Loss of microRNA-21 leads to profound stromal remodeling and short survival in K-Ras-driven mouse models of pancreatic cancer.

The microenvironment of pancreatic cancer adenocarcinoma (PDAC) is highly desmoplastic with distinct tumor-restraining and tumor-promoting fibroblast subpopulations. Re-education rather than indiscriminate elimination of these fibroblasts has emerged as a new strategy for combination therapy. Here, we studied the effects of global loss of profibrotic noncoding regulatory microRNA-21 (miR-21) in K-Ras-driven p53-deleted genetically engineered mouse models of PDAC.

Patient-Derived Xenograft Models of Colorectal Cancer: Procedures for Engraftment and Propagation.

Preclinical compounds tested in animal models often demonstrate limited efficacy when transitioned into patients. As a result, individuals are assigned to treatment regimens that may be ineffective at treating their disease. The development of more clinically relevant models, such as patient-derived xenografts (PDXs), will (1) more completely mimic the human condition and (2) more accurately predict tumor responses to previously untested therapeutics.

Melanoma patient derived xenografts acquire distinct Vemurafenib resistance mechanisms.

Variable clinical responses, tumor heterogeneity, and drug resistance reduce long-term survival outcomes for metastatic melanoma patients. To guide and accelerate drug development, we characterized tumor responses for five melanoma patient derived xenograft models treated with Vemurafenib. Three BRAF(V600E) models showed acquired drug resistance, one BRAF(V600E) model had a complete and durable response, and a BRAF(V600V) model was expectedly unresponsive.

Anoikis-resistant subpopulations of human osteosarcoma display significant chemoresistance and are sensitive to targeted epigenetic therapies predicted by expression profiling.

Background: Osteosarcoma (OS) is the most common type of solid bone cancer, with latent metastasis being a typical mode of disease progression and a major contributor to poor prognosis. For this to occur, cells must resist anoikis and be able to recapitulate tumorigenesis in a foreign microenvironment. Finding novel approaches to treat osteosarcoma and target those cell subpopulations that possess the ability to resist anoikis and contribute to metastatic disease is imperative.

Establishment of genetically diverse patient-derived xenografts of colorectal cancer.

Preclinical compounds tested in animal models often show limited efficacy when transitioned into human clinical trials. As a result, many patients are stratified into treatment regimens that have little impact on their disease. In order to create preclinical models that can more accurately predict tumor responses, we established patient-derived xenograft (PDX) models of colorectal cancer (CRC).