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Background Rat sarcoma viral oncogene homolog (RAS) gene mutation is a common molecular event in colorectal cancer (CRC). The prognosis of mCRC (metastatic colorectal cancer) patients with RAS mutation is poor and capecitabine and oxaliplatin (CapeOx) plus bevacizumab has shown to be one of the standard therapeutic regimens as first line for these patients with objective response rate (ORR) of ~ 50% and median progression-free survival (mPFS) of 8–9 months. Immunotherapy, especially anti-programmed death 1 (PD-1) monoclonal antibody has demonstrated ground-breaking results in deficient mismatch repair (dMMR) / microsatellite instability-high (MSI-H) mCRC patients. However, the response rate of in microsatellite stable (MSS) patients is extremely low. In addition, preclinical studies have demonstrated that anti - Vascular endothelial growth factor (VEGF) agents, such as bevacizumab, can induce tumor vascular normalization and enhance antitumor immunity. Previous study indicated the combination of chemotherapy, anti-VEGF agents (bevacizumab) with immune checkpoint inhibitors may have promising clinical activity in RAS mutant, MSS refractory mCRC patients. Based on these evidences, we will explore the combination of CapeOx with bevacizumab and sintilimab (anti-PD-1 monoclonal antibody) in RAS mutant, MSS mCRC patients as first-line therapy. Methods This is a randomized, open-label, multicentric clinical trial. In the sintilimab arm, patients will receive sintilimab in combination with CapeOx and bevacizumab. In the control arm, patients will receive CapeOx and bevacizumab. This trial will recruit 494 patients from 20 centers and randomly (1:1) disseminated into two groups. The primary endpoint is the PFS. The secondary endpoints include overall survival, safety, ORR, and disease control rate. Discussion This study may provide new ideas for optimizing oncology treatment planning for RAS mutant, MSS mCRC patients in the first-line set. Trial registration This study is short for BBCAPX and has been registered at clinicaltrials.gov registry with identifier NCT05171660.

Background: Aberrant activation of RAS-RAF-MEK-ERK signaling pathway has been implicated in more than one-third of all malignancies. MEK inhibitors are promising therapeutic approaches to target this signaling pathway. Though four MEK inhibitors have been approved by FDA, these compounds possess either limited efficacy or unfavorable PK profiles with toxicity issues, hindering their broadly application in clinic. Our efforts were focused on the design and development of a novel MEK inhibitor, which subsequently led to the discovery of tunlametinib. Methods: This study verified the superiority of tunlametinib over the current MEK inhibitors in preclinical studies. The protein kinase selectivity activity of tunlametinib was evaluated against 77 kinases. Anti-proliferation activity was analyzed using the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) or (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay. ERK and phospho-ERK levels were evaluated by Western blot analysis. Flow cytometry analysis was employed to investigate cell cycle and arrest. Cell-derived xenograft (CDX) and Patient-derived xenograft (PDX) models were used to evaluate the tumor growth inhibition. The efficacy of tunlametinib as monotherapy treatment was evaluated in KRAS/BRAF mutant or wild type xenograft model. Furthermore, the combination studies of tunlametinib with BRAF/KRAS G12C /SHP2 inhibitors or chemotherapeutic agent were conducted by using the cell proliferation assay in vitro and xenograft models in vivo . Results: In vitro , tunlametinib demonstrated high selectivity with approximately 19-fold greater potency against MEK kinase than MEK162, and nearly 10–100-fold greater potency against RAS/RAF mutant cell lines than AZD6244. In vivo, tunlametinib resulted in dramatic tumor suppression and profound inhibition of ERK phosphorylation in tumor tissue. Mechanistic study revealed that tunlametinib induced cell cycle arrest at G0/G1 phase and apoptosis of cells in a dose-proportional manner. In addition, tunlametinib demonstrated a favorable pharmacokinetic profile with dose-proportionality and good oral bioavailability, with minimal drug exposure accumulation. Furthermore, tunlametinib combined with BRAF/KRAS G12C /SHP2 inhibitors or docetaxel showed synergistically enhanced response and marked tumor inhibition. Conclusion: Tunlametinib exhibited a promising approach for treating RAS/RAF mutant cancers alone or as combination therapies, supporting the evaluation in clinical trials. Currently, the first-in-human phase 1 study and pivotal clinical trial of tunlametinib as monotherapy have been completed and pivotal trials as combination therapy are ongoing.

