RTA dh404 Induces Cell Cycle Arrest, Apoptosis, and Autophagy in Glioblastoma Cells.

RTA dh404 is a novel synthetic oleanolic acid derivative that has been reported to possess anti-allergic, neuroprotective, antioxidative, and anti-inflammatory properties, and exerts therapeutic effects on various cancers. Although CDDO and its derivatives have anticancer effects, the actual anticancer mechanism has not been fully explored. Therefore, in this study, glioblastoma cell lines were exposed to different concentrations of RTA dh404 (0, 2, 4, and 8 µM). Cell viability was evaluated using the PrestoBlue™ reagent assay. The role of RTA dh404 in cell cycle progression, apoptosis, and autophagy was analyzed using flow cytometry and Western blotting. The expression of cell cycle-, apoptosis-, and autophagy-related genes was detected by next-generation sequencing. RTA dh404 reduces GBM8401 and U87MG glioma cell viability. RTA dh404 treated cells had a significant increase in the percentage of apoptotic cells and caspase-3 activity. In addition, the results of the cell cycle analysis showed that RTA dh404 arrested GBM8401 and U87MG glioma cells at the G2/M phase. Autophagy was observed in RTA dh404-treated cells. Subsequently, we found that RTA dh404-induced cell cycle arrest, apoptosis, and autophagy were related to the regulation of associated genes using next-generation sequencing. Our data indicated that RTA dh404 causes G2/M cell cycle arrest and induces apoptosis and autophagy by regulating the expression of cell cycle-, apoptosis-, and autophagy-related genes in human glioblastoma cells, suggesting that RTA dh404 is a potential drug candidate for the treatment of glioblastoma.

Novel Aptamer-Based Small-Molecule Drug Screening Assay to Identify Potential Sclerostin Inhibitors against Osteoporosis.

A novel aptamer-based competitive drug screening platform for osteoporosis was devised in which fluorescence-labeled, sclerostin-specific aptamers compete with compounds from selected chemical libraries for the binding of immobilized recombinant human sclerostin to achieve high-throughput screening for potential small-molecule sclerostin inhibitors and to facilitate drug repurposing and drug discovery. Of the 96 selected inhibitors and FDA-approved drugs, six were shown to result in a significant decrease in the fluorescence intensity of the aptamer, suggesting a higher affinity toward sclerostin compared with that of the aptamer. The targets of these potential sclerostin inhibitors were correlated to lipid or bone metabolism, and several of the compounds have already been shown to be potential osteogenic activators, indicating that the aptamer-based competitive drug screening assay offered a potentially reliable strategy for the discovery of target-specific new drugs. The six potential sclerostin inhibitors suppressed the level of both intracellular and/or extracellular sclerostin in mouse osteocyte IDG-SW3 and increased alkaline phosphatase activity in IDG-SW3 cells, human bone marrow-derived mesenchymal stem cells and human fetal osteoblasts hFOB1.19. Potential small-molecule drug candidates obtained in this study are expected to provide new therapeutics for osteoporosis as well as insights into the structure-activity relationship of sclerostin inhibitors for rational drug design.

The effects of cucurbitacin E on GADD45ß-trigger G2/M arrest and JNK-independent pathway in brain cancer cells.

Cucurbitacin E (CuE), an active compound of the cucurbitacin family, possesses a variety of pharmacological functions and chemotherapy potential. Cucurbitacin E exhibits inhibitory effects in several types of cancer; however, its anticancer effects on brain cancer remain obscure and require further interpretation. In this study, efforts were initiated to inspect whether CuE can contribute to anti-proliferation in human brain malignant glioma GBM 8401 cells and glioblastoma-astrocytoma U-87-MG cells. An MTT assay measured CuE's inhibitory effect on the growth of glioblastomas (GBMs). A flow cytometry approach was used for the assessment of DNA content and cell cycle analysis. DNA damage 45ß (GADD45ß) gene expression and CDC2/cyclin-B1 disassociation were investigated by quantitative real-time PCR and Western blot analysis. Based on our results, CuE showed growth-inhibiting effects on GBM 8401 and U-87-MG cells. Moreover, GADD45ß caused the accumulation of CuE-treated G2/M-phase cells. The disassociation of the CDC2/cyclin-B1 complex demonstrated the known effects of CuE against GBM 8401 and U-87-MG cancer cells. Additionally, CuE may also exert antitumour activities in established brain cancer cells. In conclusion, CuE inhibited cell proliferation and induced mitosis delay in cancer cells, suggesting its potential applicability as an antitumour agent.

