Genomic profiling of multiple tissues in two patients with multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant tumor syndrome. This hereditary cancer is caused by germline variants in MEN1. Two patients with MEN1 were identified via whole exome sequencing and gene expression profile analysis, conducted for 5,063 patients with various types of cancers. We obtained multiple tumors from each patient; tumors derived from these two MEN1 patients had a loss of the normal MEN1 allele and frequently chromosomal copy number changes. Thus, we investigated whether structural variants were present in the MEN1 patient genomes. Whole-genome sequencing revealed no catastrophic rearrangements, and the tumor samples had very low somatic variants. The two patients had germline variants in MEN1 and some chromosomal copy number changes including on chromosome 11. The only pathogenic variant detected was the MEN1 germline variant, and chromosomal rearrangements led to tumorigenesis in somatic cells. Furthermore, the MEN1 tumor samples displayed a specific signature characterized by T:A>C:G transition. Studies of multiple tumors obtained from single patients are rare in hereditary cancer syndromes, and our results provide insights that the second hit of the tumor suppressor gene MEN1 may be caused by a gross genome rearrangement, not a small insertion and deletion, nor a change in epigenetic regulation.

Classification and Prognostic Stratification of Bronchopulmonary Neuroendocrine Neoplasms

The accuracy and reproducibility of the World Health Organization (WHO) 2015 classification of bronchopulmonary neuroendocrine neoplasms (BP-NENs) is disputed. The aim of this study is to classify and grade BP-NENs using the WHO 2019 classification of digestive system NENs (DiS-NEN-WHO 2019), and to analyze its accuracy and prognostic impact. Two BP-NEN cohorts from Japan and Germany, 393 tumors (88% surgically resected), were reviewed and the clinicopathological data of the resected tumors (n = 301) correlated to patients' disease-free survival (DFS). The DiS-NEN-WHO 2019 stratified the 350 tumors into 91 (26%) neuroendocrine tumors (NET) G1, 52 (15%) NET G2, 15 (4%) NET G3, and 192 (55%) neuroendocrine carcinomas (NEC). NECs, but not NETs, were immunohistochemically characterized by abnormal p53 (100%) and retinoblastoma 1 (83%) expression. The Ki67 index, which was on average 4 times higher than mitotic count (p < 0.0001), was prognostically more accurate than the mitotic count. NET G3 patients had a worse outcome than NET G1 (p < 0.01) and NET G2 patients (p = 0.02), respectively. No prognostic difference was detected between NET G3 and NEC patients after 5 year DFS. It is concluded that stratifying BP-NEN patients according to the DiS-NEN-WHO 2019 classification results in 3 prognostically well-defined NET groups, if grading is solely based on Ki67 index. Mitotic count alone may underestimate malignant potential of NETs.

Clinicopathological Profiling of Lung Carcinoids with a Ki67 Index > 20

The clinicopathological features of lung neuroendocrine neoplasms (NEN) with a high proliferative index at the border area between atypical carcinoid and neuroendocrine carcinoma have not been investigated so far. The aim of this study was, therefore, to search for lung NENs which are well differentiated but show Ki67 values that overlap with those of poorly differentiated (PD)-NENs. Resected lung NENs from 244 Japanese patients were reviewed, and Ki67 indices were assessed in all tumors. The data were then correlated to clinicopathological parameters and patient outcome. Among 59 (24%) well-differentiated (WD)-NENs and 185 (76%) lung PD-NENs, 7 were defined as WD-NENs with Ki67 indices > 20%. The Ki67 indices of these tumors (mean 29%, range 24-36) were significantly lower than those of PD-NENs (mean 74%, range 34-99). All WD-NENs with Ki67 > 20% lacked abnormal p53 and loss of retinoblastoma 1 (Rb1) expression. In contrast, many PD-NENs expressed p53 (48%) and showed loss of Rb1 (86%). The 2- and 5-year disease-free survival rates in WD-NEN patients with Ki67 > 20% were lower than those of WD-NEN patients with Ki67 ≤20% (p < 0.01 for disease-free and overall survival). No statistical differences were detected between outcome of WD-NEN patients with Ki67 > 20% and those of PD-NEN. It is concluded that WD-NEN patients with Ki67 > 20% share the morphological and immunohistochemical features of WD-NEN patients with Ki67 ≤20%, but they have a worse prognosis, suggesting that this tumor group requires particular attention in future classifications and probably new therapeutic regimes.

Inflammation and PD-L1 expression in pulmonary neuroendocrine tumors

In the light of novel cancer immune therapies, the status of antitumor inflammatory response and its regulation has gained much attention in patients with lung cancer. Ample datasets exist for non-small-cell lung cancer, but those for pulmonary neuroendocrine tumors are scarce and controversial. Here, tumor-associated inflammation, CD8+ cell infiltration and PD-L1 status were evaluated in a cohort of 57 resected carcinoids and 185 resected neuroendocrine carcinomas of the lung (58 large cell carcinomas and 127 small cell carcinomas). Data were correlated with clinicopathological factors and survival. Moderate or high tumor-associated inflammation was detected in 4 carcinoids (7%) and in 37 neuroendocrine carcinomas (20%). PD-L1 immunoreactivity was seen in immune cells of 73 (39%) neuroendocrine carcinomas, while tumor cells were labeled in 21 (11%) cases. Inflammatory cells and tumor cells in carcinoids lacked any PD-L1 expression. In neuroendocrine carcinomas, PD-L1 positivity in immune cells, but not in tumor cells, was associated with intratumoral CD8+ cell infiltration (P < 0.001), as well as with the severity of tumor-associated inflammation (P < 0.001). In neuroendocrine carcinomas, tumor-associated inflammation and PD-L1 positivity in immune cells correlated with prolonged survival and the latter factor was also an independent prognosticator (P < 0.01, hazard ratio 0.4 for overall survival, P < 0.001 hazard ratio 0.4 for disease-free survival). Taken together, in neuroendocrine tumors, antitumor inflammatory response and PD-L1 expression are largely restricted to neuroendocrine carcinomas, and in this tumor entity, PD-L1 expression in inflammatory cells is positively correlated to patient survival.

A New Possible Lung Cancer Marker: VGF Detection from the Conditioned Medium of Pulmonary Large Cell Neuroendocrine Carcinoma–Derived Cells using Secretome Analysis

The prognosis of malignant neuroendocrine tumors of the lung is known to be very poor. Aiming to identify new markers of pulmonary neuroendocrine tumors in early stages and also differential diagnostic markers between large cell neuroendocrine carcinoma and small cell lung cancer, we comprehensively analyzed peptides which were secreted into conditioned medium by LCN1, a large cell neuroendocrine carcinoma cell line. Specific peaks in conditioned medium but not in used medium alone were detected using matrix-associated laser desorption/ionization time of flight mass spectrometry. Two peptide fragments of 40 and 19 amino acid residues were identified by matrix-associated laser desorption/ionization time of flight mass spectrometry. These two fragments were demonstrated to be parts of VGF nerve growth factor inducible (VGF), which is usually expressed in nerve cells or neuroendocrine cells. RT-PCR analysis of lung cancer cell lines showed that VGF mRNA was expressed only in neuroendocrine carcinoma–derived cells. Our data suggest that VGF can be used as a novel serological diagnostic marker of pulmonary neuroendocrine tumors.

