Tanshinones suppress AURKA through up-regulation of miR-32 expression in non-small cell lung cancer.

Tanshinone is the liposoluble constituent of Salia miltiorrhiza, a root used in traditional herbal medicine which is known to possess certain health benefits. Although it is known that tanshinones, including tanshinone I (T1), tanshinone IIA (T2A), and cryptotanshinone (CT), can inhibit the growth of lung cancer cells in vitro, the mechanism under which they act is still unclear. AURKA, an oncogene, encodes a serine-threonine kinase which regulates mitotic processes in mammalian cells. Here, we reported that tanshinones mediate AURKA suppression partly through up-regulating the expression of miR-32. We found that tanshinones could inhibit cell proliferation, promote apoptosis, and impede cell-cycle progression, thus performing an antineoplastic function in non-small cell lung cancer (NSCLC). Additionally, we demonstrated that tanshinones attained these effects in part by down-regulating AURKA, corroborating previous reports. Our results showed that in NSCLC, similar effects were obtained with knock-down of the AURKA gene by siRNA. We also verified that AURKA was the direct target of miR-32. Collectively, our results demonstrated that tanshinones could inhibit NSCLC by suppressing AURKA via up-regulating the expressions of miR-32 and other related miRNAs.

MicroRNA-34a inhibits the proliferation and promotes the apoptosis of non-small cell lung cancer H1299 cell line by targeting TGFßR2.

MicroRNAs (MiRNAs) are small non-coding RNA molecules which act as important regulators of post-transcriptional gene expression by binding 3'-untranslated region (3'-UTR) of target messenger RNA (mRNA). In this study, we analyzed miRNA-34a (miR-34a) as a tumor suppressor in non-small cell lung cancer (NSCLC) H1299 cell line. The expression level of miR-34a in four different NSCLC cell lines, H1299, A549, SPCA-1, and HCC827, was significantly lower than that in the non-tumorigenic bronchial epithelium cell line BEAS-2B. In human NSCLC tissues, miR-34a expression level was also significantly decreased in pT2-4 compared with the pT1 group. Moreover, miR-34a mimic could inhibit the proliferation and triggered apoptosis in H1299 cells. Luciferase assays revealed that miR-34a inhibited TGFßR2 expression by targeting one binding site in the 3'-UTR of TGFßR2 mRNA. Quantitative real-time PCR (qRT-PCR) and Western blot assays verified that miR-34a reduced TGFßR2 expression at both mRNA and protein levels. Furthermore, downregulation of TGFßR2 by siRNA showed the same effects on the proliferation and apoptosis as miR-34a mimic in H1299 cells. Our results demonstrated that miR-34a could inhibit the proliferation and promote the apoptosis of H1299 cells partially through the downregulation of its target gene TGFßR2.

[Production of mature red blood cell by using peripheral blood mononuclear cells].

Most protocols for in vitro producing red blood cells (RBC) use the CD34(+) cells or embryonic stem cells from cord blood, bone marrow or peripheral blood as the start materials. This study was purposed to produce the mature RBC in vitro by using peripheral blood mononuclear cells as start material. The peripheral blood mononuclear cells (PBMNC) were isolated from buffy coat after blood leukapheresis, the mature red blood cells (RBC) were prepared by a 4-step culture protocol. The results showed that after culture by inducing with the different sets of cytokines and supporting by mouse MS-5 cell line, the expansion of PBMNC reached about 1000 folds at the end of the culture. About 90% of cultured RBC were enucleated mature cells which had the comparable morphological characteristics with normal RBC. Colony-forming assays showed that this culture system could stimulate the proliferation of progenitors in PBMNC and differentiate into erythroid cells. The structure and function analysis indicated that the mean cell volume of in vitro cultured RBC was 118 ± 4 fl, which was slight larger than that of normal RBC (80-100 fl); the mean cell hemoglobin was 36 ± 1.2 pg, which was slight higher than that of normal RBC (27-31 pg); the maximal deformation index was 0.46, which approachs level of normal RBC; the glucose-6-phosphate dehydrogenase and pyrurvate kinase levels was consistant with young RBC. It is concluded that PBMNC are feasble, convenient and low-cost source for producing cultured RBC and this culture system is suitable to generate the RBC from PBMNC.

miR-150, p53 protein and relevant miRNAs consist of a regulatory network in NSCLC tumorigenesis.

