Therapeutic role of vanillin receptors in cancer

Natural products play significant roles in the development of novel drugs. One of such compounds is vanillin - a natural substance commonly used in food. Anticancer potential of the substance is continually encouraging researchers to conduct further investigations. A rising number of publications describe the role of 4-hydroxy-3-methoxybenzaldehyde (vanillin) in the process of inhibiting tumor growth. Four vanilloid receptors play significant roles in the response of cancer cells to the natural compound. Each of these proteins can be individually affected by vanillin; thus, the substance either leads to inhibition of the cell proliferation or increases the Ca2+ level. The TRPV1, a non-selective cation channel permeable to calcium, acts on cancer development and progression. Thus, vanilloid receptors have the potential to become the target for therapeutical research. Moreover, selective inhibitors of the receptor have proved their efficacy in vitro. CK2α is an antiapoptotic, cancer-sustaining protein and, therefore, the inhibitor of apoptosis. Thus, drugs that exhibit allosteric and ATP-competitive inhibition of the protein might be crucial for cancer therapy. CAMK4 is a protein kinase expression associated with a wide array of cancers. Also, MARK4 is another kinase responsible for the stability of microtubules, overexpressed in many cancer types. Studies concerning this protein revealed that microtubule impairment might be a cancer therapy direction. This review aims to demonstrate the crucial role of described vanilloid receptors in inhibiting the proliferation of cancer cells and to prove the usefulness of using vanillin and its derivatives in the process of drug design.

Dualistic role of autophagy in cancer progression

This review aims to characterize the dualistic role of autophagy in both the suppression and propagation of carcinogenesis. The process of autophagy is responsible for maintaining the delicate balance between the survival and death of a cell, and in the past years it has been studied profoundly. It has been proven that the role of autophagy in maintaining genomic and structural integrity can lead to the suppression of carcinogenesis in its early stages. However, once carcinogenesis has occurred, the process of autophagy may contribute to the survival of tumor cells and, consequently, lead to tumor progression. Additionally, autophagy can modulate the response of the tumor cells to therapy, leading to radiotherapy and chemotherapy resistance or reduced susceptibility to anticancer drugs that propagate autophagy-related cell death. Although the role and course of autophagy are not yet fully known, the essence of it seems to be within our grasp. We have observed the identification of an increasing number of autophagy-related genes (ATG). Therefore, more research concerning its molecular course and potential applications in cancer treatment and prevention needs to be conducted.

Atorvastatin Modulates the Efficacy of Electroporation and Calcium Electrochemotherapy

Electroporation is influenced by the features of the targeted cell membranes, e.g., the cholesterol content and the surface tension of the membrane. The latter is eventually affected by the organization of actin fibers. Atorvastatin is a statin known to influence both the cholesterol content and the organization of actin. This work analyzes the effects of the latter on the efficacy of electroporation of cancer cells. In addition, herein, electroporation was combined with calcium chloride (CaEP) to assess as well the effects of the statin on the efficacy of electrochemotherapy. Cholesterol-rich cell lines MDA-MB231, DU 145, and A375 underwent (1) 48 h preincubation or (2) direct treatment with 50 nM atorvastatin. We studied the impact of the statin on cholesterol and actin fiber organization and analyzed the cells’ membrane permeability. The viability of cells subjected to PEF (pulsed electric field) treatments and CaEP with 5 mM CaCl₂ was examined. Finally, to assess the safety of the therapy, we analyzed the N-and E-cadherin localization using confocal laser microscopy. The results of our investigation revealed that depending on the cell line, atorvastatin preincubation decreases the total cholesterol in the steroidogenic cells and induces reorganization of actin nearby the cell membrane. Under low voltage PEFs, actin reorganization is responsible for the increase in the electroporation threshold. However, when subject to high voltage PEF, the lipid composition of the cell membrane becomes the regulatory factor. Namely, preincubation with atorvastatin reduces the cytotoxic effect of low voltage pulses and enhances the cytotoxicity and cellular changes induced by high voltage pulses. The study confirms that the surface tension regulates of membrane permeability under low voltage PEF treatment. Accordingly, to reduce the unfavorable effects of preincubation with atorvastatin, electroporation of steroidogenic cells should be performed at high voltage and combined with a calcium supply.