Simvastatin induces G1 arrest by up-regulating GSK3ß and down-regulating CDK4/cyclin D1 and CDK2/cyclin E1 in human primary colorectal cancer cells.

Simvastatin (SIM), a widely used cholesterol-lowering drug, also exhibits tumor-suppressive potentials in several types of malignancy. Colorectal cancer (CRC), the third most common malignant neoplasm, accounts for the second most leading cause of cancer-related deaths worldwide. In the present study, we investigated the anticancer effects of SIM on CRC using primary cancer cells lines (CPs: CP1 to CP5) isolated from five Taiwanese colorectal cancer patients as a model for colorectal cancer. We treated all five CPs with SIM for 24-72 hr and observed the respective cell viability by an MTT assay. SIM increased DNA content of the G1 phase, but did not induce apoptosis/necrosis in CPs as shown by flow cytometry with propidium iodide (PI)/annexin V double staining and PI staining. The expression of G1 phase-related proteins was analyzed by RT-PCR and Western blotting. SIM suppressed cell growth and induced cell cycle G1 -arrest by suppressing the expression of CDK4/cyclin D1 and CDK2/cyclin E1, but elevating the expression of glycogen synthase kinase 3ß in CPs. Our findings indicate that SIM may have antitumor activity in established colorectal cancer.

Cyclophosphamide promotes breast cancer cell migration through CXCR4 and matrix metalloproteinases.

Cyclophosphamide is indicated for the treatment of cancerous diseases such as breast cancer and cervical cancer. Recent studies have shown that cyclophosphamide may induce cancer metastasis, but the cause of this unexpected adverse effect is not fully understood. In this study, we investigate the effect of cyclophosphamide on cancer cell migration and its correlation to chemokine (C-X-C motif) receptor 4 (CXCR4), a biomarker for cancer metastasis. Two human cancer cell lines with significant difference in endogenous CXCR4 expression, the breast cancer cell line, MDA-MB-231, and the melanoma cell line, MDA-MB-435S, were treated with various concentrations of cyclophosphamide, followed by the assessment of CXCR4 expression and cell migration. We found that the migration ability of MDA-MB-231 cells was enhanced with increasing concentrations of cyclophosphamide, which induced the cell-surface expression of CXCR4, but had no effect on the overall amount of CXCR4. In MDA-MB-435S cells, in which CXCR4 was barely detectable, cyclophosphamide was unable to activate cell-surface CXCR4, and did not promote cell migration. Studies on the mRNA expression profile of matrix metalloproteinases (MMPs) in MDA-MB-231 cells further indicate that MMP9 and MMP13 may be involved in the action of cyclophosphamide. The protein expression of both MMP9 and MMP13 was increased in the presence of cyclophosphamide. Results from this study provide the molecular basis for the possible pathway of cyclophosphamide to induce cancer metastasis.

Induction of Mitotic Delay in Pharyngeal and Nasopharyngeal Carcinoma Cells Using an Aqueous Extract of Ajuga bracteosa.

Nasopharyngeal carcinoma (NPC) is a common cancer in Southeast Asia, for which radiotherapy and/or chemotherapy are the primary treatment methods. Many herbs are known to have potential uses in chemotherapy; however, the mechanisms underlying the observed antitumor activity of Ajuga bracteosa (AB) against NPC remain unclear. We explored the antitumor effects of AB, which was shown specifically to induce mitotic delay in pharyngeal (Detroit 562) and nasopharyngeal (Hone-1) cancer cells. Proliferation of cancer cells after exposure to aqueous extract of A. bracteosa (AEAB) was assessed using the MTT assay. DNA content and cell cycle arrest induction were analyzed using flow cytometry. The expression of checkpoint kinase 2 (CHK2), cell division control protein 2 (CDC2), and cyclin B1 was investigated using qRT-PCR and Western blot analysis. Results indicated the inhibition of cancer cell growth following exposure to AEAB. In addition, AEAB induced the accumulation of G2/M-phase cells in cancer cell through the disassociation of CDC2/cyclin B1 complex. Our findings suggested that, in addition to the known effects of AEAB in NPC prevention, it may have antitumor activities against NPC cells. In conclusion, AEAB inhibits the growth of and induces mitotic delay in cancer cells, supporting its use as an anticancer agent.

Capsaicin Induces Autophagy and Apoptosis in Human Nasopharyngeal Carcinoma Cells by Downregulating the PI3K/AKT/mTOR Pathway.

