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Kras g12c

Xiaozhou Li, Tianyue Yang, Caesar Siqi Li, Youtao Song, Hong Lou, Dagang Guan, Lili Jin
In this paper, we discuss the use of a procedure based on polymerase chain reaction (PCR) and surface enhanced Raman spectroscopy (SERS) (PCR-SERS) to detect DNA mutations. Methods: This method was implemented by first amplifying DNA-containing target mutations, then by annealing probes, and finally by applying SERS detection. The obtained SERS spectra were from a mixture of fluorescence tags labeled to complementary sequences on the mutant DNA. Then, the SERS spectra of multiple tags were decomposed to component tag spectra by multiple linear regression (MLR)...
2018: Theranostics
Edward C Stites, Andrey S Shaw
KRAS has proven difficult to target pharmacologically. Two strategies have recently been described for covalently targeting the most common KRAS mutant in lung cancer, KRAS G12C. Previously, we developed a computational model of the processes that regulate Ras activation. Here, we use this model to investigate KRAS G12C covalent inhibitors. We updated the model to include Ras protein turnover, and validation demonstrates that our model performs well in areas of G12C targeting where conventional wisdom struggles...
February 27, 2018: CPT: Pharmacometrics & Systems Pharmacology
Vincent L Cannataro, Stephen G Gaffney, Carly Stender, Zi-Ming Zhao, Mark Philips, Andrew E Greenstein, Jeffrey P Townsend
Activating mutations in RAS genes are associated with approximately 20% of all human cancers. New targeted therapies show preclinical promise in inhibiting the KRAS G12C variant. However, concerns exist regarding the effectiveness of such therapies in vivo given the possibilities of existing intratumor heterogeneity or de novo mutation leading to treatment resistance. We performed deep sequencing of 27 KRAS G12-positive lung tumors to determine the prevalence of other oncogenic mutations within KRAS or within commonly mutated downstream genes that could confer resistance at the time of treatment...
February 16, 2018: Oncogene
G A Yanus, T A Akhapkina, A O Ivantsov, E V Preobrazhenskaya, S N Aleksakhina, I V Bizin, A P Sokolenko, N V Mitiushkina, E Sh Kuligina, E N Suspitsin, A R Venina, M M Holmatov, O A Zaitseva, O S Yatsuk, D V Pashkov, A M Belyaev, A V Togo, E N Imyanitov, A G Iyevleva
Distribution of cancer-predisposing mutations demonstrates significant interethnic variations. This study aimed to evaluate patterns of APC and MUTYH germ-line mutations in Russian patients with colorectal malignancies. APC gene defects were identified in 26/38 (68%) subjects with colon polyposis; 8/26 (31%) APC mutations were associated with 2 known mutational hotspots (p.E1309Dfs*4 [n = 5] and p.Q1062fs* [n = 3]), while 6/26 (23%) mutations were novel (p.K73Nfs*6, p.S254Hfs*12, p.S1072Kfs*9, p.E1547Kfs*11, p...
February 6, 2018: Clinical Genetics
Matthew R Janes, Jingchuan Zhang, Lian-Sheng Li, Rasmus Hansen, Ulf Peters, Xin Guo, Yuching Chen, Anjali Babbar, Sarah J Firdaus, Levan Darjania, Jun Feng, Jeffrey H Chen, Shuangwei Li, Shisheng Li, Yun O Long, Carol Thach, Yuan Liu, Ata Zarieh, Tess Ely, Jeff M Kucharski, Linda V Kessler, Tao Wu, Ke Yu, Yi Wang, Yvonne Yao, Xiaohu Deng, Patrick P Zarrinkar, Dirk Brehmer, Dashyant Dhanak, Matthew V Lorenzi, Dana Hu-Lowe, Matthew P Patricelli, Pingda Ren, Yi Liu
KRASG12C was recently identified to be potentially druggable by allele-specific covalent targeting of Cys-12 in vicinity to an inducible allosteric switch II pocket (S-IIP). Success of this approach requires active cycling of KRASG12C between its active-GTP and inactive-GDP conformations as accessibility of the S-IIP is restricted only to the GDP-bound state. This strategy proved feasible for inhibiting mutant KRAS in vitro; however, it is uncertain whether this approach would translate to in vivo. Here, we describe structure-based design and identification of ARS-1620, a covalent compound with high potency and selectivity for KRASG12C ...