Effects of high-frequency nanosecond pulses on prostate cancer cells

Electroporation with pulsed electric fields show a potential to be applied as an experimental focal therapy of tumors. Sub-microsecond regime of electric pulses displays unique electrophysical features operative in cells and membranes. Recently, MHz compression of nanosecond pulses electric fields (nsPEFs) bursts proved to enhance the effectiveness of the therapy. High morbidity of prostate cancer (PCa) and risk of overtreatment associated with this malignancy call for new minimal-invasive treatment alternative. Herein we present the in vitro study for developing applications based on this new technology. In this study, we used flow cytometric analysis, cell viability assay, caspase activity analysis, wound healing assay, confocal microscopy study, and immunofluorescence to investigate the biological effect of high-frequency nsPEFs on PCa cells. Our results show that high-frequency nsPEFs induces the permeabilization and cell death of PCa cells. The cytotoxicity is significantly enhanced in MHz compression of pulses and with the presence of extracellular Ca²⁺. High-frequency nsPEFs trigger changes in PCa cells' cytoskeleton and their mobility. The presented data show a therapeutic potential of high-frequency nsPEFs in a PCa setting. The sub-microsecond regime of pulses can potentially be applied in nanosecond electroporation protocols for PCa treatment.

Natural polymers in photodynamic therapy and diagnosis

Natural polymers have been commonly applied in medicine and pharmacy. Their primary function is to enhance drug delivery, tissue regeneration or wound healing, and diagnostics. Natural polymers appear promising for photodynamic protocols, including photodiagnosis (PDD) and photodynamic therapy (PDT). Currently, the most challenging issue with natural polymers is to appropriately select the most effective material regarding the type of cancer treated. The technological achievements enable functionalization of natural polymers by specific antibodies, or enhancement using fluorescent or quantum dot markers for diagnostic applications. This review will discuss the types and properties of natural polymers and available applications of PDD and PDT which seem to be promising in cancer treatment. Treatment of neoplastic diseases is still a challenge for both physicians and scientists, so the search for alternative methods of treatment and diagnosis based on natural materials is relevant.

Antiradical Properties of N-Oxide Surfactants-Two in One

Surfactants are molecules that lower surface or interfacial tension, and thus they are broadly used as detergents, wetting agents, emulsifiers, foaming agents, or dispersants. However, for modern applications, substances that can perform more than one function are desired. In this study we evaluated antioxidant properties of two homological series of N-oxide surfactants: monocephalic 3-(alkanoylamino)propyldimethylamine-N-oxides and dicephalic N,N-bis[3,3′-(dimethylamino)propyl]alkylamide di-N-oxides. Their antiradical properties were tested against stable radicals using electron paramagnetic resonance (EPR) and UV-vis spectroscopy. The experimental investigation was supported by theoretical density functional theory (DFT) and ab initio modeling of the X–H bonds dissociation enthalpies, ionization potentials, and Gibbs free energies for radical scavenging reactions. The evaluation was supplemented with a study of biological activity. We found that the mono- and di-N-oxides are capable of scavenging reactive radicals; however, the dicephalic surfactants are more efficient than their linear analogues.

New therapeutic strategy: Personalization of pancreatic cancer treatment-irreversible electroporation (IRE), electrochemotherapy (ECT) and calcium electroporation (CaEP) - A pilot preclinical study

In this study, irreversible electroporation (IRE), electrochemotherapy (ECT), and calcium electroporation (CaEP) techniques were investigated as new strategies for human pancreatic cancer. Qualification of the patients, best "therapeutic moment" for each patient, safety, and complications after procedures were examined. In this pilot study were included 13 patients in this study, which were operated on in different pancreatic cancer stages. Patients underwent IRE or ECT with intravenous admission of cisplatin or electroporation with calcium intratumoral administration. The IRE procedure was safe for the patients. Medium overall survival for IRE, IRE + CTH, and IRE + CaCl₂ was respectively: 16, 29.5, and 19 months comparing to 10 months in control chemotherapy (CTH) group. Thus, IRE, ECT, and CaEP can be effective strategies for pancreatic cancer treatment.

