Experimental study on expression level of IL-22 in lung adenocarcinoma and its mechanism in promoting lung adenocarcinoma metastasis
10.3760/cma.j.cn115355-20240428-00214
- VernacularTitle:肺腺癌IL-22表达水平及其促进肺腺癌转移机制的实验研究
- Author:
Weiran LIU
1
;
Xinyi WU
;
Changli WANG
;
Bin ZHANG
Author Information
1. 天津医科大学肿瘤医院麻醉科 国家恶性肿瘤临床医学研究中心 天津市"肿瘤防治"重点实验室 天津市恶性肿瘤临床医学研究中心，天津 300060
- Publication Type:Journal Article
- Keywords:
Lung neoplasms;
Adenocarcinoma;
Interleukin-22;
Neoplasm metastasis;
Tumor microenvironment
- From:
Cancer Research and Clinic
2025;37(3):177-185
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the expression of interleukin (IL)-22 in lung adenocarcinoma and its effect and possible mechanism for lung adenocarcinoma metastasis.Methods:The cancer tissues and paired adjacent normal tissues (>2 cm from the tumor edge) surgically removed from 27 lung adenocarcinoma patients in Tianjin Medical University Cancer Institute & Hospital from January to June 2023 were retrospectively collected. Flow cytometry was used to detect the expression levels of IL-22 in T cells of all tissues, and the expression levels of IL-22 in T cells were compared between cancer and adjacent tissues, as well as between lung cancer tissues of patients with and without lymph node metastasis. The cancer tissues and paired adjacent normal tissues were retrospectively collected from 6 patients with lung adenocarcinoma during the same period, and the expression level of IL-22 receptor IL-22RA1 in the tissues was detected by Western blotting. IL-22RA1 transcriptome data from cancer tissues of lung adenocarcinoma patients in 3 datasets in The Cancer Genome Atlas (TCGA) database and the Gene Expression Omnibus (GEO) database were collected. Using the R software survminer package to select the optimal critical value of IL-22RA1 that reflected the survival relationship, and patients were divided into high and low IL-22RA1 groups based on this. The survival package was used to draw the overall survival curve and log-rank test was performed for inter group comparison. Recombinant IL-22 was used to treat human lung adenocarcinoma A549 cells and mouse lung adenocarcinoma LLC cells, with cells not treated with IL-22 as controls; Transwell assay was used to detect the number of migrating cells in each group; Western blotting was used to detect the expression levels of ERK, AKT and STAT signaling pathways-related proteins, matrix metalloproteinase 9 (MMP-9) and epithelial cadherin (E-cad) in each group of cells. The expression levels of these proteins in A549 cells and LLC cells were also measured after the addition of STAT3 inhibitor C188-9, AKT inhibitor MK-2206 and ERK inhibitor SCH772984. A lung metastasis model of LLC cells was constructed using 10 C57BL/6 mice, the mice were randomly divided into the experimental group and the control group using simple randomization method. IL-22 neutralizing antibody (50 μg/mouse) and non-neutralizing control antibody (50 μg/mouse) were injected once every other day. On the 10th day, the mice were euthanized and dissected to count lung metastatic nodules. The metastatic lung tissue was stained with HE and the metastatic foci were counted. Flow cytometry was used to detect the proportion of CD4 + T cells and CD8 + T cells to immune cells in single cells prepared from metastatic lung tissue. Results:The flow cytometry analysis showed that the proportion of IL-22 + CD4 + T cells in T cells (labeled with CD3 and CD45) in 27 clinically collected lung adenocarcinoma tissues [ M ( Q1, Q3)] was higher than that in adjacent normal tissues [0.28% (0.04%, 1.00%) vs. 0.01% (0.00%, 0.25%)]. The proportion of IL-22 + CD4 + T cells in lung adenocarcinoma tissues of patients with metastasis (9 cases) was higher than that of patients without metastasis (18 cases) [1.06% (0.49%, 4.72%) vs. 0.15% (0.00%, 0.35%)], and the differences were statistically significant (both P < 0.01). Western blotting analysis showed that the relative expression level of IL-22RA1 protein in lung adenocarcinoma tissues was higher than that in adjacent normal tissues (1.03±0.25 vs. 0.35±0.10), and the difference was statistically significant ( P < 0.05). The overall survival of the IL-22RA1 low expression group in lung adenocarcinoma tissues was better than that of the IL-22RA1 high expression group in the TCGA database and GEO databases GSE42127, GSE29016 and GSE26939 datasets, and the differences were statistically significant (all P < 0.001). Transwell assay showed that A549 cells [(744±40) cells, (770±64) cells vs. (403±42) cells] and LLC cells [(167±39) cells, (246±80) cells vs. (31±5) cells] treated with 100 and 200 ng/ml IL-22 for 24 hours had fewer migration numbers than the control group, and the differences were statistically significant (both P < 0.01). Western blotting analysis showed that during treatment with 100 ng/ml recombinant IL-22 for 15-1 440 minutes, the levels of p-STAT3, p-ERK and p-AKT proteins in A549 and LLC cells were higher than those in the control group, while there was no difference in the levels of E-cad and MMP-9 proteins between the two groups. After the combined treatment of recombinant IL-22 and STAT3, AKT or ERK inhibitor, the corresponding levels of p-STAT3, p-AKT and p-ERK proteins in A549 and LLC cells were similar to those in cells without inhibitor and recombinant IL-22 treatment, but significantly lower than those in cells treated with recombinant IL-22 alone. In the dissected lung tissues of mice lung metastasis models, the experimental group had fewer metastatic lung nodules than the control group (2.3±0.6 vs. 7.0±2.0), and the difference was statistically significant ( t = 3.88, P = 0.018). In the morphological observation of lung metastasis tissues, the experimental group had fewer metastatic lesions than the control group (1.8±0.8 vs. 5.4±1.1), and the difference was statistically significant ( t = 5.69, P < 0.001). Flow cytometry analysis showed that the proportion of CD8 + T cells in immune cells in the lung tissues of mice in the experimental group (labeled with CD45) was higher than that in the control group [(27±5)% vs. (15±5)%], and the difference was statistically significant ( t = 3.01, P = 0.040). There was no statistically significant difference in the proportion of CD4 + T cells in immune cells between the two groups ( P > 0.05). Conclusions:The expression levels of IL-22 and its receptor IL-22RA1 in lung adenocarcinoma tissues are higher than those in adjacent normal tissues, and the high expression level of IL-22RA1 in cancer tissues may be associated with poor prognosis of patients; on the one hand, IL-22 may promote the migration of lung adenocarcinoma cells by activating the ERK, AKT and STAT3 signaling pathways, and on the other hand, it may promote lung adenocarcinoma metastasis by reducing CD8 + T cell infiltration in the immune microenvironment of lung adenocarcinoma.
