Abstract
Different phytochemicals from various plant species exhibit promising medicinal properties against cancer. Juniperus phoenicea is a plant species that has been found to present medicinal properties. Herein, crude extract and fractions of J. phoenicea were examined to determine its anticancer properties against several cancer cells. The active fraction was chosen to assess its activity on cell cycle progression and apoptosis induction by annexin and propidium iodide (PI) biomarkers. Further, phytochemical screening for possible contents of active fraction using gas chromatography–mass spectrometry (GC-MS) analysis was conducted. It was demonstrated that cell proliferation was suppressed, and the MCF-7 cell line was the most sensitive to J. phoenicea chloroform fraction (JPCF), with the IC50 values of 24.5 μg/mL. The anti-proliferation activity of JPCF in MCF-7 cells was linked to the aggregation of cells in the G1 phase, increases in early and late apoptosis as well as necrotic cell death. Contents analysis of JPCF using GC-MS analysis identified 3-methyl-5-(2′,6′,6′-trimethylcyclohex-1′-enyl)-1-penten-3-ol (16.5%), methyl 8-oxooctanoate (15.61%), cubenol (13.48%), and 7-oxabicyclo [2.2.1] heptane (12.14%) as major constituents. Our present study provides clear evidence that J. phoenicea can inhibit cell proliferation, trigger cell cycle arrest, and induce apoptosis in tested cancer cells.
1 Introduction
Cancer continues to be a significant global public health risk factor, and cancer diagnoses are presumed to increase to 23.6 million new cases per year by 2030 [1]. Despite the progressive advance in conventional cancer treatments, medicinal plants with natural origins still offer promising options and have been recognized for their therapeutic effects with fewer adverse effects [2]. Juniperus (Family: Cupressaceae) is a genus of approximately 75 species of evergreen trees that are distributed throughout different regions of the world [3,4]. Juniperus species are well known as local remedies for several diseases. In Saudi Arabia, these species are commonly used to treat tuberculosis and jaundice [5]. Additionally, several species of this plant are used to treat bronchitis, hemorrhoids, and cold cough in Turkey [6]. Moreover, several recent studies have reported different pharmacological activities of Juniperus essential oil and extracts which include cytotoxic, antimicrobial, hypoglycemic, and anti-inflammatory activities [4,7,8,9]. Among Juniperus species, Juniperus phoenicea, or “Arar” (local name), is a shrub that can grow up to eight meters tall and is widely distributed in southern and Mediterranean regions of Saudi Arabia [10]. In folk medicine, the leaves of J. phoenicea species are used to treat several ailments, including bronchopulmonary diseases, diabetes, and as a diuretic [11,12]. The antioxidant properties, antibacterial, and hepatoprotective effects of J. phoenicea have also been reported [13,14]. Numerous studies have revealed that J. phoenicea grown in different geographical regions are capable of reducing the proliferation of different cancer cells [15,16,17,18]. In this study, we have reported the cytotoxicity of J. phoenicea grown in Saudi Arabia against human lung, breast, and liver cancer cells as well as its chemical profile using gas chromatography–mass spectrometry (GC-MS). To the best of our knowledge, the current study is the first to report that J. phoenicea can induce cell cycle arrest and apoptosis induction in MCF-7 cancer cells.
2 Materials and methods
2.1 Plant collection and authentication
Fresh aerial parts of J. phoenicea were collected from Al-Madinah Al-Munawara, Saudi Arabia, in March, 2019. The plant material was authenticated by Professor Sami Zalat, Biology Department, College of Science, Taibah University, Saudi Arabia.
2.2 Crude extracts and fractions preparation
The aerial parts were thoroughly washed with water, kept in the dark for 15 days, and then powdered. Three hundred grams of powdered plant material was then mixed with 1,500 mL ethanol–water (70/30 v/v) for 48 h using a Soxhlet apparatus. Next, the blend was centrifuged at 2,500 × g, and the collected supernatant was concentrated under reduced pressure in a rotary evaporator. The hydroethanolic extract (crude extract) was then fractionated by different polarity solvents including n-hexane (n-Hex) chloroform (CHCl3) and methanol (MeOH), and the residue was kept at –20°C for future use. The dry weight of each fraction was prepared at 20 mg/mL with DMSO cell culture grade.
