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Tadao Nakazawa

Publications and source records attributed to Tadao Nakazawa.

11 recordsLinked to original sources
PubMed2006

Expression of aquaporin 3 (AQP3) in normal and neoplastic lung tissues.

Aquaporin 3 (AQP3) acts as the membrane channel of water and other small solutes and plays a major role in fluid homeostasis. To investigate the expression of AQP3 in normal and neoplastic lung tissues, we studied a series of 149 lung carcinoma tissues and 2 cell lines by immunohistochemistry, Western blotting, and reverse transcriptase-polymerase chain reaction. In normal lung tissues, immunohistochemical expression of AQP3 was demonstrated in bronchial basal cells, alveolar type II cells, bronchiolar epithelial cells, and secretory cells of submucosal glands. In lung carcinomas, AQP3 expression was observed in 59 (70.2%) of 84 adenocarcinomas. Squamous cell carcinoma and large cell carcinoma had rather low positive ratios (35.8% and 13.4%, respectively). No AQP3 expression was demonstrated in small cell carcinoma, pleomorphic carcinoma, or metastatic colon adenocarcinoma. In adenocarcinomas, AQP3 was detected in all tumors of bronchioloalveolar subtype. Papillary subtype also showed a higher positive ratio of AQP3 compared with that in acinar and solid with mucin subtypes. In addition, AQP3 expression was related to tumor differentiation and clinical stage in adenocarcinomas. Western blotting and reverse transcriptase-polymerase chain reaction analyses confirmed the expression of AQP3 protein and messenger RNA in cell lines and tissues of lung adenocarcinoma. We conclude that AQP3 is widely expressed in the normal respiratory tract and can play an important role in the maintenance of water homeostasis. In addition, lung carcinomas, especially adenocarcinomas, can produce AQP3, possibly in connection with their functional and/or biological nature, although the detailed mechanism of AQP3 expression in lung carcinomas remains to be clarified.

Adenocarcinoma↗
PubMed2005

RET gene rearrangements (RET/PTC1 and RET/PTC3) in papillary thyroid carcinomas from an iodine-rich country (Japan).

BACKGROUND: The frequency of RET rearrangements (RET/PTC) in papillary thyroid carcinomas varies significantly according to geographic area, with the greatest incidence reported in the Belarus region, which is iodine-deficient and was contaminated severely after the Chernobyl reactor accident, and with the lowest incidence in iodine-rich, nonirradiated Japan. The authors investigated the prevalence of RET/PTC in a large number of thyroid tumors from Japanese patients. METHODS: Fresh and paraffin embedded tumor tissues from 215 Japanese patients were examined for RET rearrangements (RET/PTC1 and RET/PTC3) by means of reverse transcriptase-polymerase chain reaction analysis, with primers flanking the chimeric region, followed by direct-sequence analysis. RESULTS: RET/PTC was found only in papillary carcinomas and was not observed in other histologic types of thyroid tumors. The overall frequency of RET/PTC in papillary carcinomas was 28.4%, with a greater frequency in younger patients, including 41.9% of younger patients age < 20 years, 27.6% of patients age 20-40 years, and 24.8% of patients age > 40 years. Among the patients in these 3 age groups, the prevalence rate of RET/PTC1 was similar, but RET/PTC3 was observed most frequently among patients age < 20 years. When the tumors were grouped further according to histologic subtypes, the prevalence of RET/PTC3 was greater in solid/solid-follicular papillary carcinomas than in classic papillary carcinomas. CONCLUSIONS: The results indicated that RET/PTC may be useful as a specific molecular marker for papillary thyroid carcinomas. Furthermore, its incidence in such tumors was not low in Japanese patients, and it seemed to be associated with patient age. Therefore, the current results raise questions regarding the belief that the frequency of RET/PTC differs geographically and is especially low in Japan.

Adult↗
PubMed2005

Stromal elastosis in papillary thyroid carcinomas.

Stromal elastosis, defined as dense aggregations of elastic fibers, is found in some neoplastic tissues especially in malignant tumors of the breast and lung. Although also found in thyroid tissue, stromal elastosis in thyroid neoplasms have received little attention. To clarify the histopathological significance of stromal elastosis in the thyroid, we examined neoplastic (n = 223) and hyperplastic (n = 82) thyroid tissues in conjunction with cancer tissues (n = 193) of various other organs. Stromal elastosis was observed as deposits of pale homogeneous material in hematoxylin and eosin stain, and distinctively highlighted by elastic-van Gieson's stain. On immunohistochemical examination, elastin and tropoelastin were confirmed in these deposits. Stromal elastosis was found in 66% of papillary thyroid carcinomas (PTCs), although it was not identified in other histological types of thyroid neoplasms. In PTCs, deposits of elastic fibers varied in size and shape, and were more frequently distributed in the periphery of the tumor tissue. The histological subtypes of PTC varied in prevalence of elastosis with the follicular variant's (9%) prevalence being significantly lower than that of the classical type (72%). The frequency of stromal elastosis in PTCs was very similar to the frequencies in breast and lung adenocarcinomas, and higher than the frequencies in carcinomas of other organs. In conclusion, our results suggest that stromal elastosis is a characteristic histological finding of PTCs, presumably associated with their growth pattern and/or histological architecture. It is, therefore, reasonable to propose that stromal elastosis is an ancillary feature in the histopathological diagnosis of PTCs.

