Early responses to chemotherapy detected by pulse cytophotometry.

DNA/cell distributions were recorded by automated cytofluorometry (=pulse cytophotometry) in bone-marrow aspirates of leukaemia and lymphosarcoma patients subjected to chemotherapy. In most cases, early perturbations in DNA/cell histographs were observed, characteristically reflecting the known mode of action of the drugs. These changes in general preceded the clinical observation of drug response. In a series of 23 measurements in 19 patients, a positive correlation between early cytophotometric changes and clinical effects of chemotherapy was observed in 17 patients. Five patients were negative for both cytophotometric and clinical reactions and one patient was probably false-positive. The validity of the assay for early detection of drug resistance in acute leukaemia and related diseases is discussed

The effect of gastrectomy on regorafenib exposure and progression-free survival in patients with advanced gastrointestinal stromal tumours

Contains fulltext : 208932.pdf (publisher's version ) (Open Access)AIMS: We investigated whether major gastrectomy influences the plasma exposure of regorafenib and treatment outcome. METHODS: Efficacy and pharmacokinetic data from 133 gastrointestinal stromal tumour patients included in a phase III trial were analysed. Patients were subdivided into 2 groups according to the extent of the gastrectomy (no/nonsignificant gastrectomy and major gastrectomy). Progression-free survival (PFS) on regorafenib was measured and regorafenib and its pharmacological active metabolites plasma exposure were measured. RESULTS: A total of 133 patient were included, of whom 27 underwent major gastrectomy. In patients with no/nonsignificant gastrectomy the median PFS was 145 (interquartile range 43-281) days. The PFS in patients with a major gastrectomy was 172 (interquartile range 57-280) days. Regorafenib pharmacokinetic samples were collected in 80 patients of which 19 patients with a major gastrectomy and 61 patients with no/nonsignificant gastric surgery. The average +/- standard deviation total concentration of regorafenib including the metabolites M-2 and M-5 was 6.9 +/- 1.53 mumol/L and 6.7 +/- 1.56 mumol/L in patient with major gastrectomy and no/nonsignificant gastrectomy respectively. CONCLUSION: Our study shows that major gastrectomy did not influence plasma exposure of regorafenib and metabolites. In addition, no difference in PFS between the subgroups was seen

Energy-Filtering Transmission Electron Microscopy as a Tool for Structural and Compositional Analysis of Isolated Ferritin Particles

Structural and compositional analysis of isolated horse-spleen ferritin particles was performed by energy filtering transmission electron microscopy (EFTEM). Ferritin particles were collected in ultrathin (2 nm thick) chromium films and analyzed without any additional stain by electron energy-loss spectroscopy (EELS) for iron and carbon and by electron-spectroscopic imaging (ESI) for carbon. The ultrastructure of the proteinaceous shell of the ferritin particle, as obtained by the carbon net-intensity electron spectroscopical and carbon concentration-distribution images, was qualitatively compared to the structure as acquired by a negative-staining procedure. Quantitative analysis of the number of carbon atoms in the ferritin-shell proteins was carried out through an ESI-acquisition protocol and processing procedure with calibrated attenuation filters in the optical path to the TV camera. This procedure included images acquired with calibrated attenuation filters for the compensation of shading and the non-linear performance of the TV camera used in the analytical part of the procedure. A new ESI-Spectra program is proposed that allows element-related spectra to be generated at any place and with any frame size in a contrast-sensitive or other type of image present on the computer monitor screen

Kinome and mRNA expression profiling of high-grade osteosarcoma cell lines implies Akt signaling as possible target for therapy

Background: High-grade osteosarcoma is a primary malignant bone tumor mostly occurring in adolescents and young adults, with a second peak at middle age. Overall survival is approximately 60%, and has not significantly increased since the introduction of neoadjuvant chemotherapy in the 1970s. The genomic profile of high-grade osteosarcoma is complex and heterogeneous. Integration of different types of genome-wide data may be advantageous in extracting relevant information from the large number of aberrations detected in this tumor. Methods: We analyzed genome-wide gene expression data of osteosarcoma cell lines and integrated these data with a kinome screen. Data were analyzed in statistical language R, using LIMMA for detection of differential expression/phosphorylation. We subsequently used Ingenuity Pathways Analysis to determine deregulated pathways in both data types. Results: Gene set enrichment indicated that pathways important in genomic stability are highly deregulated in these tumors, with many genes showing upregulation, which could be used as a prognostic marker, and with kinases phosphorylating peptides in these pathways. Akt and AMPK signaling were identified as active and inactive, respectively. As these pathways have an opposite role on mTORC1 signaling, we set out to inhibit Akt kinases with the allosteric Akt inhibitor MK-2206. This resulted in inhibition of proliferation of osteosarcoma cell lines U-2 OS and HOS, but not of 143B, which harbors a KRAS oncogenic transformation. Conclusions: We identified both overexpression and hyperphosphorylation in pathways playing a role in genomic stability. Kinome profiling identified active Akt signaling, which could inhibit proliferation in 2/3 osteosarcoma cell lines. Inhibition of PI3K/Akt/mTORC1 signaling may be effective in osteosarcoma, but further studies are required to determine whether this pathway is active in a substantial subgroup of this heterogeneous tumor

Genetic alterations on chromosome 16 and 17 are important features of ductal carcinoma in situ of the breast and are associated with histologic type

We analysed the involvement of known and putative tumour suppressor- and oncogene loci in ductal carcinoma in situ (DCIS) by microsatellite analysis (LOH), Southern blotting and comparative genomic hybridization (CGH). A total of 78 pure DCIS cases, classified histologically as well, intermediately and poorly differentiated, were examined for LOH with 76 markers dispersed along all chromosome arms. LOH on chromosome 17 was more frequent in poorly differentiated DCIS (70%) compared to well-differentiated DCIS (17%), whereas loss on chromosome 16 was associated with well- and intermediately differentiated DCIS (66%). For a subset we have done Southern blot- and CGH analysis. C-erbB2/neu was amplified in 30% of poorly differentiated DCIS. No amplification was found of c-myc, mdm2, bek, flg and the epidermal growth factor (EGF)-receptor. By CGH, most frequent alterations in poorly differentiated DCIS were gains on 8q and 17q22–24 and deletion on 17p, whereas in well-differentiated DCIS amplification on chromosome 1q and deletion on 16q were found. In conclusion, our data indicates that inactivation of a yet unknown tumour suppressor gene on chromosome 16q is implicated in the development of most well and intermediately differentiated DCIS whereas amplification and inactivation of various genes on chromosome 17 are implicated in the development of poorly differentiated DCIS. Furthermore these data show that there is a genetic basis for the classification of DCIS in a well and poorly differentiated type and support the evidence of different genetic routes to develop a specific type of carcinoma in situ of the breast. © 1999 Cancer Research Campaig