Rat Sarcoma Viral Oncogene Homolog Research Articles

More powerful dysregulation of Helicobacter pylori East Asian-type CagA on intracellular signalings.

Chronic infection by Helicobacter pylori strains expressing cytotoxin-associated gene A (CagA) are the strongest risk factor for gastric cancer. CagA can be classified into East Asian-type and Western-type (CagAE and CagAW), with CagAE being more closely associated with gastric cancer. This study aimed to investigate the impact of CagAE on intracellular signaling pathways to explain its high oncogenicity. Mutant H. pylori strains expressing either CagAE or CagAW were generated by transforming CagAE/W-expression plasmid into CagA-deleted G27 strain (G27ΔCagA). In human gastric epithelial cells (GES-1) infection, CagAE induced more severe cytopathic changes, including higher interleukin-8 (IL-8) secretion, reduced cell viability, more pronounced "hummingbird phenotype" alterations, and increased cell migration and invasion compared to CagAW. Transcriptome analysis revealed that CagAE had a stronger effect on the up-regulation of key intracellular processes, including tumor necrosis factor-ɑ (TNF-ɑ) signal pathway via nuclear factor kappa-B (NF-κB), inflammatory response, interferon-γ (IFN-γ) response, hypoxia, ultraviolet (UV) response, and Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) signaling. A significant upregulation of hypoxia-related genes was a notable feature of CagAE. GES-1 cells infected with CagAE exhibited more severe intracellular hypoxia and higher levels of reactive oxygen species (ROS) than those infected with CagAW. Inhibition of hypoxia-inducible factor-1α (HIF-1α), which blocks hypoxia signaling, mitigated CagAE-induced cell migration, emphasizing the role of hypoxia in mediating CagAE effects. The study provides transcriptome evidence of CagA-associated intracellular regulation during H. pylori infection, demonstrating that CagAE exerts stronger effects on intracellular signaling than CagAW. These findings offer insights into the heightened carcinogenic potential of CagAE in H. pylori-induced gastric cancer.

Oncogenic KRAS mutations modulate BAX-mediated cell death

Kirsten rat sarcoma viral oncogene homolog (KRAS) belongs to the GTPase RAS superfamily, which regulates several cell-signaling pathways involved in the control of important cellular functions, including apoptosis. Oncogenic mutations in KRAS are considered the most common gain-of-function mutations, affecting 30–50 % of colorectal cancer (CRC) patients. While RAS proteins usually play an anti-apoptotic role, little is known about the involvement of KRAS mutations in apoptosis regulation. Here, we aimed to elucidate the role of mutated human KRAS in the regulation of BAX, a key pro-apoptotic member of the Bcl-2 family. For this purpose, we took advantage of the simpler yeast model Saccharomyces cerevisiae, using cells deficient in the main yeast RAS isoform (ras2Δ) co-expressing wild-type KRAS (KRASWT) or the most frequent KRAS mutations found in CRC - KRASG12D, KRASG12V or KRASG13D, along with human BAX. We show that, in comparison with KRASWT, KRAS mutants confer resistance to BAX-induced death and cytochrome c (cyt c) release. The modulation of BAX by KRAS isoforms seems to result from a direct interaction between these proteins, as they co-localize at the mitochondria and there is evidence they may physically interact. We further show that acetic acid significantly increased cell death in cells expressing BAX and co-expressing oncogenic KRAS mutants, but not KRASWT. This suggests a potential mechanism explaining the increased sensitivity of CRC cells harboring a KRAS-activated pathway to acetate. These findings contribute to a clearer understanding of how KRAS regulate BAX function, a relevant aspect in tumor progression.

