Curcumol Inhibits Growth and Induces Apoptosis of Colorectal Cancer LoVo Cell Line via IGF-1R and p38 MAPK Pathway

Curcumol Exerts Anticancer Effect in Cholangiocarcinoma Cells via Down-Regulating CDKL3

Curcumol is the major component extracted from root of Rhizoma Curcumae. Recent studies have shown that curcumol exerts therapeutic effects against multiple conditions, particularly cancers. However, the therapeutic role and mechanism of curcumol against cholangiocarcinoma cells are still unclear. In our current research, we tested the effect of curcumol in cholangiocarcinoma cells, and using two-dimensional electrophoresis, proteomics and bioinformatics, we identified cyclin-dependent kinase like 3 (CDKL3) as a potential target for curcumol. We have demonstrated that curcumol can evidently suppress growth and migration of cholangiocarcinoma cells. Furthermore, curcumol could significantly block the cell cycle progression of the cholangiocarcinoma cells. These effects could be largely attributed to the inhibition of CDKL3 by curcumol. Further studies have recapitulated the oncogenic role of CDKL3 in that knockdown of CDKL3 by lentiviral mediated transfection of shRNA against CDKL3 also led to a significant inhibition on cell proliferation, migration, invasion, and cell cycle progression. Given the high level of CDKL3 expression in human cholangiocarcinoma tissues and cell lines, we speculated that CDKL3 may constitute a potential biological target for curcumol in cholangiocarcinoma.

Curcumol Controls Choriocarcinoma Stem-Like Cells Self-Renewal via Repression of DNA Methyltransferase (DNMT)- and Histone Deacetylase (HDAC)-Mediated Epigenetic Regulation

BACKGROUND Cancer stem cells (CSCs), in choriocarcinoma and other carcinomas, possess the ability of self-renewal and multilineage differentiation potential. We previous isolated choriocarcinoma cancer stem-like cells (CSLCs), which hold the stemness characteristics of CSCs. Epigenetic modifications have emerged as drivers in tumorigenesis, but the mechanisms of CSCs are largely unknown, and new drug therapies are needed to break the persistence of CSCs. MATERIAL AND METHODS Quantitative real-time PCR (qRT-PCR) and Western blot analysis were performed to detect the expression of DNMTs, HDACs, and stemness-genes. DNMTs and HDACs silencing and overexpressing lentivirus were transfected into JEG-3 cells to investigate the epigenetic functions in CSLCs. In vivo expression of curcumol effects of CSLCs on DNMTs and HDACs were analyzed by immunohistochemistry. RESULTS Expression of DNMT1, DNMT3b, HDAC1, and HDAC3 were increased in choriocarcinoma CSLCs. Consistent with the inhibitory effect of 5-AzaC and TSA on CSLCs, DNMT/HDAC knockdown displayed significant repression of self-renewal in CSLCs. Curcumol inhibited the stemness ability of CSLCs in vitro and in vivo, and the inhibitory effect we observed was mediated in part through repressing activity of DNMTs and HDACs. Importantly, curcumol showed a better effect than DNMT and HDAC inhibitors combined in eliminating CSLCs. CONCLUSIONS These findings indicate that DNMT- and HDAC-mediated epigenetic regulation plays an important role in the biology of choriocarcinoma CSLCs, and curcumol has the potential to be a new drug to fight CSLCs, warranting further investigation of epigenetic-based therapies.

Curcumol induces cell cycle arrest in colon cancer cells via reactive oxygen species and Akt/ GSK3β/cyclin D1 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Curcuma kwangsiensis S. G. Lee & C. F. Liang (Guangxi ezhu, in Chinese) belongs to the Zingiberaceae family, has been used as a traditionally Chinese medicine nearly 2000 year. Curcumol is one of the guaiane-type sesquiterpenoid hemiketal isolated from medicine plant Curcuma kwangsiensis S. G. Lee & C. F. Liang, which has been reported possesses anti-cancer effects. Our previous study found that the most contribution to inhibit nasopharyngeal carcinoma cell growth was curcumol.

AIM OF THE STUDY

To assess the effect of curcumol on cell cycle arrest against human colon cancer cells (CRC) cells (LoVo and SW480) and explore its mechanism in vitro and in vivo.

MATERIALS AND METHODS

Curcumol was dissolved in absolute ethyl alcohol. The concentration of absolute ethyl alcohol in the control group or in experimental samples was always 1/500 (v/v) of the final medium volume. LoVo and SW480 cells were treated with different concentrations of curcumol (0, 53, 106, 212 and 424μM). And then the cell cycle of each group was examined by flow cytometry. The protein levels of PI3K, p-Akt, cyclin D1, cyclin E, CDK2, CDK4 and GSK3β were determined by Western blot. The mRNA expression of PI3K, Akt, cyclin D1, CDK4, P27, p21, and P16 in the treated cells were analyzed by real-time RT-PCR. In addition, the antitumor activity of curcumol was evaluated in nude mice bearing orthotopic tumor implants.

