Chabamide induces cell cycle arrest and apoptosis by the Akt/MAPK pathway and inhibition of P-glycoprotein in K562/ADR cells

Epifriedelanol enhances adriamycin-induced cytotoxicity towards K562/ADM cells by down regulating of P-gp and MRP2

1. Multidrug resistance (MDR) is a critical issue during chemotherapy of cancers. Epifriedelanol (Epi) is the effective compounds from the Root Bark of Ulmus davidiana. This study aims to investigate the effect of Epi on MDR and its potential mechanism in the adriamycin (Adr)-resistant K562/ADM cells.2. The effect of Epi on MDR, P-glycoprotein (P-gp) and multidrug resistance-associated proteins (MRPs) were investigated in the adriamycin (Adr)-resistant K562/ADM cells. In addition, the alterations of nuclear receptor pregnane X receptor (PXR) and constitutive androstane receptor (CAR) mRNA expression levels in K562/ADM cells after Epi treatment were also examined.3. Epi significantly enhanced Adr-induced cytotoxicity towards K562/ADM cells. Combination of Epi and Adr can significantly reduce the 50% inhibitory concentration (IC₅₀) of K562/ADM cells to Adr. The reversal fold was 1.83 and 3.64 after treated with Epi at 10 and 20 μM, respectively. The intracellular accumulation of Adr was significant increased after exposure to Epi at 5-20 μM compared with the control group. Furthermore, Epi treatment significantly decreased the mRNA and protein expression of P-gp and MRP2 in K562/ADM cells.4. The present study demonstrated that Epi could enhance Adr-induced cytotoxicity towards K562/ADM cells accompanied by the down-regulation of P-gp and MRP2.

S-20, a steroidal saponin from the berries of black nightshade, exerts anti-multidrug resistance activity in K562/ADR cells through autophagic cell death and ERK activation

Multidrug resistance (MDR) is a major cause of chemotherapy failure. Adriamycin (ADR) has been widely used to treat cancer, however, as a substrate of the adenosine triphosphate binding cassette (ABC) transporter, it is easy to develop drug resistance during the treatment. Here, we demonstrated that steroidal saponin S-20 isolated from the berries of black nightshade has comparable cytotoxicity in ADR-sensitive and resistant K562 cell lines. Autophagy is generally considered to be a protective mechanism to mediate MDR during treatment. However, we found that S-20-induced cell death in K562/ADR is associated with autophagy. We further explored the underlying mechanisms and found that S-20 induces caspase-dependent apoptosis in ADR-sensitive and resistant K562 cell lines. Most importantly, S-20-induced autophagy activates the ERK pathway and then inhibits the expression of drug resistance protein, which is the main reason to overcome K562/ADR resistance, rather than apoptosis. Taken together, our findings emphasize that S-20 exerts anti-multidrug resistance activity in K562/ADR cells through autophagic cell death and ERK activation, which may be considered as an effective strategy.

Molecular insights on chemopreventive and anticancer potential of carvacrol: Implications from solid carcinomas

Globally, cancer is one of the deadliest diseases, estimated to cause 9.9 million deaths in 2020. Conventional cancer treatments commonly involve mono-chemotherapy or a combination of radiotherapy and mono-chemotherapy. However, the negative side effects of these approaches have been extensively reported and have prompted the search for new therapeutic drugs. Over the past few years, numerous dietary agents, medicinal plants, and their phytochemicals gained considerable therapeutic importance because of their anticancer, antiviral, anti-inflammatory, and antioxidant activities. Recent years have shown that essential oils possess therapeutic effects against numerous cancers. They are primarily used due to their lesser side effects than standard chemotherapeutic drugs. Carvacrol (CRV) is a phenolic monoterpenoid found in essential oils of oregano, thyme, pepperwort, wild bergamot, and other plants. Numerous anticancer reports of CRV substantiated that the main mechanistic action of CRV involves reduction in the viability of cancer cells and induction of apoptosis via both intrinsic and extrinsic pathways. CRV also obstructs the migration and invasion of cells leading to the suppressed proliferation rate. Furthermore, CRV mediates augmented ROS generation resulting in DNA damage and also halts the progression of cell cycle. Treatment of CRV modulates the expression of apoptotic proteins (Bax, Bad) and molecular targets of various signaling pathways (PI3K/AKT/mTOR, MAPKs, and Notch) in multiple solid carcinomas. Hence, this review aimed to acquire and disseminate the knowledge of chemopreventive and anticancer effects of CRV and the mechanisms of action already described for the compound against numerous cancers, including solid carcinomas, to guide future research. PRACTICAL APPLICATIONS: Development and formulation of phytocompound based anticancer drug agents to counteract the aftereffects of chemotherapeutic drugs is a propitious approach. CRV is a monoterpenoid consisting of a phenolic group obtained from the essential oils of oregano and thyme. These plants are being used as food flavoring spice and as fragrance ingredient in various cosmetic formulations. For the use of CRV as an efficient chemopreventive agent, different therapeutic interactions of CRV along with its targeted pathways and molecules, involved in the regulation of onset and progression of various types of solid carcinomas, need to be studied and explored thoroughly.

