Mitogenic Activity Research Articles

Ganjiang Huangqin Huanglian Renshen Decoction protects against ulcerative colitis by modulating inflammation, oxidative stress, and gut microbiota

BackgroundUlcerative colitis (UC) is a disease that is difficult to treat and has been associated with high rates of recurrence. Moreover, the current medications for UC induce serious side effects following prolonged use. Ganjiang Huangqin Huanglian Renshen Decoction (GJHQHLRSD), has been traditionally used to treat UC. However, its protective mechanisms have not been fully studied. PurposeIn this study the mechanisms by which GJHQHLRSD treats UC was investigated. MethodsThe GJHQHLRSD and GJHQHLRSD drug-containing serum (GJHQHLRSD-DS) were characterized using LC-MS/MS. The therapeutic effect of GJHQHLRSD on dextran sodium sulfate (DSS)-induced UC was explored by assessing various parameters including intestinal flora 16S rRNA, intestinal barrier function, oxidative stress (OS) response, inflammatory cytokines, colonic histopathological injury, colon length, disease activity index (DAI) and body weight. ResultsTreatment with GJHQHLRSD increased body weight, ameliorated colon length shortening and edema, reduced the DAI score, improved the pathological injury, down-regulated the levels of IL-1β, IL-6, IL-8, TNF-α, LPS, LDH, TLR4, and NLRP3, and up-regulated the ZO-1 and Occludin levels in UC mice. It also decreased intestinal oxidative stress in UC mice and improved mitogenic activity by modulating mitochondrial ultrastructure as well as the expression level of PINK1, LC3-II/Ⅰ, Beclin-1, p62, and Parkin proteins. In addition, we found that the effects of GJHQHLRSD on UC mice were inhibited by 3-MA.GJHQHLRSD treatment reduced the imbalance of intestinal flora in UC mice, by regulating the inflammation and oxidative stress. ConclusionThese findings suggested that GJHQHLRSD effectively attenuated inflammatory responses, inhibited the TLR4/NF-κB/NLRP3 signalling, oxidative stress, and modulated the gut microbiota, and alleviated the DSS-induced UC symptoms, making it a promising and innovative therapeutic option for the treatment of UC.

Structural Basis for Antibody Neutralization of Pertussis Toxin.

Antibodies neutralizing pertussis toxin (PT) prevent the severe clinical symptoms associated with infection by Bordetella pertussis . However, the molecular basis of effective PT-targeted immunity is poorly understood. To gain insight into PT-inhibitory mechanisms, we determined the cryo-electron microscopy structure of genetically detoxified PT (PTg) with two potently neutralizing antibodies to precisely define their epitopes. Carbohydrate-binding studies show that the hu11E6-binding surface on PT interacts with N-linked glycans and that blocking these interactions prevents PT's T cell mitogenic activities. Hu1B7 binds an epitope near the S1 active site that includes S5 contacts but these do not appear important for neutralization. This work identifies PT-neutralizing epitopes and supports inclusion of the hu1B7 and hu11E6 epitopes in next-generation vaccines and PT-based immunogens.

Senescent cells inhibit mouse myoblast differentiation via the SASP-lipid 15d-PGJ2 mediated modification and control of HRas

Senescent cells are characterized by multiple features such as increased expression of senescence-associated β-galactosidase activity (SA β-gal) and cell cycle inhibitors such as p21 or p16. They accumulate with tissue damage and dysregulate tissue homeostasis. In the context of skeletal muscle, it is known that agents used for chemotherapy such as Doxorubicin (Doxo) cause buildup of senescent cells, leading to the inhibition of tissue regeneration. Senescent cells influence the neighboring cells via numerous secreted factors which form the senescence-associated secreted phenotype (SASP). Lipids are emerging as a key component of SASP that can control tissue homeostasis. Arachidonic acid-derived lipids have been shown to accumulate within senescent cells, specifically 15d-PGJ2, which is an electrophilic lipid produced by the non-enzymatic dehydration of the prostaglandin PGD2. This study shows that 15d-PGJ2 is also released by Doxo-induced senescent cells as an SASP factor. Treatment of skeletal muscle myoblasts with the conditioned medium from these senescent cells inhibits myoblast fusion during differentiation. Inhibition of L-PTGDS, the enzyme that synthesizes PGD2, diminishes the release of 15d-PGJ2 by senescent cells and restores muscle differentiation. We further show that this lipid post-translationally modifies Cys184 of HRas in C2C12 mouse skeletal myoblasts, causing a reduction in the localization of HRas to the Golgi, increased HRas binding to Ras Binding Domain (RBD) of RAF Kinase (RAF-RBD), and activation of cellular Mitogen Activated Protein (MAP) kinase–Extracellular Signal Regulated Kinase (Erk) signaling (but not the Akt signaling). Mutating C184 of HRas prevents the ability of 15d-PGJ2 to inhibit the differentiation of muscle cells and control the activity of HRas. This work shows that 15d-PGJ2 released from senescent cells could be targeted to restore muscle homeostasis after chemotherapy.

