Elevated circRNAs circ_0000745, circ_0001531 and circ_0001640 in human whole blood: Potential novel diagnostic biomarkers for breast cancer.

BACKGROUND AND OBJECTIVES: Increasing studies have shown that circular RNAs (circRNAs) have great diagnostic potential in cancer. Here, we examined whether the blood circRNAs could be promising candidates as diagnostic biomarkers in breast cancer. METHODS: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed to detect levels of five circRNAs (circ_0000501, circ_0000745, circ_0001531, circ_0001640 and circ_0001978) in 129 patients with breast cancer, 19 patients with benign breast tumor and 13 healthy controls. The diagnostic accuracy of circRNAs was assessed using the receiver operating characteristic (ROC) curve. A circRNA-miRNA-mRNA network was constructed based on bioinformatic analysis. RESULTS: QRT-PCR validated that circ_0000745, circ_0001531 and circ_0001640 were upregulated in breast cancer, compared with benign tumor and healthy control. ROC curve analysis revealed that circ_0000745, circ_0001531 and circ_0001640 had good diagnostic potential. Notably, a signature comprising the three circRNAs showed better diagnostic potential, with the area under curve (AUC) of 0.9130 (P < 0.0001). And a circRNA-miRNA-mRNA network revealed that the circRNAs could participate in complex regulated network and thus involve in cancer development and progression. CONCLUSIONS: Taken together, our findings support the potential of circ_0000745, circ_0001531, circ_0001640 and the three-circRNA signature as biomarkers for breast cancer diagnosis.

Tumor suppressor OTUD3 induces growth inhibition and apoptosis by directly deubiquitinating and stabilizing p53 in invasive breast carcinoma cells.

BACKGROUND: P53 pathway inactivation plays an important role in the process of breast cancer tumorigenesis. Post-translational protein modification abnormalities have been confirmed to be an important mechanism underlying inactivation of p53. Numerous deubiquitinating enzymes are aberrantly expressed in breast cancer, and a few deubiquitination enzymes can deubiquitinate and stabilize p53. Here, we report that ovarian tumor (OTU) deubiquitinase 3 (OTUD3) is a deubiquitylase of p53 in breast carcinoma (BC). METHODS: Correlations between the mRNA expression levels of OTUD3, TP53 and PTEN and the prognosis of BC were assessed with the Kaplan-Meier Plotter tool. OTUD3 protein expression in 80 pairs of specimens in our cohort was examined by immunohistochemistry and western blotting. The relationship among OTUD3, p53, and p21 proteins was analyzed. Half-life analysis and ubiquitylation assay were performed to elucidate the molecular mechanism by which OTUD3 stabilizes p53. The interaction between OTUD3 and p53 in BC cells was verified by a co-immunoprecipitation assay and GST pulldown experiments. MTS assay for proliferation detection, detection of apoptosis induced by cisplatin and colony formation assay were employed to investigate the functional effects of OTUD3 on breast cancer cells. RESULTS: OTUD3 downregulation is correlated with a poor prognosis in BC patients. OTUD3 expression is decreased in breast cancer tissues and not associated with the histological grade. OTUD3 also inhibits cell proliferation and clone formation and increases the sensitivity of BC cells to apoptosis induced by chemotherapy drugs. Reduced OTUD3 expression accompanied by decreased p53 abundance is correlated with human breast cancer progression. Ectopic expression of wild-type OTUD3, but not its catalytically inactive mutant, stabilizes and activates p53. Mechanistically, OTUD3 interacts directly with p53 through the amino-terminal OTU region. Finally, OTUD3 protects p53 from murine double minute 2 (Mdm2)-mediated ubiquitination and degradation, enabling the deubiquitination of p53 in BC cells. CONCLUSIONS: In summary, we found that OTUD3 may be a potential therapeutic target for restoring p53 function in breast cancer cells and suggest that the OTUD3-p53 signaling axis may play a critical role in tumor suppression.

The Novel Transcription Factor CREB3L4 Contributes to the Progression of Human Breast Carcinoma.

Breast carcinoma(BC)is the most common cancer type among females globally. Understanding the molecular pathways that trigger the development of BC is crucial for both prevention and treatment. As such, the role of transcription factors (TFs) in the development of BC is a focal point in this field. CREB3s play a critical role in initiating the unfolded protein response (UPR); however, the role of CREB3 family members in breast cancer development remains largely unknown. Here, we mined the ONCOMINE database for the transcriptional data of CREB3s in patients with BC. Then, the regulatory functions of a novel TF, CREB3L4, were investigated. CREB3L4 knockdown in MDA-MB-231 and MCF-7 cells suppressed proliferation and promoted apoptosis and cell cycle arrest. ChIP assays confirmed that CREB3L4 can directly bind to the PCNA promoter region, suggesting that the PCNA protein may be functionally downstream of CREB3L4. Additionally, the expression level of CREB3L4 was assessed using our cohort. CREB3L4 is upregulated in breast cancer tissues and is significantly associated with histological grade and tumour size (P = 0.001 and P < 0.001, respectively). Furthermore, PCNA expression was upregulated in breast cancer tissues and positively correlated with CREB3L4. In summary, CREB3L4 may play an important role in the progression of human BC and may serve as a therapeutic target.

Human papilloma viruses (HPVs) no co-existence in breast cancer and cervical cells in the same patient.

High-risk HPVs were detected in both breast cancer tissues and cervical cells from 56 breast cancer patients. The results suggested that HPV infection did not coexist in breast and cervical tissues. HPV infection of the breast cancer tissue is more likely to happen in patients without cervical infection.

The parasympathetic supply to the distal colon-one marker for precisely locating the posterior dissection plane in the operation of TME.

