Construction of an EMT-related lncRNA prognostic signature for lung adenocarcinoma and functional verification of its hub gene LINC01615.

BACKGROUND: The epithelial-mesenchymal transition (EMT) plays a vital role in the progression of lung adenocarcinoma (LUAD). Long non-coding RNAs (lncRNAs) participate in the EMT process as an important regulatory factor and have the potential to serve as prognostic biomarkers. We aimed to construct a novel lncRNA prognostic signature for LUAD based on EMT-related lncRNAs, identify EMT-related hub lncRNA, and investigate its biological functions. METHODS: RNA-seq data, clinical and survival information were obtained from The Cancer Genome Atlas database. The EMT-related lncRNA prognostic signature (EMTscore) was constructed using the Least Absolute Shrinkage and Selection Operator Cox regression analysis. The efficiency of EMTscore in predicting the prognosis of LUAD was evaluated through the area under the time-dependent receiver operating characteristic (ROC) curves. The hub lncRNA of the prognostic signature was selected using a co-expression network map, and its effects on cell proliferation and metastasis were explored by in vitro experiments. RESULTS: We constructed a prognostic signature (EMTscore) containing 8 tumor-high expressed lncRNAs. The EMTscore performed well in predicting overall survival rates with AUC values of 0.708 at 5 years in the training set. EMTscore could independently predict the survival of LUAD, with HR = 4.011 (95% CI 2.430-6.622) in the multivariate Cox regression. Importantly, we identified LINC01615 as the hub lncRNA in the EMTscore and revealed that LINC01615 enhanced the proliferation, migration, and EMT of lung cancer cells. CONCLUSIONS: A new EMT-related lncRNA prognostic signature named EMTscore was developed, and LINC01615 was identified as the hub lncRNA of EMTscore. The hub lncRNA LINC01615 had an oncogenic biological function in LUAD.

The promotion of sestrin2/AMPK signaling by HIF-1α overexpression enhances the damage caused by acute myocardial infarction.

OBJECTIVE: Acute myocardial infarction (AMI), is a serious form of coronary heart disease. The present study sought to investigate the impact of HIF-1α on AMI, along with its fundamental mechanism. METHODS: Sprague-Dawley (SD) rats were used to conduct an AMI model. 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining was used examine the region of myocardial infract area at various time intervals. Protein expression levels were detected using western blotting. The rats were randomly divided into sham, model, negative control (NC), HIF-1α overexpression (HIF-1α-OE), and HIF-1α-OE+ si-sestrin2 groups. We examined the impact of HIF-1α overexpression on AMI rats using Haematoxylin-Eosin (H&E) staining, TTC staining, enzyme-linked immunosorbent assay (ELISA), TdT-mediated dUTP Nick-End Labeling (TUNEL) assay, and immunohistochemistry (IHC) staining. RESULTS: According to the TTC findings, the region affected by myocardial infarction reached its peak at day 14. Based on the results from the western blot analysis, the levels of HIF-1α and sestrin2 were found the minimum on day 28. Subsequently, we discovered that the overexpression of HIF-1α rescued the cardiac function parameters, improved the morphology of myocardial tissue, and mitigated inflammation. Furthermore, the overexpression of HIF-1α led to a reduction in the levels of MDA and an increase in the levels of SOD. Moreover, the overexpression of HIF-1α resulted in a decrease in cellular apoptosis. This result was confirmed by the expression levels of Bcl-2 and Bax. Nevertheless, the defensive impact of elevated HIF-1α expression was somewhat counteracted by the suppression of sestrin2. In terms of mechanism, the overexpression of HIF-1α enhanced the levels of sestrin2 and the protein adenosine monophosphate activated kinase (AMPK). CONCLUSION: Our research suggests that the overexpression of HIF-1α may rescue the damage to myocardial tissue, and this effect is associated with the sestrin2/AMPK signaling pathway. Our study provides a novel comprehension of the protective effects of HIF-1α overexpression on AMI.

Shenfu Administration Improves Cardiac Fibrosis in Rats With Myocardial Ischemia-Reperfusion Through Adenosine A2a Receptor Activation.

