Synergistic effect of photodynamic therapy and cisplatin: a novel approach for cervical cancer

The Effects of Photodynamic Therapy with Low-Level Diode Laser Compared with Doxorubicin on HT-29 Colorectal Adenocarcinoma Cells Viability

Background and Objective: Colorectal adenocarcinoma is considered one of the major causes of cancer-related lethality among other type of malignancies. Given the several limitations and adverse outcomes of conventional therapeutic regimens against colorectal cancer, the focus of many investigations has been attributed to the introduction of a novel combined regimen with harmless agents. The purpose of the present study was to investigate the effect of combined doxorubicin (DOX) treatment and photodynamic therapy (PDT) on colorectal adenocarcinoma cells. Material and Methods: HT-29 cells were exposed to different concentrations of DOX, low-level (630 nm) diode laser, and methylene blue (MB) as a photosensitizer substrate separately and a combination of them. The cytotoxic effect of the DOX, laser, MB, and their combination and the IC50 value for each treatment group were calculated by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT). The malondialdehyde (MDA) content as a biomarker of the lipid peroxidation process and liberated lactate dehydrogenase (LDH) enzyme into supernatant was determined. Results: The results of our study evidenced that a combination of photodynamic light (laser plus MB) and DOX caused a significant reduction in the percentage of HT-29 viable cells compared with control and other treatment groups. In addition, this mentioned combination led to a considerable decrease in IC50 of DOX. Increased cell membrane lipid peroxidation and cell destruction processes in the combination therapy group were proven through significant elevation of MDA content and LDH activity in the medium, respectively. Conclusion: The findings of the present study suggested that DOX combined with PDT had a better therapeutic impact on HT-29 colorectal adenocarcinoma cells. Hence, the simultaneous application of PDT along with antineoplastic drugs improves the chemosensitivity of cancerous cells via the disruption of their membrane and triggering death processes that lead to the decrease of chemotherapeutic agents required doses and undesirable effects.

Preparation of Composite Hydrogels Based on Cysteine-Silver Sol and Methylene Blue as Promising Systems for Anticancer Photodynamic Therapy

In this study, a novel supramolecular composite, "photogels", was synthesized by mixing of cysteine-silver sol (CSS) and methylene blue (MB). A complex of modern physico-chemical methods of analysis such as viscosimetry, UV spectroscopy, dynamic and electrophoretic light scattering, scanning electron microscopy and energy-dispersive X-ray spectroscopy showed that MB molecules are uniformly localized mainly in the space between fibers of the gel-network formed by CSS particles. Molecules of the dye also bind with the surface of CSS particles by non-covalent interactions. This fact is reflected in the appearance of a synergistic anticancer effect of gels against human squamous cell carcinoma even in the absence of light irradiation. A mild toxic influence of hydrogels was observed in normal keratinocyte cells. Photodynamic exposure significantly increased gel activity, and there remained a synergistic effect. The study of free-radical oxidation in cells has shown that gels are not only capable of generating reactive oxygen species, but also have other targets of action. Flow cytometric analysis allowed us to find out that obtained hydrogels caused cell cycle arrest both without irradiation and with light exposure. The obtained gels are of considerable interest both from the point of view of academics and applied science, for example, in the photodynamic therapy of superficial neoplasms.

Recent advances in photodynamic therapy combined with chemotherapy for cervical cancer: a systematic review

INTRODUCTION

Despite the evidence that photodynamic therapy (PDT) associated with chemotherapy presents great potential to overcome the limitations of monotherapy, little is known about the current status of this combination against cervical cancer. This systematic review aimed to address the currently available advances in combining PDT and chemotherapy in different research models and clinical trials of cervical cancer.

METHODS

We conducted a systematic review based on PRISMA Statement and Open Science Framework review protocol using PubMed, Web of Science, Embase, Scopus, LILACS, and Cochrane databases. We selected original articles focusing on 'Uterine Cervical Neoplasms' and 'Photochemotherapy and Chemotherapy' published in the last 10 years. The risk of bias in the studies was assessed using the CONSORT and SYRCLE tools.

RESULTS

Twenty-three original articles were included, focusing on HeLa cells, derived from endocervical adenocarcinoma and on combinations of several chemotherapeutics. Most of the combinations used modern drug delivery systems for improved simultaneous delivery and presented promising results with increased cytotoxicity compared to monotherapy.

CONCLUSION

Despite the scarcity of animal studies and the absence of clinical studies, the combination of chemotherapy with PDT presents a potential option for cervical cancer therapy requiring additional studies.

OSF REGISTRATION

https://doi.org/10.17605/OSF.IO/WPHN5 [Figure: see text].

The diverse effects of cisplatin on tumor microenvironment: Insights and challenges for the delivery of cisplatin by nanoparticles

Cisplatin is a well-known platinum-based chemotherapy medication that is widely utilized for some malignancies. Despite the direct cytotoxic consequences of cisplatin on tumor cells, studies in the recent decade have revealed that cisplatin can also affect different cells and their secretions in the tumor microenvironment (TME). Cisplatin has complex impacts on the TME, which may contribute to its anti-tumor activity or drug resistance mechanisms. These regulatory effects of cisplatin play a paramount function in tumor growth, invasion, and metastasis. This paper aims to review the diverse impacts of cisplatin and nanoparticles loaded with cisplatin on cancer cells and also non-cancerous cells in TME. The impacts of cisplatin on immune cells, tumor stroma, cancer cells, and also hypoxia will be discussed in the current review. Furthermore, we emphasize the challenges and prospects of using cisplatin in combination with other adjuvants and therapeutic modalities that target TME. We also discuss the potential synergistic effects of cisplatin with immune checkpoint inhibitors (ICIs) and other agents with anticancer potentials such as polyphenols and photosensitizers. Furthermore, the potential of nanoparticles for targeting TME and better delivery of cisplatin into tumors will be discussed.

