MSH binding in bomirski amelanotic hamster melanoma cells is stimulated by L-tyrosine

1987 ◽  
Vol 7 (12) ◽  
pp. 949-954 ◽  
Author(s):  
Andrzej Slominski ◽  
John Pawelek
Keyword(s):  
Culture Medium ◽  
De Novo ◽  
Binding Capacity ◽  
Fold Increase ◽  
Insulin Binding ◽  
Melanoma Cells ◽  
Amelanotic Melanoma ◽  
Tyrosinase Activity ◽  
Regulatory Pathways ◽  
Hamster Melanoma

Bomirski Ab amelanotic melanoma cells have recently been shown to undergo striking phenotypic changes when precursors of the melanogenic pathway, L-tyrosine and L-dopa, are added to the culture medium. The changes include increased tyrosinase activity and de novo synthesis of melanosomes and melanin. L-tyrosine and L-dopa appeared to elicit these responses through separate but overlapping regulatory pathways. Here we show an additional effect of L-tyrosine: stimulation of MSH binding capacity. Cells cultured for 24–48 hours in the presence of 200 μM L-tyrosine display a 3–4 fold increase in their ability to bind125l-β-MSH. L-dopa did not stimulate MSH binding under the same conditions. In control experiments neither L-tyrosine nor L-dopa had any effect on insulin binding. The amelanotic cells respond to MSH with increased dendrite formation, increased tyrosinase activity without melanin production, and decreased growth rate.

MSH inhibits growth in a line of amelanotic hamster melanoma cells and induces increases in cyclic AMP levels and tyrosinase activity without inducing melanogenesis

1989 ◽  
Vol 92 (4) ◽  
pp. 551-559
Author(s):  
A. Slominski ◽  
G. Moellmann ◽  
E. Kuklinska
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Melanoma Cells ◽  
Amelanotic Melanoma ◽  
Tyrosinase Activity ◽  
Melanin Synthesis ◽  
Melanocyte Stimulating Hormone ◽  
Inhibit Cell Growth ◽  
Hamster Melanoma ◽  
Peak Increase

In Bomirski Ab amelanotic hamster melanoma cells, L-tyrosine and/or L-dopa induce increases in tyrosinase activity as well as synthesis of melanosomes and melanin. L-tyrosine also modifies melanocyte-stimulating hormone (MSH) binding. In this paper we show that in the Bomirski amelanotic melanoma system MSH and agents that raise intracellular cyclic AMP induce dendrite formation, inhibit cell growth, and cause substantial increases in tyrosinase activity without inducing melanin synthesis. Tyrosinase activity is detected only in broken cell preparations, or cytochemically in fixed cells. In the continued absence of mature melanosomes, the induced enzyme remains in elements of the trans-Golgi reticulum. Comparative measurements of cyclic AMP in amelanotic and tyrosine-induced melanotic cells show similar basal levels. L-tyrosine and L-dopa have little or no effect, whereas MSH may cause a 1000% peak increase in cyclic AMP levels both in amelanotic and melanotic cells. None of these agents influences cyclic GMP or inositol trisphosphate (InsP3) levels. In agreement with the InsP3 assays, phorbol ester (TPA) has no effect on melanization, tyrosinase activity or cell proliferation. In conclusion, in the Bomirski amelanotic melanoma, MSH induces only partial cell differentiation associated with raised levels of cyclic AMP. Induction of melanosome synthesis and melanization by L-tyrosine or L-dopa appear to follow pathways unrelated to cyclic AMP, cyclic GMP or InsP3.

L-Tyrosine stimulates induction of tyrosinase activity by MSH and reduces cooperative interactions between MSH receptors in hamster melanoma cells

1989 ◽  
Vol 9 (5) ◽  
pp. 579-586 ◽  
Author(s):  
Andrzej Slominski ◽  
Pawel Jastreboff ◽  
John Pawelek
Keyword(s):  
Cell Lines ◽  
Melanoma Cell ◽  
Binding Capacity ◽  
Melanoma Cells ◽  
Tyrosinase Activity ◽  
Receptor Activity ◽  
Cooperative Interactions ◽  
Cellular Responsiveness ◽  
Hamster Melanoma ◽  
Melanoma Cell Lines

L-tyrosine, a precurosr to melanin, has recently been shown to be a regulator of the melanogenic pathway in some cultured melanoma cell lines. In this paper we demonstrated that L-tyrosine, besides increasing binding capacity for MSH, decreased cooperativity between MSH receptors and increased the level of tyrosinase induction by MSH. Apparently, regulation of MSH receptor activity by L-tyrosine involves specific changes in the interactions between the receptors and modification of the cellular responsiveness to MSH.

