Participation in the RACS sentinel node biopsy versus axillary clearance trial

Background: The Royal Australasian College of Surgeons (RACS) SNAC trial is a randomized controlled trial of sentinel node biopsy (SNB) versus axillary clearance (AC). It opened in May 2001 and is recruiting rapidly with good acceptance by consumers. Methods: A study of eligibility and treatment choices was conducted between November 2001 and September 2002 for women presenting with early breast cancer to 10 centres participating in the trial. Results: More than half of the 622 women (54%) were ineligible for trial entry because they had large (> 3 cm) or multicentric cancers. Participation was offered to 92% of eligible women and was taken up by 63%. The commonest reason for not participating was the desire to choose treatment rather than have it randomly allocated. Despite this there is a great acceptance of clinical trials because very few women (4% of those eligible) gave 'lack of interest in clinical trials' as the reason for non-participation. Few women who declined trial participation chose to have SNB alone (4.5% of those eligible). Conclusion: Sentinel node biopsy may become the standard of care for managing small breast cancers, but a significant number of patients will still require or choose axillary dissection. Results from large randomized trials are needed to determine the relative benefits and harms of SNB compared with AC. Surgeons must carefully discuss options for management with their patients.

Atypical prostatic glandular proliferations on needle biopsy - Diagnostic implications, use of immunohistochemistry, and clinical significance

In recent times, PSA screening and a substantial increase in prostate needle biopsies have not only resulted in detection of minute foci of cancer but have also very likely resulted in increased detection of atypical glandular proliferations. Not uncommonly, there are only a limited number of atypical glands in these biopsies, and these require careful evaluation to enable an accurate diagnosis. We describe diagnostic implications, use of immunohistochemistry, and clinical significance of these lesions. Foci of atypical glands, also labeled atypical small acinar proliferation of uncertain significance, have features suspicious for but not diagnostic of cancer. Atypical foci include a broad group of lesions of differing clinical significance. These include benign, small acinar proliferations mimicking prostate cancer and atypical glandular proliferations suspicious for carcinoma. Definite diagnosis requires accurate histopathologic assessment and judicious use of immunohistochemistry. Patients with atypical glands on prostate needle biopsy have a high risk for harboring cancer and therefore have an increased risk for having cancer detected in subsequent biopsies.

The matricellular protein SPARC is internalized in Sertoli, Leydig, and germ cells during testis differentiation

The gene encoding the matricellular protein secreted protein, acidic and rich in cysteine (SPARC) was identified in a screen for genes expressed sex-specifically during mouse gonad development, as being strongly upregulated in the male gonad from very early in testis development. We present here a detailed analysis of SPARC gene and protein expression during testis development, from 11.5 to 15.5 days post coitum (dpc). Section in situ hybridization analysis revealed that SPARC mRNA is expressed by the Sertoli cells in the testis cords and the fetal Leydig cells, found within the interstitial space between the testis cords. Immunodetection with anti-SPARC antibody showed that the protein was located inside the testis cords, within the cytoplasm of Sertoli and germ cells. In the interstitium, SPARC was present intracellularly within the Leydig cells. The internalization of SPARC in Sertoli, Leydig, and germ cells suggests that it plays an intracellular regulatory role in these cell types during fetal testis development.

Expression-based strategies for discovery of genes involved in testis and ovary development

In recent years, strategies for gene identification based on differential gene expression have become increasingly popular, due in part to the development of microarray technology. These strategies are particularly well suited to the identification of genes involved in sex determination and gonadal development, which unlike the development of other organ systems, proceeds along two very different alternative courses, depending on the sex of the embryo. We have used a high-throughput, array-based expression screen to identify several genes expressed sex-specifically in developing mouse gonads. One of these, vanin 1, appears to play a role in mediating migration of mesonephric cells into the male genital ridge. Progress in characterizing other genes arising from the screen is discussed.

The isolation and characterization of tescalcin, a novel gene differentially expressed in the mouse testis during the early stages of gonadal differentiation

Gonadal development is an ideal model to study organogenesis because a variety of developmental processes can be studied during the differentiation of the bipotential primordium into testis or ovary. To better understand this process, Representational Difference Analysis of cDNA was used to identify genes that are differentially expressed in mouse gonads at 13.5 days post-coitus. The analysis led to the identification of three testis specific genes and a sequence that was only expressed in the ovary. The male genes identified: renin, Col9a3, and a novel gene termed tescalcin had patterns of expression that suggested a role in testis determination. ^ Studies of the tescalcin gene revealed that it is organized into eight exons and seven introns. The gene was located at 64 cM in mouse chromosome 5, where it spans approximately 35 Kb. Three mRNA variants resulting from alternative splicing of intron 5 were identified in mouse tissues. Gel mobility shift assays demonstrated that Sp1 and Sp3 from Y-1, msc-1, and MIN-6 cells nuclear extracts bind the GC-boxes within the tescalcin proximal promoter. Bisulfite sequencing analysis of tescalcin CpG island revealed that it is differentially methylated in male and female mouse embryonic gonads, and that hypermethylation of this region represses expression of tescalcin in the β-TC3 cell line. ^ The major tescalcin mRNA encodes a protein with 214 amino acids that contains a consensus EF-hand Ca2+-binding domain and an N-myristoylation motif. The amino acid sequence of tescalcin is highly conserved among various species, and it showed the highest homology with calcineurin B homologous proteins 1 and 2, and calcineurin B. Western blot analysis using antibodies generated against the tescalcin protein confirmed its presence in specific mouse tissues and cell lines. Immunohistochemical analysis of mouse embryos confirmed the pattern of expression of tescalcin mRNA in fetal testis. Using pull-down assays, glyceraidehydes-3-phosphate dehydrogenase was identified as an interacting and potential functional partner of tescalcin. ^ The identification and characterization of tescalcin as a novel embryonic testicular marker will contribute to the elucidation of the genetic pathways involved in testis development and likely to the understanding of pathological conditions such as sex reversal and infertility. ^

