Luffa echinata Roxb. induces human colon cancer cell (HT-29) death by triggering the mitochondrial apoptosis pathway

Unveiling the anticancer potential of Anamirta cocculus (L.) Wight& Arn.: Evidences from cytotoxicity studies, apoptosis analysis, and molecular docking

Anamirta cocculus, a woody climber, is extensively utilised in traditional Asian medicine. This study investigates the cytotoxic effects of A. cocculus leaf extracts on various cancer cell lines as well as on a normal cell line. The ethyl acetate extract exhibited potent anticancer activity, with the highest cytotoxicity observed against ovarian cancer cell line (PA1) (IC50 = 8.30 ± 0.38 µg/mL) and colorectal adenocarcinoma cell line (HT29) (IC50 = 17.97 ± 0.63 µg/mL). Notably, the extract displayed low toxicity (18.72 ± 0.73%) on the normal human keratinocyte cell line (HaCaT) at a concentration of 100 µg/mL, indicating selective cytotoxicity towards cancer cells. The acetone extract also demonstrated significant cytotoxicity against various cancer cell lines, including A498, MG63, PA1, and UM-SCC-83B. The ethyl acetate extract of A. cocculus demonstrated potent inhibition of colony formation in HT29 and PA1 cancer cell lines while inducing apoptosis, as evidenced by membrane blebbing, chromatin condensation, and DNA fragmentation. The number of late apoptotic cells increased with an increase in concentrations of ACLE. Molecular docking studies of compounds identified through GC-MS analysis revealed strong interactions with key apoptotic proteins, including caspase-8, p53, caspase-3, and caspase-9. Compounds such as vitamin E, epoxylathyrol, squalene, and phytol showed high binding affinity to these proteins, suggesting their role in apoptosis induction. The possibility of induction of apoptotic proteins through indirect interaction by binding to other proteins or receptors cannot be ruled out. The cytotoxic effects may result from individual, combined, or synergistic actions of these compounds. Among these, epoxylathyrol emerged as a particularly promising anticancer drug candidate based on ADME analysis and binding affinity assessments, warranting further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-04096-2.

Review On Documented Medicinal Plants Used For The Treatment Of Cancer

Background:

Cancer is a frightful disease and it is the second leading cause of death worldwide. Naturally derived compounds are gaining interest of research workers as they have less toxic side effects as compared to currently used treatments such as chemotherapy. Plants are the pool of chemical compounds which provides a promising future for research on cancer.

Objective:

This review paper provides updated information gathered on medicinal plants and isolated phytoconstituents used as anticancer agents and summarises the plant extracts and their isolated chemical constituents exhibiting anticancer potential on clinical trials.

Methods:

An extensive bibliographic investigation was carried out by analysing worldwide established scientific databases like SCOPUS, PUBMED, SCIELO, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar etc. In next few decades, herbal medicine may become a new epoch of medical system.

Results:

Many researches are going on medicinal plants for the treatment of cancer but it is a time to increase further experimental studies on plant extracts and their chemical constituents to find out their mechanism of action at molecular level.

Conclusion:

The article may help many researchers to start off further experimentation that might lead to the drugs for the cancer treatment.

In vitro evidence of the antitumor capacity of Solanaceae and Cucurbitaceae in colon cancer: A systematic review

Colon cancer is the fourth leading cause of cancer deaths around the world. Despite advances in understanding its etiology and in diagnosis and treatment, new therapeutic strategies are still required. In this sense, the Solanaceae and Cucurbitaceae families have been widely used to treat various pathologies, including cancer, for their bioactive components. The objective of this systematic review was to analyze the antitumor activity of the bioactive components present in extracts from Solanaceae and Cucurbitaceae families using different in in vitro models of colon cancer. 241 publications have been identified (published from January 2008 to January 2020) from different electronic data base. 44 articles were included, 26 of which examined the Solanaceae family. The antitumor activity exhibited by this family was due to the withanolide-type steroid compounds they harbor. 18 articles were related to the Cucurbitaceae family. This family is characterized by their production of cucurbitacin-type triterpenoid compounds and their derivatives, which confer antitumor activity. In conclusion, the different genera belonging to both families are an important source of bioactive compounds with relevant activity against colon cancer. More experimental and in vivo studies will be required to corroborate their antitumor activity and to leverage them in future clinical practice.

