Relationships among KRAS mutation status, expression of RAS pathway signaling molecules, and clinicopathological features and prognosis of patients with colorectal cancer

BACKGROUND The RAS/RAF/MEK/ERK and PI3 K/AKT/mTOR signaling pathways all belong to mitogen-activated protein kinase(MAPK) signaling pathways, Mutations in any one of the upstream genes(such as the RAS gene or the BRAF gene) may be transmitted to the protein through transcription or translation, resulting in abnormal activation of the signaling pathway. This study investigated the relationship between the KRAS gene mutation and the clinicopathological features and prognosis of colorectal cancer(CRC), and the effect of KRAS mutations on its associated proteins in CRC, with an aim to clarify the cause of tumor progression and drug resistance caused by mutation of the KRAS gene.AIM To investigate the KRAS gene and RAS pathway signaling molecules in CRC and to analyze their relationship with clinicopathological features and prognosis METHODS Colorectal cancer tissue specimens from 196 patients were analyzed for KRAS mutations using quantitative polymerase chain reaction and for KRAS, BRAF,MEK, and ERK protein expression levels using immunohistochemistry of tumor microarrays. To analyze differences of RAS pathway signaling molecule expression levels in different KRAS gene status, the relationships between these parameters and clinicopathological features, 4-year progression-free survival, and overall survival were analyzed by independent sample t test, Kaplan-Meier plots,and the log-rank test. Predictors of overall and disease-free survival were assessed using a Cox proportional hazards model.RESULTS Of the 196 patients, 62(32%) carried mutations in codon 12(53/62) or codon 13(9/62) in exon 2 of the KRAS gene. KRAS, BRAF, ERK, and MEK protein expression was detected in 71.4%, 78.8%, 64.3%, and 50.8% of CRC tissues,respectively. There were no significant differences between KRAS mutation status and KRAS, BRAF, MEK, or ERK protein levels. Positive expression of KRAS and ERK was associated with poor tumor differentiation, and KRAS expression was also associated with age < 56 years. MEK expression was significantly associated with distant metastasis(P < 0.05). The 4-year progression-free survival rate, but not overall survival rate, was significantly higher in patients with KRAS-negative tumors than in those with KRAS-positive tumors(P < 0.05), whereas BRAF, MEK,and ERK expression was unrelated to survival. Multivariate analysis showed that only the expression of KRAS protein was a risk factor for tumor recurrence(P <0.05). No other clinicopathological factors correlated with KRAS, BRAF, MEK, or ERK expression.CONCLUSION KRAS gene mutations do not affect downstream protein expression in CRC.KRAS protein is associated with poor tumor differentiation, older age, and a risk of tumor recurrence.

Novel dual inhibitor for targeting PIM1 and FGFR1 kinases inhibits colorectal cancer growth in vitro and patient-derived xenografts in vivo

Colorectal cancer(CRC) is the second most common cause of cancer-related death in the world. The pro-viral integration site for Moloney murine leukemia virus 1(PIM1) is a proto-oncogene and belongs to the serine/threonine kinase family, which are involved in cell proliferation, migration,and apoptosis. Fibroblast growth factor receptor 1(FGFR1) is a tyrosine kinase that has been implicated in cell proliferation, differentiation and migration. Small molecule HCI-48 is a derivative of chalcone, a class of compounds known to possess anti-tumor, anti-inflammatory and antibacterial effects. However,the underlying mechanism of chalcones against colorectal cancer remains unclear. This study reports that HCI-48 mainly targets PIM1 and FGFR1 kinases, thereby eliciting antitumor effects on colorectal cancer growth in vitro and in vivo. HCI-48 inhibited the activity of both PIM1 and FGFR1 kinases in an ATPdependent manner, as revealed by computational docking models. Cell-based assays showed that HCI-48inhibited cell proliferation in CRC cells(HCT-15, DLD1, HCT-116 and SW620), and induced cell cycle arrest in the G2/M phase through modulation of cyclin A2. HCI-48 also induced cellular apoptosis, as evidenced by an increase in the expression of apoptosis biomarkers such as cleaved PARP, cleaved caspase 3 and cleaved caspase 7. Moreover, HCI-48 attenuated the activation of downstream components of the PIM1 and FGFR1 signaling pathways. Using patient-derived xenograft(PDX) murine tumor models,we found that treatment with HCI-48 diminished the PDX tumor growth of implanted CRC tissue expressing high protein levels of PIM1 and FGFR1. This study suggests that the inhibitory effect of HCI-48 on colorectal tumor growth is mainly mediated through the dual-targeting of PIM1 and FGFR1kinases. This work provides a theoretical basis for the future application of HCI-48 in the treatment of clinical CRC.

Highlights of recent cancer research

1 Introduction Over the past few months,there has been significant progress in the cancer research field.This article intends to present a brief review of representative breakthroughs.

