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Long non-coding RNA LIFR-AS1 is low-expressed in many cancers, but its functions in papillary thyroid carcinoma (PTC) were not defined and require further study. The relationship between LIFR-AS1 expression and clinicopathological characteristics of patients with PTC was statistically analyzed. The downregulation of LIFR-AS1 in PTC tissues and cell lines was predicted by bioinformatics analysis and verified by qRT-PCR. After overexpressing or silencing LIFR-AS1, the regulatory role of LIFR-AS1 in PTC was examined by performing MTT, colony formation, wound healing, Transwell, ELISA, tube formation and xenograft tumor experiment. MiR-31-5p and SID1 transmembrane family member 2 (SIDT2) expressions in PTC tissues or cell lines were detected by qRT-PCR, Western blot, or in situ hybridization. The relationship between miR-31-5p and LIFR-AS1/SIDT2 was predicted by LncBase, TargetScan or Pearson correlation test and then verified by Dual-Luciferase Reporter assay, RNA pull-down assay and qRT-PCR. The regulatory effect of LIFR-AS1/miR-31-5p/SIDT2 axis on the biological behaviors of PTC cells was confirmed by functional experiments and rescue experiments mentioned above. The tumor size and lymphatic metastasis were correlated with LIFR-AS1 overexpression. Overexpressed LIFR-AS1 suppressed tumorigenesis in vivo . LIFR-AS1 and SIDT2 expressions were suppressed in PTC tissues, while that of miR-31-5p was elevated in PTC tissues. LIFR-AS1 was negatively correlated with miR-31-5p. LIFR-AS1 sponged miR-31-5p to upregulate SIDT2, thereby inhibiting the viability, proliferation, migration, invasion, and the secretion of vascular endothelial growth factor (VEGF) of PTC cells and angiogenesis of human umbilical vein endothelial cells (HUVECs). This paper demonstrates that LIFR-AS1/miR-31-5p/SIDT2 axis modulated the development of PTC.

N 6 -methyladenosine (m 6 A) modification, the most abundant internal methylation of eukaryotic RNA transcripts, is critically implicated in RNA processing. There is extensive evidence indicating that long non-coding RNAs (lncRNAs) serve as key regulators of oncogenesis and tumor progression in humans. Through prior study has assessed that LIFR-AS1 plays a key role in various kinds of malignant tumors. However, the exact role of m 6 A induced LIFR-AS1 in pancreatic cancer (PC) and its potential molecular mechanisms remain largely unknown. In this study, we determined that PC cell lines and tumors exhibit increased LIFR-AS1 expression that correlates with larger tumor size, lymph node metastasis, and more advanced TNM stage. Functionally, loss-of-function studies indicated that LIFR-AS1 knockdown decreased the proliferation, migration, and invasion of PC cells in vitro. Mechanistically, we found that METTL3 induced m 6 A hyper-methylation on the 3' UTR of LIFR-AS1 to enhance its mRNA stability and LIFR-AS1 could directly interact with miR-150-5p, thereby indirectly up-regulating VEGFA expressions within cells. Through rescue experiments, we were able to confirm that the unfavorable impact of LIFR-AS1 knockdown on VEGFA /PI3K/Akt Signaling could be reversed via the inhibition of miR-150-5p expression. Together, these findings indicate that a noval m6A-LIFR-AS1 axis promotes PC progression at least in part via regulation of the miR-150-5p/VEGFA axis, indicating that this regulatory axis may be a viable clinical target for the treatment of PC.

Within the immune system there is an exquisite ability to discriminate between "self" and "non-self" that is orchestrated by T lymphocytes. Discriminatory pathways guide differentiation of these lymphocytes into either regulatory (Treg) or effector (Teff) T cells, influenced by cues from the naïve T cell's immediate micro-environment as it responds to cognate antigen. Reciprocal pathways may lead to commitment of naïve T cells into either the protective tolerance-promoting Treg, or to the pro-inflammatory Th17 effector phenotype. Primary activation of CD4(+) lymphocytes stimulates their release of leukemia inhibitory factor (LIF), and Treg continue to release LIF in response to antigen, implying a role for LIF in tolerance. In contrast, interleukin- 6 (IL-6), although very closely related to LIF, promotes maturation of Th17 cells. Here we show that LIF and IL-6 behave as polar opposites in promoting commitment to the Treg and Th17 lineages. Unlike IL6, LIF supported expression of Foxp3, the Treg lineage transcription factor, and LIF opposed IL6 by suppressing IL-6-induced IL-17A protein release. In striking contrast, we found that IL6 effectively inhibited LIF signalling, repressing transcription of the LIF receptor gp190, and strongly inducing axotrophin/MARCH-7, a novel E3 ubitquitin ligase that we discovered to be active in degradation of gp190 protein. In vivo, anti-LIF treatment reduced donor-specific Treg in recipients of foreign spleen cells. Conversely, a single dose of biodegradable LIF nanoparticles, targeted to CD4, successfully manipulated the LIF/IL6 axis towards development of donor-specific Foxp3(+) Treg. The implications for therapy are profound, harnessing endogenous immune regulation by paracrine delivery of LIF to CD4(+) cells in vivo.