Apoptosis as a novel target for cancer chemoprevention

Insights into Nimbolide molecular crosstalk and its anticancer properties

Nimbolide, one of the main ingredients constituent of Azadirachta indica (neem) leaf extract, has garnered attention for its potential as an anticancer agent. Its efficacy against various cancers and chemopreventive action has been demonstrated through numerous in vivo and in vitro studies. This updated review aims to comprehensively explore the chemopreventive and anticancer properties of nimbolide, emphasizing its molecular mechanisms of action and potential therapeutic applications in oncology. The review synthesizes evidence from various studies that examine nimbolide's roles in apoptosis induction, anti-proliferation, cell death, metastasis inhibition, angiogenesis suppression, and modulation of carcinogen-metabolizing enzymes. Nimbolide exhibits multifaceted anticancer activities, including the modulation of multiple cell signaling pathways related to inflammation, invasion, survival, growth, metastasis, and angiogenesis. However, its pharmacological development is still in the early stages, mainly due to limited pharmacokinetic and comprehensive long-term toxicological studies. Nimbolide shows promising anticancer and chemopreventive properties, but there is need for systematic preclinical pharmacokinetic and toxicological research. Such studies are essential for establishing safe dosage ranges for first-in-human clinical trials and further advancing nimbolide's development as a therapeutic agent against various cancers. The review highlights the potential of nimbolide in cancer treatment and underscores the importance of rigorous preclinical evaluation to realize its full therapeutic potential.

Analysis of the Anticancer Mechanism of OR3 Pigment from Streptomyces coelicolor JUACT03 Against the Human Hepatoma Cell Line Using a Proteomic Approach

This study assessed OR3 pigment, derived from Streptomyces coelicolor JUACT03, for its anticancer potential on HepG2 liver cancer cells and its safety on HEK293 normal cells. OR3 induced apoptosis and inhibited HepG2 cell proliferation, confirmed by caspase activation, Sub-G1 phase cell cycle arrest, and reduced colony formation. Proteomic analysis revealed altered expression of proteins associated with ribosomal function, mRNA processing, nuclear transport, proteasome activity, carbohydrate metabolism, chaperone function, histone regulation, and vesicle-mediated transport. Downregulation of proteins in MAPKAP kinase1, EIF2, mTOR, and EIF4 pathways contributed to apoptosis and cell cycle arrest. Changes in c-MYC, FUBP1 target proteins and upregulation of Prohibitin-1 (PHB1) were also noted. Western blot analysis supported alterations in eIF2, mTOR, and RAN pathways, including downregulation of RAB 5, c-MYC, p38, MAPK1, and MAPK3. OR3 exhibited significant anti-angiogenic activity in the in ovo CAM assay. In summary, OR3 demonstrated strong anticancer effects, inducing apoptosis, hindering proliferation, and displaying antiangiogenic properties. These findings highlight OR3's potential as an anticancer drug candidate, warranting further in vivo exploration.

Exploring the apoptotic effects of sericin on HCT116 cells through comprehensive nanostring transcriptomics and proteomics analysis

Sericin, a silk protein from Bombyx mori (silkworms), has many applications, including cosmetics, anti-inflammation, and anti-cancer. Sericin complexes with nanoparticles have shown promise for breast cancer cell lines. Apoptosis, a programmed cell death mechanism, stops cancer cell growth. This study found that Sericin urea extract significantly affected HCT116 cell viability (IC50 = 42.00 ± 0.002 µg/mL) and caused apoptosis in over 80% of treated cells. S-FTIR analysis showed significant changes in Sericin-treated cells' macromolecule composition, particularly in the lipid and nucleic acid areas, indicating major cellular modifications. A transcriptomics study found upregulation of the apoptotic signaling genes FASLG, TNFSF10, CASP3, CASP7, CASP8, and CASP10. Early apoptotic proteins also showed that BAD, AKT, CASP9, p53, and CASP8 were significantly upregulated. A proteomics study illuminated Sericin-treated cells' altered protein patterns. Our results show that Sericin activated the extrinsic apoptosis pathway via the caspase cascade (CASP8/10 and CASP3/7) and the death receptor pathway, involving TNFSF10 or FASLG, in HCT116 cells. Upregulation of p53 increases CASP8, which activates CASP3 and causes HCT116 cell death. This multi-omics study illuminates the molecular mechanisms of Sericin-induced apoptosis, sheds light on its potential cancer treatment applications, and helps us understand the complex relationship between silk-derived proteins and cellular processes.

Synergistic inhibitory actions of resveratrol, epigallocatechin-3-gallate, and diallyl trisulfide against skin cancer cell line A431 through mitochondrial caspase dependent pathway: a combinational drug approach

The harmful effect of chemotherapeutic side effects has paid a way to discover a novel with curative way for skin cancer treatment. Skin cancer prevention is more viable with the use of combination of bioactive agents than using of single bioactive compounds. Present work was demonstrated to evaluate the interaction of Resveratrol (Res), Epigallocatechin-3-gallate (EGCG), and diallyl trisulfide (DATS) with each other as a binary combination on A431 cells. Nuclear fragmentation analysis of combination of bioactive agents using DAPI analysis, detection of apoptosis, analysis of cell cycle, ROS assay, antimigration assays, and western blotting were implemented to study the combination of bioactive compounds on A431 cell line. Among the selected combination EGCG + DATS had a synergetic effect reducing cellular migration, increased intercellular reactive oxygen species generation, condensation, cell phagocytosis induced by phosphatidylserine externalization, rise in sub-G1 DNA content, and S-phase were cell cycle arrest. The combinations EGCG + DATS induced apoptotic proteins in A431 cells by upregulation of proapoptotic Bax and Bad proteins, a downmodulation of anti-apoptotic proteins Bcl2 and caspases (caspase-3, and -9) activity got triggered by intrinsic pathway. The combination of EGCG + DATS showed good anticancer potential against A431 skin cancer cell line via the mitochondrial caspase dependent pathway with very strong synergism. This finding will help to produce a novel combination/chemoprevention using dietary bioactive agents (EGCG + DATS) for the treatment of skin cancer after clinical trial.

Identifying synergistic combinations of Doxorubicin-Loaded polyquercetin nanoparticles and natural Products: Implications for breast cancer therapy

Combining chemotherapeutic agents with bioactive natural products is an attractive cancer treatment modality to reduce the dose and side effects of chemotherapy. Combination treatments with drugs having different mechanisms of action can also be beneficial in combatting the development of drug resistance by cancer cells. Nanoparticle (NP)-mediated drug delivery can further improve the therapeutic index of cytotoxic agents by enabling passive and/or active targeting to tumor tissues in vivo. Using doxorubicin (DOX) as a model chemotherapeutic agent, we developed three NP formulations based on polyquercetin (pQCT), an emerging nanocarrier platform. The NPs were co-assembled with DOX, pQCT, and either Pluronic P123, methoxy poly(ethylene glycol)-amine, or D-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS). Physicochemical characterization of the NPs revealed them to have a spherical morphology with high monodispersity, excellent drug loading capacity, and sustained drug release. Then, the NPs were evaluated in vitro to determine their potential synergism when combined with the bioactive natural products curcumin (CUR), tannic acid (TA), and thymoquinone (TQ) against breast cancer cells (MCF-7 and MDA-MB-231). Surprisingly, most of the combinations were found to be antagonistic. However, combinations containing CUR exhibited greater pro-apoptotic effects compared to the single agents, with polymer-modified pQCT NPs presenting as a promising nanoplatform for enhancing DOX's ability to promote cancer cell apoptosis. Our findings provide insights into the potential application of pQCT in nanomedicine, as well as the use of bioactive natural products in combination with DOX as a free agent and as an NP formulation in the treatment of breast cancer.

Potential Chemopreventive Role of Pterostilbene in Its Modulation of the Apoptosis Pathway

Cancer incidence keeps increasing every year around the world and is one of the leading causes of death worldwide. Cancer has imposed a major burden on the human population, including the deterioration of physical and mental health as well as economic or financial loss among cancer patients. Conventional cancer treatments including chemotherapy, surgery, and radiotherapy have improved the mortality rate. However, conventional treatments have many challenges; for example, drug resistance, side effects, and cancer recurrence. Chemoprevention is one of the promising interventions to reduce the burden of cancer together with cancer treatments and early detection. Pterostilbene is a natural chemopreventive compound with various pharmacological properties such as anti-oxidant, anti-proliferative, and anti-inflammatory properties. Moreover, pterostilbene, due to its potential chemopreventive effect on inducing apoptosis in eliminating the mutated cells or preventing the progression of premalignant cells to cancerous cells, should be explored as a chemopreventive agent. Hence, in the review, we discuss the role of pterostilbene as a chemopreventive agent against various types of cancer via its modulation of the apoptosis pathway at the molecular levels.

