A375 Human Melanoma Research Articles

Trimethyltin(IV) Bearing 3-(4-Methyl-2-oxoquinolin-1(2H)-yl)propanoate Causes Lipid Peroxidation-Mediated Autophagic Cell Death in Human Melanoma A375 Cells.

A novel trimethyltin(IV) complex (Me3SnL), derived from 3-(4-methyl-2-oxoquinolin-1(2H)-yl)propanoate ligand, has been synthesized and characterized by elemental microanalysis, UV/Vis spectrophotometry, FT-IR and multinuclear (1H, 13C and 119Sn) NMR spectroscopies. Furthermore, the structure of the ligand precursor HL was solved using SC-XRD (single-crystal X-ray diffraction). The prediction of UV/Vis and NMR spectra by quantum-chemical methods was performed and compared to experimental findings. The protein binding affinity of Me3SnL towards BSA was determined by spectrofluorometric titration and subsequent molecular docking simulations. Me3SnL has been evaluated for its in vitro anticancer activity against three human cell lines, MCF-7 (breast adenocarcinoma), A375 (melanoma) and HCT116 (colorectal carcinoma), and three mouse tumor cell lines, 4T1 (breast carcinoma), B16 (melanoma) and CT26 (colon carcinoma), using MTT and CV assays. The strong inhibition of A375 cell proliferation, ROS/RNS upregulation and robust lipid peroxidation lead to autophagic cell death upon treatment with Me3SnL.

Fucoxanthin induces human melanoma cytotoxicity by thwarting the JAK2/STAT3/BCL-xL signaling axis.

Melanoma is the most lethal skin malignancy. Fucoxanthin is a marine carotenoid with significant anticancer activities. Intriguingly, Fucoxanthin's impact on human melanoma remains elusive. Signal Transducer and Activator of Transcription 3 (STAT3) represents a promising target in cancer therapy due to its persistent activation in various cancers, including melanoma. Herein, we revealed that Fucoxanthin is cytotoxic to human melanoma cell lines A2758 and A375 while showing limited cytotoxicity to normal human melanocytes. Apoptosis is a primary reason for Fucoxanthin's melanoma cytotoxicity, as the pan-caspase inhibitor z-VAD-fmk drastically abrogated Fucoxanthin-elicited clonogenicity blockage. Besides, Fucoxanthin downregulated tyrosine 705-phosphorylated STAT3 (p-STAT3 (Y705)), either inherently present in melanoma cells or inducible by interleukin 6 (IL-6) stimulation. Notably, ectopic expression of STAT3-C, a dominant-active STAT3 mutant, abolished Fucoxanthin-elicited melanoma cell apoptosis and clonogenicity inhibition, supporting the pivotal role of STAT3 blockage in Fucoxanthin's melanoma cytotoxicity. Moreover, Fucoxanthin lowered BCL-xL levels by blocking STAT3 activation, while ectopic BCL-xL expression rescued melanoma cells from Fucoxanthin-induced killing. Lastly, Fucoxanthin was found to diminish the levels of JAK2 with dual phosphorylation at tyrosine residues 1007 and 1008 in melanoma cells, suggesting that Fucoxanthin impairs STAT3 signaling by blocking JAK2 activation. Collectively, we present the first evidence that Fucoxanthin is cytotoxic selectively against human melanoma cells while sparing normal melanocytes. Mechanistically, Fucoxanthin targets the JAK2/STAT3/BCL-xL antiapoptotic axis to provoke melanoma cell death. This discovery implicates the potential application of Fucoxanthin as a chemopreventive or therapeutic strategy for melanoma management.

