Ispitivanje mogućnosti korišćenja nanočestica TiO2 kao nosača za ciljanu i kontrolisanu dostavu lekova na bazi kompleksa prelaznih metala

Sinteza i primena kompleksa prelaznih metala u lečenju kancera je predmet istraživanja velikog broja naučnika. Potreba za razvojem novih citostatika proizilazi iz želje da se prevaziđu nedostaci već postojećih, kao što su rezistencija, toksičnost i uzak terapeutski opseg (aktivnost protiv malog broja tipova tumora). Tako se pored kompleksa platine, i dalje najčešće korišćenih citostatika u kliničkoj praksi, razvila čitava serija novih kompleksa redizajniranjem već postojećih izmenom liganada i/ili izmenom centralnog metalnog jona. Posebno su se izdvojili kompleksi rutenijuma zbog manje toksičnosti, aktivnosti na metastazama i tumorima na kojima su dotadašnji citostatici bili neaktivni, a neki od njih su pokazali aktivnost tek kada se ozrače svetlošću odgovarajuće talasne dužine i potencijal za primenu u fotodinamičkoj terapiji. Uprkos razvoju novih generacija citostatika s poboljšanim karakteristikama, kao problem ostaje kontrola postizanja maksimalne koncentracije leka u tumorskom tkivu. Na putu do ciljnog, tumorskog tkiva i ciljnih biomolekula, lek interaguje i s brojnim drugim biomolekulima što za posledicu može imati toksičnost, pojavu rezistencije, inaktivaciju leka i smanjenje njegove efektivne koncentracije na željenom mestu dejstva. Potreba za prevazilaženjem ovog problema dovela je do brzog razvoja nosača za lekove. Njihova uloga je da vežu ili inkapsuliraju lek, nose ga do tumorskog tkiva sprečavajući njegovu interakciju s okolnim biomolekulima i zatim ga otpuste, aktivnim ili pasivnim mehanizmom, u ciljnom tumorskom tkivu. Cilj upotrebe ovakvih sistema je smanjenje štetnog dejstva leka na zdravo tkivo, mogućnost kontrole doziranja leka tj. postizanje njegove optimalne koncentracije u tumorskom tkivu, a samim tim i postizanje veće efikasnosti terapije. Nosači koji se testiraju za mogućnost primene u kontrolisanoj i ciljanoj dostavi medikamenata su uglavnom na bazi organskih i neorganskih nanomaterijala, međutim mali broj njih je u kliničkoj upotrebi (lipozomi i polimerni nanomaterijali). U fazi ispitivanja su mnogobrojni nosači koji reaguju na stimulanse kao što su pH sredine, ultrazvuk, temperatura i svetlost. U novijim istraživanjima veliku pažnju kao nosači za lekove zauzimaju nanočestice TiO2 zbog svoje biokompatibilnosti, fotoaktivnosti, dostupnosti i mogućnosti modifikacije površine.A significantly rising interest in the design and use of metal complexes for cancer treatment is currently observed in the area of scientific inquiry. There has been a growing demand for development and improvement of metal-based compounds used in routine clinical practice in order to overcome disadvantages and limitations such as resistance, toxicity and narrow spectrum of activity (activity against a small number of tumor types). Beside platinum complexes, the leading agents in clinical use, many more metal-based compounds have been synthesized by redesigning the existing chemical structure through ligand substitution and/or central metal ion switching. Among them ruthenium complexes have been investigated as one of the most promising candidates because they shown less toxicity, significant activity against cancer metastases, and activity on tumors that were resistant to a variety of standard chemotherapeutic agents. Moreover, some of them are light sensitive drugs i.e. their functions is triggered once they are activated by light of a specific wavelength which make them promising candidates for photodynamic therapy. Despite fast development of new generation of cytostatics with better characteristics, there are still areas where substantial improvements need to be made. One such area is achievement of a maximum concentration of the drug on tumor site. Once the drug enters the systemic circulation, it could face a number of challenges. Drug could react with nontarget biomolecules on its way to target biomolecules in tumor tissue which could cause severe side effects such as toxicity, resistance, inactivation of the drug and reduction of its effective concentration at the target tumor site. One way to solve these problems is the development of drug delivery systems which consist of drug and drug carrier. Role of drug carriers is to bind or encapsulate the drug, prevent its interaction with non-target biomolecules, to carry the drug to the target tumor tissue and then release it with active or passive mechanism. The main advantages of using drug delivery systems are reduction of side effects of drug onto the healthy tissue, dosage control, optimal concentration of drug in the tumor tissue, and more effective treatment which could improve outcome of therapy. Many organic and inorganic nanoparticles have been tested as drug carriers, but just few of them are in clinical use (liposomes and polymers). In recent years smart nanosystems for targeted drug delivery that respond to various stimuli including pH, ultrasound, temperature and light irradiation are in the center of many investigations

