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1.
The aim of the study was to assess the predictive value of MTTin vitro assay for evaluation of tumour cell resistance/sensitivity to cytotoxic drugs. We analyzed 105 samples of malignant cells of different origin. The study included patients with a diagnosis of acute and chronic lymphatic leukaemia, acute and chronic myeloid leukaemia, non-Hodgkin lymphoma, carcinoma of the lung, stomach and liver, rhabdomyosarcoma and breast carcinoma. The results demonstrate outstanding chemosensitivity in the majority of childhood acute lymphoblastic leukaemias, medium chemosensitivity of adult haematopoietic malignant diseases and chemoresistance of solid tumour cells. Our preliminary data suggest a good correlation betweenin vitro MTT assay and clinical curability of individual malignant diseases.Abbreviations ALL acute lymphoid leukaemia - AML acute myeloid leukaemia - CML chronic myeloid leukaemia - LCS50 50% leukaemic cell survival  相似文献   

2.
Treosulfan and busulphan are similar molecules, the former used in the treatment of ovarian cancer and the latter in chronic myelogenous leukaemia. We have used both in the differential staining cytotoxicity (DiSC) assay forin vitro drug sensitivity testing to aid in the choice of chemotherapy for individual patients.It was observed that occasionally the viability of control cells in one assay box was reduced compared with control cells in other boxes from the same assay. Treosulfan was suspected as the cause because cells throughout the microtitre box containing treosulfan had reduced viability in 28/62 (45%) experiments and in 9 of these, total kill of all cells in the box was observed.We tested the hypothesis that a metabolite of treosulfan might be the cause of this airborne cytotoxicity, and found that whilst 10 mg ml–1 of either methane sulphonic acid or tetrahydrofuran had no airborne cytotoxic effect, 1 mg ml–1 diepoxybutane killed over 95% of cells in all tubes in the same box.Treosulfan is another chemical (cf. azide, mafosfamide and possibly other cytotoxic agents) that can cause airborne cytotoxicity.Abbreviations ALL acute lymphoblastic leukaemia - AML acute non-lymphocytic leukaemia - CLL chronic lymphocytic leukaemia - NHL non-Hodgkin's lymphoma - DiSC assay differential staining cytotoxicity assay - MTT assay 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay - PBS phosphate buffered saline  相似文献   

3.
Chronic myelogenous leukaemia (CML) is a clonal myeloproliferative disorder. Recent evidence indicates that altered crosstalk between CML and mesenchymal stromal cells may affect leukaemia survival; moreover, vesicles released by both tumour and non‐tumour cells into the microenvironment provide a suitable niche for cancer cell growth and survival. We previously demonstrated that leukaemic and stromal cells establish an exosome‐mediated bidirectional crosstalk leading to the production of IL8 in stromal cells, thus sustaining the survival of CML cells. Human cell lines used are LAMA84 (CML cells), HS5 (stromal cells) and bone marrow primary stromal cells; gene expression and protein analysis were performed by real‐time PCR and Western blot. IL8 and MMP9 secretions were evaluated by ELISA. Exosomes were isolated from CML cells and blood samples of CML patients. Here, we show that LAMA84 and CML patients’ exosomes contain amphiregulin (AREG), thus activating epidermal growth factor receptor (EGFR) signalling in stromal cells. EGFR signalling increases the expression of SNAIL and its targets, MMP9 and IL8. We also demonstrated that pre‐treatment of HS5 with LAMA84 exosomes increases the expression of annexin A2 that promotes the adhesion of leukaemic cells to the stromal monolayer, finally supporting the growth and invasiveness of leukaemic cells. Leukaemic and stromal cells establish a bidirectional crosstalk: exosomes promote proliferation and survival of leukaemic cells, both in vitro and in vivo, by inducing IL8 secretion from stromal cells. We propose that this mechanism is activated by a ligand–receptor interaction between AREG, found in CML exosomes, and EGFR in bone marrow stromal cells.  相似文献   

