Type 2 Innate Lymphoid Cells Protect against Colorectal Cancer Progression and Predict Improved Patient Survival.

Chronic inflammation of the gastrointestinal (GI) tract contributes to colorectal cancer (CRC) progression. While the role of adaptive T cells in CRC is now well established, the role of innate immune cells, specifically innate lymphoid cells (ILCs), is not well understood. To define the role of ILCs in CRC we employed complementary heterotopic and chemically-induced CRC mouse models. We discovered that ILCs were abundant in CRC tumours and contributed to anti-tumour immunity. We focused on ILC2 and showed that ILC2-deficient mice developed a higher tumour burden compared with littermate wild-type controls. We generated an ILC2 gene signature and using machine learning models revealed that CRC patients with a high intratumor ILC2 gene signature had a favourable clinical prognosis. Collectively, our results highlight a critical role for ILC2 in CRC, suggesting a potential new avenue to improve clinical outcomes through ILC2-agonist based therapeutic approaches

Interleukin-11 Is the Dominant IL-6 Family Cytokine during Gastrointestinal Tumorigenesis and Can Be Targeted Therapeutically

SummaryAmong the cytokines linked to inflammation-associated cancer, interleukin (IL)-6 drives many of the cancer “hallmarks” through downstream activation of the gp130/STAT3 signaling pathway. However, we show that the related cytokine IL-11 has a stronger correlation with elevated STAT3 activation in human gastrointestinal cancers. Using genetic mouse models, we reveal that IL-11 has a more prominent role compared to IL-6 during the progression of sporadic and inflammation-associated colon and gastric cancers. Accordingly, in these models and in human tumor cell line xenograft models, pharmacologic inhibition of IL-11 signaling alleviated STAT3 activation, suppressed tumor cell proliferation, and reduced the invasive capacity and growth of tumors. Our results identify IL-11 signaling as a potential therapeutic target for the treatment of gastrointestinal cancers

The Diverse Applications of Pancreatic Ductal Adenocarcinoma Organoids

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal solid malignancies. While immortalized cancer cell lines and genetically engineered murine models have increased our understanding of PDAC tumorigenesis, they do not recapitulate inter- and intra-patient heterogeneity. PDAC patient derived organoid (PDO) biobanks have overcome this hurdle, and provide an opportunity for the high throughput screening of potential new therapies. This review provides a summary of the PDAC PDO biobanks established to date, and discusses how they have advanced our understanding of PDAC biology. Looking forward, the development of coculturing techniques for specific immune or stromal cell populations will enable a better understanding of the crosstalk that occurs within the tumor microenvironment, and the impact of this crosstalk on treatment response

Loss of NFKB1 Results in Expression of Tumor Necrosis Factor and Activation of STAT1 to Promote Gastric Tumorigenesis in Mice.

Activity of NFkB transcription factors and signaling via STAT are frequently altered in gastric cancer cells. Mice lacking NFKB1 (Nfkb1 mice) develop invasive gastric cancer and their gastric tissues have increased levels of cytokines, such as interleukin (IL)6, IL22, IL11, and tumor necrosis factor (TNF), as well as increased activation of signal transducer and activator of transcription 1 (STAT1). We investigated whether these cytokines were required for STAT1 activation in gastric tissues of mice and critical for gastric tumorigenesis. We crossed Nfkb1 mice with Il6, Il22, Il11Rα and Tnf mice. Stomach tissues from compound mutant mice were analyzed by histology, immunoblotting and RNA sequencing. Lymphoid, myeloid and epithelial cells were isolated from stomachs and the levels of cytokines were determined by flow cytometric analysis. Nfkb1 mice developed gastritis, oxyntic atrophy, gastric dysplasia and invasive tumors, whereas Nfkb1Stat1 mice did not, even when followed for as long as 2 years. The levels of Il6, Il11, and Il22 and Tnf mRNA were increased in the body and antrum of the stomachs from Nfkb1 mice, from 6 months of age. However, Nfkb1Il6, Nfkb1Il22 and Nfkb1Il11Rα mice still developed gastric tumors, although the absence of IL11 receptor (IL11R) significantly reduced development of invasive gastric tumors. Stomachs from Nfkb1Tnf mice exhibited significantly less gastritis and oxyntic atrophy and fewer tumors than Nfkb1 mice. This correlated with reduced activation of STAT1 and STAT3 and fewer numbers of T cells and B cells infiltrating the gastric body. Loss of STAT1 significantly reduced expression of PD-L1 on epithelial and myeloid (CD11b) cells in the gastric mucosa of Nfkb1 mice, indeed to the levels observed on the corresponding cells from wild-type mice. In studies of gastric tumor development in knockout mice, we found that loss of NFKB1 causes increased expression of TNF in the stomach and thereby drives activation of STAT1, resulting in an inflammatory immune response and the development of gastric cancer. IL11R appears to be required for the progression of gastric tumors to the invasive stage. These findings suggest that inhibitors of TNF, and possibly also inhibitors of IL11/IL11Rα, might be useful in the treatment of gastric cancer

