(j) CTR and RAB2A MCF10A cells were transfected with Str-KDEL_SBP-EGFP-E-cadherin (green). At the indicated time points after the addition of biotin, cells were fixed, and stained without permeabilization with anti-GFP antibody, followed by Alexa568-conjugated secondary antibody (red). The cell surface and total levels of SBP-EGFP-E-cadherin at 60 min after the addition of biotin were quantified using ImageJ software on non-saturated images, and surface/total ratio was expressed as a surface GFP index (relative to control cells). Bar, 20 µm. ***, P < 0.001. 