Juan Wang

M6A‐mediated hsa_circ_0061179 inhibits DNA damage in ovarian cancer cells via miR‐143‐3p/TIMELESS

AbstractOvarian cancer (OC) is among the most common and deadly solid malignancies in women. Despite many advances in OC research, the incidence of OC continues to rise, and its pathogenesis remains largely unknown. Herein, we elucidated the function of hsa_circ_0061179 in OC. The levels of hsa_circ_0061179, miR‐143‐3p, TIMELESS, and DNA damage repair‐related proteins in OC or normal ovarian tissues and cells were measured using real‐time quantitative polymerase chain reaction and immunoblotting. The biological effects of hsa_circ_0061179 and miR‐143‐3p on proliferation, clone formation, DNA damage, and apoptosis of OC cells were detected by the cell counting kit‐8 assay, 5‐methylethyl‐2′‐deoxyuridine, flow cytometry, the comet assay, and immunofluorescence staining combined with the confocal microscopy. The interaction among hsa_circ_0061179, miR‐143‐3p, and TIMELESS was validated by the luciferase reporter assay. Mice tumor xenograft models were used to evaluate the influence of hsa_circ_0061179 on OC growth in vivo. We found that human OC biospecimens expressed higher levels of hsa_circ_0061179 and lower levels of miR‐143‐3p. Hsa_circ_0061179 was found to bind with miR‐143‐3p, which directly targets TIMELESS. Hsa_circ_0061179 knockdown or miR‐143‐3p overexpression suppressed the proliferation and clone formation of OC cells and increased DNA damage and apoptosis of OC cells via the miR‐143‐3p/TIMELESS axis. Furthermore, we demonstrated that METTL3 could direct the formation of has_circ_0061179 through a specific m6A modification site. YTHDC1 facilitated the cytoplasmic transfer of has_circ_0061179 by directly binding to the modified m6A site. Our findings suggest that hsa_circ_0061179 acts as the sponge of miR‐143‐3p to activate TIMELESS signaling and inhibits DNA damage and apoptosis in OC cells.

Osthole inhibits proliferation and induces autophagy-dependent ferroptosis of cervical cancer cells through induction of TFR1

Osthole (OST), a natural coumarin, exerts its anticancer effects by inducing cancer cell necroptosis, apoptosis, pyroptosis or autophagy. In He La cells, OST cause mitochondrial atrophy, increased membrane density and reduced cristae, which are characteristics of ferroptosis. However, the mechanisms of OST-induced ferroptosis in cervical cancer cells remain unclear. In the present study, we found that OST inhibited He La cells' proliferation which triggered ferroptosis. Further studies showed that ferroptosis or autophagy inhibition could reverse the inhibitory effects of OST on He La cell proliferation, and significantly inhibited ferroptosis and autophagy induced by OST. Moreover, autophagy stimulation enhanced the ferroptosis induction of OST, while ferroptosis induction in turn enhanced the autophagy levels caused by OST. Furthermore, Transferrin Receptor 1 (TRF-1) silencing effectively reduced OST-induced ferroptosis and autophagy, while TFR1 overexpression notably enhanced OST-induced ferroptosis and autophagy in He La cells. In addition, animal experiments demonstrated that overexpression of TFR1 effectively suppressed tumor growth in cervical cancer He La cells, and its expression was associated with the activation of ferroptosis and autophagy. In conclusion, our study revealed the detailed mechanism of OST-induced He La cells ferroptosis and autophagy, and the association between autophagy and ferroptosis in OST-induced cell death.

Hsa_circ_0001445 works as a cancer suppressor via miR‐576‐5p/SFRP1 axis regulation in ovarian cancer

