Project description:Identify therapeutic vulnerabilities of palbociclib resistance in metastatic breast cancer patient-derived xenograft models and identify key biomarkers that correlate with development of resistance to inform new treatment directions
Project description:Non-small-cell lung cancer (NSCLC) is the leading cause of cancer death worldwide. The high mortality is very often a consequence of its late diagnosis when the cancer is already locally advanced or has disseminated. Advances in the study of NSCLC tumors have been achieved by using in vivo models, such as patient-derived xenografts. Apart from drug screening, this approach may also be useful for study of the biology of the tumors. In the present study, surgically resected primary lung cancer samples (n = 33) were implanted in immunodeficient mice, and nine were engrafted successfully, including seven adenocarcinomas, one squamous-cell carcinoma, and one large-cell carcinoma. ADC tumors bearing the KRAS-G12C mutation were the most frequently engrafted in our PDX collection. Protein expression of vimentin, ezrin, and Ki67 were evaluated in NSCLC primary tumors and during serial transplantation by immunohistochemistry, using H-score. Our data indicated a more suitable environment for solid adenocarcinoma, compared to other lung tumor subtypes, to grow and preserve its architecture in mice, and a correlation between higher vimentin and ezrin expression in solid adenocarcinomas. A correlation between high vimentin expression and lung adenocarcinoma tumors bearing KRAS-G12C mutation was also observed. In addition, tumor evolution towards more proliferative and mesenchymal phenotypes was already observed in early PDX tumor passages. These PDX models provide a valuable platform for biomarker discovery and drug screening against tumor growth and EMT for lung cancer translational research.
Project description:To probe the tissue source (cancer cell VS stromal cell) of gene expression in the mixed tumor samples, we took advantage of a set of Urothelial Cancer patient-derived xenograft (PDX) models given that the transcriptome in these models is a mixture of human RNA (derived from cancer cells) and mouse RNA (derived from stromal cells).
Project description:Non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations do not respond to anti-PD-1 (L1) as well as tumors without an EGFR mutation. We showed in a xenograft mouse model of EGFR-mutated NSCLC that, neither durvalumab nor oleclumab alone inhibited tumor growth compared to the isotype control. In contrast, the combination of both antibodies significantly inhibited tumor growth and increased gene expressions that corresponded to inflammation and T cell function in tumors treated. We used microarrays to study gene expressions that corresponded to enhanced immune response in antibody-treated mice.
Project description:Mass spectrometry profiling of orthotopically transplanted breast cancer patient-derived xenograft (PDX) tumors prior to chemotherapy treatment.
Project description:Gene expression signature of EpCAMlow/PDPN+ and EpCAMhigh/PDPN- cancer cells in engineered human NSCLC HSAEC_4T53RD mouse xenograft model.
Project description:Background: Patient-derived xenograft (PDX) models are a useful tool in cancer biology research. However, the number of lung cancer PDXs is limited Results: In the present study, we successfully established ten PDXs, including three adenocarcinoma (AD), six squamous cell carcinoma (SQ) and one large cell carcinoma (LA), from 30 patients with non-small cell lung cancer (NSCLC) (18 AD, 10 SQ, and 2 LA), mainly in SHO mice (Crlj:SHO-PrkdcscidHrhr). Histology of SQ, advanced clinical stage (III-IV), status of lymph node metastasis (N2-3), and maximum standardized uptake value (SUVmax) ≧10 when evaluated using a delayed 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) scan, was associated with successful PDX establishment. Histological analyses revealed that PDXs showed a histology similar to that of patients’ surgically resected tumors (SRTs), while components of the microenvironments were replaced with murine cells after several passages. Next generation sequencing and microarray analyses demonstrated that after 2 to 6 passages, PDXs preserved the majority of the somatic mutations and mRNA expressions of the corresponding SRTs. Two out of three PDXs with AD histology had EGFR mutations (L858R or exon19 deletion) and were sensitive to EGFR tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib and osimertinib. Furthermore, in one of the two PDXs with an EGFR mutation, osimertinib resistance was induced that was associated with epithelial-to-mesenchymal transition. Conclusions: This study presented ten serially transplantable PDXs of NSCLC in SHO mice and demonstrated the use of PDXs with an EGFR mutation for analyses of EGFR-TKI resistance.