Long non-coding RNA GAS5 promotes cisplatin-chemosensitivity of osteosarcoma cells via microRNA-26b-5p/TP53INP1 axis.

Osteosarcoma is a common malignant bone tumor. Cisplatin (DDP) achieves a high response rate in osteosarcoma. Here we aim to study the dysregulation of long non-coding RNA the growth arrest-specific transcript 5 (GAS5), and its roles in DDP-resistance of osteosarcoma. The expression of mRNA and microRNA in osteosarcoma tissues and osteosarcoma cell lines were detected by quantitative reverse-transcription polymerase chain reaction, and protein expression levels were measured by western blotting assay. Cell Counting Kit-8 and 5-Ethynyl-2'-deoxyuridine were used to measure cell proliferation. Flow cytometer assay was used to evaluate cell apoptosis. The interactions between miR-26b-5p and GAS5 or tumor protein p53-induced nuclear protein 1 (TP53INP1) were verified by dual luciferase reporter along with biotin RNA pull-down assays. GAS5 was identified to be significantly lowly expressed in osteosarcoma samples especially in cisplatin-resistant (DDP-resistant) tissues. GAS5 was also downregulated in DDP-resistant cells. Over-expressed GAS5 prominently increased the sensitivity of osteosarcoma cells to DDP in vitro. Furthermore, over-expression of GAS5 suppressed cell proliferation and facilitated apoptosis of DDP-resistant cells. Mechanistically, GAS5 sponged miR-26b-5p, over-expression of which reversed the effects of GAS5 on cell proliferation and apoptosis of DDP-resistant cells. In addition, miR-26b-5p targeted TP53INP1. TP53INP1 abrogated the functions of miR-26b-5p on cell proliferation and apoptosis in DDP-resistant cells. Taken together, GAS5 enhanced the sensitivity of osteosarcoma cells to DDP via GAS5/miR-26b-5p/TP53INP1 axis. Therefore, GAS5 may be a potential indicator for the management of osteosarcoma.

Curcumin Increases Radiosensitivity of Radioresistant Nasopharyngeal Cancer.

OBJECTIVES: To study the effects of curcumin on the proliferation, invasion, apoptosis, and radiosensitivity of the radioresistant nasopharyngeal carcinoma (NPC) C6661-IR strain as well as the potential radiosensitization mechanism. METHODS: NPC cells were continuously irradiated with different intensities of radiation to induce radiation-resistant cell lines. A plate clone formation assay was used to evaluate the effect of curcumin on the radiosensitivity of NPC cells. 3-(4,5-Dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide thiazolyl blue (MTT) assay was conducted to detect changes in cell viability. Flow cytometry was employed to analyze apoptosis percentage as well as Transwell® assay and immunofluorescence assay to observe cell invasion. Western blotting was applied to detect the expression levels of Bax, Bcl-2, and pro/cleaved-caspase 3. MiR-205-5p mimics and si-TP53INP1 were synthesized and transfected into C6661-IR cells, and the cells were then incubated with 10 µm/L curcumin. Real-time quantitative reverse transcription PCR (RT-qPCR) was used to measure miR-205-5p levels and western blotting was conducted to detect the expression of TP53INP1. RESULTS: The optimal radiation dose of X-ray was 6 Gy, and this dose was used in all subsequent experiments. Curcumin treatment significantly inhibited the proliferation and invasion of C6661-IR cells, promoted apoptosis and enhanced radiosensitivity. Compared to the 0 Gy+Cur group and the 6 Gy+Cur group, the miR-205-5p levels were higher in the C6661-IR cells of the 0 Gy and 6 Gy groups. Moreover, miR-204-5p was found to directly target TP53INP1. Curcumin downregulated miR-205-5p levels and upregulated TP53INP1 expression (p < 0.05). Thus, modulation of miR-205-5p or TP53INP1 expression attenuates the biological effects of curcumin on C6661-IR cells. CONCLUSIONS: Curcumin inhibited the proliferation and invasion of C6661-IR, promoted apoptosis, and enhanced its radiosensitivity to X-rays by mediating miR-205-5p/TP53INP1 expression.

