EGFR Signaling Research Articles

TNO155 is a selective SHP2 inhibitor to target PTPN11-dependent oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is known to be driven by multiple intricated receptor tyrosine kinases (RTKs) including EGFR, PI3K/AKT and MAPK signaling pathways. However, whilst targeting EGFR with cetuximab has been approved for the treatment of OSCC, other single-agent inhibitors of the RTKs have shown modest effects in improving survival. From the genome-wide CRISPR/Cas9 screen on 21 OSCC cell lines, we have identified PTPN11 among the top essential genes in OSCC. PTPN11 encodes for SHP2, a phosphatase that acts as a master signal transducer, downstream of various RTKs. Although PTPN11 overexpression has been reported in OSCC, little is known about its role as an essential gene for OSCC survival and its potential as a therapeutic target. Herein, we confirmed that PTPN11 is an essential gene in OSCC where its deletion significantly impacted cell survival. We evaluated three SHP2 inhibitors on 21 OSCC cell lines and found TNO155 to be significantly associated with CRISPR dependency score. We showed that TNO155 caused dose-dependent suppression on p-ERK and p-MEK, and suppresses the JAK/STAT pathway via downregulating p-JAK1, p-STAT1, p-STAT3. Furthermore, we confirmed that the combination of the mTOR inhibitor, everolimus with TNO155 is synergistic in OSCC. In summary, PTPN11 is a promising therapeutic target in OSCC that can be selectively targeted by SHP2 inhibitor such as TNO155. Our findings on the use of mTOR inhibitor, everolimus to overcome resistance to TNO155 are essential to inform on next phases of clinical trials which is warranted for the treatment of OSCC.

Effects of inorganic phosphate on stem cells isolated from human exfoliated deciduous teeth

Calcium phosphate-based materials (CaP) are introduced as potential dental pulp capping materials for deciduous teeth. The present study investigated the influence of inorganic phosphate (Pi) on regulating stem cells isolated from human exfoliated deciduous teeth (SHED). SHEDs were treated with Pi. Cell cycle progression and apoptosis were examined using flow cytometry analysis. Osteo/odontogenic and adipogenic differentiation were analyzed using alizarin red S and oil red O staining, respectively. The mRNA expression profile was investigated using a high-throughput RNA sequencing technique. Pi increased the late apoptotic cell population while cell cycle progression was not altered. Pi upregulated osteo/odontoblastic gene expression and enhanced calcium deposition. Pi-induced mineralization was reversed by pretreatment of cells with Foscarnet, or p38 inhibitor. Pi treatment inhibited adipogenic differentiation as determined by decreased PPARγ expression and reduced intracellular lipid accumulation. Bioinformatic analysis of gene expression profiles demonstrated several involved pathways, including PI3K/AKT, MAPK, EGFR, and VEGF signaling. In conclusion, Pi enhanced osteo/odontogenic but inhibited adipogenic differentiation in SHED.

Zongertinib (BI 1810631), an irreversible HER2 TKI, spares EGFR signaling and improves therapeutic response in preclinical models and patients with HER2-driven cancers.

Mutations in HER2 occur in 2-4% of non-small cell lung cancer (NSCLC) and confer poor prognosis. ERBB-targeting tyrosine kinase inhibitors, approved for treating other HER2-dependent cancers, are ineffective in HER2 mutant NSCLC due to dose-limiting toxicities or suboptimal potency. We report the discovery of zongertinib (BI 1810631), a covalent HER2 inhibitor. Zongertinib potently and selectively blocks HER2, while sparing EGFR, and inhibits the growth of cells dependent on HER2 oncogenic driver events, including HER2-dependent human cancer cells resistant to trastuzumab deruxtecan. Zongertinib displays potent anti-tumor activity in HER2-dependent human NSCLC xenograft models and enhances the activities of antibody-drug conjugates and KRASG12C inhibitors, without causing obvious toxicities. The preclinical efficacy of zongertinib translates in objective responses in patients with HER2-dependent tumors, including cholangiocarcinoma (SDC4-NRG1 fusion) and breast cancer (V777L HER2 mutation) thus supporting the ongoing clinical development of zongertinib.