ProGRP is a possible tumor marker for patients with Ewing sarcoma

We analyzed serum ProGRP levels in patients with Ewing sarcoma, and found that 5 out of 9 patients had elevated levels; the values range equally with those of patients with limited disease of small-cell lung carcinoma. Serum ProGRP levels in patients with bone and soft tissue malignancies other than Ewing sarcoma are not elevated. Immunohistochemical studies demonstrated that ProGRP-like immunoreactivities were detected in Ewing sarcoma tissues obtained from 2 patients with elevated serum ProGRP levels, suggesting that ProGRP is a product of tumor cells of Ewing sarcoma. These results indicate that serum ProGRP could serve as a specific tumor marker for Ewing sarcoma. Since ProGRP is a major hormonal product of tumor cells of small-cell lung carcinoma, a typical neuroendocrine carcinoma, it is reasonable to postulate that the present study provides an evidence for Ewing sarcoma to possess neuroendocrine differentiation.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia with a central and peripheral carcinoid and multiple tumorlets: a case report emphasizing the role of neuropeptide hormones and human gonadotropin-alpha

We report a case of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH). We performed immunohistochemical analysis of 17 neuropeptides and human gonadotropin-alpha (hCGα), a trophoblastic peptide that promotes the proliferation of neuroendocrine cells. A 51-year-old woman with no history of smoking was found to have a nodule in the right middle lobe. Upon examination, the nodule was found to comprise diffuse linear and nodular neuroendocrine cell hyperplasia (NECH), numerous pulmonary tumorlets merging with one peripheral carcinoid, and an additional central carcinoid. Immunohistochemical analysis revealed diffuse but intense expression of the general neuroendocrine markers CD56, synaptophysin, and chromogranin A, together with gastrin-releasing peptide (GRP), calcitonin, and hCGα throughout the carcinoids, tumorlets, and NECH. Positive staining was also noted for adrenocorticotropic hormone, corticotropin-releasing hormone, met-enkephalin, vasoactive intestinal polypeptide, neurotensin, and growth hormone-releasing hormone in a few isolated cells of the carcinoids and the tumorlets, but staining for these proteins was entirely negative in the NECH lesions. The presence of these neuropeptides in neuroendocrine tumors might explain the presence of neuropeptide-producing tumors of the lungs, cases of which have been reported over the last 30 years. The preoperative serum proGRP level was high but returned to normal after surgical intervention, indicating that GRP was produced and secreted by carcinoids, tumorlets, and/or NECH lesions. It is also probable that neuroendocrine cells secreted GRP into the interstitium in a paracrine manner, leading to the development of dense fibrosis around the tumorlets. During the preoperative and postoperative periods, no evidence of bronchiolitis obliterans was noted, in contrast to some previously reported cases of DIPNECH.

Large cell neuroendocrine carcinoma of the lung: is it possible to diagnose from biopsy specimens?

OBJECTIVE

We have recently proposed new diagnostic criteria for high-grade non-small cell neuroendocrine carcinoma, i.e. possible large cell neuroendocrine carcinoma, in biopsy specimens and have started a clinicopathological comparative study of high-grade neuroendocrine carcinomas in an advanced stage. This study aimed to elucidate the usefulness of our diagnostic criteria for inoperable advanced large cell neuroendocrine carcinoma and to know the true incidence of large cell neuroendocrine carcinoma among lung cancers.

METHODS

We reviewed all cancer lesions (1040 specimens) obtained by transbronchial lung biopsies in our hospital from 2002 to 2009 and selected 38 biopsy specimens that satisfied our diagnostic criteria for high-grade non-small cell neuroendocrine carcinoma. All 38 cases were clinicopathologically investigated and all biopsy specimens were precisely studied for their morphological characteristics.

RESULTS

Clinicopathological information about the selected 38 cases was very similar to the clinicopathological characteristics of large cell neuroendocrine carcinoma reported. Of 38 cases, six were at Stage I, II or IIIA, underwent surgery, and the diagnosis was confirmed to be large cell neuroendocrine carcinoma using surgical tumor specimens. In the 38 biopsy specimens, features of neuroendocrine morphology such as organoid nesting, peripheral palisading and rosette formation were not frequent histological features and the majority of tumor cells contained nuclei with a fine chromatin pattern. Mitoses were difficult to find; however, immunohistochemical Ki-67/MIB1 labeling indices were quite useful for evaluating proliferative activity, which ranged from 43.4 to 99.0%.

CONCLUSIONS

Our study showed the diagnostic potential of using biopsy specimens for large cell neuroendocrine carcinoma, and we herein proposed more simplified diagnostic criteria for possible large cell neuroendocrine carcinoma in practical diagnostic use.

Immunohistochemistry of cytokeratins 7, 8, 17, 18, and 19, and GLUT-1 aids differentiation of desmoplastic malignant mesothelioma from fibrous pleuritis

It is difficult to distinguish desmoplastic malignant mesothelioma (DMM) from fibrous pleuritis (FP). We investigated the utility of immunohistochemistry as a way of differentiating between DMM and FP. We examined 11 DMMs and 46 FPs with the aid of antibodies against 18 cytokeratin (CK) subtypes, calponin, caldesmon, desmin, and GLUT-1. The best sensitivity and specificity cut-off values in the receiver operating characteristic curves (ROC) for CKs 7, 8, 17, 18, and 19, and GLUT-1 were each above 60%. When cases with either DMM or FP were partitioned by the staining score associated with the best sensitivity and specificity cut-off values in ROC, the incidence of a positive expression for CKs 7, 8, 17, 18, and 19, and GLUT-1 was significantly higher in DMM than in FP. In conclusion, immunohistochemistry for CKs 7, 8, 17, 18, and 19, and GLUT-1 may be useful, alongside histological characteristics, for separating DMM from FP.

