Animal Models Of Colon Cancer Research Articles

Proteomic study of medicinal mushroom extracts reveals antitumor mechanisms in an advanced colon cancer animal model via ribosomal biogenesis, translation, and metabolic pathways

Proteomic study of medicinal mushroom extracts reveals antitumor mechanisms in an advanced colon cancer animal model via ribosomal biogenesis, translation, and metabolic pathways

Mucosal-associated invariant T cells modulate innate immune cells and inhibit colon cancer growth.

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that can be activated by microbial antigens and cytokines and are abundant in mucosal tissues including the colon. MAIT cells have cytotoxic and pro-inflammatory functions and have potentials for use as adoptive cell therapy. However, studies into their anti-cancer activity, including their role in colon cancer, are limited. Using an animal model of colon cancer, we showed that peritumoral injection of invivo-expanded MAIT cells into RAG1-/- mice with MC38-derived tumours inhibits tumour growth compared to control. Multiplex cytokine analyses showed that tumours from the MAIT cell-treated group have higher expression of markers for eosinophil-activating cytokines, suggesting a potential association between eosinophil recruitment and tumour inhibition. In a human peripheral leukocyte co-culture model, we showed that leukocytes stimulated with MAIT ligand showed an increase in eotaxin-1 production and activation of eosinophils, associated with increased cancer cell killing. In conclusion, we showed that MAIT cells have a protective role in a murine colon cancer model, associated with modulation of the immune response to cancer, potentially involving eosinophil-associated mechanisms. Our results highlight the potential of MAIT cells for non-donor restricted colon cancer immunotherapy.

Paradoxical Activation of Oncogenic Signaling as a Cancer Treatment Strategy.

Cancer homeostasis depends on a balance between activated oncogenic pathways driving tumorigenesis and engagement of stress response programs that counteract the inherent toxicity of such aberrant signaling. Although inhibition of oncogenic signaling pathways has been explored extensively, there is increasing evidence that overactivation of the same pathways can also disrupt cancer homeostasis and cause lethality. We show here that inhibition of protein phosphatase 2A (PP2A) hyperactivates multiple oncogenic pathways and engages stress responses in colon cancer cells. Genetic and compound screens identify combined inhibition of PP2A and WEE1 as synergistic in multiple cancer models by collapsing DNA replication and triggering premature mitosis followed by cell death. This combination also suppressed the growth of patient-derived tumors in vivo. Remarkably, acquired resistance to this drug combination suppressed the ability of colon cancer cells to form tumors in vivo. Our data suggest that paradoxical activation of oncogenic signaling can result in tumor-suppressive resistance. Significance: A therapy consisting of deliberate hyperactivation of oncogenic signaling combined with perturbation of the stress responses that result from this is very effective in animal models of colon cancer. Resistance to this therapy is associated with loss of oncogenic signaling and reduced oncogenic capacity, indicative of tumor-suppressive drug resistance.

Synthesis and sonodynamic performance of spinel ferrites

Sonodynamic therapy has emerged as one of the most valuable treatment methods with low side effects and deep tissue penetration. As a representative inorganic sonosensitizer, spinel-type ferrites have many advantages such as high reactive oxygen species (ROS) production efficiency and stability. However, current studies have not explored how metal doping impacts the sonodynamic effect of spinel ferrites. Herein, we synthesized three kinds of spinel ferrite nanoparticles (ZnFe2O4, CoFe2O4, and MgFe2O4) and systematically investigated their sonodynamic performance. It is shown that three spinel ferrites are capable of producing singlet oxygen under ultrasound irradiation. Hydrogen peroxide further enhances the production of singlet oxygen, increasing the production rate by 1.05–2.31 times. The simultaneous existence of Co2+/Co3+ and Fe2+/Fe3+ redox couples in CoFe2O4 could convert more efficiently hydrogen peroxide into oxygen through catalytic reaction, providing more oxygen to promote singlet oxygen production. Thus, CoFe2O4 exhibits higher production efficiency than ZnFe2O4 and MgFe2O4. In vitro experiments demonstrate the good biocompatibility of CoFe2O4 nanoparticles and high ability to effectively kill cancer cells under ultrasound irradiation. In addition, CoFe2O4 shows good therapeutic efficacy in animal models of colon cancer. These findings highlight the great potential of ferrite sonosensitizer for cancer treatment.

