Molecular studies of ovarian cancer cell lines and tumor specimens have identified genetic mutations in some of these genes, KRAS, NRAS and BRAF, which result in the alteration of signaling through this critical pathway [2], [19] [23].
Studies on plasma specimens have identified a number of candidate biomarkers [ 32– 32].
Studies comparing the expression levels of miRNAs between OA tissue specimens and normal cartilage tissue/non-OA tissue specimens have identified several miRNAs as being involved in the pathogenesis of OA.
Unfortunately, although several gene expressions profiling studies of primary tumor specimens have identified prognostic signatures [ 5– 12], so far none of the latter has a predictive power within the subset of stage 4 patients aged > 18 months at diagnosis.
Data obtained by retrospective examination of museum specimens have identified the date of first occurrence as 1974 in the United States (8 ), 1978 in Australia (9 ), 1986 in Eduador (10 ), and 1999 in New Zealand (7 ).
Encouragingly, recent molecular and proteomic analyses of autopsy specimens have identified key genetic alterations in DIPG, including amplifications in genes encoding receptor tyrosine kinases (PDGFRA, MET) [ 2], PDGFRA mutations [ 3], as well as distinct DIPG subgroups based on Hedgehog (SHH) and MYCN pathway activation [ 4].
Immunohistochemical studies in surgical specimens have identified significant differences in the expression levels of several steroid hormone receptors and their related proteins between nonneoplastic urothelium versus urothelial tumor and between low-grade/non-muscle-invasive versus high-grade/muscle-invasive urothelial tumors.
Gene expression studies performed on human breast cancer specimens have identified a breast cancer molecular subtype 'claudin-low' population [ 68] that expresses an overlapping gene signature with that of CSC populations enriched with CD44+/CD24-/low CD44+/CD24-/loworescells-activated cell sorting (FACS), and mammospheres [ 69].
A combined investigative model, analysing the transcriptional response in clinical tumour specimens and cancers cell lines, has identified APRIL, a novel chemo-resistance biomarker with independent predictive impact in 5FU-treated CRC patients, that may represent a target for novel therapeutics.