Construction of a high-density genetic linkage map and identification of gene controlling resistance to cucumber mosaic virus in Luffa cylindrica (L.) Roem. based on specific length amplified fragment sequencing

Luffa cylindrica L. is a cash crop which has important health, medicinal and industrial value, but no high saturation genetic map has been constructed owing to a lack of efficient markers. Furthermore, no genes were reportedly responsible for CMV resistance in Luffa spp. Specific length amplified fragment sequencing (SLAF-seq) is a valuable tool for large-scale discovery of markers and genetic mapping. The present study reported the construction of a high-density genetic map and the mapping of CMV resistant genes by using an F₂ population of 130 individuals and their two inbred line parents. A total of 271.01 Mb pair-end reads were generated. 100,077 high-quality SLAFs were detected, and 7404 of them were polymorphic. Finally, 3701 of the polymorphic markers were selected for genetic map construction, and 13 linkage groups were generated. The map spanned 1518.56 cM with an average distance of 0.41 cM between adjacent markers. Based on the newly constructed high-density map, one gene located on chromosome 1 (100.072-100.457 cM) was identified to regulate CMV resistance in L. cylindrica. A gag-polypeptide of LTR copia-type retrotransposon was predicted as the candidate gene responsible for CMV resistance in L. cylindrica. The high-density genetic map and the CMV resistant gene mapped and predicted in this study will be useful in future research.

Medicinal Plants in the Prevention and Treatment of Colon Cancer

The standard treatment for cancer is generally based on using cytotoxic drugs, radiotherapy, chemotherapy, and surgery. However, the use of traditional treatments has received attention in recent years. The aim of the present work was to provide an overview of medicinal plants effective on colon cancer with special emphasis on bioactive components and underlying mechanisms of action. Various literature databases, including Web of Science, PubMed, and Scopus, were used and English language articles were considered. Based on literature search, 172 experimental studies and 71 clinical cases on 190 plants were included. The results indicate that grape, soybean, green tea, garlic, olive, and pomegranate are the most effective plants against colon cancer. In these studies, fruits, seeds, leaves, and plant roots were used for in vitro and in vivo models. Various anticolon cancer mechanisms of these medicinal plants include induction of superoxide dismutase, reduction of DNA oxidation, induction of apoptosis by inducing a cell cycle arrest in S phase, reducing the expression of PI3K, P-Akt protein, and MMP as well; reduction of antiapoptotic Bcl-2 and Bcl-xL proteins, and decrease of proliferating cell nuclear antigen (PCNA), cyclin A, cyclin D1, cyclin B1 and cyclin E. Plant compounds also increase both the expression of the cell cycle inhibitors p53, p21, and p27, and the BAD, Bax, caspase 3, caspase 7, caspase 8, and caspase 9 proteins levels. In fact, purification of herbal compounds and demonstration of their efficacy in appropriate in vivo models, as well as clinical studies, may lead to alternative and effective ways of controlling and treating colon cancer.

Potent antitumor property of Allium bakhtiaricum extracts

BACKGROUND

Allium species are magnificently nutritious and are commonly used as a part of the diet in Iran. They have health enhancing benefits including anticancer properties due to the presence of numerous bioactive compounds. Herein, we investigated in vitro and in vivo anticancer properties of Allium bakhtiaricum extracts.

METHODS

Anti-growth activity of different fractions was explored in vitro on different cancerous cells using MTT assay, Annexin V/PI and SA-β-gal staining, Western blotting, flowcytometric and immunofluorescence microscopic evaluations. In vivo antitumor activity was investigated in BALB/c mice bearing 4 T1 mammary carcinoma cells.

RESULTS

We demonstrated that chloroformic and ethyl acetate fractions exert cytotoxic activity toward MDA-MB-231 cells, the most sensitive cell line, after 72 h of treatment with IC₅₀ values of 0.005 and 0.006 mg/ml, respectively. Incubation of MDA-MB-231 cells with ¼ and ½ IC_50-72h concentrations of each fraction resulted in a significant G2/M cell cycle arrest. ¼ IC_50-72h concentration of the chloroform fraction led to the disruption of polymerization in mitotic microtubules. Exposure of human breast cancer cells to different concentrations of the extracts at different incubation times did not induce apoptosis, autophagy or senescence. Our in vivo study revealed that administration of the chloroform extract at a dose of 1 mg/kg/day strongly suppressed mammary tumor progression and decreased the number of proliferative cells in the lung tissues indicating its anti-metastatic effect.

