Improvement of average magnetic field measurement based on magnetic-field-sensitive Ramsey fringes.

Accurate magnetic field measurement is the key to evaluating the second-order Zeeman effect. The conventional method is to deduce the magnetic field by determining the center frequency of the magnetic-field-sensitive Ramsey fringes. In this Letter, we present a more rigorous theory for this method and demonstrate that the current peak-searching method has a non-negligible sub-Hz or even larger deviation. We introduce an improved method that considers more parameters and a strict formula that can correct the deviation and suppress it to below 0.1 Hz. Corresponding experiments on the 85Rb atomic fountain demonstrate that this improved method is expected to enhance the precision of magnetic field measurement and improve the atomic fountain clock.

Predictive value of tumor mutational burden for immunotherapy in non-small cell lung cancer: A systematic review and meta-analysis.

BACKGROUND: Immunotherapy has emerged as a promising treatment for non-small cell lung cancer (NSCLC). Yet, some patients cannot benefit from immunotherapy, and reliable biomarkers for selecting sensitive patients are needed. Herein, we performed a meta-analysis to evaluate the predictive value of tumor mutational burden (TMB) in NSCLC patients treated with immunotherapy. METHODS: Eligible studies were comprehensively searched from electronic databases prior to August 31, 2021. Meta-analyses of high TMB versus low TMB as well as immunotherapy versus chemotherapy in patients with high/low TMB were conducted. Hazard ratio (HR) with corresponding 95% confidence interval (95%CI) for progression-free survival (PFS) and overall survival (OS) and odds ratio (OR) with 95%CI for objective response rate (ORR) were calculated. RESULTS: A total of 31 datasets (3437 patients) and 6 randomized controlled trials (3662 patients) were available for meta-analyses of high TMB versus low TMB and immunotherapy versus chemotherapy, respectively. High TMB predicted significantly favorable PFS (HR = 0.54, 95%CI: 0.46-0.63, P<0.001) and OS (HR = 0.70, 95%CI: 0.57-0.87, P = 0.001), and higher ORR (OR = 3.14, 95%CI: 2.28-4.34, P<0.001) compared with low TMB. In patients with high TMB, immunotherapy was associated with improved PFS (HR = 0.62, 95%CI: 0.53-0.72), OS (HR = 0.67, 95%CI: 0.57-0.79) and ORR (OR = 2.35, 95%CI: 1.74-3.18) when compared with chemotherapy. However, in patients with low TMB, immunotherapy seemed to predict inferior PFS (HR = 1.20, 95%CI: 1.02-1.41) and ORR (OR = 0.61, 95%CI: 0.44-0.84) and have no OS benefit (HR = 0.88, 95%CI: 0.74-1.05) as compared with chemotherapy. CONCLUSION: This meta-analysis demonstrates more clinical benefits concerning treatment response and survival outcomes in high-TMB NSCLC patients who are treated with immunotherapy. TMB is a promising biomarker for discriminating NSCLC patients who can benefit more from immunotherapy.

MiR-563 restrains cell proliferation via targeting LIN28B in human lung cancer.

BACKGROUND: Previous investigations have revealed that miR-563 is associated with a number of diseases including the ossification of posterior longitudinal ligament, Parkinson's disease or drug resistance to leukemia. Yet, the role of miR-563 and its molecular mechanism in the initiation and progression of cancers has not been previously explored. In this study, we aimed to provide clues to the function of miR-563 and its direct target in lung cancer. METHODS: Online informatics software was applied to predict the target genes of miR-563. MiR-563 targeting LIN28B was evaluated through the luciferase reporter gene analysis. The effect of miR-563 on LIN28B at the level of RNA and protein was detected using RT-PCR and immunoblotting. The ability of proliferation of human lung cancer A549 was examined by MTT assay. RNA interference targeting LIN28B was examined through immunoblotting. The level of miR-563 and LIN28B and their correlation were analyzed in 27 cases of lung tumor tissues by real-time PCR. RESULTS: Oncogenic LIN28B was identified as one of the target genes of miR-563 in lung cancer cells. MiR-563 dose-dependently decreased the LIN28B RNA level and subsequently its protein level in the cells. Cell proliferation was suppressed by ectopic miR-563 expression and was accelerated after endogenous miR-563 was knocked down by its inhibitor. However, silence in LIN28B reversed promotion of cell proliferation by the inhibition of miR-563. In lung cancer tissues, miR-563 was decreased and negative correlation of miR-563 and LIN28B was shown. CONCLUSION: MiR-563 plays a tumor suppressive role in lung cancer progression via targeting oncogenic LIN28B.