Involvement of knob heterochromatin in mitotic abnormalities in germinating aged seeds of maize

Seeds of three inbred lines of maize, with contrasting numbers of heterochromatic knobs and stored under two different ageing treatments, were analyzed for the occurrence of abnormalities at mitotic anaphase in root meristems 3, 7, 21,42, and 56 days after germination, and in root meristems of their freshly harvested selfed progeny. The largest category of detectable aberrations involved breakage of knobbed chromosome arms. We have obtained evidence that knob heterochromatin plays a central role in the origin of primary chromosome bridges. The initial event responsible for the occurrence of breakages and lagging chromosomes was characterized by the nondisjunction of newly replicated sister chromatids, which was observed to occur preferentially at the knob level. Such configurations, and all the other types of abnormalities (as for example, lagging chromosomes, typical chromosome bridges, fragments, and micronuclei), were observed at decreasing frequencies throughout root growth. Nevertheless, we have detected the occurrence of breakage-fusion-bridge cycles that were initiated by broken chromosomes. The relationship between late-replicating DNA in maize knob heterochromatin and the vulnerability of such regions to breakage is discussed. Our observations suggest a similarity between the mechanisms involved or associated with the origin of the described abnormalities and those reported to occur in cultured maize cells.

Correlations between serial pro-gastrin-releasing peptide and neuron-specific enolase levels, and the radiological response to treatment and survival of patients with small-cell lung cancer

INTRODUCTION

To investigate whether decrease in the serum levels of pro-gastrin releasing peptide (ProGRP) and neuron-specific enolase (NSE) were correlated with the radiological response in patients with small-cell lung cancer (SCLC).

METHODS

Of the 196 patients, we retrospectively reviewed 118 patients elevated baseline levels of ProGRP and NSE prior to the initial therapy (IT) who survived for more than 1 month. The radiological response was assessed by Response Evaluation Criteria in Solid Tumors (RECIST 1.1).

RESULTS

Decrease in the serum ProGRP was strongly correlated with the decrease of the sum of the tumor diameters (SOD) before the third course (ρ=0.50) and after the fourth course (ρ=0.42) of IT. Decrease in the serum NSE was weakly correlated with the decrease of the SOD after the fourth course (ρ=0.27), but not before the third courses (ρ=0.22). In the receiver operating characteristic (ROC) curves predicting 1-year survivors, the area under the curve (AUC) for percent changes in serum ProGRP before the third course were significantly larger than those for NSE (0.714 vs. 0.527, p=0.004).

CONCLUSIONS

Percent changes in serum ProGRP showed better correlation to SOD and prognostic impact than that of NSE.

A clinicopathological and immunohistological re-evaluation of adenosquamous carcinoma of the lung

Since the World Health Organization histological criteria were published in 1999, several studies have focused on adenosquamous carcinoma of the lung. Therefore, we aimed to clinicopathologically re-evaluate this tumor using immunohistochemical methods. In our hospital, there have been 21 surgically resected adenosquamous carcinomas. The frequency of adenosquamous carcinoma was 1.9% and the clinical data including the patient prognosis data obtained in this study were similar to those reported previously. A fluorodeoxyglucose positron emission tomography study first revealed that the median maximum standardized uptake value of adenosquamous carcinoma was 9.3 and ranged from 2.0 to 24.5. According to the results of immunohistochemical staining for thyroid transcription factor-1 (TTF-1) and p63, adenosquamous carcinomas were divided into four subgroups: group 1, TTF-1+ and p63+ (10 cases); group 2, TTF-1- and p63+ (six cases); group 3, TTF-1+ and p63- (three cases); and group 4, TTF-1- and p63- (two cases). Of the six group 2 tumors, three were composed of unique solid nests with mucin-filled cysts and showed characteristic p63 expression, which might suggest a special type of adenosquamous carcinoma. Immunohistochemical analysis of TTF-1 and p63 expression shows that adenosquamous carcinoma is composed of diverse tumor groups, for which the biological and histogenetic nature further needs to be clarified.

Quantification of umu genotoxicity level of urban river water

In recent years, the request of environmental safety management for carcinogenic substances, mutagenic substances and/or reproductive toxicity substances (CMR) has increased. This study focused on clarifying the genotoxicity level of environmental water and its release source by using the umu test provided in ISO13829. Although a genotoxicity index "induction ratio (IR)" is used in ISO13829, we normalised it to make it possible to compare various environmental water quantitatively to each other as a new index "genotoxic activity (GA=(IR-1)/Dose)". Sample water was collected and concentrated to 100 times or 1,000 times by a solid phase extraction method. As the test results, it was found that GA level in actual river water varied widely from less than the determination limit of 23 [1/L] to 1,100 [1/L] by quantitative comparison, and the value was also equivalent to more than 50 times the level of tap water. The GA level of household wastewater was not so high, but the levels of treated water from wastewater treatment plant (WTP) were from 220 [1/L] to 3,200 [1/L]. Raw sewage of some WTP shows high level genotoxicity. A part of genotoxicity substances, for example 50%, could be removed by conventional wastewater treatment, but it was not enough to reduce the water environmental load of genotoxicity.

Chlorination by-products of fenitrothion

The mutagens produced through chemical reaction between chlorine and the insecticide fenitrothion were studied by using a quadrupole GC-MS. The mutagenicity and the mutagen formation potential (MFP) of the identified by-products were evaluated by the Ames assay (preincubation method) using Salmonella typhimurium TA100 without exogenous activation by S9 mix (TA100-S9). Before conducting GC/MS analyses, six compounds were presumed to be produced in chlorinated fenitrothion. These compounds were confirmed to be produced by the GC/MS analyses, but none of them were mutagenic. One of the chlorination by-products, 3-methyl-4-nitrophenol, has 19 times greater MFP than that of fenitrothion. This result suggests that a major mutagen in chlorinated fenitrothion will be produced via a chemical reaction between chlorine and 3-methyl-4-nitrophenol.

Alveolar soft part sarcoma of the larynx: a case report of an unusual location with immunohistochemical and ultrastructural analyses

BACKGROUND

Alveolar soft part sarcoma (ASPS) is a rare mesenchymal neoplasm of uncertain origin. In this article, we report a case of ASPS occurring in the larynx, an extremely rare location for this rather unusual tumor.

METHODS AND RESULTS

The patient was a 34-year-old Japanese woman who requested an examination for hoarseness. The tumor showed a proliferation of large polygonal cells with periodic-acid-Schiff-positive diastase-resistant intracytoplasmic granules, arranged in an alveolar growth pattern. The cytoplasm of the tumor cells was eosinophilic. Tumor cells were positive for vimentin and titin. Nuclear immunoreactivity for TFE3 was observed, and the Ki-67 labeling index was 14.7%. Ultrastructurally, electron-dense rod-shaped crystals were infrequently observed in the cytoplasm. This case was finally diagnosed as ASPS of the larynx.

CONCLUSION

We discuss the histogenesis and differential diagnosis of ASPS with immunohistochemical and ultrastructural findings. TFE3 immunohistochemistry was found to be a very useful marker for the diagnosis of ASPS.

