Ganglioside gd(2) expression in the human nervous-system and in neuroblastomas - an immunohistochemical study

The distribution of the disialoganglioside GD2 in the human nervous system was studied by immunostaining using monoclonal antibodies 3F8 and 3A7. Positive staining was detected throughout the central nervous system, predominantly in neuronal cell bodies and neuropil of the gray matter. The specific localization of reactivity in such structures as cerebellum and hippocampus differs from that of related gangliosides, suggesting that GD2 may have a distinct functional role(s) in the brain, and is not merely a metabolic intermediate. GD2 expression was also analyzed in a series of 39 neuroblastomas. Staining of both primitive neuroblastic and differentiating ganglioneuromatous elements was seen, although some tumor cell heterogeneity was noted. The results have implications for immunotherapy of neuro-blastomas using anti-GD2 antibodies.

Retinopathy predicts coronary heart disease mortality

BACKGROUND

Retinopathy lesions are fairly common findings in clinic settings and may predict risk of coronary heart disease (CHD).

OBJECTIVE

To examine whether retinopathy independently predicts a risk of CHD-related mortality in people with and without diabetes.

METHODS

In an Australian population-based cohort of people with (n = 199) and without (n = 2768) diabetes (Blue Mountains Eye Study, total n = 2967), the presence and severity of retinopathy was assessed from retinal photographs. 12-Year cumulative CHD deaths were ascertained from Australian National Death Index records.

RESULTS

Over 12 years, 353 participants (11.9%) had incident CHD-related deaths. Retinopathy was present in 57/199 (28.6%) participants with, and in 268/2768 (9.7%) without, diabetes. The presence of retinopathy increased the CHD mortality rate per person-year by an amount (0.005) equivalent to the presence of diabetes itself (12-year CHD mortality rate per person-year of 0.010 in people with neither diabetes nor retinopathy, 0.015 in those with diabetes alone, 0.016 in those with retinopathy alone). After adjusting for cardiovascular risk factors, retinopathy remained an independent predictor of CHD death both in people with diabetes (hazard ratio (HR) = 2.21, 95% CI 1.20 to 4.05) and in those without diabetes (HR = 1.33, 95% CI 1.02 to 1.83). Moderate retinopathy was associated with adjusted HR = 6.68 (95% CI 2.24 to 20.0) in people with diabetes and adjusted HR = 2.29 (95% CI 1.10 to 4.76) in people without diabetes.

CONCLUSIONS

A finding of retinopathy in people with or without diabetes may signal increased CHD risk. The increased CHD mortality associated with retinopathy in people without diabetes was equivalent to the presence of diabetes itself.

Improving general practitioners' interviewing skills in managing patients with depression and anxiety: a randomized controlled clinical trial

BACKGROUND

Studies regarding the effectiveness of CME programmes on physicians' behaviour and communication skills showed inconsistent results. Few randomized controlled trials have been conducted in Asia.

METHODS

To evaluate the effectiveness of a 4 2-hour education programme to improve GP interviewing behaviours, 16 general practitioners were randomized to the intervention and control groups, respectively. Physicians assigned to the intervention group received 8 hours of training emphasizing interviewing behaviours in the diagnosis and treatment of depression and generalized anxiety disorders (GDS). Those assigned to the control group did not receive any training until the completion of study. Standardized patients were used to evaluate the performance of physicians. Two consultations before and after enrolling in the education programme were videotaped. Independent evaluations of consultations were made by a trained clinical psychologist and a social worker blinded to the study status of physicians. The rating schedule for the videotapes was based on the tasks listed on the Calgary Cambridge Observation Guide.

RESULTS

The change of score between the intervention and control physicians was significantly different in 'active listening and facilitating patients' response' (p = 0.011) with the intervention physicians having improvement of score. For 'non-verbals', 'understanding patient's perspective' and 'negotiating mutual plan of action', positive change of score in the intervention physicians were seen when compared to that of the control, although the difference did not reach statistical significance (p = 0.06, p = 0.05, p = 0.06, respectively). However, for 'opening', 'structuring the consultation', 'explanation and planning' and 'closure', there were no statistical significant differences between control and intervention group.

CONCLUSIONS

Our results showed that only certain communication skills, such as active listening and facilitating patient's response, can be taught in the management of depression and generalized anxiety disorder (GAD) in Chinese primary care physicians.

