Lupeol Induces Apoptosis and Cell Cycle Arrest of Human Osteosarcoma Cells Through PI3K/AKT/mTOR Pathway

The Role of Dexmedetomidine in Tumor-Progressive Factors in the Perioperative Period and Cancer Recurrence: A Narrative Review

Dexmedetomidine, a specific α2 adrenergic receptor agonist, is highly frequently used in the perioperatively for its favorable pharmacology, such as mitigating postoperative cognitive dysfunction. Increasing attention has been recently focused on the effect of whether dexmedetomidine influences cancer recurrence, which urges the discussion of the role of dexmedetomidine in tumor-progressive factors. The pharmacologic characteristics of dexmedetomidine, the tumor-progressive factors in the perioperative period, and the relationships between dexmedetomidine and tumor-progressive factors were described in this review. Available evidence suggests that dexmedetomidine could reduce the degree of immune function suppression, such as keeping the number of CD3+ cells, NK cells, CD4+/CD8+ ratio, and Th1/Th2 ratio stable and decreasing the level of proinflammatory cytokine (interleukin 6 and tumor necrosis factor-alpha) during cancer operations. However, dexmedetomidine exhibits different roles in cell biological behavior depending on cancer cell types. The conclusions on whether dexmedetomidine would influence cancer recurrence could not be currently drawn for the lack of strong clinical evidence. Therefore, this is still a new area that needs further exploration.

Protective effect of lupeol on arthritis induced by type II collagen via the suppression of P13K/AKT signaling pathway in Sprague dawley rats

To explore the therapeutic value of lupeol on collagen-induced arthritis (CIA) in rats, a rheumatoid arthritis model. Lupeol is well known pentacyclic triterpene found in various plant sources, which possess anti-inflammatory and antioxidant actions. The current study was assessed the anti-arthritic potential of lupeol and its molecular mechanisms as compared with indomethacin (Indo) in collagen-induced arthritis CIA rats. The rats were randomly alienated into five groups: Control, CIA alone, CIA + lupeol (10 mg/kg bw), CIA + Indomethacin (3 mg/kg bw), and lupeol (10 mg/kg bw) alone. The paw volume, biochemical, hematological parameters, inflammatory enzymes, and cytokines were measured. As well protein expression of apoptotic proteins, and histopathological of ankle joint were examined. Inflammatory markers, cytokines, histological changes, paw volume, and inflammation were intensely reduced and enhanced apoptosis by lupeol. Alterations in hematological parameters, rheumatoid factor, C-reactive protein, and ceruloplasmin in arthritis were reverted by lupeol. Protein expressions of Bcl-2, and P13K/Akt signaling were declined, whereas the Bax, caspssae-3, and caspase-9 were elevated. These results highlighted that lupeol suppresses P13K/Akt signaling and has a promising anti-arthritic potential for collagen-induced rheumatic arthritis treatment. Hence lupeol would be suggested as an alternative natural source with potent anti-inflammatory and apoptotic actions for chronic inflammatory disorders.

Calcyclin (S100A6) Attenuates Inflammatory Response and Mediates Apoptosis of Chondrocytes in Osteoarthritis via the PI3K/AKT Pathway

OBJECTIVE

To clarify the regulatory effect of Calcyclin (S100A6) on chondrocytes apoptosis and its relationship with progression of osteoarthritis in an effort to explore potential therapeutic targets for osteoarthritis.

METHOD

Immunofluorescence assay was produced to identify the rat chondrocyte sample and western blots assay was detected the expression changes of S100A6 between control group and osteoarthritis model which induced by interleukin-1β. Adenovirus were transfected into the chondrocytes in vitro, in order to regulate the S100A6 expression. The influence of S100A6 on inflammatory reaction of osteoarthritis was detected by RT-PCR. Also, Caspase-3 activity assay and TUNEL assay were performed to evaluate the apoptosis changes. In addition, RT-PCR and western blots were performed to verify that S100A6 mediated the PI3K/AKT signaling pathway. Through the usage of pathway regulator, we detected S100A6 produced the effect by mediating the PI3K/AKT pathway.

