REX-1 Represses RASSF1a and Activates the MEK/ERK Pathway to Promote Tumorigenesis in Prostate Cancer.

Epigenetics play an important role in the pathogenesis of prostate cancer; it is urgent to investigate vital transcription factors in methylation regulation with the aim to develop novel treatment strategies targeting prostate cancer. As a member of the zinc finger protein family, REX-1 (reduced expression-1) is a transcription factor that has been reported to be closely linked to the development of several cancers. So far, the expression level and precise function of REX-1 in prostate cancer remain largely unknown. Here, we show that REX-1 was overexpressed in prostate cancer clinical tissues, and its expression level was closely correlated with patient prognosis. REX-1 affected prostate tumor growth in vivo by MEK/ERK phosphorylation. Mechanistic studies indicated that REX-1 recruited DNMT3b (DNA methyltransferase 3b), inhibited the transcription of RASSF1a (RAS association domain family 1a), and further modulated methylation of RASSF1a promoter. Intervention of the REX-1/DNMT3b/RASSF1a axis may shed light on the development of novel therapeutic approaches for prostate cancer treatment. IMPLICATIONS: REX1 overexpression recruits DNMT3b and downregulates RASSF1a by promoter methylation, suggesting that epigenetic intervention may contribute to prostate cancer treatment.

Case report: Analysis of BRCA1 and BRCA2 gene mutations in a hereditary ovarian cancer family.

OBJECTIVE: Breast cancer susceptibility gene 1/2 (BRCA1/2) is the most important susceptibility gene associated with hereditary ovarian cancer (HOC). We aimed to screen BRAC1 and BRAC2 gene mutations in a member of a hereditary ovarian cancer family in China, and to analyze the structure and function of the mutant protein. METHODS: A typical HOC family was selected. Blood samples and pathological tissue samples were taken from the female members of the family. Blood samples from two patients with sporadic ovaries of the same pathological type were taken as a control group. After RNA extraction, PCR amplification was applied and the PCR products were directly sequenced and aligned, prediction and analysis of protein structure and molecular conformation that may be caused by BRCA1/2 mutation. RESULTS: The whole gene analysis of BRCA1 and BRCA2 in ovarian cancer patients in the family showed that there were 8 mutations in BRCA1 whole gene sequencing, including 3 nonsense mutations (2314C>T, 2543T>C, 4540T>C); two mutations have been recorded, which are associated with cervical cancer (2844C>T) and endometriosis (3345A>G); three newly discovered mutations (3780A>G, 5069A>G, 3326A>T). Among them, 3780A>G and 5069A>G caused amino acid changes, while 3326A>T mutation caused Arg mutation to stop codon. A total of 7 mutations were detected in BRCA2 whole-genome sequencing, including 5 non-significant mutations (3623A>G, 4034T>C, 4790A>G, 6740G>C, 7469A>G); one no-record mutation (1716T>A), and 1 recorded mutation (1342A>C), which was associated with breast cancer and ovarian cancer. BRCA1 (3326A>T) and BRCA2 (1342A>C) mutations were co-existing in patients (II1, II3, and II5) identified as serous adenocarcinoma grade II. Two cases of ovarian serous cystadenocarcinoma with no history of family tumors were normalized for BRCA1/2 gene sequencing. In the gene detection of III generation female, four females with BRCA2 (1342A>C) mutation were found, and one of them also carried the BRCA1 (3326A>T) mutation, who can be considered a high-risk group of HOC in this family. Online protein structure predictions revealed that BRCA1 (3326A>T) mutations mutated AGA at this site to TGA resulting in a translated Arg (arginine) mutation as a stop codon, while BRCA2 (1342A>C) mutated AAT at this site to CAT resulting in a translated Asn mutation to His. CONCLUSION: The BRCA1 (3326A>T) and BRCA2 (1342A>C) were detected in the HOC family, which may be the susceptibility gene of the family's HOC. The BRCA1/2 gene screening may be possible to obtain high-risk populations in this family.

Relationship between autoimmune liver disease and autoimmune thyroid disease: a cross-sectional study.