Only one carbon difference determines the pro-apoptotic activity of α-tocopheryl esters

α-Tocopheryl succinate (TS), a redox-silent succinyl ester of natural α-Tocopherol, has emerged as a novel anti-cancer agent. However, the underlying mechanism is unclear. We found that the terminal dicarboxylic moiety of tocopheryl esters contributes to apoptosis induction and thus cytotoxicity. To further examine this relationship, we compared the pro-apoptotic activity of TS, which has four carbon atoms in the terminal dicarboxylic moiety, to that of a newly synthesized, tocopheryl glutarate (Tglu), which has five. Cytotoxicity assays in vitro confirmed that TS stimulated apoptosis, while Tglu was non-cytotoxic. In investigating biological mechanisms leading to these opposing effects, we found that TS caused an elevation of intracellular superoxide, but Tglu did not. TS increased intracellular Ca²⁺ in cultured cells, suggesting induction of endoplasmic reticulum (ER) stress; however, Tglu did not affect Ca²⁺ homeostasis. 1,4,5-trisphosphate (IP₃ ) receptor antagonist 2-Aminoethyl diphenylborinate (2-APB) decreased TS-induced intracellular Ca²⁺ , restored mitochondrial activity and cell viability in TS-treated cells, establishing the ER-mitochondria relationship in apoptosis induction. Moreover, real-time PCR, immunostaining and Western blotting assays revealed that TS downregulated glucose-regulated protein 78 (GRP78), which maintains ER homeostasis and promotes cell survival. Conversely, Tglu upregulates GRP78. Taken together, our results suggest a model in which TS-mediated superoxide production and GRP78 inhibition induce ER stress, which elevates intracellular Ca²⁺ and depolarizes mitochondria, leading to apoptosis. Because Tglu does not affect superoxide generation and increases GRP78 expression, it inhibits ER stress and is thereby non-cytotoxic. Our research provides insight into the structure-activity relationship of tocopheryl esters regarding the induction of apoptosis.

Drug-herb combination therapy in cancer management

Cancer is the second leading cause of fatality all over the world. Various unwanted side effects are being reported with the use of conventional chemotherapy. The plant derived bioactive compounds are the prominent alternative medicinal approach for reduction of chemotherapy associated side effects. The data is collected from Pubmed, Sci-hub, Google scholar, and Research gate were systematically searched up to year 2020. Several herbal drugs have been investigated and found with grateful anti-cancer potentials hence, it can be used in combination with chemotherapy for the depletion of associated side-effects. Herbal drugs and their extracts contain a mixture of active ingredients, which show interactions within themselves and along with chemotherapeutic agents to show either synergistic or antagonistic therapeutic effects. Therefore, it is necessary to develop alternative treatment to control chemotherapy associated side-effects. In this review, we discussed some of the significant chemical compounds, which could be efficient against cancer. This review focuses on the different herbal drugs that play an important role in the treatment of cancer and its associated side-effects. This study aimed to evaluate the efficacy of herbal treatment in combination with chemotherapy for cancer treatment.

Herbal Ingredients in the Prevention of Breast Cancer: Comprehensive Review of Potential Molecular Targets and Role of Natural Products

Among various cancers, breast cancer is the most prevalent type in women throughout the world. Breast cancer treatment is challenging due to complex nature of the etiology of disease. Cell division cycle alterations are often encountered in a variety of cancer types including breast cancer. Common treatments include chemotherapy, surgery, radiotherapy, and hormonal therapy; however, adverse effects and multidrug resistance lead to complications and noncompliance. Accordingly, there is an increasing demand for natural products from medicinal plants and foods. This review summarizes molecular mechanisms of signaling pathways in breast cancer and identifies mechanisms by which natural compounds may exert their efficacy in the treatment of breast cancer.

Overcoming acquired resistance to third-generation EGFR inhibitors by targeting activation of intrinsic apoptotic pathway through Mcl-1 inhibition, Bax activation, or both

Treatment of EGFR-mutant non-small cell lung cancer (NSCLC) with mutation-selective third-generation EGFR-tyrosine kinase inhibitors (EGFR-TKIs) such as osimertinib has achieved remarkable success in the clinic. However, the immediate challenge is the emergence of acquired resistance, limiting the long-term remission of patients. This study suggests a novel strategy to overcome acquired resistance to osimertinib and other third-generation EGFR-TKIs through directly targeting the intrinsic apoptotic pathway. We found that osimertinib, when combined with Mcl-1 inhibition or Bax activation, synergistically decreased the survival of different osimertinib-resistant cell lines, enhanced the induction of intrinsic apoptosis, and inhibited the growth of osimertinib-resistant tumor in vivo. Interestingly, the triple-combination of osimertinib with Mcl-1 inhibition and Bax activation exhibited the most potent activity in decreasing the survival and inducing apoptosis of osimertinib-resistant cells and in suppressing the growth of osimertinib-resistant tumors. These effects were associated with increased activation of the intrinsic apoptotic pathway evidenced by augmented mitochondrial cytochrome C and Smac release. Hence, this study convincingly demonstrates a novel strategy for overcoming acquired resistance to osimertinib and other 3rd generation EGFR-TKIs by targeting activation of the intrinsic apoptotic pathway through Mcl-1 inhibition, Bax activation or both, warranting further clinical validation of this strategy.

Peiminine Induces G0/G1-Phase Arrest, Apoptosis, and Autophagy via the ROS/JNK Signaling Pathway in Human Osteosarcoma Cells in Vitro and in Vivo

Aims: Peiminine has been reported to have various pharmacological properties, including anticancer activity. In this study, we investigated the effect of this alkaloid on osteosarcoma and explored the underlying mechanisms.

Methods: To evaluate the antiosteosarcoma effects of peiminine in vitro, cell viability was assessed by CCK-8 and live/dead assays; the effects of the drug on apoptosis and the cell cycle were examined by flow cytometry; the effects on cell migration and invasion were detected by wound healing and Transwell assays, respectively, while its effects on autophagy were observed by transmission electron microscopy and an LC3 fluorescent puncta formation assay. The role of autophagy in the peiminine-mediated effects in osteosarcoma cells was evaluated by CCK-8 assay and western blotting after the application of the autophagy inhibitor chloroquine. The effect of peiminine on reactive oxygen species (ROS) production was analyzed using fluorescence confocal microscopy and spectrophotometry. Additionally, peiminine-treated osteosarcoma cells were exposed to SP600125, a JNK inhibitor, and N-acetylcysteine, a ROS scavenger, after which the contribution of the ROS/JNK signaling pathway to osteosarcoma was assessed using cell viability and LC3 fluorescent puncta formation assays, flow cytometry, and western blotting. A xenograft mouse model of osteosarcoma was generated to determine the antitumor effects of peiminine in vivo.

Results: Peiminine suppressed proliferation and metastasis and induced cell cycle arrest, apoptosis, and autophagy in osteosarcoma cells. These anticancer effects of peiminine were found to be dependent on intracellular ROS generation and activation of the JNK pathway. In line with these results, peiminine significantly inhibited xenograft tumor growth in vivo.

Conclusions: Peiminine induced G0/G1-phase arrest, apoptosis, and autophagy in human osteosarcoma cells via the ROS/JNK signaling pathway both in vitro and in vivo. Our study may provide an experimental basis for the evaluation of peiminine as an alternative drug for the treatment of osteosarcoma.

Insight into OroxylinA-7-O-β-d-Glucuronide-Enriched Oroxylum indicum Bark Extract in Oral Cancer HSC-3 Cell Apoptotic Mechanism: Role of Mitochondrial Microenvironment

Oroxylum indicum, of the Bignoniaceae family, has various ethnomedical uses such as an astringent, anti-inflammatory, anti-bronchitis, anti-helminthic and anti-microbial, including anticancer properties. The druggability of OI stem bark extract was determined by its molecular docking interactions with PARP and Caspase-3, two proteins involved in cell survival and death. Note that 50 µg/mL of Oroxylum indicum extract (OIE) showed a significant (p < 0.05%) toxicity to HSC-3 cells. MTT aided cell viability and proliferation assay demonstrated that 50 µg/mL of OIE displayed significant (p < 0.5%) reduction in cell number at 4 h of incubation time. Cell elongation and spindle formation was noticed when HSC-3 cells were treated with 50 µg/mL of OIE. OIE initiated DNA breakage and apoptosis in HSC-3 cells, as evident from DNA ladder assay and calcein/EB staining. Apoptosis potential of OIE is confirmed by flow cytometer and triple-staining (live cell/apoptosis/necrosis) assay. Caspase-3/7 fluorescence quenching (LANCE) assay demonstrated that 50 µg/mL of OIE significantly enhanced the RFU of caspases-3/7, indicating that the apoptosis potential of OIE is probably through the activation of caspases. Immuno-cytochemistry of HSC-3 cells treated with 50 µg/mL of OIE showed a significant reduction in mitochondrial bodies as well as a reduction in RFU in 60 min of incubation time. Immunoblotting studies clearly showed that treatment of HSC-3 cells with OI extract caused caspase-3 activation and PARP deactivation, resulting in apoptotic cell death. Overall, our data indicate that OIE is an effective apoptotic agent for human squamous carcinoma cells and it could be a future cancer chemotherapeutic target.

