Browse
Submit Data
Databases
API
Help

Dataset Information

18 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

NEAT1 Confers Radioresistance to Hepatocellular Carcinoma Cells by Inducing Autophagy through GABARAP.

ABSTRACT: A long noncoding RNA (lncRNA), nuclear enriched abundant transcript 1 (NEAT1) variant 1 (NEAT1v1), is involved in the maintenance of cancer stem cells (CSCs) in hepatocellular carcinoma (HCC). CSCs are suggested to play important roles in therapeutic resistance. Therefore, we investigated whether NEAT1v1 is involved in the sensitivity to radiation therapy in HCC. Gene knockdown was performed using short hairpin RNAs, and NEAT1v1-overexpressing HCC cell lines were generated by stable transfection with a NEAT1v1-expressing plasmid DNA. Cells were irradiated using an X-ray generator. We found that NEAT1 knockdown enhanced the radiosensitivity of HCC cell lines and concomitantly inhibited autophagy. NEAT1v1 overexpression enhanced autophagy in the irradiated cells and conferred radioresistance. Gamma-aminobutyric acid receptor-associated protein (GABARAP) expression was downregulated by NEAT1 knockdown, whereas it was upregulated in NEAT1v1-overexpressing cells. Moreover, GABARAP was required for NEAT1v1-induced autophagy and radioresistance as its knockdown significantly inhibited autophagy and sensitized the cells to radiation. Since GABARAP is a crucial protein for the autophagosome-lysosome fusion, our results suggest that NEAT1v1 confers radioresistance to HCC by promoting autophagy through GABARAP.

SUBMITTER: Sakaguchi H

PROVIDER: S-EPMC8775719 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Egr-1 regulates irradiation-induced autophagy through Atg4B to promote radioresistance in hepatocellular carcinoma cells.

Project description:Although hepatocellular carcinoma (HCC) is usually response to radiation therapy, radioresistance is still the major obstacle that limits the efficacy of radiotherapy for HCC patients. Therefore, further investigation of underlying mechanisms in radioresistant HCC cells is warranted. In this study, we determined the effect of early growth response factor (Egr-1) on irradiation-induced autophagy and radioresistance in HCC cell lines SMMC-7721 and HepG2. We showed that autophagy-related gene 4B (Atg4B) is induced by Egr-1 upon ionizing radiation (IR) in HCC cells. Luciferase reporter assays and chromatin immunoprecipitation (ChIP) revealed that Egr-1 binds to the Atg4B promoter to upregulate its expression in HCC cells. Suppression of Egr-1 function by dominant-negative Egr-1 dampens IR-induced autophagy, cell migration, and increases cell sensitivity to radiotherapy. Together, these results suggest that Egr-1 contributes to HCC radioresistance through directly upregulating target gene Atg4B, which may serve as a protective mechanism by preferential activation of the autophagy.

| S-EPMC5294254 | biostudies-literature

EBV-LMP1 promotes radioresistance by inducing protective autophagy through BNIP3 in nasopharyngeal carcinoma.

Project description:Studies have indicated that dysfunction of autophagy is involved in the initiation and progression of multiple tumors and their chemoradiotherapy. Epstein-Barr virus (EBV) is a lymphotropic human gamma herpes virus that has been implicated in the pathogenesis of nasopharyngeal carcinoma (NPC). EBV encoded latent membrane protein1 (LMP1) exhibits the properties of a classical oncoprotein. In previous studies, we experimentally demonstrated that LMP1 could increase the radioresistance of NPC. However, how LMP1 contributes to the radioresistance in NPC is still not clear. In the present study, we found that LMP1 could enhance autophagy by upregulating the expression of BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3). Knockdown of BNIP3 could increase the apoptosis and decrease the radioresistance mediated by protective autophagy in LMP1-positive NPC cells. The data showed that increased BNIP3 expression is mediated by LMP1 through the ERK/HIF1α signaling axis, and LMP1 promotes the binding of BNIP3 to Beclin1 and competitively reduces the binding of Bcl-2 to Beclin1, thus upregulating autophagy. Furthermore, knockdown of BNIP3 can reduce the radioresistance promoted by protective autophagy in vivo. These data clearly indicated that, through BNIP3, LMP1 induced autophagy, which has a crucial role in the protection of LMP1-positive NPC cells against irradiation. It provides a new basis and potential target for elucidating LMP1-mediated radioresistance.

| S-EPMC8016912 | biostudies-literature

Peptidylarginine deiminase IV promotes the development of chemoresistance through inducing autophagy in hepatocellular carcinoma.