Systematic review and meta-analysis of diagnostic accuracy of percutaneous renal tumour biopsy

Funding/Support and role of the sponsor: None.

Systematic review and meta-analysis of diagnostic accuracy of percutaneous renal tumour biopsy

Funding/Support and role of the sponsor: None.

Refining the diagnosis and EGFR status of non-small cell lung carcinoma in biopsy and cytologic material, using a panel of mucin staining, TTF-1, cytokeratin 5/6, and P63, and EGFR mutation analysis.

INTRODUCTION: The dichotomization of non-small cell carcinoma (NSCLC) subtype into squamous (SQCC) and adenocarcinoma (ADC) has become important in recent years and is increasingly required with regard to management. The aim of this study was to determine the utility of a panel of commercially available antibodies in refining the diagnosis on small biopsies and also to determine whether cytologic material is suitable for somatic EGFR genotyping in a prospectively analyzed series of patients undergoing investigation for suspected lung cancer. METHODS: Thirty-two consecutive cases of NSCLC were first tested using a panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, 34betaE12, and a D-PAS stain for mucin, to determine their value in refining diagnosis of NSCLC. After this test phase, two further pathologists independently reviewed the cases using a refined panel that excluded 34betaE12 because of its low specificity for SQCC, and refinement of diagnosis and concordance were assessed. Ten cases of ADC, including eight derived from cytologic samples, were sent for EGFR mutation analysis. RESULTS: There was refinement of diagnosis in 65% of cases of NSCLC to either SQCC or ADC in the test phase. This included 10 of 13 cases where cell pellets had been prepared from transbronchial needle aspirates. Validation by two further pathologists with varying expertise in lung pathology confirmed increased refinement and concordance of diagnosis. All samples were adequate for analysis, and they all showed a wild-type EGFR genotype. CONCLUSION: A panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, and a D-PAS stain for mucin increases diagnostic accuracy and agreement between pathologists when faced with refining a diagnosis of NSCLC to SQCC or ADC. These small samples, even cell pellets derived from transbronchial needle aspirates, seem to be adequate for EGFR mutation analysis.

Enteropathogenic Escherichia coli O125:H6 triggers attaching and effacing lesions on human intestinal biopsy specimens independently of Nck and TccP/TccP2

Typical enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) employ either Nck, TccP/TccP2, or Nck and TccP/TccP2 pathways to activate the neuronal Wiskott-Aldrich syndrome protein (N-WASP) and to trigger actin polymerization in cultured cells. This phenotype is used as a marker for the pathogenic potential of EPEC and EHEC strains. In this paper we report that EPEC O125:H6, which represents a large category of strains, lacks the ability to utilize either Nck or TccP/TccP2 and hence triggers actin polymerization in vitro only inefficiently. However, we show that infection of human intestinal biopsies with EPEC O125:H6 results in formation of typical attaching and effacing lesions. Expression of TccP in EPEC O125:H6, which harbors an EHEC O157-like Tir, resulted in efficient actin polymerization in vitro and enhanced colonization of human intestinal in vitro organ cultures with detectable N-WASP and electron-dense material at the site of bacterial adhesion. These results show the existence of a natural category of EPEC that colonizes the gut mucosa using Nck- and TccP-independent mechanisms. Importantly, the results highlight yet again the fact that conclusions made on the basis of in vitro cell culture models cannot be extrapolated wholesale to infection of mucosal surfaces and that the ability to induce actin polymerization on cultured cells should not be used as a definitive marker for EPEC and EHEC virulence.

Characterization of cancer/testis antigen MAGE-A11 for immunotherapy of prostate cancer

Les antigènes testiculaires du cancer sont des cibles idéales pour l’immunothérapie du cancer car ce sont des protéines immunogéniques dont l’expression est restreinte aux cellules germinales et au cancer. Le but de cette étude est d’évaluer le potentiel de MAGE-A11, un antigène testiculaire du cancer, comme cible pour développer un vaccin contre le cancer de la prostate. Pour ce faire, l’anticorps monoclonal 5C4 qui a la capacité de reconnaître la présence de MAGE-A11 dans les tissus fixés et inclus en paraffine a été produit. De plus, l’expression de MAGE-A11 a été analysée sur plusieurs lignées de cellules cancéreuses. Il a été démontré que MAGE-A11 est exprimé dans plusieurs types de cancers notamment dans le cancer du côlon et du cerveau. Finalement, nous avons identifié trois épitopes du CMH classe II HLA-DR1 dans la protéine MAGE-A11 confirmant ainsi l’immunogénicité de cet antigène et son potentiel comme cible pour l’immunothérapie du cancer.