Phytochemical analysis and anticancer activity of Falcaria vulgaris Bernh growing in Moghan plain, northwest of Iran

Background

Falcaria vulgaris Bernh among the most important member of Apiaceae family has been used for medical investigation in Iran and some regions in the world. This plant possesses a range of coumarin and flavonoids compounds that have many therapeutic properties such as gastrointestinal and liver diseases, skin ulcers, gastric ulcers, and intestinal inflammation. It has also been found that these compounds lead to cytotoxic effects.

Objective

This study contains concentrates on the cytotoxic effect and induction of apoptosis on cancerous cells (SW-872) through various extracts and essential oil of Falcaria vulgaris Bernh. It considers the volatile compounds of effective samples.

Methods

The shoot of the plant was extracted by the Soxhlet apparatus and its essential oil was taken by the Clevenger apparatus. The cytotoxicity of the samples was evaluated by the MTT method and the mechanism of cancer cell death by flow cytometry and finally, the volatile compounds of essential oils and effective extracts were identified by GC-MS.

Results

The results demonstrated that n-Hexane extract and 40% VLC fraction had the greatest cytotoxic effect on SW-872 cells. While, the most abundant volatile compounds in essential oil and 40% VLC fraction of n-Hexane extract were terpenoid compounds like (+) spathulenol and caryophyllene oxide, in n-Hexane extract tetradecan, and spathulenol were the most, respectively.

Conclusion

The fraction of 40% n-Hexane was in a concentration-dependent manner and significantly with controlling cells inhibited the growth of cancer cells. A plausible explanation could be made to account for this effect. This inhibition was made through induction of apoptosis and due to the presence of effective volatile compounds such as terpenoids and non-terpenoids which could be considered as valuable natural sources for the isolation of anti-cancer compounds.

TRK inhibitors block NFKB and induce NRF2 in TRK fusion-positive colon cancer

Tropomyosin receptor kinase (TRK) fusion is one of the oncogenic driver causes of colon cancer, and tropomyosin 3-neurotrophic receptor tyrosine kinase 1 (TPM3-NTRK1) fusion has been detected in the KM12SM cell line. In the present study, we investigated anticancer mechanisms in the KM12SM cell line using three different form of dovitinib (dovitinib (free base), dovitinib lactate (mono acid), and dovitinib dilactic acid (diacid)) and four TRK inhibitors (LOXO-101, entrectinib, regorafenib, and crizotinib). Exposure of TRK inhibitors at concentrations of 10 nM resulted in the apoptosis of KM12SM cells, whereas regorafenib had no effect. Treatment with all inhibitors except regorafenib also significantly increased the expression levels of the genes nuclear factor-erythroid 2-related factor 2 (NRF2) and glutamyl cysteine ligase catalytic subunit (GCLC) in KM12SM. These drugs significantly reduced expression of the phosphorylated proteins NFκB and COX-2 in the KM12SM cell line, and significantly attenuated KM12SM cell migration, according to a Transwell migration assay. Together, these results suggest that TRK inhibitors block products of carcinogenesis by negatively regulating the NFκB signaling pathway and positively regulating the antioxidant NRF2 signaling pathway.

Marine-derived pipeline anticancer natural products: a review of their pharmacotherapeutic potential and molecular mechanisms

Background

Cancer is a complex and most widespread disease and its prevalence is increasing worldwide, more in countries that are witnessing urbanization and rapid industrialization changes. Although tremendous progress has been made, the interest in targeting cancer has grown rapidly every year. This review underscores the importance of preventive and therapeutic strategies.

Main text

Natural products (NPs) from various sources including plants have always played a crucial role in cancer treatment. In this growing list, numerous unique secondary metabolites from marine sources have added and gaining attention and became potential players in drug discovery and development for various biomedical applications. Many NPs found in nature that normally contain both pharmacological and biological activity employed in pharmaceutical industry predominantly in anticancer pharmaceuticals because of their enormous range of structure entities with unique functional groups that attract and inspire for the creation of several new drug leads through synthetic chemistry. Although terrestrial medicinal plants have been the focus for the development of NPs, however, in the last three decades, marine origins that include invertebrates, plants, algae, and bacteria have unearthed numerous novel pharmaceutical compounds, generally referred as marine NPs and are evolving continuously as discipline in the molecular targeted drug discovery with the inclusion of advanced screening tools which revolutionized and became the component of antitumor modern research.

Conclusions

This comprehensive review summarizes some important and interesting pipeline marine NPs such as Salinosporamide A, Dolastatin derivatives, Aplidine/plitidepsin (Aplidin®) and Coibamide A, their anticancer properties and describes their mechanisms of action (MoA) with their efficacy and clinical potential as they have attracted interest for potential use in the treatment of various types of cancers.

Anticancer, anti-proliferative activity of Avicennia marina plant extracts

Purpose

Medical halophytes plants are potent sources of bioactive secondary metabolite components used against different diseases. Avicenniamarina one of the typical halophytes plant species used in folk medicine to treat smallpox, rheumatism, and ulcer. Despite the richness of A.marina with polyphenolic, flavonoids, terpenoid, and terpene, contents remain poorly investigated against cancer types. Consequently, to explore the function-composition relationship of A.marina hexane leaves crude extract, the current study designed to investigate the cytotoxicity, apoptotic and antiproliferative impacts on the colon (HCT-116), liver (HepG2), and breast (MCF-7) cancer cell lines.

Materials and Methods

Therefore, the cytotoxicity impact screening carried out by Sulforhodamine-B assay. While, the initiation of the apoptosis evaluated by chromatin condensing, early apoptosis, late apoptosis and the formation and appearance of apoptotic bodies. On the other hand, the flow cytometry used to identify the phase of inhibition where the determined IC₅₀ value used. While, the chemical composition of the hexane extract was detected using liquid chromatography-mass spectrometry/mass spectrometry.

Results

Revealed that hexane extract showed a weak induction of apoptosis despite the formation of apoptotic bodies and the high cell inhibitory effect on all tested cell lines with IC₅₀ values (23.7 ± 0.7, 44.9 ± 0.93, 79.55 ± 0.57) μg/ml on HCT-116, HepG2, and MCF-7, respectively. Furthermore, it showed the ability to inhibit cell cycle in G0/G1 for HCT-116, S phase for HepG2, and MCF-7.

Conclusion

In the light of these results, the current study suggests that A.marina leaves hexane extract may be considered as a candidate for further anticancer drug development investigations.

Momordica charantia L. induces non-apoptotic cell death in human MDA-MB-436 breast and A549 lung cancer cells by disrupting energy metabolism and exacerbating reactive oxygen species' generation

ETHNOPHARMACOLOGICAL RELEVANCE

Bitter melon, Momordica charantia L. (MC), is an ethnomedicinal plant cultivated in different climes. It's cytotoxic effect on several cancer cell lines has been evaluated. However, there have been contrasting reports on the actual mechanism (s) involved in the observed cell death induced by MC.

AIMS OF THE STUDY

To probe the mechanism of cell death induction in MDA-MB-436 (Breast) and A549 (lung) cancer cell lines treated with fractions (ethyl acetate, dichloromethane and hexane) derived from the aqueous extract of MC.

MATERIALS AND METHODS

Aqeous extract of the leaves of MC were fractionated using solvents of different polarities (ethyl acetate (D3), n-hexane (D4), dichloromethane (D5)). The cells were incubated with 100 and 125 μg/mL of the fractions 24 hours. Combination of fluorescence microscopy, enzyme assays, Western blot analyses and flow cytometry were employed in the study.

RESULTS

Treatment of the cells with MC fractions reduced Mitochondrial Membrane Potential (MMP) and intracellular ATP levels, while increasing reactive oxygen species levels without classical biochemical and morphological apoptotic features were seen. However, the fractions failed in upregulating either caspase-3 activation or cytochrome c release in the cancer cells.

CONCLUSION

Overall, these results suggest that the cytotoxic effect of MC on the selected cancer cells is mediated by loss of mitochondrial function via loss of respiration leading to cell death rather than by the classical release of cytochrome c or caspase-3 activated apoptosis.

Fractions of Ageratum conyzoides L. (Compositae) induce mitochondrial-mediated apoptosis in rats: Possible option in monosodium glutamate-induced hepatic and uterine pathological disorder

ETHNOPHARMACOLOGICAL RELEVANCE

Several pathological disorders have been attributed to either oxidative stress or defect in apoptotic signaling pathway. Some bioactive compounds elicit their antiproliferative properties by induction of apoptosis via mitochondrial permeability transition (mPT) pore opening.

AIM OF STUDY

The present study therefore investigated the effects of various fractions of methanol extract of Ageratum conyzoides L. (MEAC) on mitochondrial-mediated apoptosis and the possible protective potential of the most potent against monosodium glutamate (MSG)-induced hepatic damage and uterine pathological disorder. The plant is folklorically used in the treatment of cancer and gynecological disorder.

