scholarly journals BRAFV600 inhibition alters the microRNA cargo in the vesicular secretome of malignant melanoma cells

2017 ◽  
Vol 114 (29) ◽  
pp. E5930-E5939 ◽  
Author(s):  
Taral R. Lunavat ◽  
Lesley Cheng ◽  
Berglind O. Einarsdottir ◽  
Roger Olofsson Bagge ◽  
Somsundar Veppil Muralidharan ◽  
...  
Keyword(s):  
Malignant Melanoma ◽  
Melanoma Cells ◽  
Resistant Cell ◽  
Resistant Cell Line ◽  
Braf Inhibitors ◽  
Braf Inhibition ◽  
Survival Pathway ◽  
Tumor Tissues

The BRAF inhibitors vemurafenib and dabrafenib can be used to treat patients with metastatic melanomas harboring BRAFV600 mutations. Initial antitumoral responses are often seen, but drug-resistant clones with reactivation of the MEK–ERK pathway soon appear. Recently, the secretome of tumor-derived extracellular vesicles (EVs) has been ascribed important functions in cancers. To elucidate the possible functions of EVs in BRAF-mutant melanoma, we determined the RNA content of the EVs, including apoptotic bodies, microvesicles, and exosomes, released from such cancer cells after vemurafenib treatment. We found that vemurafenib significantly increased the total RNA and protein content of the released EVs and caused significant changes in the RNA profiles. RNA sequencing and quantitative PCR show that cells and EVs from vemurafenib-treated cell cultures and tumor tissues harvested from cell-derived and patient-derived xenografts harbor unique miRNAs, especially increased expression of miR-211–5p. Mechanistically, the expression of miR-211–5p as a result of BRAF inhibition was induced by increased expression of MITF that regulates the TRPM1 gene resulting in activation of the survival pathway. In addition, transfection of miR-211 in melanoma cells reduced the sensitivity to vemurafenib treatment, whereas miR-211–5p inhibition in a vemurafenib resistant cell line affected the proliferation negatively. Taken together, our results show that vemurafenib treatment induces miR-211–5p up-regulation in melanoma cells both in vitro and in vivo, as well as in subsets of EVs, suggesting that EVs may provide a tool to understand malignant melanoma progression.

Epigenetic approaches to cancer therapy

2004 ◽  
Vol 32 (6) ◽  
pp. 1095-1097 ◽  
Author(s):  
J.A. Plumb ◽  
N. Steele ◽  
P.W. Finn ◽  
R. Brown
Keyword(s):  
Dna Methylation ◽  
Cell Line ◽  
Gene Promoter ◽  
Resistant Cell ◽  
Resistant Cell Line ◽  
Tumour Suppressor Genes ◽  
Control Of Gene Expression ◽  
Hmlh1 Gene

Histone deacetylation and DNA methylation have a central role in the control of gene expression, including transcriptional repression of tumour suppressor genes. Loss of DNA mismatch repair due to methylation of the hMLH1 gene promoter results in resistance to cisplatin in vitro and in vivo. The cisplatin-resistant cell line A2780/cp70 is 8-fold more resistant to cisplatin than the non-resistant cell line, and has the hMLH1 gene methylated. Treatment with an inhibitor of DNA methyltransferase, DAC (2-deoxy-5′-azacytidine), results in a partial reversal of DNA methylation, re-expression of MLH1 (mutL homologue 1) and sensitization to cisplatin both in vitro and in vivo. PXD101 is a novel hydroxamate type histone deacetylase inhibitor that shows antitumour activity in vivo and is currently in phase I clinical evaluation. Treatment of A2780/cp70 tumour-bearing mice with DAC followed by PXD101 results in a marked increase in the number of cells that re-express MLH1. Since the clinical use of DAC may be limited by toxicity and eventual re-methylation of genes, we suggest that the combination of DAC and PXD101 could have a role in increasing the efficacy of chemotherapy in patients with tumours that lack MLH1 expression due to hMLH1 gene promoter methylation.

