The role of JNK signaling pathway in organ fibrosis.

BACKGROUND: Fibrosis is a tissue damage repair response caused by multiple pathogenic factors which could occur in almost every apparatus and leading to the tissue structure damage, physiological abnormality, and even organ failure until death. Up to now, there is still no specific drugs or strategies can effectively block or changeover tissue fibrosis. JNKs, a subset of mitogen-activated protein kinases (MAPK), have been reported that participates in various biological processes, such as genetic expression, DNA damage, and cell activation/proliferation/death pathways. Increasing studies indicated that abnormal regulation of JNK signal pathway has strongly associated with tissue fibrosis. AIM OF REVIEW: This review designed to sum up the molecular mechanism progresses in the role of JNK signal pathway in organ fibrosis, hoping to provide a novel therapy strategy to tackle tissue fibrosis. KEY SCIENTIFIC CONCEPTS OF REVIEW: Recent evidence shows that JNK signaling pathway could modulates inflammation, immunoreaction, oxidative stress and Multiple cell biological functions in organ fibrosis. Therefore, targeting the JNK pathway may be a useful strategy in cure fibrosis.

Dictyophora indusiata polysaccharide attenuated LPS-induced intestinal inflammation of mice via the TLR4/JNK signaling pathway.

BACKGROUND: Dictyophora indusiata polysaccharide is an important bioactive component of D. indusiata, playing an important role in alleviating inflammation. The present study aimed to investigate the anti-inflammatory effect and mechanism of D. indusiata polysaccharide on lipopolysaccharide (LPS)-induced intestinal inflammation in mice. RESULTS: Our results indicated that D. indusiata polysaccharide ameliorated intestinal inflammation of mice by increasing the body weight, the number of goblet cells and decreasing inflammatory cell infiltration. In addition, D. indusiata polysaccharide significantly up-regulated expression of ZO-1, Occuldin mRNA, which were 2.55-fold and 2.28-fold higher than the LPS group, respectively. In particular, D. indusiata polysaccharide effectively inhibited the Toll-like receptor 4 (TLR4)/ c-Jun NH2-terminal kinase (JNK) signalling pathway which was 0.34-fold and 0.49-fold of gene expression and 0.41-fold and 0.39-fold of protein expression in the LPS group, respectively. CONCLUSION: The results of the present study suggested that D. indusiata polysaccharide exerted anti-inflammatory and intestinal protective effects by inhibiting the TLR4/JNK signaling pathway, which will provide a basis for the potential value of D. indusiata polysaccharide as prebiotics in food applications. © 2024 Society of Chemical Industry.

Qingchang suppository ameliorates mucosal inflammation in ulcerative colitis by inhibiting the differentiation and effector functions of Th1 and Th17 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Qing Chang Suppository (QCS), a traditional Chinese medicine formula, has been shown to effectively alleviate mucosal inflammation in patients with ulcerative colitis (UC). While the mechanism of QCS appears to be related to the regulation of CD4+T cell subset responses, direct evidence demonstrating that QCS inhibits Th1 and Th17 cell activation in UC (particularly based on human data) remains lacking. Additionally, the precise mechanisms through which QCS affects these cells have yet to be fully elucidated. AIM OF STUDY: This study aimed to investigate the effects of QCS on Th1 and Th17 cell responses in UC and to explore the underlying mechanisms. MATERIALS AND METHODS: Twenty-eight patients with mild-to-moderate UC were recruited and treated with QCS for 12 weeks. Symptoms were assessed every two weeks, with sigmoidoscopies performed at baseline and at week 12. Intestinal mucosal biopsies and peripheral blood (PB) were collected at these time points. At the end of the trial, patients were categorized into responder and non-responder groups based on a modified Mayo disease activity index score. Healthy controls (HCs) were defined as subjects without IBD or colorectal carcinoma but with colon polyps. The frequencies of IFN-γ+CD4+T cells and IL-17A+CD4+T cells in PB and colonic mucosa were measured using flow cytometry. The expression levels and localization of T-bet, RORγT, IFN-γ, TNF-α, and IL-17A were determined via immunofluorescence, and JNK signaling activation was assessed through immunoblotting and immunohistochemistry. All parameters were compared across the three groups. RESULTS: At week 12, responders showed a significant reduction in colonic mucosal inflammation compared to baseline, accompanied by decreased frequencies of IFN-γ+CD4+T and IL-17A+CD4+ T cells in both PB and the colonic epithelial layer. Notably, Th1 and Th17 cell activity around intestinal epithelial cells (IECs) was nearly undetectable, as evidenced by the diminished expression of T-bet, RORγT, IFN-γ, TNF-α, and IL-17A. Additionally, JNK phosphorylation in these cells was significantly reduced. In contrast, non-responders exhibited no meaningful improvement; colonic pathology remained unchanged, and elevated levels of IFN-γ+CD4+T and IL-17A+CD 4+T cells persisted in both the PB and colonic epithelial layer. The presence of Th1 and Th17 cells and their associated cytokines around IECs remained substantial, and there was no significant change in JNK activation. CONCLUSION: QCS attenuates mucosal inflammation in UC patients by inhibiting the differentiation and effector functions of Th1 and Th17 cells, primarily through the regulation of the JNK signaling pathway.

