A novel pro-apoptotic role of zinc octacarboxyphthalocyanine in melanoma me45 cancer cell's photodynamic therapy (PDT)

Synergistic action of combining photodynamic therapy with immunotherapy for eradicating solid tumors in animal models: A systematic review

Malignancies maintain a high rate of mortality worldwide each year, requiring the development of novel therapeutic platforms. Immunotherapy approaches are considered a revolutionary treatment for overcoming malignancies. Photodynamic therapy (PDT) has attracted significant attention in various cancer types. Recent progress in cancer therapies has underscored the potential of combining PDT with immunotherapy. This approach can improve therapeutic outcomes by directly eliminating tumor cells and boosting immune responses for sustained anti-tumor effects in the whole body. This study aims to determine the relative efficacy of combining PDT with immunotherapy compared to PDT alone. Following the PRISMA guidance, an extensive literature review was conducted utilizing Scopus, Web of Science, and PubMed to identify high-quality preclinical studies exploring various aspects of PDT combined with immunotherapy. The adopted PICO framework included studies with rigorous experimental designs and relevant outcomes. The present review reveals the characteristics of tumor models, delivery systems, photosensitizers, and immunotherapy approaches. Key findings indicate that the combined PDT-immunotherapy approach shows promise in treating multiple tumors according to their size, therapeutic biomarkers, and inhibition of distant tumors. Finally, this integrated therapeutic strategy holds significant promise for advancing cancer treatment paradigms by potentiating each treatment efficacy; however, its clinical utility requires careful consideration of the associated challenges.

Expression and Clinical Significance of Lymphocyte Subpopulations and Peripheral Inflammatory Markers in Glioma

Purpose

Patients with glioma often fail to achieve satisfactory outcomes despite receiving surgery, radiotherapy, and chemotherapy. Photodynamic therapy (PDT) shows promise in addressing the limitations of traditional treatments. However, the immunological effects of PDT in glioma patients remain underexplored. This study aims to fill this gap by analyzing lymphocyte subpopulations and inflammatory markers in glioma patients undergoing PDT-assisted surgery.

Patients and Methods

To enhance our comprehension of the immunobiology of glioma within a clinical framework, we conducted a retrospective analysis of glioma patients from September 2019 to December 2023. Peripheral blood lymphocyte subpopulations (CD3+, CD19+, CD4+, CD8+, CD4+/CD8+) and hematological inflammatory factors were compared among 18 patients who underwent surgery with PDT, 10 patients treated with surgery alone, and healthy controls. Additionally, lymphocyte subpopulations from 48 healthy individuals and hematology inflammatory factors from 38 healthy controls were regarded as controls.

Results

PDT-assisted surgery resulted in significant alterations in lymphocyte subpopulations and inflammatory markers before and after treatment, particularly in CD4+ and CD8+ T cells. PDT-treated patients demonstrated a superior therapeutic response compared to surgery alone (P=0.035). Notably, primary glioma patients had more prolonged overall survival than recurrent glioma patients (P=0.039).

Conclusion

PDT-assisted surgery significantly affects lymphocyte subpopulations and inflammatory markers, enhancing immune response in glioma patients. These findings support the use of PDT as an effective adjuvant therapy. Monitoring lymphocyte subpopulations and inflammatory markers may be valuable for glioma prognosis and treatment optimization.

Gallium octacarboxyphthalocyanine hydroxide as a potential pro-apoptotic drug against cancer skin cells

Novel anticancer strategies reduce side effects on healthy tissues by elevating the lethal abilities of cancer cells. The development of effective particles with good bioavailability and selectivity remains problematic. For undesirable features, green chemistry is used to synthesize the best compounds, or natural-based particles are improved. Photodynamic therapy (PDT), modelled on phthalocyanines (Pcs), still delivers second-generation sensitizers which are complemented with metal ions, such as Zn2+, Al3+, or Ga3+. Gallium octacarboxyphthalocyanine hydroxide (Ga(OH)PcOC), was designed for skin cancer treatment, and was used as a pro-apoptotic and pro-oxidative agent on normal skin cell lines, fibroblasts (NHDF), and keratinocytes (HaCaT), with promising selectivity against melanoma cancer cells (Me45) in vitro. Compared to the previous reported findings, where the ZnPcOC acted on the skin cell lines at higher doses, the sensitivities to the Ga(OH)PcOC allows for an effective reduction of the sensitizer dose. The effective dose, for a novel Ga(OH)PcOC particle, was significantly reduced from 30 µM to 6 µM on Me45 cancer cells, tested using 24 h MTT viability, as well as cytometric pro-oxidative and pro-apoptotic assays. The promising photosensitizer did not reduce viability in normal fibroblasts and keratinocytes without reactive oxygen species (ROS) elevation or apoptosis induction. The improvement to the previous findings is better Ga-based photosensitizer selectivity against the cancer Me45 cells, then observed in Zn-based compounds.