Identification of a Novel BRAF Thr599dup Mutation in Lung Adenocarcinoma.

BRAF mutations are known as oncogenic drivers of non-small cell lung cancer (NSCLC). BRAF inhibition has demonstrated anti-tumor activity in patients with BRAF V600E mutant NSCLC. Further molecular screening for novel BRAF thr599dup mutation is warranted. The novel BRAF Thr599dup gene mutation, for which the repeat amino acid-tyrosine is inserted between the 599th amino acid and the 600th amino acid in exon 15 of BRAF, was identified by next-generation sequencing (NGS) during routine clinical care in a lung carcinoma sample from an Asian never-smoker. Other putative driver alterations including EGFR, ALK were not found in that patient. BRAF Thr599dup gene mutation analysis was consistent with BRAF v600E gene mutation. Here we report a novel BRAF gene mutation with molecular characteristics consistent with those in BRAF-driven NSCLC. Our case expands the scope of BRAF gene mutations and provides broader molecular profiling for optimizing therapeutic options for patients with NSCLC. The new BRAF gene mutation has important clinical meaning for cancer patients.

Identification of a novel KIF13A-RET fusion in lung adenocarcinoma by next-generation sequencing.

OBJECTIVES: RET fusions have been reported in 1-2% of lung adenocarcinomas, and represent an actionable target. Patients whose tumors possess RET fusion are associated with clinical benefit from the treatment with multi-kinase inhibitors such as cabozantinib and vandetanib. Further molecular screening for RET fusions is warranted. Novel KIF13A-RET fusion containing an intact RET kinase domain involving exons 1-18 of KIF13A and exons 12-20 of RET was identified in a lung cancer specimen from an 74-year-old Asian never smoker by next-generation sequencing (NGS) during clinical care. The patient was negative for EGFR, ALK, ROS1 and other putative driver alterations. Fusion analysis is consistent with other described RET fusions and is predicted to result in aberrant constitutive activation caused by dimerization and sensitivity to RET-directed therapies. We describe a novel RET-fusion with molecular characteristics consistent with RET-driven non-small cell lung cancer. Our case expands the spectrum of RET fusion partners and supports broad molecular profiling in non-small cell lung cancer optimizing patient therapeutic options. The new RET fusion has immediate clinical implications for cancer patients.

MicroRNA-4458 suppresses the proliferation of human lung cancer cells in vitro by directly targeting Lin28B.

Previous studies have shown that the expression of microRNA-4458 (miR-4458) is dysregulated in hepatocellular carcinoma and colon cancer. In this study, we investigated the direct target of miR-4458 and its biological functions in human lung cancer cells. By using the database TargetScan, we identified Lin28B, an oncogene, as a direct target gene of miR-4458. In dual-luciferase reporter assay, we found that miR-4458 mimics dose-dependently inhibited the luciferase activity of the wild-type 3'UTR of Lin28B in human lung cancer A549 and NCI-H1299 cell lines without affecting its mutant forms, whereas anti-miR-4458, an inhibitor of miR-4458, dose-dependently promoted the luciferase activity of the wild-type 3'UTR of Lin28B in A549 and NCI-H1299 cell lines without affecting its mutant forms. Overexpression of miR-4458 significantly decreased the protein levels of Lin28B in the cells, and inhibited the cell growth and colony formation. Conversely, knockdown of miR-4458 with anti-miR-4458 significantly increased the protein levels of Lin28B, and promoted the cell proliferation, which could be reverted by knockdown of Lin28B expression. In addition, we detected the expression of Lin28B using RT-PCR in 40 human lung cancer tissues and matched peritumoral tissues, and found that Lin28B was overexpressed in lung cancer tissues and negatively correlated with miR-4458 expression (r=-0.694, P<0.05). We conclude that miR-4458 is a tumor suppressor, and Lin28B is the direct target of miR-4458. These results suggest the modulation of miR-4458/Lin28B expression offers a potential therapeutic strategy for lung cancer.

Hypermethylation of miRNA-589 promoter leads to upregulation of HDAC5 which promotes malignancy in non-small cell lung cancer.

