CIC-DUX4 sarcoma (CDS) is a group of rare, mesenchymal, small round cell tumours that harbour the unique CIC-DUX4 translocation, which causes aberrant gene expression. CDS exhibits an aggressive course and poor clinical outcome, thus novel therapeutic approaches are needed for CDS treatment. Although patient-derived cancer models are an essential modality to develop novel therapies, none currently exist for CDS. Thus, the present study successfully established CDS patient-derived xenografts and subsequently generated two CDS cell lines from the grafted tumours. Notably, xenografts were histologically similar to the original patient tumour, and the expression of typical biomarkers was confirmed in the xenografts and cell lines. Moreover, the xenograft tumours and cell lines displayed high Src kinase activities, as assessed by peptide-based tyrosine kinase array. Upon screening 119 FDA-approved anti-cancer drugs, we found that only actinomycine D and doxorubicin were effectively suppress the proliferation among the drugs for standard therapy for Ewing sarcoma. However, we identified molecular targeting reagents, such as bortezomib and crizotinib that markedly suppressed the growth of CDS cells. Our models will be useful modalities to develop novel therapeutic strategies against CDS.
Background/Aims: In platinum-based chemotherapy for ovarian cancer, acquired drug resistance is a frequent occurrence. Because recent studies have demonstrated that dysregulation of microRNAs (miRNAs) is partly responsible for the induction of acquired drug resistance in cancers, we hypothesized that correcting the dysregulation of key miRNAs would reverse the acquired resistance to platinum-based drugs in ovarian cancer. Methods: Cisplatin-resistant SKOV3 and A2780 ovarian cancer cell lines (SKOV3-R and A2780-R, respectively) were established by long-term exposure to cisplatin. MTT assays were performed to evaluate the viability of SKOV3, SKOV3-R, A2780, and A2780-R cells. Quantitative PCR was used to examine the expression of miR-139-5p in these cell lines. The regulatory mechanism was confirmed by western blot analysis and luciferase reporter assays. After treatment with miR-139-5p and cisplatin, mitochondrial membrane potential and apoptosis were measured by using flow cytometry. Interaction with c-Jun and activating transcription factor 2 (ATF2) was evaluated by co-immunoprecipitation. Expression of B-cell lymphoma-extra large (Bcl-xl) and activation of caspase-9 and caspase-3 were detected by western blotting. Results: Expression of miR-139-5p was decreased in SKOV3-R and A2780-R cells. Recovery of miR-139-5p increased the sensitivity of SKOV3-R and A2780-R cells to cisplatin treatment, inhibited the interaction of c-Jun and ATF2, and decreased Bcl-xl expression in SKOV3-R and A2780-R cells. Expression of miR-139-5p promoted cisplatin-induced mitochondrial apoptosis through binding the 3′ untranslated region of c-Jun mRNA. Conclusion: Recovery of miR-139-5p suppressed the expression of c-Jun and thus reversed cisplatin-resistance in ovarian cancer.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.