Senescent cells inhibit mouse myoblast differentiation via the SASP-lipid 15d-PGJ2 mediated modification and control of HRas.

Senescent cells are characterized by multiple features such as increased expression of senescence-associated β-galactosidase activity (SA β-gal) and cell cycle inhibitors such as p21 or p16. They accumulate with tissue damage and dysregulate tissue homeostasis. In the context of skeletal muscle, it is known that agents used for chemotherapy such as Doxorubicin (Doxo) cause buildup of senescent cells, leading to the inhibition of tissue regeneration. Senescent cells influence the neighboring cells via numerous secreted factors which form the senescence-associated secreted phenotype (SASP). Lipids are emerging as a key component of SASP that can control tissue homeostasis. Arachidonic acid-derived lipids have been shown to accumulate within senescent cells, specifically 15d-PGJ2, which is an electrophilic lipid produced by the non-enzymatic dehydration of the prostaglandin PGD2. This study shows that 15d-PGJ2 is also released by Doxo-induced senescent cells as an SASP factor. Treatment of skeletal muscle myoblasts with the conditioned medium from these senescent cells inhibits myoblast fusion during differentiation. Inhibition of L-PTGDS, the enzyme that synthesizes PGD2, diminishes the release of 15d-PGJ2 by senescent cells and restores muscle differentiation. We further show that this lipid post-translationally modifies Cys184 of HRas in C2C12 mouse skeletal myoblasts, causing a reduction in the localization of HRas to the Golgi, increased HRas binding to Ras Binding Domain (RBD) of RAF Kinase (RAF-RBD), and activation of cellular Mitogen Activated Protein (MAP) kinase-Extracellular Signal Regulated Kinase (Erk) signaling (but not the Akt signaling). Mutating C184 of HRas prevents the ability of 15d-PGJ2 to inhibit the differentiation of muscle cells and control the activity of HRas. This work shows that 15d-PGJ2 released from senescent cells could be targeted to restore muscle homeostasis after chemotherapy.

The Role of Local Angiotensin II/Angiotensin Type 1 Receptor in Endometriosis: A Potential Target for New Treatment Approaches.

Endometriosis is a chronic inflammatory disorder described by the presence of functional endometrial-like tissues at extra-uterine locations that are related to chronic pelvic pain and infertility. Multiple molecular mechanisms, including inflammation, reactive oxygen species (ROS) generation, fibrotic reactions, and angiogenesis, are involved in the pathogenesis of endometriosis; however, the exact cause of this disorder still remains a matter of discussion. Recently, it has been shown that the local renin-angiotensin system (RAS) has been expressed in different tissues, like the gynecological tract, and alterations in its expression are associated with multiple pathological conditions like endometriosis. Angiotensin II (Ang II), as a main peptide of the RAS through angiotensin type 1 receptor (AT1R), upregulates signal transduction pathways such as nuclear factor kappa B (NF-κB), mitogen activation protein kinase (MAPK), and transforming growth factor beta (TGF-β) to promote inflammation, oxidative stress, and fibrogenesis. Angiotensin receptor blockers (ARBs) control high blood pressure, which is increased by excessive AT1R activity. Recently, it has been recognized that ARBs have tissue protective effects because of their anti-inflammatory and antifibrotic effects. In this review, we focused on the role of local Ang II/AT1R axis activity in endometriosis pathogenesis and justified the use of ARB agents as a potential therapeutic strategy to improve endometriosis.

FGF-21 Level is higher in patients with breast cancer, a candidate for a new biomarker?

