Biomedical subjects

S Rea

Publications and source records attributed to S Rea.

At least 37 records · Page 2Linked to original sources

PubMed2001

Combined 5-fluorouracil infusion with fractionated epirubicin and cyclophosphamide in advanced breast cancer.

5-Fluorouracil (5-FU) given by continuous infusion (c.i.) allows higher dose delivery, causes less myelosuppression, and may interfere with repair of DNA damage caused by epirubicin and cyclophosphamide. With this rationale, we conducted a phase II study to test the activity and toxicity of 5-FU c.i., epirubicin, and cyclophosphamide in patients with metastatic breast cancer (MBC). Twenty-eight patients with MBC were entered in the trial. 5-FU (200 mg/m(2)) was administered by c.i. from day 1 to day 20. Epirubicin (35 mg/m(2)) and cyclophosphamide (400 mg/m(2)) were administered from day 2 to day 4, every 4 weeks. All patients were evaluable for response and toxicity. A total of 125 courses of chemotherapy were administered, with a median of 4 per patient (range: 2--6). Toxicity, assessed using World Health Organization criteria, was as follows: nausea and vomiting grade III--IV occurred in 36%, alopecia (grade III) in 86%, neutropenia (grade III--IV) in 50%, and cardiac toxicity grade I--II in 11% of patients. Five patients (17.9%) had a complete response to therapy, and 16 (57.1%) had a partial response (response rate 75%, 95% CI 55--89%). Disease stability and progression occurred in 4 (14.3%) and 3 (10.7%) patients, respectively. Median time to progression was 13.1 months (range: 3.4--66.9+), and median survival time was 27.7 months (range: 5.4--67.1+). Outpatient treatment with combined 5-FU c.i., epirubicin, and cyclophosphamide shows high activity in advanced breast cancer and gives prolonged remission with acceptable toxicity.

Adult↗

PubMed2001

Phase 1B study of subcutaneously administered interleukin 2 in combination with 13-cis retinoic acid as maintenance therapy in advanced cancer.

At present, no therapeutic strategy is available to maintain responses achieved in patients treated with chemotherapy. This Phase IB study was aimed at identifying the optimal biological dose of chronic maintenance therapy using s.c. interleukin (IL) 2 and oral 13-cis retinoic acid (RA) in patients with either tumor stabilization or response to chemotherapy. IL-2 has no cross-resistance with chemotherapy and improves cancer-related lymphocytopenia, a factor that determines poor prognosis, whereas RA has immunomodulatory properties, potentially synergistic with IL-2. Eighteen patients with advanced solid tumor who achieved a response or stable disease as a result of standard chemotherapy, received RA (0.5 mg/kg) and IL-2 5 days/week for two cycles of 3 weeks/month for up to 1 year. Three doses of IL-2 were used: 9.0, 4.5, and 1.8 x 10(6) IU/day. Monitoring consisted in a weekly blood differential count and a bimonthly assessment of tumor markers, CD4+, CD8+, and natural killer cells. Patients were evaluated for toxicity, response maintenance, time to progression, and survival. Patients chronically treated with 9 and 4.5 x 10(6) IU of IL-2 developed dose-limiting toxicity grade III or IV, consisting of fever, fatigue, thrombocytopenia, mucositis, and local cutaneous reaction. No grade III or IV toxicity was observed with the 1.8 x 10(6) IU dose, considered as the optimal biological dose. Fifty courses of IL-2 were administered (median, 3 per patient). An increase in total lymphocyte number, CD4:CD8 ratio and natural killer cell count was observed at all of the three dose levels with respect to baseline values. Two patients with a partial response to chemotherapy achieved a complete response after 6 and 7 months, respectively, of IL-2 + RA maintenance therapy. Median time to progression and overall survival were, respectively, 8.1 and 13.7 months (range, 2-48.8+ months). Low-dose IL-2 + RA as maintenance therapy after chemotherapy is, therefore, feasible and well tolerated and improves immunological parameters known to have a prognostic value in cancer.