Exploring the Antimelanoma Potential of Betulinic Acid Esters and Their Liposomal Nanoformulations

Betulinic acid is a naturally occurring pentacyclic triterpene belonging to the lupane-group that exhibits a wide range of pharmacological activities. BA derivatives are continuously being researched due to their improved anticancer efficacy and bioavailability. The current research was conducted in order to determine the antiproliferative potential of three synthesized BA fatty esters using palmitic, stearic and butyric acids and their liposomal nanoformulations. The cytotoxic potential of BA fatty esters (Pal-BA, St-BA, But-BA) and their respective liposomal formulations (Pal-BA-Lip, St-BA-Lip, But-BA-Lip) has been assessed on HaCaT immortalized human keratinocytes and A375 human melanoma cells. Both the esters and their liposomes acted as cytotoxic agents against melanoma cells in a time- and dose-dependent manner. The butyryl ester But-BA outperformed BA in terms of cytotoxicity (IC50 60.77 μM) while the nanoformulations St-BA-Lip, But-BA-Lip and BA-Lip also displayed IC50 values (60.11, 50.71 and 59.01 μM) lower compared to BA (IC50 65.9 μM). The morphological evaluation revealed that the A375 cells underwent morphological changes consistent with apoptosis following 48 h treatment with the tested compounds, while the HaCaT cells’ morphology remained unaltered. Both the esters and their liposomal formulations were able to inhibit the migration of the melanoma cells, suggesting a significant antimetastatic effect. The quantitative real-time PCR revealed that all tested samples were able to significantly increase the expression of the pro-apoptotic Bax and inhibit the anti-apoptotic Bcl-2 proteins. This effect was more potent in the case of liposomal nanoformulations versus non-encapsulated compounds, and overall, But-BA and its formulation exhibited the best results in this regard.

Identification of circRNA-miRNA-mRNA Network Regulated by Hsp90 in Human Melanoma A375 Cells.

Melanoma is the deadliest form of skin cancer. Heat shock protein 90 (Hsp90) is highly expressed in human melanoma. Hsp90 inhibitors can suppress the growth of human melanoma A375 cells; however, the underlying mechanism remains unclear. A375 cells were treated with SNX-2112, an Hsp90 inhibitor, for 48 h, and wholetranscriptome sequencing was performed. A total of 2,528 differentially expressed genes were identified, including 895 upregulated and 1,633 downregulated genes. Pathway enrichment analyses of differentially expressed mRNAs identified the extracellular matrix (ECM)-receptor interaction pathway as the most significantly enriched pathway. The ECM receptor family mainly comprises integrins (ITGs) and collagens (COLs), wherein ITGs function as the major cell receptors for COLs. 19 upregulated miRNAs were found to interact with 6 downregulated ITG genes and 8 upregulated miRNAs were found to interact with 3 downregulated COL genes. 9 differentially expressed circRNAs in SNX-2112- treated A375 cells were identified as targets of the ITG- and COL-related miRNAs. Based on the differentially expressed circRNAs, miRNAs, and mRNAs, ITGs- and COL-based circRNAmiRNA- mRNA regulatory networks were mapped, revealing a novel regulatory mechanism of Hsp90-regulated melanoma. Targeting the ITG-COL network is a promising approach to the treatment of melanoma.