Transient proliferation by reversible YAP-mediated increase of the cyclin D1/p27 ratio.

YAP signaling controls cell cycle entry and exit by up- and down-regulating the cyclin D1/p27 ratio above and below a conserved thresholdYAP-induced proliferation is intrinsically transient since contact inhibition of YAP suppresses EGFR signaling after a delay to reduce this cyclin D1/p27 ratioYAP can still be robustly inhibited after Merlin/NF2 ablation but only at higher local cell densityThe YAP-regulated cyclin D1/p27 ratio is primarily controlled by MEK-ERK rather than mTOR activity.

The Prospective role of lapatinib as an adjuvant therapy in prevalent cancers: Insights from in silico analysis targeting EGFR and HER2

IntroductionVarious pieces of evidence suggest an elevation in the levels of EGFR and HER2 in different cancers leading to the proliferation, invasion, and metastasis of cancer cells. In this study, we conducted a comprehensive investigation into the expression alterations of these two receptors in various cancers using in silico data. In addition, we investigated the therapeutic potential of lapatinib as an inhibitor of these receptors in various cancer types. MethodsRNAseq data for prevalent cancers were downloaded from The Cancer Genome Atlas (TCGA). After initial preprocessing, expression changes of HER2, EGFR, and candidate genes—identified based on their association with EGFR and HER2 signaling pathways—were examined. Human protein atlas data were utilized to assess the protein expression of HER2 and EGFR. GSE129254 was employed to identify molecular pathways and candidate genes associated with lapatinib. The protein-protein interaction network was used to identify lapatinib-influenced hub genes. Clinical data for common cancers were used to investigate the correlation between the expression of candidate genes and patients' mortality rates by Cox regression test. ResultsThe findings clearly indicated a significant increase in the expression levels of HER2 and EGFR in cancers such as kidney, lung, breast, bladder, pancreas, head and neck, stomach, and endometrial, both at the mRNA and protein levels (p-value <0.01). Additionally, more than 30 % of samples in some cancers showed a twofold increase in HER2 or EGFR expression. The analysis of GSE129254 data revealed that lapatinib reduces the expression of numerous genes associated with cell proliferation. METTL1, LYAR, LTV1, CCND1, NOP2, and DDX21 were identified as hub genes related to the effect of lapatinib. Our results demonstrated that many hub genes exhibited elevated expression in candidate cancers, and the upregulation of some of them was correlated with poor prognosis. ConclusionOur results indicate an upregulation in the expression levels of HER2 and EGFR in certain common cancers, suggesting that lapatinib, in addition to breast cancer, could be considered for the treatment of these cancers. Furthermore, we demonstrated that some genes with increased expression in prevalent cancers and associated with poor prognosis have the potential to be modulated by lapatinib.

Vitexin Inhibits TNBC Progression and Metastasis by Modulating Macrophage Polarization Through EGFR Signaling.

Triple-negative breast cancer (TNBC) lacks sensitivity to endocrine and targeted therapies, exhibiting high recurrence and poor prognosis postchemotherapy. Tumor-associated macrophages (TAMs) play a crucial role in cancer progression. Vitexin, a compound with diverse pharmacological effects including anti-cancer activity, remains unexplored in its impact on TAMs during TNBC development. This study aimed to investigate vitexin's effect on TNBC, its regulation of macrophage polarization (M1 vs. M2), and the underlying EGFR/PI3K/AKT/mTOR pathway. Our results demonstrated that vitexin suppressed the proliferation and invasion of TNBC cells (MDA-MB-231 and BT549) while inducing macrophage mediators that further inhibited cancer cell migration. Vitexin also promoted M1 polarization and suppressed M2 polarization, affecting EGFR phosphorylation and downstream signaling. In vivo, vitexin inhibited tumor growth, favoring M1 polarization and suppressing M2 polarization, with synergistic effects when combined with doxorubicin (Dox). These findings offer novel insights into vitexin's potential in TNBC treatment.

EGFR-dependent actomyosin patterning coordinates morphogenetic movements between tissues in Drosophila melanogaster.

