Effects of toremifene (TOR) and tamoxifen (TAM) on serum lipids in postmenopausal patients with breast cancer

This study clarified the difference in the effects on serum lipids between toremifene (TOR) and tamoxifen (TAM). To remove influencing factors, we investigated adjuvant therapy for hormone receptor-positive patients with breast cancer without lymph node metastasis. The subjects were 65 patients who were enrolled in a multicenter randomized comparative study between April 1997 and March 2001. As adjuvant therapy, 20 mg of TAM or 40 mg of TOR was administered for 1 year. The levels of triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A-1 (Apo A-1), apolipoprotein A(Apo B), and lipoprotein a (Lp(a)) were measured prior to administration and 3, 6, and 12 months after the start of administration. TC, LDL-C, Lp(a) and Apo B significantly decreased from the third month of administration compared with values before the start of administration in both the TOR and TAM groups. HDL-C significantly increased from the third month only in the TOR group. TG significantly increased in the TAM group but significantly decreased in the TOR group in the 12th month of administration. When these two groups were compared, HDL-C was significantly higher (p < 0.01) and TG was significantly lower (p < 0.01) in the TOR group in the 12th month. Improvement of abnormal values of TG, HDL-C and LDL-C was better in the TOR group than in the TAM group after administration for 12 months. The effect on lipid metabolism showed different profiles between the two selective estrogen receptor modulators (SERMs), and TOR gave better results than TAM.

Connectivities and synchronous firing in cortical neuronal networks

Network connectivities ((-)k) of cortical neural cultures are studied by synchronized firing and determined from measured correlations between fluorescence intensities of firing neurons. The bursting frequency (f) during synchronized firing of the networks is found to be an increasing function of (-)k. With f taken to be proportional to (-)k, a simple random model with a (-)k dependent connection probability p((-)k).has been constructed to explain our experimental findings successfully.

Construction of a ribozyme-expression system that effectively transports ribozymes to the cytoplasm

In our previous studies, it was demonstrated that the activity of a ribozyme in vivo was governed by several parameters, which include a high level-expression of ribozyme, the intracellular stability of the ribozyme and colocalization of the ribozyme with its target RNA in the same cellular compartment. To generate ribozymes with significant activity in vivo, we have developed a ribozyme-expression system based on a human tRNA(Val) promoter. Our tRNA-embedded ribozymes produced by our ribozyme-expression system remain relatively stable in cultured cells with half-lives longer than 30 min. Moreover, tRNA-ribozymes with a cloverleaf structure were efficiently exported from the nucleus to the cytoplasm, where they would effectively cleave target RNAs. In the present study, we investigated the relationship between the secondary structure of the tRNA-ribozymes and the transport efficacy of them in mammalian cells by using a screening system in vivo. Furthermore, we also investigated the mechanism of the export of tRNA-embedded ribozymes both in mammalian cells and in Xenopus oocytes.

A thirteen-week oral toxicity study of annatto extract (norbixin), a natural food color extracted from the seed coat of annatto (Bixa orellana L.), in Sprague-Dawley rats

A subchronic oral toxicity study of annatto extract (norbixin), a natural food color, was conducted. Groups of 10 male and 10 female Sprague-Dawley rats were fed annatto extract at dietary levels of 0, 0.1, 0.3 and 0.9% for 13 weeks. There were no treatment-related adverse effects on body weight, food and water consumption, ophthalmology and hematology data. Blood biochemical analysis revealed changes in rats of both sexes confined to the 0.9% and 0.3% groups, including increased alkaline phosphatase, phospholipid, total protein, albumin and albumin/globulin ratio. Marked elevation in absolute and relative liver weights was also found in both sexes of the 0.9% and 0.3% groups, but not the 0.1% group. Hepatocyte hypertrophy was evident and an additional electron microscopic examination demonstrated this to be linked to abundant mitochondria after exposure to a dietary level of 0.9% annatto extract for 2 weeks. Thus, the No-Observed-Adverse-Effect-Level (NOAEL) was judged to be a dietary level of 0.1% (69 mg/kg body weight/day for males, 76 mg/kg body weight/day for females) of annatto extract (norbixin) under the present experimental conditions.

Mild hypercholesterolemia is an early risk factor for the development of Alzheimer amyloid pathology

BACKGROUND

Epidemiologic and experimental data suggest that cholesterol may play a role in the pathogenesis of AD. Modulation of cholesterolemia in transgenic animal models of AD strongly alters amyloid pathology.

OBJECTIVE

To determine whether a relationship exists between amyloid deposition and total cholesterolemia (TC) in the human brain.

METHODS

The authors reviewed autopsy cases of patients older than 40 years and correlated cholesterolemia and presence or absence of amyloid deposition (amyloid positive vs amyloid negative subjects) and cholesterolemia and amyloid load. Amyloid load in human brains was measured by immunohistochemistry and image analysis. To remove the effect of apoE isoforms on cholesterol levels, cases were genotyped and duplicate analyses were performed on apoE3/3 subjects.

RESULTS

Cholesterolemia correlates with presence of amyloid deposition in the youngest subjects (40 to 55 years) with early amyloid deposition (diffuse type of senile plaques) (p = 0.000 for all apoE isoforms; p = 0.009 for apoE3/3 subjects). In this group, increases in cholesterolemia from 181 to 200 almost tripled the odds for developing amyloid, independent of apoE isoform. A logistic regression model showed consistent results (McFadden rho2 = 0.445). The difference in mean TC between subjects with and without amyloid disappeared as the age of the sample increased (>55 years: p = 0.491), possibly reflecting the effect of cardiovascular deaths among other possibilities. TC and amyloid load were not linearly correlated, indicating that there are additional factors involved in amyloid accumulation.

CONCLUSIONS

Serum hypercholesterolemia may be an early risk factor for the development of AD amyloid pathology.

