scholarly journals A GYS2/p53 negative feedback loop restricts tumor growth in HBV-related hepatocellular carcinoma

2018 ◽  
Author(s):  
Shi-Lu Chen ◽  
Chris Zhiyi Zhang ◽  
Li-Li Liu ◽  
Shi-Xun Lu ◽  
Ying-Hua Pan ◽  
...  

AbstractHepatocarcinogenesis is attributed to the reprogramming of cellular metabolism as consequence of the alteration in metabolite-related gene regulation. Identifying the mechanism of aberrant metabolism is of great potential to provide novel targets for the treatment of hepatocellular carcinoma (HCC). Here, we demonstrated that glycogen synthase 2 (GYS2) restricted tumor growth in HBV-related HCC via a negative feedback loop with p53. Expression of GYS2 was significantly downregulated in HCC and correlated with decreased glycogen content and unfavorable patient outcomes. GYS2 overexpression suppressed, whereas GYS2 knockdown facilitated cell proliferation in vitro and tumor growth in vivo via modulating p53 expression. GYS2 competitively bound to MDM2 to prevent p53 from MDM2-mediated ubiquitination and degradation. Furthermore, GYS2 enhanced the p300-induced acetylation of p53 at K373/382, which in turn inhibited the transcription of GYS2 in the support of HBx/HDAC1 complex. In summary, our findings suggest that GYS2 serves as a prognostic factor and functions as a tumor suppressor in HCC. The newly identified HBx/GYS2/p53 axis is responsible for the deregulation of glycogen metabolism and represents a promising therapeutic target for the clinical management of HCC.SynopsisThis study elucidate the role of GYS2 in glycogen metabolism and the progression of HCC. The newly identified HBx/GYS2/p53 axis is responsible for the deregulation of glycogen metabolism and represents a promising therapeutic target for the clinical management of HCC.Decrease of GYS2 was significantly correlated with decreased glycogen content and unfavorable patient outcomes in a large cohort containing 768 patients with HCC.GYS2 overexpression suppressed, whereas GYS2 knockdown facilitated cell proliferation in vitro and tumor growth in vivo via modulating p53 signaling pathway.GYS2 competitively bound to MDM2 to prevent p53 from MDM2-mediated ubiquitination and degradation.GYS2 enhanced the p300-induced acetylation of p53 at Lys373/382, which in turn inhibited the transcription of GYS2 in the support of HBx/HDAC1 complex.

Cancers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 6197
Author(s):  
Nihad Boukrout ◽  
Mouloud Souidi ◽  
Fatima Lahdaoui ◽  
Belinda Duchêne ◽  
Bernadette Neve ◽  
...  

Background: Pancreatic adenocarcinoma (PDAC) is a deadly cancer with an extremely poor prognosis. MUC4 membrane-bound mucin is neoexpressed in early pancreatic neoplastic lesions and is associated with PDAC progression and chemoresistance. In cancers, microRNAs (miRNAs, small noncoding RNAs) are crucial regulators of carcinogenesis, chemotherapy response and even metastatic processes. In this study, we aimed at identifying and characterizing miRNAs activated downstream of MUC4-associated signaling in pancreatic adenocarcinoma. MiRnome analysis comparing MUC4-KD versus Mock cancer cells showed that MUC4 inhibition impaired miR-210-3p expression. Therefore, we aimed to better understand the miR-210-3p biological roles. Methods: miR-210-3p expression level was analyzed by RT-qPCR in PDAC-derived cell lines (PANC89 Mock and MUC4-KD, PANC-1 and MiaPACA-2), as well as in mice and patients tissues. The MUC4-miR-210-3p regulation was investigated using luciferase reporter construct and chromatin immunoprecipitation experiments. Stable cell lines expressing miR-210-3p or anti-miR-210-3p were established using CRISPR/Cas9 technology or lentiviral transduction. We evaluated the biological activity of miR-210-3p in vitro by measuring cell proliferation and migration and in vivo using a model of subcutaneous xenograft. Results: miR-210-3p expression is correlated with MUC4 expression in PDAC-derived cells and human samples, and in pancreatic PanIN lesions of Pdx1-Cre; LstopL-KrasG12D mice. MUC4 enhances miR-210-3p expression levels via alteration of the NF-κB signaling pathway. Chromatin immunoprecipitation experiments showed p50 NF-κB subunit binding on miR-210-3p promoter regions. We established a reciprocal regulation since miR-210-3p repressed MUC4 expression via its 3′-UTR. MiR-210-3p transient transfection of PANC89, PANC-1 and MiaPACA-2 cells led to a decrease in cell proliferation and migration. These biological effects were validated in cells overexpressing or knocked-down for miR-210-3p. Finally, we showed that miR-210-3p inhibits pancreatic tumor growth and proliferation in vivo. Conclusion: We identified a MUC4-miR-210-3p negative feedback loop in early-onset PDAC, but also revealed new functions of miR-210-3p in both in vitro and in vivo proliferation and migration of pancreatic cancer cells, suggesting a complex balance between MUC4 pro-oncogenic roles and miR-210-3p anti-tumoral effects.


