HELQ as a DNA helicase: Its novel role in normal cell function and tumorigenesis (Review).

Helicase POLQ­like (HELQ or Hel308), is a highly conserved, 3'­5' superfamily II DNA helicase that contributes to diverse DNA processes, including DNA repair, unwinding, and strand annealing. HELQ deficiency leads to subfertility, due to its critical role in germ cell stability. In addition, the abnormal expression of HELQ has been observed in multiple tumors and a number of molecular pathways, including the nucleotide excision repair, checkpoint kinase 1­DNA repair protein RAD51 homolog 1 and ATM/ATR pathways, have been shown to be involved in HELQ. In the present review, the structure and characteristics of HELQ, as well as its major functions in DNA processing, were described. Molecular mechanisms involving HELQ in the context of tumorigenesis were also described. It was deduced that HELQ biology warrants investigation, and that its critical roles in the regulation of various DNA processes and participation in tumorigenesis are clinically relevant.

Extracellular vesicles derived from cervical cancer cells carrying MCM3AP-AS1 promote angiogenesis and tumor growth in cervical cancer via the miR-93/p21 axis.

Tumor cells can promote angiogenesis by secreting extracellular vesicles (EVs). Meanwhile, tumor-derived EVs can carry long non-coding RNAs to activate pro-angiogenic signaling in endothelial cells. Here, we investigated the role of long non-coding RNA MCM3AP-AS1 carried by cervical cancer (CC) cell-derived EVs in the angiogenesis and the resultant tumor growth in CC, as well as the potential molecular mechanisms. LncRNAs significantly expressed in CC cell-derived EVs and CC were screened, followed by prediction of downstream target genes. EVs were isolated from HcerEpic and CaSki cell supernatants, followed by identification. The expression of MCM3AP-AS1 in CC was analyzed and its interaction with miR-93-p21 was confirmed. Following co-culture system, the role of MCM3AP-AS1 carried by EVs in HUVEC angiogenic ability, CC cell invasion and migration in vitro along with angiogenesis and tumorigenicity in vivo was assayed. MCM3AP-AS1 was overexpressed in CC cell-derived EVs as well as in CC tissues and cell lines. Cervical cancer cell-derived EVs could transfer MCM3AP-AS1 into HUVECs where MCM3AP-AS1 competitively bound to miR-93 and upregulate the expression of the miR-93 target p21 gene. Thus, MCM3AP-AS1 promoted angiogenesis of HUVECs. In the similar manner, MCM3AP-AS1 enhanced CC cell malignant properties. In nude mice, EVs-MCM3AP-AS1 induced angiogenesis and tumor growth. Overall, this study reveals that CC cell-derived EVs may transport MCM3AP-AS1 to promote angiogenesis and tumor growth in CC.

Prognostic Significance of the CXCLs and Its Impact on the Immune Microenvironment in Ovarian Cancer.

The chemokine (C-X-C motif) ligand (CXCL) family in tumor tissue is closely related to tumor growth, metastasis, and survival. However, the differential expression profile and prognostic value of the CXCLs in ovarian cancer (OC) have not been elucidated. Therefore, we studied the expression levels and mutations of CXCLs in OC patient in TCGA and various public databases. The expression differences of CXCLs in OC cancer tissues and normal tissues were compared through the Gene Expression Profiling Interactive Analysis (GEPIA) database. The effect of CXCLs on OC prognosis was analyzed using the Kaplan-Meier curves in GEPIA database. The impact of CXCLs on immune infiltration and clinicopathological outcomes in OC was assessed using the TIMER algorithm. Compared with normal tissues, we found that eight CXCLs were significantly differentially expressed in OC. The expression levels of CXCL9 (P = 0.0201), CXCL11 (P = 0.0385), and CXCL13 (P = 0.0288) were significantly associated with tumor stage. CXCL13 was the only gene that significantly affected both disease-free survival (DFS) and overall survival (OS) in OC, and higher CXCL13 transcript levels implied longer DFS and OS. Although there was no significant impact on DFS, CXCL10 (P = 0.0079) and CXCL11 (P = 0.0011) expression levels had a significant effect on OS in OC. At the same time, CXCLs were significantly associated with several immune-infiltrating cells in OC tissues. The CXCLs were significantly associated with one or more immune-infiltrating cells in OC tissue. CXCL13 was differentially expressed in OC and significantly affected the prognosis of patients and was a potential marker of OC prognosis.

