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Hematological and biochemical profile studies help to evaluate functional changes of animals used in experiments. The aim of this study was to determine the hematological and biochemical profile of immunosuppressed BALB/c nude and C57BL/6 SCID mice after bovine ovarian xenotransplantation. Therefore, a total of 74 female mice were divided into four groups: non-xenotransplanted animals, xenotransplanted animals, xenotransplanted animals treated with eCG and xenotransplanted animals treated with FSH + LH. After anesthesia, blood samples were collected and hematologic and biochemical values were evaluated. The results showed no significant differences (p ≤ 0.05) for hematological parameters between the control group and the treatment groups of both strains. However, considering the biochemical profile, it was observed an increase of AST concentrations (p ≤ 0.05) in both strains and a decrease of ALT concentrations (p ≤ 0.05) only in C57BL/6 SCID strain of the groups subjected to hormonal treatment compared with those non subjected. Additionally, the values of the renal enzymes, urea and creatinine, did not differ (p ≤ 0.05) between the groups. Our findings suggest that the xenotransplantation procedure as well as the hormonal dosages had no significant effect on the well-being of the animals considering the evaluated hematological and biochemical profile.

WW domain-binding protein 2 (WBP2) has been demonstrated as oncogenic in breast cancer. Many studies have revealed the WBP2 gene as a high-risk gene for leukoariaosis and cerebral white matter lesions is important in the pathologic stage of glioma development. This study aimed to illustrate the underlying mechanism by which WBP2 regulates the process of glioma development. The expression pattern of WBP2 in several tumor cells was determined, clarifying the carcinogenic action of WBP2 in glioma cells. Overexpression of WBP2 in glioma cells promoted cell proliferation and migration, and the number of S-phase cells, whereas the depletion of WBP2 by RNAi-mediated knockdown restrained cell growth and cell cycle progression. Upregulation of WBP2 significantly enhanced the tumorigenic ability of U251 cells in vivo. MS/GST pulldown assay identified α-enolase (ENO1) and Homer protein homolog 3 (Homer3) as novel potent interaction partners of WBP2. Knockdown of ENO1 or Homer3 allowed cell growth and migration to return to normal levels. Furthermore, in vitro and in vivo experiments indicated that the oncogenic role of WBP2 in glioma was through modulating ENO1 and glycolysis activity via the ENO1-PI3K/Akt signaling pathway. Collectively, these results reveal that WBP2 plays a vital role in the occurrence and development of glioma, indicating a target gene for glioblastoma treatment.

Diabetes is induced in mice by using streptozotocin (STZ), a compound that has a preferential toxicity toward pancreatic β cells. We evaluated nude male mice from various sources for their sensitivity to a single high dose (160 to 240 mg/kg) of STZ. Diabetes was induced in male mice (age: median, 12 wk; interquartile range, 11 to 14 wk; body weight, about 30 g) from Taconic Farms (TAC), Jackson Laboratories (JAX), and Charles River Laboratories (CRL). Mice were monitored for 30 d for adverse side effects, blood glucose, and insulin requirements. In CRL mice given 240 mg/kg STZ, more than 95% developed diabetes within 4 to 5 d, and loss of body weight was relatively low (mean, 0.4 g). In comparison, both TAC and JAX mice were more sensitive to STZ, as evidenced by faster development of diabetes (even at a lower STZ dose), greater need for insulin after STZ, greater body weight loss (mean: TAC, 3.5 g; JAX, 3.7 g), and greater mortality. We recommend conducting exploratory safety assessments when selecting a nude mouse source, with the aim of limiting morbidity and mortality to less than 10%.

