Calcitriol enhancement of TPA-induced tumorigenic transformation is mediated through vitamin D receptor-dependent and -independent pathways

We previously showed that 1alpha,25-dihydroxyvitamin D3, calcitriol, enhanced phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) induced tumorigenic transformation of mouse epidermal JB6 Cl41.5a cells. To determine if calcitriol regulates this enhancement through a nuclear vitamin D receptor (VDR)-dependent or -independent pathway, we used vitamin D analogs which induce biological responses by either of these mechanisms. In JB6 Cl41.5a cells, 1alpha,24-dihydroxy-22-ene-24-cyclopropyl-vitamin D3 (BT), which like calcitriol binds to VDR and regulates transcription, inhibited cell growth, stimulated expression of nonphosphorylated osteopontin (OPN), and enhanced TPA-induced anchorage-independent growth (AIG, an in vitro assay which highly correlates with tumorigenicity of these cells). 25-Hydroxy-16-ene-23-yne-vitamin D3 (AT), which stimulates calcium influx but has low affinity for VDR, had moderate effects on cell growth and expression of OPN. However, it enhanced TPA-induced tumorigenic transformation, though to a lesser extent than BT, thus suggesting that a VDR-independent mechanism is involved. Since 1alpha-hydroxylase activity was detected in JB6 cells, AT could be converted into 1alpha,25-dihydroxy-16-ene-23-yne-vitamin D3 (V), an analog which binds with high affinity to VDR, and could subsequently enhance TPA-induced AIG. To verify whether the VDR-independent pathway is involved in calcitriol enhancement of tumorigenic transformation, two additional VDR-independent analogs, 1alpha,25-dihydroxy-lumisterol3 (JN) and 24R,25-dihydroxyvitamin D3 (AS), were tested. The analog JN, which stimulates calcium transport and cannot be further hydroxylated at 1-carbon position, increased TPA-induced AIG, while AS, which inhibits calcium influx, did not. These studies suggest that a VDR-independent pathway, perhaps stimulation of calcium influx, and a VDR-dependent mechanism, which directly affects transcription, are involved in calcitriol's enhancement of TPA-induced tumorigenic transformation in JB6 Cl41.5a cells.

Gene therapy for murine mucopolysaccharidosis type VII

Mucopolysaccharidosis type VII (MPS VII) is caused by a deficiency in the lysosomal enzyme beta-glucuronidase resulting in the accumulation of undegraded glycosaminoglycans in many tissues. A murine model of MPS VII shares many of the clinical, biochemical and histopathological features of human MPS VII and has provided an opportunity to study novel therapeutic approaches in a system with a uniform genetic background. Retroviral mediated gene therapy directed to the hematopoietic system or to artificial neo-organs resulted in low levels of enzyme in several tissues and reduced lysosomal storage in the liver and spleen. Partial correction of the disease in the eye was observed following an intravitreal injection of recombinant adenovirus. Neither retroviral nor adenoviral mediated gene transfer techniques resulted in a systemic reduction of lysosomal storage. Here we discuss several novel gene transfer approaches designed to increase the systemic levels of beta-glucuronidase in the MPS VII mouse.

Diuretic renography findings in enterovesical fistula

A 73-year-old male presented with a 2 week history of gross haematuria and faecal material in the urine. Bone scan for cancer work-up showed 99T(cm)-MDP radioactivity accumulation in the transverse and descending colon. A 99T(cm)-DTPA diuretic renogram was arranged to study renal function and to determine the location of the enterovesical fistula. Diuretic renography demonstrated extraurinary tract radioactivity in the sigmoid colon in the early images, extending to the descending and transverse colon in the subsequent dynamic images. A sigmoid colon adenocarcinoma with bladder wall invasion and fistula formation was confirmed at surgical operation. The impressive dynamic diuretic renography study in this patient was helpful in determining the location of the fistula and in planning surgical management.

