Microsatellite instability (MSI), characterized by contraction or expansion in microsatellite length or short tandem repeats compared with germline lengths, is found in 85% to 90% of colon cancer arising in hereditary nonpolyposis colorectal cancer families. These cancers commonly have characteristic histologic appearances, including medullary features with intense lymphoid infiltrates. In pancreatic cancer, a rare medullary histologic subtype more often demonstrates MSI than the more common adenocarcinoma subtype. We hypothesized that the medullary histologic pattern might correlate with MSI in additional tumor types and analyzed 8 cases of typical and atypical medullary carcinoma of the breast. Tumor and normal DNA was extracted from paraffinized tissue blocks of tumor and histologically uninvolved axillary lymph nodes, respectively. We analyzed the tumors for instability in 5 primary (BAT25, BAT26, D17S250, D5S346, D2S123) and 3 alternative (BAT40, D18S55, D18S58) microsatellites recommended at the National Cancer Institute--sponsored conference for diagnosis of MSI in colorectal cancer. All 8 tumors were microsatellite stable at the 8 loci, suggesting that MSI is not commonly associated with medullary or atypical medullary breast carcinoma, in contrast with the reported association with medullary tumors of the colon and pancreas.

Expression of the Y-box protein YB-1 is increased in proliferating normal and cancer cells, but its role in cell proliferation and cell cycle progression is unclear. We have identified a cell cycle-dependent relocalization of YB-1 from the cytoplasm to the nucleus at the G 1 /S phase transition and demonstrate that both the charged zipper and the cold shock domain are involved in regulating this process. Using cell lines that constitutively overexpress YB-1, we show that nuclear accumulation of YB-1 is associated with increased cyclin A and cyclin B1 mRNA and protein expression. We provide evidence that deregulated YB-1 expression is linked to adhesion-independent cell proliferation through the induction of cyclin A. Thus, we have identified YB-1 as a cell cycle stage-specific transcription factor important for cell proliferation.

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YB-1 protein levels are elevated in most human breast cancers, and high YB-1 levels have been correlated with drug resistance and poor clinical outcome. YB-1 is a stress-responsive, cell cycle-regulated transcription factor with additional functions in RNA metabolism and translation. In this study, we show in a novel transgenic mouse model that human hemagglutinintagged YB-1 provokes remarkably diverse breast carcinomas through the induction of genetic instability that emerges from mitotic failure and centrosome amplification. The increase of centrosome numbers proceeds during breast cancer development and explanted tumor cell cultures show the phenotype of ongoing numerical chromosomal instability. These data illustrate a mechanism that might contribute to human breast cancer development. (Cancer Res 2005; 65(10): 4078-87)

The St. Gallen 5-tyre surrogate classification for breast cancer subtypes accurately predicts breast cancer presenting features (with emphasis on prediction of nodal involvement), recurrence patterns and disease free survival.

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Hepatic Candida infection (HCI; known as chronic disseminated candidosis or CDC) is a distinct form of disseminated Candida infection with predominant involvement of the liver. Diagnosis of HCI is usually made on clinical suspicion together with multiple lesions in liver on ultrasound (US), CT and/or MRI scan. Fungal elements may not always be visible in liver tissue and mycological culture is frequently negative, making the evidence for proven fungal disease difficult. We studied a novel commercially available low-cost and density-array (LCD) chip technique for a molecular diagnosis of HCI. This is a two-step procedure with PCR amplification after DNA extraction followed by hybridization on a small chip provided by the manufacturer (Fungi 2.1, Chipron GmbH). The analysis of DNA from 45 fungal control strains showed an excellent specificity and sensitivity. The DNA from 11 liver biopsies of patients with haematological malignancies suffering from CDC was analysed on the LCD chip and overall 11 fungal pathogens could be detected in eight liver biopsies, supporting the clinical diagnosis of HCI/CDC. Analysis of liver biopsies from controls was negative for fungal DNA in all samples studied. In conclusion, the novel LCD chip technique examined in our study was able to detect fungal pathogens in liver biopsies from patients with haematological malignancies and suspected HCI/CDC but was negative in control biopsies.

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