Colony-forming cells expressing high levels of CD34 are the main targets for granulocyte colony-stimulating factor and macrophage colony-stimulating factor in the human fetal liver

This study explores the perceptions of staff who have been practising primary nursing for more than 4 years in intensive care. It considers what primary nursing is, what its benefits, disadvantages, and role impact are and other issues within an intensive care setting from the staff's perceptions and experiences. Although many of the perceived advantages and disadvantages are similar to experiences from other areas of nursing, there are some differences. The differences seem to relate to the way primary nursing is practised within the research setting-each primary nurse works with the same small team of associates, which is perceived as providing added benefits in terms of personal support and development of junior staff. The changes in role are seen to reflect other models in the literature which focus on becoming more patient centred and on working therapeutically. A number of future issues are addressed.     

Cytokine regulation of granulocyte-macrophage colony stimulating factor and macrophage colony-stimulating factor production in human arterial smooth muscle cells

Smooth muscle cells (SMC) are the major cell type found in the walls of large blood vessels and appear to participate in local immune and inflammatory reactions, as well as in certain vascular diseases. We tested whether human arterial SMC can produce in vitro the colony stimulating factors (CSFs), granulocyte macrophage-CSF (GM-CSF) and macrophage CSF (M-CSF). Untreated internal mammary artery and aortic SMC produced no detectable GM-CSF but constitutively made M-CSF, measured by ELISA and radioimmunoassay, respectively. Interleukin-1 (IL-1) and, to a lesser extent, tumor necrosis factor alpha (TNF alpha) stimulated GM-CSF formation within 3 h; mRNA levels also increased particularly in the presence of the protein synthesis inhibitor, cycloheximide. IL-1, TNF alpha and, in addition, interferon-gamma (IFN-gamma) raised the M-CSF levels within 6 h; cycloheximide potentiated the effects of IL-1 and TNF alpha on mRNA levels. These results suggest that cytokine-stimulated human arterial SMC may be a source of the M-CSF found in atherosclerotic lesions. Since monocytes/macrophages can be activated by GM-CSF and M-CSF, while GM-CSF can also affect granulocyte function, SMC may participate in inflammatory reactions and vascular diseases by releasing these cytokines.     

Enhancement of in vitro and in vivo anti-tumor activity of anti-GD2 monoclonal antibody 220-51 against human neuroblastoma by granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor

Three new species of Eimeria are described from iguanid lizards of Central and South America. The oocysts of each species have no micropyles or residua and the sporocysts lack Stieda bodies, but all have a sporocyst residuum. Eimeria sanctaluciae n.sp. was found in the St. Lucia tree lizard, Anolis luciae, collected from the Maria Islands, Lesser Antilles. The oocysts are spherical to subspherical, averaging 17.3 x 16.5 microns, with a single layered colourless wall; about 60% contain polar granules. The sporocysts are ellipsoidal and average 7.7 x 5.5 microns. Eimeria liolaemi n.sp. was recovered from the blue-gold swift, Liolaemus taenius, from Chile. The oocysts are spherical to subspherical, measuring 21 x 20.1 microns with a single-layered colourless wall. The sporocysts are subspherical and average 7.4 x 6.8 microns. Eimeria caesicia n.sp. is described from the Brazilian collared iguanid, Tropidurus torquatus. The oocysts measure 27.4 x 23.7 microns, are spherical to subspherical, with a bilayered wall, the outer surface of which appears pale blue in colour, the thin, inner wall appearing brown, when viewed by direct light under the optical microscope. The sporocysts are subspherical and average 9.4 x 7.2 microns. Unnamed polysporocystid oocysts with dizoic sporocysts are reported from the faeces of the lesser St. Vincent tree lizard, Anolis trinitatis and the possibility of spurious parasitism briefly discussed. In addition, oocysts of an unnamed Isospora sp. with a smooth oocyst wall which closely resembles I. reui were recovered from A. trinitatis.     

Granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor and macrophage colony-stimulating factor in the treatment of acute myeloid leukemia and acute lymphoblastic leukemia

To explore the role of perfectionism across anxiety disorders, 175 patients with either panic disorder (PD), obsessive compulsive disorder (OCD), social phobia, or specific phobia, as well as 49 nonclinical volunteers, completed two measures [Frost, R. O., Marten, P., Lahart, C., & Rosenblate, R., (1990). The dimensions of perfectionism. Cognitive Therapy and Research, 14, 449-468; Hewitt, P. L., & Flett, G. L., (1991). Perfectionism in the self and social contexts: Conceptualization, assessment and association with psychopathology. Journal of Personality and Social Psychology, 60, 456-470.] that assess a total of nine different dimensions of perfectionism. Relative to the other groups, social phobia was associated with greater concern about mistakes (CM), doubts about actions (DA), and parental criticism (PC) on one measure and more socially prescribed perfectionism (SP) on the other measure. OCD was associated with elevated DA scores relative to the other groups. PD was associated with moderate elevations on the CM and DA subscales. The remaining dimensions of perfectionism failed to differentiate among groups. The clinical implications of these findings are discussed.     

CD16+ monocytes in patients with cancer: spontaneous elevation and pharmacologic induction by recombinant human macrophage colony-stimulating factor

The small subset of circulating monocytes that express the maturation-associated CD16 antigen has recently been reported to be elevated in patients with bacterial sepsis. We now show that this novel CD16+ monocyte population is also spontaneously expanded in patients with cancer. We studied 14 patients with metastatic gastrointestinal carcinoma enrolled ina clinical trial of recombinant human macrophage colony-stimulating factor (rhMCSF) plus monoclonal antibody D612. We found that before any cytokine treatment, 12 of 14 patients constitutively displayed significant elevations in both the percentage and the absolute number of CD16+ monocytes, as compared with both normal subjects and ill patients with elevated monocyte counts but without malignancy. CD16+ monocytes accounted for 46% +/- 22% of total monocytes in the patients with cancer versus 5% +/- 3% for controls (P < .01). The increase was not attributable to infection or intercurrent illness and appeared to be associated with the underlying malignancy itself. A similar spontaneous elevation of CD16+ monocytes was observed in 35 of 44 additional patients diagnosed with a variety of other solid tumors. When patients with gastrointestinal carcinoma were treated with rhMCSF, there was a marked further increase in the percentage of CD16+ monocytes (to 83% +/- 11%), as well as in the absolute number of CD16+ cells and the level of CD16 antigen expression. In every case, the patients with cancer showed a greater CD16+ monocyte response than the maximal response obtained in normal volunteer subjects treated witha similar regimen of rhMCSF (n = 5, P < .001), suggesting that the presence of malignancy primed patients for enhanced responsiveness to rhMCSF. We hypothesize that spontaneous expansion of the CD16+ monocyte population may represent a novel biologic marker for a widespread and previously unsuspected host immune response to malignancy.     

Preclinical evaluation of 111In-labeled B3 monoclonal antibody: biodistribution and imaging studies in nude mice bearing human epidermoid carcinoma xenografts

Biodistribution and imaging characteristics of monoclonal antibody B3 were evaluated in nude mice bearing A431 human epidermoid carcinoma xenografts. B3 is a murine IgG1k, recently isolated, reacting with a carbohydrate epitope abundantly and uniformly expressed by most carcinomas. B3 was conjugated to a new backbone-substituted derivative of diethylenetriaminepentaacetic acid, 2-(p-isothiocyanato benzyl)-cyclohexyl-diethylenetriaminepentaacetic acid, and labeled with 111In. Tumor-bearing mice were given i.v. injections of approximately 5 microCi of either 111In-B3 or 111In-MOPC-21, an isotype-matched control, and sacrificed in groups of five at 6 h and daily up to 168 h. Imaging was performed at 24, 72, and 144 h. Significant differences were observed in tumor uptake at all time points with peak values at 48 h (25 +/- 5.2% versus 6.3 +/- 0.4% of the injected dose/g tissue) (mean +/- SD) for 111In-B3 and 111In-MOPC-21, respectively (P < 0.001). All tumor to organ ratios increased with time for 111In-B3. In particular, tumor:liver ratios rose from 3.2 +/- 0.6 at 24 h to 6.3 +/- 1.2 at 168 h. Imaging results showed selective and progressive accumulation of 111In-B3 at the tumor site, whereas 111In-MOPC-21 did not show specific localization. In summary, 111In-labeled B3 demonstrated good and specific tumor targeting, which warrants its future clinical evaluation.     