Specific gene expression profiles and unique chromosomal abnormalities are associated with regressing tumors among infants with disseminated neuroblastoma

9501

Background: Among human cancers, neuroblastoma (NB) has the highest incidence of spontaneous remission, especially among the subgroup of stage 4s NB affecting infants. Clinical distinction of stage 4s from lethal stage 4 can be difficult, but critical, since it is the basis for therapeutic decisions. The identification of biological markers that allow a precise distinction of these NB subgroups will aid accurate classification. Methods: Thirty-seven infants with NB were treated at MSKCC from 1987 to 2000. Ten stage 4s and 19 stage 4 were evaluated by allelic and gene expression analyses. Results: All stage 4s patients underwent spontaneous remission while only 69% of newly diagnosed, previously untreated stage 4 patients survived despite combined modality therapy. Among stage 4 tumors, 19/19 were near-diploid/tetraploid, 8/19 MYCN amplified, 50% had LOH at 1p36, 43% had LOH at 1p34-p31 and/or 14q and 37% had LOH at 11q and/or 1p22. Among stage 4s tumors, 7/8 were near-triploid, none MYCN-amplified and LOH was restricted to 11q. Gene expression profiling identified 233 differentially expressed genes between stage 4 and 4s tumors. 25% of these genes with increased expression in stage 4s NB mapped to 1pter-p13, with transcription level correlated with LOH and ploidy. Conclusions: These findings suggest that differential expression of subsets of genes located at specific chromosomal regions play a significant role in the biology of disseminated NB. Besides offering a biological definition of stage 4s, these expression profiles may provide new insights in the genetic control of spontaneous remission in neuroblastoma.

No significant financial relationships to disclose.

Metastatic neuroblastoma (NB) to the central nervous system (CNS): Improved outcome with combined modality including 131-I-8H9 or 131-I-3F8 radioimmunotherapy (RIT) delivered through the cerebrospinal fluid (CSF)

2022

Background: NB metastatic to the CNS (NB-CNS) is difficult to control. We describe a salvage regimen incorporating intra- Ommaya RIT delivered to the CSF. Methods: 37 patients (pts) with NB-CNS (parenchymal masses and/or leptomeningeal [LM] carcinomatosis) treated at MSKCC from 1988 through 2006 were reviewed. Nine (group #1) of 37 pts developed NB-CNS metastasis (median age 3.8 years) and were treated with a salvage regimen: resection of parenchymal masses, 2160 cGy craniospinal irradiation (CSI), intravenous irinotecan and oral temozolomide, and RIT with 131I-8H9 and or 131I-3F8 targeting tumor associated antigens on phase I/II studies. Immunotherapy (intravenous anti-GD2 monoclonal antibody 3F8 plus subcutaneous GM-CSF) was also given for systemic control. Survival was compared to the other 28 (group #2) pts who developed NB-CNS (median age 4.2 years) treated with combinations of surgery, chemotherapy, and radiation but without CSI + RIT. Results: All 37 pts had high risk disease at initial diagnosis of NB. 9 of 9 group #1 pts had marrow and/or bony involvement; 6 of 9 had MYCN amplification and 5 of 9 had serum LDH >1500 U/ml. All had intensive chemotherapy and radiotherapy prior to CNS relapse. Despite this, the CNS salvage regimen was well-tolerated. Myelosuppression following CSI and chemotherapy was common; 2 pts received stem cell support. All 9 pts in the RIT group are alive and well, disease-free at 3+, 11+, 15+, 18+, 18+, 20+, 22+, 31+, 42+ months since CNS relapse. In contrast, pts in group #2 had a median time to death of 5.5 months, (p<0.0001) for survival by Kaplan-Meier analysis. Conclusion: Similar to CNS metastases in most other solid tumors, conventional therapies have been ineffective for NB-CNS. The addition of RIT using 131I-3F8 or 131I-8H9 is well-tolerated and improves the prognosis for these high risk patients.

No significant financial relationships to disclose.

Phase I study of the combination of anti-GD2 antibody 3F8 and barley-derived (1→3,1→4)-β-D-glucan for patients with resistant neuroblastoma