Detection of the 170 kDa P-Glycoprotein in Neoplastic and Normal Tissues

1989 ◽  
Vol 75 (6) ◽  
pp. 542-546 ◽  
Author(s):  
Enrico Ronchi ◽  
Ornella Sanfilippo ◽  
Giovanni Di Fronzo ◽  
Maria Rosa Bani ◽  
Gabriella Della Torre ◽  
...  
Keyword(s):  
Protein A ◽  
Resistant Cell ◽  
Nodal Metastasis ◽  
Resistant Cell Line ◽  
Resistant Variant ◽  
Normal Tissues ◽  
Immunoblotting Assay ◽  
Human Solid Tumors

A membrane purification procedure and an immunoblotting assay have been designed to allow screening of human solid tumors for overexpression of the GP170 glycoprotein without employing a disaggregation method to obtain cell suspensions. The electrophoresed membrane proteins were probed, after Western Blotting, with the C219 monoclonal antibody and iodinated Protein A. The labeling intensity of the bands on the autoradioimmunoblots were quantified by densitometry. To test for the presence of GP170, we used membranes from the UV 2237 fibrosarcoma line and its adriamycin-resistant variant ADMR, grown in vitro or as solid tumor in mice. Membranes of human normal and tumor tissues obtained from previously untreated patients were also tested. An immunoreaction was observed in the adriamycin-resistant UV 2237 lines grown in vitro or in vivo. Quantitatively, the binding of the resistant cell line grown in vitro was higher than that observed in cells grown in mice. Bands in the GP 170 region were observed in 4/7 normal and in 7/7 tumor colon tissues and in the normal medulla from 2 patients with cancer of the renal cortex. No reaction could be found in samples from normal tissue, primary tumor or nodal metastasis from 7 patients with breast cancer.

scholarly journals Treatment of melanoma cells with the synthetic retinoid CD437 induces apoptosis via activation of AP-1 in vitro, and causes growth inhibition in xenografts in vivo.

1996 ◽  
Vol 135 (6) ◽  
pp. 1889-1898 ◽  
Author(s):  
D Schadendorf ◽  
M A Kern ◽  
M Artuc ◽  
H L Pahl ◽  
T Rosenbach ◽  
...  
Keyword(s):  
Cell Death ◽  
Malignant Melanoma ◽  
Programmed Cell Death ◽  
Melanoma Cells ◽  
Human Melanoma ◽  
Mrna Levels ◽  
Synthetic Retinoid ◽  
Human Melanoma Cells

Human malignant melanoma is notoriously resistant to pharmacological modulation. We describe here for the first time that the synthetic retinoid CD437 has a strong dose-dependent antiproliferative effect on human melanoma cells (IC50: 5 x 10(-6) M) via the induction of programmed cell death, as judged by analysis of cell morphology, electron microscopical features, and DNA fragmentation. Programmed cell death was preceded by a strong activation of the AP-1 complex in CD437-treated cells as demonstrated by gel retardation and chloramphenicol transferase (CAT) assays. Northern blot analysis showed a time-dependent increase in the expression of c-fos and c-jun encoding components of AP-1, whereas bcl-2 and p53 mRNA levels remained constant. CD437 also exhibited a strong growth inhibitory effect on MeWo melanoma cells in a xenograft model. In tissue sections of CD437-treated MeWo tumors from these animals, apoptotic melanoma cells and c-fos overexpressing cells were colocalized by TdT-mediated deoxyuridine triphosphate-digoxigenin nick end labeling (TUNEL) staining and in situ hybridization. Taken together, this report identifies CD437 as a retinoid that activates and upregulates the transcription factor AP-1, leading eventually to programmed cell death of exposed human melanoma cells in vitro and in vivo. Further studies are needed to evaluate whether synthetic retinoids such as CD437 represent a new class of retinoids, which may open up new ways to a more effective therapy of malignant melanoma.

scholarly journals Capsaicin Exerts Therapeutic Effects by targeting tNOX-SIRT1 Axis and Augmenting ROS-Dependent Cytotoxic Autophagy in Melanoma Cancer Cells

2020 ◽  
Author(s):  
Atikul Islam ◽  
Pei-Fang Hsieh ◽  
Jou-Chun Chou ◽  
Jiunn-Wang Liao ◽  
Ming-Kun Hsieh ◽  
...  
Keyword(s):  
Malignant Melanoma ◽  
Cancer Cells ◽  
Nadh Oxidase ◽  
Treatment Options ◽  
Melanoma Cells ◽  
Therapeutic Effects ◽  
Melanoma Cancer ◽  
Anticancer Properties

