Multiple microRNAs as biomarkers for early breast cancer diagnosis.

MicroRNA (miRNA or miR) is stably present in plasma. It has been reported that miRNA could be used for detecting cancer. Circulating miRNAs are being increasingly recognized as powerful biomarkers in a number of different pathologies, including in breast cancer. The aim of the current study was to establish and validate miRNA sets that are useful for the early diagnosis of breast cancer. Specifically, the current study intended to determine whether miRNA biomarkers were tumor-specific and to statistically verify whether circulating miRNA analysis could be used for breast cancer diagnosis. In the present study, a total of nine candidate miRNA biomarkers were selected by examining reference miRNAs associated with the generation and progression of breast cancer to identify novel miRNAs that could be used to detect early breast cancer. A total of 226 plasma samples from patients with breast cancer were used. In addition, 146 plasma healthy samples were used as non-cancer controls. These samples were divided into training and validation cohorts. The training cohort was used to identify a combination of miRNA that could detect breast cancer. The validation cohort was used to validate this combination of miRNA. Total RNAs were isolated from collected samples. A total of 9 miRNAs were quantified using reverse-transcription quantitative PCR. A total of nine candidate miRNA expression levels were compared between patients with breast cancer and healthy controls. It was indicated that combinations of two or more of the nine miRNAs could detect breast cancer with higher accuracy than the use of a single biomarker. As a representative example, combinations of four miRNAs (miR-1246+miR-206+miR-24+miR-373) of the nine miRNAs had a sensitivity of 98%, a specificity of 96% and an accuracy of 97% for breast cancer detection in the validation cohort. The results of the present study suggest that multiple miRNAs could be used as potential biomarkers for early diagnosis of breast cancer. These biomarkers are expected to overcome limitations of mammography when used as an auxiliary diagnosis of mammography.

Evaluation of the Effectiveness of Pandemic Influenza A(H1N1) 2009 Vaccine Based on an Outbreak Investigation During the 2010-2011 Season in Korean Military Camps.

OBJECTIVES: In December 2010, there was an outbreak of acute febrile respiratory disease in many Korean military camps that were not geographically related. A laboratory analysis confirmed a number of these cases to be infected by the pandemic influenza A(H1N1) 2009 (H1N1pdm09) virus. Because mass vaccination against H1N1pdm09 was implemented at the infected military camps eleven months ago, the outbreak areas in which both vaccinated and nonvaccinated individuals were well mixed, gave us an opportunity to evaluate the effectiveness of H1N1pdm09 vaccine through a retrospective cohort study design. METHODS: A self-administered questionnaire was distributed to the three military camps in which the outbreak occurred for case detection, determination of vaccination status, and characterization of other risk factors. The overall response rate was 86.8% (395/455). Case was defined as fever (≥38 °C) with cough or sore throat, influenza-like illness (ILI), and vaccination status verified by vaccination registry. Crude vaccine effectiveness (VE) was calculated as "1 - attack rate in vaccinated individuals/attack rate in nonvaccinated individuals", and adjusted VE was calculated as "1 - odds ratio" using logistic regression adjusted for potential confounding factor. A number of ILI definitions were used to test the robustness of the result. RESULTS: The attack rate of ILI was 12.8% in register-verified vaccinated individuals and 24.0% in nonvaccinated individuals. The crude VE was thus calculated to be 46.8% [95% confidence interval (CI): 14.5-66.9]. The adjusted VE rate was 46.8% (95% CI: -9.4 to 74.1). Various combinations of ILI symptoms also showed similar VE rates. CONCLUSION: We evaluated the effectiveness of H1N1pdm09 vaccine in the 2010-2011 season in an outbreak setting. Although the result was not sensitive to any analytical method used and ILI case definition, the magnitude of effectiveness was lower than estimated in the 2009-2010 season.

Collagen triple helix repeat containing-1 (CTHRC1) expression in invasive ductal carcinoma of the breast: the impact on prognosis and correlation to clinicopathologic features.

