A comparison of traditional vs. Canadian tailored prophylaxis dosing of prophylactic factor infusions in children with haemophilia A and B in a single hemophilia treatment center.

Prophylactic infusion of clotting factor concentrates is a developing standard of care for individuals with haemophilia. The ideal schedule and techniques of prophylactic infusions remain incompletely defined. Our aim was to determine the optimal techniques and schedules for factor prophylaxis in paediatric patients. A retrospective electronic medical record review of all children treated with prophylactic factor infusions in a single Haemophilia Treatment Center was conducted. Comparison of traditional vs. Canadian dosing regimens and primary vs. secondary prophylaxis was made. Failure of prophylaxis was defined as the first serious bleed. A total of 58 children were identified for review. Five cases were excluded (four due to high titre inhibitors and one due to repeated non-compliance), thus there were 53 total cases: 46 with severe haemophilia, 2 with moderate haemophilia, 5 with mild haemophilia, 44 with haemophilia A and 9 with haemophilia B; 32 Traditional dosing and 21 Canadian dosing regimens. Patients on primary prophylaxis had a decreased failure rate (25%) compared to children treated with secondary prophylaxis (67%) regardless of technique of prophylaxis. When compared to a 'Traditional' factor prophylaxis schedule, the 'Canadian' tailored prophylaxis protocol was comparable with the exception of a decreased use of implanted venous devices in the 'Canadian' group. Ongoing bleeding (primarily joint bleeds) occurs with all prophylactic regimens. The lowest incidence of treatment failure was noted in children who began primary prophylaxis at a young age and before initial joint bleeds. Primary prophylaxis is superior to secondary prophylaxis regardless of dosing regimen. Traditional and Canadian dosing regimens were equivalent in outcome when measured over several years of follow-up.

Operative management and outcomes in children with congenital bleeding disorders: a retrospective review at a single haemophilia treatment centre.

Establishing haemostasis for surgical procedures in children with inherited bleeding disorders is challenging. Providers are often hesitant to undertake surgeries in children with bleeding disorders out of fear of bleeding complications. To review the preoperative management and haemorrhagic complications of children with inherited bleeding disorders at our institution, we conducted a retrospective electronic medical record review from 1999 to 2010. Primary focus was review of bleeding complications and factor replacement strategies. A total of 168 procedures were performed in 66 children. Fifteen procedures (8%) in four children were performed in the presence of high-titre factor inhibitors. Procedures included central venous catheter (CVL) placement or revision (41%), otolaryngology procedures (23%), dental (11%), non-synovectomy orthopaedic procedures (8%), synovectomy (5%), circumcision (5%) and miscellaneous (7%). All patients received preoperative factor replacement (100% in haemophilia patients) followed by various factor replacement regimens postoperatively. No deaths or life-threatening bleeding occurred with any procedure. Twelve of 168 procedures (7%) were complicated by bleeding. Tonsillectomy was the most common procedure complicated by haemorrhage 4 of 15 (26%) followed by nasal surgery (3/7 bleeds = 43%). The CVL surgeries were remarkably free of complications with only 1/69 (1.4%) with bleeding. Surgical procedures are safe in children with bleeding disorders with adequate planning and factor replacement. Bleeding remains a problem in a subset of patients and requires ongoing haematological involvement and oversight. Delayed bleeding following T&A was especially common and suggests a need for close follow-up and ongoing factor coverage for this group of patients.

Relationship of F-actin distribution to development of polar shape in human polymorphonuclear neutrophils.

