Physician's attitudes towards disclosure of cancer diagnosis to elderly patients: a report from Tokyo, Japan

Physicians' attitudes towards the disclosure of a cancer diagnosis to 114 consecutive patients (age range, 65-93 years; median 78 years) admitted to the Tokyo Metropolitan Tama Geriatric Hospital from April 1994 to May 1995 were analyzed utilizing a questionnaire administered to the attending physicians. Eighty-seven patients (76%) had been informed of their diagnosis before the initiation of cancer treatment, while 27 patients (24%) were not told. 'To carry out the treatment under patient's understanding' and 'consideration for patient's quality of life' were the major reasons for diagnosis disclosure, while 'lack of patient's ability to understand the information' and 'family's wish that the patient not be informed of the truth' were the major reasons for non-disclosure. Dementia, deteriorated performance status, and non-curability were major factors related to non-disclosure. Even with decisional ability, 15% of patients were not told their cancer diagnosis because wishes of their families were preferred. The current results suggest that telling cancer diagnosis to the elderly patients will not yield negative attitude of the patients and that there is no rationale for physicians to hesitate to disclose cancer diagnosis merely because of patient's high age.

Suppression of spermatogenesis in ipsilateral and contralateral testicular tissues in patients with seminoma by human chorionic gonadotropin beta subunit

OBJECTIVES

The pathologic complexity of the testicular tumor makes it difficult to demonstrate exactly the relationship between the impaired spermatogenesis in patients with a testicular tumor and the serum level of the human chorionic gonadotropin beta subunit (beta-hCG). Therefore, we performed quantitative evaluation of spermatogenesis in ipsilateral and contralateral testicular tissues of seminoma to simplify the relation pathologically and endocrinologically and to demonstrate the exact correlation between spermatogenesis and serum beta-hCG levels.

METHODS

Fifty-three biopsy specimens from ipsilateral and contralateral testicular tissues of seminoma were analyzed histologically. The quantitative evaluation of spermatogenesis was performed by the mean Johnsen's score count (MJSC). Beta-hCG expression in seminoma was examined immunohistochemically. Serum beta-hCG, testosterone, estradiol, luteinizing hormone, and follicle-stimulating hormone levels were analyzed before orchiectomy.

RESULTS

A significant linear relationship (r = -0.82; P <0.005) was found between the serum level of beta-hCG and the MJSC in contralateral testicular tissues but not in ipsilateral ones, although the suppression of spermatogenesis was observed in both sides without suppression of luteinizing hormone and/or follicle-stimulating hormone production.

CONCLUSIONS

A clearcut fall in the MJSC with an associated rise in the serum level of beta-hCG was demonstrated in the contralateral testicular tissues but not in the ipsilateral ones of seminoma. It seems most likely that serum beta-hCG suppresses spermatogenesis in both ipsilateral and contralateral testicular tissues without the suppression occurring through the hypothalamus-pituitary-gonadal system, and also that some less well recognized factors affect spermatogenesis, making the relation between serum beta-hCG and MJSC obscure in ipsilateral testicular tissues.

Parotid masses: prediction of malignancy using magnetization transfer and MR imaging findings

OBJECTIVE

We determined the most accurate criteria for predicting malignancy of masses in the parotid gland using magnetization transfer ratios.

SUBJECTS AND METHODS

Lesion-to-muscle magnetization transfer ratios obtained with a spoiled gradient-recalled acquisition in a steady state sequence with a 1-kHz off-resonance pulse were measured in 72 parotid masses (52 benign lesions, 20 malignant tumors). Various MR imaging findings and lesion-to-muscle magnetization transfer ratios were simultaneously assessed using a logistic model to determine the useful factors for predicting malignancy. We also studied the clinical usage of magnetization transfer ratios.

RESULTS

Of the MR imaging findings, poorly defined margins showed the highest accuracy, 81%, with 60% sensitivity and 88% specificity. Of the lesion-to-muscle magnetization transfer ratios, a ratio of greater than 0.71 was most accurate (85%), with 90% sensitivity and 83% specificity. All four recurrent tumors and 10 (91%) of 11 secondary tumors were correctly diagnosed using the magnetization transfer ratio analysis. The logistic model revealed that the margin characteristics (p = 0.084) and lesion-to-muscle magnetization transfer ratios (p < 0.001) were statistically significant predictors for malignancy. A combined criteria of poorly defined margins and a lesion-to-muscle magnetization transfer ratio of greater than 0.71 raised the accuracy to 86% and specificity to 96%, but the sensitivity decreased to 60%.

