Mesenchymal stem cells in acute myeloid leukemia: a focus on mechanisms involved and therapeutic concepts

Drug resistance in cancer, especially in leukemia, creates a dilemma in treatment planning. Consequently, studies related to the mechanisms underlying drug resistance, the molecular pathways involved in this phenomenon, and alternate therapies have attracted the attention of researchers. Among a variety of therapeutic modalities, mesenchymal stem cells (MSCs) are of special interest due to their potential clinical use. Therapies involving MSCs are showing increasing promise in cancer treatment and anticancer drug screening applications; however, results have been inconclusive, possibly due to the heterogeneity of MSC populations. Most recently, the effect of MSCs on different types of cancer, such as hematologic malignancies, their mechanisms, sources of MSCs, and its advantages and disadvantages have been discussed. There are many proposed mechanisms describing the effects of MSCs in hematologic malignancies; however, the most commonly-accepted mechanism is that MSCs induce tumor cell cycle arrest. This review explains the anti-tumorigenic effects of MSCs through the suppression of tumor cell proliferation in hematological malignancies, especially in acute myeloid leukemia.