Combinatorial approach of cannabidiol and active-targeted-mediated photodynamic therapy in malignant melanoma treatment

Malignant melanoma (MM) continues to claim millions of lives around the world due to its limited therapeutic alternatives. Photodynamic therapy (PDT) has gained popularity in cancer treatment due it increased potency and low off-target toxicity. Studies have pointed out that the heterogeneity of MM tumours reduces the efficacy of current therapeutic approaches, including PDT, leading to high chances of recurrences post-treatment. Accumulating evidence suggests that cannabidiol (CBD), a non-psychoactive derivative of cannabis, can synergise with various anticancer agents to increase their efficacy. However, CBD demonstrates low bioavailability, which is attributed to factors relating to poor water compatibility, poor absorption and rapid metabolism. Nanotechnology offers tools that address these issues and enhance the biological efficiency and targeted specificity of anticancer agents. Herein, we highlighted the standard therapeutic modalities of MM and their pitfalls, as well as pointed out the need for further investigation into PDT combination therapy with CBD.

The synthesis of novel water-soluble zinc (II) phthalocyanine based photosensitizers and exploring of photodynamic therapy activities on the PC3 cancer cell line

In this study, Schiff base substituted phthalocyanine complexes (Zn1c, Zn2c) and their quaternized derivatives (Q-Zn1c, Q-Zn2c) were synthesized for the first time. Their structures have been characterized by FT-IR, 1H-NMR, UV-Vis, mass spectrometry and elemental analysis as well as. The photophysicochemical properties (fluorescence, singlet oxygen and photodegradation quantum yield) of these novel complexes were investigated in dimethylsulfoxide (DMSO) for both non-ionic and quaternized cationic phthalocyanine complexes and in aqueous solution for quaternized cationic phthalocyanine complexes. Water soluble cationic phthalocyanine compounds gave good singlet oxygen quantum yield (0.65 for Q-Zn1c, 0.66 for Q-Zn2c in DMSO; 0.65 for Q-Zn2c in aqueous solution). The binding of Q-Zn1c and Q-Zn2c to BSA/DNA was studied by using UV-Vis and fluorescence spectroscopy and these. Studies indicate that the mechanism of BSA quenching by quaternized zinc(II) phthalocyanines was static quenching. Quaternized zinc(II) phthalocyanines interacted with ct-DNA by intercalation. Quaternized zinc(II) phthalocyanines caused a decrease in cell viability and triggered apoptotic cell death after PDT was applied at a concentration that did not have a toxic effect on their own. Q-Zn1c and Q-Zn2c mediated PDT reduced the activity of SOD, CAT, GSH while increased MDA level in the prostate cancer cells. Furthermore, expression of apoptotic proteins after PDT was examined. The results revealed that the synthesized water soluble quaternized zinc(II) phthalocyanine complexes (Q-Zn1c and Q-Zn2c) are promising potential photosensitizers for PDT.

Investigation of ROS generating capacity of curcumin-loaded liposomes and its in vitro cytotoxicity on MCF-7 cell lines using photodynamic therapy

Photodynamic therapy (PDT) is highly efficient in eradicating targetlesions by using photosensitizers (PS) triggered by external light energy. Nanotechnology may help increase the solubility and effective delivery of PS towards improving its efficacy. Curcumin (Cur) was used as a natural PS for PDT in the present work. Briefly, curcumin was encapsulated in liposomes (LPs) using the thin film hydration method and optimized using the QbD approach through the Box-Behnken Design (BBD) to optimize the responses like entrapment efficiency and drug loading with a smaller vesicle size. The in vitro release studies performed using a dialysis bag (MWCO 12 KDa) suggested a sustained release of the Cur over 72 h in pH 7.4 PBS following the Weibull drug release kinetics. In addition, the ROS generating capabilities upon application of blue light (460 nm) and resulting cytotoxicity were evaluated in MCF-7 cell lines. The Cur-loaded liposome exhibited significant ROS generation and cytotoxicity to the cancer cells than free curcumin. Thus, the Cur-loaded liposomes could be used to treat breast cancer with photodynamic therapy.

