Manuka honey enhanced sensitivity of HepG2, hepatocellular carcinoma cells, for Doxorubicin and induced apoptosis through inhibition of Wnt/ß-catenin and ERK1/2

BACKGROUND: Recently, there is increasing awareness focused on the identification of naturally occurring anticancer agents derived from natural products. Manuka honey (MH) has been recognized for its biological properties as antimicrobial, antioxidant, and anticancer properties. However, its antiproliferative mechanism in hepatocellular carcinoma is not investigated. The current study focused mainly on investigating the molecular mechanism and synergistic effect of anticancer properties of MH on Doxorubicin (DOX)-mediated apoptotic cell death, using two different p53 statuses (HepG2 and Hep3B) and one non-tumorigenic immortalized liver cell line. RESULTS: MH treatment showed a proliferative inhibitory effect on tested cells in a dose-dependent manner with IC50 concentration of (6.92 ± 0.005%) and (18.62 ± 0.07%) for HepG2 and Hep3B cells, respectively, and induced dramatic morphological changes of Hep-G2 cells, which considered as characteristics feature of apoptosis induction after 48 h of treatment. Our results showed that MH or combined treatments induced higher cytotoxicity in p53-wild type, HepG2, than in p53-null, Hep3B, cells. Cytotoxicity was not observed in normal liver cells. Furthermore, the synergistic effect of MH and Dox on apoptosis was evidenced by increased annexin-V-positive cells and Sub-G1 cells in both tested cell lines with a significant increase in the percentage of Hep-G2 cells at late apoptosis as confirmed by the flow cytometric analysis. Consistently, the proteolytic activities of caspase-3 and the degradation of poly (ADP-ribose) polymerase were also higher in the combined treatment which in turn accompanied by significant inhibitory effects of pERK1/2, mTOR, S6K, oncogenic ß-catenin, and cyclin D1 after 48 h. In contrast, the MH or combined treatment-induced apoptosis was accompanied by significantly upregulated expression of proapoptotic Bax protein and down-regulated expression of anti-apoptotic Bcl-2 protein after 48 h. CONCLUSIONS: Our data showed a synergistic inhibitory effect of MH on DOX-mediated apoptotic cell death in HCC cells. To our knowledge, the present study provides the first report on the anticancer activity of MH and its combined treatment with DOX on HCC cell lines, introducing MH as a promising natural and nontoxic anticancer compound.

The apoptosis induction on K562 cells by the CML bcr-abl gene antisense oligonucleotides / 中国癌症杂志

Background and purpose:As the development of the completion of the human genome project (HGP), the research focus is turning to the gene function research. At present, the domestic experimental research on the apoptosis of K562 cells induced by antisense olignonucleotides is rare. This study was aimed to investigate the effect of human chronic myelogenou leukemia (CML) bcr-abl fusion gene antisense oligonucletides on autophagy and apoptosis of CMLK562 cells in vitro. Methods:By liposome as the carrier, K562 cells were transfected with the bcr-abl gene antisense olignonucleotides. Hoechst staining method was used to observe the apoptosis inducing effect of different concentrations of oligonucleotides, the expressions of LC3-Ⅱ, autophagy-related protein, were determined by the Western blot method, the cell cycles were determined by lfow cytometry (FCM), and JEM-4000EX electron microscope technology was used to detect the apoptosis morphological changes. The apoptosis was detected by DNA agarose gel electrophoresis. Results:Hoechst staining results showed that the bcr-abl gene antisense oligonucletides signiifcantly promoted the apoptosis of K562 cells in a certain concentration dependent manner. Western blot showed that the expression level of LC3-Ⅱwas obviously higher in bcr-abl gene antisense oligonucletides transfected group than the control group, showing a promoting effect on cell autophagy. FCM test results showed that bcr-abl gene antisense oligonucleotides transfected K562 cells showed obvious cell cycle arrest, visible obvious apoptosis morphology under the electron microscope, and DNA Ladder showed obvious apoptosis fragments. Conclusion:The bcr-abl gene antisense olignonucleotides can signiifcantly induce the cell apoptosis of K562. This study provides a new method for CML therapy.

