Strong EZH2 expression was associated with increased tumor cell proliferation in all four cancer types. Associations were also found between EZH2 and important clinicopathologic variables. EZH2 expression showed significant prognostic impact in melanoma, prostate, and endometrial carcinoma in univariate survival analyses, and revealed independent prognostic importance in carcinoma of the endometrium and prostate. CONCLUSION Our findings point at EZH2 as a novel and independent prognostic marker in endometrial cancer, and validate previous findings on prostate and breast cancer. Further, EZH2 expression was associated with features of aggressive cutaneous melanoma. The fact that EZH2 might identify increased tumor cell proliferation and aggressive subgroups in several cancers may be of practical interest because the polycomb group proteins have been suggested as candidates for targeted therapy. EZH2 expression should, therefore, be further examined as a possible predictive factor.

Metastasis underlies the majority of cancer-related deaths. Thus, furthering our understanding of the molecular mechanisms that enable tumor cell dissemination is a vital health issue. Epithelialto-mesenchymal transitions (EMTs) endow carcinoma cells with enhanced migratory and survival attributes that facilitate malignant progression. Characterization of EMT effectors is likely to yield new insights into metastasis and novel avenues for treatment. We show that the presence of the receptor tyrosine kinase Axl in primary breast cancers independently predicts strongly reduced overall patient survival, and that matched patient metastatic lesions show enhanced Axl expression. We demonstrate that Axl is strongly induced by EMT in immortalized mammary epithelial cells that establishes an autocrine signaling loop with its ligand, Gas6. Epiallelic RNA interference analysis in metastatic breast cancer cells delineated a distinct threshold of Axl expression for mesenchymal-like in vitro cell invasiveness and formation of tumors in foreign and tissue-engineered microenvironments in vivo. Importantly, in two different optical imagingbased experimental breast cancer models, Axl knockdown completely prevented the spread of highly metastatic breast carcinoma cells from the mammary gland to lymph nodes and several major organs and increased overall survival. These findings suggest that Axl represents a downstream effector of the tumor cell EMT that is required for breast cancer metastasis. Thus, the detection and targeted treatment of Axl-expressing tumors represents an important new therapeutic strategy for breast cancer.carcinoma | receptor tyrosine kinase | breast cancer

Previous studies have shown that BRCA1-related breast cancers are often high-grade tumors that do not express estrogen receptors, HER2, p27Kip1 , or cyclin D1, but do express p53 and cyclin E. In addition, the expression of cytokeratin 5/6 (CK5/6), indicating a basal epithelial phenotype, is frequent in BRCA1-related breast cancer. Here, in a series of 247 breast cancers, we demonstrate that CK5/6 expression was associated with nearly all of the features of BRCA1-related breast cancer and was also associated with a poor prognosis. In a parsimonious multivariable proportional hazards model, protein levels of cyclin E, p27Kip1 , p53, and the presence of glomeruloid microvascular proliferation all independently predicted outcome after breast cancer. In this model, only cyclin E and p27Kip1 levels were independent predictors in lymph node-negative cancers, whereas glomeruloid microvascular proliferation and tumor size independently predicted outcome in node-positive disease. The molecular determinants of the basal epithelial phenotype encapsulate many of the key features of breast cancers occurring in germ-line BRCA1 mutation carriers and have independent prognostic value. Basal breast cancer deserves recognition as an important subtype of breast cancer.

