Cytokine gene therapy for myocarditis by in vivo electroporation

Cytokines are important pathophysiologic and pathogenic factors in cardiovascular disorders, including viral myocarditis. We attempted to treat viral myocarditis with cytokine gene therapy by transferring an inhibitory cytokine, IL-1 receptor antagonist (IL-1ra) or viral IL-10 (vIL-10), by in vivo electroporation, a new method for gene transfer into muscle. Four-week-old male DBA/2 mice were inoculated intraperitoneally with 10 PFU of encephalomyocarditis virus. Immediately after virus inoculation, an expression plasmid carrying IL-1ra or vIL-10 was injected into tibialis anterior muscles followed by electroporation. Serum levels of IL1ra and vIL-10 reached 10.5 and 2.3 ng/ml, respectively, on day 5, when gene expression reached its peak. Histopathological examination showed that myocardial cellular infiltration was improved in mice treated with IL-1ra or vIL-10 compared with the control group. On day 14 after the onset of myocarditis, transfer of IL1ra or vIL-10 expression plasmid had significantly improved the survival rates of the animals. The expression of TNF-alpha was decreased to 0.60-fold (p < 0.005) and inducible nitric oxide synthase (iNOS) 0.43-fold (p < 0.005) by IL-1ra treatment, and the expression of IFN-gamma in the heart was decreased to 0.35-fold (p < 0.05), and iNOS 0.21-fold (p < 0.005), by vIL-10 relative to the controls. These results show that gene therapy with IL-1ra or vIL-10 expression plasmid was effective in the treatment of viral myocarditis, and in vivo electroporation may be a useful method by which to deliver cytokine therapy in cardiovascular diseases.

Bone resorption associated with uncoupling of osteoclastic and osteoblastic activities in adult T cell leukemia with hypercalcemia: case report

A 64-year-old woman with adult T cell leukemia (ATL) was admitted to our hospital with severe hypercalcemia. The serum calcium level was elevated to 14.9 mg/dl. Biochemical parameters for bone formation including serum osteocalcin (bone Gla protein, BGP) and alkaline phosphatase (ALP) were normal. The serum levels of tartrate-resistant acid phosphatase (TRAP), a parameter for bone resorption, were increased (4.6 KAU). The serum level of parathyroid hormone-related protein (PTHrP) was elevated (343 pmol/l). The cytokines with stimulatory effects on bone resorption, such as interleukin (IL)-1alpha, IL-1beta, IL-6, and tumor necrosis factor-alpha, were not detected. Serum Ca levels, PTHrP levels, and TRAP levels decreased with the decrease in ATL cells after chemotherapy, while serum BGP levels and ALP levels increased. On the 29th hospital day, ATL cells began to increase again. Then serum PTHrP levels, Ca levels, and TRAP levels increased, while serum BGP levels and ALP levels decreased. A marked excessive bone resorption with suppressed bone formation (uncoupling) occurred in this patient. The ATL cells produced not only PTHrP but also IL-1alpha and IL-1beta. These results suggest that PTHrP may act as a humoral factor and IL-1 may act as a local factor in bone metabolism of ATL patients.

Mammalian and viral IL-10 enhance C-C chemokine receptor 5 but down-regulate C-C chemokine receptor 7 expression by myeloid dendritic cells: impact on chemotactic responses and in vivo homing ability

The immunosuppressive and anti-inflammatory cytokine IL-10 inhibits the phenotypic and functional maturation of dendritic cells (DC) and has been reported to confer tolerogenic properties on these important professional APC. Here, we exposed murine bone marrow-derived myeloid DC to either mouse (m) or viral (v) IL-10 early during their in vitro generation in response to GM-CSF and IL-4. Both mIL-10 and vIL-10 down-regulated the expression of CCR7 mRNA determined by RT-PCR, while mIL-10 up-regulated the expression of CCR5 transcripts. These changes in CCR7 and CCR5 expression were associated with inhibition and augmentation, respectively, of DC chemotaxis toward their respective agonists, macrophage inflammatory proteins 3beta and 1alpha, while in vivo homing of DC from peripheral s.c. sites to secondary lymphoid tissue of syngeneic or allogeneic recipients was significantly impaired. Anti-mIL-10R mAb reversed the effects of mIL-10 on CCR expression and restored DC homing ability. Retroviral transduction of mIL-10- and vIL-10-treated DC to overexpress transgenic CCR7 partially restored the cells' lymphoid tissue homing ability in allogeneic recipients. However, CCR7 gene transfer did not reinstate the capacity of IL-10-treated DC to prime host naive T cells for ex vivo proliferative responses or Th1 cytokine (IFN-gamma) production in response to rechallenge with (donor) alloantigen. These findings suggest that in addition to their capacity to subvert DC maturation/function and confer tolerogenic potential on these cells, mIL-10 and vIL-10 regulate DC migratory responses via modulation of CCR expression.