The cancer growth suppressor gene mda-7 selectively induces apoptosis in human breast cancer cells and inhibits tumor growth in nude mice

A differentiation induction subtraction hybridization strategy is being used to identify and clone genes involved in growth control and terminal differentiation in human cancer cells. This scheme identified melanoma differentiation associated gene-7 (mda-7), whose expression is up-regulated as a consequence of terminal differentiation in human melanoma cells. Forced expression of mda-7 is growth inhibitory toward diverse human tumor cells. The present studies elucidate the mechanism by which mda-7 selectively suppresses the growth of human breast cancer cells and the consequence of ectopic expression of mda-7 on human breast tumor formation in vivo in nude mice. Infection of wild-type, mutant, and null p53 human breast cancer cells with a recombinant type 5 adenovirus expressing mda-7, Ad.mda-7 S, inhibited growth and induced programmed cell death (apoptosis). Induction of apoptosis correlated with an increase in BAX protein, an established inducer of programmed cell death, and an increase in the ratio of BAX to BCL-2, an established inhibitor of apoptosis. Infection of breast carcinoma cells with Ad.mda-7 S before injection into nude mice inhibited tumor development. In contrast, ectopic expression of mda-7 did not significantly alter cell cycle kinetics, growth rate, or survival in normal human mammary epithelial cells. These data suggest that mda-7 induces its selective anticancer properties in human breast carcinoma cells by promoting apoptosis that occurs independent of p53 status. On the basis of its selective anticancer inhibitory activity and its direct antitumor effects, mda-7 may represent a new class of cancer suppressor genes that could prove useful for the targeted therapy of human cancer.     

Comparative antitumor efficacy of docetaxel and paclitaxel in nude mice bearing human tumor xenografts that overexpress the multidrug resistance protein (MRP)

