Targeting the mitochondrial protein YME1L to inhibit osteosarcoma cell growth in vitro and in vivo.

Exploring novel diagnostic and therapeutic biomarkers is extremely important for osteosarcoma. YME1 Like 1 ATPase (YME1L), locating in the mitochondrial inner membrane, is key in regulating mitochondrial plasticity and metabolic activity. Its expression and potential functions in osteosarcoma are studied in the present study. We show that YME1L mRNA and protein expression is significantly elevated in osteosarcoma tissues derived from different human patients. Moreover, its expression is upregulated in various primary and immortalized osteosarcoma cells. The Cancer Genome Atlas database results revealed that YME1L overexpression was correlated with poor overall survival and poor disease-specific survival in sarcoma patients. In primary and immortalized osteosarcoma cells, silencing of YME1L through lentiviral shRNA robustly inhibited cell viability, proliferation, and migration. Moreover, cell cycle arrest and apoptosis were detected in YME1L-silenced osteosarcoma cells. YME1L silencing impaired mitochondrial functions in osteosarcoma cells, causing mitochondrial depolarization, oxidative injury, lipid peroxidation and DNA damage as well as mitochondrial respiratory chain complex I activity inhibition and ATP depletion. Contrarily, forced YME1L overexpression exerted pro-cancerous activity and strengthened primary osteosarcoma cell proliferation and migration. YME1L is important for Akt-S6K activation in osteosarcoma cells. Phosphorylation of Akt and S6K was inhibited after YME1L silencing in primary osteosarcoma cells, but was strengthened with YME1L overexpression. Restoring Akt-mTOR activation by S473D constitutively active Akt1 mitigated YME1L shRNA-induced anti-osteosarcoma cell activity. Lastly, intratumoral injection of YME1L shRNA adeno-associated virus inhibited subcutaneous osteosarcoma xenograft growth in nude mice. YME1L depletion, mitochondrial dysfunction, oxidative injury, Akt-S6K inactivation, and apoptosis were detected in YME1L shRNA-treated osteosarcoma xenografts. Together, overexpressed YME1L promotes osteosarcoma cell growth, possibly by maintaining mitochondrial function and Akt-mTOR activation.

Identification of lung adenocarcinoma subtypes and a prognostic signature based on activity changes of the hallmark and immunologic gene sets.

Background: Lung adenocarcinoma (LUAD) has a complex tumor heterogeneity. Our research attempts to clearness LUAD subtypes and build a reliable prognostic signature according to the activity changes of the hallmark and immunologic gene sets. Methods: According to The Cancer Genome Atlas (TCGA) - LUAD dataset, changes in marker and immune gene activity were analyzed, followed by identification of prognosis-related differential gene sets (DGSs) and their related LUAD subtypes. Survival analysis, correlation with clinical characteristics, and immune microenvironment assessment for subtypes were performed. Moreover, the differentially expressed genes (DEGs) between different subtypes were identified, followed by the construction of a prognostic risk score (RS) model and nomogram model. The tumor mutation burden (TMB) and tumor immune dysfunction and exclusion (TIDE) of different risk groups were compared. Results: Two LUAD subtypes were determined according to the activity changes of the hallmark and immunologic gene sets. Cluster 2 had worse prognosis, more advanced tumor and clinical stages than cluster 1. Moreover, a prognostic RS signature was established using two LUAD subtype-related DEGs, which could stratify patients at different risk levels. Nomogram model incorporated RS and clinical stage exerted good prognostic performance in LUAD patients. A shorter survival time and higher TMB were observed in the high-risk patients. Conclusions: Our findings revealed that our constructed prognostic signature could exactly predict the survival status of LUAD cases, which was helpful in predicting the prognosis and guiding personalized therapeutic strategies for LUAD.

Effect of large volume red blood cell apheresis on cardiovascular functions in healthy donors.