Diagnosis of prostate cancer: comparison of serum prostate specific antigen, digital rectal examination and transrectal ultrasonography

BACKGROUND

While prostate specific antigen (PSA) is useful as a tumor marker for monitoring patients with prostate cancer after definitive therapy, limitations have been noted when it is used for early detection of prostate cancer.

METHODS

We reviewed the charts of 121 patients who had undergone prostate needle biopsies, documented digital rectal examination (DRE) and serum PSA determination before biopsy from January 1993 to October 1994. Indications for biopsy included abnormal DRE. PSA level greater than 4.0 ng/ml or abnormal lesions on transrectal ultrasonography (TRUS).

RESULTS

Seventeen patients (14%) had stage A carcinoma with normal DRE and PSA levels from 0.1 to 34.9 ng/ml (mean 9.0 ng/ml). Four patients (3%) had stage B carcinoma with an average PSA level of 32.3 ng/ml and less than one lobe indurated on DRE. Six patients (5%) had stage C carcinoma and had an average PSA level of 48.5 ng/ml and less than one lobe indurated on DRE. Ninety-four (78%) patients had stage D carcinoma with an average PSA level of 120 ng/ml and more than one lobe indurated on DRE. While hypoechoic sectors were more than twice as likely as isoechoic sectors of the prostate to contain malignancy on biopsy, nearly 20% of cancers were found in isoechoic sectors.

CONCLUSION

Serum PSA is the most accurate of the three diagnostic tests evaluated. The addition of DRE or TRUS improves the detection rate of prostate cancer over PSA alone.

Use of the transurethral prostatectomy clinical path to monitor health outcomes

PURPOSE

We evaluated the effect on cost and medical care quality of use of the transurethral prostatectomy clinical path.

MATERIALS AND METHODS

Results in 100 patients treated when the transurethral prostatectomy clinical path was used were compared to those of 100 treated by the same physicians before implementation of this path.

RESULTS

After implementation of the transurethral prostatectomy clinical path the length of hospital stay was significantly decreased from 5.9 to 5.0 days (p < 0.01) and Foley catheterization time was significantly decreased from 3.13 to 2.84 days (p < 0.01). Antibiotics were routinely used from the day before surgery to the day of hospital discharge as required by patient conditions. Therefore, a shorter hospital stay will significantly decrease the use of antibiotics. After implementation of the clinical path the average admission charges were decreased significantly by 17% (p < 0.01). Although some results from use of this path will not significantly affect costs, they will reflect some quality improvement. The effect of clinical path implementation on length of hospital stay between patients treated by junior and senior attending physicians was not significant. However, there was a statistically significant difference (p < 0.01) between results obtained by junior and senior attending physicians regarding average admission charges.

CONCLUSIONS

Implementation of the transurethral prostatectomy clinical path can improve health care outcome by decreasing length of stay and admission charges, and improving quality of medical care, particularly for patients treated by junior attending physicians.

Regulation of rat granulosa cell alpha-inhibin expression by luteinizing hormone, estradiol, and progesterone

OBJECTIVE

Our purpose was to assess the effects of follicle-stimulating hormone, luteinizing hormone, forskolin (an adenylyl cyclase activator), estradiol, and progesterone on alpha-inhibin promoter activity in an in vitro fusion gene-transfection system.

STUDY DESIGN

A fusion gene consisting of the alpha-inhibin 5' flanking and promoter regions linked to the chloramphenicol acetyl transferase reporter gene was constructed. A granulosa cell line originally derived from an inbred strain of Berlin Duckrey rats was transiently transfected with the fusion gene. Fusion gene activity was determined by measuring chloramphenicol acetyl transferase activity in transfected cells.

RESULTS

Both follicle-stimulating hormone and luteinizing hormone activated the alpha-inhibin promoter. Activity in response to combined luteinizing hormone-forskolin treatment was greater than the summation of the activities of the two treatments individually, suggesting that the effects of luteinizing hormone might be partially mediated by second messengers other than cyclic adenosine monophosphate. Gonadotropin-stimulated activity was diminished by estradiol and combined estradiol-progesterone treatments.