BACKGROUND: Multidrug resistance has been associated with expression of the multidrug resistance protein (MRP). Recently, MRP-expression has been detected in human tumor samples of patients with breast cancer and non-small-cell lung cancer. Since taxoids are the most active drugs in the treatment of both tumor entities, the antitumor efficacies of paclitaxel and docetaxel were compared in nude mice bearing human tumor xenografts that express MRP. MATERIALS AND METHODS: Athymic nude mice (nu/nu) bearing tumor xenografts of parental human sarcoma HT1080 or MRP-expressing HT1080/DR4 cells (as confirmed by Northern blot analysis) were treated with the maximum tolerated doses (MTD) of doxorubicin ([Dx] 10 mg/kg i.v. push), paclitaxel ([PC] 50 mg/kg three-hour i.v. infusion), or docetaxel ([DC] 40 mg/kg three-hour i.v. infusion). In vitro, the activity of doxorubicin, paclitaxel and docetaxel was evaluated by the sulphorhodamine B (SRB) assay using the pyridine analogue PAK-104P (5 microM), a potent inhibitor of MRP-function. RESULTS: At their MTDs both taxoids showed significant activity against MRP-negative HT1080 xenografts with response rates of 80% (40% CR) for PC and 100% (60% CR) for DC. In contrast, DC was significantly more active than PC in nude mice bearing doxorubicin resistant MRP-expressing HT1080/DR4 tumor xenografts (overall response rates: 100% (60% CR) for DC; 10% (0% CR) for PC; 0% for Dx). Since treatment of mice with the MTD of PC or DC yielded similar overall toxicity (maximum weight loss for HT1080: PC 8.6 +/- 2.2%; DC 7.5 +/- 2.2% and for HT1080/DR4: PC 11.6 +/- 3.0%; DC 7.6 +/- 1.8%, respectively), these results demonstrate the increase in the therapeutic index for docetaxel against MRP-expressing tumors. In vitro, HT1080/DR4 cells were 270-fold, 6.4-fold and 2.8-fold more resistant than parental cells to doxorubicin, PC and DC, respectively. Pyridine analogue PAK-104P completely restored drug sensitivity to PC and DC, while no effect of PAK-104P on parental HT1080 cells was observed. CONCLUSIONS: Both taxoids, when given at their MTDs, showed significant efficacy against parental HT1080 tumor xenografts. However, docetaxel at its MTD was significantly more active against MRP-expressing tumor xenografts than paclitaxel. Furthermore, in vitro resistance of HT1080/DR4 cells was higher for PC (6.4-fold) than for DC (2.8-fold). Since PAK-104P completely restored sensitivity to both taxoids, the observed resistance appears to be related to MRP. These data suggest, that docetaxel is not as readily transported by MRP as paclitaxel leading to an increased therapeutic ratio in MRP-expressing tumors in vivo. Therefore, docetaxel may have therapeutic advantages in the clinical treatment of MRP-expressing tumors.     

cAMP analogues downregulate the expression of granulocyte macrophage colony-stimulating factor (GM-CSF) in human bone marrow stromal cells in vitro

STUDY OBJECTIVE: To determine the neuromuscular blocking effect and recovery profile of cisatracurium besylate in children after administration of a bolus dose that was twice the estimated dose required to produce 95% of the maximum effect (2 x ED95; 0.08 mg/kg) followed by an infusion during halothane-nitrous oxide anesthesia. STUDY DESIGN: Open-label study. SETTING: Teaching hospital. PATIENTS: 30 male and female (ASA physical status I and II) patients, 2 to 10 years of age, scheduled for elective surgery of low to moderate risk. INTERVENTIONS: After induction of general anesthesia, patients received cisatracurium 0.08 mg/kg administered over 5 to 10 seconds. For surgical procedures requiring neuromuscular block for at least 60 minutes, a second bolus dose of cisatracurium 0.02 mg/kg was administered after the first response to a train-of-four stimuli (T1) recovered to 25% of baseline. When T1 was 5% of baseline after the second dose, a 3 microg/kg/min infusion of cisatracurium was initiated and titrated to maintain 89% to 99% block for the duration of the surgery. For procedures requiring neuromuscular block of less than 60 minutes, one or more maintenance doses of 0.02 mg/kg cisatracurium were administered when T1 was 25% of baseline after the preceding dose. In 10 patients, recovery was facilitated with edrophonium 1.0 mg/kg administered when T1 was 26% to 48% of the final baseline. MEASUREMENTS AND MAIN RESULTS: Evoked muscular response at the adductor pollicis was measured by electromyography. With 0.08 mg/kg, onset time (mean +/- SEM) was 4.1 +/- 0.4 minutes, and clinically effective duration was 27.3 +/- 0.9 minutes. Mean 5% to 95% and 25% to 75% recovery indices were 28.4 +/- 2. 7 minutes and 11.2 +/- 0.8 minutes, respectively. The mean infusion rate necessary to maintain 89% to 99% T1 suppression for 17 to 145 minutes was 1.7 microg/kg/min. After termination of infusion, the mean 5% to 95% and 25% to 75% recovery indices were similar to those after a single bolus dose, and time to 95% recovery was 30.4 +/- 3.0 minutes. After administration of edrophonium, full recovery (T4:T1 > or = 70%) occurred in 1.5 +/- 0.4 minutes. No clinically significant changes in heart rate or blood pressure were noted during the first 5 minutes after administration of cisatracurium 0.08 mg/kg. CONCLUSIONS: Cisatracurium provided maximal neuromuscular block, cardiovascular stability, and predictable recovery at the doses tested. In view of this finding, cisatracurium should be a useful intermediate-duration neuromuscular blocking drug for children during general anesthesia.     

