As a natural anti-cancer alkaloid extracted from Amaryllidaceae, lycorine shows various biological effects on tumor cells. The survival rate of HL-60 cells exposed to lycorine was decreased in a dose-dependent manner with 1 lM as the 50% inhibitory concentration (IC50), cell growth was slowed down by arresting cell cycle at G2/M phase, and cell regeneration potential was inhibited. HL-60 cells exhibited typical apoptotic morphological changes, apoptotic DNA ''ladder'' pattern, and sub-G1 peak in cell phase distribution, showing apoptosis of HL-60 cells. To further understand the apoptotic molecular mechanism of lycorine on HL-60 cells, caspase activity was tested by colorimetric assay, and the expression of Bcl-2 and Bax proteins was examined by Western blotting. The increase of caspase-8, -9, -3 activities demonstrated that caspase was a key mediator of apoptotic pathways induced by lycorine. Under-expression of Bcl-2 and increase of Bax:Bcl-2 ratio showed that Bcl-2 family proteins were involved in apoptosis. Our finding suggests that lycorine can suppress leukemia growth and reduce cell survival via arresting cell cycle and inducing apoptosis of tumor cells.

The p21-activated kinase 4 (PAK4) is sufficient to transform noncancerous mammary epithelial cells and to form tumors in the mammary glands of mice. The accumulated information suggests that PAK4 might be an oncogenic protein in breast cancer. In this study, we sought to identify the role for PAK4 in breast cancer progression. Immunohistochemical study revealed that high PAK4 expression is associated with larger tumor size, lymph node metastasis, and advanced stage cancer in 93 invasive breast carcinoma patients. Moreover, high PAK4 expression was significantly associated with poor overall and disease-free survival. PAK4 remained an independent adverse prognosticator after univariate and multivariate analysis. Ectopic expression of wild-type PAK4 in MDA-MB-231 cells activated PI3K/AKT signaling and resulted in the enhancement of the cell proliferation, migration, and invasion, whereas PAK4-induced effects were blocked by the PAK4 kinase inhibitor PF- 3758309, PAK4 siRNAs or the PI3K inhibitor LY294002. Furthermore, a kinase-active PAK4 (S474E) strongly induced PI3K/AKT activation, and promoted proliferation, migration and invasion in breast cancer cells. A kinase-inactive PAK4 KD (K350A/K351A) did partially upregulate PI3K/AKT, and promoted invasive phenotype. Taken together, these findings suggest that PAK4-activated PI3K/AKT signaling is both kinase-dependent and -independent, which contributes to breast cancer progression. Thus, our results imply that dual inhibition of PAK4 and PI3K/AKT signaling might be a potential therapeutic approach for breast cancer therapy.

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We report on the development of one-dimensional microfluidic bead arrays for rapid and quantitative molecular profiling of human cancer cells. This new bioanalytical platform integrates the rapid binding kinetics of suspension bead carriers, the multiplexing and encoding capabilities of gene/protein chips, and the liquid handling advantages of microfluidic devices. Using antibody-conjugated beads in a two-site "sandwich" format, we demonstrate that the proteomic contents of as few as 56 human lung epithelial cancer cells can be determined with high sensitivity and specificity. The results indicate that each cell contains approximately 6 x 10(5) copies of the tumor suppressor protein P53. We have further examined the expression changes of P53, c-Myc, and beta-Actin as a function of anticancer drug treatment and have validated these changes by using Western blotting. This ability to quantitatively analyze normal and diseased cells raises new possibilities in studying cancer heterogeneity and circulating tumor cells.

Human diploid cell strains (HDCSs), possessing identical chromosome sets known to be free of all known adventitious agents, are of great use in developing human vaccines. However it is extremely difficult to obtain qualified HDCSs that can satisfy the requirements for the mass production of vaccines. We have developed a new HDCS, Walvax-2, which we derived from the lung tissue of a 3-month-old fetus. We established primary, master and working cell banks successfully from reconstituted frozen cells. Observations during the concurrent propagation of Walvax-2 and MRC-5 cells revealed differences in terms of growth rate, cell viability and viral sensitivities. Specifically, Walvax-2 cells replicated more rapidly than MRC-5 cells, with Walvax-2 cells attaining the same degree of confluence in 48 hours as was reached by MRC-5 cells in 72 hours. Moreover, Walvax-2 cells attained 58 passages of cell doublings whereas MRC-5 reached 48 passages during this period. We also assessed the susceptibility of these cells to rabies, hepatitis A, and Varicella viruses. Analysis of virus titers showed the Walvax-2 cells to be equal or superior to MRC-5 cells for cultivating these viruses. Furthermore, in order to characterize the Walvax-2 cell banks, a series of tests including cell identification, chromosomal characterization, tumorigenicity, as well as tests for the presence of microbial agents, exogenous viruses, and retroviruses, were conducted according to standard international protocols. In conclusion, results from this study show that Walvax-2 cell banks are a promising cell substrate and could potentially be used for the manufacturing of HDCVs.