Exosomal LINC00355 promotes the malignant progression of gastric cancer through histone deacetylase HDAC3-mediated TP53INP1 transcriptional inhibition.

AIMS: Exosomes are a subpopulation of extracellular vesicles (EV) derived from multivesicular body (MVB) that transmit various cellular molecular constituents, including long noncoding RNAs (lncRNAs), to promote intercellular communication. Our aim was to investigate the function and mechanism of exosomal LINC00355 in gastric cancer cells. MAIN METHODS: Exosomal levels of LINC00355 in GC patients and healthy controls were measured by RT-qPCR. The effects of exosomal LINC00355 on GC cell viability, proliferation, migration and invasion were evaluated by CCK8, colony formation, Transwell and wound healing assays. The expression levels of Ki67 in xenograft tumor tissues were confirmed by immunohistochemistry assay, and apoptosis was analyzed by TUNEL apoptosis assay. Western blotting was used to monitor protein expression. RNA immunoprecipitation and RNA pulldown were performed to detect the interaction between LINC00355 and HDAC3. Chromatin immunoprecipitation was used to assess the interaction of HDAC3 with the TP53INP1 promoter. KEY FINDINGS: Exosomal LINC00355 levels were higher in plasma from gastric cancer patients than in plasma from healthy volunteers. Exosomal LINC00355 promoted the proliferation, migration and invasion of gastric cancer cell lines. RNA sequence analysis demonstrated that LINC00355 knockdown downregulated histone deacetylase HDAC3 and upregulated TP53INP1. Mechanistic investigation indicated that exosomal LINC00355 interacted with HDAC3 to suppress TP53INP1 transcription, which promoted epithelial-mesenchymal transition (EMT). SIGNIFICANCE: Exosomal LINC00355 plays a pivotal role in regulating EMT to induce the malignant progression of GC. Exosomal LINC00355 could be a promising biomarker in the early diagnosis and prognosis of GC.

Dual inhibition of EZH1/2 induces cell cycle arrest of B cell acute lymphoblastic leukemia cells through upregulation of CDKN1C and TP53INP1.

Disease-risk stratification and development of intensified chemotherapy protocols have substantially improved the outcome of acute lymphoblastic leukemia (ALL). However, outcomes of relapsed or refractory cases remain poor. Previous studies have discussed the oncogenic role of enhancer of zeste homolog 1 and 2 (EZH1/2), and the efficacy of dual inhibition of EZH1/2 as a treatment for hematological malignancy. Here, we investigated whether an EZH1/2 dual inhibitor, DS-3201 (valemetostat), has antitumor effects on B cell ALL (B-ALL). DS-3201 inhibited growth of B-ALL cell lines more significantly and strongly than the EZH2-specific inhibitor EPZ-6438, and induced cell cycle arrest and apoptosis in vitro. RNA-seq analysis to determine the effect of DS-3201 on cell cycle arrest-related genes expressed by B-ALL cell lines showed that DS-3201 upregulated CDKN1C and TP53INP1. CRIPSR/Cas9 knockout confirmed that CDKN1C and TP53INP1 are direct targets of EZH1/2 and are responsible for the antitumor effects of DS-3201 against B-ALL. Furthermore, a patient-derived xenograft (PDX) mouse model showed that DS-3201 inhibited the growth of B-ALL harboring MLL-AF4 significantly. Thus, DS-3201 provides another option for treatment of B-ALL.

LncRNA n339260 functions in hepatocellular carcinoma progression via regulation of miRNA30e-5p/TP53INP1 expression.

