MicroRNA-663 antagonizes apoptosis antagonizing transcription factor to induce apoptosis in epithelial cells

Phospho-Smad3L promotes progression of hepatocellular carcinoma through decreasing miR-140-5p level and stimulating epithelial-mesenchymal transition

BACKGROUND

The transforming growth factor β (TGF-β) activates JNK, phosphorylates Smad3 to linker-phosphorylated Smad3 (pSmad3L), resulting in liver tumorigenesis. However, the effect of pSmad3L on hepatocellular carcinoma (HCC) prognosis is obscure.

AIM

To detect the effect of pSmad3L on HCC prognosis and investigate the mechanism.

METHODS

The expressions of pSmad3L, E-cadherin, vimentin and MicroRNA-140-5p (miR-140-5p) were detected by using immunohistochemistry, immunofluorescence and in situ hybridization. Next, the relationships of pSmad3L and HCC patients' prognoses, pSmad3L and EMT markers, pSmad3L and miR-140-5p were analyzed using Spearman's rank correlation test. JNK/pSmad3L specific inhibitor SP600125 or Smad3 mutant plasmid was used to suppress JNK/pSmad3L pathway, and QPCR assay was performed to investigate the effect of pSmad3L on miR-140-5p level. The proliferation and invasion of hepatoma cells were observed using colony formation assay and transwell assay.

RESULTS

We demonstrated that patient with high level of pSmad3L predicted poor prognosis. Next, we verified that pSmad3L promoted EMT of hepatoma cells in vivo and in vitro. In order to investigate the mechanism, we verified a negative correlation between pSmad3L and miR-140-5p, which was an EMT inhibitor, in the liver tissues of HCC patient and diethylnitrosamine (DEN)-induced rat HCC model. We further used SP600125 or pSmad3L mutant plasmid to decrease pSmad3L level of hepatoma cells, and inhibition of pSmad3L increased miR-140-5p level and suppressed EMT of hepatoma cells.

CONCLUSIONS

JNK/pSmad3L pathway induces EMT by inhibiting miR-140-5p in HCC progression.

Apoptosis-antagonizing transcription factor is involved in rat post-traumatic epilepsy pathogenesis

The present study aimed to explore the pathogenesis behind post-traumatic epilepsy (PTE). In the present study, a chloride ferric injection-induced rat PTE model was established. The expression levels of apoptosis-antagonizing transcription factor (AATF), cleaved caspase-3, p53, Bcl-2 and Bax were measured by western blotting or immunofluorescence staining (IF). The expression of AATF in vivo was downregulated by microinjection of lentiviral-mediated short-hairpin RNA. Compared with control and sham groups, at day 5 after PTE, neuron apoptosis was significantly increased and the expression levels of AATF, p53, cleaved caspase-3 and Bax were significantly upregulated. In addition, IF revealed co-localization of AATF and cleaved caspase-3 in the cortex. Additionally, AATF was expressed mainly in neurons and astrocytes. Following AATF inhibition, the expression levels of p53 and cleaved caspase-3 were significantly reduced as compared with the control group. Taken together, these findings suggested that following PTE, AATF is involved in neuronal apoptosis and may serve as a potential target for its alleviation.

An injectable hydrogel-formulated inhibitor of prolyl-4-hydroxylase promotes T regulatory cell recruitment and enhances alveolar bone regeneration during resolution of experimental periodontitis

The hypoxia-inducible factor 1α (HIF-1α) is critically involved in tissue regeneration. Hence, the pharmacological prevention of HIF-1α degradation by prolyl hydroxylase (PHD) under normoxic conditions is emerging as a promising option in regenerative medicine. Using a mouse model of ligature-induced periodontitis and resolution, we tested the ability of an injectable hydrogel-formulated PHD inhibitor, 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (1,4-DPCA/hydrogel), to promote regeneration of alveolar bone lost owing to experimental periodontitis. Mice injected subcutaneously with 1,4-DPCA/hydrogel at the onset of periodontitis resolution displayed significantly increased gingival HIF-1α protein levels and bone regeneration, as compared to mice treated with vehicle control. The 1,4-DPCA/hydrogel-induced increase in bone regeneration was associated with elevated expression of osteogenic genes, decreased expression of pro-inflammatory cytokine genes, and increased abundance of FOXP3⁺ T regulatory (Treg) cells in the periodontal tissue. The enhancing effect of 1,4-DPCA/hydrogel on Treg cell accumulation and bone regeneration was reversed by AMD3100, an antagonist of the chemokine receptor CXCR4 that mediates Treg cell recruitment. In conclusion, the administration of 1,4-DPCA/hydrogel at the onset of periodontitis resolution promotes CXCR4-dependent accumulation of Treg cells and alveolar bone regeneration, suggesting a novel approach for regaining bone lost due to periodontitis.