Enhancement of cytosine arabinoside cytotoxicity by granulocyte/macrophage colony-stimulating factor and granulocyte colony-stimulating factor in a human myeloblastic leukemia cell line

Enhancement of the cytotoxicity of cytosine arabinoside (ara-C) by granulocyte/macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF), and the mechanisms involved, were studied in the AML-193 human leukemia cell line. AML-193 cells require GM-CSF and G-CSF(CSFs) for optimum growth, and 24 h deprivation of CSFs decreased DNA synthesis measured in terms of 3H-thymidine incorporation. The DNA synthesis gradually recovered upon addition of CSFs. To examine the sensitivity to ara-C under different growth conditions, two groups of cell suspensions, one pretreated with CSFs after 24 h deprivation (CSFs(+) cells), and the other held continuously under CSFs-free conditions (CSFs(-) cells), were exposed to 1.0 microgram/ml of ara-C for 16 h. In clonogenic assays, CSFs(+) cells showed higher sensitivity to ara-C than CSFs(-) cells. These cell groups showed no significant difference in ara-C triphosphate accumulation or retention, though the amount of ara-C incorporated into the acid-insoluble fraction was two times greater in CSFs(+) cells than CSFs(-) cells, and that difference became even clearer in the retention pools. These data suggest that the enhancement of cytotoxicity by CSFs was due to the promotion of ara-C incorporation into DNA as a result of an increase of the cell fraction in the S phase.     

Expression of granulocyte-macrophage colony-stimulating factor receptors in human prostate cancer

This investigation examined the effects of NaHCO3 loading on lactate concentration ([La]), acid-base balance, and performance for a 603. 5-m sprint task. Ten greyhounds completed a NaHCO3 (300 mg/kg body weight) and control trial in a crossover design. Results are expressed as means +/- SE. Presprint differences (P < 0.05) were found for NaHCO3 vs. control, respectively, for blood pH (7.47 +/- 0.01 vs. 7.42 +/- 0.01), HCO-3 (28.4 +/- 0.4 vs. 23.5 +/- 0.3 meq/l), and base excess (5.0 +/- 0.3 vs. 0.2 +/- 0.3 meq/l). Peak blood [La] increased (P < 0.05) in NaHCO3 vs. control (20.4 +/- 1.6 vs. 16.9 +/- 1.3 mM, respectively). Relative to control, NaHCO3 produced a greater (P < 0.05) reduction in blood base excess (-18.5 +/- 1.4 vs. -14.1 +/- 0.8 meq/l) and HCO-3 (-17.4 +/- 1.2 vs. -12.8 +/- 0.7 meq/l) from presprint to postexercise. Postexercise peak muscle H+ concentration ([H+]) was higher (P < 0.05) in NaHCO3 vs. control (158.8 +/- 8.8 vs. 137.0 +/- 5.3 nM, respectively). Muscle [H+] recovery half-time (7.2 +/- 1.6 vs. 11.3 +/- 1.6 min) and time to predose values (22.2 +/- 2.4 vs. 32.9 +/- 4.0 min) were reduced (P < 0.05) in NaHCO3 vs. control, respectively. No differences were found in blood [H+] or blood [La] recovery curves or performance times. NaHCO3 increased postexercise blood [La] but did not reduce the muscle or blood acid-base disturbance associated with a 603.5-m sprint or significantly affect performance.     