Polymerization of actin has been associated with development of polar shape in human neutrophils (PMN). To examine the relation of filamentous actin (F-actin) distribution to shape change in PMN, we developed a method using computerized video image analysis and fluorescence microscopy to quantify distribution of F-actin in single cells. PMN were labeled with fluorescent probe NBD-phallicidin to measure filamentous actin and Texas red to assess cell thickness. We show that Texas red fluorescence is a reasonable measure of cell thickness and that correction of the NBD-phallicidin image for cell thickness using the Texas red image permits assessment of focal F-actin content. Parameters were derived that quantify total F-actin content, movement of F-actin away from the center of the cell, asymmetry of F-actin distribution, and change from round to polar shape. The sequence of change in F-actin distribution and its relation to development of polar shape in PMN was determined using these parameters. After stimulation with chemotactic peptide at 25 degrees C, F-actin polymerized first at the rim of the PMN. This was followed by development of asymmetry of F-actin distribution and change to polar shape. The dominant pseudopod developed first in the region of lower F-actin concentration followed later by polymerization of actin in the end of the developed pseudopod. Asymmetric F-actin distribution was detected in round PMN before development of polar shape. Based upon these data, asymmetric distribution of F-actin is coincident with and probably precedes development of polar shape in PMN stimulated in suspension by chemotactic peptide.

Climatic fluctuations due to deep ocean circulation.

A simple climate model that includes the effect of deep ocean turnover as a pure time delay exhibits an oscillatory behavior. The deep ocean signal contains frequencies characteristic of both the forcing function and the deep ocean delay.

Expression of dominant negative Erk2 inhibits AP-1 transactivation and neoplastic transformation.

The mitogen activated protein (MAP) kinases or extracellular signal-regulated kinases (Erks) are activated in response to Ras expression or exposure to tumor promoters or to growth factors, and have been implicated in AP-1 transactivation in some models. We have shown that tumor promoter induced activation of the transcription factor AP-1 is required for induced neoplastic transformation in the Balb/C JB6 cell model. Jun and Fos family protein levels have been found not to be limiting for AP-1 response. The present study asks whether activation of Erks1 and 2 is required for AP-1 transactivation and transformation of JB6 cells and whether Erks might be targeted for cancer prevention. Expression of either of two different dominant negative kinase inactive Erk2 mutants in transformation sensitive (P+) JB6 cells substantially inhibited the tumor promoter induced activation of Erks1 and 2 and of AP-1 measured by a collagenase-luciferase reporter. Multiple mutant Erk2 expressing clonal lines were also rendered non-responsive to induced neoplastic transformation. These observations, together with our recent finding attributing AP-1 non-responsiveness to Erk deficiency in a clonal line of transformation resistant (P-) cells, argue for a requirement for Erks1 and/or 2 activation in AP-1 transactivation in the mouse JB6 neoplastic progression model, and suggest the utility of Erks as a prevention target.

Accidental poisoning with a superwarfarin compound (brodifacoum) in a child.

The "superwarfarin" compounds are 4-hydroxy derivatives of coumarin that have increased activity and a longer duration of action than the parent compound. The superwarfarins are used widely in the United States as rodenticides and are effective against warfarin-resistant strains of rats. A chronic accidental ingestion of one of these products, brodifacoum, by a 7-year-old child who had bleeding and laboratory evidence suggestive of a vitamin K-related coagulopathy is reported. The bleeding manifestations were severe and prolonged, requiring 13 months for normalization of coagulation times. With a negative history of ingestion and despite clinical suspicion, documentation of superwarfarin poisoning was hampered by the lack of readily available assays for these compounds, even from the manufacturers. Brodifacoum was also identified in rat feces from the family home. This finding raises the concern of poisoning not only from ingestion of brodifacoum particles themselves, but also from a fecal-oral route. A review of the literature is presented and the implications of this case for the practicing physician are discussed.

Identification of BCR-ABL fusion on chromosome 9 by fluorescence in situ hybridization in two chronic myeloid leukemia cases.

We present two cases with hidden Philadelphia translocations that resulted from an insertion and a complex translocation. These cases were unusual in having the BCR/ABL fusion localized to chromosome 9q34. A review of cases with these uncommon presentations of BCR/ABL and prognostic presentation is presented.

Cerebrovascular effects and tumor kinetics after a single intratumoral injection of human recombinant interleukin-2 alone or in combination with intravenous chemotherapy in a rat model of glioma.