Study on the effect of 5-aminolevulinic acid-mediated photodynamic therapy combined with cisplatin on human ovarian cancer OVCAR-3 ​cells

PURPOSE

This article explores the effect of 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) combined with cisplatin (CDDP) on the apoptosis of human ovarian cancer cells and the mechanism of action of the combination therapy.

MATERIALS AND METHODS

Human ovarian cancer OVCAR-3 ​cells were cultured in vitro and divided into 5-ALA/PDT group, CDDP group and combined treatment group (5-ALA/PDT combined with different concentrations of CDDP). After administration of the corresponding drugs, a CCK-8 assay was used to detect the inhibition rate of cell proliferation. After Rhodamine 123 staining, mitochondrial membrane potential changes were observed under fluorescence microscopy. The apoptosis rate and reactive oxygen species (ROS) content were detected by flow cytometry. Western blotting was used to detect protein expression.

RESULTS

The CCK-8 assay showed that CDDP in combination with 5-ALA/PDT significantly enhanced cytotoxicity compared to treatment with CDDP alone and that low doses of CDDP were sufficient to induce these combination effects. The mitochondrial membrane potential in each combination treatment group gradually decreased with increasing CDDP concentration, while the apoptosis rate and reactive oxygen species (ROS) content detected by flow cytometry gradually increased. Western blotting assay showed that the expression of bax, cleaved caspase-9, cleaved caspase-3, and cleaved PARP was increased, while the expression of bcl-2, caspase-9, caspase-3, and PARP was decreased, and the differences were statistically significant (P ​< ​0.05).

CONCLUSIONS

In summary, 5-ALA/PDT combined with CDDP can effectively inhibit cell proliferation and promote apoptosis, and this combination may induce apoptosis by activating the mitochondrial pathway.

Monoolein-based nanodispersions for cutaneous co-delivery of methylene blue and metformin: Thermal and structural characterization and effects on the cutaneous barrier, skin penetration and cytotoxicity

This study evaluated the potential of monoolein (MO)-based nanodispersions to promote the cutaneous co-delivery of metformin (MET) and methylene blue (MB) for the treatment of non-melanoma skin cancer. MO-based nanodispersions were obtained using Kolliphor® P407 (KP) and/or sodium cholate (CH), and characterized concerning the structure, thermal stability, ability to disrupt the skin barrier, cutaneous permeation and retention of MB and MET. Additionally, the cytotoxic effect of MO nanodispersions-mediated combination therapy using MET and MB in A431 cells was evaluated. The nanodispersions exhibited nanometric size (<200 nm) and thermal and physical stability. Small angle X-ray scattering studies revealed multiple structures depending on composition. They were able to interact with stratum corneum lipid structure, increasing its fluidity. The effect of MO-nanodispersions on topical/transdermal delivery of MB and MET was composition-dependent. Nanodispersions with low MO content (5 %) and stabilized with KP and CH (0.05-0.10 %) were the most promising, enhancing the cutaneous delivery of MB and MET by 1.9 to 2.2-fold and 1.4 to 1.7-fold, respectively, compared to control. Cytotoxic studies revealed that the most promising MO nanodispersion-mediated combination therapy using MET and MB (1:1) reduced the IC₅₀ by 24-fold, compared to MB solution, and a further reduction (1.5-fold) was observed by MB photoactivation.

Cellular landscaping of cisplatin resistance in cervical cancer

Cervical cancer (CC) caused by human papillomavirus (HPV) is one of the largest causes of malignancies in women worldwide. Cisplatin is one of the widely used drugs for the treatment of CC is rendered ineffective owing to drug resistance. This review highlights the cause of resistance and the mechanism of cisplatin resistance cells in CC to develop therapeutic ventures and strategies that could be utilized to overcome the aforementioned issue. These strategies would include the application of nanocarries, miRNA, CRIPSR/Cas system, and chemotherapeutics in synergy with cisplatin to not only overcome the issues of drug resistance but also enhance its anti-cancer efficiency. Moreover, we have also discussed the signaling network of cisplatin resistance cells in CC that would provide insights to develop therapeutic target sites and inhibitors. Furthermore, we have discussed the role of CC metabolism on cisplatin resistance cells and the physical and biological factors affecting the tumor microenvironments.

