A Phase l Study of a Tumor-targeted Systemic Nanodelivery System, SGT-94, in Genitourinary Cancers.

Gene therapy development has been limited by our inability to target multifocal cancer with systemic delivery. We developed a systemically administered, tumor-targeted liposomal nanodelivery complex (SGT-94) carrying a plasmid encoding RB94, a truncated form of the RB gene. In preclinical studies, RB94 showed marked cytotoxicity against tumor but not normal cells. SGT-94 was administered intravenously in a first-in-man study in metastatic genitourinary cancer. Minimal side effects were observed; dose-limiting toxicity (DLT) has not been reached in 11 evaluable patients. There was evidence of clinical activity at the 2.4 mg dose with one complete remission (CR) and one partial remission (PR). The patient in CR was retreated upon progression and had a second PR. Furthermore, there was tumor-specific targeting of the SGT-94 complex. One patient had wedge resections of two lung metastases which demonstrated RB94 expression at the DNA level by polymerase chain reaction (PCR) and at the protein level by Western blotting, with no RB94 present in normal contiguous lung. In conclusion, systemically delivered SGT-94 showed evidence of selective tumor targeting and was well tolerated with evidence of clinical activity. Additional studies are warranted to explore the activity of this drug as a single agent and in combination therapy.

Use of electroconvulsive therapy in older Chinese psychiatric patients.

OBJECTIVE: Little is known about the use of electroconvulsive therapy (ECT) in older Chinese psychiatric patients. This study examined the frequency of ECT and the demographic and clinical correlates in older psychiatric patients hospitalized in a large psychiatric institution in Beijing, China. METHODS: This was a retrospective chart review of 2339 inpatients aged 60 years and older treated over a period of 8 years (2007-2013) in a university-affiliated psychiatric institution in Beijing. Sociodemographic and clinical data were collected from the electronic chart management system for discharged patients. RESULTS: The rate of ECT use was 28.1% in the whole sample; 37.9% in those with bipolar disorders, 43.6% in major depression, 21.2% in schizophrenia, and 10.7% in other diagnoses. ECT ("ECT group") was associated with 60-65-year age group, high risk for suicide and low risk for falls at the time of admission, use of mood stabilizers and antidepressants, lack of health insurance, and having major medical conditions and diagnosis of major depression. The above significant correlates explained 24.9% of the variance of ECT use (p < 0.001). CONCLUSIONS: In a major psychiatric hospital in China, the use of ECT was common among older patients. ECT use in older patients treated in other clinical settings warrants further investigations.

Low molecular weight cyclin E is associated with p27-resistant, high-grade, high-stage and invasive bladder cancer.

Expression of low molecular weight (LMW) isoforms of cyclin E is a strong predictor of poor outcome in patients with breast cancer. The purpose of this study was to examine the expression of full-length and LMW cyclin E in bladder cancer cell lines and patient tumors. We used western blotting, immunoprecipitation and kinase assays to examine the expression and activity of key cell cycle-regulatory proteins in various human bladder cell lines, both tumorigenic and non-tumorigenic. We also analyzed cyclin E expression, kinase activity and immune complex binding partners in 43 tissue samples from grade 2 and 3 transitional cell carcinomas. Cyclin E was overexpressed and LMW isoforms were present only in bladder cancer cells. Overexpression of LMW isoforms of cyclin E and increased cyclin E kinase activity were both significantly associated with tumorigenicity of the bladder cell lines (p = 0.005 and 0.022, respectively). Binding of the cyclin-dependent kinase inhibitors p21 and p27 to LMW cyclin E did not inhibit the kinase activity of cyclin E and cyclin-dependent kinase 2 in primary tumor samples overexpressing LMW cyclin E. Full-length and LMW cyclin E were significantly overexpressed in grade 3 tumors compared with grade 2 tumors (p = 0.004). Finally, LMW cyclin E levels were significantly associated with a non-papillary growth pattern (p = 0.031) and invasiveness (p = 0.021) of the bladder tumors and poor overall survival (p = 0.06). These results suggest that LMW cyclin E can be used as a new prognostic marker for bladder cancer.

Tumor-targeting nanocomplex delivery of novel tumor suppressor RB94 chemosensitizes bladder carcinoma cells in vitro and in vivo.

PURPOSE: RB94, a truncated form of RB110, has enhanced tumor suppressor potency and activity against all tumor types tested to date including bladder carcinoma. However, efficient, systemic delivery of the gene encoding RB94 specifically to tumors, is an obstacle to clinical application as an anticancer therapeutic. We have developed a systemically given, nanosized liposome DNA delivery system that specifically targets primary and metastatic disease. The ability of RB94, delivered via this nanocomplex, to sensitize bladder carcinoma to chemotherapy in vitro and in vivo was assessed. EXPERIMENTAL DESIGN: The nanocomplex is an RB94 plasmid encapsulated by a cationic liposome, the surface of which is decorated with a tumor-targeting moiety, either transferrin (Tf/Lip/RB94) or an antitransferrin receptor single-chain antibody fragment (TfRScFv/Lip/RB94). The ability of the complex to sensitize human bladder carcinoma HTB-9 cells to chemotherapeutics was assessed in vitro by XTT assay. In vivo tumor specificity and efficacy were tested in mice carrying HTB-9 tumors by PCR and tumor growth inhibition, respectively. RESULTS: Transfection with Tf/Lip/RB94 significantly sensitized HTB-9 cells to chemotherapeutic agents in vitro. Tumor specificity of the complex was shown in an orthotopic bladder tumor model by immunohistochemistry and PCR. Moreover, in mice bearing subcutaneous HTB-9 tumors, the combination of systemically given Tf/Lip/RB94 or TfRScFv/Lip/RB94 plus gemcitabine resulted in significant (P<0.0005) tumor growth inhibition/regression and induction of apoptosis. CONCLUSIONS: Use of our tumor-targeting nanocomplex to specifically deliver the potent tumor suppressor RB94 efficiently to tumors has potential as a more effective treatment modality for genitourinary and other cancers.

