scholarly journals In vivo photobleaching kinetics and epithelial biodistribution of hexylaminolevulinate-induced protoporphyrin IX in rat bladder cancer

2021 ◽  
Vol 15 (1) ◽  
pp. 2-10
Author(s):  
Sami El Khatib
2019 ◽  
Vol 23 (07n08) ◽  
pp. 813-820
Author(s):  
Odrun A. Gederaas ◽  
Harald Husebye ◽  
Anders Johnsson ◽  
Susan Callaghan ◽  
Anders Brunsvik

Aminolevulinic acid and hexyl-aminolevulinate serve as biological precursors to produce photosensitive porphyrins in cells via the heme biosynthetic pathway. This pathway is integral to porphyrin-based photodynamic diagnosis and therapy. By adding exogenous hexyl-aminolevulinate to rat bladder cancer cells (AY27, in vitro) and an animal bladder cancer model (in vivo), fluorescent endogenous porphyrin production was stimulated. Lipophilic protoporphyrin IX was identified as the dominant species by reverse high-pressure liquid chromatography. Subcellular porphyrin localization in the AY27 cells was evaluated by confocal laser scanning microscopy and showed almost quantitative bleaching after 20 s. From this study, we ascertained that the protocol described herein is suitable for hexyl-aminolevulinate-mediated photodynamic therapy and diagnosis when protoporphyrin IX is the active agent.


2020 ◽  
Vol 6 (3) ◽  
pp. 285-294 ◽  
Author(s):  
Sabine Meessen ◽  
Jan Rother ◽  
Xi Zheng ◽  
Markus Eckstein ◽  
Maximilian C. Kriegmair ◽  
...  

BACKGROUND: Emerging imaging technologies such as real-time multispectral imaging (rMSI) hold great potential for simultaneous visualization of multiple target structures using fluorophores on various tumours including bladder cancer (BC). These technologies, however, require a multi-step preclinical evaluation process, including mouse models. OBJECTIVE: To demonstrate the suitability of the new rMSI technology for the detection of premalignant lesions and malignant BC in a preclinical mouse model using contrast agents. METHODS: Tumours were induced by N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN), which is known to induce BC in rodent models. In total, 30 mice (C57BL/6) were fed with 0.1% BBN ad libitum in drinking water for up to 5 months. Bladders were excised at 3 (n = 6) and 5 months (n = 24) of treatment and incubated ex vivo with Hexaminolevulinat (HAL, Hexvix®), CD47-FITC, CD90.2-FITC or a combination of CD90.2-FITC/CD47-FITC and HAL. The bladders were analyzed by an endoscopic rMSI prototype system equipped with a spectral filter (Chroma), a 4 mm endoscope (Karl Storz) with 30° optic, a LED light source and a PC with a microcontroller board. RESULTS: 5-month treatment of mice with 0.1% BBN led to the formation of squamous carcinoma (46%, n = 11) while urothelial carcinoma was observed only in one mouse (4%, n = 1). Carcinoma in situ (CIS) was detectable in twelve out of twenty-four mice (50%, n = 12) treated for 5 month and in three out of six mice (50%, n = 3) treated for 3 months.The metabolite of HAL, protoporphyrin IX (PpIX), could be reliably and specifically detected in all of mouse bladder tumours and CIS. However, detection of the CD90.2 surface marker was less reliable, potentially due to species- or tumour-subtype specificity. CONCLUSIONS: This model offers the potential for preclinical imaging studies with combined fluorescence targets, e.g. HAL, in combination with BC-specific antibodies.


2021 ◽  
pp. 302-309
Author(s):  
Odrun A. Gederaas ◽  
Harald Husebye ◽  
Anders Johnsson ◽  
Susan Callaghan ◽  
Anders Brunsvik

2020 ◽  
pp. 1-12
Author(s):  
Maroeska J. Burggraaf ◽  
Lisette Waanders ◽  
Mariska Verlaan ◽  
Janneke Maaskant ◽  
Diane Houben ◽  
...  

BACKGROUND: Bladder cancer is the ninth most common cancer in men. 70% of these tumors are classified as non-muscle invasive bladder cancer and those patients receive 6 intravesical instillations with Mycobacterium bovis BCG after transurethral resection. However, 30% of patients show recurrences after treatment and experience severe side effects that often lead to therapy discontinuation. Recently, another vaccine strain, Salmonella enterica typhi Ty21a, demonstrated promising antitumor activity in vivo. Here we focus on increasing bacterial retention in the bladder in order to reduce the number of instillations required and improve antitumor activity. OBJECTIVE: To increase the binding of Ty21a to the bladder wall by surface labeling of the bacteria with adhesion protein FimH and to study its effect in a bladder cancer mouse model. METHODS: Binding of Ty21a with surface-labeled FimH to the bladder wall was analyzed in vitro and in vivo. The antitumor effect of a single instillation of Ty21a+FimH in treatment was determined in a survival experiment. RESULTS: FimH-labeled Ty21a showed significant (p <  0.0001) improved binding to mouse and human cell lines in vitro. Furthermore, FimH labeled bacteria showed ∼5x more binding to the bladder than controls in vivo. Enhanced binding to the bladder via FimH labeling induced a modest improvement in median but not in overall mice survival. CONCLUSIONS: FimH labeling of Ty21a significantly improved binding to bladder tumor cells in vitro and the bladder wall in vivo. The improved binding leads to a modest increase in median survival in a single bladder cancer mouse study.


2021 ◽  
pp. 019262332110274
Author(s):  
Ayumi Eguchi ◽  
Satoki Fukunaga ◽  
Keiko Ogata ◽  
Masahiko Kushida ◽  
Hiroyuki Asano ◽  
...  

Porphyrinogenic compounds are known to induce porphyria-mediated hepatocellular injury and subsequent regenerative proliferation in rodents, ultimately leading to hepatocellular tumor induction. However, an appropriate in vivo experimental model to evaluate an effect of porphyrinogenic compounds on human liver has not been fully established. Recently, the chimeric mouse with humanized liver (PXB mice) became widely used as a humanized model in which human hepatocytes are transplanted. In the present study, we examined the utility of PXB mice as an in vivo experimental model to evaluate the key events of the porphyria-mediated cytotoxicity mode of action (MOA) in humans. The treatment of PXB mice with 5-aminolevulinic acid, a representative porphyrinogenic compound, for 28 days caused protoporphyrin IX accumulation, followed by hepatocyte necrosis, increased mitosis, and an increase in replicative DNA synthesis in human hepatocytes, indicative of cellular injury and regenerative proliferation, similar to findings in patients with porphyria or experimental porphyria models and corresponding to the key events of the MOA for porphyria-mediated hepatocellular carcinogenesis. We conclude that the PXB mouse is a useful model to evaluate the key events of the porphyria-mediated cytotoxicity MOA in humans and suggest the utility of PXB mice for clarifying the human relevancy of findings in mice.


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