It is well documented that drug delivery into experimental and human brain tumors is limited by the variably intact blood-brain barrier (BBB) at the growing edge. The aim of the present investigation was to examine the histopathological changes that occur after a single intralesional injection of human recombinant interleukin-2 (rIL-2) into a growing glioma and determine whether the injection improved delivery of cytotoxic drug into the neuropil surrounding the site of lymphokine injection. Because an intracerebral injection of rIL-2 causes a temporary breakdown in the BBB, we hoped to enhance drug penetration into peritumoral areas of brain with an intact BBB by using the novel biomodulating effect of rIL-2 on the cerebral endothelial cells. The results demonstrated that an intralesional injection of 7.2 x 10(4) National Units rIL-2 on Day 7 after tumor inoculation did not accentuate the already increased cerebrovascular permeability produced by the glioma nor did rIL-2 trigger additional or aggravate neurological deficits in glioma-bearing rats. Before the administration of chemotherapy in vivo, the RT-2 glioma cells were tested for in vitro sensitivity by colorimetric assay. At 24 hours after exposure to either methotrexate (MTX), vincristine (VIN), or doxorubicin (DOX), no significant inhibition of metabolic activity was observed. In contrast, a timed pulsed of any drug for 5 minutes caused significant dose-dependent inhibition of RT-2 glioma cells at 48 hours to 5 days after drug administration. Animal models receiving an intralesional injection of rIL-2 followed 3 days later by an intravenous dose of 30 mg/kg MTX, 0.23 mg/kg VIN, or 10 mg/kg DOX demonstrated that only MTX combined with intralesional rIL-2 significantly inhibited intracranial proliferation of RT-2 glioma cells. Use of intralesional rIL-2 and intravenous chemotherapy, however, did not significantly increase survival in this animal model of glioma. These results show that the combination of cytotoxic drugs with intralesional rIL-2 can be safely applied in the management of glioma and may form a rational basis for additional pharmacological investigations of a wider assortment of chemotherapies in combination with rIL-2 for intracranial malignancies.

Histopathological and blood-brain barrier changes in rats induced by an intracerebral injection of human recombinant interleukin 2.

Adoptive immunotherapy utilizing human recombinant interleukin 2 (rIL-2) in conjunction with lymphokine-activated killer cells has shown some efficacy in the treatment of various types of cancers, particularly renal carcinoma and melanoma. Intravenous administration of rIL-2, with or without lymphokine-activated killer cells, produces a variety of serious side effects and approximately one-third of the patients experience a decrease in neurological status. Our previous investigations in animals have indicated that a single intravenous injection of rIL-2 can compromise the integrity of the blood-brain barrier (BBB). The present study examined the histopathological effect and BBB changes in rats which occur after a single intracerebral injection of rIL-2, its excipient, or saline into the parietal lobe. Animals were killed at various intervals up to 8 days (1 hour after intravenous injection of horseradish peroxidase), and the brain tissue was sectioned and processed for light microscopy. All animals showed increased cerebrovascular permeability for horseradish peroxidase due to traumatic BBB disruption at 4, 12, and 24 hours after injection. Extravasation of horseradish peroxidase persisted at 3 and 8 days only in animals injected with rIL-2. Injections of rIL-2 led to an increased leukocytic infiltration into the injection site, perivascular cuffing, and localized edema by 24 hours, which continued to increase over the 8-day study period. These results suggest that a single injection of human rIL-2 into the brain of rats induces an influx of leukocytes into the brain and may contribute to the cellular events that perpetuate a trauma-induced compromise in the integrity of the BBB.

A clinically applicable technique to study cytoskeletal dynamics in normal and abnormal polymorphonuclear leukocytes isolated from small volume blood samples.