Project description:BackgroundPeptidylarginine deiminase IV (PADI4) is widely distributed in several tissues and the expression is correlated with many pathological processes. Chemotherapy remains a major treatment alternatively to surgery for a large number of patients at the advanced stage of hepatocellular carcinoma (HCC). However, the role of PADI4 in the chemoresistance of HCC has not been identified.MethodsMTT and PI/Annexin V assay were employed to examine the proliferation and apoptosis of HCC cell lines. The expression of MDR1 is detected by Realtime PCR. GFP tagged LC3 expression vector and electron microscopy are utilized to demonstrate the occurrence of autophagy.ResultsWe observed that the elevated PADI4 expression is associated with chemoresistance in HCC patients with TACE after surgery. In addition, we found that overexpression of PADI4 in HCC cell lines lead to the resistance to chemotherapeutic agents in vitro and in vivo. Interestingly, the HCC cells that overexpressed PADI4 were observed to undergo autophagy which was known as a protective mechanism for cells to resist the cell tosicity from chemotherapy. Autophagy inhibitor could effectively restore the sensitivity of HCC cells to chemotherapy in vitro and in vivo.ConclusionsThese results indicate that PADI4 may induce chemoresistance in HCC cells by leading autophagy.

| S-EPMC4412294 | biostudies-literature

PBK, targeted by EVI1, promotes metastasis and confers cisplatin resistance through inducing autophagy in high-grade serous ovarian carcinoma.

Project description:High-grade serous ovarian carcinoma (HGSOC) is the most lethal type of gynecologic malignancy. Chemoresistance is the main reason for the poor prognosis of HGSOC. PDZ-binding kinase (PBK) promotes the malignant progression of various carcinomas. However, the roles and clinical significance of PBK in HGSOC remain unclear. Here, we reported that PBK was overexpressed in HGSOC tissues and cell lines. High PBK expression was associated with a poor prognosis, metastasis, and cisplatin resistance of HGSOC. Overexpression of PBK promoted autophagy and enhanced cisplatin resistance via the ERK/mTOR signaling pathway. Further study showed that inhibition of autophagy by chloroquine or bafilomycin A1 reversed PBK-induced cisplatin resistance. Overexpression of PBK decreased ovarian cancer responsiveness to cisplatin treatment through inducing autophagy in vivo. We also demonstrated that the PBK inhibitor OTS514 augmented the growth inhibition effect of cisplatin in vitro and in vivo. Moreover, ecotropic viral integration site-1 (EVI1) could regulate PBK expression through directly targeting the PBK promoter region. In conclusion, high PBK expression was correlated with a poor prognosis, metastasis, and cisplatin resistance through promoting autophagy in HGSOC. PBK might be a promising target for the early diagnosis and individual treatment of ovarian cancer.

| S-EPMC6379381 | biostudies-literature

Deubiquitinase USP9x confers radioresistance through stabilization of Mcl-1.

Project description:Myeloid cell leukemia sequence 1 (Mcl-1), an antiapoptotic member of the Bcl-2 family, is often overexpressed in tumor cells limiting the therapeutic success. Mcl-1 differs from other Bcl-2 members by its high turnover rate. Its expression level is tightly regulated by ubiquitylating and deubiquitylating enzymes. Interaction of Mcl-1 with certain Bcl-2 homology domain 3 (BH3)-only members of the Bcl-2 family can limit the access to Mcl-1 ubiquitin ligase E3 and stabilizes the antiapoptotic protein. In addition, the overexpression of the deubiquitinase ubiquitin-specific protease 9x (USP9x) can result in the accumulation of Mcl-1 by removing poly-ubiquitin chains from Mcl-1 preventing its proteasomal degradation. Analyzing radiation-induced apoptosis in Jurkat cells, we found that Mcl-1 was downregulated more efficiently in sensitive parental cells than in a resistant subclone. The decline of Mcl-1 correlated with cell death induction and clonogenic survival. Knockdown of BH3-only proteins Bim, Puma, and Noxa did not affect Mcl-1 level or radiation-induced apoptosis. However, ionizing radiation resulted in activation of USP9x and enhanced deubiquitination of Mcl-1 in the radioresistant cells preventing fast Mcl-1 degradation. USP9x knockdown enhanced radiation-induced decrease of Mcl-1 and sensitized the radioresistant cells to apoptosis induction, whereas USP9x knockdown alone did not change Mcl-1 level in unirradiated cells. Together, our results indicate that radiation-induced activation of USP9x inhibits Mcl-1 degradation and apoptosis resulting in increased radioresistance.