Effects of calcium electroporation, electrochemotherapy, and irreversible electroporation on quality of life and progression-free survival in patients with pancreatic cancer: IREC clinical study

BACKGROUND

According to the National Cancer Registry, 3486 people (1744 men and 1742 women) were diagnosed with pancreatic adenocarcinoma in Poland in 2018, resulting in 4908 deaths (2396 men and 2512 women). The only chance of successful treatment is through surgical resection, which is possible in only 20-30% of patients (stage I, II and some stage III cases).The remaining 70-80% of patients are those with stage III and IV disease, for whom resection is not possible. Mean survival in these patients is approx. 10.4 months (stage III). In the recent decade, an innovative method called electroporation, which involves destabilization of the cell membrane, has been established. This process can be reversible (RE) or irreversible (IRE), and leads to cell death. The ability to change membrane permeability has led to the development of novel methods involving electrochemotherapy (ECT) and calcium electroporation (CaEP) to treat solid tumors.

OBJECTIVES

In this study, both ECT and CaEP will be used to treat pancreatic cancer patients with poor prognosis. For each patient, the best "therapeutic moment" for the procedure will be selected based on the therapeutic protocol.

MATERIAL AND METHODS

Patients will receive reversible and irreversible electroporation (control arm-group A), CaEP (active arm-group B), or ECT with intravenous and intratumoral administration of bleomycin (active arm-group C) randomized 1:1:1.

RESULTS

The primary endpoints will be progression-free survival (PFS) and patients' quality of life (QOL) assessed using the EORTC-PAN 26 scale. Secondary endpoints will be patient overall survival (OS), body weight, pain level, and levels of biomarkers such as Ca 19-9.

CONCLUSION

The Irreversible Electroporation, ELectrochemotherapy and Calcium electroporation (IREC) study is necessary to examine the safety and efficiency of irreversible electroporation, electrochemotherapy and calcium electroporation in pancreatic cancer treatment.

Polymeric Nanocarriers with Luminescent Colloidal Nanoplatelets as Hydrophilic and Non-Toxic Two-Photon Bioimaging Agents

Introduction

Semiconductor nanoplatelets (NPLs) are promising materials for nonlinear optical microscopy since they feature good two-photon absorption (TPA) properties, narrow photoluminescence spectra and high quantum yields of luminescence. Nevertheless, the use of semiconductor NPLs is inevitably connected with concerns about heavy metal ion toxicity and their intrinsically hydrophobic character.

Methods

Our contribution focuses on the design and engineering of coloidal bionanomaterial consisting of two-dimensional highly luminescent CdSe semiconductor NPLs loaded into spherical and homogeneous polymeric nanocarriers (NCs) based on poly(ethylene oxide) and poly(propylene oxide) block co-polymer. The biocompatibility and usefulness of the NPLs-loaded polymeric NCs in two-photon induced bioimaging was demonstrated invitroby cytotoxicity and two-photon microscopic studies using eukaryotic (normal fibroblasts and cancer ovarian) cells.

Results

The encapsulated NPLs maintain their intensive and spectrally narrow photoluminescence, as well as preserve good TPA properties, while the surrounding polymer shell imparts hydrophilic character and non-toxicity towards eukaryotic cells. Specifically, TPA cross-sections of the colloidal NCs loaded with NPLs show large values reaching up to 2.0 × 10⁸ GM, with simultaneously two-photon brightness reaching 2.2 × 10⁷ GM at 870 nm. MTT proliferation assay performed on cell lines treated with encapsulated NPLs revealed at least 70% viability of normal human gingival fibroblast (HGF) and cancer ovarian (MDAH-2774) cells, while the results of multiphoton imaging of murine (L-929) fibroblasts suggest that the encapsulated NPLs are capable of labelling the target cells enabling their visualization.

Conclusion

As a result, we obtained water dispersible and temporally stable hydrophilic NPLs-loaded NCs that offer excellent, both one- and two-photon excited fluorescence preserving optical properties of the raw hydrophobic and colloidal NPLs. The biological responses upon eukaryotic cells indicate that the encapsulation process protects cells from the toxic influence of cadmium simultaneously preserving the unique multiphoton properties of the active cargo which opens a promising perspective for its application in multiphoton cancer bioimaging excited at the “optical transmission window” of biological tissues in near-infrared range.

