941 resultados para Liver cancer stem cell
Resumo:
Since the early 1980s high dose chemotherapy with autologous hematopoietic stem cell support was adopted by many oncologists as a potentially curative option for solid tumors, supported by a strong rationale from laboratory studies and apparently convincing results of early phase II studies. As a result, the number and size of randomized trials comparing this approach with conventional chemotherapy initiated (and often abandoned before completion) to prove or disprove its value was largely insufficient. In fact, with the possible exception of breast carcinoma, the benefit of a greater escalation of dose of chemotherapy with stem cell support in solid tumors is still unsettled and many oncologists believe that this approach should cease. In this article, we critically review and comment on the data from studies of high dose chemotherapy so far reported in adult patients with small cell lung cancer, ovarian cancer, germ cell tumors and sarcomas.
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Caspofungin at standard dose was evaluated as first-line monotherapy of mycologically documented probable/proven invasive aspergillosis (IA) (unmodified European Organisation for Research and Treatment of Cancer/Mycosis Study Group criteria) in allogeneic hematopoietic SCT patients. The primary efficacy end point was complete or partial response at end of caspofungin treatment. Response at week 12, survival and safety were additional end points. Enrollment was stopped prematurely because of low accrual, with 42 enrolled and 24 eligible, giving the study a power of 85%. Transplant was from unrelated donors in 16 patients; acute or chronic GVHD was present in 15. In all, 12 patients were neutropenic (<500/microl) at baseline, 10 received steroids and 16 calcineurin inhibitors or sirolimus. Median duration of caspofungin treatment was 24 days. At the end of caspofungin therapy, 10 (42%) patients had complete or partial response (95% confidence interval: 22-63%); 1 (4%) and 12 (50%) had stable and progressing disease, respectively; one was not evaluable. At week 12, eight patients (33%) had complete or partial response. Survival rates at week 6 and 12 were 79 and 50%, respectively. No patient had a drug-related serious adverse event or discontinued because of toxicity. Caspofungin first-line therapy was effective and well tolerated in allogeneic hematopoietic SCT patients with mycologically documented IA.
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BACKGROUND: The relationship between predictive proteins and tumors presenting cancer stem cells (CSCs) profiles in oral tumors is still poorly understood. This study aims to identify the relationship between topoisomerases I, II alpha, and III alpha and putative CSCs immunophenotype in oral squamous cell carcinoma (OSCC) and determine its influence on prognosis. METHODS: The following data were retrieved from 127 patients: age, gender, primary anatomic site, smoking and alcohol intake, recurrence, metastases, histologic classification, treatment, and survival. An immunohistochemical study for topoisomerases I, II alpha, and III alpha was performed in a tissue microarray containing 127 paraffin blocks of OSCCs. RESULTS: In univariate analysis, topoisomerases expression showed significant differences according to CSCs profiles and p53 immunoexpression, but not with survival. Topoisomerases II alpha and III alpha also showed significant relationship with lymph node metastasis. The multivariate test confirmed these associations. CONCLUSIONS: The results that all topoisomerases correlates with OSCC CSCs may indicate a role for topoisomerases in head and neck carcinogenesis. Notwithstanding, it is plausible that other members of topoisomerases family could represent novel therapeutical targets in oral squamous cell carcinoma. J Oral Pathol Med (2012) 41: 762-768
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High serum levels of Interleukin-6 (IL-6) correlate with poor outcome in breast cancer patients. However no data are available on the relationship between IL-6 and stem/progenitor cells which may fuel the genesis of breast cancer in vivo. Herein, we address this issue in mammospheres (MS), multi-cellular structures enriched in stem/progenitor cells of the mammary gland, and also in MCF-7 breast cancer cells. We show that MS from node invasive breast carcinoma tissues express IL-6 mRNA at higher levels than MS from matched non-neoplastic mammary glands. We find that IL-6 mRNA is detectable only in basal-like breast carcinoma tissues, an aggressive variant showing stem cell features. Our results reveal that IL-6 triggers a Notch-3-dependent up-regulation of the Notch ligand Jagged-1, whose interaction with Notch-3 promotes the growth of MS and MCF-7 derived spheroids. Moreover, IL-6 induces a Notch-3-dependent up-regulation of the carbonic anhydrase IX gene, which promotes a hypoxia-resistant/invasive phenotype in MCF-7 cells and MS. Finally, an autocrine IL-6 loop relies upon Notch-3 activity to sustain the aggressive features of MCF-7-derived hypoxia-selected cells. In conclusion, our data support the hypothesis that IL-6 induces malignant features in Notch-3 expressing, stem/progenitor cells from human ductal breast carcinoma and normal mammary gland.