BACKGROUND: Currently, the molecular mechanism of the interaction between lncRNAs and microRNAs (miRNAs) and the target of miRNAs in tumor vasculogenic mimicry (VM) formation have not been clarified. Our aim is to study the interaction between lncRNA n339260 and miRNA30e-5p in the formation of VM. METHODS: Animal xenografts were established, 104 hepatocellular carcinoma (HCC) patients' frozen tissues were obtained and HCC cells in vitro were used to observe the role of n339260 in HCC progression. RESULTS: In vivo experiment showed lncRNA n339260 promoted tumor growth and VM formation. LncRNA n339260 and miRNA30e-5p were found to be associated with VM formation, metastasis and survival time in HCC patients. In vitro experiment showed that LncRNA n339260 could inhibit miRNA30e-5p expression and TP53INP1 was found to be the downstream targets of miRNA30e-5p. Snail, MMP2, MMP9, VE-cadherin, vimentin and N-cadherin overexpression and the downregulation of TP53INP1 and E-cadherin were observed in HCCLM3 and HepG2 cells overexpressing lncRNA n339260 or in cells with decreased expression of miRNA30e-5p. CONCLUSION: LncRNA n339260 promotes the development of VM, and lncRNA n339260 may enhance Snail expression by decreasing the expression of miRNA30e-5p, thereby reducing TP53INP1 expression. Therefore, a potential lncRNA n339260- miRNA30e-5p- TP53INP1 regulatory axis was associated with HCC progression.

miR-8485 alleviates the injury of cardiomyocytes through TP53INP1.

MicroRNAs (miRNAs) feature prominently in regulating the progression of chronic heart failure (CHF). This study was performed to investigate the role of miR-8485 in the injury of cardiomyocytes and CHF. It was found that miR-8485 level was markedly reduced in the plasma of CHF patients, compared with the healthy controls. H2 O2 treatment increased tumor necrosis factor-α, interleukin (IL)-6, and IL-1ß levels, inhibited the viability of human adult ventricular cardiomyocyte cell line AC16, and increased the apoptosis, while miR-8485 overexpression reversed these effects. Tumor protein p53 inducible nuclear protein 1 (TP53INP1) was identified as a downstream target of miR-8485, and TP53INP1 overexpression weakened the effects of miR-8485 on cell viability, apoptosis, as well as inflammatory responses. Our data suggest that miR-8485 attenuates the injury of cardiomyocytes by targeting TP53INP1, suggesting it is a protective factor against CHF.

Designed miR-19a/b sponge induces apoptosis in lung cancer cells through the PI3K-PTEN-Akt pathway regulation.

BACKGROUND: MicroRNAs (miRNAs) are one of the main factors in cancer development and can alter the activity of proto-oncogenic or tumor suppressor genes. The miR-17-92 cluster, which comprises miR-17, miR-18a, miR-19a/b, miR-20a, and miR-92a, has been identified as a biomarker in a variety of cancer types. Among them, miR-19a/b exerts an oncogenic effect by suppressing tumor suppressor genes, including PTEN and TP53INP1in numerous types of cancers, including NSCLC. An miRNA sponge is an mRNA with multiple repetitive sequences that prevents miRNAs from interacting with their targets, thereby inhibiting their action. METHODS AND RESULTS: In this study, we designed an miR-19a/b sponge plasmid and transfected it into A549 lung cancer cell lines and analyzed its effects on PTEN and TP53INP1 gene expression as the main miR-19a/b target and apoptosis rate in these cell lines. CONCLUSIONS: The findings revealed that miR-19a/b sponge significantly increased PTEN and TP53INP1 mRNA expression. The effect of the sponge on TP53INP1 was much greater than that on PTEN. This is because TP53INP1 is directly (sponge effect) and indirectly (AKT pathway is affected by the P53 gene) affected by this sponge. In addition, compared with the control group, the percentage of primary and secondary apoptosis increased significantly (P value < 0.0001).

MiR-155 inhibits TP53INP1 expression leading to enhanced glycolysis of psoriatic mesenchymal stem cells.

