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Abstract Human mesenchymal stem cells (hMSCs) can be differentiated into osteoblasts and adipocytes. During these processes, super enhancers (SEs) play important roles. Here, we performed comprehensive characterization of the SEs changes associated with adipogenic and osteogenic differentiation of hMSCs, and revealed that SEs changed more dramatically compared with typical enhancers. We identified a set of lineage-selective SEs, whose target genes were enriched with cell type-specific functions. Functional experiments in lineage-selective SEs demonstrated their specific roles in directed differentiation of hMSCs. We also found that some key transcription factors regulated by lineage-selective SEs could form core regulatory circuitry (CRC) to regulate each other’s expression and control the hMSCs fate determination. In addition, we found that GWAS SNPs of osteoporosis and obesity were significantly enriched in osteoblasts-selective SEs or adipocytes-selective SEs, respectively. Taken together, our studies unveiled important roles of lineage-selective SEs in hMSCs differentiation into osteoblasts and adipocytes.

Background: Our previous study revealed that the combination of Saikosaponin-d (SSd) and radiation is more effective in the treatment of liver cancer than the application of either of these monotherapeutic methods. However, the molecular mechanisms of the radiosensitizing effect of SSd on liver cancer remained ill defined. Methods: Cells were treated with different interventions; afterward, cell viability, apoptosis, and cell survival of SMMC-7721 and HepG2 hepatoma cells were examined. Xenograft tumor models were established by subcutaneously injecting SMMC-7721 cells. The molecular mechanism was assessed by western blot. Results: SSd dose-dependently increased radiosensitivity of hepatoma cells under hypoxic condition. The growth inhibitory effect of the combined treatment was correlated with cell apoptosis. Further mechanistic analysis indicated that SSd induced the upregulation of p53 and Bax as well as the downregulation of Bcl-2 by attenuating HIF-1α expression under hypoxic condition. These effects were enhanced when the HIF-1α inhibitor PX-478 was introduced. In vivo data also presented a more significant suppression of tumor xenograft growth from the combined therapy than from either of the monotherapeutic methods. Conclusions: Our study provides evidence for a radiosensitizing effect of SSd on hepatoma cells under hypoxic conditions by inhibiting HIF-1α expression. Thus, SSd can be used as a potential sensitizer in hepatoma radiotherapy.

Metastasis is the major cause of cancer-related deaths. Targeting the process of metastasis has been proposed as a strategy to fight cancer. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used for treatment of many diseases, including cancer. This study aimed to determine the anti-metastatic effect of total flavonoids of S. barbata (TF-SB) using the human hepatocarcinoma MHCC97H cell line with high metastatic potential. Our results show that TF-SB could significantly inhibit the proliferation and invasion of MHCC97H cells in a dose-dependent manner. MMP-2 and MMP-9 expression were obviously decreased after TF-SB treatment at both the mRNA and protein level. TIMP-1 and TIMP-2 expression were simultaneously increased. The present study indicates that TF-SB could reduce the metastatic capability of MHCC97H cell, probably through decrease of the MMP expression, and simultaneous increase of the TIMP expression.

Rapamycin (Rapa), an inhibitor of mammalian target of Rapamycin (mTOR), is an immunosuppressive agent that has anti-proliferative effects on some tumors. This study aims to investigate the effects of Rapa suppressing proliferation of pancreatic carcinoma PC-2 cells in vitro and its molecular mechanism involved in antitumor activities. MTT assays showed that the inhibition of proliferation of PC-2 cells in vitro was in a time- and dose-dependent manner. By using transmission electron microscopy, apoptosis bodies and formation of abundant autophagic vacuoles were observed in PC-2 cells after Rapa treatment. Flow cytometry assays also showed Rapa had a positive effect on apoptosis. MDC staining showed that the fluorescent density was higher and the number of MDC-labeled particles in PC-2 cells was greater in the Rapa treatment group than in the control group. RT-PCR revealed that the expression levels of p53, Bax and Beclin 1 were up-regulated in a dose-dependent manner, indicating that Beclin 1 was involved in Rapa induced autophagy and Rapa induced apoptosis as well as p53 up-regulation in PC-2 cells. The results demonstrated that Rapa could effectively inhibit proliferation and induce apoptosis and autophagy in PC-2 cells.

