Oroxylin A Directly Targets SRC to Inhibit the PI3K/AKT Signaling Axis in Pancreatic Cancer: An Integrated Bioinformatics and Experimental Study

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with very poor prognosis. Therefore, it is important to fully understand the molecular mechanism underlying its occurrence and development. Pumilio RNA-binding family member 1 (PUM1) has been reported to function as an oncogene in ovarian cancer and nonsmall cell lung cancer. However, its role and mechanism in PDAC have not been fully illuminated. Here, we found that the PUM1 protein levels were higher in PDAC tissues than in adjacent tissues and that PUM1 levels were significantly associated with TNM stage and overall survival time, indicating a correlation between high PUM1 expression and poor prognosis in patients with PDAC. In vitro and in vivo assays showed that PUM1 knockdown inhibited cell proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT), and promoted apoptosis in MIA PaCa-2 and PANC-1 cells. Through cDNA microarrays and ingenuity pathway analysis, we found that the activation of the eIF2 signaling pathway significantly correlated with PUM1 knockdown. These results were further confirmed by the increased levels of key components of the eIF2 signaling pathway, p-PERK, p-EIF2A, and ATF4 in PUM1 knockdown cells. We also found that PUM1 levels have a significant negative correlation with p-PERK levels in PDAC tissues and that PERK overexpression inhibited cell proliferation, migration, invasion, and EMT, and promoted apoptosis in vitro. Moreover, a PERK inhibitor alleviated the effects of PUM1 knockdown on cell proliferation, apoptosis, migration, invasion, and EMT. Taken together, our results revealed that PUM1 knockdown suppressed cell growth, invasion, and metastasis, and promoted apoptosis by activating the PERK/eIF2/ATF4 signaling pathway in PDAC cells. PUM1 could be a potential target to develop pharmaceuticals and novel therapeutic strategies for the treatment of PDAC.

Desmoplasia of Pancreatic Ductal Adenocarcinoma

Flavonoids exhibit anti-tumor properties against many human cancer cells, indicating their potential as effective anticancer medicines. Oroxylin A (OrA) is a monoflavonoid molecule that shows significant promise against several types of cancer and possesses a substantial anticancer impact while causing minimal harm to normal tissue. Limited studies have provided a systematic review deciphering the role of oroxylin A in combating breast carcinoma. Hence, we thoroughly analyzed existing research to report various mechanism by which OrA impedes tumor advancement in breast carcinoma, including autophagy, cell cycle arrest, angiogenesis suppression, apoptosis, and glycolysis inhibition. We collected several significant research related to the anticancer potential of oroxylin A and demonstrated anticancerous potential of OrA and its specific mode of action in several human carcinomas. Additionally, we have also incorporated several studies to decipher the structure, bioavailability, and anti-breast cancer potential of Oroxylin A in breast cancer. Overall, this review supports the potential of oroxylin A for developing better anti breast cancer therapeutic approach.

Intratumoral microbiota are essential components of tumours and are substantially involved in tumour initiation, progression, and treatment. However, owing to the vast diversity and abundance of microbial species, understanding their molecular mechanisms within tumours, particularly in pancreatic cancer (PC), remains challenging. Microbiota composition was analysed in pancreatic cystic neoplasm (PCN) and pancreatic ductal adenocarcinoma (PDAC) tissues using 16S rRNA sequencing. Liquid chromatography-mass spectrometry (LC-MS) was employed in the same samples to quantify tissue metabolites. Subsequently, the association between intratumoral microbiota and metabolites was examined to investigate potential interactions. Western blotting, quantitative real-time polymerase chain reaction, and immunohistochemistry were used to detect the expression of 3-hydroxyacyl-CoA dehydrogenase (HADH), AMP-activated protein kinase (AMPK), and G protein-coupled receptor 43 (GPR43). The biological role of the intratumoral bacterial metabolite sodium acetate (NaAc) was determined through in vitro and in vivo experiments. Certain bacterial taxa, including Muribaculaceae, Prevotella, Lachnospiraceae NK4A136 group, and Blautia, were significantly enriched in PDAC tissues and were associated with lipid molecules. Specific taxa exhibited positive correlations with lipid molecules in PDAC tissues. Low concentrations of NaAc promoted PC cell proliferation and migration in vitro and enhanced tumour growth in vivo. Mechanistically, NaAc activated the GPR43/AMPK/HADH signalling pathway in PC cells, leading to increased fatty acid oxidation. Specific intratumoral microbiota contribute to the progression from PCN and PDAC by modulating lipid metabolism. These findings provide a theoretical framework for understanding the microbiota-driven mechanisms in PDAC and highlight their role in tumour growth.

