Detection of epstein-barr virus in nasal T-cell lymphoma

The close relationship between Epstein-Barr virus (EBV) and nasal T-cell lymphoma (NTL) has frequently been reported. However, the status of the infection, either lytic or latent, is obscure. This study involved 16 patients with NTL. Phenotypes of lymphoma cells were examined by immunohistochemical staining using CD3, CD4, CD8, CD20 and CD45RO monoclonal antibodies. EBV-encoded small nuclear RNA (EBER)-1 and EBV NotI tandem repeat region were detected by reverse transcription, using a rapid (< or = 60 min) in situ hybridization technique. Tumor cells expressed at least one T-cell marker, such as CD3, CD4, CD8 and CD45RO. CD20 was not detected in any of the cases. EBER-1 was identified in all cases; no Notl tandem DNA repeat was demonstrated. All cases demonstrated a T-cell phenotype. These data suggest that NTL is associated with EBV infection in the latent phase.

Cdk4/cyclin D1 kinase, a universal and critical regulator of apoptosis

BACKGROUND

We have previously described that overexpression of cdk4/cyclin D1 is the primary and critical mediator of apoptosis in PC12 cells even under otherwise physiological conditions. However, it is unclear whether this phenomenon is specific to neuronal cells or is more universally true.

MATERIALS AND METHODS

Cyclins and cdks were transiently overexpressed in a variety of cultured cells, and examined for apoptosis.

RESULTS

By flow cytometry, apoptosis was observed in all cell lines overexpressing cdk4 or cyclin D1. Immunofluorescence revealed that cells overexpressing cdk4 or cyclin D1 exhibited nuclear features characteristic of apoptosis. Furthermore, in cells defective for retinoblastoma protein (Rb), apoptosis could be induced by overexpression of any cdks or cyclins.

CONCLUSION

Up-regulation of cdk4 kinase activity is the primary and critical mediator of apoptosis regardless of the cell types. In addition, inactivation of Rb renders cells further susceptible to apoptosis by abnormal expression of any of the cell cycle regulators.

Rapid induction of peroxisome proliferator-activated receptor gamma expression in human monocytes by monosodium urate monohydrate crystals

OBJECTIVE

Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a member of the nuclear hormone receptor superfamily and functions as a key regulator of lipid and glucose metabolism, atherosclerosis, and inflammatory responses. This study was undertaken to evaluate the biologic role of PPAR gamma in self-limiting episodes of acute gouty arthritis. To do this, we investigated PPAR gamma expression by monosodium urate monohydrate (MSU) crystal-stimulated monocytes, and we studied the effects of PPAR gamma ligands on crystal-induced acute inflammation.

METHODS

PPAR gamma expression by MSU crystal-stimulated human peripheral blood mononuclear cells was determined by reverse transcription-polymerase chain reaction and immunostaining. Expression of CD36 on monocytes was detected by flow cytometric analysis. The effects of PPAR gamma ligands on in vitro crystal-induced cytokine production and on in vivo cellular infiltration during crystal-induced acute inflammation were also investigated.

RESULTS

MSU crystals rapidly and selectively induced PPAR gamma expression by monocytes. Gene expression was detected as early as 2 hours, and maximum expression was observed at 4 hours after stimulation. The induced PPAR gamma was functional, since a PPAR gamma ligand was able to up-regulate CD36 expression on monocytes. A natural ligand of PPAR gamma, 15-deoxy-Delta(12,14)-prostaglandin J(2) (15deoxy-PGJ(2)), significantly reduced the crystal-induced production of cytokines by monocytes. Indomethacin inhibited cytokine production only at high concentrations, and an antidiabetic thiazolidinedione (troglitazone) failed to exert significant effects. Administration of troglitazone and 15deoxy-PGJ(2) significantly prevented cellular accumulation in a mouse air-pouch model of MSU crystal-induced acute inflammation.

CONCLUSION

Rapid induction of PPAR gamma expression on monocytes by MSU crystals may contribute, at least in part, to the spontaneous resolution of acute attacks of gout.

Paradoxical expression of cell cycle inhibitor p27 in endometrioid adenocarcinoma of the uterine corpus - correlation with proliferation and clinicopathological parameters

p27 is regarded as a cyclin-dependent kinase inhibitor of the G1-to-S cell cycle progression by suppressing the kinase activity of cyclin/cyclin-dependent kinase complex. This study aimed to investigate p27 expression in the normal endometrium and endometrioid adenocarcinoma of the uterine corpus and the correlation of its expression with cell proliferation and clinicopathological parameters. Tissue samples of 127 endometrioid adenocarcinomas and 15 normal endometria were used in the study. Immunohistochemical staining for detecting p27 and Ki-67 was performed by the labelled streptavidin-biotin method on formalin-fixed and paraffin-embedded tissue samples. The expression was given as the labelling index, which indicates the percentage of positive nuclei. p27 staining was observed in the nuclei of the glandular cells in the functional layer of the secretory phase endometrium, whereas it was negative in those of the proliferative phase. In endometrioid adenocarcinomas, the labelling index of p27 expression paradoxically increased more significantly in the higher histological grades and was correlated with that of Ki-67. The high level of p27 expression was associated with clinicopathological parameters such as FIGO stage, lymph node metastasis, lymphovascular space involvement and myometrial invasion. High p27 expression was linked to higher grades of endometrioid adenocarcinoma, cell proliferation and some clinical prognostic factors. These results indicate that p27 might be an indicator of poor prognosis.

Expression of cyclin A in endometrial adenocarcinoma and its correlation with proliferative activity and clinicopathological variables

PURPOSE

Cyclin A is known as an S- and G2-M phase regulatory protein and its abnormal expression has been reportedly implicated in cellular proliferation. This study was designed to investigate the correlation of cyclin A expression with tumorigenesis of the endometrium and clinicopathological variables.

METHODS

Immunohistochemical staining using labeled streptavidin-biotin complex was performed on formalin-fixed, paraffin-embedded tissue of normal endometrium (15 cases), endometrial hyperplasia (23 cases), and endometrial adenocarcinoma (endometrioid type) (112 cases).

RESULTS

Immunohistochemistry showed that the nuclei of the cells were positive for cyclin A. In normal endometrium, only proliferative phase was focally positive for cyclin A. Cyclin A was also positive for endometrial hyperplasia. Its expression in hyperplasia was significantly more frequent than that of proliferative phase and less than that of endometrioid adenocarcinoma. The labeling index (LI) of cyclin A in endometrioid adenocarcinoma was 16.3+/-6.9 in well-differentiated, 18.3+/-8.8 in moderately differentiated, and 30.2+/-11.8 in poorly differentiated adenocarcinoma, respectively. Cyclin A expression increased significantly more in high histological grades. The area of squamous metaplasia in endometrioid adenocarcinoma was negative for cyclin A. The LI of cyclin A was positively correlated with that of Ki-67 and cyclin-dependent kinase 2. Cyclin A expression was significantly associated with carcinoma without coexisting endometrial hyperplasia and lymphovascular space involvement (LVSI), but not with FIGO stage, myometrial invasion, lymph node metastasis, estrogen receptor, progesterone receptor, and menopause as well as recurrence.