JNK Kinase regulates cachexia like syndrome in scribble knockdown tumor model of Drosophila melanogaster.

Cachexia and systemic organ wasting are metabolic syndrome often associated with cancer. However, the exact mechanism of cancer associated cachexia like syndrome still remain elusive. In this study, we utilized a scribble (scrib) knockdown induced hindgut tumor to investigate the role of JNK kinase in cachexia like syndrome. Scrib, a cell polarity regulator, also acts as a tumor suppressor gene. Its loss and mis-localization are reported in various type of malignant cancer-like breast, colon and prostate cancer. The scrib knockdown flies exhibited male lethality, reduced life span, systemic organ wasting and increased pJNK level in hindgut of female flies. Interestingly, knocking down of human JNK Kinase analogue, hep, in scrib knockdown background in hindgut leads to restoration of loss of scrib mediated lethality and systemic organ wasting. Our data showed that scrib loss in hindgut is capable of inducing cancer associated cachexia like syndrome. Here, we firstly report that blocking the JNK signaling pathway effectively rescued the cancer cachexia induced by scrib knockdown, along with its associated gut barrier disruption. These findings have significantly advanced our understanding of cancer cachexia and have potential implications for the development of therapeutic strategies. However, more research is needed to fully understand the complex mechanisms underlying this condition.

Exploring the therapeutic potential of rabdoternin E in lung cancer treatment: Targeting the ROS/p38 MAPK/JNK signaling pathway.

Lung cancer has the highest incidence and mortality rates of all cancer types in China and therefore represents a serious threat to human health. In the present study, the mechanism of rabdoternin E against the proliferation of the lung cancer cell line A549 was explored. It was found that rabdoternin E caused the accumulation of large amounts of reactive oxygen species (ROS), promoted cell S phase arrest by reducing the expression of CDK2 and cyclin A2, induced apoptosis by increasing the Bax/Bcl­2 ratio and promoted the phosphorylation of proteins in the ROS/p38 MAPK/JNK signaling pathway, which is associated with apoptosis and ferroptosis. In addition, it was also found that Z­VAD­FMK (an apoptosis inhibitor), ferrostatin­1 (ferroptosis inhibitor) and N­acetylcysteine (a ROS inhibitor) could partially or greatly reverse the cytotoxicity of rabdoternin E to A549 cells. Similarly, NAC (N­acetylcysteine) treatment notably inhibited the rabdoternin E­stimulated p38 MAPK and JNK activation. Furthermore, in vivo experiments in mice revealed that Rabdoternin E markedly reduced tumor volume and weight and regulated the expression levels of apoptosis and ferroptosis­related proteins (including Ki67, Bcl­2, Bax, glutathione peroxidase 4, solute carrier family 7 member 11 and transferrin) in the tumor tissues of mice. Histopathological observation confirmed that the number of tumor cells decreased markedly after administration of rabdoternin E. Taken together, rabdoternin E induced apoptosis and ferroptosis of A549 cells by activating the ROS/p38 MAPK/JNK signaling pathway. Therefore, the results of the present study showed that rabdoternin E is not toxic to MCF­7 cells (normal lung cells), had no significant effect on body weight and was effective and therefore may be a novel therapeutic treatment for lung cancer.