Tri- and Pentacyclic Azaphenothiazine as Pro-Apoptotic Agents in Lung Carcinoma with a Protective Potential to Healthy Cell Lines

The phenothiazine derivatives, tricyclic 10H-3,6-diazaphenothiazine (DPT-1) and pentacyclic 7-(3′-dimethylaminopropyl)diquinothiazine (DPT-2), have recently been shown to exhibit promising anticancer activities in vitro. In this report, we demonstrated that DPT-1 and DPT-2 could be pro-apoptotic agents in lung carcinoma, the human lung carcinoma A549 and non-small lung carcinoma H1299, in the range of IC50 = 1.52–12.89 µM, with a protective potential to healthy cell lines BEAS-2B and NHDF. The compounds showed higher activity in the range of the tested concentrations and low cytotoxicity in relation to normal healthy cells than doxorubicin, used as the reference drug. The cytostatic potential of DPT-1 and DPT-2 was demonstrated with the use of MTT assay. Cell cycle analysis via flow cytometry using Annexin-V assay showed the pro-apoptotic and pro-necrotic role of the studied diazaphenothiazines in the cell cycle. DPT-1 and DPT-2 initiated a biological response in the investigated cancer models with a different mechanism and at a different rate. Based on these findings, it can be concluded that DPT-1 and DPT-2 have potential as chemotherapeutic agents.

Engineered Nanostructured Photocatalysts for Cancer Therapy

The present review aims at highlighting recent advances in the development of photocatalysts devoted to cancer therapy applications. We pay especial attention to the engineering aspects of different nanomaterials including inorganic semiconductors, organic-based nanostructures, noble metal-based systems or synergistic hybrid heterostructures. Furthermore, we also explore and correlate structural and optical properties with their photocatalytic capability to successfully performing in cancer-related therapies. We have made an especial emphasis to introduce current alternatives to organic photosensitizers (PSs) in photodynamic therapy (PDT), where the effective generation of reactive oxidative species (ROS) is pivotal to boost the efficacy of the treatment. We also overview current efforts in other photocatalytic strategies to tackle cancer based on photothermal treatment, starvation therapy, oxidative stress unbalance via glutathione (GSH) depletion, biorthogonal catalysis or local relief of hypoxic conditions in tumor microenvironments (TME).

Synthesis and Preliminary Anticancer Activity Assessment of N-Glycosides of 2-Amino-1,3,4-thiadiazoles

The addition of 2-amino-1,3,4-thiadiazole derivatives with parallel iodination of differently protected glycals has been achieved using a double molar excess of molecular iodine under mild conditions. The corresponding thiadiazole derivatives of N-glycosides were obtained in good yields and anomeric selectivity. The usage of iodine as a catalyst makes this method easy, inexpensive, and successfully useable in reactions with sugars. Thiadiazole derivatives were tested in a panel of three tumor cell lines, MCF-7, HCT116, and HeLa. These compounds initiated biological response in investigated tumor models in a different rate. The MCF-7 is resistant to the tested compounds, and the cytometry assay indicated low increase in cell numbers in the sub- G1 phase. The most sensitive are HCT-116 and HeLa cells. The thiadiazole derivatives have a pro-apoptotic effect on HCT-116 cells. In the case of the HeLa cells, an increase in the number of cells in the sub-G1- phase and the induction of apoptosis was observed.