microRNAs (miRNAs) are a class of non-coding small RNAs that act as negative regulators of gene expression by binding to the 3'-untranslated region (3'-UTR) of target mRNAs. Tumor protein p53, a transcriptional factor, plays an important role in the progression of tumorigenesis. miR-150 was the only miRNA predicted to target 3'-UTR of p53 by Targetscan. In order to investigate the function of miR-150, p53 and relevant miRNAs in non-small cell lung cancer (NSCLC), we constructed two expression vectors of p53 (pcDNA3.1-p53 and pcDNA3.1-p53-3'-UTR) and two report vectors (pGL3-p53-3'-UTR and pGL3-p53-3'-mUTR). The activity of luciferase transfected with miR-150 mimics was lower by 30% when compared to that of the miRNA-negative control (miRNA-NC). Moreover, the p53 protein was downregulated by at least 50% when miR-150 mimics were cotransfected with pcDNA3.1-p53-3'-UTR when compared to miRNA-NC. We also determined the expression of miR-150 and p53 in NSCLC patient tissue samples. The expression of miR-150 in T2 stage tissue samples was higher than that in T1 stage tissue samples. The corresponding target gene p53 was correlated with miR-150 expression. In the present study, we further analyzed the cell cycle distribution. The cells transfected with pcDNA3.1-p53 were significantly arrested in the G1 phase when compared to the control cells. When miR-150 mimics were cotransfected with pcDNA3.1-p53-3'-UTR, the percentage of cells in the G1 phase was significantly lower by 4% when compared to miRNA-NC. To identify miRNAs that are regulated by the p53 protein, qRT-PCR was performed after pcDNA3.1-p53 transfection. miR-34a, miR-184, miR-181a and miR-148 were upregulated significantly. However, there was no distinct difference in the expression of miR-10a, miR-182 and miR-34c. Our results showed that miR-150 targets the 3'-UTR of p53, and p53 protein promotes the expression of miRNAs which affect cell cycle progression. These findings suggest that miR-150, p53 protein and relevant miRNAs are members of a regulatory network in NSCLC tumorigenesis.

[To identify a novel HLA-DRB1 allele in Chinese by sequencing].

OBJECTIVE: To identify a novel HLA-DRB1 allele in Chinese. METHODS: A novel HLA-DR allele was detected by PCR-SSP and SBT in a patient with leukemia. RESULTS: The sequence of the novel allele was different from all other known alleles. The novel allele differed from the closet matching allele HLA-DRB1*1404 by one nucleotide substitution in exon 2, at position 33 T>C, this resulted in an amino acid change from Tyr to His at codon 17. CONCLUSION: The novel allele is confirmed as a new HLA allele and it was officially named HLA-DRB1*1461 by WHO Nomenclature Committee in May, 2006.

[Investigation on induced expansion of erythroid cells from cord blood CD34(+) cells in vitro].

This study was aimed to investigate a beneficial approach for resolving the deficiency of blood source, preventing the infection resulting from blood transfusion and overcoming the knotty match of patients with rare blood group by using massive expansion of erythroid cells from cord blood CD34(+) cells in vitro. The CD34(+) cells from human cord blood were cultured in serum-free medium supplemented with stem cell factor (SCF), interleukin-3 (IL-3) and erythropoietin (EPO) for 1 week, then expansion and differentiation of CD34(+) cells into erythroid cells were supported by co-culture with human mesenchymal stem cells (MSCs) derived from bone marrow for 2 weeks. The results indicated that after culture for 23 days, the expansion multiple of total cell number reached 2.52 x 10(5), and over 95% of these cells were erythroid cells as compared with less than 1% of myelomonocytic (CD14(+) or CD15(+)) cells and megakaryocytic (CD41(+)) cells. However, the culture system without MSC support was significantly disadvantaged both in expansion ability and ratio of erythroid cells when compared with MSC supporting system. It is concluded that the erythroid cells can be produced from CD34(+) cells in large scale by culturing in the system comprised of cytokine sets and MSC feeders, in which MSCs can support the proliferation and differentiation of erythroid cells.

[A recombination event occurring between HLA-B and DRB1 loci within a Chinese Han family].

OBJECTIVE: To investigate a recombination event occurring between the HLA-B and DRB1 loci in a Chinese family with a leukemia patient. METHODS: HLA class I (-A and -B) low resolution typing was carried out by polymerase chain reaction-sequence specific oligonucleotide, PCR-SSO). HLA class II low resolution typing was performed by PCR-sequence specific primer (PCR-SSP). And HLA class I and II high resolution typing was done by sequencing-based typing (SBT). Then the recombination event was analyzed by family study. RESULTS: The 2 haplotypes of the patient were A*3101-B*1301-DRB1*0701 and A*3303-B*4403-DRB1*1302. His father's 2 haplotypes were A*3001-B*1302-DRB1*0701 and A*3101-B*1301-DRB1*1501. Family study demonstrated that the HLA-A*3101-B*1301 was from one of his father's chromosome and the DRB1*0701 was from the other chromosome of his father. So the result indicated that the recombination event occurred between the HLA-B and -DRB1 loci during meiosis of his father and resulted in a new HLA haplotype that was transferred to the son. CONCLUSION: A HLA-B/DR recombination event occurring between the HLA-B and -DRB1 loci has been found in a Chinese family, which may help further study of the mechanism of HLA recombination.