HBB as a Novel Biomarker for the Diagnosis and Monitoring of Lung Cancer Regulates Cell Proliferation via ERK1/2 Pathway.

Objective: Recent studies have revealed that hemoglobin beta (HBB) plays an important role not only in blood disorders but also in malignancies. The aim of this study is to investigate the clinical significance, diagnostic value, and biological function of HBB in lung cancer. Methods: HBB expression was examined in lung cancer tissues and plasma samples using quantitative real-time polymerase chain reaction, and its relationship with clinical pathological characteristics was analyzed. Receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic value of HBB in lung cancer. The proliferation of A549 and SPCA1 cells was analyzed using a cell counting kit-8 assay and protein expressions were detected by western blot. Results: The expressions of HBB were found to be down-regulated in both lung cancer tissues and plasma samples. Notably, plasma HBB levels were significantly elevated in postoperative samples when compared to their preoperative counterparts. Across 66 cases of lung cancer tissues, a correlation was observed between HBB levels and both gender and tumor, node, metastasis staging. ROC curve analysis further confirmed the high diagnostic potential of HBB expression in lung cancer. Moreover, the combination of HBB and carcinoembryonic antigen (CEA) had greater significance than HBB or CEA alone in the diagnosis of lung cancer. Knocking out or overexpressing HBB could affect lung cancer cell proliferation through the ERK1/2 signaling pathway. Conclusion: HBB can serve as a novel biomarker for the diagnosis and monitoring of lung cancer, regulating cell proliferation via the ERK1/2 pathway and playing a pivotal role in the oncogenesis and progression of the disease.

CYTOR Promotes Proliferation of Lung Cancer Cell by Targeting miR-103a-3p to Upregulate HMGB1.

Lung cancer is one of the most dangerous malignant tumors to human health in the world. Previous researches have shown that cytoskeleton regulator RNA (CYTOR), a long noncoding RNA was involved in the occurrence and development of various types of cancer. The aim of this study is to investigate the clinical significance and biological function of CYTOR in lung cancer. Real-time quantitative PCR was applied to detect the expression of CYTOR. The proliferation of A549 and H1299 cells was analyzed by CCK8 assay. The luciferase reporter assay and RNA pull-down assay were used to reveal the interactions between CYTOR and its downstream targets. Western blot was used to detect the expression of high-mobility group protein B1 (HMGB1). Here we found CYTOR was upregulated in lung cancer tissues and cell lines. The proliferation of A549 and H1299 cells was inhibited after CYTOR silencing. In addition, CYTOR could directly interact with and negatively regulate miR-103a-3p, and miR-103a-3p inhibited cell proliferation by targeting HMGB1. The CYTOR/miR-103a-3p/HMGB1 axis promoted lung cancer cell proliferation. CYTOR sponges miR-103a-3p to promote the proliferation of lung cancer cells through HMGB1. The CYTOR/miR-103a-3p/HMGB1 axis plays a critical role in the progression of lung cancer.

LIM-domain binding protein 2 was down-regulated by miRNA-96-5p inhibited the proliferation, invasion and metastasis of lung cancer H1299 cells.

OBJECTIVES: Lung cancer was one of the most common malignancies around the world. It has great significance in to search for the mechanism of occurrence and development of lung cancer. LIM Domain Binding protein 2 (LDB2) belongs to the LIM-domain binding family, it can be used as a binding protein that combined with other transcription factors to form the transcription complex for regulating the expression of target genes. The expression of microRNA-96-5p (miR-96-5p) has been investigated in various tumors. The aim of this study is to investigate the potential role of LDB2 and miR-96-5p in lung cancer. METHODS: Real-time quantitative PCR was applied to detect the expression of LDB2 and miR-96-5p. The proliferation, invasion, and metastasis of H1299 cells were analyzed by CCK8, transwell, and wound healing assay after LDB2 or miR-96-5p transfection. Luciferase activities assay and western blot were used to reveal the targeted regulation between LDB2 and miR-96-5p. RESULTS: Here the authors found LDB2 was down-regulated in lung cancer tissues and negatively correlated with miR-96-5p expression, it could promote or inhibit the proliferation, invasion and metastasis of H1299 cells after LDB2 knockdown or overexpression and regulate the expression of cyclinD1, MMP9, Bcl-2, and Bax via ERK1/2 signaling pathway. Furthermore, miR-96-5p exerted its function by directly binding to 3'-UTR of LDB2 and regulating expression of LDB2. miR-96-5p could promote the proliferation, invasion, and metastasis of H1299 cells. CONCLUSION: These findings demonstrate that LDB2 can act as a new regulator to inhibit cell proliferation, invasion, and metastasis via the ERK1/2 signaling pathway, and miR-96-5p may be a potential promising molecular by targeting LDB2 in lung cancer.

