Glycyrrhiza glabra suppresses nasopharyngeal carcinoma cell proliferation through inhibiting the expression of lncRNA, AK027294.

Glycyrrhiza glabra is considered as potential drug for nasopharyngeal carcinoma (NPC). However, whether the long noncoding RNAs' (lncRNAs) contributes to the anti-cancer function of this herb is unknown. In present study, we analyzed the differential expression of lncRNA between G. glabra-treated and untreated C666-1 cells. Out of those tumor-related lncRNAs, AK027294 had a strongest down-regulation upon G. glabra treatment. Knockdown of AK027294 suppresses the proliferation of C666-1 cells by inducing the apoptosis. Moreover, either G. glabra treatment or knockdown of AK027294 significantly increases the production of EZH1 (Enhancer of zeste 1 polycomb repressive complex 2 subunit). Collectively, we have identified a potential mechanism that the down-regulation of AK027294 contributes to the anti-cancer function of G. glabra and also provide the potential inter-relationship between AK027294 and EZH1.

Anti-tumor effect of HOTAIR-miR-613-SNAI2 axis through suppressing EMT and drug resistance in laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC) is the main pathological type of laryngeal cancer, which attacks the head and neck. Our present study aims to investigate the effect of long non-coding RNA (LncRNA) HOX transcript antisense RNA (HOTAIR) on epithelial mesenchymal transition (EMT) and drug resistance in LSCC. Firstly, the level of HOTAIR was found to be overexpressed in LSCC tissues compared with normal healthy tissues. Then, increased EMT and drug resistance were suppressed by specific HOTAIR shRNA effectively in LSCC cell lines. Besides, miR-613 was predicted to be a target of HOTAIR through bioinformatics analysis. Meanwhile, we found that a down-regulated level of miR-613 could be increased by HOTAIR shRNA and suppressed by LncRNA HOTAIR transfection in LSCC cells. The targeting relationship between miR-613 and HOTAIR was further demonstrated by a luciferase report assay. What is more, the inhibiting effect of HOTAIR shRNA on EMT and drug resistance was obviously abolished by the miR-613 inhibitor. Moreover, SNAI2, a critical regulator of EMT, was predicted as a target of miR-613 through bioinformatics analysis and luciferase report assays. As expected, the level of SNAI2 could be suppressed by HOTAIR shRNA and increased by the miR-613 inhibitor. Additionally, we discovered that SANI2 shRNA had similar inhibiting effect on EMT and drug resistance with HOTAIR shRNA in LSCC cells. Finally, the in vivo experiment further demonstrated that HOTAIR shRNA restricted tumor growth, EMT and drug resistance. Additionally, HOTAIR shRNA transfection could also increase the level of miR-613 and decrease the level of SNAI2 in vivo. Taken together, our research for the first time revealed the effect of the HOTAIR-miR-613-SNAI2 axis on EMT and drug resistance in LSCC, providing new targets for LSCC diagnosis and treatment.

[An experimental study of mucociliary clearance of trachea reconstructed with free jejunum].

OBJECTIVE: To investigate tracheal mucociliary transport change after reconstructed with free jejunum. METHODS: Twelve canine models of extensive circumferential tracheal defects reconstructed with revascularized jejuno combined with Ni-Ti alloy mesh tube were established. Every canine model was marked in cervical skin projecting the lower resected margin of trachea lumen and was injected 50% barium sulfate mucilage as a tracer into the trachea lumen under bronchoscopy. Record the time from tracer injected into trachea lumen to its arriving glottis (mucociliary transit time, MTT) and the length from tracer injected into trachea lumen to glottis (mucociliary transport length, MTL). Mucociliary transit rate (MTR), as MTL/ MTT, was calculated. The same procedure was performed at preoperative and postoperative 7th day, 1 month, 3 months and 6 months. RESULTS: There were statistical significance between preoperative MTR and 1 month postoperative MTR (P < 0.05). There were no differences between preoperative MTR and postoperative MTR at the 7th day, 1 month, 3 months and 6 months. There were also no differences between postoperative MTR at the 7th day and 1 month, 3 months and 6 months. CONCLUSION: In new tracheal tract reconstructed with free jejunum, MTR becomes normal at 3 months postoperatively.

[Experimental reconstruction of the canine trachea with shape-memory titanium-nickel alloy stent coupled with free jejunal graft].

OBJECTIVE: To explore the reconstruction method of extensive circumferential tracheal defects longer than 6.0 cm and evaluate the influence on pulmonary function from jejunal secretion. METHODS: Jejunal secretion model without extraneous nerve were established. 10 mongrel dogs were randomly divided into two groups. In group A, the nude stent made by shape-memory titanium-nickel alloy (SMA stent) was placed in the interior of the intestinal lumen. In group B, the SMA stent with silicone membrane was placed in the interior of the intestinal lumen. The secretion and histological chance of these jejunal were observed regularly. The cervical tracheal segment (6.5 cm) was replaced by the intestinal graft. In group C (6 mongrel dogs), the nude stent made by SMA stent was placed in the interior of the intestinal lumen. In group D (6 mongrel dogs and 6 Beagle dogs), the SMA stent with silicone membrane was placed in the interior of the intestinal lumen, the nude "C-shaped" SMA stent was placed out of the intestinal lumen, and the silicone stent was removed the fourth week after operation. In group C and group D, endoscopic and histological examinations were performed between the first week and eighth month. RESULTS: The secretory peak of Jejunal secretion model without extraneous nerve ranged from the first day to seventh day after operation. The jejunal secretion reduced gradually from 7th days after operation. The jejunal secretion remained steady after postoperative two months. In group C, endoscopic examination showed heavy proliferation of granulation in the tracheo-intestinal anastomosis. 4 dogs died between seventh day to second month. In group D, one dog died from ileus third month after operation. The other all survived operation. Gentle pneumonia happened to some dogs during 1-2 months after operation by X-ray examination. No one died of pneumonia result from hypersecretion. CONCLUSIONS: Reconstruction of the canine trachea with SMA stent with silicone membrane placed in the interior of the intestinal lumen together with the nude "C-shaped" SMA stent placed out of the intestinal lumen achieve satisfactory effect, the reconstructed trachea remain unblocked and this method of tracheal reconstruction may be relatively perfect and be expected for clinical application in future. The jejunal secretion didn't have severe influence on pulmonary function of experimental canine and couldn't cause experimental canine death.