FBP1 knockdown decreases ovarian cancer formation and cisplatin resistance through EZH2-mediated H3K27me3.

Worldwide, ovarian cancer (OC) is the seventh common cancer and the second most common cause of cancer death in women. Due to high rates of relapse, there is an urgent need for the identification of new targets for OC treatment. The far-upstream element binding protein 1 (FBP1) and enhancer of zeste homolog 2 (EZH2) are emerging proto-oncogenes that regulate cell proliferation and metastasis. In the present study, Oncomine data analysis demonstrated that FBP1 was closely associated with the development of OC, and The Cancer Genome Atlas (TCGA) data analysis indicated that there was a positive correlation between FBP1 and EZH2 in ovarian tissues. Moreover, we found that FBP1 knockdown suppressed tumor formation in nude mice and cisplatin resistance of OC cells, but the role of FBP1 in the cisplatin resistance of OC cells remained unclear. In addition, we verified physical binding between FBP1 and EZH2 in OC cells, and we demonstrated that FBP1 knockdown enhanced cisplatin cytotoxicity in OC cells and down-regulated EZH2 expression and trimethylation of H3K27. These results suggested that FBP1 increases cisplatin resistance of OC cells by up-regulating EZH2/H3K27me3. Thus, FBP1 is a prospective novel target for the development of OC treatment.

Baicalin promotes chondrocyte viability and the synthesis of extracellular matrix through TGF-ß/Smad3 pathway in chondrocytes.

BACKGROUND: Osteoarthritis (OA) is common in the elderly. Baicalin (BA) is a flavonoid monomer extracted from Scutellaria baicalensis Georgi, which has been reported to have anti-inflammatory, anti-deformation and anti-bacterial effects. METHODS: Cultures of micromass and 3D alginate beads, Alcian blue and Safranin O (SO)/fast green staining were used to investigate chondrocyte viability and extracellular matrix (ECM) synthesis in chondrocytes of all groups. The expression of SOX9, Smad3, Aggrecan (ACAN), type II collagen (Col2α), matrix metallopetidase 9 (MMP9), MMP13 and ADAMTS5 in chondrocytes of all groups were detected by western blot or qRT-PCR. RESULTS: The present study demonstrates that BA neutralized the IL-1ß-induced downregulation of chondrocyte viability and ECM secretion, including ACAN and Col2α. The downregulation of SOX9, and the upregulation of MMP9, MMP13 and ADAMTS5 induced by IL-1ß were reversed by BA treatment. Moreover, BA increased the nuclear translocation of Smad3 and SOX9 in chondrocytes cultured by micromass and 3D alginate beads. Interestingly, Smad3 inhibitor SIS3 reversed the promoting effect of BA on chondrocyte viability, ECM secretion, SOX9 and Smad3 nuclear translocation, and the inhibiting effect of BA on MMP9 and ADAMTS5 expressions. BA treatment also attenuated the decrease of Smad3 phosphorylation, SOX9 expression and the damage of cartilage integrity in mice which were induced by destabilization of the medial meniscus (DMM). CONCLUSION: BA promotes chondrocyte viability and the cell matrix synthesis through TGF-ß/Smad3 pathway in IL-1ß-treated chondrocytes and DMM treated mice. BA is a potential therapeutic target for OA.

Type II Collagen Sponges Facilitate Tendon Stem/Progenitor Cells to Adopt More Chondrogenic Phenotypes and Promote the Regeneration of Fibrocartilage-Like Tissues in a Rabbit Partial Patellectomy Model.

