Cocoa tea (Camellia ptilophylla) induces mitochondria-dependent apoptosis in HCT116 cells via ROS generation and PI3K/Akt signaling pathway

Characterization of a new Camellia plant resource with low caffeine and high theobromine for production of a novel natural low-caffeine tea

Yuanbaoshancha (YBSC) is characterized as a new wild tea relative morphologically and phytochemically distinguished from the closest wild tea plants Rongjiangcha (Camellia yungkiangensis, RJC) and Tulecha (Camellia costata, TLC). YBSC young leaves contain higher tea polyphenol and theobromine contents but lower caffeine and theanine as compared with RJC, TLC, and other tea landraces and modern cultivars. The major alkaloid detected in YBSC, TLC, and RJC is theobromine while caffeine is a minor; the primary catechins in YBSC leaves are non-galloylated catechins, significantly different from Camellia sinensis and other low-caffeine tea resources. The unique phytochemical profiles featured YBSC black tea with extremely lower caffeine and higher theobromine, as well as unique flavors and health benefits. This botanical characterization of YBSC and two related low-caffeine wild tea resources lays a foundation for future better utilization for the production of a highly valuable natural low-caffeine/high-theobromine tea.

Chemical compounds

Caffeine (PubChem CID: 2519); Theobromine (PubChem CID: 5429); Catechins (PubChem CID: 9064); Epigallocatechin gallate (PubChem CID: 65064); Theanine (PubChem CID: 439378); Jasmone (PubChem CID: 1549018); cis-3-Hexenyl hexanoate (PubChem CID: 5352543); Hexyl 2-methylbutanoate (PubChem CID: 24838).

Effects of Mao tea from Nankun Mountain on nonalcoholic fatty liver disease in mice

Non-alcoholic fatty liver disease (NAFLD) poses a significant health threat due to its potential progression to liver fibrosis, cirrhosis, and even liver cancer. Without proper management, NAFLD can lead to severe complications and significantly impact overall health and longevity. This study explores the potential anti-steatosis effects of Nankun Mountain Mao tea (MT) on hepatic lipid accumulation using both in vitro and in vivo models. In vitro experiments reveal that MT reduces lipid accumulation in hepatocytes and counteracts hepatic steatosis induced by palmitic acid and oleic acid. In vivo investigations on high-fat diet (HFD)-fed and high-fat, fructose, and cholesterol (HFFC)-fed mice demonstrate that MT administration alleviates hepatic steatosis by reducing lipid accumulation, enhancing liver function, and mitigating inflammation. Transcriptomic analyses unveil the molecular mechanisms underlying the impact of MT on lipid metabolism and inflammation. It turns out that MT inhibits de novo lipid synthesis and NF-κB pathway against NAFLD. Furthermore, target prediction analysis identifies potential bioactive components group (BCG) within MT that may contribute to its anti-steatosis properties. Validation studies on primary hepatocytes confirm the effectiveness of these bioactive components in diminishing lipid accumulation and inflammation, suggesting their role in the therapeutic efficacy of MT against NAFLD.

pH-Sensitive Nanoparticles of Epigallocatechin-3-Gallate in Enhanced Colorectal Cancer Therapy

AIM

Encapsulating epigallocatechin-3-gallate (EGCG) in pH-sensitive polymeric nanoparticles for targeted delivery of drugs could revolutionize colorectal cancer treatment.

MATERIALS & METHODS

Nanoparticles were synthesized to release drugs at colon pH. Dynamic light scattering measured their average diameter and ζ-potential, while differential scanning calorimetry and x-ray diffraction assessed EGCG encapsulation.

RESULTS

The nanoparticles showed stability and bioavailability in the gastrointestinal tract, efficiently encapsulating and releasing over 93% of EGCG at pH 7.2. They enhanced cytotoxicity against HT-29 cells and demonstrated antibacterial properties, increasing apoptosis and cell cycle arrest.

CONCLUSION

The study underscores the potential of nanoparticles in enhancing EGCG delivery for colorectal cancer therapy, aiming to minimize side effects and improve therapeutic outcomes.

Natural products and mitochondrial allies in colorectal cancer therapy

Colorectal cancer (CRC) is a globally prevalent malignancy with a high potential for metastasis. Existing cancer treatments have limitations, including drug resistance and adverse effects. Researchers are striving to develop effective therapies to address these challenges. Impressively, contemporary research has discovered that many natural products derived from foods, plants, insects, and marine invertebrates can suppress the progression, metastasis, and invasion of CRC. In this review, we conducted a comprehensive search of the CNKI, PubMed, Embase, and Web of Science databases from inception to April 2023 to evaluate the efficacy of natural products targeting mitochondria to fight against CRC. Mitochondria are intracellular energy factories involved in cell differentiation, signal transduction, cell cycle regulation, apoptosis, and tumorigenesis. The identified natural products have been classified and summarized based on their mechanisms of action. These findings indicate that natural products can induce apoptosis in colorectal cancer cells by inhibiting the mitochondrial respiratory chain, ROS elevation, disruption of mitochondrial membrane potential, the release of pro-apoptotic factors, modulation of the Bcl-2 protein family to facilitate cytochrome c release, induction of apoptotic vesicle activity by activating the caspase protein family, and selective targeting of mitochondrial division. Furthermore, diverse apoptotic signaling pathways targeting mitochondria, such as the MAPK, p53, STAT3, JNK and AKT pathway, have been triggered by natural products. Natural products such as diosgenin, allopurinol, and clausenidin have demonstrated low toxicity, high efficacy, and multi-targeted properties. Mitochondria-targeting natural products have great potential for overcoming the challenges of CRC therapy.

