The tumour hypoxia marker pimonidazole reflects a transcriptional programme associated with aggressive prostate cancer.

BACKGROUND: The hypoxia marker pimonidazole is a candidate biomarker of cancer aggressiveness. We investigated the transcriptional programme associated with pimonidazole staining in prostate cancer. METHODS: Index tumour biopsies were taken by image guidance from an investigation cohort of 52 patients, where 43 patients received pimonidazole before prostatectomy. Biopsy location within the index tumour was verified for 46 (88%) patients, who were included for gene expression profiling and immunohistochemistry. Two independent cohorts of 59 and 281 patients were used for validation. RESULTS: Expression of genes in proliferation, DNA repair and hypoxia response was a major part of the transcriptional programme associated with pimonidazole staining. A signature of 32 essential genes was constructed and showed positive correlation to Ki67 staining, confirming the increased proliferation in hypoxic tumours as suggested from the gene data. Positive correlations were also found to tumour stage and lymph node status, but not to blood prostate-specific antigen level, consistent with the findings for pimonidazole staining. The association with aggressiveness was confirmed in validation cohorts, where the signature correlated with Gleason score and had independent prognostic impact, respectively. CONCLUSIONS: Pimonidazole staining reflects an aggressive hypoxic phenotype of prostate cancer characterised by upregulation of proliferation, DNA repair and hypoxia response genes.

Heterogeneity of intraepithelial lymphocytes in refractory sprue: potential implications of CD30 expression.

BACKGROUND: Refractory sprue is defined as primary or secondary failure to respond to a gluten free diet in patients with coeliac disease-like enteropathy and may signify cryptic or overt enteropathy associated T cell lymphoma. AIMS: To study in detail jejunal morphology and immunophenotypes in patients with refractory sprue in the search for features that might be useful to predict prognosis. PATIENTS: Seven patients are described, representing all such cases identified in our hospital over a 13 year period. METHODS: Biopsy and/or surgical resection specimens were examined by morphology, immunohistochemistry, including enzymatic and immunofluorescent detection, and molecular biology. RESULTS: All patients had phenotypically abnormal intraepithelial lymphocytes (IELs) that lacked CD8, T cell receptor alpha beta (or gamma delta), and/or expressed CD30 in addition to variable expression of the natural killer cell receptor CD94. A monoclonal T cell population was present in six cases, data from the seventh being inconclusive. Three patients had overt lymphoma with CD30+ tumour tissue intervening between intact mucosa that contained neoplastic IELs. Intriguingly, CD30+ IELs were observed both a long way away from, and in direct continuity with, the tumours in these patients. Such CD30+ cells were hardly detected in patients without tumours, two of which are in good health several years after the initial diagnosis. CONCLUSIONS: Our data suggest that abnormal IELs in patients with refractory sprue are phenotypically heterogeneous. CD30 expression by these cells may indicate a worse prognosis, including the occurrence of overt lymphoma.

A review of caveats in statistical nuclear image analysis.

A large body of the published literature in nuclear image analysis do not evaluate their findings on an independent data set. Hence, if several features are evaluated on a limited data set over-optimistic results are easily achieved. In order to find features that separate different outcome classes of interest, statistical evaluation of the nuclear features must be performed. Furthermore, to classify an unknown sample using image analysis, a classification rule must be designed and evaluated. Unfortunately, statistical evaluation methods used in the literature of nuclear image analysis are often inappropriate. The present article discusses some of the difficulties in statistical evaluation of nuclear image analysis, and a study of cervical cancer is presented in order to illustrate the problems. In conclusion, some of the most severe errors in nuclear image analysis occur in analysis of a large feature set, including few patients, without confirming the results on an independent data set. To select features, Bonferroni correction for multiple test is recommended, together with a standard feature set selection method. Furthermore, we consider that the minimum requirement of performing statistical evaluation in nuclear image analysis is confirmation of the results on an independent data set. We suggest that a consensus of how to perform evaluation of diagnostic and prognostic features is necessary, in order to develop reliable tools for clinical use, based on nuclear image analysis.

Comparison of the immunocytochemical assay (ER-ICA) and the biochemical assay for estrogen receptor in human breast cancer cell lines.

Estrogen receptor content of 8 cell lines from non-malignant human breast tissues was determined by an immunocytochemical assay using the Abbott ER-ICA monoclonal kit. The results were in accordance with those obtained by the conventional radiochemical (DCC) assay. Primary cultures of breast tissues are suggested as an important field for in situ application of the ER-ICA.