Pholiotic acid promotes apoptosis in human metastatic melanoma cells

Mushrooms produce a great variety of secondary metabolites that can be successful in both prevention and treatment of various cancers. In particular, higher Basidiomycete mushrooms contain various types of biologically active low-molecular compounds in fruiting bodies with suggested anticarcinogenic effects. The polyamine analogue {(2R)-2-[(S)-3-hydroxy-3-methylglutaryloxy] putrescine dicinnamamide} indicated with the name pholiotic acid, isolated for the first time by us from the fruiting bodies of the Basidiomycete Pholiota spumosa (Fr.) Sing. (Strophariaceae), inhibited the viability of human prostate cancer cells, such as other polyamine synthetic analogues that have shown antitumor activity in several types of cancer, including melanoma. Melanoma is an aggressive skin cancer that can metastasize to other organs and presents a high resistance to conventional therapies. In light of these considerations, the present study was therefore designed to assess whether this putrescine derivative could inhibit the growth of human metastatic melanoma cell lines, M14 and A2058. The results obtained demonstrate that this natural compound, at 12.5–50 μM concentration, was able to reduce cell viability of both cancer cells inducing cell death by intrinsic apoptotic pathway that probably involves PTEN activity, inhibition of Hsp70 expression and reactive oxygen species production. On the other hand, the increased expression of enzymes involved in polyamine catabolism trigger apoptotic cell death leading to polyamine depletion and generation of reactive oxygen species as by-products. In conclusion, these findings, starting point for further investigation, implement available our data to support pholiotic acid as an attractive potential chemopreventive agent, and provide a basis for further research into the use of this polyamine derivative as potential anticancer agent for melanoma in combination with existing therapies to improve treatment efficacy and overcome the obstacle of drug resistance.

Recent Updates Regarding the Antiproliferative Activity of Galium verum Extracts on A375 Human Malignant Melanoma Cell Line.

The biological activity of Galium verum herba was exerted on various tumor cell lines with incredible results, but their potential effect on malignant melanoma has not been established yet. Therefore, the current study was structured in two directions: (i) the investigation of the phytochemical profile of diethyl ether (GvDEE) and butanol (GvBuOH) extracts of G. verum L. and (ii) the evaluation of their biological profile on A375 human malignant melanoma cell line. The GvDEE extract showed an FT-IR profile different from the butanol one, with high antioxidant capacity (EC50 of GvDEE = 0.12 ± 0.03 mg/mL > EC50 of GvBuOH = 0.18 ± 0.05 mg/mL). The GvDEE extract also showed antimicrobial potential, especially against Gram-positive bacteria strains, compared to the butanol extract, which has no antimicrobial activity against any bacterial strain tested. The results regarding the antitumor potential showed that both extracts decreased A375 cell viability largely (69% at a dose of 55 µg/mL of the GvDEE extract). Moreover, both extracts induce nuclear fragmentation by forming apoptotic bodies and slight chromatin condensation, which is more intense for GvDEE. Considering the results, one can state that the Galium verum herba possesses antitumor effects on the A375 human malignant melanoma cell line, a promising phytocompound for the antitumor approach to skin cancer.

How to Build Plasmon-Driven Molecular Jackhammers that Disassemble Cell Membranes and Cytoskeletons in Cancer.

Plasmon-driven molecular machines with ultrafast motion at the femtosecond scale are effective for the treatment of cancer and other diseases. It is recently shown that cyanine dyes act as molecular jackhammers (MJH) through vibronic (vibrational and electronic mode coupling) driven activation that causes the molecule to stretch longitudinally and axially through concerted whole molecule vibrations. However, the theoretical and experimental underpinnings of these plasmon-driven motions in molecules are difficult to assess. Here the use of near-infrared (NIR) light-activated plasmons in a broad array of MJH that mechanically disassemble membranes and cytoskeletons in human melanoma A375 cells is described. The characteristics of plasmon-driven molecular mechanical disassembly of supramolecular biological structures are observed and recorded using real-time fluorescence confocal microscopy. Molecular plasmon resonances in MJH are quantified through a new experimental plasmonicity index method. This is done through the measurement of the UV-vis-NIR spectra in various solvents, and quantification of the optical response as a function of the solvent polarity. Structure-activity relationships are used to optimize the synthesis of plasmon-driven MJH, applying them to eradicate human melanoma A375 cells at low lethal concentrations of 75nm and 80mWcm-2 of 730nm NIR-light for 10min.

