Mouse Colon Cancer Research Articles

Antagonistic roles of cGAS/STING signaling in colorectal cancer chemotherapy.

FOLFOX, composed of 5-FU, oxaliplatin and leucovorin, is a first line chemotherapy regimen for colorectal cancer (CRC) treatment. In this study, we show that 5-FU and oxaliplatin induce DNA damage and activate cGAS/STING signaling leading to enhanced expression of interferon (IFN) β, IFN-stimulated genes and inflammatory cytokines in mouse and human colon cancer cells as well as increased intratumoral CD8+ T cells in mice. Crucially, 5-FU and oxaliplatin increase PD-L1 expression at the mRNA and protein levels, which has been shown to inhibit CD8+ T cell function. Depletion of cGAS, STING, IRF3, or IFNα/β receptor 1 (IFNAR1) abolishes this increase, indicating that 5-FU/oxaliplatin mediated upregulation of PD-L1 expression is dependent on tumor cell intrinsic cGAS/STING signaling. These results imply opposing roles for FOLFOX during cancer treatment. On one hand, 5-FU and oxaliplatin activate the innate immune response to facilitate anti-tumor immunity, and conversely upregulate PD-L1 expression to evade immune surveillance. Analysis of TCGA colon cancer dataset shows a positive correlation between expression of PD-L1 and components of the cGAS/STING pathway, supporting a role for cGAS/STING signaling in upregulating PD-L1 expression in colon cancer patients. Tumor studies in syngeneic immune competent mice demonstrate that the combination of 5-FU/oxaliplatin and anti-PD-1 significantly reduced tumor growth of colon cancer cells compared to 5-FU/oxaliplatin treatment alone. Taken together, our studies have identified a unique pathway leading to chemoresistance and provide a rationale to combine FOLFOX with anti-PD-1/PD-L1 as an effective CRC treatment.

Synthesis, pharmacological evaluation, and modeling of novel quaternary ammonium salts derived from β-carboline containing an imidazole moiety as angiogenesis inhibitors

In this study, a series of novel β-carboline condensed imidazolium derivatives (7a-7y) were designed and synthesized by incorporating imidazolium salt structures into β-carboline. The cytotoxicity of compounds 7a-7y was evaluated in various cancer cell lines, including lung cancer (A549), gastric cancer (BGC-823), mouse colon cancer (CT-26), liver cancer (Bel-7402), and breast cancer (MCF-7), using the MTT assay. Most compounds exhibited significant activity against one or more of the cancer cell lines. Notably, compounds 7 g, 7o, 7r, 7 s, 7u, 7v, 7x, and 7w showed the highest cytotoxic activity (IC50 < 2 μM) in the tested tumor cell lines. Compound 7x demonstrated cytotoxic activities of 1.3 ± 0.3 μM (for BGC-823), 2.4 ± 0.4 μM (against A549), 7.8 ± 0.9 μM (for Bel-7402), and 9.8 ± 1.4 μM (against CT-26). The chick chorioallantoic membrane assay revealed significant anti-angiogenic potential of compound 7x. Molecular imprinting studies suggested the anti-angiogenic effect of compound 7x might be attributed to inhibition of VEGFR2 kinase. Molecular docking and molecular dynamics further indicate that its activity may be primarily associated with the potential inhibition of VEGFR2. Our research outcomes have provided valuable lead compounds for the development of novel antitumor drugs and have offered beneficial insights for subsequent drug design and optimization.

Yes-associated protein indispensably mediates hirsutine-induced inhibition on cell growth and Wnt/β-catenin signaling in colorectal cancer

