Targeting the MAPK Pathway in KRAS-Driven Tumors

Formation and resuscitation of viable but non-culturable (VBNC) yeast in the food industry: A review

The viable but non-culturable (VBNC) state is a survival strategy adopted by microorganisms in response to unfavorable conditions in the environment. VBNC cells are unable to form colonies but still maintain a low level of activity, posing a potential threat to food safety and public health. Therefore, the development of effective strategies to prevent the formation and resuscitation of VBNC cells of microorganisms is a key challenge in food science and microbiology research. However, current research on VBNC cells has primarily focused on bacteria, with relatively limited reports on fungi. This paper provides a comprehensive and systematic review of yeast in the VBNC state, discussing various factors that induce and facilitate resuscitation, along with detection methods and formation and recovery mechanisms. A comprehensive understanding of the induction and resuscitation of yeast in the VBNC state and exploration of its molecular mechanism hold significant implications for food safety and public health. It is imperative to enhance our comprehension of the underlying mechanisms and contributory factors pertaining to VBNC yeast, thereby facilitating the efficient management of the food fermentation process and ensuring the integrity of food quality and safety.

A phase Ib study of the combination of naporafenib with rineterkib or trametinib in patients with advanced and metastatic KRAS- or BRAF-mutant non-small cell lung cancer

BACKGROUND

Genetic alterations activating the MAPK pathway are common in non-small cell lung cancer (NSCLC). Patients with NSCLC may benefit from treatment with the pan-RAF inhibitor naporafenib (LXH254) plus the ERK1/2 inhibitor rineterkib (LTT462) or MEK1/2 inhibitor trametinib.

METHODS

This first-in-human phase 1b dose-escalation/dose-expansion study investigated the combinations of naporafenib (50-350 mg once daily [QD] or 300-600 mg twice daily [BID]) with rineterkib (100-300 mg QD) in patients with KRAS-/BRAF-mutant NSCLC and naporafenib (200 mg BID or 400 mg BID) with trametinib (0.5 mg QD, 1 mg QD or 1 mg QD 2 weeks on/2 weeks off) in patients with KRAS-/BRAF-mutant NSCLC and NRAS-mutant melanoma. The primary objectives were to identify the recommended dose for expansion (RDE) and evaluate tolerability and safety. Secondary objectives included antitumor activity and pharmacodynamics.

RESULTS

Overall, 216 patients were treated with naporafenib plus rineterkib (NSCLC: n = 101) or naporafenib plus trametinib (NSCLC: n = 79; melanoma: n = 36). In total, 10 of 62 (16%) patients experienced at least one dose-limiting toxicity. The RDEs were established as naporafenib 400 mg BID plus rineterkib 200 mg QD, naporafenib 200 mg BID plus trametinib 1 mg QD and naporafenib 400 mg BID plus trametinib 0.5 mg QD. The most frequent grade ≥ 3 treatment-related adverse event was increased lipase (8/101 [7.9%] patients) for naporafenib plus rineterkib and rash (22/115 [19.1%] patients) for naporafenib plus trametinib. Among patients with NSCLC, partial response was observed in three patients (one with KRAS-mutant, two with BRAFnon-V600-mutant NSCLC) treated with naporafenib plus rineterkib and two patients (both with KRAS-mutant NSCLC) treated with naporafenib plus trametinib. On-treatment median reductions in DUSP6 mRNA levels from baseline were 45.5% and 76.1% with naporafenib plus rineterkib or trametinib, respectively.

CONCLUSIONS

Both naporafenib combinations had acceptable safety profiles. Antitumor activity was limited in patients with NSCLC, despite the observed on-target pharmacodynamic effect.

CLINICALTRIALS

gov identifier: NCT02974725.

DEPDC1 affects autophagy-dependent glycolysis levels in human osteosarcoma cells by modulating RAS/ERK signaling through TTK

The current treatment for osteosarcoma (OS) is based on surgery combined with systemic chemotherapy, however, gene therapy has been hypothesized to improve patient survival rates. The density-enhanced protein domain 1 protein (DEPDC1) functions as a crucial determinant in the advancement of OS, which is highly expressed in OS cells. The current study was designed to delve into the effect and mechanism of DEPDC1 and phosphotyrosine-picked threonine tyrosine kinase (TTK) in OS. The expression of DEPDC1 and TTK in OS cells was detected by western blotting. Furthermore, the assessment of glycolysis encompassed the quantification of extracellular acidification rate, glucose uptake rate, lactate concentration, and the expression of glucose transporter 1, hexokinase 2, and pyruvate kinase M2. Finally, the functions of DEPDC1 and TTK in autophagy and ras-extracellular signal-regulated kinase signaling were determined by western blotting after interfering with DEPDC1 in SaOS-2 cells. The results revealed that DEPDC1 and TTK were upregulated in OS cell lines and interfering with DEPDC1 inhibited glycolysis and autophagy in OS cells. Furthermore, the STRING database suggested that DEPDC1 and TTK perform targeted binding. Notably, the results of the present study revealed that DEPDC1 upregulated RAS expression through TTK and enhanced ERK activity, thereby affecting glycolysis and autophagy in OS cells. Collectively, the present investigation demonstrated that DEPDC1 affected autophagy-dependent glycolysis levels of OS cells by regulating RAS/ERK signaling through TTK.

Hsa_circ_0010023 promotes the development of papillary thyroid carcinoma by sponging miR-1250-5p

BACKGROUND

Papillary thyroid cancer (PTC) is the most common thyroid tumor (TC). However, there is still a lack of effective indicators for PTC detection and prognosis. We intended to find a novel tumor marker for the progression of PTC.

METHODS

The expression of circRNAs was measured by quantitative real-time polymerase chain reaction (qRT-PCR). SiRNA transfection was used to knockdown the expression of hsa_circ_0010023 in K1 cells. Cell proliferation was evaluated using cell counting and CCK8. Cell apoptosis was analyzed using flow cytometry. Hsa_circ_0010023 downstream pathways were predicted with bio-informatics analysis. The miR-1250-5p and MAPK1 were measured by qRT-PCR. The interaction between miR-1250-5p and hsa_circ_0010023 was vertified by dual-luciferase reporter assay.

RESULTS

Among the four circRNAs screened, only hsa_circ_0010023 and hsa_circ_0128482 were highly expressed in PTC (P < 0.05). The expression of hsa_circ_0010023 was significantly correlated with lymph node metastasis and extrathyroid infiltration (P < 0.05). Compared with the control group, the cell proliferation of the si-circ-0010023 group was significantly inhibited (P < 0.05). Knockdown of hsa_circ_0010023 promotes apoptosis of K1 cells (P < 0.001). The expression of hsa_circ_0010023 was negatively correlated with miR-1250-5p and positively correlated with MAPK1. MiR-1250-5p overexpression significantly reduced the luciferase activity of wild type plasmid (hsa_circ_0010023 WT), but not that of mutant type plasmid (hsa_circ_0010023 MUT).

CONCLUSION

The expression level of hsa_circ_0010023 was positive related to the progression of PTC, and hsa_circ_0010023 may promote PTC through sponging miR-1250-5p. Hsa_circ_0010023 may be a potential bio-marker for the diagnosis of PTC.

MAPK signaling pathway induced LOX-1+ polymorphonuclear myeloid-derived suppressor cells in biliary atresia

Biliary atresia (BA) is a severe pediatric liver disease characterized by progressive bile duct destruction and fibrosis, leading to significant liver damage and frequently necessitating liver transplantation. This study elucidates the role of LOX-1+ polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in BA pathogenesis and assesses their potential as non-invasive early diagnostic biomarkers. Using flow cytometry, immunofluorescence, and molecular profiling, we analyzed the expression and activity of these cells in peripheral blood and liver tissues from BA patients and controls. Our findings reveal a significant increase in the frequencies and function of LOX-1+PMN-MDSCs in BA patients, along with MAPK signaling pathway upregulation, indicating their involvement in disease mechanisms. Additionally, the frequencies of LOX-1+PMN-MDSC in peripheral blood significantly positively correlate with liver function parameters in BA patients, demonstrating diagnostic performance comparable to traditional serum markers. These findings suggest that LOX-1+PMN-MDSCs contribute to the immunosuppressive environment in BA and could serve as potential diagnostic targets.

TRIM21 induces selective autophagic degradation of c-Myc and sensitizes regorafenib therapy in colorectal cancer

Kirsten rat sarcoma virus (KRAS) mutation is associated with malignant tumor transformation and drug resistance. However, the development of clinically effective targeted therapies for KRAS-mutant cancer has proven to be a formidable challenge. Here, we report that tripartite motif-containing protein 21 (TRIM21) functions as a target of extracellular signal-regulated kinase 2 (ERK2) in KRAS-mutant colorectal cancer (CRC), contributing to regorafenib therapy resistance. Mechanistically, TRIM21 directly interacts with and ubiquitinates v-myc avian myelocytomatosis viral oncogene homolog (c-Myc) at lysine 148 (K148) via K63-linkage, enabling c-Myc to be targeted to the autophagy machinery for degradation, ultimately resulting in the downregulation of enolase 2 expression and inhibition of glycolysis. However, mutant KRAS (KRAS/MT)-driven mitogen-activated protein kinase (MAPK) signaling leads to the phosphorylation of TRIM21 (p-TRIM21) at Threonine 396 (T396) by ERK2, disrupting the interaction between TRIM21 and c-Myc and thereby preventing c-Myc from targeting autophagy for degradation. This enhances glycolysis and contributes to regorafenib resistance. Clinically, high p-TRIM21 (T396) is associated with an unfavorable prognosis. Targeting TRIM21 to disrupt KRAS/MT-driven phosphorylation using the antidepressant vilazodone shows potential for enhancing the efficacy of regorafenib in treating KRAS-mutant CRC in preclinical models. These findings are instrumental for KRAS-mutant CRC treatment aiming at activating TRIM21-mediated selective autophagic degradation of c-Myc.

