Immunohistochemical Analysis of Neuroendocrine (NE) Differentiation in Testicular Germ Cell Tumors (GCTs): Use of Confocal Laser Scanning Microscopy (CLSM) to Demonstrate Direct NE Differentiation from GCTs

Neuroendocrine (NE) differentiation is infrequent in testicular tumors and its histogenesis is not well understood. The present study is aimed at elucidating the pathway of neuroendocrine differentiation in germ cell tumors (GCTs) of the testis. In the analysis of 46 germ cell tumor components from 23 testicular tumors, we focused on GCTs with neuroendocrine differentiation, 7 teratoma, 1 embryonal carcinoma and 1 neuroendocrine carcinoma by immunohistochemical study and confocal laser scanning microscopy (CLSM) analysis. NE marker positive cells were noted in the tumor with collision of teratoma and embryonal carcinoma (E&T tumor), in the immature columnar cells of transitional form of embryonal carcinoma to teratoma (E-T cells) and neuroendocrine carcinoma cells, in addition to the well known mature intestinal mucosa in teratoma. Double staining for a NE marker (CGA) and a germ cell marker (PLAP) demonstrated the localization of both proteins in the same E-T cells confirmed by CLSM. Another finding, indicating the intimate relation between embryonal carcinoma and neuroendcrine differentiation, is that neuroendocrine carcinoma expressed a marker of embryonal carcinoma, CD30. The present results indicated that the NE cells might be differentiated from embryonal carcinoma, a view that has not been proposed before, but that is made in the present study using CLSM

Structural mechanism and photoprotective function of water-soluble chlorophyll-binding protein

This research was originally published in Journal of Biological Chemistry. Daisuke Horigome, Hiroyuki Satoh, Nobue Itoh, Katsuyoshi Mitsunaga, Isao Oonishi, Atsushi Nakagawa and Akira Uchida. Structural mechanism and photoprotective function of water-soluble chlorophyll-binding protein. Journal of Biological Chemistry. 2007; 282, 6525-6531. © the American Society for Biochemistry and Molecular Biology