Although the roles of lncRNA FOXD2-AS1 have been investigated in many types of cancers including colorectal cancer (CRC), its functionality remains to be further investigated. Analysis of the TCGA data set revealed that FOXD2-AS1 was up-regulated in CRC tissues. This study aimed to analyze the function of FOXD2-AS1 in CRC. Methods: FOXD2-AS1 expression was detected by qPCR. A 5-year follow-up study was performed to analyze the prognostic value of FOXD2-AS1 for CRC. Overexpression experiments were performed to analyze the interactions among FOXD2-AS1, miR-25-3p and Sema4C. Transwell assays were performed to analyze cell invasion and migration. Results: In this study, we further confirmed the up-regulation of FOXD2-AS1 in CRC patients and showed that high FOXD2-AS1 level predicted poor survival. Bioinformatics analysis showed that miR-25-3p may bind FOXD2-AS1, while over-expression experiments showed no effects on each other's expression. Instead, FOXD2-AS1 over-expression led to the up-regulate Sema4C, which is a target of miR-25-3p. Transwell assay showed that FOXD2-AS1 and Sema4C over-expression led to the increased invasion and migration rates of CRC cells. MiR-25-3p plays the opposite role and attenuated the effects of FOXD2-AS1 and Sema4C over-expression. Conclusion: FOXD2-AS1 may regulate the miR-25-3p/Sema4C axis to promote the invasion and migration of CRC cells.

BackgroundRelatively poor penetration and retention in tumor tissue has been documented for large molecule drugs including therapeutic antibodies and recombinant immunoglobulin constant region (Fc)-fusion proteins due to their large size, positive charge, and strong target binding affinity. Therefore, when designing a large molecular drug candidate, smaller size, neutral charge, and optimal affinity should be considered.MethodsWe engineered a recombinant protein by molecular engineering the second domain of VEGFR1 and a few flanking residues fused with the Fc fragment of human IgG1, which we named HB-002.1. This recombinant protein was extensively characterized both in vitro and in vivo for its target-binding and target-blocking activities, pharmacokinetic profile, angiogenesis inhibition activity, and anti-tumor therapeutic efficacy.ResultsHB-002.1 has a molecular weight of ~80 kDa, isoelectric point of ~6.7, and an optimal target binding affinity of <1 nM. The pharmacokinetic profile was excellent with a half-life of 5 days, maximal concentration of 20.27 μg/ml, and area under the curve of 81.46 μg · days/ml. When tested in a transgenic zebrafish embryonic angiogenesis model, dramatic inhibition in angiogenesis was exhibited by a markedly reduced number of subintestinal vessels. When tested for anti-tumor efficacy, HB-002.1 was confirmed in two xenograft tumor models (A549 and Colo-205) to have a robust tumor killing activity, showing a percentage of inhibition over 90% at the dose of 20 mg/kg. Most promisingly, HB-002.1 showed a superior therapeutic efficacy compared to bevacizumab in the A549 xenograft model (tumor inhibition: 84.7% for HB-002.1 versus 67.6% for bevacizumab, P < 0.0001).ConclusionsHB-002.1 is a strong angiogenesis inhibitor that has the potential to be a novel promising drug for angiogenesis-related diseases such as tumor neoplasms and age-related macular degeneration.

Introduction The aim of this study was to investigate the role and mechanism of long non-coding RNA (lncRNA) TRG-AS1 in mediating the proliferation, invasion and migration of lung cancer cells as well lung tumor growth. Methods Firstly, the expression levels of TRG-AS1, miR-224-5p in lung cancer tissues or cells were quantified by quantitative real-time PCR. Western blot analysis was conducted to measure the expression levels of protein SMAD4. CCK-8 assay, wound healing assay and transwell assay were conducted to evaluate cell proliferation, migration and invasion, respectively. The interaction between TRG-AS1 and miR-224-5p was predicted by bioinformatics analysis. Dual-luciferase assay and RNA pull-down assay were performed to further confirm their interaction. In addition, the interaction between miR-224-5p and SMAD4 was detected by RIP assay. Results The results showed that TRG-AS1 was highly upregulated and miR-224-5p was downregulated in lung cancer. A negative correlation was found between TRG-AS1 and miR-224-5p. Furthermore, upregulation of TRG-AS1 promoted cell proliferation and invasion, while overexpression of miR-224-5p attenuated the effects of TRG-AS1. The downstream protein SMAD4 played an important role. In vivo study showed that knockdown of TRG-AS1 effectively retarded tumor growth. Discussion Our data suggested that the TRG-AS1/miR-224-5p/SMAD4 axis may be a potential therapeutic target in lung cancer.