ABSTRACT
Cation-free zirconosilicate zeolite CHA and thin zirconia-supported membranes were in situ synthesized in a fluoride-free gel for the first time. The usage of the ZrO2/Al2O3 composite support inhibited the transportation of aluminum from the support into zeolite membranes. No fluorite source was used for the synthesis of cation-free zeolite CHA membranes, indicating the green property of the synthesis. The thickness of the membrane was only 1.0 µm. The best cation-free zeolite CHA membrane prepared by the green in situ synthesis displayed a high CO2 permeance of 1.1 × 10-6 mol/(m2 s Pa) and CO2/CH4 selectivity of 79 at 298 K and 0.2 MPa pressure drop for an equimolar CO2/CH4 mixture.
ABSTRACT
Brain metastasis is a severe complication that affects the survival of lung cancer patients. However, the mechanism of brain metastasis in lung cancer remains unclear. In this study, we constructed an in vitro BBB model and found that cells from the high-metastatic nonsmall cell lung cancer (NSCLC) cell line H1299 showed a higher capacity to pass through the blood-brain barrier (BBB), as verified by Transwell assays, than cells from the low-metastatic NSCLC cell line A549. Brain microvascular endothelial cells (BMECs) could internalize H1299-derived exosomes, which remarkably promoted A549 cells across the BBB. The BBB-associated exosomal long noncoding RNA (lncRNA) was selected from the RNA-Seq dataset (GSE126548) and verified by real-time PCR and Transwell assays. LncRNA LINC01356 was significantly upregulated in H1299 cells and exosomes derived from these cells compared to that of A549 cells. Moreover, LINC01356 was also upregulated in serum exosomes of patients with NSCLC with brain metastasis compared with those without metastasis. In addition, BMECs treated with LINC01356-deprived exosomes expressed higher junction proteins than those treated with the control exosomes, and silencing LINC01356 in exosomes derived from H1299 cells could inhibit A549 cells from crossing the BBB. These data might indicate that the exosomal lncRNA LINC01356 derived from brain metastatic NSCLC cells plays a key role in remodeling the BBB system, thereby participating in brain metastasis in lung cancer.
ABSTRACT
Glioblastoma (GBM) is a kind of malignant primary brain tumor, which is difficult to cure. Continuous researches have underlined that long non-coding RNAs (lncRNAs) get widely involved in the occurrence and progression of tumors, and glioblastoma is included. In this paper, we identified lncRNA PITPNA antisense RNA 1 (PITPNA-AS1) and explored its in-depth regulatory mechanism in glioblastoma cells. Firstly, RT-qPCR examined that PITPNA-AS1 was highly expressed in glioblastoma. Then, PITPNA-AS1 role in glioblastoma was assessed via functional assays. The results demonstrated that depletion of PITPNA-AS1 inhibited the proliferation and promoted the apoptosis of glioblastoma cells. After confirming that PITPNA-AS1 mainly existed in cell cytoplasm, we conducted mechanism assays which disclosed that PITPNA-AS1 sequestered microRNA-223-3p (miR-223-3p) and modulated epidermal growth factor receptor (EGFR) expression, thereby participating in the activation of PI3K/AKT signaling pathway. Eventually, rescue assays validated PITPNA-AS1 sponged miR-223-3p to promote EGFR expression, thus activating PI3K/AKT signaling pathway to accelerate proliferation and inhibit apoptosis of GBM cells. Overall, PITPNA-AS1 played an oncogenic role in glioblastoma which might be developed as a potential biomarker for glioblastoma diagnosis and treatment in the future.[Figure: see text].