The Rationale for "Laser-Induced Thermal Therapy (LITT) and Intratumoral Cisplatin" Approach for Cancer Treatment

Cisplatin is one of the most widely used anticancer drugs in the treatment of various types of solid human cancers, as well as germ cell tumors, sarcomas, and lymphomas. Strong evidence from research has demonstrated higher efficacy of a combination of cisplatin and derivatives, together with hyperthermia and light, in overcoming drug resistance and improving tumoricidal efficacy. It is well known that the antioncogenic potential of CDDP is markedly enhanced by hyperthermia compared to drug treatment alone. However, more recently, accelerators of high energy particles, such as synchrotrons, have been used to produce powerful and monochromatizable radiation to induce an Auger electron cascade in cis-platinum molecules. This is the concept that makes photoactivation of cis-platinum theoretically possible. Both heat and light increase cisplatin anticancer activity via multiple mechanisms, generating DNA lesions by interacting with purine bases in DNA followed by activation of several signal transduction pathways which finally lead to apoptosis. For the past twenty-seven years, our group has developed infrared photo-thermal activation of cisplatin for cancer treatment from bench to bedside. The future development of photoactivatable prodrugs of platinum-based agents injected intratumorally will increase selectivity, lower toxicity and increase efficacy of this important class of antitumor drugs, particularly when treating tumors accessible to laser-based fiber-optic devices, as in head and neck cancer. In this article, the mechanistic rationale of combined intratumor injections of cisplatin and laser-induced thermal therapy (CDDP-LITT) and the clinical application of such minimally invasive treatment for cancer are reviewed.

In Vitro Therapeutic Attributes of Luminescent Hydroxyapatite Nanoparticles in Codelivery Module

Imminent prospects of clinical importance have been accomplished through divergent treatment modalities implemented using nanoscale platforms. In the present study, hydroxyapatite nanoparticles doped with copper nanoclusters (HAPs) were explored for codelivery of a hydrophobic drug, namely, norfloxacin (NX), and a hydrophilic photosensitizer, such as methylene blue (MB). NX and MB were successfully homed into HAPs (MB-NX-HAPs), which further exhibited a pH-dependent release of both. With the objective of attaining an enhanced effect, MB-NX-HAPs were evaluated for combination therapy, involving chemotherapy and photodynamic therapy (PDT) with irradiation at 640 nm. The combinatorial therapy approach was initially applied for antibacterial therapy, which suggested a considerable reduction in bacterial growth of Gram-negative strain Pseudomonas aeruginosa MTCC 2488. Thereafter, the antiproliferative study performed in cancer cell lines (HeLa and MCF-7) revealed the efficiency of MB-NX-HAPs in bestowing a combinatorial effect through chemotherapy and PDT (irradiation at 640 nm). The combined effect exerted through MB-NX-HAPs subsequently induced reactive oxygen species (ROS) generation, cell cycle alteration, and apoptosis activation in cancer cells. The biocompatible nature of MB-NX-HAPs was appreciably shown through their minimal effect on the normal cell line (HEK-293). Additionally, HAPs through luminescence of copper nanoclusters were suggested to aid in bioimaging of cancer cell lines.

CD44 Receptor-Mediated/Reactive Oxygen Species-Sensitive Delivery of Nanophotosensitizers against Cervical Cancer Cells

Stimulus-sensitive, nanomedicine-based photosensitizer delivery has an opportunity to target tumor tissues since oxidative stress and the expression of molecular proteins, such as CD44 receptors, are elevated in the tumor microenvironment. The aim of this study is to investigate the CD44 receptor- and reactive oxygen species (ROS)-sensitive delivery of nanophotosensitizers of chlorin e6 (Ce6)-conjugated hyaluronic acid (HA) against HeLa human cervical cancer cells. For the synthesis of nanophotosensitizers, thioketal diamine was conjugated with the carboxyl group in HA and then the amine end group of HA-thioketal amine conjugates was conjugated again with Ce6 (Abbreviated as HAthCe6). The HAthCe6 nanophotosensitizers were of small diameter, with sizes less than 200. Their morphology was round-shaped in the observations using a transmission electron microscope (TEM). The HAthCe6 nanophotosensitizers responded to oxidative stress-induced changes in size distribution when H₂O₂ was added to the nanophotosensitizer aqueous solution, i.e., their monomodal distribution pattern at 0 mM H₂O₂ was changed to dual- and/or multi-modal distribution patterns at higher concentrations of H₂O₂. Furthermore, the oxidative stress induced by the H₂O₂ addition contributed to the disintegration of HAthCe6 nanophotosensitizers in morphology, and this phenomenon accelerated the release rate of Ce6 from nanophotosensitizers. In a cell culture study using HeLa cells, nanophotosensitizers increased Ce6 uptake ratio, ROS generation and PDT efficacy compared to free Ce6. Since HA specifically bonds with the CD44 receptor of cancer cells, the pretreatment of free HA against HeLa cells decreased the Ce6 uptake ratio, ROS generation and PDT efficacy of HAthCe6 nanophotosensitizers. These results indicated that intracellular delivery of HAthCe6 nanophotosensitizers can be controlled by the CD44 receptor-mediated pathway. Furthermore, these phenomena induced CD44 receptor-controllable ROS generation and PDT efficacy by HAthCe6 nanophotosensitizers. During in vivo tumor imaging using HeLa cells, nanophotosensitizer administration showed that the fluorescence intensity of tumor tissues was relatively higher than that of other organs. When free HA was pretreated, the fluorescence intensity of tumor tissue was relatively lower than those of other organs, indicating that HAthCe6 nanophotosensitizers have CD44 receptor sensitivity and that they can be delivered by receptor-specific manner. We suggest that HAthCe6 nanophotosensitizers are promising candidates for PDT in cervical cancer.

