Novel insights into cell cycle regulation of cell fate determination / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The stem/progenitor cell has long been regarded as a central cell type in development, homeostasis, and regeneration, largely owing to its robust self-renewal and multilineage differentiation abilities. The balance between self-renewal and stem/progenitor cell differentiation requires the coordinated regulation of cell cycle progression and cell fate determination. Extensive studies have demonstrated that cell cycle states determine cell fates, because cells in different cell cycle states are characterized by distinct molecular features and functional outputs. Recent advances in high-resolution epigenome profiling, single-cell transcriptomics, and cell cycle reporter systems have provided novel insights into the cell cycle regulation of cell fate determination. Here, we review recent advances in cell cycle-dependent cell fate determination and functional heterogeneity, and the application of cell cycle manipulation for cell fate conversion. These findings will provide insight into our understanding of cell cycle regulation of cell fate determination in this field, and may facilitate its potential application in translational medicine.

Helicobacter pylori inhibited cell proliferation in human periodontal ligament fibroblasts through the Cdc25C/CDK1/cyclinB1 signaling cascade

PURPOSE: Several studies have shown that the oral cavity is a secondary location for Helicobacter pylori colonization and that H. pylori is associated with the severity of periodontitis. This study investigated whether H. pylori had an effect on the periodontium. We established an invasion model of a standard strain of H. pylori in human periodontal ligament fibroblasts (hPDLFs), and evaluated the effects of H. pylori on cell proliferation and cell cycle progression. METHODS: Different concentrations of H. pylori were used to infect hPDLFs, with 6 hours of co-culture. The multiplicity of infection in the low- and high-concentration groups was 10:1 and 100:1, respectively. The Cell Counting Kit-8 method and Ki-67 immunofluorescence were used to detect cell proliferation. Flow cytometry, quantitative real-time polymerase chain reaction, and western blots were used to detect cell cycle progression. In the high-concentration group, the invasion of H. pylori was observed by transmission electron microscopy. RESULTS: It was found that H. pylori invaded the fibroblasts, with cytoplasmic localization. Analyses of cell proliferation and flow cytometry showed that H. pylori inhibited the proliferation of periodontal fibroblasts by causing G2 phase arrest. The inhibition of proliferation and G2 phase arrest were more obvious in the high-concentration group. In the low-concentration group, the G2 phase regulatory factors cyclin dependent kinase 1 (CDK1) and cell division cycle 25C (Cdc25C) were upregulated, while cyclin B1 was inhibited. However, in the high-concentration group, cyclin B1 was upregulated and CDK1 was inhibited. Furthermore, the deactivated states of tyrosine phosphorylation of CDK1 (CDK1-Y15) and serine phosphorylation of Cdc25C (Cdc25C-S216) were upregulated after H. pylori infection. CONCLUSIONS: In our model, H. pylori inhibited the proliferation of hPDLFs and exerted an invasive effect, causing G2 phase arrest via the Cdc25C/CDK1/cyclin B1 signaling cascade. Its inhibitory effect on proliferation was stronger in the high-concentration group.

Anti-colorectal cancer effects of tripolinolate A from Tripolium vulgare / 中国天然药物

Tripolinolate A (TLA) is recently identified as a new compound from a halophyte plant Tripolium vulgare and has been shown to have significant in vitro activity against the proliferation of colorectal cancer and glioma cells. This study was designed to further investigate the effects of TLA on the proliferation of human normal cells, and the apoptosis and cell cycle in colorectal cancer cells, and the growth of tumors in the colorectal cancer-bearing animals. The data obtained from this study demonstrated that: 1) TLA had much less cytotoxicity in the human normal cells than the colorectal cancer cells; 2) TLA remarkably induced apoptosis in the human colorectal cancer cells and blocked cell cycle at G/M phase, and 3) TLA had significant anti-colorectal cancer activity in the tumor-bearing animals.