Although 75% of endometrial cancers are treated at an early stage, 15% to 20% of these recur. We performed an integrated analysis of genome-wide expression and copy-number data for primary endometrial carcinomas with extensive clinical and histopathological data to detect features predictive of recurrent disease. Unsupervised analysis of the expression data distinguished 2 major clusters with strikingly different phenotypes, including significant differences in disease-free survival. To identify possible mechanisms for these differences, we performed a global genomic survey of amplifications, deletions, and loss of heterozygosity, which identified 11 significantly amplified and 13 significantly deleted regions. Amplifications of 3q26.32 harboring the oncogene PIK3CA were associated with poor prognosis and segregated with the aggressive transcriptional cluster. Moreover, samples with PIK3CA amplification carried signatures associated with in vitro activation of PI3 kinase (PI3K), a signature that was shared by aggressive tumors without PIK3CA amplification. Tumors with loss of PTEN expression or PIK3CA overexpression that did not have PIK3CA amplification also shared the PI3K activation signature, high protein expression of the PI3K pathway member STMN1, and an aggressive phenotype in test and validation datasets. However, mutations of PTEN or PIK3CA were not associated with the same expression profile or aggressive phenotype. STMN1 expression had independent prognostic value. The results affirm the utility of systematic characterization of the cancer genome in clinically annotated specimens and suggest the particular importance of the PI3K pathway in patients who have aggressive endometrial cancer.amplification ͉ endometrial cancer ͉ prognosis ͉ comparative genomic hybridization ͉ stathmin expression W ith a 2% to 3% lifetime risk among women, endometrial cancer is the most common pelvic gynecologic malignancy in industrialized countries, and the incidence is increasing (1). Approximately 75% of cases are diagnosed with the tumor confined to the uterine corpus (1, 2), but after primary surgery 15% to 20% of these tumors recur and have limited response to systemic therapy. In light of these recurrences, patients who have localized endometrial cancer have 2 major needs: (1) adjuvant therapies that will reduce the recurrence rate, and (2) the ability to target these therapies to the patients in whom disease is most likely to recur. In addition, women who have metastatic disease require effective systemic therapy.The needs for effective systemic therapies and for reliable prognostic markers have been addressed only partly. The most common basis for determining risk of recurrent disease has been the categorization of endometrial cancer into 2 subtypes. The majority are type I, associated with good prognosis, low stage and grade, and endometrioid histology. In contrast, type II cancers are characterized by high stage and grade, nonendometrioid histology, and poor prognosis. The prognostic value of this distinction is ...

Oncogenic activation of tyrosine kinases is a common mechanism of carcinogenesis and, given the druggable nature of these enzymes, an attractive target for anticancer therapy. Here, we show that somatic mutations of the fibroblast growth factor receptor 2 (FGFR2) tyrosine kinase gene, FGFR2, are present in 12% of endometrial carcinomas, with additional instances found in lung squamous cell carcinoma and cervical carcinoma. These FGFR2 mutations, many of which are identical to mutations associated with congenital craniofacial developmental disorders, are constitutively activated and oncogenic when ectopically expressed in NIH 3T3 cells. Inhibition of FGFR2 kinase activity in endometrial carcinoma cell lines bearing such FGFR2 mutations inhibits transformation and survival, implicating FGFR2 as a novel therapeutic target in endometrial carcinoma.endometrial cancer ͉ fibroblast growth factor receptor 2 ͉ oncogene ͉ targeted therapy ͉ tyrosine kinase T yrosine kinases play a major role in transduction of proliferative signals and can become oncogenic when deregulated by somatic mutation (1). Somatically altered tyrosine kinases have proven to be tractable therapeutic targets in several tumor types; examples of successfully targeted tyrosine kinases include ABL1 in chronic myeloid leukemia (2), KIT in gastrointestinal stromal tumors (3), ERBB2 in breast cancer (4), and EGFR in non-small-cell lung cancer (5-7). The tyrosine kinase family has not been exhaustively studied in human cancer, and it is likely that additional tyrosine kinase therapeutic targets remain to be discovered.The fibroblast growth factor receptor (FGFR) tyrosine kinase family, which is comprised of four kinases that differentially respond to 18 FGF ligands (8, 9), has long been implicated in cancer. Translocations involving FGFR3, and activating somatic mutations in FGFR3, have been identified in multiple myeloma patients (10, 11), and translocations of FGFR1 have been found in patients with 8p11 myeloproliferative syndrome (12). Isolated cases of a missense mutation of FGFR4 in a lung adenocarcinoma patient and missense mutations of FGFR2 in a lung squamous cell carcinoma patient and gastric cancer patient have also been reported (13,14). In addition to these documented examples of somatic mutation of FGFR family members in cancer, a germ-line polymorphism in the second intron of FGFR2 was found to be associated with breast cancer in genomewide association studies (15,16).FGFR1-FGFR3 are characterized by alternative splicing of the mRNA encoding the third Ig-like repeat in the extracellular ligand-binding domain. This differential splicing determines ligand specificity such that isoforms expressed primarily in epithelial cells (IIIb) preferentially bind FGF ligands expressed by mesenchymal cells, and isoforms expressed primarily in mesenchymal cells (IIIc) preferentially bind FGF ligands expressed by epithelial cells (17)(18)(19). Alteration of this restricted expression pattern can lead to oncogenic transformation (20). Mutations in FGFR2 and FGF...