Histone deacetylases (HDACs) are crucial for regulating chromatin activity, which plays a critical role in cell proliferation, differentiation, and apoptosis of various cancers. Therefore, HDAC inhibitors have been applied as effective therapeutic agents for cancer treatment. However, the expression profiles and regulatory mechanisms of histone deacetylases in lung cancer are not well understood. In the present study, aberrant high levels of HDAC5 were observed in non-small cell lung cancer (NSCLC) and further analysis indicated a negative relationship between HDAC5 and a tumor suppressor, miR­589­5p, in NSCLC specimens. Consistently, miR­589­5p reduced the expression of HDAC5 by targeting the 3'UTR of HDAC5 mRNA in NSCLC cells. Considering the loss of miR­589­5p in NSCLC, the methylation status of the miR-589 gene promoter was examined. The hypermethylation of the miR-589 gene promoter was more significant in NSCLC cells compared with lung epithelial cells, and methylation inhibition by 5-aza-2-deoxycytidine (5-Aza-dC) decreased HDAC5 expression. Furthermore, several downstream gene clusters of HDAC5 were studied in the present investigation. As a result, miR­589­5p/HDAC5 pathway was found to regulate a number of cell cycle and epithelial-mesenchymal transition (EMT)-related genes in NSCLC cells. In vitro and in vivo phenotype experiments revealed a critical role of miR­589­5p/HDAC5 pathway in the migration, invasion, and tumorigenicity of NSCLC cells. These findings demonstrate a novel mechanism for deregulation of HDAC5 in NSCLC and suggest that miR­589­5p/HDAC5 pathway may represent a new prognostic biomarker and therapeutic target against NSCLC.

The long non-coding RNA maternally expressed gene 3 activates p53 and is downregulated in esophageal squamous cell cancer.

Esophageal squamous cell cancer (ESCC) is an aggressive malignancy with poor survival. Long non-coding RNAs (lncRNAs) play important roles in tumorigenesis and cancer progression; hence, lncRNAs are also involved in the development and progression of ESCC. In this study, we used quantitative real-time polymerase chain reaction (qRT-PCR) to investigate expression of lncRNA, maternally expressed gene 3 (MEG3) in ESCC. Ectopic expression of MEG3 was performed in ESCC cell lines. Proliferation and apoptosis of ESCC cell lines were analyzed after ectopic expression of MEG3. We found MEG3 was significantly downregulated in ESCC tissues compared with normal tissues by qRT-PCR. Low expression of MEG3 was correlated with lymph node metastasis and advanced TNM stages of ESCC patients and indicated shorter survival (HR = 0.471, 95 % CI 0.234-0.950, P = 0.035), which was confirmed by The Cancer Genome Atlas (TCGA) esophageal cancer dataset. DNA-demethylating agent (5-aza-2-deoxy-cytidine (5-aza-CdR)) treatment significantly increased MEG3 expression level in ESCC cells, and TCGA esophageal cancer dataset also showed that DNA methylation of MEG3 predicted survival. Ectopic expression of MEG3 in ESCC cells inhibited cell proliferation, promoted apoptosis, and suppressed metastasis. Further investigation showed enforced expression of MEG3 activated p53 and its target genes by downregulation of mouse double minute 2 homolog (MDM2). Overall, our study indicated that MEG3 expression loss is common in ESCC and MEG3 could activate p53 and predict prognosis in ESCC.

The single chest tube versus double chest tube application after pulmonary lobectomy: A systematic review and meta-analysis.

OBJECTIVE: Draining of the chest cavity with two chest tubes after pulmonary lobectomy is a common practice. The objective of this study was to evaluate whether using two tubes after a pulmonary lobectomy is more effective than using a single tube. PATIENTS AND METHODS: We performed a meta-analysis of five randomized studies that compared the single chest tube with double chest tube application after pulmonary lobectomy. The primary end-point was amount of drainage and duration of chest tube drainage. The secondary end-points were the patient's numbers of new drain insertion after operation, hospital stay after operation, the patient's numbers of subcutaneous emphysema after operation, the patient's numbers of residual pleural air space, pain score, the number of patients who need thoracentesis, and cost. RESULTS: Five randomized controlled trials totaling 502 patients were included. Meta-analysis results are as follows: There were statistically significant differences in amount of drainage (risk ratio [RR] = -0.15; 95% confidence interval [CI] = -3.17, -0.12, P = 0. 03), duration of chest tube drainage (RR = -0.43; 95% CI = -0.57, -0.19, P = 0.02), pain score (P < 0.05). Compared with patients receiving the double chest tube group, there were no statistically significant differences between the two groups with regard to the patient's numbers of new drain insertion after operation. CONCLUSION: Compared with the double chest tube, the single chest tube significantly decreases amount of drainage, duration of chest tube drainage, pain score, the number of patients who need thoracentesis, and cost. Although there is convincing evidence to confirm the results mentioned herein, they still need to be confirmed by large-sample, multicenter, randomized, controlled trials.