2021 ◽  
Vol 12 (3) ◽  
Author(s):  
Qinkai Zhang ◽  
Xunzhu Zhou ◽  
Maoping Wan ◽  
Xixi Zeng ◽  
Jiarong Luo ◽  
...  

AbstractOvarian cancer (OC) causes more deaths than any other gynecological cancer. Many cellular pathways have been elucidated to be associated with OC development and progression. Specifically, the insulin-like growth factor 1 receptor/insulin receptor substrate 1 (IGF1R/IRS1) pathway participates in OC development. Moreover, accumulating evidence has shown that microRNA deregulation contributes to tumor initiation and progression. Here, our study aimed to investigate the molecular functions and regulatory mechanisms of miR-150, specifically, in OC. We found that the expression of miR-150-5p/3p and their precursor, mir-150, was downregulated in OC tissues; lower mir-150 levels were associated with poor OC patient outcomes. Ectopic mir-150 expression inhibited OC cell growth and metastasis in vitro and in vivo. Furthermore, both IRS1 and IGF1R were confirmed as direct targets of miR-150-5p/3p, and the miR-150-IGF1R/IRS1 axis exerted antitumor effects via the PI3K/AKT/mTOR pathway. Forkhead box protein 3 (FoxP3) positively regulated the expression of miR-150-5p/3p by binding to the mir-150 promoter. In turn, the PI3K/AKT/mTOR pathway downregulated FoxP3 and miR-150-5p/3p. Taken together, these findings indicate that a complex FoxP3-miR-150-IGF1R/IRS1-PI3K/AKT/mTOR feedback loop regulates OC pathogenesis, providing a novel mechanism for miR-150 as a tumor suppressor miRNA in OC.


Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 3054
Author(s):  
Kyra E. de Goede ◽  
Sanne G. S. Verberk ◽  
Jeroen Baardman ◽  
Karl J. Harber ◽  
Yvette van Kooyk ◽  
...  

Cancer cells rely on ATP-citrate lyase (Acly)-derived acetyl-CoA for lipid biogenesis and proliferation, marking Acly as a promising therapeutic target. However, inhibitors may have side effects on tumor-associated macrophages (TAMs). TAMs are innate immune cells abundant in the tumor microenvironment (TME) and play central roles in tumorigenesis, progression and therapy response. Since macrophage Acly deletion was previously shown to elicit macrophages with increased pro- and decreased anti-inflammatory responses in vitro, we hypothesized that Acly targeting may elicit anti-tumor responses in macrophages, whilst inhibiting cancer cell proliferation. Here, we used a myeloid-specific knockout model to validate that absence of Acly decreases IL-4-induced macrophage activation. Using two distinct tumor models, we demonstrate that Acly deletion slightly alters tumor immune composition and TAM phenotype in a tumor type-dependent manner without affecting tumor growth. Together, our results indicate that targeting Acly in macrophages does not have detrimental effects on myeloid cells.


2021 ◽  
Author(s):  
Changzhong Li ◽  
Ruobing Leng ◽  
Yunfang Meng ◽  
Na Li ◽  
Feifei Li ◽  
...  

Abstract The RAC1 signal pathway is involved in various tumor cell biological processes. Here, the role of RAC1-miR-3613-RAC1 negative feedback loop in ovarian cancer was explored. Results showed that RAC1 knockdown up-regulated miR-3613, which in turn inhibited RAC1 expression. RAC1 counteracted the inhibitory effect of miR-3613 on the proliferation and invasion of ovarian cancer cells in vitro and on the tumor growth in vivo. In ovarian cancer, miR-3613 expression was negatively correlated with RAC1, and patients with low miR-3613 expression had poor prognosis. These findings indicate the role of RAC1-miR-3613-RAC1 negative feedback loop in the malignant progression of ovarian cancer and its possible therapeutic values.


2021 ◽  
Vol 12 (3) ◽  
Author(s):  
Yan Liu ◽  
Dong He ◽  
Mengqing Xiao ◽  
Yuxing Zhu ◽  
Jianda Zhou ◽  
...  