Targeted drug delivery in cervical cancer: Current perspectives

Cervical cancer is preventable yet one of the most prevalent cancers among women around the globe. Though regular screening has resulted in the decline in incidence, the disease claims a high number of lives every year, especially in the developing countries. Owing to rather aggressive and non-specific nature of the conventional chemotherapeutics, there is a growing need for newer treatment modalities. The advent of nanotechnology has assisted in this through the use of nanocarriers for targeted drug delivery. A number of nanocarriers are continuously being developed and studied for their application in drug delivery. The present review summarises the different drug delivery approaches and nanocarriers that can be useful, their advantages and limitation.

Evaluation of Biological Activity of Different Wavelengths of Low-Level Laser Therapy on the Cancer Prostate Cell Line Compared With Cisplatin

Introduction: Cancer is one of the most important problems in the world. Low-level laser therapy (LLLT) has been emerged as a new approach, having both stimulation and inhibition effects on cellular function. The goal of this study was to analyze and compare the different concentrations of cisplatin and wavelengths of laser therapy on the LnCap cell lines. Methods: LnCap cells were cultured and treated with different concentrations of cisplatin (0.1, 0.4, 0.8, 1.2 and 2 µg/mL for 24 hours) and wavelengths of laser therapy (610, 630 and 810 nm) (0.45 J/cm²) separately. The viability of cells was examined by MTT assay and IC50 was also calculated. Furthermore, a combination of cisplatin IC50 (24 hours) and different wavelengths of the laser was examined. Results: The results of this study showed that 2 µg/mL of cisplatin has the most significant reduction effect on the cell viability of the LnCap cell line. Cisplatin decreased the viability of cells in a dose-dependent manner. Moreover, IC50 of cisplatin was 1.24 µg/mL. On the other hand, LLLT with wavelengths of 610, 630 and 810 nm did not show notable biological effects on cell viability. Conclusion: As known, cisplatin has the capability to reduce the viability of LnCap cell lines. However, LLLT cannot be a remarkable option for the treatment of prostate cancer. Therefore, although laser therapy showed praiseful therapeutic activity against some cancer cell lines, in this study the results indicated that defined laser wavelengths had no inhibitory effects against the prostate cancer cell line.

Pheophorbide co-encapsulated with Cisplatin in folate-decorated PLGA nanoparticles to treat nasopharyngeal carcinoma: Combination of chemotherapy and photodynamic therapy

The adverse effect and drug resistance of Cisplatin (CDDP) could be potential reduced by delivering in targeted nanoparticles and by combining with adjuvant therapy such as photodynamic therapy. In this study, F/CDPR-NP was formulated and characterized for all the physicochemical, biological and in vivo analysis. The results obtained from various in vitro and biological studies showed that encapsulation of CDDP and PBR in PLGA nanoparticles results in controlled release of encapsulated drugs and exhibited significantly low cell viability in CNE-1 and HNE-1 cancer cells. F/CDPR-NP significantly prolonged the blood circulation of the encapsulated drugs. The AUC of CDDP from F/CDPR-NP (4-fold) was significantly higher compared to that of free CDDP and similarly significantly higher t1/2 for CDDP from F/CDPR-NP was observed. F/CDPR-NP in the presence of laser irradiation showed significant reduction in the tumor burden with low tumor cell proliferations compared to either CDPR-NP or free CDDP indicating the potential of targeted nanoparticles and photodynamic therapy. Overall, combination of treatment modalities and active targeting approach paved way for the higher antitumor activity in nasopharyngeal carcinoma model. The positive results from this study will show new horizon for the treatment of other cancer models.

In Vitro Anticancer Activity of Nanoformulated Mono- and Di-nuclear Pt Compounds

Nanoformulations of mononuclear Pt complexes cis-PtCl₂ (PPh₃ )₂ (1), [Pt(PPh₃ )₂ (L-Cys)] ⋅ H₂ O (3, L-Cys=L-cysteinate), trans-PtCl₂ (PPh₂ PhNMe₂ )₂ (4; PPh₂ PhNMe₂ =4-(dimethylamine)triphenylphosphine), trans-PtI₂ (PPh₂ PhNMe₂ )₂ (5) and dinuclear Pt cluster Pt₂ (μ-S)₂ (PPh₃ )₄ (2) have comparable cytotoxicity to cisplatin against murine melanoma cell line B16F10. Masking of these discrete molecular entities within the hydrophobic core of Pluronic® F-127 significantly boosted their solubility and stability, ensuring efficient cellular uptake, giving in vitro IC₅₀ values in the range of 0.87-11.23 μM. These results highlight the potential therapeutic value of Pt complexes featuring stable Pt-P bonds in nanocomposite formulations with biocompatible amphiphilic polymers.