| S-EPMC3479835 | biostudies-other

N6-methyladenosine modification of circCUX1 confers radioresistance of hypopharyngeal squamous cell carcinoma through caspase1 pathway.

Project description:Hypopharyngeal squamous cell carcinoma (HPSCC) is one of the most common malignant tumors in otolaryngology head and neck surgery and is one of the worst prognostic malignant tumors. Endogenous circular RNA (circRNA) is more stable than mRNA, microRNA (miRNA), and long non-coding RNA (LncRNA) in exosomes, plasma, and urine, and participates in gene expression regulation to perform different functions. Therefore, circRNA is expected to become a biomarker and therapy target for many tumors. However, the expression and function of circRNA regulated by N6-methyladenosine (m6A) are still unclear in HNSCC. In this study, we demonstrated that a specific circRNA, circCUX1, was upregulated in HPSCC patients who are resistant to radiotherapy and predicts poor survival outcome. We further found that methyltransferase like 3 (METTL3) mediated the m6A methylation of circCUX1 and stabilizes its expression. Knockdown circCUX1 promotes the sensitivity of hypopharyngeal cancer cells to radiotherapy. In addition, circCUX1 binds to Caspase1 and inhibits its expression, resulting in a decrease in the release of inflammatory factors, thereby developing tolerance to radiotherapy. Our findings indicate that circCUX1 is a potential therapeutic target for radiotherapy tolerance in HPSCC patients.

| S-EPMC7979824 | biostudies-literature

Ginsenoside Rh2 inhibits hepatocellular carcinoma through β-catenin and autophagy.

Project description:Hepatocellular carcinoma (HCC) is the most common liver cancer, with a very poor prognosis. There is an urgent need for an effective therapy for HCC. Ginsenoside Rh2 (GRh2) has been shown to significantly inhibit growth of some types of cancer, whereas its effects on HCC have not been examined. Here, we treated human HCC cells with different doses of GRh2, and found that GRh2 dose-dependently reduced HCC viability, in either CCK-8 assay or MTT assay. The effects of GRh2 on the cancer stem cells (CSCs)-like cells were determined by aldefluor flow cytometry and by tumor sphere formation, showing that GRh2 dose-dependently decreased the number of these CSCs-like cells in HCC. Autophagy-associated protein and β-catenin level were measured in GRh2-treated HCC cells by Western blot, showing that GRh2 increased autophagy and inhibited β-catenin signaling. Expression of short hairpin small interfering RNA (shRNA) for Atg7 in HCC cells completely abolished the effects of GRh2 on β-catenin and cell viability, while overexpression of β-catenin abolished the effects of GRh2 on autophagy and cell viability. Together, our data suggest that GRh2 may inhibit HCC cell growth, possibly through a coordinated autophagy and β-catenin signaling.

| S-EPMC4725994 | biostudies-other

MAPK14/p38? confers irinotecan resistance to TP53-defective cells by inducing survival autophagy.

Project description:Recently we have shown that the mitogen-activated protein kinase (MAPK) MAPK14/p38? is involved in resistance of colon cancer cells to camptothecin-related drugs. Here we further investigated the cellular mechanisms involved in such drug resistance and showed that, in HCT116 human colorectal adenocarcinoma cells in which TP53 was genetically ablated (HCT116-TP53KO), overexpression of constitutively active MAPK14/p38? decreases cell sensitivity to SN-38 (the active metabolite of irinotecan), inhibits cell proliferation and induces survival-autophagy. Since autophagy is known to facilitate cancer cell resistance to chemotherapy and radiation treatment, we then investigated the relationship between MAPK14/p38?, autophagy and resistance to irinotecan. We demonstrated that induction of autophagy by SN38 is dependent on MAPK14/p38? activation. Finally, we showed that inhibition of MAPK14/p38? or autophagy both sensitizes HCT116-TP53KO cells to drug therapy. Our data proved that the two effects are interrelated, since the role of autophagy in drug resistance required the MAPK14/p38?. Our results highlight the existence of a new mechanism of resistance to camptothecin-related drugs: upon SN38 induction, MAPK14/p38? is activated and triggers survival-promoting autophagy to protect tumor cells against the cytotoxic effects of the drug. Colon cancer cells could thus be sensitized to drug therapy by inhibiting either MAPK14/p38 or autophagy.

