Preclinical evaluation of a gene therapy treatment for transitional cell carcinoma

A simple and feasible atom-precise biotinylated Cu(i) complex for tumor-targeted chemodynamic therapy

A simple and feasible atom-precise biotinylated Cu(i) complex, which can catalyze H₂O₂ overexpressed commonly in the tumor microenvironment to produce ˙OH through a Fenton-like reaction, was prepared and employed as an effective agent for tumor-targeted chemodynamic therapy.

A gadolinium-complex-based theranostic prodrug for in vivo tumour-targeted magnetic resonance imaging and therapy

A molecular theranostic prodrug for treatment of tumour and real-time monitoring via MRI in vivo was reported.

Systematic Review: Characteristics and Preclinical Uses of Bladder Cancer Cell Lines

BACKGROUND

Bladder cancer (BC) cell lines are indispensable in basic and preclinical research. Currently, an up-to-date and comprehensive overview of available BC cell lines is not available.

OBJECTIVE

To provide an overview and resources on the origin, pathological and molecular characteristics of commonly used human, murine and canine BC cell lines.

METHODS

A PubMed search was performed for relevant articles published between 1980 and 2017 according to the following MeSH terms: cell line; cell line, tumor; urinary bladder neoplasms; carcinoma, transitional cell. The Cellosaurus database was searched, using the term "bladder" and/or "urothelial carcinoma". We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

We provide information on 157 human, murine and canine BC cell lines. 103 human BC cell lines have molecular data available, of which 69 have been profiled by at least one "omic" technology. We outline how these cell lines are currently being used for in vitro and in vivo experimental models. These results allow direct comparison of BC cell lines to patient samples, providing information needed to make informed decisions on the most genomically appropriate cell line to answer research questions. Furthermore, we show that cross-contamination remains an issue and describe guidelines for prevention.

CONCLUSIONS

In the BC field, multiple human, murine and canine BC cell lines have been developed and many have become indispensable for in vitro and in vivo research. High-throughput -omic technologies have dramatically increased the amount of molecular data on these cell lines. We synthesized a comprehensive overview of these data as a resource for the BC scientific community.

Cancer-specific promoters for expression-targeted gene therapy: ran, brms1 and mcm5

BACKGROUND

To expand the library of promoters that can be used for expression-targeted gene delivery to cancer cells, the specificity and strength of expression of three cancer-related gene promoters was evaluated: RAS-related nuclear protein ((P) ran), breast cancer metastasis suppressor 1 ((P) brms1) and minichromosome maintenance complex component 5 ((P) mcm5).

METHODS

The expression of reporter genes under the control of these promoters demonstrated selectivity in cancer cell lines of breast, prostate and ovarian origins versus a panel of normal cell types. The (P) ran was next used to regulate the expression of a bioactive exon (a constitutively active form of human caspase 3) to induce apoptosis in cancer cells. Further evaluation was performed in an orthotopic model of murine bladder cancer.

RESULTS

The average strengths of reporter expression had relative intensities of 99.8% ((P) ran), 87.7% ((P) brms1) and 55.8% ((P) mcm5) versus the strong (P) cmv-driven positive control. Comparisons of expression-targeted reporter gene expression for these three promoters versus the clinically interesting promoter for the human telomerase reverse transcriptase gene ((P) hTERT) yielded an improvement of two- to 15-fold. Following transfection, cell death was evident from morphologic observations and viability assays performed on the cancer cells lines, with little (if any) effects seen when the same genes were delivered to normal cells. Cell viability was reduced by up to 60% after one treatment, with cell death via apoptosis implied by caspase 3 detection. During the in vivo preclinical study, reduced tumor burden, lack of mineralization and decreased inflammation were demonstrated after only three treatments.

CONCLUSIONS

The ran, brms1, and mcm5 promoters have the specificity and strength needed for cancer-specific expression-targeted gene therapy. (p) ran in particular produced exciting results when coupled with a version of the caspase 3 exon to treat bladder cancer. Copyright © 2016 John Wiley & Sons, Ltd.

Non-invasive detection of bladder cancer via expression-targeted gene delivery

BACKGROUND

Because of the time and expense associated with the procedures and possible distress to the patient, cystoscopy or other imaging techniques are typically not used for bladder cancer detection before symptoms become present. Alternatively, commercial assays for urinary tumor markers exist but are marred by low sensitivity and high cost. There is a need for a simple and sensitive means of tumor detection, such as via the analysis of urine.