Effect of RAD18-siRNA on proliferation and chemotherapy sensitivity of human esophageal squamous cell carcinoma ECA-109 cells / 浙江大学学报·医学版

To investigate the effect of RAD18-siRNA on cell proliferation and chemotherapy sensitivity of esophageal squamous cell carcinoma (ESCC) ECA-109 cells.RAD18-siRNA was transfected into human ECA-109 cells by Lipofectamine 3000. Quantitative PCR and Western blot were performed to detect RAD18 and CyclinD1 expression; CCK-8 assay was used to determine cell proliferation and chemotherapy drug sensitivity; flow cytometry was used to determine cell cycle. Correlation between RAD18 and CyclinD1 mRNA expression was analyzed by Pearson's correlation.Compared with non-transfected cells, the expression of RAD18 in RAD18-siRNA group was significantly decreased (<0.05). The cell proliferation was inhibited (<0.05) and the cell number of G1 phase was increased, G2/M phase cells decreased (<0.05) in RAD18-siRNA group. After treatment with different concentrations of cisplatin or 5-FU, the survival rate of the two cell groups was reduced (all<0.05), and the IC50 of RAD18-siRNA group was significantly lower than that of non-transfected group (<0.05). The mRNA expression of RAD18 was positively correlated with CyclinD1 expression in ESCC tissues(=0.478,<0.01).Down-regulated expression of RAD18 can decrease the cell proliferation and increase chemo-sensitivity of ESCC cells, and CyclinD1 may participate in the process.

MiR-144 inhibits cell proliferation of renal cell carcinoma by targeting MTOR / 华中科技大学学报（医学）（英德文版）

MicroRNAs (miRNAs) modulate the expression of tumorigenesis-related genes and play important roles in the development of various types of cancers. It has been reported that miR-144 is dysregulated and involved in multiple malignant tumors, but its role in renal cell carcinoma (RCC) remains elusive. In this study, we demonstrated miR-144 was significantly downregulated in human RCC. The decreased miR-144 correlated with tumor size and TNM stage. Moreover, overexpression of miR-144 in vitro suppressed RCC cell proliferation and G2 transition, which were reversed by inhibition of miR-144. Bioinformatic analysis predicted that mTOR was a potential target of miR-144, which was further confirmed by dual luciferase reporter assay. Additionally, the examination of clinical RCC specimens revealed that miR-144 was inversely related to mTOR. Furthermore, knocking down mTOR with siRNA had the same biological effects as those of miR-144 overexpression in RCC cells, including cell proliferation inhibition and S/G2 cell cycle arrest. In conclusion, our results indicate that miR-144 affects RCC progression by inhibiting mTOR expression, and targeting miR-144 may act as a novel strategy for RCC treatment.

Absolute configuration of podophyllotoxone and its inhibitory activity against human prostate cancer cells / 中国天然药物

Podophyllotoxone (1) was isolated from the roots of Dysosma versipellis. The structure was determined by spectroscopic analysis in combination with single-crystal X-ray analysis. The absolute configuration of compound 1 was assigned based on the Flack parameter. It showed significant inhibitory activities against human prostate cancer cells PC3 and DU145 with IC50 values being 14.7 and 20.6 μmol·L(-1), respectively. It also arrested the cells at G2/M phase. Tubulin polymerization assay showed that it inhibited the tubulin polymerization in a dose-dependent manner, and molecular docking analysis revealed a different binding mode with tubulin as compared with those known tubulin inhibitors.

Effects of long non-coding RNA-HOTAIR on the cell cycle and invasiveness of prostate cancer / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the expression of long non-coding RNA-HOTAIR in prostate cancer cells and its effects on the growth and metastasis of the cells.</p><p><b>METHODS</b>Using quantitative reverse-transcription PCR (qRT-PCR), we determined the relative expression of HOTAIR in the normal human prostate epithelial cell line RWPE-I and prostate cancer cell lines PC-3 and DU145. We detected the effects of HOTAIR on the cell cycle and invasiveness of prostate cancer cells by RNA interference, flow cytometry, and Transwell mitration assay.</p><p><b>RESULTS</b>The expressions of HOTAIR in the PC3 and DU145 cells were increased 3.2 and 5.7 times, respectively, as compared with that in the normal RWPE-1 cells. After si-HOTAIR interference, the prostate cancer cells were arrested in the G2 phase and downregulated in the G1 phase. The invasive ability of the prostate cancer cells was evidently inhibited, with the inhibition rates of 32% and 44% of the PC3 cells and 43% and 34% of the DU145 cells for si-HOTAIR1 and si-HOTAIR2, respectively.</p><p><b>CONCLUSION</b>IncRNA HOTAIR is highly expressed in prostate cancer, which is associated with the growth and invasiveness of prostate cancer cells. HOTAIR is potentially a novel marker for the diagnosis and prognosis of prostate cancer.</p>