Cystadenoma of the palate: immunohistochemistry of mucins

Cystadenoma is a relatively rare benign epithelial tumor of the salivary glands, and described herein is an additional case. A 51-year-old Japanese man had noticed a mass of the left hard palate 25 years previously. Macroscopically, the resected specimen was a multicystic lesion. Histologically, the tumor was composed of bilayered columnar epithelium with cystic change and partial solid growth of glandular structures with clear cells. The tumor cells had mild cellular atypia, but the tumor lacked papillary growth and a fibrous capsule. Immunohistochemistry was positive for cytokeratins, epithelial membrane antigen, MUC1, MUC4 and MUC6, but negative for myoepithelial markers, MUC2, MUC5AC and MUC5B. Such MUC expression patterns suggested that cystadenoma occurs from excretory ducts.

Optimal extent of lymph node dissection for T1 gastric cancer, with special reference to the distribution of micrometastasis, and accuracy of preoperative diagnosis for wall invasion

BACKGROUND/AIMS

Preoperative diagnosis for wall invasion and lymph node metastasis is sometimes difficult in T1 gastric cancer. Optimum dissection extent of lymph nodes for T1 gastric cancer was studied from the aspect of subclassification of wall invasion and lymph node metastasis including micrometastasis.

METHODOLOGY

184 patients with cT1 or pT1 gastric cancer were studied. The grade of clinical wall invasion (cT) and clinical lymph node status (cN) were diagnosed by endoscopy and computed tomography or intraoperative findings. Lymph node metastasis (pN) was studied by hematoxylin and eosin staining and immunohistochemistry (IHC).

RESULTS

In 79 cM tumors, 60 (75.9%) were diagnosed as pM. In 88 cSM tumors, 42 (47.7%) were diagnosed as pSM. In 94 pM gastric cancers, micrometastases were found in two patients (2.1%) and in N1 stations. Two (1.9%) of 70 pSM cancers had micrometastasis in No. 7, 8a and 12a stations. Lymph node metastasis (pN) correlated significantly with the depth of tumor invasion, lymphatic invasion and venous invasion. Regarding the pN2 stations, one (1.1%) of 94 pM tumors had lymph node metastasis in No.7 station, and 9 (12.9%) of 70 pSM tumors had nodal involvement in No.7, 8a, 11p, 12a and 14v stations. All eight pN+/cM tumors were diagnosed as nN0 and four (1.4%) of 23 pN+/cSM tumors were correctly diagnosed as pN+. In contrast, 8 (9.9%) of 81 cN0/cM tumors and 19 (24.1%) of 79 cN0/cSM tumors had histological lymph node metastasis (pN+).

CONCLUSIONS

Accuracy of the clinical diagnosis of lymph node metastasis is very low. Accordingly, prophylactic lymph node dissection is recommended even for cT1 and cN0 tumors. For cN0/cM cancer, D1+No.7 is recommended. D1+No.7, 8a, 9, 11p is recommended for cSM cancer, located in U or M region and additional dissection of No. 14v is recommended for cSM cancer located in L region.

Primary nasopharyngeal mucoepidermoid carcinoma in Japanese patients: two case reports with histochemical and immunohistochemical analysis and a review of the literature

Mucoepidermoid carcinoma is a common neoplasm of the salivary glands. Salivary gland-type neoplasms are very rare in the nasopharynx, and there are only few reports on mucoepidermoid carcinoma of the nasopharynx. Two additional cases of mucoepidermoid carcinoma arising from the nasopharynx are reported here. Case 1: the patient was a 57-year-old Japanese woman who had bloody sputum. Case 2: the patient was a 51-year-old Japanese woman who underwent resection of a nasopharyngeal tumor. Histologically, both tumors were also low-grade mucoepidermoid carcinomas with clear cells. Histochemically, the gland-like nests and mucous cells were positive for mucin staining. Immunohistochemically, the lesions were positive for cytokeratins (CKs), p63, and MUC1, but negative for alpha-smooth muscle actin and EBER mRNA. The Ki-67 labeling indices of the two tumors were 10.4% and 4.3%, respectively. The two present cases and a review of the English literature indicate that salivary gland-type neoplasms arising from the nasopahrynx are extremely rare. The prognosis of salivary gland-type carcinomas of the nasopharynx is still unknown.

Telomere Length, Telomerase Activity, and Expressions of Human Telomerase mRNA Component (hTERC) and Human Telomerase Reverse Transcriptase (hTERT) mRNA in Pulmonary Neuroendocrine Tumors

BACKGROUND

Telomeres are important for chromosome structure and function, protecting them against degradation. However, few studies have examined telomeres in pulmonary neuroendocrine (NE) tumors.

METHODS

We investigated deparaffinized sections obtained from 70 primary NE lung tumors [34 typical carcinoids (TCs), 10 atypical carcinoids (ACs), 16 large cell neuroendocrine carcinoma (LCNECs) and 10 small cell lung carcinomas (SCLCs)].

RESULTS

Positive expressions of human telomerase mRNA component (hTERC) and human telomerase reverse transcriptase (hTERT) mRNA were recognized, respectively, in 58% and 74% of TCs, and in 100% and 100% of ACs, LCNECs and SCLCs. Alteration of telomere length was greater in both LCNECs and SCLCs than in TCs. Telomerase activity was detected in LCNECs, but not in TCs. By the reverse-transcriptase polymerase chain reaction (RT-PCR), hTERC mRNA was detected in 100% of LCNECs and TCs examined, while hTERT mRNA was detected in 67% of LCNECs, but not at all in TCs.

CONCLUSIONS

These results suggest that alterations in telomere length, telomerase activity, and the expression of hTERT mRNA may (i) play roles in pathogenesis in pulmonary neuroendocrine tumors, and (ii) be a useful tool for differential diagnosis between TCs and LCNECs.

Malignant pleural mesothelioma in a 14-year-old boy with right aortic arch

We report successful surgery for malignant pleural mesothelioma (MPM) in a 14-year-old boy with right aortic arch. Pleural biopsy by video-assisted thoracic surgery yielded a diagnosis of MPM, epithelial type. As the disease was not changed after combination chemotherapy with three cycles of cisplatin and gemcitabine, we performed left extrapleural pneumonectomy, including resection of the pericardium and diaphragm for MPM, and aortopexy for right aortic arch. The postoperative course was uneventful, and the patient has remained alive without disease for 10 months postoperatively.

Runx2 expression is associated with pathologic new bone formation around radicular cysts: an immunohistochemical demonstration

BACKGROUND

Radicular cysts are the most common cysts in human jaw bones. These lesions induce bone remodeling of the surrounding alveolar bones, which was termed 'condensing osteitis', and was suggested to be related to cells of the osteoblastic lineage. The Runx2 (core-binding protein [cbfa]1/polyoma enhancer-binding protein [pebp]2alphaA) was shown to be a DNA-binding transcriptional molecule expressed in osteoprogenitor cells.