Ribonucleotide reductase small subunit M2 promotes the proliferation of esophageal squamous cell carcinoma cells via HuR-mediated mRNA stabilization

Esophageal squamous cell carcinoma(ESCC),a malignancy of the digestive system,is highly prevalent and the primary cause of cancer-related deaths worldwide due to the lack of early diagnostic biomarkers and effective therapeutic targets.Dysregulated ribonucleotide reductase(RNR)expression has been confirmed to be causally linked to tumorigenesis.This study demonstrated that ribonucleotide reductase small subunit M2(RRM2)is significantly upregulated in ESCC tissue and that its expression is negatively correlated with clinical outcomes.Mechanistically,HuR promotes RRM2 mRNA stabilization by binding to the adenine/uridine(AU)-rich elements(AREs)within the 3′UTR,resulting in persistent overexpression of RRM2.Furthermore,bifonazole is identified as an inhibitor of HuR via computational screening and molecular docking analysis.Bifonazole disrupts HuR-ARE interactions by competitively binding to HuR at F65,R97,I103,and R153 residues,resulting in reduced RRM2 expression.Furthermore,bifonazole exhibited antitumor effects on ESCC patient-derived xenograft(PDX)models by decreasing RRM2 expression and the dNTP pool.In summary,this study reveals the interaction network among HuR,RRM2,and bifonazole and demonstrated that bifonazole is a potential therapeutic compound for ESCC through inhibition of the HuR/RRM2 axis.

Protein translation:biological processes and therapeutic strategies for human diseases

Protein translation is a tightly regulated cellular process that is essential for gene expression and protein synthesis.The deregulation of this process is increasingly recognized as a critical factor in the pathogenesis of various human diseases.In this review,we discuss how deregulated translation can lead to aberrant protein synthesis,altered cellular functions,and disease progression.We explore the key mechanisms contributing to the deregulation of protein translation,including functional alterations in translation factors,tRNA,mRNA,and ribosome function.Deregulated translation leads to abnormal protein expression,disrupted cellular signaling,and perturbed cellular functions-all of which contribute to disease pathogenesis.The development of ribosome profiling techniques along with mass spectrometry-based proteomics,mRNA sequencing and single-cell approaches have opened new avenues for detecting diseases related to translation errors.Importantly,we highlight recent advances in therapies targeting translation-related disorders and their potential applications in neurodegenerative diseases,cancer,infectious diseases,and cardiovascular diseases.Moreover,the growing interest lies in targeted therapies aimed at restoring precise control over translation in diseased cells is discussed.In conclusion,this comprehensive review underscores the critical role of protein translation in disease and its potential as a therapeutic target.Advancements in understanding the molecular mechanisms of protein translation deregulation,coupled with the development of targeted therapies,offer promising avenues for improving disease outcomes in various human diseases.Additionally,it will unlock doors to the possibility of precision medicine by offering personalized therapies and a deeper understanding of the molecular underpinnings of diseases in the future.

Cellular proteomic profiling of esophageal epithelial cells cultured under physioxia or normoxia reveals high correlation of radiation response

Objective To investigate the radiation response and proteomic profiling of esophageal epithelial cells cultured under physioxia and normoxia.Methods The human immortalized normal esophageal epithelial cell line SHEE cells were cultured under normoxia(21%)and physioxia(4%),respectively.A clonogenic assay was performed to evaluate the radiation response of SHEE cells.Cellular proteomic profiling of SHEE cells maintained under physioxia and normoxia was conducted to determine the differentially expressed proteins.Then,the identified differentially expressed proteins were validated by Western blot.Results SHEE cells exposed to normoxia showed an increased radiation response compared to physioxia(irradiation dose≥10Gy,P<0.05).Over 1200 non-redundant proteins were identified in the collected samples.Protein expression was compared between physioxia and normoxia,42 proteins were downregulated and 45 proteins upregulated,in which oxidative phosphorylation was the most significantly enriched pathway.When cells were cultured under normoxia conditions,the induction of antioxidant genes appeared to contribute to form a phenotype adapted to the environment with high oxygen-content.Further analysis validated NRF2,BIP,VCP,SOD1,and YAP1 were the key regulators of this phenotype.Conclusions Compared with physioxia,normoxic cell culture condition can enhance the radiation response.This study could stimulate in vivo microenvironment,and provide a basis for radiation-induced normal tissue damage.

Cdc2-like kinases:structure,biological function,and therapeutic targets for diseases

The CLKs(Cdc2-like kinases)belong to the dual-specificity protein kinase family and play crucial roles in regulating transcript splicing via the phosphorylation of SR proteins(SRSF1–12),catalyzing spliceosome molecular machinery,and modulating the activities or expression of non-splicing proteins.The dysregulation of these processes is linked with various diseases,including neurodegenerative diseases,Duchenne muscular dystrophy,inflammatory diseases,viral replication,and cancer.Thus,CLKs have been considered as potential therapeutic targets,and significant efforts have been exerted to discover potent CLKs inhibitors.In particular,clinical trials aiming to assess the activities of the small molecules Lorecivivint on knee Osteoarthritis patients,and Cirtuvivint and Silmitasertib in different advanced tumors have been investigated for therapeutic usage.In this review,we comprehensively documented the structure and biological functions of CLKs in various human diseases and summarized the significance of related inhibitors in therapeutics.Our discussion highlights the most recent CLKs research,paving the way for the clinical treatment of various human diseases.

