A novel protein FNDC3B-267aa encoded by circ0003692 inhibits gastric cancer metastasis via promoting proteasomal degradation of c-Myc.

BACKGROUND: Gastric cancer (GC) ranks fifth in global cancer incidence and third in mortality rate among all cancer types. Circular RNAs (circRNAs) have been extensively demonstrated to regulate multiple malignant biological behaviors in GC. Emerging evidence suggests that several circRNAs derived from FNDC3B play pivotal roles in cancer. However, the role of circFNDC3B in GC remains elusive. METHODS: We initially screened circFNDC3B with translation potential via bioinformatics algorithm prediction. Subsequently, Sanger sequencing, qRT-PCR, RNase R, RNA-FISH and nuclear-cytoplasmic fractionation assays were explored to assess the identification and localization of circ0003692, a circRNA derived from FNDC3B. qRT-PCR and ISH were performed to quantify expression of circ0003692 in human GC tissues and adjacent normal tissues. The protein-encoding ability of circ0003692 was investigated through dual-luciferase reporter assay and LC/MS. The biological behavior of circ0003692 in GC was confirmed via in vivo and in vitro experiments. Additionally, Co-IP and rescue experiments were performed to elucidate the interaction between the encoded protein and c-Myc. RESULTS: We found that circ0003692 was significantly downregulated in GC tissues. Circ0003692 had the potential to encode a novel protein FNDC3B-267aa, which was downregulated in GC cells. We verified that FNDC3B-267aa, rather than circ0003692, inhibited GC migration in vitro and in vivo. Mechanistically, FNDC3B-267aa directly interacted with c-Myc and promoted proteasomal degradation of c-Myc, resulting in the downregulation of c-Myc-Snail/Slug axis. CONCLUSIONS: Our study revealed that the novel protein FNDC3B-267aa encoded by circ0003692 suppressed GC metastasis through binding to c-Myc and enhancing proteasome-mediated degradation of c-Myc. The study offers the potential applications of circ0003692 or FNDC3B-267aa as therapeutic targets for GC.

Attempted retrieval of guidewire fragment using the twisting wire technique causes coronary perfusion: Case report.

RATIONALE: Guidewire fracture is one of the biggest risks of percutaneous coronary intervention, twisting wire technique is very useful for retrieving the fractured wire, but the potential risks have been inadequately reported. Herein, we present a case of retrieval of guidewire fragments using the twisting wire technique that causes coronary perfusion. PATIENT CONCERNS: A 37-year-old male patient was admitted to our hospital for elective percutaneous coronary intervention of the left circumflex coronary artery. CLINICAL FINDINGS: For chronic total occlusion of the distal left circumflex coronary artery, antegrade recanalization by wire escalation, and parallel wire techniques were attempted. However, we shockingly found that the BMW guidewire, anchored in the right coronary artery, spontaneously fractured from the proximal right coronary artery, and a lengthy fragment of the guidewire remained in the coronary. DIAGNOSES, INTERVENTIONS, AND OUTCOMES: Many attempts were made to retrieve the remnant guidewire including the twisting wire technique, which leads to the perforation of the coronary. OUTCOMES: Finally, percutaneous retrieving procedures were stopped in favor of surgical extraction via a small coronary arteriotomy. This procedure was successful. LESSONS: To the best of our knowledge, the present case is the first reported spontaneous fracture of the guidewire. Leaving such a lengthy remnant guidewire in the artery, or leaving stenting over the wire, would impose a high risk of coronary thrombosis, perforation, and embolization. Yet, the perforation of the artery that occurred in this case, which could have had life-threatening consequences, resulted from our attempts to retrieve the guidewire using the twisting wire technique.

Redescription of three species of Aponychus from China with ontogenetic development and morphological variations of A. corpuzae (Acariformes: Tetranychidae).

Ontogenetic development of leg chaetotaxy, stylophore and striae of the dorsal integument, and variations of leg setal counts and length of idiosomal setae in Aponychus corpuzae are discussed. The following changes were observed during the ontogenetic development of A. corpuzae: the depth of the depression in stylophore increases; the dorsal striae gradually reduce in number and prominence; the length of dorsal setae sc1, c12, d12 and e1 reduce in size; adult dorsal setae much thicker than those of immature stages. There are a significant number of setae suppressed in A. corpuzae, often resulting in unique patterns and sexual dimorphism. The adult males and females of Aponychus firmianae and A. taishanicus from mainland China are redecribed, and a key to all Aponychus from mainland China is provided.