Biocompatibility and Antioxidant Capabilities of Carbon Dots Obtained from Tomato (Solanum lycopersicum)

Since their discovery in 2004, carbon dots have attracted strong interest in the scientific community due to their characteristic properties, particularly their luminescence and their ease of synthesis and derivatization. Carbon dots can be obtained from different carbon sources, including natural products, resulting in a so-called ’green synthesis’. In this work, we obtain carbon dots from tomato juice in order to obtain nanoparticles with the antioxidant capabilities of the natural antioxidants present in that fruit. The obtained material is characterized regarding nanoparticle size distribution, morphology, surface functional groups and optic properties. Antioxidant properties are also evaluated through the DPPH method and their cytotoxicity is checked against human dermal fibroblast and A549 cell-lines. The results indicate that carbon dots obtained from tomato have a higher antioxidant power than other already-published antioxidant carbon dots. The bandgap of the synthesized materials was also estimated and coherent with the literature values. Moreover, carbon dots obtained from tomato juice are barely toxic for healthy cells up to 72 h, while they induce a certain cytotoxicity in A549 lung carcinoma cells.

The Effect of VPA Treatment on Radiolabeled DOTATATE Uptake: Differences Observed In Vitro and In Vivo

Background: To improve peptide receptor radionuclide therapy (PRRT), we aimed to enhance the expression of somatostatin type-2 receptors (SSTR2) in vitro and in vivo, using valproic acid (VPA). Methods: Human NCI-H69 small-cell lung carcinoma cells were treated with VPA, followed by [111In]In-DOTATATE uptake studies, RT-qPCR and immunohistochemistry analysis. Furthermore, NCI-H69 xenografted mice were treated with VPA or vehicle, followed by [177Lu]Lu-DOTATATE injection. Biodistribution studies were performed, and tissues were collected for further analysis. Results: VPA significantly increased SSTR2 expression in vitro. In animals, a statistically significant increased [177Lu]Lu-DOTATATE tumoral uptake was observed when VPA was administered eight hours before [177Lu]Lu-DOTATATE administration, but increased tumor SSTR2 expression levels were lacking. The animals also presented significantly higher [177Lu]Lu-DOTATATE blood levels, as well as an elevated renal tubular damage score. This suggests that the enhanced tumor uptake was presumably a consequence of the increased radiotracer circulation and the induced kidney damage. Conclusions: VPA increases SSTR2 expression in vitro. In vivo, the observed increase in tumoral [177Lu]Lu-DOTATATE uptake is not caused by SSTR2 upregulation, but rather by other mechanisms, e.g., an increased [177Lu]Lu-DOTATATE circulation time and renal toxicity. However, since both drugs are safely used in humans, the potential of VPA to improve PRRT remains open for investigation.

Serum deprivation enhanced ethanol-induced toxic responses in A549, lung carcinoma cells

Aim: The current study explores the toxic consequences of ethanol on human lung carcinoma cell, A549 in serum-deprived condition. Methodology: Human lung carcinoma cells, A549, were cultured in complete and serum-deprived medium for 6 hr. Subsequently, they were exposed to 50 mM and 100 mM concentrations of ethanol. Cytotoxicity studies linked with cell viability, oxidative stress, cell cycle arrest and micronuclei formation were performed using various toxicological parameters, namely MTT assay, DCFDA based ROS generation, cell cycle analysis and micronuclei formation assay. The cytotoxicity of ethanol in complete and serum deprived medium were compared at similar doses and time duration. Results: The metabolic viability assay demonstrated that 50 mM and 100 mM concentration of ethanol did not induce significant levels of cytotoxic alteration in A549 lung carcinoma cells in complete medium. However, in serum-deprived conditions, 50 mM and 100 mM ethanol concentration significantly altered cell viability. Further, exposure of 50 mM and 100 mM concentration of ethanol enhanced reactive oxygen species levels in A549 cells more significantly in serum-deprived conditions than in complete medium. In addition to cytotoxicity and oxidative stress, 50 mM and 100 mM ethanol also arrested the cells at G0 phase more significantly in serum deprived conditions compared to complete medium. Interpretation: Both 50 mM and 100 mM ethanol concentration enhanced the cell cytotoxicity and reactive oxygen species, cell cycle arrest and micronuclei formation more severely in serum-deprived medium than in complete medium (containing 10% FBS) under similar treatment conditions.

