Transurethral Resection of Non-Muscle Invasive Bladder Tumors Combined with Fluorescence Diagnosis and Photodynamic Therapy with Chlorin e6-Type Photosensitizers

Photosensitizing effects and physicochemical properties of chlorophyll a derivatives with hydrophilic oligoethylene glycol fragments at the macrocycle periphery

In this work, screening studies of the cytotoxic effect of chlorins with fragments of di-, tri-, and pentaethylene glycol at the macrocycle periphery in relation to HeLa, A549, and HT29 cells were performed. It is shown that, despite different hydrophobicity, all the compounds studied have a comparable photodynamic effect. The conjugate of chlorin e6 with pentaethylene glycol, which has the lowest tendency to association among the studied compounds with tropism for low density lipoproteins and the best characteristics of the formation of molecular complexes with Tween 80, has a significant difference in dark and photoinduced toxicity (ratio IC50(dark)/IC50(photo) approximately 2 orders of magnitude for all cell lines), which allows to hope for a sufficiently large "therapeutic window". A study of the interaction of this compound with HeLa cells shows that the substance penetrates the cell and, after red light irradiation induces ROS appearance inside the cell, associated, apparently, with the photogeneration of singlet oxygen. These data indicate that photoinduced toxic effects are caused by damage to intracellular structures as a result of oxidative stress. Programmed type of cell death characterized with caspase-3 induction is prevailing. So, the conjugate of chlorin e6 with pentaethylene glycol is a promising antitumor PS that can be successfully solubilized with Tween 80, which makes it suitable for further in vivo studies.

Photo- and X-ray Induced Cytotoxicity of CeF3-YF3-TbF3 Nanoparticle-Polyvinylpyrrolidone-"Radachlorin" Composites for Combined Photodynamic Therapy

The Ce0.5Y0.35Tb0.15F3 nanoparticles with a CeF3 hexagonal structure were synthesized using the co-precipitation technique. The average nanoparticle diameter was 14 ± 1 nm. The luminescence decay curves of the Ce0.5Y0.35Tb0.15F3 nanoparticles (λem = 541 nm, 5D4-7F5 transition of Tb3+) conjugated with Radachlorin using polyvinylpyrrolidone coating as well as without Radachlorin were detected. Efficient nonradiative energy transfer from Tb3+ to the Radachlorin was demonstrated. The maximum energy transfer coefficients for the nanoparticles conjugated with Radachlorin via polyvinylpyrrolidone and without the coating were 82% and 55%, respectively. The average distance between the nanoparticle surface and Radachlorin was R0 = 4.5 nm. The best results for X-ray-induced cytotoxicity were observed for the NP-PVP-Rch sample at the lowest Rch concentration. In particular, after X-ray irradiation, the survival of A549 human lung carcinoma cells decreased by ~12%.

Recent Studies in Photodynamic Therapy for Cancer Treatment: From Basic Research to Clinical Trials

Photodynamic therapy (PDT) is an emerging and less invasive treatment modality for various types of cancer. This review provides an overview of recent trends in PDT research, ranging from basic research to ongoing clinical trials, focusing on different cancer types. Lung cancer, head and neck cancer, non-melanoma skin cancer, prostate cancer, and breast cancer are discussed in this context. In lung cancer, porfimer sodium, chlorin e6, and verteporfin have shown promising results in preclinical studies and clinical trials. For head and neck cancer, PDT has demonstrated effectiveness as an adjuvant treatment after surgery. PDT with temoporfin, redaporfin, photochlor, and IR700 shows potential in early stage larynx cancer and recurrent head and neck carcinoma. Non-melanoma skin cancer has been effectively treated with PDT using methyl aminolevulinate and 5-aminolevulinic acid. In prostate cancer and breast cancer, PDT research is focused on developing targeted photosensitizers to improve tumor-specific uptake and treatment response. In conclusion, PDT continues to evolve as a promising cancer treatment strategy, with ongoing research spanning from fundamental investigations to clinical trials, exploring various photosensitizers and treatment combinations. This review sheds light on the recent advancements in PDT for cancer therapy and highlights its potential for personalized and targeted treatments.

Photodynamic Therapy for Bladder Cancers, A Focused Review†

Bladder cancer is the first cancer for which PDT was clinically approved in 1993. Unfortunately, it was unsuccessful due to side effects like bladder contraction. Here, we summarized the recent progress of PDT for bladder cancers, focusing on photosensitizers and formulations. General strategies to minimize side effects are intravesical administration of photosensitizers, use of targeting strategies for photosensitizers and better control of light. Non-muscle invasive bladder cancers are more suitable for PDT than muscle invasive and metastatic bladder cancers. In 2010, the FDA approved blue light cystoscopy, using PpIX fluorescence, for photodynamic diagnosis of non-muscle invasive bladder cancer. PpIX produced from HAL was also used in PDT but was not successful due to low therapeutic efficacy. To enhance the efficacy of PpIX-PDT, we have been working on combining it with singlet oxygen-activatable prodrugs. The use of these prodrugs increases the therapeutic efficacy of the PpIX-PDT. It also improves tumor selectivity of the prodrugs due to the preferential formation of PpIX in cancer cells resulting in decreased off-target toxicity. Future challenges include improving prodrugs and light delivery across the bladder barrier to deeper tumor tissue and generating an effective therapeutic response in an In vivo setting without causing collateral damage to bladder function.