Modulation of Blood-Brain Barrier Permeability by Activating Adenosine A2 Receptors in Oncological Treatment

The blood–brain barrier (BBB) plays an important protective role in the central nervous system and maintains its homeostasis. It regulates transport into brain tissue and protects neurons against the toxic effects of substances circulating in the blood. However, in the case of neurological diseases or primary brain tumors, i.e., gliomas, the higher permeability of the blood-derived substances in the brain tissue is necessary. Currently applied methods of treatment for the primary brain neoplasms include surgical removal of the tumor, radiation therapy, and chemotherapy. Despite the abovementioned treatment methods, the prognosis of primary brain tumors remains bad. Moreover, chemotherapy options seem to be limited due to low drug penetration into the cancerous tissue. Modulation of the blood–brain barrier permeability may contribute to an increase in the concentration of the drug in the CNS and thus increase the effectiveness of therapy. Interestingly, endothelial cells in cerebral vessels are characterized by the presence of adenosine 2A receptors (A2AR). It has been shown that substances affecting these receptors regulate the permeability of the BBB. The mechanism of increasing the BBB permeability by A2AR agonists is the actin-cytoskeletal reorganization and acting on the tight junctions. In this case, the A2AR seems to be a promising therapy target. This article aims to assess the possibility of increasing the BBB permeability through A2AR agonists to increase the effectiveness of chemotherapy and to improve the results of cancer therapy.

Mechanisms of curcumin-based photodynamic therapy and its effects in combination with electroporation: An in vitro and molecular dynamics study

Photodynamic therapy (PDT) and electrochemotherapy (ECT) are two methods designed to enhance the anticancer potential of various drugs. Various clinical trials proved the efficacy of both ECT and PDT in melanoma treatment. Curcumin is a natural polyphenolic compound with high anticancer potential against melanoma due to its light absorption properties and toxicity towards cancer cells; however, high reactivity and amphipathic structure of curcumin are limiting its utility. This study aimed to propose the most effective protocol for antimelanoma combination of both therapies (PDT and ECT) in the context of curcumin. The in vitro studies were carried on melanotic melanoma (A375), amelanotic melanoma (C32) and fibroblast (HGF) cell lines. In molecular dynamics studies curcumin presented the single-layer localization in the water-membrane interphase. Further, the mass spectrometry studies exposed that during the PDT treatment curcumin is degraded to vanillin, feruloylmethane, and ferulic acid. Instant ECT with curcumin followed by PDT is the most efficient approach due to its selective genotoxicity towards malignant cells. The metabolic activity of fibroblasts decreased, however, at the same time the fragmentation of DNA did not occur. Additionally, instant PDT with curcumin followed by ECT after 3 h of incubation was a therapy selective towards melanotic melanoma.

Modifications of Plasma Membrane Organization in Cancer Cells for Targeted Therapy

Modifications of the composition or organization of the cancer cell membrane seem to be a promising targeted therapy. This approach can significantly enhance drug uptake or intensify the response of cancer cells to chemotherapeutics. There are several methods enabling lipid bilayer modifications, e.g., pharmacological, physical, and mechanical. It is crucial to keep in mind the significance of drug resistance phenomenon, ion channel and specific receptor impact, and lipid bilayer organization in planning the cell membrane-targeted treatment. In this review, strategies based on cell membrane modulation or reorganization are presented as an alternative tool for future therapeutic protocols.

A Review on the Adaption of Alginate-Gelatin Hydrogels for 3D Cultures and Bioprinting

Sustaining the vital functions of cells outside the organism requires strictly defined parameters. In order to ensure their optimal growth and development, it is necessary to provide a range of nutrients and regulators. Hydrogels are excellent materials for 3D in vitro cell cultures. Their ability to retain large amounts of liquid, as well as their biocompatibility, soft structures, and mechanical properties similar to these of living tissues, provide appropriate microenvironments that mimic extracellular matrix functions. The wide range of natural and synthetic polymeric materials, as well as the simplicity of their physico-chemical modification, allow the mechanical properties to be adjusted for different requirements. Sodium alginate-based hydrogel is a frequently used material for cell culture. The lack of cell-interactive properties makes this polysaccharide the most often applied in combination with other materials, including gelatin. The combination of both materials increases their biological activity and improves their material properties, making this combination a frequently used material in 3D printing technology. The use of hydrogels as inks in 3D printing allows the accurate manufacturing of scaffolds with complex shapes and geometries. The aim of this paper is to provide an overview of the materials used for 3D cell cultures, which are mainly alginate-gelatin hydrogels, including their properties and potential applications.

