Presence and Absence of Chondroitin Sulfate in Lung Tissues as a Potential Diagnostic Marker of Lung Cancer.
Maristela Peres Rangel, Joao Roberto Maciel Martins, Vanessa Karen de Sa, Edwin Roger Parra Cuentas, Eloisa Olivieri, Vera Luiza Capelozzi. Faculdade de Medicina da Universidade de São Paulo, Brazil; Universidade Federal de São Paulo, São Paulo, Brazil; Hospital A.C. Camargo, São Paulo, Brazil
Background: The relationship between the extracellular matrix(ECM) components and cancer cells have an important role on cancer development and progression.Between the most important molecules present on the ECM are the glycosaminoglycans(GAGs) and studies have reported that they have different behaviours when in the presence of malignant tissues.The aim of this study was to analyse the GAGs concentration in normal and tumoral areas of patients with lung cancer(LC).
Design: Normal and tumoral tissue specimens were obtained from 41 patients with LC(stages I until IIIB).Sulfated GAG chains(heparan, dermatan and chondroitin sulfate – HS, DS and CS)were obtained after incubation with a proteolytic enzyme.GAGs were precipitated with ethanol and the pellet was centrifugated, dried and dissolved in DNAse(5 μl/mg).The different types of sulfated GAGs and their concentration in the lung samples were identified after gel electrophoresis in diaminopropane buffer.
Results: We observed a distinct profile of GAG between normal and tumoral areas.HS showed significantly higher concentration in tumoral than in normal areas(p=0.02)(FIG 1A).This data correlated with the different histologic types.The adenocarcinomas had higher amounts of HS than squamous cell carcinoma specimens(p=0.02)(FIG 1B).One hundred % of tumoral areas presented CS while the normal areas did not(p<0.0001)(FIG 1C).
Conclusions: The presence of CS and higher concentrations of HS in patients with lung cancer suggest a possible role of these GAGs in this pathological condition, but more importantly provide a potential biochemical marker for differentiating normal from lung cancer patients.The correlation between the histologic types and the amounts of HS provide a possible role of this GAG on the development of tumor agressiveness considering that one of its functions is to bind itself to growth factors and regulate their action.However, further studies are needed to determine whether or not these GAGs concentrations are able to be diagnostic/prognostic markers of LC and what is their role regarding the histologic types.
Tuesday, March 1, 2011 1:00 PM
Poster Session IV # 253, Tuesday Afternoon