OBJECTIVE: Fibrocartilage transition zone (FC) is difficult to regenerate after surgical re-attachment of tendon to bone. Here, we investigated whether type II collagen-sponges (CII-sponges) facilitated tendon stem/progenitor cells (TSPCs) to adopt chondrogenic phenotypes and further observed if this material could increase the FC areas in bone-tendon junction (BTJ) injury model. METHODS: CII-sponges were made as we previously described. The appearance and pore structure of CII-sponges were photographed by camera and microscopies. The viability, proliferation, and differentiation of TSPCs were examined by LIVE/DEAD assay, alamarBlue, and PKH67 in vitro tracking. Subsequently, TSPCs were seeded in CII-sponges, Matrigel or monolayer, and induced under chondrogenic medium for 7 or 14 days before being harvested for qPCR or being transplanted into nude mice to examine the chondrogenesis of TSPCs. Lastly, partial patellectomy (PP) was applied to establish the BTJ injury model. CII-sponges were interposed between the patellar fragment and tendon, and histological examination was used to assess the FC regeneration at BTJ after surgery at 8 weeks. RESULTS: CII-sponges were like sponges with interconnected pores. TSPCs could adhere, proliferate, and differentiate in this CII-sponge up to 14 days at least. Both qPCR and immunostaining data showed that compared with TSPCs cultured in monolayer or Matrigel, cells in CII-sponges group adopted more chondrogenic phenotypes with an overall increase of chondrocyte-related genes and proteins. Furthermore, in PP injured model, much more new formed cartilage-like tissues could be observed in CII-sponges group, evidenced by a large amount of positive proteoglycan expression and typical oval or round chondrocytes in this area. CONCLUSION: Our study showed that CII-sponges facilitated the TSPCs to differentiate toward chondrocytes and increased the area of FCs, which suggests that CII-sponges are meaningful for the reconstruction of FC at bone tendon junction. However, the link between the two phenomena requires further research and validation.

[Corrigendum] High expression of FUSE binding protein 1 in breast cancer stimulates cell proliferation and diminishes drug sensitivity.

Subsequently to the publication of the above article, the authors have realized that they inadvertently uploaded an incorrectly labelled version of Fig. 5D; essentially, the row of data panels labelled as 'FBPI-KD' were the data derived from the experiments performed with the FBP1-C cells, and vice versa. The revised and correctly labelled version of Fig. 5, showing the data obtained from the experiments for the FBP1-C and the FBPI-KD cells for Fig. 5D, is shown below. The authors are grateful to the Editor of International Journal of Oncology for allowing them this opportunity to publish a Corrigendum, and apologize to the readership for any inconvenience caused.[the original article was published in International Journal of Oncology 57: 488-499, 2020; DOI: 10.3892/ijo.2020.5080].

Diversity roles of CHD1L in normal cell function and tumorigenesis.

Chromodomain helicase/ATPase DNA binding protein 1-like gene (CHD1L) is a multifunctional protein participated in diverse cellular processes, including chromosome remodeling, cell differentiation and development. CHD1L is a regulator of chromosomal integrity maintenance, DNA repair and transcriptional regulation through its bindings to DNA. By regulating kinds of complex networks, CHD1L has been identified as a potent anti-apoptotic and pro-proliferative factor. CHD1L is also an oncoprotein since its overexpression leads to dysregulation of related downstream targets in various cancers. The latest advances in the functional molecular basis of CHD1L in normal cells will be described in this review. As the same time, we will describe the current understanding of CHD1L in terms of structure, characteristics, function and the molecular mechanisms underlying CHD1L in tumorigenesis. We inference that the role of CHD1L which involve in multiple cellular processes and oncogenesis is well worth further studying in basic biology and clinical relevance.

Insights Into Amentoflavone: A Natural Multifunctional Biflavonoid.

Amentoflavone is an active phenolic compound isolated from Selaginella tamariscina over 40 years. Amentoflavone has been extensively recorded as a molecule which displays multifunctional biological activities. Especially, amentoflavone involves in anti-cancer activity by mediating various signaling pathways such as extracellular signal-regulated kinase (ERK), nuclear factor kappa-B (NF-κB) and phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), and emerges anti-SARS-CoV-2 effect via binding towards the main protease (Mpro/3CLpro), spike protein receptor binding domain (RBD) and RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. Therefore, amentoflavone is considered to be a promising therapeutic agent for clinical research. Considering the multifunction of amentoflavone, the current review comprehensively discuss the chemistry, the progress in its diverse biological activities, including anti-inflammatory, anti-oxidation, anti-microorganism, metabolism regulation, neuroprotection, radioprotection, musculoskeletal protection and antidepressant, specially the fascinating role against various types of cancers. In addition, the bioavailability and drug delivery of amentoflavone, the molecular mechanisms underlying the activities of amentoflavone, the molecular docking simulation of amentoflavone through in silico approach and anti-SARS-CoV-2 effect of amentoflavone are discussed.

