Distribution and significance of caveolin 2 expression in normal breast and invasive breast cancer: an immunofluorescence and immunohistochemical analysis

Abstract

Our results demonstrate that CAV2 is preferentially expressed in basal-like cancers and is associated with poor prognosis. Further in vitro studies are required to determine whether CAV2 has oncogenic properties or is only a surrogate marker of basal-like carcinomas.

Caveolin 1 and Caveolin 2 are associated with breast cancer basal-like and triple-negative immunophenotype

“…Furthermore Savage et al, have recently reported high prevalence of CAV1 and CAV2 expression in basal-like breast carcinomas (Savage et al, , 2008, and observed CAV1 gene amplification in a small subgroup of basal-like breast cancers (Savage et al, , 2008. Moreover, these findings support Pinilla et al who described an association between CAV1 expression and sporadic basal-like breast cancers and familial BRCA1 tumours (Pinilla et al, 2006).…”

“…Despite the controversy about the distribution of CAV1 and CAV2 in normal and invasive breast cancer (Yang et al, 1998;Hurlstone et al, 1999;Chen et al, 2004;Sagara et al, 2004;Park et al, 2005; Van den Eynden et al, 2006), recent studies confirmed the preferential expression of both genes and their proteins in normal myoepithelial cells (Pinilla et al, 2006;Savage et al, 2007Savage et al, , 2008. Furthermore Savage et al, have recently reported high prevalence of CAV1 and CAV2 expression in basal-like breast carcinomas (Savage et al, , 2008, and observed CAV1 gene amplification in a small subgroup of basal-like breast cancers (Savage et al, , 2008.…”

“…Caveolin-1 was first thought to have tumour suppressor properties (Razani et al, 2001a, b;Hnasko and Lisanti, 2003), based on the finding of an arguable inactivating point mutation in CAV1, the silencing of CAV1 gene expression by promoter hypermethylation in breast cell lines and prostate tumour samples (Engelman et al, 1999;Hurlstone et al, 1999;Cui et al, 2001) and the apparent downregulation of CAV1 in breast cancer (Chen et al, 2004;Park et al, 2005). In recent years, there has been increasingly more coherent data to suggest that CAV1 and CAV2 may also have oncogenic properties in breast (Hurlstone et al, 1999;Pinilla et al, 2006; Van den Eynden et al, 2006;Savage et al, 2007Savage et al, , 2008, prostate (Yang et al, 1998;Thompson et al, 1999), bladder (Rajjayabun et al, 2001;Fong et al, 2003), oesophageal (Kato et al, 2002;Ando et al, 2007), thyroid, pancreatic, non-small cell and squamous lung cancer (Kato et al, 2004;Sunaga et al, 2004).…”

Basal-like and triple-negative breast cancers: a critical review with an emphasis on the implications for pathologists and oncologists

“…5 More recently, a subgroup of lobular carcinomas has been shown to express high-molecular-weight cytokeratins, 41 however it remains to be determined whether these cases truly show a basal-like transcriptome. The majority of basal-like breast cancers lack or show low levels of ER and PR, lack HER2 protein overexpression and HER2 gene amplification, whereas they express genes and proteins usually found in 'basal'/myoepithelial cells of the normal breast including high-molecular-weight cytokeratins (5/6, 14 and 17), 17,19,21,42 P-cadherin, 43 caveolins 1 and 2, 44,45 nestin, 46 aB crystallin, 47,48 CD109, 49,50 and EGFR 17 and, in a minority of cases, harbor EGFR gene amplification 51 or aneusomy. 52 p53 immunohistochemical expression or TP53 gene mutations is observed in up to 85% of cases, 53,54 and alterations of the pRB and p16 G1/S cell-cycle checkpoint are remarkably prevalent in these cancers.…”

A high-resolution integrated analysis of genetic and expression profiles of breast cancer cell lines

“…The expression profile of luminal cells is dominated by ESR1 (ERa) expression and that of a large number of genes that are associated with oestrogen response in breast cancer including FOXA1, TFF1, AGR2 and GATA3 [19]. Basal specific genes in breast cancer cell lines included two isoforms of caveolin (CAV1 and CAV2), as well as VIM, LY6K and PRNP as previously described [28][29][30]. These genes correlate well with our previous reports of oestrogen responsive genes in primary breast cancers [19] and with genes associated with the basal-like phenotype of breast epithelial cells [26] and primary basal-like breast cancers [3].…”