January 25, 2018: Cell
Hiu Yeung Lau, Mei Wang
Mutant RAS isoforms are the most common oncogenes affecting human cancers. After decades of effort in developing drugs targeting oncogenic RAS-driven cancers, we are still charting an unclear path. Despite recent developments exemplified by KRAS (G12C) inhibitors, direct targeting of mutant RAS remains a difficult endeavor. Inhibiting RAS function by targeting its post-translational prenylation processing has remained an important approach, especially with recent progress on the study of isoprenylcysteine carboxylmethyltransferase (ICMT), the unique enzyme for the last step of prenylation processing of RAS isoforms and other substrates...
December 20, 2017: Small GTPases
Yijun Jia, Tao Jiang, Xuefei Li, Chao Zhao, Limin Zhang, Sha Zhao, Xiaozhen Liu, Meng Qiao, Jiawei Luo, Jinpeng Shi, Hui Yang, Yan Wang, Lei Xi, Shijia Zhang, Guanghui Gao, Chunxia Su, Shengxiang Ren, Caicun Zhou
We performed this retrospective study to investigate whether the KRAS mutation status and its subtypes could predict the effect of first-line platinum-based chemotherapy in Chinese patients with non-small cell lung cancer (NSCLC). Patients received who had KRAS mutations were enrolled. Correlations between KRAS mutations, specific mutant subtypes and responses to chemotherapy were analyzed using Kaplan-Meier and Cox proportional hazard methods. A total of 2,183 cases who received KRAS mutation detection were included...
December 2017: Oncology Letters
Irene Brana, Nhu-An Pham, Lucia Kim, Shingo Sakashita, Ming Li, Christine Ng, Yuhui Wang, Peter Loparco, Rafael Sierra, Lisa Wang, Blaise A Clarke, Benjamin G Neel, Lillian L Siu, Ming-Sound Tsao
PTEN inactivation occurs commonly in human cancers and putatively activates the PI3K/AKT/ mTOR pathway. Activation of this pathway has been involved in resistance to chemotherapy or anti-EGFR/HER2 therapies. We evaluated the combination of PI3K-mTOR inhibitors with chemotherapy or the pan-HER inhibitor dacomitinib in PTEN-deficient patient-derived tumor xenografts (PDX). Three PDXs were selected for their lack of PTEN expression by immunohistochemistry: a triple-negative breast cancer (TNBC), a KRAS G12R low-grade serous ovarian cancer (LGSOC), and KRAS G12C and TP53 R181P lung adenocarcinoma (LADC)...
October 17, 2017: Oncotarget
Pilar Garrido, María Eugenia Olmedo, Ana Gómez, Luis Paz Ares, Fernando López-Ríos, Juan Manuel Rosa-Rosa, José Palacios
KRAS mutations represent one of the most prevalent oncogenic driver mutations in non-small cell lung cancer (NSCLC). For many years we have unsuccessfully addressed KRAS mutation as a unique disease. The recent widespread use of comprehensive genomic profiling has identified different subgroups with prognostic implications. Moreover, recent data recognizing the distinct biology and therapeutic vulnerabilities of different KRAS subgroups have allowed us to explore different treatment approaches. Small molecules that selectively inhibit KRAS G12C or use of immune checkpoint inhibitors based on co-mutation status are some examples which anticipate that personalized treatment for this challenging disease is finally on the horizon...
September 2017: Therapeutic Advances in Medical Oncology
James L Sherwood, Helen Brown, Alessandro Rettino, Amelie Schreieck, Graeme Clark, Bart Claes, Bhuwnesh Agrawal, Ria Chaston, Benjamin S G Kong, Paul Choppa, Anders O H Nygren, Ina L Deras, Alexander Kohlmann
INTRODUCTION: This study assessed KRAS mutation detection and functional characteristics across 13 distinct technologies and assays available in clinical practice, in a blinded manner. METHODS: Five distinct KRAS-mutant cell lines were used to study five clinically relevant KRAS mutations: p.G12C, p.G12D, p.G12V, p.G13D and p.Q61H. 50 cell line admixtures with low (50 and 100) mutant KRAS allele copies at 20%, 10%, 5%, 1% and 0.5% frequency were processed using quantitative PCR (qPCR) (n=3), matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF) (n=2), next-generation sequencing (NGS) (n=6), digital PCR (n=1) and Sanger capillary sequencing (n=1) assays...