Testicular metastasis from squamous cell carcinoma of the lung

We present a case of squamous cell carcinoma of the testis that metastasized from lung cancer. The patient, who had received left pneumonectomy 2 years earlier for squamous cell carcinoma (SCC) of the lung, developed pulmonary metastasis, which was treated with chemotherapy. Although the recurrence regressed after treatment, the testicular tumor progressed gradually. Left radical orchiectomy was performed. Pathological examination revealed metastatic SCC. Testicular metastasis from lung cancer is a very rare disease.

Recognition of engineered tRNAs with an extended 3' end by Exportin-t (Xpo-t) and transport of tRNA-attached ribozymes to the cytoplasm in somatic cells

Our recent analysis indicates that the cytoplasmic localization of tRNA-attached ribozymes (tRNA-Rz) is critical for its high-level intracellular activity, suggesting that mature mRNAs in the cytoplasm are more accessible to ribozymes than pre-mRNAs in the nucleus (Kato et al. J. Biol. Chem. 2001, 276, 15378-15385; Kuwabara et al. Nucleic Acids Res. 2001, 29, 2780-2788). Although studies in Xenopus oocytes led to the proposal that only correctly processed mature tRNAs are exported from nuclei in a RanGTP-dependent manner (Lund and Dahlberg Science 1998, 282, 2082-2085), our tRNA-Rz with an extended 3' end can also be exported to the cytoplasm in somatic cells. Xpo-t/RanGTP bound to tRNA-attached ribozymes in vitro and in somatic cells, with recognition basically resembling the recognition of mature tRNAs. In contrast, no binding to tRNA-attached ribozymes occurred in Xenopus oocytes. The injection of a nuclear extract of Xenopus oocytes together with tRNA-attached ribozymes inhibited the export of tRNA-attached ribozymes but not mature tRNAs in somatic cells, suggesting the existence of an inhibitor(s) of the Xpo-t-dependent export pathway. Moreover, the inhibitor(s) appears responsible for a proofreading mechanism that operates in oocytes.

Steroid-induced elevation of glucose in Alzheimer's disease: relationship to gender, apolipoprotein E genotype and cognition

Glucose and insulin may play an important role in the pathophysiology and symptomatology of Alzheimers disease (AD), and prior studies suggest interactions among glucose, insulin, gender and apolipoprotein E genotype. We analyzed the relationship between steroid-induced glucose elevation and gender, presence of the apolipoprotein E epsilon 4 (APOE-4) allele and cognition using data from a multicenter trial of prednisone therapy in AD. The low-dose prednisone regimen (initial dose: 20 mg/day, maintenance dose: 10 mg/day) caused a moderate increase in random blood glucose (mean post-baseline glucose 115 mg/dl). There was a significant interaction between rise in glucose, gender and presence of the APOE-4 allele. There was no important relationship between glucose and cognitive function at baseline or with prednisone treatment. Meta-analysis including data from three other AD trials showed a small influence of random blood glucose on cognitive scores. These results support a relationship between gender, apolipoprotein E genotype and glucose metabolism, but do not indicate that mild changes in glucose have an important impact on cognitive function.

Comparison between high-resolution helical CT and pathology in breast examination

PURPOSE

To determine whether high-resolution helical CT can show the architectural features of breast carcinomas of non-limited extent (non-BCLE) and to establish the CT characteristic morphology of non-BCLE.

MATERIAL AND METHODS

We prospectively studied high-resolution helical CT of 136 invasive breast carcinomas before breast-conserving surgery. Non-BCLE were defined as ductal carcinomas in situ and invasive carcinomas beyond 1 cm from the edge of the dominant mass. Non-BCLE were defined as positive if enhanced beyond 1 cm from the edge of the focal enhancement on CT. After surgical resection, specimens were sliced in serial sections at 5-mm intervals, and the gross morphology and histology were correlated with the appearance of the preoperative CT lesion images.

RESULTS

Non-BCLE were present in 47 invasive carcinomas. The sensitivity and specificity of non-BCLE evaluation by high-resolution helical CT were 70% and 89%, respectively. The morphology of non-BCLE on CT agreed with histologic findings. The morphological pattern on CT significantly correlated with intraductal tumor density adjacent to invasive tumor.

CONCLUSION

Comparison of high-resolution helical CT with histologic data suggests that demonstration of a non-BCLE morphology can make the CT breast carcinoma local staging more accurate.

Comparison between high-resolution helical CT and pathology in breast examination

PURPOSE

To determine whether high-resolution helical CT can show the architectural features of breast carcinomas of non-limited extent (non-BCLE) and to establish the CT characteristic morphology of non-BCLE.

MATERIAL AND METHODS

We prospectively studied high-resolution helical CT of 136 invasive breast carcinomas before breast-conserving surgery. Non-BCLE were defined as ductal carcinomas in situ and invasive carcinomas beyond 1 cm from the edge of the dominant mass. Non-BCLE were defined as positive if enhanced beyond 1 cm from the edge of the focal enhancement on CT. After surgical resection, specimens were sliced in serial sections at 5-mm intervals, and the gross morphology and histology were correlated with the appearance of the preoperative CT lesion images.

RESULTS

Non-BCLE were present in 47 invasive carcinomas. The sensitivity and specificity of non-BCLE evaluation by high-resolution helical CT were 70% and 89%, respectively. The morphology of non-BCLE on CT agreed with histologic findings. The morphological pattern on CT significantly correlated with intraductal tumor density adjacent to invasive tumor.

CONCLUSION

Comparison of high-resolution helical CT with histologic data suggests that demonstration of a non-BCLE morphology can make the CT breast carcinoma local staging more accurate.

