NRAS Q61

We elucidated the mechanism of action of a potent KRAS G12D inhibitor, MRTX1133. Binding of this inhibitor to the switch-2 pocket causes a complete shift of KRAS G12D towards the "inactive" conformation and prevents binding of effector RAS-binding domain (RBD) at physiological concentrations, by signaling through an allosteric network.

Since BRAF activation occurs in BRAF fusion gene tumors and BRAF mutations, they could share a similar mechanism in tumorigenesis. This case suggests the further expansion of kinase-related spindle cell tumors.

These findings suggest that UV-driven malignancies (including melanoma or sarcomatoid squamous cell carcinoma) may histologically mimic eMFS and should be considered in cases of eMFS presenting at atypical anatomical sites.

P1, N=120, Active, not recruiting, InxMed (Shanghai) Co., Ltd. | Recruiting --> Active, not recruiting | Trial completion date: Sep 2024 --> Dec 2025 | Trial primary completion date: Jun 2024 --> Jun 2025

Mechanistically, CK1δ directly phosphorylates USP46 and activates its deubiquitinase activity towards NRAS mutants, thus promoting oncogenic NRAS-driven melanocyte malignant transformation and melanoma progression in vitro and in vivo. Our findings underscore the significance of the CK1δ-USP46 axis in stabilizing oncogenic NRAS mutants and provide preclinical evidence that targeting this axis holds promise as a therapeutic strategy for human melanoma harboring NRAS mutations.

The results obtained in this study explain the diverse genetic mutations in various grades of oral squamous cell carcinoma. Identification of these mutations would help in providing better treatment, designing a proper treatment plan for the patients with OSCC and support minimal intervention medicine.

Two frontline BRAF inhibitors (BRAFi), vemurafenib and dabrafenib, are frequently used to treat unresectable or metastatic BRAF V600E melanoma. Our data support the feasibility of the development of CRISPR-Cas therapeutic approaches to the treatment of melanoma. Successful therapeutic CRISPR-directed gene editing would enable both specific and efficient editing of a mutation-specific targeting approach eliminate concern for on- and off-target damage to the genomes of healthy cells.

The finding of synchronous mutations is a rare occurrence suggesting for intratumoral heterogeneity (ITH) even in PTC. Patients with multiple mutations have a clinical worse prognosis, generally characterized by an aggressive thyroid cancer, which may influence the surgical treatment, chemotherapy, and BRAF V600E mutation-targeting therapy.

KRAS Q61 and NRAS Q61 mutations are promising predictors for OS in CRLM patients after hepatectomy. Postoperative chemotherapy may significantly benefit CRLM patients with RAS mutations, particularly those identified as high-risk.

In older adolescents with ITN, the A firma GSC showed excellent performance when de fining a true negative result by histology or clinical follow-up. Our findings indicate that an A firma GSC-B result appears reassuring and may allow for a more conservative management strategy in younger patients with ITN.

The presence of recurrent RAC1 mutations in undifferentiated melanoma is also notable as these alterations may contribute to mitogen-activated protein (MAP) kinase pathway targeted therapy resistance. Furthermore, the RAC1 alterations identified in this cohort have been shown to drive a melanocytic to mesenchymal switch in melanocytes, offering a possible explanation for the undifferentiated phenotype of these melanomas.

FNA rinses are a suitable source to perform molecular analysis after morphological evaluation maximizing diagnostic efficiency. Additionally, BRAF V600E is not the sole pathogenic alteration in thyroid cancer, so expanding tests to include other molecular alterations may enhance diagnostic utility using this available material.

Lox-stop-Lox NrasQ61R mice were crossed with Prox1-CreERT2 mice expressing tamoxifen-inducible Cre recombinase specifically in LECs...These results suggest that the NRAS p.Q61R variant in LECs plays a role in development of lymphatic anomalies. While this model does not directly reflect the human pathology of GLA and KLA, there are overlapping features, suggesting that further study of this model may help in studying GLA and KLA mechanisms.

Our studies show that the NRASQ61R mutation in endothelial cells induces Ang-2 expression in vitro and in vivo. In cultured human endothelial cells, NRASQ61R drives elevated Ang-2 through MAP kinase and mTOR-dependent signaling pathways.