RESULTS

We determined the expression of S100A6 decreased in osteoarthritis model, the relative expression level in osteoarthritis model was about 0.5 fold compared with control group. Through adenovirus transfection we revealed that the inflammatory factors of osteoarthritis (interleukin-6 and matrix metalloproteinase-13) showed a negative correlation with the S100A6 expression. The relative expression level of interleukin-6 and matrix metalloproteinase-13 were 1.534 and 1.259 when S100A6 was up-regulated and the values were up to 2.445 and 2.074, respectively, when S100A6 was down-regulated. Also, the data verified the apoptosis could be reduced when the S100A6 was up-regulated and be activated when the S100A6 was down-regulated, the Caspase-3 activity was 16.512 U/μg and 24.45 U/μg respectively. Similar results were shown in TUNEL assay, the apoptosis index was 4.46% and 31.44%, respectively. Additionally, the results of polymerase chain reaction and western blots both demonstrated that the expression level of PI3K and AKT were increased when S100A6 was up-regulated, conversely the expression level of those two signal modules were reduced if the S100A6 was down-regulated. More importantly, the apoptosis triggered by S100A6 can be offset by the PI3K/AKT pathway inhibitor and activator (LY294002 and IGF-1), the values of Caspase-3 activity and apoptosis index became close to the untreated osteoarthritis group. The experimental results in this study were statistically significant.

CONCLUSION

We investigated that Calcyclin (S100A6) relieved the inflammation and mediated the chondrocyte apoptosis through PI3K/AKT pathway and we confirmed that S100A6 might be an attractive therapeutic target.

Lupeol induces autophagy and apoptosis with reduced cancer stem-like properties in retinoblastoma via phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin inhibition

OBJECTIVES

To evaluate the anticancer effects of lupeol in retinoblastoma cells.

METHODS

WERI-Rb-1 and Y-79 cell lines were used to evaluate the anticancer effect of lupeol. After lupeol treatment, the viability, proliferation, apoptosis, cancer stem-like properties, autophagy and in vivo tumour xenograft formation were detected.

KEY FINDINGS

In this study, lupeol decreased cell viability in both WERI-Rb-1 and Y-79 cell lines. Lupeol could also inhibit proliferation and induce apoptosis of RB cells, with increased Bax level and decreased Ki67, survivin and Bcl-2 levels. Furthermore, lupeol could suppress the spheroid formation and stem-like properties of RB cells. Moreover, LC3 II/LC3 I ratio and the levels of Beclin1 and ATG7 were increased after lupeol treatment, indicating that lupeol could induce autophagy in RB cells. Next, the inhibitory effect of lupeol on the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway was observed. In tumour-bearing mice, lupeol suppressed tumour growth, and this might relate to its role in cell apoptosis, autophagy and stem-like properties.

CONCLUSIONS

Lupeol suppressed proliferation and cancer stem-like properties, and promoted autophagy and apoptosis of RB cells by restraining the PI3K/AKT/mTOR pathway.

Lupeol inhibits osteosarcoma progression by up-regulation of HMGA2 via regulating miR-212-3p

Background

Osteosarcoma (OS) is a common severe illness globally. Lupeol has been reported to participate in the pathophysiologic properties of various cancers, including OS. This study aimed to explore the effects of lupeol on proliferation, invasion, and apoptosis on OS cells and the underlying mechanism.

Methods

The cell viability of OS cells was determined by 3-(4, 5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The expression levels of miR-212-3p and high-mobility group AT-hook 2 (HMGA2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) in OS cells. The cell apoptosis and invasion were detected by flow cytometry and transwell invasion assays, respectively. The functional target of miR-212-3p was predicted by online software and confirmed by luciferase reporter assay. The protein level of HMGA2 was measured by western blot analysis.