Testing Lab-on-a-Chip Technology for Culturing Human Melanoma Cells under Simulated Microgravity

The dynamic development of the space industry makes space flights more accessible and opens up new opportunities for biological research to better understand cell physiology under real microgravity. Whereas specialized studies in space remain out of our reach, preliminary experiments can be performed on Earth under simulated microgravity (sµg). Based on this concept, we used a 3D-clinostat (3D-C) to analyze the effect of short exposure to sµg on human keratinocytes HaCaT and melanoma cells A375 cultured on all-glass Lab-on-a-Chip (LOC). Our preliminary studies included viability evaluation, mitochondrial and caspase activity, and proliferation assay, enabling us to determine the effect of sµg on human cells. By comparing the results concerning cells cultured on LOCs and standard culture dishes, we were able to confirm the biocompatibility of all-glass LOCs and their potential application in microgravity research on selected human cell lines. Our studies revealed that HaCaT and A375 cells are susceptible to simulated microgravity; however, we observed an increased caspase activity and a decrease of proliferation in cancer cells cultured on LOCs in comparison to standard cell cultures. These results are an excellent basis to conduct further research on the possible application of LOCs systems in cancer research in space.

Investigating the photodynamic efficacy of chlorin e6 by millisecond pulses in metastatic melanoma cells

Melanoma is considered the most aggressive type of skin cancer, still without effective treatment. Thus, alternative therapeutic methods are still in demand, and electroporation-supported photodynamic therapy (EP-PDT) of cancer cells seems a promising approach. New developments in EP-PDT aim at enhanced tumor selectivity and biocompatibility by applying a second-generation photosensitizer, i.e., Chlorin e6 (Ce6). We have verified the improved photodynamic effect of Ce6 on skin cancer melanoma (Me45) cells and control (CHO-K1) cells. In this study, we applied 1 or 5 pulses of 10 ms duration and assessed the EP-PDT effect with a variety of tests, such as singlet oxygen scavenger (ABMDMA) photooxidation, oxidoreductive potential measurements, kinetic measurements with fluorescent microscopy, photosensitizer uptake studies, lipid peroxidation level, and actin fibers organization. The optimization of photosensitizer uptake as a function of temperature was also performed. Our results indicated efficient Ce6 delivery into Me45 cells and good photodynamic efficiency enhanced by the electroporation of cancer cells.

Electrochemotherapy with Calcium Chloride and 17β-Estradiol Modulated Viability and Apoptosis Pathway in Human Ovarian Cancer

Estrogens (Es) play a significant role in the carcinogenesis and progression of ovarian malignancies. Depending on the concentration, Es may have a protective or toxic effect on cells. Moreover, they can directly or indirectly affect the activity of membrane ion channels. In the presented study, we investigated in vitro the effectiveness of the ovarian cancer cells (MDAH-2774) pre-incubation with 17β-estradiol (E2; 10 µM) in the conventional chemotherapy (CT) and electrochemotherapy (ECT) with cisplatin or calcium chloride. We used three different protocols of electroporation including microseconds (µsEP) and nanoseconds (nsEP) range. The cytotoxic effect of the applied treatment was examined by the MTT assay. We used fluorescent staining and holotomographic imaging to observe morphological changes. The immunocytochemical staining evaluated the expression of the caspase-12. The electroporation process's effectiveness was analyzed by a flow cytometer using the Yo-Pro™-1 dye absorption assay. We found that pre-incubation of ovarian cancer cells with 17β-estradiol may effectively enhance the chemo- and electrochemotherapy with cisplatin and calcium chloride. At the same time, estradiol reduced the effectiveness of electroporation, which may indicate that the mechanism of increasing the effectiveness of ECT by E2 is not related to the change of cell membrane permeability.