METHODS

Plasmids encoding the secretable reporter Gaussia Luciferase (G.LUC), under the control of cmv, cox2 or opn promoters, were delivered via polyethylenimine into bladder tumor cells in culture and into the bladders of mice. Expression profiles of the reporter were recorded, the optimal times for reporter detection were determined and the relationship of reporter expression with tumor size was calculated.

RESULTS

In vitro results showed that both the cox2 and opn promoters can drive significant expression of G.LUC in bladder carcinoma cells in a targeted fashion. In vivo results demonstrated that the cox2 promoter caused expression of G.LUC at detectable levels in the urine, with local signal maxima occurring at 48 and 72 h post-transfection. G.LUC levels in the urine had a 24-h periodicity, with the periodicity partly being the result of an agent secreted by tumor cells that served to mask the luciferase signal.

CONCLUSIONS

Having shown tumor specificity and having been calibrated with respect to circadian expression patterns, the detection system shows great promise for future investigation of tumor presence both in the urinary bladder and other models of cancer.

Preclinical evaluation of VAX-IP, a novel bacterial minicell-based biopharmaceutical for nonmuscle invasive bladder cancer

The development of new therapies that can prevent recurrence and progression of nonmuscle invasive bladder cancer remains an unmet clinical need. The continued cost of monitoring and treatment of recurrent disease, along with its high prevalence and incidence rate, is a strain on healthcare economics worldwide. The current work describes the characterization and pharmacological evaluation of VAX-IP as a novel bacterial minicell-based biopharmaceutical agent undergoing development for the treatment of nonmuscle invasive bladder cancer and other oncology indications. VAX-IP minicells selectively target two oncology-associated integrin heterodimer subtypes to deliver a unique bacterial cytolysin protein toxin, perfringolysin O, specifically to cancer cells, rapidly killing integrin-expressing murine and human urothelial cell carcinoma cells with a unique tumorlytic mechanism. The in vivo pharmacological evaluation of VAX-IP minicells as a single agent administered intravesically in two clinically relevant variations of a syngeneic orthotopic model of superficial bladder cancer results in a significant survival advantage with 28.6% (P = 0.001) and 16.7% (P = 0.003) of animals surviving after early or late treatment initiation, respectively. The results of these preclinical studies warrant further nonclinical and eventual clinical investigation in underserved nonmuscle invasive bladder cancer patient populations where complete cures are achievable.

The Synthesis of Cyclic Poly(ethylene imine) and Exact Linear Analogues: An Evaluation of Gene Delivery Comparing Polymer Architectures

The delivery of genetic material to cells offers the potential to treat many genetic diseases. Cationic polymers, specifically poly(ethylene imine) (PEI), are promising gene delivery vectors due to their inherent ability to condense genetic material and successfully affect its transfection. However, PEI and many other cationic polymers also exhibit high cytotoxicity. To systematically study the effect of polymer architecture on gene delivery efficiency and cell cytotoxicity, a set of cyclic PEIs were prepared for the first time and compared to a set of linear PEIs of the exact same molecular weight. Subsequent in vitro transfection studies determined a higher transfection efficiency for each cyclic PEI sample when compared to its linear PEI analogue in addition to reduced toxicity relative to the branched PEI "gold standard" control. These results highlight the critical role that the architecture of PEI can play in both optimizing transfection and reducing cell toxicity.

Advances in intravesical therapy for the treatment of non-muscle invasive bladder cancer (Review)

The knowledge of tumor biology and the biomechanical properties of the urothelium have led to significant advances in the development of intravesical therapy for the treatment of non-muscle invasive bladder cancer (NMIBC). Targeted therapy improves the efficacy and decreases the side effects of antineoplastic agents. Nanoparticles that target antitumor agents to the urothelial cells have allowed for improved delivery of these agents to tumor cells. Gene therapy is another strategy that has allowed for a targeted induction of an antitumor response. Finally, engineering of the bacillus Calmette-Guérin (BCG) vaccine aimed to minimize the potential side effects associated with this treatment. These novel approaches hold promise for decreasing the rate of progression and recurrence of NMIBC.

Clinical applications of recent molecular advances in urologic malignancies: no longer chasing a "mirage"?

