Effect of purified fractions from cell culture supernate of high‐density pre‐B acute lymphoblastic leukemia cells (ALL3) on the growth of ALL3 cells at low density

Abstract

The mechanisms underlying the aberrant growth and interactions between cells are not understood very well. The pre-B acute lymphoblastic leukemia cells directly obtained from an adult patient grow very poorly or don't grow at all at low density (LD), but grow better at high starting cell density (HD). We found that the LD ALL3 cells can be stimulated to grow in the presence of diffusible, soluble factors secreted by ALL3 cells themselves growing at high starting cell density. We then developed a biochemical purification procedure that allowed us to purify the factor(s) with stimulatory activity and analyzed them by nanoliquid chromatography-tandem mass spectrometry (nanoLC-MS/MS). Using nanoLC-MS/MS we have identified several proteins which were further processed using various bioinformatics tools. This resulted in 8 protein candidates which might be responsible for the growth activity on non-growing LD ALL3 cells and their involvement in the stimulatory activity are discussed.

AFM study shows prominent physical changes in elasticity and pericellular layer in human acute leukemic cells due to inadequate cell–cell communication

“…A newly established cell line freshly obtained from the leukemic cells growing as ascitic cells in the pleural effusion of a terminally ill patient with Ph+ acute lymphoblastic leukemia (ALL3) is used in this work. ALL3 is a clonal proliferation of p190 BCR-ABL transformed pre B cells that arise in the bone marrow [30,34]. We observed that there is a significant difference in the growth rate of ALL3 cells at low (LD) and high starting cell densities (HD).…”

“…However, the influence of cell-cell communication on biomechanical properties of cells has not been systematically studied. At the same time, it is known that the collective behavior is an important feature and it is involved in regulating many biological processes such as cell migration, stem cell maintenance, growth of proper organ size, immune system regulation, hematopoiesis, homeostasis and regeneration [27][28][29][30][31][32][33][34]. Individual cells utilize 'autocrine' and/or 'paracrine' factors to coordinate these beneficial collective behaviors.…”

“…Individual cells utilize 'autocrine' and/or 'paracrine' factors to coordinate these beneficial collective behaviors. Even prokaryotic cells utilize these quorum-sensing (QS) molecules to 'count' their population numbers to determine whether the conditions are suitable to perform specific tasks including complex behaviors, such as formation of complex biofilms, antibiotic production, motility, sporulation, virulence, competence, conjugation and symbiosis [30,[34][35][36][37][38]. Cancer cell populations also function collectively to initiate and maintain abnormal cell proliferation, permit invasion and metastasis, avoid inhibition by the immune system, develop therapeutic resistance, and metabolic reprogramming [39,40].…”

“…Cancer cell populations also function collectively to initiate and maintain abnormal cell proliferation, permit invasion and metastasis, avoid inhibition by the immune system, develop therapeutic resistance, and metabolic reprogramming [39,40]. The underlying biochemical and biological QS mechanisms responsible for the deviant behavior of cancer cell populations are still poorly understood [30,34,[41][42][43].…”

“…Thus, cell proximity as well as overall cell density are important. Labeling studies with proliferation markers Ki67, BrdU or EdU showed that the LD ALL3 cells were poised to begin proliferating but could not do so without being triggered by supernate (HDSN) from ALL3 cells or some other normal or leukemic cells growing at HD [30,34].…”