CONCLUSIONS

The stimulatory effects of follicle-stimulating hormone and luteinizing hormone on alpha-inhibin production are mediated at least in part by stimulation of the alpha-inhibin promoter. The stimulatory effects are blunted by estradiol-progesterone. These observations may partially explain how alpha-inhibin is down-regulated in vivo in response to the preovulatory luteinizing hormone surge.

Delivery of human factor IX in mice by encapsulated recombinant myoblasts: a novel approach towards allogeneic gene therapy of hemophilia B

A potentially cost-effective strategy for gene therapy of hemophilia B is to create universal factor IX-secreting cell lines suitable for implantation into different patients. To avoid graft rejection, the implanted cells are enclosed in alginate-polylysine-alginate microcapsules that are permeable to factor IX diffusion, but impermeable to the hosts' immune mediators. This nonautologous approach was assessed by implanting encapsulated mouse myoblasts secreting human factor IX into allogeneic mice. Human factor IX was detected in the mouse plasma for up to 14 days maximally at approximately 4 ng/mL. Antibodies to human factor IX were detected after 3 weeks at escalating levels, which were sustained throughout the entire experiment (213 days). The antibodies accelerated the clearance of human factor IX from the circulation of the implanted mice and inhibited the detection of human factor IX in the mice plasma in vitro. The encapsulated myoblasts retrieved periodically from the implanted mice up to 213 days postimplantation were viable and continued to secrete human factor IX ex vivo at undiminished rates, hence suggesting continued factor IX gene expression in vivo. Thus, this allogeneic gene therapy strategy represents a potentially feasible alternative to autologous approaches for the treatment of hemophilia B.

Microencapsulation--an alternative approach to gene therapy

Non-autologous somatic gene therapy' is a novel approach to gene therapy which does not depend on genetic modification of the patient's own cells. Recombinant cell lines secreting a desired therapeutic gene product can be implanted into different patients requiring the same product replacement. Graft rejection is avoided by enclosing these cells in immuno-isolation devices whose permeability excludes the host's immune mediators but permits the transit of nutrients and recombinant gene products. The feasibility of this strategy is demonstrated by expression of recombinant human enzymes, hormones and coagulation factors from fibroblasts or myoblasts enclosed within alginate-poly-L-lysine-alginate microcapsules. Its clinical efficacy is demonstrated by the correction of pathological phenotypes in murine models of human endocrine and lysosomal storage diseases. Hence, this approach may lead to a potentially cost-effective method of gene-based therapy.

Growth retardation--an unexpected outcome from growth hormone gene therapy in normal mice with microencapsulated myoblasts

Recently, we have succeeded in using nonautologous myoblasts engineered to secrete mouse growth hormone (GH) to correct partially the growth retardation of the Snell dwarf mice, which suffer from pituitary GH deficiency. The allogeneic myoblasts were protected from immune rejection by enclosure in permselective microcapsules fabricated from alginate, thus validating the clinical efficacy of using universal nonautologous cells for somatic gene therapy. Because GH therapy is considered also for treating patients with normal pituitary function, we now apply this protocol to treat normal mice to evaluate the potential consequences of using GH gene therapy in subjects with no demonstrated GH deficiency. When microencapsulated allogeneic myoblasts engineered to secrete mouse GH were implanted into normal male and female mice, contrary to expectation, the treated animals became significantly shorter and lost weight; their internal organs became smaller and their tibial growth plates were less differentiated, indicating reduced skeletal growth. Females were more severely affected than males and 2 animals died by day 13 of unknown cause. By day 70, most of the abnormalities were restored to normal except for body weights, which remained below normal. In conclusion, although somatic gene therapy for GH delivery is beneficial for pituitary dwarfism, it may have adverse metabolic consequences in those with normal hypothalamic-pituitary functions, and the female mice were more severely affected than males.