Synthesis, characterization, DNA/BSA-binding affinity and biological activity of dinuclear palladium(II) complexes with aromatic N-heterocyclic bridging ligand

Dinuclear palladium(II) complexes, [{Pd(en)Cl}2(μ-L)](NO3)2 (L is bridging ligand pirazine (Pd1), pyrimidine (Pd2), pyridazine (Pd3), phenazine (Pd4) and en is ethylenediamine), were synthesized and characterized. The interactions of the synthesized palladium(II) complexes with biomolecules such as DNA and BSA were studied using UV–Vis spectroscopy and fluorescence spectroscopy. Analysis of tumoricidal activity of investigated complexes, tested on several tumor cell lines of human and mouse origin, revealed that Pd1 and Pd2 exhibited weak cytotoxic potential at lower concentrations. However, Pd3 showed higher cytotoxicity effects on the human MDA-MB 468 breast carcinoma and A375 melanoma cell lines, while Pd4 exhibited tumoricidal potential against MDA-MB 468 cells and A549 human lung adenocarcinoma cells. Interestingly, A375 human melanoma cells were highly sensitive to Pd4 treatment similarly to the effect of cisplatin. Further, the antimicrobial effects of tested compounds were evaluated using different species of Gram-positive and Gram-negative bacteria, as well as yeasts. Pd1–Pd4 showed variable antimicrobial activity depending on the microorganism species. Among tested complexes, Pd4 exhibited the highest antimicrobial activity. The obtained data suggest that palladium(II) complexes might be further investigated as potential antitumor and antimicrobial agents.

Nitidine Chloride Inhibits Proliferation and Induces Mitochondrial-Mediated Apoptosis of Human Melanoma A375 and A2058 Cells In Vitro

Melanoma is a malignant tumor transforming from normal melanocytes, with strong invasion and low survival rate. Nitidine chloride (NC) is a natural benzophenidine alkaloid extracted from the roots of traditional Chinese medicine zanthoxylum nitidum. In recent years, many studies have found that NC may have strong anti-tumor activity. However, the efficacy of NC against melanoma has rarely been reported, and the potential molecular mechanism remains unknown. Our study explored the effects of NC on the proliferation and apoptosis of human melanoma A375 and A2058 cells. CCK-8 was utilized to detect the effects of different concentrations of NC on the proliferation of A375 and A2058 cells. Within a certain concentration and time range, NC can inhibit the viability of A375 and A2058 cells significantly in a time-dose-dependent manner. In addition, NC-induced apoptosis was confirmed by DAPI staining and flow cytometry analysis of Annexin V-FITC/PI. Moreover, we observed that the ratio of Bax/Bcl-2 in the cytoplasm increases, activating Caspase-3/-9 and ultimately inducing apoptosis via the mitochondrial pathway. Our study indicated that NC has anti-tumor properties against human melanoma cells through inhibiting proliferation and inducing apoptosis. Therefore, the results provide new insights for future work on the utilization of NC in malignant melanoma treatment.

Potential Beneficial Effects of Salvianic Acid A and Salvianolic Acid B in Skin Whitening

Objective Natural product-derived biomaterials are highly desired as possible ingredients in cosmetics, as they are often safe and effective. Salvianic acid A (SAA) and salvianolic acid B (SAB) are the primary water-soluble ingredients of Salvia miltiorrhiza Bunge ( Lamiaceae). These compounds have extensive applications as both effective and biocompatible bioactive agents for the treatment of various diseases including cardiovascular disorders, liver ailments, and neuroprotection. This study aimed to evaluate the skin-whitening effects of SAA and SAB on co-cultured human melanoma A375 cells and human keratinocytes HaCaT cells, with the intention of investigating their potential as cosmetic ingredients. Methods First, we assessed the SAA and SAB's efficacy on cells proliferation using MTT assay, as well as their inhibition on intracellular tyrosinase (TYR) activity. Next, we evaluated their effects on the mRNA expression levels of TYR and its related proteins. Furthermore, the whitening efficacy of SAA and SAB was assessed by observing the decrease in melanin content in treated human amalignant melanoma A375 and human keratinocyte HaCaT cells. Results Both SAA and SAB inhibited the activity of TYR and decreased the mRNA expression of TYR-related proteins, thereby inhibiting melanin synthesis. Conclusion Our results suggest that both SAA and SAB can be applied as natural and novel cosmetics materials having a whitening function, which could be beneficial in the cosmeceutical industry.