The movements that give rise to the body's structure are powered by cell shape changes and rearrangements that are coordinated at supracellular scales. How such cellular coordination arises and integrates different morphogenetic programs is unclear. Using quantitative imaging, we found a complex pattern of adherens junction (AJ) levels in the ectoderm prior to gastrulation onset in Drosophila. AJ intensity exhibited a double-sided gradient, with peaks at the dorsal midline and ventral neuroectoderm. We show that this dorsal-ventral AJ pattern is regulated by epidermal growth factor (EGF) signaling and that this signal is required for ectoderm cell movement during mesoderm invagination and axis extension. We identify AJ levels and junctional actomyosin as downstream effectors of EGFR signaling. Overall, our study demonstrates an EGF-patterned mechanical feedback mechanism that coordinates tissue folding and convergent extension to facilitate embryo-wide gastrulation movements.

NoxO1 regulates EGFR signaling by its interaction with Erbin

NADPH oxidase organizer 1 (NoxO1) is a scaffold cytoplasmic subunit of the reactive oxygen species (ROS) forming Nox1 complex and involved in angiogenesis, differentiation, and atherosclerosis.We found that overexpression of NoxO1 without simultaneous overexpression of any other component of the active Nox1 complex inhibited EGF-induced wound closure and signaling, while NoxO1 KO yielded the opposite effect. Accordingly, we hypothesize NoxO1 to exert Nox1 independent functions.Using the BioID technique, we identified ErbB2 interacting protein (Erbin) as novel interaction partner of NoxO1. Colocalization of NoxO1 with EGFR, as well as with Erbin validated this finding. EGF treatment interrupted colocalization of NoxO1 and EGFR. EGF mediated kinase activation was delayed in NoxO1 overexpressing cells, while knockout of NoxO1 had the opposite effect.In conclusion, Erbin was identified as a novel NoxO1 interacting protein. Through the subsequent interaction of NoxO1 and EGFR, NoxO1 interferes with EGF signaling. The results of this study suggest a potential role of NoxO1 as an adaptor protein with functions beyond the well-established enabling of Nox1 mediated ROS formation.

A Novel Tryptanthrin Derivative D6 Induces Apoptosis and DNA Damage in Non-small-cell Lung Cancer Cells Through Regulating the EGFR Pathway.

Non-small-cell lung cancer is a prevalent malignancy associated with significant morbidity and mortality rates. Tryptanthrin and its derivatives have exhibited potent antitumor activity. This study aims to investigate the inhibitory effect of a novel synthesized tryptanthrin derivative D6 on proliferation and the possible mechanism of human non-small cell lung cancer cell lines (A549) in vitro. In this study, MTT assay, cell migration, colony formation assay, cell cycle analysis, cell apoptosis, JC- 1 staining assay, reactive oxygen species analysis, proteomics, western blotting, high content screening and absorption titrations analysis were performed. We found that D6 inhibited both the proliferation and migration, induced cell cycle arrest in the G2/M phase, increased levels of ROS, decreased mitochondrial membrane potential, and promoted apoptosis in A549 cells. Further mechanistic studies found that D6 reduced EGFR expression in A549 cells and inhibited the EGFR pathway by decreasing phosphorylation levels of EGFR, Stat3, AKT and Erk1/2. Moreover, DNA damage induced by D6 involved an increase in p53/MDM2 ratio and concentration-dependent accumulation of micronuclei. D6 demonstrated significant antitumor activity against A549 cells by inhibiting the EGFR signaling pathway, inducing DNA damage, and subsequently leading to oxidative stress, apoptosis, and cell cycle arrest. Our findings suggest that D6 exhibits potential as an NSCLC drug, owing to its attributes such as antiproliferative activity and ability to induce apoptosis by attenuating the EGFR-mediated signaling pathway.

Development of a FUT8 Inhibitor with Cellular Inhibitory Properties.