CONCLUSION

Our findings imply that the chloroform fraction of Allium bakhtiaricum possesses the suppressive action on breast cancer through mitotic cell cycle arrest suggesting a mechanism associated with disturbing microtubule polymerization.

Exopolysaccharides produced by Lactobacillus strains suppress HT-29 cell growth via induction of G0/G1 cell cycle arrest and apoptosis

In the present study, the effects of exopolysaccharides (EPS) from nine Lactobacillus strains with a high degree of bio-activity on human colon cancer cell line HT-29 were studied. The extracellular polymeric substances from 4 strains, namely K11, M5, SB27 and ×12, displayed desirable anti-proliferative activity against HT-29 cells. Crude and acidic EPS were purified from the 4 strains and the inhibitory effects were further investigated. The crude and acidic EPS from these 4 strains exerted anti-proliferation effects on HT-29 cells in a dose-dependent manner but were nontoxic to Vero cells. Treatment with EPS significantly induced G0/G1 cell cycle arrest and apoptosis of HT-29 cells. Hoechst 33258 staining of acidic EPS-treated HT-29 cells revealed different degrees of morphological changes within the nucleus and the formation of apoptotic bodies. Caspase-3 activity was markedly upregulated in HT-29 cells following treatment with acidic EPS. In addition, acidic EPS from the SB27 strain demonstrated the most robust inhibitory effect on HT-29 cells. The results of the present study suggest that as an inducer of apoptosis EPS has the potential to be applied in the treatment of colorectal cancer.

Xihuang Pill Induces Apoptosis of Human Glioblastoma U-87 MG Cells via Targeting ROS-Mediated Akt/mTOR/FOXO1 Pathway

Xihuang pill (XHP), a traditional Chinese herbal formula, has long been used as an effective agent against multiple tumors. The aim of this study is to evaluate the effects of XHP on the growth inhibition and apoptosis in glioblastoma U-87 MG cells. Gas chromatography-mass spectrometry (GC-MS) was performed for constituent analysis of XHP. Cell viability, cell cycle arrest, generation of reactive oxygen species (ROS), and apoptosis were measured by CCK-8 assay, PI/RNase staining, DCFH-DA assay, TUNEL assay, Annexin V-FITC/PI double staining, and JC-1 assay, respectively. The role of XHP in the regulation of Akt/mTOR/FOXO1 interaction was clarified by using Western Blotting (WB), immunofluorescence (IF), pharmacological inhibitor or antioxidant, and siRNA silencing. The results suggested that XHP could inhibit U-87 MG cells growth and arrest cells in S-phase cell cycle significantly and that the generation of ROS, collapse of mitochondrial membrane potential, enhancement of Bax/Bcl-xL ratio, and reduction of the precursor forms of caspase-9 and caspase-3 caused by XHP prompted that a ROS-mediated mitochondria-dependent apoptosis was possibly involved. Furthermore, XHP affected the Akt/mTOR/FOXO1 pathway via inhibiting the phosphorylation of Akt, mTOR, and FOXO1 and increasing both prototype and nuclear translocation of FOXO1. Inhibition of Akt, mTOR, and FOXO1 by specific inhibitors or siRNA could interpose the apoptotic induction. In conclusion, we demonstrate for the first time that XHP may regulate glioblastoma U-87 MG cell apoptosis via ROS-mediated Akt/mTOR/FOXO1 pathway.

In vitro Antiproliferative and Apoptosis Inducing Effect of Allium atroviolaceum Bulb Extract on Breast, Cervical, and Liver Cancer Cells