Distinct pattern of p53 phosphorylation in human tumors

The protein product of the tumor suppressor gene p53 is phosphorylated on multiple residues by several protein kinases. Using a battery of 10 antibodies developed against different phosphorylated and acetylated residues of p53, we compared the pattern of p53 phosphorylation and acetylation in tumor-derived cell lines, tumor samples, and non-neoplastic cells. Irrespective of tumor types or the presence of p53 mutation, phosphorylation and acetylation of p53 was substantially higher in samples obtained from tumor tissues than those found in non-transformed samples. Among the 10 sites analysed, phosphorylation of residues 15, 81, 392, and acetylation were among the more frequent modifications. Analysis of two of the more abundant phosphorylation or acetylation sites on p53 is sufficient to detect 72% of tumor-derived p53 proteins. The distinct pattern of p53 phosphorylation and acetylation in human tumors may offer a new means to monitor the status and activity of p53 in the course of tumor development and progression.

Cervico-mediastinal bronchogenic cyst occurring in the prenatal period: report of a case

We experienced a case of cervico-mediastinal bronchogenic cyst in which a cervical cystic mass was detected by prenatal ultrasonography. On prenatal ultrasound, a unilocular, well-defined and hypoechoic mass was detected in the fetal neck. The baby was born by a normal vaginal delivery at 40 weeks of gestation, and had no respiratory distress. Radiological investigations demonstrated a cyst in the cervico-mediastinal region, which displaced the trachea to the left. At the age of 32 days, an elective resection was easily performed through a right inferior collar incision after first aspirating the contents of the cyst. Prenatal sonography showing abnormal findings is effective for identifying cysts in the perinatal period and allows for the timely resection of such cysts before respiratory distress occurs.

Differential effects of myeloid dendritic cells retrovirally transduced to express mammalian or viral interleukin-10 on cytotoxic T lymphocyte and natural killer cell functions and resistance to tumor growth

BACKGROUND

Genetic engineering of dendritic cells (DC) to express immunosuppressive molecule(s) offers potential for therapy of allograft rejection and autoimmune disease. Viral (v) interleukin (IL)-10, encoded by the Epstein-Barr virus, is highly homologous to mammalian (m) IL-10, but lacks certain of its T-cell stimulatory activities. Our aim was to evaluate and compare the influence of vIL-10 and mIL-10 gene transfer on the T-cell and natural killer (NK) cell stimulatory activity of DC, and their impact on the growth of transplantable tumors.

METHODS

Myeloid DC progenitors, propagated from the bone marrow of C57BL/6J (H2b) mice in granulocyte-macrophage colony-stimulating factor + IL-4, were transduced using retroviral supematant from the BOSC ecotropic packaging cell line. The function of the IL-b gene-modified DC was assessed by examining their ability to induce naive allogeneic T-cell proliferation and cytotoxic T lymphocyte (CTL) generation. MCA205 (H2b) sarcoma cells mixed with either vIL-10-, mIL-10-, or Zeo (control gene)-transduced DC were inoculated intradermally into C57BL/6J (syngeneic) or BALB/cJ (H2d) (allogeneic) recipients, which were monitored for tumor growth. The role of specific host effector cell populations in tumor resistance was determined by antibody depletion.

RESULTS

Compared with control gene-modified DC, both vIL-10- and mIL-10-transduced DC, which secreted the transgene product, showed reduced surface expression of MHC class II and costimulatory molecules, and impaired ability to induce T-cell proliferation. vIL-10-transduced DC were also inhibited with respect to CTL induction but did not affect the generation of NK cells. By contrast, mIL-10-transduced DC augmented CTL generation and NK cell activity. In the tumor transplant model, vIL-10-transduced DC enhanced tumor growth both in syngeneic and allogeneic hosts, whereas mIL-10-transduced cells inhibited tumor development. Depletion of CD4+ or CD8+ T cells or NK cells in mice given mIL-10-transduced DC reversed this therapeutic effect.

