KEAP1 promotes anti-tumor immunity by inhibiting PD-L1 expression in NSCLC.

Immunotherapy has become a prominent first-line cancer treatment strategy. In non-small cell lung cancer (NSCLC), the expression of PD-L1 induces an immuno-suppressive effect to protect cancer cells from immune elimination, which designates PD-L1 as an important target for immunotherapy. However, little is known about the regulation mechanism and the function of PD-L1 in lung cancer. In this study, we have discovered that KEAP1 serves as an E3 ligase to promote PD-L1 ubiquitination and degradation. We found that overexpression of KEAP1 suppressed tumor growth and promoted cytotoxic T-cell activation in vivo. These results indicate the important role of KEAP1 in anti-cancer immunity. Moreover, the combination of elevated KEAP1 expression with anti-PD-L1 immunotherapy resulted in a synergistic effect on both tumor growth and cytotoxic T-cell activation. Additionally, we found that the expressions of KEAP1 and PD-L1 were associated with NSCLC prognosis. In summary, our findings shed light on the mechanism of PD-L1 degradation and how NSCLC immune escape through KEAP1-PD-L1 signaling. Our results also suggest that KEAP1 agonist might be a potential clinical drug to boost anti-tumor immunity and improve immunotherapies in NSCLC.

Small but strong: the emerging role of small nucleolar RNA in cardiovascular diseases.

Cardiovascular diseases (CVDs) are the leading cause of mortality and disability worldwide. Numerous studies have demonstrated that non-coding RNAs (ncRNAs) play a primary role in CVD development. Therefore, studies on the mechanisms of ncRNAs are essential for further efforts to prevent and treat CVDs. Small nucleolar RNAs (snoRNAs) are a novel species of non-conventional ncRNAs that guide post-transcriptional modifications and the subsequent maturation of small nuclear RNA and ribosomal RNA. Evidently, snoRNAs are extensively expressed in human tissues and may regulate different illnesses. Particularly, as the next-generation sequencing techniques have progressed, snoRNAs have been shown to be differentially expressed in CVDs, suggesting that they may play a role in the occurrence and progression of cardiac illnesses. However, the molecular processes and signaling pathways underlying the function of snoRNAs remain unidentified. Therefore, it is of great value to comprehensively investigate the association between snoRNAs and CVDs. The aim of this review was to collate existing literature on the biogenesis, characteristics, and potential regulatory mechanisms of snoRNAs. In particular, we present a scientific update on these snoRNAs and their relevance to CVDs in an effort to cast new light on the functions of snoRNAs in the clinical diagnosis of CVDs.

Study on the molecular mechanism of Rac3 on regulating autophagy in human lung cancer cells

Retraction of: 'Study on the molecular mechanism of Rac3 on regulating autophagy in human lung cancer cells', by Xuyang Xiao, Gebang Wang, Hongxu Liu, JBUON 2017;22(2):445-453; PMID:28534368. Following the publication of the above article, readers drew to our attention that part of the data was unreliable. The authors were requested to provide the raw data to prove the originality, but were unable to do so. After an investigation, the Editors of JBUON decided to retract this article. We thank the readers for bringing this matter to our attention. We apologize for any inconvenience it may cause.

Pectus excavatum requiring temporary pacemaker implantation before Nuss procedure: a case report.

Pectus excavatum is the most common chest wall deformity, and some patients also have it combined with cardiac arrhythmias. It is a rare occurrence for there to be a severe conduction block that requires a temporary pacemaker implantation before the surgical correction. Here we reported a case of pectus excavatum with a second-degree atrial-ventricular (AV) block (Mobitz II) who had temporary pacemaker implantation before the Nuss procedure. The young patient had a chest wall deformity for 6 years and it got worse with age. The Haller index was 4.21, and we evaluated that he should receive the Nuss procedure. An AV block was found during the preoperative electrocardiogram examination; furthermore, Holter monitor proved that he had first-degree AV block and a second-degree AV block (Mobitz II). After consultation with the anesthesiologist and cardiologist, we suggested that a temporary pacemaker placement should be performed under local anesthesia before the minimally invasive operation and removed as soon as the patient revived from general anesthesia. A postoperative Holter monitor was implemented, and the conduction defect disappeared shortly after the operation. However, the Holter monitor showed that the conduction defect was still existed during the follow-up period, which indicated that severe conduction defects should be originated from the conduction system itself, rather than the compression to the heart. The temporary pacemaker was essential to ensure the conducting of the operation went smoothly.

