Takada S

Aggressive angiomyxoma in the scrotum expressing androgen and progesterone receptors

Abstract  Aggressive angiomyxoma is a rare benign mesenchymal myxoid tumor that arises from the pelvic soft tissues and perineum in relatively young females. This tumor has the ability to infiltrate locally and has a high risk of local recurrence after extirpation, but no potential to metastasize. We report here a rare case of aggressive angiomyxoma that developed in the scrotum of a 47‐year‐old male. Immunostaining of the resected specimen revealed that the tumor cell nuclei stained strongly and diffusely for androgen receptors (80% of the tumor cells), and moderately and partly for progesterone receptors (20% of the tumor cells). However, staining was negative for estrogen receptors. It is highly suggested that the growth of aggressive angiomyxoma in males may depend on androgen manipulation, contrary to its frequent and close association with estrogen receptor expression, which has been reported in females.

Delivery of PTEN via a novel gene microcapsule sensitizes prostate cancer cells to irradiation

The tumor suppressor gene MMAC/PTEN located on chromosome10q23.3 has dual phosphatase activity in the phosphoinositide-3-kinase signaling pathway and inhibits Akt activation, a serine-threonine kinase, which is involved in proliferative and antiapoptotic pathways. Furthermore, MMAC/PTEN is frequently inactivated in a variety of tumors including prostate cancer. In this study, we generated a new type of gene transfer drug, GelaTen, which is a microsphere of cationized gelatin hydrogels incorporating PTEN plasmid DNA. Using our previously reported radiation-resistant PC3-Bcl-2 human prostate cancer cells (PTEN deleted), we examined the efficacy of GelaTen to force the expression of PTEN in vivo to inhibit tumor growth after intratumoral injection alone or with irradiation. Combinational therapy with GelaTen and irradiation improved both the in vitro and in vivo efficacy of growth inhibition compared with GelaTen or irradiation alone. These data show that GelaTen gene therapy, enabling radiosensitization, can potentially treat prostate cancers that have MMAC/PTEN gene alterations associated with radioresistance. [Mol Cancer Ther 2008;7(7):1864–70]