Short-term autophagy inhibition by autophinib or SAR405 does not alter the effect of cisplatin on ATP production in prostate cancer cells.

OBJECTIVES: Cisplatin is a widely used anticancer drug for the treatment of many solid cancers. DNA damage is thought to be the key mechanism of cisplatin's anticancer activity. However, cisplatin may also affect cellular metabolism. The aim of this study was to determine the effect of cisplatin on the types of ATP production (OXPHOS versus glycolysis) and their rate in prostate cancer cells and to determine the potentially protective effect of autophagy and amino acids during cisplatin treatment. We also wanted to investigate the potential synergy between the metabolic effects of cisplatin on ATP production and the inhibition of autophagy. METHODS: Cisplatin treatment can significantly affect the metabolism of cancer cells. Important metabolic pathways can be altered, leading to changes in energy production and nutrient utilization. Autophagy and amino acid pool modulations can serve as protective mechanisms significantly affecting tumor cell survival under metabolic stress caused by anticancer treatment. By enabling the recycling of amino acids, autophagy helps cancer cells maintain cellular homeostasis and overcome nutrient limitations. Thus, inhibition of autophagy could have a supportive effect on the metabolic effects of cisplatin. RESULTS: After cisplatin treatment, ATP production by way of OXPHOS was significantly decreased in 22Rv1 and PC-3 cells. On the other hand, ATP production by glycolysis was not significantly affected in 22Rv1 cells. DU145 cells with dysfunctional autophagy were the most sensitive to cisplatin treatment and showed the lowest ATP production. However, short-term autophagy inhibition (24h) by autophinib or SAR405 in 22Rv1 and PC-3 cells did not alter the effect of cisplatin on ATP production. Levels of some amino acids (arginine, methionine) significantly affected the fitness of cancer cells. CONCLUSION: Persistent defects of autophagy can affect the metabolic sensitivity of cancer cells due to interference with arginine metabolism. Amino acids contained in the culture medium had an impact on the overall effect of cisplatin (Fig. 3, Ref. 38).

Chronic venous insufficiency and venous leg ulcers: Aetiology, on the pathophysiology-based treatment.

The chronic venous disease covers a wide spectrum of venous disorders that are characterized by severely impaired blood return that primarily affects veins in the lower extremities. Morphological and functional abnormalities of the venous system led to chronic venous insufficiency (CVI), and present as leg heaviness/achiness, edema, telangiectasia, and varices. The term 'chronic venous insufficiency' (CVI) refers to a disease of greater severity. Venous dysfunction is associated with venous hypertension and is associated with venous reflux due to poorly functioning or incompetent venous valves, which ultimately reduces venous return, leading to a cascade of morphological, physiological, and histologic abnormalities such as blood pooling, hypoxia, inflammation, swelling, skin changes (lipodermatosclerosis), and in severe cases, venous leg ulcers (VLU). This review summarizes recent knowledge about the aetiology, risk factors, and pathophysiology of VLU and compared the possibilities of their treatment.

Involvement of calcium signaling in different types of cell death in cancer.

Programmed cell death is a basic feature of chemotherapeutic (and also radiotherapeutic) intervention. Induction of cell death in tumor cells aims to kill preferentially the tumor cells, with minimal impact on the normal cells. Although apoptosis is the most obvious type of cell death induced by chemotherapeutics, several other types can also be activated, especially in conditions, where cells are resistant to apoptosis induction. Calcium signaling was shown to play an indisputable role in the activation of different types of cell death. Local increase of the calcium in time and precise place of this increase is secured by calcium transport systems. In this review, we summarized the involvement of some calcium transport systems in apoptosis, autophagy, necroptosis, ferroptosis, and mitophagy during cancer development and treatment.

Metabolic and Oxidative Changes in the Fern Adiantum raddianum upon Foliar Application of Metals.