Anti-cancer effects of novel doxorubicin prodrug PDOX in MCF-7 breast cancer cells / 华中科技大学学报（医学）（英德文版）

Ac-Phe-Lys-PABC-DOX (PDOX) is a smart doxorubicin (DOX) prodrug designed to decrease toxicities while maintaining the potent anticancer effects of DOX. This study was aimed at elucidating the effectiveness and toxicities of DOX and PDOX in patient-derived MCF-7 breast cancer cells in vitro. The MCF-7 cells were exposed to both PDOX and DOX, and cytotoxicities, cell cycle and P53/P21 signaling alterations were studied. Abundant cathepsin B was found in the MCF-7 cells, and treatment with PDOX and DOX triggered dose- and time-dependent cytotoxicity and resulted in a significant reduction in cell viability. The IC50 of PDOX and DOX was 3.91 and 0.94 μmol/L, respectively. Both PDOX and DOX caused an up-regulation of the P53/P21-related signal pathway, and PDOX significantly increased expression of P53 and caspase 3, and arrested the cell cycle at the G1/G2 phase. As compared with DOX, PDOX reduced toxicities, and it may have different action mechanisms on breast cancer cells.

The colchicine derivative CT20126 shows a novel microtubule-modulating activity with apoptosis

New colchicine analogs have been synthesized with the aim of developing stronger potential anticancer activities. Among the analogs, CT20126 has been previously reported to show immunosuppressive activities. Here, we report that CT20126 also shows potential anticancer effects via an unusual mechanism: the modulation of microtubule integrity and cell cycle arrest at the G2/M phase before apoptosis. When we treated COS-7 cells with CT20126 (5 muM), the normal thread-like microtubules were disrupted into tubulin dimers within 10 min and thereafter repolymerized into short, thick filaments. In contrast, cells treated with the same concentration of colchicine exhibited microtubule depolymerization after 20 min and never underwent repolymerization. Furthermore, optical density (OD) analysis (350 nm) with purified tubulin showed that CT20126 had a higher repolymerizing activity than that of Taxol, a potent microtubule-polymerizing agent. These results suggest that the effects of CT20126 on microtubule integrity differ from those of colchicine: the analog first destabilizes microtubules and then stabilizes the disrupted tubulins into short, thick polymers. Furthermore, CT20126 induced a greater level of apoptotic activity in Jurkat T cells than colchicine (assessed by G2/M arrest, caspase-3 activation and cell sorting). At 20 nM, CT20126 induced 47% apoptosis among Jurkat T cells, whereas colchicine induced only 33% apoptosis. Our results suggest that the colchicine analog CT20126 can potently induce apoptosis by disrupting microtubule integrity in a manner that differs from that of colchicine or Taxol.

Effect of RelB on HIV-1 Vpr-mediated transcription activation and cell G2/M arrest / 病毒学报

Vpr, an auxiliary protein of HIV-1(Human immunodeficiency virus type 1), exerts important functions to promote viral replication and AIDS progression. In this study, we performed a yeast two-hybrid screening assay using human cDNA library to further investigate the molecular mechanism of various functions of Vpr RelB, a key protein in NF-kappaB signaling pathway, was identified as a Vpr interaction protein by co-immunoprecipitation. Further investigations indicated that RelB not only promoted the Vpr-mediated activation of NF-kappaB reporter gene, but also enhanced the transactivation of HIV LTR. Moreover, the results showed that RelB promoted Vpr-induced cell cycle G2/M arrest. Collectively, these results indicated that RelB might interact with Vpr and regulate its transcriptional activation and cell cycle arrest.

Targeted deletion of mouse Rad1 leads to deficient cellular DNA damage responses

The Rad1 gene is evolutionarily conserved from yeast to human. The fission yeast Schizosaccharomyces pombe Rad1 ortholog promotes cell survival against DNA damage and is required for G(2)/M checkpoint activation. In this study, mouse embryonic stem (ES) cells with a targeted deletion of Mrad1, the mouse ortholog of this gene, were created to evaluate its function in mammalian cells. Mrad1 (-/-) ES cells were highly sensitive to ultraviolet-light (UV light), hydroxyurea (HU) and gamma rays, and were defective in G(2)/M as well as S/M checkpoints. These data indicate that Mrad1 is required for repairing DNA lesions induced by UV-light, HU and gamma rays, and for mediating G(2)/M and S/M checkpoint controls. We further demonstrated that Mrad1 plays an important role in homologous recombination repair (HRR) in ES cells, but a minor HRR role in differentiated mouse cells.