Adult↗

PubMed2001

Primary chemotherapy in stage IV ovarian cancer. A prospective phase II study.

BACKGROUND AND RATIONALE: Non-curative surgical cytoreduction of advanced tumors is associated with increased proliferation of the remaining tumor cells. Thus, appropriate preoperative chemotherapy should prevent both cell proliferation and the increase of resistant cells. The aim of the present study was to evaluate the efficacy and toxicity of primary chemotherapy (P-CT) in previously untreated patients with stage IV ovarian cancer (OC). PATIENTS AND METHODS: Thirty-four patients with stage IV OC were treated from January 1993 to April 2000 with P-CT. Eligibility criteria included: histologically or cytologically confirmed, unresectable stage IV OC and performance status < or = 3. P-CT consisted of four courses of carboplatin, cyclophosphamide and epirubicin until October 1996, and paclitaxel, carboplatin thereafter. Surgery followed P-CT. After the operation patients received two further courses of chemotherapy that were tailored according to their individual response. Median (M) age was 61 years, range 32-73; median performance status was 2. A total number of 197 courses of CT were administered, median 5.7 per patient. RESULTS: Complete or partial response (CR, PR) was observed in 28 patients (response rate 82%, 95% CI: 65.4% to 93.2%), disease stability and progression (SD, PD) was observed in three and three patients, respectively. Median time to progression was 16.45 months (range 4.8-90.4+), median survival time was 28 months (range 4.5 - 90.4+): 1-year survival rate was 94%. Toxicity according to WHO: nausea and vomiting grade (G) 2, 30% of patients; gastrointestinal G 2-3, 20% of patients; alopecia G 3, 88% of patients; hematological G 3-4, 73% of patients; neurologic G 2, 12% of patients. Nine pathological CRs were observed. CONCLUSION: Neoadjuvant treatment with CBDCA with either CTX and EPI or Taxol is feasible and shows activity in OC.

Adult↗

PubMed2000

Regulation of chromatin structure by site-specific histone H3 methyltransferases.

The organization of chromatin into higher-order structures influences chromosome function and epigenetic gene regulation. Higher-order chromatin has been proposed to be nucleated by the covalent modification of histone tails and the subsequent establishment of chromosomal subdomains by non-histone modifier factors. Here we show that human SUV39H1 and murine Suv39h1--mammalian homologues of Drosophila Su(var)3-9 and of Schizosaccharomyces pombe clr4--encode histone H3-specific methyltransferases that selectively methylate lysine 9 of the amino terminus of histone H3 in vitro. We mapped the catalytic motif to the evolutionarily conserved SET domain, which requires adjacent cysteine-rich regions to confer histone methyltransferase activity. Methylation of lysine 9 interferes with phosphorylation of serine 10, but is also influenced by pre-existing modifications in the amino terminus of H3. In vivo, deregulated SUV39H1 or disrupted Suv39h activity modulate H3 serine 10 phosphorylation in native chromatin and induce aberrant mitotic divisions. Our data reveal a functional interdependence of site-specific H3 tail modifications and suggest a dynamic mechanism for the regulation of higher-order chromatin.

Amino Acid Sequence↗

PubMed2000

360 degrees laparoscopic fundoplication with tension-free hiatoplasty in the treatment of symptomatic gastroesophageal reflux disease.