Core fucosylation is catalyzed by α-1,6-fucosyltransferase (FUT8), which fucosylates the innermost GlcNAc of N-glycans. Given the association of FUT8 with various diseases including cancer, selective FUT8 inhibitors applicable to in vivo or cell-based systems are highly sought-after. Here, we report the discovery of a compound that selectively inhibits FUT8 in cell-based assays. High-throughput screening revealed a FUT8-inhibiting pharmacophore, and further structural optimization yielded an inhibitor with a KD of 49 nM. Notably, this binding occurs only in the presence of GDP (a product of the enzymatic reaction catalyzed by FUT8). Mechanistic studies suggested that this inhibitor generates a highly reactive naphthoquinone methide derivative at the binding site in FUT8, which subsequently reacts with FUT8. Furthermore, prodrug derivatization of this inhibitor improved its stability, enabling suppression of core fucose expression and subsequent EGFR and T-cell signaling in cell-based assays, paving the way for the development of drugs targeting core fucosylation.

The microprotein HDSP promotes gastric cancer progression through activating the MECOM-SPINK1-EGFR signaling axis

The presence of noncanonical open reading frames within lncRNAs (long non-coding RNAs) suggests their potential for translation, yielding various functional peptides or proteins. However, the existence and specific roles of these products in gastric cancer remain largely unclear. Here we identify the HOXA10-HOXA9-derived small protein (HDSP) in gastric cancer through comprehensive analysis and experimental validation, including mass spectrometry and western blotting. HDSP exhibits high expression and oncogenic roles in gastric cancer. Mechanistically, HDSP blocks TRIM25-mediated ubiquitination and degradation by interacting with MECOM, leading to MECOM accumulation and enhanced SPINK1 transcription-a gene promoting cancer via the EGFR signaling pathway. Furthermore, MECOM fosters HOXA10-HOXA9 transcription, establishing a feedback loop activating SPINK1-EGFR signaling. HDSP knockdown inhibits tumor growth in a PDX (patient-derived xenograft) model, and infusion of an artificially synthesized HDSP peptide as a neoantigen enhances immune cell-mediated anti-tumor efficacy against gastric cancer in vitro and in vivo. These findings propose HDSP as a potential therapeutic target or neoantigen candidate for gastric cancer treatment.

Lumican/Lumikine Promotes Healing of Corneal Epithelium Debridement by Upregulation of EGFR Ligand Expression via Noncanonical Smad-Independent TGFβ/TBRs Signaling.

The synthetic peptide of lumican C-terminal 13 amino acids with the cysteine replaced by an alanine, hereafter referred to as lumikine (LumC13C-A: YEALRVANEVTLN), binds to TGFβ type I receptor/activin-like kinase5 (TBR1/ALK5) in the activated TGFβ receptor complex to promote corneal epithelial wound healing. The present study aimed to identify the minimum essential amino acid epitope necessary to exert the effects of lumikine via ALK5 and to determine the role of the Y (tyrosine) residue for promoting corneal epithelium wound healing. This study also aimed to determine the signaling pathway(s) triggered by lumican-ALK5 binding. For such, adult Lum knockout (Lum-/-) mice (~8-12 weeks old) were subjected to corneal epithelium debridement using an Agerbrush®. The injured eyes were treated with 10 µL eye drops containing 0.3 µM synthetic peptides designed based on the C-terminal region of lumican for 5-6 h. To unveil the downstream signaling pathways involved, inhibitors of the Alk5 and EGFR signaling pathways were co-administered or not. Corneas isolated from the experimental mice were subjected to whole-mount staining and imaged under a ZEISS Observer to determine the distance of epithelium migration. The expression of EGFR ligands was determined following a scratch assay with HTCE (human telomerase-immortalized cornea epithelial cells) in the presence or not of lumikine. Results indicated that shorter LumC-terminal peptides containing EVTLN and substitution of Y with F in lumikine abolishes its capability to promote epithelium migration indicating that Y and EVTLN are essential but insufficient for Lum activity. Lumikine activity is blocked by inhibitors of Alk5, EGFR, and MAPK signaling pathways, while EGF activity is only suppressed by EGFR and MAPK inhibitors. qRT-PCR of scratched HTCE cells cultures treated with lumikine showed upregulated expression of several EGFR ligands including epiregulin (EREG). Treatment with anti-EREG antibodies abolished the effects of lumikine in corneal epithelium debridement healing. The observations suggest that Lum/lumikine binds Alk5 and promotes the noncanonical Smad-independent TGFβ/TBRs signaling pathways during the healing of corneal epithelium debridement.