Copper exposure induces ovarian granulosa cell apoptosis by activating the caspase-dependent apoptosis signaling pathway and corresponding changes in microRNA patterns

Environmental copper (Cu) contamination is a complex worldwide public health problem. However, information on the effects of Cu pollution on human reproduction is limited. Although our previous studies have indicated that Cu exposure disrupts ovarian folliculogenesis, the underlying mechanism needs to be further explored. In this study, human luteinized ovarian granulosa cells and a rat animal model were used to investigate whether Cu exposure affects ovarian follicle development by inducing apoptosis and to elucidate the possible mechanisms. The results showed that Cu exposure from weaning to sexual maturity significantly decreased the proportion of preantral follicles but increased the proportion of atretic follicles (P < 0.05). In addition, 6 mg/kg Cu increased the proportion of antral follicles, while 12 and 25 mg/kg Cu decreased it (P < 0.05). We also found that 6 mg/kg Cu exposure inhibited apoptosis of ovarian granulosa cells, while 12 and 25 mg/kg Cu promoted apoptosis (P < 0.05). Experiments on primary human luteinized ovarian granulosa cells suggested that higher levels of Cu exposure induced a significant increase in the mRNA levels of Bcl2 Bax , Fas, Caspase8, and Caspase3 (P < 0.05), and the protein levels of BAX, BCL2, CASPASE3, CASPASE8, CLE-CASPASE3, CLE-CASPASE8 and BAX/BCL2 were also increased (P < 0.05). miRNA chip analyses identified a total of 95 upregulated and 10 downregulated miRNAs in human luteinized granulosa cells exposed to Cu. Hsa-miR-19b-3p, hsa-miR-19a-3p, miR-548ar-3p, hsa-miR-652-5p, and hsa-miR-29b-5p were decreased after Cu exposure (P < 0.05). Additionally, the level of hsa-miR-144-5p was increased (P < 0.05). Together, our results reveal that Cu exposure induces abnormal ovarian folliculogenesis by inducing ovarian granulosa cell apoptosis, which is triggered by the caspase-dependent apoptosis signaling pathway, and that miRNAs may be involved in this process.

N-methylsansalvamide elicits antitumor effects in colon cancer cells in vitro and in vivo by regulating proliferation, apoptosis, and metastatic capacity

N-methylsansalvamide (MSSV), a cyclic pentadepsipeptide, was obtained from a strain of Fusarium solani f. radicicola. The current study investigated the anti-colorectal cancer effect of MSSV. MSSV exhibited the inhibition of the proliferation in HCT116 cells via induction of G0/G1 cell cycle arrest by downregulating CDK 2, CDK6, cyclin D, and cyclin E, and upregulating p21WAF1 and p27KIP1. Decreased phosphorylation of AKT was observed in MSSV-treated cells. Moreover, MSSV treatment induced caspase-mediated apoptosis through elevating the level of cleaved caspase 3, cleaved PARP, cleaved caspase 9, and pro-apoptotic Bax. MSSV revealed the declined MMP-9 level mediated by reduction in the binding activity of AP-1, Sp-1, and NF-κB motifs, which led to the migration and invasion of HCT116 cells. In vitro metabolism with rat liver S9 fractions was performed to examine the effect of MSSV metabolites. The metabolic process enhanced the inhibitory effect of MSSV on the HCT116 cell proliferation via decline of cyclin D1 expression and AKT phosphorylation. Finally, oral administration of MSSV inhibited the tumor growth of HCT116 xenograft mice. These results suggest that MSSV is a potential anti-tumor agent in colorectal cancer treatment.

Special tea products featuring functional components: Health benefits and processing strategies

The functional components in tea confer various potential health benefits to humans. To date, several special tea products featuring functional components (STPFCs) have been successfully developed, such as O-methylated catechin-rich tea, γ-aminobutyric acid-rich tea, low-caffeine tea, and selenium-rich tea products. STPFCs have some unique and enhanced health benefits when compared with conventional tea products, which can meet the specific needs and preferences of different groups and have huge market potential. The processing strategies to improve the health benefits of tea products by regulating the functional component content have been an active area of research in food science. The fresh leaves of some specific tea varieties rich in functional components are used as raw materials, and special processing technologies are employed to prepare STPFCs. Huge progress has been achieved in the research and development of these STPFCs. However, the current status of these STPFCs has not yet been systematically reviewed. Here, studies on STPFCs have been comprehensively reviewed with a focus on their potential health benefits and processing strategies. Additionally, other chemical components with the potential to be developed into special teas and the application of tea functional components in the food industry have been discussed. Finally, suggestions on the promises and challenges for the future study of these STPFCs have been provided. This paper might shed light on the current status of the research and development of these STPFCs. Future studies on STPFCs should focus on screening specific tea varieties, identifying new functional components, evaluating health-promoting effects, improving flavor quality, and elucidating the interactions between functional components.