Background and purpose: Targeting Wnt/β-catenin signaling emerges as one of the promising strategies for colorectal cancer (CRC) treatment, as this signaling is highly activated in CRC progression. Despite reports on the cytotoxic effects of hirsutine (HT), an indole alkaloid found in herbal medicines from the genus Uncaria, its therapeutic potential for CRC and the involved mechanisms are poorly understood. This study investigates the anticancer efficacy and the probable mechanisms of HT against CRC. Methods: To evaluate in vitro anticancer activity of HT, cell growth examined by MTT and colony formation assay, and apoptosis examined by flow cytometry were performed. To explore the mechanisms, RNA-sequencing, western blotting, dual-luciferase reporter assays, immunofluorescence, and co-immunoprecipitation were performed. Mouse model of azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colon cancer was utilized to assess HT's in vivo anticancer efficacy. Results: HT significantly inhibited CRC cell proliferation with IC50 values of 22.25 ± 3.27 μM for SW620 cells and 22.24 ± 2.36 μM for HCT116 cells, and induced apoptosis. HT decreased protein levels of Wnt3a and β-catenin dose- and time-dependently, and inhibited TOP/FOP FLASH reporter activity, nuclear travel of β-catenin, and downstream targets like c-Myc, Cyclin D1, VEGF. HT reduced β-catenin protein half-life, and the reversal of this effect by MG132 indicated that HT facilitated proteasome-dependent degradation of β-catenin in these two cell lines. HT also increased β-catenin ubiquitination without affecting Axin and β-TrCP levels. HT treatment for 24 h induced YAP cytoplasmic retention, enhanced YAP interacting with β-catenin and β-TrCP, triggering destruction complex formation and β-catenin ubiquitination and degradation, while YAP siRNA impaired these effects. Additionally, β-catenin overexpression and LiCl treatment counteracted HT-induced inhibition on cell growth and Wnt/β-catenin cascade. In model of AOM/DSS-induced mouse colon cancer, compared with AOM/DSS treatment group, HT recovered colon length, reduced tumor numbers and radius, and downregulated β-catenin and Ki-67, while upregulated cleaved PARP in the colorectal tissue with tumors. Conclusion: HT exhibits anticancer activity against CRC probably by inhibiting Wnt/β-catenin signaling, with YAP playing an indispensible role during the process, highlighting HT as a potential novel candidate drug for CRC therapy.

Synthesis, comprehensive characterization and investigation of biological properties of newly synthesized Pt(II)-aminothiazole complexes: Combining experimental and computational approach

The synthesis of new platinum(II) complexes with 2-amino-6-methyl-benzothiazole and 2-amino-6-chlorobenzothiazole as ligands were reported and the proposed structure of the complexes were determined using elemental microanalysis, infrared, 1H and 13C NMR spectroscopy. To verify the suggested structures a computational approach utilizing Density Functional Theory was implemented. The results showed a strong correlation with experimental data, confirming the hypothesized structures of investigated compounds.The interactions of novel platinum(II) complexes with human serum albumin and calf thymus DNA were studied by fluorescence spectroscopy and UV-Vis absorption. The predominantly elevated values of the binding constant, Kb, and the Stern-Volmer quenching constant, KSV, stem from the effective attachment of complexes to both HSA and CT-DNA. To establish the mode of interaction, viscosity measurements were conducted. The results showed that complexes are not performing intercalation between the DNA bases, and which probably bind to minor/major grooves.In vitro cytotoxic effect of ligands and platinum(II) complexes was evaluated in the panel of cancer cell lines (mouse mammary carcinoma and colon cancer, and on human mammary carcinoma and colon cancer), and on non-tumor cells, mouse mesenchymal stem cell line using MTT assay. Platinum(II) complex with 2-amino-6-methyl-benzothiazole showed a very good cytotoxic activity mainly by inducing apoptosis.In vitro antimicrobial assay of ligands and complexes was tested against 11 microorganisms using microdilution method and the minimum inhibitory concentration and minimum microbicidal concentration were identified. All tested compounds exhibited moderate antifungal activity and significantly better action on S. aureus ATCC 25923.

Alleviating tumor hypoxia and immunosuppression via sononeoperfusion: A new Ally for potentiating anti-PD-L1 blockade of solid tumor

The hypoxic and immunosuppressive tumor microenvironment (TME) remains a major obstacle to impede cancer immunotherapy. Here, we found that sononeoperfusion—a new effect of tumor perfusion enhancement induced by low mechanical index ultrasound stimulated microbubble cavitation (USMC)—ameliorated tumor tissue oxygenation and induced tumor vascular normalization (TVN). This TVN might be associated with the down-regulation of hypoxia-inducible factor 1-alpha (HIF-1α) and vascular endothelial growth factor (VEGF) within tumors. Moreover, the sononeoperfusion effect reduced the accumulation of immunosuppressive cells, such as regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs) and M2-like tumor-associated macrophages (M2-TAMs), and decreased the production of immune inhibitory factors like transforming growth factor-β1 (TGF-β1), interleukin 10 (IL-10), chemoattractant chemokines CC-chemokine ligand 22 (CCL22), CCL28, adenosine and lactate within tumors. Notably, flow cytometry analysis revealed that sononeoperfusion not only increased the percentage of tumor infiltrating-CD8+ T cells, but also promoted the generation of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) by these cells. Furthermore, the improved immune TME by sononeoperfusion effect sensitized anti-PD-L1 treatment both in MC38 colon cancer and Lewis lung carcinoma mice, resulting in tumor regression and prolonged survival. Mechanically, the enhanced efficacy of combination therapy was mainly based on promoting the infiltration and function of CD8+ T cells within tumors. Together, sononeoperfusion could ameliorate hypoxia and immunosuppression in the TME, thereby potentiating anti-PD-L1 therapy for solid tumors. This novel method of USMC generating sononeoperfusion effect may provide a new therapeutic modality for facilitating cancer immunotherapy.

