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Nanozyme technology as an emerging field has been successfully applied to chemical sensing, biomedicine, and environmental monitoring. It is very significant for the advance of this field to construct nanozymes with high catalytic activity by a simple method and to develop their multifunctional applications. Here, a new type of cobalt-doped carbon dots (Co-CDs) nanozymes was designed using vitamin B

Background Despite extensive molecular epidemiological studies, the prevalence and characteristics of Mouse Mammary Tumor Virus-Like Virus (MMTV-LV) in Chinese women breast cancer are still unclear. Besides, the prevalence of MMTV-LV in women breast cancer tissue varies in different countries and its dependent factors remain inconclusive. Methods In the first part of the study, a case-control study was performed. 119 breast cancer samples (84 from Northern China and 35 from Southern China) and 50 breast fibroadenoma specimens were collected from Chinese women patients. MMTV-like env sequence and the homology to MMTV env gene were analysed by semi-nested polymerase chain reaction (PCR). We also explored the association of MMTV-LV prevalence with sample sources (Southern and Northern China) and patients’ clinicopathological characteristics. To investigate the dependent factors of the prevalence of MMTV-LV in breast cancer worldwide, a meta-analysis was conducted in the second part of the study. Results We found that the prevalence of MMTV-LV was much higher in breast cancer tissues (17.65%) than that in breast fibroadenoma specimens (4.00%) (P P P Conclusion The distribution of house mice may be a crucial environmental factor that explains the geographic differences in human breast cancer incidence. Our findings may provide a potential avenue of prevention, diagnosis and treatment for breast cancer.

Purpose To determine whether early proteins from high-risk human papillomavirus (HPV) have the capacity to maintain cellular stemness. Patients and methods First, we isolated cancer stem cell like cells from two cervical cancer cell lines, SiHa and CaSki, using non-adhesive culture with serum-free medium. Second, we knocked down HPV16 E7 in SiHa sphere cells and overexpressed HPV16 E7 in U2OS sphere cells. Third, we used RNA-seq analysis and Western blotting to screen and identify the expression of differentially expressed genes in SiHa cells with HPV16 E7 knockdown. Results We found that both SiHa and CaSki cells grew as cell spheres (oncospheres) and shared the properties of cancer stem cells, including high expression of stem cell marker OCT4 and SOX2, self-renew, and resistance to chemotherapeutic drugs. The stem-like properties were deprived when HPV16 E7 was knocked down in SiHa sphere cells and maintained when HPV16 E7 was over-expressed in U2OS sphere cells. APH1B was up-regulated, among differential expression genes, in SiHa cells with HPV16 E7 knockdown and modulated cellular stemness and SiHa sphere cells with APH1B knockdown regained the stem-like properties deprived by E7 inhibition. Conclusion HPV16 E7 possesses the capacity to maintain cellular stemness and APH1B may participate in this process in cervical cancer sphere cells.

Background Cancer stem cells (CSCs) possess abilities of self-renewal and differentiation, have oncogenic potential and are regarded to be the source of cancer recurrence. However, the mechanism by which CSCs maintain their stemness remains largely unclear. Methods In this study, the cell line-derived ovarian CSCs (OCSCs), 3AO and Caov3, were enriched in serum-free medium (SFM). Differentially expressed proteins were compared between the OCSC subpopulation and parental cells using liquid chromatography (LC)-mass spectrometry (MS)/MS label-free quantitative proteomics. Sphere-forming ability assays, flow cytometry, quantitative real-time polymerase chain reaction (qPCR), western blotting, and in vivo xenograft experiments were performed to evaluate stemness. RNA-sequencing (RNA-seq) and pyrosequencing were used to reveal the mechanism by which STON2 negatively modulates the stem-like properties of ovarian cancer cells. Results Among the 74 most differentially expressed proteins, stonin 2 (STON2) was confirmed to be down-regulated in the OCSC subpopulation. We show that STON2 negatively modulates the stem-like properties of ovarian cancer cells, which are characterized by sphere formation, a CD44+CD24− ratio, and by CSC- and epithelial mesenchymal transition (EMT)-related markers. STON2 knockdown also accelerated tumorigenesis in NOD/SCID mice. Further investigation revealed a downstream target, mucin 1 (MUC1), as up-regulated upon the down regulation of STON2. A decrease in both DNA methyltransferase 1 (DNMT1) expression and methylation in the promoter region of MUC1 was associated with subsequently elevated MUC1 expression, as detected in STON2 knockdown in 3AO and Caov3 cells. Direct DNMT1 knockdown simultaneously elevated MUC1 expression. The functional significance of this STON2-DNMT1/MUC1 pathway is supported by the observation that STON2 overexpression suppresses MUC1-induced sphere formation of OCSCs. The paired expression of STON2 and MUC1 in ovarian cancer specimens was also detected revealing the prognostic value of STON2 expression to be highly dependent on MUC1 expression. Conclusions Our results imply that STON2 may negatively regulate stemness in ovarian cancer cells via DNMT1-MUC1 mediated epigenetic modification. STON2 is therefore involved in OCSC biology and may represent a therapeutic target for innovative treatments aimed at ovarian cancer eradication. Electronic supplementary material The online version of this article (10.1186/s13046-018-0977-y) contains supplementary material, which is available to authorized users.