Comprehensive analysis of MAPK genes in the prognosis, immune characteristics, and drug treatment of renal clear cell carcinoma using bioinformatic analysis and Mendelian randomization

Mitogen-activated protein kinase (MAPK) signalling is vitally important in tumour development and progression. This study is the first to comprehensively analyse the role of MAPK-family genes in the progression, prognosis, immune-cell infiltration, methylation, and potential therapeutic value drug candidates in ccRCC. We identified a novel prognostic panel of six MAPK-signature genes (MAP3K12, MAP3K1, MAP3K5, MAPK1, MAPK8, MAPK9), and introduced a robust MAPK-signature risk model for predicting ccRCC prognosis. Model construction, evaluation, and external validation using datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database demonstrated its stability, as well as high sensitivity and specificity. Enrichment analysis suggested the participation of immune-mediated mechanism in MAPK dysregulation in ccRCC. Immune-infiltration analysis confirmed the relationship and revealed that the MAPK-signature risk model might stratify immunotherapy response in ccRCC, which was verified in drug sensitivity analysis and validated in external ccRCC immunotherapy dataset (GSE67501). Potential therapeutic drug predictions for key MAPKs using DSigDB, Network Analyst, CTD, and DGIdb were subsequently verified by molecular docking with AutoDock Vina and PyMol. Mendelian randomization further demonstrated the possibilities of the MAPK-signature genes as targets for therapeutic drugs in ccRCC. Methylation analysis using UALCAN and MethSurv revealed the participation of epigenetic modifications in dysregulation and survival difference of MAPK pathway in ccRCC. Among the key MAPKs, MAP3K12 exhibited the highest significance, indicating its independent prognostic value as single gene in ccRCC. Knockout and overexpression validation experiments in vitro and in vivo found that MAP3K12 acted as a promoter of tumour progression in RCC, suggesting a pivotal role for MAP3K12 in the proliferation, migration, and invasion of RCC cells. Our findings proposed the potential of MAPK-signature genes as biomarkers for prognosis and therapy response, as well as targets for therapeutic drugs in ccRCC.

MAPK Signaling-Mediated RFNG Phosphorylation and Nuclear Translocation Restrain Oxaliplatin-Induced Apoptosis and Ferroptosis

Chemotherapy resistance remains a major challenge in the treatment of colorectal cancer (CRC). Therefore, it is crucial to develop novel strategies to sensitize cancer cells to chemotherapy. Here, the fringe family is screened to determine their contribution to chemotherapy resistance in CRC. It is found that RFNG depletion significantly sensitizes cancer cells to oxaliplatin treatment. Mechanistically, chemotherapy-activated MAPK signaling induces ERK to phosphorylate RFNG Ser255 residue. Phosphorylated RFNG S255 (pS255) interacts with the nuclear importin proteins KPNA1/importin-α1 and KPNB1/importin-β1, leading to its translocation into the nucleus where it targets p53 and inhibits its phosphorylation by competitively inhibiting the binding of CHK2 to p53. Consequently, the expression of CDKN1A is decreased and that of SLC7A11 is increased, leading to the inhibition of apoptosis and ferroptosis. In contrast, phosphor-deficient RFNG S225A mutant showed increased apoptosis and ferroptosis, and exhibited a notable response to oxaliplatin chemotherapy both in vitro and in vivo. It is further revealed that patients with low RFNG pS255 exhibited significant sensitivity to oxaliplatin in a patient-derived xenograft (PDX) model. These findings highlight the crosstalk between the MAPK and p53 signaling pathways through RFNG, which mediates oxaliplatin resistance in CRC. Additionally, this study provides guidance for oxaliplatin treatment of CRC patients.

IL1RL2 is related to the expression and prognosis of bladder cancer

IL1RL2 has been reported to be highly expressed in a variety of tumor types whereas its role in bladder cancer (BLCA) remains unclear. The aim of the present study was to explore the prognostic value of Il1RL2 in BLCA and its relationship with clinical pathological features. The Cancer Genome Atlas (TCGA) database was used to assess the levels of IL1RL2 expression in BLCA tissues and cells, which were validated by reverse transcription-quantitative polymerase chain reaction and western blotting. Immunohistochemistry was employed to analyze expression of the IL1RL2 gene in 17 pairs of tumor and normal specimens, as well as 112 samples with different stages and grades of tumors. To investigate the biological functions of Il1RL2 in BLCA, co-expression networks and functional enrichment analyses were conducted. A protein-protein interaction network was constructed using interaction gene search tools. IL1RL2 was revealed to be clearly expressed in BLCA cells and tissues. The area under the curve for amplification of IL1RL2 distinguishing between tumor and normal tissues was 0.700 (95% CI: 0.579-0.821) in the TCGA database and 0.647 (95% CI: 0.497-0.797) in Miyun chart database, respectively. Furthermore, in our database, both univariate and multivariate analyses indicated that IL1RL2 expression was an independent risk factor for overall survival (OS). Kaplan-Meier survival analysis revealed an association between high IL1RL2 expression and low OS. Pathway enrichment analysis suggested that IL1RL2 is involved in the regulation of tumor progression through the MAPK signaling pathway. The expression level of IL1RL2 was associated with the stage, grade, lymph node album and prognosis of BLCA.

The molecular mechanism underlying KRAS regulation on STK31 expression in pancreatic ductal adenocarcinoma

KRAS gene mutations are common in pancreatic ductal adenocarcinoma (PDAC), but targeting mutant KRAS is still challenging. Here, an endoribonuclease-prepared small interfering RNA (esiRNA) library was used to screen new kinases that play critical roles in PDAC driven by KRAS gene mutations, and serine/threonine kinase 31 (STK31) was identified and characterized as a potential therapeutic target for KRAS-mutant PDAC. Our results showed that STK31 was upregulated in KRAS-mutant PDAC patients with poor survival and highly expressed in PDAC cell lines with KRASG12D mutation. Inhibition of STK31 in KRAS-mutant cell lines significantly reduced PDAC cell growth in vitro and hindered tumor growth in vivo. Gain and loss of function experiments revealed that STK31 is a downstream target of KRAS in PDAC. A pharmacological inhibition assay showed MAPK/ERK signaling involved in STK31 regulation. The further mechanistic study validated that c-Jun, regulated by KRAS/MAPK signaling, directly modulates the transcription level of STK31 by binding to its promoter region. Through RNA sequencing, we found that the cell cycle regulators CCNB1 and CDC25C are downstream targets of STK31. Taken together, our results indicate that STK31, which is the downstream target of the KRAS/MAPK/ERK/c-Jun signaling pathway in KRAS-mutant PDAC, promotes PDAC cell growth by modulating the expression of the cell cycle regulators CCNB1 and CDC25C.

Extra-temporal pediatric low-grade gliomas and epilepsy

Low-grade gliomas, especially glioneuronal tumors, are a common cause of epilepsy in children. Seizures associated with low-grade pediatric tumors are medically refractory and present a significant burden to patients. Often, morbidity and patients´ quality of life are determined rather by the control of seizures than the oncological process itself and the resolution of epilepsy represents an important part in the treatment of LGGs. The pathogenesis of tumor-related seizures in focal LGG tumors is multifactorial, and mechanisms differ probably among patients and tumor types. Pediatric low-grade tumors associated with epilepsy include a series of neoplasms that have a pure astrocytic or glioneuronal lineage. They are usually benign tumors with a neocortical localization typically in the temporal lobes, but also in other supratentorial locations. Gangliogliomas and dysembryoplastic neuroepithelial tumors (DNET) are the most common entities together with astrocytic gliomas (pilocytic astrocytomas and pleomorphic xanthoastrocytoma) and angiocentric gliomas, and dual pathology is found in up to 40% of glioneuronal tumors. The treatment of low-grade gliomas and associated epilepsy is based mainly on resection and the extent of surgery is the main predictor of postoperative seizure control in patients with a LGG. Long-term epilepsy-associated tumors (LEATs) tend to be well-circumscribed, and therefore, the chances for a complete resection and epilepsy control with a safe approach are very high. New treatments have emerged as alternatives to open microsurgical approaches, including laser thermal ablation or the use of BRAF inhibitors. Future advances in identifying seizure-related biomarkers and molecular tumor pathways will facilitate targeted treatment strategies that will have a deep impact both in oncologic and epilepsy outcomes.

Mediating kinase activity in Ras-mutant cancer: potential for an individualised approach?

