Abstract A07: Transcriptional profiling confirms appendiceal adenocarcinoma is distinct from colorectal cancer, in vivo models needed

BackgroundAlthough cancer immunotherapy is one of the most effective advanced-stage cancer therapies, no clinically approved cancer immunotherapies currently exist for colorectal cancer (CRC). Recently, programmed cell death protein 1 (PD-1) blockade has exhibited clinical benefits according to ongoing clinical trials. However, ongoing clinical trials for cancer immunotherapies are focused on PD-1 signaling inhibitors such as pembrolizumab, nivolumab, and atezolizumab. In this study, we focused on revealing the distinct response mechanism for the potent CD73 ectoenzyme selective inhibitor AB680 as a promising drug candidate that functions by blocking tumorigenic ATP/adenosine signaling in comparison to current therapeutics that block PD-1 to assess the value of this drug as a novel immunotherapy for CRC.MethodsTo understand the distinct mechanism of AB680 in comparison to that of a neutralizing antibody against murine PD-1 used as a PD-1 blocker, we performed single-cell RNA sequencing of CD45+ tumor-infiltrating lymphocytes from untreated controls (n=3) and from AB680-treated (n=3) and PD-1-blockade-treated murine CRC in vivo models. We also used flow cytometry, Azoxymethane (AOM)/Dextran Sulfate Sodium (DSS) models, and in vitro functional assays to validate our new findings.ResultsWe initially observed that the expressions of Nt5e (a gene for CD73) and Entpd1 (a gene for CD39) affect T cell receptor (TCR) diversity and transcriptional profiles of T cells, thus suggesting their critical roles in T cell exhaustion within tumor. Importantly, PD-1 blockade significantly increased the TCR diversity of Entpd1-negative T cells and Pdcd1-positive T cells. Additionally, we determined that AB680 improved the anticancer functions of immunosuppressed cells such as Treg and exhausted T cells, while the PD-1 blocker quantitatively reduced Malat1high Treg and M2 macrophages. We also verified that PD-1 blockade induced Treg depletion in AOM/DSS CRC in vivo models, and we confirmed that AB680 treatment caused increased activation of CD8+ T cells using an in vitro T cell assay.ConclusionsThe intratumoral immunomodulation of CD73 inhibition is distinct from PD-1 inhibition and exhibits potential as a novel anticancer immunotherapy for CRC, possibly through a synergistic effect when combined with PD-1 blocker treatments. This study may contribute to the ongoing development of anticancer immunotherapies targeting refractory CRC.

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Schisandrin B Attenuates Colitis-Associated Colorectal Cancer through SIRT1 Linked SMURF2 Signaling

The American Journal of Chinese Medicine ◽

10.1142/s0192415x21500841 ◽

2021 ◽

pp. 1-17

Author(s):

Zhichen Pu ◽

Weiwei Zhang ◽

Minhui Wang ◽

Maodi Xu ◽

Haitang Xie ◽

...

Keyword(s):

Colorectal Cancer ◽

Colon Cancer ◽

Cell Growth ◽

Protein Expression ◽

Hct116 Cell ◽

Enzyme Linked Immunosorbent Assay ◽

Schisandrin B ◽

In Vivo Models

Colon cancer, a common type of malignant tumor, seriously endangers human health. However, due to the relatively slow progress in diagnosis and treatment, the clinical therapeutic technology of colon cancer has not been substantially improved in the past three decades. The present study was designed to investigate the effects and involved mechanisms of schisandrin B in cell growth and metastasis of colon cancer. C57BL/6 mice received AOM and dextran sulfate sodium. Mice in treatment groups were gavaged with 3.75–30 mg/kg/day of schisandrin B. Transwell chamber migration, enzyme-linked immunosorbent assay (ELISA), Western blot analysis, immunoprecipitation (IP) and immunofluorescence were conducted, and HCT116 cell line was employed in this study. Data showed that schisandrin B inhibited tumor number and tumor size in the AOD+DSS-induced colon cancer mouse model. Schisandrin B also inhibited cell proliferation and metastasis of colon cancer cells. We observed that schisandrin B induced SMURF2 protein expression and affected SIRT1 in vitro and in vivo. SMURF2 interacted with SIRT1 protein, and there was a negative correlation between SIRT1 and SMURF2 expressions in human colorectal cancer. The regulation of SMURF2 was involved in the anticancer effects of schisandrin B in both in vitro and in vivo models. In conclusion, the present study revealed that schisandrin B suppressed SIRT1 protein expression, and SIRT1 is negatively correlated with the induction of SMURF2, which inhibited cell growth and metastasis of colon cancer. Schisandrin B could be a leading compound, which will contribute to finding novel potential agents and therapeutic targets for colon cancer.