Low-molecular-weight fucoidan inhibits the proliferation of melanoma via Bcl-2 phosphorylation and PTEN/AKT pathway.

Fucoidan, a sulfate polysaccharide obtained from brown seaweed, has various bioactive properties, including anti-inflammatory, anti-cancer, anti-viral, anti-oxidant, anti-coagulant, anti-thrombotic, anti-angiogenic, and anti-Helicobacter pylori properties. However, the effects of low-molecular-weight fucoidan (LMW-F) on melanoma cell lines and three dimensional (3D) cell culture models are not well understood. This study aimed to investigate the effects of LMW-F on A375 human melanoma cells and cryopreserved biospecimens derived from patients with advanced melanoma. Ultrasonic wave was used to fragment fucoidan derived from Fucus vesiculosus into smaller LMW-F. MTT and live/dead assays showed that LMW-F inhibited cell proliferation in both A375 cells and patient-derived melanoma explants in a 3D-printed collagen scaffold. The PTEN/AKT pathway was found to be involved in the anti-melanoma effects of fucoidan. Western blot analysis revealed that LMW-F reduced the phosphorylation of Bcl-2 at Thr 56, which was associated with the prevention of anti-apoptotic activity of cancer cells. Our findings suggested that LMW-F could enhance anti-melanoma chemotherapy and improve the outcomes of patients with melanoma resistance.

Low-dose imiquimod induces melanogenesis in melanoma cells through an ROS-mediated pathway

BackgroundMelanogenesis is the process of melanin maturation which not only protects skin from UV radiation but also plays an important role in antigenicity of melanomas. Imiquimod (IMQ) is a toll-like receptor 7 (TLR7) agonist that exhibits antiviral and anticancer activity. ObjectiveTo explore whether IMQ could induce melanogenesis in melanoma cells. MethodsThe mouse melanoma cell line B16F10, the mouse immortalized melanocyte Melan-A, and human melanoma cell lines MNT-1, C32 and A375 were utilized in this study. The pigmented level was observed by the centrifuged cell pellet. The intracellular and extracellular melanin levels were examined in the absorbance in NaOH-extracted cell lysate and cell-cultured medium, respectively. The expression of melanogenesis related proteins was examined by immunoblotting. The intracellular cyclic AMP amount was evaluated by the cAMP Glo assay kit. The activity of phosphodiesterase 4B (PDE4B) was investigated by CREB reporter assay with overexpressed PDE4B or not. ResultsWe demonstrated that a low dose of IMQ could trigger melanogenesis in B16F10 cells. IMQ induced microphthalmia-associated transcription factor (MITF) nuclear translocation, upregulated the expression of melanogenesis-related proteins, increased tyrosinase (TYR) activity, and led to pigmentation in B16F10 cells. Next, we found that IMQ-induced melanogenesis was activated by excessive intracellular cAMP accumulation, which was regulated through IMQ-mediated PDE4B inhibition. Finally, IMQ-induced ROS production was found to be involved in melanogenesis by its control of PDE4B activity. ConclusionsLow dose of IMQ could activate melanogenesis through the ROS/PDE4B/PKA pathway in melanoma cells.

Copper(II) Complexes with 1-(Isoquinolin-3-yl)heteroalkyl-2-ones: Synthesis, Structure and Evaluation of Anticancer, Antimicrobial and Antioxidant Potential.