It is widely acknowledged that there is a considerable number of oncogenic mutations within the Ras superfamily of small GTPases which are the driving force behind a multitude of cancers. Ras proteins mediate a plethora of kinase pathways, including the MAPK, PI3K, and Ral pathways. Since Ras was considered undruggable until recently, pharmacological targeting of pathways downstream of Ras has been attempted to varying success, though drug resistance has often proven an issue. Nuances between kinase pathway activation in the presence of various Ras mutants are thought to contribute to the resistance, however, the reasoning behind activation of different pathways in different Ras mutational contexts is yet to be fully elucidated. Indeed, such disparities often depend on cancer type and disease progression. However, we are in a revolutionary age of Ras mutant targeted therapy, with direct-targeting KRAS-G12C inhibitors revolutionising the field and achieving FDA-approval in recent years. However, these are only beneficial in a subset of patients. Approximately 90% of Ras-mutant cancers are not KRAS-G12C mutant, and therefore raises the question as to whether other distinct amino acid substitutions within Ras may one day be targetable in a similar manner, and indeed whether better understanding of the downstream pathways these various mutants activate could further improve therapy. Here, we discuss the favouring of kinase pathways across an array of Ras-mutant oncogenic contexts and assess recent advances in pharmacological targeting of various Ras mutants. Ultimately, we will examine the utility of individualised pharmacological approaches to Ras-mediated cancer.

Targeting the RAS upstream and downstream signaling pathway for cancer treatment

Cancer often involves the overactivation of RAS/RAF/MEK/ERK (MAPK) and PI3K-Akt-mTOR pathways due to mutations in genes like RAS, RAF, PTEN, and PIK3CA. Various strategies are employed to address the overactivation of these pathways, among which targeted therapy emerges as a promising approach. Directly targeting specific proteins, leads to encouraging results in cancer treatment. For instance, RTK inhibitors such as imatinib and afatinib selectively target these receptors, hindering ligand binding and reducing signaling initiation. These inhibitors have shown potent efficacy against Non-Small Cell Lung Cancer. Other inhibitors, like lonafarnib targeting Farnesyltransferase and GGTI 2418 targeting geranylgeranyl Transferase, disrupt post-translational modifications of proteins. Additionally, inhibition of proteins like SOS, SH2 domain, and Ras demonstrate promising anti-tumor activity both in vivo and in vitro. Targeting downstream components with RAF inhibitors such as vemurafenib, dabrafenib, and sorafenib, along with MEK inhibitors like trametinib and binimetinib, has shown promising outcomes in treating cancers with BRAF-V600E mutations, including myeloma, colorectal, and thyroid cancers. Furthermore, inhibitors of PI3K (e.g., apitolisib, copanlisib), AKT (e.g., ipatasertib, perifosine), and mTOR (e.g., sirolimus, temsirolimus) exhibit promising efficacy against various cancers such as Invasive Breast Cancer, Lymphoma, Neoplasms, and Hematological malignancies. This review offers an overview of small molecule inhibitors targeting specific proteins within the RAS upstream and downstream signaling pathways in cancer.

Synergistic anti-tumor activity, reduced pERK, and immuno-stimulatory cytokine profiles with 5-FU or ONC212 plus KRAS G12D inhibitor MRTX1133 in CRC and pancreatic cancer cells independent of G12D mutation

KRAS mutations occur in ~40-50% of mCRC and are associated with aggressive disease that is refractory to anti-EGFR therapies. Pancreatic cancer harbors ~90% KRAS driver gene mutation frequency. Small molecules targeting KRAS G12C gained FDA approval for KRAS G12C-mutated NSCLC. ONC212, a fluorinated imipridone with nM anti-cancer activity has preclinical efficacy against pancreatic cancer and other malignancies. MRTX1133, identified as a noncovalent selective KRAS G12D inhibitor that suppresses G12D signaling by binding to the switch II pocket thereby inhibiting protein-protein interactions. We investigated cell viability, drug synergies, pERK suppression and cytokine, chemokine or growth factor alterations following treatment with 5-Fluorouracil (5-FU) or ONC212 plus MRTX1133 in 6 human CRC and 4 human pancreatic cancer cell lines. IC50 sensitivities ranged from 7 to 12 µM for 5-FU, 0.2-0.8 µM for ONC212, and > 100 nM to > 5,000 nM for MRTX1133 (G12D N = 4: LS513 > 100, HPAF-II > 1,000, SNUC2B > 5,000, PANC-1 > 5,000). For non-G12D, the range of IC50 for MRTX1133 was > 1,000 to > 5,000 nM for CRC lines with G12V, G13D, or WT KRAS (N = 7). Synergies between MRTX1133 plus 5-FU or ONC212 were observed regardless of KRAS G12D mutation with combination indices of < 0.5 indicating strong synergy. Observed synergies were greater with MRTX1133 plus ONC212 compared to MRTX1133 plus 5-FU. pERK was suppressed with mutant but not wild-type KRAS at nM MRTX1133 doses. Immunostimulatory profiles included reduction in IL8/CXCL8, MICA, Angiopoietin 2, VEGF and TNF-alpha and increase in IL-18/IL-1F4 with MRTX treatments and combinations. Our studies reveal preclinical activity of MRTX1133 alone or synergies when combined with 5-FU or ONC212 against mCRC and pancreatic cancer cells regardless of KRAS G12D mutation. The results suggest that KRAS G12V and KRAS G13D should be further considered in clinical trials including combination therapies involving MRTX1133 and 5-FU or ONC212.

SHANK3 depletion leads to ERK signalling overdose and cell death in KRAS-mutant cancers

The KRAS oncogene drives many common and highly fatal malignancies. These include pancreatic, lung, and colorectal cancer, where various activating KRAS mutations have made the development of KRAS inhibitors difficult. Here we identify the scaffold protein SH3 and multiple ankyrin repeat domain 3 (SHANK3) as a RAS interactor that binds active KRAS, including mutant forms, competes with RAF and limits oncogenic KRAS downstream signalling, maintaining mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) activity at an optimal level. SHANK3 depletion breaches this threshold, triggering MAPK/ERK signalling hyperactivation and MAPK/ERK-dependent cell death in KRAS-mutant cancers. Targeting this vulnerability through RNA interference or nanobody-mediated disruption of the SHANK3-KRAS interaction constrains tumour growth in vivo in female mice. Thus, inhibition of SHANK3-KRAS interaction represents an alternative strategy for selective killing of KRAS-mutant cancer cells through excessive signalling.

SPRED3 regulates the NF-κB signaling pathway in thyroid cancer and promotes the proliferation

SPRED3 (Sprouty-related EVH1 domain containing 3) mutants are depicted in various cancers, however, nothing is known about its biofunction in thyroid cancer (THCA). Bioinformatic analyses were conducted to ascertain the level of SPRED3 expression in THCA tissues and its importance in the prognosis of THCA patients. Flag-SPRED3 plasmid and SPRED3-knockout vector were developed to overexpress or deplete the SPRED3 expression in THCA cells. The function of SPRED3 on THCA cell proliferation was examined using the colony formation assay and CCK8 assay. The effect of SPRED3 expression on the transcriptional activity of NF-κB was also examined using luciferase reporter assays. High SPRED3 expression was associated with unfavorable clinical outcomes, advanced tumor characteristics, and traditional molecular markers of papillary thyroid cancer in THCA patients. Genetic analysis revealed differences in mutation rates in key genes between SPRED3-high and SPRED3-low THCA cases. It is also revealed that SPRED3 influenced the immune microenvironment, with increased stromal and immune scores and altered immune cell infiltration. Functionally, SPRED3 overexpression enhanced THCA cell viability and colony formation, while its depletion reduced cell growth and proliferation. In vivo experiments in mice confirmed the inhibitory effect of SPRED3 depletion on tumor growth. Mechanically, we found that SPRED3 activated the NF-κB signaling. For the first time, we found that SPRED3 promotes THCA cell proliferation via the NF-κB signaling pathway. This finding may provide insight into SPRED3's prognostic potential in thyroid cancer and provide the rationale for SPRED3-targeted druggable interventions.

CircRAPGEF5 acts as a modulator of RAS/RAF/MEK/ERK signaling during colorectal carcinogenesis

Mutations in oncogenes such as KRAS, NRAS and BRAF promote the growth and survival of tumors, while excessive RAS/RAF/MEK/ERK activation inhibits tumor growth. In this study we examined the precise regulatory machinery that maintains a moderate RAS/RAF/MEK/ERK pathway activation during CRC. Here, using bioinformatic analysis, transcriptomic profiling, gene silencing and cellular assays we discovered that a circular RNA, circRAPGEF5, is significantly upregulated in KRAS mutant colorectal cancer (CRC) cells. CircRAPGEF5 suppressed mutant and constitutively activated KRAS and the expression of the death receptor TNFRSF10A. Silencing of circRAPGEF5-induced RAS/RAF/MEK/ERK signaling hyperactivation and apoptosis in CRC cells suggesting that an upregulation of circRAPEF5 may suppress the expression of TNFRSF10A and aid CRC progression by preventing apoptosis, while the direct interactions between circRAPGEF5 and elements of the RAS/RAF/MEK/ERK pathway was not identified, which nevertheless can be the basis for future research. Moreover, EIF4A3, was observed to share a similar expression pattern with circRAPEF5 and demonstrated to be a major controller of circRAPGEF5 via the promotion of circRAPGEF5 circularization and its silencing reduced circRAPGEF5 levels. Taken together, our findings reveal a mechanism of accurate RAS/RAF/MEK/ERK signaling regulation during CRC progression maintained by upregulation of circRAPGEF5 which may be a plausible target for future clinical applications that seek to induce CRC cell apoptosis via the RAS/RAF/MEK/ERK signaling pathway.