Insulin receptor substrate 1 is a novel member of EGFR signaling in pancreatic cells

Pancreatic ductal adenocarcinoma is an extremely incurable cancer type characterized by cells with highly proliferative capacity and resistance against the current therapeutic options. Our study reveals that IRS1 acts as a bridging molecule between EGFR and IGFR/InsR signalization providing a potential mechanism for the interplay between signaling pathways and bypassing EGFR-targeted or IGFR/InsR-targeted therapies. The analysis of IRS1 phosphorylation status in four pancreatic cell lines identified the impact of EGFR signaling on IRS1 activation in comparison with InsR/IGFR signaling. Significantly reduced viability was observed in IRS1-silenced cells even upon EGF stimulation showing the critical role of IRS1 in the EGFR signaling network in both malignant and normal pancreatic cells. This study also demonstrated that EGFR binds directly to IRS1 and at least on two tyrosine sites, Y612 and Y896, IRS1 becomes phosphorylated in response to EGF stimulation. Mechanistically, the EGFR-mediated phosphorylation of IRS1 can further activate the MAPK signaling pathway with the recruitment of GRB2 protein. Collectively, in this study, IRS1 was identified as a crucial regulator in the EGFR signaling suggesting IRS1 as a potential target for more durable responses to targeted PDAC therapy.

Design, Synthesis, Anti-Proliferative Effects, and Mechanistic Details of Fluorine-Containing Biguanide Derivatives with Various Carbon Rings

Introduction/Objective: Biguanide derivatives are small molecules with promising antitumor activity. However, the effect of different carbon rings at the end of one guanide group of these compounds on anti-proliferation activity is unknown. Therefore, we synthesized novel fluorine- containing biguanide compounds with various carbon rings, evaluated their anticancer activities, and explored their anti-proliferative mechanisms. Methods: Guanidine derivatives containing trifluoromethoxy or 3,4-difluorophenyl with nine different carbon rings were synthesized using established chemical methods. The phenyl side chain was fixed to trifluoromethoxy or 3,4-difluorophenyl with changes in the number of cyclic aminocyclic carbons. The effects of these derivatives were evaluated using MTT and clonogenic assays, while the underlying mechanisms were investigated by analyzing protein expression levels via western blotting. Results: This study analyzed the effects of new biguanide derivatives on cell growth in three different cell lines: HepG2, Ovcar3, and T24. The results showed that T24 cells were the most sensitive cell line to these biguanides. All biguanide derivatives significantly inhibited the growth of T24 cells, while compound 4b exhibited the strongest inhibition in all three cell lines by MTT assay. The inhibitory effects of 4b were further confirmed using colony formation experiments. Western blotting results indicated that the representative biguanide derivative, 4b, inhibited the EGFR signaling pathway, thereby inhibiting tumor growth. Conclusion: 1a-5a and 1b-4b, the cyclooctyl-containing 3,4-difluorophenyl biguanide analogs, have demonstrated significant potential in developing novel anticancer drugs. The 3,4- difluorophenyl biguanide containing cyclooctyl showed the best antitumor activity among the nine derivatives. This finding offers a novel perspective in developing anticancer drugs and a further improvement in biguanide activity in the future.

Loss of HD-PTP function results in lipodystrophy, defective cellular signaling and altered lipid homeostasis.

His domain protein tyrosine phosphatase (HD-PTP; also known as PTPN23) facilitates function of the endosomal sorting complexes required for transport (ESCRTs) during multivesicular body (MVB) formation. To uncover its role in physiological homeostasis, embryonic lethality caused by a complete lack of HD-PTP was bypassed through generation of hypomorphic mice expressing reduced protein, resulting in animals that are viable into adulthood. These mice exhibited marked lipodystrophy and decreased receptor-mediated signaling within white adipose tissue (WAT), involving multiple prominent pathways including RAS/MAPK, phosphoinositide 3-kinase (PI3K)/AKT and receptor tyrosine kinases (RTKs), such as EGFR. EGFR signaling was dissected in vitro to assess the nature of defective signaling, revealing decreased trans-autophosphorylation and downstream effector activation, despite normal EGF binding. This corresponds to decreased plasma membrane cholesterol and increased lysosomal cholesterol, likely resulting from defective endosomal maturation necessary for cholesterol trafficking and homeostasis. The ESCRT components Vps4 and Hrs have previously been implicated in cholesterol homeostasis; thus, these findings expand knowledge on which ESCRT subunits are involved in cholesterol homeostasis and highlight a non-canonical role for HD-PTP in signal regulation and adipose tissue homeostasis.