CONCLUSIONS

Cyclin A expression was involved in the progression to malignancy of the endometrium and was correlated with proliferative activity and prognostic features including histological grade, without coexisting endometrial hyperplasia and LVSI.

Clinical significance of p53, mdm2, and bcl-2 proteins in renal cell carcinoma

OBJECTIVES

To improve our understanding of the clinical relevance of p53, mdm2, and bcl-2 protein overexpression in renal cell carcinoma, we retrospectively investigated the immunohistochemical expression of p53, murine double minute 2 (mdm2), and bcl-2 and the relationship of this expression to clinicopathologic characteristics. p53 regulates the transcription of downstream effectors such as the oncoprotein mdm2, and bcl-2 has been shown to inhibit apoptosis triggered by wild-type p53.

METHODS

The expression of p53, mdm2, and bcl-2 protein was studied by immunohistochemical methods in paraffin-embedded nephrectomy specimens from 112 patients whose clinicopathologic data confirmed renal cell carcinoma.

RESULTS

The expression of the p53 and bcl-2 protein was recognized in 15 (13.4%) and 52 (42.0%) cases, respectively; the expression of the mdm2 protein, however, was seen in only 2 cases (1.8%). No correlation was noted between these three proteins and any clinicopathologic parameters, except p53 expression and Stage T1-2/T3-4 (P = 0.0208). However, in multivariate analysis, stage (hazard ratio 3.586; P = 0.0002), expression of p53 (hazard ratio 6.090; P = 0.0126) and of mdm2 (hazard ratio 22.016; P = 0.0156), and coexpression of p53/mdm2 (hazard ratio 6.146; P = 0.0005) demonstrated a statistically significant effect on prognosis by proportional hazards regression tests.

CONCLUSIONS

Our results indicate that stage, p53 expression, mdm2 expression, and coexpression of p53/mdm2 are useful to predict the clinical outcome in patients with renal cell carcinoma.

Hyalinizing spindle cell tumor with giant rosettes: report of a case showing remarkable myofibroblastic differentiation

We examined the proliferative activity and the differentiation line of tumor cells in a case of "hyalinizing spindle cell tumor with giant rosettes" (HSCGR). A 6 cm tumor within the right deltoid muscle of a 58-year-old female was found by physical and radiographical examinations. A biopsy revealed the histological features of a spindle cell tumor with rosette-like structures. Wide excision was done under the diagnosis of HSCGR. The tumor presented as a gray-whitish, solid mass with focal pseudocystic degeneration. Immunohistochemically, the tumor cells were diffusely positive for vimentin and were also focally positive for S-100, but negative for desmin and alpha-smooth muscle actin. The cells stained positively for Ki-67 with even distribution, there being a correlation with the cellularity of the areas, with a labeling index ranging from 0.3 to 0.5%. In addition, flow cytometry revealed an almost normal diploid DNA pattern and 5.8% S-phase fraction, indicating low proliferative activity. Ultrastructurally, many tumor cells displayed discontinuous basal lamina, pinocytotic vesicles, dilated rough endoplasmic reticulum, and microfilaments with focal dense bodies. The main component of the rosette was collagenous fibrils with normal diameter and normal periodic banding. We interpreted this case of HSCGR as a low grade fibrosarcoma with remarkable differentiation of myofibroblastic lineage, and with focally accumulated, morphologically normal collagenous fibrils.

Antitumor effect of bcl-2 antisense phosphorothioate oligodeoxynucleotides on human renal-cell carcinoma cells in vitro and in mice

BACKGROUND AND PURPOSE

Programmed cell death is a genetically regulated pathway that is altered in many cancers. This process is, in part, regulated by the bcl-2 oncogene. Antisense oligodeoxynucleotides (ODNs) targeted to specific oncogenes have been used with some therapeutic success in animal models of leukemia and melanoma cells and human Hodgkin's lymphoma. We evaluated the effects of antisense ODNs targeted to the bcl-2 oncogene on the proliferation of human renal-cell carcinoma (RCC) cells in vitro and on the growth of human RCC xenografts in BALBc nude (nu/nu) mice.

MATERIALS AND METHODS

Expression bcl-2 mRNA in five RCC cell lines (ACHN, Caki-1, RCZ, RCW, and OS-RC-2) was analyzed by reverse transcriptase-polymerase chain reaction. The effects of phosphorothioated ODNs containing human bcl-2 sense and bcl-2 antisense sequences that were transfected with Lipofectin on the proliferation and viability of cultures of established human RCC cell lines were determined by MTS assay. The expression of Bcl-2 protein in ACHN tumor cells following antisense bcl-2 (AS2) ODN treatment was evaluated by Western blot analysis, and the extent of apoptosis in these cells was determined by fluorescence-activated cell sorter (FACS) analysis. The antitumor activity in ACHN xenografts in nu/nu mice was monitored by measuring differences in tumor weight in treated and control mice.

RESULTS

Expression of bcl-2 mRNA was detected in all five RCC lines. Treatment with antisense bcl-2 ODNs inhibited the growth of all tested RCC cells and decreased Bcl-2 protein expression in ACHN cells. The AS2 antisense ODN complementary to the coding region of bcl-2 mRNA showed a superior antiproliferative effect compared with AS1 ODN complementary to the translation initiation region. Inhibition by antisense bcl-2 ODNs of ACHN cells was dose dependent. The FACS analysis revealed that growth inhibition was associated with the induction of programmed cell death. In vivo, AS2 ODN antitumor activity was noted in locally injected groups.

CONCLUSIONS

Treatment of human RCC with antisense ODNs targeted to bcl-2 inhibits growth and is associated with the induction of programmed cell death. These results suggest therapeutic use of antisense bcl2 in the treatment of RCC.

Expression of Pit-1 and growth hormone-releasing hormone receptor mRNA in human pituitary adenomas: difference among functioning, silent, and other nonfunctioning adenomas

We analyzed the expression of Pit-1 and growth hormone-releasing hormone receptor (GHRH-R) mRNA in various types of functioning and nonfunctioning adenomas using a quantitative reverse transcriptase polymerase chain reaction (RT-PCR) method. Among clinically nonfunctioning adenomas, tumors considered as silent adenomas were reclassified on a pathologic basis. Competitive RT-PCR showed that the levels of Pit-1 and GHRH-R mRNA expression in silent somatotroph adenomas and silent prolactinomas were similar to those in the corresponding functioning adenomas. In silent thyrotroph adenomas, both mRNAs showed high levels of expression that were similar to those in functioning and silent somatotroph adenomas. The results suggest that the cause of the silence in these tumors seems to be in the downstream to transcription of Pit-1 gene in the signaling pathway leading to hormone secretion. Competitive RT-PCR assay could distinguish silent adenomas of the Pit-1 group from the other nonfunctioning adenomas in the expression levels of Pit-1 and GHRH-R mRNAs. In the future, precise diagnosis of various adenomas may become possible by assaying transcription factors such as steroidogenic factor-1 and thyrotroph embryonic factor, which are thought to be related to adenohypophyseal cytodifferentiation.