BACKGROUND: Since laparoscopic Nissen fundoplication was first described by Cuschieri in 1989 and later by Dallemagne in 1991, this procedure has been widely employed for the treatment of symptomatic gastroesophageal reflux disease (GERD) and/or hiatal hernia. However, a relatively high incidence (7-11%) of intrathoracic Nissen valve migration/paraesophageal hernia following laparoscopic fundoplication has recently been reported. METHODS: Between November 1992 and August 1995, 65 consecutive patients with severe GERD and/or hiatal hernia underwent laparoscopic 360 degrees fundoplication. In nine of these 65 (13.8%) patients, an intrathoracic Nissen valve migration had occurred within 4 months. Six of these patients were symptomatic and were again submitted to the laparoscopic intervention. Videotapes of both the first and second operation were reviewed. In all cases, it was apparent that, at the first operation, closure by stitches of the hiatus was under tension, and at the second operation, the muscle fibers of the right crus were disrupted, probably due to the tension between the suture margins during the inspiratory movements of the diaphragm. These findings prompted us to perform an effective tension-free closure of the hiatus. A polypropylene mesh (3 x 4 cm) was placed on the hiatus behind the esophagus and fixed with eight metallic agraphes (2 + 2 on the superior edge and 2 + 2 on the lateral sides of the right and left cruses). RESULTS: Between August 1995 and February 1998, the technique, complete with 360 degrees fundoplication, was used for 67 patients with GERD. At mean follow-up of 22.5 months (range, 1-30), there was no evidence of postoperative paraesophageal hernia or complications related to the use of the mesh. CONCLUSIONS: This tension-free hiatoplasty seems to be an effective solution to prevent postoperative paraesophageal hernia in patients undergoing antireflux laparoscopic surgery. However, longer follow-up is still needed.

Adolescent↗

PubMed2000

Randomized trial of sequential administration of G-CSF and GM-CSF vs. G-CSF alone following peripheral blood progenitor cell autograft in solid tumors.

A trial was conducted to investigate whether the sequential administration of recombinant human granulocyte colony-stimulating factor (G-CSF) and recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) could accelerate reconstitution of hematopoiesis, compared with G-CSF alone following high-dose chemotherapy (HDCT). A group of 34 consecutive patients with solid tumors undergoing HDCT and autologous peripheral blood progenitor cell (PBPC) transplantation was studied. Conditioning regimen included carboplatin, etoposide, mitoxantrone, and melphalan for breast cancer and cyclophosphamide or ifosfamide, carboplatin, and etoposide for the other tumors. HDCT was delivered from day -3 to day -1. PBPC were infused on day 0, and on the same day growth factors were administered subcutaneously (s.c.) 5 microg/kg each. Seventeen patients were randomized to receive G-CSF from day 0 to day 13 after HDCT (arm A), and 17 patients received G-CSF from day 0 to day 6 and GM-CSF from day 7 to day 13 (arm B). Patients were stratified, and their characteristics were homogeneous in both arms for age, performance status, and number of previous chemotherapy courses and CD34+ infused. The median time to absolute neutrophil count (ANC) >500/microl was 10 days in arm A and 9 days in arm B (p = 0.96). Days to platelet (PLT) count >20,000 were not different in the two treatment arms (p = 0.1), but patients randomized to arm A had a lower platelet count compared with patients in arm B. One month after PBPC transplantation, a statistically significant difference in PLT count was observed (arm A median 150x10(3)/microl (90-310), arm B median 254x10(3)/microl (117-387),p = 0.0013). The days patients had fever >38 degrees C were 39 in arm A and 26 in arm B (p = 0.18). The difference in the length of hospital stay was not statistically significant between the groups (Mann-Whitney sum rank test). After a median follow-up of 30 months, 21 patients were alive and 20 were disease free. These data show that the two growth factors are associated with different patterns of hematopoietic recovery, and larger randomized trials in groups of more homogeneous patients will be needed to define the effects and benefits of combination growth factor therapies.

Adolescent↗

PubMed2000

Isolation and characterization of Suv39h2, a second histone H3 methyltransferase gene that displays testis-specific expression.