Cadmium (Cd) or nickel (Ni) were applied as a foliar spray (1 µM solution over one month) to mimic air pollution and to monitor metabolic responses and oxidative stress in the pteridophyte species. Exogenous metals did not affect the metal content of the soil and had relatively little effect on the essential elements in leaves or rhizomes. The amounts of Cd and Ni were similar in treated leaves (7.2 µg Cd or 5.3 µg Ni/g DW in mature leaves compared with 0.4 µg Cd or 1.2 µg Ni/g DW in the respective control leaves), but Ni was more abundant in rhizomes (56.6 µg Ni or 3.4 µg Cd/g DW), resulting in a higher Cd translocation and bioaccumulation factor. The theoretical calculation revealed that ca. 4% of Cd and 5.5% of Ni from the applied solution per plant/pot was absorbed. Excess Cd induced stronger ROS production followed by changes in SOD and CAT activities, whereas nitric oxide (NO) stimulation was less intense, as detected by confocal microscopy. The hadrocentric vascular bundles in the petioles also showed higher ROS and NO signals under metal excess. This may be a sign of increased ROS formation, and high correlations were observed. Proteins and amino acids were stimulated by Cd or Ni application in individual organs, whereas phenols and flavonols were almost unaffected. The data suggest that even low levels of exogenous metals induce an oxidative imbalance, although no visible damage is observed, and that the responses of ferns to metals are similar to those of seed plants or algae.

Iron Complexes of Flavonoids-Antioxidant Capacity and Beyond.

Flavonoids are common plant natural products able to suppress ROS-related damage and alleviate oxidative stress. One of key mechanisms, involved in this phenomenon is chelation of transition metal ions. From a physiological perspective, iron is the most significant transition metal, because of its abundance in living organisms and ubiquitous involvement in redox processes. The chemical, pharmaceutical, and biological properties of flavonoids can be significantly affected by their interaction with transition metal ions, mainly iron. In this review, we explain the interaction of various flavonoid structures with Fe(II) and Fe(III) ions and critically discuss the influence of chelated ions on the flavonoid biochemical properties. In addition, specific biological effects of their iron metallocomplexes, such as the inhibition of iron-containing enzymes, have been included in this review.

Long-term impact of cadmium in protonema cultures of Physcomitrella patens.

Antioxidative responses of axenic protonema cultures of the moss Physcomitrella patens exposed to 10 µM Cd over 40 d were studied. Cd treatment suppressed growth by ca. 75% with concomitant browning of some filaments and suppression of chlorophyll autofluorescence but had no impact on tissue water content. Despite this negative growth responses which could be related to enhanced ROS formation (as detected using fluorescence staining reagents for total ROS, hydroperoxides and lipid peroxidation), some metabolites revealed strong elevation by Cd which could contribute to attenuation of long-term Cd stress (elevation of ascorbic, malic and citric acids). Molar ratio of malate to Cd was 12.7 and citrate to Cd 2.5, thus potentially contributing to Cd chelation. Interestingly, GSH/GSSG pool and nitric oxide formation remained unaltered by Cd. Accumulation of Cd reached 82 µg/g DW with bioaccumulation factor of 73. Data indicate that Cd induces elevation of potentially protective metabolites even after prolonged exposure though they do not prevent oxidative stress sufficiently.

Nitric oxide affects cadmium-induced changes in the lichen Ramalina farinacea.

Metabolic responses of epiphytic lichen Ramalina farinacea to cadmium (Cd) and/or nitric oxide (NO) scavenger (cPTIO) were studied. Accumulation of Cd and other metallic nutrients was not affected by cPTIO while total and absorbed amounts differed. Cd-induced NO formation was suppressed by cPTIO but ROS signal was synergistically enhanced, confirming that NO is essential to keep ROS under control. This excessive ROS generation could be a reason for depleted amount of all fatty acids, including SFAs, MUFAs and PUFAs. Total content of fatty acids reached 3.89 mg/g DW in control with linoleic (40%), palmitic (24%), oleic (12.8%) and stearic (8%) acids as major compounds: interestingly, shift in relative ratio of saturated (from 40 to 35% of total FAs) versus polyunsaturated fatty acids (from 42 to 48% of total FAs) was observed. Glutathione was suppressed by all treatments but Krebs acids were almost unaffected by cPTIO, indicating no regulatory role of NO in their accumulation. On the contrary, Cd-induced elevation in NO signal was related to increase in ascorbate and proline content while cPTIO suppressed it, indicating a tight relation between NO and these metabolites. Data are compared also with algae and vascular plants to show similarities between various life lineages.