METHODS

We confirmed the specificity of anti-Runx2 antiserum, using Western blotting analysis. We investigated the expression and localization of Runx2 in 32 radicular cyst cases with bone tissue fragments, immunohistochemically.

RESULTS

Signals for Runx2 were seen in 18 cases (56.3%) of radicular cysts with bone formation. These signals were immunolocalized in the nuclei of the spindle-shaped osteoprogenitor cells in the cyst walls, whereas only a few signals were seen in the cuboidal osteoblastic cells near the fibrous bones. Signals for type I collagen were immunolocalized in the dense collagen fibers in the cyst walls and in the matrix of the fibrous bone around the radicular cysts, whereas no signals were seen on the inner portions with inflammatory cell infiltration of the cyst walls. Very weak signals for transforming growth factor (TGF)-beta1 were infrequently seen in the osteoblasts of the fibrous bone, whereas signals for TGF-beta2 were observed in young osteocytes in the fibrous bones, in B-cell lymphocytes infiltrating into the inner portions, and on the cellular membranes of the lining epithelium.

CONCLUSIONS

The nuclear expression of Runx2 in spindle-shaped cells in the outer portions may play an essential role in the induction of fibrous bone tissue around radicular cysts. TGF-beta2 may play a role in the production of type I collagen, which acts as a template for pathologic new bone formation, in radicular cysts.

Gastric large cell neuroendocrine carcinomas: a distinct clinicopathologic entity

The current histologic classifications of gastric cancers define only carcinoids and small cell carcinomas in the neuroendocrine (NE) category. This study aimed to characterize the histologic and clinical features of high-grade gastric NE carcinomas of nonsmall cell type, tentatively named large cell neuroendocrine carcinoma (LCNEC). Tumors with histologic features suspicious of NE differentiation were selected by a histologic review of 2835 resected gastric cancers, and those with a NE phenotype in > 50% and 1% to approximately 50% tumor cells assessed by expressing chromogranin A and/or synaptophysin were defined as LCNEC and adenocarcinoma with neuroendocrine differentiation (ACNED), respectively. One hundred ninety-nine tumors were selected and of the 109 positive for chromogranin A and/or synaptophysin, 42 and 44 met the criteria for LCNEC and ACNED, respectively. Generally, LCNECs demonstrated less predominant NE morphology than carcinoids, and could be roughly divided into solid (30 cases), tubular (7 cases), and scirrhous (5 cases) subtypes with reference to their main growth pattern. The prognosis of LCNECs was significantly worse than that of conventional adenocarcinomas (P < 0.0001). Thus, this study shows that the spectrum of gastric NE tumors is broader than has previously been recognized and LCNEC is not only a distinct histopathologic entity, but also a distinct clinical entity. Furthermore, the prognosis of ACNEDs was also significantly worse than that of adenocarcinomas (P < 0.0001), and some ACNEDs might actually have been LCNECs, and survival analysis showed that > 20% positivity of NE markers could be enough to characterize LCNEC, as long as light microscopic NE morphology was present in the tumor.

Characteristics of loss of heterozygosity in large cell neuroendocrine carcinomas of the lung and small cell lung carcinomas

Large cell neuroendocrine carcinoma (LCNEC) of the lung is a new entity. Besides morphological characteristics, its molecular biological features have been investigated by many researchers and compared to those of other neuroendocrine carcinomas, small cell lung carcinoma (SCLC) and carcinoid tumor (CT). However, there are few reports that show the significantly different genetic characteristics between them. The purpose of the present paper was to study the frequency of loss of heterozygosity (LOH) at chromosome 3p (3p14.2) in 38 neuroendocrine carcinomas of the lung (13 LCNEC, 11 SCLC and 14 CT) and 10 large cell carcinomas (LCC). The frequencies of LOH at 3p14.2 were 69.2% in LCNEC, 81.8% in SCLC, 50.0% in LCC and 7.14% in CT. Those at 22q13.3 were 30.8% in LCNEC, 72.7% in SCLC, 45.5% in LCC and 7.14% in CT. In particular, the frequency of SCLC with LOH at both 3p14.2 and 22q13.3 (63.6%) was significantly higher than that of LCNEC (15.4%). LCNEC and SCLC had different characteristics of LOH patterns at 3p14.2 and 22q13.3. The combined analysis of the LOH at 3p14.2 and 22q13.3 is thought to be useful for differential diagnosis between LCNEC and SCLC.

Evaluation of lymphatic invasion in primary gastric cancer by a new monoclonal antibody, D2-40

Lymphatic invasion is known as an independent predictor of lymph node metastasis in gastric cancer. However, the diagnosis of lymphatic invasion is sometimes difficult by hematoxylin-eosin (H&E) staining. Immunostaining using D2-40 was performed to study the distribution of lymphatic vessel and lymphatic invasion in a series of 78 primary gastric cancers. D2-40 showed specific staining for the lymphatic vessels, but not for blood vessels. The lymphatic invasion was most frequently found in the upper half of submucosal layer. Positive rate of lymphatic invasion by H&E staining was 27% (21/78), and that by D2-40 was 44% (34/78). Lymphatic invasion on H&E staining was diagnosed as false negative in 17 (21.8%) of 78 primary gastric cancers and false positive in 4 (5.1%) of 78 primary gastric cancers. Sensitivity for lymph node metastasis by the lymphatic invasion diagnosed by D2-40 was significantly higher (89%, 24/27) than by H&E staining (41%, 11/27). These results suggest that the diagnosis of lymphatic invasion by D2-40 is more sensitive than H&E staining. Sensitivity for the prediction of lymph node metastasis from the lymphatic invasion status in primary tumor by D2-40 was significantly higher than by H&E staining. Based on our results, we recommend the use of D2-40 immunoreactions for the routine evaluation of lymphatic invasion in gastric cancer.

Differential expression of N-cadherin and E-cadherin in normal human tissues

E-cadherin, which expressed in various epithelial tissues, is important for the maintenance of normal epithelial phenotypes. However, the distribution of N-cadherin in normal human tissues has not been defined systemically. In the present study, we employed a sensitive, reliable immunohistochemical detection system for N-cadherin on formalin-fixed, paraffin-embedded tissue sections, and succeeded in demonstrating N- and E-cadherin protein expressions and their distribution in normal human tissues. E-cadherin immunoreactivity was detected in all the epithelial tissues examined, except for the adrenal cortical cells and granulosa cells. N-cadherin was selectively expressed on epithelial cells of the thymus, pituitary, pancreas, liver, adrenal, endometrium of the uterus, ovary, and stomach as well as in neuronal tissues. Double immunostaining revealed that N-cadherin expression was closely associated with the hormone-producing ability of cells in the pancreas and pituitary. Thus, this study indicated the possibility that N-cadherin is selectively expressed in relation to hormonal regulation in some organs and plays different functions in different situations. The method presented here should prove useful for the further investigation of the N-cadherin expression and function in several disease conditions on formalin-fixed, paraffin-embedded archival tissues.

