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Autophagy is a highly conserved self-digestion process to promote cell survival in response to nutrient starvation and other metabolic stresses in eukaryotic cells. Dysregulation of this system is linked with numerous human diseases, including cancers. ATG4B, a cysteine protease required for autophagy, cleaves the C-terminal amino acid of ATG8 family proteins to reveal a C-terminal glycine which is necessary for ATG8 proteins conjugation to phosphatidylethanolamine (PE) and insertion to autophagosome precursor membranes. However, the mechanism governing the protein stability of ATG4B in human cancer cells is not fully understood. In this study, tandem affinity purification/mass spectrometry (TAP/MS) were applied to the investigation of the interaction between ATG4B and potential candidate proteins. Then, co-immunoprecipitation (Co-IP) and GST-pull down assays indicated that the candidate protein-SLC27A4 directly interacts with ATG4B in lung cancer cell lines. Intriguingly, we also found that ATG4B protein expression was increased in parallel with SLC27A4 in lung cancer cell lines as well as lung tumor tissues. However, relevant functional research of SLC27A4 in autophagy or oncotherapy has not been investigated before. In this study, we hypothesized that SLC27A4 might act as a mediator of ATG4B, in some respects, through the protein binding directly. Further, we found that the high expression level of SLC7A4 increased the ATG4B stability and was conducive to rapid reaction to everolimus (RAD001)-induced autophagy in human lung cancer cells. As expected, the results showed that SLC27A4 could help to maintain the protein stability and intracellular concentration of ATG4B, thereby triggering rapid autophagy through releasing ATG4B to cytoplasm under conditions of reduced nutrient availability or during stress of chemotherapy in lung cancer cells. Reduced SLC27A4 by si-RNA also showed the enhanced therapeutic efficiency of everolimus, doxorubicin, and cisplatin in human lung cancer cell lines. Collectively, this study may help researchers better understand the mechanism of autophagy vitality in human cancers and SLC27A4/ATG4B complex might act as a new potential therapeutic target of lung tumor chemotherapy.

FUS1 is one of the most important tumor suppressor genes in lung cancer, as well as an important immunomodulatory molecule. Interleukin (IL)-12 has attracted considerable interest as a potential anti-tumor cytokine. Cationic liposome has been shown to effectively deliver therapeutic genes to the lungs and control metastatic lung tumors when administered intravenously. Here we evaluated the enhanced efficacy of cationic liposome-mediated delivery of FUS1 and human IL (hIL)-12 eukaryotic coexpression plasmid (pVITRO2-FUS1-hIL-12) against the human lung cancer in HuPBL-NOD/SCID mice model by local and systemic administration, and explored the related molecular mechanism. Our study demonstrated that FUS1-hIL-12 coexpression could more sufficiently inhibit tumor growth and experimental lung metastasis, significantly prolong the survival of experimental lung metastasis mice. Moreover, FUS1-hIL-12 coexpression performed higher antitumor activity and lower toxicity in the inhibition of experimental lung metastatic tumor compared to cisplatin. We further identified that FUS1-hIL-12 coexpression could induce strong antitumor immune response by secreting much higher levels of human interferon-γ (hIFN-γ) and hIL-15, enhancing expression of MHC-I and Fas, increasing infiltration of activated human CD4+ and CD8+ T lymphocytes. FUS1-hIL-12 coexpression could also obviously induce tumor cell apoptosis and inhibit tumor cell proliferation partly by higher activation of STAT1 signal pathway and upregulation of p53. In addition, FUS1-hIL-12 coexpression also superiorly reduced the angiogenesis in tumors, which might be associated with downregulation of VEGF and VEGFR, and upregulation of human IP-10. Our results therefore suggest that cationic liposome-mediated FUS1-hIL-12 coexpression may be a new promising strategy for lung cancer treatment in clinical studies.