Clinical application of enhanced recovery after surgery (ERAS) in pectus excavatum patients following Nuss procedure.

BACKGROUND: Evaluate the effect of enhanced recovery after surgery (ERAS) protocol on postoperative recovery quality of pectus excavatum patients with Nuss procedure. METHODS: A retrospective study was performed on patients undergoing Nuss procedure from the Department of Thoracic Surgery of The Cancer Hospital of China Medical University between September 2016 and September 2019. Patients were divided into 2 groups by perioperative management: the traditional procedure group (T group) and the ERAS strategy group (E group). The outcome measures were postoperative drainage time, postoperative hospital time, and postoperative complications measured by the Clavien-Dindo method. RESULTS: Of the 168 patients from this time period, 148 met the inclusion criteria (75 in Group T and 73 in Group E). All operations involved in this study were completed successfully. There was no statistical difference between the 2 groups with respect to baseline demographics (P>0.05). In Group E, postoperative drainage time (2.53±0.72 vs. 3.45±2.07 days) and postoperative hospitalization time (4.96±1.48 vs. 7.71±7.78 days) were statistically significantly better than those in Group T (P<0.05). There was no difference in overall postoperative complications as measured by Clavien-Dindo score. CONCLUSIONS: The measures of no indwelling urinary catheter (IDUC), laryngeal mask anesthesia, and indwelling tubule drainage can improve postoperative recovery quality of pectus excavatum patients following Nuss procedure.

LncRNA SBF2-AS1 affects the radiosensitivity of non-small cell lung cancer via modulating microRNA-302a/MBNL3 axis.

Background: Long non-coding RNAs (lncRNAs) have been reported to participate in many diseases including non-small cell lung cancer (NSCLC), thus our objective was to investigate the impact of lncRNA SBF2-AS1 modulating microRNA-302a (miR-302a) expression on radiosensitivity of NSCLC.Methods: The expression of SBF2-AS1, miR-302a and muscleblind-like 3 (MBNL3) in NSCLC tissues of the radiotherapy-sensitive and radiotherapy-resistant groups was tested. The radiosensitivity of parent and resistant strains (NCI-H1299 and NCI-H1299R cells) was detected. Further, cells were treated with si-SBF2-AS1 and miR-302a mimics to determine their roles in proliferation and apoptosis of parent strain and resistant strain cells as well as transfected cells. The in-vivo growth capacity of the cells and the effect of radiotherapy on tumor size of NSCLC were detected.Results: Up-regulated SBF2-AS1 and MBNL3 and down-regulated miR-302a in NSCLC tissues of the radiotherapy resistant group. Overexpression of SBF2-AS1 and MBNL3 and low expression of miR-302a were witnessed in NCI-H1299R cells. Down-regulated SBF2-AS1 or up-regulated miR-302a suppressed the proliferation while boosted the apoptosis of NCI-H1299 cells and decreased the radioresistance of the NCI-H1299R cells. Silencing SBF2-AS1 or up-regulating miR-302a restrained tumor growth in vivo.Conclusion: Our study presents that high expression of miR-302a or inhibition of SBF2-AS1 can enhance the radiosensitivity and apoptosis of NSCLC cells through downregulation of MBNL3, which is a therapeutic target for NSCLC.

Feasibility of nodal classification for non-small cell lung cancer by merging current N categories with the number of involved lymph node stations.

