Inhibition of NF-κB translocation by curcumin analogs induces G0/G1 arrest and downregulates thymidylate synthase in colorectal cancer

In vitro additive antitumor effects of dimethoxycurcumin and 5-fluorouracil in colon cancer cells

Dimethoxycurcumin (DMC) is a lipophilic analog of curcumin, an effective treatment for colon cancer, which has greater chemical and metabolic stability. Chemotherapy treatments, such as 5‐fluorouracil (5‐Fu), play a key role in the current management of colon cancer. In this study, we investigated the antitumor efficacy of DMC in combination with 5‐Fu in SW480 and SW620 colon cancer cells. CCK‐8 assay was used to evaluate the inhibitory effect of DMC and 5‐Fu on cancer cells proliferation, and the combination index was calculated. The influence of DMC and 5‐Fu on cell cycle, apoptosis, reactive oxygen species (ROS) production, and mitochondrial membrane potential in SW480 and SW620 cells was determined using flow cytometry, and the related signaling pathways were detected by western blot. Transmission electron microscopy was used to observe endoplasmic reticulum expansion. DMC‐ and/or 5‐Fu‐induced apoptosis, stimulated G0/G1 phase arrest, increased ROS levels, decreased mitochondrial membrane potential, and enhanced endoplasmic reticulum expansion. The induction of apoptosis is involved in the increasing of Bax and cytochrome c and decreasing of Bcl2 expressions. Increased production of ROS was accompanied by upregulation of CHOP and Noxa. Combination therapy of DMC and 5‐Fu had increased efficacy on the above pathways compared with either drug alone. Based on the calculated IC₅₀, combination treatment with DMC and 5‐Fu had an additive antitumor effect in both cell lines. Combined treatment with DMC and 5‐Fu led to an additive antitumor effect in colon cancer cells that was related to apoptosis induction, G0/G1 phase arrest, increased ROS production, decreased mitochondrial membrane potential, and enhanced endoplasmic reticulum expansion.

Curcumin loading potentiates the chemotherapeutic efficacy of selenium nanoparticles in HCT116 cells and Ehrlich's ascites carcinoma bearing mice

The anticancer properties of selenium (Se) and curcumin nanoparticles in solo formulations as well as in combination with other therapeutic agents have been proved time and again. Exploiting this facet of the two, we clubbed their tumoricidal characteristics and designed curcumin loaded Se nanoparticles (Se-CurNPs) to achieve an enhanced therapeutic effect. We evaluated their therapeutic effects on different cancer cell lines and Ehrlich's ascites carcinoma mouse model. In vitro results showed that Se-CurNPs were most effective on colorectal carcinoma cells (HCT116) compared to the other cancer cell lines used and possessed pleiotropic anticancer effects. The therapeutic effect on HCT116 was primarily attributed to an elevated level of autophagy and apoptosis as evident from significant up-regulation of autophagy associated (LC3B-II) and pro-apoptotic (Bax) proteins, down-regulation of anti-apoptotic (Bcl-2) protein and Cytochrome c (cyt c) release from mitochondria along with reduced NFκB signaling and EMT based machineries marked by downregulation of inflammation (NFκB, phospho-NFκB) and epithelial-mesenchymal transition (CD44, N-cadherin) associated proteins. In vivo studies on Ehrlich's ascites carcinoma (EAC) mice model indicated that Se-CurNPs significantly reduced the tumor load and enhanced the mean survival time (days) of tumor-bearing EAC mice.

