Currently available CAR T cell therapy is unable to promote tumor regression in patients with solid tumors in part due to presence of dense extracellular matrix (ECM). In order to eliminate tumors, adoptively transferred T cells must home to the tumors before they can execute their effector functions. The extracellular matrix (ECM) and the stroma surrounding the tumor presents a significant physical barrier and successfully prevent T-cell access to tumor cells. We genetically modified CAR T cells to overexpress ECM degrading enzyme, matrix metallopeptidase 8 (MMP8) and observed in our in vitro and animal studies that MMP8 overexpressing CAR T cells showed improved tumor cell killing efficacy compared to CAR T cell alone. We demonstrate that MMP8 can be used to overcome the hurdles of current CAR T cell therapy especially in patients with stroma-rich solid tumors by overcoming the physical barriers posed by ECM. More broadly, expression of MMP8 can be used to improve the tumor infiltrating capabilities of any cell-based immunotherapy against solid tumors including T cells, tumor infiltrating lymphocytes (TILs), CAR macrophages, and NK cells (with and without CAR).