[Construction and characterization of frozen tissue microarray with defined histological regions of gastric specimens].

BACKGROUND & OBJECTIVE: In the genome-wide investigation of cancers, high-throughput downstream approach is in urgent need to validate the candidates of cancer associated genes screened by cDNA microarrays. To meet this need, frozen tissue microarrays were constructed using defined histological regions of gastric tissues and their general features were characterized by multiple parameters.

METHODS

By the use of self-designed tissue arraying system, 0.7 mm tissue spots were cored from defined histological regions of gastric tissues and orderly filled into the array-recipient OCT(optimal cutting temperature compound) block in the density of 30 spots/0.7 cm(2) or 49 spots/cm(2). The spots of tissue array was characterized histologically, and then by the methods of immunohistochemistry(IHC) and mRNA-in situ hybridization(RISH) for casepase-3.

RESULTS

The spot sampling was performed accurately, and the morphology of most tissue spots was kept well after multiple steps of processing. Immunohistochemical staining revealed that casepase-3 was produced in 100.0% of noncancerous gastric mucosa, 66.7% of neoplastic mucosa and 20.0% in cancer tissues. The results of RISH were well coincided with that of ICC in the rates of 90.0%, 60.0%, and 15.4%.

CONCLUSION

The frozen tissue array described in this study allows rapid and precise molecular analyses of various gastric lesions in the same experimental conditions. It would be a novel downstream tool in genome-wide study of gastric cancers both in screening and functional elucidation of candidate gastric cancer associated genes.