CONCLUSION

mIL-10 gene-modified myeloid DC promote CTL and NK cell-mediated responses and inhibit tumor growth. By contrast, vIL-10-engineered DC, which elicit diminished CTL responses and do not promote NK cell activity, seem to have therapeutic potential for inhibition of T cell-mediated immunity.

Glycemic control is a predictor of survival for diabetic patients on hemodialysis

OBJECTIVE

To investigate the impact of glycemic control on the survival of diabetic subjects with end-stage renal disease (ESRD) starting hemodialysis treatment.

RESEARCH DESIGN AND METHODS

This single-center prospective observational study enrolled 150 diabetic ESRD subjects (109 men and 41 women; age at hemodialysis initiation, 60.5 +/- 10.2 years) at start of hemodialysis between January 1989 and December 1997. The subjects were divided into groups according to their glycemic control level at inclusion as follows: good HbA1c <7.5%, n = 93 (group G), and poor HbA1c > or = 7.5%, n = 57 (group P); and survival was followed until December 1999, with a mean follow-up period of 2.7 years.

RESULTS

Group G had better survival than group P (the control group) (P = 0.008). At inclusion, there was no significant difference in age, sex, systolic blood pressure (SBP), BMI, cardio-to-thoracic ratio (CTR) on chest X-ray, and serum creatinine (Cre) or hemoglobin (Hb) levels between the two groups. After adjustment for age and sex, HbA1c was a significant predictor of survival (hazard ratio 1. 133 per 1.0% increment of HbA1c, 95% CI 1.028-1.249, P = 0.012), as were Cre and CTR.

CONCLUSIONS

Good glycemic control (HbA1c <7.5%) predicts better survival of diabetic ESRD patients starting hemodialysis treatment.

Suppression of T(h)1 cell activation and prevention of autoimmune diabetes in NOD mice by local expression of viral IL-10

Insulin-dependent diabetes mellitus in the NOD mouse model is caused by the T cell-mediated autoimmune destruction of pancreatic beta cells. Viral IL-10 (vIL-10), encoded in the Epstein-Barr virus genome, shares many of the anti-inflammatory properties of cellular IL-10, but lacks its immunostimulatory properties. In the present study, we generated transgenic (Tg) NOD mice in which vIL-10 was produced exclusively in pancreatic islets and investigated the effect of vIL-10 on the development of diabetes. The accumulation of lymphocytes around islets was more prominent, but the invasive insulitis decreased in the vIL-10 Tg mice. The incidence of diabetes was markedly reduced in the vIL-10 Tg mice, in clear contrast to the accelerated diabetes seen in the murine IL-10 Tg NOD mice. IL-12p40 and IFN-gamma mRNA levels were decreased in pancreata of the vIL-10 Tg mice, although CD4 mRNA level was markedly increased. These results suggest that locally produced vIL-10 induced leukocyte migration, but inhibited the activation of T(h)1, probably through suppressing the production of IL-12. They indicate that vIL-10 may well be superior to cellular IL-10 in the treatment of autoimmune diabetes. The vIL-10 Tg NOD mice should provide a useful tool for understanding the differential action of vIL-10 versus cellular IL-10.

Interleukin 12 gene therapy of cancer by peritumoral injection of transduced autologous fibroblasts: outcome of a phase I study

A phase I dose-escalation clinical trial of peritumoral injections of interleukin 12 (IL-12)-transduced autologous fibroblasts was performed in patients with disseminated cancer for whom effective treatment does not exist. The goals of this study were to assess the safety and toxicities as well as the efficacy, and ancillarily the immunomodulatory effects, of peritumoral IL-12 gene transfer. Primary dermal fibroblasts cultured from the patients were transduced with retroviral vector carrying human IL-12 genes (p35 and p40) as well as the neomycin phosphotransferase gene (TFG-hIL-12-Neo). Patients received four injections at intervals of 7 days. Nine patients were enrolled in this dose-escalation study, with secreted IL-12 doses ranging from 300 ng/24 hr for the first three patients to 1000, 3000, and 5000 ng/24 hr for two patients in each subsequent dosage level. Although a definite statement cannot be made, there appears to be perturbation of systemic immunity. Also, the locoregional effects mediated by tumor necrosis factor alpha (TNF-alpha) and CD8+ T cells were observed with tumor regression. Treatment-related adverse events were limited to mild to moderate pain at the injection site; clinically significant toxicities were not encountered. Transient but clear reductions of tumor sizes were observed at the injected sites in four of nine cases, and at noninjected distant sites in one melanoma patient. Hemorrhagic necrosis of tumors was observed in two melanoma patients. These data indicate that gene therapy by peritumoral injection of IL-12-producing autologous fibroblasts is feasible, and promising in patients with advanced cancer.

