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1.
Chinese Journal of Cancer Biotherapy ; (6): 377-382, 2024.
Article Dans Chinois | WPRIM | ID: wpr-1016669

Résumé

@#[摘 要] 目的:探讨多结节非小细胞肺癌(NSCLC)组织中的驱动基因突变情况与临床病理特征的关系,为多结节NSCLC患者治疗提供分子诊断依据。方法:本研究共纳入2018年1月至2023年10月间云南省肿瘤医院分子诊断中心检测的121例多结节NSCLC患者的253个肺结节肿瘤组织标本,以第二代测序(NGS)技术或扩增阻滞突变系统PCR(ARMS-PCR)技术检测多结节NSCLC 组织中驱动基因突变情况,分析其与患者临床病理特征的关系,比较不同结节间肺癌驱动基因的突变异质性。结果:与非“宣威”NSCLC相比,“宣威”多结节NSCLC患者驱动基因突变具有显著的地域特点,表现在“宣威”患者具有较低(20%)的EGFR敏感突变(L858R、19-del)及较高(27.26%)的EGFR少见突变(主要为G719/S768I、G719);“宣威”多结节NSCLC患者的KRAS突变率(27.27%)亦显著高于非“宣威”患者突变率(12.59%)(P<0.05)。此外,“宣威”多结节NSCLC患者驱动基因突变不一致率高达69.23%,远高于非“宣威”患者驱动基因突变不一致率(55.07%)(P<0.05)。结论:“宣威”多结节NSCLC患者具有较高的EGFR少见突变及KRAS突变率,同一患者不同病灶之间存在更高的驱动基因突变异质性,本研究将为“宣威”多结节NSCLC的诊疗策略提供更多的选择。

2.
Article Dans Anglais | LILACS-Express | LILACS | ID: biblio-1535889

Résumé

Introduction: Several factors have been described to make a prognostic assessment of patients with liver metastases due to colorectal cancer and to define the benefit of the surgical management of metastatic involvement; one of these factors is the status of the KRAS gene since its mutation is associated with worse outcomes. This study aims to describe the outcomes for a retrospective series of patients after liver resections for metastatic colorectal cancer concerning KRAS gene status. Materials and methods: The study involves a retrospective cohort of patients undergoing liver metastasectomy for colorectal cancer with KRAS mutation study from 2009-2013 at the National Institute of Cancerology in Colombia. Five-year survival analyses (overall and disease-free) were performed according to KRAS mutation status and the type of liver resection performed using the Kaplan-Meier estimate. Results: 35 patients undergoing liver metastasectomy were analyzed, of which 42.8% had KRAS gene mutation. Median overall survival was 34.2 months for patients with KRAS- mutant and 46.5 for non-mutant. The median survival for KRAS-mutant patients with anatomic resections was 43.5 months versus 23.5 months for nonanatomic resections. Conclusions: Performing anatomic resections during liver metastasectomy in patients with KRAS mutants could be associated with an improvement in overall survival. It is necessary to continue building the evidence for adequate decision-making in patients with KRAS mutants who will undergo liver resections.


Introducción: se han descrito varios factores para realizar una evaluación pronóstica de los pacientes con metástasis hepáticas por cáncer colorrectal y definir el beneficio en el manejo quirúrgico del compromiso metastásico; uno de estos factores es el estado del gen KRAS, debido a que su mutación está relacionada con peores desenlaces. El objetivo de este estudio es describir los desenlaces para una serie retrospectiva de pacientes después de resecciones hepáticas por metástasis de cáncer colorrectal en relación con el estado del gen KRAS. Metodología: cohorte retrospectiva de pacientes llevados a metastasectomía hepática por cáncer colorrectal con estudio de mutación KRAS durante el período 2009-2013, en el Instituto Nacional de Cancerología en Colombia. Se realizaron análisis de supervivencia a 5 años (global y libre de enfermedad) según el estado de mutación KRAS y según el tipo de resección hepática realizada mediante el método de Kaplan-Meier. Resultados: se analizaron a 35 pacientes llevados a metastasectomía hepática, de los cuales el 42,8% presentaba mutación del gen KRAS. La supervivencia global media fue de 34,2 meses para los pacientes con KRAS mutado y de 46,5 para los no mutados. La supervivencia media para los pacientes con KRAS mutado con resecciones anatómicas fue de 43,5 meses frente a 23,5 meses en los que se realizaron resecciones no anatómicas. Conclusiones: realizar resecciones anatómicas durante la metastasectomía hepática en los pacientes con KRAS mutado podría estar asociado con una mejoría en la supervivencia global. Se requiere continuar en la construcción de la evidencia que permita una adecuada toma de decisiones de los pacientes con KRAS mutado que serán llevados a resecciones hepáticas.