Expression of c-kit protein in proliferative lesions of human breast: sexual difference and close association with phosphotyrosine status

PURPOSE

The c-kit gene which codes transmembrane tyrosine kinase receptor protein plays an important role in several types of normal and/or neoplastic human tissues. We examined the expression patterns of c-kit protein in proliferative lesions of human breast tissues in both sexes.

METHODS

The localization of c-kit protein was examined immunohistochemically in human breast, consisting of 366 normal tissue, 156 benign lesions (fibroadenoma, fibrocystic change, intraductal papilloma, benign phyllodes tumor, and gynecomastia), 13 borderline diseases (atypical ductal hyperplasia, atypical lobular hyperplasia, and borderline malignant phyllodes tumor), and 197 malignant lesions (non-invasive and/or invasive ductal carcinoma and malignant phyllodes tumor).

RESULTS

In normal tissues and benign proliferative lesions, c-kit product was consistently detected on epithelial cell membranes and/or cytoplasms regardless of gender difference. In contrast, we failed to find c-kit product in female borderline epithelial lesions, including atypical lobular hyperplasia, or in female malignant lesions, except for two carcinomas. In situ hybridization analysis of c-kit mRNA in female tissues gave results comparable to those obtained by immunohistochemistry. On the other hand, c-kit product was consistently detected in male benign and malignant proliferative lesions. Apart from the female breast carcinomas which lacked c-kit, c-kit expression was almost always accompanied by positivity for phosphotyrosine in the breast tissues examined, suggesting possible phosphorylation of tyrosine residues of the c-kit receptor protein.

CONCLUSIONS

Loss of c-kit product was related to malignant transformation in female breast, but not in the case of male breast. We suggest that the oncogenesis pathway of breast epithelium is different between males and females in terms of c-kit expression.

Isolation of novel mouse genes associated with ectopic ossification by differential display method using ttw, a mouse model for ectopic ossification

Mouse mutant ttw (tiptoe walking) is an excellent model for ectopic ossification. This mutant exhibits ossification in various soft tissues, which is histologically similar to human OPLL (ossification of posterior longitudinal ligament of the spine). We previously reported that ttw is caused by a nonsense mutation of the nucleotide pyrophosphatase (ENPP1) gene, and that a polymorphism of the human ENPP1 gene is associated with OPLL. These facts indicate that ENPP1 regulates ectopic ossification in vivo; however, the mechanism is unclear. ENPP1 is an ectoenzyme that generates phosphate (Pi) and pyrophosphate (PPi). PPi is a strong inhibitor of ossification. Abnormal Pi metabolism is observed in patients with OPLL, and diseases with abnormal Pi metabolism such as hypophosphatemic rickets are frequently complicated by ectopic ossification. These lines of evidence suggest Pi-PPi metabolism associated with ENPP1 may play an important role in regulation of ectopic ossification. To clarify the molecular mechanism of ectopic ossification in ttw, we examined the effect of dietary phosphate and calcium on the ttw phenotype and found a high dietary phosphate-accelerated ectopic ossification. Then we examined genes associated with the enhanced ossification in ttw on a high phosphate diet by a differential display method. We identified nine mouse genes; six genes were up-regulated by the high phosphate diet, and three were down-regulated. Six of the nine genes were novel and we cloned and characterized them. Two of the genes were highly specific to cartilage, suggesting their specific role in enchondral ossification. Our identification of the novel genes would give novel insight into the mechanism of ectopic ossification and etiology of OPLL.

Deletion analysis of the enolase gene (enoA) promoter from the filamentous fungus Aspegillus oryzae

The enolase gene (enoA) is one of the most strongly expressed genes in Aspergillus oryzae. To elucidate the transcription regulatory element for this strong expression and the process of glucose induction, the transcription activity of a series of truncated enoA promoters was measured by using the Escherichia coli uidA gene as a reporter. Deletion of a 104-bp region located -224 nt to -121 nt upstream of the translation initiation site caused both a drastic decrease in the beta-glucuronidase (GUS) activity and a loss of glucose induction. Northern blot analysis confirmed that the decrease in GUS activity was achieved at the transcriptional level. In addition, electrophoretic gel mobility shift assays indicated that the 104-bp region contained a 15-bp element, to which one or more A. oryzae cellular factors specifically bind. These results suggest that the 15-bp element between -195 nt and -181 nt includes the sequence essential for the transcription regulation of the A. oryzae enoA gene.

Role of ICAM-1 in the aggregation and adhesion of human alveolar macrophages in response to TNF-alpha and INF-gamma

Intracellular adhesion molecule-1 (ICAM-1)-mediated cell-cell adhesion is thought to play an important role at sites of inflammation. Recent evidence suggests that ICAM-1 surface expression on alveolar macrophages is increased in pulmonary sarcoidosis and that inflammatory granuloma formation is characterized by the aggregation of macrophages. The present study shows that ICAM-1 expression is significantly elevated on alveolar macrophages from patients with sarcoidosis in response to tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (INF-gamma) compared with healthy controls. Aggregation and adhesion were significantly increased in alveolar macrophages treated with TNF-alpha and INF-gamma, and significantly inhibited in those pretreated with a monoclonal antibody to ICAM-1. Similarly, aggregation and adhesion were inhibited in macrophages treated with heparin, which then exhibited a wide range of biological activities relevant to inflammation. These results suggested that the surface expression of ICAM-1 on alveolar macrophages in response to TNF-alpha and INF-gamma is important in mediating aggregation and adhesion. Additionally, heparin may be useful for developing novel therapeutic agents for fibrotic lung disease.