Nanoparticle-Based Drug Delivery Systems for Photodynamic Therapy of Metastatic Melanoma: A Review

Metastatic melanoma (MM) is a skin malignancy arising from melanocytes, the incidence of which has been rising in recent years. It poses therapeutic challenges due to its resistance to chemotherapeutic drugs and radiation therapy. Photodynamic therapy (PDT) is an alternative non-invasive modality that requires a photosensitizer (PS), specific wavelength of light, and molecular oxygen. Several studies using conventional PSs have highlighted the need for improved PSs for PDT applications to achieve desired therapeutic outcomes. The incorporation of nanoparticles (NPs) and targeting moieties in PDT have appeared as a promising strategy to circumvent various drawbacks associated with non-specific toxicity, poor water solubility, and low bioavailability of the PSs at targeted tissues. Currently, most studies investigating new developments rely on two-dimensional (2-D) monocultures, which fail to accurately mimic tissue complexity. Therefore, three-dimensional (3-D) cell cultures are ideal models to resemble tumor tissue in terms of architectural and functional properties. This review examines various PS drugs, as well as passive and active targeted PS nanoparticle-mediated platforms for PDT treatment of MM on 2-D and 3-D models. The overall findings of this review concluded that very few PDT studies have been conducted within 3-D models using active PS nanoparticle-mediated platforms, and so require further investigation.

Imaging and detection of cell apoptosis byIn vitrophotodynamic therapy applications of zinc (II) phthalocyanine on human melanoma cancer

This study aims to investigate the photodynamic therapy (PDT) effects on MeWo (human melanoma cells) and HaCaT (normal human keratinocyte cells) by light stimulation of different concentrations of Zinc (II)-tetra-tert-butyl-phthalocyaninato (ZnPc). MTT viability assay data indicated that a 25 μM concentration of ZnPc is cytotoxic to the melanoma cancer cells while this concentration of ZnPc is not cytotoxic for the HaCaT cell line. Moreover, the results showed that photoactivated ZnPc at 12.5 μM concentration reduced the cell viability of the MeWo cell line to about 50 %. At this photosensitizing concentration, the efficacy of light doses of 20, 30, 40, and 50 J/cm² was evaluated against MeWo and HaCaT cells. ZnPc at a concentration of 12.5 μM activated with a light dose of 50 J/cm² was the most efficient for the killing of MeWo cells. In conclusion, the 12.5 μM of ZnPc with the treatment light dose of 50 J/cm² from a RED light source was adequate to destroy MeWo cells by the ROS-induced apoptosis mechanism. It also exhibited low killing effects on healthy HaCaT cells. These findings are supported by the results of apoptosis with the Annexin V & Dead Cell Kit and fluorescence imaging.

Coordination Complexes as a New Generation Photosensitizer for Photodynamic Anticancer Therapy

Photodynamic therapy (PDT) has become an alternative to standard cancer treatment methods such as surgery, chemotherapy and radiotherapy. The uniqueness of this method relies on the possibility of using various photosensitizers (PS) that absorb and convert light emission in radical oxygen-derived species (ROS). They can be present alone or in the presence of other compounds such as metal organic frameworks (MOFs), non-tubules or polymers. The interaction between DNA and metal-based complexes plays a key role in the development of new anti-cancer drugs. The use of coordination compounds in PDT has a significant impact on the amount ROS generated, quantum emission efficiency (Φem) and phototoxic index (PI). In this review, we will attempt to systematically review the recent literature and analyze the coordination complexes used as PS in PDT. Finally, we compared the anticancer activities of individual coordination complexes and discuss future perspectives. So far, only a few articles link so many transition metal ion coordination complexes of varying degrees of oxidation, which is why this review is needed by the scientific community to further expand this field worldwide. Additionally, it serves as a convenient collection of important, up-to-date information.

Co-administration of zinc phthalocyanine and quercetin via hybrid nanoparticles for augmented photodynamic therapy

The photodynamic anticancer activity of a photosensitizer can be further increased by co-administration of a flavonoid. However, this requires that both molecules must be effectively accumulated at the tumor site. Hence, in order to enhance the activity of zinc phthalocyanine (ZnPc, photosensitizer), it was co-encapsulated with quercetin (QC, flavonoid) in lipid polymer hybrid nanoparticles (LPNs) developed using biodegradable & biocompatible materials and prepared using a single-step nanoprecipitation technique. High stability and cellular uptake, sustained release, inherent fluorescence, of ZnPC were observed after encapsulation in the LPNs, which also showed a higher cytotoxic effect in breast carcinoma cells (MCF-7) compared to photodynamic therapy (PDT) alone. In vivo studies in tumor-bearing Sprague Dawley rats demonstrated that the LPNs were able to deliver ZnPc and QC to the tumor site with minimal systemic toxicity and increased antitumor effect. Overall, the photodynamic effect of ZnPc was synergized by QC. This strategy could be highly beneficial for cancer management in the future while nullifying the side effects of chemotherapy.