GDF11, a target of miR-32-5p, suppresses high-glucose-induced mitochondrial dysfunction and apoptosis in HK-2 cells through PI3K/AKT signaling activation

PURPOSE

To investigate the role and underlying mechanism of GDF11 on diabetic nephropathy (DN)-related mitochondrial dysfunction and apoptosis.

METHODS

A DN model of rats was established in this study. Human Kidney-2 (HK-2) cells were cultured under high-glucose (HG) condition with or without recombinant GDF11 (rGDF11). Mitochondrial morphology of HK-2 cells was analyzed by transmission electron microscope and MitoTracker Red CMXRos staining. Mitochondrial membrane potential (MMP) and ROS production were monitored using JC-1 assay kit and MitoSOX staining, respectively. Cell apoptosis was detected by TUNEL or flow cytometry assays.

RESULTS

Herein, we observed that GDF11 was down-regulated in renal cortex and serum of DN rats, which was accompanied by renal mitochondrial morphological abnormalities. In line with the findings in vivo, HK-2 cells exposed to HG presented with mitochondrial morphological alterations and further apoptosis accompanied by GDF11 reduction. In addition, HG promoted a decrease in MMP while an increase in mitochondrial ROS production. Conversely, rGDF11 treatment significantly alleviated these HG-induced mitochondrial defects in HK-2 cells. Meanwhile, HK-2 cell apoptosis induced by HG was simultaneously suppressed by rGDF11. Mechanistically, the decreased levels of p-AKT induced by HG were attenuated after rGDF11 administration. Inhibition of the PI3K/AKT pathway resisted the effects of rGDF11 on the MMP and apoptosis of HK-2 cells. In addition, we identified that GDF11 is a target of miR-32-5p. Up-regulation of miR-32-5p could inhibit the expression of GDF11.

CONCLUSION

rGDF11 treatment rescued HG-induced HK-2 cell mitochondrial dysfunction and apoptosis, which may be dependent on the activation of the PI3K/AKT pathway.

A SERS-Based Dual-Parameter Monitoring Nanoprobe of ROS and PI3K/Akt during Ginsenoside Rg3-Induced Cell Apoptosis

Both the reactive oxygen species (ROS) level and Phosphatidylinositol 3 Kinase (PI3K) protein content are two crucial parameters for characterizing states of cell apoptosis. Current methods measure these parameters with two different techniques, respectively, which usually lead to evaluation contingency. Ginsenoside Rg3 exhibits an excellent anticancer effect, which is enacted by the Phosphatidylinositol 3 Kinase/Protein Kinase B (PI3K/Akt) pathway involving ROS; however, the precise mechanism that induces cell apoptosis remains unknown. This is due to the lack of information on quantitative intracellular ROS and PI3K. Here, we used a surface-enhanced Raman scattering (SERS)-based boric acid nanoprobe to monitor the intracellular ROS level and phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P₃) content, which reflects the regulatory effect of the PI3K/Akt pathway. After treatment with ginsenoside Rg3, the PI3K/Akt content first increased and then decreased as the ROS level increased. Moreover, when the ROS level significantly increased, the mitochondrial membrane potential reduced, thus indicating the dynamic regulation effect of intracellular ROS level on the PI3K/Akt pathway. Importantly, in addition to avoiding evaluation contingency, which is caused by measuring the aforementioned parameters with two different techniques, this SERS-based dual-parameter monitoring nanoprobe provides an effective solution for simultaneous ROS level and PI3K content measurements during cell apoptosis. Furthermore, the intracellular ROS level was also able to have a dynamic regulatory effect on the PI3K/Akt pathway, which is essential for studying ROS/PI3K/Akt-pathway-related cell apoptosis and its activation mechanism.

Induction of Apoptosis via Inactivating PI3K/AKT Pathway in Colorectal Cancer Cells Using Aged Chinese Hakka Stir-Fried Green Tea Extract

Food extract supplements, with high functional activity and low side effects, play a recognized role in the adjunctive therapy of human colorectal cancer. The present study reported a new functional beverage, which is a type of Chinese Hakka stir-fried green tea (HSGT) aged for several years. The extracts of the lyophilized powder of five HSGT samples with different aging periods were analyzed with high-performance liquid chromatography. The major components of the extract were found to include polyphenols, catechins, amino acids, catechins, gallic acid and caffeine. The tea extracts were also investigated for their therapeutic activity against human colorectal cancer cells, HT-29, an epithelial cell isolated from the primary tumor. The effect of different aging time of the tea on the anticancer potency was compared. Our results showed that, at the cellular level, all the extracts of the aged teas significantly inhibited the proliferation of HT-29 in a concentration-dependent manner. In particular, two samples prepared in 2015 (15Y, aged for 6 years) and 2019 (19Y, aged for 2 years) exhibited the highest inhibition rate for 48 h treatment (cell viability was 50% at 0.2 mg/mL). Further, all the aged tea extracts examined were able to enhance the apoptosis of HT-29 cells (apoptosis rate > 25%) and block the transition of G1/S phase (cell-cycle distribution (CSD) from <20% to >30%) population to G2/M phase (CSD from nearly 30% to nearly 10%) at 0.2 mg/mL for 24 h or 48 h. Western blotting results also showed that the tea extracts inhibited cyclin-dependent kinases 2/4 (CDK2, CDK4) and CylinB1 protein expression, as well as increased poly ADP-ribose polymerase (PRAP) expression and Bcl2-associated X (Bax)/B-cell lymphoma-2 (Bcl2) ratio. In addition, an upstream signal of one of the above proteins, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling, was found to be involved in the regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the extracts of the aged tea. Therefore, our study reveals that traditional Chinese aged tea (HSGT) may inhibit colon cancer cell proliferation, cell-cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling.