A Subpopulation of the K562 Cells Are Killed by Curcumin Treatment after G2/M Arrest and Mitotic Catastrophe

Curcumin is extensively investigated as a good chemo-preventive agent in the development of many cancers and particularly in leukemia, including treatment of chronic myelogenous leukemia and it has been proposed as an adjuvant for leukemia therapies. Human chronic myeloid leukemia cells (K562), were treated with 20 μM of curcumin, and we found that a subpopulation of these cells were arrested and accumulate in the G2/M phase of the cell cycle. Characterization of this cell subpopulation showed that the arrested cells presented nuclear morphology changes resembling those described for mitotic catastrophe. Mitotic cells displayed abnormal chromatin organization, collapse of the mitotic spindle and abnormal chromosome segregation. Then, these cells died in an apoptosis dependent manner and showed diminution in the protein levels of BCL-2 and XIAP. Moreover, our results shown that a transient activation of the nuclear factor κB (NFκB) occurred early in these cells, but decreased after 6 h of the treatment, explaining in part the diminution of the anti-apoptotic proteins. Additionally, P73 was translocated to the cell nuclei, because the expression of the C/EBPα, a cognate repressor of the P73 gene, was decreased, suggesting that apoptosis is trigger by elevation of P73 protein levels acting in concert with the diminution of the two anti-apoptotic molecules. In summary, curcumin treatment might produce a P73-dependent apoptotic cell death in chronic myelogenous leukemia cells (K562), which was triggered by mitotic catastrophe, due to sustained BAX and survivin expression and impairment of the anti-apoptotic proteins BCL-2 and XIAP.

Curcumin inhibits placental inflammation to ameliorate LPS-induced adverse pregnancy outcomes in mice via upregulation of phosphorylated Akt

INTRODUCTION

Excessive inflammation results in adverse pregnancy outcomes, including embryonic resorption, fetal growth restriction, and preeclampsia. This study investigated whether curcumin, a highly safe anti-inflammation drug, had protective effect on lipopolysaccharide (LPS)-treated pregnant mice.

METHOD

A mouse model of LPS-induced adverse pregnancy outcomes was generated by daily administering LPS from GD 13.5 to GD 16.5. Curcumin was given from GD 0.5. The effects of curcumin on maternal hypertension, proteinuria, pregnancy outcomes, as well as proinflammatory factors, chemokines, Akt, JNK, and P38 levels in placenta were examined.

RESULTS

Systolic blood pressure (156.6 ± 5.056 versus 125.5 ± 3.617 mmHg; P < 0.05) and proteinuria (22.36 ± 2.22 versus 12.70 ± 1.04 mg/L; P < 0.05) were decreased in the LPS+curcumin-treated group, as compared with the LPS-treated group. Curcumin also increased the number of live pups, fetal weight, and placental weight, while it decreased fetal resorption rate. Moreover, increased placental TNF-α, IL-1β, and IL-6 expressions in LPS-treated group were significantly suppressed after curcumin administration. Furthermore, decreased p-Akt level in placenta induced by LPS was improved by curcumin. Of note, the expression of p-Akt increased by curcumin was accompanied by the decreased chemokines MCP-1 and MIP-1 levels and fewer CD68-positive macrophages in the placenta.

CONCLUSION

Curcumin inhibited the expression of proinflammatory factors and macrophage infiltration in placenta and ameliorated LPS-induced adverse pregnancy outcomes in mice by inhibiting inflammation via upregulation of phosphorylated Akt.

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.

Curcumin suppresses 4-hydroxytamoxifen resistance in breast cancer cells by targeting SLUG/Hexokinase 2 pathway

Triple negative breast cancer (TNBC) is the hardest breast cancer subtype to treat due to lacking therapeutic target and treatment options. In this study, we found that SLUG expression was much higher in TNBC MDA-MB-231 cells than estrogen receptor alpha (ERα) positive breast cancer MCF7 cells. 4-hydroxytamoxifen (4-OHT) promoted SLUG expression, which was blocked by curcumin. Further investigation showed that SLUG activated the transcription of hexokinase-2 (HK2) by binding to HK2 promoter. SLUG knockdown inhibited HK2 expression and weakened 4-OHT resistance of MDA-MB-231 cells. Conversely, SLUG overexpression elevated HK2 level and increased 4-OHT resistance of MCF7 cells. Combination of curcumin and 4-OHT suppressed SLUG and HK2 expression, leading to mitochondrion-mediated apoptosis. These results suggested SLUG as a potential target and curcumin as a promising natural agent for overcoming 4-OHT resistance of TNBC.