PDP1 promotes KRAS mutant colorectal cancer progression by serving as a scaffold for BRAF and MEK1

The oncogenic role of KRAS in colorectal cancer (CRC) progression is well-established. Despite this, identifying effective therapeutic targets for KRAS-mutated CRC remains a significant challenge. This study identifies pyruvate dehydrogenase phosphatase catalytic subunit 1 (PDP1) as a previously unrecognized yet crucial regulator in the progression of KRAS mutant CRC. A substantial upregulation of PDP1 expression is observed in KRAS mutant CRC cells and tissues compared to wild-type KRAS samples, which correlates with poorer prognosis. Functional experiments elucidate that PDP1 accelerates the malignance of KRAS mutant CRC cells, both in vitro and in vivo. Mechanistically, PDP1 acts as a scaffold, enhancing BRAF and MEK1 interaction and activating the MAPK signaling, thereby promoting CRC progression. Additionally, transcription factor KLF5 is identified as the key regulator for PDP1 upregulation in KRAS mutant CRC. Crucially, targeting PDP1 combined with MAPK inhibitors exhibits an obvious inhibitory effect on KRAS mutant CRC. Overall, PDP1 is underscored as a vital oncogenic driver and promising therapeutic target for KRAS mutant CRC.

The cytoglobin-dependent transcriptome in melanoma indicates a protective function associated with oxidative stress, inflammation and cancer-associated pathways

Cytoglobin (CYGB) is a member of the oxygen-binding globin superfamily. In this study we generated stable CYGB overexpressing A375 melanoma cells and performed RNA-sequencing to comprehensively explore the CYGB-dependent transcriptome. Our findings reveal that ectopic expression of CYGB dysregulated multiple cancer-associated genes, including the mTORC1 and AKT/mTOR signaling pathways, which are frequently overactivated in tumors. Moreover, several cancer-associated pathways, such as epithelial-mesenchymal transition (EMT) mediated by CSPG4, were downregulated upon CYGB overexpression. Intriguingly, ectopic expression suggested anti-inflammatory potential of CYGB, as exemplified by downregulation of key inflammasome-associated genes, including NLRP1, CASP1 and CD74, which play pivotal roles in cytokine regulation and inflammasome activation. Consistent with established globin functions, CYGB appears to be involved in redox homeostasis. Furthermore, our study indicates CYGB's association to DNA repair mechanisms and its regulation of NOX4, reinforcing its functional versatility. Additionally, multiple significantly enriched pathways in CYGB overexpressing cells were consistently dysregulated in opposite direction in CYGB depleted cells. Collectively, our RNA-sequencing based investigations illustrate the diverse functions of CYGB in melanoma cells, pointing to its putative roles in cellular protection against oxidative stress, inflammation, and cancer-associated pathways. These findings pave the way for further research into the physiological role of CYGB and its potential as a candidate therapeutic target in melanoma.

Identification of ENTPD1 as a novel biomarker linking allergic rhinitis and systemic lupus erythematosus

Several studies reveal that allergic rhinitis (AR) is a significant risk factor of systemic lupus erythematosus (SLE). However, studies investigating the common pathogenesis linking AR and SLE are lacking. Our study aims to search for the shared biomarkers and mechanisms that may provide new therapeutic targets for preventing AR from developing SLE. GSE50223 for AR and GSE103760 for SLE were downloaded from the Gene Expression Omnibus (GEO) database to screen differentially expressed genes (DEGs). The Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed to explore the functions of shared DEGs. Hub genes were screened by cytoHubba (a plugin of Cytoscape) and validated in another two datasets. Gene set enrichment analysis (GSEA) and single-sample Gene set enrichment analysis (ssGSEA) algorithm were applied to understand the functions of hub gene. ENTPD1 was validated as a hub gene between AR and SLE. GSEA results revealed that ENTPD1 was associated with KRAS_SIGNALING_UP pathway in AR and related to HYPOXIA, TGF_BETA_SIGNALING and TNFA_SIGNALING_VIA_NFKB pathways in SLE. The expression of ENTPD1 was positively correlated with activated CD8 T cell in both diseases. Thus, ENTPD1 may be a novel therapeutic target for preventing AR from developing SLE.

Rupatadine-inhibited OTUD3 promotes DLBCL progression and immune evasion through deubiquitinating MYL12A and PD-L1

The obstacle to effectively treating Diffuse Large B-cell Lymphoma (DLBCL) lies in the resistance observed toward standard therapies. Identifying therapeutic targets that prove effective for relapsed or refractory patients poses a significant challenge. OTUD3, a deubiquitinase enzyme, is overexpressed in DLBCL tissues. However, its role in DLBCL has not been investigated. Our study has brought to light the multifaceted impact of OTUD3 in DLBCL. Not only does it enhance cell survival through the deubiquitination of MYL12A, but it also induces CD8+ T cell exhaustion within the local environment by deubiquitinating PD-L1. Our findings indicate that the OTUD3 inhibitor, Rupatadine, exerts its influence through competitive binding with OTUD3. This operation diminishes the deubiquitination of both MYL12A and PD-L1 by OTUD3. This research unveils the central and oncogenic role of OTUD3 in DLBCL and highlights the potential clinical application value of the OTUD3 inhibitor, Rupatadine. These findings contribute valuable insights into addressing the challenges of resistant DLBCL cases and offer a promising avenue for further clinical exploration.

Knockdown of miR-1293 attenuates lung adenocarcinoma angiogenesis via Spry4 upregulation-mediated ERK1/2 signaling inhibition

Lung adenocarcinoma (LUAD) is the most common histologic subtype of lung cancer. Angiogenesis plays a pivotal role in LUAD progression via supplying oxygen and nutrients for cancer cells. Non-coding miR-1293, a significantly up-regulated miRNA in LUAD tissues, can be potentially used as a novel biomarker for predicting the prognosis of LUAD patients. However, little information is available about the function of miR-1293 in LUAD progression especially cancer-induced angiogenesis. Herein, we found that miR-1293 knockdown could obviously attenuate LUAD-induced angiogenesis in vitro and down-regulate two most important pro-angiogenic cytokines VEGF-A and bFGF expression and secretion. Indeed, miR-1293 abrogation inactivated the angiogenesis-promoting ERK1/2 signaling characterized by decreased ERK1/2 phosphorylation and translocation from nucleus to cytoplasm. Next we found that miR-1293 knockdown reactivated the endogenous ERK1/2 pathway inhibitor Spry4 expression and Spry4 perturbance with specific siRNA transfection abolished the inhibition of ERK1/2 pathway and LUAD-induced angiogenesis by miR-1293 knockdown. Finally, with in vivo assay, we found obvious Spry4 up-regulation and VEGF-A, bFGF, ERK1/2 phosphorylation, micro-vessel density marker CD31 expression down-regulation in vivo, respectively. Collectively, these results indicated that miR-1293 knockdown could significantly attenuate LUAD angiogenesis via Spry4-mediated ERK1/2 signaling inhibition, which might be helpful for uncovering more functions of miR-1293 in LUAD and providing experimental basis for possible LUAD therapeutic strategy targeting miR-1293.

Inhibition of GTPase KRASG12D: a review of patent literature

INTRODUCTION

KRAS is a critical oncogenic protein intricately involved in tumor progression, and the difficulty in targeting KRAS has led it to be classified as an 'undruggable target.' Among the various KRAS mutations, KRASG12D is highly prevalent and represents a promising therapeutic target, yet there are currently no approved inhibitors for it.

AREA COVERED

This review summarizes numerous patents and literature featuring inhibitors or degraders of KRASG12D through searching relevant information in PubMed, SciFinder and Web of Science databases from 2021 to February 2024, providing an overview of the research progress on inhibiting KRASG12D in terms of design strategies, chemical structures, biological activities, and clinical advancements.

EXPERT OPINION

Since the approval of AMG510 (Sotorasib), there has been an increasing focus on the inhibition of KRASG12D, leading to numerous reports of related inhibitors and degraders. Among them, MRTX1133, as the first KRASG12D inhibitor to enter clinical trials, has demonstrated excellent tumor suppression in various KRASG12D-bearing human tumor xenograft models. It is important to note, however, that understanding the mechanisms of acquired resistance caused by KRAS inhibition and developing additional combination therapies is crucial. Moreover, seeking covalent inhibition of KRASG12D also holds significant potential.

Systematic loss-of-function screens identify pathway-specific functional circular RNAs

Circular RNA (circRNA) is covalently closed, single-stranded RNA produced by back-splicing. A few circRNAs have been implicated as functional; however, we lack understanding of pathways that are regulated by circRNAs. Here we generated a pooled short-hairpin RNA library targeting the back-splice junction of 3,354 human circRNAs that are expressed at different levels (ranging from low to high) in humans. We used this library for loss-of-function proliferation screens in a panel of 18 cancer cell lines from four tissue types harbouring mutations leading to constitutive activity of defined pathways. Both context-specific and non-specific circRNAs were identified. Some circRNAs were found to directly regulate their precursor, whereas some have a function unrelated to their precursor. We validated these observations with a secondary screen and uncovered a role for circRERE(4-10) and circHUWE1(22,23), two cell-essential circRNAs, circSMAD2(2-6), a WNT pathway regulator, and circMTO1(2,RI,3), a regulator of MAPK signalling. Our work sheds light on pathways regulated by circRNAs and provides a catalogue of circRNAs with a measurable function.

