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CCL21/CCR7 prevents apoptosis via the ERK pathway in human non-small cell lung cancer cells.

ABSTRACT: Previously, we confirmed that C-C chemokine receptor 7 (CCR7) promotes cell proliferation via the extracellular signal-regulated kinase (ERK) pathway, but its role in apoptosis of non-small cell lung cancer (NSCLC) cell lines remains unknown. A549 and H460 cells of NSCLC were used to examine the effect of CCL21/CCR7 on apoptosis using flow cytometry. The results showed that activation of CCR7 by its specific ligand, exogenous chemokine ligand 21 (CCL21), was associated with a significant decline in the percent of apoptosis. Western blot and real-time PCR assays indicated that activation of CCR7 significantly caused upregulation of anti-apoptotic bcl-2 and downregulation of pro-apoptotic bax and caspase-3, but not p53, at both protein and mRNA levels. CCR7 small interfering RNA significantly attenuated these effects of exogenous CCL21. Besides, PD98059, a selective inhibitor of MEK that disrupts the activation of downstream ERK, significantly abolished these effects of CCL21/CCR7. Coimmunoprecipitation further confirmed that there was an interaction between p-ERK and bcl-2, bax, or caspase-3, particularly in the presence of CCL21. These results strongly suggest that CCL21/CCR7 prevents apoptosis by upregulating the expression of bcl-2 and by downregulating the expression of bax and caspase-3 potentially via the ERK pathway in A549 and H460 cells of NSCLC.

SUBMITTER: Xu Y

PROVIDER: S-EPMC3306387 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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CCL21/CCR7 prevents apoptosis via the ERK pathway in human non-small cell lung cancer cells.

Xu Ying Y Liu Lifeng L Qiu Xueshan X Liu Zihui Z Li Haiying H Li Zixuan Z Luo Wenting W Wang Enhua E

PloS one 20120316 3

Previously, we confirmed that C-C chemokine receptor 7 (CCR7) promotes cell proliferation via the extracellular signal-regulated kinase (ERK) pathway, but its role in apoptosis of non-small cell lung cancer (NSCLC) cell lines remains unknown. A549 and H460 cells of NSCLC were used to examine the effect of CCL21/CCR7 on apoptosis using flow cytometry. The results showed that activation of CCR7 by its specific ligand, exogenous chemokine ligand 21 (CCL21), was associated with a significant decline ...[more]

PMID: 22438908

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Project description:BackgroundTumor metastasis is driven by malignant cells and stromal cell components of the tumor microenvironment. Cancer stem cells (CSCs) are thought to be responsible for metastasis by altering the tumor microenvironment. Epithelial-mesenchymal transition (EMT) processes contribute to specific stages of the metastatic cascade, promoted by cytokines and chemokines secreted by stromal cell components in the tumor microenvironment. C-C chemokine receptor 7 (CCR7) interacts with its ligand, chemokine ligand 21(CCL21), to mediate metastasis in some cancer cells lines. This study investigated the role of CCL21/CCR7 in promoting EMT and metastasis of cluster of differentiation 133+ (CD133+) pancreatic cancer stem-like cells.MethodsPanc-1, AsPC-1, and MIA PaCa-2 pancreatic cancer cells were selected because of their aggressive invasive potentials. CCR7 expression levels were examined in total, CD133+ and CD133- cell fractions by Immunofluorescence analysis and real time-quantitative polymerase chain reaction (RT-qPCR). The role of CCL21/CCR7 in mediating metastasis and survival of CD133+ pancreatic cancer stem-like cells was detected by Transwell assays and flow cytometry, respectively. EMT and lymph node metastasis related markers (E-cadherin, N- cadherin, LYVE-1) were analyzed by western blot. CCR7 expression levels were analyzed by immunohistochemical staining and RT-qPCR in resected tumor tissues, metastatic lymph nodes, normal lymph nodes and adjacent normal tissues from patients with pancreatic carcinoma.ResultsCCR7 expression was significantly increased in CD133+ pancreatic cancer stem-like cells, resected pancreatic cancer tissues, and metastatic lymph nodes, compared with CD133- cancer cells, adjacent normal tissues and normal lymph nodes, respectively. CCL21/CCR7 promoted metastasis and survival of CD133+ pancreatic cancer stem-like cells and regulated CD133+ pancreatic cancer stem-like cells metastasis by modulating EMT and Erk/NF-κB pathway.ConclusionsThese results indicate a specific role for CCL21/CCR7 in promoting EMT and metastasis in CD133+ pancreatic cancer stem-like cells. Furthermore the data also indicated the potential importance of developing therapeutic strategies targeting cancer stem-like cells and CCL21/CCR7 for reducing metastasis.

Project description:Transmembrane protein 229A (TMEM229A) is a member of the TMEM family that plays an important role in tooth differentiation and development. However, the expression level and biological role of TMEM229A in cancer remains unknown. The present study aimed to investigate the expression level of TMEM229A in non‑small cell lung cancer (NSCLC), as well as its effect and mechanism on NSCLC progression. Clinical specimens from patients with NSCLC were enrolled from the First People's Hospital of Huzhou (Huzhou, China). TMEM229A expression was detected using reverse transcription‑quantitative PCR (RT‑qPCR), western blotting and immunohistochemical analysis. The relationship between TMEM229A expression and the survival rate of patients with NSCLC was analyzed using Kaplan‑Meier Plotter datasets. The effects of TMEM229A on cell proliferation, migration and invasion were detected using Cell Counting Kit‑8, colony formation, soft agar, real‑time cellular analysis and Transwell assays. The expression levels of epithelial‑mesenchymal transition (EMT)‑related proteins, as well as ERK and AKT phosphorylation were determined via RT‑qPCR and western blot analysis. The results demonstrated that TMEM229A expression was significantly downregulated in human NSCLC tissues and in several cell lines compared with adjacent normal lung tissues and BEAS‑2B cells, respectively. Survival analysis of lung adenocarcinoma and squamous cell lung carcinoma cases identified that low TMEM229A expression was associated with a poor prognosis. The in vitro assays indicated that overexpressing TMEM229A significantly inhibited cell proliferation, migration and invasion, while TMEM229A knockdown had the opposite effect. Mechanistically, TMEM229A overexpression effectively increased E‑cadherin expression and reduced N‑cadherin, snail family transcriptional repressor 1 and MMP2 expression, indicating that EMT was suppressed. In addition, overexpression of TMEM229A reduced the expression levels of phosphorylated (p)‑ERK and p‑AKT, and this effect was partially suppressed by the incorporation of specific ERK inhibitor PD98059. Collectively, the results of the present study demonstrated that the effects of TMEM229A on inhibiting cell proliferation, migration and invasion were partially mediated by inactivating the ERK signaling pathway, thereby providing a potential therapeutic target for the treatment of NSCLC.

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Dataset Information

CCL21/CCR7 prevents apoptosis via the ERK pathway in human non-small cell lung cancer cells.

Publications

CCL21/CCR7 prevents apoptosis via the ERK pathway in human non-small cell lung cancer cells.

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