Inhibition of HL-60 cell growth via cell cycle arrest and apoptosis induction by a cycloartane-labdane heterodimer from Pseudolarix amabilis

Berberine regulates the Notch1/PTEN/PI3K/AKT/mTOR pathway and acts synergistically with 17-AAG and SAHA in SW480 colon cancer cells

CONTEXT

Berberine (BBR) is used to treat diarrhoea and gastroenteritis in the clinic. It was found to have anticolon cancer effects.

OBJECTIVE

To study the anticolon cancer mechanism of BBR by connectivity map (CMAP) analysis.

MATERIALS AND METHODS

CMAP based mechanistic prediction was conducted by comparing gene expression profiles of 10 μM BBR treated MCF-7 cells with that of clinical drugs such as helveticoside, ianatoside C, pyrvinium, gossypol and trifluoperazine. The treatment time was 12 h and two biological replications were performed. The DMSO-treated cells were selected as a control. The interaction between 100 μM BBR and target protein was measured by cellular thermal shift assay. The protein expression of 1-9 μM BBR treated SW480 cells were measured by WB assay. Apoptosis, cell cycle arrest, mitochondrial membrane potential (MMP) of 1-9 μM BBR treated SW480 cells were measured by flow cytometry and Hoechst 33342 staining methods.

RESULTS

CMAP analysis found 14 Hsp90, HDAC, PI3K or mTOR protein inhibitors have similar functions with BBR. The experiments showed that BBR inhibited SW480 cells proliferation with IC₅₀ of 3.436 μM, induced apoptosis, autophage, MMP depolarization and arrested G1 phase of cell cycle at 1.0 μM. BBR dose-dependently up-regulated PTEN, while inhibited Notch1, PI3K, Akt and mTOR proteins at 1.0-9.0 μM (p < 0.05). BBR also acted synergistically with Hsp90 and HDAC inhibitor (0.01 μM) in SW480 cells at 0.5 and 1.0 μM.

DISCUSSION AND CONCLUSIONS

The integrative gene expression-based chemical genomic method using CMAP analysis may be applicable for mechanistic studies of other multi-targets drugs.

Molecular mechanism underlying the apoptotic modulation by ethanol extract of Pseudolarix kaempferi in mucoepidermoid carcinoma of the salivary glands

Background

Pseudolarix kaempferi is a traditional Chinese natural product that possesses the potential cytotoxic effects against cancer. However, the precise molecular mechanism underlying its cytotoxic effects has not yet been completely elucidated. Here, we clarify the mechanism via which the ethanol extract of P. kaempferi (EEPK) leads to cytotoxicity mediated by apoptosis in mucoepidermoid carcinoma (MEC) originating from the salivary glands.

Methods

We investigated the mechanism underlying the anticancer efficacy of EEPK in human MEC in vitro by assessing mitochondrial dysfunction, mRNA levels, and morphological changes in apoptotic cell nuclei as well as by using a cytotoxicity assay, flow cytometric analysis, and western blotting.

Results

EEPK inhibited the growth of two human MEC cells and stimulated the induction of caspase-mediated apoptosis that was accompanied by mitochondrial membrane depolarization. Compared with the vehicle control groups, EEPK decreased myeloid cell leukemia-1 (Mcl-1) expression in both cells whereas it significantly decreased B cell lymphoma-2 (Bcl-2) expression in MC3 cells only. The EEPK-induced altered Mcl-1 expression was caused by translational inhibition and proteasomal degradation. Additionally, EEPK significantly increased p-Bcl-2 (Ser⁷⁰) expression regardless of its total forms by facilitating the activation of the c-Jun N-terminal kinase (JNK) signaling pathway, which exhibited cell context dependency. Nevertheless, JNK activation following EEPK treatment was, at least in part, required for the proapoptotic efficacy of EEPK in both cells.

Conclusions

This study revealed that EEPK-induced alterations of Mcl-1 inhibition and JNK/Bcl-2 phosphorylation cause apoptosis and provided basic preclinical data for future clinical trials regarding therapy for patients with MEC.