3.
Cancer Research and Clinic ; (6): 361-365, 2023.
Article Dans Chinois | WPRIM | ID: wpr-996239

Résumé

Objective:To explore KRAS, NRAS, BRAF gene mutations and microsatellite instability(MSI) in colorectal cancer tissues as well as their correlation with the clinicopathological characteristics of patients.Methods:The clinicopathological data of 473 colorectal cancer patients in Shanxi Province Cancer Hospital from October 2020 to May 2021 were retrospectively analyzed. The mutation status of KRAS, NRAS and BRAF gene in the paraffin tissues were detected by using amplification refractory mutation system (ARMS) method. Polymerase chain reaction (PCR)-capillary electrophoresis was used to analyze MSI status, and the correlation of the clinicopathological characteristics of patients with gene mutations and MSI status was analyzed.Results:The mutation rates of KRAS, NRAS and BRAF were 45.03% (213/473), 2.96% (14/473) and 5.50% (26/473), respectively in 473 patients with colorectal cancer. No case harbored both 2 gene mutations was detected. The mutation rate of KRAS gene in well differentiated adenocarcinoma was higher than that in poorly differentiated adenocarcinoma [47.4% (175/369) vs. 36.5% (38/104), χ2 = 3.89, P = 0.049]. NRAS mutation rate in female was higher than that in male [5.0% (10/202) vs. 1.5% (4/271), χ2 = 4.86, P = 0.027], and the NRAS mutation rate in patients with tumor diameter ≤ 3 cm was higher than that in those with tumor diameter >3 cm [7.1% (7/98) vs. 1.9% (7/375), P = 0.013]. BRAF mutation rate of tumors located in colon was higher than that in rectum [11.7% (20/171) vs.2.0% (6/302), χ2 = 19.81, P < 0.001]; BRAF mutation rate in poorly differentiated tumor was higher than that in well differentiated tumor [10.6% (11/104) vs. 4.1% (15/369), χ2 = 6.62, P = 0.010]; BRAF mutation rate in patients with mucus was higher than that in those without mucus [10.9% (11/101) vs. 4.0% (15/372), χ2 = 7.19, P = 0.007]; BRAF mutation rate in patients with lymphatic metastasis was higher than that in patients without lymphatic metastasis [8.2% (15/182) vs.3.8% (11/291), χ2 = 4.29, P = 0.038]. The incidence of high frequency MSI (MSI-H) in 473 colorectal cancer tissues was 7.19% (34/473). The incidence of MSI-H in colon was higher than that in rectum [14.0% (24/171) vs. 3.3% (10/302), χ2 = 18.82, P < 0.001]; the incidence of MSI-H in patient with poor differentiated tumor was higher than that in those with well differentiated tumor [17.3% (18/104) vs. 4.3% (16/369), χ2 = 20.46, P < 0.001]; the incidence of MSI-H in patients with mucus was higher than that in those without mucus [11.9% (12/101) vs. 5.9% (22/372), χ2 = 4.24, P = 0.039]; and the incidence of MSI-H in patients without lymphatic metastasis was higher than that in patients with lymphatic metastasis [10.0% (29/291) vs. 2.7% (5/182), χ2 = 8.75, P = 0.003]. In addition, the incidence of MSI-H was on the rise in patients with BRAF mutation ( P < 0.001). Conclusions:KRAS, NRAS, BRAF gene mutations and MSI status are correlated with the clinicopathological characteristics of patients with colorectal cancer; there is a close relationship between MSI-H and BRAF mutation.