Hallmarks of malignant melanoma are its propensity to metastasize and its resistance to treatment, giving patients with advanced disease a poor prognosis. The transition of melanoma from non-invasive radial growth phase (RGP) to invasive and metastatically competent vertical growth phase (VGP) is a major step in tumor progression, yet the mechanisms governing this transformation are unknown. Matrix metalloproteinase-1 (MMP-1) is highly expressed by VGP melanomas, and is thought to contribute to melanoma progression by degrading type I collagen within the skin to facilitate melanoma invasion. Protease activated receptor-1 (PAR-1) is activated by MMP-1, and is also expressed by VGP melanomas. However, the effects of MMP-1 signaling through PAR-1 have not been examined in melanoma. Here, we demonstrate that an MMP-1/PAR-1 signaling axis exists in VGP melanoma, and is necessary for melanoma invasion. Introduction of MMP-1 into RGP melanoma cells induced gene expression associated with tumor progression and promoted invasion in vitro, and enhanced tumor growth and conferred metastatic capability in vivo. This study demonstrates that both the type I collagenase and PAR-1 activating functions of MMP-1 are required for melanoma progression, and suggests that MMP-1 may be a major contributor to the transformation of melanoma from non-invasive to malignant disease.

In this study, we addressed the hypothesis that transcriptional suppression of erythroblastosis virus E26 oncogene homolog 1 (ETS-1) is an efficient therapeutic approach to pancreatic adenocarcinoma by investigating the effect of ETS-1 suppression in human pancreatic cancer cells. We accomplished this by using an adenoviral vector encoding only the DNA-binding domain of wild-type ETS-1 (ETS-1 dominant negative, ETS-1-DN). ETS-1-DN decreases ETS-1-binding by competing for its binding to DNA. Adenoviral-mediated transfer of ETS-1-DN (adenoviral ETS-1-DN construct, AdETS-1-DN) into pancreatic tumor cell lines did not affect their proliferation rate in vitro but did significantly inhibit their in vivo growth in nude mice. Furthermore, to test the efficacy of ETS-1-DN in vivo, we injected the AdETS-1-DN into established human pancreatic adenocarcinomas grown in nude mice. This treatment significantly reduced tumor size as compared to saline injection, without any detectable side effects. Microvessel density in mouse xenografts displayed significantly lower values in tumors in which ETS-1 was downregulated. In addition, expression of the ETS-1-DN in the pancreatic cancer cells resulted in downregulation of urokinase-type plasminogen activator (u-PA) and metalloproteinase-1 (MMP-1) expression. Taken together, these data suggest that transcriptional inactivation of ETS-1 is able to significantly affect angiogenesis and growth of pancreatic cancer. This effect may be due in part to downregulation of MMP-1 and u-PA expression. Our results suggest that ETS-1-DN is a promising candidate for antiangiogenic gene therapy in pancreatic cancer.

Mutations in the winged-helix nude (whn) gene result in the nude mouse and rat phenotypes. The pleiotropic nude phenotype which affects the hair, skin, and thymus suggests that whn plays a pivotal role in the development and/or maintenance of these organs. However, little is known about whn function in these organs. We show here that in skin whn is specifically expressed in epithelial cells and not the mesenchymal cells, and using a hair reconstitution assay, we demonstrate that the abnormal nude mouse hair development is attributable to a functional defect of the epithelial cells. Examination of nude mouse primary keratinocytes in culture revealed that these cells have an increased propensity to differentiate in an abnormal fashion, even under conditions that promote proliferation. Furthermore, nude mouse keratinocytes displayed a 100-fold increased sensitivity to the growth-inhibitory/differentiation effects of the phorbol ester TPA. In parallel with these findings, we directly show that whn functions as a transcription factor that can specifically suppress expression of differentiation/TPA-responsive genes. The region of Whn responsible for these effects was mapped to the carboxy-terminal transactivating domain. These results establish whn as a key regulatory factor involved in maintaining the balance between keratinocyte growth and differentiation. The general implications of these findings for an epithelial self-renewal model will be discussed.