Natural products are considered potent sources for novel drug discovery and development. The multiple therapeutic effects of natural compounds in traditional medicine motivate us to evaluate the cytotoxic activity of bulb of Allium atroviolaceum in MCF7 and MDA-MB-231, HeLa and HepG2 cell lines. The bulb methanol extract of A. atroviolaceum was found to be an active cell proliferation inhibitor at the time and dose dependent manner. Determination of DNA content by flow cytometry demonstrated S and G2/M phase arrest of MCF-7 cell, correlated to Cdk1 downregulation, S phase arrest in MDA-MB-231 which is p53 and Cdk1-dependent, sub-G0 cell cycle arrest in HeLa aligned with Cdk1 downregulation, G0/G1, S, G2/M phase arrest in HepG2 which is p53-dependent. Apoptosis as the mechanism of cell death was confirmed by morphology study, caspases activity assay, as well as apoptosis related gene expression, Bcl-2. Caspase-8, -9, and -3 activity with downregulation of Bcl-2 illustrated occurrence of both intrinsic and extrinsic pathways in MCF7, while caspase-3 and -8 activity revealed extrinsic pathway of apoptosis, although Bcl-2 downregulated. In HeLa cells, the activity of caspase-9 and -3 and downregulation of Bcl-2 shows intrinsic pathway or mitochondrial pathway, whereas HepG2 shows caspase independent apoptosis. Further, the combination of the extract with tamoxifen against MCF7 and MDA-MB-231 and combination with doxorubicin against HeLa and HeG2 demonstrated synergistic effect in most concentrations, suggests that the bulb of A. atroviolaceum may be useful for the treatment of cancer lonely or in combination with other drugs.

Phytoconstituents as apoptosis inducing agents: strategy to combat cancer

Advancement in the field of cancer molecular biology has aided researchers to develop various new chemopreventive agents which can target cancer cells exclusively. Cancer chemopreventive agents have proficiency to inhibit, reverse and delay process of carcinogenesis during its early and later course. Chemopreventive agents can act as antioxidative, antimutagenic/antigenotoxic, anti-inflammatory agents or via aiming various molecular targets in a cell to induce cell death. Apoptosis is a kind of cell death which shows various cellular morphological alterations such as cell shrinkage, blebbing of membrane, chromatin condensation, DNA fragmentation, formation of apoptotic bodies etc. Nowadays, apoptosis is being one of the new approaches for the identification and development of novel anticancer therapies. For centuries, plants are known to play part in daily routine from providing food to management of human health. In the last two decades, diverse phytochemicals and various botanical formulations have been characterized as agents that possess potential to execute cancer cells via inducing apoptosis. Data obtained from the research carried out globally pointed out that natural products are the potential candidates which have capability to combat cancer. In the present review, we surveyed literature on natural products which throws light on the mechanism through which these phytochemicals induce apoptosis in cancer cells.

Luffa echinata Roxb. Induced Apoptosis in Human Colon Cancer Cell (SW-480) in the Caspase-dependent Manner and Through a Mitochondrial Apoptosis Pathway

BACKGROUND

Luffa echinata Roxb. (LER) (Cucurbitaceae) showed tremendous medicinal importance and are being used for the treatment of different ailments.

OBJECTIVE

In this study, the antiproliferative properties and cell death mechanism induced by the extract of the fruits of LER were investigated.

MATERIALS AND METHODS

MTT and LDH assay were used to test the antiproliferative and cytotoxicity of LER extract, respectively. The intracellular ROS were measured by a fluorometric assay. The expression of several apoptotic-related proteins in SW-480 cells treated by LER was evaluated by Western blot analysis.

RESULTS

The methanolic extract of LER fruits inhibited the proliferation of human colon cancer cells (SW-480) in both dose- and time-dependent manners. The LER-treated cells showed obvious characteristics of cell apoptosis, including cell shrinkage, destruction of the monolayer, and condensed chromatin. In addition, treatments of various concentrations of LER extracts caused the release of lactate dehydrogenase as a dose-dependent manner via stimulation of the intracellular metabolic system. LER induced apoptosis, DNA fragmentation, and cellular ROS accumulation in SW-480 cells. Treatment of LER on SW-480 cells promoted the expression of caspases, Bax, Bad, and p53 proteins and decreased the levels of Bcl-2 and Bcl-XL.

CONCLUSIONS

These results indicated that treatment with LER-induced cell death in mitochondrial apoptosis pathway by regulating pro-apoptotic proteins via the up regulation of the p53 protein. These findings highlight the potentials of LER in the treatment of human colon cancer.

SUMMARY

LER induced apoptosis, DNA fragmentation, and cellular ROS accumulation in SW-480 cells. Treatment of LER on SW-480 cells promoted the expression of caspases, Bax, Bad, and p53 proteins and decreased the levels of Bcl-2 and Bcl-XL.