Exploring the potential mechanisms of polysaccharides against gastric ulcer: Network pharmacology analysis and molecular docking validation

AbstractGastric ulcer is a common peptic ulcer that affects human health and life quality seriously. As anti‐gastric ulcer drugs usually cause side‐effects, polysaccharides may be the potential alternatives because of better effectiveness and less toxicity. Although the anti‐gastric ulcer activities of polysaccharides have been widely reported, the mechanisms have not yet been well‐disclosed. In this study, network pharmacology analysis was performed to explore the potential mechanisms of polysaccharides against gastric ulcer, and the results were validated by molecular docking. Results indicated that β‐glucan, arabinogalactan, xylan, and arabinan were the key structures, and ABL1, AKT1, androgen receptor, epidermal growth factor receptor, v‐Ha‐ras Harvey rat sarcoma viral oncogene homolog, HSP90AA1, mitogen‐activated protein kinase 8 (MAPK8), MAPK14, NOS2, PIK3R1, RAC1, ras homolog gene family member A, and proto‐oncogene tyrosine‐protein kinase Src were the core targets for polysaccharides in treating gastric ulcer. Polysaccharides have influences on 1958 GO items and 199 KEGG pathways, and their anti‐gastric ulcer activities are related to MAPK, Ras, PI3K‐Akt, vascular endothelial growth factor, prolactin, FoxO and Rap1 signaling pathways, etc. Molecular docking validation showed that the results of network pharmacology analysis were credible, and interactions between polysaccharide structures and core targets were observed. This study contributes to understanding the mechanisms of polysaccharides in treating gastric ulcer and provides references for future activity screening and mechanism research in anti‐gastric ulcer.

The pan-cancer landscape of crosstalk between leukocyte transendothelial migration-related genes and tumor microenvironment relevant to prognosis and immunotherapy response.

Leukocyte transendothelial migration-related genes (LTEMGs) play a crucial role in the immune response and have been extensively studied in various pathological conditions, including inflammation, infection, and cancer. In recent years, increasing attention has been given to understanding the biological mechanisms of LTEMGs in the context of tumor progression and metastasis. The potential function of LTEMGs in cancer progression remains unclear. The aim of this study is to systematically delineate the relationship between LTEMGs and tumor prognosis and immune microenvironment at the pan-cancer level, providing new biomarkers for personalized immunotherapy. The gene alteration, messenger RNA (mRNA) expression, and prognostic value of LTEMGs in pan-cancer were evaluated using Bulk and single-cell RNA (scRNA) sequence data. The LTEMGs score was calculated by R package "GSVA". The association of LTEMGs score with tumor microenvironment and immunotherapy response were deeply explored. We assessed the mRNA expression of 114 LTEMGs across various cancers, finding significant upregulation in acute myeloid leukemia (LAML) and pancreatic adenocarcinoma (PAAD). Prognostic analysis indicated most LTEMGs were risk factors in low-grade glioma (LGG), PAAD, uveal melanoma (UVM), and LAML. The LTEMGs score, highest in kidney renal clear cell carcinoma (KIRC) and lowest in UVM, was higher in tumor tissues compared to normal tissues in several cancers. The score was a risk factor for overall survival (OS) in LGG, UVM, and others, but protective in KIRC and some others. LTEMGs score correlated positively with Kirsten rat sarcoma viral oncogene homolog (KRAS) signaling, apoptosis, and immune responses. It also correlated with immune and stromal scores, and immune-related pathways. Higher LTEMGs score was linked to greater immune cell infiltration and poorer immunotherapy outcomes. Single-cell analysis revealed higher LTEMGs score in endothelial and monocyte cells, consistent with reduced immunotherapy responsiveness. Our results reveal that LTEMGs are closely associated with tumor microenvironment. Patients with high LTEMGs score might be resistant to immunotherapy.

Adagrasib in KRYSTAL-12has Broken the KRAS G12C Enigma Code in Non-Small Cell Lung Carcinoma.