BACKGROUND: Psoriasis is a systemic disease with multiple associated comorbidities, including metabolic syndrome. Studies suggest that chronic inflammation is a central link between psoriasis and metabolic abnormalities. MiR-155 is a well-known microRNA that plays an important regulatory role in inflammation. Studies from our group and others have demonstrated an upregulation of miR-155 in psoriasis. OBJECTIVES: Here, we investigated whether miR-155 regulates glycolysis of psoriasis and the underlying mechanisms. METHODS: Human dermal-derived mesenchymal stem cells (MSC) were treated with miR-155 mimic or inhibitor, followed by assessments of cells proliferation, metabolism and inflammatory response. Target gene prediction and GO/Pathway analysis were used to screen the putative targets involved in the pathways of metabolism, and verified by dual-luciferase reporter assay. To determine whether TP53INP1/p53 signaling pathway is involved in miR-155-mediated regulation of glycolysis, changes in glycolysis were assessed in psoriatic MSC (PM) with either overexpression or knockdown of TP53INP1, or activation/inhibition of p53 signaling pathway. RESULTS: Our results showed that miR-155 promoted proliferation, migration, inflammatory response and metabolite levels of MSC, while inhibiting apoptosis. In comparison to the MSC from normal subjects, the glycolysis levels were increased in PM. GO and KEGG analyses indicated that TP53INP1 was miR-155 target gene with negative regulation of cellular metabolic process. Moreover, miR-155 promoted glycolysis of PM by negative regulation of TP53INP1/p53 signaling pathway. CONCLUSIONS: MiR-155 could promote glycolysis via targeting of TP53INP1 in PM. These findings suggest a pathogenic role of miR-155 in metabolic abnormalities in psoriasis.

MiR-205-5p promotes lung cancer progression and is valuable for the diagnosis of lung cancer.

BACKGROUND: MicroRNAs (miRNAs) function as potential diagnostic biomarkers in various cancers. This study aimed to evaluate the roles of miR-205-5p in lung cancer progression and diagnosis. MATERIALS AND METHODS: MiR-205-5p was detected by quantitative real-time PCR. The effect of miR-205-5p on cell proliferation and metastasis was estimated by MTT and flow cytometry. The expression of TP53INP1 and related genes was analyzed by immunoblotting. The diagnostic value of miR-205-5p was analyzed using receiver operating characteristic (ROC) curve analysis, sensitivity, and specificity. RESULTS: The miR-205-5p was increased in lung cancer tissues. MiR-205-5p mimics were promoted but its inhibitor suppressed cell proliferation and metastasis compared with control treatment in vitro and in vivo. By regulating the 3' untranslated region, miR-205-5p could negatively regulate TP53INP1 expression, which further inhibited the expression of RB1 and P21, but increased that of cyclinD1. Moreover, the serum miR-205-5p levels of patients with lung cancer were significantly higher than those of normal controls, and they were correlated with patients' gender, drinking status, and clinical stage. The area under the ROC curve of serum miR-205-5p in the diagnosis of non-small-cell lung cancer was 0.8250, respectively. The finding supported its possession of high diagnostic efficiency for lung cancer. CONCLUSIONS: MiR-205-5p promoted lung cancer cell proliferation and metastasis by negatively regulating the novel target TP53INP1, which further affected the expression of P21, RB1, and cyclin D1. Serum miR-205-5p is a novel and valuable biomarker for lung cancer diagnosis.

MircoRNA-29a in Astrocyte-derived Extracellular Vesicles Suppresses Brain Ischemia Reperfusion Injury via TP53INP1 and the NF-κB/NLRP3 Axis.

Brain ischemia reperfusion injury (BIRI) is defined as a series of brain injury accompanied by inflammation and oxidative stress. Astrocyte-derived extracellular vesicles (EVs) are importantly participated in BIRI with involvement of microRNAs (miRs). Our study aimed to discuss the functions of miR-29a from astrocyte-derived EVs in BIRI treatment. Thus, astrocyte-derived EVs were extracted. Oxygen and glucose deprivation (OGD) cell models and BIR rat models were established. Then, cell and rat activities and pyroptosis-related protein levels in these two kinds of models were detected. Functional assays were performed to verify inflammation and oxidative stress. miR-29a expression in OGD cells and BIR rats was measured, and target relation between miR-29a and tumor protein 53-induced nuclear protein 1 (TP53INP1) was certified. Rat neural function was tested. Astrocyte-derived EVs improved miR-29a expression in N9 microglia and rat brains. Astrocyte-derived EVs inhibited OGD-induced injury and inflammation in vitro, reduced brain infarction, and improved BIR rat neural functions in vivo. miR-29a in EVs protected OGD-treated cells and targeted TP53INP1, whose overexpression suppressed the protective function of EVs on OGD-treated cells. miR-29a alleviated OGD and BIRI via downregulating TP53INP1 and the NF-κB/NLRP3 pathway. Briefly, our study demonstrated that miR-29a in astrocyte-derived EVs inhibits BIRI by downregulating TP53INP1 and the NF-κB/NLRP3 axis.