CONCLUSION

A combination of MR imaging findings and lesion-to-muscle magnetization transfer ratios was the most accurate predictor of malignancy.

High-resolution CT analysis of small peripheral lung adenocarcinomas revealed on screening helical CT

OBJECTIVE

The purpose of this study was to determine the correlation between high-resolution CT morphologic features of small peripheral lung adenocarcinomas and tumor growth patterns.

MATERIALS AND METHODS

We examined high-resolution CT morphologic features of 59 small, surgically resected peripheral lung adenocarcinomas (diameter, 6-20 mm) that were detected on screening for lung cancer using low-dose helical CT. Among these adenocarcinomas, 14 (24%) were visible and 45 (76%) were invisible on conventional chest radiography. The correlation between high-resolution CT morphologic features and tumor growth patterns was analyzed.

RESULTS

Sixteen (94%) of 17 type A (Noguchi's classification) adenocarcinomas appeared as nodules of pure ground-glass attenuation (high-resolution CT type I). Ten (71%) of 14 type B tumors appeared as heterogeneous, low-attenuation nodules (type II). Seven (29%) of 24 type C tumors appeared as nodules with ground-glass attenuation in the periphery and a high-density central zone (type III), and 12 (50%) of 24 type C tumors appeared as homogeneous nodules with soft-tissue density (type IV). Among tumors with a replacement growth pattern, the size and CT values of type C tumors were larger than those of type A or type B tumors (p < 0.05), whereas the percentage of ground-glass attenuation and retained air space in type C tumors was smaller than those in type A or type B tumors (p < 0.01). All (100%) four type D tumors appeared to be homogeneous nodules with soft-tissue density (type IV).

CONCLUSION

Small peripheral lung adenocarcinomas shown on CT exhibit four high-resolution CT patterns that corresponded to the histopathologic findings of different tumor growth patterns.

Pituitary follistatin and activin gene expression, and the testicular regulation of FSH in the adult Rhesus monkey (Macaca mulatta)

In rats, FSHbeta gene expression and FSH secretion are increased and decreased, respectively, by pituitary activin and follistatin. Because little information is available on the paracrine control of FSH secretion in the primate, follistatin and activin/inhibin beta(B) messenger RNA (mRNA) levels were measured in pituitaries of adult male rhesus monkeys 6 weeks after castration or sham surgery (n = 5/group). Follistatin mRNA was determined by quantitative RT-PCR assay using oligonucleotide primers designed to span exons 3-5 of the human follistatin gene. Activin/inhibin beta(B) mRNA levels were measured by ribonuclease protection. Orchidectomy resulted in a 100-fold increase in plasma FSH concentrations and a 60-fold rise in those of LH. In castrated monkeys, levels of mRNA encoding FSHbeta, LHbeta, alpha- subunit, and GnRH receptor (GnRH-R) were increased 21-, 2.1-, 1.7-, and 1.7-fold, respectively (P < 0.01). Levels of pituitary follistatin and activin/inhibin beta(B) mRNAs, however, were similar in castrated and intact animals. These data suggest that the paracrine control of FSH secretion in the male differs substantially in primates and rodents. Specifically, the relatively greater postcastration rise in FSHbeta gene expression and FSH secretion in the adult male monkey may result because in this species pituitary follistatin gene expression does not increase after orchidectomy, as it does in the rat.

Spontaneous extensive necrosis in non-Hodgkin lymphoma: prevalence and clinical significance

PURPOSE

We studied the prevalence of spontaneous extensive necrosis in the nodes of patients with non-Hodgkin lymphomas and assessed the clinical significance of this finding.

METHOD

CT and MRI performed before initiation of radiation or chemotherapy were reviewed in 60 consecutive patients with non-Hodgkin lymphomas to evaluate the presence or absence of spontaneous extensive necrosis in the lymphomatous nodes. The results were correlated with histopathologic grading, stages of lymphomas, maximal axial diameters of the lesions, International Prognostic Index (IPI), age, and serum lactate dehydrogenase (LDH) levels. We then performed Kaplan-Meier analysis of disease-free survival using each factor.

