KRAS G12D can be targeted by potent salt-bridge forming inhibitors

KRAS mutation occurs in nearly 30% of human cancers, yet the most prevalent and oncogenic KRAS mutation (G12D) still lacks inhibitors. Herein, we explored the formation of a salt-bridge between KRAS's Asp12 residue and a series of potent inhibitors. Our ITC results show that these inhibitors bind to and inhibit both GDP-bound and GTP-bound KRAS G12D, and our crystallographic studies revealed the structural basis of inhibitor binding in the switch-II pocket, experimentally confirming the formation of a salt-bridge between the piperazine moiety of the inhibitors and the 12D residue of the mutant protein. Among KRAS family proteins and mutants, both ITC and enzymatic assays support the selectivity of the inhibitors for KRAS G12D, and the inhibitors disrupt the KRAS-CRAF interaction. We also observed inhibition of cancer cell proliferation and inhibition of MAPK signaling by a representative inhibitor (TH-Z835); however, since this was not fully dependent on KRAS mutation status, it is possible that our inhibitors may have off-target effects via non-KRAS small GTPases. Experiments with a mouse model of pancreatic cancer showed that TH-Z835 significantly reduced tumor volume and synergized with an anti-PD-1 antibody. Collectively, our study demonstrates proof-of-concept for a salt-bridge, induced-fit pocket strategy for KRAS G12D, which warrants future medicinal chemistry efforts for optimal efficacy and minimized off-target effects.

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Relation of EGFR and KRAS mutation status with phosphorylation of EGFR in lung adenocarcinomas

10.26226/morressier.578f37fbd462b8028d89029c ◽

2016 ◽

Author(s):

Luka Brcic

Keyword(s):

Kras Mutation ◽

Mutation Status ◽

Lung Adenocarcinomas ◽

Kras Mutation Status

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Discordance of KRAS Mutational Status between Primary Tumors and Liver Metastases in Colorectal Cancer: Impact on Long-Term Survival Following Radical Resection

Cancers ◽

10.3390/cancers13092148 ◽

2021 ◽

Vol 13 (9) ◽

pp. 2148

Author(s):

Francesco Ardito ◽

Francesco Razionale ◽

Lisa Salvatore ◽

Tonia Cenci ◽

Maria Vellone ◽

...

Keyword(s):

Colorectal Cancer ◽

Liver Metastases ◽

Primary Tumor ◽

Kras Mutation ◽

Colorectal Tumor ◽

Term Survival ◽

Primary Tumors ◽

Mutation Status ◽

Primary Colorectal Tumor ◽

Kras Mutation Status

If KRAS mutation status of primary colorectal tumor is representative of corresponding colorectal liver metastases (CRLM) mutational pattern, is controversial. Several studies have reported different rates of KRAS discordance, ranging from 4 to 32%. Aim of this study is to assess the incidence of discordance and its impact on overall survival (OS) in a homogenous group of patients. KRAS mutation status was evaluated in 107 patients resected for both primary colorectal tumor and corresponding CRLM at the same institution, between 2007 and 2018. Discordance rate was 15.9%. Its incidence varied according to the time interval between the two mutation analyses (p = 0.025; Pearson correlation = 0.2) and it was significantly higher during the first 6 months from the time of primary tumor evaluation. On multivariable analysis, type of discordance (wild-type in primary tumor, mutation in CRLM) was the strongest predictor of poor OS (p < 0.001). At multivariable logistic regression analysis, the number of CRLM >3 was an independent risk factor for the risk of KRAS discordance associated with the worst prognosis (OR = 4.600; p = 0.047). Results of our study suggested that, in the era of precision medicine, possibility of KRAS discordance should be taken into account within multidisciplinary management of patients with metastatic colorectal cancer.

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HIV-1 Tat Regulates Endothelial Cell Cycle Progression via Activation of the Ras/ERK MAPK Signaling Pathway

Molecular Biology of the Cell ◽

10.1091/mbc.e05-08-0717 ◽

2006 ◽

Vol 17 (4) ◽

pp. 1985-1994 ◽

Cited By ~ 47

Author(s):

Elena Toschi ◽

Ilaria Bacigalupo ◽

Raffaele Strippoli ◽

Chiara Chiozzini ◽

Anna Cereseto ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Kaposi's Sarcoma ◽