Hypoxic ucMSC-secreted exosomal miR-125b promotes endothelial cell survival and migration during wound healing by targeting TP53INP1.

A hypoxic microenvironment is a common feature of skin wounds. Our previous study demonstrated that three-dimensional coculture of umbilical cord-derived mesenchymal stem cells (ucMSCs) and endothelial cells facilitates cell communication and host integration in skin tissue engineering. Here, we aimed to identify the mechanism by which ucMSCs affect endothelial cells under hypoxic conditions after skin injury. We demonstrate that hypoxia enhances the exosome-mediated paracrine function of ucMSCs, which increases endothelial cell proliferation and migration. In a mouse full-thickness skin injury model, ucMSC-derived exosomes can be taken up by endothelial cells and accelerate wound healing. Hypoxic exosomes lead to a better outcome than normoxic exosomes by promoting proliferation and inhibiting apoptosis. Mechanistically, microRNA-125b (miR-125b) transcription is induced by hypoxia in ucMSCs. After being packaged into hypoxic exosomes and transported to endothelial cells, miR-125b targets and suppresses the expression of tumor protein p53 inducible nuclear protein 1 (TP53INP1) and alleviates hypoxia-induced cell apoptosis. Inhibition of miR-125b-TP53INP1 interaction attenuates the protective effect of hypoxic exosomes. Moreover, artificial agomiR-125b can accelerate wound healing in vivo. Our findings reveal communication between ucMSCs and endothelial cells via exosomal miR-125b/TP53INP1 signaling in the hypoxic microenvironment and present hypoxic exosomes as a promising therapeutic strategy to enhance cutaneous repair.

FOXO1 mediates hypoxia-induced G0/G1 arrest in ovarian somatic granulosa cells by activating the TP53INP1-p53-CDKN1A pathway.

The development of ovarian follicles constitutes the foundation of female reproduction. The proliferation of granulosa cells (GCs) is a basic process required to ensure normal follicular development. However, the mechanisms involved in controlling GC cell cycle are not fully understood. Here, by performing gene expression profiling in the domestic pig (Sus scrofa), we showed that cell cycle arrest at G0/G1 phase is highly correlated with pathways associated with hypoxic stress and FOXO signalling. Specifically, the elevated proportion of GCs at the arrested G0/G1 phase was accompanied by increased nuclear translocation of FOXO1 under conditions of hypoxia both in vivo and in vitro. Furthermore, phosphorylation of 14-3-3 by the JNK kinase is required for hypoxia-mediated FOXO1 activation and the resultant G0/G1 arrest. Notably, a FOXO1 mutant without DNA-binding activity failed to induce G0/G1 arrest of GCs during hypoxia. Importantly, we identified a new target gene of FOXO1, namely TP53INP1, which contributes to suppression of the G1-S cell cycle transition in response to hypoxia. Furthermore, we demonstrated that the inhibitory effect of the FOXO1-TP53INP1 axis on the GC cell cycle is mediated through a p53-CDKN1A-dependent mechanism. These findings could provide avenues for the clinical treatment of human infertility caused by impaired follicular development.

MicroRNA-155-5p promotes tumor progression and contributes to paclitaxel resistance via TP53INP1 in human breast cancer.