This cohort study found that KRAS allelic variants were relatively common and may be potentially actionable genomic alterations in patients with BTCs, especially perihilar cholangiocarcinoma and extrahepatic cholangiocarcinoma. The findings add to the growing data on genomic and immune landscapes of KRAS allelic variants in BTCs and are potentially of value to the planning of specific therapies for this heterogeneous patient group.

The study's findings indicate a rising frequency of mutations in these genes in Iran, highlighting the need to screening mutations in the main exons of all three genes for effective colorectal cancer treatment strategies.

This observation reveals a binding site that can potentially be exploited for development of inhibitors against mutant NRAS. Furthermore, the well-resolved catalytic site of this GTPase bound to native GTP provides insight into the stalled GTP hydrolysis observed for NRAS-Q61K.

However, parity decreased the overall prevalence of tumors bearing Krasmut, and the magnitude of this decrease depended on both the number and timing of pregnancies. These multistage models may be useful for elucidating biological features of premalignant mammary neoplasia.

Tunlametinib showed promising antitumor activity with a manageable safety profile in patients with advanced NRAS-mutant melanoma, including those who had prior exposure to immunotherapy. The findings warrant further validation in a randomized clinical trial.

Notably, the KRAS mutations G12D, G13D, and Q61H abrogate their association with LZTR1, thereby affecting turnover. Elucidating the implications of LZTR1-mediated regulation of KRAS protein levels in cancer may offer insights into therapeutic strategies targeting KRAS-driven malignancies.

Tumour thickness ≥ 4 mm, ulceration, the coexistence of regression and TILs, and positive BRAFV600E were risk factors for poor prognosis of CoM patients. Besides, expression level of BRAFV600E was positively correlated with the expression levels of PD-1 and PD-L1.

Therefore, the seven SNPs were identified as high-risk SNPs. Conclusions Given that SNPs have the potential to be candidates for cellular alterations brought on by mutations that are associated with cancer, this study provides vital information about how SNPs might be utilized as a diagnostic marker for cancer.

The anti-tumor effects of LY3009120 were observed in nine melanoma cell lines, indicating the potential feasibility of experimental trials with LY3009120. The present study reveals that the irradiation-resistant canine metastasis cells (cRGO1.2) harboring the NRAS p.G13R mutation are significantly LY3009120-sensitive, while the equine metastases-derived eRGO6 cells show significant resistance to LY3009120, which make them both valuable tools for studying resistance mechanisms in comparative oncology.

Patients with RAS/BRAFV600E wt mCRC according to tissue genotyping who benefited from previous anti-EGFR-based treatment (fluoropyrimidines, oxaliplatin, irinotecan, and antiangiogenics) and then experienced disease progression to EGFR targeting were eligible for screening in the PARERE trial. This is the largest prospective cohort of mCRC patients screened with LB for anti-EGFR retreatment in a randomized study. ctDNA genotyping reveals that at least one out of three patients candidate for retreatment should be excluded from this therapy, and other potential drivers of anti-EGFR resistance are found in approximately one out of three patients with RAS/BRAFV600E wt ctDNA.

P2, N=34, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Jan 2024 --> Jan 2025

A subset (10.3%) of multifocal PTCs had discordant molecular drivers and 90.0% of them were a combination of BRAF-positive and kinase gene fusion-associated PTCs, mostly with different histologic subtypes. Half of the cases had nodal metastasis and 40% (2/5) of them showed simultaneous involvement by tumors with discordant molecular drivers. These findings highlight the clinical importance of identifying such cases given the potentially different management with specific targeted therapies.

Additionally, CT2A-luc demonstrated substantial baseline secretion of the CCL-2, CCL-5, and CCL-22 chemokines, which play important roles as myeloid chemoattractants. Although the clinical contexts that can be modeled by GL261 and CT2A for huGBM are limited, CT2A may be an informative model of immunotherapy resistance due to its deficits in antigen presentation machinery and interferon response pathways.

CNS melanomas based on NCM in childhood are aggressive malignancies without curative treatment to date. Therapeutic approaches must be individualized. Genetic tumor sequencing is essential to improve understanding of tumorigenesis and potentially identify new therapeutic targets.

