patient derived xenografts

Overexpression and activation of the Epidermal Growth Factor Receptor (EGFR) have been linked to poor prognosis in several human cancers. Cetuximab is a monoclonal antibody against EGFR, that is used for the treatment in head and neck squamous cell carcinoma (HNSCC) and metastatic colorectal cancer. Unfortunately, most tumors have intrinsic or acquire resistance to cetuximab during the course of therapy. Honokiol is a natural compound found in the bark and leaves of the Chinese Magnolia tree and is established to have several anti-cancer properties without appreciable toxicity...

Oncogenic ALK fusions occur in several types of cancer and can be effectively treated with ALK inhibitors; however, ALK fusions and treatment response have not been characterized in malignant melanomas. Recently, a novel isoform of ALK (ALKATI) was reported in 11% of melanomas but the response of melanomas expressing ALKATI to ALK inhibition has not been well characterized. We analyzed 45 melanoma patient-derived xenograft models for ALK mRNA and protein expression. ALK expression was identified in 11 out of 45 (24...

Heterozygous mutations in NADP-dependent isocitrate dehydrogenases (IDH) define the large majority of diffuse gliomas and are associated with hypermethylation of DNA and chromatin. The metabolic dysregulations imposed by these mutations, whether dependent or not on the oncometabolite D-2-hydroxyglutarate (D2HG), are less well understood. Here, we applied mass spectrometry imaging on intracranial patient-derived xenografts of IDH-mutant versus IDH wild-type glioma to profile the distribution of metabolites at high anatomical resolution in situ This approach was complemented by in vivo tracing of labeled nutrients followed by liquid chromatography-mass spectrometry (LC-MS) analysis...

Animal models are essential to cancer research, but current xenograft models are limited in their utility especially due to the lack of an immune system. Here we demonstrate that a xenograft tumor model can be developed in immunocompetent mice by tolerizing murine fetuses to human tumor cells. A375 human melanoma cells were injected into day E14 fetuses and after birth mice were challenged with A375 cells to determine their ability to develop tumors. Intravenous injections of cells resulted in metastatic-like lung tumors, which were verified to be human in origin by immunohistochemistry and PCR...

Luteolin is a flavonoid compound derived from Lonicera japonica Thunb, which has been reported to exert anticancer effects on different types of tumors. miRNAs are a kind of endogenous non-coding small RNAs, which involved in occurrence and development of multi cancer, including miR-34a. However, the relationship between miR-34a and luteolin's susceptibility to cancer cells still remains unclear. In this study, we explored the roles of miR-34a and the effects of luteolin on GC cells as well as the underlying mechanism of miR-34a in mediating the susceptibility of GC cell to luteolin...

Glioblastoma are highly aggressive brain tumours that are associated with an extremely poor prognosis. Within these tumours exists a subpopulation of highly plastic self-renewing cancer cells that retain the ability to expand ex vivo as tumourspheres, induce tumour growth in mice, and have been implicated in radio- and chemo-resistance. Although their identity and fate are regulated by external cues emanating from endothelial cells, the nature of such signals remains unknown. Here, we used a mass spectrometry proteomic approach to characterize the factors released by brain endothelial cells...

The RUNX2 transcription factor promotes breast cancer growth and metastasis through interactions with a variety of cofactors that activate or repress target genes. Using a direct drug discovery approach we identified CADD522 as a small molecule that inhibits the DNA binding of the runt box domain protein, RUNX2. The current study defines the effect of CADD522 on breast cancer growth and metastasis, and addresses the mechanisms by which it exerts its anti-tumor activity. CADD522 treatment resulted in significant growth inhibition, clonogenic survival, tumorsphere formation, and invasion of breast cancer cells...

Children with neurofibromatosis type 1 (NF1) are predisposed to develop central nervous system neoplasms, the most common of which are low-grade gliomas (LGGs). The absence of human NF1 associated LGG-derived cell lines, coupled with an inability to generate patient-derived xenograft models, represents barriers to profile molecularly targeted therapies for these tumors. Thus, genetically engineered mouse models have been identified to evaluate the interplay between Nf1-deficient tumor cells and nonneoplastic stromal cells to evaluate potential therapies for these neoplasms...

Breast cancer is the second most common cancer and the most frequent cancer in women worldwide. Recent improvements in early detection and effective adjuvant chemotherapies have improved the survival of breast cancer patients. Even with initial disease remission, one-third of all breast cancer patients will relapse with distant metastasis. Breast cancer metastasis is largely an incurable disease and the main cause of death among breast cancer patients. Cancer metastasis is comprised of complex processes that are usually not controllable by intervention of a single molecular target...

HAb18G/CD147, an important marker in the progression of hepatocellular carcinoma (HCC), is highly expressed on the surface of HCC cells. To increase the therapeutic efficacy of Doxil (PEGylated liposomal doxorubicin) against HCC, we constructed CD147-targeted doxorubicin-loaded immunoliposomes (Anti-CD147 ILs-DOX) by conjugating F(ab')2 of a CD147-specific monoclonal antibody to DSPE-PEG-MAL, and then inserted the antibody-conjugated polymer to Doxil. Anti-CD147 ILs-DOX delivered DOX to CD147-overexpressing HCC cells specifically and efficiently in vitro and in vivo, resulting in enhanced therapeutic effects than non-targeted controls...