AbstractThe long noncoding RNA, LINC00518, is highly expressed in various types of cancers and is involved in cancer progression. Although LINC00518 promotes the metastasis of cutaneous malignant melanoma (CMM), the mechanism underlaying its effects on CMM radiosensitivity remains unclear. In this study, LINC00518 expression was significantly upregulated in CMM samples, and LINC00518 levels were associated with poor prognosis of patients with CMM. Knockdown of LINC00518 in CMM cells significantly inhibited cell invasion, migration, proliferation, and clonogenicity. LINC00518-mediated invasion, migration, proliferation, and clonogenicity were negatively regulated by the microRNA, miR-33a-3p, in vitro, which increased sensitivity to radiotherapy via inhibition of the hypoxia-inducible factor 1α (HIF-1α)/lactate dehydrogenase A glycolysis axis. Additionally, HIF-1α recognized the miR-33a-3p promoter region and recruited histone deacetylase 2, which decreased the expression of miR-33a-3p and formed an LINC00518/miR-33a-3p/HIF-1α negative feedback loop. Furthermore, signaling with initially activated glycolysis and radioresistance in CMM cells was impaired by Santacruzamate A, a histone deacetylase inhibitor, and 2-deoxy-D-glucose, a glycolytic inhibitor. Lastly, knockdown of LINC00518 expression sensitized CMM cancer cells to radiotherapy in an in vivo subcutaneously implanted tumor model. In conclusion, LINC00518 was confirmed to be an oncogene in CMM, which induces radioresistance by regulating glycolysis through an miR-33a-3p/HIF-1α negative feedback loop. Our study, may provide a potential strategy to improve the treatment outcome of radiotherapy in CMM.


2006 ◽  
Vol 27 (2) ◽  
pp. 518-525 ◽  
Author(s):  
Michael Haberland ◽  
Michael A. Arnold ◽  
John McAnally ◽  
Dillon Phan ◽  
Yuri Kim ◽  
...  

ABSTRACT Skeletal muscle development is controlled by the myocyte enhancer factor (MEF2) and myogenic basic helix-loop-helix (bHLH) families of transcription factors, which associate and synergistically activate muscle gene expression. Muscle differentiation is further reinforced by positive-feedback loops in which myogenic bHLH proteins activate their own expression and the expression of MEF2, while MEF2 stimulates expression of myogenic bHLH genes and the Mef2c gene. Here we describe a myogenic negative-feedback loop that consists of MEF2 proteins and the transcriptional repressor histone deacetylase 9 (HDAC9). We show that the HDAC9 gene is a direct transcriptional target of MEF2 in vitro and in vivo. HDAC9 can associate with MEF2 proteins and suppress their transcriptional activity. The transcriptional repressor HDAC9 thus forms a negative-feedback loop in the transcriptional circuitry of muscle differentiation.


2020 ◽  
Author(s):  
Ke Cao ◽  
Liu yan ◽  
He Dong ◽  
Xiao Mengqin ◽  
Xiang Liang ◽  
...  

Abstract Background: The long non-coding RNA (lncRNA),LINC00518, is highly expressed in many human cancers and is involved in cancer progression. However, the potential function and regulatory mechanism of LINC00518 in cutaneous malignant melanoma (CMM) remain unclear. Methods:Short hairpin RNA (shRNA) was used to silence LINC00518 and HIF-1α, and real-time PCR was performed to determine mRNA expression. Then, cell proliferation, colony formation, flow cytometric, scratch, and transwell assays were to examine the influence of LINC00518 silencing on cellular radiosensitivity. Dual luciferase reporter system,CHIP and COIP was used to verify the target relationship between LINC00518,miR‐33a-5b and HIF-1α,.Glycolysis assays were conducted to exam cell glycolysis process. Western blotting was performed to explore the expression of HIF-1α and LDHA. Finally, animal experiments were performed to demonstrate the effect of LINC00518 silencing on the radiosensitivity of melanoma in vivo.Results: LINC00518 expression was significantly upregulated in CMM samples, and LINC00518 levels were associated with poor prognosis of patients with CMM. Knockdown of LINC00518 in CMM cells significantly inhibited cell invasion, migration, proliferation, and clonogenicity. LINC00518-mediated invasion, migration, proliferation, and clonogenicity were negatively regulated by the microRNA, miR-33a-3p, in vitro, which intensified sensitivity to radiotherapy via inhibition of the hypoxia-induced factor 1α (HIF-1α)/lactate dehydrogenase A (LDHA)-glycolysis axis. Additionally, HIF-1α recognized the miR-33a-3p promoter region and recruited histone deacetylase2 (HDAC2), which decreased the expression of miR-33a-3p and formed an LINC00518/miR-33a-3p/HIF-1α negative feedback loop. Furthermore, signalling initially activated glycolysis and radioresistance in CMM cells was recovered by Santacruzamate A (a histone deacetylase inhibitor) and 2-deoxy-D-glucose (a glycolytic inhibitor). Lastly, knockdown of LINC00518 expression sensitized CMM cancer cells to radiotherapy in an in vivo subcutaneously implanted tumour model. Conclusion: LINC00518 was confirmed to be an oncogene in CMM, which induces radioresistance by regulating glycolysis through an miR-33a-3p/HIF-1α negative feedback loop. Our research may provide a potential strategy to improve the treatment outcome of radiotherapy in CMM.