VAX014, an Oncolytic Therapy, Reduces Adenomas and Modifies Colon Microenvironment in Mouse Model of CRC.

Colorectal cancer (CRC) remains the third most common form of cancer and, despite its reduced mortality, results in over 50,000 deaths annually, highlighting the need for novel therapeutic approaches. VAX014 is a novel clinical-stage, oncolytic bacterial minicell-based therapy shown to elicit protective antitumor immune responses in cancer, but it has not been fully evaluated in CRC. Here, VAX014 was demonstrated to induce oncolysis in CRC cell lines in vitro and was evaluated in vivo, both as a prophylactic (before spontaneous development of adenomatous polyps) and as a neoadjuvant treatment using the Fabp-CreXApcfl468 preclinical animal model of colon cancer. As a prophylactic, VAX014 significantly reduced the size and number of adenomas without inducing long term changes in the gene expression of inflammatory, T helper 1 antitumor, and immunosuppression markers. In the presence of adenomas, a neoadjuvant VAX014 treatment reduced the number of tumors, induced the gene expression of antitumor TH1 immune markers in adenomas, and promoted the expansion of the probiotic bacterium Akkermansia muciniphila. The neoadjuvant VAX014 treatment was associated with decreased Ki67 proliferation in vivo, suggesting that VAX014 inhibits adenoma development through both oncolytic and immunotherapeutic effects. Combined, these data support the potential of VAX014 treatment in CRC and "at risk" polyp-bearing or early adenocarcinoma populations.

ANTIPROLIFERATIVE POTENTIAL OF ESCITALOPRAM IN DIMETHYLHYDRAZINE (DMH) INDUCED COLON CANCER IN SWISS ALBINO MICE

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems.This research emphasizes on pharmacological evaluation of anti-colon cancer effect of escitalopram in albino mice by using behavioral and hematological models. Animal House, Aryakul College of Pharmacy & Research, Lucknowprovided albino mice of either sex weighing 70-90g. All the animals were divided into 5 groups (n=6) Group 1 (NC): Mice are administered only 0.25% CMC once a week up to 28 days. Group 2 (CC): Mice are administered DMH (40mg/kg, o.d.) once a week up to 28 days. Group 3 (PC): Mice are administered DMH (40mg/kg, o.d.) once a week up to 28 days + Fluorouracil (10mg/kg) once a day for 15 days. Group 4 (T1): Mice are administered DMH (40mg/kg) once a week up to 28 days + Escitalopram (5mg/kg) once a day for 15 days. Group 5 (T2): Mice are administered DMH (40mg/kg) once in a week up to 28 days + Escitalopram (10mg/kg) once a day for 15 days.They were evaluated for parameters like determination of pH, acidity, of ALT, AST & LDH levels and estimation of lipid profile. The results of the current study demonstrate that Escitalopram administration influences ameliorating anticancer effects by altering several processes, including Phase I & II biotransformation. lipid peroxidation, enzymes, antioxidants, and histopatholgical alterations. It concluded that Escitalopram is effective in management of colon cancer in animal model. This study suggests that Escitalopram can also be given in the treatment of colorectal cancer in human beings after successful clinical trials.