[CD34+ progenitor cell transplantation from HLA-mismatched donors to two patients with chronic active Epstein-Barr virus infection]

We report two boys with chronic active Epstein-Barr virus infection (CAEBV) refractory to conventional chemotherapy, who received HLA-mismatched allografts of CD34-positive progenitor cells from their fathers. One patient developed veno-occlusive disease (VOD) of the liver on day 18 after transplantation and died on day 26. The other patient received the allograft during partial remission. Although he suffered recurrent infections due to Streptococcus viridans, he is now doing well 23 months after transplantation. CAEBV refractory to chemotherapy is considered to be a fatal EBV-infected T/NK-cell lymphoproliferative disease, and our experiences suggest that CD34-positive progenitor cell transplantation for patients with CAEBV lacking HLA-matched donors may be a feasible and useful treatment. However, the timing of transplantation is considered to be critical, and should be performed when the patient is in good clinical condition.

Different onsets of oxidative damage to DNA and lipids in bone marrow and liver in rats given total body irradiation

We examined time-dependent changes in antioxidant vitamins and oxidative damage to DNA and lipids in the bone marrow, liver, and plasma of rats given total body irradiation (TBI) with X-rays at 3 Gy. The oxidative damage to DNA and lipids was evaluated by measuring increases of 8-hydroxydeoxyguanosine (8OHdG) in DNA and 4-hydroxy-2-nonenal (HNE), respectively. After the TBI, marked increases in 8OHdG and HNE were detected at 3 to 5 h in the bone marrow, while gradual increases in these parameters were detected after a few days in the liver. These changes in 8OHdG and HNE were well correlated within each tissue. In the bone marrow, levels of both vitamin C and vitamin E were decreased by the TBI; however, the changes in vitamin C were earlier and greater than those in vitamin E. In the liver, the level of vitamin C did not decrease, but that of vitamin E decreased due to the TBI. Changes in HNE, vitamin C, and vitamin E in the plasma were similar to those in the liver. Within each tissue, the time of decrease in antioxidants was almost the same as that of the increase in oxidative damage. An increase in total iron due to the TBI was also detected in these tissues. In particular, the total iron in the bone marrow was markedly increased at a few hours after the TBI, with a slight increase in transferrin and no increase in ferritin. Exposure studies performed on cells or isolated DNA showed that an increase in 8OHdG was detected immediately after irradiation at more than 100 Gy in bone marrow cells and at less than 10 Gy in isolated DNA, suggesting that an increase in 8OHdG is undetectable even in bone marrow immediately after the TBI at 3 Gy. These results indicate that the onset of oxidative damage to DNA and lipids was delayed after TBI at 3 Gy, that it was quite different in the bone marrow and the liver, and that an increase in iron and decrease in antioxidant vitamins were involved in the mechanism of oxidative damage.

Electrophoretic mobility shift scanning using an automated infrared DNA sequencer

Electrophoretic mobility shift assay (EMSA) is widely used in the study of sequence-specific DNA-binding proteins, including transcription factors and mismatch binding proteins. We have established a non-radioisotope-based protocol for EMSA that features an automated DNA sequencer with an infrared fluorescent dye (IRDye) detection unit. Our modification of the elec- trophoresis unit, which includes cooling the gel plates with a reduced well-to-read length, has made it possible to detect shifted bands within 1 h. Further, we have developed a rapid ligation-based method for generating IRDye-labeled probes with an approximately 60% cost reduction. This method has the advantages of real-time scanning, stability of labeled probes, and better safety associated with nonradioactive methods of detection. Analysis of a promoter from an industrially important filamentous fungus, Aspergillus oryzae, in a prototype experiment revealed that the method we describe has potential for use in systematic scanning and identification of the functionally important elements to which cellular factors bind in a sequence-specific manner.

A potential use of a synthetic retinoid TAC-101 as an orally active agent that blocks angiogenesis in liver metastases of human stomach cancer cells

TAC-101 (4-[3,5-bis(trimethylsilyl)benzamido]benzoic acid) is a novel, synthetic retinoid that is effective against liver metastases of human gastrointestinal cancer cells such as the human stomach carcinoma line AZ-521 in animal models, and is currently in use in phase I cancer trials. However, the mechanism of its antimetastatic action is still poorly understood. Tumor metastasis depends on angiogenesis, and various retinoids have been found to exhibit antiangiogenic activity. Based on these findings we here examined the antiangiogenic effects of TAC-101. Oral administration of TAC-101 (2-8 mg/kg/day) resulted in a drastic suppression of the AZ-521 cell-induced angiogenesis in a mouse dorsal air sac assay system, compared to the vehicle alone. Immunohistochemical analysis with antibody against the endothelial marker CD31 revealed a significant reduction in microvessel density in liver metastases from animals treated with TAC-101 (8 mg/kg p.o.), compared to liver metastases from the untreated control animals. The ability of TAC-101 (8 mg/kg p.o.) to prevent experimental liver metastasis of AZ-521 cells in athymic nude mice was comparable with that of the known angiogenesis inhibitor TNP-470 (30 mg/kg s.c.). TAC-101 also affected angiogenesis in chorioallantoic membranes and some functions of endothelial cells associated with angiogenesis, whereas the retinoid failed to suppress AZ-521 cell proliferation directly. These data suggest that the TAC-101 is an orally active antiangiogenic agent and that this antiangiogenic property may contribute to its efficacy against liver metastasis of human stomach cancer cells.

