Original ArticlesVCAM-1 secreted from cancer-associated fibroblasts enhances the growth and invasion of lung cancer cells through AKT and MAPK signaling
Introduction
Lung cancer is the leading cause of cancer death and exhibits the highest morbidity and mortality globally, the overall 5-year survival rate is 15% [1,2]. Most lung cancer patients die of metastasis, thus, understanding the mechanism of lung cancer metastasis is urgently needed [3]. Recent studies have shown that cancer progression and metastasis are not only associated with the properties of tumor cells, but also depend on the tumor microenvironment (TME) [4]. Among the stromal cells of TME, cancer-associated fibroblasts (CAFs) are a dominant component, exhibiting a classic spindle-shape morphology with a potential for planar polarity and over-expression of marker proteins including alpha-smooth muscle actin (α-SMA) and fibroblast-activated protein (FAP) [5,6]. Accumulating research has demonstrated that cancer cells can establish cross-talk with CAFs to enhance tumor metastasis [7], and a strong association between CAFs and poor prognosis has been shown in several types of cancer, including lung cancer [[8], [9], [10]].
CAFs can secrete cytokines, growth factors, CAF-specific proteins and exosomes to support cancer cell growth, metastasis and confer chemoresistance to lung cancer [11,12]. CAFs support the growth of lung cancer cells in vivo by the secretion of the cytokines cardiotrophin-like cytokine factor 1 (CLCF1) and IL6 that directly stimulate the growth of cancer cells [13], IL-22 secreted from CAFs significantly increases the proliferation, migration and invasion of lung cancer cells but reduces apoptosis via the activation of PI3K-Akt-mTOR signaling [14]. A subset of CAFs, CD90 (+) CAFs, secrete insulin-like growth factor-II (IGF-II) activated IGF1R signaling in cancer cells, induce nanog expression and promote stemness [15]. Also, IGF-1 and hepatocyte growth factor(HGF), secreted by CAFs, synergistically induce Annexin A2(ANXA2) expression, thus promoting epithelial–mesenchymal transition (EMT) and drug resistance in non-small cell lung cancers (NSCLCs) [16]. Recent research has found that CAFs deliver SNAIL1 to recipient cells via exosomes and induce EMT in lung cancer cells [17].
To better understand the mechanism of the interaction of CAFs with lung cancer cell in growth and invasion, the current study demonstrated that CAF-conditional medium (CM) enhanced the proliferation and invasion of the recipient cancer cells. Interestingly, we found that vascular cell adhesion molecule-1 (VCAM-1), secreted from CAFs, was upregulated compared with the normal fibroblasts (NFs), and blocking the expression of VCAM-1 in CAFs led to the attenuation of the proliferation and invasion of cancer cells. Moreover, we verified that VCAM-1 secreted from CAFs activated the AKT and MAPK pathway via a receptor, the α4β1 integrin (also known as very-late antigen, VLA-4) in cancer cells. In vivo, we proved that VCAM-1 increased tumor growth. Collectively, the present work provides solid evidence that VCAM-1, secreted from CAFs, enhances the growth and invasion of lung cancer cells, implying that VCAM-1 may be a potential anti-metastasis therapeutic target of lung cancer.
Section snippets
Cell culture and reagents
A549 and H358 cells were obtained from the American Type Culture Collection (ATCC, Manassas, VA, USA). A549 was cultured in DMEM/F12 (Gibco BRL, Gaithersburg, MD, USA) supplemented with 10% fetal bovine serum (FBS, Hyclone, Logan, UT, USA), and H358 cells were cultured in RPMI 1640 (Gibco BRL) supplemented with 10% FBS at 37 °C in a 5% CO2 incubator. Recombinant human VCAM-1(150-04-100) was obtained from Peprotech (Rocky Hill, NJ, USA). VCAM-1(AF809) and Sheep IgG (5-001-A) were purchased from
The conditional medium (CM) of CAFs promotes the proliferation, migration and invasion of recipient lung cancer cells
Primary cells were isolated from lung cancer and adjacent normal tissues of three patients. Consistently with previous reports [3], the morphology of the two primary cells is a long-spindle shape, suggesting that these cells were fibroblasts (Fig. 1A). Western blotting analysis results indicated that more α-SMA and FAP were expressed in CAFs than NFs in three paired primary cultured cells (Fig. 1B). Meanwhile, α-SMA, FAP and PDFGR-α of CAFs were higher than two generation NFs (NFs-P2), and the
Discussion
Numerous evidence has demonstrated that CAFs play a critical role in cancer procession, including altering the immune response and inflammation, maintaining stemness and metabolism, inhibiting apoptosis, and enhancing proliferation, invasion and metastasis, and so on [29,30]. Although some studies have found that CAFs are involved in the growth and metastasis of lung cancer [3,14,31], the role of CAFs in lung cancer and its mechanism have still not been fully elucidated. Here, we further
Declaration of competing interest
The authors declare no conflict of interest.