Use of macrophage colony-stimulating factor in the treatment of fungal infections

Management of fungal infections is a major medical problem. The risk of developing a fungal infection is higher for patients who are undergoing dose-intensive therapy, are immunocompromised, have neutropenia, are receiving prophylactic antibiotics, have other infections, have invasive catheters, or have a history of severe trauma or burns. Survival is decreased among patients who develop fungal infection in these situations. In view of the high morbidity and mortality associated with fungal infections in transplant recipients, cytokines that enhance cell function, such as macrophage colony-stimulating factor (M-CSF), have been investigated. M-CSF enhances cytotoxicity, superoxide production, phagocytosis, chemotaxis, and secondary cytokine production in monocytes and macrophages. Animal models and clinical data suggest efficacy of M-CSF in controlling fungal infection.     

Effects of granulocyte-colony-stimulating factor and interleukin-2 on ascites formation and the survival time of nude mice bearing human ovarian cancer cells

This study assessed the effects of the Persian Gulf War on the psychological health and adjustment of military personnel in Hawaii and Pennsylvania who either deployed (N = 1,524) or did not deploy (N = 2,727) to the Persian Gulf during Operations Desert Shield/Desert Storm. All participants anonymously completed a questionnaire providing information on demographics, psychological and psychosocial health, deployment stressors, current life problems, current distress, and causal attributions of present problems. Results indicate that deployed veterans experienced significant levels of stress in-theater and continue to report significant stress in their lives today. Although considerable stress is experienced, the majority of veterans are handling it unremarkably. Implications for future deployments and the need for military-normed assessment instruments are discussed.     

Effect of angiogenesis inhibitor TNP-470 on the progression of human gastric cancer xenotransplanted into nude mice

The effect of an angiogenesis inhibitor, TNP-470, on primary tumor growth, liver metastasis and peritoneal dissemination of gastric cancer was investigated by means of an orthotopic xenotransplanted model of 2 human gastric cancers, MT-2 and MT-5. TNP-470 showed a significant inhibitory effect on the growth of primary tumors after orthotopic transplantation of both xenografts when given at a dose of 30 mg/kg on alternate days from day 7 after transplantation (early treatment). However, growth of the MT-2 primary tumor was not inhibited by administration from day 14 after transplantation (late treatment). Liver metastasis was prevented significantly by early treatment of TNP-470. In particular, early treatment of MT-2 completely inhibited the development of macroscopic foci in the liver and was significantly more effective than late treatment. Peritoneal dissemination also was inhibited. Thus, TNP-470 was revealed to have strong inhibitory activity not only on primary tumors and liver metastases but also against peritoneal dissemination. These results suggest that this agent may provide a new approach to the treatment of gastric cancer.     

Organization and histochemical phenotype of human fetal cerebellar cells following transplantation into the cerebellum of nude mice

Previous rodent studies have demonstrated the capacity of cerebellar transplants to organize into trilaminar cell layers typically observed in the normal cerebellum. In Purkinje Cell (PC)-deficient animals, PCs will migrate into the host and form synaptic connections. Recently, fetal cerebellar grafts transplanted into the Purkinje cell degeneration (pcd) mutant mouse were shown to result in an improvement of motor behaviors. These studies indicate the potential therapeutic use of neural transplantation in patients with cerebellar degeneration. In the present study, human fetal cerebellar tissue (8.5 wk postconception) was dissociated and transplanted into the normal cerebellum of nude mice. Six months following transplantation, histological analysis revealed donor cells in recipient mice. Immunostaining for the 28 kDa calcium-binding protein (calbindin) revealed the presence of donor PCs that were organized in discrete cellular layers within the transplant neuropil. In most cases the dendritic processes were oriented in a planar fashion perpendicular to the transplant cell layer. Human neurofilament immunostaining revealed bundles of donor fibers within the core of the transplant and/or at the periphery. These bundles were found to be calbindin positive (PC fibers). Three animals provided evidence of donor PC axon growth ventrally into host white matter, and in one case, this ventral migration reached the deep cerebellar nuclei. Most notable was the development of a pronounced folia-like organization by the implanted cell suspensions. Glial processes within the grafts were aligned perpendicular to the long axis of the transplant folia. These results demonstrate the capacity of human fetal cerebellar cell suspension to reorganize into cell layers typical of the normal cerebellum following transplantation into the rodent cerebellum, and develop an organotypic folia-like organization.     