Progress in Clinical Trials of Photodynamic Therapy for Solid Tumors and the Role of Nanomedicine

Current research to find effective anticancer treatments is being performed on photodynamic therapy (PDT) with increasing attention. PDT is a very promising therapeutic way to combine a photosensitive drug with visible light to manage different intense malignancies. PDT has several benefits, including better safety and lower toxicity in the treatment of malignant tumors over traditional cancer therapy. This reasonably simple approach utilizes three integral elements: a photosensitizer (PS), a source of light, and oxygen. Upon light irradiation of a particular wavelength, the PS generates reactive oxygen species (ROS), beginning a cascade of cellular death transformations. The positive therapeutic impact of PDT may be limited because several factors of this therapy include low solubilities of PSs, restricting their effective administration, blood circulation, and poor tumor specificity. Therefore, utilizing nanocarrier systems that modulate PS pharmacokinetics (PK) and pharmacodynamics (PD) is a promising approach to bypassing these challenges. In the present paper, we review the latest clinical studies and preclinical in vivo studies on the use of PDT and progress made in the use of nanotherapeutics as delivery tools for PSs to improve their cancer cellular uptake and their toxic properties and, therefore, the therapeutic impact of PDT. We also discuss the effects that photoimmunotherapy (PIT) might have on solid tumor therapeutic strategies.

Anticancer activity of functional polysuccinates with N-acetyl-cysteine in side chains

The synthesis and characteristics of functional polyesters with a potential anticancer activity have been described, followed by a post-modification process of biologically active polymers. First, biodegradable functional polysuccinates possessing pendant allyl groups, that are susceptible to thiol-ene reaction, were obtained by polyaddition of succinic anhydride and allyl glycidyl ether. The functionality of such polyesters was regulated by replacing a part of unsaturated glycidyl ether with saturated ones. Polymers containing 20-100% mers with allyl groups were reacted with N-acetyl-cysteine (NAC). The use of simple click reaction allowed obtaining polyesters containing different amounts of N-acetyl-cysteine in side chains. The thus obtained polymers with a molecular weight of several thousand are characterized by solubility in methanol as opposed to their initial precursors. Modified polyesters show no toxicity to normal human keratinocytes (HaCaT) cells, similar to the NAC in normal human fibroblasts (NHDF), whereas the anticancer activities were observed against squamous carcinoma (SCC-25), and melanoma (Me45) cells. A standard colorimetric assay (MTS), to assessing cells viability and cytotoxicity of tested compounds, was performed against NHDF for NAC, HaCaT, SCC-25, and Me45 cells, within 24-144 h long-term expositions. Neither contact with NAC alone, and tested materials, nor long incubation decreased normal cell viability or induced inflammation. That reassumed the potential of anticancer activities of tested materials, with the tendency to visible selectivity against cancer cell lines in vitro, confirmed with live microscopic imaging against the Me45 cell line.

Susceptibility and Resistance Mechanisms During Photodynamic Therapy of Melanoma

Melanoma is the most aggressive malignant skin tumor and arises from melanocytes. The resistance of melanoma cells to various treatments results in rapid tumor growth and high mortality. As a local therapeutic modality, photodynamic therapy has been successfully applied for clinical treatment of skin diseases. Photodynamic therapy is a relatively new treatment method for various types of malignant tumors in humans and, compared to conventional treatment methods, has fewer side effects, and is more accurate and non-invasive. Although several in vivo and in vitro studies have shown encouraging results regarding the potential benefits of photodynamic therapy as an adjuvant treatment for melanoma, its clinical application remains limited owing to its relative inefficiency. This review article discusses the use of photodynamic therapy in melanoma treatment as well as the latest progress made in deciphering the mechanism of tolerance. Lastly, potential targets are identified that may improve photodynamic therapy against melanoma cells.