The polycomb group protein enhancer of zeste homologue 2 (EZH2) has been linked to invasive properties of aggressive breast cancer. In this report, tissue microarray analysis of 190 breast carcinomas from a nested case-control study shows that EZH2 is significantly associated with interval breast cancers. Further, a strong relationship was found with tumor cell proliferation (by Ki-67 expression), locally advanced disease, metastasis at presentation, markers of the basal epithelial phenotype (positivity for cytokeratin 5/6 or P-cadherin), and p53 status. EZH2 expression was also significantly associated with glomeruloid microvascular proliferation, an aggressive angiogenic phenotype. For prediction of aggressive disease (any event of locally advanced disease, lymph node spread, or distant spread), EZH2 was the only variable of significance in multivariate analysis, whereas no additional information was given by Ki-67. Although EZH2 expression was significant in univariate survival analysis, only tumor cell proliferation and lymph node status were significant in the final multivariate model. In conclusion, our findings indicate an important relationship not only between EZH2 and markers of tumor cell proliferation but also with aggressive disease. These findings might be practically important and relevant because the polycomb group proteins have recently been suggested as candidates for targeted therapy.Progression of breast cancer is a significant clinical problem and there is a need for novel treatment strategies. Although multiple prognostic factors have been reported, few markers, like c-erbB-2 status (Her2; ref. 1), have practical value as response predictors for targeted therapy (2). The enhancer of zeste homologue 2 (EZH2) is a member of the polycomb group of genes and has been involved in cell cycle regulation, and polycomb group proteins were recently suggested as candidates for targeted treatment (3). In human tumors, expression of EZH2 was first associated with hormone refractory and aggressive prostate cancer (4). In breast cancer, Kleer et al. (5) showed that EZH2 expression was increased in malignant tumors and promoted anchorage-independent and invasive growth in vitro, whereas proliferation was not significantly enhanced. EZH2 expression was further associated with increased tumor diameter, negative estrogen receptor (ER) and progesterone receptor (PR) status, and advanced stage of disease. Reduced patient survival was significantly predicted by EZH2 positivity in a subgroup of 194 cases. In a different study, Raaphorst et al. (6) found that EZH2 expression was associated with poorly differentiated and invasive breast cancers, whereas no clear relationship with proliferation was found. In this study, there was no prognostic effect of EZH2 expression.EZH2 is regulated by E2F transcription factors, which are liberated by retinoblastoma protein phosphorylation (7,8). Activated p53 down-regulates the EZH2 gene through repression of its promoter (9). Recently published cDNA microarray data i...

Recent studies have detailed the genomic landscape of primary endometrial cancers, but their evolution into metastases has not been characterized. We performed whole-exome sequencing of 98 tumor biopsies including complex atypical hyperplasias, primary tumors, and paired abdominopelvic metastases to survey the evolutionary landscape of endometrial cancer. We expanded and reanalyzed TCGA-data, identifying novel recurrent alterations in primary tumors, including mutations in the estrogen receptor cofactor NRIP1 in 12% of patients. We found that likely driver events tended to be shared by primary and metastatic tissue-samples, with notable exceptions such as ARID1A mutations. Phylogenetic analyses indicated that the sampled metastases typically arose from a common ancestral subclone that was not detected in the primary tumor biopsy. These data demonstrate extensive genetic heterogeneity within endometrial cancers and relative homogeneity across metastatic sites.

Interval breast cancer reduce the effectiveness of mammography screening programs. We studied 95 interval cancers, diagnosed during 1996 to 2001 as part of the populationbased Norwegian Breast Cancer Screening Program. These cases were matched on size (F F2.0 mm) to 95 screen-detected breast cancers, and the tumors were compared by immunohistochemical methods using tissue microarrays. Patients with interval cancers were more likely to be younger [odds ratio (OR), 4.7; P = 0.0001], to have dense breasts (OR, 3.4; P = 0.004), and to have estrogen receptor -negative tumors (OR, 2.6, P = 0.01), and p53 expression was more frequent (OR, 4.0; P = 0.001). Notably, interval cancers were more likely to have a basal epithelial phenotype, in that expression of cytokeratin 5/6 (OR, 2.3; P = 0.04) and Pcadherin (OR, 2.5; P = 0.04) was more frequent in interval cases than in size-matched, screen-detected tumors. In a logistic regression model, p53 expression, age, and breast density were independent predictors of interval cancers. Our data suggest that breast cancers with a basal epithelial phenotype are more likely than nonbasal breast cancers to present between regular mammograms. (Cancer Epidemiol Biomarkers Prev 2005;14(5):1108 -12)