Shape change and motility of polymorphonuclear leukocytes (PMNs) are essential for host defense and require dynamic reorganizations of microfilamentous cytoskeleton by reversible polymerization of G-actin into filaments (F-actin). Although clinical disorders of actin polymerization are rare, recently described simple methodologies for assaying actin dynamics in PMNs make the technique readily applicable to clinical studies. To develop a clinically useful F-actin assay, the authors investigated the optimal preparation conditions for PMN isolation that resulted in the least in vitro cytoskeletal activation and evaluated the variability in actin dynamics in acutely and chronically infected patients. Basal and chemotactic factor-activated PMN F-actin content was measured by a previously described flow cytometric technique in fixed, permeabilized, NBDphallacidin-stained PMNs isolated by centrifugation in Percoll or Ficoll-Hypaque density gradients or by countercurrent elutriation. F-actin content is expressed as mean fluorescent channel or relative fluorescence intensity. Basal F-actin in PMNs prepared from countercurrent elutriation (mean fluorescent channel = 79.0 +/- 4.5, n = 6) or by Ficoll Hypaque (82.0 +/- 3.5, n = 4) was significantly higher than endotoxin free, Percoll purified PMNs, whether purified in bulk (56.1 +/- 7.9, n = 8) or by the small volume modification applicable to clinical studies (53.3 +/- 8.7, n = 15). Basal Ficoll Hypaque purified PMNs have evidence of shape change, whereas endotoxin free, Percoll purified PMNs are smooth and round and represent the most basal cell equivalent in F-actin content to a circulating PMN.(ABSTRACT TRUNCATED AT 250 WORDS)

Alpha 1-antitrypsin deficiency in a child with X-linked lymphoproliferative disease.

An 18-month-old white male infant with X-linked lymphoproliferative disease was evaluated for persistent hepatic dysfunction following primary Epstein-Barr virus infection. A liver biopsy revealed cirrhosis with a dense mononuclear cell infiltrate. These findings were confounding because cirrhosis is not a typical finding in either normal or immunodeficient individuals following infection with Epstein-Barr virus. An alpha 1-antitrypsin level obtained shortly after biopsy was spuriously within the lower limits of the physiologic range. Further investigation demonstrated a homozygous Z phenotype, the classic protease inhibitor variant described in alpha 1-antitrypsin deficiency. A repeat liver biopsy confirmed the presence of a second hereditary disease. This is a unique concurrence of two uncommon genetic disorders.

Severe and fatal anthracycline cardiotoxicity at cumulative doses below 400 mg/m2: evidence for enhanced toxicity with multiagent chemotherapy.

Three cases of severe, progressive, and in two cases, fetal cardiomyopathy secondary to anthracycline chemotherapy are reported. All of the patients were receiving multiagent chemotherapy for extremity sarcomas consisting of doxorubicin, high-dose methotrexate, bleomycin, cyclophosphamide, dactinomycin, and cisplatinum at the onset of their congestive heart failure. Cardiomyopathy developed in each patient at cumulative anthracycline doses less than 400 mg/m2. These cases suggest that enhanced cardiotoxicity may occur when anthracyclines are used in combination with other agents such as cyclophosphamide, bleomycin, cisplatinum, and methotrexate and that cumulative anthracycline doses considered to be "safe" may need to be lowered in these circumstances.

Dephosphorylation of a 34kd triton-insoluble F-actin pool protein is associated with phorbol ester-induced actin polymerization in human polymorphonuclear leukocytes.

