Search

Background: Recent studies have suggested that estrogen (E2) plays an important role in epithelial ovarian cancer (EOC). However, the mechanism of E2 in ovarian cancers is unclear. The purpose of this study was to investigate the effect of E2 on ovarian cancers and illuminate the mechanism of E2 in promote ovarian cancers proliferation. Results: We demonstrated that E2 stimulated the proliferation and invasion of ovarian cancer cells. In this study, ovarian cancer specimens were also analyzed for transient receptor potential channel C3 (TRPC3) expression; TRPC3 expression levels were higher in ovarian cancer samples than in normal ovarian tissue samples. Previous studies have shown that TRPC3 contributes to the progression of human ovarian cancer. In this study, we further investigated the interaction between E2 and TRPC3. We found that E2 stimulation enhanced the expression of TRPC3 at both the mRNA and protein levels. E2 stimulation enhanced the influx of Ca2+. Moreover, siRNA-mediated silencing of TRPC3 expression inhibited the ability of E2 to stimulate the influx of Ca2+. Conclusions: In conclusion, TRPC3 plays a significant role in the stimulatory activity of E2 and could be a therapeutic target for the treatment of EOC. Furthermore, this study elucidates the molecular mechanism by which E2 promotes the proliferation and migration of EOC cells. [ABSTRACT FROM AUTHOR]

Paclitaxel resistance becomes common in patients with aggressive ovarian cancer and results in recurrence after conventional therapy. Galectin-3 is a multifunctional lectin associated with cell migration, cell proliferation, cell adhesion, and cell-cell interaction in tumor cells. Whether circulating galectin-3 is involved in paclitaxel resistance in ovarian cancer remains unknown. The current study investigated the effect of galectin-3 on toll-like receptor 4 (TLR4) signaling and thus paclitaxel resistance. With blood and cancer tissue samples obtained from 102 patients, we identified associations between serum galectin-3 level or TLR4 expression and paclitaxel resistance phenotype. In vitro, treatment with exogenous galectin-3 restored cell survival and migration of SKOV-3 and ES-2 cells was decreased by galectin-3 silencing and paclitaxel treatment. Furthermore, exogenous galectin-3 boosted expression of TLR4, MyD88, and p-p65, as well as interleukin (IL)-6, IL-8, and vascular endothelial growth factor (VEGF) release induced by paclitaxel. Moreover, galectin-3 inhibited the interaction between TLR4 and caveolin-1 (Cav-1) in SKOV-3 and ES-2 cells. In addition, overexpression of Cav-1 dampened the expression of MyD88 and p-p65 stimulated by galectin-3 and enhanced apoptosis in SKOV-3 cells under paclitaxel exposure. In summary, our study elucidated that exogenous galectin-3 might induce paclitaxel resistance through TLR4 signaling activation by inhibiting TLR4-Cav-1 interaction, revealing a novel insight into paclitaxel resistance induction. [ABSTRACT FROM AUTHOR]

Apurinic/apyrimidinic endonuclease 1 (APE1) plays an essential role in the base excision repair pathway. Recent studies have shown that APE1 polymorphisms are associated with an increased risk for many types of cancers. This study investigated the association between APE1 polymorphisms and the susceptibility of ovarian cancer.A case-control study was performed on 124 patients with ovarian cancer and 141 controls. We genotyped the rs1760944 and rs1130409 polymorphisms and assessed their associations with the risk for ovarian cancer.The rs1130409 polymorphism was significantly associated with a risk for ovarian cancer. The TG/GG genotype and the G allele were associated with a decreased risk for ovarian cancer (adjusted odds ratio [aOR], 0.495; 95% confidence interval [CI], 0.267-0.920 for TG vs TT; aOR, 0.263; 95% CI, 0.132-0.521 for GG vs TT; aOR, 0.486; 95% CI, 0.344-0.0.688 for the G allele vs the T allele). In the stratified analyses, we found that when comparing the TG/GG genotype versus the TT genotype, the lower risk was more evident in subgroups of patients 50 years or older (aOR, 0.753; 95% CI, 0.604-0.938), patients with menarche age of 15 years or older (aOR, 0.722; 95% CI, 0.573-0.910), patients with gravidity of 3 or more times (aOR, 0.732; 95% CI, 0.587-0.912), and postmenopausal women (aOR, 0.763; 95% CI, 0.615-0.947). Meanwhile, the rs1760944 polymorphism was not found to be associated with a risk for ovarian cancer. However, by haplotype analysis, we found that the T-G and G-G haplotypes were associated with a decreased risk for ovarian cancer.Our results suggest that in a Han Chinese population, the APE1 rs1130409 polymorphism may correlate with ovarian cancer susceptibility. [ABSTRACT FROM AUTHOR]