RESULTS

Extensive necrotic nodes that appeared as rim-enhanced masses on enhanced CT or MR images were found in 15 patients (25%), of whom 10 patients had pathologic verification. The patients with necrosis had significantly higher stages (Stage II or higher), greater IPI (IPI of > or = 2), and higher serum LDH levels than those without necrosis (p = 0.001, p = 0.005, and p = 0.005, respectively). With the Kaplan-Meier method, a statistically significant difference was noted for serum LDH levels (p = 0.015) and IPI (p = 0.021) but not for extensive necrosis (p = 0.600).

CONCLUSION

Spontaneous extensive necrosis in lymphomatous nodes is not a rare event. This finding may have a prognostic significance for patients with non-Hodgkin lymphomas.

Hepatic necrosis with cholestasis induced by long-term voglibose administration

A 76-year-old woman admitted to our hospital for jaundice had been treated for diabetes mellitus with insulin for 9 years and voglibose had been added for the 39 months preceding admission. Elevated serum bilirubin and transaminase concentration began to normalize with initiation of corticosteroid treatment 1 week after discontinuation of voglibose. In the in vitro testing of the patient's peripheral blood, lymphocytes showed stimulation by voglibose. In dramatic contrast to an initial liver biopsy specimen that demonstrated cholestasis with submassive and zonal necrosis, the follow-up specimen was normal 1 year later. We believe that patients treated with voglibose should be monitored long-term with monthly determinations of transaminases and bilirubin in serum.

Enhanced gene transfection in macrophages using mannosylated cationic liposome-polyethylenimine-plasmid DNA complexes

We have previously reported that plasmid DNA and cholesten-5-yloxy-N-(4-[(1-imino-2-beta-D-thiomannosylethyl)amino]butyl) formamide(Man-C4-Chol)/dioleoylphosphatidylethano-lamine(DOPE)(6:4) liposome complexes (DNA/Man-complexes) exhibit efficient gene transfection in macrophages via mannose receptor-mediated endocytosis. To further enhance gene transfetion, polyethylenimine (PEI) was incorporated into this liposome complex (DNA/Man-PEI-complexes), noticing a pH-buffering capacity in endosomes and DNA-condensing activity of PEI. In mouse peritoneal macrophages, the uptake and transfection activity of DNA/Man-PEI-complexes were 2-times and 6-times higher than those of DNA/Man-complexes, respectively. Furthermore, the presence of 1 mg/ml mannan significantly inhibited both the uptake and transfection efficiency of DNA/Man-PEI-complexes. These results suggested that the newly developed multifunctional DNA/Man-PEI-complexes exhibit highly improved gene transfection in macrophages via mannose receptor-mediated endocytosis.

Intracerebroventricular injection of agouti-related protein attenuates the anorexigenic effect of alpha-melanocyte stimulating hormone in neonatal chicks

It is well known that alpha-melanocyte stimulating hormone (alpha-MSH) inhibits feeding via melanocortin receptor-4 (MC4R) in the mammalian brain. The anorexigenic effect of alpha-MSH is attenuated by agouti-related protein (AGRP), an antagonist for MC4R. Present studies were carried out to clarify whether human AGRP (86-132) antagonizes the anorexigenic effect of alpha-MSH in broiler chicks. Intracerebroventricular injection of AGRP attenuated the anorexigenic effect of alpha-MSH. Furthermore, AGRP stimulated food intake of layer-type chicks under an ad libitum feeding condition but not broiler chicks, suggesting that the orexigenic effect of AGRP is different between two breeds. These also imply that the extent of the anorexigenic effect of endogenous alpha-MSH is different among two breeds. This may be a part of the difference in food intake between two breeds.

Tumor suppressor protein VHL is induced at high cell density and mediates contact inhibition of cell growth

In spite of the general recognition of von Hippel-Lindau (VHL) as a tumor suppressor gene, the physiological and pathological importance of VHL protein in cell growth regulation and tumorigenesis remains unclear. Here we show that in normal human renal proximal tubule epithelial cells (RPTEC), the steady-state amount of VHL protein is strictly regulated by cell density. The cellular VHL content is more than 100-fold higher in dense cultures than in sparse cultures. The increase in VHL protein at high cell density was also observed for NIH3T3 fibroblasts, suggesting the generality of the phenomenon. The growth rates of renal cell carcinoma cells lacking an intact VHL gene and their derivatives with wild-type or mutant VHL expression vector do not differ significantly when they are growing in log-phase. Importantly, however, there is a difference when they reach confluency: cells lacking wild-type VHL grew continuously, while cells expressing exogenous VHL protein showed relatively limited cell growth. Using an ecdysone-inducible VHL expressing cell line, we also show that the growth inhibition at high cell density can be released by attenuating the VHL expression. Taken together, we propose that VHL protein functions as a growth suppressor at high cell density, and this might be the basis of the tumor suppressor function of VHL.