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Inhibitor of differentiation 1 (ID1) plays a role in cellular differentiation, proliferation, angiogenesis and tumor invasion. As shown recently, ID1 is positively regulated by the tyrosine kinase SRC in lung carcinoma cell lines and with that appears as a potential new therapeutic target in non-small cell carcinoma (NSCLC). To substantiate this hypothesis we examined ID1, SRC and matrix metalloproteinase-9 (MMP-9) immunohistochemically in human NSCLC specimens.
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Thrombotic microangiopathy (TMA) has multiple etiologies. In the four disorders described in this review, the primary organ involved is the kidney. Drug-associated TMA can be an acute, immune-mediated disorder or the result of gradual, dose-dependent toxicity. TMA may occur in patients with advanced HIV infection, possibly mediated by angio-invasive infections. TMA following allogeneic hematopoietic stem cell transplantation may also be caused by drug toxicity; the pathogenesis may involve inhibition of vascular endothelial cell growth factor in renal podocytes. Malignancies of many types with systemic microvascular involvement may cause TMA. Recognition that these syndromes may mimic TTP is important to provide appropriate management and to avoid the inappropriate use of plasma exchange treatment.
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We isolated a stem cell subpopulation from human lung cancer A549 cells using FACS/Hoechst 33342. This side population (SP), which comprised 24% of the total cell population, totally disappeared after treatment with the selective ABCG 2 inhibitor fumitremorgin C. In a repopulation study, isolated SP and non-SP cells were each able to generate a heterogeneous population of SP and non-SP cells, but this repopulation occurred more rapidly in SP cells than non-SP. An MTT assay and cell cycle distribution analysis reveal a similar profile between SP and non-SP groups. However, in the presence of doxorubicin (DOX) and methotrexate (MTX), SP cells showed significantly lower Annexin V staining when compared to non-SP cells. Taken together, these results demonstrate that SP cells have an active regeneration capacity and high anti-apoptotic activity compared with non-SP cells. Furthermore, our GeneChip data revealed a heightened mRNA expression of ABCG2 and ABCC2 in SP cells. Overall these data explain why the SP of A549 has a unique ability to resist DOX and MTX treatments. Therefore, we suggest that the expression of the ABCG2 transporter plays an important role in the multidrug resistance phenotype of A549 SP cells.
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The reciprocal interaction between cancer cells and the tissue-specific stroma is critical for primary and metastatic tumor growth progression. Prostate cancer cells colonize preferentially bone (osteotropism), where they alter the physiological balance between osteoblast-mediated bone formation and osteoclast-mediated bone resorption, and elicit prevalently an osteoblastic response (osteoinduction). The molecular cues provided by osteoblasts for the survival and growth of bone metastatic prostate cancer cells are largely unknown. We exploited the sufficient divergence between human and mouse RNA sequences together with redefinition of highly species-specific gene arrays by computer-aided and experimental exclusion of cross-hybridizing oligonucleotide probes. This strategy allowed the dissection of the stroma (mouse) from the cancer cell (human) transcriptome in bone metastasis xenograft models of human osteoinductive prostate cancer cells (VCaP and C4-2B). As a result, we generated the osteoblastic bone metastasis-associated stroma transcriptome (OB-BMST). Subtraction of genes shared by inflammation, wound healing and desmoplastic responses, and by the tissue type-independent stroma responses to a variety of non-osteotropic and osteotropic primary cancers generated a curated gene signature ("Core" OB-BMST) putatively representing the bone marrow/bone-specific stroma response to prostate cancer-induced, osteoblastic bone metastasis. The expression pattern of three representative Core OB-BMST genes (PTN, EPHA3 and FSCN1) seems to confirm the bone specificity of this response. A robust induction of genes involved in osteogenesis and angiogenesis dominates both the OB-BMST and Core OB-BMST. This translates in an amplification of hematopoietic and, remarkably, prostate epithelial stem cell niche components that may function as a self-reinforcing bone metastatic niche providing a growth support specific for osteoinductive prostate cancer cells. The induction of this combinatorial stem cell niche is a novel mechanism that may also explain cancer cell osteotropism and local interference with hematopoiesis (myelophthisis). Accordingly, these stem cell niche components may represent innovative therapeutic targets and/or serum biomarkers in osteoblastic bone metastasis.