Higher-order chromatin has been implicated in epigenetic gene control and in the functional organization of chromosomes. We have recently discovered mouse (Suv39h1) and human (SUV39H1) histone H3 lysine 9-selective methyltransferases (Suv39h HMTases) and shown that they modulate chromatin dynamics in somatic cells. We describe here the isolation, chromosomal assignment, and characterization of a second murine gene, Suv39h2. Like Suv39h1, Suv39h2 encodes an H3 HMTase that shares 59% identity with Suv39h1 but which differs by the presence of a highly basic N terminus. Using fluorescent in situ hybridization and haplotype analysis, the Suv39h2 locus was mapped to the subcentromeric region of mouse chromosome 2, whereas the Suv39h1 locus resides at the tip of the mouse X chromosome. Notably, although both Suv39h loci display overlapping expression profiles during mouse embryogenesis, Suv39h2 transcripts remain specifically expressed in adult testes. Immunolocalization of Suv39h2 protein during spermatogenesis indicates enriched distribution at the heterochromatin from the leptotene to the round spermatid stage. Moreover, Suv39h2 specifically accumulates with chromatin of the sex chromosomes (XY body) which undergo transcriptional silencing during the first meiotic prophase. These data are consistent with redundant enzymatic roles for Suv39h1 and Suv39h2 during mouse development and suggest an additional function of the Suv39h2 HMTase in organizing meiotic heterochromatin that may even impart an epigenetic imprint to the male germ line.

Amino Acid Sequence↗

PubMed1999

Radioiodine-induced changes in lymphocyte subsets in patients with differentiated thyroid carcinoma.

This study evaluated changes in lymphocyte subsets in patients with thyroid carcinoma who received iodine-131 for diagnostic and therapeutic purposes. Twenty thyroid cancer patients were entered in the study after total thyroidectomy: ten patients (group A) underwent whole-body scintigraphy with 185 MBq of (131)I and the other ten (group B) received 3700 MBq of (131)I therapy. All patients were in a hypothyroid state at the time of administration of (131)I and started L-thyroxine 150 microg/day 3 days after (131)I administration. Free and bound triiodothyronine and thyroxine, thyroid-stimulating hormone, thyroglobulin, thyroglobulin antibodies, thyroid peroxidase/microsomal antibodies, white blood cell, lymphocyte counts and lymphocyte subsets were serially determined at baseline and at days 2, 7, 15, 30 and 60 after (131)I administration. Twenty healthy age- and sex-matched individuals were used as a reference population for lymphocyte subset values. In group A only a reduction in NK cells at days 7 (P=0.043) and 15 (P=0.037) was observed. In group B, patients showed a delayed reduction in the total lymphocyte count at days 15, 30 and 60 (P=0.008, 0.004 and 0. 018, respectively), and a decrease in B cells throughout the study (at days 7, 15, 30 and 60: P=0.006, 0.0017, 0.0017 and 0.0017 respectively). A transient decrease in NK cells was observed at days 15 (P=0.025) and 30 (P=0.008). Among T cells, the helper phenotype (CD4+) was mainly affected, resulting in a reduction in the CD4+/CD8+ ratio at day 60 (P=0.046). Comparing the two groups, the numbers of B lymphocytes at day 30 (P=0.023) and NK cells at days 2 (P=0.037) and 30 (P=0.023) were significantly lower in group B. Neither group showed any clinical sign of immunosuppression during the follow-up period. In patients with thyroid cancer the sensitivity of lymphocytes to the effects of (131)I administered for diagnostic or therapeutic purposes depends upon lymphocyte phenotype and (131)I activity. NK cells are the most radiosensitive cells, being reduced even by low (131)I activity. At higher activity all subtypes show a reduction, which is more marked and prolonged for B lymphocytes and, to a lesser extent, for T-helper lymphocytes. These changes do not result in clinically relevant immunosuppression.

Adenocarcinoma, Follicular↗

PubMed1999

Ifosfamide, vinorelbine and gemcitabine in advanced non-small cell lung cancer. A phase I study.

