Identification of drug-resistant myeloid leukemic cells by measurement of DNA content, nuclear area, and detection of P-glycoprotein

Pattern-based sensing of triple negative breast cancer cells with dual-ligand cofunctionalized gold nanoclusters

Early detection of breast cancer is a critical component in patient prognosis and establishing effective therapy regimens. Here, we developed an easily accessible yet potentially powerful sensor to detect cancer cell targets by utilizing seven dual-ligand cofunctionalized gold nanoclusters (AuNCs) as both effective cell recognition elements and signal transducers. On the basis of this AuNC multichannel sensor, we have successfully distinguished healthy, cancerous and metastatic human breast cells with excellent reproducibility and high sensitivity. Triple negative breast cancer cells (TNBCs), which exhibit low expression of the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2, were identified. The high accuracy of the blind breast cell sample tests further validates the practical application of the sensor array. In addition, the versatility of the sensor array is further justified by identifying amongst distinct cell types, different cell concentrations and cell mixtures. Notably, the drug-resistant cancer cells can also be efficiently discriminated. Furthermore, the dual-ligand cofunctionalized AuNCs can efficiently differentiate different cells from the peripheral blood of tumor-free and tumor-bearing mice. Taken together, this fluorescent AuNCs based array provides a powerful cell analysis tool with potential applications in biomedical diagnostics.

Proportion of blasts with a clear halo around nucleoli at the end of induction therapy of acute myeloid leukemia correlates with achievement of complete remission, remission duration and relapse

Bone marrow aspirates from 60 patients with acute myeloid leukemia (AML) were investigated using 95% ethanol fixation Papanicolaou stained preparations. The blasts were grouped into those with a clear halo around nucleoli (BCHN) and those without a clear halo. The patients were classified into three groups according to the degree of persistent BCHN at the end of induction therapy: group 1, no BCHN; group 2, less than 1% BCHN; and group 3, 1% or more BCHN. All patients in groups 1 (17 cases) and 2 (12 cases), and 12 of 31 cases in group 3 achieved complete remission (CR). Of 17 patients in group 1, two underwent bone marrow transplantation and two died from infection. Of the 37 patients who achieved CR, relapse was observed in two of 13 patients in group 1, and in all patients in groups 2 and 3. As to the patients treated with N4-behenoyl-1-beta-D-arabinofuranosyl-cytosine + daunorubicin + 6-mercaptopurine + prednisolone (BHAC-DMP) protocol, the percentages and number of BCHN at the diagnosis of AML in group 1 were significantly lower than those of groups 2 and 3. The percentage and number of BCHN at the diagnosis of AML were significant factors for the achievement of CR and for the prediction of long-term outcome. The reduction of BCHN to less than 1% at the end of induction therapy is a good indicator for the achievement of CR, and the disappearance of BCHN is a useful target for a long-lasting first CR; conversely, the persistence of BCHN is a major adverse factor for relapse.

High reactivity of monoclonal antibody (TO73) with human malignant tumor cell line

The biological characteristics of a new monoclonal antibody (TO73) reacting with a vincristine-resistant human leukemic cell line (KY-VCR) were evaluated. Immunological and electron-immunological studies showed that TO73 reacted with the surface glycoprotein of KY-VCR. TO73 was found to have no effect on cell growth and intracellular uptake of vincristine. In human neoplastic cell lines, TO73 was found to react with 11 of 27 (41%) cell lines. With regard to de novo primary tumor with one exception, TO73 did not react with any of the examined primary tumor cells. The patient with TO73-positive leukemia died of induction failure due to drug resistance. Complete remission was achieved in the other leukemic patients. These results indicate that TO73 antigen may be associated with immortalization of tumor cells and poor prognosis in some cases.

Analysis of DNA content in multidrug-resistant cells by image and flow cytometry

Nuclear DNA content was assessed in multidrug-resistant (MDR) cells by image and flow cytometry. Two human MDR cell lines (K562-Dox and CEM-VLB) obtained by in vitro drug selection and overexpressing mdr1 gene were compared to their respective sensitive counterparts (K562 and CCRF-CEM) and to the MDR hamster LR73-R cell line obtained by transfection of mouse mdr1 cDNA. Both cell lines obtained by selection displayed a decreased DNA content, as measured by image cytometry after Feulgen staining, or by flow cytometry after staining with propidium iodide, ethidium bromide, or Hoechst 33342. This decrease was not accompanied by changes in cell cycle phase distribution of cells. Moreover, image cytometry of cells stained after various hydrolysis times in 5 M HCl indicated that MDR cells displayed the same hydrolysis kinetics and sensitivity as drug-sensitive cells with a well-preserved stoichiometry of the Feulgen reaction. LR73-R cells transfected with mdr1 cDNA exhibited only a very limited change in propidium iodide staining as compared with sensitive LR73 cells, suggesting that mdr1 gene overexpression alone could not account for the alterations in DNA content observed in the selected MDR cells.