Kirsten rat sarcoma viral oncogene homolog (KRAS) G12C-mutant non-small cell lung carcinoma (NSCLC) accounts for approximately 10-13% of advanced nonsquamous NSCLC cases in Western populations, presenting a significant therapeutic challenge owing to the difficulty of directly targeting KRAS. Adagrasib, an oral small-molecule covalent inhibitor, irreversibly and selectively targets KRASG12C in its inactive state. It received accelerated Food and Drug Administration (FDA) approval on December 12, 2022, following the KRYSTAL-1 Phase II trial. The Phase III KRYSTAL-12 trial demonstrated that adagrasib significantly improved median progression-free survival (mPFS) compared with docetaxel (HR, 0.58; 95% CI: 0.45-0.76; P<0.0001) and increased the intracranial objective response rate (ORR) to 40% in the central nervous system (CNS) evaluable population. This paper evaluates the clinical efficacy of adagrasib in KRAS G12C-mutated advanced NSCLC discussing its potential advantages over other inhibitors such as sotorasib. Despite not reaching the 6-month mPFS benchmark, adagrasib offers significant clinical benefits, particularly for the management of CNS metastases. In this pros and cons debate, we argue that adagrasib has broken the KRAS G12C enigma code in NSCLC.

Identification of CDH4 Gene Copy Number Alteration and Its Association with Clinical Profile of Colorectal Cancer Patient

Background: The genes cadherin 4 (CDH4), Kirsten rat sarcoma viral oncogene homolog (KRAS), V-Raf murine sarcoma viral oncogene homolog B (BRAF), and microsatellite instability (MSI) each play a role in the development of colorectal cancer (CRC). CDH4 gene is located in chromosome 20q13.33 and its amplification or gain is the earliest mutational event found in the majority of CRC and colon polyps. This study aimed to identify copy number alteration in the CDH4 gene and its association with the clinical profile of CRC patients, including gender, age, tumor location and differentiation, frequency of BRAF and KRAS mutations, and MSI status. Methods: The DNA was extracted from 50 tumors and adjacent normal tissues based on the manufacturer’s instructions. Detection of MSI status was carried out by pentaplex polymerase chain reaction (PCR) and PCR products were size separated by capillary electrophoresis (CE) using an ABI 310 Genetic Analyzer. Both KRAS and BRAF mutations were identified by PCR and sequencing while CDH4 copy measurement was measured using TaqManTM Copy Number Assay. Results: Our findings showed 22 (44%) samples with no changes in the copy number of CDH4 gene. Interestingly, 21 (42%) cases had an amplification of the CDH4 gene or CDH4 gene gain, and seven (14%) cases decreased in CDH4 gene expression or CDH4 gene loss. We found an association between changes in the CDH4 gene and gender (p=0.001). However, there was no association between changes in the CDH4 gene and age (p=0.979), tumor location (p=0.145) and differentiation (p=0.648), the frequency of BRAF (p=0.171) and KRAS mutations (p=0.184) and MSI status (p=0.923). Conclusions: Copy number alteration in CDH4 gene in CRC patients and this alteration is significantly associated with gender. Further studies with a larger number of samples are essential to confirm this result and to identify the cause of CDH4 copy number alteration and its biological significance.

Yap methylation-induced FGL1 expression suppresses anti-tumor immunity and promotes tumor progression in KRAS-driven lung adenocarcinoma.

Despite significant strides in lung cancer immunotherapy, the response rates for Kirsten rat sarcoma viral oncogene homolog (KRAS)-driven lung adenocarcinoma (LUAD) patients remain limited. Fibrinogen-like protein 1 (FGL1) is a newly identified immune checkpoint target, and the study of related resistance mechanisms is crucial for improving the treatment outcomes of LUAD patients. This study aimed to elucidate the potential mechanism by which FGL1 regulates the tumor microenvironment in KRAS-mutated cancer. The expression levels of FGL1 and SET1 histone methyltransferase (SET1A) in lung cancer were assessed using public databases and clinical samples. Lentiviruses were constructed for transduction to overexpress or silence FGL1 in lung cancer cells and mouse models. The effects of FGL1 and Yes-associated protein (Yap) on the immunoreactivity of cytotoxic T cells in tumor tissues were evaluated using immunofluorescence staining and flow cytometry. Chromatin immunoprecipitation and dual luciferase reporter assays were used to study the SET1A-directed transcriptional program. Upregulation of FGL1 expression in KRAS-mutated cancer was inversely correlated with the infiltration of CD8+ T cells. Mechanistically, KRAS activated extracellular signal-regulated kinase 1/2 (ERK1/2), which subsequently phosphorylated SET1A and increased its stability and nuclear localization. SET1A-mediated methylation of Yap led to Yap sequestration in the nucleus, thereby promoting Yap-induced transcription of FGL1 and immune evasion in KRAS-driven LUAD. Notably, dual blockade of programmed cell death-1 (PD-1) and FGL1 further increased the therapeutic efficacy of anti-PD-1 immunotherapy in LUAD patients. FGL1 could be used as a diagnostic biomarker of KRAS-mutated lung cancer, and targeting the Yap-FGL1 axis could increase the efficacy of anti-PD-1 immunotherapy.

