Investigating Effects of Acidic pH on Proliferation, Invasion and Drug-Induced Apoptosis in Lymphoblastic Leukemia.

Some studies have shown that extracellular pH in tumors, which results in tumor progression, is less than that in normal tissues. The aim of this study was to investigate the effects of extracellular acidic pH on proliferation, invasion, and drug-induced apoptosis in acute lymphoblastic cells. The cells were cultured in different pH (pH 6.6 and pH 7.4) for 12 days. Cell proliferation was assessed by MTT assay and cell invasion was assayed by invasion assay and gene expression analysis of MMP-9. Drug-induced apoptosis was evaluated after exposure to doxorubicin for 24 hours by annexin V/PI staining and gene expression analysis of BAX pro-apoptotic protein. The results indicated the enhanced growth and invasion of leukemic cells at pH 6.6 (P ≤ 0.05). Furthermore, the cells at pH 6.6 were resistant to apoptosis by doxorubicin (P ≤ 0.05). It can be concluded that acidic pH increases the proliferation, invasion and reduces the drug-induced apoptosis in acute lymphoblastic leukemia. Extracellular acidity can influence the behavior of leukemic cells and therefore, the manipulation of extracellular liquid can be selected as a therapeutic strategy for leukemia, especially for acute lymphoblastic leukemia.

Differential characteristics of CD133(+) and CD133 (-) Jurkat cells.

T cell acute lymphoblastic leukemia (T-ALL) is a hematological disease including malignancy of T cell precursors. There are some T-ALL patients that are drug-resistant. A major cause of treatment failure in cancers can be associated with the existence of cancer stem cells. The identification of these cell populations helps us to clarify resistance mechanisms and rely on special markers for recognizing cancer stem cells. CD133 is one of the markers that is used for the identification of cancer stem cells. In this study, we evaluated CD133(+) and CD133(-) characteristic cells in Jurkat cells by assay proliferation, invasion, and apoptosis. CD133(+) and CD133(-) Jurkat cells were separated and immediately analyzed for proliferation, invasion, and doxorubicin-induced apoptosis. Proliferation, invasion, and resistance to chemotherapy of CD133(+) Jurkat cells were significantly more than CD133(-) Jurkat cells. Also, our results showed that CD133(+) Jurkat cells expressed ABCG2 gene more than CD133(-) Jurkat cells. In conclusion, CD133 marker could be introduced as a specific marker of cancer stem cells in Jurkat cell line.