4.
Journal of Chinese Physician ; (12): 875-879,885, 2023.
Article Dans Chinois | WPRIM | ID: wpr-992393

Résumé

Objective:To analyze the mutation characteristics of Kirsten rat sarcoma virus oncogene homology (KRAS) gene in patients with appendiceal adenocarcinoma and its relationship with the activity of Ras Raf Mitogen activated protein kinase/extracellular regulated protein kinase (MAPK/ERK) signaling pathway.Methods:A total of 41 patients with appendiceal adenocarcinoma who were treated in the Lishui Central Hospital from January 2014 to January 2020 were selected as the observation group, and 50 patients with Appendicitis who were operated at the same time were randomly selected as the control group. Clinical and follow-up data were collected, and the mutation of the KRAS gene in the patient′s tissue was measured using the snapshot method. The expression of key proteins in the MAPK/ERK signaling pathway in cancer tissue was measured using Western blotting (WB) assay. We compared the clinical characteristics and prognosis of patients with KRAS mutation and non KRAS mutation appendiceal adenocarcinoma.Results:The KRAS gene mutation rate in the observation group was higher than that in the control group (41.5% vs 10.0%), and the expression levels of p-ARAF/ARAF, p-MEK1/MEK1, and p-ERK1/ERK1 proteins were also higher than those in the control group. The differences between the groups were statistically significant (all P<0.05). The protein expression levels of p-ARAF/ARAF, p-MEK1/MEK1, p-ERK1/ERK1 in KRAS mutation patients in the observation group were significantly higher than those in non KRAS mutation patients. The proportion of stage IV, positive rates of carcinoembryonic antigen (CEA), carbohydrate antigen (CA)199 and CA125 in KRAS mutation patients were higher than those in non KRAS mutation patients, and the survival time and progression free survival time were shorter than those in non KRAS mutation patients, with statistical significance (all P<0.05). Conclusions:The mutation rate of KRAS in appendix adenocarcinoma is high, and the activation of MAPK/ERK signaling pathway caused by KRAS mutation may play a role in the pathogenesis of appendix adenocarcinoma, which has the value of in-depth research.

5.
Acta Pharmaceutica Sinica B ; (6): 1145-1163, 2023.
Article Dans Anglais | WPRIM | ID: wpr-971757

Résumé

MEK is a canonical effector of mutant KRAS; however, MEK inhibitors fail to yield satisfactory clinical outcomes in KRAS-mutant cancers. Here, we identified mitochondrial oxidative phosphorylation (OXPHOS) induction as a profound metabolic alteration to confer KRAS-mutant non-small cell lung cancer (NSCLC) resistance to the clinical MEK inhibitor trametinib. Metabolic flux analysis demonstrated that pyruvate metabolism and fatty acid oxidation were markedly enhanced and coordinately powered the OXPHOS system in resistant cells after trametinib treatment, satisfying their energy demand and protecting them from apoptosis. As molecular events in this process, the pyruvate dehydrogenase complex (PDHc) and carnitine palmitoyl transferase IA (CPTIA), two rate-limiting enzymes that control the metabolic flux of pyruvate and palmitic acid to mitochondrial respiration were activated through phosphorylation and transcriptional regulation. Importantly, the co-administration of trametinib and IACS-010759, a clinical mitochondrial complex I inhibitor that blocks OXPHOS, significantly impeded tumor growth and prolonged mouse survival. Overall, our findings reveal that MEK inhibitor therapy creates a metabolic vulnerability in the mitochondria and further develop an effective combinatorial strategy to circumvent MEK inhibitors resistance in KRAS-driven NSCLC.

6.
Journal of Zhejiang University. Science. B ; (12): 143-156, 2023.
Article Dans Anglais | WPRIM | ID: wpr-971476

Résumé

This study aimed to identify subtypes of genomic variants associated with the efficacy of immune checkpoint inhibitors (ICIs) by conducting systematic literature search in electronic databases up to May 31, 2021. The main outcomes including overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and durable clinical benefit (DCB) were correlated with tumor genomic features. A total of 1546 lung cancer patients with available genomic variation data were included from 14 studies. The Kirsten rat sarcoma viral oncogene homolog G12C (KRASG12C) mutation combined with tumor protein P53 (TP53) mutation revealed the promising efficacy of ICI therapy in these patients. Furthermore, patients with epidermal growth factor receptor (EGFR) classical activating mutations (including EGFRL858R and EGFRΔ19) exhibited worse outcomes to ICIs in OS (adjusted hazard ratio (HR), 1.40; 95% confidence interval (CI), 1.01‍‒‍1.95; P=0.0411) and PFS (adjusted HR, 1.98; 95% CI, 1.49‍‒‍2.63; P<0.0001), while classical activating mutations with EGFRT790M showed no difference compared to classical activating mutations without EGFRT790M in OS (adjusted HR, 0.96; 95% CI, 0.48‍‒‍1.94; P=0.9157) or PFS (adjusted HR, 0.72; 95% CI, 0.39‍‒‍1.35; P=0.3050). Of note, for patients harboring the Usher syndrome type-2A(USH2A) missense mutation, correspondingly better outcomes were observed in OS (adjusted HR, 0.52; 95% CI, 0.32‍‒‍0.82; P=0.0077), PFS (adjusted HR, 0.51; 95% CI, 0.38‍‒‍0.69; P<0.0001), DCB (adjusted odds ratio (OR), 4.74; 95% CI, 2.75‍‒‍8.17; P<0.0001), and ORR (adjusted OR, 3.45; 95% CI, 1.88‍‒‍6.33; P<0.0001). Our findings indicated that, USH2A missense mutations and the KRASG12Cmutation combined with TP53 mutation were associated with better efficacy and survival outcomes, but EGFR classical mutations irrespective of combination with EGFRT790M showed the opposite role in the ICI therapy among lung cancer patients. Our findings might guide the selection of precise targets for effective immunotherapy in the clinic.