RAS is the most frequently mutated oncoprotein for cancer driving. Understanding of RAS biology and discovery of druggable lynchpins in RAS pathway is a prerequisite for targeted therapy of RAS-mutant cancers. The recent identification of KRAS G12C inhibitor breaks the “undruggable” curse on RAS and has changed the therapy paradigm of KRAS-mutant cancers. However, KRAS mutations, let alone KRAS G12C mutation, account for only part of RAS-mutated cancers. Targeted therapies for cancers harboring other RAS mutations remain the urgent need. In this study we explored the pivotal regulatory molecules that allow for broad inhibition of RAS mutants. By comparing the expression levels of nucleotide pyrophosphatase (NPPS) in a panel of cell lines and the functional consequence of increased NPPS expression in RAS-mutant cells, we demonstrated that cancer cells with various kinds of RAS mutations depended on NPPS for growth and survival, and that this dependence conferred a vulnerability of RAS-mutant cancer to treatment of NPPS inhibition. RAS-mutant cells, compared with RAS-wildtype cells, bored and required an upregulation of NPPS. Transcriptomics and metabolomics analyses revealed a NPPS-dependent hyperglycolysis in RAS-mutant cells. We demonstrated that NPPS promoted glucose-derived glycolytic intermediates in RAS-mutant cells by enhancing its interaction with hexokinase 1 (HK1), the enzyme catalyzing the first committed step of glycolysis. Pharmacological inhibition of NPPS-HK1 axis using NPPS inhibitor Enpp-1-IN-1 or HK1 inhibitor 2-deoxyglucose (2-DG), or genetic interfere with NPPS suppressed RAS-mutant cancers in vitro and in vivo. In conclusion, this study reveals an unrecognized mechanism and druggable lynchpin for modulation of pan-mutant-RAS pathway, proposing a new potential therapeutic approach for treating RAS-mutant cancers.

Background Targeting RAS mutant (MT) colorectal cancer (CRC) remains a difficult challenge, mainly due to the pervasiveness of RAS/MEK-mediated feedback loops. Preclinical studies identified MET/STAT3 as an important mediator of resistance to KRAS-MEK1/2 blockade in RAS MT CRC. This dose escalation/expansion study assessed safety and initial efficacy of the MEK1/2 inhibitor binimetinib with MET inhibitor crizotinib in RAS MT advanced CRC patients. Methods In the dose escalation phase, patients with advanced solid tumours received binimetinib with crizotinib, using a rolling- 6 design to determine the maximum tolerable dose (MTD) and safety/tolerability. A subsequent dose expansion in RAS MT CRC patients assessed treatment response. Blood samples for pharmacokinetics, MET biomarker and ctDNA analyses, and skin/tumour biopsies for pharmacodynamics, c-MET immunohistochemistry (IHC), MET in situ hybridisation (ISH) and MET DNA-ISH analyses were collected. Results Twenty patients were recruited in 3 cohorts in the dose escalation. The MTD was binimetinib 30 mg B.D, days 1–21 every 28 days, with crizotinib 250 mg O.D continuously. Dose-limiting toxicities included grade ≥ 3 transaminitis, creatinine phosphokinase increases and fatigue. Thirty-six RAS MT metastatic CRC patients were enrolled in the dose expansion. Pharmacokinetic and pharmacodynamic parameters showed evidence of target engagement. Across the entire study, the most frequent treatment-related adverse events (TR-AE) were rash (80.4%), fatigue (53.4%) and diarrhoea (51.8%) with grade ≥ 3 TR-AE occurring in 44.6%. Best clinical response within the RAS MT CRC cohort was stable disease in seven patients (24%). Tumour MET super-expression (IHC H-score > 180 and MET ISH + 3) was observed in 7 patients (24.1%), with MET -amplification only present in 1 of these patients. This patient discontinued treatment early during cycle 1 due to toxicity. Patients with high baseline  RAS MT allele frequency had a significant shorter median overall survival compared with that seen for patients with low baseline  KRAS MT allele frequency. Conclusions Combination binimetinib/crizotinib showed a poor tolerability with no objective responses observed in RAS MT advanced CRC patients. EudraCT-Number: 2014–000463 - 40 (20/06/2014: A Sequential Phase I study of MEK1/2 inhibitors PD- 0325901 or Binimetinib combined with cMET inhibitor Crizotinib in RAS Mutant and RAS Wild Type with aberrant c-MET).