Impact of insulin resistance and nephropathy on homocysteine in type 2 diabetes

OBJECTIVE

To assess the impacts of insulin resistance and renal function on plasma total homocysteine (tHcy) levels in patients with type 2 diabetes with a wide range of nephropathy.

RESEARCH DESIGN AND METHODS

Plasma tHcy levels were measured using the enzyme immunoassay method in 75 patients with type 2 diabetes and compared with those in 54 healthy control subjects. Insulin sensitivity indexes were assessed in patients with type 2 diabetes by hyperinsulinemic-euglycemic clamp using artificial pancreas.

RESULTS

Plasma tHcy levels and their log-translormed values (log tHcy) were significantly higher in all patients with diabetes than in control subjects (tHcy, 12.0 +/- 0.7 [SE] vs. 8.7 +/- 0.3 micromol/l, P < 0.0001; log tHcy, 1.040 +/- 0.021 vs. 0.920 +/- 0.016 micromol/l, P < 0.0001). Plasma tHcy levels in patients with diabetes were significantly increased according to degree of nephropathy (P < 0.0001). On simple regression analyses, log tHcy correlated with insulin sensitivity indexes (r = -0.319, P = 0.005) as well as creatinine clearance (r = 0.634, P < 0.0001) in all patients with diabetes. Multiple regression analyses showed that insulin sensitivity indexes (beta = -0.245) as well as creatinine clearance were independent contributors to log tHcy in all patients with diabetes (R2 = 0.750, P < 0.0001). For the 59 patients with diabetes with creatinine clearance >60 ml/min, insulin sensitivity indexes were also shown to be a significant contributor to log tHcy (beta = -0.438, R2 = 0.561, P < 0.001).

CONCLUSION

Insulin resistance and renal function are independent determinants of tHcy levels in patients with type 2 diabetes.

Viral IL-10-induced immunosuppression requires Th2 cytokines and impairs APC function within the allograft

Previous reports demonstrated that retroviral mediated gene transfer of viral IL-10 (vIL-10) prolongs allograft survival by decreasing donor-specific cytotoxic T lymphocyte precursor (CTLp) and IL-2-secreting helper T lymphocyte precursor (HTLp) frequency within graft-infiltrating cells (GIC). This report now shows that vIL-10 efficacy is dependent on CD4(+) T cells, suggesting that immunosuppression may involve a switch from a Th1 to a Th2 alloresponse. In support of this, anti-IL-4 or anti-murine IL-10 (anti-mIL-10) mAbs, but not anti-IFN-gamma mAb, administered at the time of vIL-10 gene transfer prevents enhanced graft survival. Because Th switching involves APC function, GIC were examined for their ability to present alloantigen. GIC from vIL-10-treated grafts were shown to be mostly of recipient (CBA) origin, yet were unable to elicit alloproliferative responses from donor type (C57BL/6) or third party (BALB/c) responders. The inability of vIL-10-treated GIC to stimulate the MLR was not due to the generation of negative regulatory cells or the production of immunosuppressive cytokines such as IL-4, mIL-10, or TGFbeta. Using fractionated GIC subpopulations, the number of recipient type cells in the allografts was modestly reduced by vIL-10 gene transfer, while maintaining both APC phenotype and alloantigen presenting function. Conversely, after vIL-10 gene transfer, donor type GIC were unable to participate in direct alloantigen presentation. Therefore, local immunosuppression induced by vIL-10 gene transfer is CD4 T cell and IL-4 and mIL-10 dependent, and impairs direct alloantigen presentation through an alteration of donor type APC function.

A malignant rhabdoid tumor of the kidney occurring concurrently with a brain tumor: report of a case

Malignant rhabdoid tumor of the kidney (MRTK) is one of the most lethal neoplasms to occur in young infants. Cases of MRTK accompanying an embryonal tumor in the central nervous system have occasionally been described. We present herein an interesting case of MRTK that was clinically diagnosed preoperatively. A male infant aged 6 months with both a midline brain tumor and a renal neoplasm was transferred to our institution. Although roentgenographic evaluation suggested that the renal lesion was a Wilms' tumor, midkine (MK), a growth and differentiation factor characteristically present in the urine of patients with Wilms' tumor, was not detected. A preoperative diagnosis of MRTK was established based on the lack of urinary MK in addition to the typical clinical features of the young age and the concurrent brain tumor.