2019 ◽  
Vol 2 (4) ◽  
pp. 83-98 ◽  
Author(s):  
André De Lima Mota ◽  
Bruna Vitorasso Jardim-Perassi ◽  
Tialfi Bergamin De Castro ◽  
Jucimara Colombo ◽  
Nathália Martins Sonehara ◽  
...  

Breast cancer is the most common cancer among women and has a high mortality rate. Adverse conditions in the tumor microenvironment, such as hypoxia and acidosis, may exert selective pressure on the tumor, selecting subpopulations of tumor cells with advantages for survival in this environment. In this context, therapeutic agents that can modify these conditions, and consequently the intratumoral heterogeneity need to be explored. Melatonin, in addition to its physiological effects, exhibits important anti-tumor actions which may associate with modification of hypoxia and Warburg effect. In this study, we have evaluated the action of melatonin on tumor growth and tumor metabolism by different markers of hypoxia and glucose metabolism (HIF-1α, glucose transporters GLUT1 and GLUT3 and carbonic anhydrases CA-IX and CA-XII) in triple negative breast cancer model. In an in vitro study, gene and protein expressions of these markers were evaluated by quantitative real-time PCR and immunocytochemistry, respectively. The effects of melatonin were also tested in a MDA-MB-231 xenograft animal model. Results showed that melatonin treatment reduced the viability of MDA-MB-231 cells and tumor growth in Balb/c nude mice (p <0.05). The treatment significantly decreased HIF-1α gene and protein expression concomitantly with the expression of GLUT1, GLUT3, CA-IX and CA-XII (p <0.05). These results strongly suggest that melatonin down-regulates HIF-1α expression and regulates glucose metabolism in breast tumor cells, therefore, controlling hypoxia and tumor progression. 


Author(s):  
С.В. Калиш ◽  
С.В. Лямина ◽  
А.А. Раецкая ◽  
И.Ю. Малышев

Цель исследования. Репрограммирование М1 фенотипа макрофагов с ингибированными факторами транскрипции М2 фенотипа STAT3, STAТ6 и SMAD и оценка их влияния на развитие карциномы Эрлиха (КЭ) in vitro и in vivo. Методика. Рост опухоли иницировали in vitro путем добавления клеток КЭ в среду культивирования RPMI-1640 и in vivo путем внутрибрюшинной инъекции клеток КЭ мышам. Результаты. Установлено, что M1макрофаги и in vitro, и in vivo оказывают выраженный противоопухолевый эффект, который превосходит антиопухолевые эффекты М1, M1, M1 макрофагов и цисплатина. Заключение. М1 макрофаги с ингибированными STAT3, STAT6 и/или SMAD3 эффективно ограничивают рост опухоли. Полученные данные обосновывают разработку новой технологии противоопухолевой клеточной терапии. Objective. Reprogramming of M1 macrophage phenotype with inhibited M2 phenotype transcription factors, such as STAT3, STAT6 and SMAD and assess their impact on the development of Ehrlich carcinoma (EC) in vitro and in vivo . Methods. Tumor growth in vitro was initiated by addition of EC cells in RPMI-1640 culture medium and in vivo by intraperitoneal of EC cell injection into mice. Results. It was found that M1 macrophages have a pronounced anti-tumor effect in vitro , and in vivo , which was greater than anti-tumor effects of M1, M1, M1 macrophages and cisplatin. Conclusion. M1 macrophages with inhibited STAT3, STAT6 and/or SMAD3 effectively restrict tumor growth. The findings justify the development of new anti-tumor cell therapy technology.


2012 ◽  
Vol 38 (12) ◽  
pp. 1121-1131
Author(s):  
Xiao-Hui WANG ◽  
Ya-Min ZHENG ◽  
Ye-Qing CUI ◽  
Shuang LIU ◽  
Hai-Chen SUN ◽  
...  

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