ABSTRACT Phosphatidylinositol-3-kinase (PI3K) mediated or Ras/PI3K/PTEN/Akt/mTOR is one of the major effec-tor pathways in the pathogenesis of Non-Hodgkin Lymphoma (NHL). Binding of growth factors/mito-gen/cytokine or interleukin to EGFR leads to Ras induced RAF-MAPK cascade activation. PTEN protein is involved in the negative regulation of PI3K pathway. Mutations in upstream kinases, growth factor receptors or intrinsic members of cascades can lead to induce or promote cancers. Number of somatic mutations in several genes, majority of which are involved in chromatin modification and transcriptional regulation, have been reported in NHL. G468R and G468A mutations in BRAF gene have been report-ed in NHL, BRAF is a member of RAS mediated MAPK pathway. In current study, hot spots of Kras gene were analysed in a 40 years old male patient, presented with NHL located in ascending colon with worst prognosis of disease. Through mutagenic PCR, codon 12 was analysed by creating a single nucleotide mismatch at the 3'-end of primers to produce a BstNI recognition sequence at codon 12 while codon 13 was analysed by introducing HaeIII recognition sequence. By using RFLP and sequencing, point mutation substituting the glycine (GGC) to aspartic acid (GAC) was observed at codon 13. The p.G13D or cDNA.230G>A/g.5590G>A is previously recognized as rs112445441 and being reported for the first time in NHL. By in silico analysis, it is anticipated to be a diseases causing or pathogenic alteration by Mutation taster and SIFT analysis. Spotting the rs112445441 in NHL is supporting the idea of cross talk between RAS-ERK-MAPK and PI13K and this could be one of the factors behind the development of resistance to the current therapy and relapse in NHL. K ras mutant isoforms, being the negative predictors for prognosis, are vital to analyse before the start of adjuvant therapy. Further studies needed to confirm the functional aspects of rs1124 45441 and other variants involved in NHL pathogenesis.

To clarify the role of the H-Ras in vivo, we generated H-ras null mutant mice by gene targeting. In spite of the importance of the Ras in cell proliferation and differentiation, H-ras null mutant mice grew normally and were fertile. The oldest H-ras mutant mice grew to be more than 30 months old. We used the H-ras deficient mice to study the importance of the H-ras and other ras genes in the development of skin tumors induced by initiation with 7, 12-dimethylbenz(a)anthracene (DMBA) followed by promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA). We showed that H-ras null mutant mice develop approximately six times less papillomas compared with wild-type littermates after 20 weeks of TPA treatment. While all papillomas examined (17 out of 17) in wild-type mice have mutations of H-ras at codon 61, 13 (62%) out of 21 papillomas in H-ras null mutant mice have mutations of K-ras gene at codon 12, 13, or 61 and another eight (38%) papillomas have no mutations in these codons of K-ras or N-ras genes. This suggests that the activation of H-ras gene is critical in the wild-type mice, but the activation of K-ras gene can replace the H-ras activation in the initiation step of skin tumor development in the H-ras deficient mice. Oncogene (2000).