Design and Synthesis of Coumarin Derivatives as Cytotoxic Agents through PI3K/AKT Signaling Pathway Inhibition in HL60 and HepG2 Cancer Cells

In this study, a series of coumarin derivatives, either alone or as hybrids with cinnamic acid, were synthesized and evaluated for their cytotoxicity against a panel of cancer cells using the MTT assay. Then, the most active compounds were inspected for their mechanism of cytotoxicity by cell-cycle analysis, RT-PCR, DNA fragmentation, and Western blotting techniques. Cytotoxic results showed that compound (4) had a significant cytotoxic effect against HL60 cells (IC₅₀ = 8.09 µM), while compound (8b) had a noticeable activity against HepG2 cells (IC₅₀ = 13.14 µM). Compounds (4) and (8b) mediated their cytotoxicity via PI3K/AKT pathway inhibition. These results were assured by molecular docking studies. These results support further exploratory research focusing on the therapeutic activity of coumarin derivatives as cytotoxic agents.

Inhibition and potential treatment of colorectal cancer by natural compounds via various signaling pathways

Colorectal cancer (CRC) is a common type of malignant digestive tract tumor with a high incidence rate worldwide. Currently, the clinical treatment of CRC predominantly include surgical resection, postoperative chemotherapy, and radiotherapy. However, these treatments contain severe limitations such as drug side effects, the risk of recurrence and drug resistance. Some natural compounds found in plants, fungi, marine animals, and bacteria have been shown to inhibit the occurrence and development of CRC. Although the explicit molecular mechanisms underlying the therapeutic effects of these compounds on CRC are not clear, classical signaling transduction pathways such as NF-kB and Wnt/β-catenin are extensively regulated. In this review, we have summarized the specific mechanisms regulating the inhibition and development of CRC by various types of natural compounds through nine signaling pathways, and explored the potential therapeutic values of these natural compounds in the clinical treatment of CRC.

Newly Synthesized Pyrazolinone Chalcones as Anticancer Agents via Inhibiting the PI3K/Akt/ERK1/2 Signaling Pathway

A series of novel pyrazolinone chalcones 3-9 have been synthesized through the condensation of azo pyrazolinone derivatives with various aromatic aldehydes. Spectroscopic techniques and elemental analysis have both corroborated this. Furthermore, all compounds were screened in silico for their ability to inhibit cancer proliferation and metastasis by targeting the PI3K/Akt signaling pathway. This inhibitory pathway might be an efficient approach for the death of cancer cells, angiogenesis, and metastasis prevention. Our results indicated that only compound 6b was the top-ranked. It demonstrated the highest binding energies of -11.1 and -10.7 kcal/mol against the target proteins PI3K and Akt, respectively; thus, it was chosen for in vitro studies. Compound 6b exhibited the most effective cytotoxic impact against the Caco cell line with IC50 of 23.34 ± 0.14 μM. Furthermore, it showed significant inhibition of PI3K/Akt proteins and oxidative stress, leading to elevated Bax and p53 expression, reduced Bcl-2 expression, and triggered cell cycle arrest at the sub-G0/G1 phase. Additionally, it showed significant downregulation of the Raf-1 gene, leading to ERK1/2 protein inhibition. These findings demonstrate that compound 6b obeyed Lipinski's rule of five and might be used as a favored scaffold for cancer treatment by inhibiting proliferation and metastasis via inhibition of the PI3K/Akt and Raf-1/ERK1/2 signaling pathways.

Reactive Oxygen Species Bridge the Gap between Chronic Inflammation and Tumor Development

According to numerous animal studies, adverse environmental stimuli, including physical, chemical, and biological factors, can cause low-grade chronic inflammation and subsequent tumor development. Human epidemiological evidence has confirmed the close relationship between chronic inflammation and tumorigenesis. However, the mechanisms driving the development of persistent inflammation toward tumorigenesis remain unclear. In this study, we assess the potential role of reactive oxygen species (ROS) and associated mechanisms in modulating inflammation-induced tumorigenesis. Recent reports have emphasized the cross-talk between oxidative stress and inflammation in many pathological processes. Exposure to carcinogenic environmental hazards may lead to oxidative damage, which further stimulates the infiltration of various types of inflammatory cells. In turn, increased cytokine and chemokine release from inflammatory cells promotes ROS production in chronic lesions, even in the absence of hazardous stimuli. Moreover, ROS not only cause DNA damage but also participate in cell proliferation, differentiation, and apoptosis by modulating several transcription factors and signaling pathways. We summarize how changes in the redox state can trigger the development of chronic inflammatory lesions into tumors. Generally, cancer cells require an appropriate inflammatory microenvironment to support their growth, spread, and metastasis, and ROS may provide the necessary catalyst for inflammation-driven cancer. In conclusion, ROS bridge the gap between chronic inflammation and tumor development; therefore, targeting ROS and inflammation represents a new avenue for the prevention and treatment of cancer.