Effects of Chromosomal Polyploidy on Survival of Colon Cancer Cells / 대한소화기학회지

BACKGROUND/AIMS: Tetraploid cells are frequently observed in the inflamed mucosal epithelial cells of the patients with Barrett's esophagus or chronic ulcerative colitis. Polyploidy often occurs during cell fusion, abortive cell cycle, and endoreplication. Most tetraploid cells are engaged to apoptotic pathway, but some remaining stable tetraploid cells consequently cause aneuploidization and chromosomal instability. We investigated whether tetraploid cells could acquire survival advantage and hold a dominant position for natural selection. METHODS: We established tetraploid cell line (HCT116GH) from parental diploid colorectal cancer cell line (HCT116) via PEG-mediated cell fusion and compared its cell viability, cell cycle response and apoptotic fractions responded to H2O2 with diploid HCT116 and p53 suppressed HCT116/H6 cell lines. RESULTS: Using MTT assay, plating efficiency and clonogenicity, we evaluated the survival of each cell line. Tetraploid cell line HCT116GH demonstrated an 83 fold greater resistance to 100 microM H2O2 than the parental diploid HCT116, and 6 fold greater than even the p53 negative diploid HCT116/E6. Cellular sensitivity, G2/M arrests, and apoptotic proportion were observed less in response to H2O2 in HCT116GH compared with HCT116 and HCT116/E6. HCT116GH expressed lower level of p53 and p21 than diploid HCT116. CONCLUSIONS: Stable tetraploid cell lines showed enhanced viability in comparison to parental diploid cell lines. The enhanced viability observed in tetraploidization surpassed that from downregulation of p53. Frequent appearance of tetraploid cells in stressful condition can be caused by natural selection owing to their enhanced viability and may consequently contribute to cancer cell transformation.

Inhibition of cell proliferation by a resveratrol analog in human pancreatic and breast cancer cells

Resveratrol has been reported to possess cancer preventive properties. In this study, we analyzed anti-tumor activity of a newly synthesized resveratrol analog, cis-3,4',5-trimethoxy-3'-hydroxystilbene (hereafter called 11b) towards breast and pancreatic cancer cell lines. 11b treatments reduced the proliferation of human pancreatic and breast cancer cells, arrested cells in the G2/M phase, and increased the percentage of cells in the subG1/G0 fraction. The 11b treatments also increased the total levels of mitotic checkpoint proteins such as BubR1, Aurora B, Cyclin B, and phosphorylated histone H3. Mechanistically, 11b blocks microtubule polymerization in vitro and it disturbed microtubule networks in both pancreatic and breast cancer cell lines. Computational modeling of the 11b-tubulin interaction indicates that the dimethoxyphenyl group of 11b can bind to the colchicine binding site of tubulin. Our studies show that the 11b treatment effects occur at lower concentrations than similar effects associated with resveratrol treatments and that microtubules may be the primary target for the observed effects of 11b. These studies suggest that 11b should be further examined as a potentially potent clinical chemotherapeutic agent for treating pancreatic and breast cancer patients.

Discrimination of anticancer agent action loci at G(2) and M phases by flow cytometry and confocal microscopic imaging / 中国实验血液学杂志

This study was purposed to evaluate a method to discriminate the action loci of anticancer agents in G(2) and M phases of cell cycle. The meta-amsacrine (m-AMSA) and vinblastine (VBL), already known as G(2) and M phase arrest agent respectively, were used to induce the arrest of MOLT-4 cells at G(2) and M phases, the change of DNA content was detected by flow cytometry, the morphology of arrested cells was observed by confocal microscopy so as to find the arrest efficacy difference of 2 anticancer agents. As a result, the flow cytometric detection showed that the arrested MOLT-4 cells displayed the raise of peaks in G(2) and M phases, but flow cytometric detection alone can not discriminate the difference between them. The observation with confocal microscopy showed that the MOLT-4 cells arrested by m-AMSA displayed the morphologic features in G(2) phase, while the MOLT-4 cells arrested by VBL displayed the morphologic features in M phase. This observation with confocal microscopy is helpful to discriminate the difference between them. In conclusion, the combination of flow cytometry with confocal microscopy is one of the effective methods to discriminate the kind of G(2) or M phase arresting agent of anticancer drugs.