The JNK and Hippo pathways control epithelial integrity and prevent tumor initiation by regulating an overlapping transcriptome.

Epithelial organs maintain their integrity and prevent tumor initiation by actively removing defective cells, such as those that have lost apicobasal polarity. Here, we identify how transcription factors of two key signaling pathways-Jun-N-terminal kinase (JNK) and Hippo-regulate epithelial integrity by controlling transcription of an overlapping set of target genes. Targeted DamID experiments reveal that, in proliferating cells of the Drosophila melanogaster eye, the AP-1 transcription factor Jun and the Hippo pathway transcription regulators Yorkie and Scalloped bind to a common suite of target genes that promote organ growth. In defective neoplastic cells, AP-1 transcription factors repress transcription of growth genes together with the C-terminal binding protein (CtBP) co-repressor. If gene repression by AP-1/CtBP fails, neoplastic tumor growth ensues, driven by Yorkie/Scalloped. Thus, AP-1/CtBP eliminates defective cells and prevents tumor initiation by acting in parallel to Yorkie/Scalloped to repress expression of a shared transcriptome. These findings shed new light on the maintenance of epithelial integrity and tumor suppression.

Paeoniflorin alleviates DSS-induced ulcerative colitis by suppressing inflammation, oxidative stress, and apoptosis via regulating serum metabolites and inhibiting CDC42/JNK signaling pathway.

Ulcerative colitis (UC) poses a threat to human health. The present study attempts to unravel the efficacy and potential mechanisms of paeoniflorin (PF), a naturally sourced active ingredient, for the management of UC. By establishing a DSS (dextran sulphate sodium)-induced experimental rat model of UC, this study found that PF was effective in ameliorating UC symptoms, inhibiting oxidative stress, inflammation and apoptosis, and repairing colonic epithelial damage. In addition, metabolomics revealed that PF may alleviate UC by primarily improving linoleic acid metabolism. Mechanistically, PF inhibited the CDC42/JNK signaling pathway by targeting CDC42. In particular, HuProtTM20K proteomics, molecular docking and MST revealed that PF is a novel CDC42 inhibitor. In LPS-treated Caco-2 cells, PF similarly inhibited oxidative stress, inflammation, and apoptosis and down-regulated the CDC42/JNK signaling pathway. Overall, PF inhibits oxidative stress, inflammation and apoptosis and repairs colonic epithelial damage through modulation of serum metabolites and inhibition of the CDC42/JNK signaling pathway, leading to alleviation of UC.

Ghrelin Improves Glucolipotoxicity-Induced Pancreatic ß-Cellular Dysfunction and Apoptosis by Inhibiting Endoplasmic Reticulum Stress-Induced IRE1/JNK Pathway.

BACKGROUND: Glucose and fatty acid overload-induced glucolipid toxicity of pancreatic ß-cells is associated with the development of diabetes. Endoplasmic reticulum stress (ERS) plays an essential role in this process. Ghrelin, a peptide secreted by the pancreas, negatively correlates with oxidative stress. The study aimed to investigate ghrelin's role in glycolipid-induced ß-cell dysfunction and its possible mechanism. METHODS: Mouse insulinoma ß-cell, NIT-1 cells, were stimulated with high fat and high glucose to induce glucolipid toxicity. High fat and high glucose-induced NIT-1 cells were treated with acylated ghrelin (AG) or [d-Lys3]-growth hormone releasing peptide (GHRP)-6. Flow cytometry and Cell Counting Kit-8 (CCK-8) assay were performed to assess apoptosis and cell viability. The protein expression related to apoptosis, inositol-requiring kinase 1 (IRE1)/c-Jun N-terminal kinase (JNK) signaling, and ERS were investigated using western blot. Enzyme-linked immunosorbent assay (ELISA) was adopted to examine insulin's synthesis and secretion levels. RESULTS: Ghrelin treatment improved cell viability while inhibiting cell glucolipotoxicity-induced NIT-1 cell apoptosis. Ghrelin can promote the synthesis and secretion of insulin in NIT-1 cells. Mechanistically, ghrelin attenuates ERS and inhibits the IRE1/JNK signaling pathway in NIT-1 cells induced by glucolipotoxicity. CONCLUSION: Ghrelin improves ß-cellular dysfunction induced by glucolipotoxicity by inhibiting the IRE1/JNK pathway induced by ERS. It could be an effective treatment for ß-cellular dysfunction.