Background: A high prevalence of autoimmune thyroid disease (AITD) has been observed in patients with autoimmune liver disease (AILD); however, data on the clinical relationship between AILD and AITD remain scant. We aimed to evaluate the relationship between AILD and AITD.Methods: We performed a retrospective study using medical records from 324 patients with AILD, 113 of whom had concurrent AITD.Results: Patients with autoimmune hepatitis (AIH) were more likely to develop AITD (45.8%), followed by autoimmune hepatitis-primary biliary cholangitis overlap syndrome (AIH-PBC OS) (39.5%) and PBC (22.6%). Patients with concurrent AILD and AITD showed higher levels of immunoglobulin G (IgG) (21.5 g/L vs 16.3 g/L, p < .0001) and gamma globulin (γ-globulin) (27.1% vs 21.9%, p < .0001). IgG was positively correlated with thyroid antibodies [thymoglobulin antibody (TGAb) and thyroperoxidase antibody (TPOAb)] (r = 0.396, 0.322; p < .0001, p = .002, respectively). TPOAb positivity was highest in PBC patients with concurrent AITD (83.9%). Patients with concurrent PBC and AITD were significantly older than those with PBC alone (p = .0004). Patients with concurrent AIH and AITD had a higher homogenous nuclear pattern of antinuclear antibody positivity compared to those with AIH alone (p = .019). Thyroid dysfunction in AILD patients with concurrent AITD was principally characterized by Hashimoto's thyroiditis (65.5%), and diffuse lesions were mainly found by thyroid ultrasound (53.1%).Conclusions: The high incidence of AILD concomitant with AITD, the higher levels of serum IgG and γ-globulin, and the strong correlation between thyroid antibodies and IgG suggest that close screening for AITD and accurate physical examinations should be performed for all patients with AILD.

Hypoxia-induced PLOD2 regulates invasion and epithelial-mesenchymal transition in endometrial carcinoma cells.

BACKGROUND: Procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2) was induced in hypoxia and participated in cancer development. However, the role of PLOD2 in endometrial carcinoma remains unclear. OBJECTIVE: To explore the influences and regulation mechanism of PLOD2 in endometrial carcinoma under hypoxic condition. METHODS: The small interfering RNA (siRNA) targeting to PLOD2 and pcDNA3.1-PLPD2 were transfected to endometrial carcinoma cells to alter PLOD2 expression. Cell proliferation ability was determined by colony formation assay. Wound healing assay used to detect cell migration ability. Transwell invasion assay was used to detect cell invasion ability. RESULTS: PLOD2 and Hypoxia-inducible factor-1α (HIF-1α) were induced by hypoxia. Down-regulation of PLOD2 did not affect endometrial carcinoma cell proliferation ability, while inhibited cell migration, invasion under hypoxic condition. Besides, down-regulation of PLOD2 increased the levels of γ-catenin and E-cadherin and decreased levels of Fibronectin and Snail under hypoxic condition. Down-regulation of PLOD2 also inactivated Src and phosphoinositide 3-kinase (PI3K)/ protein kinase B (Akt) signaling under hypoxic condition. The promoting effects of PLOD2 overexpression on migration, invasion and epithelial-mesenchymal transition (EMT) of endometrial carcinoma cells were reversed by Akt inhibitor (MK2206) under hypoxic condition. CONCLUSION: PLOD2 expression was increased in endometrial carcinoma cells under hypoxic condition. PLOD2 modulated migration, invasion, and EMT of endometrial carcinoma cells via PI3K/Akt signaling. PLOD2 may be a potential therapeutic target for endometrial carcinoma.

Naringin inhibits ovarian tumor growth by promoting apoptosis: An in vivo study.

The aim of the present study was to investigate the antitumor activities of naringin in ovarian cancer, and to assess the underlying mechanisms. Ovarian tumor cells were implanted into nude mice to produce ovarian tumors in vivo. The mice were divided into six groups: Control, low dose naringin [0.5 mg/kg, intraperitoneal (i.p.)], middle dose naringin (1 mg/kg, i.p.), high dose naringin (2 mg/kg, i.p.), positive control (cisplatin, 2 mg/kg, i.p.) and a combination of cisplatin and naringin (both 2 mg/kg). Following administration of naringin and/or cisplatin, the tumor size and weight were measured. Apoptosis of tumor cells was detected using a terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Apoptosis-associated gene expression was detected using reverse transcription-polymerase chain reaction and immunohistochemistry. In the range of 0.5-2 mg/kg, naringin dose-dependently inhibited tumor growth, as demonstrated by a decrease in tumor size and weight. Naringin promoted apoptosis of the ovarian tumor cells. Additionally, naringin reduced the expression of B-cell lymphoma (Bcl)-2, Bcl-extra large (Bcl-xL), cyclin D1, c-Myc and survivin, while it increased the expression of caspase-3 and caspase-7. The data demonstrated that naringin inhibited ovarian tumor growth in vivo. Its mechanisms may be associated with caspase-7-, caspase-3-, Bcl-2- and Bcl-xL-mediated apoptosis. Nevertheless, the clinical application of naringin in the treatment of ovarian cancer requires further study.

MicroRNA-381 inhibits cell proliferation and invasion in endometrial carcinoma by targeting the IGF-1R.