Cytotoxic activity and apoptosis induction of 8-hydroxyisocapnolactone-2´,3´-diol and its combination with Doxorubicin on MCF-7 and T47D cells.

The cytotoxic activity and apoptosis induction of 8-hydroxyisocapnolactone-2΄,3΄-diol (HICD) and its combination with doxorubicin (Doxo) on MCF-7 and T47D cells have been evaluated. The cytotoxic assay was performed using MTT method. The IC50 was used to express the cytotoxic potency, while the combination index (CI) was calculated to determine the effect of combination. The apoptotic assay was carried out using acrydine orange - ethidium bromide double staining method, while Bcl-2 and Bax expression were investigated by immunocytochemistry. The HICD exhibited cytotoxic activity on MCF-7 and T47D cells with the IC50 of 8 μg/ml (21.2 μM) and 4 μg/ml (10.6 μM), respectively. The combination of HICD with Doxo showed synergistic effect and increased apoptosis induction on both cell lines. The HICD did not affect Bcl-2 but increased Bax expression on MCF-7 cells, while on T47D cells it suppressed Bcl-2 expression but did not modulate Bax expression.

Synergistic anticancer effect of the extracts from Polyalthia evecta caused apoptosis in human hepatoma (HepG2) cells

Objective: To evaluate the anticancer activity of the extract fraction of Polyalthia evecta (P. evecta) (Pierre) Finet & Gagnep and the synergistic anticancer effect of the extracts from P. evecta by using the ATR/FT-IR spectroscopy. Methods: The 50% ethanol-water crude leaf extract of P. evecta (EW-L) was prepared and was further fractionated to isolate various fractions. The anticancer activity was investigated from cytotoxicity against HepG2 using a neutral red assay and apoptosis induction by evaluation of nuclei morphological changes after DAPI staining. Synergistic anticancer effects of the extracts from P. evecta were performed using the ATR/FT-IR spectroscopy. Results: The result showed that the EW-L showed higher cytotoxicity and apoptosis induction in HepG2 cells than its fractionated extracts. The hexane extract exhibited higher cytotoxicity and apoptosis induction than the water extracts, but less than the EW-L. The combined water and hexane extracts apparently increased cytotoxicity and apoptosis induction. The %apoptotic cells induced by the extract mixture were increased about 2-fold compared to the single hexane extract. Conclusions: The polar extract fraction is necessary for the anticancer activity of the non-polar extract fraction. The ATR/FT-IR spectra illustrates the physical interaction among the constituents in the extract mixture and reveals the presence of polyphenolic constituents in the EW-L, which might play a role for the synergistic anticancer effect.

Anticancer effect of the extracts from Polyalthia evecta against human hepatoma cell line (HepG2)

Objective: To investigate the anticancer activity of Polyalthia evecta (P. evecta) (Pierre) Finet& Gagnep against human hepatoma cell line (HepG2). Methods: The anticancer activity was based on (a) the cytotoxicity against human hepatoma cells (HepG2) assessed using a neutral red assay and (b) apoptosis induction determined by evaluation of nuclei morphological changes after DAPI staining. Preliminary phytochemical analysis of the crude extract was assessed by HPLC analysis. Results: The 50% ethanol-water crude leaf extract of P. evecta (EW-L) showed greater potential anticancer activity with high cytotoxicity [IC50 = (62.8 ± 7.3)μg/mL] and higher selectivity in HepG2 cells than normal Vero cells [selective index (SI) = 7.9]. The SI of EW-L was higher than the positive control, melphalan (SI = 1.6) and the apoptotic cells (46.4 ± 2.6) % induced by EW-L was higher than the melphalan (41.6 ± 2.1)% (P<0.05). The HPLC chromatogram of the EW-L revealed the presence of various kinds of polyphenolics and flavonoids in it. Conclusions:P. evecta is a potential plant with anticancer activity. The isolation of pure compounds and determination of the bioactivity of individual compounds will be further performed.