Phosphorylation of Thr18 and Ser20 of p53 in Ad-p53-induced apoptosis.

The p53 protein plays a critical role in inducing cell cycle arrest or apoptosis. Because p53 is inactivated in human gliomas, restoring p53 function is a major focus of glioma therapy. The most clinically tested strategy for replacing p53 has been adenoviral-mediated p53 gene therapy (Ad-p53). In addition to their therapeutic implications, investigations into Ad-p53 provide model systems for understanding p53's ability to induce cell cycle arrest versus apoptosis, particularly because wild-type p53 cells are resistant to Ad-p53-induced apoptosis. Here we use Ad-p53 constructs to test the hypothesis that simultaneous phosphorylation of p53 at threonine 18 (Thr18) and serine 20 (Ser20) is causally associated with p53-mediated apoptosis. Studies using phosphorylation-specific antibodies demonstrated that p53-induced apoptosis correlates with phosphorylation of p53 at Thr18 and Ser20 but not with carboxy-terminal phosphorylation (Ser392). To prove a causal relationship between apoptosis and Thr18 and Ser20 phosphorylation of p53, the effects of an adenoviral p53 construct that was not phosphorylated (Ad-p53) was compared with a Thr18/Ser20 phosphomimetic construct (Ad-p53-18D20D) in wild-type p53 gliomas. Whereas treatment with Ad-p53 resulted only in cell cycle arrest, treatment with Ad-p53-18D20D induced dramatic apoptosis. Microarray and Western blot analyses showed that only Ad-p53-18D20D was capable of inducing expression of apoptosis-inducing proteins. Chromatin immunoprecipitation assays indicated that the protein product of Ad-p53-18D20D, but not Ad-p53, was capable of binding to apoptosis-related genes. We thus conclude that phosphorylation of Thr18 and Ser20 is sufficient for inducing p53-mediated apoptosis in glioma cells. These results have implications for p53 gene therapy and inform other strategies that aim to restore p53 function.

A phase I clinical trial of single-dose intrapleural IFN-beta gene transfer for malignant pleural mesothelioma and metastatic pleural effusions: high rate of antitumor immune responses.

PURPOSE: This phase 1 dose escalation study evaluated the safety and feasibility of single-dose intrapleural IFN-beta gene transfer using an adenoviral vector (Ad.IFN-beta) in patients with malignant pleural mesothelioma (MPM) and metastatic pleural effusions (MPE). EXPERIMENTAL DESIGN: Ad.IFN-beta was administered through an indwelling pleural catheter in doses ranging from 9 x 10(11) to 3 x 10(12) viral particles (vp) in two cohorts of patients with MPM (7 patients) and MPE (3 patients). Subjects were evaluated for (a) toxicity, (b) gene transfer, (c) humoral, cellular, and cytokine-mediated immune responses, and (d) tumor responses via 18-fluorodeoxyglucose-positron emission tomography scans and chest computed tomography scans. RESULTS: Intrapleural Ad.IFN-beta was generally well tolerated with transient lymphopenia as the most common side effect. The maximally tolerated dose achieved was 9 x 10(11) vp secondary to idiosyncratic dose-limiting toxicities (hypoxia and liver function abnormalities) in two patients treated at 3 x 10(12) vp. The presence of the vector did not elicit a marked cellular infiltrate in the pleural space. Intrapleural levels of cytokines were highly variable at baseline and after response to gene transfer. Gene transfer was documented in 7 of the 10 patients by demonstration of IFN-beta message or protein. Antitumor immune responses were elicited in 7 of the 10 patients and included the detection of cytotoxic T cells (1 patient), activation of circulating natural killer cells (2 patients), and humoral responses to known (Simian virus 40 large T antigen and mesothelin) and unknown tumor antigens (7 patients). Four of 10 patients showed meaningful clinical responses defined as disease stability and/or regression on 18-fluorodeoxyglucose-positron emission tomography and computed tomography scans at day 60 after vector infusion. CONCLUSIONS: Intrapleural instillation of Ad.IFN-beta is a potentially useful approach for the generation of antitumor immune responses in MPM and MPE patients and should be investigated further for overall clinical efficacy.

Syn3 provides high levels of intravesical adenoviral-mediated gene transfer for gene therapy of genetically altered urothelium and superficial bladder cancer.

Using our model to grow superficial human bladder cancer in the mouse bladder, we have found that the polyamide compound, Syn3, when injected intravesically for 1 hour at 1 mg/mL on two consecutive days, markedly increases rAd-beta-gal intravesical gene transfer and expression. This enhanced transgene expression was much greater than obtain by the use of 22% ethanol, which had previously been shown to increase intravesical adenoviral gene transfer, whereas little or no gene expression was seen with exposure to only rAd-beta-gal. beta-Galactosidase staining was seen in virtually every normal urothelial and superficial tumor cell present, including tumors that express little or no coxsackie-adenovirus receptors when Syn3 was present. High adenoviral-mediated gene transfer was also documented in the pig bladder using Syn3 in a similar protocol. Therefore, Syn3 may overcome the limitations of adequate intravesical adenoviral-mediated gene transfer and, when combined with an appropriate adenoviral-mediated gene, could offer an effective approach to the treatment of superficial bladder cancer and perhaps even genetically altered precursor lesions.