AML1/ETO fusion gene is one of disease-causing genes of t(8;21)-positive acute myeloid leukemia (AML). Oroxylin A (OA) has showed anticancer effects on other cancer cells. Here, studies were conducted to determine the antileukemia effect of OA on t(8;21)-positive AML cells in vitro and in vivo. The effects of OA on cell viability of t(8;21)-positive Kasumi-1 and primary AML cells were analyzed by MTT assay. Cell differentiation was examined by NBT reduction assay, flow cytometry analysis for CD11b/CD14, and Giemsa stain. Protein expressions were determined by Western blots. Immunofluorescence assay was used to verify the effect of OA on HDAC-1 expression in vivo. Immunohistochemical staining was applied to evaluate leukemic infiltration of AML-bearing NOD/SCID mice. OA enhanced NBT reduction activity and CD11b/CD14 expression of AML1/ETO-positive AML cells markedly. Results of Giemsa staining also demonstrated that OA could induce the morphologic changes with reduction of nuclear/cytoplasmic ratios, suggesting the cell differentiation induced by OA. Further study showed that OA decreased the expression of fusion protein AML1/ETO and down-regulated HDAC-1 protein levels in vitro and in vivo. Moreover, OA increased the expression of differentiation-related proteins C/EBPα and P21. Acetylation levels of histones were also advanced obviously after treatment of OA. In vivo study indicated that OA could prolong the survival of AML-bearing NOD/SCID mice and reduce leukocytic infiltration of the spleen. All these results suggested that OA might be a novel candidate agent for differentiation therapy for AML1/ETO-positive AML and the mechanism required further investigation.

Therapeutic efficacy of l-ornithine- l-aspartate infusions in patients with cirrhosis and hepatic encephalopathy: Results of a placebo-controlled, double-blind study : Kircheis, G., Nilius, R., Held, C., Berndt, H., Buchner, M., Gortelmeyer, R., Hendricks, R., Kruger, B., Kuklinski, B., Meister, H., Otto, H.-J., Rink, C., Rosch, W., Stauch, S. Merz Clinical Research Department, Eckenheimer Landstrasse 100-104, 60318 Frankfurt/Main, Germany Hepatol 1997;

Therapeutic potential of Oroxylin A in rheumatoid arthritis

Hepatic stellate cell (HSC) activation plays an indispensable role in hepatic fibrosis. Inducing apoptosis of activated HSCs can attenuate or reverse fibrogenesis. In this study, we initially found that oroxylin A (OA) protected CCl4-induced liver injury accompanied by endoplasmic reticulum stress (ERS) activation of HSCs in mice. In vitro, OA treatment markedly reduced fibrogenesis by modulating extracellular matrix synthesis and degradation. OA inhibited cell proliferation and induced cell cycle arrest of HSCs at S phase. Further, OA was observed to induce HSC apoptosis, as indicated by caspase activation. Using the eIF2α dephosphorylation inhibitor salubrinal, we found that ERS pathway activation was required for OA to induce HSC apoptosis. ERS-related proteins were significantly upregulated by OA treatment, and salubrinal abrogated the effects of OA on HSCs. Thus, we inferred that OA attenuated HSC activation by promoting ERS. In vivo, inhibition of ERS by salubrinal partly abrogated the hepatoprotective effect of OA in CCl4-treated mice. In conclusion, our findings suggest a role for ERS in the mechanism underlying amelioration of hepatic fibrosis by OA.

S100P-Binding Protein, S100PBP, Mediates Adhesion through Regulation of Cathepsin Z in Pancreatic Cancer Cells

Simple SummaryOncogenic KrasG12D and tumor inflammation are critical components of the development and dissemination of pancreatic ductal adenocarcinoma (PDAC). The aim of this study is to investigate a lesser-known cytokine, CCL15, that functions as a new downstream target of KrasG12D with the purpose of regulating PDAC cell migration and invasion. We showed increased levels of CCL15 as well as the presence of its receptors, including CCR1 and CCR3, in PDAC tissues and cell lines. The knockdown of CCL15 diminished metastatic Panc-1 cell migration, whereas the treatment of CCL15 in non-metastatic BxPC-3 cells promoted BxPC-3 cell motility. Similar results were verified using murine metastatic PDAC KP-2 cells. Furthermore, we demonstrated that CCL15-modulated PDAC cell migration through the upregulation of cellular reactive oxygen species (ROS) levels and the knockdown of KrasG12D resulted in a decrease in CCL15. Altogether, our data unveiled a new mechanism of oncogenic KrasG12D in modulating PDAC inflammation and spreading.Pancreatic ductal adenocarcinoma (PDAC) is well known for its high death rate due to prompt cancer metastasis caused by cancer cell migration and invasion within the early stages of its development. Here, we reveal a new function of cytokine CCL15, namely the upregulation of PDAC cell migration and invasion. We showed increased levels of CCL15 transcripts and protein expressions in human PDAC tissue samples, as well as in cultured cell lines. Furthermore, PDAC cells also expressed CCL15 receptors, including CCR1 and CCR3. Murine PDAC cell lines and tissues strengthened this finding. The manipulation of CCL15 in metastatic Panc-1 cells through CCL15 knockdown or CCL15 neutralization decreased Panc-1 cell motility and invasiveness. In addition, treating non-metastatic BxPC-3 cells with recombinant CCL15 accelerated the cell migration of BxPC-3. A reduction in the levels of reactive oxygen species (ROS) by either N-Acetyl-L-Cysteine treatment or p22phox knockdown led to a decrease in Panc-1 cell migration and a reversed effect on recombinant CCL15-promoted BxPC-3 cell movement. Importantly, the knockdown of oncogenic Kras in Panc-1 cells abolished CCL15 protein expression and impeded cell migration without affecting PDAC cell growth. Altogether, our work elucidates an additional molecular pathway of oncogenic Kras to promote PDAC metastasis through the upregulation of cell migration and invasion by the Kras downstream CCL15, a lesser-known cytokine within the cancer research field.

