scholarly journals Effects of Growth Hormone in Human Melanoma Drug Resistance

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A1016-A1016
Author(s):  
Pranay Arora ◽  
Reetobrata Basu ◽  
John Joseph Kopchick
Keyword(s):  
Growth Hormone ◽  
Growth Hormone Receptor ◽  
Molecular Mechanisms ◽  
Melanoma Cells ◽  
Human Melanoma ◽  
Mouse Tumor ◽  
Gh Treatment ◽  
Mesenchymal Transition

Abstract Melanoma, an extremely drug resistant form of cancer, displays elevated levels of growth hormone (GH) and growth hormone receptor (GHR) expression. We have described a GH dependent mechanism of chemoresistance in melanoma through a series of earlier studies. In GHR overexpressing human melanoma, GH action drives active drug efflux and phenotype switching by upregulating ATP-binding cassette transporters (ABC-transporters) and epithelial-to-mesenchymal transition (EMT) markers. Inhibition of GHR activation reverses these effects, increases drug retention, and sensitizes the melanoma cells to chemotherapy. GH action in melanoma also appears to drive drug sequestration in melanosomes as we present here. GH action was found to modulate the levels of melanocyte-inducing transcription factor (MITF), the master regulator of melanosome synthesis and melanoma. Additionally, MITF target gene levels and drug sequestering ABC transporter expression were also elevated by GH treatment in vitro and in vivo in mouse tumor xenografts. This was corroborated by in silico analyses of tumor databases. Furthermore, we observed a dose dependent increase in tyrosinase activity and melanogenesis in human melanoma cells with GH, in the presence of chemotherapy, which was suppressed by siRNA mediated GHR inhibition. Thus, we describe an array of molecular mechanisms by which GH drives chemoresistance in melanoma. Therefore, GHR inhibition combined with chemotherapy should lead to better tumor clearance and improve overall survival.

scholarly journals Growth Hormone Upregulates Mediators of Melanoma Drug Efflux and Epithelial-to-Mesenchymal Transition In Vitro and In Vivo

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3640
Author(s):  
Yanrong Qian ◽  
Reetobrata Basu ◽  
Samuel C. Mathes ◽  
Nathan A. Arnett ◽  
Silvana Duran-Ortiz ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Epithelial To Mesenchymal Transition ◽  
Human Melanoma ◽  
Drug Efflux ◽  
Mesenchymal Transition ◽  
Mouse Melanoma ◽  
Wide Range ◽  
Mouse Lines

Growth hormone (GH) and the GH receptor (GHR) are expressed in a wide range of malignant tumors including melanoma. However, the effect of GH/insulin-like growth factor (IGF) on melanoma in vivo has not yet been elucidated. Here we assessed the physical and molecular effects of GH on mouse melanoma B16-F10 and human melanoma SK-MEL-30 cells in vitro. We then corroborated these observations with syngeneic B16-F10 tumors in two mouse lines with different levels of GH/IGF: bovine GH transgenic mice (bGH; high GH, high IGF-1) and GHR gene-disrupted or knockout mice (GHRKO; high GH, low IGF-1). In vitro, GH treatment enhanced mouse and human melanoma cell growth, drug retention and cell invasion. While the in vivo tumor size was unaffected in both bGH and GHRKO mouse lines, multiple drug-efflux pumps were up regulated. This intrinsic capacity of therapy resistance appears to be GH dependent. Additionally, epithelial-to-mesenchymal transition (EMT) gene transcription markers were significantly upregulated in vivo supporting our current and recent in vitro observations. These syngeneic mouse melanoma models of differential GH/IGF action can be valuable tools in screening for therapeutic options where lowering GH/IGF-1 action is important.

scholarly journals Operative ubiquitin-specific protease 22 deubiquitination confers a more invasive phenotype to cholangiocarcinoma

2021 ◽  
Vol 12 (7) ◽  
Author(s):  
Yu Tian ◽  
Bo Tang ◽  
Chengye Wang ◽  
Yan Wang ◽  
Jiakai Mao ◽  
...  
Keyword(s):  
Tumour Growth ◽  
Molecular Mechanisms ◽  
Epithelial To Mesenchymal Transition ◽  
Sirtuin 1 ◽  
Mesenchymal Transition ◽  
Specific Protease ◽  
Ubiquitin Specific Protease ◽  
Paired Tumour