Ovarian cancer is a lethal malignant tumour characterised by activated invasion, distant metastasis, anti-cancer drug resistance, angiogenesis and metabolism. CD147, an extracellular matrix metalloproteinase inducer, is overexpressed in most ovarian tumours and plays an important role in the progression of ovarian cancer and other malignant tumours. However, the factor(s) initiating this overexpression is unknown. Because of rapid reproduction and their hypoxic microenvironment, malignant tumours use glycolysis for energy, and lactic acid produced is harmful to the cells. For survival, excessive lactate needs to be transported by monocarboxylate transporters (MCTs). Functioning of MCT1 and MCT4 require the ancillary of CD147. The gene for CD147 possesses two hypoxia-inducible factors binding sites in its 3′-flank. It is logical to postulate that the hypoxic microenvironment is a major initiator of the overexpression of CD147, thus conferring on ovarian cancers their malignant properties. A model that can represent spontaneous ovarian cancer is necessary to verify this hypothesis. [ABSTRACT FROM AUTHOR]

Ovarian cancer, a gynecological malignancy, is the most common cause of death in older women worldwide. The overall 5-year survival of ovarian cancer patients is only 20% because of late diagnosis, as well as distant metastasis and multidrug resistance. Therefore, predictive and prognostic markers are urgently required for the early diagnosis of ovarian cancer. CD147, an extracellular matrix metalloproteinase inducer, is overexpressed in ovarian cancers. Current knowledge suggests that CD147 is associated with the survival and progression of ovarian cancer, and is considered as a biomarker of poor outcome. Here, we specifically review the roles of CD147 in ovarian cancer progression and discuss the diagnostic and prognostic value of CD147 in patients with ovarian cancer. CD147 promotes ovarian cancer progression by its involvement in every facet of malignancy, including invasion, metastasis, survival, angiogenesis, and drug resistance. Although it is not fully confirmed, the combination of CD147 with other biomarkers might be of diagnostic value. [ABSTRACT FROM AUTHOR]

The vascular dysfunction of ovarian cancer (OC) contributes to the chemotherapeutic resistance. In this study, we aimed to explore whether exosome-mediated angiogenesis blocking could improve the chemotherapy sensitivity via vascular normalization. Exosomes were armed with RGD on the surface by fusing Lamp2b. Candidate miRNAs related to tumor angiogenesis was detected by qRT-PCR. RGD-modified exosomes were loaded with miRNAs via electroporation. The therapeutic effects of the exosomes on angiogenesis, vascular normalization, and chemotherapy sensitivity were systemically analyzed in the xenograft model. RGD-modified exosomes were relatively enriched in the tumor mass, both the tumor cell and the endothelial cells. Among the miRNA candidates, miR-484 was found down-regulated in both the cancer cells and the angiogenic endothelial cells. In vivo xenograft model experiment revealed that injection of RGD-modified exosomes loaded with miR-484 induced vessel normalization and in turn sensitized the cancer cells to chemotherapy induced apoptosis. Mechanistically, miR-484 simultaneously inhibited the expression of VEGF-A from the cancer cells and the corresponding receptors in the endothelial cells. Targeted delivery of miR-484 via RGD-modified exosomes improves the vascular normalization, sensitizes the cancer to chemotherapy, and prolongs the survival time of tumor-bearing mice after chemotherapy, opening an avenue for the clinical management of chemotherapy resistance. [ABSTRACT FROM AUTHOR]