Comparative LC-LTQ-MS-MS Analysis of the Leaf Extracts of Lantana camara and Lantana montevidensis Growing in Egypt with Insights into Their Antioxidant, Anti-Inflammatory, and Cytotoxic Activities

Lantana camara L. and Lantana montevidensis Briq. (F. Verbenaceae) are invasive ornamental weeds native to the tropical regions of Africa and America. The leaves of both species have been traditionally used as infusions for treating fever, rheumatism, and cancer. LC-MS-MS-guided profiling of the methanolic extracts of the leaves of L. camara and L. montevidensis growing in Egypt led to the putative identification of 59 compounds belonging to terpenoids, flavonoids, iridoid glycosides, phenolic acids, and their derivatives. The in-vitro antioxidants and anti-inflammatory and anticancer activities of the two extracts were investigated. L. camara and L. montevidensis inhibited DPPH^• (IC₅₀ = 34.01 ± 1.32 and 47.43 ± 1.74 µg/mL), ABTS⁺ (IC₅₀ = 30.73 ± 1.42 and 40.37 ± 1.51 µg/mL), and superoxide anion (IC₅₀ = 1.57 ± 0.19 and 1.31 ± 0.14 μg/mL) free radicals. A potent anti-inflammatory effect was observed for both species through the inhibition of elastase release in fMLF/CB-induced human neutrophils (IC₅₀ = 2.40 ± 0.16 and 1.90 ± 0.07 μg/mL). The extracts showed significant cytotoxic activity against a panel of cancer cell lines with the most potent activity against Caco cells (IC₅₀ = 45.65 ± 1.64 and 40.67 ± 1.52 µg/mL for L. camara and L. montevidensis, respectively). Western blotting supported by FACS analysis revealed that the extracts inhibited cancer cell proliferation, reduced metastasis, and induced apoptosis resulting in cell cycle arrest. This was achieved via increasing mRNA and protein expressions of p53 and GSK-3β as well as decreasing the expression of PI3K, Akt, and cyclin D1.

Aqueous Extract and Polysaccharide of Aconiti Lateralis Radix Induce Apoptosis and G0/G1 Phase Cell Cycle Arrest by PI3K/AKT/mTOR Signaling Pathway in Mesangial Cells

Mesangial proliferative glomerulonephritis (MesPGN) is a common renal disease that lacks effective drug intervention. Aconiti Lateralis Radix (Fuzi), a natural Chinese medical herb, is found with significant therapeutic effects on various diseases in the clinic. However, its effects on MesPGN have not been reported. This study is aimed to discuss the therapeutic effects of the aqueous extract of Aconiti Lateralis Radix (ALR) and the polysaccharides of Aconiti Lateralis Radix (PALR) on MesPGN as well as the underlying mechanism. In this study, we, firstly, studied the anti-MesPGN mechanism of ALR and PALR. ALR and PALR inhibit the proliferation of the mesangial cells through the PI3K/AKT/mTOR pathway, induce the G0/G1 phase of block and apoptosis, inhibit the activity of Cyclin E and CDK2, increase the expression of Bax, cleaved caspase-8/caspase-8, and cleaved caspase-3/caspase-3 proteins, and effectively inhibit the growth of the mesangial cells. Overall, our data suggest that ALR and PALR may be potential candidates for MesPGN and that PALR is more effective than ALR.

Transcriptome and biochemical analyses of rainbow trout (Oncorhynchus mykiss) RTG-2 gonadal cells in response to BDE-47 stress indicates effects on cell proliferation

2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is a biotoxin of polybrominated diphenyl ether (PBDEs) frequently detected in the environment. Apoptosis and cell cycle arrest are important toxic phenomena of xenobiotics that inhibit cell proliferation. In this study, we investigated the effects of BDE-47 (5 μM, 10 μM, 20 μM, 40 μM) on cell viability, morphology, cell cycle and apoptosis. BDE-47 significantly decreased cell viability, and morphological alterations were observed. The significant increase in cells at G1 phase indicated the occurrence of G1 phase cell cycle arrest in RTG-2 cells. An acridine orange and ethidium bromide (AO/EB) staining assay was employed and revealed the induction of apoptosis in RTG-2 cells. The results indicated that BDE-47 exposure inhibits cell proliferation. Transcriptome analysis was applied for further evidence. A total of 1300 differentially expressed genes (DEGs) were identified in RTG-2 cells, among which 26 DEGs were associated with the cell cycle and apoptosis. Western blotting and qPCR analyses also showed the expression of cell cycle- and apoptosis-related proteins and genes. Mapping the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, p53, Tumor necrosis factor (TNF), Mitogen-activated protein kinase (MAPK), phosphatidylinositide 3-kinase-AKT (PI3K-AKT), and reaction oxygen species (ROS)-mediated signaling pathways were determined to be the major pathways involved in modulating the cell cycle and apoptosis. Since we demonstrated simultaneous ROS overproduction during BDE-47 exposure in a previous study, we speculated a possible explanation for the observation: BDE-47-induced ROS overproduction was the initiating signal, which activated cell cycle arrest and apoptosis and finally inhibited cell proliferation.