ERK and p38 MAPK, but not NF-kappaB, are critically involved in reactive oxygen species-mediated induction of IL-6 by angiotensin II in cardiac fibroblasts

We recently reported that angiotensin II (Ang II) induced IL-6 mRNA expression in cardiac fibroblasts, which played an important role in Ang II-induced cardiac hypertrophy in paracrine fashion. The present study investigated the regulatory mechanism of Ang II-induced IL-6 gene expression, focusing especially on reactive oxygen species (ROS)-mediated signaling in cardiac fibroblasts. Ang II increased intracellular ROS in cardiac fibroblasts, and the increase was completely inhibited by the AT-1 blocker candesartan and the NADH/NADPH oxidase inhibitor diphenyleneiodonium (DPI). We first confirmed that antioxidant N-acetylcysteine, superoxide scavenger Tiron, and DPI suppressed Ang II-induced IL-6 expression. Because we observed that exogenous H(2)O(2) also increased IL-6 mRNA, the signaling pathways downstream of Ang II and exogenous H(2)O(2) were compared. Ang II, as well as exogenous H(2)O(2), activated ERK, p38 MAPK, and JNK, which were significantly inhibited by N-acetylcysteine and DPI. In contrast with exogenous H(2)O(2), however, Ang II did not influence phosphorylation and degradation of IkappaB-alpha/beta or nuclear translocation of p65, nor did it increase NF-kappaB promoter activity. PD98059 and SB203580 inhibited Ang II-induced IL-6 expression. Truncation and mutational analysis of the IL-6 gene promoter showed that CRE was an important cis-element in Ang II-induced IL-6 gene expression. NF-kappaB-binding site was important for the basal expression of IL-6, but was not activated by Ang II. Ang II phosphorylated CREB through the ERK and p38 MAPK pathway in a ROS-sensitive manner. Collectively, these data indicated that Ang II stimulated ROS production via the AT1 receptor and NADH/NADPH oxidase, and that these ROS mediated activation of MAPKs, which culminated in IL-6 gene expression through a CRE-dependent, but not NF-kappaB-dependent, pathway in cardiac fibroblasts.

Modifying effects of propolis on MeIQx promotion of rat hepatocarcinogenesis and in a female rat two-stage carcinogenesis model after multiple carcinogen initiation

The modifying effects of the dietary administration of water- and ethanol-extracted propolis produced in Brazil (WB and EB, respectively) on 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) promotion of rat hepatocarcinogenesis were investigated in a medium-term liver bioassay system with use of male Fischer 344 rats. The number and area of glutathione S-transferase placental form (GST-P)-positive foci in rats given 0.5% WB were significantly increased compared with the group given MeIQx alone. Furthermore, the numbers of GST-P-positive foci were higher in rats given 0.1% WB or EB than in those given the basal diet alone. The modifying effects of propolis on other organs were also examined in female Fischer 344 rats given multiple carcinogens for initiation. Rats received water- and ethanol-extracted propolis produced in Brazil and Uruguay (WB, EB, WU, and EU, respectively) in the diet after exposure to three different carcinogens. The incidence of total mammary tumors was significantly lower in rats given EU than in the control group. These results indicate that a water extract of propolis exerts a cocarcinogenic effect on MeIQx hepatocarcinogenesis while promoting the effect at low dose in a two-stage hepatocarcinogenesis model. Moreover, they suggest that ethanol-extracted propolis may be an inhibitor of mammary gland carcinogenesis.

Erythromycin and clarithromycin modulation of growth factor-induced expression of heparanase mRNA on human lung cancer cells in vitro

Heparanase activity is correlated with the metastatic potential of several cancer cells and is a key enzyme in the breakdown of tissue barriers. It is also involved in the regulation of growth factor and cytokine activity. However, little is known about the factors that induce heparanase in cancer cells. We investigated the effect of three growth factors, platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF), on heparanase mRNA induction in lung cancer cells in vitro. In addition, we examined the effect of erythromycin (EM) and clarithromycin (CAM), which are 14-membered ring macrolide antibiotics that act as biological response modifiers, on the expression of heparanase mRNA induced by growth factors. PDGF, HGF and bFGF stimulated cell migration activity and enhanced the expression of heparanase mRNA in the human lung adenocarcinoma cell line A549. Via different mechanisms, EM and CAM modulate the induction by these factors of heparanase mRNA expression on A549 cells. EM also significantly suppressed A549 cell migration induced by PDGF and HGF, and CAM significantly suppressed A549cell migration induced by bFGF. The results suggest that the growth factors PDGF, HGF and bFGF are important inducers of heparanase in potentially invasive and metastatic cancer cells. The suppressive effect of heparanase mRNA expression by EM and CAM may have interestingtherapeutic applications in the prevention of metastasis.

Beef tallow, but not perilla or corn oil, promotion of rat prostate and intestinal carcinogenesis by 3,2'-dimethyl-4-aminobiphenyl

The modifying effects of three kinds of fat (corn oil, beef tallow or perilla oil, each at 20% in the diet) on F344 rat prostate carcinogenesis induced by 3,2'-dimethyl-4-aminobiphenyl (DMAB) were investigated. Non-invasive carcinomas of the ventral prostate were induced by DMAB alone and invasive carcinomas of the other prostate lobes and seminal vesicles by DMAB and testosterone propionate (TP). Eight groups of F344 rats were initiated with 50 mg / kg body weight of DMAB at 2-week intervals for the first 20 weeks, four also receiving TP, extended until week 60. The animals received basal chow powder diet or one of three high fat diets throughout the experiment (60 weeks). One further group served as a non-carcinogen-treated control maintained on basal chow powder diet. Beef tallow significantly increased the development of ventral prostate carcinomas with DMAB alone (from 15 to 45%, P < 0.05), while perilla oil reduced the incidence of prostatic intraepithelial neoplasia (PIN) in the ventral lobe of rats given DMA + TP (from 70 to 10%, P < 0.01), but not in those given DMAB alone. No other effects of high fats were observed regarding PIN or invasive cancers of the dorsolateral and anterior prostate or seminal vesicles. A satellite experiment demonstrated that all high fat diets for 4 weeks increased the 5-bromo-2-deoxyuridine (BrdU) labeling index of prostate epithelial cells, suggesting that a high fat intake, irrespective of the fatty acid composition, may accelerate cell kinetics in the prostate. Of the three high fat diets, beef tallow was also found to increase intestinal carcinogenesis. Thus, the present data revealed carcinogenesis in the prostate and intestine to be promoted by beef tallow.