Abstract 705: Potentiation of immunotherapy by LSD1 modulation

Abstract LSD1 has emerged as a potential therapeutic target to increase the effectiveness of cancer immunotherapy. We have developed a series of novel small molecules, exemplified by the lead substance BEA-17, that modulates LSD1 via binding to an allosteric site, without directly inhibiting its enzymatic activity. In cells, BEA-17 induces a reduction of LSD1 levels. In addition, BEA-17 upregulates the expression of endogenous retroviral genes and T cell-attractant chemokines and does so in an LSD1-dependent manner. In a co-culture of HeLa and PBMCs, BEA-17 increases cell kill of cancer cells by immune effector T cells, also in an LSD1-dependent manner. In a CT26 syngeneic animal model of colon cancer, BEA-17 potentiates the activity of anti-PD1 inhibitors. Finally, in a syngeneic GL261 animal model of glioblastoma, BEA-17 increases the effectiveness of standard-of-care temozolomide + radiation. Citation Format: Wei B. Emond, Rajiv Sawant, Matthis Geitmann, Johan Winquist, Peter Brandt, Ulf Bremberg, Per Källblad, Vendela Parrow, Claes Andersson, Kristin Blom, Nasrin Najafi, Tobias Bergström, Fredrik J. Swartling, Mats Hellström, Konrad F. Koehler. Potentiation of immunotherapy by LSD1 modulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 705.

Abstract 4140: Oncogenic KRAS inhibition with ADT-007 primes T cell responses in pancreatic ductal adenocarcinoma

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) has low (<11%) 5-year survival due to the presence of advanced disease at diagnosis. Currently standard of care provides a median survival of 1 year in the majority of patients presenting with advanced disease. Targeting oncogenic KRAS, which is mutated in >90% of human PDAC tumors, provides an opportunity to inhibit a critical pathway and significantly impact standard of care in patients diagnosed with PDAC. Furthermore, evidence indicates that inhibiting-oncogenic KRAS signaling modulates anti-tumor immune responses and demonstrates synergy with immune checkpoint blockade in pre-clinical models. The purpose of this study is to evaluate efficacy and impact on anti-tumor immunity of a novel inhibitor, ADT-007 that demonstrates pan-RAS inhibitory activity. Methods: Female C57BL/6J, C57BL/6J. Ifng/Thy1.1 KI;Cg-Tg-IL2tm1/eGFP/Weav (IFNg-Thy1.1/IL-2-GFP reporter mice), or immune deficient (T/B cells) Rag 1 −/− mice (n=5-10/group) were implanted SQ with 106 mouse derived PDAC cell lines (7160c2 and 2838c3) bearing KRASG12D mutation, and then randomized (day 7), into vehicle (5% DMSO/5% Kolliphor/90% H2O) or ADT-007 treatment, which was administered SQ (peritumoral), BID at 5 mg/kg for 2 - 3 weeks. Tumor growth in vitro (IC50), KRAS-MAPK/AKT signaling, in vivo tumor volumes (tv = L x W2/2), and tumor immune responses were assessed by CellTiter Glo, phosphoflow/western blotting, bi-weekly caliper measurements, and multi-parameter flow cytometry, respectively. Results: ADT-007 inhibited KRAS-MAPK/AKT signaling in human and mouse PDAC cell lines inducing G2-M phase arrest and apoptosis at low nanomolar concentrations. Peritumoral administration of ADT-007 inhibited tumor cell growth in vivo, modulating T cells in the tumor microenvironment (TME), specifically, an increase in tumor infiltrating, CD44+ CD62L− CD4+ and CD8+ T cells and increases in production of TNFα, IFN-γ, IL-2, and granzyme B upon stimulation with PMA/ionomycin. Conclusion: The small molecule inhibitor, ADT-007 blocks oncogenic KRAS signaling and modulates T cell activation and function in the TiME of immune competent, syngeneic mouse models of PDAC. More broadly, these findings indicate that a pan-RAS inhibitor is capable of modulating anti-tumor immune responses extending previous observations that targeted inhibition of oncogenic KRASG12C modulates tumor immunity in animal models of colon and lung cancer. Citation Format: Jeremy B. Foote, Tyler E. Mattox, Adam B. Keeton, Ganji N. Purnachandra, Yulia Maxuitenko, Xi Chen, Jacob Valiyaveettil, Donald J. Buchsbaum, Gary A. Piazza, Bassel F. El-Rayes. Oncogenic KRAS inhibition with ADT-007 primes T cell responses in pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4140.