As our understanding of the molecular events leading to the development and progression of genitourologic malignancies, new markers of detection, prognostication, and therapy prediction can be exploited in the management of these prevalent tumors. The current review discusses the recent advances in prostate, bladder, renal, and testicular neoplasms that are pertinent to the anatomic pathologist.

Molecular Pathology of Bladder Cancer

This article focuses on several promising candidate biomarkers that may soon make their transition to the realm of clinical management of bladder cancer. Presented are superficial and muscle-invasive urothelial carcinoma of the bladder and the genetic tests currently available in testing for diagnosis and prognosis of these diseases.

Emerging critical role of molecular testing in diagnostic genitourinary pathology

CONTEXT

The unprecedented advances in cancer genetics and genomics are rapidly affecting clinical management and diagnostics in solid tumor oncology. Molecular diagnostics is now an integral part of routine clinical management in patients with lung, colon, and breast cancer. In sharp contrast, molecular biomarkers have been largely excluded from current management algorithms of urologic malignancies.

OBJECTIVE

To discuss promising candidate biomarkers that may soon make their transition to the realm of clinical management of genitourologic malignancies. The need for new treatment alternatives that can improve upon the modest outcome so far in patients with several types of urologic cancer is evident. Well-validated prognostic molecular biomarkers that can help clinicians identify patients in need of early aggressive management are lacking. Identifying robust predictive biomarkers that will stratify response to emerging targeted therapeutics is another crucially needed development. A compiled review of salient studies addressing the topic could be helpful in focusing future efforts.

DATA SOURCES

A PubMed (US National Library of Medicine) search for published studies with the following search terms was conducted: molecular , prognostic , targeted therapy , genomics , theranostics and urinary bladder cancer , prostate adenocarcinoma , and renal cell carcinoma . Articles with large cohorts and multivariate analyses were given preference.

CONCLUSIONS

Our recent understanding of the complex molecular alterations involved in the development and progression of urologic malignancies is yielding novel diagnostic and prognostic molecular tools and opening the doors for experimental targeted therapies for these prevalent, frequently lethal solid tumors.

Antitumor effects of bladder cancer-specific adenovirus carrying E1A-androgen receptor in bladder cancer

The high frequency of recurrence and poor survival rate of bladder cancer demand exploration of novel strategies. Gene therapy via adenovirus has shown promising potential for the treatment of tumors. We constructed a bladder cancer-specific adenovirus carrying E1A-androgen receptor (AR) under the control of UPII promoter and prostate stem cell antigen enhancer (PSCAE), designated as Ad/PSCAE/UPII/E1A-AR, and investigated its antitumor effects in vitro and in vivo. We demonstrated that Ad/PSCAE/UPII/E1A-AR could be selectively replicated in bladder tumor cell lines (5637, BIU87, EJ and T24) when compared with control adenovirus Ad/PSCAE/UPII/Luc. However, there was no evidence of cytotoxicity for normal human bladder cell line SV-HUC-1 and hepatoma cell line SMMC7721. AR agonist R1881 could strengthen the oncolytic effect of Ad/PSCAE/UPII/E1A-AR in bladder cancer cells. In addition, we demonstrated that intratumoral injection of Ad/PSCAE/UPII/E1A-AR into established subcutaneous human EJ tumors in nude mice could significantly regress the growth of tumor and markedly prolong survival for tumor-bearing mice; on the other hand, saline-treated tumors continued to grow rapidly. Our studies indicate that Ad/PSCAE/UPII/E1A-AR could effectively treat bladder cancer in vitro and in vivo. Furthermore, our findings provide a promising therapeutic modality for the treatment of bladder cancer.

Molecular biomarkers in urothelial carcinoma of the bladder: are we there yet?

The unprecedented advances in cancer genetics and genomics are rapidly affecting the clinical management of solid tumors. Molecular diagnostics are now an integral part of routine clinical management for patients with lung, colon, and breast cancer. In sharp contrast, molecular biomarkers have been largely excluded from current management algorithms for urologic malignancies. The need for new treatment options that can improve upon the modest outcomes currently associated with muscle-invasive bladder cancer is evident, and validated prognostic molecular biomarkers that can help clinicians to identify patients in need of early, aggressive management are lacking. Robust predictive biomarkers that are able to forecast and stratify responses to emerging targeted therapies are also needed.