INTRODUCTION: The aim of this study was to assess the prognoses of patients with non-small cell lung cancer (NSCLC) according to the current nodal (N) categories of the tumor, node and metastasis (TNM) classification and the number of involved lymph node stations. METHODS: Five hundred and seventy patients with NSCLC underwent surgery from 1 January 2005 to 31 December 2009 and were analysed retrospectively. Postoperative overall survival was analysed according to two nodal classifications: the current N0, N1, N2 and N3 categories and those based on the number of involved nodal stations: N0, N1a (single N1), N1b (multiple N1), N2a1 (single N2 without N1), N2a2 (single N2 with N1), N2b1 (multiple N2 without N1) and N2b2 (multiple N2 with N1). RESULTS: Five-year survival rates were 76.1%, 53.4% and 26.3% for N0, N1 and N2, respectively (P < 0.001). When survival was analysed by the number of involved nodal stations, the groups with significant differences were maintained; otherwise, they were merged, and new codes were assigned as follows for exploratory analyses: NA (N0), NB (N1a), NC (N1b, N2a (i.e., N2a1 and N2a2) and N2b1) and ND (N2b2). Five-year survival rates were 76.1%, 60.0%, 39.1%, and 11.4% for NA, NB, NC and ND, respectively, and there were significant differences among them. This N classification was an independent prognostic factor in multivariate analyses. CONCLUSION: Pending prospective and international validation, it is practical to merge the current N categories with the number of involved lymph node stations when evaluating the postoperative prognosis of NSCLC patients.

The feasibility and safety of thoracoscopic surgery under epidural and/or local anesthesia for spontaneous pneumothorax: a meta-analysis.

The aim of this study was to compare thoracoscopic surgery for spontaneous pneumothorax under epidural and/or local anesthesia (ELA) with that under general anesthesia and prove the feasibility and safety of thoracoscopic surgery under ELA for spontaneous pneumothorax. Relevant studies were searched in five databases from their date of publication to June 2016. We collected and analyzed the data concerning operative time, hospital stay, complications, air leak, recurrence and perioperative mortality. A forest plot was performed to compare the differences between the two groups. There were no significant differences between the ELA group and the general anesthesia (GA) group in operative time, hospital stay, complications, air leak or recurrence. There were 6 deaths reported in two studies. However, patients in the ELA group had significantly shorter global operating room time. Our study demonstrated that ELA, in comparison with GA, is feasible and safe for thoracoscopic surgery of spontaneous pneumothorax.

Rac3 Regulates Cell Invasion, Migration and EMT in Lung Adenocarcinoma through p38 MAPK Pathway.

Background: The role of Rac3 in cell proliferation in lung adenocarcinoma has been tackled in our previous study. However, the role of Rac3 in cell invasion and migration of lung adenocarcinoma is still not clear. Methods: The expression of Rac3 in lung adenocarcinoma specimens and paired noncancerous normal tissues were evaluated by immunohistochemistry. Lentivirus-mediated RNA interference (RNAi) was employed to silence Rac3 in lung adenocarcinoma cell lines A549 and H1299. A p38 MAPK inhibitor (LY2228820) was employed to inhibit activity of p38 MAPK pathway. Cell invasion and migration in vitro were examined by invasion and migration assays, respectively. PathScan® intracellular signaling array kit and western blot were employed in mechanism investigation. Results: Rac3 expression was frequently higher in lung adenocarcinoma than paired noncancerous normal tissues. Rac3 expression was an independent risk factor for lymphonode metastasis, and was associated with worse survival outcome. Silencing of Rac3 inhibited cell invasion and cell migration in lung adenocarcinoma cell lines. Knockdown of Rac3 decreased activity of p38 MAPK pathway. LY2228820, which was an important p38 MAPK inhibitor, inhibited Rac3-induced cell invasion and migration of lung adenocarcinoma. E-cadherin expression was increased and vimentin expression was decreased after silencing of Rac3 or following the treatment of LY2228820. Conclusions: Our findings suggest that Rac3 regulates cell invasion, migration and EMT via p38 MAPK pathway. Rac3 may be a potential biomarker of invasion and metastasis for lung adenocarcinoma, and knockdown of Rac3 may potentially serve as a promising therapeutic target for lung adenocarcinoma.