Overexpression of cdk4/cyclin D1 induces apoptosis in PC12 cells in the presence of trophic support

The induction of apoptosis by cell cycle regulator molecules under conditions optimal for exponential growth was examined in rat pheochromocytoma PC12 cells by overexpression of cyclins and cyclin-dependent kinases (cdks). By flow cytometry and by immunofluorescence, only cells overexpressing cdk4 or cyclin D1 underwent apoptosis, which was not associated with G1-arrest. Cdk4 kinase activity was significantly higher in cdk4-, or cyclin D1-expressing cells. Furthermore, induction of apoptosis by cdk4 was abrogated by co-transfection of p16(INK4), or dominant negative cdk4. These results suggest that upregulation of cdk4 kinase activity is a primary and critical mediator of apoptosis in PC12 cells under physiological conditions.

Comparison of the DNA extraction methods for polymerase chain reaction amplification from formalin-fixed and paraffin-embedded tissues

To obtain an adequate quality and quantity of DNA from formalin-fixed and paraffin-embedded tissue, six different DNA extraction methods were compared. Four methods used deparaffinization by xylene followed by proteinase K digestion and phenol-chloroform extraction. The temperature of the different steps was changed to obtain higher yields and improved quality of extracted DNA. The remaining two methods used microwave heating for deparaffinization. The best DNA extraction method consisted of deparaffinization by microwave irradiation, protein digestion with proteinase K at 48 degrees C overnight, and no further purification steps. By this method, the highest DNA yield was obtained and the amplification of a 989-base pair beta-globin gene fragment was achieved. Furthermore, DNA extracted by means of this procedure from five gastric carcinomas was successfully used for single strand conformation polymorphism and direct sequencing assays of the beta-catenin gene. Because the microwave-based DNA extraction method presented here is simple, has a lower contamination risk, and results in a higher yield of DNA compared with the ordinary organic chemical reagent-based extraction method, it is considered applicable to various clinical and basic fields.

Clinicopathologic significance of telomerase activity and hTERT mRNA expression in non-small cell lung cancer

Telomerase has been reported to be a novel diagnostic marker for malignant diseases and has been recently proven to be composed of three main components, hTR (human telomerase RNA component), TP1 (telomerase-associated protein 1) and hTERT (human telomerase reverse transcriptase), the last of which plays a key role in telomerase activation. In the present study, quantitative levels of telomerase activity and hTERT gene mRNA (hTERT) expression were analyzed in cancerous and non-cancerous lung tissues of 62 lung cancer patients by telomeric repeat amplification protocol and reverse transcription-PCR, respectively. The telomerase expression levels of each group of tissue samples were compared with clinicopathologic variables. Telomerase activity and hTERT were detected in cancerous tissues (75.8 and 75.8%, respectively), while these parameters were not observed in any non-cancerous tissues. In quantitative assessment of telomerase expression, both telomerase activity and hTERT were significantly correlated with lymph node metastasis (N0 vs. N1+2, P<0.05). Telomerase activity also correlated with tumor cell differentiation and stage classification (P<0.05), but did not correlate with other clinicopathologic variables. The disease-free survival in patients with lung cancer demonstrated that patients with hTERT-positive tumor survived for a significantly shorter period than those with hTERT-negative tumor (P=0.0334). Since hTERT levels are correlated with N factor which represents the true aggressiveness of patients' disease concerning the evaluation of clinical outcome, hTERT was found to be one of the important markers revealing biological malignant potentials for lung cancer.

CDK-inhibitors-associated kinase activity: a possible determinant of malignant potential in smooth muscle tumors of the external soft tissue

There has been accumulating histological observation of leiomyoma and leiomyosarcoma of the external soft tissue regarding their differential diagnosis. The definitive diagnostic tools have not been established, however, nor have the pathological mechanisms of cell proliferation in these tumors been clarified. Herein, expression of the cyclin-dependent kinase inhibitors (CKIs), p21, p27 and p57 and their associated kinase activities were examined in 61 cases of soft tissue smooth muscle tumors. Immunohistochemical staining showed that all 3 inhibitor proteins were expressed in all cases of leiomyoma and leiomyosarcoma, but that the mean values of their labeling indices (LIs) were higher in the cases of leiomyosarcoma. In addition, the LIs of p21 and p27 were inversely correlated in total cases. Immunoblotting revealed that these proteins are expressed at higher levels in tumors, in particular, in leiomyosarcoma. When CKIs were immunoprecipitated from tissue extracts, cyclin/cdk protein complexes associated with, at least, 1 CKI were detectable only in tumor tissues. Furthermore, cdk2 or cdk4 kinase activity manifested by these cyclin/cdk/CKI complexes (CKI-associated kinase activity) was detectable exclusively from leiomyosarcoma, but not from leiomyoma. Among the cases of leiomyosarcoma, cdk2 activity was generally found associated either with p21 or p27, but not both. Statistical analysis indicated that p21- and p27 LIs are predictive of positive or negative clinical outcome, respectively. In conclusion, the participation of CKIs in active cyclin/cdk complexes in a reciprocal and redundant manner and subsequent CKI- associated kinase activity are the characteristic profiles of malignant phenotype in these tumors. Moreover, immunohistochemical detection of CKIs may provide a useful tool for evaluating patients' prognosis.

Co-expression of N-cadherin and alpha-fetoprotein in stomach cancer

Although N-cadherin is necessary for organ formation originating in the endoderm, the expression of N-cadherin in gastric carcinoma and its role has not yet been reported. The present study was conducted to determine the pattern of immunohistochemical expression of E-cadherin and N-cadherin, using formalin-fixed, paraffin-embedded tissues from 97 primary gastric carcinomas, including 17 which were producing alpha-fetoprotein (AFP). Samples were subdivided into 50 tubular adenocarcinomas and 47 poorly differentiated adenocarcinomas. Results showed that E-cadherin was expressed in varying degrees in areas of cell adhesion between tumor cells, in 94 out of 97 cases studied. Three cases which showed no expression of E-cadherin were diagnosed as AFP-producing tumors by immunohistochemistry. Expression of N-cadherin was observed in varying degrees in the intercellular spaces between tumor cells in 11 tubular adenocarcinomas and in six poorly differentiated adenocarcinomas, including E-cadherin-negative cases, all of which were AFP positive. The present findings suggest a possible role for N-cadherin in gastric carcinoma.

A pharmacological study of the weekday-on/weekend-off oral UFT schedule in colorectal cancer patients

PURPOSE

The new weekday-on/weekend-off schedule for oral UFT administration consists of its administration for 5 consecutive days followed by 2 days off the drug. The intratumor 5-FU (5-fluorouracil) concentration has been reported to be correlated to the tumor response in patients treated with intravenous 5-FU. The aim of this study was to investigate the pharmacokinetics during the 2 days off the drug in cancer patients treated with the weekday-on/weekend-off schedule for oral UFT.

METHODS

The subjects were 24 colorectal cancer patients. They were divided into three groups, and were all given UFT, 600 mg/day, for 5 days before surgery. Surgery was performed 2, 24, or 48 h after the final dose of UFT. The 5-FU concentrations in the serum, tumor, and in the normal mucosa were measured.