MicroRNA‑103a‑3p promotes metastasis by targeting TPD52 in salivary adenoid cystic carcinoma

Salivary adenoid cystic carcinoma (SACC) exhibits slow continuous growth, frequent local recurrences and a high incidence of blood metastasis, with advanced lung metastasis frequently occurring and being among the primary causes of mortality. MicroRNAs (miR) serve a significant role in the initiation and development of cancer and may be tumour‑specific molecular targets. However, the role of miR‑103a‑3p in SACC remains largely unknown. In the present study, the expression levels of miR‑103a‑3p and tumour protein D52 (TPD52) were detected by reverse transcription‑quantitative PCR. In addition, wound‑healing assays, Transwell assays and mouse models of lung metastasis were used to investigate the biological functions exerted by miR‑103a‑3p. The present results suggested that miR‑103a‑3p expression was significantly upregulated in SACC samples. Gain‑of‑function and loss‑of‑function studies in SACC cells demonstrated that miR‑103a‑3p acted as an oncogene by promoting tumour cell migration in vitro and lung metastasis in vivo. Dual‑luciferase reporter gene assays indicated that miR‑103a‑3p exerted its regulatory functions by binding to the 3' untranslated region of TPD52 mRNA. TPD52 overexpression rescued the effect of miR‑103a‑3p on promoting SACC cell migration, suggesting that miR‑103a‑3p acted as an oncogene to promote cancer metastasis by directly targeting TPD52. Thus, the newly identified miR‑103a‑3p/TPD52 axis contributes to the understanding of SACC pathogenesis, providing insights into the identification of novel biomarkers or potential therapeutic targets in SACC.

Long non-coding RNA ROR sponges miR-138 to aggravate hypoxia/reoxygenation-induced cardiomyocyte apoptosis via upregulating Mst1

BACKGROUND

Hypoxia/reoxygenation (H/R) injury of cardiomyocytes causes an irreversible damage to heart and largely results in acute myocardial infarction. Study has indicated lncRNA ROR aggravates myocardial ischemia/reperfusion (I/R) injury. Also, lncRNA ROR sponges miR-138 to promote osteogenesis. MiR-138 involves in hypoxic pulmonary vascular remodelling by targeting Mst1. However, the interaction between lncRNA ROR, miR-138 and Mst1 involved in myocardial H/R injury is still unknown.

METHODS

H9C2 cells were used to establish H/R injury model. The expression levels of lncRNA ROR and miR-138 were modified by transfection with the miR-138 mimics or lncRNA ROR overexpression plasmid. MTT and flow cytometry analysis were performed to detect cell proliferation and apoptosis. Dual luciferase reporter assay was used to determine interaction between lncRNA ROR and miR-138 or miR-138 and Mst1. Expression levels of lncRNA ROR, miR-138, Mst1 and apoptosis-related markers were determined by qRT-PCR or western blotting.

RESULTS

LncRNA ROR was significantly up-regulated, while miR-138 was obviously down-regulated in H/R-induced injury of H9C2 cells. Furthermore, miR-138 overexpression alleviated cardiac cell apoptosis induced by H/R injury. Mst1 was revealed to be a target of miR-138 and negatively regulated by miR-138. Mst1 overexpression reversed the protective effects of miR-138 on H/R injury of H9C2 cells. LncRNA ROR was identified as a sponge for miR-138. MiR-138 could protect H9C2 cells form H/R injury induced by lncRNA ROR overexpression.

CONCLUSION

Our study provides that lncRNA ROR sponges miR-138 to aggravate H/R-induced myocardial cell injury by upregulating the expression of Mst1.

Who is who in oral cancer?

Great attention has been attached to explore the association between oral bacteria and oral cancer. Recently, four common inhabitants of oral cavity, Porphyromonas gingivalis, Fusobacterium nucleatum, Treponema denticola and Streptococcus anginosus, have been identified as potential etiologic bacterial agents for oral carcinogenesis. They might promote the oncogenesis and progression of oral cancer by induction of chronic inflammation, enhancement of migration and invasiveness, inhibition of cell apoptosis, augment of cell proliferation, suppression of immune system and production of carcinogenic substances. Thus, this review will focus on the possible mechanisms of these oral bacteria contributing to occurrence and development of oral cancer, and the potential clinical implications of utilizing oral bacteria on the diagnosis, prevention and treatment of oral cancer will be discussed.

IFN-β secretion is through TLR3 but not TLR4 in human gingival epithelial cells

The oral cavity is home for a plethora of bacteria and viruses. Epithelial barriers encounter these micro-organisms and recognize them via pathogen recognition receptors (PRRs) that instigate antibacterial and antiviral responses. We and others have shown that human gingival epithelial cells (HGECs) express PRRs to defend invading pathogens. Among these PRRs, TLR2, TLR3 and TLR4 are highly expressed in HGECs and appear to be important based on our previous findings. IFN-β is one of the major type 1 interferons induced to defend viral attack. In this report, we sought to dissect TLR3 and TLR4 mediated secretion of IFN-β in HGECs. We stimulated HGECs with ultrapure LPS (TLR4 ligand) and Poly I:C (TLR3 ligand) for 24 h and supernatant was used to determine IFN-β secretion. We show that cells treated with Poly I:C induced IFN-β secretion but not cells treated with LPS. In addition, silencing of TLR3 prior to Poly I:C stimulation significantly downregulated IFN-β secretion. On the contrary, overexpression of MD2 and TLR4 in HGECs restored IFN-β secretion. Upon further evaluation, we found that TLR3 stimulation but not TLR4 induced the phosphorylation of interferon regulatory factor 3 (IRF3), which is critical for IFN-β secretion. We conclude that IFN-β secretion is through TLR3 and not via TLR4 in HGECs.