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Development of Preclinical Models to Understand and Treat Colorectal Cancer

Clinics in Colon and Rectal Surgery ◽

10.1055/s-0037-1602240 ◽

2018 ◽

Vol 31 (03) ◽

pp. 199-204 ◽

Cited By ~ 3

Author(s):

Judith Sebolt-Leopold

Keyword(s):

Colorectal Cancer ◽

Colorectal Tumors ◽

Human Colorectal Cancer ◽

Preclinical Models ◽

In Vivo Models ◽

Molecular Determinants ◽

Experimental Therapies ◽

Molecular Aberrations

AbstractThe establishment and validation of preclinical models that faithfully recapitulate the pathogenesis and treatment response of human colorectal cancer (CRC) is critical to expedient therapeutic advances in the clinical management of this disease. Integral to the application of precision medicine for patients diagnosed with metastatic CRC is the need to understand the molecular determinants of response for a given therapy. Preclinical models of CRC have proven invaluable in answering many of our basic questions relating to the molecular aberrations that drive colorectal tumor progression. This review will address the comparative merits and limitations of the broad spectrum of in vitro and in vivo models available for study of colorectal tumors and their response to experimental therapies.

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Epithelial to mesenchymal plasticity and differential response to therapies in pancreatic ductal adenocarcinoma

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1914915116 ◽

2019 ◽

Vol 116 (52) ◽

pp. 26835-26845 ◽

Cited By ~ 7

Author(s):

Rebecca L. Porter ◽

Neelima K. C. Magnus ◽

Vishal Thapar ◽

Robert Morris ◽

Annamaria Szabolcs ◽

...

Keyword(s):

Pancreatic Ductal Adenocarcinoma ◽

Clinical Investigation ◽

Transcriptional Profiling ◽

Response To Therapy ◽

Ductal Adenocarcinoma ◽

Transcriptional Responses ◽

In Vivo Models ◽

Functional Changes ◽

The Impact

Transcriptional profiling has defined pancreatic ductal adenocarcinoma (PDAC) into distinct subtypes with the majority being classical epithelial (E) or quasi-mesenchymal (QM). Despite clear differences in clinical behavior, growing evidence indicates these subtypes exist on a continuum with features of both subtypes present and suggestive of interconverting cell states. Here, we investigated the impact of different therapies being evaluated in PDAC on the phenotypic spectrum of the E/QM state. We demonstrate using RNA-sequencing and RNA-in situ hybridization (RNA-ISH) that FOLFIRINOX combination chemotherapy induces a common shift of both E and QM PDAC toward a more QM state in cell lines and patient tumors. In contrast, Vitamin D, another drug under clinical investigation in PDAC, induces distinct transcriptional responses in each PDAC subtype, with augmentation of the baseline E and QM state. Importantly, this translates to functional changes that increase metastatic propensity in QM PDAC, but decrease dissemination in E PDAC in vivo models. These data exemplify the importance of both the initial E/QM subtype and the plasticity of E/QM states in PDAC in influencing response to therapy, which highlights their relevance in guiding clinical trials.

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microRNAs and Corresponding Targets Involved in Metastasis of Colorectal Cancer in Preclinical In Vivo Models

Cancer Genomics & Proteomics ◽

10.21873/cgp.20204 ◽

2020 ◽

Vol 17 (5) ◽

pp. 453-468

Author(s):

ULRICH H. WEIDLE ◽

ULRICH BRINKMANN ◽

SIMON AUSLAENDER

Keyword(s):

Colorectal Cancer ◽

In Vivo Models

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Estrogen Activation by Steroid Sulfatase Increases Colorectal Cancer Proliferation via GPER

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2016-3716 ◽

2017 ◽

Vol 102 (12) ◽

pp. 4435-4447 ◽

Cited By ~ 7

Author(s):

Lorna C Gilligan ◽

Habibur P Rahman ◽

Anne-Marie Hewitt ◽

Alice J Sitch ◽

Ali Gondal ◽

...

Keyword(s):

