Application Of The Ap-pcr Dna Fingerprints Of Separation Of Differentially Expressed Genes In Non-small Cell Lung Cancer

Initiation and progression of non-small cell lung cancer are accompanied and probably caused by a variety of genetic defects. Detection and characterisation of genetic alteration would provide information of carcinogenesis. Using a recent developed polymerase chain reaction technology, it is now feasible to determine whether novel oncogenes are frequently amplified in human non-small cell lung cancer. This technique, denoted arbitrarily primed-PCR (AP-PCR), uses a single primer of arbitrary sequence and generates a DNA fingerprint that can display multiple qualitative and quantitative differences between closely related genomes. We have used an arbitrarily 20 bases primed PCR and obtained six bands that were more intense in the tumour DNA fingerprint as compared to the one from the corresponding normal lung DNA. These six bands were excised from 2% agarose gel, cloned, and four bands after cloning were sequenced. Comparison of the each one of four 429 bp DNA sequences with GenBank and EMBL data bases displayed no homology with other present sequences. To determine the copy number of the polymorphic DNA in the tumour samples; the cloned band 8Tdf was used as a probe for Southern blot of tumour/normal pairs. The result confirmed that the DNA sequence was amplified in 5 of 9 non-small cell lung cancer, samples suggesting that the fragments probably associated with tumorigenesis and development of non-small cell lung cancer, the precise function of these fragments is currently unknown and need to be further investigated.