Aims: Fibroblast Growth Factor 21 (FGF-21) is a member of the FGF family involved in biological processes such as embryonic development. cell growth. morphogenesis. tissue repair. tumour growth and invasion. with mitogenic and cytogenetic activity at 19q13.33.Breast cancer is a deadly and increasing disease in women. and recent studies have shown a relationship between some cancers. including breast cancer. and hormones secreted from adipose tissue.The aim of the present study was the measurement of FGF-21 levels in patients with breast cancer and its association with breast cancer. Methods: The study included 39 patients with newly diagnosed breast cancer and 39 healthy controls. During the patients’ routine blood tests. a venous blood sample was taken and the serum levels of FGF-21 were determined by ELISA. Results: Demographic and laboratory data were compared between the newly diagnosed breast cancer group and the control group. The control group consisted of 39 participants with a mean age of 52.49 ± 7.02 years. In the patient group. 39 participants with a mean age of 52.15 ± 6.21 years were included in the study. there was no statistical difference regarding age(p>0.05).In the control group. the mean FGF-21 level was 121.35 ± 88.4 pg/ml. while the mean FGF-21 level in the patient group was 171 ± 117.45 pg/ml. a statistically significant difference was detected(p value=0.036). Conclusion: FGF-21 is thought to have significant and beneficial effects on glucose. lipid and energy metabolism. as well as slowing the growth of cancer cells. and may later be used as a biological marker for breast cancer.

EPHB2 Knockdown Mitigated Myocardial Infarction by Inhibiting MAPK Signaling.

Myocardial infarction (MI) is a common type of cardiovascular disease. The incidence of ventricular remodeling dysplasia and heart failure increases significantly after MI. The objective of this study is to investigate whether erythropoietin hepatocellular receptor B2 (EPHB2) can regulate myocardial injury after MI and explore its regulatory pathways. EPHB2 is significantly overexpressed in the heart tissues of MI mice. The downregulation of EPHB2 alleviates the cardiac function damage after MI. Knockdown EPHB2 alleviates MI-induced myocardial tissue inflammation and apoptosis, and myocardial fibrosis in mice. EPHB2 knockdown significantly inhibits the activation of mitogen activated kinase-like protein (MAPK) pathway in MI mice. Moreover, EPHB2 overexpression significantly promotes the phosphorylation of MAPK pathway-related protein, which can be reversed by MAPK-IN-1 (an MAPK inhibitor) treatment. In conclusion, silencing EPHB2 can mitigate MI-induced myocardial injury by inhibiting MAPK signaling in mice, suggesting that targeting EPHB2 can be a promising therapeutic target for MI-induced myocardial injury.

Bone Marrow-Suppressive Treatment in Children Is Associated with Diminished IFN-γ Response from T Cells upon Polyclonal and Varicella Zoster Virus Peptide Stimulation.

Severe haematological diseases and lymphoid malignancies require bone marrow (BM)-suppressive treatments. Knowledge regarding the impact of BM-suppressive treatments on children's memory T cells is very limited. Memory T cells play a crucial role in defending against herpesviruses, which is particularly relevant in paediatric cancer care. We studied 53 children in total; 34 with cancer and 2 with severe haematological disorders, with some receiving BM-suppressive treatment with or without allogeneic-haematopoietic stem cell transplantation (allo-HSCT), alongside 17 healthy controls. We focused on peripheral blood proportions of memory T-cell subsets using flow cytometry and analysed cytokine-secreting T cells with a four-parameter FluoroSpot assay in response to T-cell mitogen and varicella zoster virus (VZV) peptides. Patients on BM-suppressive treatment showed increased clusters of differentiation (CD)4+ and CD8+ effector memory (TEM)/terminally differentiated effector (TEFF) T cells compared to the healthy controls. They also exhibited, amongst other things, when compared to the healthy controls, a reduced total number of cytokine-secreting cells, by means of interferon (IFN)-γ, interleukin (IL)-17A, IL-10, and IL-22, following mitogen activation. A diminished IFN-γ response among the children with BM-suppressive treatment was observed upon VZV-peptide stimulation, compared to the healthy children. Collectively, the findings herein indicate that the children who are undergoing or have finished BM-suppressive treatment display qualitative differences in their T-cell memory compartment, potentially increasing their susceptibility to severe viral infections and impacting their immunotherapy, which relies on the functional ability of autologous T cells.