Inhibitive effect of 3-bromopyruvic acid on human breast cancer MCF-7 cells involves cell cycle arrest and apoptotic induction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Breast cancer is one of the most common malignancies in women and is highly resistant to chemotherapy. Due to its high tumour selectivity, 3-bromopyruvic acid (3-BrPA), a well-known inhibitor of energy metabolism has been proposed as a specific anticancer agent. The present study determined the effect of 3-BrPA on proliferation, cell cycle and apoptosis in the human breast cancer MCF-7 cell line and other antitumour mechanisms.</p><p><b>METHODS</b>MCF-7 cells were treated with various concentrations of 3-BrPA for 1 - 4 days, and cell growth was measured by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. Marked morphological changes in MCF-7 cells after treatment with 3-BrPA were observed using transmission electron microscopy. The distributions of the cell cycle and apoptosis were analyzed by flow cytometry. Immunohistochemistry was used to indicate the changes in the expression of Bcl-2, c-Myc, and mutant p53.</p><p><b>RESULTS</b>3-BrPA (25 microg/ml) significantly inhibited the proliferation of MCF-7 cells in a time-dependent manner. The MCF-7 cells exposed to 3-BrPA showed the typical morphological characteristics of apoptosis, including karyopycnosis, nuclear condensation and oversize cytoplasmic particles. In addition, flow cytometric assay also showed more apoptotic cells after 3-BrPA stimulation. The cells at the G0 and G1 phases were dramatically decreased while cells at the S and G2/M phases were increased in response to 3-BrPA treatment after 48 hours. Furthermore, 3-BrPA stimulation decreased the expressions of Bcl-2, c-Myc and mutant p53, which were strongly associated with the programmed cell death signal transduction pathway.</p><p><b>CONCLUSION</b>3-BrPA inhibits proliferation, induces S phase and G2/M phase arrest, and promotes apoptosis in MCF-7 cells, which processes might be mediated by the downregulation of the expressions of Bcl-2, c-Myc and mutant p53.</p>

Apoptosis induced by (di-isopropyloxyphoryl-Trp)2-Lys-OCH3 in K562 and HeLa cells.

According to the method used in our laboratory,our group synthesized (DIPP-Trp)2-Lys-OCH 3. It inhibited the proliferation of K562 and HeLa cells in a dose-and time-dependent manner with an IC 50 of 15.12 and 42.23 microM, respectively. (DIPP-Trp) 2-Lys-OCH3 induced a dose-dependent increase of the G2/M cell population in K562 cells, and S cell population in HeLa cells;the sub-G0 population increased dramatically in both cell lines as seen by PI staining experiments using a FACS Calibur Flow cytometer (BeckmanCoulter,USA). Phosphatidylserine could signi?cantly translocate to the surface of the membrane in (DIPP-Trp)2-Lys-OCH3-treated K562 and HeLa cells.The increase of an early apoptotic population was observed in a dose-dependent manner by both annexin-FITC and PI staining.It was concluded that (DIPP-Trp) 2-Lys-OCH3 not only induced cells to enter into apoptosis,but also affected the progress of the cell cycle.It may have arrested the K562 and HeLa cells in the G 2/M,S phases,respectively.The apoptotic pathway was pulsed at this point,resulting in the treated cells entering into programmed cell death.(DIPP- Trp)-Lys-OCH is a potential anticancer drug that intervenes in the signalling pathway.

Molecules of G(2)/M phase and the phosphorylation of survivin in the carcinogenesis of oral submucosal fibrosis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To determine the expression of Cyclin B1, p34(cdc2) and the phosphorylation of survivin (p-survivin) in oral squamous cell carcinoma and oral submucosa fibrosis (OSF), and to discuss their possible role in carcinogenesis of OSF.</p><p><b>METHODS</b>The expression of Cyclin B1, p34(cdc2) and p-survivin were analyzed by Western blotting assay in 10 cases of normal oral mucosa epithelium, 40 cases of OSF epithelium and 42 cases of oral squamous cell carcinoma (OSCC) originated from OSF, respectively. Immunoprecipitation was used to confirm the relationship between the p34(cdc2) and survivin.</p><p><b>RESULTS</b>The expression of Cyclin B1, p34(cdc2), p-p34(cdc2) and p-survivin in OSF group were significantly higher than those in normal group (P < 0.05). The expression of these molecules showed significant different (P < 0.05) between the OSF and OSCC originated from OSF, but there was no significant difference among the early stage, the moderately advanced stage and the advanced stage of OSF. Immunoprecipitation assay confirmed the combination of p34(cdc2) and survivin.</p><p><b>CONCLUSIONS</b>The important molecules in G(2)/M phase-Cyclin B1, p34(cdc2) and p-survivin may play a key role during the mitosis and proliferation of OSF, which will be helpful in early diagnosis and therapy of carcinogenesis of OSF.</p>