Characterization of Drug Resistance in Chronic Myeloid Leukemia Cells Based on Laser Tweezers Raman Spectroscopy

Multidrug resistance is highly associated with poor prognosis of chronic myeloid leukemia. This work aims to explore whether the laser tweezers Raman spectroscopy (LTRS) could be practical in separating adriamycin-resistant chronic myeloid leukemia cells K562/adriamycin from its parental cells K562, and to explore the potential mechanisms. Detection of LTRS initially reflected the spectral differences caused by chemoresistance including bands assigned to carbohydrates, amino acid, protein, lipids, and nucleic acid. In addition, principal components analysis as well as the classification and regression trees algorithms showed that the specificity and sensitivity were above 90%. Moreover, the band data-based classification and regression tree model and receiver operating characteristic curve further determined some important bands and band intensity ratios to be reliable indexes in discriminating K562 chemoresistance status. Finally, we highlighted three metabolism pathways correlated with chemoresistance. This work demonstrates that the label-free LTRS analysis combined with multivariate statistical analyses have great potential to be a novel analytical strategy at the single-cell level for rapid evaluation of the chemoresistance status of K562 cells.

Peppers: A "Hot" Natural Source for Antitumor Compounds

Piper, Capsicum, and Pimenta are the main genera of peppers consumed worldwide. The traditional use of peppers by either ancient civilizations or modern societies has raised interest in their biological applications, including cytotoxic and antiproliferative effects. Cellular responses upon treatment with isolated pepper-derived compounds involve mechanisms of cell death, especially through proapoptotic stimuli in tumorigenic cells. In this review, we highlight naturally occurring secondary metabolites of peppers with cytotoxic effects on cancer cell lines. Available mechanisms of cell death, as well as the development of analogues, are also discussed.

Alkaloids as Anticancer Agents: A Review of Chinese Patents in Recent 5 Years

BACKGROUND

In recent years, many novel alkaloids with anticancer activity have been found in China, and some of them are promising for developing as anticancer agents.

OBJECTIVE

This review aims to provide a comprehensive overview of the information about alkaloid anticancer agents disclosed in Chinese patents, and discusses their potential to be developed as anticancer drugs used clinically.

METHODS

Anticancer alkaloids disclosed in Chinese patents in recent 5 years were presented according to their mode of actions. Their study results published on PubMed, and SciDirect databases were presented.

RESULTS

More than one hundred anticancer alkaloids were disclosed in Chinese patents and their mode of action referred to arresting cell cycle, inhibiting protein kinases, affecting DNA synthesis and p53 expression, etc. Conclusion: Many newly found alkaloids displayed potent anticancer activity both in vitro and in vivo, and some of the anticancer alkaloids acted as protein kinase inhibitors or CDK inhibitors possess the potential for developing as novel anticancer agents.

Chemical profile, traditional uses, and biological activities of Piper chaba Hunter: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Piper chaba Hunter, called Chui Jhal or Choi Jhal, is commonly used as a culinary (spice) herb in India and Bangladesh. It exhibits numerous important biological activities and has been widely used in traditional medicine.

AIM OF THE STUDY

This review focuses on the chemical and pharmacological activities of a culinary ingredient P. chaba based on information extracted from the literature to highlight its use in traditional medicine.

METHODS

A literature search in known databases was conducted (till September 2019) for published articles using the relevant keywords.