Multiple factors determine the selection of the ectodomain cleavage site of human cell surface macrophage colony-stimulating factor

Human cell surface macrophage colony-stimulating factor (CSF-1256, M-CSF alpha) is converted to a soluble growth factor by a regulated proteolytic cleavage process at amino acid residues 157-159. We have previously shown that multiple factors specified by the juxtamembrane region determine the cleavage efficiency [Deng, P., Rettenmier, C. W., and Pattengale, P. K. (1996) J. Biol. Chem. 271, 16338-16343]. In the present paper, we studied the effect of various deletion, insertion, and substitution mutations at or near the cleavage site on both the number and size of cleaved CSF-1(256) products to identify the mechanisms by which the cleavage sites are selected. Deletion of regions 161-162 or 163-165, C-terminal to the cleavage site, as well as deletion of region 150-156, N-terminal to the cleavage site, each yielded a single cleavage product that was smaller than that derived from the wild type (WT). In these experiments cleavage apparently occurred at a specific distance from the transmembrane domain. Insertion of three additional residues between the normal cleavage site and the transmembrane domain yielded one major product that was the same size as the processed form of WT CSF-1(256). In this case the selection of the cleavage site was apparently determined by the amino acid sequence of the juxtamembrane region rather than by the distance from the transmembrane domain. Other amino acid substitutions at the cleavage site caused changes in cleavage site selection, providing additional evidence for the role of amino acid sequence in cleavage site selection. Finally, a comparison of cleavage site selection in the presence and absence of tunicamycin treatment showed that N-glycosylation of certain mutant forms of CSF-1(256) sterically interfered with protease accessibility, which in turn had an effect on the selection of the site used for cleavage. Taken together, these results indicate that cleavage site selection is determined by the amino acid sequence of the juxtamembrane region, the distance of the site from the transmembrane domain, and steric accessibility of the protease.     

Targeted in vivo delivery of therapeutic gene into experimental squamous cell carcinomas using anti-epidermal growth factor receptor antibody: immunogene approach

The "Fab immunogene" is a novel gene transfer vehicle in which the Fab fragment of anti-human epidermal growth factor (EGF) receptor antibody B4G7 is conjugated with poly-L-lysine to form an affinity complex with DNA. It was developed to target delivery of therapeutic genes into EGF receptor-hyperproducing tumor cells. Various characteristic features of the immunogene have been documented (Chen et al., 1998). Here we add further evidence to prove that in vitro transfer of beta-galactosidase/Fab immunogene is exclusively to EGF receptor-positive cells and that the herpes simplex virus thymidine kinase (TK)/Fab immunogene induces substantial suicide effects on A431 tumor cells when treated together with ganciclovir. The in vivo specificity of the immunogene transfer was examined using A431 tumor-bearing nude mice. When these nude mice were injected intraperitoneally with the chloramphenicol acetyltransferase (CAT)/Fab immunogene, CAT DNA was detected in the tumors as well as in liver and kidney but not brain, whereas CAT mRNA and enzyme activity were detected only in the tumors. Local and intraperitoneal injection of the TK/Fab immunogene and subsequent administration of ganciclovir effectively suppressed the growth of A431 tumors transplanted on the backs of nude mice. These observations suggest a possible application of the Fab immunogene system in cancer gene therapy.     

