Molecular markers for reinforcement of histological subclassification of neuroendocrine lung tumors.

The degree of malignancy of neuroendocrine lung tumors (NEs) increases in this order: from typical carcinoids (TCs) through atypical carcinoids (ACs) to large cell neuroendocrine carcinomas (LCNECs) and small cell lung carcinomas (SCLCs). However, histological classification has sometimes proved difficult. We here investigated loss of heterozygosity (LOH) using eight microsatellite markers and expression of p53, Bcl-2 and Bax proteins using immunohistochemical methods in 57 NEs (19 TCs, 5 ACs, 14 LCNECs and 19 SCLCs), looking for objective genetic markers to distinguish between subtypes.

A role for the pituitary tumor-transforming gene in the genesis and progression of non-small cell lung carcinomas.

Background: The product of the pituitary tumor-transforming gene (PTTG) inhibits chromatid separation, which is considered to promote chromosome instability, especially in the absence of the p53 gene product, and also induces basic fibroblast growth factor (bFGF) production. Its expression and these variables in primary non-small cell carcinomas (NSCLCs) of known p53 status were examined.

Materials And Methods: Comparative genomic hybridization analysis of 78 lesions revealed a wide range of total (gain + loss) chromosomal imbalance numbers (tCINs).

Differentiation of Various Cell Types during Fruiting Body Formation of Dictyostelium Discoideum.

The processes of differentiation of the presumptive cells (prespore and prestalk cens) into mature spores, stalk and basal-disc cells in Dictyotelium discoideum was investigated. The number of stalk and disc cells in pre-labeled culminating cell masses was estimated by determining the radioactivity of the undissociable fraction separated by filtration from the dissociable fraction containing presumptive cells and spores. Changes in the proportion of amoeboid cells stainable with fluorescein-conjugated antispore serum and encapsulated spores were also followed in the dissociable fraction.