4.
Summary Cryopreserved leukaemic blasts and remission non-T cells from 22 patients with acute leukaemia (15 lymphocytic, 7 non-lymphocytic) were tested as stimulators of autologous remission T cells and normal allogeneic T cells in primary and secondary MLC. In most cases the autologous response elicited by leukaemic cells was less than or equal to that elicited by remission non-T cells. However, T cells from 2 patients in long-standing first remission from ANLL displayed greater proliferation in response to leukaemic blasts than to remission non-T cells in both primary and secondary MLC. The results are suggestive of sensitization of these 2 patients to leukaemia-specific antigens, but other possible explanations are discussed. Abbreviations used: MLC, mixed leucocyte culture; ANLL, acute non-lymphocytic leukaemia; ALL, acute lymphoblastic leukaemia; AMLR, autologous mixed lymphocyte reaction; NK cells, natural killer cells; MNC, mononuclear cells  相似文献   

5.
Spleen and bone marrow cells from normal and leukaemic RFM mice have been assayed for numbers of colony forming cells in soft agar (CFU-C). The fluctuations in CFU-C yield observed during the development of myeloid leukaemia are similar to the results from in vitro experiments set up to test a model, and are not incompatible with the idea that interaction between normal and leukaemic cells may modify the yield of CFU-C under the present conditions of culture. Colonies grown from leukaemic spleen and bone marrow cells appear to be derived from the residual population of normal haemopoietic cells within the leukaemic mouse.  相似文献   

6.
 T cell clones (CD4+CD8TCRαβ+γδ) derived from bone marrow transplant recipients were stimulated with phytohaemagglutinin (PHA) +interleukin-2 (IL-2) in the presence of irradiated (50 Gy) peripheral blood mononuclear cells (PBMC) derived from acute leukaemia patients(leukaemic PBMC containing more than 95% blast cells). Leukaemic PBMC could function as accessory cells during mitogenic T cell activation resulting in both T cell proliferation and a broad T cell cytokine response [IL-3, IL-4, IL-10, granulocyte/macrophage-colony-stimulating factor (GM-CSF) tumour necrosis factor α (TNFα) and interferon γ (IFNγ) secretion]. Blockade of IL-1 effects by adding IL-1 receptor antagonist together with PHA+IL-2+leukaemia blasts increased T cell proliferation, whereas IL-6-neutralizing antibodies did not alter T cell proliferation. A qualitatively similar T cell cytokine response and a similar cytokine profile (highest levels detected for GM-CSF and IFNγ) were detected when normal polyclonal T cell lines were stimulated with PHA in the presence of non-irradiated leukaemic PBMC. When leukaemic PBMC derived from 18 acute myelogenous leukaemia patients were cultured with PHA and cells from a polyclonal T cell line, increased concentrations of the T cell cytokines IFNγ and IL-4 were detected for all patients. We conclude that T cell activation resulting in proliferation and a broad cytokine response can take place in the presence of excess acute myelogenous leukaemia blasts. Received: 30 November 1995 / Accepted: 9 January 1996  相似文献   

7.
Neoplastic cells frequently have an increased number of transferrin receptors. Coupling transferrin to an anti-neoplastic drug has the potential to overcome multidrug resistance (MDR). The purpose of this study was to examine the distribution and action of doxorubicin-transferrin conjugate (DOXTRF) in a leukaemia cell line (HL60), a multidrug-resistant leukaemia cell line (HL60ADR) and a normal tissue cell line (human fibroblasts). The intracellular accumulation of DOX and DOX-TRF was monitored by direct fluorescence. More DOX-TRF than free DOX was delivered to the tumour cells, and consecutively the levels of DNA double-strand breaks and apoptosis increased even in the multidrug-resistant cell line. In the normal tissue cell line, DOX-TRF did not accumulate, and therefore, the levels of DNA double-strand breaks and apoptosis did not increase. Cell viability was determined using the MTT assay. The IC50 for DOX-TRF was lower than the IC50 value for the free drug in both leukaemia cell lines. The IC50 values for the HL60 cells were 0.08 μM for DOX and 0.02 μM for DOX-TRF. The IC50 values for HL60ADR cells were 7 μM for DOX and 0.035 μM for DOX-TRF. In conclusion, DOX-TRF was able to overcome MDR in the leukaemia cell lines while having only a very limited effect on normal tissue cells.  相似文献   