Rapid and unbiased enrichment of extracellular vesicles via a meticulously engineered peptide

Extracellular vesicles (EVs) have garnered significant attention in biomedical applications. However, the rapid, efficient, and unbiased separation of EVs from complex biological fluids remains a challenge due to their heterogeneity and low abundance in biofluids. Herein, we report a novel approach to reconfigure and modify an artificial insertion peptide for the unbiased and rapid isolation of EVs in 20 min with ∼80% recovery in neutral conditions. Moreover, the approach demonstrates exceptional anti-interference capability and achieves a high purity of EVs comparable to standard ultracentrifugation and other methods. Importantly, the isolated EVs could be directly applied for downstream protein and nucleic acid analyses, including proteomics analysis, exome sequencing analysis, as well as the detection of both epidermal growth factor receptor (EGFR) and V-Ki-ras2 Kirsten Rat Sarcoma Viral Oncogene Homologue (KRAS) gene mutation in clinical plasma samples. Our approach offers great possibilities for utilizing EVs in liquid biopsy, as well as in various other biomedical applications.

Targeting cancer with small-molecule pan-KRAS degraders

Mutations in the Kirsten rat sarcoma viral oncogene homolog (KRAS) protein are highly prevalent in cancer. However, small-molecule concepts that address oncogenic KRAS alleles remain elusive beyond replacing glycine at position 12 with cysteine (G12C), which is clinically drugged through covalent inhibitors. Guided by biophysical and structural studies of ternary complexes, we designed a heterobifunctional small molecule that potently degrades 13 out of 17 of the most prevalent oncogenic KRAS alleles. Compared with inhibition, KRAS degradation results in more profound and sustained pathway modulation across a broad range of KRAS mutant cell lines, killing cancer cells while sparing models without genetic KRAS aberrations. Pharmacological degradation of oncogenic KRAS was tolerated and led to tumor regression in vivo. Together, these findings unveil a new path toward addressing KRAS-driven cancers with small-molecule degraders.

Research into overcoming drug resistance in lung cancer treatment using CRISPR-Cas9 technology: a narrative review.

Lung cancer remains a leading cause of cancer-related mortality globally, with drug resistance posing a significant challenge to effective treatment. The advent of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (CRISPR-Cas9) technology offers a novel and precise gene-editing technology for targeting and negating drug resistance mechanisms in lung cancer. This review summarizes the research progress in the use of CRISPR-Cas9 technology for investigating and managing drug resistance in lung cancer treatment. A literature search was conducted using the Web of Science and PubMed databases, with the following keywords: [CRISPR-Cas9], [lung cancer], [drug resistance], [gene editing], and [gene therapy]. The search was limited to articles published in English from 2002 to September 2023. From the search results, studies that utilized CRISPR-Cas9 technology in the context of lung cancer drug resistance were selected for further analysis and summarize. CRISPR-Cas9 technology enables precise DNA-sequence editing, allowing for the targeted addition, deletion, or modification of genes. It has been applied to investigate drug resistance in lung cancer by focusing on key genes such as epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), tumor protein 53 (TP53), and B-cell lymphoma/leukemia-2 (BCL2), among others. The technology has shown potential in inhibiting tumor growth, repairing mutations, and enhancing the sensitivity of cancer cells to chemotherapy. Additionally, CRISPR-Cas9 has been used to identify novel key genes and molecular mechanisms contributing to drug resistance, offering new avenues for therapeutic intervention. The review also highlights the use of CRISPR-Cas9 in targeting immune escape mechanisms and the development of strategies to improve drug sensitivity. The CRISPR-Cas9 technology holds great promise for advancing lung cancer treatment, particularly in addressing drug resistance. The ability to precisely target and edit genes involved in resistance pathways offers a powerful tool for developing more effective and personalized therapies. While challenges remain in terms of delivery, safety, and ethical considerations, ongoing research and technological refinements are expected to further enhance the role of CRISPR-Cas9 in improving patient outcomes in lung cancer treatment.