Sujets)
Humains , Carcinome pulmonaire non à petites cellules/génétique , Récepteurs ErbB/génétique , Protéines de la matrice extracellulaire/génétique , Inhibiteurs de points de contrôle immunitaires/usage thérapeutique , Tumeurs du poumon/génétique , Mutation , Inhibiteurs de protéines kinases/usage thérapeutique , Protéines proto-oncogènes p21(ras)/génétique , Résultat thérapeutique
7.
Chinese Journal of Clinical Pharmacology and Therapeutics ; (12): 130-137, 2023.
Article Dans Chinois | WPRIM | ID: wpr-1014677

Résumé

AIM: To investigate the mechanism and reversal effect of Zuo Jin Wan (ZJW) on cetuximab (CET) resistance in KRAS mutant colorectal cancer cell. METHODS: The mutation status of KRAS gene in SW620, Lovo, HCT116, HT29 and Caco2 cells were detected by Sanger sequencing. CCK-8 assay was used to detect the effects of ZJW, CET, ZJW combined with CET and CET, ZJW in combination with other cell death inhibitors on the survival rate of the above cells, and to observe the reversal effects of ZJW on CET-treated KRAS mutant cells (SW620, Lovo and HCT116). Flow cytometry, colorimetric method, and Fe

8.
Indian J Cancer ; 2022 Jun; 59(2): 236-243
Article | IMSEAR | ID: sea-221678

Résumé

Background: Mutations in the RAS genes, HRAS, KRAS, and NRAS, are the most common modifications in many types of human tumors and are found in approximately 30% of all human cancers. These mutations are usually found in codons 12, 13, or 61. Methods: The aim of this study is to evaluate mutations in codons 59, 117, and 146 of KRAS and NRAS genes in addition to codons 12,13, and 61 of KRAS gene in lung cancer tissue specimens obtained with bronchoscopy. KRAS and NRAS mutation analyses with pyrosequencing were performed on DNA isolated from formalin?fixed paraffin?embedded (FFPE) tissue samples of 64 patients histopathologically diagnosed as lung cancer after bronchoscopic biopsy. Results: In all, 20 patients (31.2%) had mutations in KRAS gene (8/27 squamous cell carcinoma, 8/11 adenocarcinoma, 3/16 small cell carcinoma, and 1/1 pleomorphic carcinoma). The most common mutation in codon 12 was in c.35G>T (G12V). When the mutation rate of adenocarcinoma (72.7%) and squamous cell carcinoma (22.9%) patients was compared with each other, a statistically significant difference was observed (P = 0.008). There were no mutations in codons 59, 117, or 146 of KRAS and NRAS genes in patients with lung cancer. Conclusion: In this study, we firstly examined mutations in codons 59, 117, and 146 of KRAS and NRAS genes in addition to codons 12, 13, and 61 of KRAS gene in Turkish lung cancer patients both in non?small cell lung cancer and small cell lung cancer. Although no mutation was detected in codons 59, 117, and 146 of KRAS and NRAS genes, the frequency of KRAS gene mutation was higher than the rate of mutation in both Asian and Western countries, and multicenter studies including more cases should be performed to further explore our results.