Carcinoma, Papillary↗
PubMed2005

Mucinous carcinoma (poorly differentiated carcinoma with extensive extracellular mucin deposition) of the thyroid: a case report with immunohistochemical studies.

We report on a case of mucinous carcinoma of the thyroid in an 82-year-old Japanese woman. The 3 x 2 x 2-cm thyroid tumor located in the patient's right lateral lobe was soft and yellowish gray on the cut section. Microscopically, the tumor was composed entirely of strands or solid clusters accompanied by extensive extracellular mucin. Extracellular mucin was positive with Alcian blue stain and negative with periodic acid-Schiff stain. Immunohistochemically, the tumor cells were positive for thyroglobulin, thyroid-specific transcription factor 1, and low-molecular-weight cytokeratin but negative for carcinoembryonic antigen, calcitonin, and high-molecular-weight cytokeratin. The MIB-1 labeling index was rather high (11%), and immunoexpression of p53 was detectable in the nuclei of carcinoma cells. From these findings, we classified the present tumor as a mucinous carcinoma of the thyroid (poorly differentiated thyroid carcinoma producing massive extracellular mucin). The patient died of multiple metastases 4 years after the initial operation.

Adenocarcinoma, Mucinous↗
PubMed2005

Endocervical adenocarcinomas associated with lobular endocervical glandular hyperplasia: a report of four cases with histochemical and immunohistochemical analyses.

We report on four cases of endocervical adenocarcinoma associated with lobular endocervical glandular hyperplasia using histochemical and immunohistochemical analyses. The patients ranged in age from 59 to 67 years (mean 62 years). Chief complaints were watery vaginal discharge in two cases, genital bleeding in one and no subjective symptoms in one. Cytological examinations of the cervical smears revealed adenocarcinoma cells and benign-looking glandular cells with intracytoplasmic golden-yellow mucin in all cases. Radical hysterectomy was performed in three patients, and simple total hysterectomy was performed in one. From surgical specimens, three tumors were diagnosed as mucinous adenocarcinoma and one was adenocarcinoma in situ. All adenocarcinomas were located proximally on the cervix, and did not involve the transformation zone. Adjacent to carcinoma tissues in the cervix, lobular endocervical glandular hyperplasia was detected. The cells of lobular endocervical glandular hyperplasia were dominantly positive with neutral mucin, and immunohistochemistry revealed that these cells had prominent pyloric gland mucin (HIK1083). Focal immunopositivity for pyloric mucin was also observed in three adenocarcinomas. Either CEA or p53 were immunopositive in all adenocarcinomas and negative in the tissues of lobular endocervical glandular hyperplasia. Histopathological features of the present cases suggest that some endocervical adenocarcinomas may originate from lobular endocervical glandular hyperplasia.

Adenocarcinoma↗
PubMed2004

Mixed papillary adenocarcinoma and transitional cell carcinoma of the uterine cervix.

A mixed papillary adenocarcinoma and transitional cell carcinoma (MAcTcc) was discovered in the uterine cervix of a 38-year-old woman. A condylomatous papillary lesion was found in the uterine cervix during a colposcopic study and histopathological examination showed that the tumor was composed of two different neoplastic subtypes. One was an adenocarcinoma (AC) component showing papillary and tubular structure with endocervical and intestinal differentiation; the other was a transitional cell carcinoma (TCC) component showing papillary excrescence mimicking papillary TCC of urothelial origin. To characterize the tumor, an immunohistochemical study of cytokeratins (CK) was performed. The AC component showed immunoreactivities similar to conventional adenocarcinomas: positive immunoreactivity of low-molecular-weight cytokeratins 7, 8 and 19, and negative immunoreactivity of CK20 and high-molecular-weight cytokeratin (34betaE12). The lower epithelial layer of the TCC component showed different immunoreactivity, but the superficial epithelial layer had similar immunohistochemical findings to the AC component. These findings indicate that the TCC component had the cellular character of AC rather than that of TCC or squamous cell carcinomas. This is thought to be the first report of a MAcTcc of the uterine cervix.

Adenocarcinoma, Papillary↗
PubMed2003

Morphological abstraction of thyroid tumor cell nuclei using morphometry with factor analysis.