| S-EPMC3429546 | biostudies-literature

Centriolar Satellites Control GABARAP Ubiquitination and GABARAP-Mediated Autophagy.

Project description:Autophagy maintains cellular health and homeostasis during stress by delivering cytosolic material captured by autophagosomes to lysosomes for degradation. Autophagosome formation is complex: initiated by the recruitment of autophagy (Atg) proteins to the formation site, it is sustained by activation of Atg proteins to allow growth and closure of the autophagosome. How Atg proteins are translocated to the forming autophagosome is not fully understood. Transport of the ATG8 family member GABARAP from the centrosome occurs during starvation-induced autophagosome biogenesis, but how centrosomal proteins regulate GABARAP localization is unknown. We show that the centriolar satellite protein PCM1 regulates the recruitment of GABARAP to the pericentriolar material. In addition to residing on the pericentriolar material, GABARAP marks a subtype of PCM1-positive centriolar satellites. GABARAP, but not another ATG8 family member LC3B, binds directly to PCM1 through a canonical LIR motif. Loss of PCM1 results in destabilization of GABARAP, but not LC3B, through proteasomal degradation. GABARAP instability is mediated through the centriolar satellite E3 ligase Mib1, which interacts with GABARAP through its substrate-binding region and promotes K48-linked ubiquitination of GABARAP. Ubiquitination of GABARAP occurs in the N terminus, a domain associated with ATG8-family-specific functions during autophagosome formation, on residues absent in the LC3 family. Furthermore, PCM1-GABARAP-positive centriolar satellites colocalize with forming autophagosomes. PCM1 enhances GABARAP/WIPI2/p62-positive autophagosome formation and flux but has no significant effect on LC3B-positive autophagosome formation. These data suggest a mechanism for how centriolar satellites can specifically regulate an ATG8 ortholog, the centrosomal GABARAP reservoir, and centrosome-autophagosome crosstalk.

| S-EPMC5526835 | biostudies-literature

REV7 confers radioresistance of esophagus squamous cell carcinoma by recruiting PRDX2.

Project description:Radiotherapy has been widely used for the clinical management of esophageal squamous cell carcinoma. However, radioresistance remains a serious concern that prevents the efficacy of esophageal squamous cell carcinoma (ESCC) radiotherapy. REV7, the structural subunit of eukaryotic DNA polymerase ζ, has multiple functions in bypassing DNA damage and modulating mitotic arrest in human cell lines. However, the expression and molecular function of REV7 in ESCC progression remains unclear. In this study, we first examined the expression of REV7 in clinical ESCC samples, and we found higher expression of REV7 in ESCC tissues compared to matched adjacent or normal tissues. Knockdown of REV7 resulted in decreased colony formation and increased apoptosis in irradiated Eca-109 and TE-1 cells coupled with decreased tumor weight in a xenograft nude mouse model postirradiation. Conversely, overexpression of REV7 resulted in radioresistance in vitro and in vivo. Moreover, silencing of REV7 induced increased reactive oxygen species levels postirradiation. Proteomic analysis of REV7-interacting proteins revealed that REV7 interacted with peroxiredoxin 2 (PRDX2), a well-known antioxidant protein. Existence of REV7-PRDX2 complex and its augmentation postirradiation were further validated by immunoprecipitation and immunofluorescence assays. REV7 knockdown significantly disrupted the presence of nuclear PRDX2 postirradiation, which resulted in oxidative stress. REV7-PRDX2 complex also assembled onto DNA double-strand breaks, whereas REV7 knockdown evidently increased double-strand breaks that were unmerged by PRDX2. Taken together, the present study sheds light on REV7-modulated radiosensitivity through interacting with PRDX2, which provides a novel target for ESCC radiotherapy.

| S-EPMC6398896 | biostudies-other

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data