Regulation of vascular endothelial growth factor transcription by endothelial PAS domain protein 1 (EPAS1) and possible involvement of EPAS1 in the angiogenesis of renal cell carcinoma

BACKGROUND

Endothelial PAS domain protein 1 (EPAS1) is a basic helix-loop-helix/PAS domain transcription factor that expressed most abundantly in highly vascularized organs. The authors examined the effect of transfection of EPAS1 cDNA on the endogenous expression of vascular endothelial growth factor (VEGF) in the 293 Tet-Off cell line and the possible involvement of EPAS1 in the angiogenesis of renal cell carcinoma (RCC).

METHODS

Complete cDNA of EPAS1 was cloned and transfected to cells from the 293 Tet-Off fetal kidney cell line, in which the expression of EPAS1 can be inhibited by doxycycline. The subsequent changes in expression pattern of VEGF and transferrin receptor (TfR), a target gene of hypoxia-inducible factor 1alpha (HIF-1alpha), were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay. In addition, expression of EPAS1, HIF-1alpha, and VEGF were analyzed by semiquantitative RT-PCR in five RCC cell lines and in 13 RCC tissue samples. In situ hybridization was performed on 7 of the 13 RCC tissue samples.

RESULTS

Endogenous VEGF was increased significantly by the introduction of EPAS1 cDNA at both the mRNA level and the protein level. With the inhibition of EPAS1 by doxycycline treatment, the expression of VEGF was significantly decreased accordingly, whereas the expression of TfR was not affected. EPAS1 was detected in all of the RCC cell lines examined. In RCC tissue samples, EPAS1 mRNA and VEGF mRNA were increased significantly in tumor tissues compared with normal adjacent kidney tissues. In situ hybridization showed that EPAS1 and VEGF were coexpressed topographically in tumor tissues.

CONCLUSIONS

These results suggest that endogenous VEGF can be up-regulated transcriptionally by EPAS1, and EPAS1 may be involved in the angiogenesis of RCC.

Presence of an SAR-like sequence in junction regions between an introduced transgene and genomic DNA of cultured tobacco cells: its effect on transformation frequency

A 12.5-kb DNA fragment with junction regions between the transgene and genomic DNA was cloned from a transgenic tobacco cell line obtained by microprojectile bombardment of plasmid pCaMVNEO. Nucleotide sequence analysis of the fragment (DDBJ accession no. D84238) showed that it carried a 7.7-kb core sequence (concatemer of a complete pCaMVNEO and a partial pCaMVNEO) and two identical 1.3-kb junction sequences that flanked both the 5' and 3' ends of the core sequence and had inverted orientations. These sequences had topoisomerase II (Topo II) cleavage sites and adenine and thimine-rich sequences known to be specific to nuclear scaffold-attachment regions (SARs). An in vitro binding assay showed that a 507-bp fragment (designated TJ1) from the 1.3-kb sequence had the ability to bind to nuclear scaffold preparations of cultured tobacco cells, confirmation that the 1.3-kb sequence is an SAR. Insertion of TJ1 at the 5' and 3' sides of the expression cassette for the npt II gene increased transformant yields 5- to 10-fold and the NPT II enzyme activity per copy of the gene 5-fold. TJ1 enhances the integration or expression of the transgene, or both. Clearly, TJ1 is very useful for producing transgenic plants. This is the first report on an SAR-like sequence that is located in the transgene locus and enhances transformation efficiency in eukaryotic cells. The possible role of TJ1-SAR in the molecular evolution of plant genome is discussed.