Icariin inhibits the inflammation through down-regulating NF-κB/HIF-2α signal pathways in chondrocytes.

Articular cartilage injury or defect is a common disease and is mainly characterized by cartilage degradation because of chondrocyte inflammation. By now, there are no effective drugs and methods to protect articular cartilage from degradation. Icariin (ICA) is a typical flavonoid compound extracted from Epimedii Folium with anti-inflammatory and bone-protective effects. Our previous studies demonstrate that ICA up-regulates HIF-1α expression and glycolysis in chondrocytes and maintains chondrocyte phenotype. As another member of HIFs family, HIF-2α always plays a key role in inflammation. The effect of ICA on HIF-2α is unclear by now. In the present study, we confirmed the findings in our previous study that ICA promoted not only chondrocyte vitality and extracellular matrix (ECM) synthesis, but also the anti-inflammatory effect of ICA. In bone defect mice, ICA inhibited the expressions of NF-κB and HIF-2α. In TNF-α-treated ADTC5 chondrocytes, ICA neutralized the activation of IKK (IKK phosphorylation), the phosphorylation of IkB and NF-κB and the expression of HIF-2α. Furthermore, ICA inhibited the nucleus transfer of NF-κB and the expressions of MMP9 and ADAMTS5, two key targets of NF-κB/HIF-2α signal pathway. Taken together, the present study demonstrated that ICA may increase the vitality of chondrocytes by suppressing the inflammatory injury through the inhibition on NF-κB/HIF-2α signaling pathway. ICA is one effective candidate drug for the treatment of articular cartilage injury.

Amentoflavone triggers cell cycle G2/M arrest by interfering with microtubule dynamics and inducing DNA damage in SKOV3 cells.

Ovarian cancer is the seventh most common cancer and the second most common cause of cancer-associated mortality among gynecological malignancies worldwide. The combination of antimitotic agents, such as taxanes, and the DNA-damaging agents, such as platinum compounds, is the standard treatment for ovarian cancer. However, due to chemoresistance, development of novel therapeutic strategies for the treatment of ovarian cancer remains critical. Amentoflavone (AMF) is a biflavonoid derived from the extracts of Selaginella tamariscina, which has been used as a Chinese herb for thousands of years. A previous study demonstrated that AMF inhibits angiogenesis of endothelial cells and induces apoptosis in hypertrophic scar fibroblasts. In order to check the influence of AMF on cell proliferation, the effects of AMF on cell cycle and DNA damage were measured by cell viability, flow cytometry, immunofluorescence and western blotting assays in SKOV3 cells, an ovarian cell line. In the present study, treatment with AMF inhibited ovarian cell proliferation, increased P21 expression, decreased CDK1/2 expression, interrupted the balance of microtubule dynamics and arrested cells at the G2 phase. Furthermore, treatment with AMF increased the expression levels of phospho-Histone H2AX (γ-H2AX; a variant of histone 2A, that belongs to the histone 2A family member X) and the DNA repair protein RAD51 homolog 1 (Rad51), indicating the occurrence of DNA damage since γ-H2AX and Rad51 are both key markers of DNA damage. Consistent with previous findings, the results of the present study suggest that AMF is a potential therapeutic agent for the treatment of ovarian cancer. In addition, the effects of AMF on cell cycle arrest and DNA damage induction may be the molecular mechanisms by which AMF might exert its potential therapeutic benefits in ovarian cancer.

High expression of FUSE binding protein 1 in breast cancer stimulates cell proliferation and diminishes drug sensitivity.

Breast cancer is the most common malignant tumor affecting women worldwide and is divided into the following subtypes: Luminal A, Luminal B, HER­2 overexpression and triple­negative breast cancer (TNBC). TNBC accounts for approximately 15­20% of all breast cancer cases. Due to the characteristics of low differentiation, the likelyhood of recurrence and metastasis, strong invasiveness and the lack of hormone receptors and human epidermal growth factor receptor 2 (HER2), patients with TNBC cannot benefit from endocrine therapy or other available targeted agents. Chemotherapy is one of the main treatments for patients with TNBC, and cisplatin is one of the most commonly used and effective drugs. The human far upstream element binding protein 1 (FBP1) is a potent pro­proliferative and anti­apoptotic oncoprotein, which is overexpressed in numerous tumor types. The present study demonstrated that FBP1 and its target, c­Myc, were more highly expressed in breast cancer tissues compared with para­carcinoma tissues, and the FBP1 and c­Myc levels are decreased by cisplatin treatment. The knockdown of FBP1 in TNBC cells decreased cell proliferation by arresting the cell cycle at the G2 phase. The knockdown of FBP1 decreased the expression of G2 phase­associateed protein cyclin A2, whereas it increased that of cyclin B1 and p­CDC2. Furthermore, the knockdown of FBP1 decreased cell migration and metastasis by downregulating matrix metalloproteinase 2 expression, and enhanced the sensitivity of TNBC cells to cisplatin by inducing apoptosis. These results thus suggest that FBP1 is a potential novel biological marker for the diagnosis and treatment of TNBC.