Addition of cisplatin improves efficacy of 131I-labeled monoclonal antibody 323/A3 in experimental human ovarian cancer

This study was conducted to determine whether the cytotoxic agent cisplatin (CDDP), also known as a radiosensitizer, can improve the efficacy of the 131I-labeled monoclonal antibody (MAb) 323/A3 in the treatment of experimental human ovarian cancer. METHODS AND MATERIALS: Nude mice bearing well-established subcutaneous FMa, OVCAR-3, or Ov.Pe xenografts were injected twice with a 2-week interval either with a bolus of CDDP, 131I-323/A3, or with a combination of both modalities. CDDP was injected at various timepoints when combined with 131I-323/A3. The efficacy of the treatment was expressed as the specific growth delay (SGD). The growth inhibitory effect of the combination was characterized to detect additivity or synergism, using the mean relative tumor volumes at 2, 4, and 6 weeks after the last injection as endpoints. RESULTS: The efficacy of 131I-323/A3 was superior to that of the maximum tolerated dose (MTD) of CDDP (6 mg/kg) in all three xenografts. The addition of CDDP to 131I-323/A3 could increase the growth inhibition in the CDDP-responsive FMa and OVCAR-3 xenografts, but not in Ov.Pe xenografts. Although this improved antitumor effect was additive rather than synergistic, the combination was more effective when compared with that of the MTD of each of the modalities alone. The time interval between the administration of a bolus injection of CDDP and 131I-323/A3 had no effect on the extent of growth inhibition in OVCAR-3 xenografts. CONCLUSION: The addition of CDDP to 131I-323/A3 resulted in an additive inhibitory effect on the growth of CDDP-responsive xenografts. As the combination of radioimmunotherapy and CDDP was more effective in the inhibition of the tumor growth when compared with that of the MTD of each of the modalities alone, this treatment may therefore be considered of use in patients with ovarian cancer responsive to CDDP.     

Inhibitory effects of ginsenoside Rh2 on tumor growth in nude mice bearing human ovarian cancer cells

Ginsenoside Rh2 (Rh2), isolated from an ethanol extract of the processed root of Panax ginseng CA Meyer, inhibits the growth of B16 melanoma cells. This study was designed to evaluate the ability of Rh2 to inhibit growth of human ovarian cancer cells (HRA) in vitro and in nude mouse. Rh2 inhibited proliferations of various established human ovarian cancer cell lines in a dose-dependent manner between 10 and 60 microM in vitro and induced apoptosis at around the IC50 dose. When HRA cells were inoculated s.c. into the right flank of nude mice, all mice formed a palpable tumor within 14 days. Although i.p. administration of Rh2 alone hardly inhibited the tumor growth, when Rh2 was combined with cis-diamminedichloroplatinum(II) (CDDP) the tumor growth was significantly inhibited, compared to treatment with CDDP alone. When mice were treated p.o. with Rh2 daily (but not weekly), the tumor growth was significantly (P<0.01) inhibited, compared to CDDP treatment alone. When Rh2 was combined with CDDP, the degree of tumor growth retardation was not potentiated. The survival time was significantly (P<0.05) longer than that of medium alone-treated controls or the group treated with CDDP alone. Then, we examined whether p.o. administration of Rh2 has a dose-dependent inhibitory effect on the tumor growth. I.p. and weekly administration of CDDP had more potent antitumor activity in the order of 1 mg/kg, 2 mg/kg and 4 mg/kg, whereas p.o. and daily administration of Rh, (0.4 to 1.6 mg/kg) not only had antitumor activity comparable to that of 4 mg/kg CDDP, but also resulted in a significant increase of the survival. Doses of Rh2 used in this study did not result in any adverse side-effects as confirmed by monitoring hematocrit values and body weight, unlike 4 mg/kg CDDP, which had severe side-effects. It is noteworthy that p.o. but not i.p. treatment with Rh2 resulted in induction of apoptotic cells in the tumor in addition to augmentation of the natural killer activity in spleen cells from tumor-hearing nude mice. Thus, particularly in view of the toxicity of CDDP, Rh2 alone would seem to warrant further evaluation for treatment of recurrent or refractory ovarian tumor.