9566

Background: Beta glucans are complex, naturally occurring polysaccharides that prime leucocyte dectin and CR3 receptors. Based on our preclinical observations that oral barley-derived (1→3,1→4)-β-D-Glucan (BG) synergizes with the murine anti-GD2 antibody 3F8 against neuroblastoma (NB) (Clin Cancer Res 8:1217), we conducted a phase I study to determine the safety of the combination of BG and 3F8 in patients with resistant NB. Methods: Heavily pre-treated patients with recurrent or refractory advanced stage NB were treated with 3F8/BG. Each cycle consisted of intravenous (IV) 3F8 at a fixed dose of 10 mg/m2/day ×10 days, plus oral BG dose escalated from 10 to 80 mg/kg/day ×10 days in 4 cohorts of 6 patients each. Patients without human anti-mouse antibody (HAMA) could be re-treated up to a total of 4 cycles. Results: Twenty-three patients with stage 4 and one with stage 3 NB (M:F = 11:13; median age 8 (range 2–19) years completed 47 cycles of therapy with 3F8/BG. 8 patients had progressive disease (PD) while 16 had stable refractory NB (SD) at enrollment. All patients completed at least one cycle of therapy and were evaluated for toxicity and response. Maximum tolerated dose for BG was not reached. Two patients developed dose-limiting toxicities (DLT). Both had grade 4 thrombocytopenia after completing one cycle of treatment: one at BG dose of 20mg/kg/day and the other at 40 mg/kg/day. Both cases responded to therapy with a short course of ITP (idiopathic thrombocytopenic purpura) therapy; one subsequently developed chronic ITP. There were no other >grade 2 toxicities related to 3F8/BG therapy. 14, 4, 2 and 6 patients completed 1, 2, 3 and 4 cycles respectively. Reasons for withdrawal in patients who did not complete 4 cycles were PD in 10, persistently elevated HAMA in 6 and DLT in 2. Overall 11 patients had SD and 13 PD. 14/23 patients with positive MIBG scans prior to therapy demonstrated improvement after one cycle. Responses did not correlate with BG dose received. 7 patients, all with residual disease survive at a median of 40 (range 24–45) months post-treatment. Conclusions: 3F8/BG is well tolerated and shows activity against resistant NB. Further clinical investigation of this novel combination is warranted.

No significant financial relationships to disclose.

STEAP1: A potential marker of metastatic disease for Ewing family tumors

10028

Background: Ewing Family Tumors (EFTs) metastasize by hematogeneous spread. Because of its dismal cure rate, targeting subclinical disease is particularly relevant. Genome-wide gene expression array analysis can uncover novel genes differentially expressed in tumors over normal marrow/blood, which may have clinical potentials as markers of minimal residual disease (MRD). Methods: Gene expression array data were obtained on 28 EFT tumors and 10 EFT cell lines using the Affymetrix U133 gene chip. Ten genes with high tumor to blood ratios were identified. Quantitative RT-PCR was performed to study (1) the dynamic range of detection of rare tumor cells (frequency of 10-7 to 10-4), (2) the gene expression in normal blood and marrow samples, (3) the gene expression among EFT tumors, and (4) the prognostic impact of marker positivity in EFT patients with histologically negative marrows. Results: Of the 10 genes, 5 genes, namely six transmembrane epithelial antigen of the prostate 1 [STEAP1], cyclin D1 [CCND1], plakophilin 1 [PKP1], transmembrane protein 47 [TMEM47], and NKX2.2 transcription factor [NKX2.2] were chosen for further analyses. This was based on their steep linear dynamic range in tumor cells seeded in normal mononuclear cells and consistently high expression among EFT tumor samples. Among 53 EFT patients with histologically negative marrow samples, a marker was classified as positive if the gene transcript level was above the upper limit of normal, defined as mean + 2SD of 26 normal blood and marrow samples. Of the 5 markers tested, STEAP1 positivity in marrow samples was highly correlated with survival with new metastasis in Kaplan Meier analysis (p=0.001). Conclusions: This gene expression array-based approach identified STEAP1 as a promising surrogate MRD marker of metastatic EFT with potential prognostic importance. Its clinical utility will need to be further tested in large patient cohorts.

No significant financial relationships to disclose.

Identification of candidate tumor related genes using comprehensive gene expression analysis of neuroblastic tumors

