SSTR2 Expression and Ga-DOTATOC Uptake

A549 and Panc-1 cell lines with different expression levels of GFP (low to high) were seeded in 6-well plates at 5×10⁵ cells per well in triplicate and allowed to grow for 48 h. To quantitate the SSTR2 expression, Western blot assay was performed on the samples as previously described 21 (link). Briefly, whole protein extract purification was performed on the cell sediments. Protein samples (30 µL) were loaded onto SDS-polyacrylamide gels (Bio-Rad) and run at 120 V and 14 mA for 1.5 h. Gels were blotted on polyvinylidene difluoride (PVDF) membrane and the blots incubated overnight at 4 °C with anti-human SSTR2 monoclonal antibody (Abcam) at 1/500 dilution. ß-actin monoclonal antibody (Santa Cruz) at 1/1000 dilution was used as an internal control. Detection was performed using the BM Chemiluminescence Western Blotting Kit (Roche) and imaged on the in vivo Multispectral FX imaging system (Carestream). The SSTR2 expression corrected for ß-actin was correlated to the ⁶⁸Ga-DOTATOC uptake per cell.