Atypical adenomatous hyperplasia of the lung: correlation between high-resolution CT findings and histopathologic features

We describe herein the CT features of atypical adenomatous hyperplasia (AAH) of the lung and its histopathological characteristics. Among 17,919 individuals screened for lung cancer by CT scanning, ten AAH nodules were detected in nine asymptomatic subjects. On high-resolution CT, the lesions measured from 6 x 6 mm to 15 x 17 mm and their CT number ranged from -500 to -760 HU. The AAHs appeared as round nodules with smooth and distinct borders and showed a ground-glass opacity. Plain chest radiographs failed to identify all lesions. Histopathologically, AAH lesions showed atypical epithelial cell proliferation along slightly thickened alveolar septa. Whereas it is often easy to differentiate these nodules from inflammatory and benign lung lesions, histopathological examination remains at present the only method to differentiate AAH from lung cancers.

Regulation of vascular endothelial growth factor transcription by endothelial PAS domain protein 1 (EPAS1) and possible involvement of EPAS1 in the angiogenesis of renal cell carcinoma

BACKGROUND

Endothelial PAS domain protein 1 (EPAS1) is a basic helix-loop-helix/PAS domain transcription factor that expressed most abundantly in highly vascularized organs. The authors examined the effect of transfection of EPAS1 cDNA on the endogenous expression of vascular endothelial growth factor (VEGF) in the 293 Tet-Off cell line and the possible involvement of EPAS1 in the angiogenesis of renal cell carcinoma (RCC).

METHODS

Complete cDNA of EPAS1 was cloned and transfected to cells from the 293 Tet-Off fetal kidney cell line, in which the expression of EPAS1 can be inhibited by doxycycline. The subsequent changes in expression pattern of VEGF and transferrin receptor (TfR), a target gene of hypoxia-inducible factor 1alpha (HIF-1alpha), were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay. In addition, expression of EPAS1, HIF-1alpha, and VEGF were analyzed by semiquantitative RT-PCR in five RCC cell lines and in 13 RCC tissue samples. In situ hybridization was performed on 7 of the 13 RCC tissue samples.

RESULTS

Endogenous VEGF was increased significantly by the introduction of EPAS1 cDNA at both the mRNA level and the protein level. With the inhibition of EPAS1 by doxycycline treatment, the expression of VEGF was significantly decreased accordingly, whereas the expression of TfR was not affected. EPAS1 was detected in all of the RCC cell lines examined. In RCC tissue samples, EPAS1 mRNA and VEGF mRNA were increased significantly in tumor tissues compared with normal adjacent kidney tissues. In situ hybridization showed that EPAS1 and VEGF were coexpressed topographically in tumor tissues.

CONCLUSIONS

These results suggest that endogenous VEGF can be up-regulated transcriptionally by EPAS1, and EPAS1 may be involved in the angiogenesis of RCC.

[Study of neoadjuvant chemotherapy for invasive bladder cancer with MEC (methotrexate, epirubicin, cisplatin) therapy]

Eighteen patients with locally invasive bladder cancer were treated with 1 or 2 cycles of neoadjuvant chemotherapy consisting of methotrexate, epirubicin and cisplatin (MEC). All patients underwent radical cystectomy and pelvic lymph node dissection. Down-staging was observed in twelve (complete pathological response in 3 and partial pathological response in 9) patients (response rate were 67%). Four of the 18 patients died of disease and all of them had not achieved down-staging. Multivariate analysis revealed nodal status to be the only independent predictor. With regard to side effects, gastrointestinal symptoms and myelo-suppression were observed in almost all patients. Thrombocytopenia was observed in 13 patients (72%) including 7 patients who showed symptoms over grade 3. Gastro-intestinal symptoms and leukocytopenia disappeared with granisetron and granulocyte colony stimulating factor. There were no treatment-related deaths in this study. These results indicate that MEC therapy was safely performed and showed a high response rate in patients with locally invasive bladder cancer.

Involvement of serum mannan binding proteins and mannose receptors in uptake of mannosylated liposomes by macrophages