Novel bispecific aptamer targeting PD-1 and nucleolin for cancer immunotherapy

BackgroundImmune checkpoint blockade (ICB) is a promising strategy for cancer treatment and has achieved remarkable clinical results. Further improvement of ICB efficacy may advance cancer immunotherapy and has evident medical importance. Here in this study, a PD-1 aptamer was functionalized with a tumor-homing nucleolin aptamer (AS1411) to build a novel bispecific agent (BiApt) for boosting the efficacy of ICB therapy.ResultsThe two aptamers were coupled together via sticky ends to form BiApt, which had an average size of 11.70 nm. Flow cytometry revealed that BiApt could bind with both the activated T cells and the nucleolin-expressing tumor cells. In addition, BiApt could recruit more T cells to the vicinity of nucleolin-positive tumor cells. Functionally, BiApt enhanced the PBMC-mediated anticancer cytotoxicity in vitro compared with free PD-1 aptamer. Moreover, in an animal model of CT26 colon cancer, BiApt significantly boosted the antitumor efficacy vs. free PD-1 aptamer.ConclusionThe results suggest that bispecific agent combining ICB and tumor-homing functions has potential to improve the efficacy of ICB immunotherapy.

Artificial Diets with Altered Levels of Sulfur Amino Acids Induce Anticancer Activity in Mice with Metastatic Colon Cancer, Ovarian Cancer and Renal Cell Carcinoma.

Sulfur-containing amino acids methionine (Met), cysteine (Cys) and taurine (Tau) are common dietary constituents with important cellular roles. Met restriction is already known to exert in vivo anticancer activity. However, since Met is a precursor of Cys and Cys produces Tau, the role of Cys and Tau in the anticancer activity of Met-restricted diets is poorly understood. In this work, we screened the in vivo anticancer activity of several Met-deficient artificial diets supplemented with Cys, Tau or both. Diet B1 (6% casein, 2.5% leucine, 0.2% Cys and 1% lipids) and diet B2B (6% casein, 5% glutamine, 2.5% leucine, 0.2% Tau and 1% lipids) showed the highest activity and were selected for further studies. Both diets induced marked anticancer activity in two animal models of metastatic colon cancer, which were established by injecting CT26.WT murine colon cancer cells in the tail vein or peritoneum of immunocompetent BALB/cAnNRj mice. Diets B1 and B2B also increased survival of mice with disseminated ovarian cancer (intraperitoneal ID8 Tp53-/- cells in C57BL/6JRj mice) and renal cell carcinoma (intraperitoneal Renca cells in BALB/cAnNRj mice). The high activity of diet B1 in mice with metastatic colon cancer may be useful in colon cancer therapy.

Repositioning of simvastatin for diabetic colon cancer: role of CDK4 inhibition and apoptosis.

There is increased risk of colon cancer in both men and women having diabetes. The objective of the study was to evaluate the role of simvastatin in colon cancer associated with type 2 diabetes mellitus. Diabetes was induced by administering high fat diet with low dose streptozotocin model. 1,2 dimethylhydrazine (25mg/kg, sc) was used for colon cancer induction. MTT assay, scratch assay, clonogenic assay and annexin V-FITC assay using flow cytometry were performed on HCT-15 cell line. Simvastatin controlled diabetes and colon cancer in animal models and reduced mRNA expression of CDK4 in colon tissues. In vitro studies revealed that simvastatin showed a decrease in cell viability and produced dose dependent decrease in clone formation. There was decrease in the rate of migration with increase in concentration of simvastatin in scratch assay. Moreover, simvastatin induced apoptosis as depicted from annexin V-FITC assay using flow cytometry as well as that revealed by tunnel assay. Our data suggest that simvastatin exhibits protective role in colon cancer associated with diabetes mellitus and acts possibly via down regulation of CDK4 and induction of apoptosis and hence can be considered for repositioning in diabetic colon cancer.