RESULTS

The serum 5-FU concentrations after the final dose of UFT were: 23 +/- 12 ng/ml (mean +/- SD) at 2 h, 7 +/- 3 ng/ml at 24 h, and 6 +/- 3 ng/ml at 48 h. The intratumor 5-FU concentrations were: 113 +/- 45 ng/g at 2 h, 54 +/- 20 ng/ml at 24 h, and 54 +/- 35 ng/ml at 48 h, and the concentrations in the normal mucosa were: 36 +/- 15 ng/g (mean +/- SD) at 2 h, 17 +/- 6 ng/ml at 24 h, and 18 +/- 6 ng/ml at 48 h after the final dose. While the serum 5-FU concentration decreased to very low levels by 24 h after the final dose of UFT, the intratumor 5-FU concentrations were maintained at more than 50 ng/g at least until 48 h after the final dose. The 5-FU concentrations in the normal mucosa were maintained at about one third of the intratumor concentrations at all time points.

CONCLUSION

Although the weekday-on/weekend-off schedule for UFT administration included intermittent 2-day drug-off periods, this pharmacokinetic study revealed that the 5-FU concentrations in the tumor were maintained at much higher levels than in the serum throughout these periods.

The MEN1 gene and associated diseases: an update

Heterozygous germline mutations of the tumor suppressor gene MEN1 are responsible for multiple endocrine neoplasia type 1 (MEN1), a dominantly inherited familial cancer syndrome characterized by the combined occurrence of pituitary, parathyroid, and enteropancreatic tumors. Various types of mutations likely causing loss of the gene function have been identified throughout the entire gene region in patients with MEN1 and related disorders including a small fraction of familial isolated hyperparathyroidism (FIHP). Neither mutation hot spot nor phenotype-genotype correlation has been established in classical MEN1, although some missense mutations may be specifically associated with a phenotype of FIHP. Familial isolated pituitary tumor and atypical familial MEN1 consisting of only pituitary tumor and hyperparathyroidism usually lack germline MEN1 mutations, suggesting that these familial endocrine tumor syndromes are genetic entities distinct from MEN1. DNA test for MEN1 germline mutations is a robust tool for diagnosis of predisposition to MEN1, and will be useful for the counseling and management of patients and their families. In this review, we will summarize the most recent findings on the MEN1 gene, focusing primarily on germline mutations and associated diseases.

APC protein is required for initiation of neuronal differentiation in rat pheochromocytoma PC12 cells

The adenomatous polyposis (APC) gene product is highly expressed in the central nervous system. To elucidate the contribution of the APC protein to neuronal differentiation, we used an inducible antisense mRNA vector to suppress APC protein expression and examined neuronal differentiation of PC12 cells induced by nerve growth factor (NGF). When antisense mRNA was induced, APC protein expression was suppressed to 20% of the noninduced level. In those cells, neurite extension induced by NGF and expression of microtubule-associated protein 2 (MAP2) was completely inhibited. However, once cells had differentiated, antisense APC mRNA expression and subsequent suppression of APC protein expression had no effect on either cell morphology or MAP2 protein expression. These results suggest that the wild type APC is critically involved only in the initiation of neuronal differentiation, but not in the maintenance of the differentiated phenotype, or that the neuronal phenotype could be maintained at lower level of APC protein.

Adsorption equilibriums of principal herbicides on paddy soils in Japan

Herbicides used in paddy fields during the flooding season can easily cause pollution by run-off into rivers or by other routes. It is very important to know the adsorption characteristics that influence their fate in the soil. The adsorption equilibriums have often been expressed by Henry equations, and the values of equilibrium constant, Kd, are estimated from the adsorption constants, K(OC), based on organic carbon contents of soils. There is little information concerning the equilibrium values expressed by the Freundlich equations, and insufficient information on the actual concentration levels in the paddy field. Therefore, adsorption equilibriums of the five principal herbicides: esprocarb, mefenacet, pretilachlor, simetryn and thiobencarb, on five kinds of paddy soil in Japan were investigated. It was found that their equilibrium values were better expressed by the Freundlich equation for concentration levels for the paddy fields, and that the values for the adsorption coefficient, n, varied from 1.0 to 1.6. Values for the coefficient, k, were in the range of 29-420 mg(1 - 1/n) l(1/n)/kg-dry, and the values were poorly related to solubilities in water or to the octanol-water partition coefficients of the herbicides. For each herbicide, except for simetryn, the values of k among the soils differed by 2-3 times, and no correlation could be found with the organic carbon contents, specific surface areas, pH, cation exchange capacity or major minerals of the soils. The adsorption equilibriums calculated from the values of adsorption constant Kd by the values of K(OC) in the literature were found to be very different from the experimental equilibriums. From the experimental values of coefficient k and n of the Freundlich equation, the maximum runoff concentrations of the herbicides were preliminarily estimated by a simple equilibrium model.

Pulmonary adenocarcinoma with heterotopic bone formation

Adenocarcinoma of the lung is a common malignancy. Frequently, this tumor can cause calcification within a primary tumor. However, an extremely rare occurrence in lung carcinomas is ossification within a primary tumor, and to our knowledge only three cases have been reported. We report a case of pulmonary adenocarcinoma with ossification, and discuss the pathogenesis of intratumoral ossification with a review of the literature.

Long-term survival after immunochemotherapy for juvenile colon cancer with peritoneal dissemination: a case report

A 20 year-old man was hospitalized with an abdominal mass and abdominal distension. Investigations resulted in a diagnosis of ileus caused by advanced colon cancer with peritoneal dissemination to the pouch of Douglas. Palliative surgery was performed to relieve bowel obstruction and debulk the tumor. Histopathological examination showed that the tumor was a mucinous adenocarcinoma invading the serosa without lymph node metastasis. Ascites collected during the operation was diagnosed as class V. Administration of PSK (3.0 g/day) and UFT (600 mg/day) as adjuvant immunochemotherapy was started postoperatively to achieve tumor dormancy. He has been followed as an outpatient for 2.5 years with no ascites or abdominal symptoms.

[A survey of current nutrition therapy for the ALS patients in Japanese national sanatoriums]

To evaluate the current nutrition therapy for the patients of amyotrophic lateral sclerosis (ALS) in Japan, we sent questionnaires to 53 Japanese national sanatoriums (hospitals) and were able to collect replies from 42 institutes. In these replies, information on 466 patients (262 inpatients and 204 outpatients) was reported, accounting for about 10% of all Japanese ALS patients. Patients who ate orally were more frequent (p < 0.001, chi 2 test) in the outpatients (76.0%) than in the inpatients (39.7%). When the subjects were limited to non-orally nourished cases, gastrostomy was more frequently performed (p < 0.05, chi 2 test) in the outpatients (49%) than in the inpatients (29.1%), but no significant differences were observed between the above two groups as to the quantity of daily caloric intake; the mode was 1000-1200 Cal. About a quarter of non-orally nourished patients received supplemental sodium chloride, and fewer were supplemented copper and/or zinc. The consent of the patients as well as the clinical findings weighed heavily in the determination of the feeding route. Most physicians were disinclined to encourage tube feeding in the early stage of dysphagia, but were supportive of the operation of percutaneous endoscopic gastrostomy when non-oral nutrition therapy became necessary. Although the efficacy of vitamins for ALS has not been proved, 45 of 58 physicians agreed to subscribe vitamins to their patients, especially vitamin B12, E and C.

