BackgroundColorectal cancer (CRC) is the second leading cause of cancer deaths despite the fact that detection of this cancer in early stages results in over 90% survival rate. Currently less than 45% of at-risk individuals in the US are screened regularly, exposing a need for better screening tests. We performed two case-control studies to validate a blood-based test that identifies methylated DNA in plasma from all stages of CRC.Methodology/Principal FindingsUsing a PCR assay for analysis of Septin 9 (SEPT9) hypermethylation in DNA extracted from plasma, clinical performance was optimized on 354 samples (252 CRC, 102 controls) and validated in a blinded, independent study of 309 samples (126 CRC, 183 controls). 168 polyps and 411 additional disease controls were also evaluated. Based on the training study SEPT9-based classification detected 120/252 CRCs (48%) and 7/102 controls (7%). In the test study 73/126 CRCs (58%) and 18/183 control samples (10%) were positive for SEPT9 validating the training set results. Inclusion of an additional measurement replicate increased the sensitivity of the assay in the testing set to 72% (90/125 CRCs detected) while maintaining 90% specificity (19/183 for controls). Positive rates for plasmas from the other cancers (11/96) and non-cancerous conditions (41/315) were low. The rate of polyp detection (>1 cm) was ∼20%.Conclusions/SignificanceAnalysis of SEPT9 DNA methylation in plasma represents a straightforward, minimally invasive method to detect all stages of CRC with potential to satisfy unmet needs for increased compliance in the screening population. Further clinical testing is warranted.

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Recently, expression profiling of breast carcinomas has revealed gene signatures that predict clinical outcome, and discerned prognostically relevant breast cancer subtypes. Measurement of the degree of genomic instability provides a very similar stratification of prognostic groups. We therefore hypothesized that these features are linked. We used gene expression profiling of 48 breast cancer specimens that profoundly differed in their degree of genomic instability and identified a set of 12 genes that defines the 2 groups. The biological and prognostic significance of this gene set was established through survival prediction in published datasets from patients with breast cancer. Of note, the gene expression signatures that define specific prognostic subtypes in other breast cancer datasets, such as luminal A and B, basal, normal‐like, and ERBB2+, and prognostic signatures including MammaPrint® and Oncotype DX, predicted genomic instability in our samples. This remarkable congruence suggests a biological interdependence of poor‐prognosis gene signatures, breast cancer subtypes, genomic instability, and clinical outcome. © 2008 Wiley‐Liss, Inc.

Numerous investigations have shown that in primary breast adenocarcinomas DNA aneuploidy in contrast to DNA diploidy indicates high malignancy potential. On the basis of the study of 104 breast carcinomas, we describe a subtype of aneuploidy, which demonstrates a low degree of malignancy. In image cytometric DNA histograms, this subtype possessed a low percentage (< or = 8.8%) of nonmodal DNA values as measured by the stemline scatter index (SSI), which is defined as sum of the percentage of cells in the S-phase region, the G(2) exceeding rate and the coefficient of variation of the tumor stemline. The cut point of SSI = 8.8% (P = 0.03) enabled us to also subdivide diploid and tetraploid tumors into clinically low and high malignant variants. One possible reason for aneuploidy is impaired distribution of chromosomes at mitosis caused by numerical or structural centrosome aberrations. Cyclins A and E seem to be involved in centrosome duplication. Real-time quantitative PCR measurements of cyclin A and E transcript levels and immunohistochemical determination of cyclin A protein expression showed statistically significantly increased values in the tumors with a high SSI (>8.8%), compared with those with a low SSI. A pilot study demonstrated centrosomal aberrations in an average of 9.6% of the measured cells in four aneuploid carcinomas with high SSI values and in an average of 2.5% of the cells in three aneuploid and three diploid tumors with low SSI. Our data indicate that the SSI, most likely reflecting the degree of genomic instability, allows additional classifying of the known aneuploid, diploid, and tetraploid categories of primary breast adenocarcinomas into low and high malignant subtypes.

To identify sequential alterations of the genome, transcriptome, and proteome during colorectal cancer progression, we have analyzed tissue samples from 36 patients, including the complete mucosa-adenoma-carcinoma sequence from 8 patients. Comparative genomic hybridization (CGH) revealed patterns of stage specific, recurrent genomic imbalances. Gene expression analysis on 9K cDNA arrays identified 58 genes differentially expressed between normal mucosa and adenoma, 116 genes between adenoma and carcinoma, and 158 genes between primary carcinoma and liver metastasis (P < 0.001). Parallel analysis of our samples by CGH and expression profiling revealed a direct correlation of chromosomal copy number changes with chromosome-specific average gene expression levels. Protein expression was analyzed by two-dimensional gel electrophoresis and subsequent mass spectrometry. Although there was no direct match of differentially expressed proteins and genes, the majority of them belonged to identical pathways or networks. In conclusion, increasing genomic instability and a recurrent pattern of chromosomal imbalances as well as specific gene and protein expression changes correlate with distinct stages of colorectal cancer progression. Chromosomal aneuploidies directly affect average resident gene expression levels, thereby contributing to a massive deregulation of the cellular transcriptome. The identification of novel genes and proteins might deliver molecular targets for diagnostic and therapeutic interventions.

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While the above named markers show high screening potential for pancreatic cancer, standardized validation studies using multiplex assays are required to pave the way for clinical routine application.

Fournier's gangrene remains a major challenge with a high mortality. Our results suggest that women are more commonly affected than has generally been assumed. Contrary to published reports, we found that anorectal sources appear to account for more cases of Fournier's gangrene than urological sources.