Cancer cell death induced by ruthenium complexes

Summary. Cancer is a complex and often fatal disease characterized by uncontrolled cell division. The most commonly used chemotherapeutics target rapidly dividing cancer cells but, at the same time, damage healthy dividing cells. New metal-based complexes, such as ruthenium complexes, that possess cytotoxic properties, have been developed to overcome these challenges. Ruthenium complexes achieve their antitumor effect mainly by inducing apoptosis. In recent years, induction of other types of cell death, such as ferroptosis and autophagy, was also reported. The dual role of autophagy in cancer cells is a major challenge for the application of metallocomplexes in cancer treatment, either as inducers or inhibitors of autophagy. Also, the effect of ruthenium complexes on other cellular processes such as cell cycle, cell migration, and adhesion are promising approaches in cancer treatment. Our results indicated a significant influence of Ru(II) complexes on these processes in melanoma, cervical and pancreatic cancer. The aim of this review is to summarize the latest data on the effect of ruthenium complexes on different types of cell death

Quantitative and qualitative comparison of mass spectra of vitamin E and A acquired with MALDI, SALDI and LDI TOF MS techniques

U ovom radu, uporedili smo masene spektre vitamina E i A dobijene laserskom jonizacijom i desorpcijom (LDI), sa organskim matricama (DHB, 9AA, CHCA i THAP) i pomoću supstrata na bazi titan dioksid (TiO2) nanokristala različitih oblika i dimenzija (koloidne nanočestice, prolatni nanosferoidi i nanotube) jer ovi faktori utiču na procese desorpcije i jonizacije. Za procenu ponovljivosti merenja unutar jednog dana i između dana LDI, MALDI i SALDI TOF tehnika korišćena je Excel alatka (ANOVA). Homogenost distribucije ko-kristala (smeše) uzorka/matrice (supstrata) na M(S)ALDI pločici je izražena kao srednja vrednost koeficijenta varijacije serije merenja. Rezultati su pokazali da je homogenost distribucije vitamina E i A na pločici povećana ukoliko se koristi bilo koji od nanokristala TiO2 u odnosu na homogenost samog uzorka i bilo koje kombinacije uzorak/matrica. Za ponovljivost rezultata u toku jednog dana pokazano je da se vrednosti varijacija sa određenim matricama smanju u odnosu na LDI. Međutim, sa supstratima je slika drugačija, vrednosti varijacija unutar jednog dana neuporedivo su niže nego što su vrednosti dobijene LDI i MALDI metodom. Isti trend kao za varijacije unutar jednog dana, zapaža se i za vrednosti varijacija između dana, ponovo su se supstrati pokazali kao znatno bolji izbor. Sumarno, pokazan je veliki potencijal koji imaju supstrati na bazi TiO2 za detekciju i kvantitativnu analizu vitamina E i A.In this work, we have compared mass spectra of vitamin E and A acquired with LDI TOF MS, MALDI TOF MS with organic matrices (DHB, 9-AA, CHCA and THAP) and SALDI TOF MS analysis with substrates based on TiO2 nanocrystals i.e. colloidal nanoparticles, prolate nanospheroids and nano tubes. Different size and shape of nanocrystals were used because of the already known fact that these factors have impact on desorption and ionization processes. The within-day and day-to-day precision LDI, SALDI and MALDI TOF MS was analysed using Excel tool (ANOVA). For calculation of homogeneity, we used the mean value of coefficient of variation of eight S/N values with nine repetition within three days for each analyte/substrate combination. The results showed that homogeneity of vitamin E and A was significantly improved when either of nanocrystals were used compared to LDI and MALDI approach. Within day precision with some matrices were slightly higher, but with some matrices precision were even lower comparing to LDI. The same pattern was observed with values of day-to-day variations, again nanocrystals were much better choice. In summary, it is shown that subrates based on TiO2 nanocrystals have the great potential for qualitative and quantitative analysis of vitamin E and A.53. Savetovanje Srpskog hemijskog društva : Program i kratki izvodi radova : Kragujevac, Srbija, 29. i 30. maj 2015

Antitumor effect of Ru(II) complex on A375 and HeLa cell growth, migration and adhesion ability