The roles of serum mannan binding protein (MBP) and the mannose receptor in the cellular uptake of mannosylated liposomes (Man-liposomes) by macrophages were studied. Man-liposomes were prepared by incorporating cholesten-5-yloxy-N-(4-((1-imino-2-beta-D-thiomannosylethyl)amino)butyl)formamide (Man-C4-Chol) into small unilamellar long circulating liposomes consisting of cholesterol (Chol) and distearoyl phosphatidylcholine (DSPC). In the in vitro cellular uptake study with cultured mouse peritoneal macrophages, [(3)H]Man-liposomes were taken up to a great extent, whereas no significant uptake was observed for [(3)H]cholesterol and DSPC liposomes without Man-C4-Chol (Bare-liposomes). The uptake of [(3)H]Man-liposomes was dose- and temperature-dependent and inhibited by an excess of mannosylated bovine serum albumin, suggesting their specific uptake via membrane mannose receptor-mediated endocytosis. Furthermore, it was demonstrated that (111)In-MBP binds strongly to Man-liposomes based on the recognition of Man-C4-Chol and markedly enhanced their uptake by macrophages. These results are supported by confocal laser microscopic images. In addition, in vivo hepatic uptake of (111)In-MBP was enhanced by Man-liposomes. On the other hand, the uptake of Man-liposomes was significantly reduced by preincubation with serum and further with MBP-depleted serum suggesting inhibitory effects of serum proteins such as albumin on mannose receptor-mediated endocytosis. The involvement of serum-type MBP and membrane mannose receptors in the uptake of Man-liposomes is thus suggested.

p53 expression in the gastric mucosa before and after eradication of Helicobacter pylori

BACKGROUND

Accumulation of p53 has been recognized in the gastric mucosa infected with Helicobacter pylori. We investigated the prevalence of p53-positive cells in the gastric mucosa before and one month after eradication of H. pylori and the relationship between p53 positivity and inflammation and cell proliferation.

METHODS

The subjects included 24 H. pylori-positive patients. They achieved eradication one month after anti-H. pylori therapy. Biopsies were taken from the greater curvatures of the antrum and middle body. H. pylori status was assessed using culture and tissue section (Giemsa stain). Serial sections were used for examination of gastritis (hematoxylin and eosin stain) and for immunostaining of p53, Ki-67 and myeloperoxidase (MPO). p53 index and Ki-67 labeling index (LI) were calculated by counting p53-positive and Ki-67-positive cells in the entire gastric pits longitudinally sectioned and expressing them as a percentage of the total cells in a gastric pit. In the neck regions with and without p53-positive cells, polymorphonuclear leukocytes (PMNs) were counted in the corresponding area (/50 x 50 microm2) of the sections stained both with p53 and MPO.

RESULTS

p53-positive cells decreased significantly after eradication of H. pylori. Before eradication, the number of PMNs was significantly higher in the neck regions with p53-positive cells than in those without.

CONCLUSIONS

In the gastric mucosa infected with H. pylori, p53-positive cells were found in the neck region infiltrated with PMNs. p53 expression decreased significantly one month after eradication of H. pylori.

Follistatin production by skin fibroblasts and its regulation by dexamethasone

Activin and follistatin (FS) appear to play a role in the development of the skin and its appendages, in the inflammatory process, angiogenesis, and in wound healing. Although there is information on the expression of activin subunits and receptors in fibroblasts and keratinocytes, there are no reports on the regulation of FS expression in these cells. In the present study we analyzed the splicing variants of FS mRNAs in fibroblasts from genital and nongenital skin by RT-PCR and northern analysis, and examined the induction of FS mRNA and protein by hormones and growth factors in skin fibroblasts from human and nonhuman primates. FS mRNA was highly expressed in all fibroblast strains with similar expression regardless of donor species (human or monkey), donor age (neonate or adult), or the organ from which the fibroblast strains were established (skin or pituitary, genital or non-genital skin). Moreover, the band density corresponding to FS-288 was <5-10% of the value for FS-315 in skin fibroblasts as in all other tissues examined. Fibroblast FS mRNA and protein production were biphasically regulated by dexamethasone: low concentrations (0.01 and 0.1 nM) increased whereas higher concentrations (>1 nM) suppressed FS expression. On the other hand, androgens, activin and PACAP38 were without effect. These data establish cultured skin fibroblasts as a model to study FS gene expression in humans, and support a role for follistatin in the normal immune response and in the anti-inflammatory actions of glucocorticoids.