2.3 Cell culture
Human lung (A549), breast (MCF-7), and liver (HepG2) cancer cells were obtained from German Collection of Microorganisms and Cell Cultures (Leibniz Institute DSMZ, Braunschweig, Germany). Cells were maintained at 37°C in a humidified CO2 incubator and were cultivated in DMEM medium (Gibco, US) supplemented with an FBS (10% final concentration) and 1% penicillin and streptomycin. Cells were subcultured when they reach 70% confluency and passage number of 25–30 was maintained for bioassay.
2.4 Cell viability (MTT assay)
MTT assay was used to assess the cell viability according to previous protocol [19]. Concisely, the cells were seeded in 24-well plates at a density of 1 × 105 cells/well. Approximately 24 h after incubation, the cells were treated with a range of extract concentrations (10, 25, 50, 100, and 200 μg/mL), doxorubicin (positive control), and DMSO as a vehicle while untreated cells served as a negative control. After 48 h of incubation, 100 μL of MTT solution was added to each well; then, the plate continued to incubate in the CO2 incubator for 4 h. Isopropanol–HCl solution (1,000 μL) was incorporated into each well and mixed thoroughly to dissolve the formazan product, which was measured using a microplate reader at 570 nm wavelength.
2.5 Cell cycle analysis
The cell phase distribution was performed according to the protocol outlined in [20,21] with slight alteration. MCF-7 cells were plated in 6-well culture plates at a density of 2 × 105 cells/well. Adhered cells were serum-starved in 2% FBS for overnight. The cells were then washed, replaced with complete media, and exposed to the half maximal inhibitory concentration (IC50) of J. phoenicea chloroform fraction (JPCF) for 24 h, while untreated cells served as a control. At the end of treatment, the cells were harvested, and the cell pellet was washed twice with ice-cold PBS and fixed in ice-cold absolute ethanol at −20°C for 4 h to overnight. The cells were then centrifuged, and the cell pellet was resuspended and incubated with RNaseA (100 µg/mL, 50 µL) for 15 min. Subsequently, cells were stained with propidium iodide (PI) (0.5 mL, 50 µg/ml) for 30 min. The cell cycle stage was analyzed using a FACS flow cytometer (Cytomics FC 500; Beckman Coulter, Brea, CA, USA).
2.6 FITC annexin V/PI apoptosis detection
Apoptotic cells were detected using a FITC Annexin V Apoptosis Detection Kit ((BioLegend, CA, USA), according to the manufacturer’s instructions. Briefly, 24 h after treatment with JPCF, floating and adherent cells were collected from three wells and washed with cold PBS. The cell pellet was resuspended in 1× binding buffer (1 × 106 cells/mL). The cells were then stained with 5 µL of FITC Annexin V and 5 µL PI and incubated for 15 min in the dark. Later, 400 µL of binding buffer was added, and cells were examined immediately after staining (within an hour) using a FACScan flow cytometer (Cytomics FC 500; Beckman Coulter, Brea, CA, USA).
2.7 GC-MS analysis
The phytoconstituents of JPCF were determined using a Perkin Elmer Clarus 600 GC-MS (PerkinElmer, Inc., Waltham, MA, USA) according to ref. [19]. In brief, JPCF aliquot was injected into the Elite-5MS column (30 m, 0.25 µm thickness, 0.25 µm internal diameter). The oven temperature was programmed to start at 40°C, held for 120 s, then increased to 200°C at a rate of 5°C min−1 and held for 120 s. From 200°C, the temperature increased to 300°C at 5°C min−1 and held for 2 min. The Adams [22] and Wiley GC-MS [23] compounds mass spectral libraries were used to compare similar mass spectra found for JPCF constituents. The characterizations of compounds were performed by comparing the RT (retention time) with genuine reference standards under the same above-indicated conditions [24].
2.8 Statistical analysis
OriginPro 8.5 software was used to perform statistical analysis. All data were reported as mean ± SD of three experiments and were analyzed with unpaired t-tests. Differences are considered as statistically significant if p < 0.05.
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Ethical approval: The conducted research is not related to either human or animal use.
3 Results
3.1 Cytotoxicity of J. phoenicea against different cancer cell lines
The crude and three fractions of J. phoenicea were screened for their potential cytotoxic activity. MTT assay results indicated that J. phoenicea crude extract and fractions suppressed the proliferation of all three examined cancer cell lines in a dependent manner with the JPCF showing promising activity (Figure 1). The cytotoxic activity of J. phoenicea fractions in terms of IC50 values is listed in (Table 1). Our results indicated that MCF-7 was most sensitive to JPCF with IC50 of 24.5 µg/mL in comparison to other tested cells (Table 1). Therefore, it was chosen to complete further experiments.