RESULTS

Curcumol induced cell cycle arrest in G1/S phase. RT-qPCR and Western blot data showed that curcumol enhanced the expression of GSK3β, P27, p21 and P16, and decreased the levels of PI3K, phosphorylated Akt (p-Akt), cyclin D1, CDK4, cyclin E and CDK2. Furthermore, curcumol induced reactive oxygen species (ROS) generation in LoVo cells, and ROS scavenger N-acetylcysteine (NAC) significantly reversed curcumol-induced cell growth inhibition. Besides, curcumol also prevented the growth of human colon cancer cells xenografts in nude mouse, accompanied by the reduction of PI3K, Akt, cyclin D1, CDK4, cycln E and significant increase of GSK3β.

CONCLUSIONS

Curcumol caused cell cycle arrest at the G0/G1 phase by ROS production and Akt/ GSK3β/cyclin D1 pathways inactivation, indicating the potential of curcumol in the prevention of colon cancer carcinogenesis.

Application of a rhodium-catalyzed cyclization cycloaddition cascade strategy to the total synthesis of (−)-curcumol

The first de novo total synthesis of (−)-curcumol was accomplished using a rhodium-catalyzed cyclization–cycloaddition cascade reaction as the key step.

Inhibition of autophagy attenuated curcumol-induced apoptosis in MG-63 human osteosarcoma cells via Janus kinase signaling pathway

The present study aimed to investigate whether autophagy was triggered by curcumol and to explore the association between autophagy and apoptosis of MG-63 cells and the underlying mechanism. MG-63 cells were cultured in vitro. An MTT assay was performed to evaluate the proliferation inhibition of the MG-63 osteosarcoma cell line by curcumol. Fluorescein isothiocyanate-Annexin V/propidium iodide staining flow cytometry was performed to analyze the apoptotic rate of cells. The morphological alterations of cell nuclei were evaluated by Hoechst 33258 viable cell staining. The effects of autophagy in cells was investigated by green fluorescent protein (GFP)-light chain 3 (LC3) transfection and using a fluorescence microscope. The expression levels of LC3II, LC3I and cleaved caspase-3 and Janus kinase (JNK) signaling pathway activation were determined by western blot analysis. Cell proliferation was inhibited by curcumol in a dose- and time-dependent manner. Curcumol induced apoptosis by the caspase-dependent signaling pathway in MG-63 cells. The present study demonstrated that curcumol could induce autophagy of MG-63 cells, which was evaluated by transmission electron microscopy. Compared with the curcumol treatment alone group, the GFP-LC3-transfected green fluorescence plasmids and the LC3II/LC3I levels in cells of the curcumol and chloroquine (CQ) treatment group were upregulated, and the apoptotic ratio was downregulated following pretreatment with autophagy inhibitor CQ for 1 h. Furthermore, curcumol treatment induced phosphorylation of the JNK signaling pathway. Of note, pretreatment with the JNK inhibitor, SP600125, decreased the rates of autophagy and apoptosis, suggesting a crucial role served by the JNK signaling pathway in the activation of autophagy by curcumol. Taken together, the results of the present study suggested that activation of the JNK signaling pathway was involved in curcumol-induced autophagy. Curcumol is a novel drug for chemotherapeutic combination therapy. Curcumol demonstrated potential antitumor activities in MG-63 cells and may be used as a novel effective reagent in the treatment of osteosarcoma.

ANP32A modulates cell growth by regulating p38 and Akt activity in colorectal cancer

Acidic leucine-rich nuclear phosphoprotein-32A (ANP32A) possesses multiple biochemical activities, has been found to be decreased or absent in malignant tumors. However, new findings have shown that it is expressed in greater amounts in advanced cancers than in early-stage tumors. The role and clinical significance of ANP32A in colorectal cancer (CRC) is still unknown. In the present study, the expression of ANP32A was assessed in 68 CRC patients by IHC, and then the correlation of its expression with clinicopathological factors was investigated using the Allred, Klein and immune response scoring system analysis. Western blot and real-time PCR analyses were used to assess ANP32A expression and the activity of Akt and p38 in cancer and normal tissues. These data indicated a significant association between ANP32A expression and the activity of Akt and p38, besides the tumor differentiation status in CRC patients. IHC and western blotting data revealed that ANP32A was overexpressed in CRC patients, and ANP32A levels were higher in poorly differentiated tumors. Protein and mRNA analysis revealed that with a high expression of ANP32A, the activation of Akt was enhanced, while the p-38 phosphorylation level was decreased in CRC tissues. MTT assay and functional studies revealed that knockdown of ANP32A inhibited cell growth and induced p38 phosphorylation and Akt dephosphorylation. The present study indicated that ANP32A promoted CRC proliferation by inhibition of p38 and activation of Akt signaling pathways and suggested that ANP32A may play a potential role in CRC diagnosis and therapy.