Structural basis of homodimerization of the JNK scaffold protein JIP2 and its heterodimerization with JIP1.

The scaffold proteins JIP1 and JIP2 intervene in the c-Jun N-terminal kinase (JNK) pathway to mediate signaling specificity by coordinating the simultaneous assembly of multiple kinases. Using NMR, we demonstrate that JIP1 and JIP2 heterodimerize via their SH3 domains with the affinity of heterodimerization being comparable to homodimerization. We present the high-resolution crystal structure of the JIP2-SH3 homodimer and the JIP1-JIP2-SH3 heterodimeric complex. The JIP2-SH3 structure reveals how charge differences in residues at its dimer interface lead to formation of compensatory hydrogen bonds and salt bridges, distinguishing it from JIP1-SH3. In the JIP1-JIP2-SH3 complex, structural features of each homodimer are employed to stabilize the heterodimer. Building on these insights, we identify key residues crucial for stabilizing the dimer of both JIP1 and JIP2. Through targeted mutations in cellulo, we demonstrate a functional role for the dimerization of the JIP1 and JIP2 scaffold proteins in activation of the JNK signaling pathway.

Therapeutic potential of ASK1 activators in cancer treatment: Current insights and future directions.

Apoptosis signal-regulated kinase 1 (ASK1) is a member of the mitogen-activated protein kinase kinase (MAP3K) family, whose activation and regulation are intricately associated with apoptosis. ASK1 is activated in response to oxidative stress, among other stimuli, subsequently triggering downstream JNK, p38 MAPK, and mitochondria-dependent apoptotic signaling, which participate in the initiation of tumor cell apoptosis induced by various stimuli. Research has shown that ASK1 plays a crucial role in the apoptosis of lung cancer, breast cancer, and liver cancer cells. Currently, the investigation of effective ASK1 activators is a hot topic in research on tumor cell apoptosis. Synthetic compounds such as human ß-defensin, triazolothiazide derivatives and heat shock protein 27 inhibitors; natural compounds such as quercetin, Laminarina japonica polysaccharide-1 peptide and theabrownin; and nanomedicines such as cerium oxide nanoparticles, magnetite FeO nanoparticles and silver nanoparticles can activate ASK1 and induce apoptosis in various tumor cells. This review extensively investigates the roles and activation mechanisms of ASK1, explores its impact on a variety of apoptotic signaling pathways, and discusses the potential therapeutic applications of various ASK1 activators in cancer treatment. In addition, this paper provides an in-depth discussion of the future development of this field and proposes a promising method for further research and clinical progress.

ABT­737 increases cisplatin sensitivity through the ROS­ASK1­JNK MAPK signaling axis in human ovarian cancer cisplatin­resistant A2780/DDP cells.