In the present study, we investigated the in vitro and in vivo antitumor effects of crude extract of Scutellaria Barbate (CE-SB) on mouse hepatoma H22 cells. The MTT assay was used to determine the growth inhibition of H22 cells in vitro. The in vivo therapeutic effects of CE-SB were determined using H22 tumor bearing mice. Besides, the body weight, tumor weight, thymus index and spleen index of H22 bearing mice were also measured. The tumor inhibitory rate (IR) was calculated according to the mean weight of tumor (MWT). The phagocytotic function of macrophages was examined by observing peritoneal macrophages phagocytize chicken RBC. The results showed that CE-SB could inhibit the growth of hepatoma H22 Cells in vitro and in vivo. Furthermore, CE-SB could improve immune function of H22 tumor bearing mice. Together these results indicate that CE-SB has antitumor activity and seems to be safe and effective for the use of anti-tumor therapy.

Purpose: To investigate the effect of 2-[(4-hydroxy-phenylamino)-methylene]-5,5-dimethyl-cyclohex (HPDH) on mammary carcinogenesis induced by 7,12-dimethylbenz(a)anthracene in female Sprague Dawley rats. Methods: Among three groups of rats (50 each) used in the study, the control group was fed standard diet alone, ibuprofen group received standard diet containing 1200 mg/kg ibuprofen while HPDH group was administered standard diet containing 1200 mg/kg HPDH. The treatment was for 10 days for all the groups. All the animals received 20 mg of DMBA intragastrically by gavage. Clinical parameters for the rats were recorded weekly. Micrometer caliper was used to measure the diameter of all the tumors at the end of the experiment and tumor volume calculated. Histological evaluation was performed using hematoxylin and eosin (H&E) staining. High performance liquid chromatography (HPLC) was used to determine the level of HPDH and ibuprofen in the serum of the animals. Results: The data revealed a significant decrease in the number of rats with mammary tumor, number of tumors/rat and tumor volume by 54, 72 and 75 %, respectively, in HPDH group compared to control group. The ibuprofen-treated rats also showed significant decrease in the number of rats with tumor, number of tumors/rat and tumor volume by 43, 55, and 59 %, respectively. Treatment of rats with HPDH increased the latency period of tumor induction significantly (p < 0.005). Median detection period (50 % of tumors) was 92, 83 and 56 days, respectively, in HPDH, ibuprofen and control groups, respectively, after DMBA induction. Conclusion: These results demonstrate that HPDH possesses strong chemopreventive activity against mammary carcinogenesis. [ABSTRACT FROM AUTHOR]

Background Cyclooxygenase (COX) is a rate-limiting enzyme in prostaglandins synthesis which exists in two isoforms, COX-1 and COX-2. Over-expression of COX-2 was considered to increase the proliferation and enhance the invasiveness of breast cancer cells. It was suggested that genetic variations in COX-2 could influence its expression. Herein, the present study was aimed to investigate the associations between two mostly studied functional polymorphisms (-765 G > C and 8473 C > T) in COX-2 and breast cancer risk in Chinese Han women. Methods In the hospital-based case-control study, 465 breast cancer patients and 799 cancer-free controls were genotyped for the COX-2 -765 G > C and 8473 C > T polymorphisms using TaqMan assay. We estimated odds ratios (ORs) and 95% confidence intervals (95% CIs) using the logistic regression. Results Compared with the wild genotype of -765 G > C, we found a statistically significant increased risk of breast cancer associated with the variant genotypes [GC/CC vs. GG: OR = 1.56, 95% CI = 1.11-2.21]. In the stratified analysis, the increased risk was more predominant among the subgroups of younger subjects (OR = 1.61, 95% CI = 1.00-2.61). Furthermore, the variant genotypes were associated with large tumor size (OR = 3.01, 95% CI = 1.47-6.12). No significant association was observed for the 8473 C > T polymorphism. Conclusions Our results suggest that the functional -765 G > C polymorphism in the promoter of COX-2 may influence the susceptibility and progression of breast cancer in the Chinese Han population. [ABSTRACT FROM AUTHOR]