Salt-inducible kinase 2 (SIK2), which belongs to the AMP-activated protein kinase family, modulates various biological functions including fatty acid oxidation. However, the role of SIK2 in glucose metabolism reprogramming remains unclear in ovarian cancer (OC) cells. Here, we found that SIK2 significantly enhanced the Warburg effect of OC cells mainly through two mechanisms. On the one hand, SIK2 upregulated the expression of HIF-1α by activating the PI3K/AKT signaling pathway, which directly upregulated the transcription of major glycolytic genes to promote glycolysis. On the other hand, SIK2 promoted mitochondrial fission through phosphorylation of Drp1 at Ser616 site, which inhibited the mitochondrial oxidative phosphorylation. In addition, SIK2 promoted growth and metastasis of OC cells by promoting cell proliferation and inhibiting cell apoptosis, as well as enhancing the epithelial-mesenchymal transition. Moreover, the SIK2-mediated reprogramming of glucose metabolism played a critical role in growth and metastasis of OC cells. Collectively, our findings demonstrate that SIK2 is a crucial regulator of glucose metabolism in OC cells through activation of PI3K/AKT/HIF-1α pathway and Drp1 phosphorylation-mediated mitochondrial fission, which plays a critical oncogenic role in OC cells. [ABSTRACT FROM AUTHOR]

Ovarian cancer (OC) is a common malignant tumor in gynecology. LMNB1 is an important component of the nuclear skeleton. The expression of LMNB1 in ovarian cancer is significantly higher than that in normal tissues, but its role in tumor still needs comprehensive investigation. In this study, we overexpressed and knocked down LMNB1 in ovarian cancer cells and explore the effect of LMNB1 on the cell proliferation, migration and the underlying mechanism. We analyzed the expression levels of LMNB1 in ovarian cancer and their clinical relevance by using bioinformatics methods, qRT-PCR, Western blot and immunohistochemistry. To state the effect and mechanism of LMNB1 on OC in vitro and in vivo, we performed mouse xenograft studies, CCK8, cloning formation, Edu incorporation, wound healing, transwell and flow cytometry assay in stable LMNB1 knockdown OC cells, following by RNA-seq. Overexpression of LMNB1 indicates the progression of OC. LMNB1 knockdown inhibited the proliferation and migration of OC cells by suppressing the FGF1-mediated PI3K-Akt signaling pathway. Our study shows LMNB1 as a novel prognostic factor and therapeutic target in OC. [ABSTRACT FROM AUTHOR]

Abstract: Intercellular adhesion molecule-1 (ICAM-1, encoded by ICAM-1) is implicated in tumorigenesis and tumor progression. ICAM-1 modulates the susceptibility to several types of cancer and the disease prognosis; however, its role in epithelial ovarian cancer (EOC) is unclear. Here, we evaluate single nucleotide polymorphisms (SNPs) in ICAM-1 as predictors of EOC risk and prognosis. Six ICAM-1 polymorphisms were genotyped in 408 patients with EOC and 520 controls using the MassARRAY system. The ICAM-1 mRNA levels in 89 EOC tissues and 35 normal ovarian tissues were examined using quantitative PCR. The ICAM-1 rs5498 G allele was associated with increased tumor grade (OR=2.650) and EOC risk (OR=1.405). This risk was more evident in females who had first-degree relatives (FDRs) with a tumor (OR=3.475) or who experienced early menarche (OR=2.774). The ICAM-1 expression in the cancerous tissue was elevated compared with that of normal ovarian tissues (p <0.0001), and it was associated with an rs5498 genotype (p =0.0002). ICAM-1 SNPs did not significantly predict the overall EOC survival (p >0.05). However, the rs5498 G allele correlated with EOC survival time in patients whose FDRs suffered from a tumor (p =0.001). ICAM-1 rs5498 likely confers a high risk for EOC in G allele carriers accompanied by up-regulation of ICAM-1 expression during carcinogenesis. The combination of ICAM-1 rs5498 and tumor history predicts the EOC prognosis. [Copyright &y& Elsevier]