Capsaicin is a potential chemotherapeutic agent for different human cancers. In Southeast China, nasopharyngeal carcinoma (NPC) has the highest incidence of all cancers, but final treatment outcomes are unsatisfactory. However, there is a lack of information regarding the anticancer activity of capsaicin in NPC cells, and its effects on the signaling transduction pathways related to apoptosis and autophagy remain unclear. In the present study, the precise mechanisms by which capsaicin exerts anti-proliferative effects, cell cycle arrest, autophagy and apoptosis were investigated in NPC-TW01 cells. Exposure to capsaicin inhibited cancer cell growth and increased G1 phase cell cycle arrest. Western blotting and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) were used to measure capsaicin-induced autophagy via involvement of the class III PI3K/Beclin-1/Bcl-2 signaling pathway. Capsaicin induced autophagy by increasing levels of the autophagy markers LC3-II and Atg5, enhancing p62 and Fap-1 degradation and increasing caspase-3 activity to induce apoptosis, suggesting a correlation of blocking the PI3K/Akt/mTOR pathway with the above-mentioned anticancer activities. Taken together, these data confirm that capsaicin inhibited the growth of human NPC cells and induced autophagy, supporting its potential as a therapeutic agent for cancer.

Low-dose metronomic chemotherapy with cisplatin enhanced immunity in a murine model of ectopic cervical cancer.

Previous researchers have claimed that metronomic low-dose/dense chemotherapy can enhance the therapeutic effectiveness of cisplatin treatment in the control of cancer. Therefore, the aim of this study was to explore the effectiveness of metronomic drug delivery with regards to its effects on adaptive immunity in a murine model of ectopic cervical cancer. The effectiveness of long-term low-dose/dense cisplatin treatment in HPV E7-expressing TC-1 cells was evaluated via morphological observations. Tumour mass and survival curves were used to determine the antitumour effect against E7-expressing tumours. After experimental mice had been treated with low-dose/dense cisplatin therapy, flow cytometry was used to measure the expression of MHC class I surface antigens on cultured TC-1 cells. Splenocytes expressing both interferon (IFN)-γ and CD8 responsible for E7 antigens and the Treg population were also quantified using flow cytometry. The results indicate that in vivo treatment with metronomic cisplatin suppresses the growth of cultured TC-1 cells. An increase was also observed in the number of splenocytes expressing both IFN-γ and CD8 responsible for E7 antigens and the Treg population. These results support previous reports that metronomic low-dose/dense cisplatin chemotherapy is an effective treatment against ectopic cervical cancer with E7-expression.

Sulforaphane, a Dietary Isothiocyanate, Induces G2/M Arrest in Cervical Cancer Cells through CyclinB1 Downregulation and GADD45ß/CDC2 Association.

Globally, cervical cancer is the most common malignancy affecting women. The main treatment methods for this type of cancer include conization or hysterectomy procedures. Sulforaphane (SFN) is a natural, compound-based drug derived from dietary isothiocyanates which has previously been shown to possess potent anti-tumor and chemopreventive effects against several types of cancer. The present study investigated the effects of SFN on anti-proliferation and G2/M phase cell cycle arrest in cervical cancer cell lines (Cx, CxWJ, and HeLa). We found that cytotoxicity is associated with an accumulation of cells in the G2/M phases of the cell-cycle. Treatment with SFN led to cell cycle arrest as well as the down-regulation of Cyclin B1 expression, but not of CDC2 expression. In addition, the effects of GADD45ß gene activation in cell cycle arrest increase proportionally with the dose of SFN; however, mitotic delay and the inhibition of proliferation both depend on the dosage of SFN used to treat cancer cells. These results indicate that SFN may delay the development of cancer by arresting cell growth in the G2/M phase via down-regulation of Cyclin B1 gene expression, dissociation of the cyclin B1/CDC2 complex, and up-regulation of GADD45ß proteins.

Melatonin Suppresses the Growth of Ovarian Cancer Cell Lines (OVCAR-429 and PA-1) and Potentiates the Effect of G1 Arrest by Targeting CDKs.

Melatonin is found in animals as well as plants. In animals, it is a hormone that anticipates the daily onset of darkness and regulates physiological functions, such as sleep timing, blood pressure, and reproduction. Melatonin has also been found to have anti-tumor properties. Malignant cancers are the most common cause of death, and the mortality rate of ovarian tumor is the highest among gynecological diseases. This study investigated the anti-tumor effects of melatonin on the ovarian cancer lines, OVCAR-429 and PA-1. We observed the accumulation of melatonin-treated cells in the G1 phase due to the down-regulation of CDK 2 and 4. Our results suggest that in addition to the known effects on prevention, melatonin may also provide anti-tumor activity in established ovarian cancer.