2017: ESMO Open
A Martinez-Marti, E Felip, J Matito, E Mereu, A Navarro, S Cedrés, N Pardo, A Martinez de Castro, J Remon, J M Miquel, A Guillaumet-Adkins, E Nadal, G Rodriguez-Esteban, O Arqués, R Fasani, P Nuciforo, H Heyn, A Villanueva, H G Palmer, A Vivancos
Background: Third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as osimertinib are the last line of targeted treatment of metastatic non-small-cell lung cancer (NSCLC) EGFR-mutant harboring T790M. Different mechanisms of acquired resistance to third-generation EGFR-TKIs have been proposed. It is therefore crucial to identify new and effective strategies to overcome successive acquired mechanisms of resistance. Methods: For Amplicon-seq analysis, samples from the index patient (primary and metastasis lesions at different timepoints) as well as the patient-derived orthotopic xenograft tumors corresponding to the different treatment arms were used...
October 1, 2017: Annals of Oncology: Official Journal of the European Society for Medical Oncology
Diána Brauswetter, Bianka Gurbi, Attila Varga, Edit Várkondi, Richárd Schwab, Gábor Bánhegyi, Orsolya Fábián, György Kéri, István Vályi-Nagy, István Peták
Pancreatic cancer is an increasing cause of cancer related death worldwide. KRAS is the dominant oncogene in this cancer type and molecular rationale would indicate, that inhibitors of the downstream target MEK could be appropriate targeted agents, but clinical trials have failed so far to achieve statistically significant benefit in unselected patients. We aimed to identify predictive molecular biomarkers that can help to define subgroups where MEK inhibitors might be beneficial alone or in combination. Next-generation sequencing data of 50 genes in three pancreatic cancer cell lines (MiaPaCa2, BxPC3 and Panc1) were analyzed and compared to the molecular profile of 138 clinical pancreatic cancer samples to identify the molecular subtypes of pancreatic cancer these cell lines represent...
2017: PloS One
Mei Zeng, Jia Lu, Lianbo Li, Frederic Feru, Chunshan Quan, Thomas W Gero, Scott B Ficarro, Yuan Xiong, Chiara Ambrogio, Raymond M Paranal, Marco Catalano, Jay Shao, Kwok-Kin Wong, Jarrod A Marto, Eric S Fischer, Pasi A Jänne, David A Scott, Kenneth D Westover, Nathanael S Gray
Targeted covalent small molecules have shown promise for cancers driven by KRAS G12C. Allosteric compounds that access an inducible pocket formed by movement of a dynamic structural element in KRAS, switch II, have been reported, but these compounds require further optimization to enable their advancement into clinical development. We demonstrate that covalent quinazoline-based switch II pocket (SIIP) compounds effectively suppress GTP loading of KRAS G12C, MAPK phosphorylation, and the growth of cancer cells harboring G12C...
August 17, 2017: Cell Chemical Biology
Jia Lu, Rane A Harrison, Lianbo Li, Mei Zeng, Sudershan Gondi, David Scott, Nathanael S Gray, John R Engen, Kenneth D Westover
KRAS G12C, the most common RAS mutation found in non-small-cell lung cancer, has been the subject of multiple recent covalent small-molecule inhibitor campaigns including efforts directed at the guanine nucleotide pocket and separate work focused on an inducible pocket adjacent to the switch motifs. Multiple conformations of switch II have been observed, suggesting that switch II pocket (SIIP) binders may be capable of engaging a range of KRAS conformations. Here we report the use of hydrogen/deuterium-exchange mass spectrometry (HDX MS) to discriminate between conformations of switch II induced by two chemical classes of SIIP binders...
September 5, 2017: Structure
Alexios Matikas, Alexandra Voutsina, Eleni Lagoudaki, Dora Hatzidaki, Maria Trypaki, Giannis Stoupis, Maria Tzardi, Dimitrios Mavroudis, Vasilios Georgoulias
INTRODUCTION: The presence of KRAS mutations in patients with metastatic colorectal cancer (mCRC) predicts poor response to agents targeting the EGFR. Even in patients with RAS wild type (WT) tumors, resistance eventually develops due to multiple mechanisms, including the expansion of previously undetected KRAS mutated clones. In this feasibility study, we aimed to detect KRAS exon 2 mutations in serial samples of circulating tumor cells (CTCs) of RAS WT patients with mCRC captured by the Isolation by Size of Epithelial Tumor cells (ISET) system...
