Normal Reproductive Function in InhBP/p120-Deficient Mice

The inhibins are gonadal transforming growth factor β superfamily protein hormones that suppress pituitary follicle-stimulating hormone (FSH) synthesis. Recently, betaglycan and inhibin binding protein (InhBP/p120, also known as the product of immunoglobulin superfamily gene 1 [IGSF1]) were identified as candidate inhibin coreceptors, shedding light on the molecular basis of how inhibins may affect target cells. Activins, which are structurally related to the inhibins, act within the pituitary to stimulate FSH production. Betaglycan increases the affinity of inhibins for the activin type IIA (ACVR2) receptor, thereby blocking activin binding and signaling through this receptor. InhBP/p120 may not directly bind inhibins but may interact with the activin type IB receptor, ALK4, and participate in inhibin B's antagonism of activin signaling. To better understand the in vivo functions of InhBP/p120, we characterized the InhBP/p120 mRNAs and gene in mice and generated InhBP/p120 mutant mice by gene targeting in embryonic stem cells. InhBP/p120 mutant male and female mice were viable and fertile. Moreover, they showed no alterations in FSH synthesis or secretion or in ovarian or testicular function. These data contribute to a growing body of evidence indicating that InhBP/p120 does not play an essential role in inhibin biology

Metastatic Prostatic Carcinoma to Testis: Histological Features Mimicking Lymphoma

We report a case of prostatic carcinoma with testicular metastasis, which mimicked malignant lymphoma of the testis. The patient was a 71 year-old man with a history of prostate adenocarcinoma of Gleason score 9 (4+5) diagnosed in 2001 for which he received hormonal therapy. Four years later, the patient developed multiple osteoblastic bone metastases. Radiotherapy of the bone metastases was given with subsequently bilateral orchiectomy for hormonal deprivation therapy in May 2005. Grossly, one of the testes had a subcapsular rubbery 0.9 cm nodule. Microscopically, the nodule was composed of malignant discohesive cells predominantly infiltrating in the interstitium with an appearance of malignant lymphoma. However, immunohistochemical stains were positive for prostate-specific antigen and prostate acid phosphatase and negative for leukocyte common antigen, which confirmed the diagnosis of metastatic prostate adenocarcinoma