Colorectal Cancer ◽

Molecular Mechanisms ◽

Tissue Growth ◽

Estrogen Metabolism ◽

Data Set ◽

In Vivo Models ◽

Metabolism Enzymes ◽

Estradiol Synthesis

Abstract Context Estrogens affect the incidence and progression of colorectal cancer (CRC), although the precise molecular mechanisms remain ill-defined. Objective The present study investigated prereceptor estrogen metabolism through steroid sulphatase (STS) and 17β-hydroxysteroid dehydrogenase activity and subsequent nongenomic estrogen signaling in human CRC tissue, in The Cancer Genome Atlas colon adenocarcinoma data set, and in in vitro and in vivo CRC models. We aimed to define and therapeutically target pathways through which estrogens alter CRC proliferation and progression. Design, Setting, Patients, and Interventions Human CRC samples with normal tissue-matched controls were collected from postmenopausal female and age-matched male patients. Estrogen metabolism enzymes and nongenomic downstream signaling pathways were determined. CRC cell lines were transfected with STS and cultured for in vitro and in vivo analysis. Estrogen metabolism was determined using an ultra-performance liquid chromatography–tandem mass spectrometry method. Primary Outcome Measure The proliferative effects of estrogen metabolism were evaluated using 5-bromo-2′-deoxyuridine assays and CRC mouse xenograft studies. Results Human CRC exhibits dysregulated estrogen metabolism, favoring estradiol synthesis. The activity of STS, the fundamental enzyme that activates conjugated estrogens, is significantly (P < 0.001) elevated in human CRC compared with matched controls. STS overexpression accelerates CRC proliferation in in vitro and in vivo models, with STS inhibition an effective treatment. We defined a G-protein–coupled estrogen receptor (GPER) proproliferative pathway potentially through increased expression of connective tissue growth factor in CRC. Conclusion Human CRC favors estradiol synthesis to augment proliferation via GPER stimulation. Further research is required regarding whether estrogen replacement therapy should be used with caution in patients at high risk of developing CRC.

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SIRT4 is the molecular switch mediating cellular proliferation in colorectal cancer through GLS mediated activation of AKT/GSK3β/Cyclin D1 pathway

Carcinogenesis ◽

10.1093/carcin/bgaa134 ◽

2020 ◽

Author(s):

Ying Cui ◽

Yibing Bai ◽

Jiani Yang ◽

Yuanfei Yao ◽

Chunhui Zhang ◽

...

Keyword(s):

Colorectal Cancer ◽

Molecular Mechanisms ◽

Cellular Proliferation ◽

Colorectal Cancer Patient ◽

Migration And Invasion ◽

In Vivo Models ◽

Invasion And Migration ◽

Interactome Network

Abstract Mitochondria-localized sirtuin 4 (SIRT4) is associated with malignant phenotypes in colorectal cancer. However, the molecular mechanisms that drive SIRT4-mediated carcinogenesis are unclear. Initially, we confirmed expression of SIRT4 in colorectal cancer through public database and in colorectal cancer patient tissues using quantitative real-time reverse transcription PCR. We established HCT116 colorectal cells that overexpressed SIRT4 and HT29 cells were transfected with plasmids bearing a small interfering RNA siRNA construct to silence SIRT4. Assays to determine the malignant phenotypes (proliferation, invasion and migration) were performed. Xenograft in-vivo models were also constructed. A protein interactome network was built using differentially expressed proteins identified using the liquid chromatography/tandem mass spectrophotometry, the findings of which were confirmed using coimmunoprecipitation, western blotting, and phenotype rescue experiments. Decreased SIRT4 expression was associated with malignant phenotypes in vitro and in vivo. The ribosomal biogenesis pathway was enriched in the interactome network. SIRT4 suppression activated glutaminase, thereby initiating AKT activation. Our research provided novel insights into the molecular mechanisms underlying colorectal cancer, and identified that SIRT4 exerts its antitumor activity in colorectal cancer possibly dependent on glutaminase to inhibit proliferation, migration, and invasion via the AKT/GSK3β/CyclinD1 pathway.

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Fever supports CD8+ effector T cell responses by promoting mitochondrial translation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2023752118 ◽

2021 ◽

Vol 118 (25) ◽

pp. e2023752118

Author(s):

David O’Sullivan ◽

Michal A. Stanczak ◽

Matteo Villa ◽

Franziska M. Uhl ◽

Mauro Corrado ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Metabolic Activity ◽

Cell Metabolism ◽

Transcriptional Profiling ◽

Mitochondrial Translation ◽

In Vivo Models ◽

And Function

Fever can provide a survival advantage during infection. Metabolic processes are sensitive to environmental conditions, but the effect of fever on T cell metabolism is not well characterized. We show that in activated CD8+ T cells, exposure to febrile temperature (39 °C) augmented metabolic activity and T cell effector functions, despite having a limited effect on proliferation or activation marker expression. Transcriptional profiling revealed an up-regulation of mitochondrial pathways, which was consistent with increased mass and metabolism observed in T cells exposed to 39 °C. Through in vitro and in vivo models, we determined that mitochondrial translation is integral to the enhanced metabolic activity and function of CD8+ T cells exposed to febrile temperature. Transiently exposing donor lymphocytes to 39 °C prior to infusion in a myeloid leukemia mouse model conferred enhanced therapeutic efficacy, raising the possibility that exposure of T cells to febrile temperatures could have clinical potential.

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