Study on the molecular mechanism of Rac3 on regulating autophagy in human lung cancer cells.

PURPOSE: Rac3 plays an important role in regulating tumorigenesis. Autophagy plays a vital role in tumorigenesis and tumor progression. The relationship between the two remains unclear. The objective of the present study was to determine the specific molecular mechanism of intracellular Rac3 in regulating autophagy and reveal the relationship between tumor cell autophagy and apoptosis. METHODS: A laser confocal microscope was used to photograph the accumulated EGFP-MAP1LC3 spots for investigating the relationship between Rac3 and autophagy at the cellular level. Immunoblotting was also used to investigate the relationship between Rac3 and autophagy. The autophagy flux arising from inhibition of Rac3 was detected with autophagy inhibitors and ATG5 and ATG7 siRNA interference experiments. ATF4 and DDIT4 siRNA interference and overexpression experiments were conducted to investigate the relationship between endoplasmic reticulum stress, the MTOR signaling pathway, and autophagy arising from inhibition of Rac3. Co-immunoprecipitation experiments were performed to investigate the interaction between Rac3 and proteins related to endoplasmic reticulum stress. Co-immunoprecipitation was performed to investigate the structural domains between Rac3 and HSPA5. RESULTS: The expression of ATF4 and DDIT4 was upregulated, which inhibited the MTOR signaling pathway and induced autophagy of human non-small cell lung cancer cells after Rac3 siRNA was introduced. The degree of acetylation of the substrate, HSPA5, increased and the endoplasmic reticulum stress response was activated after Rac3 was inhibited. CONCLUSION: In conclusion, the degree of acetylation of HSPA5 increased and it was dissociated from the receptor, EIF2AK3, on the endoplasmic reticulum membrane, thus causing the endoplasmic reticulum stress response. Endoplasmic reticulum stress activated the expression of the ATF4 protein, upregulated the level of DDIT4, inhibited the MTOR signaling pathway, and caused cellular autophagy.

Rac3 regulates cell proliferation through cell cycle pathway and predicts prognosis in lung adenocarcinoma.

Lung cancer is still the leading cause of malignant deaths in the world. It is of great importance to find novel functional genes for the tumorigenesis of lung cancer. We demonstrated that Rac3 could promote cell proliferation and inhibit apoptosis in lung adenocarcinoma cell line A549 previously. The aim of this study was to investigate the function and mechanism of Rac3 in lung adenocarcinoma cell lines. Immunohistochemistry staining was performed in 107 lung adenocarcinoma tissues and matched non-tumor tissues. Multivariate analysis and Kaplan-Meier analysis were used to investigate the correlation between Rac3 expression and the clinical outcomes. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation assay, and flow cytometry analysis were employed to determine the proliferative ability, cell cycle distribution, and apoptosis in H1299 and H1975 cell lines. Gene expression microarray and pathway analysis between the Rac3-siRNA group and the control group in A549 cells were performed to investigate the pathways and mechanism of Rac3 regulation. Rac3 was shown to be positively expressed in lung adenocarcinoma tissues, and the expression of Rac3 associates with longer survival in lung adenocarcinoma patients. Silencing of Rac3 significantly induced cell growth inhibition, colony formation decrease, cell cycle arrest, and apoptosis of lung adenocarcinoma cell lines, which accompanied by obvious downregulation of CCND1, MYC, and TFDP1 of cell cycle pathway involving in the tumorigenesis of lung adenocarcinoma based on the gene expression microarray. In conclusion, these findings suggest that Rac3 has the potential of being a therapeutic target for lung adenocarcinoma.