Platinum-based complexes represent the mainstay of treatment for various cancer types. However, their usage is often restricted by numerous side effects or intrinsic and acquired resistance. Therefore, significant research efforts have focused on developing therapeutics based on other transition metals, such as ruthenium 1,2. In this study, effects of transition metal complex, cis-dichlorobis (2,2ʹ-bipyridyl-4,4ʹ-dicarboxylic acid)ruthenium(II) (Ru(II) complex) were analyzed on A375 human melanoma and HeLa cell growth, adhesion ability andmigration. Cell viability assay indicated significant antitumor activity of Ru(II) complex on A375 (~60% of control) up to 72 h after treatment, but not on HeLa cells. However, analysis by clonogenic assay showed that growth of both cell lines was decreased 7 days after treatment. Growth inhibition was followed by G1 phase cell cycle arrest (5–10% G1 increase for A375 and 5–8% for HeLa cells compared to control). Moreover, Ru(II) complex increased adhesivity of A375 and HeLa cells by 11 and 16 % respectively and decreased cell migration, as shown by scratch assay. The obtained results indicate that the analyzed Ru(II) complex is a promising metallodrug, as itinduced growth inhibition of A375 and HeLa cells through induction of G1 arrest and decreased metastatic potential of these cells through the increase ofadhesivity and decrease of cell migration

Identification of protein target molecules for [Pd(dach)Cl2] complex in HeLa cervical carcinoma cells

In this work, we have applied the Informational Spectrum Method (ISM) to discover a potential protein target in the HeLa cervical cancer cell line for [Pd(dach)Cl2] complex. Since Pd complexes are considered an alternative to traditionally used Pt complexes in anti-cancer therapy, it is essential to elucidate the mechanism of their action. A detailed analysis that also involves screening the known protein databases revealed the proteins of the SOSS complex as the most probable [Pd(dach)Cl2] targets. Since this protein maintains genomic stability, this result shows the potential of the Pd(II) complex as an anti-cancer drug.ICCBIKG 2023 : 2nd International Conference on Chemo and Bioinformatics, September 28-29, 2023; Kragujeva

Inorganic Nanoparticles In Biology: Drug Carriers And Auxiliary Tools In Bioimaging And Bioanalytics

Among various nano-scaled materials composed from a spectrum of chemical compounds, inorganic nanoparticles are very attractive due to their physico-chemical properties, as well as their availability, simplicity, possibility of modifications, stability and biocompatibility. They are, on the one hand, an useful tool in advanced analytical chemistry, in particular for studying of biologically-relevant processes, but also important as functional parts of the systems designed for controlled and targeted delivery of medicaments for treatment of a variety of diseases and for imaging. So far, thousands of compounds and systems have been developed for the above-mentioned purposes, but there are only a few reviews dealing with these topics. The aim of this review is, thus, to summarize recent applications of nano-structured inorganic materials in the field of drug delivery, bioimaging and bioanalytics, and to give a prospective from the standpoint of biology-related applications

Development of photo-sensitive nanocomposite system for controlled metallo-drug delivery in skin cancer therapy

There has been a growing demand for development and improvement of cancer treatment in order to overcome disadvantages and limitations of traditional chemotherapy such as resistance, toxicity, and activity against a small number of tumor types. Photodynamic therapy is a rapidly developing cancer treatment that utilizes the combination of photoactive drug and/or carrier and light as an external stimulus to destroy tumors, achieve a maximum concentration of the drug on tumor site, reduce side effects of drug onto the healthy tissue, enable dosage control, and more effective treatment which could improve outcome of therapy [1]. We investigated possibility to use ТiО2 nanoparticles as a carrier for potential antitumor drug [Ru(II)(dcbpy)2Cl2], cis-dichlorobis (2, 2'-bipyridyl-4, 4'-dicarboxylicacid) ruthenium(II). Nanocomposite system has been formed by binding of ruthenium complex to the ТiО2 nanoparticles. Components of the system are selected according to their preferences, such as biocompatibility, photo activity, and easy surface modification for ТiО2, and less toxicity, significant activity against cancer metastases, and activity on tumors that were resistant to a variety of standard chemotherapeutic agents for Ru-complexes. Both components of the system are also photoactive, therefore potential for system manipulation and use in photodinamic therapy has been investigated by irradiation with UV and visible light. Additionally, the feasibility of using this system as a light-triggered drug delivery system was shown on amelanotic melanoma cancer line. The experimental results revealed a potential of nanocomposite system for long-term constant release of complex which is suitable for clinical practice. The further investigation of nanocomposite system indicated that it exhibited UV and red light susceptible drug release behavior [2]. More precisely, the system demonstrated slower complex release upon visible and increased release rate upon UV light illumination which was also in good correlation with the light–dependent cytotoxicity of the system demonstrated on amelanotic melanoma cancer line. The melanoma cancer cell death is enhanced by UV and reduced by red light in the presence of investigated nanocomposite system [3]. All obtained results suggested that nanocomposite system may have a potential use as a light sensitive drug delivery system in photodynamic therapy which could significantly contribute to development of more efficient and less invasive therapy of melanoma which is highly aggressive and deadliest form of skin cancer.VII International School and Conference on Photonics : PHOTONICA2019 : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 26-30; Belgrad