Magnesium Ions Promote the Induction of Immunosuppressive Bone Microenvironment and Bone Repair through HIF-1α-TGF-β Axis in Dendritic Cells

The effect of immunoinflammation on bone repair during the recovery process of bone defects needs to be further explored. It is reported that Mg2+ can promote bone repair with immunoregulatory effect, but the underlying mechanism on adaptive immunity is still unclear. Here, by using chitosan and hyaluronic acid-coated Mg2+ (CSHA-Mg) in bone-deficient mice, it is shown that Mg2+ can inhibit the activation of CD4+ T cells and increase regulatory T cell formation by inducing immunosuppressive dendritic cells (imDCs). Mechanistically, Mg2+ initiates the activation of the MAPK signaling pathway through TRPM7 channels on DCs. This process subsequently induces the downstream HIF-1α expression, a transcription factor that amplifies TGF-β production and inhibits the effective T cell function. In vivo, knock-out of HIF-1α in DCs or using a HIF-1α inhibitor PX-478 reverses inhibition of bone inflammation and repair promotion upon Mg2+-treatment. Moreover, roxadustat, which stabilizes HIF-1α protein expression, can significantly promote immunosuppression and bone repair in synergism with CSHA-Mg. Thus, the findings identify a key mechanism for DCs and its HIF-1α-TGF-β axis in the induction of immunosuppressive bone microenvironment, providing potential targets for bone regeneration.

The serine protease CORIN promotes progression of gastric cancer by mediating the ERK1/2 MAPK pathway

The serine protease CORIN catalyzes pro-atrial natriuretic peptide (pro-ANP) into an active ANP and maintains homeostasis of the internal environment. However, it is unclear whether CORIN participates in the regulation of tumor progression. We analyzed the expression profile of CORIN in gastric cancer tissues (GCs) and adjacent nontumoral tissues (NTs). We investigated the prognostic value of CORIN in GC patients. We characterized the in vitro and in vivo activity of CORIN in cultured GC cells with gain-of-function and loss-of-function experiments. The underlying mechanism was explored by using bioinformatics, a signaling antibody array, and confirmative western blot analyses, as well as rescue experiments with highly selective small-molecule inhibitors targeting the ERK1/2 MAPK signaling pathway. CORIN was upregulated in GCs than in NTs. Overexpression of CORIN was correlated with unfavorable prognoses in patients with GC. Ectopic expression of CORIN was promoted, whereas silencing of CORIN suppressed proliferation, colony formation, migration and invasion of GC cells, and tumor growth in vivo. Overexpression of CORIN-induced epithelial-mesenchymal transition (EMT) and activation of the ERK1/2 MAPK signaling pathway, while silencing of CORIN yielded opposite results. The in vitro tumor-promoting potency of CORIN could be antagonized by selective inhibitors targeting the ERK1/2 MAPK pathway. In conclusion, CORIN is a potential prognostic marker and therapeutic target for GC patients, which may promote tumor progression by mediating the ERK1/2 MAPK signaling pathway and EMT in GC cells.

Circulating Liquid Biopsy Biomarkers in Glioblastoma: Advances and Challenges

Gliomas, particularly glioblastoma (GBM), represent the most prevalent and aggressive tumors of the central nervous system (CNS). Despite recent treatment advancements, patient survival rates remain low. The diagnosis of GBM traditionally relies on neuroimaging methods such as magnetic resonance imaging (MRI) or computed tomography (CT) scans and postoperative confirmation via histopathological and molecular analysis. Imaging techniques struggle to differentiate between tumor progression and treatment-related changes, leading to potential misinterpretation and treatment delays. Similarly, tissue biopsies, while informative, are invasive and not suitable for monitoring ongoing treatments. These challenges have led to the emergence of liquid biopsy, particularly through blood samples, as a promising alternative for GBM diagnosis and monitoring. Presently, blood and cerebrospinal fluid (CSF) sampling offers a minimally invasive means of obtaining tumor-related information to guide therapy. The idea that blood or any biofluid tests can be used to screen many cancer types has huge potential. Tumors release various components into the bloodstream or other biofluids, including cell-free nucleic acids such as microRNAs (miRNAs), circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), proteins, extracellular vesicles (EVs) or exosomes, metabolites, and other factors. These factors have been shown to cross the blood-brain barrier (BBB), presenting an opportunity for the minimally invasive monitoring of GBM as well as for the real-time assessment of distinct genetic, epigenetic, transcriptomic, proteomic, and metabolomic changes associated with brain tumors. Despite their potential, the clinical utility of liquid biopsy-based circulating biomarkers is somewhat constrained by limitations such as the absence of standardized methodologies for blood or CSF collection, analyte extraction, analysis methods, and small cohort sizes. Additionally, tissue biopsies offer more precise insights into tumor morphology and the microenvironment. Therefore, the objective of a liquid biopsy should be to complement and enhance the diagnostic accuracy and monitoring of GBM patients by providing additional information alongside traditional tissue biopsies. Moreover, utilizing a combination of diverse biomarker types may enhance clinical effectiveness compared to solely relying on one biomarker category, potentially improving diagnostic sensitivity and specificity and addressing some of the existing limitations associated with liquid biomarkers for GBM. This review presents an overview of the latest research on circulating biomarkers found in GBM blood or CSF samples, discusses their potential as diagnostic, predictive, and prognostic indicators, and discusses associated challenges and future perspectives.

Construction of a TAN-associated risk score model with integrated multi-omics data analysis and clinical validation in gastric cancer

AIMS

An increasing number of studies have highlighted the biological significance of neutrophil activation and polarization in tumor progression. However, the characterization of tumor-associated neutrophils (TANs) is inadequately investigated.

MATERIALS AND METHODS

Patients' expression profiles were obtained from TCGA, GEO, and IMvigor210 databases. Six algorithms were used to assess immune cell infiltration. RNA sequencing was conducted to evaluate the differentially expressed genes between induced N1- and N2-like neutrophils. A TAN-associated risk score (TRS) model was established using a combination of weighted gene co-expression network analysis (WGCNA) and RNA-seq data and further assessed in pan-cancer. A clinical cohort of 117 GC patients was enrolled to assess the role of TANs in GC via immunohistochemistry (IHC).

KEY FINDINGS

A TRS signature was built with 10 TAN-related genes (TRGs) and most TRGs were highly abundant in the TANs of the GC microenvironment. The TRS model could accurately predict patients' prognosis, as well as their responses to chemotherapy and immunotherapy. The TRS was positively correlated with pro-tumor immune cells and exhibited negative relationship with anti-tumor immune cells. Additional functional analyses revealed that the signature was positively related to pro-tumor and immunosuppression pathways, such as the hypoxia pathway, across pan-cancer. Furthermore, our clinical cohort demonstrated TANs as an independent prognostic factor for GC patients.

SIGNIFICANCE

This study constructed and confirmed the value of a novel TRS model for prognostic prediction of GC and pan-cancer. Further evaluation of TRS and TANs will help strengthen the understanding of the tumor microenvironment and guide more effective therapeutic strategies.

Dual inhibition of SUMOylation and MEK conquers MYC-expressing KRAS-mutant cancers by accumulating DNA damage

BACKGROUND

KRAS mutations frequently occur in cancers, particularly pancreatic ductal adenocarcinoma, colorectal cancer, and non-small cell lung cancer. Although KRASG12C inhibitors have recently been approved, effective precision therapies have not yet been established for all KRAS-mutant cancers. Many treatments for KRAS-mutant cancers, including epigenome-targeted drugs, are currently under investigation. Small ubiquitin-like modifier (SUMO) proteins are a family of small proteins covalently attached to and detached from other proteins in cells via the processes called SUMOylation and de-SUMOylation. We assessed whether SUMOylation inhibition was effective in KRAS-mutant cancer cells.

METHODS

The efficacy of the first-in-class SUMO-activating enzyme E inhibitor TAK-981 (subasumstat) was assessed in multiple human and mouse KRAS-mutated cancer cell lines. A gene expression assay using a TaqMan array was used to identify biomarkers of TAK-981 efficacy. The biological roles of SUMOylation inhibition and subsequent regulatory mechanisms were investigated using immunoblot analysis, immunofluorescence assays, and mouse models.

RESULTS

We discovered that TAK-981 downregulated the expression of the currently undruggable MYC and effectively suppressed the growth of MYC-expressing KRAS-mutant cancers across different tissue types. Moreover, TAK-981-resistant cells were sensitized to SUMOylation inhibition via MYC-overexpression. TAK-981 induced proteasomal degradation of MYC by altering the balance between SUMOylation and ubiquitination and promoting the binding of MYC and Fbxw7, a key factor in the ubiquitin-proteasome system. The efficacy of TAK-981 monotherapy in immunocompetent and immunodeficient mouse models using a mouse-derived CMT167 cell line was significant but modest. Since MAPK inhibition of the KRAS downstream pathway is crucial in KRAS-mutant cancer, we expected that co-inhibition of SUMOylation and MEK might be a good option. Surprisingly, combination treatment with TAK-981 and trametinib dramatically induced apoptosis in multiple cell lines and gene-engineered mouse-derived organoids. Moreover, combination therapy resulted in long-term tumor regression in mouse models using cell lines of different tissue types. Finally, we revealed that combination therapy complementally inhibited Rad51 and BRCA1 and accumulated DNA damage.

CONCLUSIONS

We found that MYC downregulation occurred via SUMOylation inhibition in KRAS-mutant cancer cells. Our findings indicate that dual inhibition of SUMOylation and MEK may be a promising treatment for MYC-expressing KRAS-mutant cancers by enhancing DNA damage accumulation.