[A case of renal oncocytoma with synchronous contralateral renal cell carcinoma]

A case of bilateral, synchronous renal cell carcinoma and oncocytoma is reported. The patient was a 70-year-old woman. Computed tomographic scan revealed bilateral low density masses, which had a diameter of approximately 4 cm (right kidney), and 2.5 cm (left kidney). We suspected bilateral renal cell carcinomas, and performed, right nephrectomy and left enucleation of the tumor. Pathological diagnosis was right renal cell carcinoma and left oncocytoma. To our knowledge only 5 previous cases of renal cell carcinoma associated with oncocytoma have been reported in Japan. Two cases were metachronous and three cases were unilateral and synchronous. This is the first reported case of bilateral, synchronous renal cell carcinoma and oncocytoma.

Potent antitumor effects of intra-arterial injection of fibroblasts genetically engineered to express IL-12 in liver metastasis model of rat: no additional benefit of using retroviral producer cell

Interleukin-12 (IL-12) mediates significant antitumor effects in animal models but associated with dose-dependent toxicity in human. To achieve local expression of IL-12 at the tumor site without systemic toxicity, we performed intra-arterial administration of fibroblasts genetically engineered to produce IL-12 protein with or without retrovirus (CRIP- IL-12 or 3T3-IL-12) in liver metastasis model. Rat breast cancer cells ( MADB - 106) were injected into the portal vein of syngeneic Fisher rats on day 0, and fibroblasts were injected into the hepatic artery on day 7. On day 21, liver weight and number of liver tumors were examined. As controls, CRIP cells expressing retrovirus carrying lacZ marker gene (CRIP-lacZ) or saline (Hanks balanced salt solution, HBSS) were injected. Administration of CRIP-IL-12 significantly reduced tumor metastasis in liver measured by number of foci (CRIP- IL-12: 45.2 +/- 36.7, CRIP-lacZ: >250, HBSS: >250, P<.05) and by liver weight (CRIP-IL-12: 13.0+/-2.5 g, CRIP-lacZ: 30.4+/-8.5 g, HBSS: 26.0+/-7.6 g, P<.05). 3T3-IL-12, which produced only IL-12 protein but not IL-12 retrovirus, also had significant antitumor effects equivalent to CRIP-IL-12. Intra-arterial injection of IL-12--producing fibroblasts into the liver may be an effective therapy for liver tumors reducing systemic toxicity, and could be developed for clinical application.

Persistent increase in bone turnover in Graves' patients with subclinical hyperthyroidism

Hyperthyroid patients exhibit accelerated bone loss by increased bone turnover, and normalization of thyroid function is associated with a significant attenuation of increased bone turnover, followed by an increase in bone mineral density. However, of patients with Graves' disease (GD) maintained on antithyroid drug (ATD) treatment, some exhibit persistent suppression of TSH long after normalization of their serum free T3 (FT3) and free T4 (FT4) levels. The aim of this study was to examine whether bone metabolism is still enhanced in TSH-suppressed premenopausal GD patients with normal FT3 and FT4 levels after ATD therapy (n = 19) compared with that in TSH-normal premenopausal GD patients (n = 30), and to evaluate the relationship between serum TSH receptor antibody (TRAb), an indicator of disease activity of GD, and various biochemical markers of bone metabolism. No difference was found between the two groups in serum Ca, phosphorus, or intact PTH, or in urinary Ca excretion. Serum bone alkaline phosphatase (B-ALP), bone formation markers, and urinary excretions of pyridinoline (U-PYD) and deoxypyridinoline (U-DPD), which are bone resorption markers, were significantly higher in the TSH-suppression group than in the TSH-normal group (B-ALP, P < 0.05; U-PYD, P < 0.001; U-DPD, P < 0.001). For the group of all GD patients enrolled in this study, TSH, but neither FT3 nor FT4, exhibited a significant negative correlation with B-ALP (r = -0.300; P < 0.05), U-PYD (r = -0.389; P < 0.05), and U-DPD (r = -0.446; P < 0.05), whereas TRAb exhibited a highly positive and significant correlation with B-ALP (r = 0.566; P < 0.0001), U-PYD (r = 0.491; P < 0.001), and U-DPD (r = 0.549; P < 0.0001). Even in GD patients with normal TSH, serum TRAb was positively correlated with B-ALP (r = 0.638; P < 0.001), U-PYD (r = 0.638; P < 0.001), and U-DPD (r = 0.641; P < 0.001). In conclusion, it is important to achieve normal TSH levels during ATD therapy to normalize bone turnover. TRAb was not only a useful marker for GD activity, but was also a very sensitive marker for bone metabolism in GD patients during ATD treatment.