MicroRNAs (miRNAs/miRs) are small, non-coding RNAs that are reported to serve numerous important regulatory functions; however, the role of miRNAs in regulating breast cancer cell biology remains poorly understood. Accumulating evidence has demonstrated that miRNAs orchestrate multiple cellular functions and serve crucial roles in cell differentiation and cancer development, either by acting as tumor suppressors or oncogenes. In particular, miR-155-5p expression levels have been found to be upregulated and serve as a prognostic marker in numerous types of solid cancer, including human breast cancer. More than half of patients with breast cancer benefit from treatment with adjuvant paclitaxel chemotherapy following the early postoperative period. Despite the initial response to intensive combination chemotherapy, the majority of most patients will eventually acquire resistance to the drug and succumb to their disease. Therefore, further investigations into the association between miRNAs and the mechanism of paclitaxel resistance are required. The results of the present study revealed a strong positive association between miR-155-5p expression levels and the paclitaxel resistance, as the expression levels of miR-155-5p were upregulated in resistant cells. MiR-155-5p was further validated to regulate paclitaxel resistance using gain- and loss-of-function experiments. TP53INP1 was identified as a direct target gene of miR-155-5p by combining the results from the prediction algorithm based on free energy minimization and reverse transcription-quantitative PCR (qRT-PCR) analysis. Also, miR-155-5p was suggested to be a key regulator of paclitaxel resistance in tumor cells, as it increased cell viability and motility, and promoted resistance to paclitaxel-induced apoptosis. The transfection with miR-155-5p inhibitors re-sensitized the paclitaxel-resistant breast cancer cells, while the overexpression of miR-155-5p led to an increase in the resistance to paclitaxel. Furthermore, the overexpression of the target gene, TP53INP1, contributed to the re-sensitivity of drug-resistant cells to paclitaxel. The subsequent combination of the knockdown of miR-155-5p and the overexpression of TP53INP1 conferred paclitaxel sensitivity in resistant cells. These results may enhance the understanding of the molecular mechanisms underlying breast cancer progression and resistance to chemotherapy, and suggested that miR-155-5p or TP53INP1 may serve as novel therapeutic approaches to combat resistance to therapy, as well as the proliferation and evasion of apoptosis in breast cancer.

MicroRNA-1323 serves as a biomarker in gestational diabetes mellitus and aggravates high glucose-induced inhibition of trophoblast cell viability by suppressing TP53INP1.

Gestational diabetes mellitus (GDM) leads to poor pregnancy outcomes, and microRNAs (miRNAs/miRs) have been suggested to be associated with GDM, but the pathological mechanisms remain unclear. The present study aimed to investigate the diagnostic value of miR-1323 in GDM patients and its effects on trophoblast cell viability. Additionally, the present study investigated the correlation between miR-1323 and TP53INP1 to understand the pathological mechanism of GDM progression. Reverse transcription-quantitative polymerase chain reaction was used to detect the miR-1323 expression and TP53INP1 mRNA expression. The diagnostic value of serum miR-1323 was evaluated by receiver operating characteristic analysis. HTR-8/SVneo and BeWo cells were treated with high glucose (HG) to construct cell models of GDM, and trophoblast cell viability was assessed using an MTT assay. The protein expression of TP53INP1 was detected by western blot analysis. The correlation between miR-1323 and TP53INP1 was investigated by luciferase reporter assay. The miR-1323 expression was increased in patients with GDM, which had relatively high diagnostic accuracy for GDM screening and was positively correlated with fasting blood glucose in patients GDM. HG upregulated the miR-1323 expression and inhibited trophoblast cell viability. Overexpression of miR-1323 significantly inhibited the viability of HG-induced trophoblast cells. TP53INP1, a target gene of miR-1323, was negatively correlated with miR-1323. TP53INP1 overexpression reversed the inhibitory effect of miR-1323 overexpression on the viability of HG-treated trophoblast cells. Increased levels of serum miR-1323 may be a diagnostic biomarker for GDM. Additionally, miR-1323 may inhibit trophoblast cell viability by inhibiting TP53INP1, suggesting that it may be a potential therapeutic target for GDM.

LncRNA SNHG15 Knockdown Protects Against OGD/R-Induced Neuron Injury by Downregulating TP53INP1 Expression via Binding to miR-455-3p.