Evaluating anticancer activity of emodin by enhancing antioxidant activities and affecting PKC/ADAMTS4 pathway in thioacetamide-induced hepatocellular carcinoma in rats

ABSTRACT Emodin is a naturally occurring anthraquinone derivative with a wide range of pharmacological activities, including neuroprotective and anti-inflammatory activities. We aim to assess the anticancer activity of emodin against hepatocellular carcinoma (HCC) in rat models using the proliferation, invasion, and angiogenesis biomarkers. After induction of HCC, assessment of the liver impairment and the histopathology of liver sections were investigated. Hepatic expression of both mRNA and protein of the oxidative stress biomarkers, HO-1, Nrf2; the mitogenic activation biomarkers, ERK5, PKCδ; the tissue destruction biomarker, ADAMTS4; the tissue homeostasis biomarker, aggregan; the cellular fibrinolytic biomarker, MMP3; and of the cellular angiogenesis biomarker, VEGF were measured. Emodin increased the survival percentage and reduced the number of hepatic nodules compared to the HCC group. Besides, emodin reduced the elevated expression of both mRNA and proteins of all PKC, ERK5, ADAMTS4, MMP3, and VEGF compared with the HCC group. On the other hand, emodin increased the expression of mRNA and proteins of Nrf2, HO-1, and aggrecan compared with the HCC group. Therefore, emodin is a promising anticancer agent against HCC preventing the cancer prognosis and infiltration. It works through many mechanisms of action, such as blocking oxidative stress, proliferation, invasion, and angiogenesis.

Lysophosphatidic Acid Stimulates Mitogenic Activity and Signaling in Human Neuroblastoma Cells through a Crosstalk with Anaplastic Lymphoma Kinase.

Lysophosphatidic acid (LPA) is a well-documented pro-oncogenic factor in different cancers, but relatively little is known on its biological activity in neuroblastoma. The LPA effects and the participation of the tyrosine kinase receptor anaplastic lymphoma kinase (ALK) in LPA mitogenic signaling were studied in human neuroblastoma cell lines. We used light microscopy and [3H]-thymidine incorporation to determine cell proliferation, Western blot to study intracellular signaling, and pharmacological and molecular tools to examine the role of ALK. We found that LPA stimulated the growth of human neuroblastoma cells, as indicated by the enhanced cell number, clonogenic activity, and DNA synthesis. These effects were curtailed by the selective ALK inhibitors NPV-TAE684 and alectinib. In a panel of human neuroblastoma cell lines harboring different ALK genomic status, the ALK inhibitors suppressed LPA-induced phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2), which are major regulators of cell proliferation. ALK depletion by siRNA treatment attenuated LPA-induced ERK1/2 activation. LPA enhanced ALK phosphorylation and potentiated ALK activation by the ALK ligand FAM150B. LPA enhanced the inhibitory phosphorylation of the tumor suppressor FoxO3a, and this response was impaired by the ALK inhibitors. These results indicate that LPA stimulates mitogenesis of human neuroblastoma cells through a crosstalk with ALK.

The heparin-binding domain of VEGF165 directly binds to integrin αvβ3 and VEGFR2/KDR D1: a potential mechanism of negative regulation of VEGF165 signaling by αvβ3.

VEGF-A is a key cytokine in tumor angiogenesis and a major therapeutic target for cancer. VEGF165 is the predominant isoform of VEGF-A, and it is the most potent angiogenesis stimulant. VEGFR2/KDR domains 2 and 3 (D2D3) bind to the N-terminal domain (NTD, residues 1-110) of VEGF165. Since removal of the heparin-binding domain (HBD, residues 111-165) markedly reduced the mitogenic activity of the growth factor, it has been proposed that the HBD plays a critical role in the mitogenicity of VEGF165. Here, we report that αvβ3 specifically bound to the isolated VEGF165 HBD but not to VEGF165 NTD. Based on docking simulation and mutagenesis, we identified several critical amino acid residues within the VEGF165 HBD required for αvβ3 binding, i.e., Arg123, Arg124, Lys125, Lys140, Arg145, and Arg149. We discovered that VEGF165 HBD binds to the KDR domain 1 (D1) and identified that Arg123 and Arg124 are critical for KDR D1 binding by mutagenesis, indicating that the KDR D1-binding and αvβ3-binding sites overlap in the HBD. Full-length VEGF165 mutant (R123A/R124A/K125A/K140A/R145A/R149A) defective in αvβ3 and KDR D1 binding failed to induce ERK1/2 phosphorylation, integrin β3 phosphorylation, and KDR phosphorylation and did not support proliferation of endothelial cells, although the mutation did not affect the KDR D2D3 interaction with VEGF165. Since β3-knockout mice are known to show enhanced VEGF165 signaling, we propose that the binding of KDR D1 to the VEGF165 HBD and KDR D2D3 binding to the VEGF165 NTD are critically involved in the potent mitogenicity of VEGF165. We propose that binding competition between KDR and αvβ3 to the VEGF165 HBD endows integrin αvβ3 with regulatory properties to act as a negative regulator of VEGF165 signaling.

