In Vitro Evaluation of Anti-Lung Cancer and Anti-COVID-19 Effects using Fermented Black Color Ginseng Extract

Ginseng is known as the “king” of herbal plants and has been used widely in Asia for centuries. Ginseng contains active saponins, including protopanaxadiols, protopanaxatriols, and other compounds. There are many methods for processing ginseng, such as steaming, fermentation, expansion, and conversion of active compounds, which can improve its biological activity. In this study, we investigated the cytotoxic and oxidative effects of fermented black color ginseng (FBCG), black ginseng (BG), and white ginseng (WG) on a human lung carcinoma cell line (A549). Moreover, we found that treatment with FBCG induced oxidative stress in the A549 cell line and increases the apoptosis percentage; these effects were linked to the stimulation of the caspase 3/mitogen-activated protein kinase (caspase 3/MAPK) pathway. We also evaluated the anti-coronavirus disease-2019 (COVID-19) effect of FBCG on a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected Vero E6 cell line. Our results suggest that FBCG not only inhibits the replication of this strain of virus in the cell but also reduces the number of viral RNA (vRNA) copies in the extracellular environment. Taken together, these data show that FBCG has both potential anti-lung cancer and anti-COVID-19 effects.

Cytosolic 5′-Nucleotidase II Is a Sensor of Energy Charge and Oxidative Stress: A Possible Function as Metabolic Regulator

Cytosolic 5′-nucleotidase II (NT5C2) is a highly regulated enzyme involved in the maintenance of intracellular purine and the pyrimidine compound pool. It dephosphorylates mainly IMP and GMP but is also active on AMP. This enzyme is highly expressed in tumors, and its activity correlates with a high rate of proliferation. In this paper, we show that the recombinant purified NT5C2, in the presence of a physiological concentration of the inhibitor inorganic phosphate, is very sensitive to changes in the adenylate energy charge, especially from 0.4 to 0.9. The enzyme appears to be very sensitive to pro-oxidant conditions; in this regard, the possible involvement of a disulphide bridge (C175-C547) was investigated by using a C547A mutant NT5C2. Two cultured cell models were used to further assess the sensitivity of the enzyme to oxidative stress conditions. NT5C2, differently from other enzyme activities, was inactivated and not rescued by dithiothreitol in a astrocytoma cell line (ADF) incubated with hydrogen peroxide. The incubation of a human lung carcinoma cell line (A549) with 2-deoxyglucose lowered the cell energy charge and impaired the interaction of NT5C2 with the ice protease-activating factor (IPAF), a protein involved in innate immunity and inflammation.

CUT&RUN detects distinct DNA footprints of RNA polymerase II near the transcription start sites

CUT&RUN is a powerful tool to study protein-DNA interactions in vivo. DNA fragments cleaved by the targeted micrococcal nuclease identify the footprints of DNA-binding proteins on the chromatin. We performed CUT&RUN on human lung carcinoma cell line A549 maintained in a multi-well cell culture plate to profile RNA polymerase II. Long (> 270 bp) DNA fragments released by CUT&RUN corresponded to the bimodal peak around the transcription start sites, as previously seen with chromatin immunoprecipitation. However, we found that short (< 120 bp) fragments identify a well-defined peak localised at the transcription start sites. This distinct DNA footprint of short fragments, which constituted only about 5% of the total reads, suggests the transient positioning of RNA polymerase II before promoter-proximal pausing, which has not been detected in the physiological settings by standard chromatin immunoprecipitation. We showed that the positioning of the large-size-class DNA footprints around the short-fragment peak was associated with the directionality of transcription, demonstrating the biological significance of distinct CUT&RUN footprints of RNA polymerase II.

Structure of cyclin-dependent kinase 2 (CDK2) in complex with the specific and potent inhibitor CVT-313

CVT-313 is a potent CDK2 inhibitor that was identified by screening a purine-analogue library and is currently in preclinical studies. Since this molecule has the potential to be developed as a CDK2 inhibitor for cancer therapy, the potency of CVT-313 to bind and stabilize CDK2 was evaluated, together with its ability to inhibit aberrant cell proliferation. CVT-313 increased the melting temperature of CDK2 by 7°C in thermal stabilization studies, thus indicating its protein-stabilizing effect. CVT-313 inhibited the growth of human lung carcinoma cell line A549 in a dose-dependent manner, with an IC50 of 1.2 µM, which is in line with the reported biochemical potency of 0.5 µM. To support the further chemical modification of CVT-313 and to improve its biochemical and cellular potency, a crystal structure was elucidated in order to understand the molecular interaction of CVT-313 and CDK2. The crystal structure of CDK2 bound to CVT-313 was determined to a resolution of 1.74 Å and clearly demonstrated that CVT-313 binds in the ATP-binding pocket, interacting with Leu83, Asp86 and Asp145 directly, and the binding was further stabilized by a water-mediated interaction with Asn132. Based on the crystal structure, further modifications of CVT-313 are proposed to provide additional interactions with CDK2 in the active site, which may significantly increase the biochemical and cellular potency of CVT-313.