Several single nucleotide polymorphisms have been identified in cyclooxygenase-2 (COX-2) genes (e.g., -765 G>C (rs20417), -1195G>A (rs689466), and 8473 C>T (rs5275)). The association of these SNPs with the risk of different cancer types is still controversial. This study aims to evaluate the correlation between these SNPs and breast cancer risk in different ethnic groups. We have searched PubMed, Web of Knowledge, and Embase for relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of the associations. A total of 13 studies (15,330 cases and 19,260 controls) were eligible for meta-analysis. This meta-analysis showed that COX-2 rs20417 polymorphism was correlated with an increased risk of breast cancer in Caucasians, while rs689466 was associated with a decreased risk of breast cancer in Caucasians. The rs5275 polymorphism had no association with breast cancer risk. [ABSTRACT FROM AUTHOR]

Runt-related transcription factor 3 (RUNX3) is a tumor suppressor gene, its inactivation due to hypermethylation related to carcinogenesis. The aim of this study was to investigate the effects of 5-aza-2'-deoxycytidine (5-Aza-CdR) on cell proliferation and apoptosis by demethylation of the promoter region and restoring the expression of RUNX3 in the breast cancer MCF-7 cell line. MCF-7 cells were cultured with different concentrations (0.4-102.4 μmol/L) of 5-Aza-CdR in vitro. MTT assay was used to determine the proliferation of MCF-7 cells. Flow cytometry and Hoechst staining were used for analyzing cell apoptosis. The methylation status and expression of RUNX3 in mRNA and protein levels were measured by methylation-specific polymerase chain reaction (PCR [MSP]), reverse transcription (RT)-PCR, and Western blot. It was shown that the RUNX3 gene downregulated and hypermethylated in MCF-7 cells. 5-Aza-CdR induced demethylation, upregulated the expression of RUNX3 on both mRNA and protein levels in cancer cells, and induced growth suppression and apoptosis in vitro in a dose- and time-dependent manner. The results demonstrate that RUNX3 downregulation in breast cancer is frequently due to hypermethylation, and that 5-Aza-CdR can inhibit cell proliferation and induce apoptosis by eliminating the methylation status of RUNX3 promoter and restoring its expression. [ABSTRACT FROM AUTHOR]

Background: ß-elemene, a natural sesquiterpene extracted from the essential oils of Curcuma aromatica Salisb, has been shown to be effective against a wide range of tumors. In this study, the antitumor effect of ß-elemene on a human hepatoma cell line, HepG2, and the mechanism involved have been investigated. Methods: MTT assay was used to determine the growth inhibition of hepatoma HepG2 cells in vitro. Apoptosis of HepG2 cells were demonstrated by fluorescence microscope with Hoechst 33258 staining and flow cytometry with Annexin V-FITC/PI double staining. Flow cytometry was performed to analyze the cell cycle distribution of HepG2 cells. The mRNA and protein expression of Fas and FasL were measured by RT-PCR and Western blot analysis. Results: MTT results showed that ß-elemene could inhibit the proliferation of HepG2 cells in a time- and dosedependent manner. Our results showed ß-elemene had positive effect on apoptosis through fluorescence microscope and flow cytometry assay. Furthermore, ß-elemene could induce the cell cycle arrest of the HepG2 cells in the G2/M phase. Fas and FasL expression were obviously increased after ß-elemene treatment in both mRNA and protein level. Conclusion: The present study indicates that ß-elemene can effectively inhibit proliferation and induce apoptosis in hepatoma HepG2 cells, and the apoptosis induction is related with up-regulating of Fas/FasL expression. [ABSTRACT FROM AUTHOR]