RESULTS

Findings suggest that, to date, a number of important phytoconstituents such as dimeric alkaloids, and alkamides have been isolated from various parts of P. chaba. Extracts from P. chaba or derived compounds exhibit diverse biological activities, such as anti-microbial, anti-leishmanial, anti-malarial, anti-parasitic, cytotoxic/anticancer, adipogenic, hepato- and gastro-protective, anti-diabetic, analgesic, anti-diarrheal, depressive, anti-inflammatory, diuretic, anti-hypertensive, antipyretic, anti-ulcer, and immunomodulatory effect. Among the isolated compounds, chabamides, piperine, piplartine, retrofractamides A/B, methylenedioxyphenyl)-nona-2E,4E,8E-trienoic acid, n-butyl or n-pentyl amine, piperlonguminine, pipernonaline, dehydropipernonaline, N-isobutyl-(2E,4E)-octadecadienamide, and N-isobutyl-(2E,4E,14Z)-eicosatrienamide have documented important biological effects in various test systems.

CONCLUSIONS

Taken together, P. chaba may be a potential source of plant-based therapeutic lead compounds, which justify its uses in traditional medicine.

Anti-angiogenic and anti-proliferative effects of Benja-ummarit extract in rats with hepatocellular carcinoma

The herbal extract Benja-ummarit (BU) is a traditional Thai medicine with a putative cancer-suppressing effect. However, this effect has only been tested in vitro in human hepatocarcinoma cell lines. The present study determined the efficacy of a BU extract to treat hepatocellular carcinoma (HCC) in rats in vivo and established its anti-angiogenic and anti-proliferative properties. The BU extract was prepared in 95% ethanol and its composition determined using liquid chromatography-mass spectrometry. HCC was induced in Wistar rats by an injection of diethylnitrosamine (DEN), followed 2 weeks later by injections of thioacetamide (TAA) thrice weekly for 4 weeks. Following 2 months, the DEN-TAA-treated rats were divided into 6 groups that were treated orally for another 2 months with: i) No treatment; ii) vehicle; iii) 30 mg/kg sorafenib (SF); iv) 1 mg/kg BU; v) 10 mg/kg BU; or vi) 50 mg/kg BU. Liver samples were collected for gross morphological, histological, reverse transcription-quantitative PCR and western blot analyses, and serum samples were collected for liver function tests. The size and number of the cancer nodules were reduced ~10-fold in BU-treated HCC groups and ~14-fold in the SF-treated group compared with the HCC group. Furthermore, the serum parameters of liver damage were lower in BU-compared with SF-treated rats. These results indicate that while each of these formulations strongly reduce HCC expansion, BU extract results in less liver damage. Vascular endothelial growth factor expression was reduced significantly in the BU-and SF-treated HCC groups compared with the HCC group (P<0.05). BU extract antagonizes HCC growth in vivo potently through inhibiting tumor angiogenesis. BU, therefore, qualifies as a promising medical herb requiring further evaluation as a treatment of HCC.

[Role of protein kinase D1 in regulating the growth, apoptosis and drug sensitivity of oral squamous carcinoma cells]

OBJECTIVE

This study aimed to investigate the role of protein kinase D (PKD)1 in regulating the growth, apop-tosis, and drug sensitivity of the squamous carcinoma cell line SCC-25.

METHODS

The SCC-25 cell line was transfected with either the control-shRNA or PKD1-shRNA plasmids. The stable transfected cells were selected, and the efficiency of PKD1 knockdown was detected by Western blot. The growth and apoptosis of SCC-25 were analyzed with a cell counting kit-8 (CCK8) and flow cytometry. The 50% inhibitory concentrations (IC50) of paclitaxel in the control and PKD1 knockdown cell lines were detected by CCK-8. The expression levels of Bax, Bcl-2, and P-gp were detected by Western blot.

RESULTS

PKD1 was constitutively expressed and phosphorylated in various cancer cell lines. Inhibiting the expression of PKD1 in SCC-25 cells by RNA interference could inhibit the growth and promote the apoptosis of SCC-25 cells via downregulating Bcl-2 expression. Additionally, inhibiting PKD1 expression could downregulate the expression of P-gp, thereby decreasing both the IC50 and resistance index of paclitaxel.

CONCLUSIONS

PKD1 plays an important role in regulating the biobehavior of SCC-25. It is a potential therapeutic target for oral squamous carcinoma.

Formulation, Characterization And Evaluation Of Curcumin- Loaded PLGA- TPGS Nanoparticles For Liver Cancer Treatment

Background

Liver cancer is a major health problem facing mankind. Currently, the focus of research is to improve the treatment of liver cancer using a variety of treatment options such as providing chemotherapy drugs through nanocarriers.