Lost in Rotation: How TiO2 and ZnO Nanoparticles Disrupt Coordinated Epithelial Cell Rotation.

Coordinated cell movement is a cardinal feature in tissue organization that highlights the importance of cells working together as a collective unit. Disruptions to this synchronization can have far-reaching pathological consequences, ranging from developmental disorders to tissue repair impairment. Herein, it is shown that metal oxide nanoparticles (NPs), even at low and non-toxic doses (1 and 10µg mL-1), can perturb the coordinated epithelial cell rotation (CECR) in micropatterned human epithelial cell clusters via distinct nanoparticle-specific mechanisms. Zinc oxide (ZnO) NPs are found to induce significant levels of intracellular reactive oxygen species (ROS) to promote mitogenic activity. Generation of a new localized force field through changes in the cytoskeleton organization and an increase in cell density leads to the arrest of CECR. Conversely, epithelial cell clusters exposed to titanium dioxide (TiO2) NPs maintain their CECR directionality but display suppressed rotational speed in an autophagy-dependent manner. Thus, these findings reveal that nanoparticles can actively hijack the nano-adaptive responses of epithelial cells to disrupt the fundamental mechanics of cooperation and communication in a collective setting.

Investigating the novel role of sarcospan in modulating immune function in mice

Objective: The tetraspanin-like protein sarcospan (SSPN) has been shown to have an important in stabilizing muscle cell membranes and promoting cell adhesion. SSPN has documented expression in immune cells with the highest level of expression in B cells. Examination of SSPN-deficient (SSPN−/−) mice revealed alterations in important immune pathways, which remain uncharacterized. This led us to hypothesize that SSPN may play a role in modulating immune cell development and/or function. Methods: Flow cytometry was used to perform immunophenotyping of spleens obtained from SSPN−/− and WT mice. Cytokine analysis was performed using Luminex to assess cytokines that serve as important signals for immune cell maturation. Hematopoietic stem cells were isolated from red bone marrow and stimulated with phorbol myristate acetate (PMA), a mitogen and polyclonal activator of B cells, to assess whether SSPN deficiency affected their proliferative capacity. To determine whether SSPN plays a role in immunoglobulin isotype switching — antibody isotyping was performed. The presence of immune (antibody-antigen) complexes was investigated in kidney sections obtained from WT and SSPN−/− mice and visualized using biotinylated IgG and IgM antibodies. Autoantigen screening was also performed to assess whether SSPN−/− mice generated abnormal levels of autoantibodies that could be responsible for circulating antibody-antigen complexes. Results: The presence of SSPN on major immune cell types was confirmed using flow cytometry. In addition, flow cytometry analysis showed insignificant baseline differences in the percentage of B cells, T cells, plasmacytoid dendritic cells in SSPN−/− compared to WT spleens. One difference was noted in SSPN−/− females with increased counts of dendritic cells. Spleens in female SSPN−/− mice were found to be slightly larger compared to WT. Levels of B-cell activating factor (BAFF) and B-cell maturation antigen (BCMA) were elevated in SSPN−/− mice, therefore it is expected that SSPN−/− B cells received appropriate signals. Overall B cell proliferation was assessed by CD19+ and appeared unaffected by the absence of SSPN. Subtle increases in IgG1 and IgG2b were detected in SSPN−/− mice, however immunoglobulin isotypes were within normal ranges. SSPN−/− mice were also assessed for signs of dysregulated immune reactivity, evidenced by the presence of immune (antibody-antigen) complexes within filtration units of the kidney. Overall, male SSPN−/− mice were found to have a larger subset of increased IgG autoantibodies compared to male WT mice while female SSPN−/− mice exhibited a larger subset of increased IgM autoantibodies compared to female WT mice. Conclusions: This study examines potentially important functions of SSPN in the immune system. Overall, deletion of SSPN has not been found to affect maturation of major immune cell classes. However, SSPN does appear to influence formation of antigen-antibody complexes in mice, which may contribute to kidney dysfunction. These studies are ongoing and directed toward understanding the role SSPN plays in immune function. FSU Funding, Florida Department of Health, James and Esther King Biomedical Research Program #21K12. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Loss of ADAM15 in female mice does not worsen pressure overload cardiomyopathy, independent of ovarian hormones.