Rapamycin (Rapa), an inhibitor of mammalian target of Rapamycin (mTOR), is an immunosuppressive agent that has anti-proliferative effects on some tumors. This study aims to investigate the effects of Rapa suppressing proliferation of pancreatic carcinoma PC-2 cells in vitro and its molecular mechanism involved in antitumor activities. MTT assays showed that the inhibition of proliferation of PC-2 cells in vitro was in a time- and dose-dependent manner. By using transmission electron microscopy, apoptosis bodies and formation of abundant autophagic vacuoles were observed in PC-2 cells after Rapa treatment. Flow cytometry assays also showed Rapa had a positive effect on apoptosis. MDC staining showed that the fluorescent density was higher and the number of MDC-labeled particles in PC-2 cells was greater in the Rapa treatment group than in the control group. RT-PCR revealed that the expression levels of p53, Bax and Beclin 1 were up-regulated in a dose-dependent manner, indicating that Beclin 1 was involved in Rapa induced autophagy and Rapa induced apoptosis as well as p53 up-regulation in PC-2 cells. The results demonstrated that Rapa could effectively inhibit proliferation and induce apoptosis and autophagy in PC-2 cells. [ABSTRACT FROM AUTHOR]

Background: Angiogenesis is closely related to the growth, invasion and metastasis of tumors, also considered as the key target of anticancer therapy. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is being used to treat various diseases, including cancer. However, the antitumor molecular mechanism of S. barbata was still unclear. This study aimed to investigate the inhibitory effects of the total flavones in S. barbata (TF-SB) on angiogenesis. Methods: Human umbilical vein endothelial cells (HUVECs) were treated with various concentrations of TF-SB. Cell viability was examined using the MTT assay. The scratch assay was used to detect the migration of HUVECs after treatment with TF-SB. The ability of HUVECs to form network structures in vitro was demonstrated using the tube formation assay. The chick embryo chorioallantoic membrane assay was performed to detect the in vivo antiangiogenic effect. The expression of VEGF was measured by the enzyme-linked immunosorbent. Results: Results showed that TF-SB inhibited the proliferation and migration of HUVECs in a dose- dependent manner. Simultaneously, TF-SB significantly suppressed HUVEC angiogenesis in vitro and in vivo. Furthermore, VEGF was downregulated in both HUVECs and MHCC97-H cells after TF-SB treatment. Conclusion: TF-SB could suppress the process of angiogenesis in vitro and in vivo. TF-SB potentially suppresses angiogenesis in HUVECs by regulating VEGF. These findings suggested that TF-SB may serve as a potent antiangiogenic agent. [ABSTRACT FROM AUTHOR]

Background: Radiation-induced skin injury is a common complication of radiotherapy. The RHIZOMA COPTIDIS and COPTIS CHINENSIS aqueous extract (RCE) can ameliorate radiation-induced skin injury in our clinical observation. But, the protective mechanism of RHIZOMA COPTIDIS and COPTIS CHINENSIS in radiation-induced skin injury remains unclear. Methods: In this experiment, we developed a radiation-induced skin injury rat model to study the mechanism. The animals were randomly divided into control group, treatment group, radiation group, and treatment and radiation group. 5 rats in each group were separately executed on 2 d and 49 d post-radiation. The semi-quantitative skin injury score was used to measure skin reactions by unblinded observers, and hematoxylin and eosin staining was used to evaluate the damage areas by irradiation. The MDA content, SOD activity of skin and serum were measured to detect the oxidative stress. Results: Acute skin reactions were caused by a single dose of 45 Gy of ?-ray irradiation, and the skin injury could be found in all rats receiving irradiation based on the observation of HE staining of skin at different time-points, while RCE could significantly ameliorate those changes. The MDA content in serum and skin of control rats was 4.13 ± 0.12 mmol/ ml and 4.95 ± 0.35 mmol/mgprot on 2 d post-radiation. The rats receiving radiation showed an increased content of MDA (5.54 ± 0.21 mmol/ml and 7.10 ± 0.32 mmol/mgprot), while it was 4.57 ± 0.21 mmol/ml and 5.95 ± 0.24 mmol/ mgprot after treated with RCE (p < 0.05). Similar changes of the MDA content could be seen on 49 d post-radiation. However, the SOD activity of rats receiving radiation decreased compared with control group on both time-points, which was inhibited by RCE (p < 0.05). Meanwhile, no valuable changes could be found between control group and treatment group on 2 d and 49 d. Conclusions: Our study provides evidences for the radioprotective role of RCE against radiation-induced skin damage in rats by modulating oxidative stress in skin, which may be a useful therapy for radiation-induced skin injury. [ABSTRACT FROM AUTHOR]