Activation of human polymorphonuclear leukocytes (PMNs) by chemotactic peptide (FMLP) or phorbol ester (PMA) results in actin reorganization and PMN motility. Evidence suggests that PMA and FMLP activate PMN actin reorganization by different mechanisms. For example, the protein phosphatase inhibitor, okadaic acid (OA), inhibits PMA- but not FMLP-induced actin rearrangement, suggesting protein dephosphorylation is key to PMA but not FMLP actin changes and that PMN actin reorganization occurs by multiple mechanisms. Further support for multiple actin polymerization mechanisms is the recent description of distinct F-actin pools coexisting with G-actin in PMNs, Triton insoluble F-actin (TIF) and Triton soluble F-actin (TSF). These studies examine quantitative actin pool-specific actin polymerization in PMA- and FMLP-activated PMNs using quantitative SDS-PAGE and the phosphorylation of proteins in each actin pool using 32P orthophosphate (32P) labeling. The results show: (1) OA alone has no effect on actin pool content; (2) PMA induces actin growth only in the TIF pool similar to results with FMLP, and (3) OA pretreatment has no effect on FMLP actin polymerization, but inhibits PMA-induced changes. 32P results show that in basal PMNs, multiple phosphoproteins are found in the TIF including a protein of MW 34kd (pp34), the TSF pool contains a pp34 and a pp69 and the G-actin pool a pp34. PMA induces dephosphorylation of pp34 in the TIF (0.59 +/- 0.14 x basal, n = 3). OA prior to PMA prevents TIF pp34 dephosphorylation and actin shifts between the TIF, TSF, and G pools. OA alone results in phosphorylation of pp34 in all actin pools but no shift in actin content. The results show that (1) phosphoproteins exist in all three actin pools of PMNs-TIF-actin, TSF-actin, and G-actin; (2) both PMA and FMLP cause quantitatively identical actin polymerization in the TIF; and (3) in contrast, PMA but not FMLP TIF growth requires dephosphorylation of a pp34. This as yet unidentified phosphoprotein appears crucial to PMA- but not FMLP-induced actin polymerization.

Adherence of human phagocytes results in characteristic reorganization and redistribution of distinct F-actin pools.

The F-actin based microfilamentous cytoskeleton (MFC) provides mobility for phagocytic immune cells including polymorphonuclear leukocytes (PMNs) and macrophages (MOs). In PMNs in suspension, the MFC is organized into two distinct F-actin pools [Triton Insoluble F-actin-(TIF), which form the sub-membranous, 3D actin meshwork and Triton Soluble F-actin (TSF), which exists as short oligomers] in equilibrium with G-actin. The structure of F-actin pools in adherent cells is unknown despite the fact that phagocytes are adherent in tissues in vivo. In order to determine the structure of F-actin pools in adherent phagocytes, human PMNs were isolated and allowed to adhere to plastic for 1 hour at 37 degrees C. Adherent cells were collected, actin pools separated and quantified by SDS-PAGE and compared to nonadherent PMNs in suspension. Likewise, the nonadherent human myeloid cell line U937 was induced to MO morphology and adherence by exposure to TPA (10(-6) M x 3 days) and similarly evaluated. Adherence of PMNs to plastic resulted in 75 +/- 15% adherence (n = 3). TPA differentiation of U937 cells resulted in 81 +/- 15% adherence (n = 10). In both cells, adherence resulted in a statistically significant increase in TIF, a decrease in TSF, and little to no change in G-actin. Basal, nonadherent PMNs in suspension contain TIF 40 +/- 0%, TSF 20 +/- 4%, and G-actin 40 +/- 4%, n = 3, whereas adherent PMNs contain TIF 61 +/- 3%, TSF 5 +/- 5%, G-actin 34 +/- 1%, n = 3. Basal U937 contain TIF 41 +/- 9%, TSF 17 +/- 6%, and G-actin 42 +/- 13%, n = 7. Adherent MO-like U937 contain TIF 53 +/- 4%, TSF 9 +/- 5%, and G-actin 38 +/- 4%. The results show that phagocyte adherence leads to a characteristic reorganization of actin pool structure that is remarkably quantitatively similar to, yet mechanistically distinct from, reorganization by chemotactic factor activation in suspension. Adherence-induced TIF-actin growth results exclusively from conversion of TSF-actin to TIF-actin.

Role of gelsolin in the formation and organization of triton-soluble F-actin during myeloid differentiation of HL-60 cells.