Tyrosinase activity in primary cell culture of amelanotic melanoma cells

1983 ◽  
Vol 3 (11) ◽  
pp. 1027-1034 ◽  
Author(s):  
A. Słomiński ◽  
P. W. D. Scisłowski ◽  
A. Bomirski
Keyword(s):  
Gel Electrophoresis ◽  
Primary Cell Culture ◽  
Soluble Fraction ◽  
Calf Serum ◽  
Melanoma Cells ◽  
Amelanotic Melanoma ◽  
Tyrosinase Activity ◽  
Logarithmic Phase

After transfer of the Ab amelanotic melanoma cells from in vivo to in vitro growth conditons tyrosinase activity in their soluble fraction rapidly increased. This increase lasted to the middle of the logarithmic phase of growth and was followed by a decrease of tyrosinase activity, which was accompanied by accumulation of melanin in the cells. Calf serum stimulated simul-taneously tyrosinase activity, melanin synthesis, and proliferation of the melanoma ceils. Acrylamide-gel electrophoresis patterns of soluble tyrosinase from the Ab melanoma cells cultured in vitro consisted of two bands, similarly as soluble tyrosinase from the Ma melanotic melanoma cells freshly isolated from solid tumors.

scholarly journals Melanization of Bomirski hamster amelanotic melanoma cells (Ab line) depends on the type of culture medium

2019 ◽  
Vol 56 (4) ◽  
pp. 207-214
Author(s):  
Aneta Skoniecka ◽  
Agata Zauszkiewicz-Pawlak ◽  
Agata Tyminska ◽  
Miroslawa Cichorek
Keyword(s):  
Culture Medium ◽  
Melanoma Cells ◽  
Amelanotic Melanoma

scholarly journals Glucocorticoids increase insulin binding and the amount of insulin-receptor mRNA in human cultured lymphocytes

1988 ◽  
Vol 249 (3) ◽  
pp. 715-719 ◽  
Author(s):  
Y Shibasaki ◽  
H Sakura ◽  
M Odawara ◽  
M Shibuya ◽  
Y Kanazawa ◽  
...  
Keyword(s):  
Cell Surface ◽  
Insulin Receptor ◽  
De Novo ◽  
Insulin Receptors ◽  
Fold Increase ◽  
Insulin Binding ◽  
Dependent Manner ◽  
Receptor Mrna ◽  
Dose Dependent ◽  
Receptor Mrnas

The effect of steroid hormones on insulin binding and the amount of insulin-receptor mRNA was examined in IM-9 lymphocytes. Cortisol and cortexolone, but not oestrogen, increased both the binding of insulin and the amount of insulin-receptor mRNA in a time- and dose-dependent manner. Cortisol was most potent, and induced a 2-fold increase in insulin binding and a 4-fold increase in mRNA. The elevation in binding was due to an increased number of insulin receptors at the cell surface. The increase in mRNA involved all four of the insulin-receptor mRNAs and could not be inhibited by cycloheximide. The cortisol-induced increase in mRNA was associated with a 3-4-fold increase in the synthesis of pro-receptor. The relative potency of the three steroids indicated that these effects were mediated by an interaction with the glucocorticoid receptor. The results of this study suggest that cortisol can increase the number of insulin receptors at the cell surface by increasing the amounts of insulin-receptor mRNA and the synthesis de novo of insulin receptors.

scholarly journals Novel Chemically Modified Curcumin (CMC) Derivatives Inhibit Tyrosinase Activity and Melanin Synthesis in B16F10 Mouse Melanoma Cells

Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 674
Author(s):  
Shilpi Goenka ◽  
Francis Johnson ◽  
Sanford R. Simon
Keyword(s):  
Enzyme Activity ◽  
Parent Compound ◽  
Radical Scavenging ◽  
Melanoma Cells ◽  
Tyrosinase Activity ◽  
Partial Recovery ◽  
Tyrosinase Inhibitor ◽  
Pyrocatechol Violet ◽  
Mouse Melanoma ◽  
Chemically Modified