Cardiac hypertrophy is a common feature in several cardiomyopathies. We previously reported that loss of ADAM15 (disintegrin and metalloproteinase 15) worsened cardiac hypertrophy and dilated cardiomyopathy following cardiac pressure overload. Here, we investigated the impact of ADAM15 loss in female mice following cardiac pressure overload induced by transverse aortic constriction (TAC). Female Adam15-/- mice developed the same degree of cardiac hypertrophy, dilation, and dysfunction as the parallel female wild-type (WT) mice at 6 wk post-TAC. To determine if this is due to the protective effects of estrogen, which could mask the negative impact of Adam15 loss, WT and Adam15-/- mice underwent ovariectomy (OVx) 2 wk before TAC. Cardiac structure and function analyses were performed at 6 wk post-TAC. OVx similarly impacted females of both genotypes post-TAC. Calcineurin (Cn) activity was increased post-OVx-TAC, and more in Adam15-/- mice; however, this increase was not reflected in the total-to-phospho-NFAT levels. Integrin-α7 expression, which was upstream of Cn activation in male Adam15-/- -TAC mice, remained unchanged in female mice. However, activation of the mitogen-activated protein kinases (ERK, JNK, P38) was greater in Adam15-/--OVx-TAC than in WT-OVx-TAC mice. In addition, ADAM15 protein levels were significantly increased post-TAC in male but not in female WT mice. Myocardial fibrosis was comparable in non-OVx WT-TAC and Adam15-/- -TAC mice. OVx increased the perivascular fibrosis more in Adam15-/- compared with WT mice post-TAC. Our data demonstrate that loss of ovarian hormones did not fully replicate the male phenotype in the female Adam15-/- mice post-TAC. As ADAM15 levels were increased in males but not in females post-TAC, it is plausible that ADAM15 does not play a prominent role in post-TAC events in female mice. Our findings highlight the significance of factors other than sex hormones in mediating cardiomyopathies in females, which require a more thorough understanding.NEW & NOTEWORTHY Loss of ADAM15 in female mice, unlike the male mice, does not worsen the cardiomyopathy following cardiac pressure overload. Ovariectomy does not worsen the post-TAC cardiomyopathy in female Adam15-/- mice compared with female WT mice. Lack of deleterious impact of Adam15 deficiency in female mice is not because of the protective effects of ovarian hormones but could be due to a less prominent role of ADAM15 in cardiac response to post-TAC remodeling in female mice.

Abstract LB163: Discovery and characterization of QTX3544, a potent, selective, and orally bioavailable allosteric G12V preferring multi KRAS inhibitor

Abstract Oncogenic KRAS mutations occur in approximately 25% of all human cancers with KRAS G12V being one of the most frequently occurring variants, particularly in pancreatic, colorectal, and lung cancers. These oncogenic mutations cause sustained activation of the mitogen activated protein kinase (MAPK) pathway, which ultimately drives tumorigenesis. While newly approved covalent inhibitors to KRASG12C have demonstrated clinical benefit to patients harboring this mutation, there are no approved drugs targeting mutations beyond KRASG12C, highlighting a significant clinical need. Here we show that QTX3544 is a potent and orally bioavailable KRASG12V preferring multi KRAS inhibitor. QTX3544 exhibited picomolar binding affinity (0.08 nM) and SOS mediated nucleotide inhibition (0.07 nM) to the inactive form of KRASG12V. Furthermore, QTX3544 inhibited “on state” KRAS activity in both biochemical and cellular assays. In vitro, QTX3544 significantly inhibited downstream ERK phosphorylation and cell proliferation in KRASG12V driven cancer cell lines. Similar inhibitory effects were observed across additional mutant KRAS cancer cell lines, including KRAS G12A, KRAS G13D , and KRAS Q61H, among others. Notably, QTX3544 displayed no impact against HRAS, NRAS or BRAF mutant cells. In vivo, oral administration of QTX3544 achieved sustained systemic exposure required for efficacy, indicating potential durable inhibition of KRAS signaling. QTX3544 demonstrated dose dependent anti tumor efficacy and significant tumor regression in various KRASG12V driven xenograft models when administered orally twice daily (BID). The physiochemical profile of QTX3544 is favorable with good measured LogD, solubility, and permeability. QTX3544 exhibits weak Cytochrome P450 inhibition (direct and time dependent) with a favorable in vitro off target selectivity/safety profile. The systemic clearance in rats and dogs was moderate to high, respectively, with good oral bioavailability. QTX3544 was generally well tolerated in rat and dog repeat dose tolerability studies. In addition, QTX3544 showed good brain penetration in mice. Taken together, this preclinical characterization supports the advancement of QTX3544 into IND enabling studies for KRAS G12V mutant cancers. Citation Format: Yang W. Zhang, Elizabeth Donohue Vo, Pei Gan, Dave Rominger, Jillian M. Silva, Yang J. Zhang, Christopher Pan, Greg Lee, John M. Micozzi, Ben Reid, Brooke McDonough, Arghyotri Sinha, Audrey Hospital, Doug Krauth, Juan I. Luengo, Mike Kramer, Cameron Pitt, Hong Lin. Discovery and characterization of QTX3544, a potent, selective, and orally bioavailable allosteric G12V preferring multi KRAS inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB163.