In Vitro Study of Calcium Microsecond Electroporation of Prostate Adenocarcinoma Cells

Electroporation, applied as a non-thermal ablation method has proven to be effective for focal prostate treatment. In this study, we performed pre-clinical research, which aims at exploring the specific impact of this so-called calcium electroporation on prostate cancer. First, in an in-vitro study of DU 145 cell lines, microsecond electroporation (μsEP) parameters were optimized. We determined hence the voltage that provides both high permeability and viability of these prostate cancer cells. Subsequently, we compared the effect of μsEP on cells' viability with and without calcium administration. For high-voltage pulses, the cell death's mechanism was evaluated using flow-cytometry and confocal laser microscopy. For lower-voltage pulses, the influence of electroporation on prostate cancer cell mobility was studied using scratch assays. Additionally, we applied calcium-binding fluorescence dye (Fluo-8) to observe the calcium uptake dynamic with the fluorescence microscopy. Moreover, the molecular dynamics simulation visualized the process of calcium ions inflow during μsEP. According to our results calcium electroporation significantly decreases the cells viability by promoting apoptosis. Furthermore, our data shows that the application of pulsed electric fields disassembles the actin cytoskeleton and influences the prostate cancer cells' mobility.

Bioluminescence as a sensitive electroporation indicator in sub-microsecond and microsecond range of electrical pulses

The cell membrane permeabilization in electroporation studies is usually quantified using fluorescent markers such as propidium iodide (PI) or YO-PRO, while Chinese Hamster Ovary cell line frequently serves as a model. In this work, as an alternative, we propose a sensitive methodology for detection and analysis of electroporation phenomenon based on bioluminescence. Luminescent mice myeloma SP2/0 cells (transfected using Luciferase-pcDNA3 plasmid) were used as a cell model. Electroporation has been studied using the 0.1-5 μs × 250 and 100 μs × 1-8 pulsing protocols in 1-2.5 kV/cm PEF range. It was shown that the bioluminescence response is dependent on the cell permeabilization state and can be effectively used to detect even weak permeabilization. During saturated permeabilization the methodology accurately predicts the losses of cell viability due to irreversible electroporation. The results have been superpositioned with permeabilization and pore resealing (1 h post-treatment) data using PI. Also, the viability of the cells was evaluated. Lastly, the SP2/0 tumors have been developed in BALB/C mice and the methodology has been tested in vivo using electrochemotherapy with bleomycin.

Effects of curcumin based PDT on the viability and the organization of actin in melanotic (A375) and amelanotic melanoma (C32) - in vitro studies

Curcumin is a turmeric, antioxidative compound, well-known of its anti-cancer properties. Nowadays more and more effort is made in the field of enhancing the efficiency of the anticancer therapies. Combining the photoactive properties of curcumin with the superficial localization of melanoma and photodynamic therapy (PDT) seems to be a promising treatment method. The research focused on the evaluation of the curcumin effectiveness as an anticancer therapeutic agent in the in vitro treatment of melanotic (A375) and amelanotic (C32) melanoma cell lines. Keratinocytes (HaCat) and fibroblasts (HGF) were used to assess the impact of the therapy on the skin tissue. The aim of the study was to investigate the cell death after exposure to light irradiation after preincubation with curcumin. Additionaly the authors analized the interactions between curcumin and the actin cytoskeleton. The cytotoxic effect initiated by curcumin and increased by irradiation confirm the usefulness of the flavonoid in the PDT approach. Depending on curcumin concentration and incubation time, melanoma cells survival rate ranged from: 93.68 % (C32 cell line, 10 μM, 24 h) and 83.47 % (A375 cell line, 10 μM, 24 h) to 8.98 % (C32 cell line, 50 μM, 48 h) and 12.42 % (A375 cell line, 50 μM, 48 h). Moreover, photodynamic therapy with curcumin increased the number of apoptotic and necrotic cells in comparison to incubation with curcumin without irradiation. The study demonstrated that PDT induced caspase-3 overexpression and DNA cleavage in the studied cell lines. The cells revealed decreased proliferation after the therapy due to the actin cytoskeleton rearrangement. Although effective, the therapy remains not selective towards melanoma cells.

Abstract A08: The effect of irradiation with curcumin as a possible form of amelanotic melanoma treatment

Nowadays new medicines are being sought to effectively fight against melanoma. Metabolites of natural compounds have been used for antimelanoma therapy for a long time, but in recent years, new active substances of natural origin have been discovered with proven effects that interfere with the metabolism of tumor cells. The most interesting are compounds exhibiting low toxicity against normal cells, and selective cytotoxicity against cancer cells. One of these compounds is curcumin—a component of turmeric. Curcumin has immunomodulatory, anti-inflammatory, anticancer effects, affects the phase II enzymes and is a potent photosensitizer, thus showing strong potential for use in oncotherapy.