In Vitro Anticancer Activity of Novel Co(II) and Ni(II) Complexes of Non-steroidal Anti-inflammatory Drug Niflumic Acid Against Human Breast Adenocarcinoma MCF-7 Cells

Herein, we report the synthesis, characterization and anticancer activity of six novel complexes of non-steroidal anti-inflammatory drug niflumic acid with Co(II) and Ni(II). In vitro cytotoxicity screening in MCF-7, HepG2 and HT-29 cancer cell lines showed that the complex 3 [Co(nif)2(met)(4-pic)] and complex 6 [Ni(nif)2(met)(4-pic)] among all the complexes exhibited the highest cytotoxicity against MCF-7 cells with IC50 values of 11.14 µM and, 41.47 µM, respectively. Besides, all the complexes exhibited significantly higher selectivity towards mouse fibroblast 3T3L1 cells. Further mechanistic studies with both complexes on MCF-7 cells revealed their cytotoxic action through the mitochondrial-dependent apoptotic pathway causing an increase oxidative/nitrosative stress, decrease in mitochondrial membrane potential (ΔΨm), inducing the multicaspase activation and arresting the cell cycle at S phase. q-PCR analysis resulted in an increase in the expression of the apoptotic marker proteins bax, p53 and caspase-3 and -8 in MCF-7 cells, but a decrease in the expression of antiapoptotic bcl-2 gene. Moreover, both complexes induced the apoptosis through the inhibition of PI3K/Akt signaling pathway by decreasing the expression of PI3K and increasing dephosphorylation form of Akt protein. These results provide a significant contribution to the explanation of the anticancer mechanisms of these complexes in MCF-7 cells.

Natural substances derived from herbs or plants are promising sources of anticancer agents against colorectal cancer via triggering apoptosis

OBJECTIVES

Nowadays, one of the most common gastrointestinal cancers is colorectal cancer (CRC). Chemotherapy is still one of the main methods to treat cancer. However, the currently available synthetic chemotherapy drugs often cause serious adverse reactions. Apoptosis is generally considered as an ideal way for induction the death of tumour cells without the body's inflammatory response, and it is reported that lots of natural agents could trigger various cancer cells to apoptosis. The overarching aim of this project was to elucidate the specific mechanisms by which natural substances induce apoptosis in CRC cells and to be used as an alternative therapeutic option in the future.

KEY FINDINGS

The mechanisms for the pro-apoptotic effects of natural substances derived from herbs or plants include death receptor pathway, mitochondrial pathway, endoplasmic reticulum stress pathway, related signal transduction pathways (PI3K/Akt, MAPK, p53 signalling), and so on.

SUMMARY

This paper updated this information regarding the anti-tumour effects of natural agents via induction of apoptosis against CRC, which would be beneficial for future new drug research regarding natural products from herbs or plants.

The Role of Curcumin in Cancer Treatment

Curcumin is a polyphenol extracted from the rhizomes of the turmeric plant, Curcuma longa which has anti-inflammatory, and anticancer properties. Chronic inflammation is associated with the development of cancer. Curcumin acts on the regulation of various immune modulators, including cytokines, cyclooxygenase-2 (COX-2), and reactive oxygen species (ROS), which partly explains its anticancer effects. It also takes part in the downregulation of growth factors, protein kinases, oncogenic molecules and various signaling pathways, such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), c-Jun N-terminal kinase (JNK) and signal transducer and activator of transcription 3 (STAT3) signaling. Clinical trials of curcumin have been completed or are ongoing for various types of cancer. This review presents the molecular mechanisms of curcumin in different types of cancer and the evidence from the most recent clinical trials.

Daphnoretin induces reactive oxygen species-mediated apoptosis in melanoma cells

Research suggests that daphnoretin exhibits a diverse array of antitumor mechanisms and pharmacological activities. However, there is no definitive explanation for the antitumor mechanisms of daphnoretin in malignant melanoma. In the present study, MTT and colony formation assays demonstrated that daphnoretin significantly inhibited the proliferation of melanoma A375 and B16 cells. Following treatment with daphnoretin, apoptotic bodies were observed in A375 and B16 cells via Hoechst 33258 staining. Furthermore, western blot analysis revealed that the apoptosis-related proteins cleaved caspase-3, cleaved caspase-9, Bax, cytochrome c and apoptotic protease-activating factor 1 were significantly upregulated, while the expression levels of caspase-3, caspase-9 and Bcl-2 were downregulated in A375 and B16 cells. Flow cytometry and fluorescence microscopy revealed that daphnoretin induced higher levels of reactive oxygen species (ROS). Therefore, the results of the present study indicated that daphnoretin induced ROS-mediated mitochondria apoptosis in human (A375) and murine (B16) malignant melanoma cells.