Effects of a medical expert system on differential diagnosis of renal masses: a prospective study

A medical expert system, RMDS, was used to prospectively evaluate patients undergoing nephrectomy for suspected renal masses. The effects of a medical expert system on differential diagnosis of renal masses were investigated. After RMDS consultation, three chief residents and one junior attending physician changed their preoperative diagnosis and significantly increased their diagnostic accuracy. The results indicate that the medical expert system may have an useful role in preoperative diagnosis of renal masses.

Correction of the growth defect in dwarf mice with nonautologous microencapsulated myoblasts--an alternate approach to somatic gene therapy

Most of the currently approved human gene therapy protocols depend on genetic modification of autologous cells. We propose an alternate and potentially more cost-effective approach by implanting genetically modified "universal" cell lines to deliver desired gene products to nonautologous recipients. The recombinant allogeneic cells are protected from rejection after implantation by enclosure within immuno-protective alginate-poly-L-lysine-alginate microcapsules. The clinical efficacy of this strategy is now demonstrated by implanting microencapsulated allogeneic myoblasts engineered to secrete mouse growth hormone into the growth hormone-deficient Snell dwarf mice. The treated mutants attained increases in linear growth, body weights, peripheral organ weights, and tibial growth plate thickness significantly greater than those of the untreated controls. Secondary response to the exogenous growth hormone stimulation also resulted in increased fatty acid metabolism during the first month post-implantation. The microcapsules retrieved after about 6 months of implantation appeared intact. The encapsulated myoblasts retained a viability of > 60% and continued to secrete mouse growth hormone. Thus, implantation of nonautologous recombinant cells corrected partially the pleiomorphic effects of a transcription factor mutation in the Snell dwarf mice and the encapsulated cells remained functional for at least 6 months. This simple method of delivery recombinant gene products in vivo is a benign procedure, obviates the need for patient-specific genetic modification, and is amenable to industrial-scale quality control. It should have wide applications in therapies requiring a systemic continuous supply of recombinant gene products.

Delivery of a secretable adenosine deaminase through microcapsules--a novel approach to somatic gene therapy

Many current gene therapy protocols require genetic modification of autologous cells. An alternate approach is to use universal recombinant cell lines engineered to secrete in vivo the desired gene products. Enclosing these cells within immunoprotective devices before implantation would prevent rejection of the nonautologous donor cells. To overcome the limitation that not all therapeutic gene products are secreted, we now propose to fuse a signal sequence to the amino terminus of a nonsecreted protein such as human adenosine deaminase (ADA), thus directing the product into a secretory pathway for release from the cells. A fusion gene constructed between the cDNA of the beta-lactamase signal sequence and human ADA expressed a product after in vitro transcription and translation that was immunologically similar to the human protein. Mouse fibroblasts transfected with the fusion gene demonstrated secreted ADA activity that resembled the human cytosolic enzyme in its heat stability, pH optimum, KM, electrophoretic mobility, and immunologic reactivity. Hence, the secreted enzyme expressed from the fusion gene is antigenically and enzymatically similar to the authentic human form. When transfected mouse fibroblasts or myoblasts were enclosed in permselective alginate-poly-L-lysine alginate microcapsules, ADA activity was secreted from the microcapsules and the cells remained viable for over 5 months. Hence, a secretable and functional human ADA has been constructed that can be delivered from recombinant cells within immunoprotective capsules. The success of this strategy provides the prototype for engineering nonsecreted gene products for therapy via this novel method of somatic gene therapy.