C-H-ras proto-oncogene forms part of the signal transduction pathway of numerous external stimuli. This proto-oncogene is regulated by alternative splicing within its intron D due to the presence of the alternative intron D exon (IDX). The alternative splicing produces mRNA which encodes for the putative p19 protein, that lacks transforming potential. Herein, we demonstrated that SR proteins regulate the intron D splicing. Moreover, we studied the 2719 mutation of H-ras which has higher transforming potential than Ile12 and Val12 H-ras mutants and is also known to affect the 5' splice site of the IDX. However, here we show that the 2719 mutant can still be spliced when the upstream 5' splice-site is blocked. During these later studies, additionally, we generated a short 11 nucleotides 5' terminal exon that was fully defined and spliced in a bi-intronic pre-mRNA. The definition of this mini-exon was also addressed in this work.

There are 5 main histological types of thyroid cancers (TCs): papillary, follicular (also known as differentiated), poorly differentiated, anaplastic (the most aggressive form), and medullary TC, and only the latter arises from thyroid C cells. These different forms of TCs show significant variability, both among and within tumours. This great variation is particularly notable among the first 4 types, which all originate from thyroid follicular cells. Importantly, this heterogeneity is not limited to histopathological diversity only but is also manifested as variation in several genetic and/or epigenetic alterations, the numbers of interactions between the tumour and surrounding microenvironment, and interpatient differences, for example. All these factors contribute to the great complexity in the development of a tumour from cancer cells. In the present review, we summarise the knowledge accumulated about the heterogeneity of TCs. Further research in this direction should help to gain a better understanding of the underlying mechanisms contributing to the development and diversity of TCs, paving the way toward more effective treatment strategies.

To explore the immune microenvironment of RAS ‐mutated ( RAS mt) microsatellite stable (MSS) colon cancer (CC), we retrospectively performed whole exome sequencing, RNA sequencing, and robust digital pathology analyses and studied immune markers in a cohort of 161 patients treated with standard‐of‐care therapies with early stage disease (both fresh frozen and formalin‐fixed paraffin‐embedded [FFPE] samples) or 121 patients with metastatic setting (primary tumor FFPE samples). Only a small proportion of cases exhibited a highly infiltrated immune microenvironment, with a strong association between Immunoscore ® (IS)‐high (13% of the samples) and Tumor Lymphocytes Infiltrating Score (TuLIS)‐high scores (25% of the samples). Immunoscore Immune‐Checkpoint (ISIC)‐high tumors (52% of the samples) shared a similar microenvironment composition to IS‐high and TuLIS‐like high tumors and displayed higher mutational burdens than ISIC‐low tumors. In conclusion, a substantial proportion of MSS RAS mt CCs exhibit high ISIC scores, meriting evaluation in prospective trials of immunotherapy‐based combination regimens.

Mutated genes may lead to cancer development in numerous tissues. While more than 600 cancer-causing genes are known today, some of the most widespread mutations are connected to the RAS gene; RAS mutations are found in approximately 25% of all human tumors. Specifically, KRAS mutations are involved in the three most lethal cancers in the U.S., namely pancreatic ductal adenocarcinoma, colorectal adenocarcinoma, and lung adenocarcinoma. These cancers are among the most difficult to treat, and they are frequently excluded from chemotherapeutic attacks as hopeless cases. The mutated KRAS proteins have specific three-dimensional conformations, which perturb functional interaction with the GAP protein on the GAP–RAS complex surface, leading to a signaling cascade and uncontrolled cell growth. Here, we describe a gluing docking method for finding small molecules that bind to both the GAP and the mutated KRAS molecules. These small molecules glue together the GAP and the mutated KRAS molecules and may serve as new cancer drugs for the most lethal, most difficult-to-treat, carcinomas. As a proof of concept, we identify two new, drug-like small molecules with the new method; these compounds specifically inhibit the growth of the PANC-1 cell line with KRAS mutation G12D in vitro and in vivo. Importantly, the two new compounds show significantly lower IC50 and higher specificity against the G12D KRAS mutant human pancreatic cancer cell line PANC-1, as compared to the recently described selective G12D KRAS inhibitor MRTX-1133.