ROS-mediated proapoptotic antitumor effects of Ru(II) complex on pancreatic cancer cells

Existing therapies for the treatment of pancreatic cancer are insufficiently effective and accompanied by a large number of side effects. Ruthenium complexes have shown promising antitumor properties in the previous studies 1,2 . Thus, in this investigation, anticancer effects of cis-dichlorobis (2,2'-bipyridyl-4,4'dicarboxylic acid)ruthenium(II) (Ru(II) complex) were evaluated using human pancreatic carcinoma cell lines MIA PaCa-2 and PANC-1 in vitro. Cell viability estimated with SRB assay showed significant antitumor activity of Ru(II) complex on MIA PaCa-2 (~55% of control) 48 and 72 h after treatment. On the other hand, PANC-1 cell viability was decreased only 72 h after treatment with the highest concentration of Ru(II) complex (~70% of control). Seven days after the treatment, analysis of cell survival using clonogenic assay showed a significant decrease in cell growth in both cell lines. Ru(II) complex also caused G 1 cell cycle arrest of ~13% in both cell lines. The highest percentage of apoptotic MIA PaCa-2 cells was obtained 48 h after treatment. In addition, the intracellular level of reactive oxygen species (ROS) was significantly increased, whereas cell migration was reduced in both cell lines. Summarized, Ru(II)complex demonstrates antitumor properties mediated by increased oxidative stress and also implies the antimetastatic potential, which deserves further study

Design of Experiments mathematical methodology applied in MALDI-TOF-MS analysis

U ovom radu, matematička metoda Dizajn eksperimenta (eng. Design of Experiment, DoE) korišćena je za optimizaciju instrumetalnih parametara masenog spektrometra sa laserskom desorpcijom i jonizacijom pomoću „matriksa“ i sa analizatorom na bazi vremena preleta (MALDI TOF MS), a za analizu metalnih kompleksa. Ulazni parametri DoE metodologije bili su intenzitet lasera, napon na „gridu“ i broj impulsa lasera, dok su kao izlazni parametri od interesa bili odnos signal/šum i rezolucija. Različite vrednosti ulaznih parametra (njihovi nivoi) definisane su na osnovu dobijenih preliminarnih eksperimenata. Nakon utvrđivanja ulaznih i izlaznih parametara DoE eksperiment je izveden primenom Box-Behnken-ove metode. Teorijski predviđene vrednosti za dobijanje kvalitetnog masenog spektra metalnog kompleksa (snaga lasera-1220 W, napon „grida“-79 V i broj impulsa lasera-360) su eksperimentalno potvrđeni.In this work Design of Experiment mathematical methodology (DoE) was used for optimization the instrumental parameters of matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometer (MS) for the analysis of metal complex. The input factors in DoE methodology were laser intensity, grid voltage and number of laser shots, while the output response of interest were signal-to-noise ratio and resolution. The different values of input factors (their level) are defined according to the results obtained in preliminary experiments. After the identification of input factors and responses of interest the DoE experimental plan is created using Box-Behnken methode. Theoretically predicted values for obtaining high-quality mass spectra of metal complex (laser power – 1220 W, grid voltage – 79 V and number of laser shots – 360) are experimentally confirmed.53. Savetovanje Srpskog hemijskog društva : Program i kratki izvodi radova : Kragujevac, Srbija, 29. i 30. maj 2015

Application of Carbon-Based Nanocomposite Systems as Photosensitizers for Photodynamic Therapy

Small, carbon-based nanoparticles, carbon dots (CDs), are investigated as photosensitizers (PSs) for photodynamic therapy of cancers. The results presented here show biochemical changes in cancer cells treated with surface-modified CDs, which are augmented by illumination, indicating a high potential of CDs as selective drug carriers and potent PSs. In addition, we will show that CDs produced from black carrot extract (biomass) can be exploited for image-guided therapy and be cytotoxic for cancer cells, thanks to their fluorescence properties. Finally, since biomass-fabricated CDs interact strongly with nucleic acids, they can be further developed for cell cycle sensing purposes