Cloning, Expression and Inhibitory Effects on Lewis Lung Carcinoma Cells of rAj-Tspin from Sea Cucumber (Apostichopus japonicus)

In recent years, sea cucumber has become a favorite healthcare food due to its characteristic prevention of cardiovascular diseases, suppression of tumors, as well as enhancement of immunity. In order to screen the anti-tumoral proteins or peptides from sea cucumber (Apostichopus japonicus), its cDNA library was analyzed, and a disintegrin-like and metalloproteinase with thrombospondin type 1 motif, member 13 (ADAMTS13)-like was found. ADAMTS13-like contains 10 thrombospondin 1 (TSP1) domains. Based on analysis of bioinformatics, the third TSP1 domain of this protein, which is further named Aj-Tspin, contains an arginine-glycine-aspartate (RGD) motif. Since our previous studies showed that the recombinant RGD-containing peptide from lampreys showed anti-tumoral activity, the third TSP1 domain of ADAMTS13-like was chosen to evaluate it’s effect on tumor proliferation and metastasis, despite the fact it shares almost no homologue with disintegrins from other species. After artificial synthesis, its cDNA sequence, Aj-Tspin, which is composed of 56 amino acids, was subcloned into a pET23b vector and expressed as a recombinant Aj-Tspin (rAj-Tspin) in a soluble form with a molecular weight of 6.976 kDa. Through affinity chromatography, rAj-Tspin was purified as a single protein. Both anti-proliferation and immunofluorescence assays showed that rAj-Tspin suppressed the proliferation of Lewis lung carcinoma (LLC) cells through apoptosis. Adhesion assay also displayed that rAj-Tspin inhibited the adhesion of LLC cells to ECM proteins, including fibronectin, laminin, vitronectin and collagen. Lastly, rAj-Tspin also suppressed the migration and invasion of LLC cells across the filter in transwells. Thus, the above indicates that rAj-Tspin might act as a potential anti-tumoral drug in the future and could also provide information on the nutritional value of sea cucumber.

Structural Analysis of SMYD3 Lysine Methyltransferase for the Development of Competitive and Specific Enzyme Inhibitors

Lysine methylation is among the key posttranslational modifications to histones that contribute to epigenetic regulation. SMYD3 is a lysine methyltransferase that is essential for the proliferation of a range of tumorigenic cells. The findings that SMYD3 is significantly upregulated in most colorectal carcinomas, hepatocellular carcinomas, and breast cell carcinomas support a model in which its aberrant expression modifies established patterns of gene expression, ultimately driving unrestrained proliferation. Herein, we dissect the unique structural features of SMYD3 relative to other SET enzymes, with an emphasis on the implications for selective design of therapeutics for the clinical management of cancer. Further, we illustrate the ability of inhibitors targeting the SET domain of SMYD3 to reduce the viability of colorectal and lung carcinoma cells.