High prevalence of spinocerebellar ataxia type 1 (SCA1) in an isolated region of Japan

Autosomal dominant cerebeller ataxias (ADCAs) are a heterogeneous group of neurodegenerative disorders that differ in both the clinical manifestations and modes of inheritance. At present, eight different genes causing ADCAs have been found: spinocerebeller ataxia type 1 (SCA1), SCA2, SCA3/Machado-Joseph disease (MJD), SCA6, SCA7, SCA8, SCA12 and dentatorubropallidoluysian atrophy (DRPLA). The relative prevalence of each mutation varies according to race and native place. We studied 117 unrelated ADCA families that originated from the Tohoku District in the northernmost part of Honshu Island in Japan (mainly Miyagi Prefecture in the central part of Tohoku District). The SCA1 mutation was the most frequent among the known disorders (24.8% of all such families). The relative prevalence of SCA1 in the Tohoku District is very high compared with the values already reported from other regions in the world. Because the population of this area had seldom moved, the alleles with SCA1 mutations (including alleles with an intermediate CAG repeat number) are assumed to have been present in this area for a long time.

Thymic hyperplasia as a source of ectopic ACTH production

A 26 year-old man with suspected Cushing's disease underwent transsphenoidal exploration of the pituitary without any evidence of microadenoma or hyperplasia. Progressive hypercortisolism necessitated bilateral adrenalectomy. Postoperatively, skin pigmentation gradually developed with a marked elevation of plasma ACTH levels, and CT scanning uncovered a thymic mass. Following removal of the thymic mass, skin pigmentation disappeared and plasma ACTH levels fell to normal. The excised mass was found to be a benign thymic hyperplasia without epithelial or carcinoid tumor cells. However, gel chromatography showed that the thymic tissue extract contained high ACTH content comparable to that of ectopic ACTH-producing tumors with a major component corresponding to ACTH(1-39). Northern blot analysis and in situ hybridization revealed the expression of proopiomelanocortin transcripts in lymphocytes of thymic hyperplasia. This report suggests that lymphocytes in thymic hyperplasia are the most likely site of deregulated ACTH expression causing ectopic ACTH syndrome.

Induction of neutrophil death resembling neither apoptosis nor necrosis by ONO-AE-248, a selective agonist for PGE2 receptor subtype 3

An increase of intracellular cAMP mediated by prostaglandin E2 (PGE2) has been shown to delay spontaneous apoptosis of neutrophils. It has been demonstrated that a selective agonist for PGE2 receptor subtype 3 (the EP3 receptor) is capable of decreasing cAMP and stimulating phosphoinositide turnover in various types of cells. We investigated the effect of a selective EP3 receptor agonist, ONO-AE-248, on neutrophil viability. ONO-AE-248 rapidly caused a unique form of neutrophil death. The agonist primarily induced morphological changes of the nucleus, including fusion of the lobules, decreased compactness of the chromatin, and blebbing and rupture of the nuclear membrane. This was followed by an increase of plasma membrane permeability and cell lysis. During these processes, neither apoptotic changes such as nuclear condensation, DNA fragmentation, and expression of phospholipid phosphatidylserine on the plasma membrane nor necrotic changes such as chromatin clumping and organelle destruction were apparent in the treated neutrophils. The fatal effect of the agonist night be specific for neutrophils because it failed to promote the rapid death of other types of cells. Although activation of neutrophils by ONO-AE-248 was not evident, experiments using metabolic inhibitors demonstrated that the agonist caused neutrophil death via the activation of protein kinase C in the presence of intracellular ATP. These findings indicated that EP3 receptor-mediated signals might promote a novel form of neutrophil death, which differs from typical apoptosis or necrosis.

Involvement of cyclins in cell proliferation and their clinical implications in soft tissue smooth muscle tumors

Expression of cyclins A and E and cyclin-dependent kinase 2 (cdk2) was examined immunohistochemically in 55 cases of soft tissue smooth muscle tumors, including vascular leiomyoma, and compared to expression of Ki-67 and proliferating cell nuclear antigen. Cyclin A was expressed in 70% of the leiomyoma cases, but with much lower labeling indexes than in leiomyosarcoma. Cyclin E was expressed exclusively in leiomyosarcoma. Although the differences of cyclin A- and cyclin E-labeling indexes between leiomyoma and leiomyosarcoma were statistically significant, no significant differences were found in the other markers. Furthermore, cyclin A- and/or E-positivity predicted a poor prognosis in recurrence- or metastasis-free survivals and overall survival. Immunoblotting revealed that cyclins A and E were expressed, in complex with cdk2, exclusively in tumors. In addition, not only leiomyosarcoma, but also leiomyoma specimens that exhibited negligible levels of complex expression, manifested detectable cdk2 activity. These results suggest 1) up-regulation of active cyclin A/cdk2 expression and associated kinase activity is critical for unrestrained cell proliferation; 2) cyclin E/cdk2 complexes may play a crucial role in leiomyosarcoma; 3) immunohistochemical detection of cyclins can be a more reliable tool for differential diagnosis between leiomyoma versus leiomyosarcoma than that of Ki-67 or proliferating cell nuclear antigen, and be a possible prognostic indicator.

Simultaneous suppression of cdc2 and cdk2 activities induces neuronal differentiation of PC12 cells

The involvement of cdc2 and cdk2 during neuronal differentiation in rat pheochromocytoma PC12 cells was examined. When PC12 cells were cultured with nerve growth factor (NGF), expression of cdc2 decreased significantly after day 5, while expression of cdk2 decreased gradually after day 7. Cells overexpressing cdc2 or cdk2 were resistant to NGF-induced differentiation and growth suppression, and maintained high cdc2 or cdk2 kinase activity, respectively, during NGF treatment. In contrast, the NGF-treated parental cells showed a marked decline in these kinase activities after day 3. When PC12 cells were treated with specific inhibitors of cdc2/cdk2 (butyrolactone-I, olomoucin), they showed marked neurite extension and up-regulation of microtubule-associated protein 2 expression. In addition, treatment with mixtures of antisense oligonucleotides for cdc2 and cdk2 resulted in down-regulation of both cdc2 and cdk2 kinase activities as well as significant neurite outgrowth and up-regulation of microtubule-associated protein 2 expression. However, neurite outgrowth was not observed in cells treated with either single antisense oligonucleotide, or antisense cdc2 + cdk4 or cdk2 + cdk4 oligonucleotide mixtures. These results suggest that simultaneous down-regulation of cdc2 and cdk2 activity is sufficient and necessary for neuronal differentiation in PC12 cells.