Sodium/calcium exchanger is involved in apoptosis induced by H2S in tumor cells through decreased levels of intracellular pH.

We explored possibility that sodium/calcium exchanger 1 (NCX1) is involved in pH modulation and apoptosis induction in GYY4137 treated cells. We have shown that although 10 days treatment with GYY4137 did not significantly decreased volume of tumors induced by colorectal cancer DLD1 cells in nude mice, it already induced apoptosis in these tumors. Treatment of DLD1 and ovarian cancer A2780 cells with GYY4137 resulted in intracellular acidification in a concentration-dependent manner. We observed increased mRNA and protein expression of both, NCX1 and sodium/hydrogen exchanger 1 (NHE1) in DLD1-induced tumors from GYY4137-treated mice. NCX1 was coupled with NHE1 in A2780 and DLD1 cells and this complex partially disintegrated after GYY4137 treatment. We proposed that intracellular acidification is due to uncoupling of NCX1/NHE1 complex rather than blocking of the reverse mode of NCX1, probably due to internalization of NHE1. Results might contribute to understanding molecular mechanism of H2S-induced apoptosis in tumor cells.

Possible use of a Nicotiana tabacum 'Bright Yellow 2' cell suspension as a model to assess phytotoxicity of pharmaceuticals (diclofenac).

Growth and developmental changes in plants induced by pharmaceuticals reflect changes in processes at the cellular and subcellular levels. Due to their growth and cellular characteristics, plant cell suspension cultures can be a suitable model for assessing toxicity. In this study, 10-1000 µg/L of the non-steroidal anti-inflammatory drug diclofenac (DCF) decreased the viability of Nicotiana tabacum BY-2 cells after 24 h of treatment. Further, 0.1-10 mg/L DCF diminished the density of the cell suspension by 9-46% after 96 h of treatment, but at 1 and 10 µg/L, DCF increased the density by 13% and 5%, respectively, after 120 h. These changes were accompanied by increased production of total reactive oxygen species (ROS) and mitochondrial superoxide (up to 17-fold and 5-fold, respectively), and a decrease in the mitochondrial membrane potential (by ∼64%) especially at 1000 µg/L DCF. The increased ROS production was accompanied by decrease in level of reactive nitrogen species (RNS; by 36%) and total thiols (by 61%). Damage to BY-2 cells was evidenced by accumulation of neutral red in acidic compartments (up to 10-fold at 1000 µg/L DCF), and increase of autophagic vacuole formation (up to 8-fold at 1000 µg/L DCF). Furthermore, irregular or stretched nuclei were observed in nearly 27% and 50% of cells at 100 and 1000 µg/L DCF, respectively. Highest levels of chromatin condensation (11% of cells) and apoptotic DNA fragmentation (7%) were found at 10 µg/L DCF. The results revealed a significant effect of DCF on BY-2 cells after 24 h of exposure. Changes in the growth and viability parameters were indisputably related to ROS and RNS production, changes in mitochondrial function, and possible activation of processes leading to cell death.

Endogenous H2S producing enzymes are involved in apoptosis induction in clear cell renal cell carcinoma.