CircZNF652 accelerates the proliferation and migration of primary lung carcinoma cells by downregulating miR-766

Purpose: To explore the biological functions and molecular mechanism of circZNF652 involvement in primary lung carcinoma.Methods: CircZNF652 levels in primary lung carcinoma cases and controls were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Its prognostic value in primary lung carcinoma was examined by depicting it with Kaplan-Meier curves. The biological functions of circZNF652 in regulating proliferative and migratory capacities in A549 and SPC-A-1 cells were analyzed from the curves. Interaction between circZNF652 and its downstream gene, miR-766, wasassessed, and their co-regulation on primary lung carcinoma was determined by rescue experiments.Results: CircZNF652 was abnormally and significantly upregulated in primary lung carcinoma cases (p< 0.05), resulting in a poor prognosis. The knockdown effect of circZNF652 attenuated the proliferative and migratory capacities of A549 and SPC-A-1 cells, and downregulated epithelial-mesenchymal transition (EMT)-associated genes. CircZNF652 bound and negatively regulated miR-766, a keydownstream gene involved in circZNF652-induced aggravation of primary lung carcinoma.Conclusion: CircZNF652 serves as an oncogene, triggering the aggravation of primary lung carcinoma by negatively regulating miR-766. The results of this study may provide new insights into the treatment of lung carcinoma.

Endothelial-specific depletion of TGF-β signaling affects lymphatic function

Background Transforming growth factor (TGF)-β is a multifunctional cytokine involved in cell differentiation, cell proliferation, and tissue homeostasis. Although TGF-β signaling is essential for maintaining blood vessel functions, little is known about the role of TGF-β in lymphatic homeostasis. Methods To delineate the role of TGF-β signaling in lymphatic vessels, TβRIIfl/fl mice were crossed with Prox1-CreERT2 mice to generate TβRIIfl/fl; Prox1-CreERT2 mice. The TβRII gene in the lymphatic endothelial cells (LECs) of the conditional knockout TβRIIiΔLEC mice was selectively deleted using tamoxifen. The effects of TβRII gene deletion on embryonic lymphangiogenesis, postnatal lymphatic structure and drainage function, tumor lymphangiogenesis, and lymphatic tumor metastasis were investigated. Results Deficiency of LEC-specific TGF-β signaling in embryos, where lymphangiogenesis is active, caused dorsal edema with dilated lymphatic vessels at E13.5. Postnatal mice in which lymphatic vessels had already been formed displayed dilation and increased bifurcator of lymphatic vessels after tamoxifen administration. Similar dilation was also observed in tumor lymphatic vessels. The drainage of FITC-dextran, which was subcutaneously injected into the soles of the feet of the mice, was reduced in TβRIIiΔLEC mice. Furthermore, Lewis lung carcinoma cells constitutively expressing GFP (LLC-GFP) transplanted into the footpads of the mice showed reduced patellar lymph node metastasis. Conclusion These data suggest that TGF-β signaling in LECs maintains the structure of lymphatic vessels and lymphatic homeostasis, in addition to promoting tumor lymphatic metastasis. Therefore, suppression of TGF-β signaling in LECs might be effective in inhibiting cancer metastasis.

Design and Synthesis of Novel Betulin Derivatives Containing Thio-/Semicarbazone Moieties as Apoptotic Inducers through Mitochindria-Related Pathways

Two new series of betulin derivatives with semicarbazone (7a–g) or thiosemicarbazone (8a–g) groups at the C-28 position were synthesized. All compounds were evaluated for their in vitro cytotoxicities in human hepatocellular carcinoma cells (HepG2), human breast carcinoma cells (MCF-7), human lung carcinoma cells (A549), human colorectal cells (HCT-116) and normal human gastric epithelial cells (GES-1). Among these compounds, 8f displayed the most potent cytotoxicity with an IC50 value of 5.86 ± 0.61 μM against MCF-7 cells. Furthermore, the preliminary mechanism studies in MCF-7 cells showed that compound 8f could trigger the intracellular mitochondrial-mediated apoptosis pathway by losing MMP level, which was related with the upregulation of Bax, P53 and cytochrome c expression; the downregulation of Bcl-2 expression; activation of the expression levels of caspase-3, caspase-9, cleaved caspase-3 and cleaved caspase-9; and an increase in the amounts of intracellular reactive oxygen species. These results indicated that compound 8f may be used as a valuable skeleton structure for developing novel antitumor agents.