Insight of the molecular mechanism of inhibitors located at different allosteric sites regulating the activity of wild type and mutant KRAS (G12)

As the important hub of many cellular signaling networks, KRAS (Kirsten rat sarcoma viral oncogene homologue) has been identified as a tumor biomarker. It is the frequently mutated oncogene in human cancers, and KRAS protein activation caused by mutations, such as G12D, has been found in many human tumors tissues. Although, there are two specific allosteric sites (AS1 and AS2) on the KRAS protein that can be used as the targets for inhibitor development, the difference of regulatory mechanisms between two individual allosteric sites still not be reported. Here, using molecular dynamics simulations combined with molecular mechanics generalized born surface area (MM/GBSA) analysis, we found that both of the inhibitors, located at AS1 and AS2, were able to reduce the binding free energy between wild type, mutant KRAS (G12/D/V/S/C) and GTP remarkably, however the effect of inhibitors on the binding free energy between wild type, mutant KRAS and GDP was limited. In addition, the degree of decrease of binding free energy between KRAS and GTP caused by inhibitors at AS2 was significantly greater than that caused by inhibitors at AS1. Further analysis revealed that both inhibitors at AS1 and AS2 were able to regulate the fluctuation of Switch Ⅰ and Switch Ⅱ to expand the pocket of the orthosteric site (GTP binding site), thereby reducing the binding of KRAS to GTP. Noteworthy there was significant differences in the regulatory preferences on Switch Ⅰ and Switch Ⅱ between two type inhibitor. The inhibitor at AS2 mainly regulated Switch Ⅱ to affect the pocket of the orthosteric site, while the inhibitor at AS1 mainly expand the pocket of the orthosteric site by regulating the fluctuation of Switch Ⅰ. Our study compared the differences between two type inhibitors in regulating the KRAS protein activity and revealed the advantages of the AS2 as the small molecule drug target, aiming to provide theoretical guidance for the research of novel KRAS protein inhibitors.

A real-world pharmacovigilance study of KRAS G12C mutation inhibitors based on the food and drug administration adverse event reporting system.

Sotorasib and adagrasib have been widely used for the non-small cell lung cancer (NSCLC) patients harboring Kirsten rat sarcoma viral oncogene homolog (KRAS) G12C mutation. It's necessary to assess their safety profiles in the real-world population. A retrospective pharmacovigilance was conducted to examine adverse events (AEs) associated with sotorasib and adagrasib therapies using the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). Disproportionality analysis was performed employing Venn analysis and four data-mining algorithms, including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS). The most commonly reported system organ classes (SOCs) for both adagrasib and sororasib were general, gastrointestinal, and investigations disorders. Notably, sotorasib exhibited significant signals for neoplasms and hepatobiliary disorders in four algorithms. Specifically, AEs related to neoplasms were predominantly associated with lung malignancies, all of which were consistent with the therapeutic indications of KRAS G12C mutation inhibitor. A total of 19 common AEs were identified in sotorasib and adagrasib, spanning gastrointestinal, general, hepatobiliary, investigations, metabolism, musculoskeletal, neoplasms, and respiratory disorders. 4 severe AEs (SAEs) were identified in sotorasib, with 3 SAEs displaying significant signals in four algorithms, including drug-induced liver injury, pancreatitis, and hepatic failure. In adagrasib, only 2 SAEs were detected, with renal failure showing significant signals in four algorithms. This study offers a comprehensive evaluation of the major safety signals associated with sotorasib and adagrasib, providing valuable information for clinicians regarding drug selection and safety considerations, thereby facilitating the design of future prospective safety studies.

