IL-22 promotes the proliferation of cancer cells in smoking colorectal cancer patients

Cigarettes and waterpipe use and risk of colorectal cancer in Iran: the IROPICAN study

We aimed to investigate the association between cigarettes and waterpipe use and colorectal cancer (CRC) in an Iranian population. We analyzed data from a multicenter hospital-based case-control study in Iran (IROPICAN). Data on tobacco smoking, including cigarettes, and waterpipe smoking, were collected in detail. Multivariate logistic regressions estimated the odds ratios (ORs) and 95% confidence intervals (CIs) for the association between cigarette and waterpipe smoking and CRC, accounting for confounders including age, sex, socioeconomic status, opium use, marital status, family history of cancer, red meat, fiber, body shape at age 15 and perceived physical workload, and each other of the two exposures. The study population consisted of 3215 controls and 848 cases, including 455 colon and 393 rectum cancers. We found no association between CRC and cigarette smoking (OR, 0.8; 95% CI, 0.6-1.0) or waterpipe smoking (OR, 1.1; 95% CI, 0.9-1.5). Analysis by categories of cigarette pack-year and frequency of waterpipe smoking (head-year) did not show associations. We observed an inverse association between colon cancer and cigarette smoking (OR, 0.6; 95% CI, 0.5-0.9). There was, however, no significant association by pack-year categories. Cigarette and waterpipe smoking was not associated with CRC in the Iranian population. Further studies are needed to better understand the role of waterpipe on CRC.

Smoking as a risk factor for colorectal neoplasms in young individuals? A systematic meta-analysis

BACKGROUND AND AIMS

Early-onset colorectal neoplasms (EoCRN) include both benign and malign colorectal tumors, which occur before the age of 50. The incidence of EoCRN is rising worldwide. Tobacco smoking has previously been proven to be related to the development of various tumor types. However, its relationship with EoCRN is not clearly defined. Hence, we carried out a systematic review and a meta-analysis to evaluate the relationship between smoking status and the risk of EoCRN.

METHODS

A systematic search of PubMed, EMBASE, and Web of Science up to September 7, 2022, was performed for studies that evaluated the association of smoking status with EoCRN. The quality of the case-control study was evaluated with the Newcastle‒Ottawa Scale. The quality of the cross-sectional studies was evaluated with the American Health Care Research and Quality checklist. Fixed-effects models were used to pool odds ratios (ORs) to evaluate the relationship between the risk of developing EoCRN and smoking status. The meta-analyses were performed with Review Manager version 5.4, and funnel plots and publication bias tests were produced by STATA software.

RESULTS

A total of six studies were included in this meta-analysis. After pooling the results of these six studies, we found that current smokers carry a relatively high risk of developing EoCRN (OR, 1.33; 95% confidence interval [CI], 1.17-1.52) compared to never-smokers. Ex-smokers were not at a significantly increased risk for developing EoCRN (OR, 1.00; 95% CI, 0.86-1.18).

DISCUSSION

Smoking behavior is significantly associated with an increased risk for developing EoCRN and might be one of the reasons for the increasing incidence. Ex-smokers who quit are not at significant risk of developing EoCRN.

Rationalizing heptadecaphobia: TH 17 cells and associated cytokines in cancer and metastasis

Cancer is one of the leading causes of death worldwide. When cancer patients are diagnosed with metastasis, meaning that the primary tumor has spread to at least one different site, their life expectancy decreases dramatically. In the past decade, the immune system´s role in fighting cancer and metastasis has been studied extensively. Importantly, immune cells and inflammatory reactions generate potent antitumor responses but also contribute to tumor development. However, the molecular and cellular mechanisms underlying this dichotomic interaction between the immune system and cancer are still poorly understood. Recently, a spotlight has been cast on the distinct subsets of immune cells and their derived cytokines since evidence has implicated their crucial impact on cancer development. T helper 17 cell (TH 17) cells, which express the master transcriptional factor Retinoic acid-receptor-related orphan receptor gamma t, are among these critical cell subsets and are defined by their production of type 3 cytokines, such as IL-17A, IL-17F, and IL-22. Depending on the tumor microenvironment, these cytokines can also be produced by other immune cell sources, such as T cytotoxic 17 cell, innate lymphoid cells, NKT cells, or γδ T cells. To date, a lot of data have been collected describing the divergent functions of IL-17A, IL-17F, and IL-22 in malignancies. In this comprehensive review, we discuss the role of these TH 17- and non-TH 17-derived type 3 cytokines in different tumor entities. Furthermore, we will provide a structured insight into the strict regulation and subsequent downstream mechanisms of these cytokines in cancer and metastasis.

