BackgroundColorectal cancer (CRC) is a heterogeneous and biologically poorly understood disease. To tailor CRC treatment, it is essential to first model this heterogeneity by defining subtypes of patients with homogeneous biological and clinical characteristics and second match these subtypes to cell lines for which extensive pharmacological data is available, thus linking targeted therapies to patients most likely to respond to treatment.MethodsWe applied a new unsupervised, iterative approach to stratify CRC tumor samples into subtypes based on genome-wide mRNA expression data. By applying this stratification to several CRC cell line panels and integrating pharmacological response data, we generated hypotheses regarding the targeted treatment of different subtypes.ResultsIn agreement with earlier studies, the two dominant CRC subtypes are highly correlated with a gene expression signature of epithelial-mesenchymal-transition (EMT). Notably, further dividing these two subtypes using iNMF (iterative Non-negative Matrix Factorization) revealed five subtypes that exhibit activation of specific signaling pathways, and show significant differences in clinical and molecular characteristics. Importantly, we were able to validate the stratification on independent, published datasets comprising over 1600 samples. Application of this stratification to four CRC cell line panels comprising 74 different cell lines, showed that the tumor subtypes are well represented in available CRC cell line panels. Pharmacological response data for targeted inhibitors of SRC, WNT, GSK3b, aurora kinase, PI3 kinase, and mTOR, showed significant differences in sensitivity across cell lines assigned to different subtypes. Importantly, some of these differences in sensitivity were in concordance with high expression of the targets or activation of the corresponding pathways in primary tumor samples of the same subtype.ConclusionsThe stratification presented here is robust, captures important features of CRC, and offers valuable insight into functional differences between CRC subtypes. By matching the identified subtypes to cell line panels that have been pharmacologically characterized, it opens up new possibilities for the development and application of targeted therapies for defined CRC patient sub-populations.

Purpose: To test the hypothesis that simultaneous, equipotent inhibition of epidermal growth factor receptor (EGFR; erbB1), erbB2 (human epidermal growth factor receptor 2), and erbB3 receptor signaling, using the novel small-molecule inhibitor AZD8931, will deliver broad antitumor activity in vitro and in vivo.Experimental Design: A range of assays was used to model erbB family receptor signaling in homodimers and heterodimers, including in vitro evaluation of erbB kinase activity, erbB receptor phosphorylation, proliferation in cells, and in vivo testing in a human tumor xenograft panel, with ex vivo evaluation of erbB phosphorylation and downstream biomarkers. Gefitinib and lapatinib were used to compare the pharmacological profile of AZD8931 with other erbB family inhibitors.Results: In vitro, AZD8931 showed equipotent, reversible inhibition of EGFR (IC 50 , 4 nmol/L), erbB2 (IC 50 , 3 nmol/L), and erbB3 (IC 50 , 4 nmol/L) phosphorylation in cells. In proliferation assays, AZD8931 was significantly more potent than gefitinib or lapatinib in specific squamous cell carcinoma of the head and neck and non-small cell lung carcinoma cell lines. In vivo, AZD8931 inhibited xenograft growth in a range of models while significantly affecting EGFR, erbB2, and erbB3 phosphorylation and downstream signaling pathways, apoptosis, and proliferation.Conclusions: AZD8931 has a unique pharmacologic profile providing equipotent inhibition of EGFR, erbB2, and erbB3 signaling and showing greater antitumor activity than agents with a narrower spectrum of erbB receptor inhibition in specific preclinical models. AZD8931 provides the opportunity to investigate whether simultaneous inhibition of erbB receptor signaling could be of utility in the clinic, particularly in the majority of solid tumors that do not overexpress erbB2. Clin Cancer Res; 16(4); 1159-69. ©2010 AACR.The erbB receptor family is composed of four related receptor tyrosine kinases [epidermal growth factor receptor (EGFR, erbB1), erbB2 (human epidermal growth factor receptor 2, HER2), erbB3 (HER3), and erbB4 (HER4)]. ErbB2 lacks ligand-binding capacity and erbB3 is intrinsically inactive as a kinase. There are two main ligand classes: the first bind specifically to EGFR whereas the second includes the neu differentiation factors, or heregulins, which bind erbB3 and erbB4 (1). In cancer, activation of erbB2 may arise by (a) receptor overexpression inducing homodimerization and (b) receptor heterodimerization with another family member, of which erbB3 is considered to be the preferred and most oncogenic partner (2).Homodimerization and/or heterodimerization of erbB receptors results in the phosphorylation of key tyrosine residues in the intracellular domain and leads to the stimulation of numerous intracellular signal transduction pathways involved in cell proliferation and survival (3, 4). The deregulation of erbB family signaling promotes proliferation, invasion, metastasis, angiogenesis, and tumor cell survival and has been described in many human cancers, in...