Pulmonary Adenocarcinoma with Enteric Differentiation without TTF-1 Expression Is a Very Rare Subtype with Limited Treatment Options and Poor Prognosis

Plain Language SummaryPulmonary adenocarcinoma with enteric differentiation (PAED) without expression of thyroid transcription factor-1 (TTF-1) is an extremely rare and hard-to-treat variant of lung cancer. We collected clinicopathological data of 121 Caucasian patients with pulmonary adenocarcinoma without TTF-1 expression, their systemic therapy options, and the efficacy of their systemic treatment including 79 cases without a PAED and 42 cases with a PAED, compared these subgroups, and investigated patients’ response to chemotherapy and immunotherapy as first-line treatment. A comparison of clinicopathological data of TTF-1-negative PAED and non-PAED patients revealed a significantly lower frequency of high programmed death receptor ligand 1 (PD-L1) expression in PAED resulting in the lack of single-agent immunotherapy (p = 0.032) in this subgroup. Frequencies of an activating Kirsten rat sarcoma viral oncogene homolog (KRAS) gene mutation were high in both groups (46.7% and 50.0%), but a G12C gene mutation was seldomly noted (in 6.7% and 18.5% of patients with evaluable data). Median overall survival (OS) was poor in both groups (10 and 12 months). The majority of PAED patients received platinum-based and taxane-containing chemotherapy or chemo-/immunotherapy with an objective response rate of 31.6% and a disease control rate of 57.9%. Median progression-free survival (PFS) and OS of PAED patients with systemic therapy were very poor (3.9 months and 5.9 months). Caucasian patients with a TTF-1-negative PAED have a poor prognosis with reduced response rates to standard first-line systemic therapy and short survival times (PFS and OS).

Assessment of prognostic indicators and KRAS mutations in rectal cancer using a fractional-order calculus MR diffusion model: whole tumor histogram analysis.

This study aims to explore the relationship between apparent diffusion coefficient (ADC) and fractional-order calculus (FROC)-specific parameters with prognostic indicators and Kirsten rat sarcoma viral oncogene homologue (KRAS) mutation status in rectal cancer. One hundred fifty-eight patients with rectal cancer were retrospectively enrolled. Histogram measurements of ADC, diffusion coefficient (D), intravoxel diffusion heterogeneity (β), and a microstructural quantity (μ) were estimated for the whole-tumor volume. The relationships between histogram measurements and prognostic indicators were evaluated. The efficacy of histogram measurements, both conducted singly and in conjunction, for evaluating different KRAS mutation statuses was also assessed. The performance of mean and median histogram measurements in evaluating various KRAS mutation statuses was assessed using Receiver Operating Characteristic (ROC) curve analysis. A p-value of less than 0.05 was considered statistically significant. The histogram measurements of ADC, D, β, and μ differed significantly between well-moderately differentiated groups and poorly differentiated groups, T1-2 and T3-4 subgroups, lymph node metastasis (LNM)-negative and LNM-positive subgroups, extranodal extension (ENE)-negative and ENE-positive subgroups, tumor deposit (TD)-negative and TD-positive subgroups, and lymphovascular invasion (LVI)-negative and LVI-positive subgroups. The combination of Dmean, βmean, and μmean achieved the highest performance [The area under the ROC curve (AUC) = 0.904] in evaluating the KRAS mutation status. When assessing parameters from the FROC model as potential biomarkers through histograms, they surpass traditional ADC values in distinguishing prognostic indicators and determining KRAS mutation status in rectal cancer.

Targeting Smurf1 to block PDK1-Akt signaling in KRAS-mutated colorectal cancer.