In vitro effect of gelatins on murine cell proliferation

Porcine skin (PS) gelatin suppressed proliferation of a murine hepatic cell carcinoma cell line, MH134, a murine fibrosarcoma cell line, Meth A and a murine T cell lymphoma cell line, RL Male 1. The magnitude of suppression of the proliferation by cold water fish skin (CWFS) or bovine bone (BB) gelatin was lower than that by PS gelatin. On the other hand, BB gelatin stimulated proliferation of murine spleen cells. The magnitude of stimulation of the proliferation by CWFS gelatin was lower than that by BB gelatin. PS gelatin slightly suppressed proliferation of murine spleen cells. PS gelatin induced apoptosis but not necrosis of MH134 tumor cells. CWFS gelatin induced weaker apoptosis of the cells than PS gelatin. DNA histogram indicated that PS and CWFS gelatins acted on MH134 tumor cells to increase ratios of G2 + M-phase.

Pronounced inhibition by a natural anthocyanin, purple corn color, of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-associated colorectal carcinogenesis in male F344 rats pretreated with 1,2-dimethylhydrazine

The potential of purple corn color (PCC), a natural anthocyanin, to modify colorectal carcinogenesis was investigated in male F344/DuCrj rats, initially treated with 1,2-dimethylhydrazine (DMH), receiving 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in the diet. After DMH initiation, PCC was given at a dietary level of 5.0% in combination with 0.02% PhIP until week 36. No PCC-treatment-related changes in clinical signs, body weight and food consumption were found. Incidences and multiplicities of colorectal adenomas and carcinomas in rats initiated with DMH were clearly increased by PhIP. In contrast, lesion development was suppressed by PCC administration. Furthermore, in the non-DMH initiation groups, induction of aberrant crypt foci by PhIP tended to be decreased by the PCC supplementation. The results thus demonstrate that while PhIP clearly exerts promoting effects on DMH-induced colorectal carcinogenesis, these can be reduced by 5.0% PCC in the diet, under the present experimental conditions.

Staging of palpable T1-2 invasive breast cancer with helical CT

BACKGROUND

The purpose of this study was to evaluate the accuracy of contrast-enhanced high resolution helical computed tomography (CT) for assessing locoregional staging of palpable T1-2 invasive breast cancer.

METHODS

Helical CT studies of 156 lesions from 156 patients with invasive breast cancer before breast-conserving surgery were examined. A lesion was defined as positive if focal enhancement was detected by CT within 100 seconds after contrast material administration. After resection, tumors were histopathologically mapped and comparison made with the extent of contrast enhancement.

RESULTS

Helical CT enabled detection of all 156 index tumors. CT enabled detection of 28 of 43 multifocal lesions (65%) and five of five multicentric lesions (100%). In 24 of 33 lesions (73%), CT revealed additional cancers not seen on mammography. The extent of tumor significantly correlated with CT measurements (r=0.76, p<0.0001).

CONCLUSION

Helical CT of the breast is an accurate preoperative imaging modality for assessing the locoregional staging of T1-2 invasive breast cancer.

Ring closure of carbon nanotubes

Lightly etched single-walled carbon nanotubes are chemically reacted to form rings. The rings appear to be fully closed as opposed to open coils, as ring-opening reactions did not change the structure of the observed rings. The average diameter of the rings was 540 nanometers with a narrow size distribution. The nanotubes in solution were modeled as wormlike polymer chains, yielding a persistence length of 800 nanometers. Nanotubes shorter than this length behave stiffly and stay nearly straight in solution. However, nanotubes longer than the Kuhn segment length of 1600 nanometers undergo considerable thermal fluctuation, suggesting a greater flexibility of these materials than is generally assumed.

Organ dependent enhancement of rat 3,2'-dimethyl-4-aminobiphenyl (DMAB) carcinogenesis by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP): positive effects on the intestine but not the prostate

In order to evaluate tumor enhancing effects of the heterocyclic carcinogen, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), doses of 100 and 300 p.p.m. PhIP were given for 40 weeks to male F344 rats, which initially received 3,2'-dimethyl-4-aminobiphenyl (DMAB). DMAB shows a similar carcinogenic organ spectrum to that of PhIP, including the prostate and colon. PhIP alone at a dose of 300 p.p.m. resulted in the development of prostate and intestine cancers. Furthermore, among the DMAB-treated group, enhancement of intestinal carcinogenesis by 300 p.p.m. PhIP was observed. However, no prostate enhancement was demonstrated in the DMAB + PhIP group. Since PhIP-DNA adduct formation in the prostate epithelial cells in a satellite experiment was not affected by pre-treatment with DMAB, it is speculated that the contradictory findings between the intestine and prostate may be due to the specific biological effects of PhIP. Taking into account previous data, that PhIP clearly enhanced rat 1,2-dimethylhydrazine-initiated colon tumorigenesis, the potential of PhIP to enhance colon carcinogenesis may be initiator dependent.

Postoperative chemoendocrine therapy for women with node-positive stage II breast cancer with combined cyclophosphamide, tamoxifen, and 1-hexylcarbamoyl-5-fluorouracil

OBJECTIVE

To find out whether the addition of 1-hexylcarbamoyl-5-fluorouracil to a postoperative regimen of oral cyclophosphamide and tamoxifen improved the prognosis of carcinoma of the breast.

DESIGN

Randomised controlled clinical trial.

SETTING

127 Institutions in Japan.

SUBJECTS

785 Patients with stage II carcinoma (palpable axillary nodes) who had total mastectomy and axillary clearance.

INTERVENTIONS

The control group were given oral cyclophosphamide 50 mg/day and tamoxifen 20 mg/day for 2 years; the experimental group were given these drugs plus 1-hexylcarbamoyl-5-fluorouracil 300 mg/day for 2 years.

RESULTS

There was no survival advantage (and more toxicity) in the experimental group, except in a subgroup with 1-3 axillary nodes involved.

