Clinical performance of two multi-marker blood tests for predicting malignancy in women with an adnexal mass.

BACKGROUND: Reliable methods that allow appropriate triage of women with an adnexal mass to a gynecologic oncologist are needed. We evaluated the clinical performance of OVA1 and ROMA for the prediction of malignancy in women with an adnexal mass. METHODS: One hundred forty-six prospectively collected serum samples were collected from women with an adnexal mass, 31 of whom had surgically confirmed malignancies. OVA1 and ROMA tests were performed on all samples. Receiver operating characteristic curve analysis was used to determine interpretive cutoffs for ROMA. Performance characteristics of both tests were determined and compared. RESULTS: The sensitivity of OVA1 and ROMA was 97% and 87%, respectively (p=0.25). ROMA was more specific than OVA1 (83% vs. 55%, respectively; p<0.0001). The negative predictive values of both tests were similar (98.4% and 96.0%, respectively). ROMA performed on all patients identified as high risk by OVA1 (a sequential strategy) produced a positive predictive value of 69%. CONCLUSIONS: OVA1 and ROMA have similar performance characteristics, with OVA1 having non-significant greater diagnostic sensitivity and ROMA having greater diagnostic specificity. The use of these tests to appropriately triage women with an adnexal mass should be gauged within the context of their respective limitations. A sequential testing strategy may improve overall performance.

Preferences for blood-based colon cancer screening differ by race/ethnicity.

OBJECTIVES: To examine attitudes of a diverse community-based sample toward SEPT9, a simple, cost-effective colorectal cancer (CRC) blood test. METHODS: One-hundred participants eligible for CRC screening (Mage =58.3; 44% unscreened; 38% white, 31% Hispanic, 31% black) completed cross-sectional surveys of their screening preferences following group discussions of colonoscopy, sigmoidoscopy, FOBT, and SEPT9. RESULTS: Overall, 91% ranked SEPT9 first or second. Controlling for sociodemographic factors, unscreened Whites strongly preferred SEPT9, listing multiple advantages, whereas unscreened Blacks preferred colonoscopy. Only 19% of the sample listed negative aspects. CONCLUSION: Blood-based screening for CRC was widely favored. Future research on medical decision-making should examine the basis for racial/ethnic differences in biomarker screening preferences.

Blood-based testing for colorectal cancer screening.

Colorectal cancer (CRC) is the third most common non-skin cancer diagnosed in men and women in the USA and worldwide. While it has been clearly established that screening for CRC, using a variety of methods, is cost effective and has a significant impact on overall survival, screening rates have proven to be sub-optimal. It has been long conjectured that a simple blood-based test, with a specimen drawn at a routine doctor's office visit, would encourage those individuals who have refused or ignored screening recommendations to undergo screening. This article reviews the currently available blood-based screening tests for CRC, including the ColonSentry™ messenger RNA (mRNA) expression panel and the SEPT9 methylated DNA test, and explores newer biomarkers that are near clinical implementation. Also discussed are additional applications for blood-based CRC testing, such as assessing prognosis, disease surveillance, and expansion of screening tests to high-risk populations, such as the estimated 1.4 million individuals in the USA with inflammatory bowel disease.

DNA methylation biomarkers and their utility for solid cancer diagnostics.

Cellular DNA undergoes profound changes in methylation during cancer development, with hypermethylation occurring in specific gene promoters, amidst a backdrop of generalized hypomethylation. DNA methylation in cancer often causes the silencing of tumor suppressors and other genes important for cellular growth, regulation and differentiation. Over the past two decades, there have been thousands of publications describing the methylation status of hundreds of genes in cancer, with numerous associations with clinical states, disease outcomes and therapeutic responses being reported. New methods for DNA methylation fingerprinting have emerged, allowing for the exponential growth of "epigenomic" information. Despite this wealth of data, only a handful of methylated genes are utilized as cancer biomarkers in the clinical laboratory. A literature review centered on DNA methylation in six solid cancers was performed, including colorectal, pancreatic, prostate, bladder, breast and ovarian. Commonly methylated genes in the six cancer types were identified and catalogued, and could serve in the future as tissue-based biomarkers or as part of cancer-specific panels. Perhaps more importantly, this endeavor has also focused on methylated genes that appear to be unique to particular cancers. These genes may be more versatile for clinical use, with blood or urine-based cancer screening becoming a reality.

The atypical histone macroH2A1.2 interacts with HER-2 protein in cancer cells.

