Project description:Hormones and growth factors accelerate cell proliferation of breast cancer cells, and these molecules are well investigated targets for drug development and application. The mechanisms of cell proliferation of breast cancers lacking estrogen receptor (ER) and HER2 have not been fully understood. The purpose of the present study is to find genes that are differentially expressed in breast cancers and that might significantly contribute to cell proliferation in these cancers. Forty tumor samples, consisting of ten each of immunohistochemically ER(+)/HER2(-), ER(+)/HER2(+), ER(-)/HER2(+), and ER(-)/HER2(-) cancer were analyzed using oligonucleotide microarrays. Both genes and tumor samples were subjected to hierarchical clustering. ER(+)/HER2(-) breast cancers and ER(-)/HER2(-) cancers tended to form a tumor cluster, but HER2 positive breast cancers were split into different tumor clusters. Significant differential expression between IHC-ER(-)/HER2(-) and other tumors was defined as having an expression level at least 2-fold higher or 2-fold lower, and analyzed by multi-step two-way ANOVA. Genes overexpressed differently in IHC-ER(-)/HER2(-) breast cancers compared to other all three types were 8 genes (FABP7, GABRP, GAL, CXCL13, CDC42EP4, C2F, FOXM1, CSDA), and underexpressed genes were nine including ITGB5, KIAA0310, MAGED2, PRSS11, SORL1, TGFB3, KRT18, CPE, BCAS1. No gene was directly related to cell proliferation such as cyclins, cyclin-dependent kinase, p53, p16, and the pRb and p21 families. We had a particular focus on a transcriptional factor E2F-5 from a list of genes overexpressed in ER negative breast cancers compared to ER positive breast cancers, and further examined. Gene amplification of E2F-5 was detected in 5/57 (8.8%) in breast cancers by FISH. No point mutation was found at the binding domain with DNA or dimerization partner of E2F-5. Immunohistochemically E2F-5 positive cancers were more frequent in ER(-)/HER2(-) cancer (14/27, 51.9%) than in other types of cancer (5/30, 16.7%) (p=0.05). E2F-5 positive cancers had higher Ki-67 labeling index (59.5%) than E2F-5 negative cancers (36.3%). E2F-5 positive cancers showed higher histological grade including metaplastic carcinoma, and worse clinical outcome with shorter disease free survival in node negative patients. In conclusion, we demonstrated that there is a population of breast cancer with overexpression of a cell cycle related transcriptional factor E2F-5. E2F-5 positive breast cancers were frequent in ER(-)/HER2(-) group with high Ki-67 labeling index, high histological grade and worse clinical outcome. Keywords: immunohistochemical phenotype
Project description:The Formalin-Fixed Paraffin-Embedded (FFPE) samples on selected breast cancer subtypes (ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2-) and their paired fresh fine needle aspirated biopsies (FNA) were investigated. The cases represented different subtypes of breast cancers based on their clinical receptors ER (E) and Her2 (H) status to demonstrate the ability of gene profiles to differentiate these tumors. Compared to FNA specimens, FFPE samples yielded relatively more degraded RNA, and 80% of the samples deemed suitable for cDNA-mediated annealing, selection, extension and ligation (DASL) assay. It is able to demonstrate that gene profiles from FFPE microarrays were reproducible and correlated well with the corresponding gene profiles from FNA microarrays. The gene profiles from both FNA and FFPE could differentiate the four breast cancer subtypes, and the expression levels of corresponding gene set were consistent with qRT-PCR and correlated to the clinical outcomes on published microarray data. It supports the use of FFPE specimens to develop a prognostic tool for breast cancers which can obviate the need for fresh specimens. 25 FNA specimens were processed for direct hybridization assays using Illumina Human-Ref8 version 3 BeadChips. Invasive ductal carcinoma (IDC)-type subtypes ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2- (ER: estrogen receptor, HER2: human epidermal growth factor receptor 2) were analyzed.
Project description:The Formalin-Fixed Paraffin-Embedded (FFPE) samples on selected breast cancer subtypes (ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2-) and their paired fresh fine needle aspirated biopsies (FNA) were investigated. The cases represented different subtypes of breast cancers based on their clinical receptors ER (E) and Her2 (H) status to demonstrate the ability of gene profiles to differentiate these tumors. Compared to FNA specimens, FFPE samples yielded relatively more degraded RNA, and 80% of the samples deemed suitable for cDNA-mediated annealing, selection, extension and ligation (DASL) assay. It is able to demonstrate that gene profiles from FFPE microarrays were reproducible and correlated well with the corresponding gene profiles from FNA microarrays. The gene profiles from both FNA and FFPE could differentiate the four breast cancer subtypes, and the expression levels of corresponding gene set were consistent with qRT-PCR and correlated to the clinical outcomes on published microarray data. It supports the use of FFPE specimens to develop a prognostic tool for breast cancers which can obviate the need for fresh specimens. 25 FFPE specimens were processed for whole genome DASL assays using Illumina Human-Ref8 version 3 BeadChips. Invasive ductal carcinoma (IDC)-type subtypes ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2- (ER: estrogen receptor, HER2: human epidermal growth factor receptor 2) were analyzed.