Metastasis is the major cause of cancer-related deaths. Targeting the process of metastasis has been proposed as a strategy to fight cancer. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used for treatment of many diseases, including cancer. This study aimed to determine the anti-metastatic effect of total flavonoids of S. barbata (TF-SB) using the human hepatocarcinoma MHCC97H cell line with high metastatic potential. Our results show that TF-SB could significantly inhibit the proliferation and invasion of MHCC97H cells in a dose-dependent manner. MMP-2 and MMP-9 expression were obviously decreased after TF-SB treatment at both the mRNA and protein level. TIMP-1 and TIMP-2 expression were simultaneously increased. The present study indicates that TF-SB could reduce the metastatic capability of MHCC97H cell, probably through decrease of the MMP expression, and simultaneous increase of the TIMP expression. [ABSTRACT FROM AUTHOR]

Background: Cyclooxygenase-2(COX-2) promotes carcinogenesis, tumor proliferation, angiogenesis, prevention of apoptosis, and immunosuppression. Meanwhile, COX-2 over-expression has been associated with tumor behavior and prognosis in several cancers. This study investigated the antitumor effects of the selective COX-2 inhibitor, Celecoxib, on breast cancer in vitro and in vivo. Methods: Human breast cancer MCF-7 and MDA-MB-231 cells were cultured with different concentration (10, 20, 40 µmol/L) of celecoxib after 0-96 hours in vitro. MTT assay was used to determine the growth inhibition of breast cancer cells in vitro. The expression of COX-2 on mRNA was measured by real-time quantitive PCR analysis. Flow cytometry was performed to analyze the cell cycle of MCF-7 cells. Levels of PGE2 were measured by ELISA method. The in vivo therapeutic effects of celecoxib were determined using rat breast cancer chemically induced by 7,12-dimethylben anthracene (DMBA). Results: The inhibition of proliferation of both MCF-7 and MDA-MB-231 cells in vitro by celecoxib was observerd in time and dose dependent manner. Celecoxib effectively down-regulated the expression of COX-2. The cell cycle was arrested at G0/G1, and rate of cells in S phase was obviously decreased. Levels of PGE2 were inhibited by Celecoxib. The tumor incidence rate of the celecoxib group was lower than that of the control group. In addition, the tumor latency period of the celecoxib group was longer than that of the control group. Conclusions: Celecoxib inhibited the proliferation of breast cancer cell lines in vitro, and prevented the occurrence of rat breast cancer chemically induced by DMBA. Therefore, celecoxib exhibits an antitumor activity and seems to be effective in anti-tumor therapy. [ABSTRACT FROM AUTHOR]