Combination of cisplatin treatment and photodynamic therapy attenuates cisplatin-induced cell toxicity in A2780 and A2780-CP cervical cancer cell lines

Cervical cancer is recognized as a serious worldwide health problem. Despite various achievements for cervical cancer treatment, there are still shortcomings that lead to severe side effects. Combination therapy is fast becoming a key and promising treatment strategy, diminishing chemotherapy-mediated side effects. The objective of this study was to determine the effect of combined cisplatin treatment and photodynamic therapy (PDT) on the cervical cancer recovery. In this study, A2780 and A2780-CP cell lines were cultured in the Dulbecco's modified eagle medium (DMEM) enriched with 10% FBS and 1% antibiotic. Both cell lines were treated with cisplatin, photodynamic light (laser with methylene blue as a photosensitizer agent), and the combination of cisplatin treatment and PDT. Half maximum inhibitory concentration (IC50) was calculated for each treatment by the use of tetrazolium salt assay. Both cell lines were examined for cell membrane lipid peroxidation rate. Our findings showed that combination of cisplatin treatment and photodynamic therapy leads to two-fold decreased cisplatin IC50. Results showed that cisplatin and photodynamic light combination could effectively reduce A2780 and A2780-CP cell viability (p-value < 0.0001). Moreover, combined cisplatin and photodynamic therapy results revealed significantly increased cancer cell membrane destruction through increased lipid peroxidation, resulting in surged MDA content. Our conclusion is that combination of cisplatin and photodynamic therapy can be used as an effective and convenient treatment strategy without considerable side effects.

Berberine-photodynamic therapy sensitizes melanoma cells to cisplatin-induced apoptosis through ROS-mediated P38 MAPK pathways

The clinical use of cisplatin are limited due to its drug resistance. Thus, it is urgent to find effective combination therapy that sensitizes tumor cells to this drug. The combined chemo-photodynamic therapy could increase anti-tumor efficacy while also reduce the side effects of cisplatin. Berberine is an isoquinoline alkaloid, which has been reported to show high photosensitizing activity. In this study, we have examined the effect of a combination of cisplatin and berberine-PDT in cisplatin-resistant melanoma cells. The cytotoxic effects of berberine-PDT alone or in combination with cisplatin were tested by MTT assays. We then examined the subcellular localization of berberine with confocal fluorescence microscopy. The percentage of apoptotic cells, the mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS) generation assessed using flow cytometry analysis. Western blotting used in this study to determine the expression levels of MAPK signaling pathways and apoptosis-related proteins. Experimental data revealed that the mode of cell death is the caspase-dependent mitochondrial apoptotic pathways. Excessive accumulation of ROS played a key role in this process, which is confirmed by alleviation of cytotoxicity upon pretreatment with NAC. Furthermore, we found that the combined treatment activated MAPK signaling pathway. The inhibition of p38 MAPK by pretreating with SB203580 block the combined treatment-induced apoptotic cell death. In conclusion, berberine-PDT could be used as a chemo-sensitizer by promoting cell death through activation of a ROS/p38/caspase cascade.

Apoptotic mechanism activated by blue light and cisplatinum in cutaneous squamous cell carcinoma cells

New approaches are being studied for the treatment of skin cancer. It has been reported that light combined with cisplatinum may be effective against skin cancer. In the present study, the effects of specific light radiations and cisplatinum on A431 cutaneous squamous cell carcinoma (cSCC) and HaCaT non-tumorigenic cell lines were investigated. Both cell lines were exposed to blue and red light sources for 3 days prior to cisplatinum treatment. Viability, apoptosis, cell cycle progression and apoptotic-related protein expression levels were investigated. The present results highlighted that combined treatment with blue light and cisplatinum was more effective in reducing cell viability compared with single treatments. Specifically, an increase in the apoptotic rate was observed when the cells were treated with blue light and cisplatinum, as compared to treatment with blue light or cisplatinum alone. Combined treatment with blue light and cisplatinum also caused cell cycle arrest at the S phase. Treatment with cisplatinum following light exposure induced the expression of apoptotic proteins in the A431 and HaCaT cell lines, which tended to follow different apoptotic mechanisms. On the whole, these data indicate that blue light combined with cisplatinum may be a promising treatment for cSCC.

Structure-activity insights of harmine targeting DNA, ROS inducing cytotoxicity with PARP mediated apoptosis against cervical cancer, anti-biofilm formation and in vivo therapeutic study

Harmine exhibits pH dependent structural equilibrium and possesses numerous biological and pharmacological activities. Mode and mechanism of DNA binding and its cytotoxicity were studied by multiple spectroscopic, calorimetric, molecular docking and in vitro apoptotic as well as in vivo biochemical and histological studies. It exists as cationic (structure I) and decationic form (structure II) in the pH range 3.0-7.8 and 8.5-12.4, respectively, with a pK_a of 8.0. Structure I at pH 6.8 binds strongly to DNA with a cooperative mode of binding of K_iω 1.03 × 10⁶ M^-1and stoichiometry of 5.0 nucleotide phosphates. Structure I stabilized DNA by 10 °C, showed85%quenching of fluorescence intensity, perturbation in circular dichroism, partial intercalation and enthalpy driven exothermic binding. While, structure II at pH 8.5 has very weak interaction with CT DNA. Cytotoxic potencies of structure I was tested on four different cancer cell lines along with normal embryonic cell. It showed maximum cytotoxicity with GI₅₀of 20 µM, against HeLa causing several apoptotic induction abilities. Harmine exhibited G2M arrest with ROS induced effective role in PARP mediated apoptosis as well as anti-inflammatory action on HeLa cells. Harmine further presented MIC and antibiofilm activity against Staphylococcus aureus in presence of <160 and 30 µg/ml, respectively. Mice with post harmine treatment (30 mg/kg b.w., I.P.) showed maximum recovery from damaged to near normal architecture of cervical epithelial cells. This study may be of prospective use in a framework to design novel beta carboline compounds for improved therapeutic applications in future against cervical cancer. HighlightsHarmine exists in structure I and structure II forms in the pH 6.8 and 8.5with a pK_a of 8.0.Structure I at pH 6.8 binds strongly to DNA compared to structure II.Structure I showed maximum cytotoxicity with GI₅₀ of 20 µM against HeLa.ROS mediated cytotoxicitywithG2M arrest with PARP mediated apoptosis was studied.Harmine (30µg/ml) exhibited antibiofilm activity against Staphylococcus aureus.Post harmine dose (30 mg/kg b.w., I.P.) in mice showed recovery of cervical epithelial cells.Communicated by Ramaswamy H. Sarma.