8.
Acquired chemoresistance represents a major obstacle in cancer treatment, the underlying mechanism of which is complex and not well understood. MiR‐425‐5p has been reported to be implicated tumorigenesis in a few cancer types. However, its role in regulating chemoresistance has not been investigated in colorectal cancer (CRC) cells. Microarray analysis was performed in isogenic chemosensitive and chemoresistant HCT116 cell lines to identify differentially expressed miRNAs. miRNA quantitative real‐time PCR was used to detect miR‐425‐5p expression levels between drug resistant and parental cancer cells. MiR‐425‐5p mimic and inhibitor were transfected, followed by CellTiter‐Glo® assay to examine drug sensitivity in these two cell lines. Western Blot and luciferase assay were performed to investigate the direct target of miR‐425‐5p. Xenograft mouse models were used to examine in vivo function of miR‐425‐5p. Our data showed that expression of miR‐425‐5p was significantly up‐regulated in HCT116‐R compared with parental HCT116 cells. Inhibition of miR‐425‐5p reversed chemoresistance in HCT116‐R cells. Programmed cell death 10 (PDCD10) is the direct target of miR‐425‐5p which is required for the regulatory role of miR‐425‐5p in chemoresistance. MiR‐425‐5p inhibitor sensitized HCT116‐R xenografts to chemo drugs in vivo. Our study demonstrated that miR‐425‐5p regulates chemoresistance of CRC cells by modulating PDCD10 expression level both in vitro and in vivo. MiR‐425‐5p may represent a new therapeutic target for the intervention of CRC.  相似文献   

9.
Introduction –  The chemical and pharmaceutical studies carried out on species from Polygonum L. genus showed biological activity both of the extracts and the components isolated from them. These results were the impulse to examine Polygonum amphibium L. Objective –  The aim of this study was the isolation of active components from methanol extract and the determination of their cytotoxic effect on human leukaemic cell lines. Methodology  – Three flavonoid components from butanol soluble fractions of methanol extract by CC and PC preparative chromatography were isolated. Their structures were established on the basis of 1H, 13C and correlation (DEPT, H‐H, COSY, HMQC, HMBC) NMR, UV and FAB‐MS spectroscopic techniques. The evaluation of the anti‐leukaemic activities of 1 and 2 against Jurkat and HL60 cell lines was carried out in vitro using annexin V fluorescence assay. Results  – Two new flavonoid glucuronides, quercetin‐3‐O‐β‐glucuronide ( 1 ) and quercetin‐3‐O‐α‐rhamnosyl‐(1 → 2)‐β‐glucuronide ( 2 ), and kaempferol‐3‐O‐α‐rhamnosyl‐(1 → 2)‐β‐glucuronide ( 3 ), were isolated from Polygonum amphibium L. It was demonstrated that the glucuronides of quercetin are able to induce apoptosis in the tested human leukaemic cells. These compounds penetrate through cytoplasm to the cellular nucleus of the cultured cells, and give intensive apoptotic responses in the stimulated leukaemic cells. The number of apoptotic cells increased with the concentration (1 nm to 10 µm ) of 1 or 2 and periods of exposure (1–3 days). Conclusion  – Compounds 1 and 2 may be considered good candidates for leukaemia chemotherapeutic agents. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