Results

Lupeol suppressed cell viability and invasion, and promoted apoptosis by upregulating the expression of miR-212-3p in OS cells. Knockdown of miR-212-3p restored the anti-tumor effect of lupeol. Interestingly, miR-212-3p directly targeted HMGA2 and suppressed its expression. Moreover, HMGA2 reversed the inhibited impact on viability and invasion, and the promoted effect on apoptosis induced by upregulation of miR-212-3p. Also, lupeol administration exerts its anti-tumor effect by overexpression of miR-212-3p to suppress the expression of HMGA2 in OS cells.

Conclusion

Lupeol inhibited OS progression by modulating the miR-212-3p/HMGA2 axis in vitro.

TGF-β is associated with poor prognosis and promotes osteosarcoma progression via PI3K/Akt pathway activation

Transforming growth factor beta (TGF-β) is a multifunctional cytokine with important functions in cell proliferation and differentiation. TGF-β is highly expressed in several types of cancers and promotes tumor invasion and metastasis. However, the role of TGF-β in osteosarcoma progression is poorly understood. In the present study, we found that TGF-β is highly expressed in osteosarcoma cells and tissues, and is associated with high Ennecking stage (P = 0.033), metastasis, and recurrence. TGF-β-knockdown osteosarcoma cell lines were established using siRNA (si-TGF-β). Cells transfected with si-TGF-β exhibited significantly reduced proliferation, migration/invasion, and colony formation abilities, and increased levels of cell apoptosis. In addition, si-TGF-β treatment reduced spheroid size, the ratio of CD133-positive cells, and expression of SOX-2, Nanog, and Oct-3/4 in osteosarcoma cells. Mechanistically, PI3K/mTOR phosphorylation is inhibited by TGF-β knockdown. Pretreatment with 25 µM LY294002, a PI3K-specific inhibitor, further enhanced the si-TGF-β-induced suppression of osteosarcoma progression. Taken together, these results reveal a novel role for TGF-β in osteosarcoma progression and modulation of stemness-related traits and indicate that TGF-β may be of value as a therapeutic target for the treatment of osteosarcoma.

Phytochemical profile and antiproliferative effect of Ficus crocata extracts on triple-negative breast cancer cells

Background

Some species of the Ficus genus show pharmacological activity, including antiproliferative activity, in cell lines of several cancer Types. ficus crocata is distributed in Mexico and used in traditional medicine, as it is believed to possess anti-inflammatory, analgesic, and antioxidant properties. However, as of yet, there are no scientific reports on its biological activity. This study aims to evaluate the phytochemical profile of F. crocata leaf extracts and their effects on breast cancer MDA-MB-231 cells proliferation. Moreover, the study aims to unearth possible mechanisms involved in the decrease of cell proliferation.

Methods

The extracts were obtained by the maceration of leaves with the solvents hexane, dichloromethane, and acetone. The phytochemical profile of the extracts was determined using gas chromatography coupled with mass analysis. Cell proliferation, apoptosis, and cell cycle analysis in MDA-MB-231 cells were determined using a Crystal violet assay, MTT assay, and Annexin-V/PI assay using flow cytometry. The data were analyzed using ANOVA and Dunnett’s test.

Results

The hexane (Hex-EFc), dichloromethane (Dic-EFc), and acetone (Ace-EFc) extracts of F. crocata decreased the proliferation of MDA-MB-231 cells, with Dic-EFc having the strongest effect. Dic-EFc was fractioned and its antiproliferative activity was potentiated, which enhanced its ability to induce apoptosis in MDA-MB-231 cells, as well as increased p53, procaspase-8, and procaspase-3 expression.

Conclusions

This study provides information on the biological activity of F. crocata extracts and suggests their potential use against triple-negative breast cancer.

Chemosensitization of Therapy Resistant Tumors: Targeting Multiple Cell Signaling Pathways by Lupeol, A Pentacyclic Triterpene

Background:

The resistance of cancer cells to different therapies is one of the major stumbling blocks for successful cancer treatment. Various natural and pharmaceuticals drugs are unable to control drug-resistance cancer cell's growth. Also, chemotherapy and radiotherapy have several side effects and cannot apply to the patient in excess. In this context, chemosensitization to the therapy-resistant cells by non-toxic phytochemicals could be an excellent alternative to combat therapy-resistant cancers.