The phosphoinositide 3-kinase (PI3K)-Akt axis is one of the most frequently activated pathways and is demonstrated as a therapeutic target in Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutated colorectal cancer (CRC). Targeting the PI3K-Akt pathway has been a challenging undertaking through the decades. Here we unveiled an essential role of E3 ligase SMAD ubiquitylation regulatory factor 1 (Smurf1)-mediated phosphoinositide-dependent protein kinase 1 (PDK1) neddylation in PI3K-Akt signaling and tumorigenesis. Upon growth factor stimulation, Smurf1 immediately triggers PDK1 neddylation and the poly-neural precursor cell expressed developmentally downregulated protein 8 (poly-Nedd8) chains recruit methyltransferase SET domain bifurcated histone lysine methyltransferase 1 (SETDB1). The cytoplasmic complex of PDK1 assembled with Smurf1 and SETDB1 (cCOMPASS) consisting of PDK1, Smurf1 and SETDB1 directs Akt membrane attachment and T308 phosphorylation. Smurf1 deficiency dramatically reduces CRC tumorigenesis in a genetic mouse model. Furthermore, we developed a highly selective Smurf1 degrader, Smurf1-antagonizing repressor of tumor 1, which exhibits efficient PDK1-Akt blockade and potent tumor suppression alone or combined with PDK1 inhibitor in KRAS-mutated CRC. The findings presented here unveil previously unrecognized roles of PDK1 neddylation and offer a potential strategy for targeting the PI3K-Akt pathway and KRAS mutant cancer therapy.

CALU promotes lung adenocarcinoma progression by enhancing cell proliferation, migration and invasion

BackgroundLung cancer is the second most common cancer with the highest mortality in the world. Calumenin as a molecular chaperone that not only binds various proteins within the endoplasmic reticulum but also plays crucial roles in diverse processes associated with tumor development. However, the regulatory mechanism of calumenin in lung adenocarcinoma remains elusive. Here, we studied the impact of calumenin on lung adenocarcinoma and explored possible mechanisms.Methods5-ethynyl-2’-deoxyuridine assay, colony formation, transwell and wound healing assays were performed to explore the effects of calumenin on the proliferation and migration of lung adenocarcinoma cells. To gain insights into the underlying mechanisms through which calumenin knockdown inhibits the migration and proliferation of lung adenocarcinoma, we performed Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, Gene Set Enrichment Analysis and Ingenuity Pathway Analysis based on transcriptomics by comparing calumenin knockdown with normal A549 cells.ResultsThe mRNA and protein levels of calumenin in lung adenocarcinoma are highly expressed and they are related to an unfavorable prognosis in this disease. Calumenin enhances the proliferation and migration of A549 and H1299 cells. Gene Set Enrichment Analysis revealed that knockdown of calumenin in A549 cells significantly inhibited MYC and V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog signaling pathways while activating interferon signals, inflammatory signals, and p53 pathways. Ingenuity pathway analysis provided additional insights, indicating that the interferon and inflammatory pathways were prominently activated upon calumenin knockdown in A549 cells.ConclusionsThe anti-cancer mechanism of calumenin knockdown might be related to the inhibition of MYC and KRAS signals but the activation of interferon signals, inflammatory signals and p53 pathways.

Stability and expression of K-ras mimotopes in freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder during storage in vacuum packaging.

This study aims to evaluate the storage stability of the freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder expressing K-ras (Kristen rat sarcoma viral oncogene homolog) mimotopes targeting colorectal cancer in vacuum packaging. The freeze-dried L. lactis-fermented milk powder stored in 4-ply retortable polypropylene (RCPP)-polyamide (PA)-aluminium (AL)-polyethylene terephthalate (PET) and aluminium polyethylene (ALPE) was evaluated throughout 49 days of accelerated storage (38°C and 90% relative humidity). The fermented milk powder stored in 4-ply packaging remained above 6 log10 CFU g-1 viability, displayed lower moisture content (6.1%), higher flowability (43° angle of repose), water solubility (62%), and survivability of L. lactis after simulated gastric and intestinal digestion (>82%) than ALPE packaging after 42 days of accelerated storage. K-ras mimotope expression was detected intracellularly and extracellularly in the freeze-dried L. lactis-fermented milk powder upon storage. This suggests that fermented milk powder is a suitable food carrier for this live oral vaccine.