Induction of Apoptosis in Endometrial Cancer (Ishikawa) Cells by Pogostemon cablin Aqueous Extract (PCAE).

Pogostemon cablin (PC) is a traditional herbal medicine used in the treatment of the common cold, nausea, diarrhea, and even for headaches and fever. However, the mechanisms underlying the anti-proliferative activity of PC in endometrial cancer (EC) cells have yet to be fully elucidated. This study investigated the anticancer effects of an aqueous extract of Pogostemon cablin (PCAE), specifically induced apoptosis in EC (Ishikawa) cells. Proliferation of EC cells following exposure to PCAE was assessed by an MTT assay. DNA content and the induction of cell cycle apoptosis were analyzed by flow cytometry (FACS Calibur). Protein caspase-3 and, -9 as well as AIF were investigated using Western blot. Our results demonstrate growth inhibition of Ishikawa cells by PCAE. Furthermore, caspase-3 activity caused PCAE-treated cell lines to accumulate in apoptosis. Gene expression profiling (GEP) results further suggest that, in addition to its known effects with regard to EC prevention, PCAE may also exert antitumor activity on established EC cells. Many previous studies have identified the chemo-preventive effects of natural plant materials and the potential role of these materials in chemotherapy. This current study used human EC Ishikawa cells to investigate the anti-tumor effects of PCAE in EC cells. Our results demonstrate that PCAE inhibits the growth of cancer cells and induces apoptosis, which suggests the potential applicability of PCAE as an antitumor agent.

Hepatoma-derived growth factor upregulation is correlated with prognostic factors of early-stage cervical adenocarcinoma.

Hepatoma-derived growth factor (HDGF) is a unique nuclear/growth factor that plays an important role in the progression of different types of cancer. A total of 63 patients with early-stage cervical adenocarcinoma (Cx) were enrolled in this retrospective study. The expression of HDGF was significantly increased compared with adjacent non-tumor tissue samples (p < 0.001). Moreover, elevated nuclear HDGF levels were correlated with lymph-vascular space invasion (LVSI; p < 0.05), lymph node metastasis (LNM; p < 0.001), recurrence (p < 0.001) and advanced grade (AG; p < 0.001). The growth of cervical cancer cells (Hela cells) was enhanced by HDGF treatment. The HDGF mRNA and protein level were significantly higher in malignant cervical cancer cells compared with primary ones. By adenovirus gene delivery, HDGF overexpression enhanced, whereas HDGF knockdown perturbed the tumorigenic behaviors of cervical cancer cells. HDGF overexpression is common in early-stage cervical adenocarcinoma and is involved in the carcinogenesis of cervical adenocarcinoma. Cytoplasmic HDGF expression is strongly correlated with pelvic lymph node metastasis and recurrence, indicating that HDGF may serve as a novel prognostic marker for patients with Cx.

Exogenous polyamines promote osteogenic differentiation by reciprocally regulating osteogenic and adipogenic gene expression.

Polyamines are naturally occurring organic polycations that are ubiquitous in all organisms, and are essential for cell proliferation and differentiation. Although polyamines are involved in various cellular processes, their roles in stem cell differentiation are relatively unexplored. In this study, we found that exogenous polyamines, putrescine, spermidine, and spermine, promoted osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) without inducing cell death or apoptosis. Alkaline phosphatase (ALP) activity and the mRNA level of osteogenic genes, including Runx2, ALP, osteopontin, and osteocalcin, were up-regulated by exogenous polyamines. When hBMSCs were cultured at high cell density favoring adipocyte formation, exogenous polyamines resulted in down-regulation of adipogenic genes such as PPARγ, aP2, and adipsin. Extracellular matrix mineralization, a marker for osteoblast maturation, was enhanced in the presence of exogenous polyamines, while lipid accumulation, an indication of adipogenic differentiation, was attenuated. Exogenous polyamines increased the mRNA expression of polyamine-modulated factor 1 (PMF-1) and its downstream effector, spermidine/spermine N(1)-acetyltransferase (SSAT), while that of ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis, was suppressed. These results lead to possible connections between polyamine metabolism and osteogenic differentiation pathways. To summarize, this study provides evidence for the involvement of polyamines in osteogenic differentiation of hBMSCs, and is the first to demonstrate that osteogenic and adipogenic differentiation are reciprocally regulated by exogenous polyamines.