Four copper(II) complexes, C1-4, derived from 1-(isoquinolin-3-yl)heteroalkyl-2-one ligands L1-4 were synthesized and characterized using an elemental analysis, IR spectroscopic data as well as single crystal X-ray diffraction data for complex C1. The stability of complexes C1-4 under conditions mimicking the physiological environment was estimated using UV-Vis spectrophotometry. The antiproliferative activity of both ligands L1-4 and copper(II) compounds C1-4 were evaluated using an MTT assay on four human cancer cell lines, A375 (melanoma), HepG2 (hepatoma), LS-180 (colon cancer) and T98G (glioblastoma), and a non-cancerous cell line, CCD-1059Sk (human normal skin fibroblasts). Complexes C1-4 showed greater potency against HepG2, LS180 and T98G cancer cell lines than etoposide (IC50 = 5.04-14.89 μg/mL vs. IC50 = 43.21->100 μg/mL), while free ligands L1-4 remained inactive in all cell lines. The prominent copper(II) compound C2 appeared to be more selective towards cancer cells compared with normal cells than compounds C1, C3 and C4. The treatment of HepG2 and T98G cells with complex C2 resulted in sub-G1 and G2/M cell cycle arrest, respectively, which was accompanied by DNA degradation. Moreover, the non-cytotoxic doses of C2 synergistically enhanced the cytotoxic effects of chemotherapeutic drugs, including etoposide, 5-fluorouracil and temozolomide, in HepG2 and T98G cells. The antimicrobial activities of ligands L2-4 and their copper(II) complexes C2-4 were evaluated using different types of Gram-positive bacteria, Gram-negative bacteria and yeast species. No correlation was found between the results of the antiproliferative and antimicrobial experiments. The antioxidant activities of all compounds were determined using the DPPH and ABTS radical scavenging methods. Antiradical tests revealed that among the investigated compounds, copper(II) complex C4 possessed the strongest antioxidant properties. Finally, the ADME technique was used to determine the physicochemical and drug-likeness properties of the obtained complexes.

In vitro cytotoxic potential of cow dung and expired tomato sauces-derived carbon nanodots against A-375 human melanoma cell line

Converting biowaste into a functional product is put to the test by the growing amount of biowaste in the world and the environmental problems it causes. In this research study, we synthesized, characterized, and evaluated bluish-green luminescent carbon nanodots (CNDs) from cow dung and expired tomato sauces via a hydrothermal synthesis method at 160 °C for 8 h. The carbon nanodots were fabricated without additional passivating agents and exhibited good physicochemical and optical properties. The intrinsic properties of carbon nanodots were characterized using various spectral techniques. First, we evaluated the cytotoxic potential of carbon nanodots against A-375 human melanoma cell lines. This study revealed that carbon nanodots exhibited potent cytotoxicity and significantly inhibited the proliferation of A-375 cells in a dose-dependent manner. Next, we demonstrated these carbon nanodot's free radical scavenging potential by employing 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The bluish-green fluorescent carbon nanodots fabricated using a green synthesis approach have broad potential for biological applications.

Decavanadate-Bearing Guanidine Derivatives Developed as Antimicrobial and Antitumor Species.

To obtain biologically active species, a series of decavanadates (Hpbg)4[H2V10O28]·6H2O (1) (Htbg)4[H2V10O28]·6H2O; (2) (Hgnd)2(Hgnu)4[V10O28]; (3) (Hgnu)6[V10O28]·2H2O; and (4) (pbg = 1-phenyl biguanide, tbg = 1-(o-tolyl)biguanide, gnd = guanidine, and gnu = guanylurea) were synthesized and characterized by several spectroscopic techniques (IR, UV-Vis, and EPR) as well as by single crystal X-ray diffraction. Compound (1) crystallizes in space group P-1 while (3) and (4) adopt the same centrosymmetric space group P21/n. The unusual signal identified by EPR spectroscopy was assigned to a charge-transfer π(O)→d(V) process. Both stability in solution and reactivity towards reactive oxygen species (O2- and OH·) were screened through EPR signal modification. All compounds inhibited the development of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis bacterial strains in a planktonic state at a micromolar level, the most active being compound (3). However, the experiments conducted at a minimal inhibitory concentration (MIC) indicated that the compounds do not disrupt the biofilm produced by these bacterial strains. The cytotoxicity assayed against A375 human melanoma cells and BJ human fibroblasts by testing the viability, lactate dehydrogenase, and nitric oxide levels indicated compound (1) as the most active in tumor cells.