BACKGROUND: Knowledge about the expression and thus a role of enzymes that produce endogenous H2S - cystathionine-ß-synthase, cystathionine γ-lyase and mercaptopyruvate sulfurtransferase - in renal tumors is still controversial. In this study we aimed to determine the expression of these enzymes relatively to the expression in unaffected part of kidney from the same patient and to found relation of these changes to apoptosis. To evaluate patient's samples, microarray and immunohistochemistry was used. METHODS: To determine the physiological importance, we used RCC4 stable cell line derived from clear cell renal cell carcinoma, where apoptosis induction by a mixture of five chemotherapeutics with/without silencing of H2S-producing enzymes was detected. Immunofluorescence was used to determine each enzyme in the cells. RESULTS: In clear cell renal cell carcinomas, expression of H2S-producing enzymes was mostly decreased compared to a part of kidney that was distal from the tumor. To evaluate a potential role of H2S-producing enzymes in the apoptosis induction, we used RCC4 stable cell line. We have found that silencing of cystathionine-ß-synthase and cystathionine γ-lyase prevented induction of apoptosis. Immunofluorescence staining clearly showed that these enzymes were upregulated during apoptosis in RCC4 cells. CONCLUSION: Based on these results we concluded that in clear cell renal cell carcinoma, reduced expression of the H2S-producing enzymes, mainly cystathionine γ-lyase, might contribute to a resistance to the induction of apoptosis. Increased production of the endogenous H2S, or donation from the external sources might be of a therapeutic importance in these tumors.

Haloperidol Affects Plasticity of Differentiated NG-108 Cells Through σ1R/IP3R1 Complex.

Haloperidol is an antipsychotic agent that primarily acts as an antagonist of D2 dopamine receptors. Besides other receptor systems, it targets sigma 1 receptors (σ1Rs) and inositol 1,4,5-trisphosphate receptors (IP3Rs). Aim of this work was to investigate possible changes in IP3Rs and σ1Rs resulting from haloperidol treatment and to propose physiological consequences in differentiated NG-108 cells, i.e., effect on cellular plasticity. Haloperidol treatment resulted in up-regulation of both type 1 IP3Rs (IP3R1s) and σ1Rs at mRNA and protein levels. Haloperidol treatment did not alter expression of other types of IP3Rs. Calcium release from endoplasmic reticulum (ER) mediated by increased amount of IP3R1s elevated cytosolic calcium and generated ER stress. IP3R1s were bound to σ1Rs, and translocation of this complex from ER to nucleus occurred in the group of cells treated with haloperidol, which was followed by increased nuclear calcium levels. Haloperidol-induced changes in cytosolic, reticular, and nuclear calcium levels were similar when specific σ1 blocker -BD 1047- was used. Changes in calcium levels in nucleus, ER, and cytoplasm might be responsible for alterations in cellular plasticity, because length of neurites increased and number of neurites decreased in haloperidol-treated differentiated NG-108 cells.

Amino Acid Profiling of Zinc Resistant Prostate Cancer Cell Lines: Associations With Cancer Progression.

BACKGROUND: Failure in intracellular zinc accumulation is a key process in prostate carcinogenesis. Nevertheless, epidemiological studies of zinc administration have provided contradicting results. In order to examine the impact of the artificial intracellular increase of zinc(II) ions on prostate cancer metabolism, PNT1A, 22Rv1, and PC-3 prostatic cell lines-depicting different stages of cancer progression-and their zinc-resistant counterparts were used. To determine "benign" and "malignant" metabolic profiles, amino acid patterns, gene expression, and antioxidant capacity of these cell lines were assessed. METHODS: Amino acid profiles were examined using an ion-exchange liquid chromatography. Intracellular zinc content was measured by atomic absorption spectrometry. Metallothionein was quantified using differential pulse voltammetry. The content of reduced glutathione was determined using high performance liquid chromatography coupled with an electrochemical detector. Cellular antioxidant capacity was determined by the ABTS test and gene expression analysis was performed by qRT-PCR. RESULTS AND CONCLUSIONS: Long-term zinc treatment was shown to reroute cell metabolism from benign to more malignant type. Long-term application of high concentration of zinc(II) significantly enhanced cisplatin resistance, invasiveness, cellular antioxidant capacity, synthesis of glutathione, and expression of treatment resistance- and stemness-associated genes (SOX2, POU5F1, BIRC5). Tumorous cell lines universally displayed high accumulation of aspartate and sarcosine and depletion of essential amino acids. Increased aspartate/threonine, aspartate/methionine, and sarcosine/serine ratios were associated with cancer phenotype with high levels of sensitivity and specificity. Prostate 77: 604-616, 2017. © 2017 Wiley Periodicals, Inc.