A-to-I RNA co-editing predicts clinical outcomes and is associated with immune cells infiltration in hepatocellular carcinoma

Aberrant RNA editing has emerged as a pivotal factor in the pathogenesis of hepatocellular carcinoma (HCC), but the impact of RNA co-editing within HCC remains underexplored. We used a multi-step algorithm to construct an RNA co-editing network in HCC, and found that HCC-related RNA editings are predominantly centralized within the network. Furthermore, five pairs of risk RNA co-editing events were significantly correlated with the overall survival in HCC. Based on presence of risk RNA co-editings resulted in the categorization of HCC patients into high-risk and low-risk groups. Disparities in immune cell infiltrations were observed between the two groups, with the high-risk group exhibiting a greater abundance of exhausted T cells. Additionally, seven genes associated with risk RNA co-editing pairs were identified, whose expression effectively differentiates HCC tumor samples from normal ones. Our research offers an innovative perspective on the etiology and potential therapeutics for HCC.

Dissecting the pleiotropic roles of reactive oxygen species (ROS) in lung cancer: From carcinogenesis toward therapy

Lung cancer is a major cause of morbidity and mortality. The specific pulmonary structure to directly connect with ambient air makes it more susceptible to damage from airborne toxins. External oxidative stimuli and endogenous reactive oxygen species (ROS) play a crucial role in promoting lung carcinogenesis and development. The biological properties of higher ROS levels in tumor cells than in normal cells make them more sensitive and vulnerable to ROS injury. Therefore, the strategy of targeting ROS has been proposed for cancer therapy for decades. However, it is embarrassing that countless attempts at ROS-based therapies have had very limited success, and no FDA approval in the anticancer list was mechanistically based on ROS manipulation. Even compared with the untargetable proteins, such as transcription factors, ROS are more difficult to be targeted due to their chemical properties. Thus, the pleiotropic roles of ROS provide therapeutic potential for anticancer drug discovery, while a better dissection of the mechanistic action and signaling pathways is a prerequisite for future breakthroughs. This review discusses the critical roles of ROS in cancer carcinogenesis, ROS-inspired signaling pathways, and ROS-based treatment, exemplified by lung cancer. In particular, an eight considerations rule is proposed for ROS-targeting strategies and drug design and development.

TCF19 promotes cell proliferation and tumor formation in lung cancer by activating the Raf/MEK/ERK signaling pathway

OBJECTIVE

This study aimed to investigate TCF19's role in lung cancer development, specifically its involvement in the RAF/MEK/ERK signaling pathway.

METHODS

Lung cancer tissue analysis revealed significant TCF19 overexpression. In vitro experiments using A549 and Hop62 cells with TCF19 overexpression demonstrated enhanced cell growth. Transgenic mouse models confirmed TCF19's role in primary tumor development. Transcriptome sequencing identified altered gene expression profiles, linking TCF19 to RAF/MEK/ERK pathway activation. Functional assays elucidated underlying mechanisms, revealing increased phosphorylation of Raf1, MEK1/2, and ERK1/2. Inhibiting RAF1 or ERK through shRaf1 or ERK inhibitor reduced cell cycle-related proteins and inhibited TCF19-overexpressing cell growth.

RESULTS

TCF19 was identified as an oncogene in lung carcinoma, specifically impacting the RAF/MEK/ERK pathway. Elevated TCF19 levels in lung cancer suggest targeting TCF19 or its associated pathways as a promising strategy for disease management.

CONCLUSION

This study unveils TCF19's oncogenic role in lung cancer, emphasizing its modulation of the RAF/MEK/ERK pathway and presenting a potential therapeutic target for TCF19-overexpressing lung cancers.

Clonal competition assays identify fitness signatures in cancer progression and resistance in multiple myeloma

Multiple myeloma (MM) is a genetically heterogeneous disease and the management of relapses is one of the biggest clinical challenges. TP53 alterations are established high-risk markers and are included in the current disease staging criteria. KRAS is the most frequently mutated gene affecting around 20% of MM patients. Applying Clonal Competition Assays (CCA) by co-culturing color-labeled genetically modified cell models, we recently showed that mono- and biallelic alterations in TP53 transmit a fitness advantage to the cells. Here, we report a similar dynamic for two mutations in KRAS (G12A and A146T), providing a biological rationale for the high frequency of KRAS and TP53 alterations at MM relapse. Resistance mutations, on the other hand, did not endow MM cells with a general fitness advantage but rather presented a disadvantage compared to the wild-type. CUL4B KO and IKZF1 A152T transmit resistance against immunomodulatory agents, PSMB5 A20T to proteasome inhibition. However, MM cells harboring such lesions only outcompete the culture in the presence of the respective drug. To better prevent the selection of clones with the potential of inducing relapse, these results argue in favor of treatment-free breaks or a switch of the drug class given as maintenance therapy. In summary, the fitness benefit of TP53 and KRAS mutations was not treatment-related, unlike patient-derived drug resistance alterations that may only induce an advantage under treatment. CCAs are suitable models for the study of clonal evolution and competitive (dis)advantages conveyed by a specific genetic lesion of interest, and their dependence on external factors such as the treatment.

Assessment of KRASG12C inhibitors for colorectal cancer

Colorectal cancer (CRC) is a highly prevalent and lethal cancer worldwide. Approximately 45% of CRC patients harbor a gain-in-function mutation in KRAS. KRAS is the most frequently mutated oncogene accounting for approximately 25% of all human cancers. Gene mutations in KRAS cause constitutive activation of the KRAS protein and MAPK/AKT signaling, resulting in unregulated proliferation and survival of cancer cells and other aspects of malignant transformation, progression, and metastasis. While KRAS has long been considered undruggable, the FDA recently approved two direct acting KRAS inhibitors, Sotorasib and Adagrasib, that covalently bind and inactivate KRASG12C. Both drugs showed efficacy for patients with non-small cell lung cancer (NSCLC) diagnosed with a KRASG12C mutation, but for reasons not well understood, were considerably less efficacious for CRC patients diagnosed with the same mutation. Thus, it is imperative to understand the basis for resistance to KRASG12C inhibitors, which will likely be the same limitations for other mutant specific KRAS inhibitors in development. This review provides an update on clinical trials involving CRC patients treated with KRASG12C inhibitors as a monotherapy or combined with other drugs. Mechanisms that contribute to resistance to KRASG12C inhibitors and the development of novel RAS inhibitors with potential to escape such mechanisms of resistance are also discussed.

DUSP22 inhibits lung tumorigenesis by suppression of EGFR/c-Met signaling

DUSP22, an atypical dual-specificity phosphatase enzyme, plays a significant role in regulating multiple kinase signaling pathways by dephosphorylation. Our study demonstrated that decreased DUSP22 expression is associated with shorter disease-free survival, advanced TNM (tumor, lymph nodes, and metastasis), cancer stage, and higher tumor grade in lung adenocarcinoma (LUAD) patients. Exogenous DUSP22 expression reduces the colony-forming capacity of lung cancer cells and inhibits xenograft tumor growth primarily by targeting EGFR and suppressing its activity through dephosphorylation. Knockdown of DUSP22 using shRNA enhances EGFR dependency in HCC827 lung cancer cells and increases sensitivity to gefitinib, an EGFR inhibitor. Consistently, genetic deletion of DUSP22 enhances EGFRdel (exon 19 deletion)-driven lung tumorigenesis and elevates EGFR activity. Pharmacological inhibition of DUSP22 activates EGFR, ERK1/2, and upregulates downstream PD-L1 expression. Additionally, lentiviral deletion of DUSP22 by shRNA enhances lung cancer cell migration through EGFR/c-Met and PD-L1-dependent pathways. Gefitinib, an EGFR inhibitor, mechanistically suppresses migration induced by DUSP22 deletion and inhibits c-Met activity. Furthermore, cabozantinib, a c-Met inhibitor, reduces migration and attenuates EGFR activation caused by DUSP22 deletion. Collectively, our findings support the hypothesis that loss of DUSP22 function in lung cancer cells confers a survival advantage by augmenting EGFR signaling, leading to increased activation of downstream c-Met, ERK1/2, and PD-L1 axis, ultimately contributing to the progression of advanced lung cancer.

Determining the ERK-regulated phosphoproteome driving KRAS-mutant cancer

To delineate the mechanisms by which the ERK1 and ERK2 mitogen-activated protein kinases support mutant KRAS-driven cancer growth, we determined the ERK-dependent phosphoproteome in KRAS-mutant pancreatic cancer. We determined that ERK1 and ERK2 share near-identical signaling and transforming outputs and that the KRAS-regulated phosphoproteome is driven nearly completely by ERK. We identified 4666 ERK-dependent phosphosites on 2123 proteins, of which 79 and 66%, respectively, were not previously associated with ERK, substantially expanding the depth and breadth of ERK-dependent phosphorylation events and revealing a considerably more complex function for ERK in cancer. We established that ERK controls a highly dynamic and complex phosphoproteome that converges on cyclin-dependent kinase regulation and RAS homolog guanosine triphosphatase function (RHO GTPase). Our findings establish the most comprehensive molecular portrait and mechanisms by which ERK drives KRAS-dependent pancreatic cancer growth.