Repurposing the selective estrogen receptor modulator bazedoxifene to suppress gastrointestinal cancer growth

Abstract Excessive signaling through gp130, the shared receptor for the interleukin (IL)6 family of cytokines, is a common hallmark in solid malignancies and promotes their progression. Here, we established the in vivo utility of bazedoxifene, a steroid analog clinically approved for the treatment of osteoporosis, to suppress gp130‐dependent tumor growth of the gastrointestinal epithelium. Bazedoxifene administration reduced gastric tumor burden in gp130Y757F mice, where tumors arise exclusively through excessive gp130/STAT3 signaling in response to the IL6 family cytokine IL11. Likewise, in mouse models of sporadic colon and intestinal cancers, which arise from oncogenic mutations in the tumor suppressor gene Apc and the associated β‐catenin/canonical WNT pathway, bazedoxifene treatment reduces tumor burden. Consistent with the proposed orthogonal tumor‐promoting activity of IL11‐dependent gp130/STAT3 signaling, tumors of bazedoxifene‐treated Apc‐mutant mice retain excessive nuclear accumulation of β‐catenin and aberrant WNT pathway activation. Likewise, bazedoxifene treatment of human colon cancer cells harboring mutant APC did not reduce aberrant canonical WNT signaling, but suppressed IL11‐dependent STAT3 signaling. Our findings provide compelling proof of concept to support the repurposing of bazedoxifene for the treatment of gastrointestinal cancers in which IL11 plays a tumor‐promoting role

Elevated Dnmt3a activity promotes polyposis in ApcMin mice by relaxing extracellular restraints on Wnt signaling

Background & Aims: Aberrant DNA methylation is a common early event in neoplasia, but it is unclear how this relates to dysregulation of DNA (cytosine-5) methyltransferases (Dnmts). Here we use knock-in transgenic mice to investigate the consequences of intestinal epithelium-specific overexpression of de novo Dnmt3a. Methods: A novel gene targeting strategy, based on the intestinal epithelium-specific, uniform expression of the A33 glycoprotein, is employed to restrict Dnmt3a overexpression in homozygous A33 mutant mice. Results: A33 mice infrequently develop spontaneous intestinal polyps. However, when genetically challenged, tumor multiplicity in A33;Apc compound mice is 3-fold higher than in Apc mice. Although we observe a requirement for spontaneous loss of heterozygosity of the adenomatous polyposis coli (Apc) gene to trigger tumorigenesis in Apc mice, lesions in A33;Apc mice frequently retain the wild-type Apc allele. However, epithelia from normal mucosa and polyps of A33;Apc mice show hypermethylation-mediated transcriptional silencing of the Wnt antagonists Sfrp5, and to a lesser extent, Sfrp1 and increased nuclear β-catenin alongside activation of the Wnt-target gene Axin2/Conductin. Conversely, enforced Sfrp5 expression suppresses canonical Wnt-signaling more effectively in wild-type than in Apc cells. Conclusions: Aberrant activation of the canonical Wnt pathway, either by mono-allelic Apc loss or transcriptional silencing of Sfrp5 is largely insufficient to promote polyposis, but epistatic interactions between these genetic and epigenetic events enables initiation and promotion of disease. This mechanism is likely to play a role in human colorectal cancer, because we also show that elevated DNMT3A expression coincides with repressed SFRP5 and enhanced AXIN2/CONDUCTIN expression in paired patient biopsies

Inhibition of the SRC Kinase HCK Impairs STAT3-Dependent Gastric Tumor Growth in Mice

Persistent activation of the latent transcription factor STAT3 is observed in gastric tumor epithelial and immune cells and is associated with a poor patient prognosis. Although targeting STAT3-activating upstream kinases offers therapeutically viable targets with limited specificity, direct inhibition of STAT3 remains challenging. Here we provide functional evidence that myeloid-specific hematopoietic cell kinase (HCK) activity can drive STAT3-dependent epithelial tumor growth in mice and is associated with alternative macrophage activation alongside matrix remodeling and tumor cell invasion. Accordingly, genetic reduction of HCK expression in bone marrow-derived cells or systemic pharmacologic inhibition of HCK activity suppresses alternative macrophage polarization and epithelial STAT3 activation, and impairs tumor growth. These data validate HCK as a molecular target for the treatment of human solid tumors harboring excessive STAT3 activity