Melatonin-Induced Changes in Cytosolic Calcium Might be Responsible for Apoptosis Induction in Tumour Cells.

BACKGROUND/AIMS: Melatonin is a hormone transferring information about duration of darkness to the organism and is known to modulate several signaling pathways in the cells, e.g. generation of endoplasmic reticulum stress, oxidative status of the cells, etc. Melatonin has been shown to exert antiproliferative and cytotoxic effects on various human cancers. We proposed that this hormone can differently affect tumour cells and healthy cells. METHODS: We compared the effect of 24 h melatonin treatment on calcium transport (by fluorescent probes FLUO-3AM and Rhod-5N), ER stress (determined as changes in the expression of CHOP, XBP1 and fluorescently, using Thioflavin T), ROS formation (by CellROX® Green/Orange Reagent) and apoptosis induction (by Annexin-V-FLUOS/propidiumiodide) in two tumour cell lines - ovarian cancer cell line A2780 and stable cell line DLD1 derived from colorectal carcinoma, with non-tumour endothelial cell line EA.hy926. RESULTS: Melatonin increased apoptosis in both tumour cell lines more than twice, while in EA.hy926 cells the apoptosis was increased only by 30%. As determined by silencing with appropriate siRNAs, both, type 1 sodium/calcium exchanger and type 1 IP3 receptor are involved in the apoptosis induction. Antioxidant properties of melatonin were significantly increased in EA.hy926 cells, while in tumour cell lines this effect was much weaker. CONCLUSION: Taken together, melatonin has different antioxidative effects on tumour cells compared to non-tumour ones; it also differs in the ability to induce apoptosis through the type 1 sodium/calcium exchanger, and type 1 IP3 receptor. Different targeting of calcium transport systems in tumour and normal, non-tumour cells is suggested as a key mechanism how melatonin can exert its anticancer effects. Therefore, it might have a potential as a novel therapeutic implication in cancer treatment.

Expression profiles of miR-29c, miR-200b and miR-375 in tumour and tumour-adjacent tissues of head and neck cancers.

Altered expression of microRNAs (miRNAs) has been shown in many types of malignancies including the head and neck squamous cell carcinoma (HNSCC). Although there are many new and innovative approaches in the treatment of HNSCC, a clear marker of this disease is still missing. Three candidate miRNAs (miR-29c-3p, miR-200b-5p and miR-375-3p) were studied in connection with HNSCC using quantitative real-time PCR expression levels in 42 tissue samples of HNSCC patients and histologically normal tumour-adjacent tissue samples of these patients. Primary HNSCC carcinoma tissues can be distinguished from histologically normal-matched noncancerous tumour-adjacent tissues based on hsa-miR-375-3p expression (sensitivity 87.5 %, specificity 65 %). Additionally, a significant decrease of hsa-miR-200b-5p expression was revealed in tumour-adjacent tissue samples of patients with node positivity. Lower expression of hsa-miR-200b-5p and hsa-miR-29c-3p in HNSCC tumour tissue was associated with higher tumour grade. Consequently, survival analysis was performed. Lower expression of hsa-miR-29c-3p in tumour-adjacent tissue was associated with worse overall and disease-specific survivals. Lower expression of miR-29c-3p in tumourous tissue was associated with worse relapse-free survival. hsa-miR-375-3p seems to be a relatively promising diagnostic marker in HNSCC but is not suitable for prognosis of patients. Furthermore, this study highlighted the importance of histologically normal tumour-adjacent tissue in HNSCC progress (significant decrease of hsa-miR-200b-5p expression in tumour-adjacent tissue of patients with node positivity and low expression of hsa-miR-29c-3p in HNSCC tumour-adjacent tissue associated with worse prognosis).

