KRAS Non-small Cell Lung Cancer Research Articles

Metabolic profile and therapeutic vulnerabilities of multi-omic characterization ofKRAS/STK11/KEAP1 co-mutant non–small cell lung cancer (NSCLC).

8576 Background: KRAS-mutant NSCLC with co-occurring loss-of-function mutations in STK11 and KEAP1(KSK) are remarkably aggressive and poorly responsive to chemo- and immunotherapy. Novel therapeutic strategies are urgently needed to improve outcomes for patients with KRAS/STK11/KEAP1co-mutant NSCLC (KSK). We interrogated the transcriptomic landscape using a large real-world dataset of NSCLC to identify therapeutic vulnerabilities that may help guide treatment selections in KSK. Methods: KRAS mutant NSCLC clinical samples (N=7210) were tested with NextGen Sequencing of DNA (592-gene panel or whole exome sequencing) and RNA (whole transcriptome sequencing) at Caris Life Sciences (Phoenix, AZ). Specimens were stratified into KRASMUT/STK11MUT/KEAP1MUT (KSK; N=698), KRASMUT/STK11MUT/KEAP1WT (KS; N=786), KRASMUT/STK11WT/KEAP1MUT (KK; N=466), and KRASMUT/STK11WT/KEAP1WT (K; N=4536). Real-world overall survival (OS) data was obtained from insurance claims and investigated using Kaplan-Meier estimates. Additionally, an in vitro CRISPR screen, bulk RNA sequencing, and phospho-kinase arrays were performed in KRAS/STK11/KEAP1 co-mutant, single mutant, and wild-type cell lines to better characterize these models. Results: KEAP1mutations (median OS: KK=7.83 months, KSK=7.23 months) were strongly associated with poor OS compared to STK11 mutations (median OS: KS=17.6months). Pathways significantly upregulated in KSK clinical samples included fatty acid metabolism and redox pathways. When compared to single mutant or wild-type conditions, KSK clinical samples had significant up-regulation of genes involved in ferroptosis evasion and metabolism like SLC7A11(KSK/KK=1.28, KSK/KS=4.82, KSK/K=10.24; all q<0.01) and SCD1(KSK/KS=1.19, KSK/K=1.24; both q<0.01). To confirm our clinical findings, CRISPR/Cas9-based genetic screening identified SCD1, and SLC7A11 master regulators of fatty acid metabolism and ferroptosis, as a potential therapeutic target in the KSK cell lines. SCD1 inhibition augmented the effect of ferroptosis inducer, erastin. Targeting SCD1 led to global metabolomic changes in KSK cells, including key pathways involved in lipid and glucose metabolismas compared to single mutants or wild-type cells. Finally, pharmacological inhibition of SCD1 caused significant tumor regression and augmented the anti-tumor response of SLC7A11 inhibitor, imidazole ketone erastin (IKE), in KSK syngeneic mouse models. Conclusions: Our study is the first to highlight the importance of the ferroptosis regulators, SCD1-SLC7A11,in regulating unique metabolic and ferroptosis evasion pathways in KSK patient tumor and preclinical models. The study data furthers the understanding of ferroptosis in NSCLCand the potential to translate SCD1 inhibitors and ferroptosis inducers in KRAS NSCLC clinical trials.

Abstract 5825: Non-genetic determinants driving the evolutional trajectories of drug-tolerant-persisters in KRAS Non-small cell lung cancer

Abstract Rare cell populations manage to evade the effects of cancer therapies, ultimately leading to drug resistance and subsequent cancer relapse. These resilient populations, often referred to as "persisters," exhibit distinct molecular characteristics when compared to the broader tumor population. In the current standard of clinical care for non-small cell lung cancer (NSCLC), patients typically undergo a series of standard treatments, such as surgery followed by chemotherapy/immunotherapy, and then targeted therapy, based on the disease stages. This continues until drug resistance emerges, with little attention given to the state of these persister cells in response to these treatments. In the case of drug resistance in KRAS-mutated NSCLC, ongoing clinical investigations are exploring the combined efficacy of KRAS G12Ci inhibitors with drugs that target mitogen-activated protein kinase (MAPK) feedback reactivation, immunotherapy, and chemotherapy. Despite the myriad of combination therapies, persister populations invariably emerge. The manner in which these persisters evolve to withstand therapies remains elusive. We employed a DNA barcode lineage tracing analysis coupled with mathematical modeling to decode persister evolution to therapies targeting different pathways, e.g., KRAS+ SHP2, KRAS+CDK4/6, and KRAS+MCL-1. Our model reveals that rapidly emerging persister populations are predetermined and do not exhibit clear genetic alterations. In some cells, common persisters exist in response to different therapies. Single-cell ATAC-RNA sequencing showed that these persisters are enriched in chromatin-binding of transcription factors that regulate classic non-homologous end-joining (cNHEJ) DNA repair (ZNF384), interferon response (IRF1), and stem-like characteristics (FOXP1), along with the activation of an IFN-γ transcriptional signature. These findings underscore the connection between specific DNA repair processes, chromosomal instability, and resistance to KRAS G12Ci. In other cells, however, distinct persister populations exist to different therapies, leading to the hypothesis that these diverse persister populations can be targeted orthogonally or sequentially to achieve tumor regression. In summary, our study unveils the heterogeneity in persister evolution trajectories in KRAS NSCLC. Our platform identifies targetable persister populations in NSCLC models and offers a proof-of-concept for non-standard strategies to combat drug resistance based on persister cell states. Citation Format: Chendi Li, Christopher J. Graser, Qian Qin, Anahita Nimbalkar, Usman Syed, Barbara Karakyriakou, Sarah Clark, Anne Y. Saiki, Paul E. Hughes, Christopher Ott, Luca Pinello, Franziska Michor, Aaron Hata. Non-genetic determinants driving the evolutional trajectories of drug-tolerant-persisters in KRAS 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 5825.