MATERIALS AND METHODS

The MEAC was partitioned in succession and concentrated at 40 °C to obtain chloroform(CFAC), ethylacetate(EFAC) and methanol(MFAC) fractions. Mitochondria were isolated by differential centrifugation. The opening of mPT pore, mATPase activity and hepatic DNA fragmentation were assessed spectrophotometrically. Caspases 9 and 3, SOD and GSH-Px activities and MDA level were determined using ELISA technique. Histological assessment of the liver and uterine sections and GC-MS analysis of the most potent fraction were carried out.

RESULTS

The investigation showed that oral administration of the fractions caused induction of mPT pore opening, enhanced mATPase activity, upregulated the activities of caspases 9 and 3 and also, caused hepatic DNA fragmentation with CFAC being the most potent. The CFAC reversed severe MSG-induced hepatic damage and uterine hyperplasia. The MSG-induced oxidative stress was normalized by CFAC. The GC-MS analysis of CFAC revealed the presence of some pharmacologically relevant phytochemicals.

CONCLUSION

These findings therefore suggest that fractions of Ageratum conyzoides induce mitochondrial-mediated apoptosis. Moreover, CFAC, which is the most potent has a promising antioxidant and antiproliferative potential against MSG-induced hepatic and uterine pathological disorder.

A Nudibranch Marine Extract Selectively Chemosensitizes Colorectal Cancer Cells by Inducing ROS-Mediated Endoplasmic Reticulum Stress

The present study shows the putative antiproliferative mechanism of action of the previously analytically characterized nudibranch extract (Dolabella auricularia, NB) and its different effects in colon cancer cells vs. nontumor colon cells. NB extract increased the accumulation of reactive oxygen species (ROS) and increased endoplasmic reticulum (ER) stress via stimulation of the unfolded protein response. Stress scavengers, N-acetylcysteine (NAC) and 4-phenylbutyric acid (4-PBA), decreased the stress induced by NB. The results showed that NB extract increased ER stress through overproduction of ROS in superinvasive colon cancer cells, decreased their resistance threshold, and produced a nonreturn level of ER stress, causing DNA damage and cell cycle arrest, which prevented them from achieving hyperproliferative capacity and migrating to and invading other tissues. On the contrary, NB extract had a considerably lower effect on nontumor human colon cells, suggesting a selective effect related to stress balance homeostasis. In conclusion, our results confirm that the growth and malignancy of colon cancer cells can be decreased by marine compounds through the modification of one of the most potent resistance mechanisms present in tumor cells; this characteristic differentiates cancer cells from nontumor cells in terms of stress balance.

The metabolite 5-methyl-1,3-benzenediol and its derivative methyl-2,4-dihydroxy-6-methylbenzoate from the lichen Parmotrema tinctorum with potent apoptotic and anti-angiogenesis effects

Nature has been a rich resource of novel anticancer agents, one such source being lichens, which represent the symbiosis between algae and fungi with diverse range of secondary metabolites having therapeutic significance. With respect to this, the present study evaluates the in vitro apoptogenic profile of secondary metabolites from the lichen Parmotrema tinctorum towards cancer cell lines. Treatment with TLC-purified fraction 1 from P. tinctorum resulted in significant reduction in the cell viabilities of cancer cells with IC50 values ranging between 1.2 and 12.8 μg/ml. The potential anticancer effect of the bioactive fraction was further supported by Trypan blue cell viability, LDH and DNA fragmentation assays. At the cellular level, induction of apoptosis was confirmed through the activation of the caspase cascade and apoptotic cells accumulating in the Sub-G1 phase of cell cycle. Angiogenesis being one of the major characteristics needed for cancer growth, the ability of the lichen fraction to inhibit angiogenesis was checked through in ovo Yolk Sac Membrane (YSM) assay and was found to be significant. The study also verified the non-toxic nature of the bioactive fraction towards normal human peripheral lymphocytes. HPLC analysis and GC-MS characterisation of the bioactive fraction indicated the presence of 5-methyl-1,3-benzenediol and its derivative methyl-2,4-dihydroxy-6-methylbenzoate.

Psiadin and plectranthone selectively inhibit colorectal carcinoma cells proliferation via modulating cyclins signaling and apoptotic pathways

Three scarce terpenes, psiadin, plectranthone and saudinolide, were obtained after chromatographic isolation and purification from the aerial parts of the respective plants. Their identities were established based on their spectral data. Their anticancer effects against two human colorectal carcinoma cell lines, CCL233 and CCL235, along with the potential molecular mechanisms of action, were explored. Psiadin and plectranthone exhibited marked growth inhibition on both cell lines in a time- and dose-dependent manner with minimal cytotoxicity against normal breast cells (HB2). The terpenes even showed superior activities to the tested standards. Flow cytometry showed apoptosis induction and alteration in the cell cycle in colorectal cancer cells treated with both compounds. Nevertheless, it was also found that both compounds inhibited NF-κB transcriptional activity, induced mitochondrial membrane potential depolarization and increased the percentage of reactive oxygen species in the treated cancer cells in a dose-dependent manner as well. Since the anticancer effect of psiadin on cancer cells was higher than that produced by plectranthone, only psiadin was tested to determine its possible targets. The results suggested a high degree of specificity of action affecting particular cellular processes in both cancer cells. In conclusion, both terpenes, in particular psiadin, showed significant discriminative therapeutic potential between cancer and normal cells, a value that is missing in current chemotherapies.

Antiproliferative and antioxidant properties of nematocysts crude venom from jellyfish Acromitus flagellatus against human cancer cell lines

This study aimed to investigate the antiproliferative and antioxidant properties of crude venom from the nematocyst of Jellyfish Acromitus flagellates on human lung cancer (A549) and liver cancer (HepG2) cell lines. The prepared crude venom was subjected to analyses of the biochemical constituents, protein profiles, antioxidant and anticancer activities by standard methods. The extracted venom was pale-yellow in color and viscous/sticky. The biochemical composition such as, protein (1.547 mg/ml), lipid (0.039 mg/ml) and carbohydrate (0.028 mg/ml) was estimated. Protein profiles were determined by SDS PAGE, the result revealed that the molecular weight range from 205 - 3.5 kDa. The free radical scavenging activity was analyzed by the reducing potential (56.36%), DPPH (72.47%), hydroxyl (68.50%), superoxide anion (65.75%), and nitric oxide (33.04%). The cell viability was observed by using different concentrations (20 to 100 µg/ml) of crude venom on A549 and HepG2 cancer cell lines and the IC50 values were recorded in (60 μg/ml and 40 μg/ml) respectively, while it had none cytotoxic effects on Vero cell line up to the concentration of 90 μg/ml. These results suggest that crude venom from nematocyst of A. flagellatus possesses anti-cancer activity and able to develop novel drugs on marine-derived compounds.

Plant Natural Products: Promising Resources for Cancer Chemoprevention

Cancer is a major factor threatening human health and life safety, and there is a lack of safe and effective therapeutic drugs. Intervention and prevention in premalignant process are effective ways to reverse carcinogenesis and prevent cancer from occurring. Plant natural products are rich in sources and are a promising source for cancer chemoprevention. This article reviews the chemopreventive effects of natural products, especially focused on polyphenols, flavonoids, monoterpene and triterpenoids, sulfur compounds, and cellulose. Meanwhile, the main mechanisms include induction of apoptosis, antiproliferation and inhibition of metastasis are briefly summarized. In conclusion, this article provides evidence for natural products remaining a prominent source of cancer chemoprevention.

Thymoquinone: A Tie-Breaker in SARS-CoV2-Infected Cancer Patients?

Since the beginning of the SARS-CoV-2(severe acute respiratory syndrome-coronavirus-2) pandemic, arace to develop a vaccine has been initiated, considering the massive and rather significant economic and healthcare hits that this virus has caused. The pathophysiology occurring following COVID-19(coronavirus disease-2019) infection has givenhints regarding the supportive and symptomatic treatments to establish for patients, as no specific anti-SARS-CoV-2 is available yet. Patient symptoms vary greatly and range from mild symptoms to severe fatal complications. Supportive treatments include antipyretics, antiviral therapies, different combinations of broad-spectrum antibiotics, hydroxychloroquine and plasma transfusion. Unfortunately, cancer patients are at higher risk of viral infection and more likely to develop serious complications due to their immunocompromised state, the fact that they are already administering multiple medications, as well as combined comorbidity compared to the general population. It may seem impossible to find a drug that possesses both potent antiviral and anticancer effects specifically against COVID-19 infection and its complications and the existing malignancy, respectively. Thymoquinone (TQ) is the most pharmacologically active ingredient in Nigella sativa seeds (black seeds); it is reported to have anticancer, anti-inflammatory and antioxidant effects in various settings. In this review, we will discuss the multiple effects of TQ specifically against COVID-19, its beneficial effects against COVID-19 pathophysiology and multiple-organ complications, its use as an adjuvant for supportive COVID-19 therapy and cancer therapy, and finally, its anticancer effects.

