Migration-promoting role of VEGF-C and VEGF-C binding receptors in human breast cancer cells

Abstract

Vascular endothelial growth factor C (VEGF-C) is a lymphangiogenic factor over-expressed in highly metastatic, cyclooxygenase (COX)-2 expressing breast cancer cells. We tested the hypothesis that tumour-derived VEGF-C may play an autocrine role in metastasis by promoting cellular motility through one or more VEGF-C-binding receptors VEGFR-2, VEGFR-3, neuropilin (NRP)-1, NRP-2, and integrin α 9 β 1. We investigated the expression of these receptors in several breast cancer cell lines (MDA-MB-231, Hs578T, SK-BR-3, T-47D, and MCF7) and their possible requirement in migration of two VEGF-C-secreting, highly metastatic lines MDA-MB-231 and Hs578T. While cell lines varied significantly in their expression of above VEGF-C receptors, migratory activity of MDA-MB-231 and Hs578T cells was linked to one or more of these receptors. Depletion of endogenous VEGF-C by treatments with a neutralising antibody, VEGF-C siRNA or inhibitors of Src, EGFR/Her2/neu and p38 MAP kinases which inhibited VEGF-C production, inhibited cellular migration, indicating the requirement of VEGF-C for migratory function. Migration was differentially attenuated by blocking or downregulation of different VEGF-C receptors, for example treatment with a VEGFR-2 tyrosine kinase inhibitor, NRP-1 and NRP-2 siRNA or α 9 β 1 integrin antibody, indicating the participation of one or more of the receptors in cell motility. This novel role of tumour-derived VEGF-C indicates that breast cancer metastasis can be promoted by coordinated stimulation of lymphangiogenesis and enhanced migratory activity of breast cancer cells.

Downregulation of VEGF-C expression in lung and colon cancer cells decelerates tumor growth and inhibits metastasis via multiple mechanisms

“…Several of these effects were described earlier and confirmed in our study. In fact, similar to other investigators (Su et al, 2006;Timoshenko et al, 2007;Kodama et al, 2008;Chen et al, 2010), we observed that in vitro cancer cells with downregulated VEGF-C show reduced proliferation and/or migration. Using in vivo analysis, which allows to reveal not only autocrine but also paracrine effects, we found that in addition to deceleration of tumor growth, VEGF-C downregulation caused inhibition of lymphangiogenesis in tumor and surrounding tissues.…”

“…It binds to Flt4/VEGF receptor 3 (VEGFR3), a receptor tyrosine kinase that is expressed in lymphatic endothelial cells (Joukov et al, 1996), certain non-endothelial cells such as osteoblasts (Orlandini et al, 2006) and many cancer cell types (Strizzi et al, 2001;Jackson et al, 2002;Su et al, 2006;Timoshenko et al, 2007). With significantly lower affinity VEGF-C interacts with VEGFR2, which is primarily involved in the induction of hemangiogenesis (Skobe et al, 1999;Shibuya and Claesson-Welsh, 2006) and coreceptors, including the neuropilin-2 expressed on veins and lymphatic vessels (Karkkainen et al, 2001;Karpanen et al, 2006;Xu et al, 2010).…”

“…Initially, it was thought that VEGF-C synthesized in cancer cells promotes metastasis mainly through induction of lymphangionenesis in tumor tissues and sentinel lymph nodes that facilitated the spread of cancer cells via the lymphatic vessels (Mandriota et al, 2001;He et al, 2002;Hoshida et al, 2006). However, several recent studies reported that autocrine regulation of cancer cells migration via VEGF-C/VEGFRs is an important inducer of tumor cell proliferation, invasion and metastasis (Timoshenko et al, 2007;Kodama et al, 2008;Su et al, 2006Su et al, , 2008Chen et al, 2010). This stimulation of cancer cell motility is partly mediated by activation of VEGFR3-Src-p38MAPK-C/EBP-contactin-1 pathway (Su et al, 2006); however, other possible mechanisms of induction of cell locomotion by VEGF-C remain largely unknown.…”

Targeting COX-2 and EP4 to control tumor growth, angiogenesis, lymphangiogenesis and metastasis to the lungs and lymph nodes in a breast cancer model

“…In addition to its role in promoting lymphangiogenesis, we found that VEGF-C production by breast cancer cells served as an autocrine stimulus for their motility by binding to a diverse group of VEGF-C receptors. 23 Although VEGF-C production and lymphangiogenesis was a direct consequence of COX-2 expression in human breast cancer, 17 we found that HER-2, often co-expressed with COX-2 in human breast cancer, had no direct role in VEGF-C upregulation or lymphangiogenesis, and that its role, if any, was COX-2 dependent. 21 The facts that COX-2 is overexpressed in about half of breast cancer specimens 7 inclusive of DCIS 24 and invasive carcinomas, 21 and has multiple roles in breast cancer progression and metastasis, make this molecule a reasonable therapeutic target.…”

Role of vascular endothelial growth factor receptor-3/Flt-4 in early-stage cervical cancer

“…Therefore, it is speculated that VEGFRs may be involved in the phenotypic transformation of carcinoma cells to promote lymphangiogenesis in cervical cancer. The results obtained by in vitro migration and cervical mucus invasion tests (11,12) indicated that strong invasive cancer cell lines, such as SiHa and breast cancer cell lines MDA-MB-231 and Hs578T, express Flt-4 (i.e., VEGFR-3) and VEGF-C. Recombinant human VEGF-C (Cys156Ser) facilitates the migration and invasion of cancer cells. However, cellular migration and invasion were greatly reduced when recombinant Flt-4/Fc was used to block the VEGF-C receptor (VEGFR-3/Flt-4).…”