Investigation into the Effect of Photodynamic Therapy and Cisplatin on the Cervical Cancer Cell Line (A2780)

Introduction: Cervical cancer is recognized as one of the major causes of mortality among elderly women. Although there are several different therapeutic worldwide guidelines, many researchers have focused on screening new methodologies and technologies to elevate the efficiency of cervical cancer treatment. The simultaneous use of photodynamic therapy (PDT) along with chemotherapy as cisplatin has achieved good aims in the treatment of cervical cancer. Methods: A2780 cells were treated with cisplatin, photodynamic progress (laser with methylene blue as a photosensitizer compound) and a combination of cisplatin and PDT. The lithic effect of the laser, methylene blue and their combination and the IC50 value of cisplatin were calculated for each group. The amount of malondialdehyde (MDA) as membrane lipid peroxidation product and released lactate dehydrogenase was measured in the medium. The toxicity of each agent was evaluated by the MTT technique. Results: The results show that a combination of PDT and chemotherapeutic agent cisplatin caused a twofold decrease in viable cervical cancer cells compared to each therapeutic progress. The combination of both laser therapy and cisplatin enhanced cancer cell membrane disruption by increased membrane lipid peroxidation and apoptotic enzyme activation by the elevation of lactate dehydrogenase activity. Conclusion: The results indicated that cisplatin combined with PDT had a greater therapeutic effect on A2780 as a cervical cancer cell line. Therefore, PDT in combination with chemotherapy enhances the effectiveness of chemotherapeutic agents by the disruption of the cancer cell membrane and switching the apoptosis progress with less adverse effects.

Enhancement of Contact Lens Disinfection by Combining Disinfectant with Visible Light Irradiation

Multiple use contact lenses have to be disinfected overnight to reduce the risk of infections. However, several studies demonstrated that not only microorganisms are affected by the disinfectants, but also ocular epithelial cells, which come into contact via residuals at reinsertion of the lens. Visible light has been demonstrated to achieve an inactivation effect on several bacterial and fungal species. Combinations with other disinfection methods often showed better results compared to separately applied methods. We therefore investigated contact lens disinfection solutions combined with 405 nm irradiation, with the intention to reduce the disinfectant concentration of ReNu Multiplus, OptiFree Express or AOSept while maintaining adequate disinfection results due to combination benefits. Pseudomonads, staphylococci and E. coli were studied with disk diffusion assay, colony forming unit (cfu) determination and growth delay. A log reduction of 4.49 was achieved for P. fluorescens in 2 h for 40% ReNu Multiplus combined with an irradiation intensity of 20 mW/cm² at 405 nm. For AOSept the combination effect was so strong that 5% of AOSept in combination with light exhibited the same result as 100% AOSept alone. Combination of disinfectants with visible violet light is therefore considered a promising approach, as a reduction of potentially toxic ingredients can be achieved.

Transformation Chlorophyll a of Spirulina platensis to Chlorin e6 Derivatives and Several Applications

BACKGROUND

Spirulina platensis contains a large amount of chlorophylls, chlorophyll a, that are starting materials to synthesize functionalized chlorins. Chlorin e6 (Ce6) as well as its derivatives are second generation sensitizers using in photodynamic therapy (PDT) of various cancers. In this study, we transfer chlorophyll a of S. platensis to Ce6 derivatives and determine their several applications.

AIM

We aimed to evaluate the effects of Ce6 derivatives to treat cancer cells.

METHODS

Ce6 trimethylester was created from methyl pheophorbide a2 in S. platensis provided by the Hidumi Company, Nghe An province, Viet Nam. Hela cells were incubated with Ce6 trimethylester and the irradiated with the diode laser dose of 1.2 J/cm²/min through the system of filters £ 650 nm. MTT assay and clonogenic assay were used to determine survival rate and cloning efficiency of cells. Antimicrobial effect of Ce6 trimethylester with halogen light were studied with Propionibacterium acnes VTCC 0218 and Staphylococcus aureus VTCC 0173.

RESULTS

From dry biomass (700 g) of S. platensis, after extracting chlorophyll a and methanolysis, 4.2 g of methyl pheophorbide a was obtained. The reaction to give Ce6 trimethylester with 82% yield was performed with potassium hydroxide (KOH) in MeOH/THF/CHCl3. After irradiation with a 650 nm laser at 1.2 J, the cell viability in all samples decreased with Ce6 trimethylester treatment, the survival declining trend of Hela cells treated with Ce6 trimethylester were proportional when concentration of Ce6 trimethylester increased. The rate of colony formation was declined as the concentration of Ce6 trimethylester treated was increased. The growth of both S. aureus and P. acnes can be inactivated by Ce6 trimethylester PDT. The MIC99 value against P. acnes VTCC 0218 and S. aureus VTCC 0173 of Ce6 trimethylester with halogen light was 1.25 μg/ml.