Breast reconstruction with transverse rectus abdominis myocutaneous (TRAM) flap is challenging in patients with low midline abdominal scar. In this study, we aimed to investigate the clinical feasibility of immediate breast reconstruction using single-pedicle TRAM (SP-TRAM) flaps in patients with low midline abdominal scar. There were 4 strict selection criteria: 1) presence at least 3 perforators on the pedicle side; 2) perforators with regional average flow velocity of >20 cm/s; 3) upper edge of the abdominal scar at least 4 cm from the umbilicus; and 4) scar age >1 year. Eight breast cancer patients with low midline abdominal scar (scar group) and 20 without (control group) underwent immediate breast reconstruction with SP-TRAM flaps consisting of zone I and III and zone II tissues. Flap complications, donor-site complications, and cosmetic results were compared between the two groups. All flaps survived and both groups presented similar flap and donor site complications, including fat necrosis, seroma, hematoma, infection, delayed wound healing, and abdominal hernia, and patients in both groups had similar aesthetic results (p > 0.05). Thus, the study demonstrated that breast reconstruction using SP-TRAM flap was a safe approach in carefully selected patients with low midline abdominal scar.

Studying the expression level of mRNA in living cells will offer tremendous opportunities for advancement in cell biology research, disease diagnostics, and drug discovery. In this paper, a molecular beacon (MB) specific for the important tumor suppressor gene p21 has been designed and synthesized. The fluorescence signal was detected in real-time after the MB entered the cytoplasm of nasopharyngeal carcinoma cells. After injecting the p21MB into nasopharyngeal carcinoma cell and p33-transfected nasopharyngeal carcinoma cell, the consistent increase of fluorescent signal intensity was detected in both cell lines, and maximum fluorescence intensity achieved in about 15 min. In about 4 min following microinjection, the fluorescence increasing rate was significantly different between these two cell lines, which indicate the different p21 mRNA expression levels. The results obtained in the real-time detection were also validated by RT-PCR. Analysis of the initial fluorescence increasing rate can efficiently reduce the side effect of enzyme and improve the accuracy in living cell mRNA detection. molecular beacon, p21 mRNA, nasopharyngeal carcinoma cell, living cell imaging, fluorescence increasing rate Cell's structural and functional characteristics are dependent on the specific complement of genes expresses. Many cancers and cardiovascular diseases are associated with changes in particular genes' structure or abnormal expression level of particular genes [1 -3] . Real-time monitoring the dynamics of mRNA expression can offer tremendous opportunities for advancement in cell biology, molecular biology, medical diagnostics, and drug discovery [4] . It has become clear that a chemistry reaction in a test tube would have different thermodynamic and kinetic properties of the same reaction in a living cell [5,6] . Current RNA analysis techniques, including RT-PCR, Northern-Blot, and in situ hybridization [7][8][9][10][11] , can provide gene expression information by studying purified RNA obtained from cell lysate samples or by studying RNA in fixed cells. But these methods cannot visualize the expression level of specific RNAs in living cells in real-time. Therefore, mRNA has to be observed in real-time and in its native environment with high sensitivity [6] . However, it is difficult to study mRNA in living cells for the complicated cellular environments.MBs are dual-labeled single-strand oligonucleotide probes, with a fluorophore at one end and a quencher at the other end [12,13] . In the absence of a complementary target, the stem-loop structure keeps these two moieties in close proximity, causing the fluorescence of the fluorophore to be quenched. In the presence of target nucleic acid sequence, the loop region forms a hybrid and opens the stem. The spatial separation of the fluorophore and the quencher leads to the restoration of fluorescence emission from the fluorophore. MBs can report the presence of specific nucleic acids with high sensitivity and excellent specificity, and have been

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