August 2017: Translational Oncology
N Giamblanco, S Petralia, S Conoci, C Messineo, G Marletta
The discrimination of a fully matched, unlabeled KRAS wild-type (WT) (C-G) target sample with respect to three of the most frequent KRAS codon mutations (G12 S (C-A), G12 R (C-C), G12C (C-T)) was investigated using an optimized detection strategy involving surface plasmon resonance (SPR), based on optimized probe-surface density and ionic strength control. The changes observed in the SPR signal were always larger for WT compared with the single-mismatch target DNA oligonucleotides, and were aligned with the theoretical energy differences between the base pair C-G, C-T, C-A, C-C...
October 1, 2017: Colloids and Surfaces. B, Biointerfaces
Paola Bordi, Marcello Tiseo, Eleonora Rofi, Iacopo Petrini, Giuliana Restante, Romano Danesi, Marzia Del Re
BACKGROUND: In patients with anaplastic lymphoma kinase (ALK)-positive non-small-cell lung cancer (NSCLC), disease progression occurs after a median of 9 to 10 months of crizotinib treatment. Several mechanisms of resistance have been identified and include ALK mutations and amplification or the activation of bypassing signaling pathways. Rebiopsy in NSCLC patients represents a critical issue and the analysis of circulating cell-free DNA (cfDNA) has a promising role for the identification of resistance mechanisms...
November 2017: Clinical Lung Cancer
Hestia Mellert, Trudi Foreman, Leisa Jackson, Dianna Maar, Scott Thurston, Kristina Koch, Amanda Weaver, Samantha Cooper, Nicholas Dupuis, Ubaradka G Sathyanarayana, Jakkie Greer, Westen Hahn, Dawne Shelton, Paula Stonemetz, Gary A Pestano
Nearly 80% of cancer patients do not have genetic mutation results available at initial oncology consultation; up to 25% of patients begin treatment before receiving their results. These factors hinder the ability to pursue optimal treatment strategies. This study validates a blood-based genome-testing service that provides accurate results within 72 hours. We focused on targetable variants in advanced non-small cell lung carcinoma-epidermal growth factor receptor gene (EGFR) variant L858R, exon 19 deletion (ΔE746-A750), and T790M; GTPase Kirsten ras gene (KRAS) variants G12C/D/V; and echinoderm microtubule associated protein like and 4 anaplastic lymphoma receptor tyrosine kinase fusion (EML4-ALK) transcripts 1/2/3...
May 2017: Journal of Molecular Diagnostics: JMD
Sehhoon Park, Ji-Yeon Kim, Se-Hoon Lee, Beomseok Suh, Bhumsuk Keam, Tae Min Kim, Dong-Wan Kim, Dae Seog Heo
BACKGROUND/AIMS: The predictive and prognostic value of KRAS mutation and its type of mutations in non-small cell lung cancer (NSCLC) are controversial. This clinical study was designed to investigate the predictive value of KRAS mutations and its mutation types to pemetrexed and gemcitabine based treatment. METHODS: Advanced NSCLC patients tested for KRAS mutation (n = 334) were retrospectively reviewed and 252 patients with wild type epidermal growth factor receptor and no anaplastic lymphoma kinase fusion were enrolled for the analysis...
May 2017: Korean Journal of Internal Medicine
Robert P Jones, Paul A Sutton, Jonathan P Evans, Rachel Clifford, Andrew McAvoy, James Lewis, Abigail Rousseau, Roger Mountford, Derek McWhirter, Hassan Z Malik
BACKGROUND: Activating mutations in KRAS have been suggested as potential predictive and prognostic biomarkers. However, the prognostic impact of specific point mutations remains less clear. This study assessed the prognostic impact of specific KRAS mutations on survival for patients with colorectal cancer. METHODS: Retrospective review of patients KRAS typed for advanced and recurrent colorectal cancer between 2010 and 2015 in a UK Cancer Network. RESULTS: We evaluated the impact of KRAS genotype in 392 patients...
March 28, 2017: British Journal of Cancer
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