Skin hyperpigmentation disorders arise due to excessive production of the macromolecular pigment melanin catalyzed by the enzyme tyrosinase. Recently, the therapeutic use of curcumin for inhibiting tyrosinase activity and production of melanin have been recognized, but poor stability and solubility have limited its use, which has inspired synthesis of curcumin analogs. Here, we investigated four novel chemically modified curcumin (CMC) derivatives (CMC2.14, CMC2.5, CMC2.23 and CMC2.24) and compared them to the parent compound curcumin (PC) for inhibition of in vitro tyrosinase activity using two substrates for monophenolase and diphenolase activities of the enzyme and for diminution of cellular melanogenesis. Enzyme kinetics were analyzed using Lineweaver-Burk and Dixon plots and nonlinear curve-fitting to determine the mechanism for tyrosinase inhibition. Copper chelating activity, using pyrocatechol violet dye indicator assay, and antioxidant activity, using a DPPH radical scavenging assay, were also conducted. Next, the capacity of these derivatives to inhibit tyrosinase-catalyzed melanogenesis was studied in B16F10 mouse melanoma cells and the mechanisms of inhibition were elucidated. Inhibition mechanisms were studied by measuring intracellular tyrosinase activity, cell-free and intracellular α-glucosidase enzyme activity, and effects on MITF protein level and cAMP maturation factor. Our results showed that CMC2.24 showed the greatest efficacy as a tyrosinase inhibitor of all the CMCs and was better than PC as well as a popular tyrosinase inhibitor-kojic acid. Both CMC2.24 and CMC2.23 inhibited tyrosinase enzyme activity by a mixed mode of inhibition with a predominant competitive mode. In addition, CMC2.24 as well as CMC2.23 showed a comparable robust efficacy in inhibiting melanogenesis in cultured melanocytes. Furthermore, after removal of CMC2.24 or CMC2.23 from the medium, we could demonstrate a partial recovery of the suppressed intracellular tyrosinase activity in the melanocytes. Our results provide a proof-of-principle for the novel use of the CMCs that shows them to be far superior to the parent compound, curcumin, for skin depigmentation.

scholarly journals Inhibition Effect of Chloroquine and Integrin-Linked Kinase Knockdown on Translation in Melanoma Cells

2021 ◽  
Vol 22 (7) ◽  
pp. 3682
Author(s):  
Dorota Gil ◽  
Piotr Laidler ◽  
Marta Zarzycka ◽  
Joanna Dulińska-Litewka
Keyword(s):  
Signaling Pathways ◽  
Melanoma Cell ◽  
Melanoma Cells ◽  
Antitumor Effects ◽  
Regulatory Pathways ◽  
Scratch Wound ◽  
Integrin Linked Kinase ◽  
And Migration ◽  
Cell Signaling Pathways

The twofold role of autophagy in cancer is often the therapeutic target. Numerous regulatory pathways are shared between autophagy and other molecular processes needed in tumorigenesis, such as translation or survival signaling. Thus, we have assumed that ILK knockdown should promote autophagy, and used together with chloroquine, an autophagy inhibitor, it could generate a better anticancer effect by dysregulation of common signaling pathways. Expression at the protein level was analyzed using Western Blot; siRNA transfection was done for ILK. Analysis of cell signaling pathways was monitored with phospho-specific antibodies. Melanoma cell proliferation was assessed with the crystal violet test, and migration was evaluated by scratch wound healing assays. Autophagy was monitored by the accumulation of its marker, LC3-II. Our data show that ILK knockdown by siRNA suppresses melanoma cell growth by inducing autophagy through AMPK activation, and simultaneously initiates apoptosis. We demonstrated that combinatorial treatment of melanoma cells with CQ and siILK has a stronger antitumor effect than monotherapy with either of these. It generates the synergistic antitumor effects by the decrease of translation of both global and oncogenic proteins synthesis. In our work, we point to the crosstalk between translation and autophagy regulation.

scholarly journals In Vitro Anticancer Potential of Jasione montana and Its Main Components Against Human Amelanotic Melanoma Cells

2021 ◽  
Vol 22 (7) ◽  
pp. 3345
Author(s):  
Aleksandra Maria Juszczak ◽  
Robert Czarnomysy ◽  
Jakub Władysław Strawa ◽  
Marijana Zovko Končić ◽  
Krzysztof Bielawski ◽  
...  
Keyword(s):  
Cell Line ◽  
Melanoma Cell ◽  
Melanoma Cell Line ◽  
Binding Assay ◽  
Annexin V ◽  
Melanoma Cells ◽  
Amelanotic Melanoma ◽  
Cytotoxic Activities ◽  
Ionization Mass ◽  
Caspase 9

