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Biobanks of fresh, unfixed human normal and malignant tissues represent a valuable source for gene expression analysis in translational cancer research and molecular pathology. However, the success of molecular and cellular analysis in both clinical and translational research is strongly dependent on the collection, handling, storage, and quality control of fresh human tissue samples. The aim of this study was to evaluate an innovative vacuum-based refrigerated system, as a logistically feasible technology to increase the collection of tissue specimens, preserving the integrity of cellular and molecular components. We tested randomly-selected tissues stored under vacuum at 4°C by using endpoints important for research and diagnosis, including tissue morphology, epitope stability, and RNA integrity. Gene expression was evaluated by qualitative and quantitative RT analysis of selected housekeeping and tissue-specific genes. Tissue morphology and overall protein stability were generally well preserved, being compromised only in gallbladder tissue. By contrast, phosphoprotein and RNA analysis demonstrated a time-dependent degree of degradation, with progressive loss of stability from 24 to 72 hours. However, this reduction in RNA quality did not represent a limitation for successful expression analysis of selected genes. Indeed, a comparative qualitative and quantitative RT-PCR analysis showed that RNA extracted from tissues stored under vacuum is suitable for gene expression profiling, but requires highly sensitive technologies, such as quantitative RT-PCR. These data suggest that the refrigerated vacuum-based system represents a suitable and feasible technology for routine transport of fresh specimens from surgery to biobanks, thus increasing the opportunity to collect biospecimens.

The recently-identified Wiskott-Aldrich syndrome protein gene (WASP) is responsible for the Wiskott-Aldrich X-linked immunodeficiency as well as for isolated X-linked thrombocytopenia (XLT). To characterize the regulatory sequences of the WASP gene, we have isolated, sequenced and functionally analyzed a 1.6-Kb DNA fragment upstream of the WASP coding sequence. Transfection experiments showed that this fragment is capable of directing efficient expression of the reporter chloramphenicol acetyltransferase (CAT) gene in all human hematopoietic cell lines tested. Progressive 5′ deletions showed that the minimal sequence required for hematopoietic-specific expression consists of 137 bp upstream of the transcription start site. This contains potential binding sites for several hematopoietic transcription factors and, in particular, two Ets-1 consensus that proved able to specifically bind to proteins present in nuclear extracts of Jurkat cells. Overexpression of Ets-1 in HeLa resulted in transactivation of the CAT reporter gene under the control of WASP regulatory sequences. Disruption of the Ets-binding sequences by side-directed mutagenesis abolished CAT expression in Jurkat cells, indicating that transcription factors of the Ets family play a key role in the control of WASP transcription.

We report on a 8-year-old patient affected by a selective T-cell defect associated with mental retardation and dysmorphic signs. At birth thymic aplasia and hypoparathyroidism were noted, suggesting a DiGeorge-like anomaly. The immunological evaluation during the 8 years follow-up revealed a progressive decrease of CD3+CD4+lymphocytes, which paralleled deficiencies of blood T cells. Chromosome analysis using GTL banding revealed an interstitial deletion of the short arm of chromosome 10. We next investigated whether the expression of IL-2R α chain and Nil-2-a genes, which are located on the short arm of chromosome 10, was affected by the deletion. Transcription of these two genes was normal, thus suggesting that the two regions were preserved.In situhybridization studies with the painting libraries #G3A7 and #G9 confirmed that the two regions were preserved and allowed us to define the breakpoint as 10p12-10p13. Due to the similarities between DiGeorge and 10p syndromes, we suggest that the 10p13-10p12 region contains a gene(s) potentially related to gene products of the 22q11 region, frequently altered in patients with DiGeorge.