Behavioral consequences of bone marrow transplantation in the treatment of murine mucopolysaccharidosis type VII

The gusmps/gusmps mouse is a model of the human lysosomal storage disease mucopolysaccharidosis type VII caused by deficient beta-glucuronidase activity. Bone marrow transplantation has been shown to correct some of their biochemical and pathological abnormalities but its efficacy in correcting their neurological functional deficits is unknown. We transplanted the neonatal gusmps/gusmps mice and their normal controls and evaluated their central nervous system function with two behavioral tests: the grooming test, a developmentally regulated and genetically based activity, and a Morris water maze test which assessed spatial learning abilities. The two transplanted groups groomed less than the normals, were unable to remember the location of an invisible platform from day to day, and were severely impaired at developing strategies to locate the platform in unfamiliar locations. The performance of both normal and mutant transplanted groups was clearly inferior to the untreated normals and, in some instances, close to or worse than the untreated mutants, even though the enzyme abnormalities of the mutants have been partially corrected. Hence, the behavioral deficits in the mutant mice were not restored to normal while similarly treated normal mice showed significant functional deterioration, indicating the detrimental consequence of this therapy in the neonatal period.

Calcitriol regulation of osteopontin expression in mouse epidermal cells

We previously showed that calcitriol (1 alpha,25-dihydroxyvitamin D3) induces clonal mouse epidermal JB6 Cl41.5a cells to synthesize and secrete a nonphosphorylated form of osteopontin (OPN) in a dose-dependent and metabolite-specific manner. To investigate whether OPN expression is transcriptionally regulated by calcitriol in these cells, we first determined the early time course of calcitriol-induced expression of OPN protein and steady state levels of OPN messenger RNA (mRNA). Calcitriol treatment of JB6 Cl41.5a cells for 6 h caused increased secretion of [35S]methionine-labeled OPN, with maximal levels attained after 8 h of treatment. Northern analyses showed that steady state levels of OPN mRNA increase before the synthesis and secretion of OPN protein. Treatment of JB6 Cl41.5a cells with calcitriol and the transcriptional inhibitor actinomycin-D (2-250 ng/ml) indicated that calcitriol-induced accumulation of steady state OPN mRNA and secretion of OPN protein were dose dependently inhibited by actinomycin-D. These data suggest that calcitriol regulates the expression of OPN at the level of transcription. Furthermore, calcitriol increased the steady state level of OPN mRNA in a dose-dependent manner. Calcitriol-mediated increases in OPN expression were also observed in a transfection assay using a construct consisting of a portion of the promoter region of the OPN gene fused to the luciferase reporter gene. In addition, a study using 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole, an adenosine analog that inhibits mRNA synthesis, showed that calcitriol treatment did not significantly increase the stability of OPN mRNA. These findings suggest that calcitriol increases the expression of OPN mRNA and protein by stimulating transcription.

Clinical evaluation of a renal mass diagnostic expert system

In this paper, we describe our clinical evaluation of the diagnostic accuracy of the renal mass diagnostic system (RMDS) and of seven physicians. To investigate the value of intravenous urography (IVU) and/or retrograde urography (RU) in diagnosing renal parenchymal tumors and tumors of the renal pelvis, RMDS and the seven physicians were tested with and without the information regarding IVU/RU at two different times. From this study we believe that RMDS can help residents in making more accurate presurgical renal mass diagnosis, and may eliminate the need for IVU/RU in the diagnosing process for a specific group of patients.

Calcium-binding properties of osteopontin derived from non-osteogenic sources

Osteopontin (OP), purified from rat bone, binds Ca2+ but whether different molecular forms of OPs derived from non-osteogenic sources and non-phosphorylated OP also possess this property remains to be determined. Furthermore, it is not known which specific site or sites of the molecule bind Ca2+. In the present study, following an established procedure, total proteins in the conditioned media from OP-synthesizing cell cultures were separated by SDS-PAGE, transferred to Immobilon-P membranes, and incubated with 45CaCl2, then Ca2+ ions bound to protein bands were analyzed by autoradiography. Purified OPs, and synthetic oligopeptides representing specific domains of the OP molecule were adsorbed on the membrane and processed as described above. Our results show that OPs synthesized by normal rat kidney cells, oncogenically transformed Rat-1 cells, OP purified from human milk, and non-phosphorylated OP secreted by 1 alpha, 25-dihydroxyvitamin D3-treated mouse epidermal JB6 cells all bind detectable levels of Ca2+ with specificity. We also show that a synthetic peptide representing the domain of OP which contains nine consecutive aspartic acid residues binds Ca2+ with specificity. It is probable, therefore, that a Ca(2+)-binding site resides in this region of the OP molecule. We conclude that Ca(2+)-binding is a general property of OP, irrespective of its molecular mass and origin, and the phosphate moieties of OP may not influence the conformation or accessibility of the Ca2+ affinity sites of the molecule.