Primary adenoid squamous cell carcinoma of the oral cavity

Adenoid squamous cell carcinoma (ASCC) is an uncommon but well-recognized variant of squamous cell carcinoma that was first described by Lever in 1947. ASCC has been reported to originate in the sun-exposed skin of the head and neck and in other sites. An additional case of ASCC is reported here. The patient was a 64-year-old Japanese woman who requested examination of a reddish lesion on the left floor of the mouth. The biopsy material was diagnosed as squamous cell carcinoma. Clinical examination showed a well-circumscribed, 20 x 10 mm-sized lesion, which was categorized as cT2cN0cm 0. Tumor resection was therefore performed. Histologically, most parts of the lesion were conventional squamous cell carcinoma in situ, but the invasive part consisted of ASCC with gland-like or reticular appearance. The latter part was negative for mucin staining. Immunohistochemically, this lesion was positive for pancytokeratin, high-molecular-weight keratin, cytokeratin (CK) 7/8, CK19, E-cadherin and p53, but negative for vimentin, CK20, and S-100 protein. The Ki-67 labeling index was 50.3% in the ASCC part and 34.5% in the carcinoma in situ part. These findings and a review of the literature indicate that a gland-like feature of ASCC is associated with the loss of cell adhesion in the center of the cancer nests, and it can be confirmed simply by mucin staining to be neither an adenosquamous carcinoma nor ductal involvement of conventional squamous cell carcinoma.

A larval medaka (Oryzias latipes) acute toxicity assay combined with solid-phase extraction to efficiently determine the toxicity of organic contaminants in river water

Using a larval medaka (Oryzias latipes) acute toxicity assay combined with solid-phase extraction, we proposed a method for efficiently determining the fish toxicity of organic contaminants in river water. Organic toxicants were 10, 20, 50 and 100-fold concentrated from 4 L of the sample with adsorption cartridges. The lethal effect was observed by exposing every ten individuals of 48-72 h old larval medaka to 20 mL of each solution for 48h. The median lethal concentration rate (LCR50) was used as an indicator for the toxicity. With the developed toxicity test method, more than seven times difference was found in the LCR50 of the river water samples. LCR50 distribution profiles were compared with 125 samples in two typical rivers. The result revealed a lower toxicity level in the mainstream than in the confluences, and a lower toxicity level in Sagami River than in Ayase River. LCR50 proved unique as a toxicity indicator, which was impossible to speculate from the conventional water quality indicator of the dissolved organic carbon concentration. As an effective screening test for priority settings, the method can help us with an efficient planning for the environmental investigation and management.

Neuroendocrine Neoplasms of the Lung: A Prognostic Spectrum

Purpose

Neuroendocrine (NE) tumors of the lung include typical carcinoid (TC), atypical carcinoid (AC), large-cell NE carcinoma (LCNEC), and small-cell lung carcinoma (SCLC). Their clinicopathologic profiles and relative grade of malignancy have not been defined.

Patients and Methods

From 10 Japanese institutes, 383 surgically resected pulmonary NE tumors were collected. The histologic diagnosis was determined by the consensus of a pathology panel consisting of six expert pathologists as TC, AC, LCNEC, or SCLC on the basis of the WHO classification, and its relationship to clinicopathologic profiles was analyzed.

Results

Of the 383 tumors, 18 were excluded because of an improper specimen. The pathology panel reviewed the remaining 366 tumors, and a diagnosis of NE tumor was made in 318 patients (87.4%); 55 patients had TC, nine had AC, 141 had LCNEC, and 113 had SCLC. The 5-year survival rates of patients with all stages were as follows: 96.2% for TC, 77.8% for AC, 40.3% for LCNEC, and 35.7% for SCLC. There was significant prognostic difference between TC and AC as well as between AC and LCNEC+SCLC. However, there was no difference between LCNEC and SCLC, and their survival curves were superimposed. The multivariate analysis indicated that histologic type, completeness of resection, symptoms, nodal involvement, and age were significantly prognostic.

Conclusion

The grade of malignancy of NE tumors was upgraded in the following order: TC, AC, LCNEC, and SCLC. No prognostic difference was noted between LCNEC and SCLC. The high-grade NE histology uniformly indicated poor prognosis regardless of its histologic type.

Pituicytoma-Two Case Reports-

Pituicytoma is a rare tumor in the sellar or suprasellar region with distinct histological characteristics of glial neoplasm. A 42-year-old woman presented with a history of amenorrhea and vertigo, and a 62-year-old woman presented with mild headache. Both patients had mild hyperprolactinemia and one had mild anterior pituitary dysfunction. They underwent transcranial partial resection of a suprasellar tumor. The tumors were characterized by storiform pattern of elongated cells immunoreactive for S-100 protein and glial fibrillary acidic protein. Ultrastructural study showed abundant cytoplasmic intermediate filaments and tumor/blood vessel basal lamina, but no desmosomes between tumor cells. The residual tumors showed no changes in size without adjuvant therapy at 56 and 18 months after surgery. Pituicytoma is a glial neoplasm of adults with low proliferative activity. Patients often present with visual symptoms or anterior pituitary dysfunction. Symptoms and signs of neurohypophysis are rare. Neuroimaging reveals an intra- or suprasellar mass with non-specific features. The prognosis and role of adjuvant therapy remain unclear for this discrete noninfiltrative glioma.

Influence of micrometastasis on N stage in gastric cancer and clinical application

In order to evaluate the real extent of lymph node metastasis (LNM) in gastric cancer, an immunohistochemical (IHC) analysis was performed. We examined 11173 lymph nodes removed from 355 patients with all stages of gastric carcinoma. Tissue preparations were stained with cytokeratin 18, monoclonal antibody against cytokeratin. Micrometastases were found in 2.5% of the lymph nodes and in 31.3% of patients. The incidence of the patients with LNM increased to 9.1% in T(1m) (n = 99), 31.6% in T(1sm) (n = 95, 23.1% in sm1, 34.8% in sm2), 66.7% in T2 (n = 108, 48.8% in mp, 76.5% in ss), 88.1% in T3 (n = 42), and 90.9% in T4 (n = 11) lesions. Upstage was identified in 8.5% of patients: 6.7% in T1 (4.0% in m, 7.7% in sm1, 10.1% in sm2), 14.8% in T2 (20% in mp, 11.8% in ss), 2.4% in T3, and 0% in T4. Factors related to LNM were: tumor size and lymphatic invasion in mucosal lesions; only lymphatic invasion in submucosal lesions; size and depth of tumor, and lymphatic invasion in T2 lesions. In conclusion, the incidence of micrometastasis in regional lymph nodes was higher than we imagined in T1 lesions, more than D1 lymphadenectomy for sm1 and selected cases of mucosal cancer, and D2 lymphadenectomy for sm2 are necessary.