Precise diagnosis and treatment of non-muscle invasive bladder cancer - A clinical perspective

According to the guidelines, transurethral resection of bladder tumor (TURBT) followed by intravesical therapy remains the standard strategy for the management of non-muscle invasive bladder cancer (NMIBC). However, even if patients receive standard strategy, the risk of postoperative recurrence and progression is high. From the clinical perspective, the standard strategy needs to be optimized and improved. Compared to conventional TURBT, the technique of en bloc resection of bladder tumor (ERBT) removes the tumor tissue in one piece, thus following the principles of cancer surgery. Meanwhile, the integrity and spatial orientation of tumor tissue is protected during the operation, which is helpful for pathologists to make accurate histopathological analysis. Then, urologists can make a postoperative individualized treatment plan based on the patient's clinical characteristics and histopathological results. To date, there is no strong evidence that NMIBC patients treated with ERBT achieve better oncological prognosis, which indicates that ERBT alone does not yet improve patient outcomes. With the development of enhanced imaging technology and proteogenomics technology, en bloc resection combined with these technologies will make it possible to achieve precise diagnosis and treatment of bladder cancer. In this review, the authors analyze the current existing shortcomings of en bloc resection and points out its future direction, in order to promote continuous optimization of the management strategy of bladder cancer.

Monocationic Chlorin as a Promising Photosensitizer for Antitumor and Antimicrobial Photodynamic Therapy

Cancer is one of the leading causes of death worldwide. Despite substantial progress in the understanding of tumor biology, and the appearance of new generations of targeted drugs and treatment techniques, the success achieved in this battle, with some notable exceptions, is still only moderate. Photodynamic therapy (PDT) is a successful but still underestimated therapeutic modality for treating many superficial cancers. In this paper, we focus on the extensive investigation of the monocationic chlorin photosensitizer (PS), considered here as a new photosensitizing agent for both antitumor and antimicrobial PDT. This monocationic chlorin PS (McChl) obtained from methylpheophorbide a (MPh) via a two-step procedure is well soluble in water in the physiological temperature range and forms stable complexes with passive carriers. McChl generates singlet oxygen with a good quantum yield in a lipid-like environment and binds mainly to low- and high-density lipoproteins in a vascular system. A comparison of the photodynamic activity of this agent with the activity of the well-established photosensitizer chlorin e₆ (Chl e₆) clearly indicates that McChl provides a much more efficient photoinactivation of malignant and microbial cells. The pilot PDT treatment of M1 sarcoma-bearing rats with this PS demonstrates its good potential for further preclinical investigations.

Advances in Diagnosis and Therapy for Bladder Cancer

Simple Summary

The clinical management of bladder cancer has been developing in the past decade, including diagnostic tools and treatment options. Both monotherapy and combination therapy have been undoubtedly upgraded. Multiple diagnostic techniques and therapeutic strategies have been developed to meet the urgent clinical needs, resulting in the emergence of various explorations for cancer diagnosis and therapy. In this review, we mainly focus on the advances in the diagnosis and treatment of bladder cancer.

Abstract

Bladder cancer (BCa) is one of the most common and expensive urinary system malignancies for its high recurrence and progression rate. In recent years, immense amounts of studies have been carried out to bring a more comprehensive cognition and numerous promising clinic approaches for BCa therapy. The development of innovative enhanced cystoscopy techniques (optical techniques, imaging systems) and tumor biomarkers-based non-invasive urine screening (DNA methylation-based urine test) would dramatically improve the accuracy of tumor detection, reducing the risk of recurrence and progression of BCa. Moreover, intravesical instillation and systemic therapeutic strategies (cocktail therapy, immunotherapy, vaccine therapy, targeted therapy) also provide plentiful measures to break the predicament of BCa. Several exploratory clinical studies, including novel surgical approaches, pharmaceutical compositions, and bladder preservation techniques, emerged continually, which are supposed to be promising candidates for BCa clinical treatment. Here, recent advances and prospects of diagnosis, intravesical or systemic treatment, and novel drug delivery systems for BCa therapy are reviewed in this paper.

Solvation, Cancer Cell Photoinactivation and the Interaction of Chlorin Photosensitizers with a Potential Passive Carrier Non-Ionic Surfactant Tween 80

Cancer and drug-resistant superinfections are common and serious problems afflicting millions worldwide. Photodynamic therapy (PDT) is a successful and clinically approved modality used for the management of many neoplastic and nonmalignant diseases. The combination of the light-activated molecules, so-called photosensitizers (PSs), with an appropriate carrier, is proved to enhance PDT efficacy both in vitro and in vivo. In this paper, we focus on the solvation of several potential chlorin PSs in the 1-octanol/phosphate saline buffer biphasic system, their interaction with non-ionic surfactant Tween 80 and photoinactivation of cancer cells. The chlorin conjugates containing d-galactose and l-arginine fragments are found to have a much stronger affinity towards a lipid-like environment compared to ionic chlorins and form molecular complexes with Tween 80 micelles in water with two modes of binding. The charged macrocyclic PSs are located in the periphery of surfactant micelles near hydrophilic head groups, whereas the d-galactose and l-arginine conjugates are deeper incorporated into the micelle structure occupying positions around the first carbon atoms of the hydrophobic surfactant residue. Our results indicate that both PSs have a pronounced affinity toward the lipid-like environment, leading to their preferential binding to low-density lipoproteins. This and the conjugation of chlorin e₆ with the tumor-targeting molecules are found to enhance their accumulation in cancer cells and PDT efficacy.