OBJECTIVE: Shenfu injection (SFI) is commonly used for cardiac dysfunction in China. Adenosine receptors have been reported to exert anti-fibrosis effects. The intent of this study was to evaluate that SFI attenuates cardiac fibrosis through activating of adenosine A2a receptor (A2aR) in rats with myocardial ischemia-reperfusion (MI/R). METHODS: Sprague Dawley male rats were randomly divided into five groups, nine rats in each group. Injections in all rat groups were carried out prior to reperfusion, and in the sham and MI/R groups, only vehicle was injected. Injections in the remaining group were as follows: 5 mL/kg in the SFI group; 15 mg/kg nicorandil in the A2R agonist group; and 5 mL/kg SFI plus 5 mg/kg MSX-3 in the SFI + A2aR antagonist group. Changes in cyclic adenosine monophosphate (cAMP) and the development of myocardial infarction and cardiac fibrosis were documented among the groups. Additionally, the levels of A2aR, collagen Ⅰ, collagen Ⅲ, fibronectin, and matrix metalloproteinase-9 (MMP-9) were measured. RESULTS: Following injection with SFI or nicorandil, the cAMP concentration, infarct area, and cardiac fibrosis induced by MI/R injury were significantly decreased (p < 0.05). Additionally, the levels of collagen Ⅰ, collagen Ⅲ, fibronectin, and MMP-9 were clearly suppressed by SFI or nicorandil when compared with the MI/R group (p<0.01). However, the protective effects of SFI were counteracted by MSX-3. A negative correlation between A2aR and collagen I and collagen III was found (p = 0.00). CONCLUSION: SFI activated the A2aR to reduce myocardial fibrosis caused by MI/R injury, which provided an underlying mechanism of action of SFI.

Polyphyllin I, a lethal partner of Palbociclib, suppresses non-small cell lung cancer through activation of p21/CDK2/Rb pathway in vitro and in vivo.

Cyclin-dependent kinases (CDKs) are hyperactive in many cancers and have served as cancer therapeutic targets for decades. Palbociclib (Palb) is the first approved CDK4/6 inhibitor to treat hormone receptor (HR)-positive, HER2-negative advanced breast cancer. Acquired drug resistance is one obstacle of Palb be utilized in other cancer. CDK2 compensation of CDK4/6 loss is one of the causes that cancer cells are resistant to Palb. Hence, targeting multiple CDKs could be a novel strategy to prevent the drug resistance of cancer cells and expand the application of Palb in other cancer. In this study, we initially indicated Polyphyllin I (PPI) significantly inhibits non-small lung cancer cell (NSCLC) proliferation, promotes cell apoptosis in vitro and in vivo. Mechanistically, PPI can inhibit Rb through the p21/CDK2/Rb signaling pathway in NSCLC. A combination of PPI and Palb exerts a significant synergistic anti-cancer ability on NSCLC. Of note, PPI can reverse Palb drug resistance. Herein, we first time demonstrated PPI can disturb CDK2 function through upregulation of p21. The PPI effect on CDK2 provides a choice for a chemotherapeutic strategy for the elimination of NSCLC. Our study highlighted the clinical significance of simultaneously blocking of CDK2 and CDK4/6 for NSCLC treatment.

Effects of Shenfu injection on myocardial adenosine receptors in rats with myocardial ischemia-reperfusion postconditioning.

OBJECTIVE: Shenfu injection (SFI) has been reported to have a protection against myocardial ischemia-reperfusion (MI/R) injury. However, the changes of adenosine receptors in MI/R postconditioning when pretreated with SFI are unclear. METHODS: Forty-five rats were randomly divided into sham group (sham), MI/R postconditioning group (MI/R-post), low-dose SFI group (1 mL/kg), middle-dose SFI group (2.5 mL/kg), and high-dose SFI group (5 mL/kg). In SFI groups, SFI was intravenously injected before reperfusion, and rats were treated with ischemic postconditioning after ischemia for 30 min. After 24 h of reperfusion, the levels of Ca2+ and cAMP in blood platelets were analyzed. Myocardial infarct volume and myocardial pathology were observed. The levels of adenosine receptor subtypes A1, A2b, and A3 in myocardium were analyzed using immunohistochemistry and Western blot. The oxidative stress-related indicators were also observed. RESULTS: Compared with the MI/R-post group, SFI ameliorated the MI/R injury by decreasing the myocardial infarct area, oxidative stress, and concentration of Ca2+ and cAMP (p < 0.01). Pretreatment with SFI enhanced the expression of adenosine receptors A1 and A2b in a dose manner compared with the MI/R-post group. In contrast, the levels of adenosine receptor A3 were increased after MI/R postconditioning compared with the sham group, and its expression continued to increase with the increase of SFI. Furthermore, the oxidative stress reduced with the concentrations of SFI. CONCLUSION: These results demonstrated that pretreatment with SFI might regulate the expression of adenosine receptors to improve the MI/R postconditioning.