BackgroundMetastasis is the key cause of death in ovarian cancer patients. To figure out the biological nature of cancer metastasis is essential for developing effective targeted therapy. Here we investigate how long non-coding RNA (lncRNA) SPOCD1-AS from ovarian cancer extracellular vesicles (EVs) remodel mesothelial cells through a mesothelial-to-mesenchymal transition (MMT) manner and facilitate peritoneal metastasis.MethodsEVs purified from ovarian cancer cells and ascites of patients were applied to mesothelial cells. The MMT process of mesothelial cells was assessed by morphology observation, western blot analysis, migration assay and adhesion assay. Altered lncRNAs of EV-treated mesothelial cells were screened by RNA sequencing and identified by qRT-PCR. SPOCD1-AS was overexpressed or silenced by overexpression lentivirus or shRNA, respectively. RNA pull-down and RNA immunoprecipitation assays were conducted to reveal the mechanism by which SPOCD1-AS remodeled mesothelial cells. Interfering peptides were synthesized and applied. Ovarian cancer orthotopic implantation mouse model was established in vivo.ResultsWe found that ovarian cancer-secreted EVs could be taken into recipient mesothelial cells, induce the MMT phenotype and enhance cancer cell adhesion to mesothelial cells. Furthermore, SPOCD1-AS embedded in ovarian cancer-secreted EVs was transmitted to mesothelial cells to induce the MMT process and facilitate peritoneal colonization in vitro and in vivo. SPOCD1-AS induced the MMT process of mesothelial cells via interacting with G3BP1 protein. Additionally, G3BP1 interfering peptide based on the F380/F382 residues was able to block SPOCD1-AS/G3BP1 interaction, inhibit the MMT phenotype of mesothelial cells, and diminish peritoneal metastasis in vivo.ConclusionsOur findings elucidate the mechanism associated with EVs and their cargos in ovarian cancer peritoneal metastasis and may provide a potential approach for metastatic ovarian cancer therapeutics.

The prognosis of advanced stage cervical cancer is poorer due to cancer invasion and metastasis. Exploring new factors and signalling pathways associated with invasiveness and metastasis would help to identify new therapeutic targets for advanced cervical cancer. We searched the cancer microarray database, Oncomine, and found elevated calponin 3 (CNN3) mRNA expression in cervical cancer tissues. QRT-PCR verified the increased CNN3 expression in cervical cancer compared to para-cancer tissues. Proliferation, migration and invasion assays showed that overexpressed CNN3 promoted the viability and motility of cervical cancer cells, the opposite was observed in CNN3-knockdown cells. In addition, xenografted tumours, established from SiHa cells with CNN3 knockdown, displayed decreased growth and metastasis in vivo. Furthermore, RNA-sequencing showed that ribosomal protein lateral stalk subunit P1 (RPLP1) was a potential downstream gene. Gene function experiments revealed that RPLP1 had the same biological effects as CNN3 did. Rescue experiments demonstrated that the phenotypes inhibited by CNN3 silencing were partly or completely reversed by RPLP1 overexpression. In conclusion, we verified that CNN3 acts as an oncogene to promote the viability and motility of cervical cancer cells in vitro and accelerate the growth and metastasis of xenografted tumours in vivo, by affecting RPLP1 expression.