9051

Background: Neuroblastic tumors (NBTs) represent a heterogeneous and relatively well defined spectrum of neoplastic diseases. We performed gene expression analysis to molecularly characterize the distinct clinicobiological subtypes of NBTs. Methods: Gene expression analysis of 106 NBTs (10 ganglioneuromas, 10 stage 4s, 29 loco-regional (stages 1, 2, 3), and 57 stage 4) and 12 neuroblastoma cell lines was performed using Affymetrix Genechip Human Genome U95 Set Arrays. Differential expression between predefined groups of biological and clinical relevance was determined by differences >3 standard deviations between the means for groups, step-down permutation and false discovery rate methods. Results: Gene expression analysis of clinically defined groups including stage 4 infants versus children, metastatic versus non metastatic, and stroma poor loco-regional versus stage 4, revealed that many differentially expressed genes mapped to chromosomal regions with well described recurrent abnormalities in NBTs (chromosomes 1, 11, 17, 19 and X). Pairwise comparison analysis of biologically defined groups, including triploid versus diploid/tetraploid NBTs, identified significantly discriminating genes that map to the same chromosomal regions. Gene expression analysis of MYCN-amplified versus MYCN non amplified NBTs, confirmed a functional overrepresentation for genes involved in protein biosynthesis. Conclusions: Gene expression profile analysis of clinically and biologically relevant subgroups of NBTs revealed differential expression of genes at specific chromosomal regions known to have strong association between genetic alterations and NBT clinical features. The identification of altered expression helps to define critical chromosomal regions and identify tumor related candidate genes within each region.

No significant financial relationships to disclose.

High statistics measurement of the K+-->pi0e+nu (K+e3) branching ratio

E865 at the Brookhaven National Laboratory AGS collected about 70 000 K(+)(e3) events to measure the K(+)(e3) branching ratio relative to the observed K+-->pi(+)pi(0), K+-->pi(0)micro(+)nu, and K+-->pi(+)pi(0)pi(0) decays. The pi(0) in all the decays was detected using the e(+)e(-) pair from pi(0)-->e(+)e(-)gamma decay and no photons were required. Using the 2002 Particle Data Group branching ratios for the normalization decays, we obtain BR(K(+)(e3(gamma)))=(5.13+/-0.02(stat)+/-0.09(syst)+/-0.04(norm))%, where K(+)(e3(gamma)) includes the effect of virtual and real photons. This result is approximately 2.3sigma higher than the current Particle Data Group value. Implications for the V(us) element of the CKM matrix, and the matrix's unitarity are discussed.

Therapeutic benefit of blocking interleukin-6 activity with an anti-interleukin-6 receptor monoclonal antibody in rheumatoid arthritis: a randomized, double-blind, placebo-controlled, dose-escalation trial

OBJECTIVE

To investigate the safety and efficacy of MRA, a recombinant human anti-interleukin-6 (anti-IL-6) receptor monoclonal antibody of the IgG1 subclass that inhibits the function of IL-6, in patients with established rheumatoid arthritis (RA).

METHODS

A randomized, double-blind, placebo-controlled, dose-escalation trial was conducted in 45 patients with active RA, as defined by the American College of Rheumatology (ACR) revised criteria. Patients were sequentially allocated to receive a single intravenous dose of either 0.1, 1, 5, or 10 mg/kg of MRA or placebo. The primary efficacy end point was meeting the ACR 20% response criteria at week 2 after treatment.

RESULTS

Demographic features were similar between treatment groups. At week 2, a significant treatment difference was observed between the 5 mg/kg of MRA and placebo, with 5 patients (55.6%) in the MRA cohort and none in the placebo cohort achieving ACR 20% improvement. There was no statistically significant difference in the ACR 20% response between the other 3 MRA cohorts and placebo at week 2. The mean disease activity score at week 2 in those who received 5 mg/kg and 10 mg/kg of MRA was 4.8 and 4.7 (P < 0.001 and P < 0.001 by analysis of variance), respectively. These mean scores were statistically significantly lower than those in the 0.1- and 1-mg/kg MRA and the placebo cohorts (6.4, 6.2, and 7.0, respectively). The erythrocyte sedimentation rate and C-reactive protein values fell significantly in the 5- and 10-mg/kg MRA cohorts and normalized 2 weeks after treatment. Seventeen patients (5, 4, 6, 2, and 0 patients in the placebo, 0.1-, 1-, 5-, and 10-mg/kg MRA cohorts, respectively) required corticosteroid or disease-modifying antirheumatic drug treatment because of active disease before study end. They were regarded as nonresponders from the time they received these treatments. Diarrhea was the most common adverse event, occurring in 8% of patients. Seven patients (15.6%) reported a severe adverse event (3, 1, 2, and 2 patients in the placebo, 0.1-, 1-, and 10-mg/kg MRA cohorts). There were no serious adverse events that were thought to be related to the study drug.

CONCLUSION

This is the first randomized controlled trial showing that inhibition of IL-6 significantly improved the signs and symptoms of RA and normalized the acute-phase reactants. Further research with multiple dosing is necessary to define the most appropriate therapeutic regimen of MRA in RA.