Abstract 1522: Tumor-associated fibrosis leads to an increase in T-cell exhaustion and impairs tumor control in non-small cell lung cancer

Abstract Lung cancer is the leading cause of cancer-related mortality with non-small cell lung cancer (NSCLC) being the most predominant type. Recent studies have shown the efficacy of anti-PD1 inhibitors which improved overall survival. However, this efficacy is limited to a subset of patients due to the intrinsic tumor resistance to immune checkpoint inhibitors. Our group recently demonstrated that tumor-associated fibrosis negatively correlates with T cell-mediated immune response in lung cancer. This is largely dependent on Col13a1-expressing cancer-associated fibroblasts (CAFs), which result in recruiting the immunosuppressive macrophages and regulatory T cells while limiting dendritic cells and CD8 T cell infiltration. Here, we characterize the effect of fibrosis on the TME including TILs and macrophages using an orthotopic KRAS and P53-driven murine NSCLC model (KPL86-mCher model) with FITC-induced fibrosis.Fibrosis significantly increased the number of cancer-associated fibroblasts and collagen density in KPL86-mCher lung tumors. Following carboplatin + pemetrexed and Anti-PD1 treatment, we observed no increase in tumor-infiltrating CD4+ and CD8+ T cells or decrease in tumor burden when compared with the non-fibrotic tumors. Rather, we observed a significant increase in exhausted T cells marked by high Tim3, PD1, and TOX in fibrotic KPL86-mCher tumors. Corresponding to these impaired T-cell responses, we found an increase in tumor-infiltrating alveolar macrophages with immunosuppressive phenotype under fibrotic tumor conditions. Our data suggests that tumor-associated fibrosis leads to an increase in CD8+ T cell exhaustion as well as immunosuppressive macrophage infiltration in our spontaneously derived murine model on NSCLC. Overall, this indicates that targeting tumor fibrosis may significantly improve the efficacy of immunotherapy which would have translational implications for patients with immunotherapy-resistant NSCLC. Citation Format: Usman Y. Panni, Varun Shenoy, Brett Knolhoff, Faiz Ahmed, Brett Herzog, William G. Hawkins, John A. Olson, David G. DeNardo. Tumor-associated fibrosis leads to an increase in T-cell exhaustion and impairs tumor control 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 1522.

Abstract B081: Aurora kinase A inhibition overcomes adaptive resistance to KRAS G12C inhibitor by G1-checkpoint induced apoptosis in KRAS non-small cell lung cancer

Abstract Cancer cells gain drug-tolerant states and evade therapy. In response to KRAS G12C inhibitor (G12Ci), KRAS mutant non-small cell lung cancer (NSCLC) cells maintain a drug-tolerant state by aurora kinase A (AURKA). AURKA can phosphorylate c-Raf to maintain new KRAS signaling, however, how AURKA becomes activated to cause KRAS G12Ci resistance is unclear. We show here that KRAS G12C + AURKA inhibition cause synthetic lethality in KRAS G12C NSCLC cells. LY3499446 (KRAS G12Ci) and LSN3321213 (aurora kinase A inhibitor) induced apoptosis that is independent of inhibited MAPK reactivation. Using high-content imaging that tracks single-cell fate during treatment, we observed that single-agent KRAS G12Ci induces G1 arrest in a sub-population of cells. Upon co-treatment with G12C + AURKAi, cells that are halted in G1 phase undergo early apoptosis, while those that initially evade G1 arrest and proceed through G2/M undergo apoptosis in subsequent G1. These data suggest the hypothesis that AURKA inhibition may increase the probability of G1 checkpoint-induced apoptosis by facilitating chromosomal misalignment and genomic instability in G2. In summary, we provide pre-clinical rationale for clinical testing of KRAS G12C + AURKA inhibitors. We also suggest a novel mechanism explaining the dependency of KRAS G12C resistant subpopulations on AURKA, leading to the opportunity to investigate the role of genomic instability in conferring KRAS G12Ci adaptive resistance. Citation Format: Chendi Li, Jeremy Chang, Christopher J Graser, Usman M Syed, Anahita Nimbalkar, Yi Shen, Steve Altschuler, Lani Wu, Franziska Michor, Xueqian Gong, Aaron N Hata. Aurora kinase A inhibition overcomes adaptive resistance to KRAS G12C inhibitor by G1-checkpoint induced apoptosis in KRAS non-small cell lung cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B081.