MICRO-RNA DETECTION FOR THE DIAGNOSIS OF COLON CANCER IN A MURINE MODEL

Abstract Introduction The main objective of this study was to characterise an animal model of colon cancer in the F344-ApcPircUwm rat through the analysis of microRNAs expressed in plasma by Next Generation Sequencing. Methods Colonoscopic follow-ups of the colon cancer model were performed for 10 months (n=60). At each follow-up, 2 ml of whole blood was collected in EDTA tubes, centrifuged for plasma extraction and frozen at - 80 °C. After euthanasia of the animals the different regions of the colon and their respective findings were analysed by histopathological analysis to obtain a ground truth. After this, 14 plasma samples were analysed by Next Generation Sequencing to observe the different expressions of microRNAs between the animals corresponding to the Neoplasia group and the healthy animals (n=6/8). Results After the corresponding functional analysis of the microRNAs deregulated in the animals of the colonic adenoma group and the healthy animals, we highlight rno-miR-192–5p, rno-miR-125b-5p and rno-miR-29c-3p, which appear underexpressed in the animals with adenomatous and adenocarcinomatous lesions in the colon. Conclusions The microRNAs deregulated in this animal model compared to their healthy counterpart without lesions obtained by liquid biopsy are miR-125b-5p, miR-192–5p and miR-29c-3p and their study could open the door to novel therapeutic strategies for prognosis and diagnosis by studying their expression in animal models that could be transferred to humans in the fight against colon cancer.

Short-chain fatty acids reprogram metabolic profiles with the induction of reactive oxygen species production in human colorectal adenocarcinoma cells

Short-chain fatty acids (SCFAs) exhibit anticancer activity in cellular and animal models of colon cancer. Acetate, propionate, and butyrate are the three major SCFAs produced from dietary fiber by gut microbiota fermentation and have beneficial effects on human health. Most previous studies on the antitumor mechanisms of SCFAs have focused on specific metabolites or genes involved in antitumor pathways, such as reactive oxygen species (ROS) biosynthesis. In this study, we performed a systematic and unbiased analysis of the effects of acetate, propionate, and butyrate on ROS levels and metabolic and transcriptomic signatures at physiological concentrations in human colorectal adenocarcinoma cells. We observed significantly elevated levels of ROS in the treated cells. Furthermore, significantly regulated signatures were involved in overlapping pathways at metabolic and transcriptomic levels, including ROS response and metabolism, fatty acid transport and metabolism, glucose response and metabolism, mitochondrial transport and respiratory chain complex, one-carbon metabolism, amino acid transport and metabolism, and glutaminolysis, which are directly or indirectly linked to ROS production. Additionally, metabolic and transcriptomic regulation occurred in a SCFAs types-dependent manner, with an increasing degree from acetate to propionate and then to butyrate. This study provides a comprehensive analysis of how SCFAs induce ROS production and modulate metabolic and transcriptomic levels in colon cancer cells, which is vital for understanding the mechanisms of the effects of SCFAs on antitumor activity in colon cancer.

Artificial Diets Based on Selective Amino Acid Restriction versus Capecitabine in Mice with Metastatic Colon Cancer.