Association between lumbar disc herniation and facet joint osteoarthritis.

BACKGROUND: This study was performed to investigate the association between lumbar disc herniation (LDH) and facet joint osteoarthritis (FJOA) using magnetic resonance imaging (MRI). METHODS: Between March 2012 and September 2018, a total of 441 segments from 394 patients with LDH were included in the study. LDH was classified according to the Michigan State University (MSU) classification, in which the degree of LDH is divided into 3 levels (expressed as 1, 2, and 3) and the location of LDH is divided into 4 zones (described as A, AB, B, and C). Bilateral FJOA was graded from 0 to 3 using the criteria introduced by Weishaupt et al., and bilateral facet orientations were measured on axial MRI slices. A mixed-effects ordinal logistic regression model was utilized to determine the potential factors that may be associated with FJOA, including sex, age, body mass index (BMI), segment, facet orientation and tropism, and the degree and location of LDH. RESULTS: In general, the prevalence of FJOA (grade ≥ 2) was 66.2% in LDH segments. For both the left and right sides, the degree of LDH was associated with the severity of FJOA (p < 0.01). Age and BMI were also associated with the severity of left and right FJOA (p = 0.002 and p < 0.001 for age, p < 0.001 and p = 0.003 for BMI, respectively), while segment, facet orientation, and facet tropism were not (p > 0.05 for all). Notably, MSU-B LDH was associated with greater odds of having more severe FJOA on the herniation side (left: p < 0.001, odds ratio (OR) = 2.714, 95% confidence interval (CI) = 1.583~4.650; right: p = 0.003, OR = 2.615, 95% CI = 1.405~4.870). However, other locations of LDH were not associated with the severity of FJOA (p > 0.05 for all). CONCLUSIONS: Both the degree of LDH and MSU-B LDH are associated with the severity of FJOA. The association between LDH and FJOA highlights the complexity of the etiology of FJOA.

Morphological changes of contralateral intervertebral foramen induced by cage insertion orientation after unilateral transforaminal lumbar interbody fusion.

BACKGROUND: This study was performed to investigate the morphological changes of contralateral intervertebral foramen (IVF) based on computed tomography images of patients with lumbar spinal stenosis after unilateral transforaminal lumbar interbody fusion (TLIF) and to compare the influence of different orientation of cage insertion on these changes. METHODS: This is a retrospective cohort study. Sixty-nine patients with lumbar spinal stenosis who had undergone single-level unilateral TLIF were retrospectively analyzed. The patients were divided into two groups according to the cage insertion orientation: the oblique group (o-group, 39 cases) and the transverse group (t-group, 30 cases). The morphological parameters of contralateral IVF were measured before and 6 months after the operation. Changes in these parameters were compared and analyzed between the two groups. The 6-month clinical outcomes of the two groups were also collected and analyzed. RESULTS: There was a significant difference in the rate of increase in the segmental angle (p < 0.01) between the two groups, the mean value of segmental angle increased by an average of 29.08% ± 14.93% in the o-group and 48.63% ± 12.01% in the t-group. Overall, the posterior disc height had a significant positive correlation with the foraminal height and area. In the o-group, however, an increase in the segmental angle resulted in a decrease in the foraminal area. No significant difference in clinical outcomes was found between the two groups. CONCLUSIONS: Compared with oblique cage insertion, transverse cage insertion could achieve greater restoration of segmental lumbar lordosis without decreasing contralateral foraminal dimensions.