Ovarian cancer is a gynecological malignant tumor with the highest mortality rate, and chemotherapy resistance seriously affects patient therapeutic outcomes. It has been shown that the high expression of anti­apoptotic proteins Bcl­2 and Bcl­xL is closely related to ovarian cancer chemotherapy resistance. Therefore, reducing Bcl­2 and Bcl­xL expression levels may be essential for reversing drug resistance in ovarian cancer. ABT­737 is a BH3­only protein mimetic, which can effectively inhibit the expression of the anti­apoptotic proteins Bcl­xL and Bcl­2. Although it has been shown that ABT­737 can increase the sensitivity of ovarian cancer cells to cisplatin, the specific molecular mechanism remains unclear and requires further investigation. In the present study, the results revealed that ABT­737 can significantly increase the activation levels of JNK and ASK1 induced by cisplatin in A2780/DDP cells, which are cisplatin­resistant ovarian cancer cells. Inhibition of the JNK and ASK1 pathway could significantly reduce cisplatin cytotoxicity increased by ABT­737 in A2780/DDP cells, while inhibiting the ASK1 pathway could reduce JNK activation. In addition, it was further determined that ABT­737 could increase reactive oxygen species (ROS) levels in A2780/DDP cells induced by cisplatin. Furthermore, the inhibition of ROS could significantly reduce JNK and ASK1 activation and ABT­737­mediated increased cisplatin cytotoxicity in A2780/DDP cells. Overall, the current data identified that activation of the ROS­ASK1­JNK signaling axis plays an essential role in the ability of ABT­737 to increase cisplatin sensitivity in A2780/DDP cells. Therefore, upregulation the ROS­ASK1­JNK signaling axis is a potentially novel molecular mechanism by which ABT­737 can enhance cisplatin sensitivity of ovarian cancer cells. In addition, the present research can also provide new therapeutic strategies and new therapeutic targets for patients with cisplatin­resistant ovarian cancer with high Bcl­2/Bcl­xL expression patterns.

Effect of zearalenone on the jejunum of weaned gilts through the Epac1/Rap1/JNK pathway.

Zearalenone (ZEN) is a nonsteroidal estrogenic mycotoxin produced by Fusarium strains that is harmful to the intestinal health of animals and is widely present in contaminated crops. The objective of this study was to investigate the potential therapeutic target of ZEN-induced jejunal damage in weaned gilts. Sixteen weaned gilts either received a basal diet or a basal diet supplemented with 3.0 mg/kg ZEN in a 32-d experiment. The results showed that ZEN at the concentration of 3.0 mg/kg diet activated the inflammatory response and caused oxidative stress of gilts (P < 0.05). ZEN exposure resulted in the upregulation (P < 0.05) of the Exchange protein directly activated by the cAMP 1/Ras-related protein1/c-Jun N-terminal kinase (Epac1/Rap1/JNK) signaling pathway in the jejunum of gilts in vivo and in the intestinal porcine epithelial cells in vitro. The cell viability, EdU-positive cells, and the mRNA expression of B-cell lymphoma-2 (Bcl-2) were decreased, whereas the reactive oxygen species production and the mRNA expressions of Bcl-2-associated X (Bax) and Cysteine-aspartic acid protease 3 (Caspase3) were increased (P < 0.05) by ZEN. However, ZEN increased the mRNA expression of Bcl-2 and decreased the mRNA expressions of Bax and caspase3 (P < 0.05) after the Epac1 was blocked. These results collectively indicated that a 3.0 mg ZEN /kg diet induced jejunal damage via the Epac1/Rap1/JNK signaling pathway.

Mycotoxins have caused huge economic losses to livestock industry. This study assessed the impact of zearalenone (ZEN) on the jejunum of weaned gilts. Results revealed that significant inflammatory response and oxidative stress were stimulated by 3.0 mg/kg ZEN in the jejunum tissue of weaned gilts. Furthermore, the reactive oxygen species accumulation and apoptosis in the intestinal porcine epithelial cells (IPEC-J2) were triggered, respectively. The negative impact of ZEN on the jejunum was by activation of Epac1/Rap1/JNK signaling pathway in the jejunum and this could be reduced by blocking Epac1. A more comprehensive understanding of the underlying molecular mechanisms will facilitate the development of novel strategies to mitigate the detrimental effect of ZEN on the jejunum of weaned gilts.

Tip60-FOXO regulates JNK signaling mediated apoptosis in Drosophila.

