Searchable abstracts of presentations at key conferences in endocrinology

ea0004oc16 | Endocrine tumours and neoplasia | SFE2002

IGF-I prevents deoxycholic acid-induced apoptosis in HT29 colorectal cells

Khalaf S , Ogunkolade W , Davies D , Bustin S , Jenkins P

Background: The pro-proliferative and anti-apoptotic IGF-I is implicated in the development of colorectal cancer (CRC) in both the general population and patients with acromegaly. The local intracolonic environment is also likely to be important, particularly unconjugated bile acids such as deoxycholic acid (DCA). Whilst low faecal concentrations may be proliferative, high levels are toxic to colonic epithelial cells.High levels of DCA have been linked t...

ea0004p35 | Cytokines and growth factors | SFE2002

Paracrine IGF-I expression in the colon is associated with elevations of tumourigenic genes

Kelly P , Ogunkolade B , Fairclough P , Bustin S , Jenkins P

Introduction: The GH/IGF-I axis is implicated in colorectal cancer development. We have previously shown regional variations of the GH/IGF-I axis, and other tumour associated genes between the rectum (RS) and caecum (C). Whether variations in the GH/IGF-I axis align with differing expression patterns is unknown.Aim: To determine the association between colonic expression of the GH/IGF-I axis and that of tumour associated genes by region.<p class="abs...

ea0004p64 | Endocrine tumours and neoplasia | SFE2002

The differential expression of 22kDa and 20kDa growth hormone isomers in normal and malignant colon and breast tissue

Mistry R , Kelly P , Ogunkolade B , Bustin S , Jenkins P

Background. The GH/IGF-I axis has been implicated in the pathogenesis of colon and breast cancer. We have recently demonstrated that the local expression of its components correlates with that of tumour-associated genes and angiogenesis. The two predominant isomers of GH in humans are 22kDa and 20kDa isomers. A recent study reported that the two isomers exert opposing effects on breast cancer cells: 22kDa GH promotes proliferation whereas 20kDa GH inhibits proliferation. The l...

ea0003p73 | Cytokines and Growth Factors | BES2002

The universal expression of ghrelin in normal and malignant breast tissue and its association with tumourigenic genes

Laban C , Ogunkolade W , Bustin S , Carpenter R , Jenkins P

Background: The growth hormone/ insulin-like growth factor-1 (GH/IGF-1) axis has been increasingly implicated in the pathogenesis of breast cancer. We have recently demonstrated the local expression of both GH and IGF-I in normal and malignant breast tissue. However, the regulation of this local GH/IGF-1 expression is unknown. Aims: (i) To quantify the mRNA levels of GHRH, ghrelin and their receptors in malignant and adjacent normal breast tissue, and (ii) to determine any cor...

ea0011oc40 | Neuroendocrinology and neoplasia | ECE2006

Expression of IGF-I & IGF-IR in tamoxifen sensitive and tamoxifen resistant breast cancer

McVittie CJ , Khalaf S , Ogunkolade W , Carpenter R , Bustin SA , Jenkins PJ

Background: The growth hormone/ IGF-I axis is important in the pathogenesis of breast cancer and increased IGF-I signalling through the IGF-I receptor (IGF-IR) has been implicated in the development of tamoxifen resistance in breast cancer.Aims: To compare mRNA and protein expression of IGF-I & IGF-IR in (i) wild type (WT) and tamoxifen resistant (TR) MCF-7 breast cancer cells and (ii) breast cancer tissue from women with primary and recurrent, tamox...

ea0011p477 | Endocrine tumours and neoplasia | ECE2006

Insulin-like growth factor-i signalling in tamoxifen sensitive and tamoxifen resistant breast cancer cells

McVittie CJ , Khalaf S , Ogunkolade W , Carpenter R , Bustin SA , Jenkins PJ

Background: Due to its cross-talk with estrogen receptor (ER) signalling, increased IGF-I signalling through the IGF-I receptor (IGF-IR) has been postulated as an important factor in the development of tamoxifen resistance in breast cancer.Aims: To investigate the importance of IGF-I signalling in tamoxifen resistant (TR) and wild-type (WT) MCF-7 breast cancer cells by (i) assessing cell proliferation in response to IGF-I and tamoxifen and (ii) using sma...

ea0011p765 | Steroids | ECE2006

NaB affect the local regulation of vitamin D in colorectal cancer

Ogunkolade BW , Khalaf S , Boucher BJ , Davis D , Dorudi S , Jenkins PJ , Bustin SA

Introduction: The development of colorectal cancer is influenced by dietary as well as growth factors. Butyrate, (NaB) one of the metabolic by-products of bacterial fermentation of dietary fibre is a primary source of energy for colonic mucosa. It has growth-promoting effects on normal colonic epithelial cells, induces cell cycle arrest, differentiation and apoptosis in colorectal cancer cells. Since it has been suggested that the apoptotic effects of NaB may be due to its syn...

ea0009p85 | Endocrine tumours and neoplasia | BES2005

Tissue specific regulation of IGF-1 expression by GH

Ogunkolade B , Khalaf S , Kelly P , Bustin S , Kelly P , Binart N , Kopchick J , Jenkins P

Introduction:Hepatic IGF-I is generally believed to be regulated by pituitary-derived GH. However recent studies have emphasized the importance of paracrine/autocrine IGF-I in normal growth and development, as well as some malignancies. However, it remains unclear how locally produced IGF-I is regulated. The aim of this project was to investigate IGF-I expression in different tissues from the growth hormone receptor knock-out (GHR-KO) mouse.<p class=...

ea0009p88 | Endocrine tumours and neoplasia | BES2005

Long term culture of MCF-7 breast cancer cells with siRNA to the IGF-I receptor causes continued transcriptional silencing of the IGF-I receptor and decreased cell proliferation

McVittie C , Ogunkolade W , Khalaf S , Macaulay V , Bustin S , Carpenter R , Jenkins P

Introduction: The GH/IGF-I axis has been implicated in the pathogenesis of breast cancer and development of tamoxifen resistance. We have previously used siRNA to successfully silence the IGF-I receptor (IGF-IR) in MCF-7 breast cancer cells. To further characterize the growth changes that occur when elements of the GH/IGF-I axis are disrupted we investigated the use of siRNA to cause long term silencing of IGF-IR.Methods: MCF-7 cells were cultured in phe...

ea0007oc24 | Endocrine tumours | BES2004

Microarray analysis of IGF-I mRNA positive and negative breast tumours

Laban C , McCarthy K , Ogunkolade B , Bustin S , Ahmed S , Carpenter R , Jenkins P

Background: There is considerable evidence to support a role for the GH/IGF-I axis in the development of breast cancer. We have previously demonstrated that IGF-I is expressed in both normal and malignant breast tissue, but that approximately 10% of primary breast cancers reveal no IGF-I mRNA expression. However the molecular differences between IGF-I positive and IGF-I negative tumours is unknown.Aims: To investigate the molecular differences between IG...