ObjectiveT-cell lymphoma invasion and metastasis inducing factor 1 (Tiam1) is known to be involved in tumor progression. However, its molecular roles and mechanism in pancreatic ductal adenocarcinoma (PDAC) remain unclear. The purpose of this study is to determine Tiam1 expression levels and investigate its underlying molecular mechanism in PDAC.Materials and methodsTiam1 protein expression levels in PDAC tissues were examined using immunohistochemistry. Tiam1 expression was confirmed in pancreatic cancer (PC) cells by Western blot and immunofluorescence staining. Tiam1-silenced PC cells were created using short interfering RNA. Subsequently, colony formation, scratch, and migration and invasion assays were carried out to explore the molecular mechanisms of Tiam1 in PC cells.ResultsThe results indicated that Tiam1 expression was significantly higher in PDAC tissues than in paired non-tumor tissues, and overexpression of Tiam1 was significantly correlated with histological grade (P=0.040) and lymph node metastasis (P=0.031) in PDAC. The PDAC patients with high Tiam1 expression had significantly lower 5-year overall survival than patients with low Tiam1 expression. More importantly, univariate and multivariate analysis suggested that Tiam1 expression, along with lymph node metastasis, is a significant independent prognostic factor for patients with PDAC. Furthermore, we also demonstrated that the downregulation of Tiam1 was associated with decreased cell proliferation and reduced migratory and invasive capability.ConclusionHigh expression of Tiam1 plays a significant role in the progression of PDAC and may be a potential biomarker of poor prognosis as well as a therapeutic target.

Steroid hormone receptors (SRs) drive progression of hormone-dependent cancers (e.g. breast and prostate) where they are targeted by lifesaving treatments designed to block SR actions. In pancreatic ductal adenocarcinoma (PDA), glucocorticoid receptor (GR) and progesterone receptor (PR) are mediators of tumor progression, micropinocytosis, and immune evasion. Furthermore, PDA is associated with increased expression of both GR and PR. PDA is a particularly lethal disease with a 5-year survival around 11%, frequently late-stage diagnosis, and poor treatment options. Despite this, SR mechanisms in PDA remain unexplored. We hypothesize that SRs (namely GR and PR) contribute to PDA progression, and that ligand-binding, post-translational modifications, and selected coregulators modulate SR actions in the context of stress-activated signaling pathways associated with aggressive PDA phenotypes. Here, we present a study of SRs in PDA cell culture with a focus on SR expression, oncogenic signaling, and SR-mediated advanced cancer phenotypes. Herein, we characterized cellular migration via transwell migration assay, mRNA expression via qPCR, and protein expression via western blot. We first defined variable SR expression levels in a panel of human immortalized PDA cell models (Aspc-1, Bxpc-3, Capan-1, CFPAC, HPAF-II, Hs 766T, MIA Paca-2, Panc-1, Panc 10.05). We next performed studies focused on SR phosphorylation in response to steroids and cytokines as well as interplay between SRs and signaling pathways including p38 MAP Kinase (MAPK), AKT, and RAS pathways. Finally, we measured cell migration in response to treatment with SR ligands, SR inhibitors, and cytokines, including TGFbeta, IL-1beta, and Leukemia Inhibitory Factory, all of which are prevalent in the PDA tumor microenvironment and known to promote PDA progression. We observed that glucocorticoid or cytokine treatments induced increased migration of Panc-1, MIA Paca-2, CFPAC, and Panc 10.05 cells relative to vehicle-treated controls. Treatment with SR antagonists (mifepristone, relacorilant) attenuated cytokine- and serum-induced migration. In response to either ligand or cytokine treatment, PDA cell lines exhibited phosphorylation of GR at Ser134, a stress-induced p38 MAPK consensus phosphorylation site that drives advanced phenotypes in triple negative breast cancer models. Phosphorylation of GR Ser134 is mediated by components from oncogenic signaling cascades such as p38 MAPK and AKT. Finally, we have determined that GR and KRAS interact via coimmunoprecipitation in PDAC cell line CFPAC. This study provides preliminary analyses of SR expression in PDA models and SR integration stress-activated signaling pathways linked to aggressive PDA biology. Future studies will include invasion and sphere-forming assays, rigorous interrogation of stress-activated signaling pathways, SR-KRAS and SR-SR interactions, and transcriptional studies that define SR-dependent gene signatures in PDA. Our long term goal is to elucidate novel paths to improved PDA screening and treatment. Citation Format: Oliver M. Stockert, Carol A. Lange. Steroid receptors modulate oncogenic signaling and drive cell migration in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research—Emerging Science Driving Transformative Solutions; Boston, MA; 2025 Sep 28-Oct 1; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl_3):Abstract nr A053.