Proteomic Identification of eEF1A1 as a Molecular Target of Curcumol for Suppressing Metastasis of MDA-MB-231 Cells

Curcumol, a major volatile component in Rhizoma Curcumae, exhibits a potent antimetastatic effect on breast cancer cells. However, its molecular mechanism remains poorly understood. In this study, we employed two-dimensional gel electrophoresis-based proteomics to investigate the cellular targets of curcumol in MDA-MB-231 cells and identified 10 differentially expressed proteins. Moreover, Gene Ontology analysis revealed that these proteins are mainly involved in nine types of cellular components, seven different biological processes, and nine kinds of molecular functions, and 35 pathways (p < 0.05) were enriched by KEGG pathway analysis. Specially, eEF1A1, a well-characterized actin binding protein, draws our attention. Curcumol decreased eEF1A1 expression at both mRNA and protein levels. EEF1A1 expression was shown to be correlated with the invasiveness of cancer cells. Importantly, overexpression of eEF1A1 significantly reversed the inhibition of curcumol regarding the invasion and adhesion of MDA-MB-231 cells (p < 0.05). Together, our data suggest that eEF1A1 may be a potential molecular target underlying the antimetastatic effect of curcumol.

A Case of Recurrent Hepatocellular Carcinoma Acquiring Complete Remission of Target Lesion With Treatment With Traditional Chinese Medicine

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. Although surgery is known as the most promising radical treatment, a high recurrent or metastatic rate after surgery has limited its clinical efficacy. Sorafenib, a target agent, has seemed to be the only option for metastatic HCC patients to date, but none of clinical trials showed it could prolong the overall survival (OS) of advanced HCC to 1 year. How to prolong the OS and improve cure rate of HCC patients is still beset with difficulties. This report presents a rare case of recurrent HCC patient with complete regression of target lesion with 2 years of Chinese herbal treatment. A 64-year-old Chinese man with hepatitis B virus–associated chronic hepatitis presented HCC has been clinically diagnosed tumor relapse and omentum metastasis with computed tomography and α-fetoprotein blood test 4 months after surgery. It was decided the patient would receive traditional Chinese medicine treatment because of poor prognosis. After approximately 2 years of treatment, recurrent hepatic tumor and omentum metastasis have been found in complete regression. The patient remains alive over 31 months after relapse.

Optimization and in vitro antiproliferation of Curcuma wenyujin's active extracts by ultrasonication and response surface methodology

Background

Curcuma wenyujin, a member of the genus Curcuma, has been widely prescribed for anti-cancer therapy. Multiple response surface optimization has attracted a great attention, while, the research about optimizing three or more responses employing response surface methodology (RSM) was very few.

Results

RSM and desirability function (DF) were employed to get the optimum ultrasonic extraction parameters, in which the extraction yields of curdione, furanodienone, curcumol and germacrone from C. wenyujin were maximum. The yields in the extract were accurately quantified using the validated high performance liquid chromatography method with a good precision and accuracy. The optimization results indicated that the maximum combined desirability 97.1 % was achieved at conditions as follows: liquid–solid ratio, 8 mL g⁻¹; ethanol concentration, 70 % and ultrasonic time, 20 min. The extraction yields gained from three verification experiments were in fine agreement with those of the model’s predictions. The surface morphologies of the sonication-treated C. wenyujin were loose and rough. The extract of C. wenyujin presented obvious antiproliferative activities against RKO and HT-29 cells in vitro.

Conclusion

Response surface methodology was successfully applied to model and optimize the ultrasonic extraction of four bioactive components from C. wenyujin for antiproliferative activitiy.Graphical abstract

Antiproliferative activity of Curcuma phaeocaulis Valeton extract using ultrasonic assistance and response surface methodology

The objective of the study was to optimize the ultrasonic-assisted extraction of curdione, furanodienone, curcumol, and germacrone from Curcuma phaeocaulis Valeton (Val.) and investigate the antiproliferative activity of the extract. Under the suitable high-performance liquid chromatography condition, the calibration curves for these four tested compounds showed high levels of linearity and the recoveries of these four compounds were between 97.9 and 104.3%. Response surface methodology (RSM) combining central composite design and desirability function (DF) was used to define optimal extraction parameters. The results of RSM and DF revealed that the optimum conditions were obtained as 8 mL g^-1 for liquid-solid ratio, 70% ethanol concentration, and 20 min of ultrasonic time. It was found that the surface structures of the sonicated herbal materials were fluffy and irregular. The C. phaeocaulis Val. extract significantly inhibited the proliferation of RKO and HT-29 cells in vitro. The results reveal that the RSM can be effectively used for optimizing the ultrasonic-assisted extraction of bioactive components from C. phaeocaulis Val. for antiproliferative activity.

Natural Products for Chemoprevention of Breast Cancer

Breast cancer is the primary cause of cancer death in women. Although current therapies have shown some promise against breast cancer, there is still no effective cure for the majority of patients in the advanced stages of breast cancer. Development of effective agents to slow, reduce, or reverse the incidence of breast cancer in high-risk women is necessary. Chemoprevention of breast cancer by natural products is advantageous, as these compounds have few side effects and low toxicity compared to synthetic compounds. In the present review, we summarize natural products which exert chemopreventive activities against breast cancer, such as curcumin, sauchinone, lycopene, denbinobin, genipin, capsaicin, and ursolic acid. This review examines the current knowledge about natural compounds and their mechanisms that underlie breast cancer chemopreventive activity both in vitro and in vivo. The present review may provide information on the use of these compounds for the prevention of breast cancer.