ID3, TCF3 and MYC genes mutation analyses in Chinese Burkitt lymphoma / 临床与实验病理学杂志

Purpose To investigate the mutations of ID3,TCF3 and MYC genes in Chinese Burkitt lymphoma and discuss their significance.Methods Total DNA was extracted from tumor tissues of 32 patients with Burkitt lymphoma,then the DNA was amplified by polymerase chain reaction (PCR),and the products of PCR were sequenced directly with Sanger sequencing methods.Results The mutation rates of ID3 and TCF3 genes were 35.5％ (11/31) and 18.8％ (6/32) respectively.The mutation rate of MYC was 50％.The mutation rates of MYC exon 1,MYC exon 2 and MYC exon 3 were 3.3％ (1/30),50％ (15/30) and 7.7％ (2/26) respectively.Conclusion Recurrent mutations of the ID3,TCF3 and MYC genes in Chinese Burkitt lymphoma were identified by Sanger sequencing.For TCF3 gene,a novel mutation c.2202G ＞ C p.L569V was found in three cases.In two cases,a novel mutation of c.1070A ＞G p.G182D was found in MYC gene.

Spontaneous senescence in malignant tumor cell lines / 肿瘤

Objective:To explore whether spontaneous sene-scence widely existed in malignant tumor cells. Methods:Sene-scence-associated beta-galactosidase (SA-β-Gal) staining kit was used to detect the activity of SA-β-Gal in ten different malignant tumor cell lines before and after serum deprivation. Results:SA-β-Gal was expressed in some cells of 10 malignant tumor cell lines during exponential growth phase without any treatment. However, the percentage of senescent cells was significantly different among them, the lowest expression was observed in HeLa cell line (0.65%), and the highest expression was seen in HepG2 cell line (3.69 %, F=13.006, P= 0.000). Furthermore, not all the SA-β-Gal positive aging cells were polyploid cells. After 24-h serum deprivation, the number of SA-β-Gal positive cells was significantly increased (P=0.001). Conclusion:These findings indicate that immortal malignant tumor cell lines could undergo spontaneous senescence but the level was different between various cell lines. Short-term serum de-privation significantly increased the percentage of aging cells indicating that serum deprivation-induced cell senescence may be a rapid, easy, and effective way for anti-tumor therapy.