New therapies are needed to improve the low survival rates of patients with metastatic colon cancer. Evidence suggests that amino acid (AA) restriction can be used to target the altered metabolism of cancer cells. In this work, we evaluated the therapeutic potential of selective AA restriction in colon cancer. After observing anticancer activity in vitro, we prepared several artificial diets and evaluated their anticancer activity in two challenging animal models of metastatic colon cancer. These models were established by injecting CT26.WT murine colon cancer cells in the peritoneum (peritoneal dissemination) or in the tail vein (pulmonary metastases) of immunocompetent BALB/cAnNRj mice. Capecitabine, which is a first-line treatment for patients with metastatic colon cancer, was also evaluated in these models. Mice fed diet TC1 (a diet lacking 10 AAs) and diet TC5 (a diet with 6% casein, 5% glutamine, and 2.5% leucine) lived longer than untreated mice in both models; several mice survived the treatment. Diet TC5 was better than several cycles of capecitabine in both cancer models. Cysteine supplementation blocked the activity of diets TC1 and TC5, but cysteine restriction was not sufficient for activity. Our results indicated that artificial diets based on selective AA restriction have therapeutic potential for colon cancer.

Role of aerobic exercise training on tumor‐infiltrated immune cells

BackgroundDespite the remarkable treatment progress in the last decades, cancer remains the second leading cause of death in the world. Therefore, strategies capable of attenuating tumor initiation, progression and aggressiveness are important for reducing incidence and mortality caused by cancer. Considering this, it is well known that aerobic exercise training (AET) promotes several beneficial adaptations in the body, and it has emerged as a possible strategy to attenuate tumor progression. However, the mechanisms underlining the beneficial effects of AET on tumor progression are still unclear. Aim: Therefore, this study intended to evaluate whether AET could positively modify the tumor microenvironment, favoring infiltration of “antitumor” immune cells, and/or reducing the amount of “protumor” immune cells, consequently attenuating tumor progression.MethodsTo test this, Balb/c mice were submitted to a moderate intensity AET (60% of maximal aerobic capacity, 5 days/week, 1 hour/day, in a treadmill) for 1 month before being inoculated with 1x106 CT26 colon carcinoma cells (subcutaneous injection). The AET protocol was maintained during tumor progression, and the last exercise session was performed 48 hours before animals were sacrificed (9 days after tumor cells inoculation). Tumor volume and body weight were measured daily. Experimental groups were divided into control (healthy sedentary mice), CT26 SED (sedentary tumor‐bearing mice) and CT26 TR (trained tumor‐bearing mice). Tumors were harvested at day 9 and digested with collagenase IV and DNAse. After that, tumor leukocytes were separated by a Percoll gradient. Tumor‐infiltrated dendritic cells, macrophages, natural killer cells (NK), and T lymphocytes were measured by flow cytometry. Statistical analysis: Anova One‐way, Duncan post hoc, p<0.05. Ethical committee approval: CEUA EEFE‐USP 2017/02.ResultsTumor‐bearing mice submitted to AET presented an attenuated tumor progression when compared with CT26 SED group, with significant reduction in tumor volume and mass (ex vivo). AET significantly increased the total amount of tumor‐infiltrated leukocytes (CD45+), which included an increase in the percentage of NK cells, total, activated and effector memory CD8+ T cells, and effector memory CD4+ T cells in CT26 TR when compared to CT26 SED. Although there were no significant changes in the tumor amount of total and activated CD4+ T cells, the CD4+/CD8+ ratio was significantly reduced in CT26 TR comparing with CT26 SED mice, suggesting that the balance between CD4+ and CD8+ T cells in trained mice tumors favored a cytotoxic/effector T lymphocyte profile. Moreover, the percentage of tumor‐infiltrated regulatory T cells (Tregs) in CT26 TR was significantly decreased when compared to CT26 SED mice. No significant changes were found for dendritic cells and macrophages (types M1 and M2).ConclusionAET increases tumor‐infiltrated amounts of cytotoxic/effector immune cells, such as NK and CD8+ T cells, while decreasing the percentage of Tregs in a colon cancer animal model. These data suggest that AET can attenuate tumor growth by modulation of tumor‐infiltrated immune cells number and profile.