LIM-domain binding protein 2 was down-regulated by miRNA-96-5p inhibited the proliferation, invasion and metastasis of lung cancer H1299 cells

Abstract Objectives: Lung cancer was one of the most common malignancies around the world. It has great significance in to search for the mechanism of occurrence and development of lung cancer. LIM Domain Binding protein 2 (LDB2) belongs to the LIM-domain binding family, it can be used as a binding protein that combined with other transcription factors to form the transcription complex for regulating the expression of target genes. The expression of microRNA-96-5p (miR-96-5p) has been investigated in various tumors. The aim of this study is to investigate the potential role of LDB2 and miR-96-5p in lung cancer. Methods: Real-time quantitative PCR was applied to detect the expression of LDB2 and miR-96-5p. The proliferation, invasion, and metastasis of H1299 cells were analyzed by CCK8, transwell, and wound healing assay after LDB2 or miR-96-5p transfection. Luciferase activities assay and western blot were used to reveal the targeted regulation between LDB2 and miR-96-5p. Results: Here the authors found LDB2 was down-regulated in lung cancer tissues and negatively correlated with miR-96-5p expression, it could promote or inhibit the proliferation, invasion and metastasis of H1299 cells after LDB2 knockdown or overexpression and regulate the expression of cyclinD1, MMP9, Bcl-2, and Bax via ERK1/2 signaling pathway. Furthermore, miR-96-5p exerted its function by directly binding to 3′-UTR of LDB2 and regulating expression of LDB2. miR-96-5p could promote the proliferation, invasion, and metastasis of H1299 cells. Conclusion: These findings demonstrate that LDB2 can act as a new regulator to inhibit cell proliferation, invasion, and metastasis via the ERK1/2 signaling pathway, and miR-96-5p may be a potential promising molecular by targeting LDB2 in lung cancer.

Lupus-associated atypical memory B cells are mTORC1-hyperactivated and functionally dysregulated.

OBJECTIVES: A population of atypical memory B cells (AtMs) are greatly expanded in patients with active lupus, but their generation and pathophysiological roles are poorly defined. The aim of this study was to comprehensively characterise lupus AtMs with a purpose to identify therapeutic clues to target this B cell population in lupus. METHODS: Peripheral B cell subsets were measured by flow cytometry. Sorting-purified B cell subsets were subject to RNA sequencing and functional studies. Plasma cytokines and secreted immunoglobulins were detected by Luminex or ELISA. In situ renal B cells were detected by multiplexed immunohistochemistry. RESULTS: CD24-CD20hi AtMs were strongly increased in two Chinese cohorts of patients with treatment-naïve lupus. Gene expression profile indicated that B cell signalling and activation, lipid/saccharide metabolism and endocytosis pathways were abnormally upregulated in lupus AtMs. In addition, the mammalian target of rapamycin complex 1 (mTORC1) pathway was remarkably activated in lupus AtMs, and blocking mTORC1 signalling by rapamycin abolished the generation of T-bet+ B cells and terminal differentiation of lupus AtMs. Furthermore, lupus AtMs displayed a dysfunctional phenotype, underwent accelerated apoptosis, poorly co-stimulated T cells and produced proinflammatory cytokines. Interestingly, lupus AtMs were in a paradoxically differentiated status with markers pro and against terminal differentiation and enriched with antinucleosome reactivity. Finally, AtMs were accumulated in the kidneys of patients with lupus nephritis and associated with disease severity. CONCLUSIONS: These findings demonstrated that mTORC1-overactivated lupus AtMs are abnormally differentiated with metabolic and functional dysregulations. Inhibiting mTORC1 signalling might be an attractive option to target AtMs and to improve therapeutic effectiveness in patients with lupus.

MAPK/c-Jun signaling pathway contributes to the upregulation of the anti-apoptotic proteins Bcl-2 and Bcl-xL induced by Epstein-Barr virus-encoded BARF1 in gastric carcinoma cells.

BARF1, encoded by Epstein-Barr virus (EBV), has been hypothesized to function as an oncogene, which was expressed in gastric carcinoma cells. Additionally, it has been reported that the anti-apoptotic function is closely associated with the expression of the B-cell lymphoma-2 (Bcl-2) protein. In addition, the signaling pathway has been reported to be involved in numerous diseases, including the mitogen-activated protein kinase (MAPK) cascade. In order to study the specific mechanism of anti-apoptotic function, BARF1-stably-expressing immortalized normal human embryo gastric epithelial cell line GES1 (GES-BARF1), and well-, moderately- and poorly-differentiated gastric carcinoma cell lines, MKN28 (which has been reported to be contaminated with the moderately-differentiated MKN74 gastric carcinoma cell line), SGC7901 and BGC823 (MKN-BARF1, SGC-BARF1 and BGC-BARF1, respectively) (GCC-BARF1) were constructed, with transfection of cells with the empty vector pSG5 acting as controls. Western blot analysis was performed to analyze the protein expression and the phosphorylation levels. Compared with the controls, it was found that the protein expression levels of c-Jun, Bcl-2 and B-cell lymphoma-extra large (Bcl-xL), as well as the phosphorylation levels of c-Jun, c-Jun N-terminal kinase (JNK) 1/2/3, p38 and extracellular signal-regulated kinase (ERK) 1/2 proteins were upregulated in 3 GCC-BARF1 but not significantly changed in GES-BARF1. The expression levels of the c-Jun, Bcl-2 and Bcl-xL proteins, and levels of c-Jun protein phosphorylation were significantly decreased in SGC-BARF1 cells subsequent to treatment with SP600125, SB203580, and U0126, which were the specific inhibitors of JNK1/2/3, p38 and ERK1/2 respectively. In addition, there was a gradual increase in the protein expression and phosphorylation levels between normal gastric epithelial cells, and well-differentiated, moderately-differentiated and poorly-differentiated gastric carcinoma cells, but this was not statistically significant. Therefore, the present study hypothesized that JNK1/2/3-, p38- and ERK1/2-MAPK/c-Jun cascade signaling pathways may contribute to the upregulation of the expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL induced by BARF1 in gastric carcinoma cells. This mechanism may mainly work in the progressive phase of the development in EBV-associated gastric carcinoma.