9.
Indian J Cancer ; 2022 Jun; 59(2): 218-222
Article | IMSEAR | ID: sea-221675

Résumé

Background: The requirement for the mutation analysis for Kirsten rat sarcoma viral oncogene (KRAS) in colorectal cancer (CRC) is rapidly increasing as it is a predictive biomarker and also, its absence signifies response to anti?epidermal growth factor receptor (anti?EGFR) antibody treatment. The aim of our study was to investigate the pathological diagnosis and distribution of KRAS mutations in colorectal cancer with the use of next generation sequencing platform (Ion Torrent). Methods: A total of 56 CRC samples were tested to identify the genetic mutations, especially KRAS using the primers which included ~2800 COSMIC mutations of 50 oncogenes. Ion Torrent personal genome machine (semiconductor?based sequencing) was used for the sequencing and analysis. Along with KRAS, other 49 genes were also studied for COSMIC mutations. Results: KRAS mutation 25 (44.6%) had the highest frequency, followed by TP53 10 (17.9%) and PIK3CA mutation 4 (7.1%). Of all the KRAS mutations identified, mutations in codon 12 were most frequent followed by mutations in codon 13 and 61. The most frequent substitution was glycine to aspartate mutation in codon 12 (p.Gly12Asp) followed by glycine to valine (p.Gly12Val). Combinations of mutations were also studied. Our study revealed that seven cases (12.5%) had both KRAS and TP53 mutations (highest of all the combinations). Conclusion: The analysis of KRAS mutation frequency and its mutational subtype analysis in human CRCs by using semiconductor?based platform in routine clinical practices have been performed in Indian population. The findings were similar to earlier published reports from the Western literature.

10.
Article | IMSEAR | ID: sea-223622

Résumé

Background & objectives: Inflammation has been studied to be an important contributory factor to carcinogenesis through pro-inflammatory markers such as interleukin (IL)-6 and C-reactive protein (CRP). Furthermore, K-ras mutation is an important genetic alteration in the pathogenesis of pancreatic cancer. This study aimed to compare these inflammatory markers in pancreatic ductal adenocarcinoma (PDAC) with the diseased and healthy controls (HCs) and to check for any association between IL-6 and CRP serum levels with the disease status, survival and K-ras mutation status of PDAC patients. Methods: The study included 135 PDAC, 25 chronic pancreatitis (CP) patients and 25 HCs. The serum levels of IL-6 and CRP were detected by enzyme-linked immunosorbent assay and K-ras mutations were detected by polymerase chain reaction-restriction fragment length polymorphism technique. Results: The serum levels of both these markers were elevated in PDAC cases than that in HCs. High IL-6 levels and higher CRP levels were found to be associated with locally advanced disease, lymphatic invasion, metastasis and advanced stage of the PDAC. In patients with unresectable PDAC, higher IL-6 levels were found to be associated with the presence of K-ras mutations. Interpretation & conclusions: Higher IL-6 and CRP levels in patients with advanced PDAC suggest an important role of these inflammatory markers in tumour progression. Furthermore, the association of mutations in the K-ras gene with serum IL-6 indicates cross-talks that may contribute to the progression of the PDAC.

11.
Acta Pharmaceutica Sinica ; (12): 271-276, 2022.
Article Dans Chinois | WPRIM | ID: wpr-922923

Résumé

KRAS is one of the most frequently mutated human oncogenes. In spite of mounting efforts on the development of direct or indirect inhibition targeting KRAS, little has been achieved because of insurmountable difficulties, titling KRAS "undruggable". Recently, subtype-specific inhibitors have shown great hope. Some KRASG12C inhibitors have entered clinical trials, including adagrasib and sotorasib, and have shown preliminary clinical effectiveness. Experiences from the inhibitors targeting the downstream factors of RAS pathways show that the anticancer activity of these drugs will be limited due to the development of drug resistance. Preclinical studies of KRASG12C inhibitors have revealed that the application of these agents might be hampered by the drug resistance issue. The current review aims to describe the current status of KRASG12C inhibitors, and discuss the mechanisms underlying KRASG12C inhibitor resistance, so as to provide the clues for the combat of drug resistance.

12.
Acta Pharmaceutica Sinica B ; (6): 274-290, 2022.
Article Dans Anglais | WPRIM | ID: wpr-929293

Résumé

KRAS‒PDEδ interaction is revealed as a promising target for suppressing the function of mutant KRAS. The bottleneck in clinical development of PDEδ inhibitors is the poor antitumor activity of known chemotypes. Here, we identified novel spiro-cyclic PDEδ inhibitors with potent antitumor activity both in vitro and in vivo. In particular, compound 36l (K D = 127 ± 16 nmol/L) effectively bound to PDEδ and interfered with KRAS-PDEδ interaction. It influenced the distribution of KRAS in Mia PaCa-2 cells, downregulated the phosphorylation of t-ERK and t-AKT and promoted apoptosis of the cells. The novel inhibitor 36l exhibited significant in vivo antitumor potency in pancreatic cancer patient-derived xenograft (PDX) models. It represents a promising lead compound for investigating the druggability of KRAS‒PDEδ interaction.