S-seco-porphyrazine as a new member of the seco-porphyrazine family - Synthesis, characterization and photocytotoxicity against cancer cells

An important subgroup within the porphyrazine (Pz) family constitutes seco-porphyrazines, in the chemical structure of which one pyrrole unit is opened in the oxidative process. So far, there are only limited data on N-seco- and C-seco-Pzs. Here, the synthesis of a novel member of the Pzs seco-family, represented by an S-seco-tribenzoporphyrazine analogue, 22,23-bis(4-(3,5-dibutoxycarbonylphenoxy)butylsulfanyl)tribenzo[b,g,l]-22,23-dioxo-22,23-seco-porphyrazinato magnesium(II), is reported, with moderate 34% yield. The new derivative was characterized using NMR spectroscopy, UV-Vis spectroscopy, and mass spectrometry. In the photochemical study performed following the indirect chemical method with 1,3-diphenylisobenzofuran, S-seco-Pz revealed a high singlet oxygen quantum yield of 0.27 in DMF. Potential photocytotoxicity of S-seco-Pz was assessed in vitro on three cancer cell lines - two oral squamous cell carcinoma cell lines derived from the tongue (CAL 27, HSC-3) and human cervical epithelial adenocarcinoma cells (HeLa). In the biological study, the macrocycle was tested in its free form and after loading into liposomes. It is worth noting that S-seco-Pz was found to be non-toxic in the dark, with cell viability levels over 80%. The photocytotoxic IC₅₀ values for free S-seco-Pz were 0.61, 0.18, and 4.1 µM for CAL 27, HSC-3 and HeLa cells, respectively. Four different liposomal compositions were analyzed, and the cationic liposomes revealed the highest photokilling efficacy, with the IC₅₀ values for CAL 27, HSC-3, and HeLa cells at 0.24, 0.25, and 0.31 µM, respectively. The results of the photocytotoxicity study indicate that the new S-seco-tribenzoporphyrazine can be considered as a potential photosensitizer in photodynamic therapy of cancer, along with the developed cationic liposomal nanocarrier.

Synthesis and in vitro cytotoxicity evaluation of star-shaped polymethacrylic conjugates with methotrexate or acitretin as potential antipsoriatic prodrugs

Water-soluble polymer-drug conjugates were obtained and analyzed towards their potential use as prodrugs for two hydrophobic antipsoriatic agents, including methotrexate (MTX) and acitretin (AC). The conjugation efficacy of MTX decreased with a decreasing molar ratio of N,N-dimethylaminoethyl methacrylate (DMAEMA) repeating units in the polymethacrylic chains. Cytotoxicity of positively charged (from +5 to +10 mV) nano- and microparticles (3-1500 nm in DMEM at 37 °C) were estimated by in vitro MTT and Annexin-V apoptosis assays on Me45, NHDF, HaCaT and BEAS-2B cell lines. Further, cell cycle analysis revealed arrest in G0/G1 phase in melanoma cells, while neither apoptosis induction nor cell cycle arrest occurred in normal epidermal and epithelial cells. Tested conjugates displayed a novel cytostatic effect in Me45 cells and a pro-apoptotic effect in HaCaT cells. Epithelial BEAS-2B cells were the most sensitive to the tested conjugates and responded via induction of necrosis. Cell line models allowed for characterization of the biologically relevant potential action of pro-drugs. Additionally, a skin in vitro evaluation assay provided the first known evidence of side-effect reduction with pro-drug use. Histological examinations confirmed the lack of negative effects of conjugates on the skin and showed no irritating properties.

Nanocarriers in photodynamic therapy-in vitro and in vivo studies

Photodynamic therapy (PDT) is a minimally invasive technique which has proven to be successful in the treatment of several types of tumors. This relatively simple method exploits three inseparable elements: phototoxic compound (photosensitizer [PS]), light source, and oxygen. Upon irradiation by light with specified wavelength, PS generates reactive oxygen species, which starts the cascade of reactions leading to cell death. The positive therapeutic outcome of PDT may be limited due to several aspects, including low water solubility of PSs, hampering their effective administration and blood circulation, as well as low tumor specificity, inefficient cellular uptake and activation energies requiring prolonged illumination times. One of the promising approaches to overcome these obstacles involves the use of carrier systems modulating pharmacokinetics and pharmacodynamics of the PSs. In the present review, we summarized current in vitro and in vivo studies regarding the use of nanoparticles as potential delivery devices for PSs to enhance their cellular uptake and cytotoxic properties, and thus-the therapeutic outcome of PDT. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Photodynamic therapy using zinc phthalocyanine with low dose of diode laser combined with doxorubicin is a synergistic combination therapy for human SK-MEL-3 melanoma cells

