RNF216 affects the stability of STAU2 in the hypothalamus.

Idiopathic hypogonadotropic hypogonadism (IHH) is a rare disease characterized by gonadal failure due to deficiency in gonadotropin-releasing hormone (GnRH) synthesis, secretion, or action. RNF216 variants have been recently identified in patients with IHH. Ring finger protein 216 (RNF216), as a ubiquitin E3 ligase, catalyzes the ubiquitination of target proteins with high specificity, which consequently modulates the stability, localization, and interaction of the target protein. In this study, we found that RNF216 interacted with Staufen2 (STAU2) and affected the stability of STAU2 through the ubiquitin-proteasome pathway. STAU2, as a double-stranded RNA-binding protein enriched in the nervous system, plays a role in RNA transport, RNA stability, translation, anchoring, and synaptic plasticity. Further, we revealed that STAU2 levels in the hypothalamus of RNF216-/- mice were increased compared with wild-type (WT) mice. The change in STAU2 protein homeostasis may affect a series of RNA cargoes. Therefore, we analyzed the changes in RNA levels in the hypothalamus of RNF216-/- mice and WT mice by RNA sequencing. We found that deletion of RNF216 led to decreased activities of the prolactin signaling pathway, neuroactive ligand-receptor interaction, GnRH signaling pathway, and ovarian steroidogenesis. The weakening of these signal pathways is likely to affect the secretion of GnRH, thereby affecting the development of gonads. Therefore, our study suggests that STAU2 may be a potential therapeutic target for IHH. Further experiments are needed to demonstrate the association between the weakening of these signaling pathways and the RNA-binding protein STAU2.

MiR-93/HMGB3 regulatory axis exerts tumor suppressive effects in colorectal carcinoma cells.

OBJECTIVE: MicroRNA (miR)-93 has been proven to mediate the initiation and progression of colorectal carcinoma (CRC); however, the mechanisms by which miR-93 mediates CRC development need deeper elucidation. The present study is designed to investigate the association between miR-93 and high mobility group box 3 (HMGB3), as well as the functions of miR-93, in CRC. METHODS: miR-93 expression was quantified by RT-qPCR. CRC cells were transfected or cotransfected with miR-93 mimic, miR-93 inhibitor, pcDNA3.1-HMGB3 and sh-HMGB3, and then the proliferative, migratory and invasive capacities were detected in addition to the apoptotic rate. Western blotting assessed the expression levels of HMGB3, PI3K, p-PI3K, AKT and p-AKT. The interaction between miR-93 and HMGB3 was identified. RESULTS: In CRC tissues, miR-93 was downregulated and HMGB3 was upregulated. LOVO and SW480 cells transfected with miR-93 mimic exhibited reduced proliferation, invasion and migration as well as increased apoptosis. The ratios of p-PI3K/PI3K and p-AKT/AKT were declined after miR-93 mimic was introduced into the CRC cell lines. miR-93 negatively downregulated HMGB3, and introduction of pcDNA3,1-HMGB3 could counteract, in part, the inhibitory effects of miR-93 on the malignant properties of CRC cells as well as the ratios of p-PI3K/PI3K and p-AKT/AKT. CONCLUSION: miR-93 targeted HMGB3 to block the activation of the PI3K/AKT pathway and thus enhance CRC cell apoptosis.

[Screening of interacting proteins of idiopathic gonadotropin-releasing hormone deficiency pathogenic gene RNF216].

OBJECTIVE: To screen proteins interacting with ring finger protein 216(RNF216) through yeast two hybrid experiment, and further clarify the role of RNF216 in the pathogenesis of gonadotropin-releasing hormone deficiency. METHODS: A recombinant expression vector pGBKT7-RNF216 was constructed and transformed into yeast Y2HGold, which was hybridized with a human cDNA library in order to screen proteins interacting with RNF216. The interaction was verified in yeast Y2HGold. RESULTS: A recombinant expression vector pGBKT7-RNF216 was successfully constructed and expressed in yeast Y2HGold. Filamin B (FLNB) was identified by yeast two hybrid experiment, and their interaction was verified in yeast Y2HGold. CONCLUSION: An interaction between FLNB and RNF216 was identified through yeast two hybrid experiment. RNF216 may affect the proliferation and migration of GnRH neurons by regulating FLNB or FLNB/FLNA heterodimers.

