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Background DNA damage is one of the critical contributors to the occurrence and development of some cancers. APEX1 and APEX2 are the most important molecules in the DNA damage, and APEX1 has been identified as a diagnostic and prognostic biomarker in liver hepatocellular carcinoma (LIHC). However, the expression of APEX2 and its functional mechanisms in LIHC are still unclear. Aim To examine the expression of APEX2 and the potential mechanism network in LIHC. Methods We conducted a pan-cancer analysis of the expression of APEX1 and APEX2 using the interactive TIMER tool. GEO datasets, including GSE14520, GSE22058, and GSE64041, were used to compare the APEX2 expression level in tumor tissues and adjacent non-tumor tissues. Then, we calculated the 5-year survival rate according to the web-based Kaplan-Meier analysis. We included the TCGA liver cancer database in GSEA analysis based on the high and low APEX2 expression, showing the potential mechanisms of APEX2 in LIHC. After that, we conducted Pearson correlation analysis using GEPIA2. Next, we performed quantitative polymerase chain reaction (qPCR) assay to examine the APEX2 levels in normal liver cell line LO2 and several liver cancer cell lines, including HepG2, Huh7, SMMC7721, and HCCLM3. APEX2 in HCCLM3 cells was knocked down using small interfering RNA. The role of APEX2 in cell viability was confirmed using CCK-8. Dual-luciferase reporter assay was performed to examine the promoter activity of CCNB1 and MYC. Results APEX1 and APEX2 are both highly expressed in the tumor tissues of BLCA, BRCA, CHOL, COAD, ESCA, HNSC, LIHC, LUAD, LUSC, READ, and STAD. APEX2 overexpression in LIHC was validated using GSE14520, GSE22058, and GSE64041 datasets. The survival analysis showed that LIHC patients with high expression of APEX2 had a lower overall survival rate, even in the AJCC T1 patients. High level of APEX2 could indicate a lower overall survival rate in patients with or without viral hepatitis. The GSEA analysis identified that kinetochore and spindle microtubules are the two main cellular components of APEX2 in GO Ontology. APEX2 was also positively associated with molecular function regulation of chromosome segregation and DNA replication. The results of KEGG analysis indicated that APEX2 expression was positively correlated with cell cycle pathway and pro-oncogenic MYC signaling. Pearson correlation analysis showed that APEX2 had a significant positive correlation with CCNB1 and MYC. APEX2 level was higher in liver cancer cell lines than in normal liver LO2 cells. Small interfering RNA could knock down the APEX2 expression in HCCLM3 cells. Knockdown of APEX2 resulted in a decrease in the viability of HCCLM3 cells as well as the expression and promoter activity of CCNB1 and MYC. Conclusion APEX2 is overexpressed in LIHC, and the higher APEX2 level is associated with a worse prognosis in overall survival. APEX2 is closely involved in the biological processes of chromosome segregation and DNA replication. APEX2 expression is positively correlated with the pro-oncogenic pathways. Knockdown of APEX2 could inhibit the cell viability and CCNB1 and MYC pathways, suggesting that APEX2 is an oncogene in LIHC, which could be a potential pharmaceutic target in the anti-tumor therapy.

Background We aimed to determine the safety and effectiveness of laparoscopic-assisted surgery (LAS) in visceral obesity patients with colorectal cancer (CRC). Patients and methods We retrospectively collected the clinical data of consecutive patients who underwent colorectal surgery for CRC between August 2014 and July 2018. The third lumbar vertebra visceral fat area was measured to diagnose visceral obesity. One-to-one propensity score matching was performed to compare the short-term outcomes between the open surgery (OS) and LAS in visceral obesity patients. Univariate and multivariate analyses were performed to evaluate the risk factors of postoperative complications. Results A total of 280 visceral obesity patients were included in this study with 140 patients for each group. Compared with the OS group, the LAS group had more lymph nodes harvested, longer surgical duration, and shorter postoperative hospital stay. The overall incidence of complications in OS was significantly higher than LAS (32.1 vs. 20.0%, P=0.021). Multivariate analysis revealed that age of at least 65 years (odds ratio: 1.950, 95% confidence interval: 1.118-3.403; P=0.019) was an independent risk factor for postoperative complications, whereas LAS (odds ratio: 0.523, 95% confidence interval: 0.302-0.908; P=0.021) was a protective factor. Conclusion LAS in visceral obesity patients with CRC was a safer and less invasive alternative than open surgery, with fewer complications within the first 30 days postoperatively.

Accumulating evidence indicates that circular RNAs (circRNA) exert crucial functions in the development and advance of cancers. CircRNA_100290 has been reported to promote proliferation in oral cancer. However, whether it participates in colorectal cancer (CRC) remains unclear. Here, our report showed that circRNA_100290 level was significantly increased in CRC tissues and cell lines. Besides, circRNA_100290 expression was positively correlated with tumor metastasis while inversely correlated with prognosis. Silencing circRNA_100290 markedly reduced cell proliferation rate, inhibited migration and invasion abilities, but promoted apoptosis in vitro. Mechanistically, our data revealed circRNA_100290 was a competing endogenous RNA (ceRNA) of FZD4 by sponging miR-516b, leading to activation of Wnt/β-catenin pathway. Rescue assay indicated that FZD4-induced activation of β-catenin pathway is indispensable for the function of circRNA_100290 in CRC. In summary, our study for the first time revealed a novel regulatory loop of circRNA_100290/miR-516b/FZD4/Wnt/β-catenin implicated in CRC progression.

Reaction of [60]fullerene with α-alkoxyl/phenolyl/acyloxyl ketoxime in the presence of sodium carbonate afforded fulleroisoxazoline or fullerooxazine derivatives via C–C or C–O bond cleavage respectively. O 2 was proved to be essential to the reaction.

An efficient protocol for the synthesis of methano[60]fullerene derivatives linked with a single electron-withdrawing group has been developed through one-step reaction of [60]fullerene with active halides mediated by CuBr/pentamethyldiethylenetriamine. Many functional groups including esters, ketones, amides, and sulfonyl groups could be easily introduced onto the fullerene skeleton by using this methodology. A plausible reaction mechanism, but not the atom transfer radical process, was proposed for the formation of the methano[60]fullerene derivatives.

An efficient one-step strategy for the synthesis of fulleroisoxazolines/fulleropyrazolines from fullerene and aldoximes/hydrazones mediated by PhI(OAc)2 has been described.

A new type of stable C 60 -fused dihydrooxazine derivatives was successfully prepared by the hetero-Diels–Alder reaction of C 60 with nitrosoalkene generated in situ by extrusion of HBr from the corresponding α-bromooxime.

The cis-isomer (III) is the unexpected major product while in the thermal reaction only the cis-product can be obtained.

An efficient one-step strategy for the synthesis of fulleroisoxazolines/fulleropyrazolines from fullerene and aldoximes/hydrazones mediated by PhI(OAc)2 has been described.