Fibrochondrogenic differentiation potential of tendon-derived stem/progenitor cells from human patellar tendon.

BACKGROUND: Bone-tendon junction (BTJ) is a unique structure connecting tendon and bone through a fibrocartilage zone. Owing to its unique structure, the regeneration of BTJ remains a challenge. Here, we study the fibrochondrogenic differentiation of human tendon-derived stem/progenitor cells (TSPCs) both in vitro and in vivo. METHODS: TSPCs were isolated from human patellar tendon tissues and investigated for their multidifferentiation potential. TSPCs were cultured in chondrogenic medium with transforming growth factor beta 3 (TGF-ß3) and BMP-2 in vitro â€‹and examined for the expression of fibrochondrogenic marker genes by quantitative real-time reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and immunofluorescence. TSPCs pretreated were also seeded in collage II sponge and then transplanted in immunocompromised nude mice to examine if the fibrochondrogenic characteristics were conserved in vivo. RESULTS: We found that TSPCs were differentiated towards fibrochondrogenic lineage, accompanied by the expression of collagen I, collagen II, SRY-box transcription factor 9 (Sox 9), and tenascin C. Furthermore, after TSPCs were seeded in collagen II sponge and transplanted in immunocompromised nude mice, they expressed fibrochondrogenic genes, including proteoglycan, collagen I, and collagen II. CONCLUSION: Taken together, this study showed that TSPCs are capable of differentiating towards fibrocartilage-like cells, and the fibrochondrogenic characteristics were conserved even in vivo, and thus might have the potential application for fibrocartilage regeneration in BTJ repair. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: TSPCs are able to differentiate into fibrocartilage-like cells and thus might well be one potential cell source for fibrocartilage regeneration in a damaged BTJ repair.

Icariin increases chondrocyte vitality by promoting hypoxia-inducible factor-1α expression and anaerobic glycolysis.

BACKGROUND: Articular cartilage is a unique avascular tissue in which chondrocytes are embedded in extracellular matrix (ECM). The decreased ECM resulting from the loss of articular chondrocyte viability leads to degenerative diseases such as osteoarthritis (OA). This study aims to investigate the effect of icariin (ICA) on ECM synthesis and chondrocyte viability. METHODS: Micromass culture, alcian blue, and Safran O (SO)/fast green staining were used to investigate chondrocyte viability and ECM synthesis in chondrocytes treated with ICA. The expression of hypoxia-inducible factor-1α (HIF-1α), SOX9, and anaerobic glycolysis enzymes were detected by western blot and reverse transcription-quantitative polymerase chain reaction. RESULTS: ICA, an active flavonoid component of Herba epimedii, was demonstrated to increase chondrocyte viability and ECM synthesis. HIF-1α is a key mediator of chondrocyte response to fluctuations in oxygen availability during cartilage development or damage, and its expression was unregulated by ICA treatment. Meanwhile, ICA treatment increased SOX9 expression, which is a key regulator of ECM synthesis. Furthermore, ICA treatment increased the expression of glucose transporter 1 (GLUT1), glucose-6-phosphate dehydrogenase (G6PD), phosphoglycerate kinase 1 (PGK1), and pyruvate dehydrogenase kinase 1 (PDK1), which contribute to glucose transfer and anaerobic glycolysis. CONCLUSIONS: The present study revealed that ICA treatment facilitates chondrocyte vitality by promoting HIF-1α expression and anaerobic glycolysis. Therefore, ICA could be a novel clinical treatment for OA.