Experimental study of the radiative decays K+-->mu(+)nue(+)e(-) and K+-->e(+)nue(+)e(-)

Experiment 865 at the Brookhaven Alternating Gradient Synchrotron obtained 410 K+-->e(+)nue(+)e(-) and 2679 K+-->mu(+)nue(+)e(-) events including 10% and 19% background. The branching ratios were measured to be [2.48+/-0.14(stat)+/-0.14(syst)]x10(-8) (m(ee)>150 MeV) and (7.06+/-0.16+/-0.26)x10(-8) (m(ee)>145 MeV), respectively. Results for the decay form factors are presented.

New measurement of K(+)(e4) decay and the s-pave pi pi-scattering length a(0)(0)

A sample of 4 x 10(5) events from the decay K(+)-->pi(+)pi(-)e(+)nu(e) (K(e4)) has been collected in experiment E865 at the Brookhaven Alternating Gradient Synchrotron. The analysis of these data yields new measurements of the K(e4) branching ratio [(4.11+/-0.01+/-0.11) x 10(-5)], the s-wave pi pi scattering length [a(0)(0) = 0.216+/-0.013(stat)+/-0.004(syst)+/-0.005(theor)], and the form factors F, G, and H of the hadronic current and their dependence on the invariant pi pi mass.

Search for lepton flavor violation in K+ decays into a charged pion and two leptons

A search for lepton flavor violating decays, K+ --> mu+ mu+ pi-, K+ --> e+ e+ pi-, K+ --> pi+ e+ mu-, K+ --> mu+ e+ pi-, and pi0 --> e+ mu-, was performed using the data collected in Experiment E865 at the Brookhaven Alternating Gradient Synchrotron. No signal was found in any of the decay modes. At the 90% confidence level, the branching ratios are less than 3.0x10(-9), 6.4x10(-10), 5. 2x10(-10), 5.0x10(-10), and 3.4x10(-9), respectively.

Improved limit on the rate of the decay K+ --> pi(+)&mgr;(+)e(-)

We report results of a search for the lepton-family number violating decay K+-->pi(+)&mgr;(+)e(-) from data collected by experiment E865 in 1996 at the Alternating Gradient Synchroton of Brookhaven National Laboratory. We place an upper limit on the branching ratio at 3.9x10(-11) ( 90% C.L.). Together with results based on data collected in 1995 and an earlier experiment, E777, this result establishes a combined 90% confidence level upper limit on the branching ratio at 2.8x10(-11). We also report a new upper limit on the branching ratio for pi(0)-->&mgr;(+)e(-) of 3.8x10(-10) ( 90% C. L.).

The angiopoietins, tie2 and vascular endothelial growth factor are differentially expressed in the transformation of normal lung to non-small cell lung carcinomas

The successful establishment of angiogenesis depends on a complex process of endothelial proliferation and organization. The angiopoietins (Ang-1 and Ang-2) and Tie2 ligand-receptor system is essential for the regulation of vascular maturation and stability during embryonic development. Together with the vascular endothelial growth factor (VEGF)-mediated pathway, they have been implicated in the control of normal physiological angiogenesis. We investigated their potential role and interaction in the development of lung cancers by comparing the expression pattern and inter-relationship of Ang-1 and 2, Tie2 and VEGF levels in 28 pairs of primary non-small cell lung cancers (NSCLC) and normal lung. Using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and in-situ hybridization (ISH), we showed that in NSCLC, there was significantly up-regulated VEGF expression by the tumour cells and an increased intensity of Ang-2 expression in the tumour vessels. The number of Ang-2-expressing vessels also correlated with the grades of tumour cell expression of VEGF. On the other hand, normal lung expressed constitutively high and correlated levels of Ang-1 and Tie2, which were significantly reduced in the carcinomas. The findings suggested a role of the Ang-1/Tie2 pathway in the maintenance of the complex vasculature in normal lung, while collaborative activities between the Ang-2 and VEGF pathways might be important in promoting tumour angiogenesis in NSCLC.