C-Geranylated Flavanones from Paulownia tomentosa Fruits as Potential Anti-inflammatory Compounds Acting via Inhibition of TNF-α Production.

Eleven new C-geranylated flavonoids, tomentodiplacones L, M, and N (1, 2, 10), tomentodiplacol B (3), 3',4'-O-dimethyl-5'-hydroxydiplacone (4), mimulones F, G, and H (5, 6, 7), paulowniones A (8) and B (9), tomentone (11), and 3',4',5'-trimethoxyflavanone (12), together with 11 known flavonoids (13-23), were isolated from fruits of Paulownia tomentosa. The structures of the compounds isolated were determined by spectroscopic data interpretation. The ability of compounds 1-23, together with the nonprenylated flavanones eriodictyol (24) and naringenin (25), to reduce the production of the pro-inflammatory cytokine TNF-α in THP-1 cells after bacterial lipopolysaccharide stimulation was evaluated using an in vitro screening test. The preliminary structure-activity relationships of these derivatives were also studied, and the correlation of their TNF-α inhibitory activity with their lipophilicity was investigated. The mechanism of action of compounds with significant antiphlogistic potential (4, 7, 10, 14, 22) was investigated. These compounds reduced both the secretion of TNF-α and the level of its corresponding mRNA. Compounds 4, 7, 10, 14, and 22 inhibited the nuclear translocation of NF-κB, which controls the expression of TNF-α, by blocking the degradation of IκB.

Turkish Scorzonera Species Extracts Attenuate Cytokine Secretion via Inhibition of NF-κB Activation, Showing Anti-Inflammatory Effect in Vitro.

Scorzonera species are used in different folk medicines to combat many diseases, including the illnesses connected with inflammation. Previous experiments showed anti-inflammatory activity of Scorzonera extracts in vivo. S. latifolia, S. cana var. jacquiniana, S. tomentosa, S. mollis ssp. szowitsii, S. eriophora, S. incisa, S. cinerea, and S. parviflora extracts were, therefore, evaluated for their inhibitory activities of TNF-α and IL-1ß production, and NF-κB nuclear translocation in THP-1 macrophages. The HPLC analysis was carried out to elucidate and to compare the composition of these extracts. Major compounds of the tested extracts have been isolated using different chromatographic techniques and further tested for their inhibitory activities on TNF-α and IL-1ß production. Several extracts showed promising anti-inflammatory activity in these in vitro tests. Results of HPLC analysis revealed chlorogenic acid as a compound present in all tested extracts. Hyperoside, quercetin-3-O-ß-d-glucoside and rutin were also present in varying amount in some Scorzonera species analyzed. Furthermore, eight phenolics which were identified as quercetin-3-O-ß-d-glucoside (1), hyperoside (2), hydrangenol-8-O-glucoside (3), swertisin (4), 7-methylisoorientin (5), 4,5-O-dicaffeoyl-quinic acid (6), 3,5-di-O-caffeoyl-quinic acid (7), and chlorogenic acid (8) have been isolated as major phenolic compounds of the tested extracts and, together with eight terpenoids (9-16) previously obtained from different Scorzonera species, have been tested for the inhibition of TNF-α production, unfortunately with no activity comparable with standard.

Application of BY-2 cell model in evaluating an effect of newly prepared potential calcium channel blockers.