The objective of this phase I study was to identify the maximum tolerated dose (MTD) and toxicity of a three drug, platinum-free regimen, including gemcitabine, ifosfamide and vinorelbine, in the treatment of patients with advanced non-small cell lung cancer (NSCLC). 33 chemotherapy-naïve patients with histologically confirmed, unresectable NSCLC, received fixed doses of ifosfamide (1500 mg/m2 days 1-3 with mesna) and vinorelbine (25 mg/m2 days 3 and 8). The gemcitabine dose was escalated from 500 to 1200 mg/m2 on days 3 and 8 every third week. The escalation was stopped at dose level 4 (gemcitabine 1200 mg/m2) since all 3 patients of this cohort showed dose-limiting thrombocytopenia and/or neutropenia at treatment cycle 1. The dose recommended for phase II trials is: gemcitabine 1000 mg/m2 and vinorelbine 25 mg/m2 given on days 3 and 8 plus ifosfamide 1500 mg/m2 on days 1-3. An encouraging response rate of 50% (95% confidence interval (CI): 32-68%) was observed in 32 patients evaluated. Our results show that ifosfamide, vinorelbine and gemcitabine can be safely administered as outpatient chemotherapy for NSCLC. Myelosuppression is the dose-limiting toxicity (DLT) of this regimen with no major subjective side-effects observed.

Adult↗

PubMed1999

Carboplatin, ifosfamide, and vinorelbine in the treatment of advanced non-small-cell lung cancer: a phase II study.

The authors evaluated the efficacy and toxicity of the combination of carboplatin, ifosfamide, and vinorelbine in the treatment of advanced non-small-cell lung cancer. From March 1994 through March 1996, 56 previously untreated patients with stage IIIB or stage IV non-small-cell lung cancer with measurable lesions and good performance status were entered in the study. The chemotherapy schedule was as follows: carboplatin 100 mg/m2 and ifosfamide 1,500 mg/m2 with mesna on days 1, 2, and 3; vinorelbine 25 mg/m2 on days 1 and 8, every 21 days; for a total of six courses. Among 55 evaluable patients there were three complete responses (5%) and 22 partial responses (40%), for a response rate of 45% (95% confidence interval, 32-59%). The median response duration was 10.3 months (range, 2.5-27.7 months), and median survival time was 11.3 months (range, 1.1-28.1 months). The survival rate at 1 year was 48%. Toxicity included hematologic toxicity in 60% of the 247 treatment cycles administered, nausea, alopecia, and neuropathy. One pathologic complete response was observed in a patient with stage IIIB disease who became operable after four courses of chemotherapy. The outpatient treatment with carboplatin, ifosfamide, and vinorelbine shows activity in advanced non-small-cell lung cancer. The toxicity was well tolerated by patients with a good performance status.

Adult↗

PubMed1999

Myocardial 123I-MIBG kinetics in acutely hypothyroid patients with differentiated thyroid carcinoma.