CTHRC1 has been known as a regulator of collagen expression and cell migration. The aim of this research was to clarify the clinicopathologic significance of CTHRC1 expression in human breast cancer. 22 cases of breast cancer tissues, randomly selected from clinically diagnosed patients, showed a significant increase of CTHRC1 mRNA expression compared to the normal tissue from the same patients using RT-PCR and real-time PCR. Additionally we investigated breast cancers from 189 patients by immunohistochemistry (IHC). A high level of CTHRC1 expression was observed in 111 (58.7 %) out of 189 breast cancer patients and the expression was significantly correlated with histologic grade (P = 0.026), nodal status (P < 0.001), and TNM pathologic stage (P = 0.002). High CTHRC1 expression was associated with a shorter recurrence free survival (P = 0.008). Taken together, the results showed that CTHRC1 over-expression was significantly associated with clinicopathological factors of poor prognosis in invasive ductal carcinoma. CTHRC1 could be used as a supplementary prognostic biomarker and a potential therapeutic target in breast cancer.

Overexpression and clinical significance of carcinoembryonic antigen-related cell adhesion molecule 6 in colorectal cancer.

BACKGROUND: Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) inhibits anoikis and affects the malignant phenotype of cancer cells. In this study, we analyzed CEACAM6 as a gene that is highly upregulated in colon cancer tissues, and examined the assertion that CEACAM6 might be a suitable candidate tumor marker for the diagnosis of colon cancer. METHODS: CEACAM6 gene expression in human colon tissues was performed by tissue microarray and analyzed using RT-PCR (each of normal and tumor tissue, n=40) and immunohistochemical and clinicopathological (colon cancer patients, n=143) analyses. RESULTS: CEACAM6 transcriptional and translational levels were significantly upregulated in human tumor tissues compared to non-tumor regions, and clinicopathological analysis revealed a significant correlation between CEACAM6 protein expression and Dukes' stage (p<0.001). High expression levels of CEACAM6 were significantly associated with lower overall survival (p<0.001) and shorter recurrence-free survival (p<0.001). We demonstrated that knockdown of CEACAM6 with CEACAM6-specific small interfering RNA in colorectal cancer cells attenuated invasivity (35%); conversely, the overexpression of CEACAM6 increased invasiveness. CONCLUSIONS: CEACAM6 is significantly upregulated in colon cancer tissues and is closely associated with poor prognosis, indicating that CEACAM6 might be used as a tumor biomarker and a potential therapeutic target for colon cancer.

Expression of endothelial cell-specific molecule-1 regulated by hypoxia inducible factor-1α in human colon carcinoma: impact of ESM-1 on prognosis and its correlation with clinicopathological features.

Based on a previous finding that endothelial cell-specific molecule-1 (ESM-1) is a potential serum marker for colorectal cancer (CRC), the aim of this study was to clarify the clinicopathological significance of ESM-1 expression in CRC, and to explore the correlation between ESM-1 and HIF-1α in the tumorigenesis of CRC related to hypoxic conditions. ESM-1 mRNA expression was examined in CRC and corresponding normal mucosal tissues by reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR. This experiment confirmed that ESM-1 levels were high in CRC. We screened the tissue samples of 143 CRC patients. By immunohistochemistry, we determined that the ESM-1 immunoreactivity was significantly correlated with the tumor size, depth of invasion, nodal status, distant metastasis and Dukes' stage, and was an independent prognostic factor for disease recurrence and worse survival outcome (P=0.001). The modulation of ESM-1 under hypoxia was investigated, and it was confirmed that ESM-1 expression was induced by HIF1-α and significantly attenuated by small interfering RNA (siRNA) targeting HIF-1α in CRC cells. These results showed that ESM-1 is significantly overexpressed, which is regulated by HIF-1α in CRC patients, and can be used as a potential biomarker and a therapeutic target for CRC.

NDRG2 correlated with favorable recurrence-free survival inhibits metastasis of mouse breast cancer cells via attenuation of active TGF-ß production.

