Project description:Mice bearing primary human chondrosarcoma xenografts were treated with IPI 926, and mRNA levels of known Hh pathway genes and endpoint tumor volumes were measured. Gene expression profiling of IPI-926 treated tumors was conducted to identify potential novel Hh target genes. 4 Control treated and 4 IPI-926 treated NSG Mice. Primary tumor was obtained from a single chondrosarcoma patient.
Project description:Mice bearing primary human chondrosarcoma xenografts were treated with IPI 926, and mRNA levels of known Hh pathway genes and endpoint tumor volumes were measured. Gene expression profiling of IPI-926 treated tumors was conducted to identify potential novel Hh target genes.
Project description:Aberrant activation of Hedgehog pathway is responsible for initiation and maintenance of various cancers, including medulloblastoma (MB), basal cell carcinoma (BCC), and other solid and hematological tumors. Therefore, targeting Hh pathway represents promising therapeutic prospects for Hh-driven cancers. In recent years, tremendous efforts have been dedicated to the discovery of Hh pathway inhibitor. While the majority of Hh pathway inhibitors target the upstream membrane protein Smoothened (SMO). Here, we performed Next Generation Sequencing to reveal the target genes of Hh pathway by treating mouse SHH-subtype medulloblastoma cells (SmoWT) with SMO inhibitor (GDC0449) or DMSO.
Project description:The Sonic Hedgehog (Shh) pathway drives a subset of medulloblastomas, a malignant neuroectodermal brain cancer, and other cancers. Small-molecule Shh pathway inhibitors have induced tumor regression in mice and patients with medulloblastoma; however, drug resistance rapidly emerges, in some cases via de novo mutation of the drug target. Here we assess the response and resistance mechanisms to the natural product derivative saridegib in an aggressive Shh-driven mouse medulloblastoma model. In this model, saridegib treatment induced tumor reduction and significantly prolonged survival. Furthermore, the effect of saridegib on tumor-initiating capacity was demonstrated by reduced tumor incidence, slower growth, and spontaneous tumor regression that occurred in allografts generated from previously treated autochthonous medulloblastomas compared with those from untreated donors. Saridegib, a known P-glycoprotein (Pgp) substrate, induced Pgp activity in treated tumors, which likely contributed to emergence of drug resistance. Unlike other Smoothened (Smo) inhibitors, the drug resistance was neither mutation-dependent nor Gli2 amplification-dependent, and saridegib was found to be active in cells with the D473H point mutation that rendered them resistant to another Smo inhibitor, GDC-0449. The fivefold increase in lifespan in mice treated with saridegib as a single agent compares favorably with both targeted and cytotoxic therapies. The absence of genetic mutations that confer resistance distinguishes saridegib from other Smo inhibitors. P21 to P36 PtcC/C mice were randomized to receive either saridegib (20 mg/kg per dose) for 6 weeks or vehicle control [5% (2-hydroxylpropyl)-β-cyclodextrin (HPBCD)] for 3 weeks administered via daily i.p. injection. Triplicate total RNA samples were collected for each of the two conditions.
Project description:We determined the immune cell composition and their gene expression, by performing single-cell RNA sequencing (scRNA-seq), in anti-PD-L1-treated 2F8cis tumors, a hot and immunoresponsive ovarian murine tumor model, and anti-PD-L1-treated 2F8cis/CA-MSC tumors. We also evaluated the ability of hedgehog inhibitor (HHi) therapy to reverse CA-MSC effects. Adipose-derived mesenchymal stem cells (MSC) were cultured with 2F8cis, an ovarian mouse tumor cell line, to generate cancer-associated MSC (CA-MSC). 2F8cis tumor cell alone or 2F8cis/CA-MSCs co-cultured cells at ratio 1:1 were injected into C57BL/6J mice. Tumor infiltrating CD45+ cells were isolated from anti-PD-L1-treated 2F8cis (Group 1, n=3), anti-PD-L1-treated 2F8cis/CA-MSCs (Group 2, n=3), anti-PD-L1+ IPI-926-treated 2F8cis/CA-MSCs (Group 3, n=3) tumors. Samples were labeled with different TotalSeq oligo-conjugated antibodies and loaded into the Chromium instrument (10x Genomics). The resulting barcoded cDNAs were used to construct libraries. Single-cell cDNA libraries were then processed for RNA sequencing using an Illumina NextSeq-500 platform. Anti-PD-L1-treated 2F8cis/CA-MSC tumors showed a high number of Monocytes and macrophages over-expressing Ccr2 and Tgfbi when compared to anti-PD-L1 responsive 2F8cis tumors. Our results also indicated that IPI-926 restored response to anti-PD-L1 therapy decresing the expression of Ccr2 and Tgfbi both in monocytes and macrophages. Our study represents the first detailed analysis generated by RNA-seq technology of 2F8cis/CA-MSC+ enriched tumor transcriptomes, treated with anti-PDL1 alone or in combination with HHi, and compared with anti-PDL1-treated tumors. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles.