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Background: Prostate tumor heterogeneity is a major factor in disease management. Heterogeneity could be due to multiple cancer cell types with distinct gene expression. Of clinical importance is the so-called cancer stem cell type. Cell type-specific transcriptomes are used to examine lineage relationship among cancer cell types and their expression similarity to normal cell types including stem/progenitor cells. Methods: Transcriptomes were determined by Affymetrix DNA array analysis for the following cell types. Putative prostate progenitor cell populations were characterized and isolated by expression of the membrane transporter ABCG2. Stem cells were represented by embryonic stem and embryonal carcinoma cells. The cancer cell types were Gleason pattern 3 (glandular histomorphology) and pattern 4 (aglandular) sorted from primary tumors, cultured prostate cancer cell lines originally established from metastatic lesions, xenografts LuCaP 35 (adenocarcinoma phenotype) and LuCaP 49 (neuroendocrine/small cell carcinoma) grown in mice. No detectable gene expression differences were detected among serial passages of the LuCaP xenografts. Results: Based on transcriptomes, the different cancer cell types could be clustered into a luminal-like grouping and a non-luminal-like (also not basal-like) grouping. The non-luminal-like types showed expression more similar to that of stem/progenitor cells than the luminal-like types. However, none showed expression of stem cell genes known to maintain stemness. Conclusions: Non-luminal-like types are all representatives of aggressive disease, and this could be attributed to the similarity in overall gene expression to stem and progenitor cell types.
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The presence of stem cell characteristics in glioma cells raises the possibility that mechanisms promoting the maintenance and self-renewal of tissue specific stem cells have a similar function in tumor cells. Here we characterized human gliomas of various malignancy grades for the expression of stem cell regulatory proteins. We show that cells in high grade glioma co-express an array of markers defining neural stem cells (NSCs) and that these proteins can fulfill similar functions in tumor cells as in NSCs. However, in contrast to NSCs glioma cells co-express neural proteins together with pluripotent stem cell markers, including the transcription factors Oct4, Sox2, Nanog and Klf4. In line with this finding, in high grade gliomas mesodermal-and endodermal-specific transcription factors were detected together with neural proteins, a combination of lineage markers not normally present in the central nervous system. Persistent presence of pluripotent stem cell traits could only be detected in solid tumors, and observations based on in vitro studies and xenograft transplantations in mice imply that this presence is dependent on the combined activity of intrinsic and extrinsic regulatory cues. Together these results demonstrate a general deregulated expression of neural and pluripotent stem cell traits in malignant human gliomas, and indicate that stem cell regulatory factors may provide significant targets for therapeutic strategies.