BACKGROUND: It is important for surgeons to locate the reliable surgical planes in the operation of total mesorectal excision (TME); we observe the parasympathetic nerve to the distal colon can be served as one of useful markers for precisely locating the posterior dissection plane in TME. MATERIALS AND METHODS: From October 2006 to January 2008, 26 patients underwent TME for rectal cancer. The dissections of the parasympathetic nerves to the distal colon were performed and the relationship of these nerves to the prehypogastric nerve fascia was observed. RESULTS: Some parasympathetic nerves ran upwards and lay anteromedial to the hypogastric nerves. In the avascular space between prehypogastric nerve fascia and the fascia propria of the rectum, the prehypogastric nerve fascia enveloped parasymphathetic nerve up to the fascia propria of rectum. CONCLUSIONS: The parasympathetic nerve to the distal colon is evident between the fascia propria of the rectum and the prehypogastric nerve fascia. As the precise dissection plane of TME lay between the fascia propria of the rectum and the prehypogastric nerve fascia, these nerves could be served as useful marker for precisely locating the posterior dissection plane in TME.

Ileal transposition controls diabetes as well as modified duodenal jejunal bypass with better lipid lowering in a nonobese rat model of type II diabetes by increasing GLP-1.

OBJECTIVE: Modified duodenal jejunal bypass (MDJB) and ileal transposition (IT) were compared as surgeries for glucose control. Initial conclusions might be formed with respect to the possibility of (1) whether duodenal exclusion is essential for the control of diabetes and (2) application as a low morbid procedure. SUMMARY BACKGROUND DATA: IT, MDJB, sham-IT, and sham-MDJB procedures were performed on 10- to 12-week-old Goto-Kakizaki (GK) rats, nonobese animals who spontaneously develop type 2 diabetes. Rats were observed for 24 weeks after surgery. Glucose, insulin, glucagon-like peptide-1 (GLP-1), glucose tolerance, insulin sensitivity, cholesterol, triglycerides, and free fatty acid levels were measured. RESULTS: MDJB and IT rats, when compared with sham-operated rats, showed reduced blood-glucose levels (P < 0.001); but IT- and MDJB did not differ from one another (P < 0.05). Compared with sham-operated rats, IT- and MDJB rats showed increased GLP-1 secretion (P < 0.01), with a more rapid and higher secretion in IT operated than in MDJB rats (P < 0.05). After 6 months, sham-operated rats weighed more than IT or MDJB rats (P < 0.01), but the weights of IT- and MDJB rats were similar to one another (P > 0.05). In terms of both operative time (P < 0.001) and postoperative recovery time (P < 0.001), MDJB took longer than did IT. CONCLUSION: In nonobese spontaneously diabetic rats, IT is equivalent to MDJB in terms of glucose control and weight secondary to significant increases of GLP-1. IT is faster to perform and yields a shorter recovery period than does MDJB.

[Status of estrogen receptor affects the drug sensitivity of drug-resistant MCF-7/Adr human breast cancer cells to droloxifene and Adriamycin].

BACKGROUND & OBJECTIVE: Loss or decreased expression of estrogen receptor (ER) and decreased growth rate regularly occur in drug-resistant breast cancer cells. This study was designed to investigate the effect of estrogen receptor status on the drug resistance to droloxifene (Dro) and Adriamycin (Adr) of drug-resistant MCF-7/Adr human breast cancer cells. METHODS: The expression of ER in MCF-7 and MCF-7/Adr cells was determined using Western blot analysis. ER expression plasmid was constructed and introduced into MCF-7/Adr cells using LipofectAMINE. After G418 screening, the positive clone (MTER/Adr) was obtained. The integration and expression of ER gene were analyzed by polymerase chain reaction (PCR) and Western blot. The cell cycle distribution was investigated by flow cytometry. The effects of droloxifene and Adriamycin on the growth of cells were investigated by MTT assay. RESULTS: Western blot analysis showed that ER was positive in MCF-7 cells, but was negative in MCF-7/Adr cells. The ER expression plasmid was constructed and introduced into MCF-7/Adr cells. The integration and expression of ER gene were successful in positive clone -MTER/Adr cells. Droloxifene inhibited the growth of MCF-7 at the concentration of 10-20 micromol/L and the MCF-7/Adr only at concentration of 20 micromol/L. Droloxifene inhibited the growth of MTER/Adr at the concentration of 15 micromol/L, and the percentage of MTER/Adr cells increased in G0/G1 phase. The sensitivity of MTER/Adr cells to Adriamycin increased. CONCLUSION: The insensitivity of MCF-7/Adr human breast cancer cells to droloxifene was associated with the loss of ER. MTER/Adr cells partially restore the sensitivity to droloxifene and Adriamycin.

[The binding sites of estrogen receptor for miyabenol C and kobophenol A].

To examine the binding sites of miyabenol C (Miy C) and kobophenol A ( Kob A) with estrogen receptor (ER), computer modeling was applied to determine 3D structure of Miy C and Kob A. Molecular docking of the components to ER was carried out to find the binding sites between them. PCR mutagenesis was used to change the structure of ER cDNA. After the mutated sites were confirmed by DNA sequencing, report gene assay was used to study the effects of Miy C and Kob A on the trans-activating ability of ER. Results indicated that the effect of Miy C on the trans-activating ability of mutant 1 of ER [M1ER (ER M(517)AG(521)D)] was decreased, and Kob A had no stimulating effects on the trans-activating ability of M1ER. Miy C and Kob A had no stimulating effects on the trans-activating ability of mutant 2 of ER [M2ER (ER E(353)GR(394)G)]. Therefore, the ER sites for Miy C and Kob A may be located at Glu(353), Arg(394), Met(517) and Gly(521).