BACKGROUND: Requirements of blood transfusions rise rapidly in China. Improving the efficiency of blood donation could help maintaining sufficient blood supplement. We conducted a pilot research to investigate the reliability and safety of collecting more units of red blood cell by apheresis. METHODS: Thirty-two healthy male volunteers were randomized into two groups: red blood cell apheresis (RA) (n = 16) and whole blood (WB) donation (n = 16). RA group donated individualized RBC volumes by apheresis according to the volunteers' basal total blood volumes and haematocrit levels, WB group donated 400 mL whole blood. All volunteers were scheduled seven visit times in 8 weeks' study period. The cardiovascular functions were assessed by laboratory examinations, echocardiography and cardiopulmonary functional tests. All results were compared between groups at the same visit time and compared between visit 1(before donation) and other visit times within the same group. RESULTS: The average donated RBC volume in RA group and in WB group was 627.25 ± 109.74 mL and 175.28 ± 8.85 mL, respectively(p < 0.05); the RBC, haemoglobin and haematocrit levels changed significantly between times and between groups (p < 0.05). Cardiac biomarker levels such as NT-proBNP, hs-TnT and CK-MB did not change significantly between times or between groups (p > 0.05). The echocardiographic and cardiopulmonary results did not change significantly between times or between groups during the whole study period(p > 0.05). CONCLUSIONS: We provided an efficient and secure method for RBC apheresis. By harvesting more RBC volumes at one single-time, the cardiovascular functions did not change significantly compared with traditional whole blood donation.

G protein inhibitory α subunit 2 is a molecular oncotarget of human glioma.

Identification of novel therapeutic oncotargets for human glioma is extremely important. Here we tested expression, potential functions and underlying mechanisms of G protein inhibitory α subunit 2 (Gαi2) in glioma. Bioinformatics analyses revealed that Gαi2 expression is significantly elevated in human glioma, correlating with poor patients' survival, higher tumor grade and wild-type IDH status. Moreover, increased Gαi2 expression was also in local glioma tissues and different glioma cells. In primary and immortalized (A172) glioma cells, Gαi2 shRNA or knockout (KO, by Cas9-sgRNA) potently suppressed viability, proliferation, and mobility, and induced apoptosis. Ectopic Gαi2 overexpression, using a lentiviral construct, further augmented malignant behaviors in glioma cells. p65 phosphorylation, NFκB activity and expression of NFκB pathway genes were decreased in Gαi2-depleted primary glioma cells, but increased following Gαi2 overexpression. There was an increased binding between Gαi2 promoter and Sp1 (specificity protein 1) transcription factor in glioma tissues and different glioma cells. In primary glioma cells Gαi2 expression was significantly reduced following Sp1 silencing, KO or inhibition. In vivo studies revealed that Gαi2 shRNA-expressing AAV intratumoral injection hindered growth of subcutaneous glioma xenografts in nude mice. Moreover, Gαi2 KO inhibited intracranial glioma xenograft in nude mice. Gαi2 depletion, NFκB inhibition and apoptosis induction were observed in subcutaneous and intracranial glioma xenografts with Gαi2 depletion. Together, overexpressed Gαi2 is important for glioma cell growth possibly by promoting NFκB cascade activation.

Incidences of aortic and mitral valve strands in patients with migraine with aura.

OBJECTIVE: To analyze the potential association between valvular strands and migraine with aura. METHODS: During a 1-year period,transesophageal echocardiography was performed in 51 consecutive patients with migraine with aura and 75 control subjects who underwent transesophageal echocardiography for other purposes and had no history of migraine. The presence of aortic and mitral valve strands was evaluated. RESULTS: The incidence of valvular strands was 21.5% (11/51) in migraine patients and 28.0% (21/75) in control subjects (Χ²=0.663, P=0.416). The incidence of patent foramen ovale was significantly higher in patients with migraine with aura than in control subjects (50.9% vs.29.3%) (Χ²=6.302, P=0.012). The incidence of aortic valve strands was significantly higher than that of mitral valve strands in migraine patients (Χ²=4.320,P=0.038). CONCLUSION: Valvular strands are not associated with migraine with aura and show little clinical significance.