10.
The objectives of this study are to enhance cellular accumulation of gemcitabine with chitosan/glyceryl monooleate (GMO) nanostructures, and to provide significant increase in cell death of human pancreatic cancer cells in vitro. The delivery system was prepared by a multiple emulsion solvent evaporation method. The nanostructure topography, size, and surface charge were determined by atomic force microscopy (AFM), and a zetameter. The cellular accumulation, cellular internalization and cytotoxicity of the nanostructures were evaluated by HPLC, confocal microscopy, or MTT assay in Mia PaCa-2 and BxPC-3 cells. The average particle diameter for 2% and 4% (w/w) drug loaded delivery system were 382.3 ± 28.6 nm, and 385.2 ± 16.1 nm, respectively with a surface charge of +21.94 ± 4.37 and +21.23 ± 1.46 mV. The MTT cytotoxicity dose-response studies revealed the placebo at/or below 1 mg/ml has no effect on MIA PaCa-2 or BxPC-3 cells. The delivery system demonstrated a significant decrease in the IC50 (3 to 4 log unit shift) in cell survival for gemcitabine nanostructures at 72 and 96 h post-treatment when compared with a solution of gemcitabine alone. The nanostructure reported here can be resuspended in an aqueous medium that demonstrate increased effective treatment compared with gemcitabine treatment alone in an in vitro model of human pancreatic cancer. The drug delivery system demonstrates capability to entrap both hydrophilic and hydrophobic compounds to potentially provide an effective treatment option in human pancreatic cancer.  相似文献   

11.
Cryopreserved AML cells from eight patients when thawed retained radioactive chromium better when they were labelled with the chromium after they had first been grown in short-term in vitro culture to establish proliferative cell populations. Such labelled cells are required for immunological studies of patients with acute leukaemia, so the ability to proliferate is a new test, more relevant to immunology than other available methods, for designing optimum cryopreservation conditions for these AML cells.Fifty-six populations of cryopreserved AML cells (from 53 patients) were cultured in vitro, and the growth pattern of the cell populations fell into three classes: (i) rapid death of some of the cells followed by proliferative growth and an increase in cell number (14 populations); (ii) cultures in which the cell number remained constant after an initial fall (6 populations), and (iii) rapid death of all the cells (36 populations). Although morphological studies showed maturation of some of the leukaemia blast cells into polymorphs during proliferative culture, leukaemia cells persisted in all cultures. In addition, in two cases it was shown that cells from the cultures had the same karyo-type abnormalities as those found in the donor's bone marrow and so it was concluded that the proliferating cells were of leukaemic origin rather than from normal cells.Using the proliferative capacity of AML cells from nine patients as a test of factors influencing cryopreservation efficiency, it was shown that the longer AML cells were kept in DMSO (5, 7.5, and 10%) for periods of up to 120 min prior to controlled slow freezing (+4 to −30 °C at l °C/min), the poorer was their capacity to grow.  相似文献   

12.
The behaviour of normal haemopoietic stem cells of the bone marrow during the development of the acute transferable rat leukaemia, L 5222, has been investigated. The granulopoietic committed stem cells, measured by the in vitro colony technique, showed a marked decrease to less than half normal levels. Pluripotent stem cells included in the small lymphocytes of the bone marrow, and labelled with 3H-thymidine by the complete labelling method, showed only a modest decrease in number and an unchanged labelling intensity. The results suggest that in this leukaemia the pluripotent stem cells may be affected in such a way that they are unable to react by proliferation to the depletion of the succeeding cell compartments. This might be due to inhibition by leukaemic cells or to a disturbed feedback regulation between the committed and pluripotent stem cell compartments.  相似文献   

13.
Acute myeloid leukaemia (AML) with chromosomal rearrangements involving the H3K4 methyltransferase mixed-lineage leukaemia (MLL) is an aggressive subtype with low overall survival. Bortezomib (Bort) is first applied in multiple myeloma. However, whether bort possesses anti-self-renewal and leukemogenesis of leukaemia stem cell (LSC) in AML with MLL rearrangements is still unclear. Here, we found that bort suppressed cell proliferation and decreased colony formation in human and murine leukaemic blasts. Besides, bort reduced the frequency and function of LSC, inhibited the progression, and extended the overall survival in MLL-AF9 (MF9) -transformed leukaemic mice. Furthermore, bort decreased the percentage of human LSC (CD34+CD38-) cells and extended the overall survival in AML blasts-xenografted NOD/SCID-IL2Rγ (NSG) mice. Mechanistically, cyclin dependent kinase 6 (CDK6) was identified as a bort target by RNA sequencing. Bort reduced the expressions of CDK6 by inhibiting NF ĸB recruitment to the promoter of CDK6, leading to the abolishment of NF ĸB DNA-binding activity for CDK6 promoter. Overexpression of CDK6 partially rescued bort-induced anti-leukemogenesis. Most importantly, bort had little side-effect against the normal haematological stem and progenitor cell (HSPC) and did not affect CDK6 expression in normal HSPC. In conclusion, our results suggest that bort selectively targets LSC in MLL rearrangements. Bort might be a prospective drug for AML patients bearing MLL rearrangements.  相似文献   

