Expression of a breast-cancer-associated protein (pS2) in human neuro-endocrine tumours

Abstract

pS2 protein expression has been demonstrated in a range of malignant tissues in an oestrogen-independent pathway. Recently, it has been demonstrated that pS2, in prostate cancer, is closely associated with neuro-endocrine differentiation. In the present study, we have analyzed, by immunohistochemistry along with microwave antigen retrieval, the expression of pS2 protein in a retrospective series of 236 human primary neuro-endocrine tumours and attempted to correlate this with the clinicopathologic features of patients and the presence of oestrogen receptor (ER). pS2 immunoreactivity was detected in 42% of small-cell lung carcinomas, 36% of lung carcinoids, 33% of phaeochromocytomas, 38% of carotidbody tumours, 31% of pancreatic neuro-endocrine tumours, 60% of stomach carcinoids, 55% of ileal carcinoids, 23% of appendiceal carcinoids and 86% of rectal carcinoids respectively in more than 10% tumour cells. No pituitary tumours displayed pS2 immunoreactivity. pS2 transcript was also detected in lung carcinoid and carotid-body tumours by Northern-blot analysis. There was a statistically higher incidence of pS2 expression in carcinoid tumours of the ileum and rectum than in those of the appendix. No association was observed between pS2 expression and the occurrence of the carcinoid syndrome; nor was any correlation observed between the occurrence of pS2 immunoreactivity and that of ER. Our results suggest that the expression of the pS2 protein in a wide spectrum of neuro-endocrine tumours may be implicated in the pathogenesis and progression of some neuro-endocrine tumours in an oestrogen-independent pathway. Int.

Expression of pS2 in prostate cancer correlates with grade and Chromogranin A expression but not with stage

“…Maisakowski et al first described the pS2 gene in the MCF-7 human breast cancer cell line [6]. The pS2 is a cysteine rich secretory protein, containing 84 amino acids and a molecular weight of 6.45 k-Da.…”

TFF1 gene expression in human medullary thyroid carcinoma

“…However, Bonkhoff et al 16 showed that TFF1, in prostate cancer, is closely associated with premalignant changes and neuroendocrine differentiation and we have recently showed TFF1 expression in some neuroendocrine tumours. 17 In the present study, we report the expression of the TFF1 protein in human sporadic and familial MTCs.…”

“…17 Briefly, 4 m paraffin sections were dewaxed and subjected to microwave antigen retrieval by immersion in citrate buffer, pH 6·0. Endogenous peroxidase was blocked with 3 per cent hydrogen peroxide for 15 min and sections were treated with 20 per cent normal rabbit serum for 20 min.…”

“…The immunohistochemical results were assessed semiquantitatively as previously described. 17 In addition, some of the more frequently expressed peptides and the general neuroendocrine markers were also immunostained as previously described; 20 this included calcitonin (CT), neurone-specific enolase (NSE), chromogranin A (CGA), pancreastatin (PST, a fragment of CGA), and protein gene product 9.5 (PGP9.5).…”

Fas Receptor Up‐Regulation and Membrane Localization Concurrent with Apoptosis in Idiopathic Esophageal Ulceration: Toward a Better Understanding of Esophageal Injury in AIDS

“…Slides were deparaffinized as described above. Antigen retrieval was done by the microwave antigen retrieval method [8]. Blocking was done by incubating 200 mL of 10% sheep serum in PBS at 37ЊC (1 h) followed by 2 washes in PBS.…”