Antioxidative and Apoptotic Activities of Vernonia amygdalina Ethanolic Extract in the AOM/DSS Mice Model of Colon Cancer

This study examined the efficacy and safety of Vernonia amygdalina ethanol extract (VAEE) therapy in treating azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colon cancer in mice, aiming to uncover the underlying mechanisms. A colon cancer mice model was used to evaluate the effects of VAEE on antioxidant enzyme levels and apoptosis. VAEE treatment increased SOD and caspase-3 levels while reducing MDA and Bcl-2 levels. These results indicate the potential of VAEE as an anticancer agent, with several doses showing significant increases in SOD and caspase-3 levels while significantly reducing MDA and Bcl-2 levels compared to the negative control (p&lt;0.05). A dose of 500 mg/kg BW appears to be a potential candidate anticancer agent. Further studies on the molecular mechanisms and long-term effects are needed to support clinical applications. Keywords: Antioxidants, AOM/DSS, Apoptosis, VAEE, Colon Cancer

Cuproptosis in microsatellite stable colon cancer cells affects the cytotoxicity of CD8+T through the WNT signaling pathway

The microsatellite stable (MSS) colon cancer (CC) has long been considered resistant to immunotherapy. Cuproptosis, as a novel form of cell death, may interact with tumor immunity. This project focused on the impact of cuproptosis on the cytotoxicity of CD8+T in MSS CC, aiming to provide effective clues for improving the treatment strategy of MSS CC. The study developed an MSS CC cuproptosis model using 50 nM elesclomol and 1 μM CuCl2. Cuproptotic SW480 cells were directly co-cultured with CD8+ T cells. Cuproptosis levels were assessed via intracellular copper ion detection, Western blot, and confocal laser scanning microscopy. CCK-8, Hochest/PI staining, CFSE cell proliferation assay, LDH cytotoxicity detection, and ELISA were used to evaluate CD8+ T cell immune activity and cytotoxicity. Transcriptome sequencing and bioinformatics analysis identified regulated signals in cuproptotic SW480 cells. A rescue experiment utilized a WNT pathway activator (BML-284). PD-L1 expression in cells/membranes was analyzed using qRT-PCR, Western blot, and flow cytometry. NSG mice were immunoreconstituted, and the effects of cuproptosis on immune infiltration and cancer progression in MSS CC mice were assessed using ELISA and immunohistochemistry (IHC). Treatment with 50 nM elesclomol and 1 μM CuCl2 significantly increased cuproptosis in SW480 cells. Co-culture with CD8+ T cells enhanced their cytotoxicity. Sequencing revealed cuproptosis-mediated modulation of immune and inflammatory pathways, including WNT signaling. Rescue experiments showed downregulation of WNT signaling in cuproptotic SW480 cells. Indirectly, CD8+ T cell immune function was enhanced by reducing PD-L1 expression. In mice, cuproptosis resulted in increased infiltration of CD8+ T cells in tumor tissue, leading to delayed cancer progression compared to the control group. Cuproptosis in MSS CC cells enhances the cytotoxicity of CD8+ T cells, which may be achieved through downregulation of the WNT signaling pathway and decreased expression of PD-L1. In the future, drugs that can induce cuproptosis may be a promising approach to improve MSS CC immunotherapy.

Research on curcumin mediating immunotherapy of colorectal cancer by regulating cancer associated fibroblasts.