The pharmacokinetics of a disulfide linked conjugate of a murine monoclonal antibody A7 with neocarzinostatin (A7-NCS) was studied following its intravenous administration to nude mice. Disappearance of the conjugate from the circulation was biphasic: an early rapid phase was followed by a much slower phase. The conjugate was removed from the blood circulation with a half-life of 12 hr, showing nearly the same kinetics as the free antibody. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the disulfide linkage in A7-NCS was stable at least for 48 hr after administration of the conjugate to nude mice. The conjugate concentration in a human colon cancer SW1116 derived tumor reached maximum at 24 hr after injection and remained high for an additional 24 hr. The passive hemagglutination inhibition assay revealed that NCS in the conjugated form can be efficiently delivered to the target tissue. The present report indicates that A7-NCS was sufficiently stable in circulation to reach the target tumor without releasing NCS.

Products from the hydrolysis of phosphatidylinositol 4,5-bisphosphate (IP3) can increase and/or potentiate cAMP accumulation in a variety of cells. Antibody to surface immunoglobulins activates IP3 hydrolysis in B-lymphocytes. In this study we have examined whether anti-Ig also stimulated and/or potentiated increases in the cAMP levels of splenocytes from athymic nude mice. Furthermore, since TPA potentiates anti-Ig-induced DNA synthesis and cAMP modulates DNA synthesis, the effects of TPA on any anti-Ig-induced changes in cAMP were also studied. Antibody (25 micrograms/ml) stimulated a rapid ris in cAMP which increased from 250 fmol/10(6) cells to 400 fmol/10(6) cells within 1 min and then subsided to 310 fmol/10(6) cells by 10 min. TPA (96 nM) suppressed the anti-Ig-induced cAMP accumulation at 1 min by 60%, but potentiated the forskolin (114 microM)-induced rise by 151%. Two other activators of protein kinase C, dioctanoylglycerol (5 microM), and anti-Ig (25 micrograms/ml), also potentiated the forskolin response by 198% and 52%, respectively. These results suggest that modulation of the adenylate cyclase system by anti-Ig may act in concert with cytokines and/or prostaglandins secreted by other lymphoid cells to define the state of proliferation or differentiation in B-cells.

We propose that hyaluronate, a major component of extracellular matrices through which cells migrate during embryonic tissue development and in regenerative processes, is also concentrated in the environment through which neoplastic cells invade local host tissues and may facilitate this process. The hyaluronate content of invasive V2 carcinoma grown in rabbit was found to be 3-4 times greater than that of the same tumor grown in the nude mouse, in which it is noninvasive. Moreover, hyaluronate concentrations were most elevated in the connective tissue interface between the tumor mass and the neighboring host tissue in the invasive rabbit tumors. The particular site of tumor implantation in the rabbit or nude mouse did not affect the concentrations of hyaluronate in either the parenchyma or the surrounding connective tissue. Similar values were obtained for neoplasms grown in muscle, which normally contains little hyaluronate, and in subcutaneous tissue, which is relatively rich in this glycosaminoglycan.

Thymosin beta 4, recently isolated from calf thymus, is present in a number of rat and mouse tissues, including spleen, thymus, brain, lung, liver, and heart muscle. High concentrations are found in peritoneal macrophages, suggesting that its occurrence in other tissues may be related to the presence of macrophages or macrophage-like cells in these tissues. The conclusion that "thymosin" beta 4 does not originate solely in the thymus gland is supported by the high concentrations found in tissues of athymic (nu/nu) mice.

The biodistribution of yttrium- and indium-labeled monoclonal antibody (MAb) B72.3 IgG using three different chelate conjugates (SCN-Bz-EDTA, CA-DTPA, and SCN-Bz-DTPA) was compared in athymic mice bearing LS-174T tumors. The 88Y-SCN-Bz-DTPA-B72.3 yielded 40% ID/g at 5-7 days in the tumors, while the 88Y-SCN-Bz-EDTA-B72.3 and 88Y-CA-DTPA-B72.3 showed only 6-8% ID/g. The yttrium uptake in the bone with the SCN-Bz-EDTA and CA-DTPA conjugated IgG was over 14 and 11% ID/g, respectively, while 88Y-SCN-Bz-DTPA-B72.3 showed only 3% ID/g. In contrast, the 111In-labeled B72.3 uptake in the bone with all three chelate conjugates was 2-3% ID/g. The differences in yttrium- versus indium-labeled MAb biodistributions demonstrate the difficulty in using 111In-labeled MAbs to predict the biodistribution and dosimetry of 90Y-labeled MAbs unless chelate conjugates such as SCN-Bz-DTPA are used.