PTEN/MMAC1/TEP1 mutations in human primary renal-cell carcinomas and renal carcinoma cell lines

Extensive allelotyping studies have implicated several tumor-suppressor loci on chromosomes 3p, 5q, 6q, 8p, 9pq, 10q, 11q, 14q, 17p, 18q and 19p in human kidney tumorigenesis. The PTEN (also called MMAC1 and TEP1) gene, a candidate tumor suppressor located at chromosome 10q23.3, is mutated in a variety of sporadic malignancies as well as in patients with Cowden disease. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma-derived cell lines, using DNA-SSCP, sequencing and microsatellite analysis. Five of 68 (7.5%) primary RCCs exhibited intragenic mutations (3 missense, 1 deletion and 1 splice-site), and 1 of 17 (5.9%) cell lines had an insertion mutation. Loss of heterozygosity of the PTEN gene occurred in 25% of primary RCCs, including the 3 cases with intragenic mutation and the 1 PTEN-mutated cell line. Clinical and histopathological examinations revealed that 4 of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. The other was a low-stage papillary/chromophilic RCC. Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype.

Novel galactosylated liposomes for hepatocyte-selective targeting of lipophilic drugs

Novel galactosylated neutral liposomes containing cholesten-5-yloxy-N-(4-((1-imino-2-beta-D-thiogalactosylethyl)amino)butyl)formamide (Gal-C4-Chol) as a "homing" device were developed for hepatocyte-selective drug targeting. Distearoylphosphatidylcholine (DSPC)/cholesterol (Chol) (60:40) and DSPC/Chol/Gal-C4-Chol (60:35:5) liposomes were prepared and labeled with [3H]cholesteryl hexadecyl ether (CHE). [3H]Prostaglandin E1 (PGE1) and [14C]probucol were incorporated in liposomes as model lipophilic drugs. After intravenous injection of the liposomes, mice were sacrificed at suitable time periods, and the lung, liver, kidney, spleen, and heart were excised. DSPC/Chol/Gal-C4-Chol liposomes rapidly disappeared from the blood, and 85% of the dose had accumulated in the liver within 10 min compared with hepatic accumulation of DSPC/Chol liposomes of 12%. The liver was perfused with collagenase, and liver parenchymal cells (PC) and liver nonparenchymal cells (NPC) were separated by centrifugal differentiation to determine the cellular distribution. The PC/NPC ratios for DSPC/Chol/Gal-C4-Chol and DSPC/Chol liposomes were 15.1 and 1.1, respectively. The hepatic uptake of DSPC/Chol/Gal-C4-Chol liposomes, but not that of DSPC/Chol liposomes, was significantly inhibited by the predosing of galactosylated bovine serum albumin. [14C]Probucol and [3H]PGE1 incorporated in DSPC/Chol/Gal-C4-Chol liposomes was also efficiently delivered to the liver. In conclusion, newly developed galactosylated liposomes have been proven to be a useful carrier for hepatocyte-selective targeting that will have many practical applications.

[Gynecologic and obstetric disorders presenting with abdominal pain]

This article briefly reviews the clinical settings and imaging findings of gynecologic/obstetric disorders presenting with abdominal pain. MR imaging is considered to be an excellent modality for the diagnosis of these disorders because of its high sensitivity to blood. Although CT allows images to be obtained within a shorter time than does MR imaging, the possibility of pregnancy should be excluded prior to the examination. Hemorrhagic ovarian cyst exhibits hyperintensity on T1-weighted images or hematocrit effect on CT or MR images. Hemoperitoneum associated with hemorrhagic cyst strongly indicates rupture of the cyst. Rupture of endometrial cysts and dermoid cysts can cause acute chemical peritonitis. In ectopic pregnancy, findings of hematosalpinx associated with strong enhancement of the tubal wall frequently contribute to the diagnosis. Torsion of the adnexa can be diagnosed by the pedicle between the ovary and uterus, and the lack of contrast enhancement. Tuboovarian abscess is recognized as a cystic mass having a thick wall that is strongly enhanced. Among complications of uterine leiomyoma, red degeneration shows characteristic MR findings, hyperintense rim on T1-WI, hypointense rim on T2-WI, and lack of contrast enhancement. Because of the high incidence of OHSS associated with normal pregnancy, CT is contraindicated.