The objective was to investigate curcumin's (Cur) function and associated molecular mechanisms in regulating tumor immunity in colon cancer. Primary cancer-associated fibroblasts (CAFs) from mouse CT26 colon cancer tumors were isolated. Validation of primary CAFs using immunofluorescence assay was done. Cell Counting Kit-8 experiments, real-time quantitative PCR (qPCR), and enzyme linked immunosorbent assay experiments were conducted to investigate how curcumin affected the growth and cytokine secretion functions of CAFs. The effect of curcumin on regulating PD-L1 expression on CT26 cells through CAFs in vitro was explored through coculture of CAFs and tumor cells, qPCR, and western blot experiments. A mouse colon cancer cell model was established in Balb/c nude mice to explore the effect of curcumin on colon tumor cells. Changes in the tumor microenvironment were detected by flow cytometry to explore the synergistic effect of curcumin combined with anti-PD-1 monoclonal antibody in the treatment of mouse colon cancer. In vitro, curcumin prevented the growth and TGF-β secretion of CT26 cells. At the same time, curcumin inhibited the secretion of TGF-β by CAFs, thereby downregulating the PD-L1 expression of CT26 cells. In vivo, curcumin combined with anti-PD-1 antibodies can further enhance the inhibitory effect of PD-1 antibodies on tumors and increase the number of tumor-suppressing immune cells in the tumor microenvironment, such as M1 macrophages and CD8 T cells, thus inhibiting tumors. Immune M2 macrophages, regulatory T cells, and other cells were reduced. In conclusion, curcumin reduces the expression of PD-L1 in colon cancer cells and improves the tumor immune microenvironment by inhibiting the proliferation of CAFs and the secretion of TGF-β. Curcumin and anti-PD-1 treatment have synergistic inhibitory effects on colon cancer.

IL-1β mediates Candida tropicalis-induced immunosuppressive function of MDSCs to foster colorectal cancer

BackgroundThere is increasing evidence that gut fungi dysbiosis plays a crucial role in the development and progression of colorectal cancer (CRC). It has been reported that gut fungi exacerbate the severity of CRC by regulating tumor immunity. Our previous studies have shown that the opportunistic pathogenic fungal pathogen, Candida tropicalis (C. tropicalis) promotes CRC progression by enhancing the immunosuppressive function of MDSCs and activating the NLRP3 inflammasome of MDSCs. However, the relationship between IL-1β produced by NLRP3 inflammasome activation and the immunosuppressive function of MDSCs enhanced by C. tropicalis in CRC remains unclear.MethodsThe TCGA database was used to analyze the relationship between IL-1β and genes related to immunosuppressive function of MDSCs in human CRC. The expression of IL-1β in human CRC tissues was detected by immunofluorescence staining. The proteomic analysis was performed on the culture supernatant of C. tropicalis-stimulated MDSCs. The experiments of supplementing and blocking IL-1β as well as inhibiting the NLRP3 inflammasome activation were conducted. A mouse colon cancer xenograft model was established by using MC38 colon cancer cell line.ResultsAnalysis of CRC clinical samples showed that the high expression of IL-1β was closely related to the immunosuppressive function of tumor-infiltrated MDSCs. The results of in vitro experiments revealed that IL-1β was the most secreted cytokine of MDSCs stimulated by C. tropicalis. In vitro supplementation of IL-1β further enhanced the immunosuppressive function of C. tropicalis-stimulated MDSCs and NLRP3-IL-1β axis mediated the immunosuppressive function of MDSCs enhanced by C. tropicalis. Finally, blockade of IL-1β secreted by MDSCs augmented antitumor immunity and mitigated C. tropicalis-associated colon cancer.ConclusionsC. tropicalis promotes excessive secretion of IL-1β from MDSCs via the NLRP3 inflammasome. IL-1β further enhances the immunosuppressive function of MDSCs to inhibit antitumor immunity, thus promoting the progression of CRC. Therefore, targeting IL-1β secreted by MDSCs may be a potential immunotherapeutic strategy for the treatment of CRC.

Identifying polyamine related biomarkers in diagnosis and treatment of ulcerative colitis by integrating bulk and single-cell sequencing data

Ulcerative colitis (UC) is a chronic inflammatory disorder of the colon, and its pathogenesis remains unclear. Polyamine metabolic enzymes play a crucial role in UC. In this study, we aimed to identify pivotal polyamine-related genes (PRGs) and explore the underlying mechanism between PRGs and the disease status and therapeutic response of UC. We analyzed mRNA-sequencing data and clinical information of UC patients from the GEO database and identified NNMT, PTGS2, TRIM22, TGM2, and PPARG as key PRGs associated with active UC using differential expression analysis and weighted gene co-expression network analysis (WCGNA). Receiver operator characteristic curve (ROC) analysis confirmed the accuracy of these key genes in UC and colitis-associated colon cancer (CAC) diagnosis, and we validated their relationship with therapeutic response in external verification sets. Additionally, single-cell analysis revealed that the key PRGs were specific to certain immune cell types, emphasizing the vital role of intestinal tissue stem cells in active UC. The results were validated in vitro and in vivo experiments, including the colitis mice model and CAC mice model. In conclusion, these key PRGs effectively predict the progression of UC patients and could serve as new pharmacological biomarkers for the therapeutic response of UC.