Using ILIAD system shell to create an expert system for differential diagnosis of renal masses

Differential diagnosis of renal masses is an important and difficult process. A renal mass diagnostic system (RMDS) developed by using the ILIAD expert system shell has been created for diagnostic consultations and patient simulations. Seventy-two cases of renal mass have been tested on this system and the diagnostic accuracy was compared to that of residents. The overall diagnostic accuracy (75%) for renal masses is significantly better than second-year urological residents (60%) and not worse than urological chief residents (71%). The expert system also displays the cost of the diagnostic procedures so that the user can choose the most cost-effective diagnostic process. We conclude that this powerful renal mass diagnosis system developed by using ILIAD system shell can be used as a teaching, self-training and clinical tool for urological residents.

Immunological status and pathology of coxsackie B viral myocarditis and dilated cardiomyopathy

The changes in 15 cases of viral myocarditis and 28 cases of dilated cardiomyopathy were reported and compared, which were the pathological changes of endomyocardial biopsy; NK cells activity; % of peripheral T lymphocytes and its subsets determined by using OKT3,4,8 (OKT3-peripheral total lymphocytes; OKT4-helper cells; OKT8-suppressive cells) monoclonal antibody; values of immunoglobulin IgG, IgA, IgM; titer of coxsackie B antibody neutralization test. And a discussion on their relationship was included.

Delivery of recombinant gene products with microencapsulated cells in vivo

If established cultured cell lines genetically modified to secrete desired gene products could be implanted in different allogeneic recipients without immune rejection, novel gene products would be delivered more cost effectively. We tested this strategy by encapsulating mouse Ltk- cells transfected with the human growth hormone (hGH) gene in immunoprotective perm-selective alginate microcapsules. Allogeneic mice implanted with these microcapsules demonstrated hGH in their circulation (0.1-1.5 ng/ml serum) within the first 2 weeks. Control mice implanted with only the transfected cells without microcapsules did not demonstrate significant levels of circulating hGH. By about 3 weeks, antibodies against hGH developed in the microcapsule-implanted mice. The immune response was detected only against the hGH and no other secretory products from the transfected cells. The antibody titer continued to escalate for more than three months, thus demonstrating indirectly the continued delivery of the growth hormone. The persistent expression of the transgene and survival of the transfected cells were verified when the microcapsules were retrieved periodically to demonstrate that the encapsulated cells remained viable, proliferative, and productive of hGH even by 78-111 days. In conclusion, delivering gene products with genetically modified allogeneic cells in vivo has been shown feasible for prolonged periods. This technology should have potential applications in somatic gene therapy and in treatment of other somatic diseases.

Metachromatic leukodystrophy: multiple nonfunctional and pseudodeficiency alleles in a pedigree: problems with diagnosis and counseling

Metachromatic leukodystrophy is due to deficient activity of arylsulfatase A, an enzyme important in myelin catabolism. The deficiency can be caused by different point mutations in the gene coding for arylsulfatase A (nonfunctional alleles). In addition, certain mutations result in low levels of enzyme activity detectable with artificial substrates in vitro but no clinical dysfunction (pseudodeficiency alleles). The described family has various combinations of normal, nonfunctional, and pseudodeficiency alleles that presented diagnostic and counseling dilemmas which were resolved at the genomic level. We find no evidence that compound heterozygote individuals have subclinical involvement of the nervous system. We report the clinical, pathological, electrophysiological, imaging, biochemical, and genetic data of this family and discuss the difficulties in analyzing such pedigrees.