Antiproliferative effect of JPCF on A549, HepG2, and MCF-7. Cells were treated with J. phoenicea chloroform fraction (JPCF) at different concentrations for 48 h followed by the measurement of cell proliferation by MTT assay. Data represent as % of cell survival.
IC50 values of the J. phoenicea crude extract and various fractions against lung, liver, and breast cancer cells
| Cell type | IC50 values (μg/mL) | ||||
|---|---|---|---|---|---|
| Crude | n-Hex | CHCl3 | MeOH | Doxorubicin | |
| A549 (lung) | 146.2 ± 1.5 | 80 ± 1.2 | 34.2 ± 0.5 | 186.1 ± 1.8 | 1.2 ± 0.2 |
| HepG2 (liver) | 98.2 ± 0.9 | 76.4 ± 1.1 | 57.6 ± 0.9 | 160.4 ± 0.9 | 1.1 ± 0.3 |
| MCF-7 (breast) | 65.4 ± 0.5 | 55.1 ± 0.6 | 24.5 ± 0.5 | 130.4 ± 0.5 | 1.3 ± 0.4 |
3.2 JPCF induces G1 cell cycle arrest
Next, we evaluated the influence of JPCF on the cell cycle of MCF-7 cells using flow cytometry. Cell cycle analysis indicated that IC50 induced G1 phase cell cycle arrest (Figure 2). JPCF indicated a significant increase in the proportions of G1 phase (increased from 59 ± 0.4% to 75.6 ± 0.4%) and a reduction in the proportion of S and G2M phases (decreased by approximately 9 and 8%, respectively) compared with corresponding proportions in control cells (Figure 2).
Chloroform fraction of J. phoenicea induces G1 cell cycle arrest in MCF-7 cells. MCF-7 treated cells with the test fraction at IC50 for 24 h and were then stained with PI. Representative histogram that was obtained using a flow cytometer where quantitation was obtained from (a). *p ≤ 0.05, **p ≤ 0.01, or ***p ≤ 0.001.
3.3 JPCF induces apoptosis of MCF-7 cells
Double staining with annexin V-FITC and PI dyes was performed to recognize cells undergoing apoptosis events using a flow cytometer. As shown in (Figure 3), JPCF exhibited apoptotic induction at IC50 concentration. The early apoptosis cell population increased from 2.1 ± 0.3% to 13.1 ± 0.5% (*p ≤ 0.05), while the late apoptosis cell percentage increased from 2.3 ± 0.2% to 21.5 ± 0.5% (**p ≤ 0.01). In addition, a remarkable increase in the number of necrotic cells was also observed (Figure 3). Our flow cytometric data suggest that JPCF mediated inhibition of MCF-7 cancer cells through apoptosis as well as necrosis induction.
Induction of apoptosis and necrosis in MCF-7 cells by J. phoenicea chloroform fraction. MCF-7 cells were treated with the test fraction at IC50 for 24 h, then stained with FITC-Annexin V/PI. Dot Plots of JPCF-treated and untreated MCF-7 cells obtained using flow cytometer where a1 = necrosis, a2 = late apoptosis, a3 = viable, and a4 = early apoptosis. The percentage (%) of cell distribution. *p ≤ 0.05, **p ≤ 0.01.
3.4 Chemical composition of the JPCF
Since JPCF was the most active fraction, it was profiled using GC-MS analysis (Figure 4). The chemical content, retention times, and area percentages of JPCF are displayed in Table 2 according to their elution on the HP Innowax column. GC-MS analysis identified approximately 19 phytoconstituents. The most abundant constituent was 3-methyl-5-(2′,6′,6′-trimethylcyclohex-1′-enyl)-1-penten-3-ol (16.5%), methyl 8-oxooctanoate (15.61%), cubenol (13.48%), and 7-oxabicyclo [2.2.1] heptane (12.14%). The remaining compounds in JPCF are listed in Table 2.
GC-MS chromatogram and chemical structures of some constituents from JPCF.
