In situ detection of protein-protein interaction by proximity ligation assay in patient derived brain tumor stem cells.

Improper or aberrant protein-protein interactions can lead to severe human diseases including cancer. Here, we describe an adapted proximity ligation assay (PLA) protocol for the assessment of galectin-1-HOXA5 interaction in brain tumor stem cells (BTSCs). We detail the steps for culturing and preparation of BTSCs followed by PLA and detection of protein interactions in situ using fluorescent microscopy. This PLA protocol is optimized specifically for BTSCs and includes key controls for effective result analysis. For complete details on the use and execution of this protocol, please refer to Sharanek et al. (2021).