Square planar Au(III), Pt(II) and Cu(II) complexes with quinoline-substituted 2,2':6',2″-terpyridine ligands: From in vitro to in vivo biological properties

Cancer is the second leading cause of death worldwide. Cisplatin has challenged cancer treatment; however, resistance and side effects hamper its use. New agents displaying improved activity and more reduced side effects relative to cisplatin are needed. In this work we present the synthesis, characterization and biological activities of three complexes with quinoline-substituted 2,2':6',2″-terpyridine ligand: [Pt(4'-(2-quin)-terpy)Cl](SO₃CF₃) (1), [Au(4'-(2-quin)-terpy)Cl](PF₆)₂·CH₃CN (2) and [Cu(4'-(2-quin)-terpy)Cl](PF₆) (3). The three complexes displayed a high antiproliferative activity in ovarian carcinoma cell line (A2780) and even more noticeable in a colorectal carcinoma cell line (HCT116) following the order 3 > 2 > 1. The complexes IC₅₀ are at least 20 × lower than the IC₅₀ displayed by cisplatin (15.4 μM) in HCT116 cell line while displaying at the same time, much reduced cytotoxicity in a normal dermal fibroblast culture. These cytotoxic activities seem to be correlated with the inclination angles of 2-quin unit to the central pyridine. Interestingly, all complexes can interact with calf-thymus DNA (CT-DNA) in vitro via different mechanisms, although intercalation seems to be the preferred mechanism at least for 2 and 3 at higher concentrations of DNA. Moreover, circular dichroism (CD) data seems to indicate that complex 3, more planar, induces a high destabilization of the DNA double helix (shift from B-form to Z-form). Higher the deviation from planar, the lower the cytotoxicity displayed by the complexes. Cellular uptake may be also responsible for the different cytotoxicity exhibited by complexes with 3 > 2 >1. Complex 2 seems to enter cells more passively while complex 1 and 3 might enter cells via energy-dependent and -independent mechanisms. Complexes 1-3 were shown to induce ROS are associated with the increased apoptosis and autophagy. Moreover, all complexes dissipate the mitochondrial membrane potential leading to an increased BAX/BCL-2 ratio that triggered apoptosis. Complexes 2 and 3 were also shown to exhibit an anti-angiogenic effect by significantly reduce the number of newly formed blood vessel in a CAM model with no toxicity in this in vivo model. Our results seem to suggest that the increased cytotoxicity of complex 3 in HCT116 cells and its potential interest for further translation to pre-clinical mice xenografts might be associated with: 1) higher % of internalization of HCT116 cells via energy-dependent and -independent mechanisms; 2) ability to intercalate DNA and due to its planarity induced higher destabilization of DNA; 3) induce intracellular ROS that trigger apoptosis and autophagy; 4) low toxicity in an in vivo model of CAM; 5) potential anti-angiogenic effect.

A Novel Antioxidant Protects Against Contrast Medium-Induced Acute Kidney Injury in Rats

Many studies proposed that oxidative stress and apoptosis are key mechanisms in the pathogenesis of contrast-induced acute kidney injury (CI-AKI). Xylose-pyrogallol conjugate (XP) is an original effective antioxidant that showed decent antioxidant and anti-apoptosis effect before. Thus the therapeutic effect and mechanism of XP in preventing CI-AKI in the short and long term were investigated in this research. Renal function and histological grade were evaluated to determine the severity of renal injury. Kidney samples were then collected for the measurement of oxidative stress markers and the detection of apoptosis. Transmission electron microscopy (TEM) and western blot of mitochondrial protein were utilized for the analysis of the mitochondrial conditions. The results demonstrated that the CI-AKI rats caused a significant decrease in renal function accompanied by a remarkable increase in Malondialdehyde (MDA), bax, caspase-3, cytochrome c (Cyt C) level, TdT-mediated dUTP nick end labeling (TUNEL) positive apoptotic cells, and damaged mitochondria, while a decline in antioxidase activities and mitochondrial superoxide dismutase 2 (SOD2) expression compared with the control rats. However, when XP (50 or 100 or 200 mg/kg/day) was given orally for consecutive 7 days before CI-AKI modeling, XP (200 mg/kg) showed a better capability to restore renal dysfunction, histopathological appearance, the level of apoptosis, mitochondrial damage, oxidative stress, and fibrosis generation without interference in computed tomographic imaging. Our study indicated that antioxidant XP played a nephroprotective role probably via antiapoptotic and antioxidant mechanisms. Besides, XP may regulate the mitochondria pathway via decreasing the ratio of bax/bcl-2, inhibiting caspase-3 expression, cytochrome c release, and superoxide dismutase 2 activity. Overall, XP as a high-efficient antioxidant may have the potentials to prevent CI-AKI.