Project description:We compared the gene methylation profile of 26 breast cancer cell lines to identify variations associated with different phenotypes and molecular subtype. The panel includes 13 estrogen receptor negative (ER-) and 13 ER+ cell lines. Four of the ER- cell lines and 5 of the ER+ cell lines are HER2 positive.
Project description:We compared the gene expression profile of 26 breast cancer cell lines to identify variations associated with different phenotypes and molecular subtype. The panel includes 13 estrogen receptor negative (ER-) and 13 ER+ cell lines. Four of the ER- cell lines and 5 of the ER+ cell lines are HER2 positive.
Project description:We compared the gene methylation profile of 26 breast cancer cell lines to identify variations associated with different phenotypes and molecular subtype. The panel includes 13 estrogen receptor negative (ER-) and 13 ER+ cell lines. Four of the ER- cell lines and 5 of the ER+ cell lines are HER2 positive. Bisulphite converted DNA from the 26 samples was hybridised to the Illumina Infinium Human Methylation450 Beadchip.
Project description:The Formalin-Fixed Paraffin-Embedded (FFPE) samples on selected breast cancer subtypes (ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2-) and their paired fresh fine needle aspirated biopsies (FNA) were investigated. The cases represented different subtypes of breast cancers based on their clinical receptors ER (E) and Her2 (H) status to demonstrate the ability of gene profiles to differentiate these tumors. Compared to FNA specimens, FFPE samples yielded relatively more degraded RNA, and 80% of the samples deemed suitable for cDNA-mediated annealing, selection, extension and ligation (DASL) assay. It is able to demonstrate that gene profiles from FFPE microarrays were reproducible and correlated well with the corresponding gene profiles from FNA microarrays. The gene profiles from both FNA and FFPE could differentiate the four breast cancer subtypes, and the expression levels of corresponding gene set were consistent with qRT-PCR and correlated to the clinical outcomes on published microarray data. It supports the use of FFPE specimens to develop a prognostic tool for breast cancers which can obviate the need for fresh specimens.
Project description:The Formalin-Fixed Paraffin-Embedded (FFPE) samples on selected breast cancer subtypes (ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2-) and their paired fresh fine needle aspirated biopsies (FNA) were investigated. The cases represented different subtypes of breast cancers based on their clinical receptors ER (E) and Her2 (H) status to demonstrate the ability of gene profiles to differentiate these tumors. Compared to FNA specimens, FFPE samples yielded relatively more degraded RNA, and 80% of the samples deemed suitable for cDNA-mediated annealing, selection, extension and ligation (DASL) assay. It is able to demonstrate that gene profiles from FFPE microarrays were reproducible and correlated well with the corresponding gene profiles from FNA microarrays. The gene profiles from both FNA and FFPE could differentiate the four breast cancer subtypes, and the expression levels of corresponding gene set were consistent with qRT-PCR and correlated to the clinical outcomes on published microarray data. It supports the use of FFPE specimens to develop a prognostic tool for breast cancers which can obviate the need for fresh specimens.
Project description:Expression profiling studies have classified breast carcinomas into luminal, normal breast-like, HER2 expressing and basal-like groups, with the latter two associated with poor outcomes. This study's objectives were to define an immunohistochemical profile that identifies basal-like tumors, to identify the presence of potential drug targets, and to determine the prognostic significance of the basal-like immunophenotype in a large series with long-term follow-up. On a panel of 21 breast tumors with basal-like expression profiles, we determined that this subtype was immunohistochemically negative for estrogen receptor and HER2, but positive for basal cytokeratins, HER1 and/or c-KIT. Using breast carcinoma tissue microarrays representing 930 patients with 17.4 years mean follow-up, basal cytokeratin expression was associated with decreased disease-specific survival. HER1 expression was observed in 54% of cases positive for basal cytokeratins (vs. 11% of negative cases) and was associated with poor survival independent of nodal status and size. c-KIT expression was more common in basal-like tumors than in other breast cancers, but did not influence prognosis. A panel of four antibodies (ER, HER1, HER2, and cytokeratin 5/6) can accurately identify basal-like tumors and suggests candidate drugs for therapies targeting HER1 or c-KIT.