CUT&RUN detects distinct DNA footprints of RNA polymerase II near the transcription start sites

CUT&RUN is a powerful tool to study protein-DNA interactions in vivo. DNA fragments cleaved by the targeted micrococcal nuclease identify the footprints of DNA-binding proteins on the chromatin. We performed CUT&RUN on human lung carcinoma cell line A549 maintained in a multi-well cell culture plate to profile RNA polymerase II. Long (>270 bp) DNA fragments released by CUT&RUN corresponded to the bimodal peak around the transcription start sites, as previously seen with chromatin immunoprecipitation. However, we found that short (<120 bp) fragments identify a well-defined peak localised at the transcription start sites. This distinct DNA footprint of short fragments, which constituted only about 5% of the total reads, suggests the transient positioning of RNA polymerase II before promoter-proximal pausing, which has not been detected in the physiological settings by standard chromatin immunoprecipitation. We showed that the positioning of the large-size-class DNA footprints around the short-fragment peak was associated with the directionality of transcription, demonstrating the biological significance of distinct CUT&RUN footprints of RNA polymerase II.

Mixed Oleic Acid-Erucic Acid Liposomes as a Carrier for Anticancer Drugs

Background: Liposomes are mostly known to be prepared from phospholipids and lipids and have a remarkable capacity to encapsulate both lipophobic and lipophilic molecules. However, there is little research on developing fatty acid liposomes for chemotherapy. Objective: We have successfully prepared mixed fatty acid liposomes from two monounsaturated fatty acids, namely oleic acid and erucic acid, which stabilised by DOPEPEG2000. The Critical Vesicular Concentration (CVC) of liposomes was found to be within 0.09 to 0.21 mmol dm-3, with an average particle size of 400 nm. Methods: Encapsulation of various anticancer drugs such as folinic acid, methotrexate, doxorubicin, or irinotecan resulted in Encapsulation Efficiency (%EE) of up to 90%. Using a 3-(4, 5-dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the median Inhibitory Concentration (IC50) values of mixed oleic acid-erucic acid encapsulating hydrophilic drugs was remarkably reduced at the end of 24 hours of incubation with the human lung carcinoma cell line A549. Results: The results suggest that mixed oleic acid-erucic acid liposomes are a potential new approach to further develop as an alternative vehicle of various drugs for cancer treatment.

Photodynamic Therapy Excited by Cerenkov Radiation from Cesium-137 Irradiator: In Vitro Studies

Photodynamic therapy (PDT) is a non-invasive cancer therapy method that has been clinically approved for many years. Due to strong optical scattering and absorption of tissues, optical photons can only penetrate tissues several millimetres, which limits the applications of PDT to superficial lesions. To overcome the limitation of penetration depth, here we applied Cerenkov radiation, as generated by the high-energy -rays from radionuclide Cesium-137, to directly activate the porphyrin-based photosensitizer MPPa (Pyropheophorbide-a methyl ester) without any additional energy mediators. Experiments were conducted with A549 human lung carcinoma cell line. Moreover, to reduce the effects of possible plastic scintillation on PDT, we used black cell culture plates in these studies. We have also shown that the effects of the scintillations on PDT could be minimized. In our studies, we have excluded the effects of radiotherapy and drug toxicity. Our results indicated that the Cerenkov radiation generated from high energy -rays could be used to activate the photosensitizer MPPa in PDT, which could potentially overcome the penetration limitations of optical photon-based PDT, making the PDT a feasible and complementary cancer therapy for deep lesions.

Nonocarbolines A–E, β-Carboline Antibiotics Produced by the Rare Actinobacterium Nonomuraea sp. from Indonesia

During the course of our ongoing screening for novel biologically active secondary metabolites, the rare Actinobacterium, Nonomuraea sp. 1808210CR was found to produce five unprecedented β-carboline derivatives, nonocarbolines A–E (1–5). Their structures were elucidated from high-resolution mass spectrometry, 1D and 2D nuclear magnetic resonance spectroscopy, and the absolute configuration of 4 was determined by using the modified Mosher method. Nonocarboline B (2) displayed moderate antifungal activity against Mucor hiemalis, while nonocarboline D (4) exhibited significant cytotoxic activity against the human lung carcinoma cell line A-549 with the IC50 value of 1.7 µM.

Divergolides T–W with Apoptosis-Inducing Activity from the Mangrove-Derived Actinomycete Streptomyces sp. KFD18

Four new ansamycins, named divergolides T–W (1–4), along with two known analogs were isolated from the fermentation broth of the mangrove-derived actinomycete Streptomyces sp. KFD18. The structures of the compounds, including the absolute configurations of their stereogenic carbons, were determined by spectroscopic data and single-crystal X-ray diffraction analysis. Compounds 1–4 showed cytotoxic activity against the human gastric cancer cell line SGC-7901, the human leukemic cell line K562, the HeLa cell line, and the human lung carcinoma cell line A549, with 1 being the most active while compounds 5 and 6 were inactive against all the tested cell lines. Compounds 1 and 3 showed very potent and specific cytotoxic activities (IC50 2.8 and 4.7 µM, respectively) against the SGC-7901 cells. Further, the apoptosis-inducing effect of 1 and 3 against SGC-7901 cells was demonstrated by two kinds of staining methods for the first time.