PET imaging of colon cancer CD73 expression using cysteine site-specific 89Zr-labeled anti-CD73 antibody

CD73 is a cell-surface ectoenzyme that hydrolyzes the conversion of extracellular adenosine monophosphate to adenosine, which in turn can promote resistance to immune checkpoint blockade therapy. Immune response may therefore be improved by targeting tumor CD73, and this possibility underlines the need to non-invasively assess tumor CD73 level. In this study, we developed a cysteine site-specific 89Zr-labeled anti-CD73 (89Zr-CD73) IgG immuno-PET technique that can image tumor CD73 expression in living bodies. Anti-CD73 IgG was reduced with tris(2-carboxyethyl)phosphine, underwent sulfohydryl moiety–specific conjugation with deferoxamine–maleimide, and was radiolabeled with 89Zr. CT26 mouse colon cancer cells, CT26/CD73 cells engineered to constitutively overexpress CD73, and 4T1.2 mouse breast cancer cells underwent cell binding assays and western blotting. Balb/c nude mice bearing tumors underwent 89Zr-CD73 IgG PET imaging and biodistribution studies. 89Zr-CD73 IgG showed 20-fold higher binding to overexpressing CT26/CD73 cells compared to low-expressing CT26 cells, and moderate expressing 4T1.2 cells showed uptake that was 38.9 ± 1.51% of CT26/CD73 cells. Uptake was dramatically suppressed by excess unlabeled antibody. CD73 content proportionately increased in CT26 and CT26/CD73 cell mixtures was associated with linear increases in 89Zr-CD73 IgG uptake. 89Zr-CD73 IgG PET/CT displayed clear accumulation in CT26/CD73 tumors with greater uptake compared to CT26 tumors (3.13 ± 1.70%ID/g vs. 1.27 ± 0.31%ID/g at 8 days; P = 0.04). Specificity was further supported by low CT26/CD73 tumor-to-blood ratio of 89Zr-isotype-IgG compared to 89Zr-CD73 IgG (0.48 ± 0.08 vs. 2.68 ± 0.52 at 4 days and 0.53 ± 0.07 vs. 4.81 ± 1.02 at 8 days; both P < 0.001). Immunoblotting and immunohistochemistry confirmed strong CD73 expression in CT26/CD73 tumors and low expression in CT26 tumors. 4T1.2 tumor mice also showed clear 89Zr-CD73 IgG accumulation at 8 days (3.75 ± 0.70%ID/g) with high tumor-to-blood ratio compared to 89Zr-isotype-IgG (4.91 ± 1.74 vs. 1.20 ± 0.28; P < 0.005). 89Zr-CD73 IgG specifically targeted CD73 on high expressing cancer cells in vitro and tumors in vivo. Thus, 89Zr-CD73 IgG immuno-PET may be useful for the non-invasive monitoring of CD73 expression in tumors of living subjects.

KS‐133/KS‐487 Nanoparticles Exhibit Potent Antitumor Effects through Synergistic LRP1 Targeting and VIPR2 Inhibition: Therapeutic Nanoarchitectonics for Solid Tumors

AbstractVIPR2 is associated with psychiatric disorders, breast cancer metastasis, and cancer immunostimulation. The VIPR2 antagonist KS‐133 changes the polarity of macrophages to the M1 type, and nanoparticles (NPs) releasing KS‐133 exhibit antitumor effects against mouse colon cancer cells (CT26) in vivo. To enhance the antitumor effect of KS‐133 NPs, KS‐133 NPs are combined with the peptide KS‐487 targeting LRP1, which is expressed on CT26 cells. Subcutaneous injection of NPs containing indocyanine green (ICG) fluorescent dye and presenting KS‐487 in CT26 subcutaneous tumor‐bearing mice resulted in significant accumulation of ICG in the CT26 tumor compared to administration of NPs without KS‐487. NPs containing KS‐133 and presenting KS‐487 (KS‐133/KS‐487 NPs) exhibited dose‐dependent antitumor effects in CT26 subcutaneous tumor‐bearing mice; the antitumor effects are more potent than the effects of KS‐133 NPs without KS‐487. In addition, CD8‐positive T cells and macrophages significantly infiltrated into CT26 tumors after injection of KS‐133/KS‐487 NPs. Thus, KS‐133/KS‐487 NPs efficiently deliver KS‐133 to CT26 tumors via LRP1‐targeting and activate immune system cells such as CD8 positive T cells and macrophages via KS‐133 inhibition of VIPR2 signaling, resulting in antitumor effects. These results demonstrate the potential of KS‐133/KS‐487 NPs as a therapeutic candidate for treating solid tumors.