Expression and protein-binding studies of the EEN gene family, new interacting partners for dynamin, synaptojanin and huntingtin proteins

EEN, identified initially as a fusion partner to the mixed-lineage leukaemia gene in human leukaemia, and its related members, EEN-B1 and EEN-B2, have recently been shown to interact with two endocytic molecules, dynamin and synaptojanin, as well as with the huntingtin protein. In the present study, we show that the expression of the EEN gene-family members is differentially regulated. Multiple-spliced variants were identified for EEN-B2. In the brain, EEN-B1 and EEN-B2 mRNA are preferentially expressed in the cerebellar Purkinje and granule cells, dentate gyrus cells, hippocampal pyramidal neurons and cerebral granule cells. The expression patterns of EEN-B1 and EEN-B2 mRNA in the brain overlap with those of dynamin-I/III, synaptojanin-I and huntingtin, whereas the ubiquitous expression of EEN is consistent with that of dynamin-II. In testes, members of the EEN family are co-expressed with testis-type dynamin and huntingtin in Sertoli cells and germ cells respectively. Our results on the overlapping expression patterns are consistent with the proposed interaction of EEN family members with dynamin, synaptojanin and huntingtin protein in vivo. Although all three EEN family members bind to dynamin and synaptojanin, EEN-B1 has the highest affinity for binding, followed by EEN and EEN-B2. We also demonstrate that amphiphysin, a major synaptojanin-binding protein in brain, can compete with the EEN family for binding to synaptojanin and dynamin. We propose that recruitment of the EEN family by dynamin/synaptojanin to clathrin-coated pits can be regulated by amphiphysin.

The interaction between EEN and Abi-1, two MLL fusion partners, and synaptojanin and dynamin: implications for leukaemogenesis

The mixed lineage leukaemia gene, MLL (also called HRX, ALL-1) in acute leukaemia is fused to at least 16 identified partner genes that display diverse structural and biochemical properties. Using GST pull down and the yeast two hybrid system, we show that two different MLL fusion partners with SH3 domains, EEN and Abi-1, interact with dynamin and synaptojanin, both of which are involved in endocytosis. Synaptojanin, a member of the inositol phosphatase family that has recently been shown to regulate cell proliferation and survival, is also known to bind to Eps15, the mouse homologue of AF1p, another fusion partner of MLL. Expression studies show that synaptojanin is strongly expressed in bone marrow and immature leukaemic cell lines, very weakly in peripheral blood leukocytes and absent in Raji, a mature B cell line. We found that the SH3 domains of EEN and Abi-1 interact with different proline-rich domains of synaptojanin while the EH domains of Eps15 interact with the NPF motifs of synaptojanin. In vitro competitive binding assays demonstrate that EEN displays stronger binding affinity than Abi-1 and may compete with it for synaptojanin. These findings suggest a potential link between MLL fusion-mediated leukaemogenesis and the inositol-signalling pathway.

New measurement of the rare decay K+ --> pi(+)&mgr;(+)&mgr;(-)

More than 400 K+-->pi(+)&mgr;(+)&mgr;(-) events were observed in a rare K+ decay experiment at the Brookhaven Alternating Gradient Synchrotron. Normalized to the K+-->pi(+)pi(+)pi(-) decay, the branching ratio is determined to be [9.22+/-0.60(stat)+/-0. 49(syst)]x10(-8). This branching ratio and the &mgr;&mgr; mass spectrum is in very good agreement with the measurement of the K+-->pi(+)e(+)e(-) decay, but deviates significantly from the previous measurement.

Vascular endothelial growth factor is up-regulated in the early pre-malignant stage of colorectal tumour progression

Angiogenesis is an essential requirement for the development, progression and metastasis of malignant tumours. Studies on transgenic mouse models have shown that angiogenesis begins in the pre-malignant phase of oncogenesis, when dysplastic lesions acquire an increased microvasculature. To investigate the relationship between the expression of vascular endothelial growth factor (VEGF) and colorectal tumour progression, we have studied VEGF expression level and splice variant pattern by semi-quantitative RT-PCR and the cellular source of VEGF expression by in situ hybrization (ISH) in a range of lesions that modelled the tumour-development pathway from normal colon to invasive colorectal adenocarcinomas. Colonic adenomas showed a statistically significant up-regulation of VEGF expression over normal tissues, with a further increase during the development of adenocarcinomas. Tumour cells formed the major source of VEGF expression, with a minor contribution from mononuclear cells in the tumour stroma and enhanced expression in tumour cells around necrotic regions. The comparable expression level in both the in situ and invasive components in the same tumours indicated that a high VEGF expression capacity had been acquired prior to establishment of the invasive phenotype. Our findings support activation of VEGF as the molecular basis for the discrete induction of angiogenesis in the pre-malignant phase of colorectal tumour development.

