Intramucosal fat is uncommon in large bowel polyps but raises three differential diagnoses.

Aims: This case series intends to expand currently limited knowledge regarding the existence and diagnostic significance of intramucosal fat in colorectal polyps.

Methods: Clinicopathological features of nine such polyps were reported following histopathological review, including S100 and EMA immunohistochemistry.

Results And Conclusions: Such review subdivided seven polyps into three groups: (1) mucosal perineurioma/serrated polyps with fat among the perineurial stroma (three cases); (2) submucosal lipomas with adipose tissue extending into the overlying mucosa (two cases) and (3) polyps with intramucosal adipose tissue only, that is, the newly described but less-recognised entity known as intramucosal lipoma (two cases).

Specific histological abnormalities are more likely in biopsies of endoscopically normal large bowel after the age of 60 years.

Aims: Colonic and rectal biopsies, often taken from an endoscopically normal large bowel, form a significant proportion of the histopathology workload. The aim of this study was to determine diagnostic yield from mucosal biopsies in patients with normal colonoscopy or sigmoidoscopy, and whether or not diarrhoea is predictive of abnormal histology.

Methods And Results: A retrospective analysis of pathology requests, endoscopy and pathology reports taken during 1 year was undertaken in a tertiary care hospital for all biopsies from endoscopically normal ileal, colonic and rectal mucosa.

Treatment-dependent androgen receptor mutations in prostate cancer exploit multiple mechanisms to evade therapy.

Mutations in the androgen receptor (AR) that enable activation by antiandrogens occur in hormone-refractory prostate cancer, suggesting that mutant ARs are selected by treatment. To validate this hypothesis, we compared AR variants in metastases obtained by rapid autopsy of patients treated with flutamide or bicalutamide, or by excision of lymph node metastases from hormone-naïve patients. AR mutations occurred at low levels in all specimens, reflecting genetic heterogeneity of prostate cancer.

Profiling human androgen receptor mutations reveals treatment effects in a mouse model of prostate cancer.

Gain-of-function mutations in the androgen receptor (AR) are found in prostate cancer and are implicated in the failure of hormone therapy. Most studies have emphasized the ligand-binding domain (LBD) where mutations can create promiscuous receptors, but mutations in the NH(2)-terminal transactivation domain have also been found. To assess AR alteration as a mechanism of treatment resistance, a mouse model (h/mAR-TRAMP) was used in which the murine AR coding region is replaced by human sequence and prostate cancer initiated by a transgenic oncogene.

Androgen receptor variants and prostate cancer in humanized AR mice.

Androgen, acting via the androgen receptor (AR), is central to male development, differentiation and hormone-dependent diseases such as prostate cancer. AR is actively involved in the initiation of prostate cancer, the transition to androgen independence, and many mechanisms of resistance to therapy. To examine genetic variation of AR in cancer, we created mice by germ-line gene targeting in which human AR sequence replaces that of the mouse.

Glutamine tract length of human androgen receptors affects hormone-dependent and -independent prostate cancer in mice.

The androgen receptor (AR) is involved in the initiation and progression of prostate cancer and its transition to androgen independence. Genetic variation in AR may contribute to disease risk and has been studied for a polymorphic N-terminal glutamine (Q) tract that shows population heterogeneity. While the length of this tract is known to affect AR in vitro, association with disease is complicated by genetic and environmental factors that have led to discordant epidemiological findings.

Synthesis and secretion of angiotensin II by the prostate gland in vitro.

The renin angiotensin system has been shown to have tissue-related functions that are distinct from its systemic roles. We showed that angiotensin II type 1 (AT1) receptors are present in mammalian sperm, and angiotensin II stimulates sperm motility and capacitation. In addition, angiotensin II is present in human seminal plasma at concentrations higher than found in blood.