C-type Lectin Domain Family 4 Member G (CLEC4G) Is a Negative Marker for CD34 in the Evolution of Liver Pathogenesis.

OBJECTIVE: This study aimed to explore the expression of the C-type lectin domain family 4 member G (CLEC4G) gene in the liver sinusoidal endothelial cells (LSECs) during liver pathogenesis, and to evaluate its correlation with CD34 and clinical significance in hepatocellular carcinoma patients. METHODS: We conducted bioinformatics analysis of the differential expression of CLEC4G in various human organs, carcinomatous and adjacent tissues. Then, mRNA and protein expression levels of CD34 in hepatocellular carcinoma (HCC) samples were detected via real-time quantitative reverse transcription PCR (qRT-PCR) and immunohistochemical (IHC), respectively. ELISA was applied to detect serum levels of CLEC4G in healthy controls, liver fibrosis and HCC patients. RESULTS: The expressions of mRNA and protein levels of CLEC4G were higher in normal liver tissues, moderately expressed in cirrhotic and para-cancerous tissues (P<0.001), and lowest in HCC tissues (P<0.001). We also found high CD34 expression in tumors, which was negatively correlated with CLEC4G at both mRNA and protein levels. Compared to the healthy controls, the CLEC4G levels in liver fibrosis patients and HCC patients gradually became lower (P<0.001). CONCLUSIONS: The low expression of CLEC4G is potentially correlated with LSEC capillarization and the appearance of micro-vessels. Such a phenomenon may serve as a reliable diagnostic marker for hepatocellular carcinoma.

Dihydromyricetin induced lncRNA MALAT1-TFEB-dependent autophagic cell death in cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (CSCC) is the second most common skin cancer. Dihydromyricetin (DHM), a Rattan tea extract, has been shown to have antitumor activity with no obvious toxicity to normal cells in vitro and in vivo. However, its efficacy in the treatment of CSCC and the underlying antitumor mechanism has not been fully elucidated yet. In our study, DHM increased autophagic flux in the A431 cells, as evidenced by the upregulation of LC3-II and downregulation of P62/SQSTM1. Moreover, the pharmacological or genetic blocking autophagy decreased DHM-induced cell death, indicating DHM triggered autophagic cell death in A431 cells. Specifically, DHM induced TFEB(Ser142) de-phosphorylation, activated TFEB nuclear translocation and increased of TFEB reporter activity, which contributed to the expression of autophagy-related genes and subsequent initiated autophagic cell death in A431 cells. Importantly, DHM decreased lncRNA MALAT1 expression and MALAT1 overexpression abrogated the effects of DHM on TFEB-dependent autophagy both in vitro and in vivo. Taken together, DHM induces CSCC cell death via inducing excessive autophagy, which is mediated through the MALAT1-TFEB pathway. Therefore, DHM may be beneficial for the development of chemotherapy for CSCC.

Anticancer activity of crocin against cervical carcinoma (HeLa cells): Bioassessment and toxicity evaluation of crocin in male albino rats.

The present study was aimed to investigate anticancer activity of crocin against cervical carcinoma and bio-assessment and toxicological evaluation in male albino rats. Effect of crocin on cell viability (anticancer activity) was determined against cervical carcinoma cells. Chronic effect of crocin on body weight changes, serum enzymes, serum biochemical markers, lipid peroxidation, hematological markers and DNA damage in male albino rats were determined. Cell survival rate was reduced 98.4, 95.7, 87.2, 81.1 and 73.1% at 25, 50, 75, 100 and 125 mg/l of crocin respectively. Cell viability was reduced 97.1, 96.4, 85.5, 78.4 and 70.2% at 25, 50, 75, 100 and 125 mg/l of crocin respectively. Crocin reduced body weight significantly at 30 and 60th day. Alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), blood urea nitrogen (BUN), creatinine, bilirubin, albumin and total protein were decreased, while glucose, cholesterol, TG, and GSH were increased. Hemoglobin (Hb), white blood cells (WBC), lymphocytes, neutrophil and packed cell volume (PCV) were altered following crocin treatment. Necrosis, fibrosis, mononuclear infiltration, angiogenesis and DNA fragmentation were also noted. Taking all these data together, it is suggested that the crocin could be a potential antitumor agent against cervical carcinoma. However, the altered histological, biochemical and hematological markers may lead to an adverse effect on the cellular metabolism and physiological activity.