Resistance to receptor-blocking therapies primes tumors as targets for HER3-homing nanobiologics.

Resistance to anti-tumor therapeutics is an important clinical problem. Tumor-targeted therapies currently used in the clinic are derived from antibodies or small molecules that mitigate growth factor activity. These have improved therapeutic efficacy and safety compared to traditional treatment modalities but resistance arises in the majority of clinical cases.

Evaluation of venous thrombosis and tissue factor in epithelial ovarian cancer.

Objective: Ovarian clear cell carcinoma (OCCC) and high grade serous ovarian cancer (HGSOC) are associated with the highest risk of VTE among patients with epithelial ovarian cancer (EOC). Tissue factor (TF) is a transmembrane glycoprotein which can trigger thrombosis. We sought to evaluate if there is an association between VTE and tumor expression of tissue factor (TF), plasma TF, and microvesicle TF (MV TF) activity in this high-risk population.

Sphingosine kinase 1 is required for TGF-β mediated fibroblastto- myofibroblast differentiation in ovarian cancer.

Sphingosine kinase 1 (SPHK1), the enzyme that produces sphingosine 1 phosphate (S1P), is known to be highly expressed in many cancers. However, the role of SPHK1 in cells of the tumor stroma remains unclear. Here, we show that SPHK1 is highly expressed in the tumor stroma of high-grade serous ovarian cancer (HGSC), and is required for the differentiation and tumor promoting function of cancer-associated fibroblasts (CAFs).

Suboptimal cytoreduction in ovarian carcinoma is associated with molecular pathways characteristic of increased stromal activation.

Objective: Suboptimal cytoreductive surgery in advanced epithelial ovarian cancer (EOC) is associated with poor survival but it is unknown if poor outcome is due to the intrinsic biology of unresectable tumors or insufficient surgical effort resulting in residual tumor-sustaining clones. Our objective was to identify the potential molecular pathway(s) and cell type(s) that may be responsible for suboptimal surgical resection.

Methods: By comparing gene expression in optimally and suboptimally cytoreduced patients, we identified a gene network associated with suboptimal cytoreduction and explored the biological processes and cell types associated with this gene network.

Cyclin E1 and RTK/RAS signaling drive CDK inhibitor resistance via activation of E2F and ETS.

High-grade serous ovarian cancers (HGSOC) are genomically complex, heterogeneous cancers with a high mortality rate, due to acquired chemoresistance and lack of targeted therapy options. Cyclin-dependent kinase inhibitors (CDKi) target the retinoblastoma (RB) signaling network, and have been successfully incorporated into treatment regimens for breast and other cancers. Here, we have compared mechanisms of response and resistance to three CDKi that target either CDK4/6 or CDK2 and abrogate E2F target gene expression.

Chemotherapy targeting by DNA capture in viral protein particles.

Aim: This study tests the hypothesis that DNA intercalation and electrophilic interactions can be exploited to noncovalently assemble doxorubicin in a viral protein nanoparticle designed to target and penetrate tumor cells through ligand-directed delivery. We further test whether this new paradigm of doxorubicin targeting shows therapeutic efficacy and safety in vitro and in vivo.

Materials & Methods: We tested serum stability, tumor targeting and therapeutic efficacy in vitro and in vivo using biochemical, microscopy and cytotoxicity assays.

Indole-3-carbinol synergistically sensitises ovarian cancer cells to bortezomib treatment.

Background: Bortezomib is a proteasome inhibitor with minimal clinical activity as a monotherapy in solid tumours, but its combination with other targeted therapies is being actively investigated as a way to increase its anticarcinogenic properties. Here, we evaluate the therapeutic potential of co-treatment with bortezomib and indole-3-carbinol (I3C), a natural compound found in cruciferous vegetables, in human ovarian cancer.

Methods: We examined the effects of I3C, bortezomib and cisplatin in several human ovarian cancer cell lines.

A mechanistic study of tumor-targeted corrole toxicity.

HerGa is a self-assembled tumor-targeted particle that bears both tumor detection and elimination activities in a single, two-component complex (Agadjanian et al. Proc. Natl.

Xeroderma pigmentosum complementation group C single-nucleotide polymorphisms in the nucleotide excision repair pathway correlate with prolonged progression-free survival in advanced ovarian cancer.

Background: The nucleotide excision repair (NER) pathway is the principal DNA repair pathway for removing bulky platinum DNA adducts. Suboptimal DNA repair may lead to improved response to platinum agents. The objective of this study was to determine whether single-nucleotide polymorphisms (SNPs) in NER pathway genes could be markers of platinum response in ovarian cancer.

