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Objective: To investigate the effectiveness of combination treatment of vascular targeted photodynamic therapy and anti-cytotoxic T-lymphocyte-associated antigen 4 immunotherapy in a mouse model of urothelial carcinoma., Methods: We used C57BL/6 mice injected with murine bladder 49 cell line. Mice were randomly allocated into four treatment groups: vascular targeted photodynamic therapy only, anti-cytotoxic T-lymphocyte-associated antigen 4 only, combination therapy and control. We carried out three separate experiments that used distinct cohorts of mice: tumor growth and development of lung metastases monitored with bioluminescent imaging (n = 91); survival evaluated with Kaplan-Meier curves (n = 111); and tumor cell population studied with flow cytometry (n = 20). In a fourth experiment, we re-challenged tumors in previously treated mice and compared tumor growth with that of naïve mice., Results: Combination therapy provided significant benefits over the other three treatment groups: prolonged survival (P < 0.0001), lower tumor signal (P < 0.0001) and decreased lung signal uptake (P ≤ 0.002). We also observed that mice previously treated with vascular targeted photodynamic therapy only or combination therapy did not present tumor growth after re-challenged tumors., Conclusions: Combination of vascular targeted photodynamic therapy with anti-cytotoxic T-lymphocyte-associated antigen 4 is an effective therapy in a urothelial carcinoma syngeneic mouse model. The present results suggest this therapy as a potential treatment option for both bladder and upper tract tumors in future clinical trials., (© 2019 The Japanese Urological Association.)

Purpose: WST11 vascular targeted photodynamic therapy (VTP) is a local ablation approach relying upon rapid, free radical-mediated destruction of tumor vasculature. A phase III trial showed that VTP significantly reduced disease progression when compared with active surveillance in patients with low-risk prostate cancer. The aim of this study was to identify a druggable pathway that could be combined with VTP to improve its efficacy and applicability to higher risk prostate cancer tumors. Experimental Design: Transcriptome analysis of VTP-treated tumors (LNCaP-AR xenografts) was used to identify a candidate pathway for combination therapy. The efficacy of the combination therapy was assessed in mice bearing LNCaP-AR or VCaP tumors. Results: Gene set enrichment analysis identifies the enrichment of androgen-responsive gene sets within hours after VTP treatment, suggesting that the androgen receptor (AR) may be a viable target in combination with VTP. We tested this hypothesis in mice bearing LNCaP-AR xenograft tumors by using androgen deprivation therapy (ADT), degarelix, in combination with VTP. Compared with either ADT or VTP alone, a single dose of degarelix in concert with VTP significantly inhibited tumor growth. A sharp decline in serum prostate-specific antigen (PSA) confirmed AR inhibition in this group. Tumors treated by VTP and degarelix displayed intense terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining 7 days after treatment, supporting an increased apoptotic frequency underlying the effect on tumor inhibition. Conclusions: Improvement of local tumor control following androgen deprivation combined with VTP provides the rationale and preliminary protocol parameters for clinical trials in patients presented with locally advanced prostate cancer. Clin Cancer Res; 24(10); 2408-16. ©2018 AACR ., (©2018 American Association for Cancer Research.)

Purpose: PD-1/PD-L1 pathway inhibition is effective against advanced renal cell carcinoma, although results are variable and may depend on host factors, including the tumor microenvironment. Vascular-targeted photodynamic (VTP) therapy with the photosensitizer WST11 induces a defined local immune response, and we sought to determine whether this could potentiate the local and systemic antitumor response to PD-1 pathway inhibition. Experimental Design: Using an orthotopic Renca murine model of renal cell carcinoma that develops lung metastases, we treated primary renal tumors with either VTP alone, PD-1/PD-L1 antagonistic antibodies alone, or a combination of VTP and antibodies and then examined treatment responses, including immune infiltration in primary and metastatic sites. Modulation of PD-L1 expression by VTP in human xenograft tumors was also assessed. Results: Treatment of renal tumors with VTP in combination with systemic PD-1/PD-L1 pathway inhibition, but neither treatment alone, resulted in regression of primary tumors, prevented growth of lung metastases, and prolonged survival in a preclinical mouse model. Analysis of tumor-infiltrating lymphocytes revealed that treatment effect was associated with increased CD8 + :regulatory T cell (Treg) and CD4 + FoxP3-:Treg ratios in primary renal tumors and increased T-cell infiltration in sites of lung metastasis. Furthermore, PD-L1 expression is induced following VTP treatment of human renal cell carcinoma xenografts. Conclusions: Our results demonstrate a role for local immune modulation with VTP in combination with PD-1/PD-L1 pathway inhibition for generation of potent local and systemic antitumor responses. This combined modality strategy may be an effective therapy in cancers resistant to PD-1/PD-L1 pathway inhibition alone. Clin Cancer Res; 24(3); 592-9. ©2017 AACR ., (©2017 American Association for Cancer Research.)

Purpose: Surgical management of upper tract urothelial carcinoma requires kidney and ureter removal, compromising renal function. Nonsurgical alternatives have potentially prohibitive safety concerns. We examined the feasibility and safety of ablation of the ureter and renal pelvis using endoluminal vascular targeted photodynamic therapy in a porcine model. We also report the efficacy of WST11 vascular targeted photodynamic therapy in a murine model., Materials and Methods: After receiving approval we performed a total of 28 endoluminal ablations in the ureters and renal pelvis of 18 swine. Intravenous infusion of WST11 (4 mg/kg) followed by 10-minute laser illumination was done via percutaneous access or a retrograde ureteroscopic approach. Animals were followed clinically with laboratory testing, imaging and histology, which were evaluated at several postablation time points. A murine xenograft was created with the 5637 human urothelial cell carcinoma line to determine sensitivity to this therapy., Results: At 24 hours 50 mW/cm laser fluence produced superficial necrosis of the ureter. Deeper necrosis penetrating the muscularis propria or adventitia was produced by treatment with 200 mW/cm in the ureter and the renal pelvis. At 4 weeks superficial urothelium had regenerated over the treatment site. No symptomatic obstruction, clinically relevant hydronephrosis or abnormality of laboratory testing was noted up to 4 weeks. Of the mice 80% had no evidence of tumor 19 days after WST11 vascular targeted photodynamic therapy., Conclusions: Urothelial cell carcinoma appears to be sensitive to WST11 vascular targeted photodynamic therapy. The depth of WST11 vascular targeted photodynamic therapy treatment effects can be modulated in a dose dependent manner by titrating light intensity. Moreover, when applied to the porcine upper urinary tract, this treatment modality is feasible via antegrade and retrograde access., (Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)