LncRNA PKMYT1AR promotes cancer stem cell maintenance in non-small cell lung cancer via activating Wnt signaling pathway.

Non-small cell lung cancer (NSCLC) is the most common type of human lung cancers, which has diverse pathological features. Although many signaling pathways and therapeutic targets have been defined to play important roles in NSCLC, limiting efficacies have been achieved. Bioinformatics methods were used to identify differential long non-coding RNA expression in NSCLC. Real-time RT-PCR experiments were used to examine the expression pattern of lncRNA PKMYT1AR, miR-485-5p. Both in vitro and in vivo functional assays were performed to investigate the functional role of PKMYT1AR/miR-485-5p/PKMYT1 axis on regulating cell proliferation, migration and tumor growth. Dual luciferase reporter assay, fluorescent in situ hybridization (FISH), immunoblot, co-immunoprecipitation experiments were used to verify the molecular mechanism. Here, we identify a human-specific long non-coding RNA (lncRNA, ENST00000595422), termed PKMYT1AR (PKMYT1 associated lncRNA), that is induced in NSCLC by Yin Yang 1 (YY1) factor, especially in cancerous cell lines (H358, H1975, H1299, H1650, A549 and SPC-A1) compared to that in normal human bronchial epithelium cell line (BEAS-2B). We show that PKMYT1AR high expression correlates with worse clinical outcome, and knockdown of PKMYT1AR inhibits tumor cell proliferation, migration and xenograft tumor formation abilities. Bioinformatic analysis and a luciferase assay demonstrate that PKMYT1AR directly interacts with miR-485-5p to attenuate the inhibitory role on its downstream oncogenic factor PKMYT1 (the protein kinase, membrane-associated tyrosine/threonine 1) in NSCLC. Furthermore, we uncover that miR-485-5p is downregulated in both cancerous cell lines and peripheral blood serum isolated from NSCLC patients compared to reciprocal control groups. Consistently, forced expression of miR-485-5p inhibits the proliferation and migration abilities of tumor cells. Moreover, we provide evidence showing that PKMYT1AR targeting antisense oligonucleotide (ASO) dramatically inhibit tumor growth in vivo. Mechanistic study shows that PKMYT1AR/ miR-485-5p /PKMYT1 axis promotes cancer stem cells (CSCs) maintenance in NSCLC via inhibiting β-TrCP1 mediated ubiquitin degradation of β-catenin proteins, which in turn causes enhanced tumorigenesis. Our findings reveal the critical role of PKMYT1AR/miR-485-5p /PKMYT1 axis during NSCLC progression, which could be used as novel therapeutic targets in the future.

He Y ，Jiang X ，Duan L ，Xiong Q ，Yuan Y ，Liu P ，Jiang L ，Shen Q ，Zhao S ，Yang C ，Chen Y ... -  《Molecular Cancer》

KDM2B mediates the Wnt/β-catenin pathway through transcriptional activation of PKMYT1 via microRNA-let-7b-5p/EZH2 to affect the development of non-small cell lung cancer.

The significance of KDM2B in oncogenesis has been appreciated, but the mechanism behind is incompletely understood. In this work, we addressed its effects on the progression of non-small cell lung cancer (NSCLC). Overexpression of KDM2B was linked to dismal prognoses of NSCLC patients. Based on the expression levels of KDM2B in a panel of NSCLC cell lines, A549, showing lower level of expression, and SK-MES-1, showing higher levels of expression, were selected as model systems to evaluate the effect of KDM2B overexpression and KDM2B silencing, respectively. Knockdown of KDM2B hampered NSCLC cell proliferation, invasion, as well as migration, while enhanced apoptosis. Additionally, KDM2B repressed the expression of microRNA (miR)-let-7b-5p through demethylation modification of H3K36me2, thereby promoting the expression of zester homolog 2 (EZH2), the target gene of let-7b-5p in NSCLC. Moreover, EZH2 transcriptionally induced the expression of PKMYT1 to activate the Wnt/β-catenin pathway. Sh-EZH2 and sh-PKMYT1 neutralized the supporting effects of KDM2B on cell proliferation, invasion and migration. Additionally, deletion of KDM2B reduced the xenograft volumes in nude mice. In conclusion, KDM2B induces the EZH2/PKMYT1/Wnt/β-catenin axis by inhibiting the let-7b-5p expression, which promotes NSCLC growth. More investigations are essential to determine the oncogenic role of KDM2B in NSCLC.

Zhang X ，Yin Z ，Li C ，Nie L ，Chen K ... -  《-》

[Overexpression of lncRNA FEZF1-AS1 promotes progression of non-small cell lung cancer via the miR-130a-5p/CCND1 axis].

Li F ，Xiang J ，Liu J ，Wang X ，Jiang H ... -  《-》

LncRNA SNHG1 contributes to the cisplatin resistance and progression of NSCLC via miR-330-5p/DCLK1 axis.

Long non-coding RNAs (lncRNAs) are involved in the occurrence and progression of multiple cancers, including non-small cell lung cancer (NSCLC). Herein, we explored the exact role and underlying mechanism of lncRNA small nucleolar RNA host gene 1 (SNHG1) in NSCLC. The levels of SNHG1, microRNA-330-5p (miR-330-5p) and doublecortin-like kinase 1 (DCLK1) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was carried out to measure the chemoresistance and proliferation of NSCLC cells. The metastasis and apoptosis of NSCLC cells were examined by transwell migration and invasion assays and flow cytometry. Western blot assay was conducted to detect the levels of proliferation-associated proteins and DCLK1. The interaction between miR-330-5p and SNHG1 or DCLK1 was predicted by StarBase and microT_CDS databases. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to validate these interactions. In vivo chemosensitivity experiment was conducted to assess the function of SNHG1 in the chemoresistance of NSCLC in vivo. SNHG1 was dramatically up-regulated in cisplatin (DDP)-resistant NSCLC tissues and cells. SNHG1 promoted the DDP resistance and malignant behaviors of NSCLC cells. SNHG1 functioned through targeting miR-330-5p, and si-SNHG1-mediated effects in NSCLC cells were attenuated by the addition of in-miR-330-5p. DCLK1 messenger RNA (mRNA) could directly bind to miR-330-5p, and miR-330-5p acted as a tumor suppressor in NSCLC through down-regulating DCLK1. SNHG1 silencing elevated the DDP sensitivity of NSCLC cells in vivo. SNHG1 elevated DDP resistance and malignant potential of NSCLC cells through elevating the level of DCLK1 via sponging miR-330-5p.

Ge P ，Cao L ，Zheng M ，Yao Y ，Wang W ，Chen X ... -  《-》

Upregulated lncRNA SNHG1 contributes to progression of non-small cell lung cancer through inhibition of miR-101-3p and activation of Wnt/β-catenin signaling pathway.

Cui Y ，Zhang F ，Zhu C ，Geng L ，Tian T ，Liu H ... -  《Oncotarget》