No abstract

No abstract

No abstract

Low-grade endometrial endometrioid adenocarcinomas (LGEECa) can recur in the vagina (VRec), pelvic and abdominal region (PARec), or distant sites (DMet). Tumor size, histopathologic features, and lymph node involvement at presentation have been linked to the development of these recurrences. However, the amount of information on risk factors to predict site of recurrence is limited. Methods: In this multi-institutional study, we analyzed data from 589 patients with FIGO grades 1 and 2 LGEECa and found 116 patients with VRec, PARec, or DMet. They were compared with 187 age-matched controls with negative lymph nodes, no adjuvant treatment, and no recurrences; mean follow-up times were 44 and 59 months, respectively. Cox proportional hazards analysis was used to identify univariable and multivariable risk factors for each type of recurrence (P b .05).Results: Forty-one patients had VRec, 33 had PARec (pelvic soft tissue, 14; abdominal tissue, 9; liver capsule, 5; retroperitoneum, 3; colorectal wall, 2), and 42 had DMet (lung, 19; lymph nodes, 17; bone and soft tissue, 5; brain, 1) as the initial site of recurrence. Univariate and multivariate analysis of histopathologic features are summarized in Table 1. In addition, features associated with vaginaonly recurrence included superficial myometrial invasion (P = .002); low nuclear grade (P = .03); lymphovascular invasion (LVI) adjacent to tumor, but not deeper than invasive tumor front (P b .001); less than 5% microcystic elongated and fragmented pattern (MELF) at invasive tumor front (P = .014); and no pelvic lymph node metastasis at presentation (P = .019). These features were not significantly different from controls. Conclusions: (1) Features of LGEECa that predicted VRec included superficialy invasive, low nuclear grade tumors with minimal MELF, minimal or no LVI, and no lymph node metastasis. These features were more closely related with tumors that did not recur than with recurrent tumors. (2) LGEECa with PARec differed from those with VRec, because the tumors were larger and deeply invasive and MELF at invasive tumor front, suggesting a different dissemination route than tumors with VRec. (3) Significant predictor features of LGEECa with DMet included intraglandular tumor necrosis, cell clusters at the invasive front and adjacent to areas of LVI, and cervical stromal involvement. The latter feature might be indicative of venous rather of lymphatic invasion.

HighlightsThe case presented is that of a primary debulking surgery for presumed ovarian cancer.Final pathology revealed diffusely metastatic endocervical adenocarcinoma.After primary chemotherapy, the patient has remained disease-free 30 months after surgery.

482 Background: Colorectal cancer (CRC) is generally stratified based on genetic and epigenetic features, such as KRAS mutation and microsatellite instability status. In order to facilitate the development of new targeted drugs and treatment regimens, it is important to redefine CRC at the molecular level by identifying subtypes that are relevant for response to targeted therapy. Methods: We applied a new unsupervised approach for iteratively stratifying tumor samples using genome-wide mRNA expression data. The resulting gene expression signatures were used to subtype CRC cell line panels and publicly available CRC tumor datasets. We employed pharmacological data on the cell line panels to link the subtypes to therapy response. Results: Starting from a gene expression dataset of 63 CRC tumor samples, we employed non-negative matrix factorization (NMF) and identified two dominant CRC subtypes. In agreement with previously published results, one of the types showed a mesenchymal and the other an epithelial-like gene expression pattern. In a second step, we applied NMF on these two dominant subtypes and further stratified them into two and three subtypes, respectively. The resulting five CRC subtypes show many differences, most notably activation of specific signaling pathways. Importantly, we recovered these five subtypes in several independent, publicly available CRC datasets. This strongly suggests that the signatures capture disease-relevant features of CRC. Furthermore, we found that the different subtypes corresponded to different cell lines in a panel of CRC cell lines. The clustered CRC cell lines displayed differential responses to a number of targeted compounds, indicating that the new CRC clusters may represent disease subtypes that of differential drug sensitivity. Conclusions: The CRC subtypes discovered using our new method offer new insights into the functional and molecular processes driving CRC. Furthermore, the evidence suggests that these subtypes may differ in activated pathway status and the response to some targeted inhibitors, indicating that targeting pathways conserved in these subtypes may provide new drug discovery opportunities.