The differences in thermal profiles between normal and leukemic cells exposed to anticancer drug evaluated by differential scanning calorimetry

Abstract

Chronic lymphocytic leukemia (CLL) is a heterogenous disease with an imbalance between apoptosis and cell proliferation. Therefore, the main goal in CLL therapy is to induce apoptosis and effectively support this process in transformed B lymphocytes. In the current study, we have compared differential scanning calorimetry (DSC) profiles of nuclei isolated from CLL cells and normal mononuclear cells exposed to cladribine or fludarabine combined with mafosfamide (CM; FM), and additionally to CM combined with monoclonal antibody-rituximab (RCM) for 48 h, as well as in culture medium only (controls). Under current study, the mononuclear cells from peripheral blood (PBMCs) of healthy individuals have been included. The obtained results have shown the presence of thermal transition at 95 ± 5°C in most of nuclear preparations (92.2 %) isolated from blood of CLL patients. This thermal characteristic parameter was changed after drug exposure, however, to a different extent. These thermal changes were accompanied by the decrease of cell viability, an elevation of apoptosis rate and the changes in expression/proteolysis of poly(ADP-ribose)polymerase-1-main marker of apoptosis. Importantly, in DSC profiles of nuclear preparations of PBMCs from blood of healthy donors exposed to investigated drug combinations and control CLL cells, the lack of such changes was observed. Our results confirmed that DSC technique complemented with other biological approaches could be helpful in tailoring therapy for CLL patients. Keywords Chronic lymphocytic leukemia Á Differential scanning calorimetry Á Anti-leukemic tailored therapy Á Purine analogs Á Mafosfamide Á Rituximab Paweł Góralski and Małgorzata Rogalińska should be considered jointly as the first authors.

Relationship between in vitro drug sensitivity and clinical response of patients to treatment in chronic lymphocytic leukemia

“…Moreover, the obtained results also revealed that the decrease (or even loss) of thermal transition at 95±5˚C in thermal scans of nuclear preparations of cll cells, after both in vivo and in vitro drug administration, are attributable to chromatin fragmentation during apoptosis (23,24).…”

“…it has been reported by our laboratory that an additional thermal transition occurs at 95±5˚C in the DsC profiles of nuclear fraction preparations obtained from the mononuclear cells of patients in an advanced stage of cll, along with the main transition at 83±3˚C characteristic for healthy donors (22,23). Moreover, the obtained results also revealed that the decrease (or even loss) of thermal transition at 95±5˚C in thermal scans of nuclear preparations of cll cells, after both in vivo and in vitro drug administration, are attributable to chromatin fragmentation during apoptosis (23,24).…”

“…in summary, the results of our studies revealed that determination of the in vitro cll cell sensitivity based on purine analogs and their combinations with alkylating agent would be instrumental in the development of personalized therapy. it should be stated that from our point of view in vitro study gives the opportunity for cll status analysis, before and during drug application (18,(22)(23)(24). it reflects a special importance for a subset of patients resistant to therapy, as well as for those heavily pre-treated or those in weak condition.…”

Personalized therapy tests for the monitoring of chronic lymphocytic leukemia development

“…Considerable differences in leukemic cell reactivity were observed in cell samples incubated with Rit, with the cells appearing resistant to Rit in the stable form of the disease. Previous studies have reported that in progressive CLL, additional thermal transition occurs at ~95±5°C (15,19,20,26,28,29), which decreases in the case of the apoptotic activity. The presence of a thermal transition at 95°C following CLL incubation with ≥1 of the agents indicates that the leukemic cells in the stable form of the disease are resistant to Rit.…”

Influence of oxidative injury and monitoring of blood plasma by DSC on breast cancer patients

“…Later, differential scanning calorimetry (DSC) studies examined a number of different cancers (melanoma malignum, myeloma, colorectal cancer, cervical cancer, leukemia, etc.) and other diseases (e.g., psoriasis, schizophrenia, chronic obstructive pulmonary disease) revealed significant changes in the plasma thermogram when compared with healthy controls [16][17][18][19][20]. Moreover, examination of DSC data in different clinical stages of cancer patients should observe correlation with stages, with tumor size and the extent of regional or distant metastatic invasion [21][22][23][24][25].…”