Acknowledgements
This work was supported by the National Natural Science Foundation of China (Grant Nos. 81672761 and 81372182) and the Natural Science Foundation of Hunan Province (2018JJ2545).
References (41)
- et al.
Primary non-small cell lung cancer response upon treatment with denosumab
Lung Cancer
(2013) - et al.
Phenotypic and functional heterogeneity of cancer-associated fibroblast within the tumor microenvironment
Adv. Drug Deliv. Rev.
(2016) - et al.
Prognostic relevance of cancer-associated fibroblasts in human cancer
Semin. Cancer Biol.
(2014) - et al.
The role of tumor stroma in cancer progression and prognosis: emphasis on carcinoma-associated fibroblasts and non-small cell lung cancer
J. Thorac. Oncol.
(2011) - et al.
Cancer-associated fibroblasts promote epithelial-mesenchymal transition and EGFR-TKI resistance of non-small cell lung cancers via HGF/IGF-1/ANXA2 signaling
Biochim. Biophys. Acta (BBA) - Mol. Basis Dis.
(2018) - et al.
Cancer-associated fibroblasts promote hepatocellular carcinoma metastasis through chemokine-activated hedgehog and TGF-beta pathways
Cancer Lett.
(2016) - et al.
VCAM-1 promotes osteolytic expansion of indolent bone micrometastasis of breast cancer by engaging alpha4beta1-positive osteoclast progenitors
Cancer Cell
(2011) - et al.
Macrophage binding to receptor VCAM-1 transmits survival signals in breast cancer cells that invade the lungs
Cancer Cell
(2011) - et al.
Osteoblast-secreted WISP-1 promotes adherence of prostate cancer cells to bone via the VCAM-1/integrin alpha4beta1 system
Cancer Lett.
(2018) - et al.
Membrane microvesicles as mediators for melanoma-fibroblasts communication: roles of the VCAM-1/VLA-4 axis and the ERK1/2 signal pathway
Cancer Lett.
(2015)
Paracrine and epigenetic control of CAF-induced metastasis: the role of HOTAIR stimulated by TGF-ss1 secretion
Mol. Cancer
IL-6 secreted from cancer-associated fibroblasts mediates chemoresistance in NSCLC by increasing epithelial-mesenchymal transition signaling
J. Thorac. Oncol.
Epstein-Barr virus noncoding RNAs from the extracellular vesicles of nasopharyngeal carcinoma (NPC) cells promote angiogenesis via TLR3/RIG-I-mediated VCAM-1 expression
Biochim. Biophys. Acta (BBA) - Mol. Basis Dis.
Reciprocal leukemia-stroma VCAM-1/VLA-4-dependent activation of NF-kappaB mediates chemoresistance
Blood
Cancer statistics
CA A Cancer J. Clin.
Cancer-associated fibroblasts enhance metastatic potential of lung cancer cells through IL-6/STAT3 signaling pathway
Oncotarget
Microenvironmental regulation of tumor progression and metastasis
Nat. Med.
The biology and function of fibroblasts in cancer
Nat. Rev. Cancer
The roles of tumor- and metastasis-promoting carcinoma-associated fibroblasts in human carcinomas
Cell Tissue Res.
mir-1-mediated paracrine effect of cancer-associated fibroblasts on lung cancer cell proliferation and chemoresistance
Oncol. Rep.
Cited by (72)
Enigmatic exosomal connection in lung cancer drug resistance
2024, Molecular Therapy Nucleic Acids“Reinforcement” by Tumor Microenvironment: The Seventh “R” of Radiobiology
2024, International Journal of Radiation Oncology Biology PhysicsCancer-associated fibroblasts: Versatile mediators in remodeling the tumor microenvironment
2023, Cellular SignallingCitation Excerpt :In addition, apCAFs express MHC II and CD74, which contribute to antigen presentation and immune modulation functions [13,35]. CAFs are highly heterogeneous stromal cells, and their effects on tumor cells are mediated by a complex and complicated signaling pathways that involve transforming growth factor-beta (TGF-β) [36,37], MAPK [38,39], PI3K/AKT/mTOR [40,41], JAK/STAT [42,43], Wnt/β-catenin [44], NF-κB [45], and integrin β1-FAK-Src [46,47]. All of these signaling networks of CAF influence tumor cells and have enormous potential as targets for impeding CAF-mediated tumor promotion.
- 1
These authors contributed equally to this work.