Bone morphogenetic protein receptor 2 (BMPR2) is an important transmembrane serine/threonine kinase that involves oncogenic processes in multiple cancers. However, the role of BMPR2 and its regulatory mechanism in pancreatic ductal adenocarcinoma (PDAC) remain unknown. We performed a tissue array to explore the expression of BMPR2 in PDAC tissues. The Cell Counting Kit-8 (CCK-8) and colony formation assays were used to measure PDAC cells' proliferation. Proteomics and mass spectrometry technology was applied to analyze the BMPR2-regulating proteins. Flow cytometry was used to analyze the cell cycle distribution of PDAC cells. Orthotopic pancreatic cancer (PC) and patient-derived xenograft (PDX) models were used for in vivo experiments. This study revealed the over-expression of BMPR2 in PDAC tissues and its proliferation-promoting role in PDAC cells. By carrying out protein mass spectrometry technique as well as bioinformatics analysis, we identified that BMPR2 regulated the growth factor receptor-bound protein 2/phosphatidylinositol 3-kinase/protein kinase B (GRB2/PI3K/AKT) signaling pathway, and further in vitro experiments showed that inhibition of BMPR2 resulted in suppressing proliferation and G2/M arrest by inhibiting the GRB2/PI3K/AKT signaling pathway in PDAC cells. The inhibition of BMPR2 by LDN193189 showed similar results in PDAC cells, orthotopic PC, and PDX models, which revealed that inhibition of BMPR2 significantly suppressed tumor growth by suppressing the GRB2/PI3K/AKT axis. Inhibition of BMPR2 suppresses PDAC growth by regulating the GRB2/PI3K/AKT axis and is a promising PDAC treatment strategy.

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis. Dysregulated cholesterol metabolism contributes to tumor progression, but its regulatory mechanisms in PDAC are unclear. This study explored the role and mechanism of homeobox C9 (HOXC9) in cholesterol regulation and PDAC development. HOXC9 was identified by bioinformatics as a key cholesterol metabolism gene in PDAC. Its expression was validated via qRT-PCR, Western blot, and immunohistochemistry, while cholesterol were measured using microassay and Filipin III staining. In vitro assays and subcutaneous tumor models in nude mice were used to assess its functional roles. RNA-seq, ChIP-qPCR, and dual-luciferase reporter assays explored molecular mechanisms. HOXC9 was identified as a key cholesterol metabolism-related transcription factor in PDAC. High-throughput data analysis based on TCGA databases further revealed that HOXC9 was highly expressed in PDAC tissues and associated with dismal prognosis. Clinically, HOXC9 upregulation correlates positively with tumor cholesterol, advanced stage, and reduced survival. Functionally, HOXC9 promotes PDAC cell proliferation, migration, and invasion in a cholesterol-dependent manner. In vivo, HOXC9 knockdown suppressed tumor growth and intratumoral cholesterol in nude mice, an effect reversible by high-cholesterol diet. Mechanistically, transcriptome sequencing highlighted the PI3K-Akt pathway as a key downstream target. HOXC9 transcriptionally activates ITGA10, which upregulates HMGCR via the FAK/PI3K/CREB, thereby driving cholesterol metabolism and tumor progression. HOXC9 may be a key transcriptional regulator of cholesterol metabolism in PDAC, promoting malignant progression by activating the ITGA10/FAK/PI3K/CREB to regulate HMGCR-mediated cholesterol synthesis. The essential role of the HOXC9-ITGA10-cholesterol axis in PDAC progression offers a novel potential target for therapy.

686P - Early detection of pancreatic ductal adenocarcinoma using methylation signatures in circulating tumour DNA