Cucurbitacin E as inducer of cell death and apoptosis in human oral squamous cell carcinoma cell line SAS.

Human oral squamous cell carcinoma (OSCC) is a common form of malignant cancer, for which radiotherapy or chemotherapy are the main treatment methods. Cucurbitacin E (CuE) is a natural compound previously shown to be an antifeedant as well as a potent chemopreventive agent against several types of cancer. The present study investigates anti-proliferation (using MTT assay, CuE demonstrated cytotoxic activity against SAS cell with IC50 values at 3.69 µM) and induced apoptosis of human oral squamous cell carcinoma SAS cells after 24 h treatment with CuE. Mitochondrial membrane potential (MMP) and caspase activity were studied and our results indicate that CuE inhibits cell proliferation as well as the activation of apoptois in SAS cells. Both effects increased in proportion to the dosage of CuE and apoptosis was induced via mitochondria- and caspase-dependent pathways. CuE can induce cell death by a mechanism that is not dependent on apoptosis induction, and thus represents a promising anticancer agent for prevention and treatment of OSCC.

Preclinical Activity of Simvastatin Induces Cell Cycle Arrest in G1 via Blockade of Cyclin D-Cdk4 Expression in Non-Small Cell Lung Cancer (NSCLC).

Lung cancer is the most common cause of cancer-related death. Nonetheless, a decrease in overall incidence and mortality has been observed in the last 30 years due to prevention strategies and improvements in the use of chemotherapeutic agents. In recent studies, Simvastatin (SIM) has demonstrated anti-tumor activity, as well as potent chemopreventive action. As an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA), SIM has been shown to stimulate apoptotic cell death. In this study, an MTT assay revealed the cytotoxic activity of SIM against human large cell lung cancer (Non-small cell lung cancer; NSCLC) cells (NCI-H460); however, induced apoptosis was not observed in NCI-H460 cells. Protein expression levels of cell cycle regulating proteins Cdk4, Cyclin D1, p16 and p27 were markedly altered by SIM. Collectively, our results indicate that SIM inhibits cell proliferation and arrests NCI-H460 cell cycle progression via inhibition of cyclin-dependent kinases and cyclins and the enhancement of CDK inhibitors p16 and p27. Our findings suggest that, in addition to the known effects on hypercholesterolemia therapy, SIM may also provide antitumor activity in established NSCLC.

JSI-124 Induces Cell Cycle Arrest and Regulates the Apoptosis in Glioblastoma Cells.

Cucurbitacin I (JSI-124), derived from Cucurbitaceae, has shown the potential to induce apoptosis and cell cycle arrest in some cancer cells. However, the effect of JSI-124 on glioblastoma multiforme (GBM) cell cycle and apoptosis is still unclear. Our investigation revealed that JSI-124 effectively reduced cell viability in GBM cells, leading to apoptosis and increased caspase-3 activity. Intriguingly, JSI-124 caused the accumulation of G2/M phase to regulate cell cycle, confirmed by MPM-2 staining and increased protein synthesis during mitosis by mitotic index analysis. Western blot analysis found that JSI-124 affected the progression of G2/M arrest by downregulating the CDK1 and upregulating the cyclinB1, suggesting that JSI-124 disrupted the formation and function of the cyclin B1/CDK1 complex in GBM8401 and U87MG cells. However, we found the JSI-124-regulated cell cycle G2/M and apoptosis-relative gene in GBM8401 and U87MG cells by NGS data analysis. Notably, we found that the GBM8401 and U87MG cells observed regulation of apoptosis and cell-cycle-related signaling pathways. Taken together, JSI-124 exhibited the ability to induce G2/M arrest, effectively arresting the cell cycle at critical stages. This arrest is accompanied by the initiation of apoptosis, highlighting the dual mechanism of action of JSI-124. Collectively, our findings emphasize that JSI-124 holds potential as a therapeutic agent for GBM by impeding cell cycle progression, inhibiting cell proliferation, and promoting apoptosis. As demonstrated by our in vitro experiments, these effects are mediated through modulation of key molecular targets.

Sulforaphane-Induced Cell Mitotic Delay and Inhibited Cell Proliferation via Regulating CDK5R1 Upregulation in Breast Cancer Cell Lines.