13.
Chinese Journal of Lung Cancer ; (12): 477-481, 2022.
Article Dans Chinois | WPRIM | ID: wpr-939734

Résumé

Proteolysis targeting chimeria (PROTAC) degrades target proteins by utilizing the ubiquitin-proteasome pathway, subverting the concept of traditional small molecule inhibitors. Among the common mutation targets of non-small cell lung cancer (NSCLC), PROTAC technology has successfully achieved the effective degradation of kirsten rat sarcoma viral oncogene homolog (KRAS), epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK ) and other proteins in preclinical studies. PROTAC drugs with their unique event-driven advantages, are expected to overcome acquired drug resistance caused by small molecule inhibitors and show good therapeutic potential for undruggable targets, thereby providing a new strategy for the treatment of NSCLC.
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Sujets)
Humains , Carcinome pulmonaire non à petites cellules/anatomopathologie , Tumeurs du poumon/anatomopathologie , Mutation , Inhibiteurs de protéines kinases/usage thérapeutique , Protéolyse , Protéines proto-oncogènes p21(ras)/génétique
14.
Med. j. Zambia ; 49(2): 128-137, 2022. tales, figures
Article Dans Anglais | AIM | ID: biblio-1402632

Résumé

ackground: The second leading cause of cancerrelated deaths worldwide iscolorectal cancer. With an incidence rate of 4.8 per 100,000, this is Zambia's sixth most prevalent cancer; Methods: This laboratory-based, cross-sectional study examined the frequency of Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation and its association with prognostic factors in colorectal carcinoma cases from the University Teaching Hospital-Adult Hospital (UTHs), Lusaka, Zambia; Results: Thirty (30) formalin-fixed paraffinembedded (FFPE) samples collected between June 2017 and June 2018 were sent to the Lancet laboratories and analyzed for KRAS mutations (codons 12 and 13). One FFPE block did not meet the inclusion criteria and was excluded. The demographic and clinicopathological data were analyzed using STATA 12. Males outnumber females by 20 to nine. The average age of the patient was 45 ± 16 years. The rectum was the location of 44.8% of the tumors, with the majority being conventional adenocarcinoma (CAC) (65.6 %). All cases (100%) had advanced-stage (stages 3 and 4) disease;however, only 27.6% of patient tumors exhibited lymphovascular invasion. KRAS mutation was detected in 11 (37.9%) cases and mainly in left-sided tumors (62.5%). KRAS mutations were only detected in CAC and serrated adenocarcinoma subtypes. No significant associations were observed between the KRAS mutation status and tumor or patient's clinical and sociodemographic factors; Conclusion: We advocate for incorporating KRAS mutation testing into the standard of care for treating colorectal cancer.


Sujets)
Humains , Oncogènes , Adénocarcinome , Tumeurs colorectales , Mutation
15.
Journal of Pharmaceutical Analysis ; (6): 232-242, 2022.
Article Dans Chinois | WPRIM | ID: wpr-931250

Résumé

Folate receptor(FR)overexpression occurs in a variety of cancers,including pancreatic cancer.In addi-tion,enhanced macropinocytosis exists in K-Ras mutant pancreatic cancer.Furthermore,the occurrence of intensive desmoplasia causes a hypoxic microenvironment in pancreatic cancer.In this study,a novel FR-directed,macropinocytosis-enhanced,and highly cytotoxic bioconjugate folate(F)-human serum albumin(HSA)-apoprotein of lidamycin(LDP)-active enediyne(AE)derived from lidamycin was designed and prepared.F-HSA-LDP-AE consisted of four moieties:F,HSA,LDP,and AE.F-HSA-LDP presented high binding efficiency with the FR and pancreatic cancer cells.Its uptake in wild-type cells was more extensive than in K-Ras mutant-type cells.By in vivo optical imaging,F-HSA-LDP displayed prominent tumor-specific biodistribution in pancreatic cancer xenograft-bearing mice,showing clear and lasting tumor localization for 360 h.In the MTT assay,F-HSA-LDP-AE demonstrated potent cytotoxicity in three types of pancreatic cancer cell lines.It also induced apoptosis and caused G2/M cell cycle arrest.F-HSA-LDP-AE markedly suppressed the tumor growth of AsPc-1 pancreatic cancer xenografts in athymic mice.At well-tolerated doses of 0.5 and 1 mg/kg,(i.v.,twice),the inhibition rates were 91.2%and 94.8%,respectively(P<0.01).The results of this study indicate that the F-HSA-LDP multi-functional bioconjugate might be effective for treating K-Ras mutant pancreatic cancer.