Objective:

To review the currently available literature on chemosensitization of therapy resistance cancers by Lupeol for clinically approved drugs through targeting different cell signaling pathways.

Methods:

We reviewed relevant published articles in PubMed and other search engines from 1999 to 2019 to write this manuscript. The key words used for the search were “Lupeol and Cancer”, “Lupeol and Chemosensitization”, “Lupeol and Cell Signaling Pathways”, “Cancer Stem Cells and Lupeol” etc. The published results on the chemosensitization of Lupeol were compared and discussed.

Results:

Lupeol chemosensitizes drug-resistant cancer cells for clinically approved drugs. Lupeol alone or in combination with approved drugs inhibits inflammation in different cancer cells through modulation of expression of IL-6, TNF-α, and IFN-γ. Lupeol, through altering the expression levels of BCL-2, BAX, Survivin, FAS, Caspases, and PI3K-AKT-mTOR signaling pathway, significantly induce cell deaths among therapy-resistant cells. Lupeol also modulates the molecules involved in cell cycle regulation such as Cyclins, CDKs, P53, P21, and PCNA in different cancer types.

Conclusion:

Lupeol chemosensitizes the therapy-resistant cancer cells for the treatment of various clinically approved drugs via modulating different signaling pathways responsible for chemoresistance cancer. Thus, Lupeol might be used as an adjuvant molecule along with clinically approved drugs to reduce the toxicity and increase the effectiveness.

A natural diarylheptanoid protects cortical neurons against oxygen–glucose deprivation-induced autophagy and apoptosis

Objectives

This study aims to investigate the neuroprotective effects of curcumin analogues, 7-(4-Hydroxy-3-methoxyphenyl)-1-phenyl-4E-hepten-3-one (AO-2) on oxygen–glucose deprivation and re-oxygenation (OGD/R) induced injury in cortical neurons, which is a widely accepted in-vitro model for ischaemic reperfusion.

Methods

In this study, AO-2 was added to cortical neurons for 2 h as pretreatment, and then cortical neurons were subjected to OGD/R in the presence of AO-2 for 4 h. Cell viability was tested by 2′, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay and apoptosis by flow cytometry and Live & Dead cell assay. Western blot analysis detected the change in AKT/mTOR (mammalian target of rapamycin) signalling pathway.

Key findings

Treatment of AO-2 increased cell survival of OGD/R-treated cortical neurons. Transient AKT/mTOR inhibition, induction of the autophagy marker LC3-II (microtubule-associated protein 1A/1B-light chain 3 phosphatidylethanolamine conjugate), and cleavage of the apoptosis marker Caspase-3 were observed at different stages of OGD/R, and AO-2 reversed all three events. Importantly, treatment of the mTOR inhibitor rapamycin blocked the neuroprotective effects of AO-2 on reducing LC3-II and cleaved Caspase-3 expression and cancelled AO-2-mediated neuronal survival.

Conclusions

These results demonstrate that AO-2 increases resistance of cortical neurons to OGD/R by decreasing autophagy and cell apoptosis, which involves an mTOR-dependent mechanism.

Chinese Herbal Medicine for Osteosarcoma in the Mouse: A Systematic Review and Meta-Analysis

OBJECTIVE

To summarize and critically assess the inhibitory effects of Chinese herbal medicine (CHM) on tumor volume and tumor weight for the treatment of osteosarcoma (OS) in mouse models.

METHODS

PubMed, Embase, Web of Science, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, VIP Database, and Chinese BioMedical (CBM) were searched since their inception dates to March 10, 2016. Two reviewers independently selected the controlled studies estimating effects of CHM on mouse OS by administration in vivo. A pair-wise meta-analysis was performed. Twenty-five studies with adequate randomization were included in the systematic review.

