Search

Long non-coding RNAs (lncRNAs) is essential in regulation of cancer cell and cancer stem cells (CSCs) behaviour. Linc00662 is a newly identified human lung cancer related lncRNA. In this study, we aimed to explore the function of Linc00662 in human lung cancer. The expression level of Linc00662 was analysed by quantitative real-time PCR. Cell metastasis and invasive ability were detected by transwell and scratch wound healing assays. The stemness of CSCs was shown by tumorsphere formation assay and flow cytometry. The interaction between Linc00662 and Lin28 was confirmed by RNA immunoprecipitation and RNA pulldown assay. Overexpression of Linc00662 promoted the poor prognosis of lung cancer. Cell invasion, metastasis and CSCs stemness in H1299 and A549 could be influenced by Linc00662. Linc00662 had direct interaction with Lin28, and the Linc00662 function was dependent on Lin28. We demonstrate that overexpression of Linc00662 enhances lung cancer cell metastasis and CSC stemness by interacting with Lin28 in human lung cancer, which could be utilized as a potential diagnostic and therapeutic target for lung cancer patients. [ABSTRACT FROM AUTHOR]

We intended to clarify the role of sphingosine kinase 1 (SPHK1) in gastric cancer (GC) using both in vitro and in vivo assays. The study was designed to identify novel therapeutic targets for GC treatment. Differential analysis was utilized to dissect two gene expression omnibus series (GSE49515 and GSE79973) microarray data form Gene Expression Omnibus (GEO) (https://www.ncbi.nlm.nih.gov/geo/) dataset. MRNA and protein expressions were determined by quantitative polymerase chain reaction and Western blot, respectively. GC cell growth was measured by MTT assays and verified by in vivo analysis. Cell cycle and cell apoptosis were detected via flow cytometer observation. Cell migration and invasion were assessed by wound healing assays and Transwell assays. The targeting relationship between miRNA and SPHK1/S1PR1 was identified via dual‐luciferase assay. Twenty‐four common differentially expressed genes were screened out from two gene expression omnibus series (GSE49515 and GSE79973), among which SPHK1 was chosen for its higher fold change. We found elevated SPHK1 expression in GC tissues and cells, along with an increased concentration of SPHK1‐generated sphingosine‐1‐phosphate (S1P) in both GC serum and tissue. SPHK1 knockdown significantly suppressed cell proliferation, migration, and invasion of MKN1 and KATO3 cells. It also blocked cell cycle and induced apoptosis in MKN1 and KATO3 cells. Silencing of SPHK1 also refrained tumor growth and inhibited S1P level. MiR‐330‐3p directly targeted SPHK1 and S1PR1. Overexpressed miR‐330‐3p in MKN1 cells repressed SPHK1 and S1PR1 expressions like their chemical inhibitors‐SPHK1 inhibitors (FTY720) and S1PR1 inhibitors (VPC23019), and acted anti‐tumor both in vitro and in vivo. Our study provides evidence that SPHK1 was promotive for GC tumor growth and cell biological behaviors, and that miR‐330‐3p targeted 3′‐UTR of SPHK1 and inhibited its expression. SPHK1 was expected to become a new molecular marker and miR‐330‐3p a novel therapeutic target for GC. © 2018 IUBMB Life, 70(11):1164–1176, 2018 [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression of Mitofusin-2 (MFN2) in HCC tissues and its role in the development of HCC. Methods: A total of 107 HCC specimens were collected for tissue microarray analysis and immunohistochemistry (IHC) analysis. The relationship between MFN2 expression and clinical features of patients with HCC was analyzed. Results: Expression level of MFN2 in HCC tissues was 0.92 ± 0.78, significantly lower than that of matched paracancerous liver tissues (1.25 ± 0.75). Patients with low expression of MFN2 had significantly higher rates of cirrhosis than those with high expression of MFN2 (P = 0.049). Kaplan-Meier survival analysis showed that HCC patients with low expression of MFN2 had a worse prognosis in overall survival than HCC patients with high expression of MFN2 (P = 0.027). Patients with high expression of MFN2 had a better prognosis in disease-free survival compared with HCC patients with low expression of MFN2 (P = 0.047). Vascular invasion and MFN2 expression