Marked changes in cardiac function have been noted in patients with hyperthyroidism or hypothyroidism due both to changes in sympathetic system function and to biochemical modifications of myocardial tissue. Metaiodobenzylguanidine (MIBG), an analogue of norepinephrine, can be used to evaluate myocardial sympathetic tone. Here, we report myocardial 123I-MIBG kinetics in patients with differentiated thyroid carcinoma undergoing acute hypothyroidism followed by hormonal replacement as part of their routine clinical follow-up. Ten patients with differentiated thyroid carcinoma in acute hypothyroidism (A) and on hormonal replacement with thyroxine (150 micrograms.day-1) and triiodothyronine (20 micrograms.day-1) (B) underwent scintigraphic imaging 20 min and 4 h after injection of 111 MBq of ultra-high specific activity 123I-MIBG. No patient had cardiac disease or was taking medications that could interfere with cardiac or autonomic system function. Cardiac MIBG kinetics (heart-to-mediastinum, H/M, ratio and myocardial washout rate), serum norepinephrine, T3, T4, FT3, FT4, TSH, CPK, CPK-MB, blood pressure and ECG were evaluated. Systolic and diastolic blood pressure did not differ significantly between state A and state B. In the acute hypothyroid state (A), the prevalence of non-specific ST-T abnormalities was 70% and heart rate was significantly different (P < 0.001) than in state B. Norepinephrine and CPK-MB levels were higher during hypothyroidism, but this did not reach statistical significance. A positive correlation between early H/M and delayed H/M in the hypothyroid state (r = 0.57) and an even higher positive correlation between early H/M and delayed H/M in the euthyroid state (r = 0.91) were seen. The myocardial and mediastinal MIBG washout rates were significantly different between the hypothyroid and euthyroid states (P < 0.05), whereas the lung washout rate did not differ significantly between the two metabolic states. We conclude that the myocardial washout rate during hypothyroidism is clearly increased (P < 0.005) with a subclinical derangement of myocardial adrenergic innervation, which is rapidly reversed with hormonal therapy.

3-Iodobenzylguanidine↗

PubMed1999

"Tension-free" hiatoplasty, gastrophrenic anchorage, and 360 degrees fundoplication in the laparoscopic treatment of paraesophageal hernia.

In our initial experience of four cases from March to November 1994, large paraesophageal hernias were repaired by conventional primary closure of the hiatus with interrupted, nonabsorbable sutures, adding a 360 degrees fundoplication. In all four cases the hernia recurred. Subsequently, we modified the procedure. The technique and results are described. From March 1995 to May 1998, 12 patients with paraesophageal hernia (4 following a previous Nissen procedure) underwent elective laparoscopic repair. In all patients a "tension-free" hiatoplasty and a floppy 360 degrees fundoplication were performed. The hiatal defect was repaired with a polypropylene mesh, fixed to the diaphragm by staples. A gastrophrenic anchorage procedure was added in the eight patients undergoing surgery for the first time, utilizing the peritoneum of the hernia sac. There were no conversions to open surgery or intraoperative complications. Two patients developed postoperative pleural effusion, which was treated medically. Mean hospital stay was 5 days. Three patients developed postoperative transient dysphagia to solid food that lasted 10 days. At a mean follow-up of 22.7 months (range 1-40), all patients are asymptomatic without dysphagia, reflux, or hernia recurrence. Laparoscopic "tension-free" hiatoplasty, 360 degrees fundoplication, and anterior gastrophrenic anchorage are effective in the treatment of large paraesophageal hernias.

Adult↗

PubMed1998

Syndet, an adipocyte target SNARE involved in the insulin-induced translocation of GLUT4 to the cell surface.

In adipocytes, insulin stimulates the translocation of the glucose transporter, GLUT4, from an intracellular storage compartment to the cell surface. Substantial evidence exists to suggest that in the basal state GLUT4 resides in discrete storage vesicles. A direct interaction of GLUT4 storage vesicles with the plasma membrane has been implicated because the v-SNARE, vesicle-associated membrane protein-2 (VAMP2), appears to be a specific component of these vesicles. In the present study we sought to identify the cognate target SNAREs for VAMP2 in mouse 3T3-L1 adipocytes. Membrane fractions were isolated from adipocytes and probed by far Western blotting with the cytosolic portion of VAMP2 fused to glutathione S-transferase. Two plasma membrane-enriched proteins, p25 and p35, were specifically labeled with this probe. By using a combination of immunoblotting, detergent extraction, and anion exchange chromatography, we identified p35 as Syntaxin-4 and p25 as the recently identified murine SNAP-25 homologue, Syndet (mSNAP-23). By using surface plasmon resonance we show that VAMP2, Syntaxin-4, and Syndet form a ternary SDS-resistant SNARE complex. Microinjection of anti-Syndet antibodies into 3T3-L1 adipocytes, or incubation of permeabilized adipocytes with a synthetic peptide comprising the C-terminal 24 amino acids of Syndet, inhibited insulin-stimulated GLUT4 translocation to the cell surface by approximately 40%. GLUT1 trafficking remained unaffected by the presence of the peptide. Our data suggest that Syntaxin-4 and Syndet are important cell-surface target SNAREs within adipocytes that regulate docking and fusion of GLUT-4-containing vesicles with the plasma membrane in response to insulin.