Mechanisms of G2/M cycle arrest induced by topo IIalpha and II beta inhibitors in H460 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the mechanisms of G(2)/M cycle arrest induced by topo IIalpha and IIbeta inhibitors in H460 cells.</p><p><b>METHODS</b>The inhibitory effects of XK469, adriamycin and etoposide on H460 cell growth were analyzed by MTT assay. The changes in cell cycle and expressions of cdc2, phos-cdc2 and 14-3-3sigma proteins induced by these 3 topo II inhibitors were detected by flow cytometry and Western blotting, respectively.</p><p><b>RESULTS</b>Both of the two types of topo II inhibitor resulted in dose-dependent G(2)/M phase arrest and growth inhibition of H460 cells, but XK469 failed to induce 14-3-3sigma protein expression as adriamycin and etoposide did.</p><p><b>CONCLUSION</b>Topo IIalpha and topo IIbeta inhibitors induce growth inhibition of H460 cells possibly through two different mechanisms, namely the 14-3-3sigma-dependent pathway and the 14-3-3sigma-independent pathway, but further functional inhibition test of 14-3-3sigma is needed to confirm this hypothesis.</p>

Induction of G2 /M phase arrest and apoptosis of MCF-7 cells by novel benzofuran lignan via suppressing cell cycle proteins / 药学学报

In the present study, a newly synthesized benzofuran lignan 4-formyl-2-(4-hydroxy-3methoxyphenyl)-5-(2-methoxycarbonyethyl)-7-methoxy-benzo [b] furan (ERJT-12) was tested for its antiproliferative activity on human tumor cells. The related mechanisms were also investigated. In vitro growth inhibitory effects of ERJT-12 on various cancer cell lines were determined by MTT assay. Cell cycle distribution and apoptosis were detected by flow cytometry. The integrity of DNA was assessed by agarose gel electrophoresis. Activation of Caspase-3/7 and Caspase-6 was measured by colorimetric assay. The expressions of cell cycle proteins cell divide cycle 25c (Cdc25c), cyclin dependent kinase 1 (CDK1), CyclinB1 and apoptosis-related proteins Bax and Bcl-2 were detected by Western blotting. MTT assay showed that ERJT-12 inhibited the proliferation of several cancer cell lines including multidrug resistant cells. MCF-7 cells were markedly arrested at gap2/mitosis (G2/M) phase after treatment with ERJT-12 and progressed into apoptosis. The increased activities of Caspase-3/7 and Caspase-6 in MCF-7 cells were observed. The expression of CyclinB1 was down-regulated. The activities of Cdc25c and CDK1 protein were suppressed and Bcl-2 protein was phosphorylated. ERJT-12 displays potent antiproliferative activity towards cancer cells through suppressing cell cycle proteins, arresting cell cycle at G2/M phase and inducing apoptosis. It might be a novel candidate for cancer therapy.

Studies of betuionic acid on cell cycle and related protein expressions on mice of bearing H22 tumor cells / 中国中药杂志

<p><b>OBJECTIVE</b>To study the betulonic acid on the cell cycle and related protein expressions on mice of bearing H22 tumor cells.</p><p><b>METHOD</b>Flow cytometray was used to observe the changes of betulonic acid on the cell cycle and P53 of H22 tumor cells. Immunohistochemistry was determined the espressions of PI3K and AKT.</p><p><b>RESULT</b>Increasing the doses of betulonic acid, the number of H22 cells in S phase and G2 phase was increasing gradually, it can speculate that when the betulonic acid act on cells, the cells were blocked in S and G2 phase and inhibited the protein expressions of PI3K and AKT.</p><p><b>CONCLUSION</b>Betulonic acid may be up-regulate the activity of P53 and inhibite the expressions of PI3K and AKT, so that it inhibited the survival pathway of tumor cells.</p>