Cell Cycle Progression ◽

Kaposi’S Sarcoma ◽

Mapk Signaling ◽

Small Gtpases ◽

Mitogen Activated Protein Kinase ◽

Endothelial Cell Proliferation ◽

Hiv 1

Tat, the transactivator of HIV-1 gene expression, is released by acutely HIV-1-infected T-cells and promotes adhesion, migration, and growth of inflammatory cytokine-activated endothelial and Kaposi's sarcoma cells. It has been previously demonstrated that these effects of Tat are due to its ability to bind through its arginine-glycine-aspartic (RGD) region to the α5β1 and αvβ3 integrins. However, the signaling pathways linking Tat to the regulation of cellular functions are incompletely understood. Here, we report that Tat ligation on human endothelial cells results in the activation of the small GTPases Ras and Rac and the mitogen-activated protein kinase ERK, specifically through its RGD region. In addition, we demonstrated that Tat activation of Ras, but not of Rac, induces ERK phosphorylation. We also found that the receptor proximal events accompanying Tat-induced Ras activation are mediated by tyrosine phosphorylation of Shc and recruitment of Grb2. Moreover, Tat enabled endothelial cells to progress through the G1 phase in response to bFGF, and the process is linked to ERK activation. Taken together, these data provide novel evidence about the ability of Tat to activate the Ras-ERK cascade which may be relevant for endothelial cell proliferation and for Kaposi's sarcoma progression.

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Detection and recovery of circulating colon cancer cells using a dielectrophoresis-based device: KRAS mutation status in pure CTCs

Cancer Letters ◽

10.1016/j.canlet.2013.02.015 ◽

2013 ◽

Vol 335 (1) ◽

pp. 225-231 ◽

Cited By ~ 157

Author(s):

Francesco Fabbri ◽

Silvia Carloni ◽

Wainer Zoli ◽

Paola Ulivi ◽

Giulia Gallerani ◽

...

Keyword(s):

Colon Cancer ◽

Cancer Cells ◽

Kras Mutation ◽

Colon Cancer Cells ◽

Mutation Status ◽

Kras Mutation Status

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Racial disparity in KRAS mutation frequency and outcomes in colorectal cancer (CRC): A U.S. population based study.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.3_suppl.18 ◽

2021 ◽

Vol 39 (3_suppl) ◽

pp. 18-18

Author(s):

Jeffrey Bien ◽

Mayada Aljehani ◽

Jerry S.H. Lee ◽

Albert Y. Lin

Keyword(s):

Racial Disparity ◽

Kras Mutation ◽

Mutation Frequency ◽

Population Based ◽

Mutation Status ◽

Risk Increase ◽

Kras Status ◽

Significant Difference ◽

Hispanic Patients ◽

Race Ethnicity

18 Background: Racial disparity in CRC survival outcome is well documented. Although the reasons for disparity are unclear, a combination of differences in access to care, quality of care, differential treatment response, and underlying cancer biology are implicated. Further, recent studies have observed differences in KRAS mutation frequency between race/ethnic groups. KRAS mutation in metastatic CRC portends a worse response to EGFR-directed therapy, and predicts a poorer prognosis. In this study, we examined whether racial/ethnic differences in KRAS mutation frequency might impact CRC outcomes on a population-based level. Methods: We examined data from 202,237 CRC patients in the Surveillance, Epidemiology, and End Results (SEER) registry between 2010 and 2015. The differences in tumor mutation status by stage and race/ethnicity were examined by χ2 testing. Cause-specific survival (CSS) and overall survival by mutation status were plotted by Kaplan-Meir curves. A multivariable Cox-proportional hazards model was used to construct hazard ratios and 95% confidence intervals (CI) using patient demographics, tumor characteristics, and KRAS mutation status. Results: Overall, about 9% of patients (n = 18,248) in the SEER registry had KRAS status available. In this cohort, tumors from Non-Hispanic Black (NHB) (48%) or Hispanic patients (44%) carried a greater KRAS mutation (mKRAS) rate when compared against Non-Hispanic White (NHW) (39%) or Asian or Pacific Islander (API) patients (37%) (p < 0.01). The assessment of the impact of mKRAS within each race/ethnic group, comparing patients with mKRAS versus wild-type KRAS (wKRAS) on CSS risk show a 7% risk increase for NHW, (HR = 1.07; 95%CI:1.02-1.12), a 15% risk increase for NHB, (HR = 1.15; 95%CI:1.04-1.26) and no significant increase among API, (HR = 1.02; 95%CI:0.92-1.4). Among patients with wKRAS, with NHW for reference, the risk of CSS is 11% higher among NHB (HR = 1.11; 95%CI:1.00-1.23), 14% higher for Hispanic, (HR = 1.14; 95%CI:1.02-1.26) and no significant difference observed among API, (HR = 1.03; 95%CI:0.91-1.16). Evaluation of the interaction between race/ethnicity and KRAS status on the CSS risk shows an increase of: 11% for mKRAS NHW, (HR = 1.11; 95%CI:1.00-1.23), 13% risk for NHB (HR = 1.13; 95%CI:1.01-1.25), 11% for Hispanic wKRAS, (HR = 1.11; 95%CI:1.04-1.18), 31% for Hispanic mKRAS (HR = 1.31; 95%CI:1.18-1.145), 16% for wKRAS API (HR = 1.16; 95%CI:1.03-1.29). In contrast, no significant difference in risk is seen for NHB nor API patients, HR = 1.02 (95%CI:0.90-1.14) and 1.04 (95%CI:0.91-1.20) respectively. Conclusions: mKRAS, compared to wKRAS, connotes worse CSS among NHW and NHB patients. Among wKRAS, NHB and Hispanic patients still experience higher mortality risk. This data suggests the negative prognosis heretofore associated with mKRAS may be linked to race/ethnicity and worthy of further study.