Abstract Background: Although considered a rare form of skin cancer, malignant melanoma has steadily increased internationally and is a main cause of cancer-associated death worldwide. The treatment options for malignant melanoma are very limited. Accumulating data suggest that the natural compound, capsaicin, exhibits preferential anticancer properties to act as a nutraceutical agent. Here, we explored the underlying molecular events involved in the inhibitory effects of capsaicin on the growth of melanoma cells.Methods: The cellular thermal shift assay (CETSA) and isothermal dose response fingerprint (ITDRFCETSA) were utilized to validate the binding of capsaicin with the tumor-associated NADH oxidase, tNOX (ENOX2) in melanoma cells. We also assessed the cellular impact of capsaicin-targeting of tNOX on A375 cells by flow cytometry and protein analysis. The essential role of tNOX in tumor- and melanoma-growth limiting abilities of capsaicin was evaluated in C57BL/6 mice.Results: Our data show that capsaicin directly targets cellular tNOX to inhibit its enzymatic activity and enhance protein degradation capacity. The inhibition of tNOX by capsaicin is accompanied by the attenuation of SIRT1, a NAD+-dependent deacetylase that enhances ULK1 acetylation to induce ROS-dependent autophagy in melanoma cells. Capsaicin treatment of mice implanted with melanoma cancer cells suppressed tumor growth by down-regulating tNOX and SIRT1, which was also seen in an in vivo xenograft study with tNOX-depleted melanoma cells. Conclusions: Together, our findings suggest that tNOX expression is important for the growth of melanoma cancer cells both in vitro and in vivo, and that inhibition of the tNOX-SIRT1 axis contributes to inducting cytotoxic ROS-dependent autophagy in melanoma cells.

The proteasome inhibitor bortezomib inhibits the growth of canine malignant melanoma cells in vitro and in vivo

2013 ◽  
Vol 198 (3) ◽  
pp. 577-582 ◽  
Author(s):  
Keita Ito ◽  
Masato Kobayashi ◽  
Shiori Kuroki ◽  
Yu Sasaki ◽  
Taisuke Iwata ◽  
...  
Keyword(s):  
Malignant Melanoma ◽  
Proteasome Inhibitor ◽  
Melanoma Cells

Luteolin inhibits proliferation and induces apoptosis of human melanoma cells in vivo and in vitro by suppressing MMP-2 and MMP-9 through the PI3K/AKT pathway

2019 ◽  
Vol 10 (2) ◽  
pp. 703-712 ◽  
Author(s):  
Xin Yao ◽  
Wei Jiang ◽  
Danhong Yu ◽  
Zhaowei Yan
Keyword(s):  
Malignant Melanoma ◽  
Incidence Rate ◽  
Melanoma Cell ◽  
Melanoma Cells ◽  
Human Melanoma ◽  
Akt Pathway ◽  
Human Melanoma Cells ◽  
Cell Metastasis

Since the incidence rate of malignant melanoma is increasing annually, development of drugs against melanoma cell metastasis has become more urgent.

scholarly journals Non-canonical AR activity facilitates endocrine resistance in breast cancer

2019 ◽  
Vol 26 (2) ◽  
pp. 251-264 ◽  
Author(s):  
KeeMing Chia ◽  
Heloisa Milioli ◽  
Neil Portman ◽  
Geraldine Laven-Law ◽  
Rhiannon Coulson ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Clinical Trials ◽  
Endocrine Resistance ◽  
Resistant Cell ◽  
Resistant Cell Line ◽  
Breast Cancer Cell Lines ◽  
Microarray Gene Expression ◽  
Pdx Model

The role of androgen receptor (AR) in endocrine-resistant breast cancer is controversial and clinical trials targeting AR with an AR antagonist (e.g., enzalutamide) have been initiated. Here, we investigated the consequence of AR antagonism using in vitro and in vivo models of endocrine resistance. AR antagonism in MCF7-derived tamoxifen-resistant (TamR) and long-term estrogen-deprived breast cancer cell lines were achieved using siRNA-mediated knockdown or pharmacological inhibition with enzalutamide. The efficacy of enzalutamide was further assessed in vivo in an estrogen-independent endocrine-resistant patient-derived xenograft (PDX) model. Knockdown of AR inhibited the growth of the endocrine-resistant cell line models. Microarray gene expression profiling of the TamR cells following AR knockdown revealed perturbations in proliferative signaling pathways upregulated in endocrine resistance. AR loss also increased some canonical ER signaling events and restored sensitivity of TamR cells to tamoxifen. In contrast, enzalutamide did not recapitulate the effect of AR knockdown in vitro, even though it inhibited canonical AR signaling, which suggests that it is the non-canonical AR activity that facilitated endocrine resistance. Enzalutamide had demonstrable efficacy in inhibiting AR activity in vivo but did not affect the growth of the endocrine-resistant PDX model. Our findings implicate non-canonical AR activity in facilitating an endocrine-resistant phenotype in breast cancer. Unlike canonical AR signaling which is inhibited by enzalutamide, non-canonical AR activity is not effectively antagonized by enzalutamide, and this has important implications in the design of future AR-targeted clinical trials in endocrine-resistant breast cancer.