AbstractBackgroundOvarian cancer (OC) has high mortality and morbidity. Circular RNA (circRNA) can deeply impact the tumor occurrence and growth. The pathogenic activity of one particular circRNA, hsa_circ_0001445 (hcR1445), in OC remains unclear and was therefore analyzed in this study.MethodsHuman OC tissue specimens and cell lines (SKOV3, HO8910, and OVCAR8) were used to examine the levels of hcR1445 and the microRNA miR‐576‐5p using polymerase chain reaction. The 5‐ethynyl‐2′‐deoxyuridine, flow cytometry, cellular scratch test, CCK‐8, and Transwell migration assays were used to examine the biological activities of hcR1445 and miR‐576‐5p on cell apoptosis, invasion, migration, and proliferation in OC cells. Protein expression of WNT/β‐catenin and secreted frizzled‐related protein 1 (SFRP1) were tested using Western blot analysis. The potential interactions of miR‐576‐5p/SFRP1 and hcR1445/miR‐576‐5p were evaluated using a dual‐luciferase report assay. The effect of hcR1445 on OC growth and metastasis was further determined using an OC tumor xenograft model in vivo.ResultshcR1445 level was declined in OC cells and tissues. hcR1445 reduced cellular invasion, proliferation, and migration by blocking the ability of miR‐576‐5p to upregulate SFRP1 expression and consequently prohibit WNT/β‐catenin signal transduction. hcR1445 upregulation suppressed OC growth, development, and intraperitoneal metastasis in vivo.ConclusionhcR1445 acts an antioncogene by targeting the miR‐576‐5p/SFRP1 axis and blocking OC progression and development. Thus, hcR1445 may be employed as an indicator or a possible therapeutic target in OC patients.

Clinical characteristics and risk factors of invasion in extramammary Paget’s disease of the vulva

This study aimed to evaluate the risk factors of recurrence and invasive disease in patients with extramammary Paget's disease of the vulva (EPDV). We performed a retrospective analysis of patients who were initially diagnosed with EPDV in Fudan University Shanghai Cancer Center between May 2006 and March 2019. Thirty-eight patients were initially diagnosed with EPDV in our institution. Among them, 29 had intraepithelial EPDV, 8 had intraepithelial EPDV with stromal invasion, and 1 had an underlying vulvar adenocarcinoma. In total, 8 (21%) patients had 12 recurrences. Of these eight patients, four had one recurrence, while other four had two recurrences. Intraepidermal EPDV recurred nine times, while intraepidermal EPDV with invasive disease recurred thrice. The first and second recurrence intervals were 62.1 (9-146) months and 22 (15-28) months, respectively. The rate of invasive disease was 23.7% (9/38) for primary EPDV and 25% (3/12) for recurrent ones. We determined that the presence of invasive disease was associated with a history of more than 10 years (p = 0.02) and inversely correlated with positive margins (p = 0.037), However, invasive disease had no statistical relations with age (p = 0.438), recurrence (p = 0.642), and lesion diameter (p = 0.08). EPDV with a history of more than 10 years was associated with invasive disease. Close and long-term follow-up are recommended to identify those who require further treatment.

Guanosine monophosphate synthase upregulation mediates cervical cancer progression by inhibiting the apoptosis of cervical cancer cells via the Stat3/P53 pathway

Guanosine monophosphate synthase (GMPS) participates in chromatin and gene regulation in multiple types of organisms, and is highly expressed in a variety of human malignancies. The purpose of the present study was to explore the expression of GMPS and its role in cervical cancer (CC), and to provide ideas for improving the clinical efficacy of CC treatment. In the present study, immunohistochemistry, reverse transcription‑quantitative PCR analysis, Cell Counting Kit‑8 assay, 5‑ethynyl‑2'‑deoxyuridine assay, flow cytometry, western blotting and immunofluorescence assays were conducted to detect the expression of GMPS in normal cervical tissues, CC tissues, para‑cancerous tissues and CC cell lines. Moreover, the present study detected the effect of GMPS knockdown on CC cell proliferation, clonal formation ability, aging and apoptosis, as well as on the expression levels of apoptosis‑related proteins in tumor cells. The present results demonstrated that the expression level of GMPS in CC was significantly higher compared with that of adjacent tissues; the expression rate of GMPS in CC was 57.36%. GMPS expression was found to successively and gradually increase from that in normal cervical tissues, to that in cervical intraepithelial neoplasia and CC tissues. The abnormal expression of GMPS was positively associated with the degree of CC differentiation and the depth of early invasion. Small interfering (si)RNA knockdown of GMPS inhibited proliferation and colony formation, and promoted aging and apoptosis of CC cells. Furthermore, subcutaneous injection of GMPS‑knockdown tumor cells in nude mice resulted in a decrease in the proliferative ability of the tumor. The animal experimental results showed that the tumor growth rate of the short hairpin (sh)RNA‑GMPS group was significantly slower than that of the HeLa sh‑negative control group. It was identified that GMPS may inhibit CC cell senescence and apoptosis via the Stat3/P53 molecular pathway. Collectively, the present results suggested that GMPS may be a marker of unfavorable prognosis of CC, and it may also be a potential therapeutic target for CC.