Cytokine-Induced Modulation of Colorectal Cancer

Antitumor Effects of Epidrug/IFNα Combination Driven by Modulated Gene Signatures in Both Colorectal Cancer and Dendritic Cells

Colorectal cancer results from the progressive accumulation of genetic and epigenetic alterations. IFN signaling defects play an important role in the carcinogenesis process, in which the inability of IFN transcription regulatory factors (IRF) to access regulatory sequences in IFN-stimulated genes (ISG) in tumors and in immune cells may be pivotal. We reported that low-dose combination of two FDA-approved epidrugs, azacytidine (A) and romidepsin (R), with IFNα2 (ARI) hampers the aggressiveness of both colorectal cancer metastatic and stem cells in vivo and triggers immunogenic cell death signals that stimulate dendritic cell (DC) function. Here, we investigated the molecular signals induced by ARI treatment and found that this drug combination increased the accessibility to regulatory sequences of ISGs and IRFs that were epigenetically silenced in both colorectal cancer cells and DCs. Likewise, specific ARI-induced histone methylation and acetylation changes marked epigenetically affected ISG promoters in both metastatic cancer cells and DCs. Analysis by ChIP-seq confirmed such ARI-induced epigenetically regulated IFN signature. The activation of this signal endowed DCs with a marked migratory capability. Our results establish a direct correlation between reexpression of silenced ISGs by epigenetic control and ARI anticancer activity and provide new knowledge for the development of innovative combined therapeutic strategies for colorectal cancer. Cancer Immunol Res; 5(7); 604-16. ©2017 AACR.

Interleukin 2 and interleukin 10 function synergistically to promote CD8+ T cell cytotoxicity, which is suppressed by regulatory T cells in breast cancer

The precise role of interleukin (IL)-10 in breast cancer is not clear. Previous studies suggested a tumor-promoting role of IL-10 in breast cancer, whereas recent discoveries that IL-10 activated and expanded tumor-resident CD8+ T cells challenged the traditional view. Here, we investigated the role of IL-10 in HLA-A2-positive breast cancer patients with Grade III, Stage IIA or IIB in-situ and invasive ductal carcinoma, and compared it with that of IL-2, the canonical CD8+ T cell growth factor. We first observed that breast cancer patients presented higher serum levels of IL-2 and IL-10 than healthy controls. Upon prolonged TCR stimulation, peripheral blood CD8+ T cells from breast cancer patients tended to undergo apoptosis, which could be prevented by the addition of IL-2 and/or IL-10. The cytotoxicity of TCR-activated CD8+ T cells was also enhanced by exogenous IL-2 and/or IL-10. Interestingly, IL-2 and IL-10 demonstrated synergistic effects, since the enhancement in CD8+ T cell function when both cytokines were added was greater than the sum of the improvements mediated by each individual cytokine. IL-10 by itself could not promote the proliferation of CD8+ T cells but could significantly enhance IL-2-mediated promotion of CD8+ T cell proliferation. In addition, the cytotoxicity of tumor-infiltrating CD8+ T cells in breast tumor was elevated when both IL-2 and IL-10 were present but not when either one was absent. This synergistic effect was stopped by CD4+CD25+ regulatory T cells (Treg), which depleted IL-2 in a cell number-dependent manner. Together, these results demonstrated that IL-2 and IL-10 could work synergistically to improve the survival, proliferation, and cytotoxicity of activated CD8+ T cells, an effect suppressible by CD4+CD25+ Treg cells.

Cancer Cytokines and the Relevance of 3D Cultures for Studying Those Implicated in Human Cancers

Cancers are complex conditions and involve several factors for oncogenesis and progression. Of the various factors influencing the physiology of cancers, cytokines are known to play significant roles as mediators of functions. Intricate cytokine networks have been identified in cancers and interest in cytokines associated with cancers has been gaining ground. Of late, some of these cytokines are even identified as potential targets for cancer therapy apart from a few others such as IL-6 being identified as markers for disease prognosis. Of the major contributors to cancer research, cancer cell lines occupy the top slot as the most widely used material in vitro. In vitro cell cultures have seen significant evolution by the introduction of 3-dimensional (3D) culture systems. 3D cell cultures are now widely accepted as excellent material for cancer research which surpass the traditional monolayer cultures. Cancer research has benefited from 3D cell cultures for understanding the various hallmarks of cancers. However, the potential of these culture systems are still unexploited for cancer cytokine research compared to the other aspects of cancers such as gene expression changes, drug-induced toxicity, morphology, angiogenesis, and invasion. Considering the importance of cancer cytokines, 3D cell cultures can be better utilized in understanding their roles and functions. Some of the possibilities where 3D cell cultures can contribute to cancer cytokine research arise from the distinct morphology of the tumor spheroids, the extracellular matrix (ECM), and the spontaneous occurrence of nutrient and oxygen gradients. Also, the 3D culture models enable one to co-culture different types of cells as a simulation of in vivo conditions, enhancing their utility to study cancer cytokines. We review here the cancer associated cytokines and the contributions of 3D cancer cell cultures for studying cancer cytokines. J. Cell. Biochem. 118: 2544-2558, 2017. © 2017 Wiley Periodicals, Inc.

