Human galectin-2: expression profiling by RT-PCR/immunohistochemistry and its introduction as a histochemical tool for ligand localization.

Sugar-encoded information of glyco-conjugates is translated into cellular responses by endogenous lectins. Galectins stand out against other lectin families due to their wide range of functions including cell adhesion, tissue invasion or growth regulation exerted at extracellular, membrane, cytoplasmic and nuclear sites. This remarkable versatility warrants close scrutiny of their emerging network, in this study with focus on homodimeric human galectin-2. We first detected presence of specific mRNA in various tissue types by processing post mortem and surgical specimens by RT-PCR protocols. Overlap of gene expression was noted with proto-type galectins-1 and -7 and also family members from the other two subgroups. To monitor expression on the level of protein a polyclonal anti-galectin-2 antibody was raised. Immunopositivity was semi-quantitatively assessed in sections of 209 human samples establishing an array both of normal tissues and samples with inflammation or benign/malignant growth. In general, positivity was predominantly epithelial without restriction of staining to certain tissue types, as fittingly indicated by our RT-PCR analysis. Staining was not limited to the cytoplasm but also included nuclear sites. To examine the suitability of the labeled lectin as a histochemical probe we biotinylated galectin-2 under activity-preserving conditions and introduced it to tissue profiling. Specific cytoplasmic staining proved the validity of the concept. Our results encourage systematic histopathologic studies by immuno- and lectin histochemistry, especially by adding galectin-2 as study object to galectin fingerprinting which has already yielded prognostic information on galectins-1, -3, -4 and -8 and hereby contributed to define functional overlap/divergence in this lectin family.

Critical review in the surgical pathology of carcinoma of the stomach.

Further to a thorough analysis of the management of the surgical specimen for gastric carcinomas, guidelines were defined following several recommendations including informative gross and microscopic descriptions associated to a final correct staging of the tumour, according to the TNM classification and must at least include tumour penetration, nodal or distant metastases. The Belgian working party for GI cancer debate on these data and present a check-list that would help pathologists.

[External auditory meatus adenocarcinoma]. / Un adénocarcinome du méat acoustique externe.

We report the case of a man presenting a deafness and a hemorrhagic ear discharge since one year. CT scanner and MRI reveal an invasive tumoral lesion of the external auditory meatus (EAM) expending into the posterior fossa. After surgery the diagnosis of high grade ceruminal gland adenocarcinoma is established whereas the malignancy was not obvious on earlier biopsy. Cancers arising in the EAM are uncommon and are essentially representating by squamous cell cancers and basal cell cancers. The precise diagnosis of a glandular tumor is a challenge for the pathologist because the limits between benign and malignant tumors are not obvious. Integration of clinical and radiological behavior and the histology of the tumor is necessary for a early diagnosis and a complete surgery.