GSK343 induces programmed cell death through the inhibition of EZH2 and FBP1 in osteosarcoma cells.

Enhancer of zeste homolog 2 (EZH2) is an important member of the epigenetic regulatory factor polycomb group proteins (PcG) and is abnormally expressed in a wide variety of tumors, including osteosarcoma. Scientists consider EZH2 as an attractive target for the treatment of osteosarcoma and have found many potential EZH inhibitors, such as GlaxoSmithKline 343 (GSK343). It has been reported that GSK343 can be used as an inhibitor in different types of cancer. This study demonstrated that GSK343 not only induced apoptosis by increasing cleaved Casp-3 and poly ADP-ribose polymerase (PARP) expression, but also induced autophagic cell death by inhibiting p62 expression. Apoptosis and autophagic cell death induced by GSK343 were confirmed by the high expression of cleaved caspase-3, LC3-II and transmission electron microscopy. GSK343 inhibited the expression of EZH2 and c-Myc. Additionally, GSK343 inhibited the expression of FUSE binding protein 1 (FBP1), which was identified by its regulatory effects on c-Myc expression. Since c-Myc is a common target of EZH2 and FBP1, and GSK343 inhibited the expression of these proliferation-promoting proteins, a mutual regulatory mechanism between EZH2 and FBP1 was proposed. The knockdown of EZH2 suppressed the expression of FBP1; similarly, the knockdown of FBP1 suppressed the expression of EZH2. These results suggest the mutual regulatory association between EZH2 and FBP1. The knockdown of either EZH2 or FBP1 accelerated the sensitivity of osteosarcoma cells to GSK343. Based on these results, this study clarified that GSK343, an EZH2 inhibitor, may have potential for use in the treatment of osteosarcoma. The underlying mechanisms of the effects of GSK343 are partly mediated by its inhibitory activity against c-Myc and its regulators (EZH2 and FBP1).

Young age at diagnosis is associated with better prognosis in stage IV breast cancer.

Numerous studies have shown that young age is a risk factor in early breast cancer. But for stage IV breast cancer, it is unclear whether age has a similar effect on patient survival. We collected and analyzed data from patients with stage IV breast cancer between January 2010 and December 2015 in SEER database. Multivariate Cox proportional hazard model was used in this study. 13,069 patients with stage IV breast cancer were included in the analysis, of which 1,135 were young breast cancer patients (≤40 years old). In a multivariate analysis that adjusted for sociodemographic factors, clinical-pathological characteristics and therapeutic methods, the risk of death in patients with stage IV ≤40 years was significantly reduced (hazard ratio [HR], 0.72; 95% CI, 0.65-0.79). Subgroup analyses showed that, with the same adjustment of all factors, young age only significantly reduced the risk of death in patients with luminal A (HR, 0.78; 95% CI, 0.68-0.89) and luminal B (HR 0.46; 95% CI, 0.35-0.60) subtypes. Young age at diagnosis is associated with better survival in patients with stage IV breast cancer. The effect of young age at diagnosis on the survival outcome of stage IV breast cancer varies by subtypes.

Icariin suppresses cell cycle transition and cell migration in ovarian cancer cells.

Ovarian cancer is the third most common type of gynecological tumor, in addition to being the most lethal. Cytoreductive surgery with chemotherapy is the standard treatment for ovarian cancer. It is necessary to identify novel chemotherapeutic methods, since current chemotherapy treatments are rarely effective for patients with advanced­stage or recurrent ovarian cancer and may cause acute systemic toxicity. Icariin (ICA) is a prenylated flavonol glycoside derived from Herba Epimedii, a medicinal plant with a variety of pharmacological activities, including anticancer, antidiabetic and anti­obesity effects. By analyzing cell viability, cell cycle and cell migration, the present study demonstrated that ICA inhibited the cell viability of the ovarian cancer cell line, SKOV3, and blocked cell cycle transition. ICA inhibited the expression of fuse binding protein 1 (FBP1), a critical regulator of proliferation and tumorigenesis through binding to the c­Myc promoter, as well as ß­catenin, a key regulator in ovarian cancer initiation, metastasis, chemoresistance and recurrence. Furthermore, it was indicated that ICA inhibited the migration of SKOV3 cells. In accordance with our previous findings on high FBP1 expression in ovarian cancer, FBP1 was a potential target of ICA in ovarian cancer cells. Based on these results, the present study demonstrated that ICA may be a potential therapeutic agent for ovarian cancer treatment.