Activity of Matrix Metalloproteinase-7 (MMP-7) Related to Heparin-Binding Epidermal Growth Factor (HB-EGF) Activation in Squamous Cell as Diagnostic Biomarker for Early Detection And Treatment of Maxilarian Cancer: Review Article

Background: Squamous cell carcinoma (SCC) has a higher chance of occurance and progression in maxillary sinus cancer than other paranasal sinus cancers (80%). Matrix metalloproteinase-7 (MMP-7) is a protease specified in collagen type IV degradation and Heparin Binding Epidermal Growth Factor activation, which causes an increase in squamous cell carcinoma proliferation and metastasis Methods: This review aims to identify the potential role of MMP-7 as a target for prevention and therapeutic modality to manage SCC sinus maxillary cancer. We did literature searching in several databases to elucidate the importance of the MMP-7 pathway in SCC sinus maxillary cancer progression. Results: : Increasing expression and activity of MMP-7 are associated with maxillary sinus cancer progression. Squamous cells, the most impacted in maxillary sinus cancer, sustain dysplasia due to heparin-binding epidermal growth factor (HB-EGF) activation into EGF by MMP-7 and Cluster of Differentiation 44 (CD44) binding complexes that trigger high proliferation and mitogenic activity. The therapeutic function of MMP-7 occurs by affecting the protein 53 (p53) in cancer cell apoptosis initiation by specific interaction with CD44. Conclusion: MMP-7 could be an alternative therapeutic target and potential treatment option for maxillary sinus cancer. Furthermore, more trials should be done to test the relevancy of MMP-7 uses as an SCC sinus maxillary cancer modality

RIP140 regulates transcription factor HES1 oscillatory expression and mitogenic activity in colon cancer cells.

The transcription factor receptor-interacting protein 140 (RIP140) regulates intestinal homeostasis and tumorigenesis through Wnt signaling. In this study, we investigated its effect on the Notch/HES1 signaling pathway. In colorectal cancer (CRC) cell lines, RIP140 positively regulated HES1 gene expression at the transcriptional level via a recombining binding protein suppressor of hairless (RBPJ)/neurogenic locus notch homolog protein 1 (NICD)-mediated mechanism. In support of these in vitro data, RIP140 and HES1 expression significantly correlated in mouse intestine and in a cohort of CRC samples, thus supporting the positive regulation of HES1 gene expression by RIP140. Interestingly, when the Notch pathway is fully activated, RIP140 exerted a strong inhibition of HES1 gene transcription controlled by the level of HES1 itself. Moreover, RIP140 directly interacts with HES1 and reversed its mitogenic activity in human CRC cells. In line with this observation, HES1 levels were associated with a better patient survival only when tumors expressed high levels of RIP140. Our data identify RIP140 as a key regulator of the Notch/HES1 signaling pathway, with a dual effect on HES1 gene expression at the transcriptional level and a strong impact on colon cancer cell proliferation.

The glucocorticoid dexamethasone alleviates allergic inflammation through a mitogen-activated protein kinase phosphatase-1-dependent mechanism in mice.