14.
Human leukaemic cell specimens were obtained from patients and directly plated into soft agar (t= 0) or cultured for 1 week in liquid phase and then plated in soft agar. Growth for 1 week in liquid phase allowed the clonal growth in agar of leukaemic specimens which were unable to clone at t= 0. Clonal growth after liquid culture consisted of the usual leukaemic type of cluster-colonies, growth of a new type of ‘syncytial’ cell colony or a mixture of colony types. In addition, marrow from a patient with acute lymphocytic leukaemia produced normal-appearing colonies after 1 week of growth in liquid phase. These studies suggest a similarity in the growth requirements of some leukaemic cells and normal CFUd cells.  相似文献   

15.
 Normal peripheral blood mononuclear cells (PBMC responders) were cultured together with non-irradiated allogeneic PBMC (more than 95% leukaemia blasts) derived from patients with acute leukaemia (referred to as leukaemic PBMC stimulators). Cytokine secretion was determined as cytokine concentrations in supernatants. Both normal PBMC and enriched CD4+ and CD8+ T cells responded to allostimulation with interferon (IFNγ) secretion. Interleukin-1 (IL-1) receptor antagonist and IL-2-neutralizing antibodies decreased IFNγ secretion. Exogenous IL-1β, IL-2 and IL-7 increased allostimulated IFNγ secretion, whereas decreased levels were seen in the presence of IL-6, IL-10 and granulocyte-colony-stimulating factor (G-CSF). During allorecognition IFNγ -neutralizing antibodies decreased acute myelogenous leukaemia (AML) blast secretion of G-CSF. We conclude that (i) both CD4+ and CD8+ T cells show allostimulated cytokine secretion in response to allogeneic stimulator cells containing a dominating population of native, cytokine-secreting leukaemia blasts, and (ii) IFNγ released during this response can modulate the function of allogeneic AML blasts. Received: 4 June 1996 / Accepted: 15 October 1996  相似文献   

16.
Accumulating data suggest that cancers contain a fraction of cells called cancer stem cells (CSCs), that may be responsible for upkeep and relapses of disease. In experimental settings, CSCs are regarded as most effective at tumour initiation in in vivo assays. Since the first isolation of cancer stem cells from acute myeloid leukaemia in 1994, cancer stem cells have been identified in human solid tumours and they have also been found in the established cell lines, based on ability of CSCs to form in vitro colonies of a specific morphology, called holoclones. Our study examined the ability of a mouse sarcoma cell line, derived from a lung metastasis of a BALB/c mouse and established as a stably growing line (L1), to produce holoclones in vitro. We aimed to verify a stemness signature of the holoclone cells. The L1 cell line was found to form holoclone colonies in vitro, which were shown to contain a percentage of CSC‐like cells. A fraction of the L1 cells was able to repopulate the original cell line, and presented an increased clonogenic and metastatic potential (18th passage). In addition, MTT assay and flow cytometry of the side population fraction revealed that these cells were more resistant to chemotherapeutic drugs than the original cell line, and over‐expressed the anti‐apoptotic genes, GRP78 and GADD153. We conclude that mouse L1 sarcoma cell line contains CSC‐like cells.  相似文献   

