Department of Biotechnology
inStem (Institute for Stem Cell Science and Regenerative Medicine)

Stromal cells downregulate miR-23a-5p to activate protective autophagy in acute myeloid leukemia.

Publication Type

Journal Article

Date of Publication

September 30, 2019

Journal

Cell death & disease

Volume/Issue

10/10

ISSN

2041-4889

Complex molecular cross talk between stromal cells and the leukemic cells in bone marrow is known to contribute significantly towards drug-resistance. Here, we have identified the molecular events that lead to stromal cells mediated therapy-resistance in acute myeloid leukemia (AML). Our work demonstrates that stromal cells downregulate miR-23a-5p levels in leukemic cells to protect them from the chemotherapy induced apoptosis. Downregulation of miR-23a-5p in leukemic cells leads to upregulation of protective autophagy by targeting TLR2 expression. Further, autophagy inhibitors when used as adjuvants along with conventional drugs can improve drug sensitivity in vitro as well in vivo in a mouse model of leukemia. Our work also demonstrates that this mechanism of bone marrow stromal cell mediated regulation of miR-23a-5p levels and subsequent molecular events are relevant predominantly in myeloid leukemia. Our results illustrate the critical and dynamic role of the bone marrow microenvironment in modulating miRNA expression in leukemic cells which could contribute significantly to drug resistance and subsequent relapse, possibly through persistence of minimal residual disease in this environment.

Alternate Journal

Cell Death Dis

PubMed ID

31570693

PubMed Central ID

PMC6769009

Authors

Saravanan Ganesan
Hamenth Kumar Palani
Vairavan Lakshmanan
Nithya Balasundaram
Ansu Abu Alex
Sachin David
Arvind Venkatraman
Anu Korula
Biju George
Poonkuzhali Balasubramanian
Dasaradhi Palakodeti
Neha Vyas
Vikram Mathews

Keywords

Tumor Microenvironment
Apoptosis
Xenograft Model Antitumor Assays
Gene Expression Regulation, Neoplastic
Autophagy
Daunorubicin
Leukemia, Myeloid, Acute
Neoplasm, Residual
Stromal Cells
Animals
Toll-Like Receptor 2
Mice
Female
Male
Humans
Bone Marrow Cells
MicroRNAs