The JNK signaling pathway plays crucial roles in various physiological processes, including cell proliferation, differentiation, migration, apoptosis, and stress response. Dysregulation of this pathway is closely linked to the onset and progression of numerous major diseases, such as developmental defects and tumors. Identifying and characterizing novel components of the JNK signaling pathway to enhance and refine its network hold significant scientific and clinical importance for the prevention and treatment of associated cancers. This study utilized the model organism Drosophila and employed multidisciplinary approaches encompassing genetics, developmental biology, biochemistry, and molecular biology to investigate the interplay between Tip60 and the JNK signaling pathway, and elucidated its regulatory mechanisms. Our findings suggest that loss of Tip60 acetyltransferase activity results in JNK signaling pathway activation and subsequent induction of JNK-dependent apoptosis. Genetic epistasis analysis reveals that Tip60 acts downstream of JNK, paralleling with the transcription factor FOXO. The biochemical results confirm that Tip60 can bind to FOXO and acetylate it. Introduction of human Tip60 into Drosophila effectively mitigates apoptosis induced by JNK signaling activation, underscoring conserved regulatory role of Tip60 in the JNK signaling pathway from Drosophila to humans. This study further enhances our understanding of the regulatory network of the JNK signaling pathway. By revealing the role and mechanism of Tip60 in JNK-dependent apoptosis, it unveils new insights and potential therapeutic avenues for preventing and treating associated cancers.

[Retracted] Matrine inhibits ovarian cancer cell viability and promotes apoptosis by regulating the ERK/JNK signaling pathway via p38MAPK.

Following the publication of the above article, a concerned reader drew to the Editor's attention that certain of the Transwell cell invasion assay data featured in Fig. 1B and C, the immunofluorescence assay data in Fig. 2E and F, the TUNEL assay data in Fig. 4C and the immunohistochemical data in Fig. 4B and E were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes that had either already been published elsewhere prior to the submission of this paper to Oncology Reports, or which under consideration for publication at around the same time. In view of the fact that certain of these data had already apparently been published prior to the submission of this article for publication, the Editor of Oncology Reports has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 45: 82, 2021; DOI: 10.3892/or.2021.8033].

Gp93 inhibits unfolded protein response-mediated c-Jun N-terminal kinase activation and cell invasion.

In eukaryotes, Hsp90B1 serves as a vital chaperonin, facilitating the accurate folding of proteins. Interestingly, Hsp90B1 exhibits contrasting roles in the development of various types of cancers, although the underlying reasons for this duality remain enigmatic. Through the utilization of the Drosophila model, this study unveils the functional significance of Gp93, the Drosophila ortholog of Hsp90B1, which hitherto had limited reported developmental functions. Employing the Drosophila cell invasion model, we elucidated the pivotal role of Gp93 in regulating cell invasion and modulating c-Jun N-terminal kinase (JNK) activation. Furthermore, our investigation highlights the involvement of the unfolded protein response-associated IRE1/XBP1 pathway in governing Gp93 depletion-induced, JNK-dependent cell invasion. Collectively, these findings not only uncover a novel molecular function of Gp93 in Drosophila, but also underscore a significant consideration pertaining to the testing of Hsp90B1 inhibitors in cancer therapy.

JNK signaling and its impact on neural cell maturation and differentiation.

C-Jun-N-terminal-kinases (JNKs), members of the mitogen-activated-protein-kinase family, are significantly linked with neurological and neurodegenerative pathologies and cancer progression. However, JNKs serve key roles under physiological conditions, particularly within the central-nervous-system (CNS), where they are critical in governing neural proliferation and differentiation during both embryogenesis and adult stages. These processes control the development of CNS, avoiding neurodevelopment disorders. JNK are key to maintain the proper activity of neural-stem-cells (NSC) and neural-progenitors (NPC) that exist in adults, which keep the convenient brain plasticity and homeostasis. This review underscores how the interaction of JNK with upstream and downstream molecules acts as a regulatory mechanism to manage the self-renewal capacity and differentiation of NSC/NPC during CNS development and in adult neurogenic niches. Evidence suggests that JNK is reliant on non-canonical Wnt components, Fbw7-ubiquitin-ligase, and WDR62-scaffold-protein, regulating substrates such as transcription factors and cytoskeletal proteins. Therefore, understanding which pathways and molecules interact with JNK will bring knowledge on how JNK activation orchestrates neuronal processes that occur in CNS development and brain disorders.

Fisetin induces G2/M phase arrest and caspase-mediated cleavage of p21Cip1 and p27Kip1 leading to apoptosis and tumor growth inhibition in HNSCC.

