title: Elevated oestrogen receptor splice variant ERαΔ5 expression in tumour-adjacent hormone-responsive tissue.
abstract: Susceptibility to prostate or endometrial cancer is linked with obesity, a state of oestrogen excess. Oestrogen receptor (ER) splice variants may be responsible for the tissue-level of ER activity. Such micro-environmental regulation may modulate cancer initiation and/or progression mechanisms. Real-time reverse transcriptase (RT) polymerase chain reaction (PCR) was used to quantitatively assess the levels of four ER splice variants (ERαΔ3, ERαΔ5, ERβ2 and ERβ5), plus the full-length parent isoforms ERα and ERβ1, in high-risk [tumour-adjacent prostate (n = 10) or endometrial cancer (n = 9)] vs. low-risk [benign prostate (n = 12) or endometrium (n = 9)], as well as a comparison of UK (n = 12) vs. Indian (n = 15) benign prostate. All three tissue groups expressed the ER splice variants at similar levels, apart from ERαΔ5. This splice variant was markedly raised in all of the tumour-adjacent prostate samples compared to benign tissues. Immunofluorescence analysis for ERβ2 in prostate tissue demonstrated that such splice variants are present in comparable, if not greater, amounts as the parent full-length isoform. This small pilot study demonstrates the ubiquitous nature of ER splice variants in these tissue sites and suggests that ERαΔ5 may be involved in progression of prostate adenocarcinoma.
authors.affiliation: Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster LA1 4YQ, UK. siantaylor@gmail.com
authors.forename: Siân E
authors.initials: SE
authors.lastname: Taylor
authors.forename: Imran I
authors.initials: II
authors.lastname: Patel
authors.forename: Paras B
authors.initials: PB
authors.lastname: Singh
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Nicholson
authors.forename: Helen F
authors.initials: HF
authors.lastname: Stringfellow
authors.forename: R K
authors.initials: RK
authors.lastname: Gopala Krishna
authors.forename: Shyam S
authors.initials: SS
authors.lastname: Matanhelia
authors.forename: Pierre L
authors.initials: PL
authors.lastname: Martin-Hirsch
authors.forename: Francis L
authors.initials: FL
authors.lastname: Martin
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D018076:DNA, Complementary; D016889:Endometrial Neoplasms / Q000235:genetics*; D004717:Endometrium / Q000378:metabolism*; D047628:Estrogen Receptor alpha / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008856:Microscopy, Fluorescence; D009376:Neoplasms, Hormone-Dependent / Q000235:genetics*; D011467:Prostate / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000235:genetics*; D012326:RNA Splicing; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D047628:Estrogen Receptor alpha