Patients with triple negative breast cancer have a poor prognosis due in part to the lack of targeted therapies. In the search for novel drugs, our laboratory has developed a second-generation curcumin derivative, 3,5-bis(3,4,5-trimethoxybenzylidene)-1-methylpiperidine-4-one (RL71), that exhibits potent in vitro cytotoxicity. To improve the clinical potential of this drug, we have encapsulated it in styrene maleic acid (SMA) micelles. SMA-RL71 showed improved biodistribution, and drug accumulation in the tumor increased 16-fold compared to control...

Pancreatic cancer is one of the most fatal types of cancer and is associated with a dismal prognosis. Gemcitabine-based chemotherapy is clinically used for the treatment of advanced pancreatic cancer. However, many forms of pancreatic cancer have acquired resistance to gemcitabine. In order to prevent patients from suffering from the side effects of chemotherapy and to have the chance to receive more effective intervention, assessment of whether the patient pancreatic cancer cells are resistant to gemcitabine before clinical practice is crucial...

Synovial sarcoma (SS) is an aggressive soft-tissue malignancy characterised by expression of SS18-SSX fusions, where treatment options are limited. To identify therapeutically actionable genetic dependencies in SS, we performed a series of parallel, high-throughput small interfering RNA (siRNA) screens and compared genetic dependencies in SS tumor cells to those in >130 non-SS tumour cell lines. This approach revealed a reliance of SS tumor cells upon the DNA damage response serine/threonine protein kinase ATR...

Cross-talk among oncogenic signaling and metabolic pathways may create opportunities for new therapeutic strategies in cancer. Here we show that although acute inhibition of EGFR-driven glucose metabolism induces only minimal cell death, it lowers the apoptotic threshold in a subset of patient-derived glioblastoma (GBM) cells. Mechanistic studies revealed that after attenuated glucose consumption, Bcl-xL blocks cytoplasmic p53 from triggering intrinsic apoptosis. Consequently, targeting of EGFR-driven glucose metabolism in combination with pharmacological stabilization of p53 with the brain-penetrant small molecule idasanutlin resulted in synthetic lethality in orthotopic glioblastoma xenograft models...

Colorectal cancer is associated with aberrant activation of the Wnt pathway. β-Catenin plays essential roles in the Wnt pathway by interacting with T-cell factor 4 (TCF4) to transcribe oncogenes. We synthesized a small molecule, referred to as HI-B1, and evaluated signaling changes and biological consequences induced by the compound. HI-B1 inhibited β-catenin/TCF4 luciferase activity and preferentially caused apoptosis of cancer cells in which the survival is dependent on β-catenin. The formation of the β-catenin/TCF4 complex was disrupted by HI-B1 due to the direct interaction of HI-B1 with β-catenin...

Sorafenib, the only approved drug for hepatocellular carcinoma, acts as a remarkable inhibitor of Raf serine-threonine kinases. However, Sorafenib is expensive, and clinical experience shows that it is not an effective treatment for many patients. Previous study has demonstrated that phosphorylated ERK (pERK) is a key downstream component in the RAF/MEK/ERK signaling pathway. Here, we investigate whether pERK is a useful biomarker for treating HCC with Sorafenib. In vitro cell viability assays showed that the efficacy of Sorafenib was distinctly different according to the level of pERK...

BACKGROUND: In acute myeloid leukaemia (AML)-affected patients, the presence of heterogeneous sub-clones at diagnosis has been shown to be responsible for minimal residual disease and relapses. The role played by the immune system in this leukaemic sub-clonal hierarchy and maintenance remains unknown. As leukaemic sub-clone immunogenicity could not be evaluated in human AML xenograft models, we assessed the sub-clonal diversity of the murine C1498 AML cell line and the immunogenicity of its sub-clones in immune-competent syngeneic mice...

Antagonists of MDM2-p53 interaction are emerging anti-cancer drugs utilized in clinical trials for malignancies that rarely mutate p53, including melanoma. We discovered that MDM2-p53 antagonists protect DNA from drug-induced damage in melanoma cells and patient-derived xenografts. Among the tested DNA damaging drugs were various inhibitors of Aurora and Polo-like mitotic kinases, as well as traditional chemotherapy. Mitotic kinase inhibition causes mitotic slippage, DNA re-replication, and polyploidy. Here we show that re-replication of the polyploid genome generates replicative stress which leads to DNA damage...

Notch pathways have important roles in carcinogenesis including pathways involving the Notch1 and Notch2 oncogenes. Pan-Notch inhibitors, such as gamma secretase inhibitors (GSIs), have been used in the clinical trials, but the outcomes of these trials have been insufficient and have yielded unclear. In the present study, we demonstrated that GSIs, such as MK-0752 and RO4929097, inhibit breast tumor growth, but increase the breast cancer stem cell (BCSC) population in Notch3-expressing breast cancer cells, in a process that is coupled with IL6 induction and is blocked by the IL6R antagonist Tocilizumab (TCZ)...

Mechanisms of acquired resistance to immune checkpoint inhibitors (ICIs) are poorly understood. We leveraged a collection of 14 ICI-resistant lung cancer samples to investigate whether alterations in genes encoding HLA Class I antigen processing and presentation machinery (APM) components or interferon signaling play a role in acquired resistance to PD-1 or PD-L1 antagonistic antibodies. Recurrent mutations or copy number changes were not detected in our cohort. In one case, we found acquired homozygous loss of B2M that caused lack of cell surface HLA class I expression in the tumor and a matched patient-derived xenograft (PDX)...