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

Identification of Serum Biomarkers to Monitor Therapeutic Response in Intestinal-Type Gastric Cancer

There are a limited number of clinically useful serum biomarkers to predict tumor onset or treatment response in gastric cancer (GC). For this reason, we explored the serum proteome of the gp130Y757F murine model of intestinal-type gastric cancer (IGC). We identified 30 proteins with significantly elevated expression in early gp130Y757F IGC and 12 proteins that were significantly elevated in late gp130Y757F IGC compared to age- and gender-matched wild-type mice. Within these signatures, there was an overlap of 10 proteins commonly elevated in both early- and late-stage disease. These results highlight the potential to identify serum biomarkers of disease stage. Since IGC in the gp130Y757F model can be reversed following therapeutic inhibition of Interleukin (IL)-11, we explored whether the protein signatures we identified could be used to monitor tumor regression. We compared two different therapeutic modalities and found 5 proteins to be uniquely differentially expressed between control animals and animals halfway through treatment, with 10 differentially expressed at the end of treatment. Our findings highlight the potential to identify reliable biomarkers to track IGC tumor regression in response to treatment

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

Stomach-specific activation of oncogenic KRAS and STAT3-dependent inflammation cooperatively promote gastric tumorigenesis in a preclinical model

About 5% to 10% of human gastric tumors harbor oncogenic mutations in the KRAS pathway, but their presence alone is often insufficient for inducing gastric tumorigenesis, suggesting a requirement for additional mutagenic events or microenvironmental stimuli, including inflammation. Assessing the contribution of such events in preclinical mouse models requires Cre recombinase–mediated conditional gene expression in stem or progenitor cells of normal and transformed gastric epithelium. We therefore constructed a bacterial artificial chromosome containing transgene (Tg), comprising the regulatory elements of the trefoil factor 1 (Tff1) gene and the tamoxifen-inducible Cre recombinase (CreERT2)–coding sequence. The resulting Tg(Tff1-CreERT2) mice were crossed with mice harboring conditional oncogenic mutations in Kras or Braf. The administration of tamoxifen to the resulting adult Tg(Tff1-CreERT2);KrasLSL-G12D/+ and Tg(Tff1-CreERT2);BrafLSL-V600E/+ mice resulted in gastric metaplasia, inflammation, and adenoma development, characterized by excessive STAT3 activity. To assess the contribution of STAT3 to the spontaneously developing gastric adenomas in gp130F/F mice, which carry a knockin mutation in the Il6 signal transducer (Il6st), we generated Tg(Tff1-CreERT2);Stat3fl/fl;gp130F/F mice that also harbor a conditional Stat3 knockout allele and found that tamoxifen administration conferred a significant reduction in their tumor burden. Conversely, excessive Kras activity in Tg(Tff1-CreERT2);KrasLSL-G12D/+;gp130F/F mice promoted more extensive gastric inflammation, metaplastic transformation, and tumorigenesis than observed in Tg(Tff1-CreERT2);KrasLSL-G12D/+ mice. Collectively, our findings demonstrate that advanced gastric tumorigenesis requires oncogenic KRAS or BRAF in concert with aberrant STAT3 activation in epithelial precursor cells of the glandular stomach, providing a new conditional model of gastric cancer in which to investigate candidate therapeutic targets and treatment strategies

Inhibition of Hematopoietic Cell Kinase Activity Suppresses Myeloid Cell-Mediated Colon Cancer Progression

Aberrant activation of the SRC family kinase hematopoietic cell kinase (HCK) triggers hematological malignancies as a tumor cell-intrinsic oncogene. Here we find that high HCK levels correlate with reduced survival of colorectal cancer patients. Likewise, increased Hck activity in mice promotes the growth of endogenous colonic malignancies and of human colorectal cancer cell xenografts. Furthermore, tumor-associated macrophages of the corresponding tumors show a pronounced alternatively activated endotype, which occurs independently of mature lymphocytes or of Stat6-dependent Th2 cytokine signaling. Accordingly, pharmacological inhibition or genetic reduction of Hck activity suppresses alternative activation of tumor-associated macrophages and the growth of colon cancer xenografts. Thus, Hck may serve as a promising therapeutic target for solid malignancies

mTORC1 inhibition restricts infammation-associated gastrointestinal tumorigenesis in mice

10.1172/JCI65086Journal of Clinical Investigation1232767-781JCIN

MACROD2 haploinsufficiency impairs catalytic activity of PARP1 and promotes chromosome instability and growth of intestinal tumors

ADP-ribosylation is an important post-translational protein modification that regulates diverse biological processes, controlled by dedicated transferases and hydrolases. Here we show that frequent deletions (~30%) of the MACROD2 mono-ADP-ribosylhydrolase locus in human colorectal cancer (CRC) cause impaired PARP1 transferase activity in a gene dosage-dependent manner. MACROD2 haploinsufficiency alters DNA repair and sensitivity to DNA damage, and results in chromosome instability. Heterozygous and homozygous depletion of Macrod2 enhances intestinal tumorigenesis in ApcMin/+ mice and the growth of human CRC xenografts. MACROD2 deletion in sporadic CRC is associated with the extent of chromosome instability, independent of clinical parameters and other known genetic drivers. We conclude that MACROD2 acts as a haploinsufficient tumor suppressor, with loss of function promoting chromosome instability thereby driving cancer evolution