FBP1 promotes ovarian cancer development through the acceleration of cell cycle transition and metastasis.

Epithelial ovarian cancer (EOC) is the fifth most common malignancy in women, with a 5-year mortality of >70% in North America. As the symptoms are often not observed until the cancer has spread extensively, few women are diagnosed at an early stage of disease. Large-scale gene expression analyses have identified molecular subtypes within high-grade ovarian cancer with variable survival rates and drug resistance. The understanding of gene expression, the mechanisms underlying cancer processes and drug resistances have facilitated the development of targeted therapies. The far-upstream element (Fuse)-binding protein 1 (FBP1) is overexpressed in a number of malignancies such as hepatocellular carcinoma, and has been identified as an oncoprotein. In our early studies, FBP1 was demonstrated to physically interact with p53 and suppresses p53 transcription activity. In the present study, FBP1 expression increased as ovarian cancer developed. Among ovarian normal, adenoma and carcinoma tissues, the highest FBP1 expression was identified in carcinoma tissues. Furthermore FBP1 did not influence the apoptosis of ovarian carcinoma cells, yet enhanced cell cycle transition and metastasis. Therefore, it was hypothesized that FBP1 promotes ovarian cancer development through the acceleration of cell cycle transition and metastasis, and FBP1 is a novel potential biological marker for epithelial ovarian cancer diagnosis.

Knockdown of FUSE binding protein 1 enhances the sensitivity of epithelial ovarian cancer cells to carboplatin.

Epithelial ovarian cancer (EOC) affects almost 25,000 women annually and is the fifth most common malignancy in women in North America. A combination of surgery and cytotoxic chemotherapy may produce a favorable clinical response. The platinum-paclitaxel combination regimen is the chemotherapy gold-standard for advanced ovarian cancer, and carboplatin is one of the agents in this combination therapy. However, the majority of patients eventually experience a relapse due to the development of platinum resistance. FUSE binding protein 1 (FBP1) has been identified as an anti-apoptotic and pro-proliferative oncoprotein that is overexpressed in hepatocellular carcinoma. Its high expression is also associated with carboplatin resistance. In the present study, it was identified that the expression of FBP1 was significantly higher in EOC tissues than in normal epithelial ovarian or in epithelial ovarian adenoma tissue. FBP1 expression was significantly correlated with the grade of epithelial ovarian cancer. Carboplatin inhibited the expression of FBP1 in epithelial ovarian cancer cells and the knockdown of FBP1 enhanced the inhibition of cell viability and migration by carboplatin. In addition to FBP1, carboplatin also inhibited the expression of ß-catenin and matrix metalloproteinase (MMP)-9. Furthermore, the expression of ß-catenin and MMP-9 were lower in FBP1 knockdown cells compared with control EOC cells. FBP1 may thus serve a role in the regulation of the expression of ß-catenin and MMP-9; the inhibition of ß-catenin and MMP-9 by carboplatin may be mediated through the inhibition of FBP1. The inhibition of FBP1 expression by carboplatin may be a mechanism in the treatment of EOC by carboplatin.

CHD1L Promotes Neuronal Differentiation in Human Embryonic Stem Cells by Upregulating PAX6.

Chromodomain helicase DNA-binding protein 1-like gene (CHD1L) was initially isolated as a candidate oncogene in hepatocellular carcinoma, and it has been associated with many malignancies. Knockdown of Chd1l in zygote-stage mouse embryos resulted in developmental arrest, suggesting that Chd1l is required for mouse early development. However, the exact role of CHD1L in development, especially in humans, has not been reported. In this study, we found that overexpression of CHD1L in human embryonic cells (hESCs) upregulated the expression of ectoderm genes, especially PAX6. Furthermore, ectopic expression of CHD1L promoted hESCs to differentiate into neuroepithelium both in embryoid bodies and in directed neuronal differentiation. Knockdown of CHD1L significantly impaired neuroepithelial differentiation of hESCs. Interestingly, Chd1l colocalized with a PAX6-positive cell population and was highly expressed in the ventricular (germinal) zone of fetal mice. Taken together, these data suggest that CHD1L promotes neuronal differentiation of hESCs and may play an important role in nervous system development.