Several 1,4,7,10-tetraazacyclododecane (cyclen)-based linear ( 3a – c ) and cross-linked ( 8a – d ) polymers containing biodegradable ester or disulfide bonds were described. These polymeric compounds were prepared by ring-opening polymerization from various diol glycidyl ethers. The molecular weights of the title polymers were measured by GPC. Agarose gel retardation assays showed that these compounds have good DNA-binding ability and can completely retard plasmid DNA (pDNA) at weight ratio of 20 for linear polymers and 1.2 for cross-linked polymers. The degradation of these polymers was confirmed by GPC. The formed polyplexes have appropriate sizes around 400 nm and zeta-potential values about 15–40 mV. The cytotoxicities of 8 assayed by MTT are much lower than that of 25 KDa PEI. In vitro transfection toward A549 and 293 cells showed that the transfection efficiency (TE) of 8c -DNA polyplex is close to that of 25 kDa PEI at 8c /DNA weight ratio of 4. Structure–activity relationships (SAR) of these linear and cross-linked polymers were discussed in their DNA-binding, cytotoxicity, and transfection studies. In addition, in the presence of serum, the TE of 8 /DNA polyplexes could be improved by introducing chloroquine or Ca 2+ to pretreated cells.

Platinum-based chemotherapies have long been used as a standard treatment in non-small cell lung cancer (NSCLC). However, cisplatin resistance is a major problem that restricts the use of cisplatin. Lung cancer stem cells (LCSCs) represent a subpopulation that is responsible for chemo-resistance. We aim to investigate the biological function of SLC27A2 and its underlying mechanisms in regulating chemo-resistance to cisplatin in LCSCs. Here, our findings testified that CD166

A novel paradigm in tumor biology suggests that non-small cell lung cancer (NSCLC) metastasis is driven by lung cancer stem cell-like cells (LCSCs), but the underlying mechanisms remain unclear. Here, we aim to investigate biological function of CD44 in regulating metastatic trait of LCSCs and its underlying mechanisms. In this study, we found that CD133

Low molecular weight heparin (LMWH) improving the cancer survival has been attracting attention for many years. Our previous study found that LMWH (Fraxiparine) strongly downregulated the invasive, migratory, and adhesive ability of human lung adenocarcinoma A549 cells. Here, we aimed to further identify the antitumor effects and possible mechanisms of Fraxiparine on A549 cells and human highly metastatic lung cancer 95D cells. The ability of cell invasion, migration, and adhesion were measured by Transwell, Millicell, and MTT assays. FITC-labeled phalloidin was used to detect F-actin bundles in cells. Chemotactic migration was analyzed in a modified Transwell assay. Measurement of protein expression and phosphorylation activity of PI3K, Akt, and mTOR was performed with Western blot. Our studies found that Fraxiparine significantly inhibited the invasive, migratory, and adhesive characteristics of A549 and 95D cells after 24 h incubation and showed a dose-dependent manner. Fraxiparine influenced the actin cytoskeleton rearrangement of A549 and 95D cells by preventing F-actin polymerization. Moreover, Fraxiparine could significantly inhibit CXCL12-mediated chemotactic migration of A549 and 95D cells in a concentration-dependent manner. Furthermore, Fraxiparine might destroy the interaction between CXCL12-CXCR4 axis, then suppress the PI3K-Akt-mTOR signaling pathway in lung cancer cells. For the first time, our data indicated that Fraxiparine could significantly inhibit the motility of lung cancer cells by restraining the actin cytoskeleton reorganization, and its related mechanism might be through inhibiting PI3K-Akt-mTOR signaling pathway mediated by CXCL12-CXCR4 axis. Therefore, Fraxiparine would be a potential drug for lung cancer metastasis therapy.

Background: MicroRNAs (miRNAs) play important roles in many biological processes, including cancer development. Among those miRNAs, miR-143 shows tumor-suppressive activity in some human cancers. However, the function and mechanism of miR-143 in lung cancer cells remains unknown. Here we explored the role of miR-143 in lung cancer. Results: According to qRT-PCR, we found that miR-143 was notably down-regulated in 19 NSCLC tissues and 5 cell lines. In vitro experiments showed us that miR-143 could significantly suppress the migration and invasion of NSCLC cell lines while it had no effects on the growth of NSCLC cell lines, and in vivo metastasis assay showed the same results. Finally, we found that the mechanism of miR-143 inhibiting the migration and invasion of NSCLC might be through targeting CD44v3. Conclusions: The up-regulated miR-143 in lung cancer could significantly inhibit cell migration and invasion, and this might work through targeting CD44v3, which was newly identified by us.