Endometrial carcinoma (EC) is the sixth most common type of malignant tumor occurring in females. MicroRNAs (miRNAs) serve as oncogenes or tumor suppressors in human cancer and play important roles in tumorigenesis, and tumor development by regulating various processes. Thus, further investigation into miRNAs involved in EC formation and progression may aid in developing effective therapeutic strategies for patients with this disease. miRNA­381 (miR­381) is aberrantly expressed in multiple types of human cancer. However, the expression pattern, biological roles and underlying mechanisms of miR­381 in EC are poorly understood. In the present study, the results showed that miR­381 was downregulated in EC tissues and cell lines. Decreased miR­381 expression correlated with the International Federation of Gynecology and Obstetrics stage, lymph nodes metastasis and myometrial invasion of EC. The ectopic expression of miR­381 significantly inhibited the proliferation and invasion of EC cells. Through a series of experiments, the insulin­like growth factor receptor 1 (IGF­1R) was identified as a novel direct target of miR­381 in EC. Furthermore, IGF­1R was highly expressed in EC tissues and inversely correlated with miR­381 levels. IGF­1R overexpression partially abrogated the tumor­suppressive effects of miR­381 on the proliferation and invasion of EC cells. miR­381 targeted IGF­1R to inactivate the protein kinase B (AKT) and extracellular signal­regulated kinase (ERK) signaling pathways in EC. These results suggest that miR­381 acts as a tumor suppressor in EC by directly targeting IGF­1R, and indirectly regulating the AKT and ERK signaling pathways. Thus, miR­381 should be investigated as a prognostic biomarker and novel therapeutic target for the treatment of patients with EC.

Management of intrauterine adhesions: a novel intrauterine device.

Intrauterine adhesions (IUAs) are a rare but significant cause of menstrual disturbance and infertility. Most cases are caused by uterine instrumentation. Several methods have been used to prevent IUAs in the past, which can be divided into two groups: pharmacological treatment and physical barrier. However, even with the liberal use of ancillary treatments to minimize reformation of adhesions, IUAs have a high rate of recurrence. Furthermore, medical literature of the last decades has only dedicated great attention to the restoration of normal anatomy in the uterine cavity, but not on the function of the endometrium. When the lesion of the endometrium is severe, especially intrauterine fibrosis, few basal layer is left which contains plenty stem cells to regenerate functional endometrium. Loss of endometrial stem cells directly causes the proliferation of fibrous tissue and subsequent synechiae. None of current treatments can compensate the defect of loss of stem cells. On the basis of existing researches, a novel intrauterine device (IUD) is recommended in this article. The new IUD consists of a light frame which contains two isolated drug-releasing system, one for estrogen and the other for cytokines to promote regeneration of endometrium such as growth factors, and a membrane in the middle of the frame which is also the carrier of endometrium stem cell. This device not only helps to preserve the original anatomy of the uterine cavity, but also to recover the function of endometrium. Experimental and clinical studies are now needed to testify the efficiency of the novel IUD in the prevention of IUAs. If there is a marked reduction in the IUAs and/or improvement of pregnancy success in the case group compared with the control group, our hypothesis will be confirmed.

Protection of CHO cells by transfer of survivin driven by ovarian-specific promoter OSP-2.

Chemotherapy is the major therapy for cancer in clinic. However, chemotherapeutic agents can harm the other tissues/organs besides cancer. Thus, there are great interests in protecting the innocents by the transfer of protective genes. There are two problems to be solved, one is the selection of protective genes and the other is the orientation of the exotic genes. Recent researches demonstrated that the principal mechanism of chemotherapeutics was through apoptosis. Hereby, introduction of anti-apoptosis genes might interrupt the processes of apoptosis to avoid side effect from chemotherapeutics. On the other hand, tissue-specific promoters, which control gene expression in a tissue-specific manner, might be an alternative tool to guarantee the location of target genes. In this research, we applied gene therapy to chemoprotection using anti-apoptosis gene survivin and ovarian-specific promoter OSP-2. The results showed that OSP-2 could specifically drive the expression of survivin in ovarian cells and survivin could protect cells via inhibiting apoptosis. This might put a light on the future of chemoprotective gene therapy.

Cloning and transcriptional activity of a novel ovarian-specific promoter from rat retrovirus-like elements.

The long terminal repeats (LTRs) are the control centers for retrovirus gene expression, which possess all of the requisite signals. It has been proved that the LTRs of Moloney murine leukemia virus (MoMLV) could constitutively activate genes in diverse cell types. Recently, a retrovirus-like element, OSP-1 (ovarian-specific promoter 1), was extracted from rat ovary according to the LTRs of MoMLV, whose name was derived from the fact of ovarian-specific transcription. It was reasonable to speculate that the tissue-specificity was acquired through mutations and that there should be abound other mutants, active or inactive. In the present study, we isolated several homologous sequences to OSP-1 and detected their function. Consequently, one of them could also drive target gene expression specifically to ovarian cell lines and was named OSP-2 which shared 98% similarity to OSP-1. On the other hand, we picked up other two closest sequences and proved them inactive, which was 97% and 95% similar to OSP-1, respectively. Sequence analysis revealed the different mutations around/within the binding sites of transcriptional factors that might play important roles in tissue-specificity. In summary, we extracted a novel ovarian-specific promoter as well as other nonfunctional mutants, which in part shed light on the study of ovarian-specific transcription. In addition, it also provided a new tool in cancer gene therapy and to create transgenic animals.