Purpose

The aim of this study was to prepare a curcumin-loaded (PLGA/TPGS) NPs delivery system by the emulsification-solvent evaporation method in order to achieve synergistic antitumor activity against liver cancer.

Methods

Curcumin-loaded (PLGA/TPGS) NPs were prepared by the emulsification and solvent evaporation method. The physical and chemical characteristics of NPs such as size, morphology, and release profiles were discussed. In vitro and in vivo studies were carried out to evaluate its anti-tumor activity in target cells.

Results

Curcumin-loaded (PLGA/TPGS) NPs could be successfully internalized by HepG2 cells and play a synergistic role in inhibiting the growth of hepatocellular carcinoma cells. They exhibited high target organ accumulation, superior antitumor efficiency, and lower toxicity in vivo.

Conclusion

The present study indicates that the curcumin-loaded (PLGA/TPGS) NPs provide a promising platform for the treatment of liver cancer.

Solanine reverses multidrug resistance in human myelogenous leukemia K562/ADM cells by downregulating MRP1 expression

Multidrug resistance (MDR) in leukemia cells is a major obstacle to chemotherapeutic treatment. High expression and constitutive activation of multidrug resistance protein 1 (MRP1) has been associated with the development of resistance to anticancer drugs in a number of tumor types. The activity of c-Jun N-terminal kinase 1 (JNK1) is associated with the occurrence of MDR and MRP1 expression. The present study aimed to investigate the ability of solanine to resensitize the Adriamycin^® (ADR)-resistant human myelogenous leukemia cell line K562/ADM to ADR. Results of the Cell Counting Kit-8 assay demonstrated that solanine inhibited K562/ADM cell proliferation. K562/ADM cell sensitivity to ADR was increased following treatment with solanine, indicated by increased intracellular accumulation of ADR. Western blotting demonstrated that treatment with solanine led to reduced MRP1 protein expression, suggesting that solanine-induced ADR accumulation is due to the downregulation of MRP1 expression. Solanine-mediated MRP1 downregulation was observed to be dependent on the JNK signaling pathway. In conclusion, the results of the present study suggest that solanine reverses MDR in K562/ADM cells and may represent a novel therapeutic agent for the treatment of human myelogenous leukemia.

Carvacrol nanoemulsion evokes cell cycle arrest, apoptosis induction and autophagy inhibition in doxorubicin resistant-A549 cell line

Carvacrol is a monoterpenoid flavonoid found abundantly in thyme plants. Its physiochemical instability and partial solubility in water is the principal limitation for its industrial use. Hence, we made a carvacrol nanoemulsion (CANE) using ultrasonication method and characterized it by dynamic light scattering (DLS) technique which revealed a negative surface charge (-29.89 mV) with 99.1 nm average droplet size. CANE effectively induced apoptosis in doxorubicin-resistant A549 lung carcinoma cells (A549^DR) evident by the elevated expression of apoptotic proteins such as Bax, Cytochrome C, and Cleaved caspase 3 and 9. Also, CANE displayed cell senescence leading to cell cycle arrest by reducing CDK2, CDK4, CDK6, Cyclin E, Cyclin D1 and enhancing p21 protein expression. In addition, a potential role of CANE in the inhibition of autophagy was noted by evaluating the reduced conversion of LC-3 I to II. Beside this, a down-regulation of important autophagy markers ATG5 and ATG7 and upregulation of p62 were detected in response to CANE. We conclude that the synthesized CANE has potential to cause cell senescence, cell cycle arrest, autophagy inhibition and apoptosis in A549^DR cells and could be used as a potential candidate for lung cancer therapy.

Liposomal curcumin and its application in cancer

Curcumin (CUR) is a yellow polyphenolic compound derived from the plant turmeric. It is widely used to treat many types of diseases, including cancers such as those of lung, cervices, prostate, breast, bone and liver. However, its effectiveness has been limited due to poor aqueous solubility, low bioavailability and rapid metabolism and systemic elimination. To solve these problems, researchers have tried to explore novel drug delivery systems such as liposomes, solid dispersion, microemulsion, micelles, nanogels and dendrimers. Among these, liposomes have been the most extensively studied. Liposomal CUR formulation has greater growth inhibitory and pro-apoptotic effects on cancer cells. This review mainly focuses on the preparation of liposomes containing CUR and its use in cancer therapy.

