Identification of novel metastasis associated genes MAG-1 and MAG-2 / 中国肺癌杂志

<p><b>BACKGROUND</b>To isolate and identify the genes related to cancer metastasis by comparison of two cell strains with different metastasis potentials subcloned from human lung giant cell carcinoma cell line.</p><p><b>METHODS</b>Suppression subtractive hybridization (SSH) was used to compare the levels of gene expression between the two cell strains and SSH library was constructed. After screening the library by gene chip, the expressed sequence tags (ESTs) with different expressing level were sequenced and blasted with GenBank.</p><p><b>RESULTS</b>Seventy-nine genes were obtained that were expressed much higher in PLA-801D than in PLA-801C, including two full-length cDNA. GenBank Accession numbers of the two cDNA, named MAG-1 and MAG-2, were BC006236 and BC002420, the 8.5 kb MAG-1 gene was composed of four exons and located on the chromosome of 4q21. The MAG-2 gene, which was made up by 9 exons, had a length of 5.2 kb and its location was 2q35. Both sequences had open reading frames (ORF) and promoters before the theoretical transcription start points. Using special software, the secondary structure of theoretical products of the two cDNAs was prognosticated, α-helix was the main proportion, but β-pleated sheet and random coil were also included.</p><p><b>CONCLUSIONS</b>The expression of MAG-1 and MAG-2 has significant differences in these two cell strains, so they might impact tumor metastasis in some ways that are still uncharted.</p>

Mitochondrial DNA deletion on the growth and invasiveness of human lung cancer cells / 第三军医大学学报

Objective To explore the relationship between mitochondrial DNA deletion and malignant phenotypes of human lung cancer cells. Methods Two rho? derivatives of 95C and 95D were generated by treating the cultured cells with ethidium bromide. Agarose colony formation assays and Transwell invasion assays were carried out to detect the phenotypes of colony formation and invasiveness of the cultured cells, respectively. Cell growth was determined by MTT. Results The partially mtDNA-deleted cells exhibited stronger capacity of colony formation and invasiveness, and faster growth rates than their respective parental cell lines. Conclusion Mitochondrial DNA deletion might play a role in the formation of malignant phenotypes of human lung cancer.

Preparation and clinical application of the monoclonal antibodies against the human O6 -methylguanine-DNA methyltransferase / 军事医学科学院院刊

Objectives:To establish hybridomas secreting monoclonal antibodies(McAbs) against O6-methylguanine-DNA methyltransferase(MGMT) and to observe the relationship between MGMT expression and clinical responses to ACNU and BCNU in human brain tumors.Methods:The hybridomas were established by cell fusion.MGMT expression in 60 glioma specimens was detected by means of immunohistochemical assay.Results: Seven hybridomas secreting McAbs against MGMT were obtained.Thirty tumor specimens had no detectable or low level of MGMT expression(Mer-), while 30 specimens had high level of MGMT expression(Mer+). The Mer- patients showed more sensitive to ACNU and BCNU than the Mer+ patients.Conclusions: The high specific hybridomas secreting monoclonal antibodies(McAbs) against MGMT were established.The preliminary study indicated that MGMT negative tumors were sensitive to ACNU and BCNU, whereas MGMT positive ones were more resistant to nitrosourea drugs.