Enhancement of the in vitro anticancer photo-sonodynamic combination therapy activity of cationic thiazole-phthalocyanines using gold and silver nanoparticles

Hybrid Sono-Photodynamic Combination Therapy Mediated by Water-Soluble Gallium Phthalocyanine Enhances the Cytotoxic Effect against Breast Cancer Cell Lines

Breast cancer is a life-threatening disease that is gaining increasing importance due to its rising incidence, highlighting the need for novel treatment methods with the least disadvantages. Recently, scientists have focused on developing therapeutic treatment modalities for effective cancer treatment. In contrast to conventional cancer treatment methods such as immunotherapy, surgery, chemotherapy, or radiotherapy, photodynamic therapy (PDT) is gaining prominence. Besides, sonodynamic treatment (SDT) is a noninvasive therapeutic approach that uses ultrasound to induce high tissue penetration. In both methods, sensitizers are activated to generate cytotoxic reactive oxygen species such as •OH and 1O2. In particular, the combined use of hybrid and complementary treatment methods has become an important modality in cancer treatment in recent years. Sono-photodynamic therapy (SPDT), which is an important method applied in combination with PDT and SDT, has started to be preferred in terms of reducing potential side effects compared to monotherapy. One of the most important types of sensitizers used in PDT and SDT is known as phthalocyanines (Pcs). Motivated by these facts, this research presents the sono-photochemical, in vitro cytotoxicity, and theoretical evaluation of water-soluble gallium phthalocyanine (GaPc). The results indicate that the quantum yield of the generation of singlet oxygen increased in sono-photochemical studies (ΦΔ = 0.94), compared to photochemical studies (ΦΔ = 0.72). In vitro analyses revealed that GaPc did not exhibit significant cytotoxic effects at the specified varying concentration doses (1-20 μM). Furthermore, GaPc-mediated SPDT triggered cell death by inducing reactive oxygen species formation in the breast cancer cell line (MCF-7). The interaction mechanism of the GaPc with EGFR and VEGFR2 target proteins, which are critical regulators of metastasis, proliferation, and angiogenesis, was investigated by molecular docking simulation. GaPc has effective binding affinities against target proteins, and this affinity was found to be the highest against VEGFR2. Molecular docking results showed a good correlation with the obtained biological results. Eventually, this molecular building of the efficient water-soluble phthalocyanine-based sensitizer is a potential therapeutic for PDT, SDT, and SPDT applications.

Monitoring of singlet oxygen generation of a novel Schiff-base substituted silicon phthalocyanines by sono-photochemical studies and in vitro activities on prostate cancer cell

This study demonstrates the potential of sono-photodynamic therapy as an effective approach for enhancing singlet oxygen generation using the synthesized Schiff-base diaxially substituted silicon phthalocyanines. In photochemical studies, the singlet oxygen quantum yields (Φ∆) were determined as 0.43 for Si1a, 0.94 for Q-Si1a, 0.58 for S-Si1a, and 0.49 for B-Sia1. In sono-photochemical studies, the Φ∆ values were reached to 0.67 for Si1a, 1.06 for Q-Si1a, 0.65 for S-Si1a, and 0.67 for B-Sia1. In addition, this study demonstrates the therapeutic efficacy of phthalocyanines synthesized as sensitizers on the PC3 prostate cancer cell line through in vitro experiments. The application of these treatment modalities exhibited notable outcomes, leading to a substantial decrease in cell viability within the PC3 prostate cancer cell line. These findings highlight the potential of utilizing these synthesized phthalocyanines as promising therapeutic agents for prostate cancer treatment.

External Stimuli-Responsive Strategies for Surface Modification of Orthopedic Implants: Killing Bacteria and Enhancing Osteogenesis

Bacterial infection and insufficient osteogenic activity are the main causes of orthopedic implant failure. Conventional surface modification methods are difficult to meet the requirements for long-term implant placement. In order to better regulate the function of implant surfaces, especially to improve both the antibacterial and osteogenic activity, external stimuli-responsive (ESR) strategies have been employed for the surface modification of orthopedic implants. External stimuli act as "smart switches" to regulate the surface interactions with bacteria and cells. The balance between antibacterial and osteogenic capabilities of implant surfaces can be achieved through these specific ESR manifestations, including temperature changes, reactive oxygen species production, controlled release of bioactive molecules, controlled release of functional ions, etc. This Review summarizes the recent progress on different ESR strategies (based on light, ultrasound, electric, and magnetic fields) that can effectively balance antibacterial performance and osteogenic capability of orthopedic implants. Furthermore, the current limitations and challenges of ESR strategies for surface modification of orthopedic implants as well as future development direction are also discussed.

Design consideration of phthalocyanines as sensitizers for enhanced sono-photodynamic combinatorial therapy of cancer

Cancer remains one of the diseases with the highest incidence and mortality globally. Conventional treatment modalities have demonstrated threatening drawbacks including invasiveness, non-controllability, and development of resistance for some, including chemotherapy, radiation, and surgery. Sono-photodynamic combinatorial therapy (SPDT) has been developed as an alternative treatment modality which offers a non-invasive and controllable therapeutic approach. SPDT combines the mechanism of action of sonodynamic therapy (SDT), which uses ultrasound, and photodynamic therapy (PDT), which uses light, to activate a sensitizer and initiate cancer eradication. The use of phthalocyanines (Pcs) as sensitizers for SPDT is gaining interest owing to their ability to induce intracellular oxidative stress and initiate toxicity under SDT and PDT. This review discusses some of the structural prerequisites of Pcs which may influence their overall SPDT activities in cancer therapy.