Calcium channel blockers represent a group of therapeutically important compounds that have found an application in treatment of systemic vascular resistance and arterial pressure, eventually angina pectoris. We studied possibility of application of a BY-2 cell model to evaluate the potential of newly prepared potential calcium channel blockers. In the preliminary experiment, toxicity of studied compounds was determined. In the next experiment, we evaluated possible protective effect of studied compounds on programmed cell death induced by hydrogen peroxide on the BY-2 cells. Calcium channel blocker lanthanum ions and imidazole, inhibitor of NAD(P)H oxidase (EC 1.6.3.1) that prevents reactive oxygen species formation and programmed cell death, were used as reference compounds to compare the effect of studied compounds. We studied changes in the cell viability and growth as well as markers of cell proliferation, levels of intracellular free calcium ions, reactive oxygen species, lipid peroxidation, and markers of programmed cell death, mitochondrial membrane potential and caspase-like activity. Late signs of programmed cell death (changes in nuclear architecture) were also evaluated. Our experiments revealed protective potential of studied compounds against programmed cell death induced by hydrogen peroxide and possibility of application of the BY-2 cell culture to evaluate pharmacological effects of studied compounds in preliminary tests.

Evaluation of anti-inflammatory activity of prenylated substances isolated from Morus alba and Morus nigra.

Chromatographic separation of root extracts of Morus alba and M. nigra led to the identification of the 2-arylbenzofurans moracin C (1), mulberrofuran Y (2), and mulberrofuran H (3), and the prenylated flavonoids kuwanon E (4), kuwanon C (5), sanggenon H (6), cudraflavone B (7), and morusinol (8), and the Diels-Alder adducts soroceal (9), and sanggenon E (10). The cytotoxicity and their antiphlogistic activity, determined as the attenuation of the secretion of TNF-α and IL-1ß and the inhibition of NF-κB nuclear translocation in LPS-stimulated macrophages, were evaluated for compounds 1-10.

Modulation of induced cytotoxicity of doxorubicin by using apoferritin and liposomal cages.

Doxorubicin is an effective chemotherapeutic drug, however, its toxicity is a significant limitation in therapy. Encapsulation of doxorubicin inside liposomes or ferritin cages decreases cardiotoxicity while maintaining anticancer potency. We synthesized novel apoferritin- and liposome-encapsulated forms of doxorubicin ("Apodox" and "lip-8-dox") and compared its toxicity with doxorubicin and Myocet on prostate cell lines. Three different prostatic cell lines PNT1A, 22Rv1, and LNCaP were chosen. The toxicity of the modified doxorubicin forms was compared to conventional doxorubicin using the MTT assay, real-time cell impedance-based cell growth method (RTCA), and flow cytometry. The efficiency of doxorubicin entrapment was 56% in apoferritin cages and 42% in the liposome carrier. The accuracy of the RTCA system was verified by flow-cytometric analysis of cell viability. The doxorubicin half maximal inhibition concentrations (IC50) were determined as 170.5, 234.0, and 169.0 nM for PNT1A, 22Rv1, and LNCaP, respectively by RTCA. Lip8-dox is less toxic on the non-tumor cell line PNT1A compared to doxorubicin, while still maintaining the toxicity to tumorous cell lines similar to doxorubicin or epirubicin (IC50 = 2076.7 nM for PNT1A vs. 935.3 and 729.0 nM for 22Rv1 and LNCaP). Apodox IC50 was determined as follows: 603.1, 1344.2, and 931.2 nM for PNT1A, 22Rv1, and LNCaP.

Role of the 3-mercaptopyruvate sulfurtransferase in colon/colorectal cancers.

The 3-mercaptopyruvate sulfurtransferase (MPST) is a protein persulfidase, occurring mainly in mitochondria. Although function of this protein in cancer cells has been already studied, no clear outcome can be postulated up to now. Therefore, we focused on the determination of function of MPST in colon (HCT116 cells)/colorectal (DLD1 cells) cancers. In silico analysis revealed that in gastrointestinal cancers, MPST together with its binding partners can be either of a high risk or might have a protective effect. Silencing of MPST gene resulted in decreased ATP, while acetyl-CoA levels were elevated. Increased apoptosis was detected in cells with silenced MPST gene, which was accompanied by decrease in mitochondrial membrane potential, but no changes in IP3 receptor's protein. Mitochondria underwent activation of fission and elevated DRP1 expression after MPST silencing. Proliferation and migration of DLD1 and HCT116 cells were markedly affected, showing the importance of MPST protein in colon/colorectal cancer development.