The Long Noncoding RNA LOC441461 (STX17-AS1) Modulates Colorectal Cancer Cell Growth and Motility

Simple Summary

Long noncoding RNA dysfunction is crucial for colorectal carcinoma (CRC) development. Whether the dysfunction of LOC441461, a novel lncRNA, can regulate cancer-related signaling pathways in cancer progression remains unclear. Here, we uncover the oncogenic role of LOC441461 in colon cancer cell growth and motility and identify a novel mechanism for LOC441461 knockdown-induced suppression of cancer motility through modulating Ras homolog family member A (RhoA)/Rho-associated protein kinase (ROCK) activity. This is the first report that LOC441461 knockdown impairs cell cycle progression and accelerates the apoptosis of colon cancer cells following chemotherapy drug treatment. The results suggest that LOC441461 expression confers drug sensitivity in colon cancer by inducing apoptosis. Our findings offer new insight into LOC441461 regulation and provide an application for colon cancer therapy in the future.

Abstract

Colorectal carcinoma (CRC) is one of the most prevalent cancers worldwide and has a high mortality rate. Long noncoding RNAs (lncRNAs) have been noted to play critical roles in cell growth; cell apoptosis; and metastasis in CRC. This study determined that LOC441461 expression was significantly higher in CRC tissues than in adjacent normal mucosa. Pathway enrichment analysis of LOC441461-coexpressed genes revealed that LOC441461 was involved in biological functions related to cancer cell growth and motility. Knockdown of the LOC441461 expression significantly suppressed colon cancer cell growth by impairing cell cycle progression and inducing cell apoptosis. Furthermore, significantly higher LOC441461 expression was discovered in primary colon tumors and metastatic liver tumors than in the corresponding normal mucosa, and LOC441461 knockdown was noted to suppress colon cancer cell motility. Knockdown of LOC441461 expression suppressed the phosphorylation of MLC and LIMK1 through the inhibition of RhoA/ROCK signaling. Overall, LOC441461 was discovered to play an oncogenic role in CRC cell growth and motility through RhoA/ROCK signaling. Our findings provide new insights into the regulation of lncRNAs and their application in the treatment of colon cancer

Lappaconitine sulfate induces apoptosis and G0/G1 phase cell cycle arrest by PI3K/AKT signaling pathway in human non-small cell lung cancer A549 cells

Lappaconitine sulfate (LS) has good solubility and bioavailability. We have previously studied the anti-proliferative activity of LS on colon cancer HT-29 cell, but its anti-proliferative activity and molecular mechanism on human non-small cell lung cancer A549 cells are still unclear. This study was to investigate the effects of LS on proliferation, cell cycle and apoptosis in human non-small cell lung cancer A549 cells, and its possible molecular mechanisms. Cell proliferation activity was measured by Cell Counting Kit-8 (CCK-8) and 5-Ethynyl-2'- deoxyuridine (EdU) cell proliferation kit. Cell cycle was detected by propidium iodide (PI) flow cytometry. Apoptosis was detected by Annexin-V-FITC/PI method. Western blot was used to detect cycle and apoptosis-related proteins expression. These results showed that the proliferation activity of LS was significantly decreased in A549 cells, showing a dose- and time-dependent manner (p < 0.05). LS could increase the proportion of G0/G1 phase cells and decrease the proportion of cells in S phase, showing obvious G0/G1 phase arrest. LS significantly inhibited the expression of p-PI3K/PI3K, p-AKT/AKT, Cyclin D1 and Bcl-2 proteins (p < 0.05), and increased the expression of p53, p21, Bax, caspase 3 and caspase 9 (p < 0.05). Moreover, PI3K inhibitor (LY294002) significantly decreased A549 cell viability rate induced by LS, abrogated the activation of p-PI3K/PI3K and p-AKT/AKT in the presence of LS. These results indicated that LS could block A549 cells in the G0/G1 phase, induce apoptosis, and inhibit cell proliferation through the PI3K/AKT signaling pathway.

Versatile role of curcumin and its derivatives in lung cancer therapy

Lung cancer is a main cause of death all over the world with a high incidence rate. Metastasis into neighboring and distant tissues as well as resistance of cancer cells to chemotherapy demand novel strategies in lung cancer therapy. Curcumin is a naturally occurring nutraceutical compound derived from Curcuma longa (turmeric) that has great pharmacological effects, such as anti-inflammatory, neuroprotective, and antidiabetic. The excellent antitumor activity of curcumin has led to its extensive application in the treatment of various cancers. In the present review, we describe the antitumor activity of curcumin against lung cancer. Curcumin affects different molecular pathways such as vascular endothelial growth factors, nuclear factor-κB (NF-κB), mammalian target of rapamycin, PI3/Akt, microRNAs, and long noncoding RNAs in treatment of lung cancer. Curcumin also can induce autophagy, apoptosis, and cell cycle arrest to reduce the viability and proliferation of lung cancer cells. Notably, curcumin supplementation sensitizes cancer cells to chemotherapy and enhances chemotherapy-mediated apoptosis. Curcumin can elevate the efficacy of radiotherapy in lung cancer therapy by targeting various signaling pathways, such as epidermal growth factor receptor and NF-κB. Curcumin-loaded nanocarriers enhance the bioavailability, cellular uptake, and antitumor activity of curcumin. The aforementioned effects are comprehensively discussed in the current review to further direct studies for applying curcumin in lung cancer therapy.