Tyrosine kinases expressed in vivo by human prostate cancer bone marrow metastases and loss of the type 1 insulin-like growth factor receptor.
(9/285)
An important biological feature of prostate cancer (PCa) is its marked preference for bone marrow as a metastatic site. To identify factors that may support the growth of PCa in bone marrow, expression of receptor and nonreceptor tyrosine kinases by androgen-independent PCa bone marrow metastases was assessed. Bone marrow biopsies largely replaced by PCa were analyzed using reverse transcriptase-polymerase chain reaction amplification with degenerate primers that amplified the conserved kinase domain. Sequence analyses of the cloned products demonstrated expression of multiple kinases. Expression of the receptor and nonreceptor tyrosine kinases, alpha platelet-derived growth factor receptor and Jak 1, respectively, was confirmed by immunohistochemistry. In contrast, the type 1 insulin-like growth factor receptor, thought to play a role in PCa development, was lost in metastatic PCa. These results implicate several specific growth factors and signaling pathways in metastatic androgen-independent PCa and indicate that loss of the type 1 insulin-like growth factor receptor contributes to PCa progression. (+info)
Micrometastases of bone marrow in localized prostate cancer: correlation with established risk factors.
(10/285)
PURPOSE: The presence of cytokeratin 18-positive cells in bone marrow correlates with conventional risk factors in many tumors. We examined whether this was also valid for localized or lymphatically spread prostate cancer. PATIENTS AND METHODS: Immediately before radical prostatectomy, bone marrow aspirates from both sides of the iliac crest were taken from 287 patients. The presence of cells containing cytokeratin 18 was interpreted as micrometastasis. RESULTS: In patients with negative lymph nodes (n = 219), conventional risk factors (Gleason score, pathologic stage, ploidy, and preoperative prostate-specific antigen) did not correlate with the preoperative detection of cells containing cytokeratin 18. There was also no correlation with lymph node metastases. Furthermore, there was no interdependency between the preoperatively detected number of cells and the established risk factors. CONCLUSION: We assume the presence of epithelial cells in bone marrow to be an independent parameter, the clinical importance of which must be substantiated by further studies. (+info)
Phase II window of idarubicin in children with extraocular retinoblastoma.
(11/285)
PURPOSE: The aim of this study was to evaluate in an upfront phase II study the response to idarubicin in children with extraocular retinoblastoma. PATIENTS AND METHODS: The starting dose of idarubicin was 15 mg/m(2)/d (days 1 and 2) weeks 0 and 3. After an interim evaluation, the dose was reduced to 10 mg/m(2)/d (days 1 and 2) weeks 0 and 3 because of hematopoietic toxicity. Response was evaluated at week 6. RESULTS: At the Hospital JP Garrahan (Buenos Aires, Argentina), 10 patients (five bilateral) were entered onto the study from 1995 to 1998. A total of 19 cycles were administered. Extraocular sites included orbit (n = 10), bone marrow (n = 3), bone (n = 1), lymph node (n = 1), and CNS (n = 1). The response rate was 60% (95% confidence interval, 30% to 90%). One complete response was achieved, in addition to five partial responses, two cases of stable disease, and two cases of progressive disease. All patients with bone marrow involvement achieved complete clearance of tumor cells. The patient with CNS disease had progressive disease. All patients had severe hematopoietic toxicity (grade 4 neutropenia and grade 3/4 thrombocytopenia after most cycles). Other toxicities included grade 2 diarrhea in 30%. No echocardiographic changes were detected. CONCLUSION: Idarubicin is active in extraocular retinoblastoma. The activity of this drug should be explored in future phase III studies. (+info)
Increased expression of preprotachykinin-I and neurokinin receptors in human breast cancer cells: implications for bone marrow metastasis.
(12/285)
Neuropeptides are implicated in many tumors, breast cancer (BC) included. Preprotachykinin-I (PPT-I) encodes multiple neuropeptides with pleiotropic functions such as neurotransmission, immune/hematopoietic modulation, angiogenesis, and mitogenesis. PPT-I is constitutively expressed in some tumors. In this study, we investigated a role for PPT-I and its receptors, neurokinin-1 (NK-1) and NK-2, in BC by using quantitative reverse transcription-PCR, ELISA, and in situ hybridization. Compared with normal mammary epithelial cells (n = 2) and benign breast biopsies (n = 21), BC cell lines (n = 7) and malignant breast biopsies (n = 25) showed increased expression of PPT-I and NK-1. NK-2 levels were high in normal and malignant cells. Specific NK-1 and NK-2 antagonists inhibited BC cell proliferation, suggesting autocrine and/or intercrine stimulation of BC cells by PPT-I peptides. NK-2 showed no effect on the proliferation of normal cells but mediated the proliferation of BC cells. Cytosolic extracts from malignant BC cells enhanced PPT-I translation whereas extracts from normal mammary epithelial cells caused no change. These enhancing effects may be protein-specific because a similar increase was observed for IL-6 translation and no effect was observed for IL-1alpha and stem cell factor. The data suggest that PPT-I peptides and their receptors may be important in BC development. Considering that PPT-I peptides are hematopoietic modulators, these results could be extended to understand early integration of BC cells in the bone marrow, a preferred site of metastasis. Molecular signaling transduced by PPT-I peptides and the mechanism that enhances translation of PPT-I mRNA could lead to innovative strategies for BC treatments and metastasis. (+info)
Monoclonal antibody therapy with edrecolomab in breast cancer patients: monitoring of elimination of disseminated cytokeratin-positive tumor cells in bone marrow.