Background: Diffusion-weighted (DW) imaging has shown potential to differentiate between malignant and benign breast lesions. However, different b values have been used with varied sensitivity and specificity. This study aims to prospectively evaluate the influence of b value on the detection and assessment of breast lesions. Methods: Institutional review board approval and informed patient consent were obtained. Between February 2010 and September 2010, sixty women suspected of having breast cancer by clinical examination and mammography underwent bilateral breast MRI and DW imaging (with maximum b values of 600, 800, and 1000 s/mm2). Conspicuity grades of lesions at different b values on DW images were performed. Signal intensity and apparent diffusion coefficient (ADC) values were recorded and compared among different b values by the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and receiver operating characteristic (ROC) curve. Results: Fifty-seven lesions from 52 recruited patients including 39/57 (68%) malignant and 18/57 (32%) benign were confirmed with pathology. DCE MRI accurately detected 53 lesions with the sensitivity of 93.0% and specificity of 66.7%, and DW imaging accurately detected 51 lesions with the sensitivity of 89.5% and specificity of 100%. There were no significant differences in conspicuity grades compared among the three b values (P = 0.072), although the SNR and CNR of breast lesions decreased significantly with higher b values. Mean ADCs of malignant lesions (b = 600 s/mm2, 1.07 ± 0.26 × 10-3 mm2/s; b = 800 s/mm2, 0.96 ± 0.22 × 10-3 mm2/s; b = 1000 s/mm2, 0.92 ± 0.26 × 10-3 mm2/s) were significantly lower than those of benign lesions (b = 600 s/mm2, 1.55 ± 0.40 × 10-3 mm2/s; b = 800 s/mm2, 1.43 ± 0.38 × 10-3 mm2/s; b = 1000 s/mm2, 1.49 ± 0.38 × 10-3 mm2/s) with all P values <0.001, but there were no significant differences among the three b values (P = 0.303 and 0.840 for malignant and benign lesions, respectively). According to the area under the ROC curves, which were derived from ADC and differentiate malignant from benign lesions, no significant differences were found among the three b values (P = 0.743). Conclusions: DW imaging is a potential adjunct to conventional MRI in the differentiation between malignant and benign breast lesions. Varying the maximum b value from 600 to 1000 s/mm2 does not influence the conspicuity of breast lesions on DW imaging at 1.5 [ABSTRACT FROM AUTHOR]

In the present study, we investigated the in vitro and in vivo antitumor effects of crude extract of Scutellaria barbate (CE-SB) on mouse hepatoma H22 cells. The MTT assay was used to determine the growth inhibition of H22 cells in vitro. The in vivo therapeutic effects of CE-SB were determined using H22 tumor bearing mice. Besides, the body weight, tumor weight, thymus index and spleen index of H22 bearing mice were also measured. The tumor inhibitory rate (IR) was calculated according to the mean weight of tumor (MWT). The phagocytotic function of macrophages was examined by observing peritoneal macrophages phagocytize chicken RBC. The results showed that CE-SB could inhibit the growth of hepatoma H22 Cells in vitro and in vivo. Furthermore, CE-SB could improve immune function of H22 tumor bearing mice. Together these results indicate that CE-SB has antitumor activity and seems to be safe and effective for the use of anti-tumor therapy. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the relationship between apurinic endonuclease 1 (APE1) Asp148Glu polymorphism and the susceptibility to gastrointestinal (GI) cancers., Methods: We searched PubMed, ISI Web of Knowledge, and Chinese National Knowledge Infrastructure (CNKI) databases updated on July 15, 2014 for relevant studies. Only case-control studies comparing APE1 Asp148Glu polymorphism and GI cancer risk were included. We excluded studies reporting only standardized incidence ratios without control groups and those without detailed genotyping data. Meta-analysis was performed on 17 studies involving 4856 cancer patients and 6136 cancer-free controls. Review Manager version 5.1 was used to perform the meta-analysis. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated under the allele contrast, homozygous, heterozygous, dominant and recessive genetic models. We also conducted subgroup analyses stratified by ethnicity and cancer type. Publication bias was evaluated using Begg's test., Results: The meta-analysis showed a significant association between APE1 Asp148Glu polymorphism and GI cancer risk in three genetic models in the overall population (G vs T: OR = 1.18; 95%CI: 1.05-1.32; TG vs TT: OR = 1.28; 95%CI: 1.08-1.52; TG + GG vs TT: OR = 1.32; 95%CI: 1.10-1.57). Stratified analysis by ethnicity revealed a statistically increased GI cancer risk in Asians (G vs T: OR = 1.27; 95%CI: 1.07-1.51; GG vs TT: OR = 1.58; 95%CI: 1.05-2.38; TG vs TT: OR = 1.30; 95%CI, 1.01- 1.67; and TG + GG vs TT: OR = 1.38; 95%CI: 1.07-1.78), but not in Caucasians. Further subgroup analysis by cancer type indicated that APE1 Asp148Glu polymorphism may contribute to gastric cancer risk. However, Asp148Glu has no significant association with colorectal or esophageal cancer risk in any genetic model., Conclusion: This meta-analysis suggests that the APE1 Asp148Glu polymorphism G allele is associated with an increased GI cancer risk, especially in gastric cancer.