Curcumin has been investigated as a potential photosensitizer (PS) in anticancer photodynamic therapy (PDT). The phototoxic effect of curcumin is dependent on proper formulations of the compound because of the lipophilic nature of the molecule and the extremely low water solubility at physiologic conditions. In the present study, the combination of curcumin was investigated in PDT using human melanoma amelanotic cell line (C32) and normal human fibroblasts from primary culture as control cells. The cells were maintained in culture and then treated with curcumin at concentrations of 5-50 μM for 2, 24 and 48. Then cells were irradiated with blue light (20 J/cm2) for 5 minutes and incubated for 24 hours. The efficacy of photodynamic effect was evaluated by viability assay (MTT). Additionally, cell death assay and cellular reactive oxygen species (ROS) assay were assessed. The intracellular distribution of curcumin after different time of incubation was visualized by CLSM method.

The results suggest that curcumin may be a potent alternative to commonly used cytostatics. Depending on the curcumin concentration, the cell survival ranged from 18.95% of control cells after incubation with 50 μM curcumin to 0.91% after PDT. It has been shown that PDT with curcumin can increase oxidative stress and number of apoptotic and necrotic cells in comparison to incubation with curcumin without irradiation. The reduced and selective anticancer activity as compared to other drugs can be the basis for the use of curcumin also in complementary treatment of amelanotic melanoma.

This study has revealed for the first time that PDT with curcumin appears to represent an efficient alternative for the treatment of amelanotic melanoma through the in situ application of the photosensitizer followed by irradiation of the photosensitizer-loaded area. Thus, the proposed protocol seems to be promising in the amelanotic melanoma, which is extremely resistant to standard chemo- and radiotherapy.

Citation Format: Stanislaw Kwiatkowski, Dawid Przystupski, Krzysztof Kotowski, Agata Gorska, Weronika Bartosik, Aleksander Kielbik, Jolanta Saczko, Julita Kulbacka. The effect of irradiation with curcumin as a possible form of amelanotic melanoma treatment [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A08.

Lipid composition of the cancer cell membrane

Cancer cell possesses numerous adaptations to resist the immune system response and chemotherapy. One of the most significant properties of the neoplastic cells is the altered lipid metabolism, and consequently, the abnormal cell membrane composition. Like in the case of phosphatidylcholine, these changes result in the modulation of certain enzymes and accumulation of energetic material, which could be used for a higher proliferation rate. The changes are so prominent, that some lipids, such as phosphatidylserines, could even be considered as the cancer biomarkers. Additionally, some changes of biophysical properties of cell membranes lead to the higher resistance to chemotherapy, and finally to the disturbances in signalling pathways. Namely, the increased levels of certain lipids, like for instance phosphatidylserine, lead to the attenuation of the immune system response. Also, changes in lipid saturation prevent the cells from demanding conditions of the microenvironment. Particularly interesting is the significance of cell membrane cholesterol content in the modulation of metastasis. This review paper discusses the roles of each lipid type in cancer physiology. The review combined theoretical data with clinical studies to show novel therapeutic options concerning the modulation of cell membranes in oncology.

Effect of diallyl disulfide and garlic oil on different human astrocytoma cell lines

Gliomas are a group of malignant brain tumors. Despite significant efforts to optimize treatment options for patients with high-grade glioma, the prognosis of the overwhelming majority of patients remain poor. This bleak prognosis despite treatment of the glioma, is partly due to the tendency of therapeutics to diffusely penetrate into the neighboring brain tissues, but also due to the innate resistance of these tumors to chemotherapy and radiation. Garlic contains water-soluble and oil-soluble sulfur compounds. The oil-soluble compounds, including diallyl sulfide, diallyl disulfide (DADS), diallyl trisulfide and ajoene, are more effective potential anti-cancer treatments than the water-soluble compounds. There are several studies examining the effects of oil-soluble compounds on various types of cancer cells, although, to the best of our knowledge, there are no studies examining the effects of these compounds on glioma cells. The aim of the present study was to investigate the potential anti-glioma properties of DAD and garlic oil on proliferation and induction of apoptosis in four different types of glioma cell lines representative of different grades of the disease. The results showed that garlic oil exhibits favorable anti-cancer potential towards gliomas of various degrees of differentiation.

