Glioblastoma is the most common malignant brain tumor in adults and it is currently treated with a combination of surgery, radiotherapy and chemotherapy with temozolomide (TMZ). Many patients show resistance to TMZ, which is a challenge in the treatment of this type of brain cancer. New strategies are being tested, like the inhibition of EZH2, a histone methyltransferase which is overexpressed in cancer cells, leading to angiogenesis and metastasis. In this work, the EZH2 inhibitor DZNeP was tested in A172 glioblastoma cells and in A172-TMZ-resistant glioblastoma cells. Inhibition of cell proliferation, adhesion, colony formation, and migration was noted in control and TMZresistant glioblastoma cells after DZNeP treatment. At the level of EZH2 target gene expression, DZNeP decreased EZH2 expression, and increased the expression of its target genes (E-cadherin and TIMP3), which might probably contribute to inhibiting the development of a cancer metastatic phenotype. Finally, DZNeP negatively regulated the TGFß pathway. In conclusion, we propose that inhibition of EZH2 might be considered as a therapeutic strategy against glioblastoma.