Graphic abstract

Identification of intracellular cadmium transformation in HepG2 and MCF-7 cells

It is of significance to elucidate or understand the intracellular transformation & migration behaviors of heavy metals in specific cells. Herein, we report the fast and efficient separation of cadmium-metallothioneins (Cd-MTs) and Cd²⁺in cell lysate by a short column capillary electrophoresis (SC-CE), followed by coupling with inductively coupled plasma mass spectrometry (ICP-MS) to facilitate the speciation of intracellular cadmium species. The incorporation of sodium dodecyl sulfate (SDS) in running buffer significantly reduces the peak width of Cd²⁺from 170 s to 26 s in the electrophoretogram, causing a 5.3-fold improvement on the sensitivity. Linear ranges of 0.5-50 mg L^-1,0.056-5.6 mg L^-1 and 0.1-10 mg L^-1 are achieved for MTs, Cd-MTs (Cd) and Cd²⁺, respectively, along with detection limits of 0.013 mg L^-1 for Cd-MTs (Cd) and 0.020 mg L^-1 for Cd²⁺. The transformation of cadmium in HepG2 and MCF-7 cells is evaluated after their incubation with Cd²⁺ reinforced culture medium. Intracellular free Cd²⁺ cation and Cd-MTs are identified, along with Cd²⁺ transformation to Cd-glutathione (GSH) adduct/complex, as further demonstrated by ESI-MS.

The antitumor effect of hinesol, extract from Atractylodes lancea (Thunb.) DC. by proliferation, inhibition, and apoptosis induction via MEK/ERK and NF-κB pathway in non-small cell lung cancer cell lines A549 and NCI-H1299

Lung cancer (especially, non-small cell lung cancer [NSCLC]) is one of the most malignant cancers in the world. Hinesol is the major component of the essential oil of Atractylodes lancea (Thunb.) DC and possesses the most promising anticancer function. However, the effects and molecular mechanism of hinesol on antiproliferation in NSCLC cells has not been well understood. In this study, we found that hinesol effectively inhibited the A549 and NCI-H1299 cells in a dose- and time-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay. In addition, hinesol induced cell cycle arrest at G0/G1 phase and apoptosis assessed by flow cytometry in A549 cells. Furthermore, Western blot analysis showed that hinesol decreased phosphorylation of mitogen-activated protein kinase, extracellular signal-regulated kinase, IκBα, and p65 inhibited the expressions of Bcl-2, cyclin D1 and upregulated the expression of Bax. Based on these results, hinesol might be a potential drug candidate of anti-NSCLC for therapy.

A novel polysaccharide derived from algae extract inhibits cancer progression via JNK, not via the p38 MAPK signaling pathway

Cancer has long been one of the most malignant diseases worldwide. Processes in cancer cells are often mediated by Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38 MAPK) and other signaling pathways. Traditional therapies are often problematic. Recently, a novel polysaccharide derived from algae extract was investigated due to the increasing interest in biological activities of compounds from marine organisms. The effect of this novel polysaccharide on human MKN45 gastric carcinoma cells was determined previously. The current aimed to determine whether the polysaccharide affects other types of cancer, and the deeper mechanisms involved in the process. Human MCF-7 breast cancer cells were used to investigate the novel polysaccharide for its role in the cell growth and migration, and determine the mechanisms affected. MTT assay, nuclear staining and fluorescence activated cell sorting analysis demonstrated that the novel polysaccharide reduced the viability of MCF-7 cells by inducing cell apoptosis and arresting the cells at G2/M phase. Results of western blot analysis demonstrated that phosphorylation of JNK and expression of p53, caspase-9 and caspase-3 were upregulated in the polysaccharide-treated MCF-7 cells. SP600125, an inhibitor of JNK, maintained MCF-7 cell viability, prevented cell apoptosis and cycle arrest, and downregulated the polysaccharide-induced protein phosphorylation/expression. However, a migration assay demonstrated that the novel polysaccharide did not change the migration of MCF-7 cells, as well as the expression of p38 MAPK, and matrix metalloproteinase-9 and -2. Taken together, the current study demonstrated that the novel polysaccharide suppressed cancer cell growth, induced cancer cell apoptosis and cell cycle arrest via JNK signaling, but had no effect on cancer cell migration and p38 MAPK signaling.