Off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their antitumor activity in RAS-driven cancers

Aberrant activation of RAS/MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities. Unfortunately, treatment-provoked adaptive resistance mechanisms inevitably develop, limiting their therapeutic potential. As a central node essential for receptor tyrosine kinase-mediated RAS activation, SHP2 has emerged as an attractive cancer target. Consequently, many SHP2 allosteric inhibitors are now in clinical testing. Here we discovered a previously unrecognized off-target effect associated with SHP2 allosteric inhibitors. We found that these inhibitors accumulate in the lysosome and block autophagic flux in an SHP2-independent manner. We showed that off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their antitumor activity. We also demonstrated that SHP2 allosteric inhibitors harboring this off-target activity not only suppress oncogenic RAS signaling but also overcome drug resistance such as MAPK rebound and protective autophagy in response to RAS/MAPK pathway blockage. Finally, we exemplified a therapeutic framework that harnesses both the on- and off-target activities of SHP2 allosteric inhibitors for improved treatment of mutant RAS-driven and drug-resistant malignancies such as pancreatic and colorectal cancers.

RNA Sequencing and Bioinformatics Analysis Reveals the Downregulation of DNA Replication Genes by Morindone in Colorectal Cancer Cells

Morindone, a natural anthraquinone compound, has been reported to have significant pharmacological properties in different cancers. However, its anticancer effects in colorectal cancer (CRC) and the underlying molecular mechanisms remain obscure. In this study, RNA sequencing was used to assess the differentially expressed genes (DEGs) following morindone treatment in two CRC cell lines, HCT116 and HT29 cells. Functional enrichment analysis of overlapping DEGs revealed that negative regulation of cell development from biological processes and the MAPK signalling pathway were the most significant Gene Ontology terms and Kyoto Encyclopaedia of Genes and Genome pathway, respectively. Seven hub genes were identified among the overlapping genes, including MCM5, MCM6, MCM10, GINS2, POLE2, PRIM1, and WDHD1. All hub genes were found downregulated and involved in DNA replication fork. Among these, GINS2 was identified as the most cancer-dependent gene in both cells with better survival outcomes. Validation was performed on seven hub genes with rt-qPCR, and the results were consistent with the RNA sequencing findings. Collectively, this study provides corroboration of the potential therapeutic benefits and suitable pharmacological targets of morindone in the treatment of CRC.

Differential contribution for ERK1 and ERK2 kinases in BRAFV600E-triggered phenotypes in adult mouse models

The BRAF gene is mutated in a plethora of human cancers. The majority of such molecular lesions result in the expression of a constitutively active BRAF variant (BRAFV600E) which continuously bolsters cell proliferation. Although we recently addressed the early effects triggered by BRAFV600E-activation, the specific contribution of ERK1 and ERK2 in BRAFV600E-driven responses in vivo has never been explored. Here we describe the first murine model suitable for genetically dissecting the ERK1/ERK2 impact in multiple phenotypes induced by ubiquitous BRAFV600E-expression. We unveil that ERK1 is dispensable for BRAFV600E-dependent lifespan shortening and for BRAFV600E-driven tumor growth. We show that BRAFV600E-expression provokes an ERK1-independent lymphocyte depletion which does not rely on p21CIP1-induced cell cycle arrest and is unresponsive to ERK-chemical inhibition. Moreover, we also reveal that ERK1 is dispensable for BRAFV600E-triggered cytotoxicity in lungs and that ERK-chemical inhibition abrogates some of these detrimental effects, such as DNA damage, in Club cells but not in pulmonary lymphocytes. Our data suggest that ERK1/ERK2 contribution to BRAFV600E-driven phenotypes is dynamic and varies dependently on cell type, the biological function, and the level of ERK-pathway activation. Our findings also provide useful insights into the comprehension of BRAFV600E-driven malignancies pathophysiology as well as the consequences in vivo of novel ERK pathway-targeted anti-cancer therapies.

Novel RAF-directed approaches to overcome current clinical limits and block the RAS/RAF node

Mutations in the RAS-RAF-MEK-ERK pathway are frequent alterations in cancer and RASopathies, and while RAS oncogene activation alone affects 19% of all patients and accounts for approximately 3.4 million new cases every year, less frequent alterations in the cascade's downstream effectors are also involved in cancer etiology. RAS proteins initiate the signaling cascade by promoting the dimerization of RAF kinases, which can act as oncoproteins as well: BRAFV600E is the most common oncogenic driver, mutated in the 8% of all malignancies. Research in this field led to the development of drugs that target the BRAFV600-like mutations (Class I), which are now utilized in clinics, but cause paradoxical activation of the pathway and resistance development. Furthermore, they are ineffective against non-BRAFV600E malignancies that dimerize and could be either RTK/RAS independent or dependent (Class II and III, respectively), which are still lacking an effective treatment. This review discusses the recent advances in anti-RAF therapies, including paradox breakers, dimer-inhibitors, immunotherapies, and other novel approaches, critically evaluating their efficacy in overcoming the therapeutic limitations, and their putative role in blocking the RAS pathway.

Clinical characteristic and survival outcomes of patients with advanced NSCLC according to KRAS mutational status in the French real-life ESME cohort

PURPOSE

The RAS/MEK signaling pathway is essential in carcinogenesis and frequently altered in non-small-cell lung cancer (NSCLC), notably by KRAS mutations (KRASm) that affect 25%-30% of non-squamous NSCLC. This study aims to explore the impact of KRASm subtypes on disease phenotype and survival outcomes.

PATIENTS AND METHODS

We conducted a retrospective analysis of the French Epidemiological Strategy and Medical Economics database for advanced or metastatic lung cancer from 2011 to 2021. Patient demographics, histology, KRASm status, treatment strategies, and outcomes were assessed.

RESULTS

Of 10 177 assessable patients for KRAS status, 17.6% had KRAS p.G12C mutation, 22.6% had KRAS non-p.G12C mutation, and 59.8% were KRASwt. KRASm patients were more often smokers (96.3%) compared with KRASwt (85.8%). A higher proportion of programmed death-ligand 1 ≥50% was found for KRASm patients: 43.5% versus 38.0% (P < 0.01). KRASm correlated with poorer outcomes. First-line median progression-free survival was shorter in the KRASm than the KRASwt cohort: 4.0 months [95% confidence interval (CI) 3.7-4.3 months] versus 5.1 months (95% CI 4.8-5.3 months), P < 0.001. First-line overall survival was shorter for KRASm than KRASwt patients: 12.6 months (95% CI 11.6-13.6 months) versus 15.4 months (95% CI 14.6-16.2 months), P = 0.012. First-line chemoimmunotherapy offered better overall survival in KRAS p.G12C (48.8 months) compared with KRAS non-p.G12C (24.0 months) and KRASwt (22.5 months) patients. Second-line overall survival with immunotherapy was superior in the KRAS p.G12C subgroup: 12.6 months (95% CI 8.1-18.6 months) compared with 9.4 months (95% CI 8.0-11.4 months) for KRAS non-p.G12C and 9.6 months (8.4-11.0 months) for KRASwt patients.

CONCLUSION

We highlighted distinct clinical profiles and survival outcomes according to KRASm subtypes. Notably KRAS p.G12C mutations may provide increased sensitivity to immunotherapy, suggesting potential therapeutic implications for sequencing or combination of therapies. Further research on the impact of emerging KRAS specific inhibitors are warranted in real-world cohorts.

Different lactate metabolism subtypes reveal heterogeneity in clinical outcomes and immunotherapy in lung adenocarcinoma patients

Background

The excessive accumulation of lactate within the tumor microenvironment (TME) has been demonstrated to facilitate tumor advancement and evade the immune system. Nonetheless, the metabolic status of lactate in lung adenocarcinoma (LUAD) remains uncertain.

Method

By analyzing the transcriptome profile of patients with LUAD, we created a lactate metabolism score (LMS) to predict survival. We then conducted a comprehensive examination of the biological functions and immune infiltration among different LMS patient groups. Moreover, we assessed the LMS predictive efficacy in chemotherapy and immunotherapy. Finally, we validated the detrimental phenotypic effects of SLC16A3 on LUAD cell lines (PC9 and A549) through in vitro experiments. We collected clinical samples to assess the prognostic impact of SLC16A3.

Results

We constructed an LMS model with 6 lactate metabolism regulatory factors using LASSO regression. The high LMS model indicates worse clinical outcomes for LUAD patients. High LMS patients are associated with metabolic dysregulation and increased infiltration of M0 and M1 macrophages. Low LMS patients are related to upregulated citric acid metabolism pathways and memory immune cells. High LMS patients are suitable for traditional chemotherapy, while patients with low LMS are more likely to benefit from immunotherapy. Lastly, downregulating SLC16A3 significantly reduces the proliferative and invasive capabilities of LUAD cell lines. Clinical cohort shows that patients with high expression of SLC16A3 have a worse prognosis.

Conclusions

The LMS model constructed based on the lactate metabolism pathway displays high effectiveness in predicting the outcome of patients with LUAD. LMS can offer direction regarding chemotherapy as well as immunotherapy in LUAD.