Sonophotochemical and photochemical efficiency of thiazole-containing metal phthalocyanines and their gold nanoconjugates

This study presents the synthesis of some metal {M = Zn(II), Lu(III), Si(IV)} phthalocyanines bearing chlorine and 2-(4-methylthiazol-5-yl) ethoxy groups at peripheral or axial positions. The newly synthesized metal phthalocyanines were characterized by applying FT-IR, 1H NMR, mass, and UV-Vis spectroscopic approaches. Additionally, the surface of gold nanoparticles was modified with zinc(II) and silicon(IV) phthalocyanines. The resultant nanoconjugates were characterized using TEM images. Moreover, the effect of metal ions and position of substituent, and gold nanoparticles on the photochemical and sonophotochemical properties of the studied phthalocyanines was investigated. The highest singlet oxygen quantum yield was obtained for the lutetium phthalocyanine by applying photochemical and sonophotochemical methods. However, the linkage of the zinc(II) and silicon(IV) phthalocyanines to the surface of gold nanoparticles improved significantly their singlet oxygen generation capacities.

Comparatively sonophotochemical and photochemical studies of phthalocyanines with cationic substituents on nonperipheral positions

The term sonophotodynamic therapy (SPDT) refers to a combination of sonodynamic therapy (SDT) and photodynamic therapy (PDT), in which the efficacy of the treatment is boosted by utilizing the proper amount of a sensitizer that is responsive to both light and ultrasound. Although it has been proven in photophysicochemical studies that SPDT enhances singlet oxygen production, related studies in the literature are very limited. Considering this situation, this study aims to investigate the efficacy of synthesized phthalocyanines in terms of PDT and SPDT. The singlet oxygen quantum values calculated as 0.13 for 5, 0.44 for 6, and 0.61 for 7 in photochemical (PDT) application increased to 0.18, 0.86, and 0.92, respectively, with sonophotochemical (SPDT) application. According to the results, singlet oxygen production was more efficient with SPDT. This work will add to the body of knowledge on employing the SPDT approach to increase singlet oxygen generation.

Design of N-heterocycle based-phthalonitrile/metal phthalocyanine-silver nanoconjugates for cancer therapies

This study reports the anticancer properties of carbazole-containing phthalonitrile/phthalocyanine-modified silver nanoparticles for the first time. In this study, a new mono-substituted phthalonitrile namely 3-[9H-carbazole-9-ethoxy]phthalonitrile and its metal phthalocyanines {M = Zn, Co, and Mn(Cl)} were synthesized by template cyclotetramerization of phthalonitrile derivatives. The newly synthesized compounds were characterized using UV-vis, FT-IR, 1H NMR, 13C NMR, and mass spectroscopy. The resultant compounds were successfully linked to the surface of silver nanoparticles. The characterization of the surficial modification was carried out by applying the TEM technique. The cytotoxic activities of the studied nanoconjugates were tested against A549, DLD-1, and Wi38 cell lines by performing a (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay with/without irradiation. Although the functionalization of silver nanoparticles increased the solubility of phthalocyanines in aqueous media, the presence of phthalonitrile/phthalocyanine derivatives on the silver nanoparticles' surface improved their biological properties. All the studied biological candidates exhibited antiproliferative activities against the cell lines. The IC50 values calculated were between 6.80 and 97.99 μM against the studied cell lines in the dark. However, the IC50 values determined were between 3.11 and 88.90 μM with irradiation. The highest IC50 values obtained were 3.11 and 3.52 μM against the DLD-1 cell line for nanoconjugates 1-AgNP and 3-AgNP, respectively. The findings indicated that the compounds may be utilized as anticancer agents after further studies.

The in-vitro proliferation-suppression of MCF-7 and HeLa cell lines mediated by differently substituted ionic phthalocyanines in sonodynamic therapy supplemented-photodynamic therapy

This work focuses on the study of the effects of the ultrasonic frequency (MHz) and power (W.cm^-2) on the stability, reactive oxygen species yields and cytotoxicity activities of differently substituted ionic phthalocyanines (Pcs) in sonodynamic therapy (SDT). Four ultrasonic parameters were investigated: Par I (1 MHz: 1 W.cm^-2), Par II (1 MHz: 2 W.cm^-2), Par III (3 MHz: 1 W.cm^-2) and Par IV (3 MHz: 2 W.cm^-2). A higher degradation of the Pcs was observed with increasing power at the Par II. Two reactive oxygen species (ROS) were detected in the ultrasound treated Pcs: singlet oxygen and hydroxyl radicals. Due to minimal degradation of most Pcs, Par I was chosen for SDT, photodynamic therapy (PDT), and photo-sonodynamic therapy (PSDT) against Michigan Cancer Foundation-7 and Henrietta Lacks cancer cell lines. PSDT generally showed improved therapeutic efficacies of the Pcs compared to the SDT and PDT mono treatments.