Study on apoE gene polymorphism and subclasses of serum high density lipoprotein in type IV hyperlipidemia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>The aim of the study was to investigate apolipoprotein(apo) E polymorphism and its relationship with serum lipids and apolipoprotein, serum high density lipoprotein(HDL) subclasses in patients with type IV hyperlipidemia.</p><p><b>METHODS</b>apoE genotype was assayed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The subclasses of serum HDL in 103 patients with type IV hyperlipidemia and 146 normolipidemic subjects were determined by two-dimensional gel electrophoresis in conjunction with immunodetection method.</p><p><b>RESULTS</b>The apoE3/3 genotype frequency and allele epsilon 3 frequency were both the highest in the frequency distribution profiles of the type IV hyperlipidemia group and the control group. In type IV hyperlipidemia group, the genotype of apoE2 had higher serum HDL-C,apoE, HDL(2a) apoE/apoCIII ratio but lower TG/HDL-C,apoCIII, HDL(3c) levels when compared with the genotype of apoE(3) (P<0.05). In control group, the genotype of apoE(2) had higher serum TG, apoE levels and apoE/aopCIII ratio but lower HDL (3a) level when compared with the genotype of apoE(3) (P<0.05).</p><p><b>CONCLUSION</b>An association of allele epsilon 2 of apoE gene with the maturation of HDL in type IV hyperlipidemia was noted in the study.</p>

Impact of p16INK4A and p15INK4B on human hepatocellular carcinoma cell proliferation and apoptosis / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>Both tumor suppressor p16INK4A and p15INK4B are members of INK family of CDK inhibitor. Although the role of p16 has been well documented, the role of p15 and its signaling pathway remain less well studied. This study was aimed to assess the effect of p16 and p15 on hepatocarcinoma cell lines with different status of Rb gene.</p><p><b>METHODS</b>After identification of the genetic status of p16, p15 as well as Rb of human hepatocellular carcinoma (HCC) cell lines BEL7402, SMMC7721 with the use of multiple PCR, the eukaryotic expression p16 and p15 recombinants pXJ-p16 and pXJ-p15 were constructed, respectively. The existence of exogenous p16, p15 genes, and the expression of p16 and p15 were assayed by means of PCR and RNA dot blotting. Finally, the proliferation and apoptosis were studied by using MTT, colony formation assay and flow cytometry.</p><p><b>RESULTS</b>Neither deletion of p16 nor p15 was detected in the two cell lines. However, Rb exons 14-16 instead of exons 22-23 deletion existed in SMMC7721. The increased mRNA expression level of p16 was found in BEL7402-p16 and SMMC7721-p16, while increased mRNA expression level of p15 was found in BEL7402-p15. The endogenous p16 and p15 genes were transcripted at low level. The cell growth and colony formation were decreased in BEL7402-p15, compared with either mock cell BEL7402 or vector control cell BEL7402-pXJ. Also shown in this study were an altered G1 phase population from 37.7% to 43.6%, an S phase population from 22% to 13% (P<0.05), and a Sub G1 peak (apoptosis peak) in BEL7402-p15. Conversely, BEL7402-p16 with endogenous p16 gene showed neither difference in cell cycle population nor difference in colony formation rate, compared with control cell groups. Additionally, SMMC7721-p16 cell growth was not inhibited by exogenous p16 gene.</p><p><b>CONCLUSION</b>p15 significantly arrested cell proliferation and induced apoptosis in BEL7402 in vitro, and the function was not influenced by endogenous p15 gene. The inhibition of cell growth by p16 on HCC cells could be dependent on intact RB pathway.</p>

Relationship of APOE gene polymorphism with subclasses of serum high density lipoprotein in hyperlipidemia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate apolipoprotein E(apoE) polymorphism and its relationship with serum lipids and apolipoprotein, serum high density lipoprotein (HDL) subclasses in patients with hyperlipidemia(HL).</p><p><b>METHODS</b>APOE genotype was assayed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The subclasses of serum HDL in 112 patients with hyperlipidemia and 73 healthy subjects were determined by two-dimensional gel electrophoresis in conjunction with immunodetection method.</p><p><b>RESULTS</b>APOE3/3 genotypes and allele epsilon3 frequency in HL group and control group were both the highest. In HL group, the genotype of APOE2 had higher serum APOE/CIII ratio and lower HDL3b levels, compared with the genotype of APOE3 (P<0.05). In control group, the genotype of apoE2 had higher serum triglycerides, APOE levels and APOE/CIII ratio, compared with the genotype of APOE3 and APOE4 (P<0.05).</p><p><b>CONCLUSION</b>Polymorphism of APOE gene may relate to the distribution of HDL particles.</p>