scholarly journals GSK1838705a, an IGF-1R/ALK Inhibitor, Overcomes Resistance to Crizotinib in ALK-Positive ALCL

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4069-4069
Author(s):  
Wenyu Shi ◽  
Jian-Yong Li
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Large Cell ◽  
Resistant Cell ◽  
Resistant Cell Line ◽  
Expression Level ◽  
Downstream Signaling ◽  
Single Drug

Anaplastic large cell lymphoma (ALCL) is a type of CD30-expressing non-Hodgkin's lymphoma (NHL), which accounts for 2% to 3% of adult non-Hodgkin's lymphoma,accounting for 15% to 30% of children with large cell lymphoma. Anaplastic lymphoma kinase (ALK) positive ALCL is highly invasive, and currently it is generally based on CHOP combined with chemotherapy. The proportion of patients with complete relief of symptoms is as high as 90%, but the proportion of recurrence is also as high as 40%. Crizotinib is the first generation of ALK inhibitors that have been approved for the treatment of ALK+ ALCL. Unfortunately, most patients treated with crizotinib relapse after a significant initial response. The median progression-free survival of clinical trials was 10.5 months. Various mutations in the ALK kinase domain and amplification of the ALK gene copy number, activation of the alternative pathway, and tumor heterogeneity are major causes of crizotinib resistance. Studies have shown that IGF-1R interacts with NPM-ALK to promote ALK+ALCL transformation, proliferation and migration. GSK is a small molecule kinase inhibitor that inhibits both IGF-IR and ALK. Therefore, GSK with simultaneous inhibition of the bidirectional potential of IGF-IR and ALK has a promising prospect in the targeted therapy of NPM-ALK+ALCL. This study explored the inhibitory effects of GSK on NPM-ALK+ALCL and crizotinib-resistant NPM-ALK+ALCL by in vivo and in vitro experiments. In vitro experiments: The sensitivity of ALCL cell line to GSK1838705a was detected by CCK8 and flow cytometry. The expression of phosphorylation of IGF-1R and NPM-ALK signaling pathway in Karpas299 and SR786 cell lines stimulated by GSK was detected by WB method. In order to study the crizotinib resistance mutation, we established ALK+ALCL crizotinib-resistant cell lines Karpas299-R and SR786-R, and identified the resistance of Karpas299-R and SR786-R cell lines by CCK8 and flow cytometry. The drug-resistant and non-resistant strains were stimulated with gradient concentrations of crizotinib and gradient GSK, and the IC50 of the two were compared by CCK8. The WB method was used to compare the phosphorylation levels of downstream signaling pathways in drug-resistant and non-resistant strains. In vivo experiment: The ALK+ALCL and resistant-ALK+ALCL mouse model was established, and three groups of mice treated with control, GSK single drug 30 mg/kg, GSK single drug 60 mg/kg, were established. The tumor volume and body weight of the four groups were compared. Immunohistochemistry was used to compare the expression levels of key signaling molecules and apoptotic proteins in each group. SPSS statistical software draws survival curves. As the concentration of GSK gradually increases, the survival rate of ALCL cells gradually decreases. The expression of pIGF-1R, pNPM-ALK, pSTAT3, pAKT, casepase3 and other molecules decreased in the downstream signaling pathway, and the expression level of cleaved-casepase3 increased.In the crizotinib-resistant cell line, with the increase of the concentration of GSK, the apoptosis rate of the cells increased and the phosphorylation level of the downstream molecules gradually decreased. Tumor volume of three groups of mouse models: control>GSK single drug 30 mg/kg>GSK single drug 60 mg/kg. Immunohistochemistry results showed that the expression level of key signaling molecules in GSK-treated CHOP-treated mice decreased, and the expression level of apoptotic proteins increased. In this research, we explored the effects of GSK1838705A on proliferation, apoptosis, and clonogenesis of ALCL cell lines. Subsequently, we established a crizotinib-resistant cell line and noticed that GSK1838705A can effectively reduce the viability of resistant ALCL cells and significantly restrain the transmission of downstream survival signaling pathways induced by IGF1R/IR phosphorylation. Besides, we discovered that GSK1838705A inhibited the development of both crizotinib-sensitive and crizotinib-resistant ALCL tumors in the ALCL mouse model established by subcutaneous tumorigenesis. Based on the results of previous clinical trials, we put forward to use GSK1838705A as an alternative treatment strategy to overcome crizotinib-resistant ALCL. Disclosures No relevant conflicts of interest to declare.