Glucocorticoids are widely used in the treatment of allergic and inflammatory diseases. Glucocorticoids have a widespread action on gene expression resulting in their pharmacological actions and also an array of adverse effects which limit their clinical use. It remains, however, to be studied which target gene effects are essential for the anti-allergic activity of glucocorticoids. Mitogen-activated protein kinase phosphatase-1 (MKP-1) inhibits proinflammatory signalling by suppressing the activity of mitogen activated protein kinase (MAP kinase) pathways. MKP-1 is one of the anti-inflammatory genes whose expression is enhanced by glucocorticoids. In the present study, we aimed to investigate the role of MKP-1 in the therapeutic effects of the glucocorticoid dexamethasone in acute allergic reaction. The effects of dexamethasone were studied in wild-type and MKP-1 deficient mice. The mice were first sensitized to ovalbumin, and the allergic reaction was then induced by a subcutaneous ovalbumin injection in the hind paw. Inflammatory edema was quantified with plethysmometer and expression of inflammatory factors was measured by quantitative reverse transcription polymerase chain reaction (RT-PCR). Dexamethasone reduced the ovalbumin-induced paw edema at 1.5, 3 and 6h time points in wild-type mice by 70%, 95% and 89%, respectively. The effect was largely abolished in MKP-1 deficient mice. Furthermore, dexamethasone significantly attenuated the expression of ovalbumin-induced inflammatory factors cyclooxygenase-2 (COX-2); inducible nitric oxide synthase (iNOS); interleukins (IL) 1β, 6 and 13; C-C motif chemokine 11 (CCL-11); tumour necrosis factor (TNF) and thymic stromal lymphopoietin (TSLP) in wild-type mice by more than 40%. In contrast, in MKP-1 deficient mice dexamethasone had no effect or even enhanced the expression of these inflammatory factors. The results suggest that dexamethasone alleviates allergic inflammation through an MKP-1-dependent mechanism. The results also demonstrate MKP-1 as an important conveyor of the favourable glucocorticoid effects in ovalbumin-induced type I allergic reaction. Together with previous findings, the present study supports the concept of MKP-1 enhancing compounds as potential novel anti-inflammatory and anti-allergic drugs.

Signaling and transcriptional dynamics underlying early adaptation to oncogenic BRAF inhibition.

A major contributor to poor sensitivity to anti-cancer kinase inhibitor therapy is drug-induced cellular adaptation, whereby remodeling of signaling and gene regulatory networks permits a drug-tolerant phenotype. Here, we resolve the scale and kinetics of critical subcellular events following oncogenic kinase inhibition and preceding cell cycle re-entry, using mass spectrometry-based phosphoproteomics and RNA sequencing to capture molecular snapshots within the first minutes, hours, and days of BRAF kinase inhibitor exposure in a human BRAF -mutant melanoma model of adaptive therapy resistance. By enriching specific phospho-motifs associated with mitogenic kinase activity, we monitored the dynamics of thousands of growth- and survival-related protein phosphorylation events under oncogenic BRAF inhibition and drug removal. We observed early and sustained inhibition of the BRAF-ERK axis, gradual downregulation of canonical cell cycle-dependent signals, and three distinct and reversible phase transitions toward quiescence. Statistical inference of kinetically-defined signaling and transcriptional modules revealed a concerted response to oncogenic BRAF inhibition and a dominant compensatory induction of SRC family kinase (SFK) signaling, which we found to be at least partially driven by accumulation of reactive oxygen species via impaired redox homeostasis. This induction sensitized cells to co-treatment with an SFK inhibitor across a panel of patient-derived melanoma cell lines and in an orthotopic mouse xenograft model, underscoring the translational potential for measuring the early temporal dynamics of signaling and transcriptional networks under therapeutic challenge.

Knockdown of EIF4G1 in NSCLC induces CXCL8 secretion.

Non-small cell lung cancer (NSCLC) is the most common type of lung tumor; however, we lack effective early detection indicators and therapeutic targets. Eukaryotic translation initiation factor 4 gamma 1 (EIF4G1) is vital to initiate protein synthesis, acting as a scaffolding protein for the eukaryotic protein translation initiation factor complex, EIF4F, which regulates protein synthesis together with EIF4A, EIF4E, and other translation initiation factors. However, EIF4G1's function in NSCLC cancer is unclear. Herein, transcriptome sequencing showed that knockdown of EIF4G1 in H1299 NSCLC cells upregulated the expression of various inflammation-related factors. Inflammatory cytokines were also significantly overexpressed in NSCLC tumor tissues, among which CXCL8 (encoding C-X-C motif chemokine ligand 8) showed the most significant changes in both in the transcriptome sequencing data and tumor tissues. We revealed that EIF4G1 regulates the protein level of TNF receptor superfamily member 10a (TNFRSF10A) resulting in activation of the mitogen activated protein kinase (MAPK) and nuclear factor kappa B (NFκB) pathways, which induces CXCL8 secretion, leading to targeted chemotaxis of immune cells. We verified that H1299 cells with EIF4G1 knockdown showed increased chemotaxis compared with the control group and promoted increased chemotaxis of macrophages. These data suggested that EIF4G1 is an important molecule in the inflammatory response of cancer tissues in NSCLC.