Semiquantitative immunoblot analysis of nm23-H1 and -H2 isoforms in adenocarcinomas of the lung: prognostic significance

Total amounts of nm23 protein and relative levels of H1 and H2 isoforms were studied in 27 fresh-frozen samples of pulmonary adenocarcinoma and adjacent non-neoplastic tissues that were obtained at surgery. Semiquantitative immunoblotting with a monoclonal antibody (Pan-242) against nm23 protein demonstrated both isoforms, recognized as 20.5 kDa for H1 and 18.5 kDa for H2, to be present in all cases. Both H1 and H2 levels in neoplastic tissues were higher than in the corresponding non-neoplastic samples. Expression of H2 was usually greater than of H1. The H2/H1 ratio varied from 1.9 to 14.1 (mean value 5.2) in non-neoplastic tissues and 1.0-5.9 (mean value 2.5) in neoplastic tissues, although this ratio did not correlate with any prognostic factor like tumor size, nodal status or distant metastasis (TNM tumor stage). H1 and H2 levels were significantly lower (mean values 4.3 and 2.4) in well-differentiated than in moderately and poorly differentiated adenocarcinomas (8.3 and 3.0) (P < 0.03 and P < 0.05, respectively). These data indicate that H1 and H2 isoform levels correlate with histological differentiation, but not the metastatic potential or stage of pulmonary adenocarcinoma.

Relationship between p53 gene mutation and protein expression: clinical significance in transitional cell carcinoma of the bladder

Although the mutated p53 gene has been postulated to induce immunohistochemically-detectable p53 protein, reports regarding the relationship between p53 mutation and p53 protein expression have been contradictory. This study investigated the relationship between p53 mutations and p53 expression and their clinical significance for patients with transitional cell carcinoma of the bladder. Eighty-seven transitional cell carcinoma of the bladder were analyzed by immunohistochemistry (IHC) for p53 nuclear accumulation, and the results compared to mutations detected in the p53 gene evaluated by polymerase chain reaction single-strand conformation polymorphism (SSCP) and DNA sequence analysis. By p53 IHC analysis, positive p53 staining was observed in 50 (57.5%) of the 87 tumors. The specificity of IHC, defined as a percentage of IHC negative (<20%) tumors among tumors without mutation, was 94.6%. Despite the good concordance between p53 mutation and p53 protein expression (p<0.0001), 48.0% (24/50) of the tumors showed p53 overexpression without mutation, and 2 (5.4%) tumors with mutation showed no p53 immunoreactivity. Patients with higher grade (grade 3), stage (stages pT2-4), and p53 mutations had a poorer prognosis by Kaplan-Meier survival analysis. A Cox univariate analysis found that grading (hazard ratio 3.139; p=0.002), staging (hazard ratio 3.832; p=0.0005) and p53 mutation (hazard ratio 2.498; p=0.013) were significant variables in these patients, but no variable was independently associated with an increased survival of bladder carcinoma by multivariate analysis. We found that a 20% cut-off level of p53 overexpression showed the highest correlation with prognosis and p53 mutation, however, p53 overexpression and mutation were not superior to staging as prognostic markers. These data suggest that careful assessment of the TNM staging system remains the most reliable predictive indicator of survival for patients with transitional cell carcinoma of the bladder.

Proprotein-Processing Endoprotease Furin and its Substrate Parathyroid Hormone-Related Protein Are Coexpressed in Insulinoma Cells

Parathyroid hormone-related protein (PTHrP) is frequently produced in pancreatic endocrine tumors. PTHrP is synthesized as the precursor pro-PTHrP and undergoes a series of posttranslational processing reactions, among which cleavage of a 12 amino acid sequence from its precursor is crucial for the biological activation of PTHrP. This cleavage is catalyzed by furin, a proprotein-processing endoprotease that cleaves the consensus sequence -Arg-X-(Lys/Arg)-Arg-X-. We previously reported that furin is highly expressed in rat pancreatic islets during the perinatal stage and that the expression of furin in pancreatic-cells induces faster cell growth. From this, we postulated that furin may be co-expressed with PTHrP in insulinomas. We immunostained insulin, PTHrP, and furin in 21 human pancreatic endocrine tumors: 10 insulinomas, 5 VIPomas, 4 gastrinomas, and 2 somatostatinomas. Of these 21 endocrine tumors, furin was positively stained in all 10 insulinomas. Likewise, PTHrP was detected in the same insulinomas. We found one VIPoma and one gastrinoma contained a few insulin-positive cells scatteringly, which were also positive for furin and PTHrP. But other non-insulinoma endocrine tumors did not display furin and PTHrP positivity. We conclude that furin and its substrate pro-PTHrP are co-expressed specifically in insulinomas.

Cardiac dendritic cells and acute myocarditis in the human heart

Cardiac dendritic cells are considered to play an important role in the immunoresponse of the heart. However, it is unclear whether these cells occur in human myocarditis and whether they function in similar ways to those in rats. Cardiac samples were obtained from 22 autopsied patients with myocarditis, and compared with 20 age-and sex-matched controls. Formalin-fixed hearts were immunostained by the LSAB method. Cardiac dendritic cells were detectable even in the control hearts (1.5 cells/high power field (HPF)). In the acute phase of myocarditis, the number of cardiac dendritic cells increased up to 12.6 cells/HPF (p<0.001). In the subacute phase of myocarditis, T cells (36.6 cells/HPF) and HLA-DR+ cells (10.2 cells/HPF) continued to infiltrate the periphery of the inflammatory lesions, but they had no expression without inflammation. In this study, cardiac dendritic cells were reactive for HLA-DR, but negative for CD68, and were characteristically large monocytes with long, slender, dendritic processes. Accordingly, they were clearly distinguishable from macrophages. In the human heart, cardiac dendritic cells may be recruited in the acute phase of myocarditis, and seem to play an important role in the succeeding immunoresponse.

The expression of MMP-2 and TIMP-2 in patients with primary colorectal adenocarcinoma: correlation with liver metastasis

The expression of MMP-2 and TIMP-2 was examined immunohistochemically in a total of 36 colorectal cancer patients with synchronous liver metastasis at the time of surgery, and the serum MMP-2 and TIMP-2 levels were also measured in a total of 58 colorectal cancer patients with/without liver metastasis following primary colorectal surgical resection for serological comparison. Although MMP-2 exhibited a significant expression immunohistochemically in the primary colorectal cancer (p<0.05) and TIMP-2 in the synchronous liver metastasis (p<0.01), there was no relationship between the absence/presence of liver metastasis and serum MMP-2 and TIMP-2 levels, respectively. These results suggest that it can be considered difficult to use serum MMP-2 and TIMP-2 levels to predict the status of liver metastasis following primary resection in patients with colorectal adenocarcinoma.

Which technique, circular stapled anastomosis or double stapling anastomosis, provides the optimal size and shape of rectal anastomotic opening?

BACKGROUND

Two types of end-to-end colorectal anastomosis using a circular stapler, circular stapled anastomosis(CSA) and double stapling anastomosis(DSA), have become the standard technique. The possibility of anastomotic openings of the DSA being smaller and somewhat distorted, because of some portion of the stapled rectal stump not being included in the anastomotic opening, was examined.