Because HER-2 has been demonstrated in the nuclei of cancer cells, we hypothesized that it might interact with transcription factors that activate ERBB2 transcription. Macrohistone 2A1 (H2AFY; mH2A1) was found to interact with HER-2 in cancer cells that overexpress HER-2. Of the two human mH2A1 isoforms, mH2A1.2, but not mH2A1.1, interacted with HER-2 in human cancer cell lines. Overexpression of mH2A1.2, but not mH2A1.1, in cancer cells significantly increased HER-2 expression and tumorigenicity. Inhibition of HER-2 kinase activity diminished mH2A1 expression and mH2A1.2-induced ERBB2 transcription in cancer cells. Chromatin immunoprecipitation of mH2A1.2 in cancer cells stably transfected with mH2A1.2 showed enrichment of mH2A1.2 at the HER-2 promoter, suggesting a role for mH2A1.2 in driving HER-2 overexpression. The evolutionarily conserved macro domain of mH2A1.2 was sufficient for the interaction between HER-2 and mH2A1.2 and for mH2A1.2-induced ERBB2 transcription. Within the macro domain of mH2A1.2, a trinucleotide insertion (-EIS-) sequence not found in mH2A1.1 was essential for the interaction between HER-2 and mH2A1.2 as well as mH2A1.2-induced HER-2 expression and cell proliferation.

Septin 9 methylated DNA is a sensitive and specific blood test for colorectal cancer.

BACKGROUND: About half of Americans 50 to 75 years old do not follow recommended colorectal cancer (CRC) screening guidelines, leaving 40 million individuals unscreened. A simple blood test would increase screening compliance, promoting early detection and better patient outcomes. The objective of this study is to demonstrate the performance of an improved sensitivity blood-based Septin 9 (SEPT9) methylated DNA test for colorectal cancer. Study variables include clinical stage, tumor location and histologic grade. METHODS: Plasma samples were collected from 50 untreated CRC patients at 3 institutions; 94 control samples were collected at 4 US institutions; samples were collected from 300 colonoscopy patients at 1 US clinic prior to endoscopy. SEPT9 methylated DNA concentration was tested in analytical specimens, plasma of known CRC cases, healthy control subjects, and plasma collected from colonoscopy patients. RESULTS: The improved SEPT9 methylated DNA test was more sensitive than previously described methods; the test had an overall sensitivity for CRC of 90% (95% CI, 77.4% to 96.3%) and specificity of 88% (95% CI, 79.6% to 93.7%), detecting CRC in patients of all stages. For early stage cancer (I and II) the test was 87% (95% CI, 71.1% to 95.1%) sensitive. The test identified CRC from all regions, including proximal colon (for example, the cecum) and had a 12% false-positive rate. In a small prospective study, the SEPT9 test detected 12% of adenomas with a false-positive rate of 3%. CONCLUSIONS: A sensitive blood-based CRC screening test using the SEPT9 biomarker specifically detects a majority of CRCs of all stages and colorectal locations. The test could be offered to individuals of average risk for CRC who are unwilling or unable to undergo colonscopy.

Six1 expands the mouse mammary epithelial stem/progenitor cell pool and induces mammary tumors that undergo epithelial-mesenchymal transition.

Six1 is a developmentally regulated homeoprotein with limited expression in most normal adult tissues and frequent misexpression in a variety of malignancies. Here we demonstrate, using a bitransgenic mouse model, that misexpression of human Six1 in adult mouse mammary gland epithelium induces tumors of multiple histological subtypes in a dose-dependent manner. The neoplastic lesions induced by Six1 had an in situ origin, showed diverse differentiation, and exhibited progression to aggressive malignant neoplasms, as is often observed in human carcinoma of the breast. Strikingly, the vast majority of Six1-induced tumors underwent an epithelial-mesenchymal transition (EMT) and expressed multiple targets of activated Wnt signaling, including cyclin D1. Interestingly, Six1 and cyclin D1 coexpression was found to frequently occur in human breast cancers and was strongly predictive of poor prognosis. We further show that Six1 promoted a stem/progenitor cell phenotype in the mouse mammary gland and in Six1-driven mammary tumors. Our data thus provide genetic evidence for a potent oncogenic role for Six1 in mammary epithelial neoplasia, including promotion of EMT and stem cell-like features.

The Six1 homeoprotein induces human mammary carcinoma cells to undergo epithelial-mesenchymal transition and metastasis in mice through increasing TGF-beta signaling.

Inappropriate activation of developmental pathways is a well-recognized tumor-promoting mechanism. Here we show that overexpression of the homeoprotein Six1, normally a developmentally restricted transcriptional regulator, increases TGF-beta signaling in human breast cancer cells and induces an epithelial-mesenchymal transition (EMT) that is in part dependent on its ability to increase TGF-beta signaling. TGF-beta signaling and EMT have been implicated in metastatic dissemination of carcinoma. Accordingly, we used spontaneous and experimental metastasis mouse models to demonstrate that Six1 overexpression promotes breast cancer metastasis. In addition, we show that, like its induction of EMT, Six1-induced experimental metastasis is dependent on its ability to activate TGF-beta signaling. Importantly, in human breast cancers Six1 correlated with nuclear Smad3 and thus increased TGF-beta signaling. Further, breast cancer patients whose tumors overexpressed Six1 had a shortened time to relapse and metastasis and an overall decrease in survival. Finally, we show that the effects of Six1 on tumor progression likely extend beyond breast cancer, since its overexpression correlated with adverse outcomes in numerous other cancers including brain, cervical, prostate, colon, kidney, and liver. Our findings indicate that Six1, acting through TGF-beta signaling and EMT, is a powerful and global promoter of cancer metastasis.