Anti-Cancerous Effect of Rutin Against HPV-C33A Cervical Cancer Cells via G0/G1 Cell Cycle Arrest and Apoptotic Induction

BACKGROUND

Nowadays, the potential therapeutic role of various bioflavonoids including Curcumin, Luteolin and Resveratrol has currently been well-documented in a vast range of fatal complications including synaptic failure and cancers. These bioflavonoids are widely being implemented for the treatment of various cancers as they possess anti-cancerous, anti-oxidant and anti-inflammatory properties. Moreover, they are also used as a better alternative to conventional therapies since; these are non-toxic to cells and having no or least side effects. Notably, the pertinent therapeutic role of Rutin in cervical cancer is still unsettled however, its anti-cancerous role has already been reported in other cancers including prostate and colon cancer. Rutin (Vitamin P or Rutoside) is a polyphenolics flavonoid exhibiting multi-beneficial roles against several carcinomas.

OBJECTIVE

Despite the evidence for its several biological activities, the anticancer effects of Rutin on human cervical cancer (C33A) cells remain to be explored. In this study, the anticancer potential of Rutin was investigated by employing the key biomarkers such as nuclear condensation reactive oxygen species (ROS), apoptosis, and changes in mitochondrial membrane potential (MMP).

RESULTS

Our findings showed that Rutin treatment reduced the cell viability, induced significant increase in ROS production and nuclear condensation in dose-dependent manner. Moreover, Rutin provoked apoptosis by inducing decrease in MMP and activation of caspase-3. Cell cycle analysis further confirmed the efficacy of Rutin by showing cell cycle arrest at G0/G1 phase.

CONCLUSION

Thus, our study is envisaged to open up interests for elucidating Rutin as an anticancerous agent against cervical cancer.

Effects of low-to-moderate ethanol consumption on colonic growth and gene expression in young adult and middle-aged male rats

Excessive alcohol consumption is a risk factor associated with colorectal cancer; however, some epidemiological studies have reported that moderate alcohol consumption may not contribute additional risk or may provide a protective effect reducing colorectal cancer risk. Prior research highlights the importance of proliferation, differentiation, and apoptosis as parameters to consider when evaluating colonic cell growth and tumorigenesis. The present study investigated whether chronic low-to-moderate ethanol consumption altered these parameters of colonic cell growth and expression of related genes. Twenty-four nondeprived young adult (109 days old) and 24 nondeprived middle-aged (420 days old) Wistar rats were randomly assigned to an ethanol-exposed or a water control group (n = 12/group). The ethanol group was provided voluntary access to a 20% v/v ethanol solution on alternate days for 13 weeks. Colon tissues were collected for quantitative immunohistochemical analyses of cell proliferation, differentiation and apoptosis using Ki-67, goblet cell and TUNEL, respectively. Gene expression of cyclin D1 (Ccnd1), Cdk2, Cdk4, p21waf1/cip1 (Cdkn1a), E-cadherin (Cdh1) and p53 were determined by quantitative real-time polymerase chain reaction in colonic scraped mucosa. Ethanol treatment resulted in a lower cell proliferation index and proliferative zone, and lower Cdk2 expression in both age groups, as well as trends toward lower Ccnd1 and higher Cdkn1a expression. Cell differentiation was modestly but significantly reduced by ethanol treatment only in older animals. Overall, older rats showed decreases in apoptosis and gene expression of Cdk4, Cdh1, and p53 compared to younger rats, but there was no observed effect of ethanol exposure on these measures. These findings suggest that low-to-moderate ethanol consumption improves at least one notable parameter in colonic tumorigenesis (cell proliferation) and associated gene expression regardless of age, however, selectively decreased cell differentiation among older subjects.

Seseli petraeum M. Bieb. (Apiaceae) Significantly Inhibited Cellular Growth of A549 Lung Cancer Cells through G0/G1 Cell Cycle Arrest

Seseli L. is an important genus of the Apiaceae family, with a large number of aromatic species. It is used in traditional medicine extensively, but there is quite limited information on their phytochemicals and biological activities. Seseli petraeum M. Bieb. grows in Northern Anatolia, and there are no phytochemical studies on this species. In the present study, we aimed to investigate the effect of the extracts of S. petraeum on A549 lung cancer cell proliferation. For this purpose, the antiproliferative effect was determined via MTT assay, and the extracts obtained from the root of S. petraeum showed a significant inhibitory effect on cell proliferation. The hexane extract of the root exhibited potent inhibition on A549 cancer cell growth at the 24th hour with 3.432 mg/mL IC50 value. The results also showed that the hexane extract had displayed cytotoxic effect through an arrest at the G0/G1 phase of the cell cycle and induced apoptosis as well as DNA damage of A549 cells. Consequently, this study demonstrated the antiproliferative potential of the extracts from S. petraeum, especially hexane extract from the roots. Further studies are required to identify the mechanisms underlying these effects.

Anti-Proliferative Activity of A Hydrophilic Extract of Manna from Fraxinus angustifolia Vahl through Mitochondrial Pathway-Mediated Apoptosis and Cell Cycle Arrest in Human Colon Cancer Cells

Manna is produced from the spontaneous solidification of the sap of some Fraxinus species, and, owing its content in mannitol, is used in medicine as a mild laxative. Manna is also a rich source of characteristic bio-phenols with reducing, antioxidant and anti-inflammatory properties. This study assesses the activity of a hydrophilic extract of manna (HME) on cellular and molecular events in human colon-rectal cancer cells. HME showed a time- and concentration-dependent anti-proliferative activity, measured by MTT assay, in all the cell lines examined, namely Caco-2, HCT-116 and HT-29. The amounts of HME that caused 50% of cell death after a 24 h treatment were 8.51 ± 0.77, 10.73 ± 1.22 and 28.92 ± 1.99 mg manna equivalents/mL, respectively; no toxicity was observed in normally differentiated Caco-2 intestinal cells. Hydroxytyrosol, a component of HME known for its cytotoxic effects on colon cancer cells, was ineffective, at least at the concentration occurring in the extract. Through flow-cytometric techniques and Western blot analysis, we show that HME treatment causes apoptosis, assessed by phosphatidylserine exposure, as well as a loss of mitochondrial membrane potential, an intracellular formation of reactive oxygen species (ROS), increases in the levels of cleaved PARP-1, caspase 3 and Bax, and a decrease in Bcl-2 expression. Moreover, HME interferes with cell cycle progression, with a block at the G1/S transition. In conclusion, the phytocomplex extracted from manna exerts an anti-proliferative activity on human colon cancer cells through the activation of mitochondrial pathway-mediated apoptosis and cell cycle arrest. Our data may suggest that manna could have the potential to exert chemo-preventive effects for the intestine.

Dark Sweet Cherry (Prunus avium) Phenolics Enriched in Anthocyanins Induced Apoptosis in MDA-MB-453 Breast Cancer Cells through MAPK-Dependent Signaling and Reduced Invasion via Akt and PLCγ-1 Downregulation

Dark sweet cherries (DSCs) are rich source of phenolics known to exert anticancer and anti-invasive activities. This study elucidated the molecular mechanisms underlying the activity of DSC phenolics against MDA-MB-453 breast cancer cells In Vitro. Cells were treated with DSC phenolics in whole extract (WE), and fractions enriched in anthocyanins (ACN) and proanthocyanidins (PCN) at concentrations that inhibited cell growth by 50%. Results showed that DSC phenolics suppressed Akt and PLCγ-1 activation, and inhibited cell motility and invasion, but only ACN reached significance. The extrinsic and intrinsic apoptotic pathways were also activated by DSC phenolics via caspase-8 cleavage and increased Bax/Bcl-2 ratio, with ACN exhibiting significant activation and stronger PARP-1 cleavage. Furthermore, sustained activation of mitogen-activated protein kinases (MAPKs) ERK1/2 and p38 was observed wherein ERK1/2 (U0126) and p38 (SB203580) inhibitors confirmed crosstalk ERK1/2-Akt and MAPK intrinsic mitochondrial pathways. In conclusion, DSC phenolics inhibited MDA-MB-453 breast cancer cells by targeting cell signaling pathways that induce apoptosis and suppress cell invasion, with ACN showing enhanced chemopreventive activities.

Citronellol, an Acyclic Monoterpene Induces Mitochondrial-Mediated Apoptosis through Activation of Proapoptotic Factors in MCF-7 and MDA-MB-231 Human Mammary Tumor Cells

The present study investigated the anticancer activity of citronellol (CT) by analyzing the mitochondrial-mediated activation of apoptosis in MCF-7 and MDA-MB-231 human mammary tumor cell lines. Cytotoxicity, cell growth, and apoptosis were determined by measuring reactive oxygen species (ROS), the level of mitochondrial membrane potential (ΔΨm), DNA damage, and changes in morphology and expression of proteins involved in apoptosis in MCF-7 and MDA-MB-231 cells. Our results indicate that CT induces apoptosis as evidenced by the loss of cell viability, increase ROS generation, altered ΔΨm, and enhanced DNA damage. Further, CT inhibits Bcl-2 expression with the up-regulation of Bax, caspase-9, and -7 in both cancer cells. CT induces apoptosis in MCF-7 human mammary tumor cells by inducing oxidative damage and modulating the expression of various pro and anti-apoptotic proteins. Hence, CT might be a potential therapeutic agent for the treatment of breast cancer.

