biocare zipFISH hybridization buffer. Results: Initially, the NSCLC tissues were screened with a ROS1 BA FISH probe to identify the ROS1 mutation. Results indicated that the mutation was present on tumor cells throughout the tissue. When compared to FISH results on adjacent sections, a direct correlation between the ROS1 antibody staining and FISH results showed a good staining overlap. IHC staining on the intelliPATH FLX exhibited better signal-to-noise ratio for the Biocare ROS1 antibody compared to the Ventana antibody. A more concentrated Biocare antibody was required to obtain equivalent or better staining on the intelliPATH FLX than the Ventana ROS1 on the VENTANA ULTRA platform. However, the Biocare ROS1 in certain regions showed better staining than the Ventana ROS1. Biocare ROS1 at the same concentration produced a comparable staining on both the IntelliPATH FLX and the VALENT platforms. Conclusions: The availability of high quality ROS1 antibodies from alternative sources can be beneficial for labs performing lung cancer screening. Our rabbit monoclonal ROS1 antibody has been shown to produce strong and consistent signals with exceptional signal-to-noise. These results have been verified by using highly sensitive FISH probes in combination with a well-characterized commercially available ROS1 antibody. Citation Format: Julio S. Masabanda, Tatiana Scoggin, Joseph Vargas, Jason Ramos. Evaluation of two receptor tyrosine kinase (ROS1) clones by immunohistochemistry [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 470.

Exosomal miR-4443 promotes cisplatin resistance in non-small cell lung carcinoma by regulating FSP1 m6A modification-mediated ferroptosis

AimsExosomal transfer of miRNAs affects recipient cell proliferation and chemoresistance. Here, we aimed to investigate the role of exosomal miRNAs in controlling cisplatin resistance in non-small cell lung carcinoma (NSCLC). Main methodsPaired tumor and normal tissue-derived exosomes were collected from NSCLC patients with low or high responsiveness to cisplatin treatment. The results showed that the microRNA-4443 (miR-4443) level was upregulated in cisplatin-resistant NSCLC tumor tissue-derived exosomes compared with cisplatin-sensitive tissue-derived exosomes. Cisplatin-resistant cells (A549-R) were generated from the parental cells (A549-S). Resistant exosomes conferred cisplatin resistance by transferring miR-4443 to sensitive cells. Moreover, overexpression of miR-4443 inhibited FSP1-mediated ferroptosis induced by cisplatin treatment in vitro and enhanced tumor growth in vivo. Key findingsThrough bioinformatics analysis and luciferase assays, METTL3 was confirmed as a direct target gene of miR-4443. Further mechanistic analysis showed that miR-4443 regulated the expression of FSP1 in an m6A manner via METLL3. SignificanceOur findings provide more in-depth insight into the chemoresistance of NSCLC and support the therapeutic potential of targeting ferroptosis.