Erianin suppresses constitutive activation of MAPK signaling pathway by inhibition of CRAF and MEK1/2

Constitutive activation of RAS-RAF-MEK-ERK signaling pathway(MAPK pathway)frequently occurs in many cancers harboring RAS or RAF oncogenic mutations.Because of the paradoxical activation induced by a single use of BRAF or MEK inhibitors,dual-target RAF and MEK treatment is thought to be a promising strategy.In this work,we evaluated erianin is a novel inhibitor of CRAF and MEK1/2 kinases,thus suppressing constitutive activation of the MAPK signaling pathway induced by BRAF V600E or RAS mutations.KinaseProfiler enzyme profiling,surface plasmon resonance(SPR),isothermal titration calorimetry(ITC),cellular thermal shift assay,computational docking,and molecular dynamics simulations were utilized to screen and identify erianin binding to CRAF and MEK1/2.Kinase assay,luminescent ADP detection assay,and enzyme kinetics assay were investigated to identify the efficiency of erianin in CRAF and MEK1/2 kinase activity.Notably,erianin suppressed BRAF V600E or RAS mutant melanoma and colorectal cancer cell by inhibiting MEK1/2 and CRAF but not BRAF kinase activity.Moreover,erianin attenuated melanoma and colorectal cancer in vivo.Overall,we provide a promising leading compound for BRAF V600E or RAS mutant melanoma and colorectal cancer through dual targeting of CRAF and MEK1/2.

Acetylshikonin inhibits inflammatory responses and Papain-like protease activity in murine model of COVID-19

Dear Editor,The emerging severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variant Omicron has rapidly replaced the Delta variant and presents a huge challenge to public health and health care infrastructure.Cytokine-driven hyperinflammation is the leading cause of a series of COVID-19 clinical symptoms.1 Our research attempted to discover an anti-inflammatory or anti-viral small molecule agent capable of treating COVID-19 hyperinflammation.

Repurposed benzydamine targeting CDK2 suppresses the growth of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the leading causes of cancer death worldwide. It is urgent to develop new drugs to improve the prognosis of ESCC patients. Here, we found benzydamine, a locally acting non-steroidal anti-inflammatory drug, had potent cytotoxic effect on ESCC cells. Benzydamine could suppress ESCC proliferation in vivo and in vitro. In terms of mechanism, CDK2 was identified as a target of benzydamine by molecular docking, pull-down assay and in vitro kinase assay. Specifically, benzydamine inhibited the growth of ESCC cells by inhibiting CDK2 activity and affecting downstream phosphorylation of MCM2, c-Myc and Rb, resulting in cell cycle arrest. Our study illustrates that benzydamine inhibits the growth of ESCC cells by downregulating the CDK2 pathway.

Two human monoclonal SARS-CoV-2 antibodies that maintain neutralizing potency against the SARS-CoV-2 Omicron BA.1 and BA.2 variants

The pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continues to sweep the globe with devastating consequences on human lives and world economy.As an RNA virus,SARS-CoV-2 has a relatively high mutation rate and is rapidly evolving.Thus,new SARS-CoV-2 variants continued to emerge,5 of which were designated by the World Health Organization(WHO)as variants of concern(VOCs),Alpha(B.1.1.7).

Dronedarone inhibits the proliferation of esophageal squamous cell carcinoma through the CDK4/CDK6-RB1 axis in vitro and in vivo

Treatment options for patients with esophageal squamous cell carcinoma(ESCC)often result in poor prognosis and declining health-related quality of life.Screening FDA-approved drugs for cancer chemoprevention is a promising and cost-efficient strategy.Here,we found that dronedarone,an antiarrhythmic drug,could inhibit the proliferation of ESCC cells.Moreover,we conducted phosphorylomics analysis to investigate the mechanism of dronedarone-treated ESCC cells.Through computational docking models and pull-down assays,we demonstrated that dronedarone could directly bind to CDK4 and CDK6 kinases.We also proved that dronedarone effectively inhibited ESCC proliferation by targeting CDK4/CDK6 and blocking the G0/G1 phase through RB1 phosphorylation inhibition by in vitro kinase assays and cell cycle assays.Subsequently,we found that knocking out CDK4 and CDK6 decreased the susceptibility of ESCC cells to dronedarone.Furthermore,dronedarone suppressed the growth of ESCC in patient-derived tumor xenograft models in vivo.Thus,our study demonstrated that dronedarone could be repurposed as a CDK4/6 inhibitor for ESCC chemoprevention.