GC-MS analysis of JPCF
| Compound name | Chemical formula | MW (g/mol) | RT (min) | Area % |
|---|---|---|---|---|
| trans-Caryophyllene | C15H24 | 204.35 | 10.70 | 0.600 |
| alpha-Humulene | C15H24 | 204.35 | 11.09 | 1.430 |
| delta-Cadinene | C15H24 | 204.35 | 11.65 | 2.530 |
| 1s-cis-calamenene | C15H22 | 202.33 | 11.71 | 3.640 |
| beta-Cedrene | C15H24 | 204.36 | 11.82 | 0.700 |
| Nerolidol | C15H26O | 222.37 | 11.99 | 0.640 |
| Caryophyllene oxide | C15H24O | 220.35 | 12.36 | 0.510 |
| Humuladienone | C15H24O | 220.35 | 12.62 | 0.330 |
| Cubenol | C15H26O | 222.37 | 12.74 | 13.480 |
| tau-Muurolol | C15H26O | 222.37 | 12.89 | 3.320 |
| 3-Ethenyl-3-methyl-2-(1-methyethenyl)-6-(1-methyethyl)-cyclohexanol | C15H26O | 222.37 | 13.22 | 1.210 |
| 7-Acetyl-2-hydroxy-2-methyl-5-isopropylbicyclo[4.3.0]nonane | C15H26O2 | 238.37 | 13.68 | 2.150 |
| Citronellyl acetate | C12H22O2 | 198.3 | 14.19 | 0.600 |
| Ethyl ester of heptadecanoic acid | C19H38O2 | 298.5 | 14.53 | 1.140 |
| Methyl 8-oxooctanoate | C9H16O3 | 172.22 | 15.18 | 15.610 |
| Ethyl ester of hexadecanoic acid | C18H36O2 | 284.5 | 15.28 | 3.480 |
| 3,7,11,15-Tetramethyl-2-hexadecen-1-ol | C20H40O | 296.5 | 16.08 | 1.360 |
| 3-Methyl-5-(2′,6′,6′-trimethylcyclohex-1′-enyl)-1-penten-3-ol | C15H26O | 222.37 | 17.26 | 16.500 |
| 7-Oxabicyclo[2.2.1]heptane | C6H10O | 98.14 | 16.84 | 12.140 |
4 Discussion
The use of medicinal plants has highlighted the value of plants as a valuable source of therapeutic agents. Several antitumor agents from natural sources are broadly used in chemotherapy. Both traditional and current medicines have been recommended as promising methodologies to discover and bring new plant-derived compounds to market [25,26]. Therefore, many studies focus on plants as they have been used to prevent several chronic diseases, including cancer. In this study, we have shown for the first time that Saudi Arabian J. phoenicea exerts anticancer activities through cell cycle arrest and apoptosis induction.
The cytotoxicity of the Juniperus genus against different cancer types has been reported in several studies [27,28,29]. Various reports on J. phoenicea species grown in different regions confirm that they also display strong antiproliferative activities. In line with our obtained results, Maamoun et al. (2016) found that crude extract of Egyptian J. phoenicea leaves exerted strong cytotoxicity against various carcinoma cell lines [18]. Additionally, various fractions from Libyan J. phoenicea also displayed a potent effect on breast MCF-7 cancer cells [15,30], with a slight difference in IC50 values. However, according to our survey, this is the first report that examined the effect of J. phoenicea extracts on the cell cycle and cell death mode on MCF-7 cells.
In the same manner, a recent study reported on the strong cytotoxic activity of Algerian J. phoenicea essentials oils against two human breast adenocarcinoma (MCF-7 and T-47D) cells. However, the IC50 values were also different from what we found here; this result could be due to the different components in the same species as a consequence of different geographical origins and environmental factors [31,32].
According to criteria defined by the American National Cancer Institute regarding the cytotoxic activity of crude plant extracts (IC50 < 30 μg/mL) [33], JPCF was the most efficient fraction of all fractions from J. phoenicea (IC50 = 24.5 μg/mL). Therefore, it was selected to assess its activity on the cell cycle and apoptosis induction at the corresponding IC50 value.
