Mesenchymal stem cells (MSCs) are a heterogeneous population that can be isolated from various tissues. Their ability to self-renew and modulate the immune system has generated increasing interest in using these cells for therapeutic applications. Additionally, MSCs have a natural tendency to migrate towards inflammatory sites such as tumors, making them ideal candidates for drug delivery. Loading MSCs with drug molecules requires sophisticated techniques that need to be both efficient and gentle. To achieve this, we will employ photoporation, an emerging delivery technique that uses a pulsed laser and photothermal nanosensitizers to temporarily permeabilize the plasma membrane. We will investigate both photothermal nanoparticles and nanosubstrates for loading drugs and genetically modifying MSCs. On one hand, we will explore the use of modified MSCs for treating glioblastoma, one of the most aggressive forms of brain cancer. Using MSCs is highly advantageous due to their functionality and their ability to efficiently cross the blood-brain barrier, which is a significant hurdle for traditional therapeutics. On the other hand, we will investigate modified MSCs for treating osteoarthritis, one of the most common degenerative bone diseases where current treatment focuses on symptom relief. The efficacy of modified MSCs will be tested through co-cultures with relevant cell types and animal models for glioblastoma and osteoarthritis.