Centaurea bruguierana inhibits cell proliferation, causes cell cycle arrest, and induces apoptosis in human MCF-7 breast carcinoma cells

Centaurea bruguierana, of the Asteraceae family, has a long history of use in traditional medicines for the treatment of various ailments. However, the anticancer activity and underlying mechanisms have not yet been assessed. The C. bruguierana was extracted with methanol and fractionated into four different fractions. Different cancer cells and one non-cancerous were used to examine the cytotoxic effects of these fractions using MTT assay. The most potent fraction, C. bruguierana ethyl acetate fraction (CB EtOAc), was explored for its effects on cell cycle progression and apoptosis induction by Hoechst staining and annexin V-PI double staining in MCF-7 cells. The expression of apoptosis-related genes was quantified by RT-PCR. Of all fractions, CB EtOAc was found to have the strongest antiproliferative activity (IC₅₀ = 10 μg/mL) against MCF-7 cells. The antiproliferative activity of the CB EtOAc fraction against MCF-7 was correlated with arrested of cell cycle in the G1 phase, nuclear fragmentation, and the exposure of phosphatidylserine. The induction of apoptosis by CB EtOAc in MCF-7 cells was also associated with an increase in the Bax/Bcl-2 ratio and higher expression of caspases. Overall, our results demonstrated that CB EtOAc showed apoptosis-inducing effects, suggesting that C. bruguierana may be a promising source for a novel chemotherapeutic agents for the treatment of breast cancer.

Chemopreventive activity of hydroethanolic Murraya koenigii leaves extract (HEMKLE) against chemically induced skin carcinogenesis in mice

The present study aimed to examine the chemoprotective effect of Hydroethanolic Murraya koenigii leaves extract (HEMKLE) on murine skin carcinogenesis model. For the study, male LACA mice divided into four groups (n = 15 per group). Group I (Control), Group II (DMBA/TPA), Group III (HEMKLE), and Group IV (HEMKLE + DMBA/TPA). Skin tumors were induced in Group II (DMBA/TPA) and Group IV (HEMKLE + DMBA/TPA) by topical application of 7, 12 dimethylbenz[a]anthracene (DMBA) [500 nmol/100 μL of acetone, twice a week for two weeks] and 12-O-tetradecanoyl phorbol-13-acetate (TPA) [1.7 nmol/100 μL of acetone, twice a week for eighteen weeks] and HEMKLE (200 mg/kg b. w.) was administered orally (instilled by oral gavage). The chemoprotective response of HEMKLE was evident by inhibition in tumor incidence, mean tumor volume, mean tumor burden, total number of tumors, and tumor size in Group IV (HEMKLE + DMBA/TPA) when compared to Group II (DMBA/TPA). HEMKLE administration also decreased the reactive oxygen species (ROS) and lipid peroxidation (LPO) levels and increased the antioxidants enzyme activities in Group IV (HEMKLE + DMBA/TPA) when compared to Group II (DMBA/TPA) that suggests its antioxidant potential. HEMKLE administration also increased the mRNA and protein expression of caspase-9 and caspase-3 and decreased the mRNA and protein expression of Bcl-2 in Group IV (HEMKLE + DMBA/TPA) when compared to Group II (DMBA/TPA) that suggest its apoptosis-inducing effect on DMBA/TPA induced skin carcinogenesis.

Myricitrin from Combretum lanceolatum Exhibits Inhibitory Effect on DNA-Topoisomerase Type IIα and Protective Effect Against In Vivo Doxorubicin-Induced Mutagenicity

Flavonoids-compounds abundant in balanced daily diets-have been extensively investigated for biological activity. The pronounced antiproliferative effects of flavonoids have prompted studies to elucidate their mode of action against tumor cells. The anticancer properties of myricetin, a 3',4',5'-tri-hydroxylated flavonol, have been confirmed for a number of neoplasms, but myricitrin, its 3-O-rhamnoside derivative found in fruits and other parts of edible plants, has been scarcely investigated as a chemopreventive agent. This study evaluated the antiproliferative potential of myricitrin obtained from Combretum lanceolatum (Combretaceae) against MCF7 (breast), PC-3 (prostate), HT-29 (colon), 786-0 (kidney), and HL-60 (acute promyelocytic leukemia) cancer cell lines, using the sulforhodamine B and tetrazolium salt assays. Myricitrin proved most effective in inhibiting growth of HL-60 cells (GI₅₀ = 53.4 μmol·L^-1), yet showed weak antiproliferative activity against other cell lines. Possible cytotoxic mechanisms involving inhibition of topoisomerases I and IIα by myricitrin were also evaluated, revealing inhibitory activity only against topoisomerase IIα. The results suggested that topoisomerase IIα inhibition is the probable mechanism responsible for the antiproliferative activity of myricitrin. In vivo mutagenicity by myricitrin and its possible antimutagenic effect on doxorubicin-induced DNA damage were also investigated by performing the somatic mutation and recombination test (SMART) on Drosophila melanogaster. Myricitrin proved nonmutagenic to the offspring of standard (ST) and high-bioactivation (HB) crosses, while cotreatments with doxorubicin revealed the antimutagenic properties of myricitrin, even under conditions of high metabolic activation.

Long non-coding RNA PTCSC3 inhibits human oral cancer cell proliferation by inducing apoptosis and autophagy

INTRODUCTION

Long non-coding RNAs (lncRNAs) have gained increased attention due to the discovery of their roles in cancer-related processes. LncRNA PTCSC3 has been shown to have tumour-suppressive effects in thyroid cancer and glioblastoma. This study investigated the role of lncRNA PTSC3 in human oral cancer.

MATERIAL AND METHODS

Cell viability was determined by MTT assay. The induction of apoptosis was confirmed by 4',6-diamidino-2-phenylindole (DAPI) and Annexin V/PI assays. Ultrastructural analysis was performed by electron microscopy. Transwell assay was used to monitor the invasion of oral cancer cells.

RESULTS

The results revealed significant (p < 0.05) suppression of PTCSC3 expression in human oral cancer tissues and cell lines. The overexpression of PTCSC3 caused a significant (p < 0.05) decline in the proliferation of the human oral cancer cells via induction of apoptotic cell death which was accompanied by remarkable enhancement of Bax and suppression of Bcl-2. The electron microscopic analysis showed the development of autophagic vesicles in both the SCC-1 and SCC-9 cells indicative of autophagy. The western blotting analysis showed that PTCSC3 overexpression caused a remarkable increase in LC3B-I and Beclin 1 expression. PTCSC3 overexpression caused a significant (p < 0.05) decrease in invasion of the human SCC-1 and SCC-9 oral cancer cells. The invasion of the SCC-1 and SCC-9 cells was inhibited by 62% and 69% respectively.

CONCLUSIONS

Overall, the evidence suggests that lncRNA PTCSC3 acts as a tumour suppressor in human oral cancer and suppresses oral cancer proliferation via induction of apoptosis and autophagy.

Carvacrol Induced Program Cell Death and Cell Cycle Arrest in Androgen-Independent Human Prostate Cancer Cells via Inhibition of Notch Signaling

BACKGROUND

Several studies have revealed that abnormal activation of Notch signaling is closely related with the development and progression of prostate cancer. Although there are numerous therapeutic strategies, a more effective modality with least side effects is urgently required for the treatment of prostate cancer. Carvacrol is a monoterpenoid phenol and majorly present in the essential oils of Lamiaceae family plants. Many previous reports have shown various biological activities of carvacrol like antioxidant, antiinflammatory and anticancer properties. Recently, we have shown potent anticancer property of carvacrol against prostate cancer cell line DU145. In the current study, we report the chemopreventive and therapeutic potential of carvacrol against another prostate cancer cell line PC-3 with its detailed mechanism of action.

METHODS

To determine the effect of the carvacrol on prostate cancer cells, the cell viability was estimated by MTT assay and cell death was estimated by LDH release assay. The apoptotic assay was performed by DAPI staining and FITC-Annexin V assay. Reactive Oxygen Species (ROS) was estimated by DCFDA method. Cell cycle analysis was performed by flow cytometry. Gene expression analysis was performed by quantitative real time PCR.