were shown to be prognostic variables for overall survival in patients with HCC. Multivariate analysis showed that vascular invasion (P < 0.001) and MFN2 expression (P = 0.045) were independent prognostic factors for overall survival. Vascular invasion (P < 0.001) and MFN2 expression (P = 0.042) were independent risk factors associated with disease-free survival. Conclusion: Our data revealed that MFN2 expression was decreased in HCC samples. High MFN2 expression was correlated with longer survival times in patients with HCC and served as an independent factor for better outcomes. Our study therefore provides a promising biomarker for the prognostic prediction of HCC and a potential therapeutic target for the disease. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a common pollutant with reproductive toxicity. Our previous study revealed that Cd triggered spermatogonia ferroptosis. However, the underlying mechanisms remain unclear. Nuclear receptor coactivator 4 (NCOA4) mediates ferritinophagy and specific degradation of ferritin through lysosomes, resulting in the release of ferrous ions. Excessive autophagy can lead to ferroptosis. This study investigated the role of autophagy in Cd-triggered ferroptosis using GC-1 spermatogonial (spg) cells which exposed to CdCl 2 (5 μM, 10 μM, or 20 μM) for 24 without/with CQ. The cells which transfected with Ncoa4-siRNA were used to explore the role of NCOA4-mediated ferritinophagy in Cd-triggered ferroptosis. The results revealed that Cd caused mitochondrial swelling, rupture of cristae, and vacuolar-like changes. The Cd-treated cells exhibited more autophagosomes. Simultaneously, Cd increased intracellular iron, reactive oxygen species, and malondialdehyde concentrations while decreasing glutathione content and Superoxide Dismutase-2 activity. Moreover, Cd upregulated mRNA levels of ferritinophagy-associated genes (Ncoa4, Lc3b and Fth1), as well as enhanced protein expression of NCOA4, LC3B, and FTH1. While Cd decreased the mRNA and protein expression of p62/SQSTM1. These results showed that Cd caused ferritinophagy and ferroptosis. The use of chloroquine to inhibit autophagy ameliorated Cd-induced iron overload and ferroptosis. Moreover, Ncoa4 knockdown in spermatogonia significantly reduced intracellular iron concentration and alleviated Cd-triggered ferroptosis. In conclusion, our findings demonstrate that Cd activates the ferritinophagy pathway mediated by NCOA4, resulting in iron accumulation through ferritin degradation. This causes oxidative stress, ultimately initiating ferroptosis in spermatogonia. Our results may provide new perspectives and potential strategies for preventing and treating Cd-induced reproductive toxicity. [Display omitted] • Cd causes iron overload and triggers ferroptosis in spermatogonia. • Cd induces ferritinophagy in spermatogonia. • CQ antagonizes against Cd-caused iron overload in spermatogonia. • NCOA4-mediated ferritinophagy participates in Cd-triggered ferroptosis. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress mediates Cd-caused germ cell apoptosis in testis. The effects of 4-phenylbutyric acid (PBA), a classical chaperone, were investigated on Cd-induced apoptosis in mouse GC-1 spermatogonia cells. The cells were pretreated with PBA before Cd exposure. TUNEL and flow cytometry assays were applied to determine apoptosis. Some key biomarkers of ER stress were analyzed using RT-PCR and western blot. as expected, the apoptotic cells exposed to Cd apparently increased. The mRNA and protein expression levels of GRP78 and ATF6α, were elevated in the Cd groups. Additional experiments displayed that Cd notably increased IRE1α and JNK phosphorylation, and upregulated XBP-1 mRNA and protein expression. Moreover, p-eIF2α and CHOP expressions were clearly elevated in the Cd groups. Interestingly, PBA almost completely inhibited ER stress and protected spermatogonia against apoptosis induced by Cd. PBA alleviated Cd-induced ER stress and spermatogonia apoptosis, and may have the therapeutic role in Cd-induced male reproductive toxicity. • CdCl 2 induced spermatogonia apoptosis in vitro. • CdCl 2 triggered spermatogonia ER stress. • 4-PBA alleviated CdCl 2 -induced spermatogonia apoptosis. [ABSTRACT FROM AUTHOR]