CONCLUSION

The Ce6 trimethylester from S. platensis cultivated in Viet Nam could be used as a potential photosentizer for photodynamic therapy for treatment of cancer and acne.

Chitosan-Based Drug Delivery Systems for Optimization of Photodynamic Therapy: a Review

Drug delivery systems (DDS) can be designed to enrich the pharmacological and therapeutic properties of several drugs. Many of the initial obstacles that impeded the clinical applications of conventional DDS have been overcome with nanotechnology-based DDS, especially those formed by chitosan (CS). CS is a linear polysaccharide obtained by the deacetylation of chitin, which has potential properties such as biocompatibility, hydrophilicity, biodegradability, non-toxicity, high bioavailability, simplicity of modification, aqueous solubility, and excellent chemical resistance. Furthermore, CS can prepare several DDS as films, gels, nanoparticles, and microparticles to improve delivery of drugs, such as photosensitizers (PS). Thus, CS-based DDS are broadly investigated for photodynamic therapy (PDT) of cancer and fungal and bacterial diseases. In PDT, a PS is activated by light of a specific wavelength, which provokes selective damage to the target tissue and its surrounding vasculature, but most PS have low water solubility and cutaneous photosensitivity impairing the clinical use of PDT. Based on this, the application of nanotechnology using chitosan-based DDS in PDT may offer great possibilities in the treatment of diseases. Therefore, this review presents numerous applications of chitosan-based DDS in order to improve the PDT for cancer and fungal and bacterial diseases.

Hydrophilic Chlorin e6-Poly(amidoamine) Dendrimer Nanoconjugates for Enhanced Photodynamic Therapy

In photodynamic therapy (PDT), chlorin e6 (Ce6), with its high phototoxic potential and strong absorption of visible light, penetrates deeply into photodamaged tissue. However, despite this fact, the direct application of Ce6 to PDT has been limited by its low water solubility and poor cancer cell localization. To ameliorate this situation, we report herein on the use of a hydrophilic nanoconjugate (DC) comprised of Ce6 and poly(amidoamine) dendrimer, which improves the water solubility and intracellular uptake of Ce6, thereby enhancing PDT efficacy. The synthesis of DC was verified by ¹H nuclear magnetic resonance (NMR) analysis, and the coupling ratio of Ce6 introduced onto DC was 2.64. The prepared DC was spherical, with an average diameter of 61.7 ± 3.5 nm. In addition, the characteristic ultraviolet-visible absorption bands of DC in distilled water were similar to those of free Ce6 in dimethyl sulfoxide (DMSO), indicating that the Ce6 chromophore did not change upon conjugation. Investigation using fluorescence spectroscopy and confocal microscopy revealed a greater intracellular uptake of DC than of Ce6 alone. Moreover, DC exhibited significantly increased phototoxicity to human cervical cancer cells, mostly because of apoptotic cell death. These results imply that DC is a candidate for the clinical treatment of PDT.

Effective phthalocyanines mediated photodynamic therapy with doxorubicin or methotrexate combination therapy at sub-micromolar concentrations in vitro

To improve a cancer patient's quality of life, short treatment duration resulting in rapid tumour removal while sparing normal tissue are highly desirable. Photodynamic therapy (PDT) commonly applied in a single treatment, while often effective can be limited at low photosensitizer or light doses. Combination therapies can overcome the efficacy limitations while not increasing treatment-associated morbidity. Here the efficacy of combination therapy comprised of doxorubicin (DOX) or methotrexate (MTX) with Photosens mediated PDT was investigated in three cell lines in vitro, employing multiple incubation sequences. Photosense is a mixture of aluminium phthalocyanines with different sulfonation. The results demonstrated higher synergistic effects when DOX or MTX-mediated chemotherapy preceded PDT light activation by 24 h. MTX is marginally more cytotoxic than DOX, when combined with Photosens (AlPcS_2-4) mediated PDT. While MTX and DOX exposure prior to AlPcS_2-4 incubation may enhance mitochondrial localisation photosensitizer, the simultaneous targeting of DNA, proteins, and lipids of the combination therapies leads to the observed high cytotoxicity at sub μM drug doses.

Natural extracellular nanovesicles and photodynamic molecules: is there a future for drug delivery?

Photodynamic molecules represent an alternative approach for cancer therapy for their property (i) to be photo-reactive; (ii) to be not-toxic for target cells in absence of light; (iii) to accumulate specifically into tumour tissues; (iv) to be activable by a light beam only at the tumour site and (v) to exert cytotoxic activity against tumour cells. However, to date their clinical use is limited by the side effects elicited by systemic administration. Extracellular vesicles are endogenous nanosized-carriers that have been recently introduced as a natural delivery system for therapeutic molecules. We have recently shown the ability of human exosomes to deliver photodynamic molecules. Therefore, this review focussed on extracellular vesicles as a novel strategy for the delivery of photodynamic molecules at cancer sites. This completely new approach may enhance the delivery and decrease the toxicity of photodynamic molecules, therefore, represent the future for photodynamic therapy for cancer treatment.