Engineering Thermo/pH-Responsive Lactoferrin Nanostructured Microbeads for Oral Targeting of Colorectal Cancer.

Colorectal cancer is an extremely aggressive form of cancer that often leads to death. Lactoferrin shows potential for targeting and treating colorectal cancer; however, oral delivery faces hurdles hampering clinical applications. We engineered dual-responsive lactoferrin nanostructured microbeads to overcome delivery hurdles and enhance drug targeting. The hydrophobic drug mesalazine (MSZ) was coupled to lactoferrin to form amphiphilic conjugate nanoparticles, dispersed in water. The lipid-soluble polyphenolic drug resveratrol (RSV) was then encapsulated into the hydrophobic core of LF-MSZ nanoparticles. To impart thermoresponsive properties, the dual-payload NPs were coupled with a PNIPAAm shell; finally, to further endow the nanoparticles with gastrointestinal resistance and pH responsiveness, the nanoparticles were microencapsulated into ionically cross-linked pectin-alginate beads. The nanoparticles showed enhanced internalization and cytotoxicity against HCT colon cancer cells via LF-receptor-mediated endocytosis. Thermal triggering and tuned release were conferred by the temperature-sensitive polymer. The coatings protected the drugs from degradation. Orally delivered microbeads significantly reduced tumor burden in a mouse colon cancer model, lowering carcinoembryonic antigen and elevating antioxidant enzymes. Apoptotic pathways were stimulated, indicated by heightened Bax/Bcl2 ratio and caspase-3/9 expression. Overall, we propose the innovative lactoferrin nanostructured microbeads as a paradigm shift in oral colorectal cancer therapeutics.

Intake of Special Amino Acids Mixture Leads to Blunted Murine Colon Cancer Growth In Vitro and In Vivo.

Cancer cells require substantial amounts of energy and substrates for their metabolic hyperactivity, enabling the synthesis of new cells at the expense of healthy ones. Preliminary in vitro data suggest that a mix of free essential amino acids (EAA-mix) can promote cancer cell apoptosis by enhancing autophagy. This study aimed to confirm, both in vitro and in vivo, whether EAA intake could influence the development of colon cancer in mice. We investigated changes in cancer proliferation in CT26 cells treated with EAA-mix and in mice fed with EAA-rich modified diets (EAARD) as compared to those on a standard laboratory diet (StD). CT26 cells were injected subcutaneously (s.c.) or intraperitoneally (i.p.). After 21 days, tumors were removed and measured. In vitro data corroborated that EAA-mix impairs cancer growth by inducing apoptosis. In vivo data revealed that mice on StD developed significantly larger (s.c.) and more numerous (i.p.) cancers than those on EAARD. EAA administration appears to influence cancer cell survival with notable antiproliferative properties.

Anti-TNFR2 Antibody-Conjugated PLGA Nanoparticles for Targeted Delivery of Adriamycin in Mouse Colon Cancer.

High levels of tumor necrosis factor receptor type II (TNFR2) are preferentially expressed by immunosuppressive CD4+Foxp3+ regulatory T cells (Tregs), especially those present in the tumor microenvironment, as initially reported by us. There is compelling evidence that targeting TNFR2 markedly enhances antitumor immune responses. Furthermore, a broad spectrum of human cancers also expresses TNFR2, while its expression by normal tissue is very limited. We thus hypothesized that TNFR2 may be harnessed for tumor-targeted delivery of chemotherapeutic agents. In this study, we performed a proof-of-concept study by constructing a TNFR2-targeted PEGylated poly(dl-lactic-co-glycolic acid) (PLGA-PEG) nanodrug delivery system [designated as TNFR2-PLGA-ADR (Adriamycin)]. The results of invitro study showed that this TNFR2-targeted delivery system had the properties in cellular binding and cytotoxicity toward mouse colon cancer cells. Further, upon intravenous injection, TNFR2-PLGA-ADR could efficiently accumulate in MC38 and CT26 mouse colon tumor tissues and preferentially bind with tumor-infiltrating Tregs. Compared with ADR and ISO-PLGA-ADR, the invivo antitumor effect of TNFR2-PLGA-ADR was markedly enhanced, which was associated with a decrease of TNFR2+ Tregs and an increase of IFNγ+CD8+ cytotoxic T lymphocytes in the tumor tissue. Therefore, our results clearly show that targeting TNFR2 is a promising strategy for designing tumor-specific chemoimmunotherapeutic agent delivery system.