It is well known that cell proliferation is controlled by a highly regulated cell cycle process, and the dysregulation of the cell cycle is one feature of cancer cells [34,35]. Natural compounds that can disrupt cell cycle progression are considered among the most commonly used anticancer drugs [36]. Hence, the effect of JPCF on cell cycle progression was explored. Our findings showed that JPCF caused a significant cell cycle arrest in the G0/G1 phase suggesting the involvement of JPCF constituents in mediating this activity. Some studies have described the prevention of cell cycle progression for compounds and plant extracts belonging to the genus Juniperus [29,37]. Apoptosis evasion is also one of the most important characteristics of cancer cells, and targeting this pathway is a critical therapeutic approach to cancer therapy [38,39]. Therefore, we examined the capacity of JPCF to initiate apoptosis using the FTIC-Annexin V/PI method. In this method, early apoptotic, late apoptotic/necrotic, and dead cells are differentiated and quantitatively analyzed via flow cytometry [40]. The present study showed that JPCF mediated a significant antiproliferative effect that was associated with apoptosis and necrosis cell death. In fact, it has been noted that several conventional chemotherapeutic agents exerted various forms of cell death, the most important of which are apoptosis and necrosis [41]. Additionally, several constituents and extracts from the Juniperus genus were found to mediate apoptosis in different cancer cells [42,43,44,45]. GC-MS is one method for characterizing the constituents in plant extracts. In this study, we have documented different constituents found in JPCF. In partial agreement with what we found in this study, Keskes et al. reported the presence of alpha-humulene (16.9%) and alpha-cubebene (9.7%) in the hexane extract of Tunisian J. phoenicea [46]. In contrast, the obtained GC-MS profile was varied from those reported for Egyptian J. phoenicea [18]. These differences could result from several factors such as geographical location, the plant part used, and the extraction methodologies and solvents used.
The resulting GC-MS analysis showed the presence of some compounds in JPCF that were previously known to exert antiproliferative activities. Delta-cadinene was found among these compounds and is one of the most widely occurring plant sesquiterpenes. Hui et al. reported that delta-cadinene had potent anticancer effects on OVCAR-3 (human ovarian cancer cells) through the induction of apoptosis, sub-G1-phase cell cycle arrest, and caspase activation [47]. The cytotoxic activity of cubenol, which represents 13.48% of all constituents of JPCF, also exhibited strong cytotoxicity against the retinoblastoma cancer cell line (NCIH187) [48]. Alpha-humulene (β-caryophyllene), a sesquiterpene that has anticarcinogenic effect and is widely distributed in different plant species [49], was also detected in our GC-MS data. Taken together, the presence of these components in JPCF may synergistically exert the anticancer potential of J. phoenicea reported in this study.
5 Conclusions
This study displayed that the extracts obtained from J. phoenicea species have antiproliferative effects against lung, liver, and breast cancer cells. In particular, we found that JPCF exerted cell death on MCF-7 cells through blocking the cell cycle in the G1 phase. Apoptotic and necrotic effects of JPCF on MCF-7 cancer cells were also observed. In parallel, GC-MS analysis revealed the presence of some anticancer compounds such as cubenol, delta-cadinene, and alpha-humulene. Based on this phytochemical depiction, we can conclude that some of these compounds, along with the remaining constituents of JPCF, are capable of initiating cell death in human cancer cells. These outcomes propose that JPCF may be an excellent source of active phytochemicals for cancer treatment. Future studies should aim to explore the anticancer activity of each compound, its detail mechanism, and its synergistic effects.
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Funding information: This research was funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University through the Fast-track Research Funding Program.
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Author contributions: Conceptualization, A. S. A; methodology, I. O. B., H. M. D., F. A. N. O. M. N., and M. Z.; software, W. A. A. and A. A.; validation, R. N. H. and A. A. M.; data curation, writing – original draft preparation, F. A. N; writing – review and editing, A. A. A., F. A. N.; funding acquisition, A. A. A. All authors have read and agreed to the published version of the manuscript.
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Conflict of interest: The authors declare no conflict of interest.
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Data availability statement: All the data related to these findings are included in the MS.