Chemotherapy is a generally used anticancer strategy for melanoma and it may have improved outcomes in combination with other approaches. One such strategy is photodynamic therapy (PDT), where a photosensitizer (PS) generates reactive oxygen species (ROS) after illumination of target cells. Interestingly, in low doses and high doses of light sources, special cellular responses can be induced. Regarding this fact, in this study, the combination of zinc phthalocyanine (ZnPc)-PDT and Doxorubicin (DOX) was applied at low and high dose of diode laser to treat SK-MEL-3 cells. Cytotoxic effects were determined by MTT assay for assessment synergistic effects were estimated by calculation of Combination Index (CI); that synergistic effects were observed in most groups. In low dose of laser irradiation higher synergism effects were observed. Significant changes of ROS were not observed with combinations, but autophagy, subG1 and G2/M phase cell cycle arrest, decreased cell migration ability and apoptosis induction were significantly increased compared to either treatment alone. The expression of caspase-8, -9, -3 and Bcl-2 genes revealed caspase-dependent apoptosis in all groups. Moreover, ZnPc-PDT and chemo-PDT down-regulated the expression of MMP-9 and Vimentin genes that impaired cell migration. In conclusion, it can be suggested that pre-treatment with ZnPc-PDT has high effects to sensitize SK-MEL-3 cells to DOX, in particular with low dose of diode laser.

Folate-mediated and pH-responsive chidamide-bound micelles encapsulating photosensitizers for tumor-targeting photodynamic therapy

Background: Nonspecific tumor targeting, potential relapse and metastasis of tumor after treatment are the main barriers in clinical photodynamic therapy (PDT) for cancer, hence, inhibiting relapse and metastasis of tumor is significant issues in clinic. Purpose: In this work, chidamide as a histone deacetylases inhibitor (HADCi) was bound onto a pH-responsive block polymer folate polyethylene glycol-b-poly(aspartic acid) (PEG-b-PAsp) grafted folate (FA-PEG-b-PAsp) to obtain the block polymer folate polyethylene glycol-b-poly(asparaginyl-chidamide) (FA-PEG-b-PAsp-chidamide, FPPC) as multimodal tumor-targeting drug-delivery carrier to inhibiting tumor cell proliferation and tumor metastasis in mice. Methods: Model photosensitizer pyropheophorbide-a (Pha) was encapsulated by FPPC in PBS to form the polymer micelles Pha@FPPC [folate polyethylene glycol-b-poly(asparaginyl-chidamide) micelles encapsulating Pha]. Pha@FPPC was characterized by transmission electron microscope and dynamic light scattering; also, antitumor activity in vivo and in vitro were investigated by determination of cellular ROS level, detection of cell apoptosis and cell cycle arrest, PDT antitumor activity in vivo and histological analysis. Results: With favorable and stable sphere morphology under transmission electron microscope (TEM) (~93.0 nm), Pha@FPPC greatly enhanced the cellular uptake due to its folate-mediated effective endocytosis by mouse melanoma B16-F10 cells and the yield of ROS in tumor cells induced by PDT, and mainly caused necrocytosis and blocked cell growth cycle not only in G2 phase but also in G1/G0 phase after PDT. Pha@FPPC exhibited lower dark cytotoxicity in vitro and a better therapeutic index because of its higher dark cytotoxicity/photocytotoxicity ratio. Moreover, Pha@FPPC not only significantly inhibited the growth of implanted tumor and prolonged the survival time of melanoma-bearing mice due to both its folate-mediated tumor-targeting and selectively accumulation at tumor site by EPR (enhanced permeability and retention)effect as micelle nanoparticles but also remarkably prevented pulmonary metastasis of mice melanoma after PDT compared to free Pha, demonstrating its dual antitumor characteristics of PDT and HDACi. Conclusion: As a folate-mediated and acid-activated chidamide-grafted drug-delivery carrier, FPPC may have great potential to inhibit tumor metastasis in clinical photodynamic treatment for cancer because of its effective and multimodal tumor-targeting performance as photosensitizer vehicle.