AM1172 (a hydrolysis-resistant endocannabinoid analog that inhibits anandamide cellular uptake) reduces the viability of the various melanoma cells, but it exerts significant cytotoxic effects on healthy cells: an in vitro study based on isobolographic analysis.

Despite great advances in our understanding of the impact of cannabinoids on human organism, many of their properties still remain undetermined, including their potential antineoplastic effects. This study was designed to assess the anti-proliferative and cytotoxic effects of AM1172 (a hydrolysis-resistant endocannabinoid analog that inhibits anandamide cellular uptake) administered alone and in combinations with docetaxel (DOCX), paclitaxel (PACX), mitoxantrone (MTX) and cisplatin (CDDP) on various human malignant melanoma A375, FM55P, SK-MEL 28 and FM55M2 cell lines. In the MTT, LDH, and BrdU assays, the potency and safety of AM1172 when administered alone and in combinations with DOCX, PACX, MTX, and CDDP were determined. The isobolographic analysis revealed that combinations of AM1172 with PACX, DOCX, MTX, and CDDP exerted additive interactions, except for a combination of AM1172 with PACX in primary melanoma A375 cell line, for which synergy was observed (*p<0.05). Nevertheless, AM1172 when administered alone produced cytotoxic effects on healthy human melanocytes (HEMa-LP) and human keratinocytes (HaCaT), which unfortunately limits its potential therapeutic utility. AM1172 cannot be used separately as a chemotherapeutic drug, but it can be combined with PACX, DOCX, MTX, and CDDP, offering additive interactions in terms of the anti-proliferative effects in various malignant melanoma cell lines.

Functional analysis of recurrent CDC20 promoter variants in human melanoma

Small nucleotide variants in non-coding regions of the genome can alter transcriptional regulation, leading to changes in gene expression which can activate oncogenic gene regulatory networks. Melanoma is heavily burdened by non-coding variants, representing over 99% of total genetic variation, including the well-characterized TERT promoter mutation. However, the compendium of regulatory non-coding variants is likely still functionally under-characterized. We developed a pipeline to identify hotspots, i.e. recurrently mutated regions, in melanoma containing putatively functional non-coding somatic variants that are located within predicted melanoma-specific regulatory regions. We identified hundreds of statistically significant hotspots, including the hotspot containing the TERT promoter variants, and focused on a hotspot in the promoter of CDC20. We found that variants in the promoter of CDC20, which putatively disrupt an ETS motif, lead to lower transcriptional activity in reporter assays. Using CRISPR/Cas9, we generated an indel in the CDC20 promoter in human A375 melanoma cell lines and observed decreased expression of CDC20, changes in migration capabilities, increased growth of xenografts, and an altered transcriptional state previously associated with a more proliferative and less migratory state. Overall, our analysis prioritized several recurrent functional non-coding variants that, through downregulation of CDC20, led to perturbation of key melanoma phenotypes.

Prostaglandin E2 Exposure Disrupts E-Cadherin/Caveolin-1-Mediated Tumor Suppression to Favor Caveolin-1-Enhanced Migration, Invasion, and Metastasis in Melanoma Models.