Infiltration by IL22-Producing T Cells Promotes Neutrophil Recruitment and Predicts Favorable Clinical Outcome in Human Colorectal Cancer

Immune cell infiltration in colorectal cancer effectively predicts clinical outcome. IL22, produced by immune cells, plays an important role in inflammatory bowel disease, but its relevance in colorectal cancer remains unclear. Here, we addressed the prognostic significance of IL22+ cell infiltration in colorectal cancer and its effects on the composition of tumor microenvironment. Tissue microarrays (TMA) were stained with an IL22-specific mAb, and positive immune cells were counted by expert pathologists. Results were correlated with clinicopathologic data and overall survival (OS). Phenotypes of IL22-producing cells were assessed by flow cytometry on cell suspensions from digested specimens. Chemokine production was evaluated in vitro upon colorectal cancer cell exposure to IL22, and culture supernatants were used to assess neutrophil migration in vitro Evaluation of a testing (n = 425) and a validation TMA (n = 89) revealed that high numbers of IL22 tumor-infiltrating immune cells were associated with improved OS in colorectal cancer. Ex vivo analysis indicated that IL22 was produced by CD4+ and CD8+ polyfunctional T cells, which also produced IL17 and IFNγ. Exposure of colorectal cancer cells to IL22 promoted the release of the neutrophil-recruiting chemokines CXCL1, CXCL2, and CXCL3 and enhanced neutrophil migration in vitro Combined survival analysis revealed that the favorable prognostic significance of IL22 in colorectal cancer relied on the presence of neutrophils and was enhanced by T-cell infiltration. Altogether, colorectal cancer-infiltrating IL22-producing T cells promoted a favorable clinical outcome by recruiting beneficial neutrophils capable of enhancing T-cell responses.

Interleukin-22 enhances chemoresistance of lung adenocarcinoma cells to paclitaxel

The chemoresistance of tumors is the main barrier to cancer treatment. Interleukin-22 (IL-22) plays an important role in the chemoresistance of multi-cancers; however, the roles of IL-22 in the paclitaxel resistance of lung adenocarcinoma cells remain to be investigated. The present study aims to investigate the potential mechanisms of IL-22 enhancing the chemoresistance of lung adenocarcinoma cells to paclitaxel. We cultured A549, H358, and A549/PTX cell lines. qRT-PCR and western blot assays were performed to examine the mRNA and/or protein levels of IL-22 in A549, A549/PTX, H358, and H358/PTX. Moreover, cells were transfected with IL-22 siRNA1, IL-22 siRNA2, and siRNA NC, and treated with paclitaxel, and the proliferation rate of lung adenocarcinoma cells was evaluated by MTT assay. Flow cytometry was conducted to determine the apoptosis rate of lung adenocarcinoma cells. The results showed that the expression of IL-22 in lung adenocarcinoma tissues was higher than that in normal tissues, and the expression of IL-22 was higher in A549/PTX and H358/PTX compared with A549 and H358 cells. Meanwhile, the expression of IL-22 was strongly correlated with smoking history and TMN stage, as well. Furthermore, IL-22 siRNA inhibited the proliferation and promoted the apoptosis of A549/PTX and H358/PTX cells, and IL-22 siRNA also suppressed the expression levels of AKT and Bcl-2 and increased the expression levels of Bax and cleaved caspase 3. To sum up, IL-22 may mediate the chemosensitivity of lung adenocarcinoma cells to paclitaxel through inhibiting the AKT signaling pathways.

A catch-22: Interleukin-22 and cancer

Barrier surfaces of multicellular organisms are in constant contact with the environment and infractions to the integrity of epithelial surfaces is likely a frequent event. Interestingly, components of the immune system, that can be activated by environmental compounds such as the microbiota or nutrients, are interspersed among epithelial cells or directly underlie the epithelium. It is now appreciated that immune cells continuously receive and integrate signals from the environment. Curiously, such continuous reception of stimulation does not normally trigger an inflammatory response but mediators produced by immune cells in response to such signals seem to rather promote barrier integrity and repair. The molecular mediators involved in this process are poorly understood. In recent years, the cytokine interleukin-22, produced mainly by group 3 innate lymphoid cells (ILCs), has been studied as a paradigm for how immune cells can control various aspects of epithelial cell function because expression of its receptor is restricted to non-hematopoietic cells. We will summarize here the diverse roles of IL-22 for the malignant transformation of epithelial cells, for tumor growth, wound healing and tissue repair. Furthermore, we will discuss IL-22 as a potential therapeutic target.

Interleukin-22 in human inflammatory diseases and viral infections

Interleukin-22 (IL22) is one of the members of IL10 family. Elevated levels of this cytokine can be seen in diseases caused by T lymphocytes, such as Psoriasis, Rheumatoid arthritis, interstitial lung diseases. IL22 is produced by different cells in both innate and acquired immunities. Different types of T cells are able to produce IL22, but the major IL22-producing T-cell is the TCD4. TH22 cell is a new line of TCD4 cells, which differentiated from naive T cells in the presence of TNFα and IL6; 50% of peripheral blood IL22 is produced by these cells. IL22 has important functions in host defense at mucosal surfaces as well as in tissue repair. In this review, we assess the current understanding of this cytokine and focus on the possible roles of IL-22 in autoimmune diseases.