A siRNA-Assisted Assembly Strategy to Simultaneously Suppress "Self" and Upregulate "Eat-Me" Signals for Nanoenabled Chemo-Immunotherapy.

Effectively activating macrophages that can engulf cancer cells is a promising immunotherapeutic strategy but remains a major challenge due to the expression of "self" signals (e.g., CD47 molecules) by tumor cells to prevent phagocytosis. Herein, we explored a siRNA-assisted assembly strategy for the simultaneous delivery of siRNA and mitoxantrone hydrochloride (MTO·2HCl) via PLGA-based nanoparticles. The siRNA suppressed a "self" signal by silencing the CD47 gene, while the MTO induced surface exposure of calreticulin (CRT) to provide an "eat-me" signal. The siRNA-assisted assembly strategy synergistically increased the phagocytosis of tumor cells by macrophages, promoted effective antigen presentation, and initiated T cell-mediated immune responses in two aggressive tumor animal models of melanoma and colon cancer, eventually achieving significantly improved antitumor activity. This study provides a straightforward codelivery strategy to simultaneously suppress "self" and upregulate "eat-me" signals to potentiate macrophage-mediated immunotherapy.

Akkermansia Muciniphila Potentiates the Antitumor Efficacy of FOLFOX in Colon Cancer.

FOLFOX (oxaliplatin, fluorouracil and calcium folinate) is the first-line chemotherapy regimen for colon cancer therapy in the clinic. It provides superior efficacy than oxaliplatin alone, but the underlying mechanism remains unclear. In the present study, pharmacomicrobiomics integrated with metabolomics was conducted to uncover the role of the gut microbiome behind this. First, in vivo study demonstrated that FOLFOX exhibited better efficacy than oxaliplatin alone in colon cancer animal models. Second, 16S rDNA gene sequencing analysis showed that the abundance of Akkermansia muciniphila (A. muciniphila) remarkably increased in the FOLFOX treated individuals and positively correlated with the therapeutic effect. Third, further exploration confirmed A. muciniphila colonization significantly enhanced the anti-cancer efficacy of FOLFOX. Last, metabolomics analysis suggested dipeptides containing branched-chain amino acid (BCAA) might be responsible for gut bacteria mediated FOLFOX efficacy. In conclusion, our study revealed the key role of A. muciniphila in mediating FOLFOX efficacy, and manipulating A. muciniphila might serve as a novel strategy for colon cancer therapy.

Preclinical Evaluation of Recombinant Human IL15 Protein Fused with Albumin Binding Domain on Anti-PD-L1 Immunotherapy Efficiency and Anti-Tumor Immunity in Colon Cancer and Melanoma.