Rescue from Dwarfism by Thyroid Function Compensation in rdw Rats

The rdw rat was initially reported as having hereditary dwarfism caused by pituitary dysfunction. Subsequent studies on the rdw rat, however, have demonstrated that the primary cause of rdw dwarfism is present in the thyroid gland but not in the pituitary gland. The primary cause of rdw rat disorders is a missense mutation of the thyroglobulin (Tg) gene by a one-point mutation. In the present study, we attempted to rescue the dwarfism of the rdw rats using a diet supplemented with thyroid powder (T-powder) and a thyroid graft (T-graft). The infants of the rdw rat were successfully raised to a mature stage body weight, accompanied by elevation of serum growth hormone (GH) and prolactin (PRL), by the T-powder. Furthermore, the T-graft successfully increased the body weight with fertility. The serum GH and PRL levels in the T-graft rdw rat significantly increased. The serum thyroid-stimulating hormone (TSH) levels in the T-graft rdw rat were significantly decreased but were significantly higher than those in the control rat. The GH and PRL mRNA expression in the rdw rat with the T-graft was virtually the same as that of the control, but the TSH beta mRNA differed from that of the control rats. Thus, the dwarfism in the rdw rat is rescued by thyroid function compensation, such as that afforded by T-powder and T-graft.

Divergent cyclin B1 expression and Rb/p16/cyclin D1 pathway aberrations among pulmonary neuroendocrine tumors

A total of 111 pulmonary neuroendocrine tumors comprising 13 typical carcinoids, five atypical carcinoids, 44 large-cell neuroendocrine carcinomas and 49 small-cell carcinomas were immunohistochemically studied for dysregulated cyclin B1 expression and disruption of the Rb/p16/cyclin D1 pathway (Rb pathway), and the results were correlated with tumor proliferation activity and clinical outcome. Overexpression of cyclins B1 and D1, respectively, was detected in no and 15% typical carcinoids, 20 and 20% atypical carcinoids, 84 and 32% large-cell neuroendocrine carcinomas, 84 and 10% small-cell carcinomas. Loss of Rb and p16 expression, respectively, was observed in no and 14% typical carcinoids, no and 40% atypical carcinoids, 49 and 18% large-cell neuroendocrine carcinomas, 84 and 8% small-cell carcinomas. In summary, 29% typical carcinoids, 20% atypical carcinoids, 78% large-cell neuroendocrine carcinomas and 93% small-cell carcinomas had Rb pathway aberrations. Rb pathway aberration was mostly attributed to Rb loss in small-cell carcinomas, while p16 loss and/or cyclin D1 overexpression besides Rb loss also played an important role in large-cell neuroendocrine carcinomas, while cyclin D1 overexpression was the only cause of Rb pathway aberration in carcinoid tumors. Thus, both cyclin B1-associated G2/M arrest and Rb-mediated G1 arrest are consistently compromised in high-grade large-cell neuroendocrine carcinoma and small-cell carcinoma, but are generally intact or occasionally altered in carcinoid tumor; the mechanisms involved in Rb pathway aberration among the tumor categories are different, reflecting a genetic divergence among the individual tumor categories. Cyclin B1 expression closely correlated with the Ki-67 labeling index either in the individual tumor categories or overall tumors (P < 0.0001, r = 0.742), suggesting that cyclin B1 is one of the key factors regulating cell proliferation in pulmonary neuroendocrine tumors. Neither cyclins B1 and D1, Rb, p16, nor Ki-67 correlated with patient survival in individual tumor categories, suggesting that the prognostic significance of these factors is tumor-type specific.

Severe hypoglycemia and hypokalemia in association with liver metastases of gastric cancer

We report an 80-year-old man who presented with non-islet cell tumor hypoglycemia (NICTH) in association with hepatic recurrence of gastric cancer. His serum potassium was reduced from 3.9 to 3.1 mmol/l 5 weeks after gastrectomy, and he subsequently developed hypoglycemic coma. He was diagnosed as having NICTH because of the presence of serum big IGF-II and positive staining for IGF-II in gastric cancer cells obtained at surgery. A computed tomography showed multiple liver metastases. His hypoglycemia was refractory to steroid therapy. This case suggested that NICTH could develop in association with hepatic metastases of gastric cancer. Unexpected hypokalemia may be a manifestation of occult NICTH.

hASH1 expression is closely correlated with endocrine phenotype and differentiation extent in pulmonary neuroendocrine tumors

The human homolog 1 of the Drosophila neurogenic achaete-scute genes, hASH1, is specifically expressed in fetal pulmonary neuroendocrine cells and in some neuroendocrine tumor cell lines. However, no data have been gathered regarding its in vivo expression in tumors. hASH1 mRNA expression was investigated by in situ hybridization in 238 surgically resected lung carcinomas, and the correlations between hASH1 expression status and immunostaining results of neuroendocrine markers chromogranin A, neural cell adhesion molecule, gastrin-releasing peptide and calcitonin, and clinical outcome were analyzed. hASH1 expression was detected in 2/20 (10%) adenocarcinomas, 4/30 (13.3%) typical carcinoids, 11/13 (84.6%) atypical carcinoids, 38/67 (56.7%) large-cell neuroendocrine carcinomas and 56/78 (71.8%) small-cell carcinomas, respectively, but not in any squamous cell carcinoma (0/21) or large-cell carcinoma (0/9). The 2 hASH1+ adenocarcinomas also expressed multiple neuroendocrine markers. Thus, hASH1 expression was restricted to lung cancers with neuroendocrine phenotypes. However, not all neuroendocrine tumors expressed hASH1. Within the entities of large-cell neuroendocrine carcinoma and small-cell carcinoma, hASH1 expression correlated very closely with chromogranin A, gastrin-releasing peptide and calcitonin expression (P<0.0001, r=0.852), but was not related to neural cell adhesion molecule expression (P=0.8892), suggesting that hASH1 expression, at least in lung cancer, is associated with endocrine phenotype expression other than 'neuroendocrine differentiation' in a broad sense. The fact that hASH1 was virtually absent in almost fully differentiated typical carcinoids, but was expressed in most, if not all, less differentiated atypical carcinoids as well as large-cell neuroendocrine carcinomas and small-cell carcinomas, suggests that hASH1 expression in lung cancer imitates its early and transient expression in fetal development, and that hASH1 is instrumental in the establishment, but not in the maintenance, of a cellular endocrine phenotype. Finally, hASH1 expression correlated with a significantly shortened survival in small-cell carcinoma patients (P=0.041).