PTEN/MMAC1/TEP1 mutations in human primary renal-cell carcinomas and renal carcinoma cell lines

Extensive allelotyping studies have implicated several tumor-suppressor loci on chromosomes 3p, 5q, 6q, 8p, 9pq, 10q, 11q, 14q, 17p, 18q and 19p in human kidney tumorigenesis. The PTEN (also called MMAC1 and TEP1) gene, a candidate tumor suppressor located at chromosome 10q23.3, is mutated in a variety of sporadic malignancies as well as in patients with Cowden disease. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma-derived cell lines, using DNA-SSCP, sequencing and microsatellite analysis. Five of 68 (7.5%) primary RCCs exhibited intragenic mutations (3 missense, 1 deletion and 1 splice-site), and 1 of 17 (5.9%) cell lines had an insertion mutation. Loss of heterozygosity of the PTEN gene occurred in 25% of primary RCCs, including the 3 cases with intragenic mutation and the 1 PTEN-mutated cell line. Clinical and histopathological examinations revealed that 4 of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. The other was a low-stage papillary/chromophilic RCC. Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype.

Inhibitory effect of N-acetylcysteine on invasion and MMP-9 production of T24 human bladder cancer cells

BACKGROUND

MMPs play a crucial role in the process of cancer invasion and metastasis.

METHODS

The influence of NAC on invasion and MMP-9 production of human bladder cancer cell line T24 was investigated using an in vitro invasion assay, gelatin zymography, Western and Northern blot analyses and RT-PCR assays.

RESULTS

TPA increased the number of invading T24 cells through reconstituted basement membrane more than 10-fold compared to basal condition. NAC inhibited TPA-enhanced invasion dose-dependently. TPA increased the MMP-9 production by T24 cells without altering expression of TIMP-1 gene, while NAC suppressed TPA-enhanced production of MMP-9. Neither TPA nor NAC altered TIMP-1 mRNA level in T24 cells. In vitro experiments demonstrated that MMP-9 was directly inhibited by NAC but was not influenced by TPA.

CONCLUSION

NAC limits invasion of T24 human bladder cancer cells by inhibiting the MMP-9 production in addition to a direct inhibition of MMP-9 activity.

Results of three-year mass screening programme for lung cancer using mobile low-dose spiral computed tomography scanner

The aim of this study was to evaluate the usefulness of annual screening for lung cancer by low-dose computed tomography (CT) and the characteristics of identified lung cancers. Subjects consisted of 5483 general population aged 40-74 years, who received initial CT scans in 1996, followed by repeat annual scans for most subjects in 1997 and 1998, with a total of 13 786 scans taken during 1996-1998. Work-up examinations for patients with suspicious lesions were conducted using diagnostic CTs. The initial screening in 1996 detected suspicious nodules in 279 (5.1%) of 5483 subjects, and 22 (8%) were confirmed surgically to have lung cancer. Corresponding figures in 1997 and 1998 screening studies were 173 (3.9%) of 4425 and 25 (14%) of 173, and 136 (3.5%) of 3878 and 9 (7%) of 136, respectively. The sensitivity and specificity of detecting surgically confirmed lung cancer were 55% (22/40) and 95% (4960/5199) in 1996 and 83% (25/30) and 97% (4113/4252) in 1997 screening, respectively. 88% (55/60) of lung cancers identified on screening and surgically confirmed were AJCC stage IA. Our trial allowed detection of nearly 11 times the expected annual number of early lung cancers. Repeat CT allowed the detection of more aggressive, rapidly growing lung cancers, compared to those in the initial screening.

Double-labeled donor probe can enhance the signal of fluorescence resonance energy transfer (FRET) in detection of nucleic acid hybridization

A set of fluorescently-labeled DNA probes that hybridize with the target RNA and produce fluorescence resonance energy transfer (FRET) signals can be utilized for the detection of specific RNA. We have developed probe sets to detect and discriminate single-strand RNA molecules of plant viral genome, and sought a method to improve the FRET signals to handle in vivo applications. Consequently, we found that a double-labeled donor probe labeled with Bodipy dye yielded a remarkable increase in fluorescence intensity compared to a single-labeled donor probe used in an ordinary FRET. This double-labeled donor system can be easily applied to improve various FRET probes since the dependence upon sequence and label position in enhancement is not as strict. Furthermore this method could be applied to other nucleic acid substances, such as oligo RNA and phosphorothioate oligonucleotides (S-oligos) to enhance FRET signal. Although the double-labeled donor probes labeled with a variety of fluorophores had unexpected properties (strange UV-visible absorption spectra, decrease of intensity and decay of donor fluorescence) compared with single-labeled ones, they had no relation to FRET enhancement. This signal amplification mechanism cannot be explained simply based on our current results and knowledge of FRET. Yet it is possible to utilize this double-labeled donor system in various applications of FRET as a simple signal-enhancement method.