Simple SummaryIn this manuscript, we reported that a newly developed recombinant human IL15 fused with albumin binding domain (hIL15-ABD) showed superior biological half-life, pharmacokinetic and anti-tumor immunity than wild-type (WT) hIL15. Our hIL-15-ABD can effectively enhance anti-tumor efficacy of anti-PD-L1 on colon cancer and melanoma animal models. The anti-tumor potential of hIL-15-ABD was associated with tumor microenvironment (TME) regulation, including the activation of NK cells and CD8+ T cells, the reduction of immunosuppressive cells (MDSCs and Tregs) and the suppression of immunosuppressive factors (IDO, FOXP3 and VEGF). In conclusion, our new hIL15-ABD combined with anti-PD-L1 antibody increased the activity of anti-tumor effector cells involved in both innate and adaptive immunities, decreased the TME’s immunosuppressive cells, and showed greater anti-tumor effect than that of either monotherapy. We suggested hIL15-ABD as the potential complementary agent may effectively augment the therapeutic efficacy of anti-PD-L1 antibody in colon cancer and melanoma model.Anti-PD-L1 antibody monotherapy shows limited efficacy in a significant proportion of the patients. A common explanation for the inefficacy is a lack of anti-tumor effector cells in the tumor microenvironment (TME). Recombinant human interleukin-15 (hIL15), a potent immune stimulant, has been investigated in clinical trial with encouraging results. However, hIL15 is constrained by the short half-life of hIL15 and a relatively unfavorable pharmacokinetics profile. We developed a recombinant fusion IL15 protein composed of human IL15 (hIL15) and albumin binding domain (hIL15-ABD) and explored the therapeutic efficacy and immune regulation of hIL-15, hIL15-ABD and/or combination with anti-PD-L1 on CT26 murine colon cancer (CC) and B16-F10 murine melanoma models. We demonstrated that hIL15-ABD has significant inhibitory effect on the CT26 and B16-F10 tumor growths as compared to hIL-15. hIL-15-ABD not only showed superior half-life and pharmacokinetics data than hIL-15, but also enhance anti-tumor efficacy of antibody against PD-L1 via suppressive effect on accumulation of Tregs and MDSCs and activation of NK and CD8+T cells. Immune suppressive factors including VEGF and IDO were also decreased by combination treatment. hIL15-ABD combined with anti-PD-L1 antibody increased the activity of anti-tumor effector cells involved in both innate and adaptive immunities, decreased the TME’s immunosuppressive cells, and showed greater anti-tumor effect than that of either monotherapy.

A Simple Screening Test for Cancer

Comparative and correlative studies of the pathology and pathogenesis of colon cancer in animal models and human disease have resulted in conceptualization of ‘field effect” theory, and identification of a simple carbohydrate marker that is expressed early during carcinogenesis. This assimilated body of knowledge has resulted in development of a simple screening test for cancers of the lung, breast, colorectum, uterus, pancreas, and prostate. The marker galactose-N acetyl-galactosamine (Gal-GalNAc) is expressed in the cell surface and secreted glycoproteins of otherwise normal appearing tissues remote from cancer or precancerous lesions and is detected by enzymatic oxidation (10 minutes) followed by color reaction (1 minute). The high sensitivity, specificity, and cost-effectiveness of this point-of-care test makes it a great tool in our strategies for early detection, hence control of cancer. It would also reduce the number of unnecessary and expensive procedures, thereby decreasing the total national health-care cost to the societies and governments, globally.

Corticotropin-Releasing Hormone Receptor Alters the Tumor Development and Growth in Apcmin/+ Mice and in a Chemically-Induced Model of Colon Cancer.

The neuroendocrine circuit of the corticotropin-releasing hormone (CRH) family peptides, via their cognate receptors CRHR1 and CRHR2, copes with psychological stress. However, peripheral effects of the CRH system in colon cancer remains elusive. Thus, we investigate the role of CRHR1 and CRHR2 in colon cancer. Human colon cancer biopsies were used to measure the mRNA levels of the CRH family by quantitative real-time PCR. Two animal models of colon cancer were used: Apcmin/+ mice and azoxymethane (AOM)/dextran sulfate sodium (DSS)-treated mice. The mRNA levels of CRHR2 and UCN III are reduced in human colon cancer tissues compared to those of normal tissues. Crhr1 deletion suppresses the tumor development and growth in Apcmin/+ mice, while Crhr2 deficiency exacerbates the tumorigenicity. Crhr1 deficiency not only inhibits the expression of tumor-promoting cyclooxygenase 2, but also upregulates tumor-suppressing phospholipase A2 in Apcmin/+ mice; however, Crhr2 deficiency does not change these expressions. In the AOM/DSS model, Crhr2 deficiency worsens the tumorigenesis. In conclusion, Crhr1 deficiency confers tumor-suppressing effects in Apcmin/+ mice, but Crhr2 deficiency worsens the tumorigenicity in both Apcmin/+ and AOM/DSS-treated mice. Therefore, pharmacological inhibitors of CRHR1 or activators of CRHR2 could be of significance as anti-colon cancer drugs.