Abstract PR-19: Cell polarity proteins as novel regulators of macropinocytosis

Abstract Macropinocytosis has emerged as a nutrient-scavenging pathway that cancer cells exploit to survive the nutrient-deprived conditions of the tumor microenvironment. Cancer cells are especially reliant on glutamine for their survival, and in pancreatic ductal adenocarcinoma (PDAC) cells, glutamine deficiency can enhance the stimulation of macropinocytosis, allowing the cells to escape metabolic stress through the production of extracellular-protein-derived amino acids. Here, we identify the atypical protein kinase C (aPKC) enzymes, PKCz and PKCi, as novel regulators of macropinocytosis. In normal epithelial cells, aPKCs are known to regulate cell polarity in association with the scaffold proteins Par3 and Par6, controlling the function of several targets, including the microtubule-associated Par1 kinases. In PDAC cells, we identify that each of these cell polarity proteins are required for glutamine stress-induced macropinocytosis. Mechanistically, we find that the aPKCs are regulated by EGFR signaling or by the transcription factor CREM to promote the relocation of Par3 to microtubules, facilitating macropinocytosis in a dynein-dependent manner. Importantly, we determine that cell fitness impairment caused by aPKC depletion in glutamine stress is rescued by the restoration of macropinocytosis and that aPKCs support PDAC growth in vivo. These results identify a previously unappreciated role for the cell polarity protein network in the regulation of macropinocytosis and provide a better understanding of the mechanistic underpinnings that control macropinocytic uptake in the context of metabolic stress. Citation Format: Guillem Lambies Barjau, Szu-Wei Lee, Karen Duong-Polk Duong-Polk, David Dawson, Cheska Marie Galapate, Swetha Maganti, Cosimo Commisso. Cell polarity proteins as novel regulators of macropinocytosis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr PR-19.

Catalytically distinct IDH1 mutants tune phenotype severity in tumor models.

Mutations in isocitrate dehydrogenase 1 (IDH1) impart a neomorphic reaction that produces D-2-hydroxyglutarate (D2HG), which can inhibit DNA demethylases to drive tumorigenesis. Mutations affect residue R132 and display distinct catalytic profiles for D2HG production. We show that catalytic efficiency of D2HG production is greater in IDH1 R132Q than R132H mutants, and expression of R132Q in cellular and xenograft models leads to higher D2HG concentrations in cells, tumors, and sera compared to R132H. Though expression of IDH1 R132Q leads to hypermethylation in DNA damage pathways, DNA hypomethylation is more notable when compared to R132H expression. Transcriptome analysis shows increased expression of many pro-tumor pathways upon expression of IDH1 R132Q versus R132H, including transcripts of EGFR and PI3K signaling pathways. Thus, IDH1 mutants appear to modulate D2HG levels via altered catalysis, resulting in distinct epigenetic and transcriptomic consequences where higher D2HG levels appear to be associated with more aggressive tumors.

A new exploration: characterization of the differentiation trajectory of prostate cancer cells

