Aggrus (also known as T1a/podoplanin) is a membrane sialoglycoprotein whose function in tumors is unknown. We recently determined that Aggrus possessed the ability of inducing platelet aggregation and that its expression was frequently upregulated in colorectal tumors. Thus, Aggrus expression might be associated with tumorinduced platelet aggregation and tumor metastasis. Here we show, by means of cancer profiling array and real-time PCR, that aggrus mRNA expression is frequently upregulated in testicular germ cell tumors when compared with the surrounding normal tissue. Immunohistochemical staining revealed that Aggrus protein expression was detected in 10 of 11 seminomas (90.9%), but its expression was not observed in embryonal carcinomas (0/4; 0%). Specific markers for seminomas have not been reported, and Aggrus is a potential diagnostic marker for seminomas and may be associated with malignancies of the testis.

Podoplanin (Aggrus) is a mucin-type sialoglycoprotein that plays a key role in tumor cell-induced platelet aggregation. Podoplanin possesses a platelet aggregation-stimulating (PLAG) domain, and Thr52 in the PLAG domain of human podoplanin is important for its activity. Endogenous or recombinant human podoplanin were purified, and total glycosylation profiles were surveyed by lectin microarray. Analyses of glycopeptides produced by Edman degradation and mass spectrometry revealed that the disialyl-corel (NeuAca2-3Galbl-3(NeuAca2-6)GalNAcal-O-Thr) structure was primarily attached to a glycosylation site at residue Thr52. Sialic acid-deficient podoplanin recovered its activity after additional sialylation. These results indicated that the sialylated Corel at Thr52 is critical for podoplanin-induced platelet aggregation.

The association of CO with homozygosity for the specific ESR1 haplotype suggests the relevance of genetic susceptibility to EEDs in the development of CO.

Our followup study of 48 patients with primary aldosteronism concerns the results of 2 different operative methods. After preoperative localization of the unilateral solitary tumor 22 patients underwent unilateral adrenalectomy and 26 underwent enucleation of aldosterone-producing adenoma. Both operative methods improved hypertension, hypokalemia, the low urinary sodium-to-potassium ratio, suppressed plasma renin activity, high plasma aldosterone concentration, high urinary aldosterone excretion and high urinary kallikrein excretion in similar orders of magnitude for 5 years. Levels of plasma cortisol and plasma adrenocorticotropic hormone following respective operations were also identical. Five years postoperatively, ambulation and furosemide administration under low sodium diet stimuli remarkably enhanced plasma renin activity and plasma aldosterone concentration in the aldosterone-producing adenoma enucleation group (p < 0.001), almost similar to that of normal subjects but increment magnitudes were slight (p < 0.05 to < 0.01) in the adrenalectomy group. Preoperatively, angiotensin II infusion failed to increase plasma aldosterone concentration in patients with primary aldosteronism. After respective operations, responses of plasma aldosterone concentration to angiotensin II infusion and of plasma cortisol to adrenocorticotropic hormone administration in the aldosterone-producing adenoma enucleation group were more sensitive than those in the adrenalectomy group. There was no remission of recurrent hyperaldosteronism in either group throughout the study. These results suggest that angiotensin II induces aldosterone release by an activation of tumor uninvolved cortical cells and that the enucleation of aldosterone-producing adenoma is more preferable than unilateral adrenalectomy.

The results suggest that a novel gene(s) for urinary development and that for genital development reside in the approximately 20 cM region distal to D10S186 and in the approximately 10 cM region distal to D10S1248, respectively, although it remains to be determined whether the two types of genes are identical or different.