(13/285)
Despite current advances in antibody-based immunotherapy of breast and colorectal cancer, we have recently shown that the actual target cells (e.g., tumor cells disseminated to bone marrow) may express a heterogeneous pattern of the potential target antigens. Tumor antigen heterogeneity may therefore represent an important limitation of the efficacy of monospecific antibody therapy. To measure the efficacy of such a monospecific approach, we analyzed the elimination of tumor cells coexpressing the epithelial cell adhesion molecule (EpCAM) under therapy with murine monoclonal antibody 17-1A (Edrecolomab) directed against EpCAM. In bone marrow aspirates from 10 breast cancer patients with metastatic (n = 8) and locoregional recurrence (n = 2), tumor cells were identified with the antibody A45-B/B3 directed against the epithelial differentiation marker cytokeratin (CK) and simultaneously typed for EpCAM expression using the antibody 17-1A. Patients were treated with a single dose of 500 mg of Edrecolomab and monitored by bone marrow analyses before and at days 5-7 after antibody treatment. In all 10 patients, we assessed a marked reduction in the mean numbers of both CK+ cells (73 versus 15; P = 0.003, t test) and EpCAM+/CK+ cells (17 versus 1; P = 0.003, t test) per 10(6) bone marrow cells. Complete elimination of EpCAM+ cells was possible in four patients. We conclude that Edrecolomab can be used in breast cancer patients to target isolated EpCAM+/CK+ cancer cells. Using CK-based immunoassays, we reliably detected residual tumor cells in bone marrow and typed EpCAM expression. This allowed us to monitor the cytotoxic elimination of such cells after Edrecolomab application. Selection of EpCAM-/ CK+ tumor clones showed that further antibodies directed against tumor-associated antigens are warranted to improve the efficacy of monospecific approaches. (+info)
Favorable biology and outcome of stage IV-S neuroblastoma with supportive care or minimal therapy: a Children's Cancer Group study.
(14/285)
PURPOSE: Stage IV-S neuroblastoma is a metastatic disease associated with spontaneous regression and good survival, but 10% to 20% of infants die from early complications. The purpose of this study was to evaluate outcome and prognostic factors in infants with stage IV-S neuroblastoma treated prospectively with supportive care only or, in symptomatic patients, with low-dose cytotoxic therapy. PATIENTS AND METHODS: Eighty eligible infants were studied for response and survival with supportive care or, for symptomatic patients, cyclophosphamide 5 mg/kg/d for 5 days with or without hepatic radiation of 4.5 Gy over 3 days. Staging was reviewed centrally, and MYCN gene copy number, Shimada histopathologic classification, serum ferritin levels, and bone marrow immunocytology were determined. RESULTS: Stage IV-S and International Neuroblastoma Staging System stage 4S were 98% concordant. MYCN was not amplified in any of the tumors tested (n = 58), and Shimada histopathologic classification was favorable in 96% (n = 68/71). The 5-year event-free survival (EFS) rate for all infants was 86% and the survival rate was 92%. Supportive care was the only treatment provided for 44 (55%) of 80 infants, and their 5-year survival rate was 100%, compared with 81% survival for those requiring cytotoxic therapy for symptoms (P =.005). Five of six deaths were in infants younger than 2 months of age at diagnosis and were due to complications of extensive abdominal involvement with respiratory compromise or disseminated intravascular coagulation. Although age +info)
Subchondral metastasis: report of five cases.
(15/285)
Subchondral metastasis is a rare occurrence and poses a diagnostic dilemma as initial films may show a lytic lesion in the subchondral region often misinterpreted as being benign. We present five cases of subchondral metastasis as well as a review of the literature. In our cases, we present subchondral metastasis in the elbow, shoulder, and hip joints. All patients had pain over the affected joint and most presented with a lytic lesion in the subchondral bone. Three patients have died since presentation and two are doing well at last follow up visit. Subchondral metastasis is a rare entity, but it should be included in the differential of a lytic lesion in the subchondral bone. (+info)
Plasma antioxidant status after high-dose chemotherapy: a randomized trial of parenteral nutrition in bone marrow transplantation patients.
(16/285)
BACKGROUND: Chemotherapy and radiation therapy result in increased free radical formation and depletion of tissue antioxidants. It is not known whether parenteral nutrition (PN) administered during bone marrow transplantation (BMT) supports systemic antioxidant status. OBJECTIVE: The aims of the study were to determine 1) whether high-dose chemotherapy decreases concentrations of major circulating antioxidants in patients undergoing BMT and 2) whether administration of standard PN maintains systemic antioxidant concentrations compared with PN containing micronutrients and minimal lipids alone. DESIGN: Twenty-four BMT patients were randomly assigned to receive either standard PN containing conventional amounts of dextrose, amino acids, micronutrients, and lipid (120 kJ/d) or a solution containing only micronutrients (identical to those in standard PN) and a small amount of lipid (12 kJ/d). Plasma antioxidant status was measured before conditioning therapy and serially at days 1, 3, 7, 10, and 14 after BMT. RESULTS: Plasma glutathione (GSH) and alpha- and gamma-tocopherol concentrations decreased and the GSH redox state became more oxidized after conditioning chemotherapy. Plasma cysteine concentrations were unchanged, whereas cystine concentrations increased. Plasma vitamin C and zinc concentrations and GSH peroxidase activity increased over time. Plasma alpha-tocopherol concentrations were lower in patients given standard PN. There were no differences in other plasma antioxidants between groups. CONCLUSIONS: A significant decline in GSH-glutathione disulfide, cysteine-cystine, and vitamin E status occurs after chemotherapy and BMT. Standard PN does not improve antioxidant status compared with administration of micronutrients alone. Further evaluation of PN formulations to support patients undergoing high-dose chemotherapy and BMT are needed. (+info)