Tumor detection and elimination by a targeted gallium corrole.

Sulfonated gallium(III) corroles are intensely fluorescent macrocyclic compounds that spontaneously assemble with carrier proteins to undergo cell entry. We report in vivo imaging and therapeutic efficacy of a tumor-targeted corrole noncovalently assembled with a heregulin-modified protein directed at the human epidermal growth factor receptor (HER). Systemic delivery of this protein-corrole complex results in tumor accumulation, which can be visualized in vivo owing to intensely red corrole fluorescence.

Large Field of View Scanning Fluorescence Lifetime Imaging System for Multimode Optical Imaging of Small Animals.

We describe a scanning fluorescence lifetime imaging (SFLIM) system that provides a large field of view (LFOV), using a femtosecond (fs) pulsed laser, for multi-mode optical imaging of small animals. Fluorescence lifetime imaging (FLIM) can be a useful optical method to distinguish between fluorophores inside small animals. However, difficulty arises when LFOV is required in FLIM using a fs pulsed laser for the excitation of the fluorophores at low wavelengths (<500nm), primarily because the field of view of the pulsed blue excitation light generated from the second harmonic of the fs pulsed light is limited to about a centimeter in diameter due to the severe scattering and absorption of the light inside tissues.

Corroles that bind with high affinity to both apo and holo transferrin.

The interactions of transferrin (Tf) with the water soluble corrole 1 and with its gallium (1-Ga) and manganese (1-Mn) complexes were studied to establish the possible utilization of corrole-transferrin conjugates for targeting these corroles to cells that express the transferrin receptor. The protein, in both its iron-free apo form (apoTf) and the iron-bound holo form (holoTf), was found to spontaneously bind all three derivatives. This conclusion was reached from titrations followed by several spectroscopic methods and dilution experiments measured by fluorescence.

Effective high-capacity gutless adenoviral vectors mediate transgene expression in human glioma cells.

Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.

Typical and atypical trafficking pathways of Ad5 penton base recombinant protein: implications for gene transfer.

The adenovirus (Ad) penton base protein facilitates viral infection by binding cell surface integrins, triggering receptor-mediated endocytosis and mediating endosomal penetration. Given these multiple functions, recombinant penton base proteins have been utilized as non-viral vehicles for gene transfer by our lab and others. Although we have previously demonstrated that penton base-derived vectors undergo integrin-specific binding and cell entry, less than desirable levels of gene expression have led us to re-evaluate the recombinant penton base as an agent for gene delivery.

Specific delivery of corroles to cells via noncovalent conjugates with viral proteins.

Purpose: Corroles are amphiphilic macrocycles that can bind and transport metal ions, and thus may be toxic to cells. We predicted that anionic corroles would poorly enter cells due to the negatively charged cell membrane, but could be ideal tumor-targeted drugs if appropriate carriers enabled delivery into tumor cells. In this work, we test the hypothesis that recombinant cell penetrating proteins of the adenovirus (Ad) capsid form noncovalent conjugates with corroles to facilitate target-specific delivery and cell death.

Regulatable gutless adenovirus vectors sustain inducible transgene expression in the brain in the presence of an immune response against adenoviruses.

In view of recent serious adverse events and advances in gene therapy technologies, the use of regulatable expression systems is becoming recognized as indispensable adjuncts to successful clinical gene therapy. In the present work we optimized high-capacity adenoviral (HC-Ad) vectors encoding the novel tetracycline-dependent (TetOn)-regulatory elements for efficient and regulatable gene expression in the rat brain in vivo. We constructed two HC-Ad vectors encoding beta-galactosidase (beta-gal) driven by a TetOn system containing the rtTAS(s)M2 transactivator and the tTS(Kid) repressor under the control of the murine cytomegalovirus (mCMV) (HC-Ad-mTetON-beta-Gal) or the human CMV (hCMV) promoter (HC-Ad-hTetON-beta-Gal).

The Ad5 fiber mediates nonviral gene transfer in the absence of the whole virus, utilizing a novel cell entry pathway.

The interesting discovery reported here that soluble adenovirus serotype 5 (Ad5) fiber proteins enter cells without the virus was a serendipitous result during our development of Ad5 capsid proteins as nonviral gene transfer vectors. The Ad5 capsid fiber and penton proteins mediate infection. The fiber docks to a noninternalizing cell surface protein called the coxsackievirus-Ad receptor (CAR), followed by penton binding to integrins, triggering integrin-mediated endocytosis of the virus.