Objective As cancer stem cells (CSCs) are considered as the origin of tumor development, recurrence, and drug resistance, we aimed to explore the mechanism related to modulating stemness in CSCs, thus facilitating to search for new therapeutic strategy for ovarian cancer. Methods In this study, ovarian cancer stem cells (OCSCs) induced from cell line 3AO and A2780 were enriched in serum-free medium (SFM). The effect of SURF4 on CSC-like properties was evaluated by sphere-forming assays, re-differentiation assays, quantitative real-time polymerase chain reaction, flow cytometry, Western blotting, cell viability assays and in vivo xenograft experiments. The downstream molecule participating in SURF4 maintaining stemness was screened by RNA-sequencing and identified by the experiments of gene function. Results SURF4 was upregulated expressed in OCSCs. Knockdown of SURF4 reduced the expression of the related stem markers (SOX2 and c-MYC), inhibited self-renewal ability, and improved the sensitivity to chemotherapeutic drugs (paclitaxel and cisplatin) in OCSCs. SURF4 knockdown also inhibited tumorigenesis in nonobese diabetic/severe combined immunodeficiency mice. BIRC3 expression was controlled by SURF4, and BIRC3 showed the similar effect as SURF4 did, and BIRC3 overexpression partially recovered stem-like properties abolished by SURF4 knockdown. Conclusion Our findings suggest that SURF4 possesses the ability to maintain stemness of OCSCs via BIRC3, and may serve as a potential target in stem cell-targeted therapy for ovarian cancer.

Purpose To determine whether early proteins from high-risk human papillomavirus (HPV) have the capacity to maintain cellular stemness. Patients and methods First, we isolated cancer stem cell like cells from two cervical cancer cell lines, SiHa and CaSki, using non-adhesive culture with serum-free medium. Second, we knocked down HPV16 E7 in SiHa sphere cells and overexpressed HPV16 E7 in U2OS sphere cells. Third, we used RNA-seq analysis and Western blotting to screen and identify the expression of differentially expressed genes in SiHa cells with HPV16 E7 knockdown. Results We found that both SiHa and CaSki cells grew as cell spheres (oncospheres) and shared the properties of cancer stem cells, including high expression of stem cell marker OCT4 and SOX2, self-renew, and resistance to chemotherapeutic drugs. The stem-like properties were deprived when HPV16 E7 was knocked down in SiHa sphere cells and maintained when HPV16 E7 was over-expressed in U2OS sphere cells. APH1B was up-regulated, among differential expression genes, in SiHa cells with HPV16 E7 knockdown and modulated cellular stemness and SiHa sphere cells with APH1B knockdown regained the stem-like properties deprived by E7 inhibition. Conclusion HPV16 E7 possesses the capacity to maintain cellular stemness and APH1B may participate in this process in cervical cancer sphere cells.

Interleukin (IL)-37, a new IL-1 family member, has received increasing attention in recent years. In the past decade, it has been determined that IL-37 is expressed in various normal cells and tissues and is regulated by inflammatory stimuli and pro-cytokines via different signal transduction pathways. Recently, it has been found that IL-37 is expressed in a variety of cancers, chronic inflammatory and autoimmune disorders, and exerts anti-inflammatory effects. Moreover, a growing body of literature demonstrates that IL-37 plays a vital role in inhibiting both innate and adaptive immune responses as well as inflammatory reactions. In addition, IL-37 may prove to be a new and potentially useful target for effective cytokine therapy. Further evidence is needed to clarify in more detail the effects of IL-37 in experimental and clinical studies. Based on an extensive summary of published data, the aim of this review is to outline the current knowledge of IL-37, including the location, structure, expression, regulation and function, as well as the potential clinical applications of this cytokine.

Table S1. Primer sequences used in this study (DOCX 18 kb)

Table S2. Target sequences in this study. (DOCX 18 kb)

As a well-characterized master player in epigenetic regulatory network, EZH2 is widely implicated in the development of many malignancies. We previously found that EZH2 promoted Wnt/β-catenin activation through downregulation of CXXC4 expression. In this report, we demonstrated that CXXC4 inhibited MAPK signaling through binding to ERK-1/2 and abrogating the interaction of ERK 1/2 with MEK1/2. L183, the critical residue in CXXC4 ERK D domain, was found to be essential for CXXC4–ERK 1/2 interaction and the growth inhibitory effect of CXXC4 in human cancer cells. In summary, CXXC4 directly disrupted MEK1/2–ERK 1/2 interaction to inactivate MAPK signaling. L183 site is indispensable for the binding of CXXC4 to ERK1/2 and growth inhibitory effect of CXXC4. Therefore, EZH2 can activate MAPK signaling by inhibiting CXXC4 expression.

Doxorubicin induces DNA damage to exert its anti-cancer function. Histone deacetylase 1 (HDAC1) can protect the genome from DNA damage. We found that doxorubicin specifically downregulates HDAC1 protein expression and identified HDAC1 as a target of miR-520h, which was upregulated by doxorubicin. Doxorubicin-induced cell death was impaired by exogenous HDAC1 or by miR-520h inhibitor. Moreover, HDAC1 reduced the level of γH2AX by preventing the interaction of doxorubicin with DNA. In summary, doxorubicin downregulates HDAC1 protein expression, by inducing the expression of HDAC1-targeting miR-520h, to exacerbate DNA–doxorubicin interaction. The upregulation of HDAC1 protein may contribute to drug resistance of human cancer cells and targeting HDAC1 is a promising strategy to increase the clinical efficacy of DNA damage-inducing chemotherapeutic drugs.