3T3 Cells↗

PubMed1998

Minimal residual disease in metastatic breast cancer: treatment with IFN-beta, retinoids, and tamoxifen.

The aim of this pilot study was to investigate if chemotherapy (CT) followed by the combination of interferon-beta (IFN-beta), retinoids, and tamoxifen could be effective in the treatment of metastatic breast cancer (MBC). Thirty-six patients with stage IV carcinoma of the breast were treated with six courses of cyclophosphamide, 5-fluorouracil, 4-epidoxorubicin, vincristine, and prednisone every 3 weeks (FECPV), followed by two courses of non-cross-resistant drugs, methotrexate, mitomycin C, and mitoxantrone (MMM). Treatment was continued, in responders, with low dose IFN-beta, retinyl palmitate, and tamoxifen until relapse of the disease occurred. Among 36 evaluable patients, 23 achieved a clinical response (64 %) (95 % confidence interval [c.i.] 46 %-79 %), 7 had stable disease (19%), and 6 (17%) progressed. Leukopenia occurred in 15 patients, thrombocytopenia in 6, and anemia in 11. Sixteen patients had nausea/vomiting, stomatitis was observed in 9, and diarrhea occurred in 3. Toxicity from maintenance therapy was mild and mainly hepatic. Median response duration was 31 months (range 5-107). Median overall survival was 32 months (9-108). Our study shows that this combined approach for the treatment of MBC is feasible, with an acceptable toxicity.

Adult↗

PubMed1998

A novel synaptobrevin/VAMP homologous protein (VAMP5) is increased during in vitro myogenesis and present in the plasma membrane.

cDNA clones encoding a novel protein (VAMP5) homologous to synaptobrevins/VAMPs are detected during database searches. The predicted 102-amino acid VAMP5 harbors a 23-residue hydrophobic region near the carboxyl terminus and exhibits an overall amino acid identity of 33% with synaptobrevin/VAMP1 and 2 and cellubrevin. Northern blot analysis reveals that the mRNA for VAMP5 is preferentially expressed in the skeletal muscle and heart, whereas significantly lower levels are detected in several other tissues but not in the brain. During in vitro differentiation (myogenesis) of C2C12 myoblasts into myotubes, the mRNA level for VAMP5 is increased approximately 8- to 10-fold. Immunoblot analysis using antibodies specific for VAMP5 shows that the protein levels are also elevated approximately 6-fold during in vitro myogenesis of C2C12 cells. Indirect immunofluorescence microscopy and immunoelectron microscopy reveal that VAMP5 is associated with the plasma membrane as well as intracellular perinuclear and peripheral vesicular structures of myotubes. Epitope-tagged versions of VAMP5 are similarly targeted to the plasma membrane.

Amino Acid Sequence↗

PubMed1998

Advanced carcinoma of the pancreas: phase II study of combined chemotherapy, beta-interferon, and retinoids.