Overview of the Role of Liquid Biopsy in Non-small Cell Lung Cancer (NSCLC)

Solid tumour tissue has traditionally been used for cancer molecular diagnostics. Recently, biomarker assessment in blood or liquid biopsies has become relevant because it allows genotyping in a less invasive and costly manner. In addition, it is a very useful technique in cases with insufficient tumour samples.Recent data have shown that this method can provide the baseline molecular characteristics of the tumour and resistance changes that emerge during cancer treatment. In terms of diagnostic application, the platforms available for clinical use in lung cancer focus on the isolation and detection of circulating DNA (ctDNA) and generally cover a limited number of mutations in genes such as epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS) and BRAF, as well as anaplastic lymphoma kinase (ALK) rearrangements. In parallel, there are plasma genotyping platforms based on next-generation sequencing (NGS) techniques, which are much broader in scope, allowing multiple genes to be studied simultaneously in a more efficient manner.More recently, promising research scenarios for liquid biopsy have emerged, such as its utility for early diagnosis and evaluation of minimal residual disease after oncological treatment.In light of these advances, knowledge of the benefits and limitations of liquid biopsy, as well as awareness of emerging information on new indications for this technique in non-small cell lung cancer (NSCLC), are of paramount importance in developing more effective management strategies for patients with this neoplasm.

The Target Therapy Hyperbole: "KRAS (p.G12C)"-The Simplification of a Complex Biological Problem.

Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) gene variations are linked to the development of numerous cancers, including non-small cell lung cancer (NSCLC), colorectal cancer (CRC), and pancreatic ductal adenocarcinoma (PDAC). The lack of typical drug-binding sites has long hampered the discovery of therapeutic drugs targeting KRAS. Since "CodeBreaK 100" demonstrated Sotorasib's early safety and efficacy and led to its approval, especially in the treatment of non-small cell lung cancer (NSCLC), the subsequent identification of specific inhibitors for the p.G12C mutation has offered hope. However, the CodeBreaK 200 study found no significant difference in overall survival (OS) between patients treated with Docetaxel and Sotorasib (AMG 510), adding another degree of complexity to this ongoing challenge. The current study compares the three-dimensional structures of the two major KRAS isoforms, KRAS4A and KRAS4B. It also investigates the probable structural changes caused by the three major mutations (p.G12C, p.G12D, and p.G12V) within Sotorasib's pocket domain. The computational analysis demonstrates that the wild-type and mutant isoforms have distinct aggregation propensities, resulting in the creation of alternate oligomeric configurations. This study highlights the increased complexity of the biological issue of using KRAS as a therapeutic target. The present study stresses the need for a better understanding of the structural dynamics of KRAS and its mutations to design more effective therapeutic approaches. It also emphasizes the potential of computational approaches to shed light on the complicated molecular pathways that drive KRAS-mediated oncogenesis. This study adds to the ongoing efforts to address the therapeutic hurdles presented by KRAS in cancer treatment.

Peniapyrones A-I, Cytotoxic Tricyclic-Fused α-Pyrone Derivatives from an Endophytic Penicillium brefeldianum F4a.

Five cyclopenta[d]pyrano[4,3-b]pyran-1,7(6H)-dione 6/6/5-fused tricyclic ring system containing metabolites peniapyrones A-E (1-5), and four previously undescribed cyclopenta[4,5]furo[3,2-c]pyran-1-one 6/5/5-fused tricyclic ring system containing compounds peniapyrones F-I (6-9), were isolated from the endophytic Penicillium brefeldianum F4a. Their structures, including absolute configurations, were determined through spectroscopic analysis and quantum chemical calculations. Peniapyrones D (4) and E (5) were a pair of diastereoisomers. Compounds 1, 3, and 5-9 showed cytotoxic activity against AsPC-1, CRL-2234, and MCF-7 cancer cell lines. Compounds 1, 3, 6, 8, and 9 inhibited the Kirsten rat sarcoma viral oncogene homologue (KRAS) mutant AsPC-1 cell line.