RESULTS

Our results suggested that the carvacrol treatment significantly reduced the cell viability of PC-3 cells in a dose- and time-dependent manner. The antiproliferative action of carvacrol was correlated with apoptosis which was confirmed by nuclear condensation, FITC-Annexin V assay, modulation in expression of Bax, Bcl-2 and caspase activation. The mechanistic insight into carvacrol-induced apoptosis leads to finding of elevated level of Reactive Oxygen Species (ROS) and mitochondrial membrane potential disruption. Cell cycle analysis revealed that carvacrol prevented cell cycle in G0/G1 that was associated with decline in expression of cyclin D1 and Cyclin-Dependent Kinase 4 (CDK4) and augmented expression of CDK inhibitor p21. Having been said the role of hyperactivation of Notch signaling in prostate cancer, we also deciphered that carvacrol could inhibit Notch signaling in PC-3 cells via downregulation of Notch-1, and Jagged-1.

CONCLUSION

Thus, our previous and current findings have established the strong potential of carvacrol as a chemopreventive agent against androgen-independent human prostate cancer cells.

Aerial Parts of Peucedanum chenur Have Anti-Cancer Properties through the Induction of Apoptosis and Inhibition of Invasion in Human Colorectal Cancer Cells

Background:

The Peucedanum species have many pharmacological effects due to the presence of coumarins, flavonoids, phenolic compounds, and essential fatty acids in these species. In this study, for the first time, the anticancer activity of Peucedanum chenur methanolic extract via the induction of apoptosis and inhibition of invasion in HCT-116 human colon cancer cells was investigated.

Methods:

P. chenur methanolic extract effect on HCT-116 cells viability and antioxidant activity were evaluated using MTT assay, DPPH, and iron chelating tests, respectively. Changes in mRNA expression level in a panel of relevant genes were assessed by the quantitative real-time PCR. Also, apoptosis was assessed by cell cycle analysis and Annexin V/PI method, and the effect on cell migration was tested using scratch test.

Results:

P. chenur methanolic extract increased significantly the expression of BAX while decreased the expression of BCL-2, AKT1, FAK, RhoA, and MMP genes compared to the control group. BAX/BCL-2 ratio and apoptosis elevated, whereas cell migration reduced significantly. Besides, our extract showed an appropriate antioxidant activity.

Conclusion:

P. chenur may be introduced as a new chemopreventive agent in medicine due to its notable power in terms of induction of apoptosis and inhibition of invasion.

Liquiritin inhibits proliferation and induces apoptosis in HepG2 hepatocellular carcinoma cells via the ROS-mediated MAPK/AKT/NF-κB signaling pathway

Liquiritin (LIQ), a major constituent of Glycyrrhiza Radix, exhibits various pharmacological activities. In this study, to explore the potential anti-cancer effects and its underlying molecular mechanisms of LIQ in hepatocellular carcinoma (HCC) cells. LIQ significantly decreased viability and induced apoptosis in HepG2 cells by decreasing mitochondrial membrane potential and regulating Bcl-2 family proteins, cytochrome c, cle-caspase-3, and cle-PARP. The cell cycle analysis and western blot analysis revealed that LIQ induced G2/M phase arrest through increased expression of p21 and decreased levels of p27, cyclin B, and CDK1/2. The flow cytometry and western blot analysis also suggested that LIQ promoted the accumulation of ROS in HepG2 cells and up-regulated the phosphorylation expression levels of p38 kinase, c-Jun N-terminal kinase (JNK), and inhibitor of NF-κB (IκB-α); the phosphorylation levels of extracellular signal-regulated kinase (ERK), protein kinase B (AKT), signal transducer activator of transcription 3 (STAT3), and nuclear factor kappa B (NF-κB) were down-regulated. However, these effects were reversed by N-acetyl-L-cysteine (NAC), MAPK, and AKT inhibitors. The findings demonstrated that LIQ induced cell cycle arrest and apoptosis via the ROS-mediated MAPK/AKT/NF-κB signaling pathway in HepG2 cells, and the LIQ may serve as a potential therapeutic agent for the treatment of human HCC.

The Mitochondrial Ca2+ Overload via Voltage-Gated Ca2+ Entry Contributes to an Anti-Melanoma Effect of Diallyl Trisulfide

Allium vegetables such as garlic (Allium sativum L.) are rich in organosulfur compounds that prevent human chronic diseases, including cancer. Of these, diallyl trisulfide (DATS) exhibits anticancer effects against a variety of tumors, including malignant melanoma. Although previous studies have shown that DATS increases intracellular calcium (Ca2+) in different cancer cell types, the role of Ca2+ in the anticancer effect is obscure. In the present study, we investigated the Ca2+ pathways involved in the anti-melanoma effect. We used melittin, the bee venom that can activate a store-operated Ca2+ entry (SOCE) and apoptosis, as a reference. DATS increased apoptosis in human melanoma cell lines in a Ca2+-dependent manner. It also induced mitochondrial Ca2+ (Ca2+mit) overload through intracellular and extracellular Ca2+ fluxes independently of SOCE. Strikingly, acidification augmented Ca2+mit overload, and Ca2+ channel blockers reduced the effect more significantly under acidic pH conditions. On the contrary, acidification mitigated SOCE and Ca2+mit overload caused by melittin. Finally, Ca2+ channel blockers entirely inhibited the anti-melanoma effect of DATS. Our findings suggest that DATS explicitly evokes Ca2+mit overload via a non-SOCE, thereby displaying the anti-melanoma effect.

Eriodictyol exerts potent anticancer activity against A549 human lung cancer cell line by inducing mitochondrial-mediated apoptosis, G2/M cell cycle arrest and inhibition of m-TOR/PI3K/Akt signalling pathway

INTRODUCTION

Eriodictyol is an important flavonoid and is commonly present across the plant kingdom. Flavonoids have been reported to show incredible pharmacological potential. However, the anticancer activity of the important flavonoid eriodictyol has not been well reported. In the present study we determined its anticancer potential against the human lung cancer cell line A549.

MATERIAL AND METHODS

The initial cytotoxicity induced by eriodictyol was measured by MTT assay. Flow cytometry was used to study the effects of eriodictyol on apoptosis, cell cycle phase distribution and mitochondrial membrane potential loss. The comet assay was used to measure DNA damage induced by eriodictyol in cancer cells while the western blot assay indicated effects of the compound on Bax/Blc-2 and PI3K/AKT/m-TOR proteins.

RESULTS

The results showed that eriodictyol has an IC₅₀ value of 50 μM against human lung cancer cells as compared to the IC₅₀ of 95 µM against non-cancerous FR2 cells. The molecule exerted its anticancer activity through induction of apoptosis by regulating the Bcl-2/Bax signalling pathway. It caused cell cycle arrest of human lung cancer A549 cells at G2/M phase. Eriodictyol was also found to cause a reduction of the mitochondrial membrane potential in a dose-dependent manner. Additionally, eriodictyol effectively inhibited the mTOR/PI3K/Akt signalling pathway in a dose-dependent manner.

CONCLUSIONS

Based on the above findings, we conclude that eriodictyol exerts its anticancer activity through induction of mitochondrial apoptosis and G2/M cell cycle arrest and inhibition of the TOR/PI3K/Akt cascade, indicating that it may have potential as a lead compound in the treatment of lung cancer, provided further in depth studies are done.

Cancer: Thymoquinone antioxidant/pro-oxidant effect as potential anticancer remedy

Recently, there is growing interest in the natural bioactive components having anticancer activity. Thymoquinone (TQ), the principle active constituent of black seed (Nigella sativa), has promising properties including anticancer and chemosensitizing peculiarities. The anticancer power of TQ is accomplished by several aspects; including promotion of apoptosis, arrest of cell cycle and ROS generation. In addition, it boosts the immune system and lessens the side effects associated with traditional anticancer therapy. TQ also controls angiogenesis and cancer metastasis. This review focuses on the potential aspects and mechanisms by which TQ acquires its actions.

Phase II Trial of Chemopreventive Effects of Levonorgestrel on Ovarian and Fallopian Tube Epithelium in Women at High Risk for Ovarian Cancer: An NRG Oncology Group/GOG Study

A large body of epidemiologic evidence has shown that use of progestin-containing preparations lowers ovarian cancer risk. The purpose of the current study was to gather further preclinical evidence supporting progestins as cancer chemopreventives by demonstrating progestin-activation of surrogate endpoint biomarkers pertinent to cancer prevention in the genital tract of women at increased risk of ovarian cancer. There were 64 women enrolled in a multi-institutional randomized trial who chose to undergo risk-reducing bilateral salpingo-oophorectomy (BSO) and to receive the progestin levonorgestrel or placebo for 4 to 6 weeks prior to undergoing BSO. The ovarian and fallopian tube epithelia (FTE) were compared immunohistochemically for effects of levonorgestrel on apoptosis (primary endpoint). Secondary endpoints included TGFβ isoform expression, proliferation, and karyometric features of nuclear abnormality. In both the ovary and fallopian tube, levonorgestrel did not confer significant changes in apoptosis or expression of the TGFβ1, 2, or 3 isoforms. In the ovarian epithelium, treatment with levonorgestrel significantly decreased the proliferation index. The mean ovarian Ki-67 value in the placebo arm was 2.027 per 100 cells versus 0.775 per 100 cells in the levonorgestrel arm (two-sided P value via Mann-Whitney U test = 0.0114). The karyometric signature of nuclei in both the ovarian and FTE deviated significantly from normal controls (women at average risk of ovarian cancer), but was significantly less abnormal in women treated with levonorgestrel. These karyometric data further support the idea that progestins may clear genetically abnormal cells and act as chemopreventive agents against ovarian and fallopian tube cancer.