17.
Chemoresistance is a common occurrence during advanced or recurrent cervical cancer therapy when treated by conventional treatment, platinum‐based chemotherapy. This study aimed to investigate the effect and underlying mechanism of tanshinone I on attenuating proliferation and chemoresistance of cervical cancer cells. In cervical cancer cells, cell proliferation was examined by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT), cell count, and soft‐agar colony‐formation assay. rVista analysis and luciferase reporter assay were used to explore the upstream regulator of KRAS, and the expression levels of key genes were also detected. Western blot analysis showed that tanshinone I significantly suppressed KRAS expression and inhibited AKT phosphorylation. rVista analysis and luciferase reporter assay demonstrated that ELK1 can binds directly to KRAS promoter and positively regulates KRAS expression. MTT assay showed that KRAS or ELK1 overexpression significantly attenuated the suppressive effects of tanshinone I on HeLa cells proliferation. In addition, tanshinone I recovered the cisplatin sensitivity of HeLa CR cells, whereas KRAS or ELK1 overexpression significantly inhibited this phenomenon. Our results suggested that tanshinone I had anticancer effects on cervical cancer cells via inhibiting ELK1 and downregulating KRAS‐AKT axis, which subsequently suppressed the proliferation and cisplatin resistance of cervical cancer cells.  相似文献   

18.
Despite novel therapy regimens and extensive research, chemoresistance remains a challenge in leukemia treatment. Of note, recent studies revealed lysosomes as regulators of cell death and chemotherapy response, suggesting this organelle is a novel target for chemosensitization. Interestingly, drug-resistant VCR-R CEM acute lymphoblastic leukemia (ALL) cells have an increased expression of the lysosomal cation channel Two-Pore-Channel 2 (TPC2) compared to drug-naïve CCRF-CEM ALL cells. Concurrently, knockout (KO) of TPC2 sensitized drug-resistant VCR-R CEM cells to treatment with cytostatics. The chemosensitizing effect could be confirmed in several cell lines as well as in heterogeneous, patient-derived xenograft ALL cells, using the pharmacological TPC2 inhibitors naringenin and tetrandrine. We reveal that a dual mechanism of action mediates chemo sensitization by loss of lysosomal TPC2 function. First, because of increased lysosomal pH, lysosomal drug sequestration is impaired, leading to an increased nuclear accumulation of doxorubicin and hence increased DNA damage. Second, lysosomes of TPC2 KO cells are more prone to lysosomal damage as a result of morphological changes and dysregulation of proteins influencing lysosomal stability. This leads to induction of lysosomal cell death (LCD), evident by increased cathepsin B levels in the cytosol, truncation of pro-apoptotic Bid, as well as the reversibility of cell death by co-treatment with the cathepsin B inhibitor CA-074Me in TPC2 KO cells. In summary, this study establishes TPC2 as a novel, promising, druggable target for combination therapy approaches in ALL to overcome chemoresistance, which could be exploited in the clinic in the future. Additionally, it unravels LCD signaling as an important death-inducing component upon loss of TPC2 function.Subject terms: Acute lymphocytic leukaemia, Acute lymphocytic leukaemia, Apoptosis  相似文献   

19.
Abstract

The current study aimed to develop PEGylated trimethyl chitosan (TMC) coated emulsomes (EMs) conjugated with octreotide for targeted delivery of sorafenib to hepatocellular carcinoma cells (HCC) of HepG2. Sorafenib loaded TMC coated EMs were prepared by the emulsion evaporation method and characterized concerning particle size, zeta potential, drug encapsulation efficiency, and in vitro drug release. Synthesized EMs were then conjugated to octreotide. The cytotoxicity of the targeted and non-targeted EMs was determined by cellular uptake and MTT assay on HepG2 cell. Cell cycle assay was also studied using flow cytometry. The results showed the optimized EMs had the particle size of 127?nm, zeta potential of ?5.41?mV, loading efficiency of 95%, and drug release efficiency of 62% within 52?h. Octreotide was attached efficiently to the surface of EMs as much as 71%. MTT assay and cellular uptake studies showed that targeted EMs had more cytotoxicity than free sorafenib and non-targeted EMs. Cell cycle analyses revealed that there was a significant more accumulation of targeted EMs treated HepG2 cells in the G1 phase than free sorafenib and non-targeted EMs. The results indicate that designed EMs may be promising for the treatment of hepatocellular carcinoma.  相似文献   

20.
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