Hairless mice were fed with 8-methoxypsoralen by gastric tube and exposed to UVA light to produce threshold phototoxic reactions. 3H-thymidine autoradiography revealed no significant difference of the epidermal labelling index as compared to that of nonirradiated animals (4.8 vs 6.2). Single PUVA exposures performed 2,8,14 and 24 hr after tape stripping lead to suppression of a wave of synchronized DNA synthesis present in nonirradiated control animals. These data demonstrate different reactions of stripped and unstripped epidermis to PUVA exposures and offer indirect evidence for the suppression of DNA synthesis in hyperproliferative skin disorders by PUVA in vivo.

Nude mice each attached to a respirator to avoid pulmonary uptake were exposed in a glass exposure chamber to 200, 1000 or 3000 ppm of benzene, toluene or tetrachloroethylene (perclene) for 2, 4 or 6 h. The animals were killed at the end of the study and the amount of each solvent retained in the whole body was determined by gas chromatography. Skin absorption rates were calculated from the amount retained in the whole body using the single compartment model (elimination rate constant) obtained in a previous experiment. There was a linear relationship between the amount of skin absorption and exposure time, and also a linear relationship between the skin adsorption rate and concentration of exposed vapors. Skin absorption of solvent vapors occurs by passive diffusion as defined by Fick's law. The skin absorption coefficient (cm/h) of each solvent vapor was calculated by dividing the skin absorption rate by exposure concentration; the values were 1.24 for toluene, 1.00 for perclene and 0.619 for benzene. The coefficient may be useful for evaluating the amount of skin absorption (ng) was calculated by multiplying the skin absorption coefficient (cm/h), concentration of solvent vapor (ng/cm3), exposure time (h) and exposed skin area (cm2).

A human mucinous cystadenocarcinoma of the ovary was propagated in nude mice. After cryopreservation of the 3rd-passage xenograft for 4 years, subsequent in vivo transplants showed the emergence of two distinct populations, one resembling the original human adenocarcinoma and the other resembling a spindle-cell sarcoma. These two tumor cell populations were confirmed to be human and murine, respectively, by cytogenetic study, and the epithelial tumor cells were further shown to be of human origin by immunoperoxidase staining of blood group A antigen. Separation of the two tumor cell populations in vitro permitted the independent propagation of the human and murine tumor cells in vitro and in vivo. The murine sarcoma was also capable of growth in ordinary BALB/c mice. These results indicate that human cancer cells can induce malignancy in adjacent, putatively normal, cells of nude mice in vivo.

Terminal deoxynucleotidyl transferase (TdT) expression in bovine serum albumin (BSA) gradient-fractionated bone marrow cells was examined in NIH Swiss nu/nu and thymectomized C57BL/6 mice. In nude mice, TdT levels were approximately 10% of those of thymus-bearing littermates. In C57BL/6 mice, thymectomy caused a time-dependent loss of TdT activity in bone marrow cells. To determine whether or not not the apparent thymic requirement for TdT expression in bone marrow was mediated by thymic hormones, we examined the effects of thymosin fraction 5. Treatment of either NIH Swiss nu/nu or thymectomized C57BL/6 mice with thymosin fraction 5 restored the levels of TdT activity in BSA gradient-fractionated bone marrow cells to normal. Moreover, treatment of BSA gradient-fractionated bone marrow cells from NIH Swiss nu/nu or thymectomized C57BL/6 mice in tissue culture with thymosin fraction 5 induced TdT expression. In tissue culture, TdT induction was optimal with 25 ng/ml of thymosin fraction 5, it occurred within 6 h, and it was completely inhibited by actinomycin D. The effect was specific in that neither control nor spleen fraction 5-treated cells were induced to express TdT. These data demonstrate that TdT expression in bone marrow cells is under the direct control of thymic polypeptide hormones.