Because of the poor response of pancreatic cancer to conventional therapy, the authors performed a phase II pilot study to evaluate whether beta-interferon and retinoids, added to active chemotherapeutic agents, could increase response rate and survival in a group of patients who had metastatic disease. Twenty-three chemotherapy-naive patients were treated as follows: epirubicin, 60 mg/m2, and mitomycin C, 10 mg/m2, intravenously on day 1; folinic acid, 200 mg/m2, and 5-fluorouracil (5-FU), 370 mg/m2, intravenously for 5 consecutive days. beta-Interferon, 1 x 10(6) IU/m2, subcutaneously three times a week, and retinol palmitate, 50,000 IU orally twice a day, were given between chemotherapy cycles. Patients having responses and disease stabilization were maintained with the same dose of beta-interferon and retinol palmitate. Treatment was given every 4 weeks for four courses or until onset of progression. A median of three courses of chemotherapy was delivered to each patient. All patients were evaluable. Eight patients responded (35%) and 8 (35%) had stable disease. Median time to progression and survival for all patients were, respectively, 6.1 months and 11 months. Toxicity was severe: 60% of patients had hematologic toxicity, 40% had gastrointestinal toxicity, 13% had cardiac toxicity, and 1 patient had a hemolitic-uremic syndrome. The combination of chemotherapy, beta-interferon, and retinoids shows activity in metastatic pancreatic carcinoma. Toxicity was high but patients who had responses and disease stabilization had prolonged symptom palliation.

Adenocarcinoma↗

PubMed1997

Botulinum E toxin light chain does not cleave SNAP-23 and only partially impairs insulin stimulation of GLUT4 translocation in 3T3-L1 cells.

The stimulation of glucose uptake into fat and muscle by insulin results predominantly from the translocation of the glucose transporter, GLUT4, from an intracellular vesicle pool to the cell surface. Homologues of several key proteins known to be involved in the process of synaptic vesicle fusion have been identified on GLUT4 vesicles, including VAMP2 and cellubrevin. Syntaxin 4, SNAP-23 and/or SNAP-25 are also implicated in this process. Bacterial toxins that specifically cleave these proteins have been utilised to assess their involvement in cell function. We aimed to distinguish which of the SNAP isoforms are specifically involved in GLUT4 translocation. Here we show that both human (h) and mouse (m) SNAP-23, unlike SNAP-25, are not substrates for Botulinum E toxin light chain (BoNT/E). Furthermore, we demonstrate that microinjection of differentiated 3T3-L1 cells with BoNT/E inhibited insulin stimulation of GLUT4 translocation only slightly, 27%, whereas tetanus toxin light chain, that cleaves VAMP2, inhibited insulin stimulation of GLUT4 translocation by 80%. These studies therefore do not support a major role for SNAP-25 in insulin stimulation of GLUT4 translocation and place SNAP-23 as a prime candidate for a role in this process.

3T3 Cells↗

PubMed1997

Lung metastases of renal cell carcinoma: results of surgical resection.

OBJECTIVE: The research was designed to evaluate the results of surgical resection of renal lung metastases. METHODS: Between 1960 and 1994, 50 consecutive patients underwent resection for pulmonary metastases from renal cell carcinoma. Mean age was 59 years (range: 40-78 years). Mean time between nephrectomy and pulmonary resection was 3 years (range: 0-18 years). Nineteen patients had solitary metastase, 13 multiple unilateral, and 18 bilateral. Wedge excision was performed in 28 patients, segmentectomy in 3, lobectomy in 17, sleeve lobectomy in 1, pneumonectomy in 5 and biopsy in 3. Twelve patients had repeat resection for recurrent metastases. RESULTS: The resection was complete in 45 patients. Three patients also had a complete resection of limited extra-pulmonary disease. There was one postoperative death and 3 complications. Mean follow-up was 42 months without loss of follow-up. The cause of death was always metastatic recurrent disease. Five-year survival in complete resection was 44%. Only one long survivor was observed in the case of incomplete resection in a patient who had a complete response after adjuvant immunotherapy. Five-year survival for the 12 patients with repeat resections was similar to the overall survival rate (42%). CONCLUSIONS: Resection of renal lung metastases is a safe and effective treatment. No factor influenced the 5-year survival in this series except the complete resection. Extra-pulmonary metastases does not contra-indicate pulmonary resection. In selected patients, repeat resection for recurrent disease is warranted.

Actuarial Analysis↗