Rare somatic inactivation of the multiple endocrine neoplasia type 1 gene in secondary hyperparathyroidism of uremia

The molecular pathway of autonomous growth of the parathyroid glands in uremic patients is poorly understood. Loss of heterozygosity at the recently identified multiple endocrine neoplasia type 1 (MEN1) gene locus on chromosome 11q13 has been found in a subset of parathyroid glands from patients with refractory hyperparathyroidism. To clarify the role of the MEN1 gene in parathyroid tumorigenesis, we analyzed 81 parathyroid glands from 22 Japanese uremic patients for allelic loss on chromosomal arm 11q13 DNA using 3 flanking markers (PYGM, D11S4946, and D11S449) and for mutations of the MEN1-coding exons by PCR-based single strand conformation polymorphism analysis and sequencing. Allelic loss on 11q13 was observed in 6 glands (7%), and 1 of 6 demonstrated a previously unrecognized somatic frameshift deletion (331delG) of the MEN1 gene. This mutation would probably result in a nonfunctional menin protein, consistent with a tumor suppressor mechanism. Clinical and pathological characteristics of hyperparathyroidism were unrelated to the presence or absence of loss of heterozygosity on 11q13 and MEN1 gene mutations. These observations indicate that somatic inactivation of the MEN1 gene contributes to the pathogenesis of uremia-associated parathyroid tumors, but its role in this disease appears to be very limited.

Telomerase activity in primary and secondary glioblastomas multiforme as a novel molecular tumor marker

OBJECT

Telomerase activity is responsible for cell immortality. To examine the role of telomerase in the carcinogenesis of human glioblastomas multiforme (GBMs), the authors studied telomerase activity, telomerase component expression, and telomere lengths in 42 GBM samples.

METHODS

In all samples, EGFR and MDM2 amplifications and overexpressions were examined using Southern and Northern blot analyses. The p53 mutation was analyzed using polymerase chain reaction-single strand conformational polymorphism and by direct sequence analysis. Specimens of tissues were immunostained with p53, EGFR, and MDM2 antibodies. Allelic loss on chromosomes 17p and 10 was assessed by loss of heterozygosity (LOH) assays. Telomerase activity, expression of its components (human telomerase reverse transcriptase [hTERT], human telomerase RNA component [hTERC], and telomerase-associated protein [TEP1]), and telomere lengths were analyzed using the telomeric repeat amplification protocol (TRAP)-hybridization protection assay, reverse transcription-polymerase chain reaction, and Southern blot analysis. According to the results of assessments of EGFR and MDM2 amplifications, p53 mutation, LOHs in chromosomes 17p and 10, and the clinical course of the disease, the 42 samples were classified into 22 primary and 20 secondary glioblastomas. Twenty-six (61.9%) of all 42 samples demonstrated detectable telomerase activity during the TRAP assay. Secondary GBMs displayed significantly higher levels of telomerase activity and hTERT expression than primary GBMs. Tumors with a p53 gene mutation demonstrated significantly higher telomerase activity than those without a p53 mutation. Four samples with a codon 175 mutation demonstrated an exceptionally high amount of telomerase activity. In secondary GBMs, the increase in telomerase activity and the hTERT expression level correlated with the increased frequency of p53 mutations. There was no significant difference in telomere length between primary and secondary GBMs.

CONCLUSIONS

These results suggest that telomerase activity and p53 mutations both play important roles in the multistep carcinogenesis of GBMs. Telomerase activity and hTERT expression may be considered as novel distinctive factors in human GBMs.

Rapid generation of potent and tumor-specific cytotoxic T lymphocytes by interleukin 18 using dendritic cells and natural killer cells