Vascular endothelial growth factor is up-regulated in the early pre-malignant stage of colorectal tumour progression

Angiogenesis is an essential requirement for the development, progression and metastasis of malignant tumours. Studies on transgenic mouse models have shown that angiogenesis begins in the pre-malignant phase of oncogenesis, when dysplastic lesions acquire an increased microvasculature. To investigate the relationship between the expression of vascular endothelial growth factor (VEGF) and colorectal tumour progression, we have studied VEGF expression level and splice variant pattern by semi-quantitative RT-PCR and the cellular source of VEGF expression by in situ hybrization (ISH) in a range of lesions that modelled the tumour-development pathway from normal colon to invasive colorectal adenocarcinomas. Colonic adenomas showed a statistically significant up-regulation of VEGF expression over normal tissues, with a further increase during the development of adenocarcinomas. Tumour cells formed the major source of VEGF expression, with a minor contribution from mononuclear cells in the tumour stroma and enhanced expression in tumour cells around necrotic regions. The comparable expression level in both the in situ and invasive components in the same tumours indicated that a high VEGF expression capacity had been acquired prior to establishment of the invasive phenotype. Our findings support activation of VEGF as the molecular basis for the discrete induction of angiogenesis in the pre-malignant phase of colorectal tumour development.

Tissue-specific expression pattern of vascular endothelial growth factor isoforms in the malignant transformation of lung and colon

Angiogenesis, a prerequisite for tumor growth and progression, results from a shift in the equilibrium between angiogenic factors and angiogenic inhibitors. Vascular endothelial growth factor (VEGF) has been identified as one of the most important factors mediating angiogenesis in physiological and pathological conditions. Through alternative splicing, four isoforms of VEGF are formed, consisting of 206, 189, 165, and 121 amino acids, respectively. VEGF206 and VEGF189 differ from VEGF165 and VEGF121 in their bioavailability, with the longer forms being matrix-bound and the shorter forms freely diffusible. To investigate the relative importance of the VEGF isoforms in neoplastic transformation, we studied the pattern of splice variant expression by reverse transcription polymerase chain reaction (RT-PCR) in 18 lung and 11 colonic carcinomas and their corresponding normal tissues, respectively. The findings showed a significant upregulation of VEGF in both carcinomas, with VEGF165 and VEGF121 being the predominant forms; VEGF189 was significantly expressed in normal lung but not colon; and VEGF206 was not detected in any specimen. The findings indicate that during malignant progression, an angiogenic switch favoring the shorter diffusible isoforms is likely to confer on the tumor a growth advantage. From the differential expression of VEGF isoforms in normal lung and colonic tissues, different functional roles of the splice variants is suggested. In particular, VEGF189 may be important for the maintenance of the vascular integrity of the lung.

Expression of vascular endothelial growth factor and its receptors in the anaplastic progression of astrocytoma, oligodendroglioma, and ependymoma

Vascular endothelial growth factor (VEGF) is a hypoxia-inducible angiogenic factor, which is known to be upregulated in most cases of glioblastoma multiforme (GBM). The expression of VEGF and its receptors in ependymomas, oligodendrogliomas, and particularly the expression during anaplastic progression of these three types of gliomas has not been studied extensively. Fifty-six gliomas, consisting of 10 ependymomas, 12 oligodendrogliomas, 3 anaplastic oligodendrogliomas, 6 astrocytomas grade II, 5 anaplastic astrocytomas, and 20 glioblastoma multiformes, were investigated for VEGF and receptor expression using in situ hybridization (ISH) and reverse transcription polymerase chain reaction (RT-PCR). Results showed that VEGF was moderately to strongly expressed in 8 of 10 ependymomas and in all anaplastic oligodendrogliomas and glioblastoma multiforme cases. These tumors displayed similar degrees of extensive necrosis and vascular proliferation, with VEGF expression consistently seen in tumor cells around necrotic areas. The VEGF expression, although present at a lower level, also was shown in 4 of 12 oligodendrogliomas, in 3 of 6 astrocytomas grade II, and in 2 of 5 anaplastic astrocytomas, with a regional rather than diffuse pattern of positive result. The findings from the in situ hybridization study correlated with the expression index, as determined by reverse transcription polymerase chain reaction. Expression of VEGF was correlated significantly with vascular proliferation (p < 10(-5)) and necrosis (p < 10(-5)), as well as with microvessel density (p = 0.002, rs = 0.41). The VEGF receptors, kinase domain region (KDR) and Fms-like-tyrosine kinase (Flt-1), also were upregulated in the tumor vasculature of glioblastoma multiforme, anaplastic oligodendrogliomas, and ependymomas with necrosis, whereas the astrocytomas grade II, anaplastic astrocytomas, and oligodendroglioma tumors tended to express a weak to nondetectable signal. Anaplastic progression in all three types of gliomas is heralded by the occurrence of small zones of VEGF-expressing cells and early vascular proliferation, followed by an accelerated phase of angiogenesis closely associated with VEGF induction around areas of necrosis and with the expression of VEGF receptors in the tumor vasculature.