METHODS

Anastomotic openings created by CSA and DSA were photographed through a sigmoidoscope, and the maximal and minimal diameters and the areas of the anastomotic openings were measured and calculated with an image analyzer. They were examined in the swine rectum immediately after surgery and were also examined in the randomized clinical cases 3 or more months after surgery.

RESULTS

It was found that larger anastomotic openings could be created as the diameter of the anastomosed intestine and the cartridge size became wider in both methods immediately after surgery. The shape of anastomotic opening created by DSA was observed to be more oval than round immediately after surgery. The anastomotic stenosis occurred in a small number of patients in both methods within 3 months after surgery. The area of the anastomotic opening created by CSA was about 25% larger than that by DSA immediately after surgery and about 30% larger 3 or more months after surgery.

CONCLUSION

CSA provides a larger anastomotic opening than DSA. Anastomotic stenosis occurred in a small number of patients in both methods.

Leptomeningeal melanomatosis with multiple cutaneous pigmented nevi: tumor cell proliferation and malignant transformation in an autopsy case

We experienced a rare case of leptomeningeal melanomatosis. The proliferative activity and nuclear accumulation of p53 in this tumor were examined, since the relationship between this tumor type and growth has not yet been elucidated. A 33-year-old Japanese man was shown to have leptomeningeal melanomatosis with multiple cutaneous pigmented nevi. The autopsy findings showed the presence not only of benign diffuse melanosis of the leptomeninges but also of leptomeningeal melanomatosis in the subarachnoid space and brain parenchyma. In the brain parenchyma, the direct invasion of tumor cells from the subarachnoid space and Virchow-Robin spaces filled with melanoma cells were observed. Multiple hemorrhagic areas invaded by melanoma cells were also present. Immunohistochemical staining with a monoclonal antibody to melanoma cells showed positivity in the tumor cells. Proliferation analysis using the MIB-1 antibody demonstrated that the labeling index of tumor cells invading brain parenchyma (2.54%) was higher than that in other lesions of the inner (0.89%) and outer layer (0.76%) of the subarachnoid space. Nuclear accumulation of p53 protein was rarely seen in the tumor cells. We reported a case of leptomeningeal melanomatosis. Higher proliferative activity was found in invading cells of the brain parenchyma. Malignant transformation of the tumor did not appear to be associated with p53 gene mutation.

Cystic lesion at the foramen magnum disseminated from a pituitary adenoma--case report

A 38-year-old male presented with a cystic lesion at the foramen magnum due to intracranial dissemination from a pituitary adenoma. The primary tumor had required reoperation for regrowth twice. The tumor at the foramen magnum was removed surgically. Two smaller solid tumors were located in the left parietal convexity and the right temporal lobe. The former tumor was also removed surgically and the latter was observed. Histological examination showed the typical characteristics of pituitary adenoma in both surgical specimens. Immunohistochemical staining with MIB-1 and p53 antibodies showed low (< 1%) and negative reaction. Patients with pituitary adenoma, even benign tumors, must be carefully followed up for signs of metastasis.

A novel apoptotic cascade mediated by CDK4 in rat pheochromocytoma PC12 cells

Apoptosis induced by serum withdrawal in pheochromocytoma PC12 cells is promoted by overexpression of cyclin-dependent kinase 4 (CDK4). We compared CDK4-promoted apoptosis with that induced by serum withdrawal alone in PC12 cells. Protein synthesis inhibitors did not prevent apoptosis in parental cells, but prevented the promotion of apoptosis by CDK4 overexpression. Nerve growth factor, basic-fibroblast growth factor, and Bcl-2 proteins protected both parental and CDK4-overexpressing cells from apoptosis. However, insulin-like growth factor-I and Bcl-X(L) protein only partially inhibited apoptosis in the CDK4-overexpressing cells. Bcl-2 or Bcl-X(L) had no significant effect on CDK4 kinase activity in both cell lines. These results suggest a novel CDK4-mediated apoptotic cascade which is normally restrained, but which is activated by CDK4 overexpression. This apoptotic cascade should eventually converge with the cascade induced by serum withdrawal in normal PC12 cells. We discuss the interactions among these apoptotic cascades and the points where anti-apoptotic agents act.

Combined clear and granular cell leiomyoma of soft tissue: evidence of transformation to a histiocytic phenotype

AIMS

We present an unusual case of leiomyoma with a clear and granular cell pattern in which there was immunohistochemical evidence of transformation to a histiocytic phenotype.

METHODS AND RESULTS

A 64-year-old man presented with mild scrotal swelling and pain. A local excision was performed after the clinical diagnosis of epidermal inclusion cyst. In the pathological specimen, another tumour nodule was identified which was composed predominantly of clear cells, with an occasional mixture of granular cells. Immunohistochemical analysis demonstrated positive staining for vimentin, lysozyme, CD68 and HAM56, but complete negativity for desmin, alpha-smooth muscle actin, HHF35, S100 protein, neurone-specific enolase and CD34. Ultrastructural study revealed dilated rough endoplasmic reticulum, glycogen granules, abundant vacuolar structures and also thin microfilaments with subplasmalemmal dense bodies.

CONCLUSIONS

Based on these findings, we have interpreted it to be a rare case of leiomyoma with extensive clear cell and granular cell degeneration (combined clear and granular cell leiomyoma). This complete transformation of the immunohistochemical profile into the histiocytic phenotype has not been previously described in the literature.

Morphological characterization and subtyping of silent somatotroph adenomas

GH-producing adenomas clinically are endocrine-active tumors accompanied with acromegaly in most instances. However, GH-producing adenomas apparently unassociated with acromegaly, or so-called silent somatotroph adenomas (SSA), have recently been reported but rarely. The reported cases are characterized by normal or slightly elevated serum levels of GH but without acromegaly. Tumor cells contain moderate, trace or no GH immunoreactivity. We experienced 7 cases of SSA which were not always similar in morphology and pathogenetic mechanism. They could be further divided into the following 3 subtypes. Subtype 1 (N = 2): a moderate number of cells were immunopositive for GH, and GH mRNA was also expressed in moderate or numerous cells. Densely granulated cells were noted. It is assumed that inhibition of hormone release into circulation. Subtype 2 (N = 3): a small number of cells were immunopositive for GH, while GH mRNA was expressed in numerous tumor cells. They were sparsely granulated cells containing fibrous bodies. These findings suggest that posttranslational processing of the gene product may be defective. Subtype 3 (N = 2): Only a scattered number of cells were immunopositive for GH and GH mRNA was co-localized in immunopositive cells. They were sparsely granulated cells containing poorly developed organelles that did not resemble those of typical sparsely granulated GH cells. The findings indicate that adenoma cells are largely immature with minimal GH lineage differentiation.

