Publications by authors named "Melanie Bocanegra"

Epithelial-mesenchymal transition (EMT), a switch of polarized epithelial cells to a migratory, fibroblastoid phenotype, is considered a key process driving tumor cell invasiveness and metastasis. Using breast cancer cell lines as a model system, we sought to discover gene expression signatures of EMT with clinical and mechanistic relevance. A supervised comparison of epithelial and mesenchymal breast cancer lines defined a 200-gene EMT signature that was prognostic across multiple breast cancer cohorts.

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Background: Breast cancer cell lines have been used widely to investigate breast cancer pathobiology and new therapies. Breast cancer is a molecularly heterogeneous disease, and it is important to understand how well and which cell lines best model that diversity. In particular, microarray studies have identified molecular subtypes-luminal A, luminal B, ERBB2-associated, basal-like and normal-like-with characteristic gene-expression patterns and underlying DNA copy number alterations (CNAs).

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Breast cancer exhibits clinical and molecular heterogeneity, where expression profiling studies have identified five major molecular subtypes. The basal-like subtype, expressing basal epithelial markers and negative for estrogen receptor (ER), progesterone receptor (PR) and HER2, is associated with higher overall levels of DNA copy number alteration (CNA), specific CNAs (like gain on chromosome 10p), and poor prognosis. Discovering the molecular genetic basis of tumor subtypes may provide new opportunities for therapy.

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Background & Aims: Colon cancers with high-frequency microsatellite instability (MSI-H) develop frameshift mutations in tumor suppressors as part of their pathogenesis. ACVR2 is mutated at its exon 10 polyadenine tract in >80% of MSI-H colon cancers, coinciding with loss of protein. ACVR2 transmits the growth effects of activin via phosphorylation of SMAD proteins to affect gene transcription.

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