Jasione montana L. (Campanulaceae) is used in traditional Belarusian herbal medicine for sleep disorders in children, but the chemical composition and biological activity have not been investigated. In this study, the activities of J. montana extracts, their fractions and main compounds were evaluated in amelanotic melanoma C32 (CRL-1585) cells and normal fibroblasts (PCS-201-012). The extracts and fractions were analyzed using liquid chromatography–photodiode array detection–electrospray ionization–mass spectrometry (LC–PDA–ESI–MS/TOF) to characterize 25 compounds. Further, three major and known constituents, luteolin (22) and its derivatives such as 7-O-glucoside (12) and 7-O-sambubioside (9) were isolated and identified. The cytotoxic activities against fibroblasts and the amelanotic melanoma cell line were determined using the fixable viability stain (FVS) assay. The influence of diethyl ether (Et2O) fraction (JM4) and 22 on apoptosis induction was investigated using an annexin V binding assay. The obtained results showed significant cytotoxicity of JM4 and 22 with IC50 values of 119.7 ± 3.2 and 95.1 ± 7.2 μg/mL, respectively. The proapoptotic potential after 22 treatment in the C32 human amelanotic melanoma cell line was comparable to that of vinblastine sulfate (VLB), detecting 29.2 ± 3.0% apoptotic cells. Moreover, 22 displayed less necrotic potential against melanoma cells than VLB. In addition, the influences of JM4 and 22 on the dysfunction of the mitochondrial membrane potential (MMP), cell cycle and activity of caspases 3, 8, 9, and 10 were established. The effects of JM4 on MMP change (74.5 ± 3.0% of the cells showed a reduced MMP) corresponded to the results obtained from the annexin V binding assay and activation of caspase-9. JM4 and 22 displayed a significant impact on caspase-9 (40.9 ± 2.4% of the cells contained active caspase-9 after JM4 treatment and 16.6 ± 0.8% after incubation with 22) and the intrinsic (mitochondrial) apoptotic pathway. Moreover, studies have shown that JM4 and 22 affect the activation of external apoptosis pathways by inducing the caspase-8 and caspase-10 cascades. Thus, activation of caspase-3 and DNA damage via external and internal apoptotic pathways were observed after treatment with JM4 and 22. The obtained results suggest that J. montana extracts could be developed as new topical preparations with potential anticancer properties due to their promising cytotoxic and proapoptotic potential.

scholarly journals Expression Signatures of microRNAs and Their Targeted Pathways in the Adipose Tissue of Chickens during the Transition from Embryonic to Post-Hatch Development

Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 196
Author(s):  
Julie A. Hicks ◽  
Hsiao-Ching Liu
Keyword(s):  
Energy Source ◽  
Adipose Tissue ◽  
De Novo ◽  
Lipid Storage ◽  
Storage Site ◽  
Metabolic Processes ◽  
Metabolic Switch ◽  
Regulatory Pathways ◽  
Main Site ◽  
Real Time Quantitative Pcr

As the chick transitions from embryonic to post-hatching life, its metabolism must quickly undergo a dramatic switch in its major energy source. The chick embryo derives most of its energy from the yolk, a lipid-rich/carbohydrate-poor source. Upon hatching, the chick’s metabolism must then be able to utilize a lipid-poor/carbohydrate-rich source (feed) as its main form of energy. We recently found that a number of hepatically-expressed microRNAs (miRNAs) help facilitate this shift in metabolic processes in the chick liver, the main site of lipogenesis. While adipose tissue was initially thought to mainly serve as a lipid storage site, it is now known to carry many metabolic, endocrine, and immunological functions. Therefore, it would be expected that adipose tissue is also an important factor in the metabolic switch. To that end, we used next generation sequencing (NGS) and real-time quantitative PCR (RT-qPCR) to generate miRNome and transcriptome signatures of the adipose tissue during the transition from late embryonic to early post-hatch development. As adipose tissue is well known to produce inflammatory and other immune factors, we used SPF white leghorns to generate the initial miRNome and transcriptome signatures to minimize complications from external factors (e.g., pathogenic infections) and ensure the identification of bona fide switch-associated miRNAs and transcripts. We then examined their expression signatures in the adipose tissue of broilers (Ross 708). Using E18 embryos as representative of pre-switching metabolism and D3 chicks as a representative of post-switching metabolism, we identified a group of miRNAs which work concordantly to regulate a diverse but interconnected group of developmental, immune and metabolic processes in the adipose tissue during the metabolic switch. Network mapping suggests that during the first days post-hatch, despite the consumption of feed, the chick is still heavily reliant upon adipose tissue lipid stores for energy production, and is not yet efficiently using their new energy source for de novo lipid storage. A number of core master regulatory pathways including, circadian rhythm transcriptional regulation and growth hormone (GH) signaling, likely work in concert with miRNAs to maintain an essential balance between adipogenic, lipolytic, developmental, and immunological processes in the adipose tissue during the metabolic switch.

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