Expression of human factor IX by microencapsulated recombinant fibroblasts

Deficiency of clotting factor IX (FIX) causes hemophilia B in humans. We propose a novel approach to its treatment by engineering FIX-secreting cell lines suitable for implantation in different allogeneic hosts. To prevent graft rejection following implantation, the recombinant cells can be protected with biocompatible membranes that permit exit of FIX but not entry of cellular immune mediators. To explore the feasibility of this approach, we now report on the creation of mouse Ltk- fibroblast cell lines that can deliver FIX through such immune-protective membranes. Mouse fibroblasts (Ltk-) were transfected with the cDNA for human FIX and clones secreting high levels of FIX were isolated. About 70% of the secreted FIX was biologically active. Over 98% of the recovered biological activity was precipitable by barium citrate, indicating appropriate. gamma-carboxylation of the secreted FIX. The secreted FIX was similar in molecular weight and immunoreactivity to plasma-derived human FIX. Upon enclosure in microcapsules fabricated from the biocompatible polymers, alginate-polylysine-alginate, the cells survived the encapsulation procedure with about 70-90% viability, proliferated within the microcapsules to twice their original number within 2 weeks, and continued to secrete FIX into the culture medium at similar rates as the unencapsulated cells. The biological activity, degree of post-translational gamma-carboxylation, and immunoreactivity of the FIX recovered from the culture media of the encapsulated cells were identical to those of the FIX secreted by the unencapsulated cells. In conclusion, fibroblasts engineered to secrete recombinant human FIX can proliferate and continue to secrete biologically active FIX through the alginate microcapsules. This demonstrates the feasibility of using microencapsulated recombinant cells to deliver human FIX and the potential for allogeneic somatic gene therapy for hemophilia B.

1 alpha,25-Dihydroxyvitamin D3 enhances 12-O-tetradecanoylphorbol-13-acetate- induced tumorigenic transformation and osteopontin expression in mouse JB6 epidermal cells

To study the role of 1 alpha,25-dihydroxyvitamin D3 (calcitriol) in tumor promotion, we used JB6 C141.5a cells, a mouse epidermal cell model of tumor promotion. The phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) irreversibly induces anchorage-independent growth and tumorigenicity in these cells. Since we previously showed that calcitriol does not transform these cells but inhibits their proliferation, we hypothesized that calcitriol would inhibit TPA-induced transformation. Concurrent treatment of JB6 C141.5a cells with TPA and calcitriol revealed that calcitriol enhanced (1.7- to 10-fold, depending on dose) TPA-induced anchorage-independent growth without enhancing cell proliferation. Furthermore, a more than additive effect on osteopontin mRNA and protein levels was observed with concurrent drug treatment, which yielded a more highly phosphorylated form of osteopontin. These studies suggest coordinate regulation between the signaling pathways for calcitriol and TPA in JB6 C141.5a cells and further implicate expression of phosphorylated osteopontin in tumorigenesis.

Behavioural abnormalities in a murine model of a human lysosomal storage disease

The gusmps/gusmps mouse is a model of the human lysosomal storage disease mucopolysaccharidosis type VII due to deficient beta-glucuronidase activity. We now report behavioural abnormalities associated with this single gene defect. In grooming, a developmentally regulated and genetically based activity, the mutant mice spent 1-5% of the normal time for body grooming and about 60% of the normal time in face grooming when stimulated with a light water mist. In the Morris water maze which tests spatial learning, the mutants could learn to locate an invisible platform but were deficient in remembering its location the next day or developing strategies to locate it in new positions. Thus, the gusmps/gusmps mouse demonstrates behavioural, memory and cognitive deficiencies suitable for monitoring functional restorations in therapy.