A novel model of colitis-associated cancer in SAMP1/YitFc mice with Crohn's disease-like ileitis

Patients with inflammatory bowel disease (IBD) are at increased risk for developing colorectal cancer. Evidence suggests that colonic dysplasia and colitis-associated cancer (CAC) are often linked to repeated cycles of epithelial cell injury and repair in the context of chronic production of inflammatory cytokines. Several mouse models of CAC have been proposed, including chemical induction through exposure to dextran sulfate sodium (DSS) with the genotoxic agents azoxymethane (AOM), 1,2-dymethylhydrazine (DHM) or targeted genetic mutations. However, such models are usually performed on healthy animals that usually lack the underlying genetic predisposition, immunological dysfunction and dysbiosis characteristic of IBD. We have previously shown that inbred SAMP1/YitFc (SAMP) mice develop a progressive Crohn’s disease (CD)-like ileitis in the absence of spontaneous colitis. We hypothesize that SAMP mice may be more susceptible to colonic tumorigenesis due to their predisposition to IBD. To test this hypothesis, we administered AOM/DSS to IBD-prone SAMP and their non-inflamed parental control strain, AKR mice. Our results showed that AOM/DSS treatment enhanced the susceptibility of colitis in SAMP compared to AKR mice, as assessed by endoscopic and histologic inflammatory scores, daily weight loss and disease activity index (DAI), during and after DSS administration. SAMP mice also showed increased colonic tumorigenesis, resulting in the occurrence of intramucosal carcinoma and a higher incidence of high-grade dysplasia and tumor burden. These phenomena occurred even in the absence of AOM and only upon repeated cycles of DSS. Taken together, our data demonstrate a heightened susceptibility to colonic inflammation and tumorigenesis in AOM/DSS-treated SAMP mice with CD-like ileitis. This novel model represents a useful tool to investigate relevant mechanisms of CAC, as well as for pre-clinical testing of potential IBD and colon cancer therapeutics.

Fatty acid and mineral receptors as drug targets for gastrointestinal disorders

Nutrient-sensing receptors, including fatty acid receptors (FFA1–FFA4), Ca2+-sensing receptors and Zn2+-sensing receptors, are involved in several biological processes. These receptors are abundantly expressed in the GI tract, where they have been shown to play crucial roles in regulating GI function. This review provides an overview of the GI functions of fatty acid and mineral receptors, including the regulation of gastric and enteroendocrine functions, GI motility, ion transport and cell growth. Recently, several lines of evidence have implicated these receptors as promising therapeutic targets for the treatment of GI disorders, for example, inflammatory bowel disease, colorectal cancer, metabolic syndrome and diarrheal diseases. A future perspective on drug discovery research targeting these receptors is discussed.

The Role of IL-33-Dependent Inflammation in the Tumor Microenvironment

There is compelling evidence that inflammation contributes to tumorigenesis. Inflammatory mediators within the tumor microenvironment can either promote an antitumor immune response or support tumor pathogenesis. Therefore, it is critical to determine the relative contribution of tumor-associated inflammatory pathways to cancer development. Interleukin-33 (IL-33) is a member of the IL-1 family of cytokines that is released upon tissue stress or damage to operate as an alarmin. IL-33 has been primarily implicated in the induction of type-2 immune responses. However, recent findings have shown a role of IL-33 in several cancers where it may exert multiple functions. In this review, we will present the current knowledge on the role of IL-33 in the microenvironment of different tumors. We will highlight which cells produce and which cells are activated by IL-33 in cancer. Furthermore, we will explain how IL-33 modulates the tumor-associated inflammatory microenvironment to restrain or promote tumorigenesis. Finally, we will discuss the issues to be addressed first before potentially targeting the IL-33 pathway for cancer therapy.

Sprout S, Phillips D, Oliver PM. Ndfip1 restricts Th17 cell potency by limiting lineage stability and proinflammatory cytokine production

While Th17 cells can protect against colonization by pathogenic organisms, they also have the potential to become pathogenic and promote autoimmune and inflammatory diseases. Mechanisms that control their pathogenic potential remain poorly understood. Here we show that Ndfip1, a co-activator of the E3 ubiquitin ligase Itch, restricts the frequency and pathogenicity of Th17 cells. Mice lacking Ndfip1 have increased numbers of Th17 cells, and this increase is cell intrinsic. We found that Ndfip1 restricts production of the proinflammatory cytokines in Th17 cells. Increased cytokine production correlated with reduced degradation and accumulation of RORγT. When transferred in vivo, Th17 cells lacking Ndfip1 were more likely to maintain their ability to make IL-17, were more potent proinflammatory cytokine producers, and were powerful inducers of colitis. Together our data support an essential role for Ndfip1 in degrading RORγT and suppressing Th17 lineage stability, proinflammatory cytokine production, and pathogenicity.

Colon cancer metastasis to the mandibular gingiva with partial occult squamous differentiation: A case report and literature review

Metastasis is the primary cause of death among patients with colon cancer. However, the number of available studies regarding oral cavity metastases from colon cancer is currently limited. We herein report an unusual case of a 60-year-old male patient who developed an oral cavity metastasis from colon cancer. A total of 12 clinical case studies reporting colon cancer metastases to the mandibular gingival region were also reviewed, with the aim to elucidate the clinical and pathological characteristics of this disease entity in order to improve clinical diagnosis and treatment. It was demonstrated that patients with oral cavity metastases from colon cancer were predominantly in the sixth or seventh decades of life. The mandible was the main site of metastatic tumors to the oral cavity, while the occurrence of gingival metastases was comparatively rare. Moreover, the diagnoses of an oral metastatic tumor and primary colon cancer were often synchronous and were frequently accompanied with metastases to other organs. Several key aspects were suggested that should be accounted for when diagnosing colon cancer patients, including focusing attention to oral symptoms when examining cancer patients, utilizing a multidisciplinary approach for differential diagnosis and utilizing postoperative pathological examination to accurately diagnose the type of tumor and optimize the efficacy of treatment.