MicroRNA-570 promotes lung carcinoma proliferation through targeting tumor suppressor KLF9.

Increasing studies have shown that MicroRNAs (miRNAs) play critical roles in the progression of lung carcinoma. In the present study, the expression and functions of miR-570 were investigated. We found that miR-570 was significantly up-regulated in lung cancer tissues, compared with adjacent non-cancerous tissues. In vitro studies further showed that miR-570 mimics could promote, while its antisense oligos inhibit cell proliferation and invasion. At the molecular level, krüppel-like factor 9 (KLF9), a tumor suppressor gene, was identified as a potential target of miR-570 in lung cancer cells. Indeed, miR-570 could negatively regulate protein levels of KLF9 through targeting its 3'-untranslated region. Taken together, our results suggest a previously unknown miR-570/KLF9 molecular network controlling lung carcinoma progression.

Survival of M1a Non-Small Cell Lung Cancer Treated Surgically: A Retrospective Single-Center Study.

BACKGROUND: Stage IV non-small cell lung cancer (NSCLC) is always associated with a poor outcome and is rarely treated with surgical resection. The aim of this study was to retrospectively analyze the effectiveness of surgical treatments. METHODS: We have retrospectively analyzed the records of NSCLC patients with local thoracic metastatic disease (M1a) who had been treated with surgical resection. The impact on survival of eight variables (age, gender, smoking status, current drinking status, site of metastasis, pathology classifications, resection status, and presence of adjuvant treatment) were further assessed. RESULTS: Eighty patients (49 males, 61%) with a median age of 58 (range, 38-80) were included. Metastatic sites included: pleural nodules with or without effusion metastasis (51, 63.8%), pleural effusion without nodules (7, 8.8%), contralateral lung (9, 11.3%), diaphragm nodules metastasis (5, 6.3%), and pericardium nodules metastasis (8, 10%). Histology was adenocarcinoma in 55, squamous-cell carcinoma in 16, large cell in 5 and other in 4 patients. Types of lung resection performed for primary tumors were complete resection in 43 and limited resection in 37 patients. Survival at 5 years for the overall population reached 31% (95% confidence interval, 19.4-43%). The median overall survival time was 34.3 months. Ten (12.5%) patients survived for more than 5 years. Smoking status and postoperative adjuvant treatment were independent prognostic factors (p = 0.006 and 0.013). There was no impact on survival for the other six variables. CONCLUSION: Surgical treatments in M1a NSCLC seem to be associated with improved survival than published results and might be considered in the management of selected cases. Selected patients, including good performance status and nonsmoking histology, may predict for improved survival in these patients.

Silencing of Rac3 inhibits proliferation and induces apoptosis of human lung cancer cells.

BACKGROUND: Rac3, a member of the Rac family of small guanosine triphosphatases (GTPases), regulates a variety of cell functions, including the organization of the cytoskeleton, cell migration, and invasion. Overexpression of Rac3 has been reported in several human cancers. However, the role of Rac3 in lung cancer (LC) has not been determined in detail. The purpose of this study was to investigate the effect of silencing of Rac3 expression in human LC cells and the consequences for cell survival. MATERIALS AND METHODS: Lentivirus small hairpin RNA (shRNA) interference techniques were utilized to knock down the Rac3 gene. Gene and protein expression was quantified by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. LC cell apoptosis was examined by annexin V-APC /propidium iodide staining. RESULTS: Efficient silencing of Rac3 strongly inhibited A549 cell proliferation and colony formation ability, and significantly decreased tumor growth. Moreover, flow cytometry analysis showed that knockdown of Rac3 led to G2/M phase cell cycle arrest as well as an excess accumulation of cells in the G1 and S phase. CONCLUSIONS: Thus, functional analysis using shRNAs revealed a critical role for Rac3 in the tumor growth of LC cells. shRNA silencing of Rac3 could provide an effective strategy to treat LC.