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Acute promyelocytic leukemia (APL) is characterized by a block in differentiation and accumulation of promyelocytes in the bone marrow and blood. The majority of APL patients harbor the t(15: 17) translocation leading to expression of the fusion protein promyelocytic-retinoic acid receptor alpha. Treatment with retinoic acid leads to degradation of promyelocytic-retinoic acid receptor alpha protein and disappearance of leukemic cells; however, 30% of APL patients relapse after treatment. One potential mechanism for relapse is the persistence of cancer ""stem"" cells in hematopoietic organs after treatment. Using a novel sorting strategy we developed to isolate murine myeloid cells at distinct stages of differentiation, we identified a population of committed myeloid cells (CD34(+), c-kit(+), Fc gamma RIII/II(+), Gr1(int)) that accumulates in the spleen and bone marrow in a murine model of APL. We observed that these cells are capable of efficiently generating leukemia in recipient mice, demonstrating that this population represents the APL cancer-initiating cell. These cells down-regulate the transcription factor CCAAT/enhancer binding protein alpha (C/EBP alpha) possibly through a methylation-dependent mechanism, indicating that C/EBP alpha deregulation contributes to transformation of APL cancer-initiating cells. Our findings provide further understanding of the biology of APL by demonstrating that a committed transformed progenitor can initiate and propagate the disease. (Blood. 2009; 114: 5415-5425)
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Individual differences in drug efficacy or toxicity can be influenced by genetic factors. We investigated whether polymorphisms of pharmacogenes that interfere with metabolism of drugs used in conditioning regimen and graft-versus-host disease (GvHD) prophylaxis could be associated with outcomes after HLA-identical hematopoietic stem cell transplantation (HSCT). Pharmacogenes and their polymorphisms were studied in 107 donors and patients with leukemia receiving HSCT. Candidate genes were: P450 cytochrome family (CYP2B6), glutathione-S-transferase family (GST), multidrug-resistance gene, methylenetetrahydrofolate reductase (MTHFR) and vitamin D receptor (VDR). The end points studied were oral mucositis (OM), hemorrhagic cystitis (HC), toxicity and venoocclusive disease of the liver (VOD), GvHD, transplantation-related mortality (TRM) and survival. Multivariate analyses, using death as a competing event, were performed adjusting for clinical factors. Among other clinical and genetic factors, polymorphisms of CYP2B6 genes that interfere with cyclophosphamide metabolism were associated with OM (recipient CYP2B6*4; P=0.0067), HC (recipient CYP2B6*2; P=0.03) and VOD (donor CYP2B6*6; P=0.03). Recipient MTHFR polymorphisms (C677T) were associated with acute GvHD (P=0.03), and recipient VDR TaqI with TRM and overall survival (P=0.006 and P=0.04, respectively). Genetic factors that interfere with drug metabolisms are associated with treatment-related toxicities, GvHD and survival after HLA-identical HSCT in patients with leukemia and should be investigated prospectively.
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Survival of bone marrow transplant recipients requiting mechanical ventilation is poor but improving. This study reports a retrospective audit of all haematopoietic stem cell transplant (HSCT) recipients requiring mechanical ventilation at an Australian institution over a period spanning 11 years from 1988 to 1998. Recipients of autologous transplants are significantly less likely to require mechanical ventilation than recipients of allogeneic transplants. Of 50 patients requiring mechanical ventilation, 28% survived to discharge from the intensive care unit, 20% to 30 days post-ventilation, 18% to discharge from hospital and 12% to six months post-ventilation. Risk factors for mortality in the HSCT recipient requiting mechanical ventilation include renal, hepatic and cardiovascular insufficiency and greater severity of illness. Mechanical ventilation of HSCT recipients should not be regarded as futile therapy.
Resumo:
The purpose of this investigation was to assess changes in total energy expenditure (TEE), body weight (BW) and body composition following a peripheral blood stem cell transplant and following participation in a 3-month duration, moderate-intensity, mixed-type exercise programme. The doubly labelled and singly labelled water methods were used to measure TEE and total body water (TBW). Body weight and TBW were then used to calculate percentage body fat (%BF), and fat and fat-free mass (FFM). TEE and body composition measures were assessed pretransplant (PI), immediately post-transplant (PII) and 3 months post-PII (PIII). Following PII, 12 patients were divided equally into a control group (CG) or exercise intervention group (EG). While there was no change in TEE between pre- and post-transplant, BW (P