title: Immunohistochemical and biochemical characterization of mucin in pseudomyxoma peritonei: a case study.
abstract: We previously reported the presence of MUC2, MUC5AC and, for the first time, MUC5B in a 58-year-old male with pseudomyxoma peritonei (PMP). This is a report on the biochemical and immunohistochemical characterization of mucin in a 50-year-old female with the same rare illness. A right oophorectomy and appendicectomy and a resection of the involved omentum were performed. Approximately a litre of crude material in the sol and gel phases was obtained from the patient during laparotomy. This was briefly homogenized in 6 M guanidinium hydrochloride and proteolytic inhibitors and purified by density gradient centrifugation in caesium chloride. At laparotomy it was noted that the patient had appendiceal and ovarian masses as well as extensive mucinous deposits in the omentum and peritoneum. A mucinous adenocarcinoma of the appendix and ovary was confirmed on histology. The cells expressed both sulphated and non-sulphated acidic mucins. The presence of MUC2, MUC5AC, MUC5B and a-1-acid glycoprotein was shown by Western blotting and MUC4 by immunohistochemical staining. MUC1 and MUC6 were not detectable in the tissue. The study confirms that MUC2, MUC5AC and MUC5B are produced in the mucus of patients with PMP. The expression of MUC4 in this disease has not been previously reported.
authors.affiliation: Department of Surgery, University of Cape Town, Observatory, South Africa.
authors.forename: Anwar S
authors.initials: AS
authors.lastname: Mall
authors.forename: Zoe
authors.initials: Z
authors.lastname: Lotz
authors.forename: Marilyn
authors.initials: M
authors.lastname: Tyler
authors.forename: Paul
authors.initials: P
authors.lastname: Goldberg
authors.forename: Jeronimo
authors.initials: J
authors.lastname: Rodrigues
authors.forename: Delawir
authors.initials: D
authors.lastname: Kahn
authors.forename: Nthato
authors.initials: N
authors.lastname: Chirwa
authors.forename: Dhirendra
authors.initials: D
authors.lastname: Govender