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ESDR054 - Machine learning prediction of filaggrin mutation status from palmar images: a proof-of-concept study

10.26226/morressier.61081ff8bc981037240fe3bf ◽

2021 ◽

Author(s):

Lloyd Steele

Keyword(s):

Machine Learning ◽

Proof Of Concept ◽

Mutation Status ◽

Concept Study

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Conserved charged residues in the leucine-rich repeat domain of the Ran GTPase activating protein are required for Ran binding and GTPase activation

Biochemical Journal ◽

10.1042/bj3430653 ◽

1999 ◽

Vol 343 (3) ◽

pp. 653-662 ◽

Cited By ~ 12

Author(s):

Jörg HABERLAND ◽

Volker GERKE

Keyword(s):

Nucleocytoplasmic Transport ◽

Small Gtpases ◽

Structural Basis ◽

Ran Gtpase ◽

Protein Protein Interaction ◽

Charged Residues ◽

Gtpase Activation ◽

Gtpase Cycle ◽

Leucine Rich Repeats ◽

Lrr Domain

GTPase activating proteins (GAPs) for Ran, a Ras-related GTPase participating in nucleocytoplasmic transport, have been identified in different species ranging from yeast to man. All RanGAPs are characterized by a conserved domain consisting of eight leucine-rich repeats (LRRs) interrupted at two positions by so-called separating regions, the latter being unique for RanGAPs within the family of LRR proteins. The cytosolic RanGAP activity is essential for the Ran GTPase cycle which in turn provides directionality in nucleocytoplasmic transport, but the structural basis for the interaction between Ran and its GAP has not been elucidated. In order to gain a better understanding of this interaction we generated a number of mutant RanGAPs carrying amino acid substitutions in the LRR domain and analysed their complex formation with Ran as well as their ability to stimulate the intrinsic GTPase activity of the G protein. We show that conserved charged residues present in the separating regions of the LRR domain are indispensable for efficient Ran binding and GAP activity. These separating regions contain three conserved arginines which could possibly serve as catalytic residues similar to the arginine fingers identified in GAPs for other small GTPases. However, mutations in two of these arginines do not affect the GAP activity and replacement of the third conserved arginine (Arg91 in human RanGAP) severely interferes not only with GAP activity but also with Ran binding. This indicates that RanGAP-stimulated GTP hydrolysis on Ran does not involve a catalytic arginine residue but requires certain charged residues of the LRR domain of the GAP for mediating the protein-protein interaction.

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Ανίχνευση μεταλλάξεων του EGFR και KRAS σε ασθενείς με μη-μικροκυτταρικό καρκίνο του πνεύμονα και διερεύνηση της αξίας τους ως προβλεπτικών παραγόντων ανταπόκρισης στη θεραπεία

10.12681/eadd/37962 ◽

2013 ◽

Author(s):

Αριστέα Καλυκάκη

Keyword(s):