Induction of Apoptosis Scutellaria baicalensis Georgi Root Extract by Inactivation of the Phosphatidyl Inositol 3-kinase/Akt Signaling Pathway in Human Leukemia U937 Cells

Background

The roots of Scutellaria baicalensis Georgi (Labiatae) have been widely used in traditional medicine for treatment of various diseases. In this study, we investigated the effects of ethanol extracts of S. baicalensis roots (EESB) on the growth ofn human leukemia U937 cells.

Methods

The effect of EESB on cell viability was measured by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Apoptosis was determined using 4,6-diamidino-2-phenyllindile staining and flow cytometry. The effects of EESB on the expression of regulatory proteins of apoptosis and phosphatidyl inositol 3-kinase (PI3K)/Akt signaling were determined by Western blotting. Caspase activity and mitochondrial membrane potential (MMP) were measured using flow cytometric analysis.

Results

EESB significantly inhibited the growth of U937 cells and induced apoptosis, which was associated with down-regulation of anti-apoptotic Bcl-2, up-regulation of pro-apoptotic Bax, the loss of MMP and activation of caspase-9 and -3. We also found that EESB enhanced the expression of death receptors (DRs) and their associated ligands and induced the activation of caspase-8 and truncation of Bid. In addition, EESB suppressed PI3K/Akt signaling and EESB-induced apoptosis and growth inhibition were further increased by inhibition of PI3K activity.

Conclusions

Our results indicated that the pro-apoptotic effect of EESB was mediated through the activation of DR-mediated intrinsic and mitochondria-mediated extrinsic apoptosis pathways and inhibition of the PI3K/Akt signaling in U937 cells.

Anticancer activity of grassy Hystrix brachyura bezoar and its mechanisms of action: An in vitro and in vivo based study

Porcupine bezoar (PB) is a calcified undigested material generally found in porcupine's (Hystrix brachyura) gastrointestinal tract. The bezoar is traditionally used in South East Asia and Europe for the treatment of cancer, poisoning, dengue, typhoid, etc. However, limited scientific studies have been performed to verify its anticancer potential to substantiate its traditional claims in the treatment of cancers. Hence, this study was aimed at investigating the in vitro and in vivo anticancer properties of two grassy PB aqueous extract (PB-A and PB-B) using A375 cancer cell line and zebrafish model, respectively. This paper presents the first report on in vitro A375 cell viability assay, apoptosis assay, cell cycle arrest assay, migration assay, invasion assay, qPCR experimental assay and in vivo anti-angiogenesis assay using the grassy PBs. Experimental findings revealed IC₅₀ value are 26.59 ± 1.37 μg/mL and 30.12 ± 3.25 μg/mL for PB-A and PB-B respectively. PBs showed anti-proliferative activity with no significant cytotoxic effect on normal human dermal fibroblast (NHDF). PBs were also found to induce apoptosis via intrinsic pathway and arrest cell cycle at G2/M phase. Additionally, the findings indicated its ability to debilitate migration and invasion of A375 cells. Further evaluation using embryo zebrafish model revealed LC₅₀ = 450.0 ± 2.50 μg/mL and 58.7 ± 5.0 μg/mL for PB-A and PB-B which also exerted anti-angiogenesis effect in zebrafish. Moreover, stearic acid, ursodeoxycholic acid and pregnenolone were identified as possible metabolites that might contribute to the anticancer effect of the both PBs. Overall, this study demonstrated that PB-A and PB-B possess potential in vitro and in vivo anticancer effects which are elicited through selective cytotoxic effect, induction of apoptosis, inhibition of migration and invasion and anti-angiogenesis. This study provides scientific evidence that the porcupine bezoar do possess anti-cancer efficacy and further justifies its traditional utility. However, more experiments with higher vertebrae models are still warranted to validate its traditional claims as an anticancer agent.

A flavonoid-rich extract from bergamot juice prevents carcinogenesis in a genetic model of colorectal cancer, the Pirc rat (F344/NTac-Apcam1137)

PURPOSE

To determine the potential of a flavonoid-rich extract from bergamot juice (BJe) to prevent colorectal carcinogenesis (CRC) in vivo.

MAIN METHODS

Pirc rats (F344/NTac-Apc^am1137), mutated in Apc, the key gene in CRC, were treated with two different doses of BJe (35 mg/kg or 70 mg/kg body weight, respectively) mixed in the diet for 12 weeks. Then, the entire intestine was surgically removed and dissected for histological, immunohistochemical and molecular analyses.

RESULTS

Rats treated with BJe showed a significant dose-related reduction in the colon preneoplastic lesions mucin-depleted foci (MDF). Colon and small intestinal tumours were also significantly reduced in rats supplemented with 70 mg/kg of BJe. To elucidate the involved mechanisms, markers of inflammation and apoptosis were determined. Compared to controls, colon tumours from BJe 70 mg/kg-supplemented rats showed a significant down-regulation of inflammation-related genes (COX-2, iNOS, IL-1β, IL-6 and IL-10 and Arginase 1). Moreover, in colon tumours from rats fed with 70 mg/kg BJe, apoptosis was significantly higher than in controls. Up-regulation of p53 and down-regulation of survivin and p21 genes was also observed.

CONCLUSIONS

These data indicate a strong chemopreventive activity of BJe that, at least in part, is due to its pro-apoptotic and anti-inflammatory actions. This effect could be exploited as a strategy to prevent CRC in high-risk patients.

Antrodin C, an NADPH Dependent Metabolism, Encourages Crosstalk between Autophagy and Apoptosis in Lung Carcinoma Cells by Use of an AMPK Inhibition-Independent Blockade of the Akt/mTOR Pathway

The current study aims to explore the possible anti-lung carcinoma activity of ADC as well as the underlying mechanisms by which ADC exerts its actions in NSCLC. Findings showed that ADC potently inhibited the viability of SPCA-1, induced apoptosis triggered by ROS, and arrested the cell cycle at the G2/M phase via a P53 signaling pathway. Interestingly, phenomena such as autophagosomes accumulation, conversion of the LC3-I to LC3-II, etc., indicated that autophagy could be activated by ADC. The blockage of autophagy-augmented ADC induced inhibition of cell proliferation, while autophagy activation restored cell death, indicating that autophagy had a protective effect against cell death which was induced by ADC treatment. Meanwhile, ADC treatment suppressed both the Akt/mTOR and AMPK signaling pathways. The joint action of both ADC and the autophagy inhibitor significantly increased the death of SPCA-1. An in vitro phase I metabolic stability assay showed that ADC was highly metabolized in SD rat liver microsomes and moderately metabolized in human liver microsomes, which will assist in predicting the outcomes of clinical pharmacokinetics and toxicity studies. These findings imply that blocking the Akt/mTOR signaling pathway, which was independent of AMPK inhibition, could activate ADC-induced protective autophagy in non-small-cell lung cancer cells.

Hystrix brachyura Bezoar Characterization, Antioxidant Activity Screening, and Anticancer Activity on Melanoma Cells (A375): A Preliminary Study

Porcupine bezoars (PBs) are masses of undigested calcareous concretions formed within the gastrointestinal tract. There are undocumented claims that PBs have antioxidant activity and can treat cancers. However, limited scientific study has been carried out to verify these traditional claims. Hence, this study was conducted to characterize the chemical profile and validate the antioxidant and anticancer activity against melanoma cells (A375). PB extract was initially subjected to Fourier-transform infrared spectroscopy (FTIR), gas chromatography⁻mass spectrometry (GCMS), total phenolic content (TPC), and total flavonoid content (TFC) analyses. The bioautography of antioxidant assays, namely 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazy (DPPH), and β-carotene was performed. An in vitro A375 cell viability assay, apoptosis assay, cell cycle arrest assay, and gene expression assay were carried out as well. The experimental finding revealed 5,10-diethoxy-2,3,7,8-tetrahydro-1H,6H-dipyrrolo[1,2-a:1',2'-d]pyrazine, ursodeoxycholic acid, and cholest-5-en-3-ol (3 beta)-, carbonochloridate are major compounds detected in PB extract. PB extract has low phenolic content, viz. 698.7 ± 0.93 (µg GAE/5 mg dry weight). The bioautography antioxidant assays revealed a potent antioxidant effect (ABTS > DPPH > β-carotene), with free radical scavenging activity. Furthermore, PB extract exhibited dose- and time-dependent inhibition of cancer activity on A375 cells due to the exhibition of apoptosis via an intrinsic pathway.