Various morphonuclear studies by digital image analysis have successfully been applied to quantify the nuclear morphology, including chromatin distribution pattern, in cytology of various organs; however, the majority of past reports have not shown correlation between the quantitative data by digital image analysis and cytological findings in practical diagnosis. In this report, we present the usefulness of morphological abstraction to combine the objective data and subjective observation in cytological diagnosis. Randomly selected, 100 cells in each Papanicolaou-stained ABC smear samples of 39 benign and malignant thyroid tumor cases were studied. Gray-level image data provided seven parameters for nuclear size, four parameters for nuclear shape, and 16 parameters showing the nuclear chromatin patterns from high-dimensional texture analysis of using co-occurrence and run-length matrices. To statistically abstract nuclear morphology, factor analysis was used. Factor analysis classified morphological nuclear characters as abstraction parameter into five abstract parameters composed of nuclear size, shape, heterogeneity, and contrast and homogeneity of chromatin pattern. The nuclei of papillary carcinoma showed larger size, more irregular shape, and higher contrast of chromatin pattern than those of the benign group. The follicular carcinomas have larger nucleus in each cell and more monotonous chromatin pattern among cells in each case than those of the benign group. Morphological abstraction by morphometry with factor analysis may provide a practical approach to the detection of the underlying characteristics of nuclear morphology in aspiration biopsy cytology.

Cell Nucleus↗
PubMed2003

Spatial distribution analysis of AT- and GC-rich regions in nuclei using corrected fluorescence resonance energy transfer.

We employed microscopic intensity-based fluorescence resonance energy transfer (FRET) images with correction by donor and acceptor concentrations to obtain unbiased maps of spatial distribution of the AT- and GC-rich DNA regions in nuclei. FRET images of 137 bovine aortic endothelial cells stained by the AT-specific donor Hoechst 33258 and the GC-specific acceptor 7-aminoactinomycin D were acquired and corrected for the donor and acceptor concentrations by the Gordon's method based on the three fluorescence filter sets. The corrected FRET images were quantitatively analyzed by texture analysis to correlate the spatial distribution of the AT- and GC-rich DNA regions with different phases of the cell cycle. Both visual observation and quantitative texture analysis revealed an increased number and size of the low FRET efficiency centers for cells in the G(2)/M-phases, compared to the G(1)-phase cells. We have detected cell cycle-dependent changes of the spatial organization and separation of the AT- and GC-rich DNA regions. Using the corrected FRET (cFRET) technique, we were able to detect early DNA separation stages in late interphase nuclei.

AT Rich Sequence↗
PubMed2002

Detection of underlying characteristics of nuclear chromatin patterns of thyroid tumor cells using texture and factor analyses.

BACKGROUND: Aspiration biopsy cytology of thyroid tumors has been used more frequently in recent times to differentiate between malignant and benign lesions. Chromatin patterns of the tumor cell nuclei are one of most important factors for cytologic diagnosis. The interpretation of nuclear chromatin patterns is subjective and more difficult than that of nuclear size or shape. In the present report, we investigated how to detect underlying chromatin characteristics of benign and malignant thyroid tumor cells by means of texture and factor analyses. METHODS: We employed a computer-aided system in which light microscopy was combined with an image processor and monochrome camera. Using this system, 100 randomly selected cells in a Papanicolaou stained, aspiration biopsy cytologic smear in each case of 39 benign and malignant thyroid tumor cases were digitized. We applied two-dimensional and higher texture analyses with the use of co-occurrence and run-length matrices to analyze the chromatin patterns. Factor analysis was used to determine whether a large number of independent variables actually measured one or more underlying common variables. RESULTS: According to parameters with high factor-loading values, the morphologic chromatin characters were classified into three categories according to heterogeneity, contrast, and homogeneity of chromatin patterns. On the basis of analyses with these morphologic categories, nuclei of papillary carcinoma showed higher contrast of chromatin patterns than did those of the benign group. Moreover, there was a variety of contrasting chromatin patterns among cells in each papillary carcinoma case in comparison with the benign group. In contrast, follicular carcinomas showed a significant difference in the standard deviation of factor 3, which indicated more monotonous chromatin patterns among cells in each follicular carcinoma case than in each benign case. CONCLUSION: We believe that this technique, using texture and factor analyses, is useful in the detection of underlying characteristics of nuclear chromatin patterns in aspiration biopsy cytology.

Adenocarcinoma, Follicular↗
PubMedDate not supplied

Application of microscopic Forster resonance energy transfer to cytological diagnosis of the thyroid tumors.

We propose a novel application of microscopic Forster resonance energy transfer (FRET) to clinical cytological diagnosis based on sensitive measurements of distance changes between fluorescently labeled deoxyribose nucleic acid (DNA) molecules. We have employed the microscopic FRET imaging for investigation of six papillary carcinomas and eight benign cases. In each case the FRET images of 20 cells stained by the AT-specific donor Hoechst 33258 and the GC-specific acceptor 7-aminoactinomycin D were acquired and analyzed by texture analysis. We have not found significant difference of the mean FRET efficiency between the benign and malignant groups. On the other hand, the texture analysis revealed a significant difference of the intranuclear spatial distribution of FRET efficiencies between the benign and malignant groups. The results indicate that despite the similar average distance between the AT- and the GC-rich DNA segments in the papillary carcinomas and the benign cases, the former has more heterogeneous distribution of the AT- and the GC-rich DNA segments in nuclei compared to the benign groups. We have demonstrated that the FRET imaging is a helpful tool for the medical cytological diagnosis of human tumors by giving information on the chromatin topology on the scale below the resolution of conventional optical microscopes. (c) 2005 Society of Photo-Optical Instrumentation Engineers.

Artificial Intelligence↗