Cerebral ischemia-reperfusion (I/R) injury is the common symptom of ischemic stroke, which poses a heavy burden to human health. Long non-coding RNA (lncRNA) is indicated to be a critical regulator in cerebral ischemia. This study aims to reveal the effects of lncRNA small nucleolar RNA host gene 15 (SNHG15) on oxygen-glucose deprivation and reoxygenation (OGD/R)-induced neuron injury and underlying mechanism. The expression levels of SNHG15, microRNA-455-3p (miR-455-3p) and tumour protein p53 inducible nuclear protein 1 (TP53INP1) mRNA were determined by quantitative real time polymerase chain reaction in P12 cells. The protein levels of TP53INP1, cleaved caspase-3, caspase-3, B-cell lymphoma-2 and BCL2-associated x protein (Bax) were detected by western blot in P12 cells. Cell viability and apoptosis were revealed by cell counting kit-8 assay and flow cytometry analysis, respectively, in P12 cells. Caspase-3 activity, the levels of tumor necrosis factor-α and interleukin-1ß and the production of reactive oxygen species (ROS) were severally determined by caspase-3 activity assay, Enzyme-linked immunosorbent assay and ROS detection assay in P12 cells. The binding relationship between miR-455-3p and SNHG15 or TP53INP1 was predicted by starbase online database, and identified by dual-luciferase reporter, RNA pull-down or RNA immunoprecipitation assay. SNHG15 expression and the mRNA and protein levels of TP53INP1 were dramatically upregulated, while miR-455-3p expression was apparently downregulated in OGD/R-induced PC12 cells. SNHG15 silencing hindered the effects of OGD/R treatment on cell viability, apoptosis, inflammation and oxidative in PC12 cells; however, these impacts were restored after miR-455-3p inhibitor transfection. Additionally, SNHG15 acted as a sponge of miR-455-3p and miR-455-3p bound to TP53INP1. SNHG15 contributed to OGD/R-induced neuron injury by regulating miR-455-3p/TP53INP1 axis, which provided a novel insight to study lncRNA-directed therapy in ischemia stoke.

MicroRNA-155-5p Contributes to 5-Fluorouracil Resistance Through Down-Regulating TP53INP1 in Oral Squamous Cell Carcinoma.

The anticancer drug 5-fluorouracil (5-FU) resistance is a major obstacle to reducing the effectiveness of cancer treatment, and its detailed mechanism has not been fully elucidated. Here, in 5-FU-resistant human oral squamous cell carcinoma (OSCC) HSC3 cells (HSC3/5-FU), the levels of 21 miRNA candidates were detected using RT-PCR and miR-155-5p level increased strikingly in HSC3/5-FU cells compared to HSC3 cells. Compared with HSC3 cells, the CCK-8 assay showed that the HSC3/5-FU cells transfected with miR-155-5p inhibitors decreased 5-FU IC50. Ectopic expression of miR-155-5p in HSC3 and HSC4 cells increased 5-FU IC50 (CCK-8 assay), migration (wound-healing and transwell assays) and invasion (transwell assay) abilities. Seven miR-155-5p target candidates were discovered by miRNA prediction algorithms (miRDB, Targetscan, and miRWalk), and the RT-PCR results showed that in HSC3/5-FU cells TP53INP1 was of the lowest mRNA expression level compared with HSC3 cells. The RT-PCR and Western blotting assays showed that ectopic expression of miR-155-5p in HSC3 and HSC4 cells decreased TP53INP1 expression level. Furthermore, the luciferase reporter and RNA pull-down assays determined the interference effect of miR-155-5p on TP53INP1 expression. The enhancement of cell viability (CCK-8 assay), migration (wound-healing and transwell assays) and invasion (transwell assay) by miR-155-5p after 5-FU treatment was reversed by TP53INP1 overexpression. After treatment with 5-FU, HSC3-miR-155-5p tumor-bearing nude mice presented growing tumors, while HSC3-TP53INP1 group possessed shrinking tumors. In conclusion, these results lead to the proposal that miR-155-5p enhances 5-FU resistance by decreasing TP53INP1 expression in OSCC.

Corrigendum: Downregulation of HMGA1 Mediates Autophagy and Inhibits Migration and Invasion in Bladder Cancer via miRNA-221/TP53INP1/p-ERK Axis.