P1, N=120, Recruiting, InxMed (Shanghai) Co., Ltd. | Trial completion date: Jun 2024 --> Sep 2024 | Trial primary completion date: Dec 2023 --> Jun 2024

Demographic details, tumor characteristics, and 10-year outcome data were also obtained.Ten cases with BRAF V600E mutations (11.6%) and five (5.49%) NRAS mutations (4 at Q61R, 1 at Q61K) were detected. No statistically significant differences were noted between groups for age, gender, depth of invasion, nodal status, or recurrence status (p ≥ 0.05).These findings suggest that the Irish population has a markedly lower incidence of BRAF and NRAS mutations in melanoma than those reported in other cohorts.

No recurrence or carcinoma development was observed in any of the IUP cases during the follow-up period. Thus, we confirmed the importance of RAS pathway activation in IUP pathogenesis, an association between RAS family gene mutations and IUP subtypes, and the spread patterns of IUP cells within the surface.

A significant ex vivo inhibition of proliferation with the combination of roflumilast+cobimetinib was observed compared to dimethyl sulfoxyde control in both models (51 and 67%). To decipher molecular mechanisms underlying this effect, we performed transcriptomic analyses and revealed a decrease in MKI67, RAF1 and CCND1 expression under bitherapy. Our findings strengthen the therapeutic interest of PDE4 inhibitors and support further experiments to evaluate this approach in metastatic melanoma.

Conclusion  This constitutes one of the few reports on comprehensive analysis of molecular alterations underlying melanomas in Indian patients. A larger sample size, with more extensive molecular markers, would yield additional information on the disease manifestation.

Finally, we predict binding and provide structural models of NRAS antigens spanning the entire HLA allelic landscape, together with in vitro validation for HLA-A*01:191, HLA-B*15:01, and HLA-C*08:02. Our work provides a basis to delineate the solution surface features and immunogenicity of clinically relevant neoepitope/HLA targets for cancer therapy.

In our Brazilian cohort of mCRC patients, frequencies of RAS and BRAF mutations were similar to worldwide data. However, we found lower than expected frequency of MSI-high tumors. KRAS G12C mutation was associated with early-onset mCRC, an emergent population in which KRAS G12C inhibitors might be particulary useful.

PTPN11 and NRAS were the most frequent mutations and RTK-RAS signaling pathway was the most involved pathway in rare AML patients with t(16; 21)(p11; q22)/ FUS: : ERG. The addition of signaling pathway inhibitors followed by HSCT might be an effective strategy to overcome the dismal outcome of this subtype. Larger cohort studies are warranted to investigate the molecular characteristics further as well as evaluate the clinical activity of the SHP2 (PTPN11) inhibitors in FUS: : ERG AML patients.

Twenty tested cases showed retained SMARCA4 expression. We conclude that ATCs express a number of divergent lineage markers that can cause diagnostic dilemmas, as they are also features of other tumors in the differential diagnosis of high-grade midline neck malignancies.

These findings suggest convergent genomic evolution in the MAPK pathway may be a potential mechanism of acquired resistance to FGFRi.

In addition to well-characterized MM drivers (KRAS, NRAS, etc.), 16 new candidate genes were found significantly mutated, including IKFZ3 (Aiolos), a transcription factor and direct target of degradation with lenalidomide therapy, harboring frameshift and stop-gain mutations in the protein dimerization domain which could affect complete differentiation of plasma cells...Conclusion These results highlight the power of genomic profiling in MM for early detection, discovery of novel drivers, monitoring of clonal selection and transformation to malignant disease. We show SMM is not a simple genomically-mature disorder, but rather a dynamic state with competing subclones, which could be leveraged for therapeutic interventions.

RMC-7977 is a potent, oral small molecule inhibitor of both wild-type and mutant GTP-bound RAS oncoproteins (RASMULTI) and is a preclinical tool compound representative of the clinical candidate RMC-6236, currently in clinical evaluation (NCT05379985)...Gilteritinib and the gilteritinib/venetoclax combination selected for survival of cells harboring NRAS mutations, but RMC-7977 inhibited outgrowth of all cell populations...In vivo studies investigating the tolerability and activity of RMC-7977 and RMC-7977 combinations in RAS mutant/FLT3i-resistant patient-derived xenograft models are ongoing and will be presented. Collectively, our data provide preclinical evidence that combination therapies leveraging RASMULTI(ON) inhibition are effective in suppressing RAS-mutant AML clones, a common mechanism of resistance to currently approved targeted therapies in AML and a current area of high unmet clinical need.