The significance of frequent and independent p53 and bcl-2 expression in large-cell neuroendocrine carcinomas of the lung

Both p53 and bcl-2 genes are involved in regulating cell death. Reports, however, concerning the relationship between p53 and bcl-2 expression are contradictory. Large-cell neuroendocrine carcinoma (LCNEC) of the lung is a newly recognized clinicopathologic entity. p53 mutation and bcl-2 overexpression are frequent in small-cell lung carcinoma (SCLC), and we observed a close correlation between bcl-2 expression and cellular neuroendocrine (NE) differentiation in non-SCLC, so we speculated that LCNEC, an NE tumor closely related to SCLC, would exhibit high incidence of both p53 alteration and bcl-2 expression. Immunohistochemical expression of p53 and bcl-2 was evaluated on consecutive sections of 26 LCNECs, including 4 combined LCNECs. p53 accumulation and diffuse bcl-2 staining were observed in 18 (69.2%) of 26 and 24 (92.3%) of 26 LCNECs, respectively, but their immunoreactivities showed no fixed distribution relevance on consecutive sections in individual tumors. Statistical analyses yielded no relationship between p53 and bcl-2 expression (P = .47). In all of the four combined LCNECs, p53 was identically either positive or negative in both tumor cell populations with and without NE differentiation. bcl-2 immunoreactivity was observed only for the tumor cells with NE phenotype in three of the four combined LCNECs and was diffuse among the NE tumor cells but geographic in distribution among the non-NE tumor cells of the remaining one combined LCNEC. Thus, our present findings suggest that p53 and bcl-2 are expressed independently and might have distinct expression significance in LCNECs. A high incidence of p53 expression in LCNECs and equal p53 expression profiles in NE and non-NE tumor cell populations of combined LCNECs suggest that p53 alteration is primarily involved in the tumorigenesis of LCNEC. On the other hand, frequent bcl-2 expression in pure LCNECs and selective bcl-2 expression in tumor cells with NE phenotype in combined LCNECs are suggestive of a role for bcl-2 in regulating cellular NE differentiation.

Tumor extension and cell proliferation in adenocarcinomas of the lung

To elucidate the mechanism of tumor extension in human pulmonary adenocarcinoma, we immunohistochemically investigated the expression of cell cycle regulator proteins in 54 small adenocarcinomas less than 3 cm in diameter. The Ki-67-labeling index was significantly higher in the periphery of the tumor nodule than in the center. This proliferative potential correlated well with coexpression of cdk2 and cyclin A. p27, one of the cdk inhibitors, was highly expressed in normal bronchial epithelial cells. Peripherally located tumor cells expressed p27 at an intermediate level, but at a higher frequency and level than those in the center. Expression of p21 was also predominant in the periphery. Furthermore, the expression patterns of p21 and p27 were reciprocal. In vitro kinase assays further demonstrated higher cdk2 kinase activity in the periphery. These results suggest that: (i) within an emerging extension made up of peripherally located tumor cells, their high proliferative potential gradually wanes as their relative topographical position becomes more central in the expanding tumor; (ii) peripherally located tumor cells maintain their proliferative potential by higher cyclin A-cdk2 complex activity; and (iii) intermediate expression of p21/p27 in the peripherally located cells promotes higher cyclin A-cdk2 kinase activity, whereas high p21/p27 expression in nonneoplastic cells inhibits kinase activity.

Human cytomegalovirus infection in foci of Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus (HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection and expression of TNFalpha. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated with HCMV infection.

Significance of growth hormone-releasing hormone receptor mRNA in non-neoplastic pituitary and pituitary adenomas: a study by RT-PCR and in situ hybridization

This study examined the expression of human growth hormone-releasing hormone receptor (GHRH-R) mRNA in both non-neoplastic pituitary tissues and pituitary adenomas by reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization (ISH). RT-PCR analysis showed that all of the non-neoplastic pituitaries and all GH-producing adenomas, one prolactinoma and one third of the non-functioning adenomas expressed GHRH-R mRNA. ISH demonstrated that all of GH-producing adenomas and two prolactinomas expressed GHRH-R mRNA. The expression of GHRH-R mRNA in GH-producing adenomas was greater than that in the other adenomas by RT-PCR and ISH. GHRH-R mRNA detected by ISH was observed only in GH cells from the pituitary gland of a young girl. In pituitary adenomas, a diffuse signal was observed in the cytoplasm of all of the GH-producing adenomas and in two prolactinomas. Expression of GHRH-R mRNA was not seen in normal prolactin cells, or in any adenomas other than GH-producing adenomas and a few prolactinomas. These results suggest that GHRH-R mRNA plays a role mainly in the function of GH-producing adenomas but may also play a role in function of some prolactinomas.

GH and PRL-Producing Pituitary Adenoma with Neuron-Like Differentiation

A pituitary adenoma with neuron-like differentiation in the sella turcica is reported. Sections of the tumor showed a mixture of adenoma cells, ganglionic cells, and neuropil-like structures by light microscopy. Both pituitary adenoma cells and large cells recognized as ganglionic cells by H&E were strongly immunoreactive for both growth hormone (GH) and prolactin (PRL), which indicated that these large cells had properties similar to those of pituitary adenoma cells. Furthermore, electron microscopy (EM) revealed characteristic low electron-dense secretory granules as well as GH-type large electron-dense secretory granules in adenoma cells, neuropils, and swollen bulbs of neuronal endings, which indicated that these three populations may be of the same origin. Furthermore, we could not find typical cell bodies of ganglionic cells by EM. These results are consistent with a hypothesis that attempts to explain the origin of the neuronal components by the neuronal differentiation of adenoma cells. Thus, the best designation of our tumor may be "pituitary adenoma with neuron-like differentiation."

CDK4, a possible critical regulator of apoptosis in rat pheochromocytoma PC12 cells

The function of cell cycle regulator molecules during apoptosis induced by serum withdrawal was examined in rat pheochromocytoma PC12 cells. When human cDNAs encoding cyclins, cyclin-dependent kinase 2 (CDK2), CDK4, and cell-division cycle 2 (CDC2), were introduced, only CDK4-overexpressing cells were more prone to apoptosis compared with parental cells. In the parental cells, serum withdrawal resulted in the upregulation of CDK4 protein expression 6.6-fold for the first 12 h after serum withdrawal. In contrast, CDK4 protein levels in CDK4-overexpressing cells remained constant for the first 12 h followed by a gradual decline. Expression of cyclin D1 was upregulated in both cell lines. The change in CDK4 kinase activity almost paralleled that of CDK4 protein expression. These results suggest that CDK4 kinase activity is one of the critical regulators in the apoptotic cascade in PC12 cells.

Neuron-specific enolase-producing epithelioid leiomyosarcoma with gross vascular invasion and intracardiac involvement

We present an unusual case of epithelioid leiomyosarcoma in the right shoulder. A 10-cm tumor eroding the right scapula occurred in a 59-year-old man and grew into the subclavian vein with extension to the right atrium. An elevated serum level of neuron-specific enolase was also detected. Clinical presentation suggested small cell carcinoma of the lung (Pancoast tumor) with intravenous extension. Eventually, the patient died of respiratory insufficiency. Autopsy revealed a primary tumor in the right shoulder, numerous tumor emboli in the pulmonary arteries, and associated hemorrhagic infarction. Histopathologic features revealed an epithelioid leiomyosarcoma. Furthermore, immunohistochemical and immunoblotting analyses of the tumor demonstrated positive reactions for neuron-specific enolase. We interpreted this peculiar case to be a neuron-specific enolase-producing epithelioid leiomyosarcoma of the soft tissue associated with gross vascular invasion.