We hypothesized that antitumor-specific immunity, which is induced by interleukin (IL) 18 treatment in murine tumor models, is promoted by enhancing natural killer (NK)-mediated destruction of tumor and delivery to dendritic cells (DCs). These activated and antigen-pulsed DCs then critically and optimally induce an adoptive immune response, positioning IL-18 as an important bridge between the innate and adoptive immune response. The effect of IL-18 added to cultures of live tumor cells (MCA205, a mouse sarcoma cell line), NK cells, DCs, and T cells was assessed. When recombinant (r) mIL-18 protein was added to this culture, potent NK cytolytic activity with subsequent generation of CTLs was observed in a dose-dependent manner. Without introduction of either rmIL-18 or NK cells into this culture, systemic cytolytic activity was significantly decreased. Following the absence of direct contact of either NK cells or DCs with other cells in this cooperative coculture system using transwell, the systemic cytolytic activity of both NK cells and CTLs was greatly suppressed. The cytolysis mediated by effector cells harvested after completion of the culture was primarily restricted to MHC class I and highly specific for the tumor cells used in the coculture. Furthermore, we examined the efficiency in the induction of cytolytic T cells of other established IFN-gamma inducing T-cell growth factors, IL-2, and IL-12 in this culture system and compared them with that mediated by IL-18. Neither IL-2 nor IL-12 induced tumor-specific cytolytic T cells to the same degree as that mediated by IL-18. Efficacy of this system in induction of tumor-specific CTLs was also observed in the system using MC38 adenocarcinoma cells. These results are consistent with the notion that IL-18 induces tumor-specific immunity through enhancing NK activity, which in turn mediates tumor cell death and activates and primes DCs.

Immuno-histochemical detection of human telomerase reverse transcriptase in human liver tissues

Although telomerase activity in hepatocellular carcinoma (HCC) increases in accordance with degree of histological undifferentiation, it is unknown whether the level of telomerase activity in HCC reflects of the degree of activity in individual cells or the frequency of telomerase-positive HCC cells. Non-cancerous liver tissues exhibit low but significant levels of telomerase activity, but the nature of telomerase-positive cells in these tissues is unclear. In this study, we performed immunohistochemical staining using specific antibody against telomerase reverse transcriptase (hTERT) protein in 15 HCC samples and 13 adjacent non-cancerous liver tissues. There were hTERT-positive hepatocytes, though very low frequency, in non-cancerous liver tissues. The frequencies in hTERT positive hepatocytes were very well correlated with clinicopathological parameters and telomerase activity levels: the average frequencies of chronic hepatitis was 0.2%, liver cirrhosis 0.2%, well-differentiated HCC 3.0%, moderately differentiated HCC 28%, and poorly differentiated HCC 95%. The intensity of staining varied among cells within a given specimen, and correlation with degree of histological undifferentiation was less obvious. Portions of migrating lymphocytes and biliary epithelial cells were also hTERT-positive. These findings indicate that the upregulation of telomerase activity with degree of undifferentiation of HCC is mainly due to the increase in frequency of hTERT positive HCC cells.

Feasibility of CTLA4Ig gene delivery and expression in vivo using retrovirally transduced myeloid dendritic cells that induce alloantigen-specific T cell anergy in vitro

Dendritic cells (DC) are highly specialised, bone marrow (BM)-derived antigen-presenting cells (APC) that initiate and regulate immune responses. They provide costimulatory signals (in particular, CD40 and the CD28 ligands CD80 and CD86) necessary for naive T cell activation. Functional expression of CD80 and CD86 is blocked by the fusion protein cytotoxic T lymphocyte antigen 4-immunoglobulin (CTLA4Ig), that promotes tolerance induction in animals. Here, replicating mouse (B10; H2b) myeloid DC progenitors, were retrovirally transduced to express CTLA4Ig using the centrifugal enhancement method. Gene product was detected by immunocyto- or histochemistry. Maximal DC transduction efficiency was 62%. Compared with control, zeomycin-resistance gene (Zeo)-transduced DC, CTLA4Ig-expressing cells showed markedly impaired capacity to stimulate naive allogeneic (C3H; H2k) T cell proliferation and cytotoxic T lymphocyte (CTL) generation. Their ability to induce alloantigen-specific T cell hyporesponsiveness was reversed by exogenous IL-2 in secondary mixed leukocyte reactions (MLR). Following local (s.c.) transfer to allogeneic recipients, the genetically modified DC trafficked to T cell areas of draining lymphoid tissue, where transgene expression was detected. Ex vivo analysis of proliferative and CTL responses revealed donor-specific inhibition of alloimmune reactivity by the CTLA4Ig-transduced DC. This effect was associated with marked inhibition of interferon (IFN)-gamma production, but significant augmentation of IL-4 and IL-10 secretion. Thus, retroviral transduction of DC permits in vivo delivery of CTLA4Ig to the precise microenvironment where antigen (Ag) presentation occurs. Comparatively nonimmunogenic retroviral vectors, that allow permanent transgene expression in DC, and promote localized delivery of the immunosuppressive transgene product, promote immune deviation and Ag-specific T cell hyporesponsiveness.