Abstract: Objective: The CASP8 gene plays a central role in the apoptotic pathway and is therefore a plausible cancer susceptibility gene. However, the precise role of the CASP8 gene in epithelial ovarian cancer carcinogenesis is unclear. Therefore, we analyzed the correlation between single nucleotide polymorphisms (SNPs) and haplotypes in CASP8 and the risk and clinical characteristics of epithelial ovarian cancer (EOC) in the Chinese population. Subjects and methods: Eight tag SNPs were identified using the MassARRAY system to genotype 37 genetic polymorphisms around and in the CASP8 gene in 100 unrelated, healthy females. Then, a case-control study of 218 EOC patients and 285 controls who were matched on residence, age and race was conducted using these 8 tag SNPs. Results: The risk of developing EOC was significantly decreased in association with CASP8 rs3834129 ins>del (odds ratio (OR)del/del =0.129, 95% confidence interval (95% CI): 0.038–0.439; ORins/del =0.769, 95% CI, 0.534–1.108), rs3769827 T>C (ORC/C =0.187, 95% CI: 0.070–0.500; ORT/C =0.729, 95% CI: 0.505–1.052), rs6704688 C>T (ORT/T =0.344, 95% CI, 0.168–0.707; ORC/T =0.802, 95% CI, 0.552–1.166), and with the del-C-T haplotype of these 3 SNPs (OR=0.615, 95% CI: 0.453–0.8363). Moreover, a notably later onset was significantly associated with the rs3834129 ins/del+del/del and the rs3769827 T/C+C/C genotypes (p<0.0001). Conclusions: Genetic variants of the CASP8 gene protect against EOC carcinogenesis and delay the age of EOC onset. Furthermore, these protective effects may be due to the dysfunctional expression of caspase-8 caused by the −652 6N del variant in the promoter. [Copyright &y& Elsevier]

Abstract: Overexpression of extracellular matrix metalloproteinase inducer (EMMPRIN or CD147), a member of the immunoglobulin family and a glycoprotein enriched on the surface of tumor cells, promotes invasion, metastasis, growth and survival of malignant cells, and confers resistance to some chemotherapeutic drugs. Here, we used a human U6 promoter-driven DNA template approach to induce short hairpin RNA (shRNA)-triggered RNA interference (RNAi) to block CD147 gene expression in the human ovarian cancer cell line HO-8910pm. Knockdown of CD147 by shRNA resulted in decrease of the HO-8910pm invasion activity in vitro and tumorigenicity in nude mice. The suppression of CD147 expression also sensitized cells to be more sensitive to paclitaxel. These results suggested that CD147 was an ovarian cancer-related gene and CD147 might be a potential target for therapeutic anti-cancer drugs. [Copyright &y& Elsevier]

Immune escape is the main cause of the low response rate to immunotherapy for cancer, including ovarian cancer. Growth differentiation factor-15 (GDF-15) inhibits immune cell function. However, only few reports described the mechanism. Therefore, the aim of this study was to investigate the mechanism of immune escape regulated by GDF-15 in ovarian cancer. Ovarian cancer patients and healthy women were enrolled in this study. Immunohistochemistry and ELISA were performed to measure GDF-15 expression. Immunoprecipitation combined with mass spectrometry, surface plasmon resonance, and co-immunoprecipitation assay were used to evaluate the interaction between GDF-15 and the surface molecules of DCs. Immunofluorescence analysis, flow cytometry and transwell assay were used to evaluate additional effects of GDF-15 on DCs. The results showed that GDF-15 expression was higher in the ovarian cancer patients compared to that in the healthy women. The TIMER algorithm revealed that highly GDF-15 expression is associated with immune DC infiltration in immunoreactive high-grade serous carcinoma. A further study showed that GDF-15 suppressed DCs maturation, as well as IL-12p40 and TNF-α secretion, the length and number of protrusions and the migration. More importantly, CD44 in the surface of DCs interacted with GDF-15. The overexpression of CD44 in DCs resulted in the suppression of the inhibitory effect of GDF-15 on the length and number of DC synapses. In DCs overexpressing CD44 the inhibition of GDF-15 on the expression of CD11c, CD83 and CD86 was decreased, while in DCs with a knockdown of CD44 the inhibition was further enhanced. Knockdown of CD44 in DCs enhanced the inhibitory effect of GDF-15 on DC migration, while the overexpression of CD44 inhibited the inhibitory effect of GDF-15 on DC migration. In conclusion, the present study suggested that GDF-15 might facilitate ovarian cancer immune escape by interacting with CD44 in DCs to inhibit their function. [Display omitted] [ABSTRACT FROM AUTHOR]