Baicalin Prevents Colon Cancer by Suppressing CDKN2A Protein Expression.

To observe the therapeutic effects and underlying mechanism of baicalin against colon cancer. The effects of baicalin on the proliferation and growth of colon cancer cells MC38 and CT26. WT were observed and predicted potential molecular targets of baicalin for colon cancer therapy were studied by network pharmacology. Furthermore, molecular docking and drug affinity responsive target stability (DARTS) analysis were performed to confirm the interaction between potential targets and baicalin. Finally, the mechanisms predicted by in silico analyses were experimentally verified in-vitro and in-vivo. Baicalin significantly inhibited proliferation, invasion, migration, and induced apoptosis in MC38 and CT26 cells (all P<0.01). Additionally, baicalin caused cell cycle arrest at the S phase, while the G0/G1 phase was detected in the tiny portion of the cells. Subsequent network pharmacology analysis identified 6 therapeutic targets associated with baicalin, which potentially affect various pathways including 39 biological processes and 99 signaling pathways. In addition, molecular docking and DARTS predicted the potential binding of baicalin with cyclin dependent kinase inhibitor 2A (CDKN2A), protein kinase B (AKT), caspase 3, and mitogen-activated protein kinase (MAPK). In vitro, the expressions of CDKN2A, MAPK, and p-AKT were suppressed by baicalin in MC38 and CT26 cells. In vivo, baicalin significantly reduced the tumor size and weight (all P<0.01) in the colon cancer mouse model via inactivating p-AKT, CDKN2A, cyclin dependent kinase 4, cyclin dependent kinase 2, interleukin-1, tumor necrosis factor α, and activating caspase 3 and mouse double minute 2 homolog signaling (all P<0.05). Baicalin suppressed the CDKN2A protein level to prevent colon cancer and could be used as a therapeutic target for colon cancer.

Lipid Nanoparticular Codelivery System for Enhanced Antitumor Effects by Ferroptosis-Apoptosis Synergistic with Programmed Cell Death-Ligand 1 Downregulation.

Intrinsic or acquired resistance to chemical drugs severely limits their therapeutic efficacy in cancer treatment. Various intracellular antioxidant molecules, particularly glutathione (GSH), play a crucial role in maintaining intracellular redox homeostasis by mitigating the overproduced reactive oxygen species (ROS) due to rapid cell proliferation. Notably, these antioxidants also eliminate chemical-drug-induced ROS, eventually diminishing their cytotoxicity and rendering them less effective. In this study, we combined erastin, a GSH biosynthesis inhibitor, with 2'-deoxy-5-fluorouridine 5'-monophosphate sodium salt (FdUMP), an ROS-based drug, to effectively disrupt intracellular redox homeostasis and reverse chemotherapy resistance. Therefore, efficient ferroptosis and apoptosis were simultaneously induced for enhanced antitumor effects. Additionally, we employed small interfering RNA targeting PD-L1 (siPD-L1) as a third agent to block immune-checkpoint recognition by CD8+ T cells. The highly immunogenic cell peroxidates or damage-associated molecular patterns (DAMPs) induced by erastin acted synergistically with downregulated PD-L1 to enhance the antitumor effects. To codeliver these three drugs simultaneously and efficiently, we designed GE11 peptide-modified lipid nanoparticles (LNPs) containing calcium phosphate cores to achieve high encapsulation efficiencies. In vitro studies verified its enhanced cytotoxicity, efficient intracellular ROS induction and GSH/GPX4 downregulation, substantial lipid peroxidation product accumulation, and mitochondrial depolarization. In vivo, this formulation effectively accumulated at tumor sites and achieved significant tumor inhibition in subcutaneous colon cancer (CRC) mouse models with a maximum tumor inhibition rate of 83.89% at a relatively low dose. Overall, a strategy to overcome clinical drug resistance was verified in this study by depleting GSH and activating adaptive immunity.