AbstractOncogenic ubiquitin-specific protease 22 (USP22) is implicated in a variety of tumours; however, evidence of its role and underlying molecular mechanisms in cholangiocarcinoma (CCA) development remains unknown. We collected paired tumour and adjacent non-tumour tissues from 57 intrahepatic CCA (iCCA) patients and evaluated levels of the USP22 gene and protein by qPCR and immunohistochemistry. Both the mRNA and protein were significantly upregulated, correlated with the malignant invasion and worse OS of iCCA. In cell cultures, USP22 overexpression increased CCA cell proliferation and mobility, and induced epithelial-to-mesenchymal transition (EMT). Upon an interaction, USP22 deubiquitinated and stabilized sirtuin-1 (SIRT1), in conjunction with Akt/ERK activation. In implantation xenografts, USP22 overexpression stimulated tumour growth and metastasis to the lungs of mice. Conversely, the knockdown by USP22 shRNA attenuated the tumour growth and invasiveness in vitro and in vivo. Furthermore, SIRT1 overexpression reversed the USP22 functional deficiency, while the knockdown acetylated TGF-β-activated kinase 1 (TAK1) and Akt. Our present study defines USP22 as a poor prognostic predictor in iCCA that cooperates with SIRT1 and facilitates tumour development.

scholarly journals Molecular mechanisms underpinning sarcomas and implications for current and future therapy

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Victoria Damerell ◽  
Michael S. Pepper ◽  
Sharon Prince
Keyword(s):  
Molecular Mechanisms ◽  
Epithelial To Mesenchymal Transition ◽  
Treatment Strategies ◽  
Mesenchymal Transition ◽  
Mesenchymal To Epithelial Transition ◽  
Cells Of Origin ◽  
Novel Treatment Strategies ◽  
Future Therapy

AbstractSarcomas are complex mesenchymal neoplasms with a poor prognosis. Their clinical management is highly challenging due to their heterogeneity and insensitivity to current treatments. Although there have been advances in understanding specific genomic alterations and genetic mutations driving sarcomagenesis, the underlying molecular mechanisms, which are likely to be unique for each sarcoma subtype, are not fully understood. This is in part due to a lack of consensus on the cells of origin, but there is now mounting evidence that they originate from mesenchymal stromal/stem cells (MSCs). To identify novel treatment strategies for sarcomas, research in recent years has adopted a mechanism-based search for molecular markers for targeted therapy which has included recapitulating sarcomagenesis using in vitro and in vivo MSC models. This review provides a comprehensive up to date overview of the molecular mechanisms that underpin sarcomagenesis, the contribution of MSCs to modelling sarcomagenesis in vivo, as well as novel topics such as the role of epithelial-to-mesenchymal-transition (EMT)/mesenchymal-to-epithelial-transition (MET) plasticity, exosomes, and microRNAs in sarcomagenesis. It also reviews current therapeutic options including ongoing pre-clinical and clinical studies for targeted sarcoma therapy and discusses new therapeutic avenues such as targeting recently identified molecular pathways and key transcription factors.

scholarly journals Potential Role of microRNA-183 as a Tumor Suppressor in Hepatocellular Carcinoma

2018 ◽  
Vol 51 (5) ◽  
pp. 2065-2072 ◽  
Author(s):  
Wei Bian ◽  
Hongfei Zhang ◽  
Miao Tang ◽  
Shaojun Zhang ◽  
Lichao Wang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepg2 Cells ◽  
Molecular Mechanisms ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Metastatic Progression ◽  
Mesenchymal Transition ◽  
Reporter Assays

Background/Aims: Disseminated tumors, known as metastases, are responsible for ninety-percent of mortality due to cancer. Epithelial to mesenchymal transition, a phenomenon required for morphological conversion of non-motile discoid shaped epithelial cells to highly motile spindle-shaped mesenchymal cells, is thought to be a pre-requisite for metastatic progression. Metastasis-associated 1 (MTA1) protein is a prime inducer of EMT and metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the molecular mechanisms that regulate the expression and function of MTA1 in HCC have not been elucidated. Methods: In silico prediction algorithms were used to find microRNAs (miRNAs) that may target MTA1. We examined the relationship between the expression of MTA1 and miR-183 using quantitative real time PCR. We also determined the levels of the MTA1 protein using immunohistochemistry. Reporter assays, in the presence and absence of the miR-183 mimic, were used to confirm MTA1 as a bona fide target of miR183. The effect of miR-183 on HCC pathogenesis was determined using a combination of in vitro migration and invasion assay, together with in vivo xenograft experiments. The correlation between miR-183 and MTA1 expression was also studied in samples from HCC patients, and in The Cancer Genome Atlas dataset. Results: Analysis of the sequence database revealed that MTA1 is a putative target of miR-183. MTA1 protein and RNA expression showed opposite trends to miR-183 expression in breast, renal, prostate, and testicular tissue samples from cancer patients, and in the metastatic HCC cell line HepG2. An inverse correlation was also observed between MTA1 (high) and miR-183 (low) expression within samples from HHC patients and in the TCGA dataset. Reporter assays in HepG2 cells showed that miR-183 could inhibit translation of a reporter harboring the wild-type, but not the mutant miR-183 3’-untranslated region (UTR). In addition, miR-183 significantly inhibited in vitro migration and invasion in HepG2 cells, and in vivo hepatic metastasis. Conclusion: Our results reveal a novel post-transcriptional regulatory mechanism for MTA1 expression via miR-183, which is suppressed during HCC pathogenesis.