scholarly journals Functional Implication of Netrin Expression in Malignant Melanoma

2009 ◽  
Vol 31 (6) ◽  
pp. 415-422
Author(s):  
Simone Kaufmann ◽  
Silke Kuphal ◽  
Thomas Schubert ◽  
Anja K. Bosserhoff
Keyword(s):  
Malignant Melanoma ◽  
Melanoma Cells ◽  
Transcriptional Level ◽  
Altered Expression ◽  
Invasion And Migration ◽  
Expression Of Genes ◽  
Functional Relevance ◽  
And Migration

Background: Malignant melanoma cells are known to have altered expression of genes supporting proliferation and invasion, however, the expression of molecules of the Netrin family of repellent factors has not been analyzed in melanomas until now.Results: Here, we show that Netrin-1 expression is strongly induced in melanoma cells compared to melanocytes in vivo and in vitro controlled at the transcriptional level via ETS-1. In addition, the expression of the netrin receptor UNC5B was induced and that of UNC5C was reduced in the tumor cells. In order to determine the functional relevance of Netrin-1 expression in malignant melanoma, Netrin expression in melanoma cells was reduced by siRNA attempts and primary human melanocytes were treated with recombinant Netrin-1. The cells showed no changes in proliferation or apoptosis, however, a strong reduction of migratory properties was observed in the melanoma cells after reduction of Netrin expression whereas melanocyte migration was strongly induced by treatment with Netrin.Conclusions: Our study suggests that Netrin-1 promotes melanoma cell invasion and migration and therefore has an important role in the progression of malignant melanoma.

scholarly journals P2X7 promotes metastatic spreading and triggers release of miRNA-containing exosomes and microvesicles from melanoma cells

2021 ◽  
Vol 12 (12) ◽  
Author(s):  
Anna Pegoraro ◽  
Elena De Marchi ◽  
Manuela Ferracin ◽  
Elisa Orioli ◽  
Michele Zanoni ◽  
...  
Keyword(s):  
Malignant Melanoma ◽  
Melanoma Cell ◽  
P2x7 Receptor ◽  
Metastatic Malignant Melanoma ◽  
Melanoma Cells ◽  
Vesicular Release ◽  
And Migration ◽  
Metastatic Spreading

AbstractTumor growth and metastatic spreading are heavily affected by the P2X7 receptor as well as microvesicles and exosomes release into the tumor microenvironment. P2X7 receptor stimulation is known to trigger vesicular release from immune and central nervous system cells. However, P2X7 role in microvesicles and exosomes delivery from tumor cells was never analyzed in depth. Here we show that P2X7 is overexpressed in patients affected by metastatic malignant melanoma and that its expression closely correlates with reduced overall survival. Antagonism of melanoma cell-expressed P2X7 receptor inhibited in vitro anchorage-independent growth and migration and in vivo dissemination and lung metastasis formation. P2X7 stimulation triggered the release of miRNA-containing microvesicles and exosomes from melanoma cells, profoundly altering the nature of their miRNA content, as well as their dimensions and quantity. Among the more than 200 miRNAs that we found up-or-down-modulated for each vesicular fraction tested, we identified three miRNAs, miR-495-3p, miR-376c-3p, and miR-6730-3p, that were enriched in both the exosome and microvesicle fraction in a P2X7-dependent fashion. Interestingly, upon transfection, these miRNAs promoted melanoma cell growth or migration, and their vesicular release was minimized by P2X7 antagonism. Our data unveil an exosome/microvesicle and miRNA-dependent mechanism for the pro-metastatic activity of the P2X7 receptor and highlight this receptor as a suitable prognostic biomarker and therapeutic target in malignant melanoma.

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