Germline mutations of TP53 gene among Chinese families with high risk for breast cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To evaluate the role of germline mutations of TP53 gene among a Chinese population with high risk for breast cancer.</p><p><b>METHODS</b>A total of 81 BRCA-negative breast cancer probands from cancer families were analyzed using targeted capture and next-generation sequencing. Candidate mutations were verified with Sanger sequencing. Co-segregation analyses were carried out to explore the likely pathogenicity of the mutation.</p><p><b>RESULTS</b>Of the 81 BRCA-negative patients, 3 exonic mutations in the TP53 gene were identified in 3 breast cancer patients. Of these, 2 mutations were previously reported and 1 was novel. One family with TP53 mutation has met the criteria for Li-Fraumeni syndrome (LFS) and accounted for 9.1% of all families who fulfilled the diagnostic criteria for LFS. Two of the carriers were diagnosed with breast cancer under the age of 30, and have accounted for 11.8% (2/17) of all very young (≤30 years) breast cancer patients in our study.</p><p><b>CONCLUSION</b>The TP53 germline mutation is more common in Chinese population with a high risk for breast cancer than previously thought. TP53 gene mutation screening should be considered particularly for patients with a family history of LFS and very young age of onset.</p>

Abilities Training in PBL / 中华医学教育探索杂志

The abilities of self-study,thinking and communication are much more emphasized in the problem based learning(PBL)than in the conventional curriculum.From the view of the inherent relationship between the ability training and PBL,this paper probes into the characteristics of PBL to find the way of fitting the situation of our country.It is essential to the successful teaching and training more high quality students.

Effects of lipopolysaccharide binding protein on activation of p38 signaling pathway induced by LPS in macrophages / 中国病理生理杂志

AIM: To investigate the regulatory effects of lipopolysaccharide binding protein(LBP)on activation of p38 signaling pathway induced by lipopolysaccharide(LPS)in alveolar macrophages. METHODS: The LBP from actue phase rat serum was purified by ammonium sulphate precipitation, Bio-Rex70 resin and the MonoQ column. Rat alveolar macrophages were exposed to LPS (0 01 mg/L or 1 mg/L) the various concentrations of LBP(0 mg/L, 0 01 mg/L, 0 1 mg/L,1 mg/L and 10 mg/L) Western blotting were used to detect phospho-p38 in alveolar macrophages RESULTS: SDS-PAGE analysis indicated that the purified preparation of rat LBP showed homogeneity and the molecular weight was 60 kD.The binding of lipopolysaccharide to mononuclear cells were enhanced by purified rat LBP. Stimulation of rat alveolar macrophages with LPS at concentration of 0.01 mg/L was LBP dependent. LBP at concentrations up to 1 mg/L was able to increase the activation of p38. However , when LBP concentrations were further increased to 10 mg/L, the phosphorylation levers of p38 were lower as compared with that in the presence of 1 mg/L. Stimulation of rat alveolar macrophages with LPS at concentrations of 1 mg/L was LBP-independent. CONCLUSION: The activation of p38 induced by LPS at lower concentration(0.01 mg/L ) was LBP-dependent, meanwhile, LPS at higher concentration (1 mg/L ) was LBP-independent.

Rab27A is involved in malignant phenotypes in human breast cancer cells by regulating the expression of related genes / 中国癌症杂志

Background and purpose:Rabs are members of Ras-related small GTPase superfamily. Rab27A is a unique member in the Rab family and has specific implications in human genetic diseases. We studied the potential role of Rab27A in proliferation, distribution of cell cycle, apoptosis and invasion of breast cancer cells and its mechanism(s). Methods:The eukaryotic expression vector containing Rab27A open reading frame (ORF) pcDNA3.1(+) - Rab27A was constructed and transfected into MDA-MB-231 breast cancer cells. Then we detected the changes in terms of cell growth, cell cycle distribution, apoptosis and in vitro invasion capability before and after transfection. We also applied RT-PCR to investigate the molecular basis.Results:① The expression of Rab27A was increased as invasive and metastatic ability increased in four human breast cancer cell lines. ② Overexpression of Rab27A can promote breast cancer cells to grow faster, increase the proportion of S phase cells, avoid apoptosis and invade in vitro. ③ Rab27A transfectants constitutively enhanced the expression of Cyclin D1, MMP-7 and MMP-9 in MDA-MB-231 cell lines, on the contrary, that of p16 were down-regulated constitutively. Reduced Rab27A expression by RNAi down-regulated the expression of Cyclin D1, MMP-7 and MMP-9, and up-regulated p16 expression.Conclusions:Rab27A can stimulate breast cancer cells to proliferate, increase the proportion of cells in S phase,avoid apoptosis and invade in vitro by regulating the expression of Cyclin D1, MMP-7, MMP-9 and p16.