Monitoring glycosylation metabolism in brain and breast cancer by Raman imaging.

We have shown that Raman microspectroscopy is a powerful method for visualization of glycocalyx offering cellular interrogation without staining, unprecedented spatial and spectral resolution, and biochemical information. We showed for the first time that Raman imaging can be used to distinguish successfully between glycosylated and nonglycosylated proteins in normal and cancer tissue. Thousands of protein, lipid and glycan species exist in cells and tissues and their metabolism is monitored via numerous pathways, networks and methods. The metabolism can change in response to cellular environment alterations, such as development of a disease. Measuring such alterations and understanding the pathways involved are crucial to fully understand cellular metabolism in cancer development. In this paper Raman markers of glycogen, glycosaminoglycan, chondroitin sulfate, heparan sulfate proteoglycan were identified based on their vibrational signatures. High spatial resolution of Raman imaging combined with chemometrics allows separation of individual species from many chemical components present in each cell. We have found that metabolism of proteins, lipids and glycans is markedly deregulated in breast (adenocarcinoma) and brain (medulloblastoma) tumors. We have identified two glycoforms in the normal breast tissue and the malignant brain tissue in contrast to the breast cancer tissue where only one glycoform has been identified.

Juvenile xanthogranuloma: a congenital giant form leading to a wide atrophic sequela.

Juvenile xanthogranuloma is the most common non-Langerhans cell histiocytosis of infancy and childhood. It is a benign disorder that usually regresses spontaneously, more often without or with limited skin changes. The clinical features are very pleomorphic and recognition of the atypical presentations should facilitate the diagnosis. We report a 9-month-old boy who had an extensive, atrophic lesion on the proximal thigh that followed the course of the congenital giant form. The large size of the lesion does not alter the clinical course or result in extracutaneous involvement, which remains rare. However, uncommon clinical presentations raise the problem of differential diagnosis, requiring biopsy to eliminate other tumors with a less favorable prognosis.