Date on Master's Thesis/Doctoral Dissertation


Document Type

Master's Thesis

Degree Name



Biochemistry and Molecular Biology

Committee Chair

Hu, Chuan

Author's Keywords

VAMP3; Cell migration; Melanoma; Integrin trafficking


Integrins; Melanoma; Cells--Motility


Integrins are major receptors for cell adhesion to the extracellular matrix, and play key roles in various cellular processes including adhesion, migration, proliferation and survival. Apart from developmental and physiological events, integrins are involved in many pathological conditions including cancer metastasis. During cell migration, the exocytosis of integrins at the cell front contributes to the formation and stabilization of protrusions. Previous studies showed that VAMP3, a SNARE protein that mediates exocytosis, is important in integrin trafficking and cell migration. However, the mechanism by which VAMP3 participates in integrin trafficking is not clear. Since VAMP3 is over expressed in melanoma, the current study determines the roles of VAMP3 in melanoma cell migration and integrin trafficking. shRNA-induced silencing of VAMP3 inhibited the migration of B16F10 melanoma cells by more than 60% without affecting cell proliferation. VAMP3 knockdown diminished cell adhesion to Matrigel and fibronectin. Furthermore, VAMP3 silencing resulted in the accumulation of ß1, a3 and a5 integrins in lysosomes, indicating that VAMP3 mediates vesicle trafficking of a3 ß1 and a5 ß1 integrins. For the first time, this study examined the effect of VAMP3 knockdown on metastasis of melanoma in vivo using an experimental metastasis assay in nude mice. It seemed that melanoma cells can metastasize to the lung even when VAMP3 is depleted and we suggest more quantitative experiments to determine the effect of VAMP3 knockdown in melanoma pulmonary metastasis in vivo.