Role of ITGA5 in Autophagy, Migration and Invasion of Acute Myeloid Leukemia Cells

Abstract Introduction: Acute myeloid leukemia is a heterogeneous hematological malignancy characterized by massive proliferation of abnormally differentiated myeloid blasts or promyelocytes. Genetic factors, environmental factors, abnormal bone marrow microenvironment and gene mutations are closely related to the occurrence and development of AML. Integrin family is gradually well known because of its important role in cell adhesion and migration. It is found that integrins, as an important kind of extracellular matrix receptor, participate in the regulation of cell adhesion, migration, proliferation and other physiological processes, and are closely related to the occurrence and development of tumors. Through proteomic sequencing analysis, we found that the expression of integrins ITGA5, ITGA V, and ITGA L in AML leukemia cells was significantly increased. In previous experiments, we verified that ITGA5 is also highly expressed in Molm-13, MV-4-11, and Kasumi-1 cells by QPCR and Western blot, which can effectively promote the chemotherapy of cytarabine. Subsequently, we made related studies on the role of ITGA5 in autophagy, migration and invasion of acute myeloid leukemia cells.

Methods: First, we used ITGA5 lentivirus to transfect Molm-13 and MV-4-11 cells, and after successful transfection, we used cytarabine and doxorubicin to verify the chemosensitization effect after knockdown of ITGA5. We collected ITGA5 knockdown Molm-13 cells for transcriptomic sequencing. Then, Western blot was used to detect the expression of apoptosis-related proteins, autophagy-related proteins and pathway proteins in AML cells. We observed the ultrastructural changes of AML cells after knockdown of ITGA5 by transmission electron microscopy. We verified the effect of ITGA5 on the migration and invasion ability of AML cells through migration and invasion experiments.

Results: Compared with the previous experimental inhibition, inhibition of ITGA5 can increase the killing effect of chemotherapeutic drugs on AML cells. Subsequently, we collected ITGA5 knockdown Molm-13 cells for transcriptome sequencing, and found that knockdown of ITGA5 can increase the expression of apoptotic protein-related genes, but also reduce the expression of autophagy-related genes. Subsequently, we verified by Western blot that after knocking down ITGA5, the expression of apoptosis-related proteins Cleaved Caspase-3, Cleaved Caspase-9, and Cleaved PARP was more expressed in AML cells treated with chemotherapeutic drugs, and the expression of SQSTM1/p62 and mTOR increased after knocking down ITGA5. The expression of autophagy marker MAP1LC3 was reduced, thus inhibiting autophagy. In addition, we found that inhibition of ITGA5 can significantly inhibit the migration and invasion of AML cells.

Conclusion:ITGA5 is highly expressed in AML. Knockdown ITGA5 can play a better role in chemosensitization, that is, enhance the killing effect of cytarabine and doxorubicin on AML cells, and also inhibit the migration and invasion of AML cells. After inhibiting ITGA5, it negatively regulates the phosphorylation of PI3K/AKT, promotes the activation of Caspase 3, Caspase 9, and PARP proteins, and promotes the production of AML cell apoptosis, thus exerting chemosensitization and inhibiting autophagy. ITGA5 is expected to be a target of AML clinical treatment.

Disclosures No relevant conflicts of interest to declare.

No relevant conflicts of interest to declare.