Kras Mutation ◽

Smoking History ◽

Egfr Mutations ◽

Front Line ◽

Kras Mutations ◽

Primary Tumors ◽

Mutation Status ◽

Kras Mutation Status ◽

Line Chemotherapy ◽

Exon 19

The purpose of this study was to investigate whether the EGFR and KRASmutation status are predictive factors for Greeks patients with NSCLC. Initially, wecalculated the rate and the pattern of EGFR and KRAS mutations in 639 patients withNSCLC and then we correlated the mutations status with clinicopathologicalcharacteristics, the response to 1st line chemotherapy and patients’ overall survival.We also investigated the association of EGFR mutations with the EGFR geneamplification. Finally, in a group of 25 patients the mutation status of these genes inthe primary tumors and the corresponding metastasis was evaluated.The genetic analysis performed in FFPE tissue samples of primary tumor ormetastasis. DNA was extracted using universal techniques. For mutation analysis exons18, 19, 20 and 21 of the EGFR and exon 2 of KRAS genes were sequentially amplified bypolymerase chain reaction (PCR) and subjected to direct sequencing. Finally, EGFRamplification was determined by quantitative real time PCR.Analysis of EGFR mutations was successful performed in 634 patients andmutations were detected in 100 (15.8%) of them. Activating mutations were detected in 8.4%. The most common mutations were deletions of 4-5 codons in exon 19 (del 19,71.7%, 38/53) and the missense mutation at position 858 (L858R) in exon 21 (22.6%,12/53). Also in 47 (7.4%) patients other mutations were detected in four exons ofEGFR, which have been reported previously or are new. We found that the incidenceof EGFR mutations was statistically significant in women with no smoking history andwith adenocarcinoma histology.The mutation analysis of the KRAS gene was successfully performed on 399patients and mutations detected in 20.8% of them (83/399). Especially, 92.8% of themutations were found at codon 12 and 7.2% at codon 13. KRAS mutations weresignificantly associated with smoking history with higher incidence in smokers thannonsmokers. There was also a significant association between KRAS mutations andadenocarcinoma histology.The predictive value of EGFR and KRAS mutations was examined in a subgroupof patients (n=162) with NSCLC who received chemotherapy as 1st line therapy.Patients with classical EGFR mutations had a higher probability of response (55.6%) to front-line chemotherapy as compared to those with wild type EGFR (21.8%) (p =0.023). Multivariate analysis revealed the 'classical' activating EGFR mutations as anindependent predictive factor for response to 1st line chemotherapy. There was nosignificant correlation between the EGFR or KRAS mutation status and the time totumor progression. The presence of activating EGFR but not of KRAS mutations wasassociated with a significantly higher overall survival compared to patients withoutmutations treated with platinum-based front-line chemotherapy.Epidermal growth factor receptor and KRAS mutation status was differentbetween primary tumors and corresponding metastases in 7 (28%) and 6 (24%) of the25 patients, respectively. This discrepancy was not statistically significant with theMcNemar’s test.EGFR amplification was found in 7.2% (6/83) of primary tumors. Among thepatients with EGFR gene amplification none carried KRAS mutations while 2 had EGFR exon 19 deletion.

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Prognostic impact of K-RAS mutational status and primary tumor location in patients undergoing resection for colorectal cancer liver metastases: an update

Future Oncology ◽

10.2217/fon-2019-0196 ◽

2019 ◽

Vol 15 (27) ◽

pp. 3149-3157

Author(s):

Juan M O´Connor ◽

Fernando Sanchez Loria ◽

Victoria Ardiles ◽

Jorge Grondona ◽

Pablo Sanchez ◽

...

Keyword(s):

Liver Metastases ◽

Primary Tumor ◽

Kras Mutation ◽

Tumor Location ◽

Prognostic Impact ◽

Recurrence Free Survival ◽

Mutation Status ◽

Free Survival ◽

Primary Tumor Location ◽

Kras Mutation Status

Aim: To determine the impact of KRAS mutation status on survival in patients undergoing surgery for colorectal liver metastases (CLM). Patients & methods: Patients with resected CLM and KRAS mutations. Survival was compared between mt-KRAS and wt-KRAS. Results: Of 662 patients, 174 (26.3%) were mt-KRAS and 488 (73.7%) wt-KRAS. mt-KRAS patients had significantly lower recurrence-free survival (HR: 1.42; 95% CI: 1.10–1.84). There were no differences between the groups for sidedness. Poorer survival was associated with mt-KRAS with positive lymph nodes, >1 metastases, tumors >5 cm, synchronous tumors and R1–R2. Conclusion: KRAS mutation status can help predict recurrence-free survival. Primary tumor location was not a prognostic factor after resection. KRAS mutation status can help design a multidisciplinary approach after curative resection of CLM.

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