N-myc downstream-regulated gene 2 (NDRG2) has been studied for its inhibitory effects against growth and metastasis of many tumor cell types. In this study, we showed NDRG2 expression was correlated with favorable recurrence-free survival of patients with breast cancer and inhibited metastasis of breast cancer cells (4T1). NDRG2 expression was examined in 189 breast carcinoma tissues and paired normal breast tissues using immunohistochemistry. Histological and clinicopathological data were correlated using Pearson's chi-square test of independence. NDRG2 expression in human breast cancer tissues was inversely associated with lymph node metastasis and pTNM stage. Furthermore, patients with breast cancer with a high level of NDRG2 expression showed favorable recurrence-free survival (P = 0.038). To study the effect of NDRG2 on metastasis in vivo, we established an NDRG2-overexpressing mouse breast cancer cell line (4T1-NDRG2) and measured the metastasis and survival of 4T1-NDRG2 tumor-bearing mice. To test whether transforming growth factor ß (TGF-ß)- mediated metastasis of 4T1 was inhibited by NDRG2 expression, TGF-Smad-binding element (SBE)-luciferase activity and/or measurement of active TGF-ß were performed in cell or tumor tissue level. 4T1-NDRG2 cells grew gradually and showed less metastatic activity in vivo and low invasiveness in vitro. 4T1-NDRG2 cells showed lower SBE-luciferase activity and lower level of active autocrine TGF-ß than 4T1-Mock did. Correctly, our data show that NDRG2 significantly suppress tumor metastasis by attenuating active autocrine TGF-ß production, and the attenuation might be typically associated with the favorable recurrence-free survival of patients clinically.

Up-regulation and clinical significance of serine protease kallikrein 6 in colon cancer.

BACKGROUND: Kallikrein-related peptidase 6 (KLK6) encodes a trypsin-like serine protease that is up-regulated in several cancers, although the putative functions of KLK6 in cancer have not been elucidated. In the current study, overexpression of KLK6 was identified in colon cancer, and the possibility that KLK6 may be a suitable candidate as a tumor marker was examined. METHODS: Messenger RNA (mRNA) transcript levels and protein up-regulation of KLK6 in colon cancer tissues was examined using reverse transcriptase-polymerase chain reaction, immunohistochemistry, and clinicopathologic analyses. Cell proliferation, invasiveness, and antiapoptotic activity were determined in colon cancer cells that were transfected with small-interfering RNA (siRNA) of KLK6. RESULTS: KLK6 mRNA was up-regulated significantly in tumor tissues compared with nontumor regions. KLK6 protein was strongly expressed in adenocarcinomas but was not expressed in normal mucosa or in premalignant dysplastic lesions. Sera from patients with colon cancer revealed an increase in KLK6 secretion (0.25 µg/mL; P = .031) compared with noncancer cells (0.19 µg/mL). Clinicopathologic and immunohistochemical studies of 143 patients with colon cancer revealed a significant correlation between KLK6 expression and Dukes disease stage (P = .005). High KLK6 expression was associated significantly with shorter overall (P = .001) and recurrence-free survival (P = .001). The rates of proliferation and invasiveness were decreased by 50% in cells that were transfected with KLK6 siRNA. The overexpression of KLK6 led to decreased activity of the E-cadherin promoter. CONCLUSIONS: KLK6 was up-regulated significantly in tissues and sera from patients with colon cancer and was associated closely with a poor prognosis, suggesting that KLK6 may be used as a potential biomarker and a therapeutic target for colon cancer.

[Mumps transmission control status and inapparent infection rate among middle and high school students during the 2007-2008 mumps outbreak in Daegu].

OBJECTIVES: This study was performed to investigate the mumps transmission control status and inapparent infection rate among middle and high school students in Daegu City during a mumps outbreak. METHODS: Nine schools (two middle schools and seven high schools), which reported a number of mumps cases between 2007 and 2008 were selected for investigation. During March-May 2008, a standard questionnaire was distributed to gather information about case identification, instructed isolation measure, isolation status of mumps cases and related factors, and outdoor activities of non-isolated mumps case. Inapparent infection rate was estimated by serum mumps IgM and IgG antibodies status and self-reported mumps symptoms in three of the nine schools. RESULTS: Among 2,560 respondents, more than half of students answered that they did not receive instructions in mumps transmission control measures during the outbreak. Among the 327 mumps cases identified by the questionnaire, 131 cases (40.1%) were considered as isolated and the isolation rates were significantly different among schools, grades, and gender. Of the non-isolated cases, 88.3% continued attending school. Inapparent mumps infection rates were between 56.3% and 70.2%. CONCLUSIONS: Mumps transmission control was inadequate to control the mumps outbreak. Although high inapparent infection rate would mitigate the transmission control effect of case isolation, this measure is fundamental for infection control. The reasons of this inadequate status need to be explored to develop an effective intervention strategy.