Applications of array technology: melanoma research and diagnosis.

A complex set of genetic alterations occurs within a cell in order to permit neoplastic transformation. Human cancers undergo a continuous development from benign to malignant states, as most thoroughly documented in the mole-to-melanoma transition. Several specific genetic and transcriptional events correlate with the prolonged multistep sequence from early to late clinical stages of the disease. High-throughput microarrays are being used in expression profiling analyses with the aim of discovering genes and their pathways, functional characterization of genes and tumor subclassification. There are, however, many potential pitfalls in the use of microarrays that result in false leads and erroneous conclusions. This review summarizes the current status of the application of microarray technology in melanoma research. It also attempts to outline some of the steps needed to develop the key features to be observed in developing diagnostic and prognostic classification systems based upon gene expression profiling.

Critical size of residual adrenal tissue and recovery from impaired early postoperative adrenocortical function after subtotal bilateral adrenalectomy.

BACKGROUND: Subtotal bilateral adrenalectomy may preserve adrenocortical function. Little is known about the early postoperative function of the adrenal remnant. METHOD: In 10 patients with bilateral adrenal tumors (pheochromocytomas, adrenocortical nodular hyperplasia, and adrenal metastases), plasma adrenocorticotropic hormone (ACTH), serum cortisol, and maximal cortisol liberation were examined with an ACTH test after subtotal bilateral adrenalectomy, which left 15% to 30% of adrenal tissue in situ. RESULTS: In the early postoperative period, all patients had normal basal serum cortisol levels (mean, 415+/-208 nmol/L; normal morning range, 138-690 nmol/L) but pathologically increased plasma ACTH levels (mean, 55+/-42 pmol/mL; normal, <10.1 pmol/L). In 6 patients, a pathologic ACTH test result was observed. During follow-up (mean, 11.3+/-7.6 months), all patients were found to have a normal ACTH test result. None of the patients required steroid supplementation. However, in patients with both familial pheochromocytoma and impaired adrenocortical function during the early postoperative period, the maximal increase of serum cortisol after ACTH stimulation was significantly reduced (mean, 301+/-86.8 nmol/L) compared with control subjects (mean, 490+/-132.6 nmol/L; P=.019). CONCLUSION: After subtotal bilateral adrenalectomy left 15% to 30% of adrenal tissue in situ, functional recovery could be observed in all patients. However, subclinical impairment of the adrenocortical function with questionable clinical significance has to be considered in some of the patients. Especially during the early postoperative period, careful observation of the patients without exogenous steroid administration is required.

Spectrum of bacterial isolates in HIV-positive patients with skin and soft tissue infections: emergence of methicillin-resistant Staphylococci.

We assessed the spectrum of bacteria in skin and soft tissue infections (SSTI) between HIV-negative and HIV-positive patients, and compared the emergence of resistance at a university dermatology department during 1995-2000. Of 10,456 isolates, Staphylococcus aureus, coagulase-negative Staphylococci, Streptococcus spp., Escherichia coli and Pseudomonas aeruginosa were the most significantly increased over the years. The knowledge of the evolving spectrum of bacteria anf their resistance pattern is imperative to treat SSTI adequately.

Functional results after endoscopic subtotal cortical-sparing adrenalectomy.

PURPOSE: We examined the required amount of residual adrenal tissue and whether an intact adrenal vein are necessary to achieve sufficient function after endoscopic subtotal adrenalectomy. METHOD: Endoscopic subtotal adrenalectomy was performed in 14 patients. Two patients underwent unilateral subtotal and contralateral total adrenalectomy and another two patients underwent unilateral subtotal adrenalectomy after contralateral total adrenalectomy several years earlier. We analyzed the postoperative serum levels of cortisol and adrenocorticotropic hormone (ACTH). Patients with bilateral tumors underwent an ACTH test. RESULTS: We had to cut the main adrenal vein in ten patients, and less than one third of the adrenal gland was left in situ in four patients. Subtotal adrenalectomy was performed unilaterally in two patients with bilateral tumors. One third of the adrenal gland was preserved in these patients, and also in the two patients with unilateral subtotal adrenalectomy after previous contralateral total adrenalectomy. The postoperative ACTH test confirmed satisfactory adrenocortical function. During the follow-up period of about 24 months no recurrent tumors have been found. CONCLUSION: Subtotal cortical-sparing adrenalectomy can be successfully performed laparoscopically. The venous drainage of the main adrenal vein does not seem to be crucial for sufficient adrenocortical function. We estimate that leaving about one third of the entire adrenal gland as remnant adrenal tissue will result in sufficient function.

Reaction of keratinocytes to exogenous DNA.

Keratinocytes have the ability to take up oligonucleotides (ODN) and plasmid DNA probably by receptor-mediated endocytosis or macropinocytosis. Despite the use of DNA for antisense and gene therapy, little is known about the regulation of genes following exposure to nucleic acids. To systematically identify gene regulation in keratinocytes upon exposure to ODN, we screened human cytokine DNA arrays containing 383 different genes and found interleukin-1 alpha (IL-1 alpha), IL-1 beta, integrin beta1, alpha-tubulin and follistatin greatly induced, while most genes were unaffected. The time course and concentration dependence for IL-1 alpha and follistatin was confirmed by the standard Northern blot technique and found to be induced by picomolar or femtomolar concentrations of ODN. ODN of different length and sequence induced comparable amounts of IL-1 alpha and follistatin. Their induction was independent of the negative charge and of several proinflammatory compounds and proteins such as lipopolysaccharides, IL-1 beta or IFN-gamma, but was partly inhibited by activin A. In summary, our study revealed several genes of the acute phase protein family that were induced in a non-sequence-specific manner following the exposure of normal human keratinocytes to ODN. Therefore, it is tempting to speculate that, upon internalization, ODN bind to an intracellular receptor (e.g. Toll-like receptor 9), which mediates signaling.

Induction of acute phase response genes in keratinocytes following exposure to oligodeoxynucleotides.

Keratinocytes have the ability to take up oligodeoxynucleotides (ODN) and plasmid DNA probably by receptor-mediated endocytosis. Despite the use of DNA for antisense and gene therapy little is known about the regulation of genes following exposure to nucleic acids. To systematically identify gene regulation in keratinocytes upon exposure to ODN we screened human cytokine DNA arrays containing 383 different genes and found interleukin (IL) 1alpha, IL-1beta, integrin-beta(1), alpha-tubulin, and follistatin highly induced, while most genes were unaffected. The time course and concentration dependence for IL-1alpha and follistatin expression were analyzed by standard northern blot technique. ODN of different length and sequence induced comparable amounts of IL-1alpha and follistatin. Their induction was independent of negative charge and of several proinflammatory compounds such as lipopolysaccharides, IL-1beta, and interferon-gamma but was partly inhibited by activin A. In summary, our study revealed several genes of the acute phase protein family that are induced in a non-sequence-specific manner following the exposure of normal human keratinocytes to ODN. Therefore it is tempting to speculate that upon internalization ODN bind to an intracellular receptor (e.g., Toll-like receptor 9) which mediates signaling.