Structurally and functionally distinct F-actin pools coexist with globular (G)-actin in a variety of eukaryotic cells, including polymorphonuclear leukocytes (PMNs). In PMNs, a Triton-soluble F-actin pool (TSF) exists as short cytoplasmic filaments capped with gelsolin, while Triton-insoluble F-actin (TIF) is a three-dimensional meshwork of F-actin associated with actin-binding protein 280 (ABP-280), alpha-actinin, and tropomyosin. The unique association of gelsolin with the TSF suggests a role for gelsolin in creation or regulation of TSF. To evaluate gelsolin's role in TSF formation, the quantities of actin and gelsolin were determined by quantitative sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblots in uninduced HL-60 cells (U-HL-60) and in HL-60 cells induced to myeloid differentiation with 1.25% dimethyl sulfoxide for 4 to 5 days (I-HL-60). U-HL-60 cells contain 17.76 +/- 6.01 pmol actin per 10(6) cells (TIF, 5.3 +/- 1.5; TSF, 2.17 +/- 0.37; G, 10.3 +/- 5.7; n = 5) and 0.073 pmol gelsolin per 10(6) cells (TIF, 0; TSF, 0.002 +/- 0.005; G, 0.07 +/- 0.01; n = 3), representing molar actin to gelsolin (A:G) ratios of 1,085:1 for TSF and 147:1 for G. After myeloid differentiation, the actin content increases 1.80-fold (31.94 +/- 6.14 pmol/10(6) cells) equally in each actin pool (TIF, 9.36 +/- 2.35; TSF, 3.29 +/- 0.62; G, 19.29 +/- 4.83). Gelsolin increases 2.4-fold overall (0.178 +/- 0.02 pmol/10(6) cells) but 19-fold in TSF (0.038 +/- 0.009) and only 1.9-fold in G pool (0.139 +/- 0.006), resulting in A:G ratios of 87:1 in TSF and 139:1 in G. The findings of an increase in TSF gelsolin with decreased A:G ratios (1,085:1 v 87:1) with myeloid differentiation suggest shortening of TSF filaments, while the A:G ratios of unbound gelsolin are unchanged (147:1 v 139:1). Measurement of EGTA-resistant gelsolin/actin complexes in HL-60 cells shows that 95% to 100% of complexes exist in the TSF-actin pool only. These findings are consistent with a role for gelsolin in formation and organization of Triton-soluble F-actin. Furthermore, the apparent shortening of TSF-actin filaments with myeloid cellular differentiation and maturation may represent one mechanism of conversion of the nonmotile myeloblast to the motile PMN.

Combination chemotherapy with ifosfamide and etoposide is effective in the treatment of central nervous system metastasis of childhood neuroblastoma.

Childhood neuroblastoma is a neural crest-derived tumor that presents most commonly during this period of life. In disseminated form, it is resistant to cure by chemotherapy. The tumor tends to recur in diverse locations after an initial clinical response. The parenchyma of the central nervous system (CNS) is a rare location for metastatic disease and typically represents terminal disease spread. Therefore, effective therapy for CNS metastasis of neuroblastoma has not been reported. The authors describe the case of a child who had a large parenchymal CNS metastasis at the time of initial recurrence of Stage IV neuroblastoma. Chemotherapy with ifosfamide and etoposide resulted in complete resolution of this lesion.

Evidence for a gelsolin-rich, labile F-actin pool in human polymorphonuclear leukocytes.