Molecular characteristics of KRAS mutations in Chinese patients with cancer.

e15070 Background: Sotorasib, the first KRAS G12C inhibitor, has been approved for the treatment of non-small cell lung cancer (NSCLC) patients with KRAS G12C mutation-positive. Understanding the molecular characteristics of KRAS in Chinese patients with cancer is imperative, which is conducive to screening the beneficiary groups. Here, we focus on the molecular characterization of KRAS in NSCLC, colorectal cancer (CRC), pancreatic cancer (PC), and gastric cancer (GC). Methods: This study enrolled 17,775 pan-cancer patients detected by next-generation sequencing (NGS) from June 2021 to February 2022, in which NSCLC, CRC, PC and GC were 48.67% (8651/17775), 10.87% (1933/17775), 1.92% (342/17775) and 5.37% (955/17775), respectively. Results: The KRAS mutation rate in pan-cancer is 16.28% (2893/17775). In NSCLC, CRC, PC and GC cohorts, the mutation rates of KRAS were 13.28% (1149/8651), 50.34% (973/1933), 66.67% (228/342) and 7.64% (73/955), respectively. In NSCLC cohort, 1274 KRAS mutations were detected, and the subtypes were concentrated in G12C (346;27.16%), G12D (205;16.10%), G12V (194;15.23%), G12A (86;6.75) and Q61H (57;4.47%). In CRC cohort, 1094 KRAS mutations were detected. The subtypes were mainly distributed in G12D (350;31.40%), G13D (184;16.82%), G12V (180;16.45%), A146P (66;6.03%) and G12C (49;4.48%). In PC cohort, 251 KRAS mutations were detected, and the subtypes were concentrated in G12D (109;43.43%), G12V (70;27.89%), G12R (32;12.75%), G12C (9;3.59%) and Q61H (9;3.59%). In GC cohort, 82 KRAS mutations were detected. The subtypes of these mutations were concentrated in G12D (23;28.05%), G13D (12;14.63%), Q61H (7;8.54%), G12V (5;6.10%) and Q61R (5;6.10%). Conclusions: In NSCLC, CRC, PC and GC cohorts, K RAS mutations were concentrated in exon 2, accounting for 78.41% (999/1274), 81.63% (893/1094), 91.63% (230/251) and 64.63% (53/82), respectively. In NSCLC cohort, KRAS G12C was the molecular subtype with the highest mutation rate. However, in other cohorts, KRAS G12D was the predominant molecular subtype. G12D mutation will become the next research hotspot, and the breakthrough will help to further expand the beneficiary population of KRAS mutations.

Abstract 5735: Novel KRAS G12D degrader ASP3082 demonstrates in vivo, dose-dependent KRAS degradation, KRAS pathway inhibition, and antitumor efficacy in multiple KRAS G12D-mutated cancer models

Abstract KRAS is one of the most frequently mutated oncogenes in various cancers. Among KRAS mutations, KRAS G12D is the most frequent driver mutation and is found in approximately 34% of patients with pancreatic ductal adenocarcinoma (PDAC), 12% of patients with colorectal cancer (CRC), 4% of patients with lung adenocarcinoma, and in a subset of patients with other solid tumors. We have identified ASP3082 as a novel KRAS G12D degrader with high potency and selectivity. Here, we have evaluated in vivo antitumor activities and pharmacodynamic properties of ASP3082 in various KRAS G12D-mutated xenograft models. ASP3082 was intravenously administered to KRAS G12D-mutated cancer-xenograft-bearing mice, and plasma and tumors were collected at defined time points. The drug concentration and KRAS-related signal transduction were measured in the xenograft model. The in vivo efficacy of ASP3082 monotherapy was confirmed in multiple xenograft mouse models following intravenous administration. Once-weekly intravenous administration of ASP3082 induced dose-dependent and significant growth inhibition of KRAS G12D PDAC tumors, resulting in profound tumor regression without body weight loss. ASP3082 showed sustained concentrations in the xenograft tumors after a single intravenous administration and decreased KRAS G12D-mutated-protein levels according to the duration of the sustained ASP3082 concentrations. ASP3082 also demonstrated marked inhibition of extracellular signal-regulated kinase phosphorylation and its downstream genes, and potently induced cleavage of caspase 3. In addition, ASP3082 exhibited potent antitumor activities in not only PDAC but also CRC and non-small cell lung cancer KRAS G12D-mutated mouse models. These studies demonstrated that ASP3082 induced degradation of KRAS G12D protein, inhibition of KRAS downstream molecules, and an apoptotic response to show dose-dependent antitumor activity in multiple KRAS G12D-mutated cancer models. ASP3082 is a potential therapeutic agent for patients with tumors harboring the KRAS G12D mutation. Currently, a phase 1 clinical trial is underway in patients with previously treated, locally advanced or metastatic solid tumors with KRAS G12D mutation (NCT05382559). Citation Format: Takeyuki Nagashima, Tomohiro Yoshinari, Yoshihiro Nishizono, Mamoru Tasaki, Kohei Inamura, Hiroki Ishioka, Atsushi Suzuki, Fumio Osaki, Yosuke Yamanaka, Masahiko Hayakawa. Novel KRAS G12D degrader ASP3082 demonstrates in vivo, dose-dependent KRAS degradation, KRAS pathway inhibition, and antitumor efficacy in multiple KRAS G12D-mutated cancer 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 5735.