ATXN3 functions as a tumor suppressor through potentiating galectin-9-mediated apoptosis in human colon adenocarcinoma

While the deubiquitinase ATXN3 has been implicated as a potential oncogene in various types of human cancers, its role in colon adenocarcinoma remains understudied. Surprisingly, our findings demonstrate that ATXN3 exerts an anti-tumor effect in human colon cancers through potentiating Galectin-9-induced apoptosis. CRISPR-mediated ATXN3 deletion unexpectedly intensified colon cancer growth both in vitro and in xenograft colon cancers. At the molecular level, we identified ATXN3 as a bona fide deubiquitinase specifically targeting Galectin-9, as ATXN3 interacted with and inhibited Galectin-9 ubiquitination. Consequently, targeted ATXN3 ablation resulted in reduced Galectin-9 protein expression, thereby diminishing Galectin-9-induced colon cancer apoptosis and cell growth arrest. The ectopic expression of Galectin-9 fully reversed the growth of ATXN3-null colon cancer in mice. Furthermore, immunohistochemistry staining revealed a significant reduction in both ATXN3 and Galectin-9 protein expression, along with a positive correlation between them in human colon cancer. Our study identifies the first Galectin-9-specific deubiquitinase and unveils a tumor-suppressive role of ATXN3 in human colon cancer.

A computational pipeline for identifying gene targets and signalling pathways in cancer cells to improve lymphocyte infiltration and immune checkpoint therapy efficacy

Tumour-infiltrating lymphocytes (TILs) are crucial for effective immune checkpoint blockade (ICB) therapy in solid tumours. However, ∼70% of these tumours exhibit poor lymphocyte infiltration, rendering ICB therapies less effective. We developed a bioinformatics pipeline integrating multiple previously unconsidered factors or datasets, including tumour cell immune-related pathways, copy number variation (CNV), and single tumour cell sequencing data, as well as tumour mRNA-seq data and patient survival data, to identify targets that can potentially improve T cell infiltration and enhance ICB efficacy. Furthermore, we conducted wet-lab experiments and successfully validated one of the top-identified genes. We applied this pipeline in solid tumours of the Cancer Genome Atlas (TCGA) and identified a set of genes in 18 cancer types that might potentially improve lymphocyte infiltration and ICB efficacy, providing a valuable drug target resource to be further explored. Importantly, we experimentally validated SUN1, which had not been linked to T cell infiltration and ICB therapy previously, but was one of the top-identified gene targets among 3 cancer types based on the pipeline, in a mouse colon cancer syngeneic model. We showed that Sun1 KO could significantly enhance antigen presentation, increase T-cell infiltration, and improve anti-PD1 treatment efficacy. Moreover, with a single-cell multiome analysis, we identified subgene regulatory networks (sub-GRNs) showing Stat proteins play important roles in enhancing the immune-related pathways in Sun1-KO cancer cells. This study not only established a computational pipeline for discovering new gene targets and signalling pathways in cancer cells that block T-cell infiltration, but also provided a gene target pool for further exploration in improving lymphocyte infiltration and ICB efficacy in solid tumours. A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

Characteristics of lipid metabolism after treatment of colon cancer mice with American ginseng vesicles.

Lipid molecules are present in tumours and play an important role in the anti-inflammatory response as well as in antiviral protection. Changes in the type and location of lipids in the intestine following exposure to environmental stressors play an important role in several disorders, including ulcerative colitis (UC), inflammatory bowel disease (IBD), and colorectal cancer. The aim of this work is to provide a new theoretical basis for tumour initiation and development by accurately measuring the spatial distribution of lipids and metabolites in intestinal tissue. Spatial metabolomics allows the detection of samples with minimal sample volume by label-free imaging of complex samples in their original state. The distribution of lipid molecules in tumours has not been reported, although the distribution of lipid molecules in intestinal tissue has been reported in the literature. The range of lipid profiles in colon cancer mouse tumour tissue was compiled using a spatial metabolomics: lipid extraction method. The changes in lipid distribution in two regions after oral administration of American Ginseng (Panax quinquefolius L.) vesicles were also compared. Tumour tissue samples were extracted with 80% methanol-20% formic acid in water. The resulting spatial metabolic profile allowed the identification of seven lipid classes in mouse tumours. The distribution of fibre tissue cells was 23.2% higher than tumour tissue cells, with the exception of the fatty acid (FA) species.