The UBE2F-CRL5ASB11-DIRAS2 axis is an oncogene and tumor suppressor cascade in pancreatic cancer cells

UBE2F, a neddylation E2, neddylates CUL5 to activate cullin-RING ligase-5, upon coupling with neddylation E3 RBX2/SAG. Whether and how UBE2F controls pancreatic tumorigenesis is previously unknown. Here, we showed that UBE2F is essential for the growth of human pancreatic cancer cells with KRAS mutation. In the mouse KrasG12D pancreatic ductal adenocarcinoma (PDAC) model, Ube2f deletion suppresses cerulein-induced pancreatitis, and progression of acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia. Mechanistically, Ube2f deletion inactivates the Mapk-c-Myc signals via blocking ubiquitylation of Diras2, a substrate of CRL5Asb11 E3 ligase. Biologically, DIRAS2 suppresses growth and survival of human pancreatic cancer cells harboring mutant KRAS, and Diras2 deletion largely rescues the phenotypes induced by Ube2f deletion. Collectively, Ube2f or Diras2 plays a tumor-promoting or tumor-suppressive role in the mouse KrasG12D PDAC model, respectively. The UBE2F-CRL5ASB11 axis could serve as a valid target for pancreatic cancer, whereas the levels of UBE2F or DIRAS2 may serve as prognostic biomarkers for PDAC patients.

Facts and Hopes in Immunotherapy Strategies Targeting Antigens Derived from KRAS Mutations

In this commentary, we advance the notion that mutant KRAS (mKRAS) is an ideal tumor neoantigen that is amenable for targeting by the adaptive immune system. Recent progress highlights key advances on various fronts that validate mKRAS as a molecular target and support further pursuit as an immunological target. Because mKRAS is an intracellular membrane localized protein and not normally expressed on the cell surface, we surmise that proteasome degradation will generate short peptides that bind to HLA class I (HLA-I) molecules in the endoplasmic reticulum for transport through the Golgi for display on the cell surface. T-cell receptors (TCR)αβ and antibodies have been isolated that specifically recognize mKRAS encoded epitope(s) or haptenated-mKRAS peptides in the context of HLA-I on tumor cells. Case reports using adoptive T-cell therapy provide proof of principle that KRAS G12D can be successfully targeted by the immune system in patients with cancer. Among the challenges facing investigators is the requirement of precision medicine to identify and match patients to available mKRAS peptide/HLA therapeutics and to increase the population coverage by targeting additional mKRAS epitopes. Ultimately, we envision mKRAS-directed immunotherapy as an effective treatment option for selected patients that will complement and perhaps synergize with small-molecule mKRAS inhibitors and targeted mKRAS degraders.

Opportunities for targeted therapies: trametinib as a therapeutic approach to canine oral squamous cell carcinomas

Oral tumors are relatively common in dogs, and canine oral squamous cell carcinoma (COSCC) is the most prevalent oral malignancy of epithelial origin. COSCC is locally aggressive with up to 20% of patients showing regional or distant metastasis at the time of diagnosis. The treatment of choice most typically involves wide surgical excision. Although long-term remission is possible, treatments are associated with significant morbidity and can negatively impact functionality and quality of life. OSCCs have significant upregulation of the RAS-RAF-MEK-MAPK signaling axis, and we had previously hypothesized that small-molecule inhibitors that target RAS signaling might effectively inhibit tumor growth and progression. Here, we demonstrate that the MEK inhibitor trametinib, an FDA-approved drug for human cancers, significantly blocks the growth of several COSCC cell lines established from current patient tumor samples. We further show clinical evidence that the drug is able to cause significant tumor regression in some patients with spontaneously occurring COSCC. Given the limited treatment options available and the high rate of owner rejection of these offered options, these findings provide new hope that more acceptable treatment options may soon enter the veterinary clinic.

Molecular characterization of m6A RNA methylation regulators with features of immune dysregulation in IgA nephropathy

The role of RNA N6-methyladenosine (m6A) modification in immunity is being elucidated. This study aimed to explore the potential association between m6A regulators and the immune microenvironment in IgA nephropathy (IgAN). The expression profiles of 24 m6A regulators in 107 IgAN patients were obtained from the Gene Expression Omnibus (GEO) database. The least absolute shrinkage and selection operator (LASSO) regression and logistic regression analysis were utilized to construct a model for distinguishing IgAN from control samples. Based on the expression levels of m6A regulators, unsupervised clustering was used to identify m6A-induced molecular clusters in IgAN. Gene set enrichment analysis (GSEA) and immunocyte infiltration among different clusters were examined. The gene modules with the highest correlation for each of the three clusters were identified by weighted gene co-expression network analysis (WGCNA). A model containing 10 m6A regulators was developed using LASSO and logistic regression analyses. Three molecular clusters were determined using consensus clustering of 24 m6A regulators. A decrease in the expression level of YTHDF2 in IgAN samples was significantly negatively correlated with an increase in resting natural killer (NK) cell infiltration and was positively correlated with the abundance of M2 macrophage infiltration. The risk scores calculated by the nomogram were significantly higher for cluster-3, and the expression levels of m6A regulators in this cluster were generally low. Immunocyte infiltration and pathway enrichment results for cluster-3 differed significantly from those for the other two clusters. Finally, the expression of YTHDF2 was significantly decreased in IgAN based on immunohistochemical staining. This study demonstrated that m6A methylation regulators play a significant role in the regulation of the immune microenvironment in IgAN. Based on m6A regulator expression patterns, IgAN can be classified into multiple subtypes, which might provide additional insights into novel therapeutic methods for IgAN.

Targeting RAF dimers in RAS mutant tumors: From biology to clinic

RAS mutations occur in approximately 30% of tumors worldwide and have a poor prognosis due to limited therapies. Covalent targeting of KRAS G12C has achieved significant success in recent years, but there is still a lack of efficient therapeutic approaches for tumors with non-G12C KRAS mutations. A highly promising approach is to target the MAPK pathway downstream of RAS, with a particular focus on RAF kinases. First-generation RAF inhibitors have been authorized to treat BRAF mutant tumors for over a decade. However, their use in RAS-mutated tumors is not recommended due to the paradoxical ERK activation mainly caused by RAF dimerization. To address the issue of RAF dimerization, type II RAF inhibitors have emerged as leading candidates. Recent clinical studies have shown the initial effectiveness of these agents against RAS mutant tumors. Promisingly, type II RAF inhibitors in combination with MEK or ERK inhibitors have demonstrated impressive efficacy in RAS mutant tumors. This review aims to clarify the importance of RAF dimerization in cellular signaling and resistance to treatment in tumors with RAS mutations, as well as recent progress in therapeutic approaches to address the problem of RAF dimerization in RAS mutant tumors.

Fertility and reproductive concerns related to the new generation of cancer drugs and the clinical implication for young individuals undergoing treatments for solid tumors

The treatment landscape of solid tumors has changed markedly in the last years. Molecularly targeted treatments and immunotherapies have been implemented and have, in many cancers, lowered the risk of relapse and prolonged survival. Patients with tumors harboring specific targetable molecular alterations or mutations are often of a younger age, and hence future fertility and family building can be important concerns in this group. However, there are great uncertainties regarding the effect of the new drugs on reproductive functions, including fertility, pregnancy and lactation and how young patients with cancers, both women and men should be advised. The goal with this review is to gather the current knowledge regarding oncofertility and the different novel therapies, including immune checkpoint inhibitors, antibody-drug conjugates, small molecules and monoclonal antibody targeted therapies. The specific circumstances and reproductive concerns in different patient groups where novel treatments have been broadly introduced are also discussed, including those with melanoma, lung, breast, colorectal and gynecological cancers. It is clear, that more awareness is needed regarding potential drug toxicity on reproductive tissues, and it is of essence that individuals are informed based on current expertise and on available fertility preservation methods.

Network-based analysis identifies potential therapeutic ingredients of Chinese medicines and their mechanisms toward lung cancer

Lung cancer is one of the most common malignant tumors around the world, which has the highest mortality rate among all cancers. Traditional Chinese medicine (TCM) has attracted increased attention in the field of lung cancer treatment. However, the abundance of ingredients in Chinese medicines presents a challenge in identifying promising ingredient candidates and exploring their mechanisms for lung cancer treatment. In this work, two network-based algorithms were combined to calculate the network relationships between ingredient targets and lung cancer targets in the human interactome. Based on the enrichment analysis of the constructed disease module, key targets of lung cancer were identified. In addition, molecular docking and enrichment analysis of the overlapping targets between lung cancer and ingredients were performed to investigate the potential mechanisms of ingredient candidates against lung cancer. Ten potential ingredients against lung cancer were identified and they may have similar effect on the development of lung cancer. The results obtained from this study offered valuable insights and provided potential avenues for the development of novel drugs aimed at treating lung cancer.

The crosstalk between oncogenic signaling and ferroptosis in cancer

Ferroptosis, a novel form of cell death regulation, was identified in 2012. It is characterized by unique features that differentiate it from other types of cell death, including necrosis, apoptosis, autophagy, and pyroptosis. Ferroptosis is defined by an abundance of iron ions and lipid peroxidation, resulting in alterations in subcellular structures, an elevation in reactive oxygen species (ROS), a reduction in glutathione (GSH) levels, and an augmentation in Fe (II) cytokines. Ferroptosis, a regulated process, is controlled by an intricate network of signaling pathways, where multiple stimuli can either enhance or hinder the process. This review primarily examines the defensive mechanisms of ferroptosis and its interaction with the tumor microenvironment. The analysis focuses on the pathways that involve AMPK, p53, NF2, mTOR, System Xc-, Wnt, Hippo, Nrf2, and cGAS-STING. The text discusses the possibilities of employing a combination therapy that targets several pathways for the treatment of cancer. It emphasizes the necessity for additional study in this field.