scholarly journals Growth hormone protects against radiotherapy-induced cell death

2002 ◽  
pp. 535-541 ◽  
Author(s):  
O Madrid ◽  
S Varea ◽  
I Sanchez-Perez ◽  
L Gomez-Garcia ◽  
E De Miguel ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Cell Death ◽  
Hormone Receptor ◽  
Growth Hormone Receptor ◽  
Molecular Mechanisms ◽  
Dna Double Strand Breaks ◽  
Cell Viability Assay ◽  
Viability Assay ◽  
Rat Growth

BACKGROUND: In vivo treatment with growth hormone reduces radiation-associated mortality. The molecular mechanisms underlying this effect are unknown. It has been described that increased sensitivity to ionising radiation can be due to defects in machinery involved in detection and/or repair of DNA double-strand breaks. OBJECTIVE: To study the mechanisms involved in growth hormone action on the increased survival in irradiated cells. MATERIALS AND METHODS: CHO-4 cells stably expressing the growth hormone receptor were used. A cell viability assay was carried out to analyse the increase in survival induced by growth hormone in irradiated cells. To investigate whether the DNA repair mechanism could be implicated in this effect we performed DNA reactivation assays using pHIV-LUC and pCMV-betagal plasmids as control. Identical studies were also conducted using the radiomimetic drug, bleomycin. RESULTS: Growth hormone protects CHO-4 cells from bleomycin- and radiation-induced cell death. In pHIV-LUC transfected cells, a time-dependent decrease in luciferase activity was observed after irradiation in the absence of growth hormone. However, cells pretreated with this hormone maintained reporter activity. When cells were transfected with irradiated pHIV-LUC plasmid, only the hormone-treated cells recovered the transcriptional activity. CONCLUSIONS: Growth hormone exerts a radioprotective effect in CHO-4 cells stably transfected with the complementary DNA for the rat growth hormone receptor. The radioprotection is triggered directly by the hormone and it is also observed with bleomycin. The increased survival in response to radiation and bleomycin treatment induced by growth hormone correlates with an enhanced ability of the cells to repair damaged DNA.

scholarly journals Linc00426 accelerates lung adenocarcinoma progression by regulating miR-455-5p as a molecular sponge

2020 ◽  
Vol 11 (12) ◽  
Author(s):  
Hongli Li ◽  
Qingjie Mu ◽  
Guoxin Zhang ◽  
Zhixin Shen ◽  
Yuanyuan Zhang ◽  
...  
Keyword(s):  
Lung Adenocarcinoma ◽  
Molecular Mechanisms ◽  
Epithelial Mesenchymal Transition ◽  
Ectopic Expression ◽  
Tumor Development ◽  
Biological Significance ◽  
Mesenchymal Transition

AbstractIncreasing lines of evidence indicate the role of long non-coding RNAs (LncRNAs) in gene regulation and tumor development. Hence, it is important to elucidate the mechanisms of LncRNAs underlying the proliferation, metastasis, and invasion of lung adenocarcinoma (LUAD). We employed microarrays to screen LncRNAs in LUAD tissues with and without lymph node metastasis and revealed their effects on LUAD. Among them, Linc00426 was selected for further exploration in its expression, the biological significance, and the underlying molecular mechanisms. Linc00426 exhibits ectopic expression in LUAD tissues and cells. The ectopic expression has been clinically linked to tumor size, lymphatic metastasis, and tumor differentiation of patients with LUAD. The deregulation of Linc00426 contributes to a notable impairment in proliferation, invasion, metastasis, and epithelial–mesenchymal transition (EMT) in vitro and in vivo. Mechanistically, the deregulation of Linc00426 could reduce cytoskeleton rearrangement and matrix metalloproteinase expression. Meanwhile, decreasing the level of Linc00426 or increasing miR-455-5p could down-regulate the level of UBE2V1. Thus, Linc00426 may act as a competing endogenous RNA (ceRNA) to abate miR-455-5p-dependent UBE2V1 reduction. We conclude that Linc00426 accelerates LUAD progression by acting as a molecular sponge to regulate miR-455-5p, and may be a potential novel tumor marker for LUAD.

AMPK activation by GSK621 inhibits human melanoma cells in vitro and in vivo

2016 ◽  
Vol 480 (4) ◽  
pp. 515-521 ◽  
Author(s):  
Lezi Chen ◽  
Quan Chen ◽  
Guosan Deng ◽  
Shifeng Kuang ◽  
Jihong Lian ◽  
...  
Keyword(s):  
Melanoma Cells ◽  
Human Melanoma ◽  
Ampk Activation ◽  
Human Melanoma Cells

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.

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