References
[1] Bray F, Ferlay J, Soerjomataram I, Siegel RL, Torre LA, Jemal A, et al. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2018;68(6):394–424.10.3322/caac.21492Search in Google Scholar PubMed
[2] Choudhari AS, Mandave PC, Deshpande M, Ranjekar P, Prakash O. Phytochemicals in cancer treatment: from preclinical studies to clinical practice. Front pharmacol. 2020;10:1614.10.3389/fphar.2019.01614Search in Google Scholar PubMed PubMed Central
[3] Adams RP. Junipers of the world: the genus Juniperus. Bloomington: Trafford Publishing; 2014.Search in Google Scholar
[4] Raina R, Verma PK, Peshin R, Kour H. Potential of Juniperus communis L as a nutraceutical in human and veterinary medicine. Heliyon. 2019;5(8):e02376.10.1016/j.heliyon.2019.e02376Search in Google Scholar PubMed PubMed Central
[5] Muhammad I, Mossa J, El‐Feraly F. Antibacterial diterpenes from the leaves and seeds of Juniperus excelsa M. Bieb. Phytother Res. 1992;6(5):261–4.10.1002/ptr.2650060508Search in Google Scholar
[6] Topçu G, Gören AC, Bilsel G, Bilsel M, Çakmak O, Schilling J, et al. Cytotoxic activity and essential oil composition of leaves and berries of Juniperus excelsa. Pharm Biol. 2005;43(2):125–8.10.1080/13880200590919429Search in Google Scholar
[7] Alkhedaide A, Abdo Nassan M, Ahmed Ismail T, Soliman MM, Hassan ME, Hassan AH, et al. Hypoglycemic and antioxidant effect of Juniperus procera extract on rats with streptozotocin-induced diabetes. Pathophysiology. 2019;26(3):361–8.10.1016/j.pathophys.2019.11.001Search in Google Scholar PubMed
[8] Darwish RS, Hammoda HM, Ghareeb DA, Abdelhamid AS, Bellah EM, Harraz FM, et al. Efficacy-directed discrimination of the essential oils of three Juniperus species based on their in vitro antimicrobial and anti-inflammatory activities. J Ethnopharmacol. 2020;259:112971.10.1016/j.jep.2020.112971Search in Google Scholar PubMed
[9] Yaglioglu AS, Eser F. Screening of some Juniperus extracts for the phenolic compounds and their antiproliferative activities. S Afr J Bot. 2017;113:29–33.10.1016/j.sajb.2017.07.005Search in Google Scholar
[10] Chaudhary SA. Flora of the Kingdom of Saudi Arabia, illustrated vol 1. Ministry of Agriculture and Water, National Herbarium; 1999.Search in Google Scholar
[11] Allali H, Benmehdi H, Dib M, Tabti B, Ghalem S, Benabadji N. Phytotherapy of diabetes in west Algeria. Asian J Chem. 2008;20(4):2701.Search in Google Scholar
[12] Amer M, Wasif M, Abo-Aytta A, Gabr F. Chemical and biological evaluation of Juniperus phoenicea as a hypoglycaemic agent. Zagazig J Agric Res. 1995;21(4):1077–91.Search in Google Scholar
[13] Elmhdwi F, Attitalla H, Khan A. Evaluation of antibacterial activity and antioxidant potential of different extracts from the leaves of Juniperus phoenicea. J Plant Pathol Microb. 2015;6(9):300.10.4172/2157-7471.1000300Search in Google Scholar
[14] Laouar A, Klibet F, Bourogaa E, Benamara A, Boumendjel A, Chefrour A, et al. Potential antioxidant properties and hepatoprotective effects of Juniperus phoenicea berries against CCl4 induced hepatic damage in rats. Asian Pac J Trop med. 2017;10(3):263–9.10.1016/j.apjtm.2017.03.005Search in Google Scholar PubMed
[15] Al Groshi A, Evans AR, Ismail FM, Nahar L, Sarker SD. Cytotoxicity of libyan Juniperus phoenicea against human cancer cell lines A549, EJ138, HepG2 and MCF7. Pharm Sci. 2018;24(1):3–7.10.15171/PS.2018.02Search in Google Scholar
[16] Barrero AF, Quı́lez del Moral JF, Herrador MM, Akssira M, Bennamara A, Akkad S, et al. Oxygenated diterpenes and other constituents from moroccan Juniperus phoenicea and Juniperus thurifera var. africana. Phytochemistry. 2004;65(17):2507–15.10.1016/j.phytochem.2004.07.021Search in Google Scholar PubMed
[17] El-Sawi SA, Motawae HM, Ali AM. Chemical composition, cytotoxic activity and antimicrobial activity of essential oils of leaves and berries of Juniperus phoenicea L. grown in Egypt. AJTCAM. 2007;4(4):417–26.10.4314/ajtcam.v4i4.31236Search in Google Scholar PubMed PubMed Central