Abstract 3868: Aurora kinase A inhibition overcome adaptive resistance to KRAS G12C inhibitor by G1-checkpoint induced apoptosis in KRAS non-small cell lung cancer

Abstract Cancer cells gain drug-tolerant states and evade therapy. In response to KRAS G12C inhibitor (G12Ci), KRAS mutant non-small cell lung cancer (NSCLC) cells maintain a drug-tolerant state by aurora kinase A (AURKA). AURKA can phosphorylate c-Raf to maintain new KRAS signaling, however, how AURKA becomes activated to cause KRAS G12Ci resistance is unclear. We show here that KRAS G12C + AURKA inhibition cause synthetic lethality in KRAS G12C NSCLC cells. LY3499446 (KRAS G12Ci) and LSN3321213 (aurora kinase A inhibitor) induced apoptosis that is independent of inhibited MAPK reactivation. Using high-content imaging that tracks single-cell fate during treatment, we observed that single-agent KRAS G12Ci induces G1 arrest in a sub-population of cells. Upon co-treatment with G12C + AURKAi, cells that are halted in G1 phase undergo early apoptosis, while those that initially evade G1 arrest and proceed through G2/M undergo apoptosis in subsequent G1. These data suggest the hypothesis that AURKA inhibition may increase the probability of G1 checkpoint-induced apoptosis by facilitating chromosomal misalignment and genomic instability. In summary, we provide clinical rationale for clinical testing of KRAS G12C + AURKA inhibitors. We also suggest a novel mechanism explaining the dependency of KRAS G12C resistant subpopulations on AURKA, leading to the opportunity to investigate the role of genomic instability in conferring KRAS G12Ci adaptive resistance. Citation Format: Chendi Li, Jeremy Chang, Mohammed U. Syed, Anahita Nimbalkar, Yi Shen, Steve Altschuler, Lani Wu, Xueqian Gong, Aaron Hata. Aurora kinase A inhibition overcome adaptive resistance to KRAS G12C inhibitor by G1-checkpoint induced apoptosis in KRAS non-small cell lung cancer. [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 3868.

Abstract 3867: Chromatin modification driving sub-clonal resistance to KRAS G12C combination therapies in KRAS mutant non-small cell lung cancer

Abstract The FDA approval of the KRAS G12C inhibitor (G12Ci) sotorasib and the advancement of similar drugs into clinical trials marks a major milestone in treating KRAS G12C non-small cell lung cancer (NSCLC). However, not all patients respond (sotorasib - ORR = 37.1%, adagrasib - 43%, JDQ443 - 35%), motivating preclinical and clinical investigation into mechanisms of intrinsic and acquired resistance. For instance, clinical studies have reported on-target KRAS mutations and preclinical studies have demonstrated mitogen-activated protein kinase (MAPK) feedback reactivation including EGFP, SHP2, and WT RAS signaling. In response to targeted therapies, sub-populations of cells can enter quiescence or specific epigenetic-driven states that confer drug tolerance. However, epigenetic states defining drug-tolerant persister populations and contributing to adaptive resistance to KRAS G12Ci have not been reported. Using a lineage tracing barcoded system, we identify distinct and reversible subpopulations defined by specific chromatin and transcriptional states in KRAS NSCLC cell lines that contribute to KRAS G12Ci resistance in vitro, even prior to drug treatment. We observed that specific states, including activation of histone demethylation and SWI/SNF complex, may contribute to MAPK reactivation-driven resistance. These results suggest potential epigenetic vulnerabilities that can be exploited to improve the response to KRAS G12Ci. Moreover, we observed distinct persister subpopulations with resistance to KRAS G12Ci combination co-targeting orthogonal pathways (SHP2, CDK4/6, PI3K, and MCL-1), raising the possibility that distinct epigenetic-transcriptional states contribute to differential drug response and clonal evolution of persisters. Collectively, these results suggest that more complete tumor regression may be achieved by orthogonal strategies that target different resistant populations within the same tumor. Citation Format: Chendi Li, Qian Qin, Mohammed Usman Syed, Anahita Nimbalkar, Barbara Karakyriakou, Sarah E. Clark, Anne Y. Saiki, Paul E. Hughes, Chris Ott, Luca Pinello, Aaron N. Hata. Chromatin modification driving sub-clonal resistance to KRAS G12C combination therapies in KRAS mutant non-small cell lung cancer. [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 3867.

HDAC inhibitor ITF2357 reduces resistance of mutant-KRAS non-small cell lung cancer to pemetrexed through a HDAC2/miR-130a-3p-dependent mechanism

BackgroundHistone deacetylases (HDAC) contribute to oncogenic program, pointing to their inhibitors as a potential strategy against cancers. We, thus, studied the mechanism of HDAC inhibitor ITF2357 in resistance of mutant (mut)-KRAS non-small cell lung cancer (NSCLC) to pemetrexed (Pem).MethodsWe first determined the expression of NSCLC tumorigenesis-related HDAC2 and Rad51 in NSCLC tissues and cells. Next, we illustrated the effect of ITF2357 on the Pem resistance in wild type-KARS NSCLC cell line H1299, mut-KARS NSCLC cell line A549 and Pem-resistant mut-KARS cell line A549R in vitro and in xenografts of nude mice in vivo.ResultsExpression of HDAC2 and Rad51 was upregulated in NSCLC tissues and cells. Accordingly, it was revealed that ITF2357 downregulated HDAC2 expression to diminish the resistance of H1299, A549 and A549R cells to Pem. HDAC2 bound to miR-130a-3p to upregulate its target gene Rad51. The in vitro findings were reproduced in vivo, where ITF2357 inhibited the HDAC2/miR-130a-3p/Rad51 axis to reduce the resistance of mut-KRAS NSCLC to Pem.ConclusionTaken together, HDAC inhibitor ITF2357 restores miR-130a-3p expression by inhibiting HDAC2, thereby repressing Rad51 and ultimately diminishing resistance of mut-KRAS NSCLC to Pem. Our findings suggested HDAC inhibitor ITF2357 as a promising adjuvant strategy to enhance the sensitivity of mut-KRAS NSCLC to Pem.

130 (PB120) - Characterization of KRAS-driven NSCLC cell lines with diverse mutational landscape and assessment of their response to MYC inhibition

Introduction: Lung cancer is the second most common cancer type both in males and females and the leading cause of cancer death worldwide. Inside lung cancer, Non-Small-Cell Lung Cancer (NSCLC) represents around 85% of the cases, where KRAS is the leading mutated oncogene (∼25%) and confers poor prognosis and a high risk of tumor recurrence. Subsets of mutant KRAS NSCLC have been described based on the presence of concurrent mutations in tumor suppressor genes (TSGs), being the most common TP53, KEAP1 and LKB1 (also called STK11).

79P Molecular characterization of KRAS NSCLC all stages: A single-center cohort

Kirsten rat sarcoma viral oncogene mutation (KRASm) is detected in approximately 25% of non-small cell lung cancer (NSCLC) adenocarcinoma patients (pts). As Next-generation sequencing (NGS) has been increasingly employed, diverse KRASm subtypes (subt) with different prognoses, incidences of co-mutations and characteristics have been described.

Abstract 48: Molecular characteristics of HRAS mutated non-small cell lung cancer (NSCLC)

Abstract Background: Alterations in the RAS pathway have been linked to tumorigenesis, apoptosis, metabolism and angiogenesis. Mutations of KRAS in NSCLC are more frequent and better characterized, however, other family members such as HRAS remain under investigated and RAS remains a challenging therapeutic target. HRAS has been indirectly targeted with tipifarnib, a farnesyltransferase inhibitor rendering HRAS inactive in head and neck tumors. Here, we characterize the incidence, genomic landscape, and clinical context of HRAS alterations in NSCLC. Methods: A total of 29,767 NSCLC tumor samples underwent comprehensive molecular profiling at Caris Life Sciences. Analyses included next generation sequencing of DNA (592 Gene Panel, NextSeq, or whole exome sequencing, NovaSeq), RNA (NovaSeq, whole transcriptome sequencing, WTS) and immunohistochemistry. MAPK activation was assessed using the MPAS gene expression signature. Wilcoxon, Fisher’s exact, or Dunnett’s tests were used to determined statistical significance (displayed as p value without and q value with multi-comparison correction). Overall survival was calculated from date of tissue collection to last contact from insurance claims data and used for Kaplan-Meier analysis. Comparisons were conducted between HRAS mutated tumors and the entire NSCLC general cohort (GC). Results: HRAS mutations (Hm) were detected in 128 of 29767 NSCLC samples (0.4%) and were significantly enriched in older patients (median age, 71 vs. 69 years; q<0.01) and squamous histology (57.8% vs 21.8%, q<0.0001) compared to GC. Smoking status was not associated with HRAS mutational status (p=0.19). The most prevalent loci of hotspot mutations in Hm tumors were G13 (42.2%), followed by Q61 (33.6%) and G12 (21.1%). HRAS was not prognostic for overall survival (HR = 1.06, 95% CI [0.83-1.35], p=0.64), but for HRAS G13 mutant subset of NSCLC there was a trend towards worse prognosis (HR = 1.31, 95% CI [0.91-1.88], p =0.14). Hm-positive tumors harbored significantly more PIK3CA mutations (16.9% vs 5.5%, q<0.05) but less KRAS (3.2% vs 27.4%, q<0.05) and EGFR mutations (0.8% vs 11.9%, q<0.05) compared to GC. In addition, Hm displayed dMMR/MSI deficiency (2.6% vs 0.7%, p <0.05) more frequently, but had a comparable percentage of TMB-H tumors (34.2% vs 40.2%, p = 0.16) and similar median PD-L1 expression (54.7% vs 60.3%, p = 0.21) when comparing to GC. Lastly, MAPK pathway activation score was relatively higher in Hm compared to GC (-0.26 vs -0.42) with Q61 being the highest group (0.04 vs -0.42, p = 0.37). Conclusions: HRAS mutations are detectable but uncommon events in NSCLC and significantly enriched in squamous histology. HRAS mutations often occur with PIK3CA co-mutations and trended towards higher activation of MAPK pathway and MSI-H frequency. This warrants further investigation on possible clinical applications of HRAS pathway inhibitors and utility of immune checkpoint inhibitors for this subset of NSCLC. Citation Format: Asaad Trabolsi, Estelamari Rodriguez, Samuel Alexander Kareff, Michael Korn, Joanne Xiu, Stephen Liu, Philip walker, Patrick Ma, Hirva Mamdani, Jorge Nieva, Hossein Borghaei, Chadi Nabhan, Misako Nagasaka, Sonam puri, Gilberto Lopes. Molecular characteristics of HRAS mutated non-small cell lung cancer (NSCLC) [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 48.

A phase 2 study of VS-6766 (RAF/MEK clamp) RAMP 202, as a single agent and in combination with defactinib (FAK inhibitor) in recurrent KRAS mutant (mt) and BRAF mt non–small cell lung cancer (NSCLC).

TPS9147 Background: KRAS is mutated (mt) in 25% of NSCLC adenocarcinoma, with KRAS G12V and G12C mt occurring in ̃7% and ̃13% of patients (pts), respectively. Whereas G12C inhibitors have demonstrated promising activity in pts with KRAS G12C NSCLC, KRAS G12V NSCLC remains an unmet need. BRAF mt occurs in ̃4% of NSCLC with roughly equal split between BRAF V600E and non-V600E. VS-6766 is a small molecule RAF/MEK clamp that inhibits BRAF, CRAF and MEK, enabling VS-6766 to block MEK signaling without compensatory activation of MEK observed with MEK-only inhibitors. VS-6766 potently inhibits proliferation of KRAS and BRAF mt cell lines. Focal adhesion kinase (FAK) activation is a putative resistance mechanism to RAF and MEK inhibition, and defactinib, a small molecule FAKi, has shown synergistic anti-tumor activity with VS-6766 in KRAS mt NSCLC models. In a KRAS G12V mt NSCLC mouse model, which was shown to be especially dependent on CRAF, VS-6766 induced strong tumor regressions both as monotherapy and in combination with FAKi (Coma AACR 2021). Clinically, VS-6766 monotherapy has shown responses in KRAS mt NSCLC including pts with KRAS G12V and in pts with BRAF V600E solid tumors (Guo 2020; Martinez-Garcia 2012). The combination of VS-6766 + defactinib is currently being evaluated in the Investigator Sponsored FRAME study. In an updated analysis of response in 20 pts with KRAS mt NSCLC, there were 2 confirmed PRs, 1 unconfirmed PR and 10 SDs (ORR = 15%; DCR = 65%) with 7/20 pts remaining on treatment for ≥24 weeks. The 2 pts with KRAS G12V NSCLC both had confirmed PRs (ORR = 100%). This combination regimen exhibited a manageable safety profile with no NSCLC pts discontinuing for adverse events (Krebs AACR 2021). Methods: This is an international phase 2, adaptive, multicenter, randomized, open label study designed to evaluate the efficacy and safety of VS-6766 vs. VS-6766 + defactinib in pts with recurrent KRAS or BRAF mt NSCLC (NCT04620330). Part A will determine the optimal regimen, either VS-6766 monotherapy or VS-6766 + defactinib based on pts with KRAS G12V. Part A will consist of 5 NSCLC arms: Arm 1 VS-6766 monotherapy in KRAS G12V, Arm 2 VS-6766 + defactinib in KRAS G12V, Arm 3 the combination in KRAS non-G12V, Arm 4 the combination in BRAF V600E and Arm 5 the combination in BRAF non-V600E. Part B will determine the efficacy of the optimal regimen identified in Part A. Pts must have histologic or cytologic evidence of NSCLC, measurable disease according to RECIST V1.1, known KRAS or BRAF mt and at least 1 prior systemic therapy (appropriate therapy for activating mutation and/or platinum-based therapy). Part A will enroll 102 pts Arms 1 and 2 (KRAS G12V), and Arms 4 and 5 (BRAF V600E and non-V600E) are currently open. Arm 3 (KRAS non-G12V) enrollment is completed. The total number of pts in Part B will be determined by results from Part A. Clinical trial information: NCT04620330.

Ceramide Kinase Inhibition Drives Ferroptosis and Sensitivity to Cisplatin in Mutant KRAS Lung Cancer by Dysregulating VDAC-Mediated Mitochondria Function.

Our findings depict how CERK inhibition may serve as a new key point in combination therapeutic strategy for NSCLC, specifically precision therapeutics targeting NSCLC possessing a KRAS mutation.

Transcriptomic Mapping of Non-Small Cell Lung Cancer K-RAS p.G12C Mutated Tumors: Identification of Surfaceome Targets and Immunologic Correlates.

Targeting K-RAS-mutant non-small cell lung cancer (NSCLC) with novel inhibitors has shown promising results with the recent approval of sotorasib in this indication. However, progression to this agent is expected, as it has previously been observed with other inhibitors. Recently, new immune therapeutics, including vectorized compounds with antibodies or modulators of the host immune response, have demonstrated clinical activity. By interrogating massive datasets, including TCGA, we identified genes that code for surface membrane proteins that are selectively expressed in K-RAS mutated NSCLC and that could be used to vectorize novel therapies. Two genes, CLDN10 and TMPRSS6, were selected for their clear differentiation. In addition, we discovered immunologic correlates of outcome that were clearly de-regulated in this particular tumor type and we matched them with immune cell populations. In conclusion, our article describes membrane proteins and immunologic correlates that could be used to better select and optimize current therapies.

Targeting KRAS in NSCLC: Old Failures and New Options for "Non-G12c" Patients.

Simple SummaryNon-small cell lung cancer (NSCLC) with Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) mutation comprises a specific subgroup of patients who are particular in terms of several clinical and molecular aspects. Indeed, there is a clear medical need to find specific and effective treatments for these patients, since KRAS mutation positive NSCLC has demonstrated to be—in some cases—less responsive to standard therapies. For many years, targeting KRAS mutations has been considered an impossible challenge. The scenario is further complicated by the possible role of co-mutations that could influence both tumour microenvironment and drug response. However, some promising preclinical and clinical data are expected to change the treatment landscape of this hard-to-treat disease. Indeed, tumors harbouring G12C mutations could now be effectively targeted with specific inhibitors based on clinical trial results. This review aims to provide a clinical update on potential therapies for advanced NSCLC with KRAS mutations other than the more common G12C, for which good results have already been achieved, particularly focusing on clinical trials, molecules and mechanisms currently under investigation.Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) gene mutations are among the most common driver alterations in non-small cell lung cancer (NSCLC). Despite their high frequency, valid treatment options are still lacking, mainly due to an intrinsic complexity of both the protein structure and the downstream pathway. The increasing knowledge about different mutation subtypes and co-mutations has paved the way to several promising therapeutic strategies. Despite the best results so far having been obtained in patients harbouring KRAS exon 2 p.G12C mutation, even the treatment landscape of non-p.G12C KRAS mutation positive patients is predicted to change soon. This review provides a comprehensive and critical overview of ongoing studies into NSCLC patients with KRAS mutations other than p.G12C and discusses future scenarios that will hopefully change the story of this disease.

P52.04 Histone Deacetylase 6 Inhibition Reveals Metabolic Vulnerabilities in KRAS Non-Small Cell Lung Cancer

Lung tumors are characterised has having high glucose and lactate use, and high heterogeneity in their metabolic pathways. Decades of research provides comprehensive knowledge of the rewired metabolic programs driven by oncogenic KRAS, including glucose metabolism, fatty acid synthesis, glutamine metabolism, autophagy signaling and redox homeostasis. KRAS mutations in non- small cell lung cancer (NSCLC) often occur with co-mutations in other genes such as TP53 and LKB1, and these co-existing genetic mutations can determine clinical response.

Abstract 1104: Repotrectinib increases effectiveness of MEK inhibitors in KRAS mutant cancer models

Abstract KRAS is the most frequently mutated oncogene in cancers, accounting for approximately 25% of non small cell lung cancer (NSCLC), 45% of colorectal cancer (CRC), and 75% of pancreatic cancer. KRAS G12D and G12V mutations account for a large percent of mutant KRAS cancers (36% of NSCLC; 57% of CRC; 71% of pancreatic). MEK1/2 are critical downstream effectors of KRAS signaling and preclinical studies in KRAS mutant models show sensitivity to MEK inhibitors (MEKi). However, clinical studies of single agent MEKi or combinations with docetaxel in mutant KRAS NSCLC patients were associated with low response rates. Preclinical studies show that effectiveness of MEK inhibition can be limited by multiple resistance mechanisms such as compensatory upregulation of PI3K/AKT via SRC/FAK signaling, or activation of the JAK2/STAT3 pathway. Repotrectinib is a next-generation ROS1/TRK inhibitor with SRC/FAK/JAK2 inhibitory potencies which may suppress adaptive resistance to MEK inhibitors. In the current study, repotrectinib combinations with KRAS signaling network inhibitors including MEK (trametinib, selumetinib), MEK/RAF (VS-6766), ERK (LY3214996), SHP2 (TNO155) were explored. Repotrectinib/trametinib and repotrectinib/VS-6766 combinations yielded significant effects on cancer cell viability in NSCLC and pancreatic patient-derived spheroid models harboring KRASG12D and KRASG12V mutations. The repotrectinib/trametinib combination in A427 cells (NSCLC KRASG12D) exhibited increased inhibition of pAKT and pS6 compared to single agent treatments. This coincided with greater upregulation of p27 and elevated PARP cleavage, resulting in enhanced induction of apopotosis. To assess acquired MEKi resistance, several KRAS mutant cancer models were cultured under trametinib selection. Evaluation of trametinib-resistant cancer cells revealed activation of STAT3, FAK, and AKT signaling along with elevated S6 protein phosphorylation, which could be suppressed and resensitized to trametinib by combining with repotrectinib. Repotrectinib/trametinib combination in a syngeneic GEMM KRASG12D lung model had greater tumor growth inhibition than either single agent treatment. A similar combination efficacy benefit was observed in a HCT116 (CRC KRASG13D) xenograft model concomitant with suppression of SRC/FAK/STAT3/ERK activation. Taken together, repotrectinib combinations with MEK inhibitors demonstrated enhanced efficacy in both in vitro and in vivo preclinical models. Repotrectinib was shown to suppress molecular mechanisms of adaptive resistance mechanisms to MEK inhibition in preclinical models. These results suggest that the combination of repotrectinib with MEKi can repress the mutant KRAS signaling network to achieve more potent and durable anti-tumor activity and warrants clinical investigation in patients with KRASG12D and KRASG12V mutant cancers. Citation Format: Nathan V. Lee, Wei Deng, Dayong Zhai, Laura Rodon, Ana Parra, Jessica Cowell, Afsheen Banisadr, Xin Zhang, Brion W. Murray. Repotrectinib increases effectiveness of MEK inhibitors in KRAS mutant cancer models [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 1104.