Electroporation-Based Treatments in Urology

The observation that an application of a pulsed electric field (PEF) resulted in an increased permeability of the cell membrane has led to the discovery of the phenomenon called electroporation (EP). Depending on the parameters of the electric current and cell features, electroporation can be either reversible or irreversible. The irreversible electroporation (IRE) found its use in urology as a non-thermal ablative method of prostate and renal cancer. As its mechanism is based on the permeabilization of cell membrane phospholipids, IRE (as well as other treatments based on EP) provides selectivity sparing extracellular proteins and matrix. Reversible EP enables the transfer of genes, drugs, and small exogenous proteins. In clinical practice, reversible EP can locally increase the uptake of cytotoxic drugs such as cisplatin and bleomycin. This approach is known as electrochemotherapy (ECT). Few in vivo and in vitro trials of ECT have been performed on urological cancers. EP provides the possibility of transmission of genes across the cell membrane. As the protocols of gene electrotransfer (GET) over the last few years have improved, EP has become a well-known technique for non-viral cell transfection. GET involves DNA transfection directly to the cancer or the host skin and muscle tissue. Among urological cancers, the GET of several plasmids encoding prostate cancer antigens has been investigated in clinical trials. This review brings into discussion the underlying mechanism of EP and an overview of the latest progress and development perspectives of EP-based treatments in urology.

Apoptosis as the main type of cell death induced by calcium electroporation in rhabdomyosarcoma cells

Calcium electroporation (CaEP) has been previously reported as an effective method of rhabdomyosarcoma cells reduction. CaEP causes temporary cell membrane permeabilization with simultaneous calcium ions influx. A rapid influx of calcium ions leads to mitochondrial overload by Ca²⁺, loss of mitochondrial membrane potential causing cytochrome c release, caspase cascade activation and, as a consequence, cell death. This study was conducted on two cell lines: normal muscle cells (C2C12) and rhabdomyosarcoma cells (RD), which showed different cellular responses to CaEP. Our study defined apoptosis as the main cell death type occurring after CaEP in RD cells. Increased activity of caspase 3/7, Parp-1 and cleaved Parp-1 were proven in the case of RD cells. RD cells compartment rearrangement was observed in the time-lapse by holotomographic microscopy (HTM). C2C12 cells were less sensitive to electroporation and increased Ca²⁺ concentration, and viability was maintained at the level of control cells, only slight changes in pro-apoptotic factors were observed. The results reveal CaEP as a promising therapeutic approach in cancers which develop from muscle tissue.

The effect of dental gel formulation on human primary fibroblasts - an in vitro study

INTRODUCTION

In ordinary dental practice, the dentist often meets with patients suffering from ulcers, aphtha with edema, bleeding gums, bothersome burning, and dry mouth. These are prosthetic, orthodontic patients, after surgery, in various age ranges. Protefix® gel is a soothing and regenerating preparation aimed at patients with mucosal problems. The aim of our study was to evaluate the protective properties and the safety of Protefix® gel application after dental procedures in vitro.

MATERIAL AND METHODS

Human gingival fibroblasts (HGFs) were isolated from normal gingival tissues, cultured to full monolayer and exposed to Protefix® gel in the concentration from 1 to 100%. The viability of cells was examined by MTT assays. Cell migration as a response of treated cells was assessed. The expression of collagen III was estimated by immunocytochemistry after 20 minutes or 24 hours incubation with Protefix® gel.

RESULTS

The obtained results indicated that the verified gel significantly stimulated fibroblasts' proliferation, and mitochondrial activity determined by MTT assay increased almost two-fold for lower gel concentrations. The immunohistochemical detection of collagen III revealed an increased expression after incubation with 5% gel.

CONCLUSIONS

The results proved that the gel is safe for cells derived from human gingiva and moreover has regenerative properties, which can be of great importance in the treatment of gingivitis after retraction and surgical procedures, or even ordinary daily injuries of oral cavity.