[18] Maamoun M, El-sawi SA, Motawae HM, Sleem MA, El-shabrawy AO, Usama HW, et al. Antiproliferative effect of extracts and flavonoids of Juniperus phoenicea L. growing in Egypt. Mintage J Pharm Med Sci. 2016;5(2):1–7.Search in Google Scholar
[19] Al-Zharani M, Nasr FA, Abutaha N, Alqahtani AS, Noman OM, Mubarak M, et al. Apoptotic induction and anti-migratory effects of Rhazya Stricta fruit extracts on a human breast cancer cell line. Molecules. 2019;24(21):3968.10.3390/molecules24213968Search in Google Scholar PubMed PubMed Central
[20] Alqahtani AS, Nasr FA, Noman OM, Farooq M, Alhawassi T, Qamar W, et al. Cytotoxic evaluation and anti-angiogenic effects of two furano-sesquiterpenoids from Commiphora myrrh resin. Molecules. 2020;25(6):1318.10.3390/molecules25061318Search in Google Scholar PubMed PubMed Central
[21] Khurana L, ElGindi M, Tilstam PV, Pantouris G. Elucidating the role of an immunomodulatory protein in cancer: from protein expression to functional characterization. Methods Enzymol. 2019;629:307–60.10.1016/bs.mie.2019.05.053Search in Google Scholar PubMed
[22] Adams RP. Identification of essential oil components by gas chromatography/mass spectrometry, vol 456. Carol Stream, IL: Allured publishing corporation; 2007.Search in Google Scholar
[23] McLafferty FW, Stauffer DB. Wiley/NBS registry mass spectral data, vol 1. New York: Wiley; 1989.Search in Google Scholar
[24] Curvers J, Rijks J, Cramers C, Knauss K, Larson P. Temperature programmed retention indices: calculation from isothermal data. Part 1: theory. J High Resolut Chromatogr. 1985;8(9):607–10.10.1002/jhrc.1240080926Search in Google Scholar
[25] Fridlender M, Kapulnik Y, Koltai H. Plant derived substances with anti-cancer activity: from folklore to practice. Front Plant Sci. 2015;6:799.10.3389/fpls.2015.00799Search in Google Scholar PubMed PubMed Central
[26] Newman DJ, Cragg GM. Natural products as sources of new drugs from 1981 to 2014. J Nat Prod. 2016;79(3):629–61.10.1021/acs.jnatprod.5b01055Search in Google Scholar PubMed
[27] Ben Mrid R, Bouchmaa N, Bouargalne Y, Ramdan B, Karrouchi K, Kabach I, et al. Phytochemical characterization, antioxidant and in vitro cytotoxic activity evaluation of Juniperus oxycedrus Subsp. oxycedrus needles and berries. Molecules. 2019;24(3):502.10.3390/molecules24030502Search in Google Scholar PubMed PubMed Central
[28] Rafieian-kopaei M, Suleimani dehkordi I, Ghanadian M, Shokrollahi A, Aghaei M, Syed Majid A, et al. Bioactivity-guided isolation of new antiproliferative compounds from Juniperus foetidissima willd. Nat Prod Res. 2016;30(17):1927–33.10.1080/14786419.2015.1101106Search in Google Scholar PubMed
[29] Vasilijević B, Knežević-Vukčević J, Mitić-Ćulafić D, Orčić D, Francišković M, Srdic-Rajic T, et al. Chemical characterization, antioxidant, genotoxic and in vitro cytotoxic activity assessment of Juniperus communis var. saxatilis. Food Chem Toxicol. 2018;112:118–25.10.1016/j.fct.2017.12.044Search in Google Scholar PubMed
[30] Aljaiyash A, Gonaid MH, Islam M, Chaouch A. Antibacterial and cytotoxic activities of some Libyan medicinal plants. J Nat Prod Plant Resour. 2014;4(2):43–51.Search in Google Scholar
[31] McGhie TK, Hunt M, Barnett LE. Cultivar and growing region determine the antioxidant polyphenolic concentration and composition of apples grown in New Zealand. J Agric Food Chem. 2005;53(8):3065–70.10.1021/jf047832rSearch in Google Scholar PubMed
[32] Zhang Y, Lan M, Lü JP, Li JF, Zhang KY, Zhi H, et al. Antioxidant, anti‐inflammatory and cytotoxic activities of polyphenols extracted from chroogomphus rutilus. Chem Biodivers. 2020;17(1):e1900479.10.1002/cbdv.201900479Search in Google Scholar PubMed
[33] Itharat A, Houghton PJ, Eno-Amooquaye E, Burke PJ, Sampson JH, Raman A. In vitro cytotoxic activity of Thai medicinal plants used traditionally to treat cancer. J Ethnopharmacol. 2004;90(1):33–8.10.1016/j.jep.2003.09.014Search in Google Scholar PubMed