Project description:The intermediate filament protein Nestin serves as a biomarker for stem cells and has been used to identify subsets of cancer stem-like cells. However, the mechanistic contributions of Nestin to cancer pathogenesis are not understood. Here we report that Nestin binds the hedgehog pathway transcription factor Gli3 to mediate the development of medulloblastomas of the hedgehog subtype. In a mouse model system, Nestin levels increased progressively during medulloblastoma formation resulting in enhanced tumor growth. Conversely, loss of Nestin dramatically inhibited proliferation and promoted differentiation. Mechanistic investigations revealed that the tumor-promoting effects of Nestin were mediated by binding to Gli3, a zinc finger transcription factor that negatively regulates hedgehog signaling. Nestin binding to Gli3 blocked Gli3 phosphorylation and its subsequent proteolytic processing, thereby abrogating its ability to negatively regulate the hedgehog pathway. Our findings show how Nestin drives hedgehog pathway-driven cancers and uncover in Gli3 a therapeutic target to treat these malignancies. Nestin+ and Nestin- GNPs (granule neuron precursors) were purified from Nestin-CFP/Math1-Cre/Ptch1-loxp cerebella at postnatal day 4 by FACs, and total RNA from these two cell populations were extracted, and then labeled and hybridized to Affymetrix Mouse Genome 430 2.0 arrays.
Project description:Medulloblastoma is one of the most common malignant brain tumors of children, and 30% of medulloblastomas are driven by gain-of-function genetic lesions in the Sonic hedgehog (SHH) signaling pathway. Eyes Absent (EYA1), a haloacid dehalogenase (HAD) phosphatase and co-transcription factor, is critical for tumorigenesis and proliferation of SHH-medulloblastoma (SHH-MB). Benzarone and benzbromarone have been identified as allosteric inhibitors for the Eya proteins. Using benzarone as a point of departure, we developed a panel of 35 derivatives, and identified one new compound, DS-1-38, that functions as an Eya-antagonist, opposes SHH-signaling, inhibits SHH-MB growth in vitro and in vivo, shows excellent brain penetrance and increases the lifespan of mice predisposed to fatal SHH-MB. Our data suggest that DS-1-38 provides a path for developing targeted therapeutic for pediatric SHH-MB.
Project description:Medulloblastoma is one of the most common malignant brain tumors of children, and 30% of medulloblastomas are driven by gain-of-function genetic lesions in the Sonic hedgehog (SHH) signaling pathway. Eyes Absent (EYA1), a haloacid dehalogenase (HAD) phosphatase and co-transcription factor, is critical for tumorigenesis and proliferation of SHH-medulloblastoma (SHH-MB). Benzarone and benzbromarone have been identified as allosteric inhibitors for the Eya proteins. Using benzarone as a point of departure, we developed a panel of 35 derivatives, and identified one new compound, DS-1-38, that functions as an Eya-antagonist, opposes SHH-signaling, inhibits SHH-MB growth in vitro and in vivo, shows excellent brain penetrance and increases the lifespan of mice predisposed to fatal SHH-MB. Our data suggest that DS-1-38 provides a path for developing targeted therapeutic for pediatric SHH-MB.
Project description:Resistance to clinically available targeted drugs has become a critical issue in hedgehog-driven cancer treatment. Our previous studies have demonstrated two epigenetic/transcriptional targeted therapeutic strategies, BET inhibition and CDK7 inhibition, could overcome both primary and acquired resistance to Smoothened inhibitor (SMOi) drugs, providing a promising direction for novel anti-hedgehog drug development. In this study, we performed CRISPR-Cas9 screening of epigenetic/transcriptional targeted sgRNA library in hedgehog-driven medulloblastoma (SHH-MB) cells and combined with tumor dataset analyses to identify other potential epigenetic/transcriptional targeted strategies for treating aberrant hedgehog pathway and overcoming SMOi-resistance. Our results demonstrated structure specific recognition protein 1 (SSRP1), a subunit of Facilitates Chromatin Transcription (FACT) complex, was a hedgehog-induced essential oncogene and therapeutic target of hedgehog-driven cancer. FACT inhibitor CBL0137, which has entered human clinical trials against cancer, could effectively suppress multiple mouse and human hedgehog-driven cancer models that are either SMOi-responsive or -resistant both in vitro and in vivo. Mechanistically, CBL0137 exerted its anti-hedgehog activity mainly through targeting the transcription of GLI1/2, which are core transcription factors of hedgehog pathway. ChIP-qPCR analyses further revealed SSRP1 could bind to the promoter regions of GLI1/2, while CBL0137 treatment substantially disrupted these interactions. Moreover, CBL0137 could work synergistically with BET inhibitor or CDK7 inhibitor on antagonizing aberrant hedgehog pathway and growth of either SMOi-responsive or -resistant hedgehog-driven cancer models. Taken together, our study identified FACT inhibition as another promising epigenetic/transcriptional targeted therapeutic strategy for treating hedgehog-driven cancer and overcoming SMOi-resistance.