Up-regulation of lysozyme production in colonic adenomas and adenocarcinomas

AIMS

The presence of lysozyme protein in some gastric adenomas and adenocarcinomas has been well documented. There have been relatively few studies investigating the presence of lysozyme in tumours of the large intestine and they show contrasting results. We aim to investigate the cellular source and expression of lysozyme in colonic adenomas and adenocarcinomas.

METHODS AND RESULTS

We randomly selected 29 and 27 colonic adenomas and adenocarcinomas, respectively. Using in-situ hybridization (ISH) and immunohistochemistry (IHC), we found an up-regulation of lysozyme in the dysplastic epithelium of all the adenomas studied, with more than 80% of cases expressing moderate to strong signals. Although the up-regulation of lysozyme was also observed in adenocarcinomas, only 30% of the cases showed moderate to strong signals, mostly with an uneven distribution. Down-regulation of lysozyme in the severely dysplastic and invasive foci were noted in some cases of adenoma with malignant transformation. Normal colonic glands were consistently negative for lysozyme at both the mRNA and the protein level, but inflamed and immature regenerative colonic epithelium at the crypt base showed positive signals in a similar pattern to those observed in the dysplastic epithelium of the adenomas.

CONCLUSIONS

Our results confirm that colonic epithelium can produce lysozyme and its expression is up-regulated in the dysplastic epithelium in adenomas and in invasive cancer cells. It is interesting that regenerative colonic epithelium showed a similar pattern of lysozyme expression as in adenomas. The loss of lysozyme secreting phenotype in most of the invasive tumours suggests that lysozyme may not confer an advantage to tumour progression.

Expression of vascular endothelial growth factor and its receptors in pilocytic astrocytoma

Vascular endothelial growth factor (VEGF), a potent angiogenic and vascular permeability factor, is important in the angiogenesis of glioblastoma. A major difference between pilocytic astrocytoma, a grade I tumor, and the grade II fibrillary astrocytoma is the vascular proliferation, highly vascularized stroma, and great propensity for cyst formation in the former. In order to explore factors regulating such angiogenesis and cyst formation in pilocytic astrocytoma, we examined expression of VEGF and its receptors (KDR and Flt-1) using in situ hybridization. In all 14 cases a high level of VEGF transcripts could be demonstrated. These were found in specific regions, namely, in the tumor cyst wall, in areas of hyaline cystic degeneration, in stellate reticulated astrocytes around microcysts in the biphasic compact and loose areas, and in tumor cells with degenerative pleomorphic multicoated nuclei. KDR and Flt-1 were expressed in the tumor vasculature, with particularly high levels seen in coiled young proliferating vessels, especially those in the cyst wall. Given the known angiogenic and vascular permeability activities of VEGF, we propose that VEGF plays an important role in molding the characteristic morphologic features of this tumor, namely, the formation of cysts, microcystic pattern, hyaline cystic degeneration, hyaline vessels, and vascular proliferation. Mechanisms that block the VEGF pathway could constitute a potential therapeutic strategy for the treatment of this tumor.

Looking at dietary effects on weight loss and diarrhea in HIV seropositive patients: a pilot project

This was a pilot study and therefore only gives us information as to the direction that we can continue looking towards. There were two factors that could have skewed the results. One is the small size of the sample group and the other is that in the Nutritionist III program, not every nutrient, especially in the case of a trace mineral such as selenium, is listed in all foods. Further research is certainly warranted in this area to advance the study of the long term effects of a nutritional intervention on long-term survival of HIV/AIDS persons. A theory was published by the Journal of Medicinal Chemistry (Aug. 1994) that the HIV virus slowly depletes the body of the trace mineral selenium, which it uses to erupt into uninfected cells. The theory proposes that the HIV virus needs selenium, which preserves the elasticity of body tissue and slows the aging process, to trigger its growth. Once the virus uses up all the selenium in one cell, then it breaks out in search of more, spreading the infection to new cells. The researchers at the University of Georgia suggested that the latency period may be attributed to the period of time it takes to deplete the body of selenium storage. (NY Times, Aug. 20, 1994)

Intravenous gammaglobulin treatment of chronic idiopathic thrombocytopenic purpura

High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen.