During G1-phase of the cell cycle, normal cells respond first to growth factors that indicate that it is appropriate to divide and then later in G1 to the presence of nutrients that indicate ...sufficient raw material to generate two daughter cells. Dividing cells rely on the “conditionally essential” amino acid glutamine (Q) as an anaplerotic carbon source for TCA cycle intermediates and as a nitrogen source for nucleotide biosynthesis. We previously reported that while non-transformed cells arrest in the latter portion of G1 upon Q deprivation, mutant KRas-driven cancer cells bypass the G1 checkpoint, and instead, arrest in S-phase. In this study, we report that the arrest of KRas-driven cancer cells in S-phase upon Q deprivation is due to the lack of deoxynucleotides needed for DNA synthesis. The lack of deoxynucleotides causes replicative stress leading to activation of the ataxia telangiectasia and Rad3-related protein (ATR)-mediated DNA damage pathway, which arrests cells in S-phase. The key metabolite generated from Q utilization was aspartate, which is generated from a transaminase reaction whereby Q-derived glutamate is converted to α-ketoglutarate with the concomitant conversion of oxaloacetate to aspartate. Aspartate is a critical metabolite for both purine and pyrimidine nucleotide biosynthesis. This study identifies the molecular basis for the S-phase arrest caused by Q deprivation in KRas-driven cancer cells that arrest in S-phase in response to Q deprivation. Given that arresting cells in S-phase sensitizes cells to apoptotic insult, this study suggests novel therapeutic approaches to KRas-driven cancers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A series of novel thieno2,3-dpyrimidine analogs were designed and synthesized as KRAS G12D inhibitors via combinatorial virtual screening approach. Most compounds exhibited potent antiproliferative ...activity on KRAS G12D mutated cancer cell lines (Panc1, SW1990 and CT26) with IC50 values in the low micromolar range. Among them, compound KD-8 showed the highest antiproliferative activity with an average IC50 of 2.1 μM against three KRAS G12D-mutated cells (Panc1, SW1990 and CT26). KD-8 decreased the active form of KRAS (KRAS-GTP) in KRAS G12D mutated cancer cell lines (CT26 and SW1990) but not in KRAS G13D mutated cancer cells (HCT116). Moreover, KD-8 down-regulated the phosphorylated Raf and Erk in CT26 and SW1990 cancer cell lines but not in HeLa cells (KRAS WT). The binding affinity of KD-8 was further confirmed by the isothermal titration calorimetry (ITC) assay in which KD-8 exhibited a KD of 33 nM for binding to KRAS G12D protein. In addition, KD-8 (40 mg/kg or 60 mg/kg) exhibited significant antitumor efficacy in a CT26 tumor model with a tumor growth inhibition (TGI) of 42% or 53% without causing apparent toxicity. Taken together the above results suggest that KD-8 is a promising KRAS G12D inhibitor deserving further investigation.
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●Novel thieno2,3-dpyrimidine-based KRAS G12D Inhibitors were discovered as anticancer agents.●KD-8 could bind to KRAS G12D protein with high affinity (KD = 33 nM by ITC).●KD-8 decreased the active form of KRAS G12D (KRAS G12D-GTP) but not KRAS G13D.●KD-8 suppressed CT26 tumor growth with a TGI of 42%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Despite the implementation of personalized medicine, patients with metastatic CRC (mCRC) still have a dismal overall survival due to the frequent occurrence of acquired resistance mechanisms thereby ...leading to clinical relapse. Understanding molecular mechanisms that support acquired resistance to anti-EGFR targeted therapy in mCRC is therefore clinically relevant and key to improving patient outcomes. Here, we observe distinct metabolic changes between cetuximab-resistant CRC cell populations, with in particular an increased glycolytic activity in KRAS-mutant cetuximab-resistant CRC cells (LIM1215 and OXCO2) but not in KRAS-amplified resistant DiFi cells. We show that cetuximab-resistant LIM1215 and OXCO2 cells have the capacity to recycle glycolysis-derived lactate to sustain their growth capacity. This is associated with an upregulation of the lactate importer MCT1 at both transcript and protein levels. Pharmacological inhibition of MCT1, with AR-C155858, reduces the uptake and oxidation of lactate and impairs growth capacity in cetuximab-resistant LIM1215 cells both in vitro and in vivo. This study identifies MCT1-dependent lactate utilization as a clinically actionable, metabolic vulnerability to overcome KRAS-mutant-mediated acquired resistance to anti-EGFR therapy in CRC.
•Acquired resistance to cetuximab is associated with metabolic alterations in CRC cells.•Lactate utilization is a metabolic vulnerability in KRAS-mutant resistant CRC cells.•MCT1 overexpression sustains lactate recycling in KRAS-mutant resistant CRC cells.•Inhibition of MCT1 transporter activity overcomes cetuximab resistance in CRC cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Series of coumarin-based KRAS-G12C inhibitors were found through Virtual Screening and Rational Structural Optimization.•K45 displayed potent activity and selectivity against KRAS ...mutant cells.•K45 inhibited active KRAS, p-ERK and p-AKT in KRAS-G12C mutant cells.•K45 induced apoptosis by increasing the expression BAD and BAX in H23 cells.
KRAS-G12C inhibitors has been made significant progress in the treatment of KRAS-G12C mutant cancers, but their clinical application is limited due to the adaptive resistance, motivating development of novel structural inhibitors. Herein, series of coumarin derivatives as KRAS-G12C inhibitors were found through virtual screening and rational structural optimization. Especially, K45 exhibited strong antiproliferative potency on NCI-H23 and NCI-H358 cancer cells harboring KRAS-G12C with the IC50 values of 0.77 μM and 1.50 μM, which was 15 and 11 times as potent as positive drug ARS1620, respectively. Furthermore, K45 reduced the phosphorylation of KRAS downstream effectors ERK and AKT by reducing the active form of KRAS (KRAS GTP) in NCI-H23 cells. In addition, K45 induced cell apoptosis by increasing the expression of anti-apoptotic protein BAD and BAX in NCI-H23 cells. Docking studies displayed that the 3-naphthylmethoxy moiety of K45 extended into the cryptic pocket formed by the residues Gln99 and Val9, which enhanced the interaction with the KRAS-G12C protein. These results indicated that K45 was a potent KRAS-G12C inhibitor worthy of further study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Immunotherapy has improved the clinical outcomes of patients with advanced non-small cell lung cancer (NSCLC). However, in patients with Kirsten rat sarcoma viral oncogene homolog (
) mutations, the ...superior efficacy of immunotherapy has not been elucidated and especially in real-world practice. Our study aimed to use real-world data to assess the efficacy of immunotherapy in
-mutant NSCLC in a Chinese cohort.
In this retrospective cohort study, we extracted the clinical, molecular, and pathologic data from the electronic health records of patients with advanced
-mutant NSCLC at Shandong Cancer Hospital between January 2018 and May 2022. Furthermore, we evaluated the progression-free survival (PFS) and overall survival (OS) of the included patients.
Between January 2018 and November 2020, 793 patients were identified with stage IIIB-IV NSCLC and a total of 122 patients with
mutations were included in the analysis. The majority of patients were diagnosed with stage IV (82.0%) adenocarcinoma (93.4%), along with a history of smoking (57.4%). Of these, 42% of patients received anti-PD-(L)1 with or without chemotherapy (Immunotherapy-based regimens), while 58.2% of patients received chemotherapy (Chemotherapy-based regimens). The median overall survival (mOS) in this cohort was 22.9 months (95% CI: 14.1-31.7), while the median-progression-free survival (mPFS) was 9.4 months (95% CI: 6.6-12.1). Patients receiving immunotherapy-based regimens displayed better mOS than those receiving chemotherapy-based regimens (45.2 vs. 11.3 months;
=1.81E-05), with no statistical difference observed in the mPFS (10.5 vs. 8.2 months;
=0.706). Patients receiving immunotherapy-based regimens either in the first line (
=0.00038,
=0.010, respectively) or second-line setting (
=0.010,
=0.026, respectively) showed benefits in both PFS and OS. Subgroup analysis indicated that in patients having
G12C or non-
G12C mutant types, immunotherapy showed benefits of better OS (
=0.0037,
=0.020, respectively) than chemotherapy. Moreover, in advanced NSCLCs patients with or without
co-mutation the immunotherapy-based regimen achieved longer OS and PFS than chemotherapy-based regimens.
In the Chinese population of patients with
-mutant advanced NSCLC, immunotherapy-based regimens achieved longer OS than chemotherapy-based regimens, which was independent of first or second-line setting, as well as
mutational subtypes.
KRAS plays a crucial role in regulating cell survival and proliferation and is one of the most commonly mutated oncogenes in human cancers. The novel KRASG12D inhibitor, MRTX1133, demonstrates ...promising antitumor efficacy in vitro and in vivo. However, the development of acquired resistance in treated patients presents a considerable challenge to sustained therapeutic effectiveness. In response to this challenge, we conducted site-specific mutagenesis screening to identify potential secondary mutations that could induce resistance to MRTX1133. We screened a range of KRASG12D variants harboring potential secondary mutations, and 44 representative variants were selected for in-depth validation of the pooled screening outcomes. We identified eight variants (G12D with V9E, V9W, V9Q, G13P, T58Y, R68G, Y96W, and Q99L) that exhibited substantial resistance, with V9W showing notable resistance, and downstream signaling analyses and structural modeling were conducted. We observed that secondary mutations in KRASG12D can lead to acquired resistance to MRTX1133 and BI-2865, a novel pan-KRAS inhibitor, in human cancer cell lines. This evidence is critical for devising new strategies to counteract resistance mechanisms and, ultimately, enhance treatment outcomes in patients with KRASG12D-mutant cancers.
•Secondary mutation in KRASG12D induces resistance to MRTX1133.•Site-specific mutagenesis screening identifies resistance-conferring variants.•The V9W mutation in KRASG12D shows significant resistance.•Downstream signaling analyses and structural modeling were utilized.•These insights aid in devising strategies against acquired resistance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cancer research involves significant animal consumption and suffering. Tumor cells can be differentiated in vitro into three-dimensional organoids that resemble the primary tumor. In basic cancer ...research, however, tumor organoids are usually only used alongside animal experiments. We have established an easy-to-perform protocol that allows to culture KRAS-driven lung tumor cells as organoids for extended periods of time. Like the corresponding tumors in mice, the organoids produce surfactant protein C but no markers of airway epithelial cells (e.g. SCGB1A1, KRT5). The organoids can be passaged as single cell suspensions. Our organoid model contributes to replace animal experiments with cell culture systems and can be used for drug testing or functional studies in cancer research.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) is the most frequently mutated oncogene in human cancers with mutations predominantly occurring in codon 12. These mutations disrupt the normal ...function of KRAS by interfering with GTP hydrolysis and nucleotide exchange activity, making it prone to the GTP-bound active state, thus leading to sustained activation of downstream pathways. Despite decades of research, there has been no progress in the KRAS drug discovery until the groundbreaking discovery of covalently targeting the KRAS
mutation in 2013, which led to revolutionary changes in KRAS-targeted therapy. So far, two small molecule inhibitors sotorasib and adagrasib targeting KRAS
have received accelerated approval for the treatment of non-small cell lung cancer (NSCLC) harboring KRAS
mutations. In recent years, rapid progress has been achieved in the KRAS-targeted therapy field, especially the exploration of KRAS
covalent inhibitors in other KRAS
-positive malignancies, novel KRAS inhibitors beyond KRAS
mutation or pan-KRAS inhibitors, and approaches to indirectly targeting KRAS. In this review, we provide a comprehensive overview of the molecular and mutational characteristics of KRAS and summarize the development and current status of covalent inhibitors targeting the KRAS
mutation. We also discuss emerging promising KRAS-targeted therapeutic strategies, with a focus on mutation-specific and direct pan-KRAS inhibitors and indirect KRAS inhibitors through targeting the RAS activation-associated proteins Src homology-2 domain-containing phosphatase 2 (SHP2) and son of sevenless homolog 1 (SOS1), and shed light on current challenges and opportunities for drug discovery in this field.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
G12D mutation is the most common KRAS mutation detected in carcinomas.G12D mutation confers a unique structural conformation that influences downstream signaling and may lead to its potent oncogenic ...activity.Invasive mucinous adenocarcinoma of the lung displays histological features of gastrointestinal cancers and a predominance of KRAS-G12D mutations.Adenocarcinomas of the lung, pancreas and colon driven by KRAS-G12D mutation display an immunosuppressive tumor microenvironment.Mutations in tumor suppressor genes found to co-occur with KRAS-G12D influence tumor biology and response to therapy.KRAS-G12D inhibitors may need to be tailored according to tissue of origin and considered in the context of the co-mutational genomic landscape.
KRAS is the most frequently mutated oncogene in cancer. Activating mutations in codon 12, especially G12D, have the highest prevalence across a range of carcinomas and adenocarcinomas. With inhibitors to KRAS-G12D now entering clinical trials, understanding the biology of KRAS-G12D cancers, and identifying biomarkers that predict therapeutic response is crucial. In this Review, we discuss the genomics and biology of KRAS-G12D adenocarcinomas, including histological features, transcriptional landscape, the immune microenvironment, and how these factors influence response to therapy. Moreover, we explore potential therapeutic strategies using novel G12D inhibitors, leveraging knowledge gained from clinical trials using G12C inhibitors.
KRAS is the most frequently mutated oncogene in cancer. Activating mutations in codon 12, especially G12D, have the highest prevalence across a range of carcinomas and adenocarcinomas. With inhibitors to KRAS-G12D now entering clinical trials, understanding the biology of KRAS-G12D cancers, and identifying biomarkers that predict therapeutic response is crucial. In this Review, we discuss the genomics and biology of KRAS-G12D adenocarcinomas, including histological features, transcriptional landscape, the immune microenvironment, and how these factors influence response to therapy. Moreover, we explore potential therapeutic strategies using novel G12D inhibitors, leveraging knowledge gained from clinical trials using G12C inhibitors.
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