Filamentous (F) actin is a major cytoskeletal element in polymorphonuclear leukocytes (PMNs) and other non-muscle cells. Exposure of PMNs to agonists causes polymerization of monomeric (G) actin to F-actin and activates motile responses. In vitro, all purified F-actin is identical. However, in vivo, the presence of multiple, diverse actin regulatory and binding proteins suggests that all F-actin within cells may not be identical. Typically, F-actin in cells is measured by either NBDphallacidin binding or as cytoskeletal associated actin in Triton-extracted cells. To determine whether the two measures of F-actin in PMNs, NBDphallacidin binding and cytoskeletal associated actin, are equivalent, a qualitative and quantitative comparison of the F-actin in basal, non-adherent endotoxin-free PMNs measured by both techniques was performed. F-actin as NBDphallacidin binding and cytoskeletal associated actin was measured in cells fixed with formaldehyde prior to cell lysis and fluorescent staining (PreFix), or in cells lysed with Triton prior to fixation (PostFix). By both techniques, F-actin in PreFix cells is higher than in PostFix cells (54.25 +/- 3.77 vs. 23.5 +/- 3.7 measured as mean fluorescent channel by NBDphallacidin binding and 70.3 +/- 3.5% vs. 47.2 +/- 3.6% of total cellular actin measured as cytoskeletal associated actin). These results show that in PMNs, Triton exposure releases a labile F-actin pool from basal cells while a stable F-actin pool is resistant to Triton exposure. Further characterizations of the distinct labile and stable F-actin pools utilizing NBDphallacidin binding, ultracentrifugation, and electron microscopy demonstrate the actin released with the labile pool is lost as filament. The subcellular localization of F-actin in the two pools is documented by fluorescent microscopy, while the distribution of the actin regulatory protein gelsolin is characterized by immunoblots with anti-gelsolin. Our studies show that at least two distinct F-actin pools coexist in endotoxin-free, basal PMNs in suspension: 1) a stable F-actin pool which is a minority of total cellular F-actin, Triton insoluble, resistant to depolymerization at 4 degrees C, gelsolin-poor, and localized to submembranous areas of the cell; and 2) a labile F-actin pool which is the majority of total cellular F-actin, Triton soluble, depolymerizes at 4 degrees C, is gelsolin-rich, and distributed diffusely throughout the cell. The results suggest that the two pools may subserve unique cytoskeletal functions within PMNs, and should be carefully considered in efforts to elucidate the mechanisms which regulate actin polymerization and depolymerization in non-muscle cells.

Isolation and characterization of transforming growth factor beta response variants from human prostatic tumor cell lines.

In this study we examined the relation between the response to transforming growth factor beta (TGF beta 1) in vitro and the growth in vivo of 1-LN-PC3-1A (1-LN) human prostatic carcinoma cells. 1-LN cells resistant to the growth-inhibitory effects of TGF beta 1 were isolated after exposure to 2 ng/ml TGF beta 1 in an anchorage-independent growth assay. Cloning of TGF beta 1-resistant and -sensitive populations produced 2 clones (R2-6 and 1-LN clone 4), which maintained relatively stable resistance or sensitivity, respectively, in the absence of TGF beta 1 for up to 12 passages. Colony formation by the R2-6 cells in the presence of TGF beta 1 was 2-10 times greater than that of 1-LN clone 4, depending upon the TGF beta 1 concentration. Injection of 1 x 10(5) R2-6 cells into athymic nude mice produced tumors with a significantly shorter latency interval as compared with 1-LN clone 4 tumors (P < 0.0001). Western immunoblotting showed that higher levels of latent TGF beta 1 protein were secreted into the culture medium by 1-LN clone 4 cells. Acidified conditioned media from both clones inhibited mink lung epithelial cell DNA synthesis. Neutralizing monoclonal antibody to TGF beta 1 but not TGF beta 2 abrogated this inhibitory effect. Comparison of the different sensitive and resistant clones showed that in vitro sensitivity to TGF beta 1 and in vivo tumor latency interval were not invariably correlated. Thus, the TGF beta 1 response phenotype in vitro was not always predictive of growth delay in vivo.

Pulmonary interstitial disease mimicking idiopathic pneumonia syndrome as the initial site of relapse of neuroblastoma following autologous bone-marrow transplantation: a case report.

Pulmonary interstitial infiltrates are a common diagnostic dilemma following bone-marrow transplantation. We present a case report of a child presenting with recurrent, metastatic neuroblastoma after bone-marrow transplantation, manifested initially as pulmonary interstitial disease mimicking idiopathic pneumonia syndrome.