The anticancer potential and associated mechanisms of flavonoid fisetin are yet to be fully investigated on human head and neck squamous cell carcinoma (HNSCC). In the present study, fisetin (25-75 µM for 24-48 h) dose-dependently inhibited growth and induced death in HNSCC Cal33 and UM-SCC-22B cells, without showing any death in normal cells. Fisetin (25-50 µM) induced G2/M phase arrest via decrease in Cdc25C, CDK1, cyclin B1 expression, and an increase in p53(S15). A concentration-dependent increase in fisetin-induced DNA damage and apoptosis in HNSCC cells was authenticated by comet assay, gamma-H2A.X(S139) phosphorylation, and marked cleavage of PARP protein. Interestingly, fisetin-induced cell death occurred independently of p53 and reactive oxygen species production. The activation of JNK and inhibition of PI3K/Akt, ERK1/2, EGFR, and STAT-3 signaling were identified. Further, fisetin-induced apoptosis was mediated, in part, via p21Cip1 and p27Kip1 cleavage by caspase, which was reversed by z-VAD-FMK, a pan-caspase inhibitor. Subsequently, fisetin was also found to induce autophagy; nevertheless, autophagy attenuation exaggerated apoptosis. Oral fisetin (50 mg/kg body weight) treatment to establish Cal33 xenograft in mice for 19 days showed 73% inhibition in tumor volume (p < 0.01) along with a decrease in Ki67-positive cells and an increase in cleaved caspase-3 level in tumors. Consistent with the effect of 50 µM fisetin in vitro, the protein levels of p21Cip1 and P27Kip1 were also decreased by fisetin in tumors. Together, these findings showed strong anticancer efficacy of fisetin against HNSCC with downregulation of EGFR-Akt/ERK1/2-STAT-3 pathway and activation of JNK/c-Jun, caspases and caspase-mediated cleavage of p21Cip1 and p27Kip1.

YTE-17 inhibits colonic carcinogenesis by resetting antitumor immune response via Wnt5a/JNK mediated metabolic signaling.

The density and composition of lymphocytes infiltrating colon tumors serve as predictive factors for the clinical outcome of colon cancer. Our previous studies highlighted the potent anti-cancer properties of the principal compounds found in Garcinia yunnanensis (YTE-17), attributing these effects to the regulation of multiple signaling pathways. However, knowledge regarding the mechanism and effect of YTE-17 in the prevention of colorectal cancer is limited. In this study, we conducted isobaric tags for relative and absolute quantification (iTRAQ) analysis on intestinal epithelial cells (IECs) exposed YTE-17, both in vitro and invivo, revealing a significant inhibition of the Wnt family member 5a (Wnt5a)/c-Jun N-terminal kinase (JNK) signaling pathway. Subsequently, we elucidated the influence and mechanism of YTE-17 on the tumor microenvironment (TME), specifically focusing on macrophage-mediated T helper 17 (Th17) cell induction in a colitis-associated cancer (CAC) model with Wnt5a deletion. Additionally, we performed the single-cell RNA sequencing (scRNA-seq) on the colonic tissue from the Wnt5a-deleted CAC model to characterize the composition, lineage, and functional status of immune mesenchymal cells during different stages of colorectal cancer (CRC) progression. Remarkably, our findings demonstrate a significant reduction in M2 macrophage polarization and Th17 cell phenotype upon treatment with YTE-17, leading to the restoration of regulatory T (Treg)/Th17 cell balance in azoxymethane (AOM)/dextran sodium sulfate (DSS) model. Furthermore, we also confirmed that YTE-17 effectively inhibited the glycolysis of Th17 cells in both direct and indirect co-culture systems with M2 macrophages. Notably, our study shed light on potential mechanisms linking the non-canonical Wnt5a/JNK signaling pathway and well-established canonical ß-catenin oncogenic pathway in vivo. Specifically, we proposed that Wnt5a/JNK signaling activity in IECs promotes the development of cancer stem cells with ß-catenin activity within the TME, involving macrophages and T cells. In summary, our study undergoes the potential of YTE-17 as a preventive strategy against CRC development by addressing the imbalance with the immune microenvironment, thereby mitigating the risk of malignancies.