Abstract 5710: Autophagy inhibition sensitizes Liver Kinase B1 (LKB1) - deficient Kras-driven lung tumors to MEK inhibitor Trametinib

Abstract Tumor suppressor liver kinase B1 (LKB1) activates 5'-adenosine monophosphate protein kinase (AMPK) and plays an essential role in maintaining energy homeostasis. LKB1 mutations are the third most frequent mutation detected in non-small cell lung cancer (NSCLC). Compared to p53 mutation, co-mutations in LKB1 with KRAS cause aggressive tumor growth, metastases and resistance to chemotherapy as well as immunotherapy. Thus, identifying a novel target to improve LKB1-deficient Kras-driven NSCLC treatment is urgently needed. Our previous work demonstrates that autophagy inhibition is synthetically lethal in KrasG12D/+;Lkb1−/− (KL) mediated tumorigenesis; in contrast to intact autophagy KL lung tumors, loss of an autophagy-essential gene Atg7 dramatically impaired tumor initiation and tumor growth. This is in sharp contrast to wild-type (WT) Lkb1 (KrasG12D/+;p53−/− (KP)) tumors that are less sensitive to autophagy gene ablation. These observations indicate that LKB1 mutations predispose KRAS NSCLC to autophagy inhibition and that LKB1 mutations could be explored as a predictive biomarker for precision lung cancer therapy. To further value our discoveries in clinical translational ability, we treated mouse lung tumor-derived cell lines (TDCLs) with FDA approved autophagy inhibitor hydroxychloroquine (HCQ) and found that KL TDCLs were much sensitive to HCQ-induced cell death compared with Lkb1-WT KP TDCLs. Furthermore, a combination treatment of HCQ with mitogen-activated protein kinase kinase (MAPKK or MEK) inhibitor Trametinib showed synergistic anti-proliferative effects in KL TDCLs, but not in KP TDCLs. To elucidate the underlying mechanism of increased sensitivity of KL TDCLs to Trametinib by autophagy ablation, we performed metabolomic profiling of KL TDCLs with Trametinib, HCQ alone or in combination treatment. We found that the levels of several glycolytic and TCA cycle intermediates, as well as amino acids, were significantly upregulated upon treatment with Trametinib, which were significantly reduced by the combined treatment with HCQ and trametinib. Moreover, Trametinib treatment led to an increased level of ATP, which was decreased by the combination treatment. Similarly, we observed anti-tumor synergistic effects of the combination treatment in KL allograft tumor growth. In addition, metastases of KL TDCLs to the lung was reduced by the combination treatment compared to the single agents. We further found that in KRAS-mutant human lung cancer cell lines, LKB1-mutant cells were much sensitive to the combination treatment than LKB1-WT cells. Our observations suggest that KL TDCLs and KL human lung cancer cells resist to Trametinib treatment by upregulating autophagy to maintain energy homeostasis for survival. Therefore, combination therapy of autophagy and MEK inhibition could be a novel therapeutic strategy to specifically treat LKB1-deficient NSCLC. Citation Format: Vrushank Dharmesh Bhatt, Khoosheh Khayati, Jerry Kong, Akash Raju, Zhixian Hu, Xiaoyang Su, Jessie Yanxiang Guo. Autophagy inhibition sensitizes Liver Kinase B1 (LKB1) - deficient Kras-driven lung tumors to MEK inhibitor Trametinib [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5710.

SREBP1 regulates mitochondrial metabolism in oncogenic KRAS expressing NSCLC.

Cancer cells require extensive metabolic reprograming in order to provide the bioenergetics and macromolecular precursors needed to sustain a malignant phenotype. Mutant KRAS is a driver oncogene that is well-known for its ability to regulate the ERK and PI3K signaling pathways. However, it is now appreciated that KRAS can promote the tumor growth via upregulation of anabolic metabolism. We recently reported that oncogenic KRAS promotes a gene expression program of de novo lipogenesis in non-small cell lung cancer (NSCLC). To define the mechanism(s) responsible, we focused on the lipogenic transcription factor SREBP1. We observed that KRAS increases SREBP1 expression and genetic knockdown of SREBP1 significantly inhibited the cell proliferation of mutant KRAS-expressing cells. Unexpectedly, lipogenesis was not significantly altered in cells subject to SREBP1 knockdown. Carbon tracing metabolic studies showed a significant decrease in oxidative phosphorylation and RNA-seq data revealed a significant decrease in mitochondrial encoded subunits of the electron transport chain (ETC). Taken together, these data support a novel role, distinct from lipogenesis, of SREBP1 on mitochondrial function in mutant KRAS NSCLC.