CONCLUSION

The advantage of triple chemotherapy in the subgroup must be substantiated by a new randomised trial confined to patients with 1-3 axillary nodes involved.

Angiogenesis and mast cells in non-Hodgkin's lymphoma: a strong correlation in angioimmunoblastic T-cell lymphoma

Mast cells are likely to play a role in angiogenesis under pathological conditions. Solid tumor growth is dependent on angiogenesis, but the influence of mast cells on angiogenesis in non-Hodgkin's lymphoma, (NHL) is not clear. We investigated mast cell number and vessel count in 61 cases of NHL. We also evaluated expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), both important cytokines for angiogenesis. The number of mast cells was greater in T-cell lymphomas than in B-cell lymphomas. Of the T-cell lymphomas, the greatest number of mast cells was observed in the angioimmunoblastic T-cell lymphoma (AIL). In all NHLs, significant correlation was found between vessel count and the number of mast cells (p < 0.0001) and between vessel count and the number of VEGF-expressing cells (p < 0.05) but not between vessel count and bFGF-expressing cells. Strong correlation was detected between the number of mast cells and the number of VEGF-expressing cells (p < 0.0001) in all NHLs. Double fluorescence staining of VEGF mRNA and mast cell tryptase revealed that mast cells expressed VEGF mRNA. Our data suggest that mast cells play a very important role in angiogenesis by expressing VEGF in NHL, especially in AIL.

A possible role for BDNF, NT-4 and TrkB in the spinal cord and muscle of rat subjected to mechanical overload, bupivacaine injection and axotomy

Neurotrophins play a crucial role in the regulation of survival and the maintenance of specific functions for various populations of neurons. Neurotrophin-4 (NT-4) is most abundant in skeletal muscle, and is thought to promote sciatic nerve sprouting, inhibit agrin-induced acetylcholine receptor (AChR) clustering, evoke postsynaptic potentiation and induce mitochondrial proliferation. Using Western blot analysis, immunoprecipitation and immunohistochemistry, we investigated the distribution of NT-4 in slow- and fast-type muscles. We also tested the adaptive response of this protein in the mechanically overloaded muscle, in the regenerating muscle following bupivacaine injection and in the denervated muscle. Additionally, we investigated whether TrkB phosphorylation in the spinal cord and in the sciatic nerve occurs through the interaction with BDNF or NT-4 when the innervating muscle is damaged. Markedly more NT-4 was expressed in fast-type muscles compared with the slow types. TrkB protein was more frequently observed around the edge of myofibers (neuromuscular junction) of the soleus muscle compared with the gastrocnemius muscle. TrkB tyrosine phosphorylation occurred in the spinal cord but not in the sciatic nerve 24 h after bupivacaine injection of the innervating muscle. At the same time, the amount of TrkB co-precipitating with BDNF was markedly increased in the spinal cord. A rapid activation of TrkB (1-8 h) was also observed in the spinal cord after axotomy,while the amount of TrkB co-precipitating with NT-4 was markedly lower after axotomy. These results indicate that NT-4 is preferentially distributed in fast-type muscles. Furthermore, by interacting with BDNF and NT-4, the TrkB in the spinal cord may be important for the survival of motoneurons and outgrowth of injured peripheral axons following muscle damage.

Significantly higher activity of a cytoplasmic hammerhead ribozyme than a corresponding nuclear counterpart: engineered tRNAs with an extended 3' end can be exported efficiently and specifically to the cytoplasm in mammalian cells

Hammerhead ribozymes were expressed under the control of similar tRNA promoters, localizing transcripts either in the cytoplasm or the nucleus. The tRNA(Val)-driven ribozyme (tRNA-Rz; tRNA with extra sequences at the 3' end) that has been used in our ribozyme studies was exported efficiently into the cytoplasm and ribozyme activity was detected only in the cytoplasmic fraction. Both ends of the transported tRNA-Rz were characterized comprehensively and the results confirmed that tRNA-Rz had unprocessed 5' and 3' ends. Furthermore, it was also demonstrated that the activity of the exported ribozyme was significantly higher than that of the ribozyme which remained in the nucleus. We suggest that it is possible to engineer tRNA-Rz, which can be exported to the cytoplasm based on an understanding of secondary structures, and then tRNA-driven ribozymes may be co-localized with their target mRNAs in the cytoplasm of mammalian cells.

Longitudinal study of quality of life in people with advanced Alzheimer's disease

The authors examined three indicators of health-related quality of life in people with advanced Alzheimer's disease ([AD]; N=150): confinement to home, null activity, and null positive affect, as reported by patient proxies. Dementia severity predicted time-to-onset for all three disease milestones in models that controlled for sociodemographic indicators, nursing home status, and death in the follow-up period. Patients whose dementia worsened over follow-up were more likely to reach each milestone. These outcomes represent key milestones in the care of patients; they are sensitive to disease progression, and they are likely to be useful for studying treatment in advanced AD.

Peroxisomes exist in growth cones and move anterogradely and retrogradely in neurites of PC12D cells

Localization and movement of peroxisomes have been investigated in neurites of a subline of PC12 pheochromocytoma cells (PC12D cells). The cells were transfected with a construct encoding the green fluorescent protein and bearing the C-terminal peroxisomal targeting signal 1 SKL motif (-Ser-Lys-Leu-COOH). Peroxisomes were detected as green punctate fluorescent signals. Many peroxisomes were observed in neurites of PC12D cells, especially in neural terminal-like structures, growth cones, varicosities, and branch points. Growth cones containing many peroxisomes were active, since they extended several long filopodias. Existence of peroxisomes in growth cones and neuronal terminal-like structures suggests that peroxisomes might have some role in neuronal extension and nerve terminal functioning. Peroxisomal motility was analyzed by time-lapse imaging using a fluorescence microscope at 25 degrees C. Peroxisomes were transported bidirectionally in neurites, i.e., through anterograde and retrograde transport. This result suggests that peroxisomes move to growth cones and neural terminals from the PC12D cell body, play some role in these parts, and go back to cell body.