Caveolin-1 (CAV1) is a membrane-bound protein that suppresses tumor development yet also promotes metastasis. E-cadherin is important in CAV1-dependent tumor suppression and prevents CAV1-enhanced lung metastasis. Here, we used murine B16F10 and human A375 melanoma cells with low levels of endogenous CAV1 and E-cadherin to unravel how co-expression of E-cadherin modulates CAV1 function in vitro and in vivo in WT C57BL/6 or Rag-/- immunodeficient mice and how a pro-inflammatory environment generated by treating cells with prostaglandin E2 (PGE2) alters CAV1 function in the presence of E-cadherin. CAV1 expression augmented migration, invasion, and metastasis of melanoma cells, and these effects were abolished via transient co-expression of E-cadherin. Importantly, exposure of cells to PGE2 reverted the effects of E-cadherin expression and increased CAV1 phosphorylation on tyrosine-14 and metastasis. Moreover, PGE2 administration blocked the ability of the CAV1/E-cadherin complex to prevent tumor formation. Therefore, our results support the notion that PGE2 can override the tumor suppressor potential of the E-cadherin/CAV1 complex and that CAV1 released from the complex is phosphorylated on tyrosine-14 and promotes migration/invasion/metastasis. These observations provide direct evidence showing how a pro-inflammatory environment caused here via PGE2 administration can convert a potent tumor suppressor complex into a promoter of malignant cell behavior.

Dataset: Impact of β-Galactosylceramidase Overexpression on the Protein Profile of Braf(V600E) Mutated Melanoma Cells

β-Galactosylceramidase (GALC) is a lysosomal enzyme involved in sphingolipid metabolism by removing β-galactosyl moieties from β-galactosyl ceramide and β-galactosyl sphingosine. Previous observations have shown that GALC exerts a pro-oncogenic activity in human melanoma. Here, the impact of GALC overexpression on the proteomic landscape of BRAF-mutated A2058 and A375 human melanoma cell lines was investigated by liquid chromatography–tandem mass spectrometry analysis of the cell extracts. The results indicate that GALC overexpression causes the upregulation/downregulation of 172/99 proteins in GALC-transduced cells when compared to control cells. Gene ontology categorization of up/down-regulated proteins indicates that GALC may modulate the protein landscape in BRAF-mutated melanoma cells by affecting various biological processes, including RNA metabolism, cell organelle fate, and intracellular redox status. Overall, these data provide further insights into the pro-oncogenic functions of the sphingolipid metabolizing enzyme GALC in human melanoma.

Synthesis, structure–activity relationship studies using density functional theory and in silico molecular docking on substituted benzohydrazide derivatives

The present study demonstrates the utility of benzohydrazide derivatives based on an approach to identify potential targets for a series of synthesized compounds that show potent anticancer activities against four cancer cell lines compared to other structurally related molecules. Benzohydrazide compounds have been synthesized effectively by the condensation of aldehyde and hydrazide at a 1:1 molar ratio. The complete series of compounds 1a-j were characterized by FT-IR, NMR, and one of them by single-crystal X-ray diffraction. The crystal structure of compound 1a shows a trans configuration around the CN bond and crystallized in a monoclinic system with C 2/c space group. All compounds exhibited good anticancer activity against four cancer cell lines such as A375 (human malignant melanoma), A549 (human lung adenocarcinoma), HT-29 (human epithelial intestinal) and MDA-MB-232(human metastatic breast). Among them, compound 1e shows the highest cytotoxic effect against the HT29 (IC50 = 0.47 µM) and A375 (IC50 = 0.80 µM) cell lines. Other compounds also exhibited promising anticancer activity. In addition, the nontoxic action was verified using the cytocompatibility assay on the L929 normal cell line and the hemolysis assay on human red blood cells. Parameters such as HOMO-LUMO energies, Hirshfeld surface analysis, and Molecular Electrostatic Potential (MEP) surface have been calculated using DFT and compared to experimental values of compounds 1a-c. In silico molecular docking studies revealed that the compound 1 h interacted very strongly with the 1T46 protein, with a docking score of −9.7 kcal/mol and very good binding via π–π, π-alkyl and π–σ interactions as compared to the standard drug. As a result of their potent cytotoxicity activities and computational analysis, these can be considered promising anticancer agents.