Polypeptide Fraction from Arca subcrenata Induces Apoptosis and G2/M Phase Arrest in HeLa Cells via ROS-Mediated MAPKs Pathways

Arca subcrenata is documented in the literature of marine Traditional Chinese Medicine. Polypeptide fraction from A. subcrenata, coded as P2, was demonstrated to possess significant antitumor activity in our previous study. However, the underlying mechanism remains undefined. The present study was carried out to investigate the underlying antitumor mechanism of P2 in human cervical cancer HeLa cells by MTT, FCM, LSCM, and western blot assays. The results revealed that P2 significantly induced apoptosis of HeLa cells in a concentration- and time-dependent manner. High level of ROS was provoked by P2, which was in turn responsible for induction of apoptosis through activation of intrinsic mitochondrial pathway and JNK1/2, p38 MAPK pathways, as well as inhibition of ERK1/2 pathway, as evidenced by the abrogation of P2's effect on HeLa cells preincubated with the ROS scavenger NAC. P2 also was observed to display significant effect on G2/M phase arrest by downregulating the expression of cyclin B1/cdc2 complex and upregulating the expression of p21. These findings demonstrate that P2 induces apoptosis and G2/M phase arrest in HeLa cells through ROS-mediated MAPKs pathways, suggesting that P2 would be worth investigating as a promising agent within the scope of marine drugs for treatment of cervical cancer.

Apoptosis of human non-small-cell lung cancer A549 cells triggered by evodiamine through MTDH-dependent signaling pathway

Metadherin (MTDH), a novel oncoprotein, has been implicated in the carcinogenesis in various aspects of tumor malignancy. Overexpression of the MTDH promotes the survival and proliferation of lung cancer cells. Agent that can suppress MTDH activation would have potential to be developed for cancer therapeutics. In this study, we investigated the antitumor effect of evodiamine in human non-small-cell lung carcinoma (NSCLC) A549 cell line and the inhibitory effect of evodiamine on MTDH pathway. 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and annexin V/propidium iodide (PI) staining assays demonstrated that evodiamine or MTDH short hairpin RNA (shRNA) significantly inhibited proliferation of A549 cells via induction of apoptosis. Besides, evodiamine or MTDH shRNA-induced activation of the caspase-3 in A549 cells under same conditions. In addition, Western blotting analysis showed that treatment of A549 cells with evodiamine or MTDH shRNA resulted in an increase of proapoptotic protein Bax expression but decreased the expression levels of antiapoptotic protein Bcl-2 and MTDH, which altogether account for apoptotic cell death. Taken together, our results suggest that the evodiamine suppress the proliferation of lung cancer cells, at least, in part, via inhibition of MTDH expression and activation of apoptosis.

Intracellular Acidosis Promotes Mitochondrial Apoptosis Pathway: Role of EMMPRIN Down-regulation via Specific Single-chain Fv Intrabody

Extracellular matrix metalloproteinase inducer (EMMPRIN) is a human leukocyte surface molecule that is enriched on the surface of many cancer cells, and it plays an important role in proliferation and metastasis. In this study, we utilized the chimeric adenoviral vector Ad5/F35 carrying gene encoding scFv against EMMPRIN (scFv-M6-1B9) to down-regulate EMMPRIN cell surface expression and investigated programmed cell death response in colorectal cancer (CRC) cell, Caco-2. The scFv-M6-1B9 intrabody exhibits robust activity in reducing EMMPRIN cell surface expression. This approach led to the inducing of apoptosis, which was relative to the increasing of apoptotic bodies in sub-G1 peak, phosphatidylserine externalization, as well as TUNEL-positive cells. In addition, real-time RT-PCR and western blotting analysis indicated that apoptosis was enhanced through the mitochondrial pathway, a marked reduction of Bcl-2, leading to the translocation of cytochrome c and also the dramatic activation of caspase-3. Moreover, carcinoembryonic antigen (CEA), a tumor marker for CRC, was found to have significantly diminished in both secreted protein and mRNA levels. In conclusion, these findings suggest that EMMPRIN down-regulation by scFv-M6-1B9 intrabody has great potential in enhancing the efficacy of apoptosis induction through the mitochondrial pathway and in effecting a decline in the CEA level. Thus, its benefits could be applied to project the future prospects for targeted gene therapy and therapeutic application in monitoring colorectal cancer.