The design and synthesis of a new tumor-selective fluoropyrimidine carbamate, capecitabine

To identify an orally available fluoropyrimidine having efficacy and safety profiles greatly improved over those of parenteral 5-fluorouracil (5-FU: 1), we designed a 5-FU prodrug that would pass intact through the intestinal mucisa and be sequentially converted to 5-FU by enzymes that are highly expressed in the human liver and then in tumors. Among various N4-substituted 5'-deoxy-5-fluorocytidine derivatives, a series of N4-alkoxycarbonyl derivatives were hydrolyzed to 5'-deoxy-5-fluorocytidine (5'-DFCR: 8) specifically by carboxylesterase, which exists preferentially in the liver in humans and monkeys. Particularly, derivatives having an N4-alkoxylcarbonyl moiety with a C4-C6 alkyl chain were the most susceptible to the human carboxylesterase. Those were then converted to 5'-deoxy-5-fluorouridine (5'-DFUR: 4) by cytidine deaminase highly expressed in the liver and solid tumors and finally to 5-FU by thymidine phosphorylase (dThdPase) preferentially located in tumors. When administered orally to monkeys, a derivative having the N4-alkoxylcarbonyl moiety with a C5 alkyl chain (capecitabine: 6) The highest AUC and Cmax for plasma 5'-DFUR. In tests with various human cancer xenograft models, capecitabine was more efficacious at wider dose ranges than either 5-FU or 5'-DFUR and was significantly less toxic to the intestinal tract than the others in monkeys.

Multilocular cystic adenomyoma of the pelvic cavity: A rare clinical and histological entity in a young man

We report a large complex cystic pelvic mass encountered in a 16-year-old man complaining of perineal discomfort. A large and elastic hard mass was palpated on the right anterior wall of the rectum with no discernible prostate on digital rectal examination. Prostatic tumor markers were elevated. Excretory urography and urethrocystography showed a filling defect with a smooth edge on the right side of the bladder. Magnetic resonance imaging demonstrated a mass with a mosaic pattern between the right side of the bladder and the rectum. We performed ultrasound-guided transrectal needle core biopsy of the mass. The pathologist suspected hyperplastic glandular epithelium of prostatic origin with focal inflammatory cell infiltration, but there was no sign of malignancy. We thought that the tumor arose from the prostate. Surgery was successfully performed. The tumor was located on the right side of the pelvic cavity and adhered to the right lobe of the seminal vesicle. En bloc excision was performed. This lesion histologically proved to be a multilocular prostatic tissue with a seminal vesicle component, without communication to the surrounding tissue. Such a lesion has not previously been reported in the literature.

CC chemokine receptor-7 on dendritic cells is induced after interaction with apoptotic tumor cells: critical role in migration from the tumor site to draining lymph nodes

Dendritic cells (DCs) are very potent antigen-presenting cells and play critical roles in regulating immune responses in cancer. The migrating of DCs from the tumor site to the lymphoid organs is believed to be one of the critical events. To examine this important DC function in tumor situations, bone marrow-derived DCs, cultured for 6 days with granulocyte macrophage colony-stimulating factor and interleukin 4, were inoculated at the tumor site. We have shown (Y. Nishioka et al., Cancer Res., 59: 40354041, 1999) that DCs can migrate from tumor site to the draining lymph nodes within 24 h (approximately 0.1% of administrated DCs). The DCs then form clusters with adjacent lymphoid cells, which produce IFN-gamma (1500-3200pg/10(6) cells/48 h) in response to tumor stimulation. The number of the DCs migrating into lymph nodes were greater when they were inoculated into the tumor rather than the skin. Coculture of DCs and apoptotic tumor cells resulted in decreased expression of CC chemokine receptor (CCR) 1 and increased CCR7 expression at mRNA level without alteration in other phenotypical markers on DCs. Chemotaxis assay showed that CCR7 ligands, macrophage inflammatory protein 3beta and secondary lymphoid-tissue chemokine significantly (P < 0.05) induced the migration of DCs when cocultured with apoptotic tumor cells. To directly examine the involvement of CCR7 expression in DC migration, we investigated the functions of DCs genetically modified to express high levels of CCR7. CCR7 transduction promotes DC migration in response to relevant ligands in vitro and in vivo. These results suggest that the CCR7 expression of DCs is enhanced with direct contact with apoptotic tumor cells and may have a critical role for DC migrating to regional lymph nodes. The means to promote DC delivery to tumor and to nodal sites represent novel targets for the biological therapy of cancer.