MicroRNAs (miRNAs) are small non-coding RNAs involved in the initiation and progression of several types of human cancer, including hepatocellular carcinoma (HCC), which is one of the most common types of cancer and the third leading cause of cancer-related mortality worldwide. Mounting evidence has demonstrated that miRNAs play a vital role in HCC, hepatitis, alcoholic liver disease, liver cell development and the metabolic functions of the liver. The aim of the present review was to summarize the most recent findings on the functions of miRNAs in the liver and discuss their potential roles in the diagnosis, prognosis and treatment of HCC.

Autophagy is a self-proteolytic process that degrades intracellular material to enable cellular survival under unfavorable conditions. However, how autophagy is activated in human carcinogenesis remains largely unknown. Herein we report an epigenetic regulation of autophagy in human cancer cells. YY1 (YY1 transcription factor) is a well-known epigenetic regulator and is upregulated in many cancers. We found that YY1 knockdown inhibited cell viability and autophagy flux through downregulating SQSTM1 (sequestosome 1). YY1 regulated SQSTM1 expression through the epigenetic modulation of the transcription of MIR372 (microRNA 372) which was found to target SQSTM1 directly. During nutrient starvation, YY1 was stimulated to promote SQSTM1 expression and subsequent autophagy activation by suppressing MIR372 expression. Similar to YY1 depletion, MIR372 overexpression blocked autophagy activation and inhibited in vivo tumor growth. SQSTM1 upregulation and competent autophagy flux thus contributed to the oncogenic function of YY1. YY1-promoted SQSTM1 upregulation might be a useful histological marker for cancer detection and a potential target for drug development.

It has been approved for the clinical application of β-elemene to treat various cancers mainly brain tumors in China. In the present study, we found that β-elemene significantly inhibited the in vitro growth of human breast cancer cells by inducing apoptosis. In addition, β-elemene also induced the conversion of LC3-I into LC3-II as well as the formation of autolysosomes, indicating the activation of autophagy. Interestingly, inhibition of autophagy significantly potentiated the growth-inhibitory effect of β-elemene on breast cancer cells. In summary, β-elemene induced cytoprotective autophagy in human breast cancer cells in addition to apoptosis. Inhibition of autophagy significantly enhanced the cytotoxicity of β-elemene to human breast cancer cells. Therefore, combination of β-elemene with autophagy inhibitors could be a promising strategy for the treatment of breast cancer.

Despite a large number of molecular epidemiological studies, the association of Mouse Mammary Tumor Virus-Like Virus (MMTV-LV) infection with the risk of human breast cancer remains inconclusive mainly due to the heterogeneity in populations involved. We performed a systematic search of multiple bibliographic databases, up to October 2013, to identify all studies on detection of MMTV-LV DNA in human breast cancer using polymerase chain reaction (PCR) and conducted the first comprehensive meta-analysis of published literature to explore the relevance of MMTV-LV to human breast cancer. As a result, meta-analysis of twelve case-control studies identified from the systematic search revealed a significantly increased risk for breast cancer development after MMTV-LV infection (OR=15.20; 95% CI: 9.98-23.13). However, there was no significant correlation between MMTV-LV infection and the transformation from ductal carcinoma in situ to invasive ductal carcinoma (OR=1.16; 95% CI: 0.27-4.97). In addition, MMTV-LV infection was not associated with the expression of estrogen receptor (ER) (OR=0.89; 95% CI: 0.48-1.65), progesterone receptor (PR) (OR=0.73; 95% CI: 0.22-2.42), HER-2 (OR=0.65; 95% CI: 0.30-1.43) or p53 (OR=1.47; 95% CI: 0.79-2.73). Finally, we found that the prevalence of MMTV-LV in breast carcinoma was significantly higher in patients from Western countries (prevalence=40.4%, 95% CI: 28.9%-51.9%) than in Asian patients (prevalence: 8.5%; 95% CI: -7.1%-24.1%) in a subgroup and meta-regression analysis (p=0.015). In summary, the meta-analysis of published studies revealed a significantly increased risk for breast cancer development after MMTV-LV infection. In addition, the prevalence of MMTV-LV is much higher in breast cancer patients from Western countries than Asian patients.