[34] Otto T, Sicinski P. Cell cycle proteins as promising targets in cancer therapy. Nat Rev Cancer. 2017;17(2):93–115.10.1038/nrc.2016.138Search in Google Scholar PubMed PubMed Central
[35] Vermeulen K, Van Bockstaele DR, Berneman ZN. The cell cycle: a review of regulation, deregulation and therapeutic targets in cancer. Cell Proliferat. 2003;36(3):131–49.10.1046/j.1365-2184.2003.00266.xSearch in Google Scholar PubMed PubMed Central
[36] Paier CR, Maranhão SS, Carneiro TR, Lima LM, Rocha DD, Santos RD, et al. Natural products as new antimitotic compounds for anticancer drug development. Clinics (Sao Paulo, Braz). 2018;73(suppl 1):e813s.10.6061/clinics/2018/e813sSearch in Google Scholar PubMed PubMed Central
[37] De Marino S, Cattaneo F, Festa C, Zollo F, Iaccio A, Ammendola R, et al. Imbricatolic acid from Juniperus communis L. prevents cell cycle progression in CaLu-6 cells. Planta Medica. 2011;77(16):1822–8.10.1055/s-0030-1271104Search in Google Scholar PubMed
[38] Hanahan D, Weinberg RA. The hallmarks of cancer. Cell. 2000;100(1):57–70.10.1093/med/9780199656103.003.0001Search in Google Scholar
[39] Ghobrial IM, Witzig TE, Adjei AA. Targeting apoptosis pathways in cancer therapy. CA Cancer J Clin. 2005;55(3):178–94.10.3322/canjclin.55.3.178Search in Google Scholar PubMed
[40] Wlodkowic D, Skommer J, Darzynkiewicz Z. Flow cytometry-based apoptosis detection. Methods Mol Biol (Clifton, NJ). 2009;559:19–32.10.1007/978-1-60327-017-5_2Search in Google Scholar PubMed PubMed Central
[41] Ricci MS, Zong W-X. Chemotherapeutic approaches for targeting cell death pathways. Oncologist. 2006;11(4):342–57.10.1634/theoncologist.11-4-342Search in Google Scholar PubMed PubMed Central
[42] Muto N, Tomokuni T, Haramoto M, Tatemoto H, Nakanishi T, Inatomi Y, et al. Isolation of apoptosis-and differentiation-inducing substances toward human promyelocytic leukemia HL-60 cells from leaves of Juniperus taxifolia. Biosci Biotechnol Biochem. 2008;72(2):477–84.10.1271/bbb.70570Search in Google Scholar PubMed
[43] Kwon HJ, Lee EW, Hong YK, Yun HJ, Kim BW. Widdrol from Juniperus chinensis induces apoptosis in human colon adenocarcinoma HT29 cells. Biotechnol Bioprocess Eng. 2010;15(1):167–72.10.1007/s12257-009-0154-4Search in Google Scholar
[44] Benzina S, Harquail J, Jean S, Beauregard AP, Colquhoun C, Carroll M, et al. Deoxypodophyllotoxin isolated from Juniperus communis induces apoptosis in breast cancer cells. Anticancer Agent Med Chem. 2015;15(1):79–88.10.2174/1871520614666140608150448Search in Google Scholar PubMed
[45] Lantto TA, Laakso I, Dorman H, Mauriala T, Hiltunen R, Kõks S, et al. Cellular stress and p53-associated apoptosis by Juniperus communis L. Berry extract treatment in the human SH-SY5Y neuroblastoma cells. Int J Mol Sci. 2016;17(7):1113.10.3390/ijms17071113Search in Google Scholar PubMed PubMed Central
[46] Keskes H, Belhadj S, Jlail L, El Feki A, Damak M, Sayadi S, et al. LC-MS-MS and GC-MS analyses of biologically active extracts and fractions from Tunisian Juniperus phoenice leaves. Pharm Biol. 2017;55(1):88–95.10.1080/13880209.2016.1230139Search in Google Scholar PubMed PubMed Central
[47] Hui L-M, Zhao G-D, Zhao J-J. δ-Cadinene inhibits the growth of ovarian cancer cells via caspase-dependent apoptosis and cell cycle arrest. Int J Clin Exp Pathol. 2015;8(6):6046–56.Search in Google Scholar
[48] Jiangseubchatveera N, Liawruangrath B, Liawruangrath S, Korth J, Pyne SG. The chemical constituents and biological activities of the essential oil and the extracts from leaves of Gynura divaricata (L.) DC. Growing in Thailand. J Essent Oil Bear Plants. 2015;18(3):543–55.10.1080/0972060X.2014.935016Search in Google Scholar
[49] Legault J, Pichette A. Potentiating effect of β‐caryophyllene on anticancer activity of α‐humulene, isocaryophyllene and paclitaxel. J Pharm Pharmacol. 2007;59(12):1643–7.10.1211/jpp.59.12.0005Search in Google Scholar PubMed
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