Prostate cancer is one of the most common malignant tumors in men, and in-depth study of its gene expression patterns is crucial for understanding the formation and development of prostate cancer. Although single-cell transcriptomics has deeply explored the heterogeneous expression characteristics of prostate cancer, given that normal epithelial cells themselves have different states of differentiation, these normal differentiation characteristics may lead to confusion with heterogeneous tumor characteristics. In this study, we used single-cell data from the GEO database to analyze in detail the heterogeneity of prostate cancer tumor cells/tumor-associated epithelium cells (TAECs), with a particular focus on the differentiation state of epithelial cells in matching normal tissue. We found that after subtype pairing analysis of normal tissue and tumor tissue epithelium based on differentiation status, the characteristics identified later were not consistent with the general characteristics originally exhibited by different TAECs subpopulations. Among them, all TAECs subpopulations showed P53 enrichment and downregulation of the apoptotic pathway, and expressed higher levels of EGFR, ERBB2, interferon receptors, MIF, and cell adhesion-related signals; through transcription factor regulatory network analysis, we observed that YY1, NKX3-1, and EHF had higher transcriptional activity in TAECs subpopulations than normal epithelial cells at the same differentiation stage, while ATF3 was the opposite. Among them, YY1 may act as an upstream regulator of the MIF signaling pathway, and ATF3 is a key upstream transcriptional regulator of differentially expressed genes in the P53 and apoptotic pathways. Immune infiltration analysis showed that the above four transcription factors were significantly correlated with the infiltration of immune cells in prostate cancer, and pan-cancer analysis showed that their expression-related survival risks were widely present in different cancers. It is worth noting that this is merely a preliminary, exploratory study, which inevitably has some deficiencies and limitations. Despite this, this study is committed to bringing a novel and unique perspective to the field through this work, with the hope of opening up new levels of understanding and stimulating more in-depth research and discussion.

GOLM1 dictates acquired Lenvatinib resistance by a GOLM1-CSN5 positive feedback loop upon EGFR signaling activation in hepatocellular carcinoma.

Lenvatinib is a multiple receptor tyrosine kinases inhibitor (TKI) authorized for first-line treatment of hepatocellular carcinoma (HCC). However, Lenvatinib resistance is common in HCC clinical treatment, highlighting the urgent need to understand mechanisms of resistance. Here, we identified Golgi membrane protein 1 (GOLM1), a type II transmembrane protein originally located in the Golgi apparatus, as a novel regulator of Lenvatinib resistance. We found GOLM1 was overexpressed in Lenvatinib resistant human HCC cell lines, blood and HCC samples. Additionally, GOLM1 overexpression contributes to Lenvatinib resistance and HCC progression in vitro and in vivo. Mechanistically, GOLM1 upregulates CSN5 expression through EGFR-STAT3 pathway. Reversely, CSN5 deubiquitinates and stabilizes GOLM1 protein by inhibiting ubiquitin-proteasome pathway of GOLM1. Furthermore, clinical specimens of HCC showed a positive correlation between the activation of the GOLM1-EGFR-STAT3-CSN5 axis. Finally, GOLM1 knockdown was found to act in synergy with Lenvatinib in subcutaneous and orthotopic mouse model. Overall, these findings identify a mechanism of resistance to Lenvatinib treatment for HCC, highlight an effective predictive biomarker of Lenvatinib response in HCC and show that targeting GOLM1 may improve the clinical benefit of Lenvatinib.

The Pax transcription factor EGL-38 links EGFR signaling to assembly of a cell-type specific apical extracellular matrix in the Caenorhabditis elegans vulva.

The surface of epithelial tissues is covered by an apical extracellular matrix (aECM). The aECMs of different tissues have distinct compositions to serve distinct functions, yet how a particular cell type assembles the proper aECM is not well understood. We used the cell-type specific matrix of the C. elegans vulva to investigate the connection between cell identity and matrix assembly. The vulva is an epithelial tube composed of seven cell types descending from EGFR/Ras-dependent (1°) and Notch-dependent (2°) lineages. Vulva aECM contains multiple Zona Pellucida domain (ZP) proteins, which are a common component of aECMs across life. ZP proteins LET-653 and CUTL-18 assemble on 1° cell surfaces, while NOAH-1 assembles on a subset of 2° surfaces. All three ZP genes are broadly transcribed, indicating that cell-type specific ZP assembly must be determined by features of the destination cell surface. The paired box (Pax) transcription factor EGL-38 promotes assembly of 1° matrix and prevents inappropriate assembly of 2° matrix, suggesting that EGL-38 promotes expression of one or more ZP matrix organizers. Our results connect the known signaling pathways and various downstream effectors to EGL-38/Pax expression and the ZP matrix component of vulva cell fate execution. We propose that dedicated transcriptional networks may contribute to cell-appropriate assembly of aECM in many epithelial organs.