Recent Advances in MEN 1 Gene Study for Pituitary Tumor Pathogenesis

Evidence of multiple endocrine neoplasia type 1 (MEN1) is found in approximately 2.7% of patients with pituitary adenomas. The multicentricity of pituitary adenomas has not yet been proved. Prolactinomas are most frequent in MEN1 pituitary tumors. Pituitary tumors with MEN1 are larger in size and more aggressive than without MEN1. Heterozygous germline mutations of MEN1 gene are responsible for MEN1 disorders. Various types of mutations likely causing loss of the gene function have been identified throughout the entire region in patients with MEN1 and related disorders. However, the function of menin, the product of MEN1 gene, remains to be established. Neither mutation hot spot nor phenotype-genotype correlation has been established in classical MEN1. A number of recent studies suggest that somatic mutations in the MEN1 gene do not play prominent role in the pathogenesis of sporadic forms of pituitary adenoma.

Microtubule-associated protein-2 and class III beta-tubulin are expressed in extraskeletal myxoid chondrosarcoma

Extraskeletal myxoid chondrosarcoma is a rare soft tissue sarcoma of uncertain histogenetic origin. Because recent reports have indicated neural-neuroendocrine differentiation in some extraskeletal myxoid chondrosarcomas, we investigated 25 tumors for expressions of microtubule-associated protein-2 and Class III beta-tubulin, which are major components of microtubules and specifically localized in neurons and their derivatives. Immunohistochemical expression of microtubule-associated protein-2 and Class III beta-tubulin was studied in extraskeletal myxoid chondrosarcomas using formalin-fixed, paraffin-embedded tissues. Cytoplasmic expressions of microtubule-associated protein-2 and Class III beta-tubulin were detected in 21 (84%) and 13 (52%) of the 25 extraskeletal myxoid chondrosarcomas, respectively, although the number of positively stained tumor cells varied. Expression of the Class III beta-tubulin gene was also assessed in two immunohistochemically positive cases by in situ hybridization using an oligonucleotide probe specific for its transcript, and both cases showed expression of Class III beta-tubulin transcript. Another case was examined with immunoelectron microscopy, and immunogold particles for Class III beta-tubulin were localized to microtubular aggregates. Our data indicate that microtubules in extraskeletal myxoid chondrosarcoma are similar to those found in neurons, further supporting the concept that neural-neuroendocrine differentiation occurs in a significant number of extraskeletal myxoid chondrosarcoma.

Expression of AODEF, a B-functional MADS-box gene, in stamens and inner tepals of the dioecious species Asparagus officinalis L

Garden asparagus (Asparagus officinalis L.) is a dioecious species with male and female flowers on separate unisexual individuals. Since B- and C-functional MADS-box genes specify male and female reproductive organs, it is important to characterize these genes to clarify the mechanism of sex determination in monoecious and dioecious species. In this study, we isolated and characterized AODEF gene, a B-functional gene in the development of male and female flowers of A. officinalis. Southern hybridization identified a single copy of AODEF gene in asparagus genome. Northern blot analysis showed that this gene was specifically expressed in flower buds and not in vegetative tissues. In situ hybridization showed that during early hermaphrodite stages, AODEF gene was expressed in the inner tepal and stamen whorls (whorls 2 and 3, respectively), but not in the outer tepals (whorl 1), in both male and female flowers. In late unisexual developmental stages, the expression of AODEF gene was still detected in the inner tepals and stamens of male flowers, but the expression was reduced in whorls 2 and 3 of female flowers. Our results suggest that AODEF gene is probably not involved in tepal development in asparagus and that the expression of AODEF gene is probably controlled directly or indirectly by sex determination gene in the late developmental stages.

Diversity in expression and prognostic significance of G1/S cyclins in human primary lung carcinomas

Expression of cyclin A, cyclin E and cdk2 was examined immunohistochemically in 144 cases of primary non-small cell lung carcinoma to evaluate their prognostic value. Cyclin A was co-expressed with cdk2 in the proliferating cells, ie those showing positive Ki-67 staining. The labelling index (LI) of cyclin A revealed a positive correlation with the S-phase fraction and an inverse correlation with histological differentiation. Furthermore, high cyclin A LIs indicated a poor prognosis in all histological types. Cyclin E exhibited a characteristic staining pattern: in squamous cell carcinoma (SCC), differentiated cells without Ki-67 staining revealed cyclin E positivity with expression of cdk2. Conversely, in adenocarcinoma (AC), proliferating cells revealed cyclin E positivity. Cases of large cell carcinoma showed heterogeneous cyclin E staining patterns, unlike those of SCC or AC. Statistical analyses also revealed a marked contrast between SCC and AC. In AC, the LI of cyclin E was inversely correlated with histological differentiation and a high LI predicted a worse prognosis. In contrast, in SCC, the LI of cyclin E correlated positively with histological differentiation and better prognosis. However, the expression levels of cyclin E mRNA evaluated by quantitative RT-PCR were higher in poorly differentiated SCC and AC, suggesting that protein turnover plays a large role in determining cyclin E protein levels. Although the expression of cyclins was demonstrated to be diversely regulated depending on the histological type, the combined immunohistochemical analyses performed in this study on these proteins could be useful tools for evaluating patient prognosis in lung carcinomas.

Expression of Epstein-Barr virus-encoded small nuclear RNA 1 in Japanese nasopharyngeal carcinomas

An examination was made of the incidence of the Epstein-Barr virus (EBV) genome and its exact localization in 39 cases of nasopharyngeal carcinoma (NPC) in Japanese patients by means of in situ hybridization (ISH) with a digoxigenin-labeled Epstein-Barr virus-encoded small nuclear RNA 1 (EBER1) oligonucleotide probe. Hybridization signals were observed in the nucleus of tumor cells in all 39 NPCs, including keratinizing carcinomas. The signals varied greatly in intensity from case to case and even from cell to cell in the same tumor, but were recognized in most tumor cells in each case. Signals could occasionally be seen in limiting number of infiltrating small lymphocytes but were absent in all tumors of the tongue, midpharynx and hypopharynx. Combined immunohistochemistry-ISH studies indicated that EBER1 signals were restricted to tumor cells positive for cytokeratin. As a result of this study, it is now possible to perform large-scale retrospective analyses using routine formalin-fixed, paraffin-embedded tissue sections and to combine ISH for the EBV genome with immunohistochemistry for cytokeratin to determine the epithelial features of EBV genome-possessing cells. All NPCs were clearly shown to be EBV-infected, thus indicating that EBV is essential for the oncogenesis of NPCs.