[This corrects the article DOI: 10.3389/fonc.2020.00589.].

miR-96 regulates liver tumor-initiating cells expansion by targeting TP53INP1 and predicts Sorafenib resistance.

Liver tumor-initiating cells (T-ICs) contribute to tumorigenesis, progression, recurrence and drug resistance of hepatocellular carcinoma (HCC). However, the underlying mechanism for the propagation of liver T-ICs remains unclear. In the present study, our finding shows that miR-96 is upregulated in liver T-ICs. Functional studies revealed that forced miR-96 promotes liver T-ICs self-renewal and tumorigenesis. Conversely, knockdown miR-96 inhibits liver T-ICs self-renewal and tumorigenesis. Mechanistically, miR-96 downregulates TP53INP1 via its mRNA 3'UTR in liver T-ICs. Furthermore, the miR-96 expression determines the responses of hepatoma cells to sorafenib treatment. Analysis of patient cohorts and patient-derived xenografts (PDXs) further demonstrate that the miR-96 may predict sorafenib benefits in HCC patients. Our findings revealed the crucial role of the miR-96 in liver T-ICs expansion and sorafenib response, rendering miR-96 as an optimal target for the prevention and intervention of HCC.

LncRNA NR_027471 Functions as a ceRNA for miRNA-8055 Leading to Suppression of Osteosarcoma by Regulating the Expression of TP53INP1.

Osteosarcoma is a malignancy with high aggressiveness and poor prognosis, which occurs mainly in children. The therapeutic strategy against osteosarcoma includes surgery combined with chemotherapy and radiotherapy. Although the treatment of osteosarcoma has been improved in recent years, there is a large proportion of patients with incurable osteosarcoma. Investigation of the mechanism of osteosarcoma progression would be of great help in discovering therapeutic targets for this disease. Long non-coding RNAs play critical roles in the pathogenesis of different types of cancer. The current study showed that long non-coding RNA NR_027471 was downregulated in osteosarcoma cells. In vitro and in vivo studies indicated that upregulation of NR_027471 impeded the viability, proliferation, and invasion of osteosarcoma, as well as induced cell cycle arrest at G1. In addition, binding of miR-8055 to NR_027471 was demonstrated, thereby influencing the expression of tumor protein p53 inducible nuclear protein 1 (TP53INP1). Knockdown of NR_027471 promoted epithelial-mesenchymal transition by inhibiting E-cadherin and increasing the expression of zinc finger E-box-binding homeobox 1 (ZEB1), Snail, and fibronectin. These results suggested that overexpression of NR_027471 upregulated TP53INP1 by sponging to miR-8055, leading to suppression of osteosarcoma cell proliferation and progression.

Long non-coding RNA MEG3 promotes cataractogenesis by upregulating TP53INP1 expression in age-related cataract.

Age-related cataract (ARC) is the leading cause of visual impairment or even blindness among the aged population globally. Long non-coding RNA (LncRNA) has been proven to be the potential regulator of ARC. The latest study reveals that maternally expressed gene 3 (MEG3) promotes the apoptosis and inhibits the proliferation of multiple cancer cells. However, the expression and role of MEG3 in ARC are unclear. In this study, we investigated the effects of MEG3 in ARC and explored the regulatory mechanisms underlying these effects. We observed that MEG3 expression was up-regulated in the age-related cortical cataract (ARCC) lens capsules and positively correlated with the histological degree of ARCC. The pro-apoptosis protein, active caspase-3 and Bax increased in the anterior lens capsules of ARCC tissue, while the anti-apoptotic protein Bcl-2 decreased compared to normal lens. Knockdown of MEG3 increased the viability and inhibited the apoptosis of LECs upon the oxidative stress induced by H2O2. MEG3 was localized in both nucleus and cytoplasm in LECs. MEG3 facilitated TP53INP1 expression via acting as miR-223 sponge and promoting P53 expression. Additionally, TP53INP1 knockdown alleviated H2O2-induced lens turbidity. In summary, MEG3 promoted ARC progression by up-regulating TP53INP1 expression through suppressing miR-223 and promoting P53 expression, which would provide a novel insight into the pathogenesis of ARC.