Photodynamic therapy combined to cisplatin potentiates cell death responses of cervical cancer cells

BACKGROUND

Photodynamic therapy (PDT) has proven to be a promising alternative to current cancer treatments, especially if combined with conventional approaches. The technique is based on the administration of a non-toxic photosensitizing agent to the patient with subsequent localized exposure to a light source of a specific wavelength, resulting in a cytotoxic response to oxidative damage. The present study intended to evaluate in vitro the type of induced death and the genotoxic and mutagenic effects of PDT alone and associated with cisplatin.

METHODS

We used the cell lines SiHa (ATCC® HTB35™), C-33 A (ATCC® HTB31™) and HaCaT cells, all available at Dr. Christiane Soares' Lab. Photosensitizers were Photogem (PGPDT) and methylene blue (MBPDT), alone or combined with cisplatin. Cell death was accessed through Hoechst and Propidium iodide staining and caspase-3 activity. Genotoxicity and mutagenicity were accessed via flow cytometry with anti-gama-H2AX and micronuclei assay, respectively. Data were analyzed by one-way ANOVA with Tukey's posthoc test.

RESULTS

Both MBPDT and PGPDT induced caspase-independent death, but MBPDT induced the morphology of typical necrosis, while PGPDT induced morphological alterations most similar to apoptosis. Cisplatin predominantly induced apoptosis, and the combined therapy induced variable rates of apoptosis- or necrosis-like phenotypes according to the cell line, but the percentage of dead cells was always higher than with monotherapies. MBPDT, either as monotherapy or in combination with cisplatin, was the unique therapy to induce significant damage to DNA (double strand breaks) in the three cell lines evaluated. However, there was no mutagenic potential observed for the damage induced by MBPDT, since the few cells that survived the treatment have lost their clonogenic capacity.

CONCLUSIONS

Our results elicit the potential of combined therapy in diminishing the toxicity of antineoplastic drugs. Ultimately, photodynamic therapy mediated by either methylene blue or Photogem as monotherapy or in combination with cisplatin has low mutagenic potential, which supports its safe use in clinical practice for the treatment of cervical cancer.

Drug Delivery Approaches for the Treatment of Cervical Cancer

Cervical cancer is a highly prevalent cancer that affects women around the world. With the availability of new technologies, researchers have increased their efforts to develop new drug delivery systems in cervical cancer chemotherapy. In this review, we summarized some of the recent research in systematic and localized drug delivery systems and compared the advantages and disadvantages of these methods.

Photodynamic therapy as an antifungal treatment

Photodynamic therapy (PDT) involves the systemic or topical application of a photosensitizer (PS), alongside the selective illumination of the target lesion with light of an appropriate wavelength, in order to promote localized oxidative photodamage and subsequent cell death. Numerous studies have demonstrated that PDT is highly effective in the destruction of fungi in vitro. The mechanism underlying the effects of PDT results from the photons of visible light of an appropriate wavelength interacting with the intracellular molecules of the PS. Reactive species are produced as a result of the oxidative stress caused by the interaction between the visible light and the biological tissue. At present, no antifungal treatment based on PDT has been licensed. However, antifungal PDT is emerging as an area of interest for research.

Nanotechnology-Based Drug Delivery Systems for Photodynamic Therapy of Cancer: A Review

Photodynamic therapy (PDT) is a promising alternative approach for improved cancer treatment. In PDT, a photosensitizer (PS) is administered that can be activated by light of a specific wavelength, which causes selective damage to the tumor and its surrounding vasculature. The success of PDT is limited by the difficulty in administering photosensitizers (PSs) with low water solubility, which compromises the clinical use of several molecules. Incorporation of PSs in nanostructured drug delivery systems, such as polymeric nanoparticles (PNPs), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), gold nanoparticles (AuNPs), hydrogels, liposomes, liquid crystals, dendrimers, and cyclodextrin is a potential strategy to overcome this difficulty. Additionally, nanotechnology-based drug delivery systems may improve the transcytosis of a PS across epithelial and endothelial barriers and afford the simultaneous co-delivery of two or more drugs. Based on this, the application of nanotechnology in medicine may offer numerous exciting possibilities in cancer treatment and improve the efficacy of available therapeutics. Therefore, the aim of this paper is to review nanotechnology-based drug delivery systems for photodynamic therapy of cancer.

Angiostatic treatment prior to chemo- or photodynamic therapy improves anti-tumor efficacy

Tumor vasculature is known to be poorly organized leading to increased leakage of molecules to the extravascular space. This process can potentially increase interstitial fluid pressure impairing intra-tumoral blood flow and oxygen supply, and can affect drug uptake. Anti-angiogenic therapies are believed to reduce vascular permeability, potentially reducing interstitial fluid pressure and improving the extravasation of small molecule-based chemotherapeutics. Here we show that pretreatment of human ovarian carcinoma tumors with sub-optimal doses of the VEGFR targeting tyrosine kinase inhibitor axitinib, but not the EGFR targeting kinase inhibitor erlotinib, induces a transient period of increased tumor oxygenation. Doxorubicin administered within this window was found to enter the extravascular tumor space more rapidly compared to doxorubicin when applied alone or outside this time window. Treatment with the chemotherapeutics, doxorubicin and RAPTA-C, as well as applying photodynamic therapy during this period of elevated oxygenation led to enhanced tumor growth inhibition. Improvement of therapy was not observed when applied outside the window of increased oxygenation. Taken together, these findings further confirm the hypothesis of angiostasis-induced vascular normalization and also help to understand the interactions between anti-angiogenesis and other anti-cancer strategies.