16.
An. Fac. Cienc. Méd. (Asunción) ; 54(3): 33-40, Dec. 2021.
Article Dans Espagnol | LILACS | ID: biblio-1352903

Résumé

El estado mutacional del KRAS ha sido considerado como biomarcador para tratamientos biológicos tras varios ensayos clínicos realizados en pacientes con cáncer colorrectal metastásico. Reportes recientes indican que las frecuencias de mutación del gen KRAS en pacientes con CCR de Asia, Europa y Latinoamérica están entre el 24%, 36% y 40%, respectivamente. Paraguay no cuenta con este tipo de informes, a pesar de registrar anualmente en promedio 75 nuevos casos de pacientes diagnosticados con CCR sólo en el Servicio de Cirugía General del Hospital Central del Instituto de Previsión Social (IPS). El presente trabajo ha implementado este análisis de rutina, prerrequisito obligatorio para la administración de fármacos basados en anticuerpos terapéuticos, y revelado una frecuencia de mutación del gen KRAS del 34% en pacientes paraguayos con CCR que acuden a los Servicios del Hospital Central del IPS


The mutational status of the KRAS has been consider as a biomarker for biological treatments after several clinical trials carried out in patient with metastatic colorectal cancer. Recent reports indicate that the KRAS gene mutation frequencies in CRC patients from Asia, Europe, and Latin America are between 24%, 36%, and 40%, respectively. Paraguay does not have this kind of reports, despite registering an average of 75 new cases of patients diagnosed with CRC per year only in the General Surgery Service of the "Central Hospital - Instituto de Prevision Social (IPS)". The present work has implemented this routine analysis, a mandatory prerequisite for the administration of drugs based on therapeutic antibodies and revealed a KRAS gene mutation frequency of 34% in Paraguayan patients with CRC who attend the IPS Central Hospital Services


Sujets)
Tumeurs colorectales , Mutation , Études transversales , Gènes
17.
Acta Pharmaceutica Sinica ; (12): 374-382, 2021.
Article Dans Chinois | WPRIM | ID: wpr-873780

Résumé

RAS, as a well-known proto-oncogene, is the most frequently mutated oncogene in human cancers, yet tremendous efforts over the past 30 years have failed to develop effective therapies for RAS-mutant cancer. Recently, specifically targeting the KRAS-G12C mutant, a frequently occurring KRAS mutation in human cancers, has shown promise in conquering KRAS-mutant cancers, and has inspired interest in this direction. We herein review the very recent progress achieved in the development of covalent inhibitors towards KRAS-G12C mutant, in combinational therapies and in proteolysis-targeting chimeras (PROTACs)-based approaches to disrupt KRAS-G12C protein. We provide insights for drug discovery against KRAS-G12C-mutated tumors and discuss the potential challenges in this field.

18.
Journal of Xi'an Jiaotong University(Medical Sciences) ; (6): 18-24, 2021.
Article Dans Chinois | WPRIM | ID: wpr-1006764

Résumé

【Objective】 To explore the different expressions of TP53, P16 and K-ras in gallbladder high-grade intraepithelial neoplasia and early carcinoma, and establish their mutation random forest prediction model. 【Methods】 We retrospectively analyzed the clinicopathological data of 71 patients who underwent cholecystectomy at The First Affiliated Hospital of Xi’an Jiaotong University from January 2013 to December 2018, including 20 cases of chronic cholecystitis, 28 cases of gallbladder high-grade intraepithelial neoplasia, and 23 cases of early gallbladder carcinoma. The immunohistochemical SP method was conducted to detect the expressions of TP53, P16 and K-ras in the gallbladder pathological tissues; the correlation between the above genes and clinicopathological data was analyzed. A random forest prediction model of each gene mutation was established based on the clinicopathological data and gene expression. 【Results】 The positive expressions of TP53, P16 and K-ras were related to the gallbladder with cholecystolithiasis or polyps and gallbladder pathological tissue type. The positive rates of the three genes in the gallbladder polyps were significantly higher than those in the cholecystolithiasis group (P<0.05). The positive rates of the three genes in the latter two groups of gallbladder high-grade intraepithelial neoplasia and early gallbladder carcinoma were significantly higher than those in the chronic cholecystitis (P<0.05), while there was no statistical difference between the latter two groups (P>0.05). The mutations of TP53, P16 and K-ras had a certain correlation (χ2=6.285, 19.595, 4.070, r=0.298, 0.525, 0.239, P<0.05). TP53, P16 and K-ras mutation prediction models based on random forest had good accuracy (AUC=77.42%, 80.06%, 71.75%, accuracy=76.06%, 76.06%, 67.61%). 【Conclusion】 TP53, P16 and K-ras gene mutations promote the transformation of chronic cholecystitis to gallbladder carcinoma. The mutation prediction model based on random forest has a good accuracy, which can provide an important reference for carcinogenesis and early diagnosis of gallbladder carcinoma.