Our research has revealed that sulforaphane (SFN) has chemopreventive properties and could be used in chemotherapy treatments. Further investigation is needed to understand the mechanisms behind sulforaphane's (SFN) antitumor activity in breast adenocarcinoma, as observed in our studies. This research looked into the effects of SFN on mitosis delay and cell cycle progression in MDA-MB-231 and ZR-75-1 cells, two types of triple-negative breast cancer adenocarcinoma.The proliferation of the cancer cells after SFN exposure was evaluated using MTT assay, DNA content and cell cycle arrest induction by flow cytometry, and expressions of cdc25c, CDK1, cyclin B1 and CDK5R1 were assessed through qRT-PCR and Western blot analysis. SFN was found to inhibit the growth of cancer cells. The accumulation of G2/M-phase cells in SFN-treated cells was attributed to CDK5R1. The disruption of the CDC2/cyclin B1 complex suggested that SFN may have antitumor effects on established breast adenocarcinoma cells. Our findings suggest that, in addition to its chemopreventive properties, SFN could be used as an anticancer agent for breast cancer, as it was found to inhibit growth and induce apoptosis of cancer cells.

A Novel Synthetic Oleanolic Acid Derivative Inhibits Glioma Cell Proliferation by Regulating Cell Cycle G2/M Arrest.

2-Cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid-9,11-dihydro-trifluoroethyl amide (CDDO-dhTFEA) has antioxidant and anti-inflammatory activities; however, whether CDDO-dhTFEA has anticancer effects is unclear. The objective of this research was to investigate the possibility of CDDO-dhTFEA as a potential cancer-fighting treatment in glioblastoma cells. Our experiments were performed on U87MG and GBM8401 cells, and we found that CDDO-dhTFEA was effective in reducing cell proliferation in both cell lines, in a manner that was dependent on both time and concentration. Additionally, we observed that CDDO-dhTFEA had a significant impact on the regulation of cell proliferation, which was evident in the increase in DNA synthesis that was observed in both cell types. CDDO-dhTFEA induced G2/M cell cycle arrest and mitotic delay, which may be associated with the inhibition of proliferation. Treatment with CDDO-dhTFEA led to cell cycle G2/M arrest and inhibited proliferation of U87MG and GBM8401 cells by regulating G2/M cell cycle proteins and gene expression in GBM cells in vitro.

In vitro biocompatibility of thermally gelling liquid mucoadhesive loaded curcuminoids in colorectal cancer chemoprevention.

PURPOSE: Colorectal cancer (CRC) is the third leading cause of cancer death in Taiwan; it ranks top three in the cancer mortality rate. Curcuminoids are derived from the rhizome of Curcuma longa. It has shown anti-cancer activity and apoptosis induction in a variety of cancer cell lines. This aims to study the potential of Poloxamer 407 as the thermogelling and mucoadhesive polymer for development of a site-targeting delivery system to enhance the localized delivery of curcuminoids to the colorectal cells for CRC chemotherapy. METHODS: The mucoadhesive strength and rheological properties were measured as a function of poloxamer loaded with curcuminoids. RESULTS: The gelation temperature of Poloxamer 407 was found to vary with its concentration and start gelling at 37°C at the concentration of 15.5% (w/v). To ensure gelation at physiological temperature after intra-rectal application, gelation temperature was determined by rheological measurement as well as by its physical appearance. The results indicated that its mucoadhesive strength also shows a dependency on temperature, which appears to be related to the increment in the maximum strength and average strength of the polymer. CONCLUSION: The results have suggested that Poloxamer 407 could be a potential thermogelling and mucoadhesive polymer for the development of a site-targeting colorectal drug delivery system for curcuminoids in colorectal cancer therapy.

Demethoxycurcumin Retards Cell Growth and Induces Apoptosis in Human Brain Malignant Glioma GBM 8401 Cells.

Demethoxycurcumin (DMC; a curcumin-related demethoxy compound) has been recently shown to display antioxidant and antitumor activities. It has also produced a potent chemopreventive action against cancer. In the present study, the antiproliferation (using the MTT assay, DMC was found to have cytotoxic activities against GBM 8401 cell with IC(50) values at 22.71 µM) and induced apoptosis effects of DMC have been investigated in human brain malignant glioma GBM 8401 cells. We have studied the mitochondrial membrane potential (MMP), DNA fragmentation, caspase activation, and NF-κB transcriptional factor activity. By these approaches, our results indicated that DMC has produced an inhibition of cell proliferation as well as the activation of apoptosis in GBM 8401 cells. Both effects were observed to increase in proportion with the dosage of DMC treatment, and the apoptosis was induced by DMC in human brain malignant glioma GBM 8401 cells via mitochondria- and caspase-dependent pathways.