Radicicol and geldanamycin prevent neurotoxic effects of anti-cancer drugs on cultured embryonic sensory neurons

Cultured dorsal root ganglion (DRG) neurons from chick embryos were extremely susceptible to the antineoplastic drugs, cisplatin, vincristine and taxol even in the presence of saturating levels of the neurotrophins, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3). We previously reported that a low concentration of radicicol enhanced the survival and neurite outgrowth of the embryonic sensory and sympathetic neurons, although the effect was decreased at higher doses. The neurotoxic effects of these anti-cancer drugs were completely prevented by the addition of radicicol (20 nM) to the cultures. Recent studies showed that the major intracellular target of radicicol and geldanamycin is the heat shock protein 90 (HSP90) chaperone, interfering with its function. In this study, geldanamycin at low doses (about 2 nM) also appeared to be neurotrophic on DRG neurons in the presence or absence of neurotrophins, but higher doses of geldanamycin (> 5 nM) had severe cytotoxic effects on neurons. Higher doses of radicicol (500 nM), however, still promoted neurites and prevented apoptosis of the isolated DRG neurons in the absence of neurotrophins. Geldanamycin at low doses was also found to be neuroprotective against anti-cancer drugs as shown with radicicol. Treatment of neurons with optimal doses of geldanamycin and radicicol together was cytotoxic instead of neurotrophic. These two antibiotics may share a common target to provide a trophic effect to the cultured neurons. However, different cellular effects of the two antibiotics are not easily explained. It is presumed that the novel activity might be mediated via suppression of HSP90 function, although the possibility that limited doses of these antibiotics interact with specific target molecule(s) other than HSP90 and suppress apoptosis cannot be ruled out. Present results indicate that radicicol has therapeutic potential for neurodegenerative diseases, especially for anti-cancer drug-induced sensory neuropathy.

Simultaneous determination of twelve tea catechins by high-performance liquid chromatography with electrochemical detection

A high-performance liquid chromatographic method with electrochemical detection was developed for the determination of twelve tea catechins including four major catechins: epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG); four of their epimers at the C-2 position, C, GC, CG and GCG; and four methylated catechin derivatives, epigallocatechin-3-O-(3-O-methyl)gallate, gallocatechin-3-O-(3-O-methyl)gallate, epigallocatechin-3-O-(4-O-methyl)gallate and epicatechin-3-O-(3-O-methyl)gallate. These catechins were separated on an ODS C18 reversed-phase column by isocratic elution with 0.1 M NaH2PO4 buffer (pH 2.5)-acetonitrile (87:13) containing 0.1 mM EDTA.2Na. The detection limits (S/N = 3) of these catechins were approximately 10-40 pmol ml-1 at an applied voltage of 600 mV. Extracting these catechins from tea leaf powder with H2O-acetonitrile (1:1) at 30 degrees C for 40 min inhibited the epimerization at C-2 significantly from these epicatechins compared to extraction with hot water at 90 degrees C. This analytical method is sensitive to and appropriate for the simultaneous determination of various biologically active catechins in green tea.

[A case of bronchioloalveolar cell carcinoma with bilateral diffuse interstitial infiltrative shadow during the treatment of Takatsuki's disease]

A 54-year old man treated with Takatsuki's disease was referred to us complaining of cough and excessive sputum. A chest roentgenogram showed bilateral diffuse interstitial infiltrative shadow. Chest CT showed banding shadows around the bronchioles and lobule-septum thickening in the right middle and both lower lung fields, and many small nodules in both lower lung fields. The histological diagnosis was adenocarcinoma replaced with one layer of bronchiolar epithelium, and partly bronchiolo-alveolar carcinoma. The patient received 3 courses of combination chemotherapy with docetaxel and cisplatin. After chemotherapy, the chest CT showed no change. The clinicopathological characteristics of this rare case included adenocarcinoma mixed with bronchioloalveolar carcinoma, in which radiography showed bilateral diffuse interstitial infiltrative shadow.

Comparison of the expression of cell surface poly-N-acetyllactosamine-type oligosaccharides in PC12 cells with those in its variant PC12D

To explore the biological role of carbohydrate chains in the process of nerve cell differentiation, we carried out a characterization of the carbohydrate structure of glycoproteins by comparing conventional PC12 cells with variant cells (PC12D). In vitro metabolic labeling of cells with either [(3)H] glucosamine or [(3)H] threonine, together with tomato lectin staining, revealed that nerve growth factor (NGF) stimulation caused a decrease in the poly-N-acetyllactosamine synthesis of high-molecular-weight glycopeptides from PC12 cells. By comparison, the amount of glycopeptides with poly-N-acetyllactosamine from PC12D cells was already significantly low and it was not changed by NGF stimulation. By assaying the glycosyltransferases that participate in poly-N-acetyllactosamine synthesis, the decrease in the amount of the poly-N-acetyllactosamine in PC12D cells as well as NGF-stimulated PC12 cells could be accounted for by a reduction in the activity of poly-N-acetyllactosamine extension enzyme (GnT-i), because the amount of poly-N-acetyllactosamine in both cells precisely correlated with changes in GnT-i activity, whereas the activities of N-acetylglucosaminyltransferase V (GnT-V) and beta 1-4 galactosyltransferase remained unchanged. These results demonstrate that the decrease in poly-N-acetyllactosamine synthesis in PC12 cells occurred prior to neurite formation, whereas PC12D cells were insensitive to this effect. Next, we showed that GnT-i but not GnT-V catalyzed a rate-limiting reaction in the expression of poly-N-acetyllactosamine chains, especially in pheochromocytoma.