19.
Biol. Res ; 54: 23-23, 2021. ilus, tab
Article Dans Anglais | LILACS | ID: biblio-1505793

Résumé

The Ras family of small Guanosine Triphosphate (GTP)-binding proteins (G proteins) represents one of the main components of intracellular signal transduction required for normal cardiac growth, but is also critically involved in the development of cardiac hypertrophy and heart failure. The present review provides an update on the role of the H-, K- and N-Ras genes and their related pathways in cardiac diseases. We focus on cardiac hypertrophy and heart failure, where Ras has been studied the most. We also review other cardiac diseases, like genetic disorders related to Ras. The scope of the review extends from fundamental concepts to therapeutic applications. Although the three Ras genes have a nearly identical primary structure, there are important functional differences between them: H-Ras mainly regulates cardiomyocyte size, whereas K-Ras regulates cardiomyocyte proliferation. N-Ras is the least studied in cardiac cells and is less associated to cardiac defects. Clinically, oncogenic H-Ras causes Costello syndrome and facio-cutaneous-skeletal syndromes with hypertrophic cardiomyopathy and arrhythmias. On the other hand, oncogenic K-Ras and alterations of other genes of the Ras-Mitogen-Activated Protein Kinase (MAPK) pathway, like Raf, cause Noonan syndrome and cardio-facio-cutaneous syndromes characterized by cardiac hypertrophy and septal defects. We further review the modulation by Ras of key signaling pathways in the cardiomyocyte, including: (i) the classical Ras-Raf-MAPK pathway, which leads to a more physiological form of cardiac hypertrophy; as well as other pathways associated with pathological cardiac hypertrophy, like (ii) The SAPK (stress activated protein kinase) pathways p38 and JNK; and (iii) The alternative pathway Raf-Calcineurin-Nuclear Factor of Activated T cells (NFAT). Genetic alterations of Ras isoforms or of genes in the Ras-MAPK pathway result in Ras-opathies, conditions frequently associated with cardiac hypertrophy or septal defects among other cardiac diseases. Several studies underline the potential role of H- and K-Ras as a hinge between physiological and pathological cardiac hypertrophy, and as potential therapeutic targets in cardiac hypertrophy and failure. Highlights - The Ras (Rat Sarcoma) gene family is a group of small G proteins - Ras is regulated by growth factors and neurohormones affecting cardiomyocyte growth and hypertrophy - Ras directly affects cardiomyocyte physiological and pathological hypertrophy - Genetic alterations of Ras and its pathways result in various cardiac phenotypes? - Ras and its pathway are differentially regulated in acquired heart disease - Ras modulation is a promising therapeutic target in various cardiac conditions.


Sujets)
Humains , Cardiopathies congénitales , Syndrome de Noonan , Transduction du signal , Cardiomégalie , Mitogen-Activated Protein Kinases/métabolisme , Système de signalisation des MAP kinases
20.
Acta Pharmaceutica Sinica ; (12): 1562-1570, 2021.
Article Dans Chinois | WPRIM | ID: wpr-881547

Résumé

The RAS (rat sarcoma) gene is one of the important oncogenes, and its mutation is present in about 30% human tumors. KRAS (kirsten rat sarcoma viral oncogene) is one of the three RAS subtypes, and KRAS mutations are more common than the mutations in other two RAS subtypes. In recent years, with the continuous research, new ideas have been provided for the treatment of cancers via targeting-KRAS. Efforts have been made to develop various KRAS inhibitors. Here, based on the mechanism of action, we classified KRAS inhibitors into two categories: inhibitors that directly target KRAS and inhibitors that indirectly act on KRAS. The representative KRAS inhibitors were summarized and introduced in this paper.

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