Alkaloids from Piper nigrum Exhibit Antiinflammatory Activity via Activating the Nrf2/HO-1 Pathway

In the present study, ten alkaloids, namely chabamide (1), pellitorine (2), retrofractamide A (3), pyrroperine (4), isopiperolein B (5), piperamide C9:1 (8E) (6), 6,7-dehydrobrachyamide B (7), 4,5-dihydropiperine (8), dehydropipernonaline (9), and piperine (10), were isolated from the fruits of Piper nigrum. Among these, chabamide (1), pellitorine (2), retrofractamide A (3), isopiperolein B (5), and 6,7-dehydrobrachyamide B (7) exhibited significant inhibitory activity on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells, with IC₅₀ values of 6.8, 14.5, 30.2, 23.7, and 38.5 μM, respectively. Furthermore, compound 1 inhibited lipopolysaccharide-induced NO production in bone marrow-derived macrophages with IC₅₀ value of 9.5 μM. Consistent with NO inhibition, treatment of RAW264.7 cells with chabamide (1), pellitorine (2), and 6,7-dehydrobrachyamide B (7) suppressed expression of inducible NO synthase and cyclooxygenase-2. Chabamide (1), pellitorine (2), and 6,7-dehydrobrachyamide B (7) induced heme-oxygenase-1 expression at the transcriptional level. In addition, compound 1 induced the nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) and upregulated the expression of Nrf2 target genes, NAD(P)H:quinone oxidoreductase 1 and γ-glutamyl cysteine synthetase catalytic subunit, in a concentration-dependent manner in RAW264.7 cells. These findings suggest that chabamide (1) from P. nigrum exert antiinflammatory effects via the activation of the Nrf2/heme-oxygenase-1 pathway; hence, it might be a promising candidate for the treatment of inflammatory diseases. Copyright © 2017 John Wiley & Sons, Ltd.

A Survey of the Chemical Compounds of Piper spp. (Piperaceae) and Their Biological Activities

The genus Piper is one of the largest genera in the Piperaceae, with most species widely distributed globally, covering all continents. To date, many Piper species have been scientifically investigated for their chemical diversities and interesting broad spectrum of bioactivities, including central nervous system (CNS), pesticidal, antifungal and antibacterial effects. This review systematically summarizes the scaffolds of the alkaloids reported, the major chemicals isolated from Piper spp., and their biological activities. Besides the alkaloids, some neolignans with rearranged skeletons show structural diversities, while the chalcones, flavonoids and kava-pyrones have some potential activities. Herein, the sesquiterpenes and phenolic compounds from Piper species and their bioactivities are also surveyed.

Knockdown of HOXA10 reverses the multidrug resistance of human chronic mylogenous leukemia K562/ADM cells by downregulating P-gp and MRP-1

Multidrug resistance (MDR) of leukemia cells is a major obstacle in chemotherapeutic treatment. The high expression and constitutive activation of P-glycoprotein (P-gp) and multidrug resistance protein-1 (MRP-1) have been reported to play a vital role in enhancing cell resistance to anticancer drugs in many tumors. The present study aimed to investigate the reversal of MDR by silencing homeobox A10 (HOXA10) in adriamycin (ADR)-resistant human chronic myelogenous leukemia (CML) K562/ADM cells by modulating the expression of P-gp and MRP-1. K562/ADM cells were stably transfected with HOXA10-targeted short hairpin RNA (shRNA). The results of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis showed that the mRNA and protein expression of HOXA10 was markedly suppressed following transfection with a shRNA-containing vector. The sensitivity of the K562/ADM cells to ADR was enhanced by the silencing of HOXA10, due to the increased intracellular accumulation of ADR. The accumulation of ADR induced by the silencing of HOXA10 may be due to the downregulation of P-gp and MRP-1. Western blot analysis revealed that downregulating HOXA10 inhibited the protein expression of P-gp and MRP-1. Taken together, these results suggest that knockdown of HOXA10 combats resistance and that HOXA10 is a potential target for resistant human CML.

Potential anti-MDR agents based on the podophyllotoxin scaffold: synthesis and antiproliferative activity evaluation against chronic myeloid leukemia cells by activating MAPK signaling pathways

Compound 9k exhibited excellent cytotoxicity, induced apoptosis and G2/M cell cycle arrest, downregulated Pgp expression and up-regulated the expression of p-ERK1/2, p-JNK and p-p38 in K562/ADR cells.