A unique nonsurgical management of internal hemorrhoids by Jīmūtaka Lepa

This is the era of fast foods. Irregularity in food timing, improper diet, and mental stress coupled with a sedentary life disturb the digestive system resulting in increased incidence of hemorrhoids. In the present report, we present two cases of intero-external hemorrhoids. Case 1: A 30-year old young male approached with intero-external hemorrhoid at 11 O’clock position as a primary. Case 2: A 41-year-old female visited with second degree intero-external hemorrhoid at 11 O’clock position. Hemorrhoids present in these patients can be considered as Kaphaja Arṣa. These cases were diagnosed by per rectal digital and proctoscopic examinations by ayurvedic proctologists. In both cases, application of Jīmūtaka Lepa was done under local anesthesia administered using lignocaine 2% with adrenaline. This was followed by manual anal dilatation. Jīmūtaka Lepa was applied to the internal hemorrhoids (Arṣa). Changes were observed in the form of edema, ulcer in 3-4 days and sloughing out of the pile mass up to 5-7 days. Subsequently fibrosis of hemorrhoidal masses started after 7 days. Jīmūtaka Lepa shows a significant effect in obliterating the hemorrhoidal mass within a month of application. The patients were followed-up regularly with proctoscopic examination in each visit and did not reveal any evidence of recurrence of the hemorrhoids.

DNA fragmentation and cell cycle arrest: a hallmark of apoptosis induced by Ruta graveolens in human colon cancer cells

In the present study, we investigated the anti-cancer effect of various potencies of Ruta graveolens (Ruta) on COLO-205 cell line, as evidenced by cytotoxicity, migration, clonogenecity, morphological and biochemical changes and modification in the levels of genes associated with apoptosis and cell cycle. On treatment of COLO-205 cells maximal effects were seen with mother tincture (MT) and 30C potencies, wherein decrease in cell viability along with reduced clonogenecity and migration capabilities were noted. In addition morphological and biochemical alterations such as nuclear changes (fragmented nuclei with condensed chromatin) and DNA ladder-like pattern (increased amount of fragmented DNA) in COLO-205 cells indicating apoptotic related cell death were seen. The expression of apoptosis and cell-cycle related regulatory genes assessed by reverse transcriptase-PCR revealed an up-regulation of caspase 9, caspase-3, Bax, p21 and p27 expression and down-regulation of Bcl-2 expression in treated cells. The mode of cell death was suggestive of intrinsic apoptotic pathway along with cell cycle arrest at the G2/M of the cell cycle. Our findings indicate that phytochemicals present in Ruta showed potential for natural therapeutic product development for colon carcinoma.

Achyranthes aspera root extracts induce human colon cancer cell (COLO-205) death by triggering the mitochondrial apoptosis pathway and S phase cell cycle arrest

Achyranthes aspera (AA) has been used traditionally for the cure of various disorders. However, the action of root extracts of AA as anticancer agent and its cellular mechanism remain unclear. The aim was to screen the antitumor effect of ethanolic (EAA) and aqueous (AAA) root extracts on the growth of colon cancer COLO-205 cells by testing their cytotoxicity, followed by their effect on clonogenicity, migration, and induction of apoptosis. Mechanisms leading to apoptosis and cell cycle arrest were also investigated by expression studies of caspase-9, caspase-3, Bax, Bcl-2, p16, p21, and p27 genes, followed by flow cytometric analysis for cell cycle distribution. Cytotoxicity screening of AA extracts indicated greater cytotoxic activity of AAA extract against COLO-205 cells. A series of events marked by apoptosis revealed loss of cell viability, chromatin condensation, and DNA fragmentation in AAA treated cells to a greater extent. The mRNA expression levels of caspase-9, caspase-3, Bax, p16, p21, and p27 were markedly increased in the AAA treated cells, along with decreased Bcl-2 expression. The cell cycle arrest at S phase was detected by flow cytometric analysis after treatment with AAA. Overall the study signifies the aqueous extracts as a promising therapeutic candidate against cancer.

Apoptogenic activity of ethyl acetate extract of leaves of Memecylon edule on human gastric carcinoma cells via mitochondrial dependent pathway

OBJECTIVE

To evaluate the anti-proliferative and apoptogenic activity of ethyl acetate extract from the leaves of Memecylon edule (EtAc-LME) in MKN-74, NUGC gastric cancer cells and non cancerous gastric mucous cells (GES-1), and to explore the mechanism of EtAc-LME induced apoptosis.

METHODS

The mechanism of EtAc-LME induced apoptosis was explored by analysing the activation of pro-caspases, PARP cleavage, expression of cytochrome-c (Cyt-c) was determined by western blotting, mRNA expression of Bcl-2, Bax by RT-PCR, loss of mitochondrial potential using DiOC6 dye, annexin binding assay and its influence on cell cycle arrest by flow cytometry.

RESULTS

The results indicated that EtAc-LME inhibited the gastric cancer cell growth in dose-dependent manner and cytotoxicity was more towards the gastric cancer cells (NUGC and MKN-74) compared to normal gastric cells (GES-1), suggesting more specific cytotoxicity to the malignant cells. Over expression of Cyt-c and subsequent activation of caspases-3 and down regulation of Bcl-2 and loss in mitochondrial potential in EtAc-LME treated MKN-74 and NUGC cells suggested that EtAc-LME induced apoptosis by mitochondrial dependent pathway.

CONCLUSIONS

The present findings suggest that ethyl acetate extract of Memecylon edule induces apoptosis selectively in gastric cancer cells emphasizing the importance of this traditional medicine for its potential in the treatment of gastric cancer.

Apoptosis induction by 13-acetoxyrolandrolide through the mitochondrial intrinsic pathway

The aim of this study was to evaluate the mechanisms of cytotoxicity of the sesquiterpene lactone 13-acetoxyrolandrolide, a nuclear factor kappa B (NF-κB) inhibitor that was previously isolated from Rolandra fruticosa. The effects associated with the inhibition of the NF-κB pathway included dose-dependent inhibition of the NF-κB subunit p65 (RelA) and inhibition of upstream mediators IKKβ and oncogenic Kirsten rat sarcoma (K-Ras). The inhibitory concentration of 13-acetoxyrolandrolide on K-Ras was 7.7 µM. The downstream effects of the inhibition of NF-κB activation were also investigated in vitro. After 24 h of treatment with 13-acetoxyrolandrolide, the mitochondrial transmembrane potential was depolarized in human colon cancer (HT-29) cells. The mitochondrial oxidative phosphorylation was also negatively affected, and reduced levels of nicotinamine adenine dinucleotide phosphate (NAD(P)H) were detected after 2 h of 13-acetoxyrolandrolide exposure. Furthermore, the expression of the pro-apoptotic protein caspase-3 increased in a concentration-dependent manner. Cell flow cytometry showed that 13-acetoxyrolandrolide induced cell cycle arrest at G1 , indicating that the treated cells had undergone caspase-3-mediated apoptosis, indicating negative effects on cancer cell proliferation. These results suggest that 13-acetoxyrolandrolide inhibits NF-κB and K-Ras and promotes cell death mediated through the mitochondrial apoptotic pathway.

Antiproliferation and induction of apoptosis in Ca9-22 oral cancer cells by ethanolic extract of Gracilaria tenuistipitata

The water extract of Gracilaria tenuistipitata have been found to be protective against oxidative stress-induced cellular DNA damage, but the biological function of the ethanolic extracts of G. tenuistipitata (EEGT) is still unknown. In this study, the effect of EEGT on oral squamous cell cancer (OSCC) Ca9-22 cell line was examined in terms of the cell proliferation and oxidative stress responses. The cell viability of EEGT-treated OSCC cells was significantly reduced in a dose-response manner (p < 0.0001). The annexin V intensity and pan-caspase activity of EEGT-treated OSCC cells were significantly increased in a dose-response manner (p < 0.05 to 0.0001). EEGT significantly increased the reactive oxygen species (ROS) level (p < 0.0001) and decreased the glutathione (GSH) level (p < 0.01) in a dose-response manner. The mitochondrial membrane potential (MMP) of EEGT-treated OSCC cells was significantly decreased in a dose-response manner (p < 0.005). In conclusion, we have demonstrated that EEGT induced the growth inhibition and apoptosis of OSCC cells, which was accompanied by ROS increase, GSH depletion, caspase activation, and mitochondrial depolarization. Therefore, EEGT may have potent antitumor effect against oral cancer cells.