RESULTS

CHM may significantly inhibit OS growth in mice, as assessed using the tumor weight [20 studies, n=443; 290 for CHM and 153 for the control: pooled mean difference (MD)=-2.90; 95% confidence interval (Cl): -3.50 to -2.31: P<0.01], tumor volume (16 studies, n=382; 257 for CHM and 125 for the control; pooled MD =-2.57; 95% Cl: -3.33 to -1.80; P<0.01) and tumor growth inhibition rate.

CONCLUSION

CHM could significantly inhibit the growth of OS in mouse models, which might be supportive for the design of preclinical and clinical trials in future.

Clinical significance of Stathmin1 expression and epithelial-mesenchymal transition in curatively resected gastric cancer

In our previous study, it was demonstrated that the Stathmin1 (STMN1) is overexpressed in gastric cancer (GC) and that its high expression level is associated with tumor invasion and metastasis. Epithelial-mesenchymal transition (EMT) has also been shown to be critically involved in GC invasion and metastasis. Certain studies have indicated that STMN1 may serve an important role in the EMT process. However, the association between STMN1 expression and EMT-associated markers, as well as clinicopathological characteristics of patients with GC, remains unclear. The aim of the present study was to investigate the clinicopathological significance and prognostic value of STMN1 and EMT-associated markers in GC. The expression of STMN1 and the EMT-associated proteins E-cadherin (E-Cad) and vimentin (VIM) were analyzed by immunohistochemistry in GC and adjacent non-tumorous tissues. Associations between the expression of these markers and clinicopathological parameters were analyzed. The association between STMN1 expression and EMT-associated markers was investigated in the GC cell lines BGC-803 and SGC-7901. The results revealed that STMN1 was expressed in 63.5% of the 167 GC tissues, which was significantly higher than the percentage observed in the adjacent non-tumorous tissues (P=0.003). The STMN1 expression was demonstrated to be positively associated with the VIM levels (P=0.001) and negatively associated with the E-Cad levels (P=0.022) in GC tissues. The STMN1 expression was associated with Lauren's Classification, invasion depth, lymph node metastasis and pathological Tumor-Node-Metastasis (pTNM) stage (P<0.05). In the univariate analyses, the high E-Cad expression was a positive prognostic indicator for overall survival, whereas the high STMN1 and VIM expression was a negative indicator. COX multiple regression analysis demonstrated that the pTNM stage [hazard ratio (HR) 1.912, 95% confidence interval (CI): 1.282–2.851, P=0.001] and E-Cad expression (HR 0.403, 95% CI: 0.249–0.650, P=0.000) were independent prognostic factors. It was also revealed that the expression level of E-Cad decreased, while the expression level of VIM increased by depleting STMN1 levels in GC cells. The present results suggest that the aberrant expression of STMN1 may promote tumor progression through EMT in GC.

Bone marrow mesenchymal stem cell transplantation exerts neuroprotective effects following cerebral ischemia/reperfusion injury by inhibiting autophagy via the PI3K/Akt pathway

Although cerebral ischemia itself is associated with a high rate of disability, secondary cerebral ischemia/reperfusion (I/R) injury following recanalization is associated with much more severe outcomes. The mechanisms underlying cerebral I/R injury are complex, involving neuronal death caused by apoptosis and autophagy. Autophagy is critical for cell survival and plays an important role in the pathogenesis of cerebral I/R injury. Research has indicated that transplantation of bone marrow mesenchymal stem cells (BMSCs) is effective in repairing and reconstructing brain tissue, and that this effect may be associated with the regulation of autophagy. To explore this hypothesis, we intravenously transplanted BMSCs into a rat model of cerebral I/R injury (middle cerebral artery occlusion [MCAO]). Our results indicated that BMSCs transplantation promoted behavioral recovery, reduced cerebral infarction volume, and decreased the number of apoptotic cells in rats exposed to cerebral I/R injury. Moreover, this effect was associated with reduced expression of the autophagy-associated proteins microtubule-associated protein 1 light chain 3 (LC3) and Beclin-1. Furthermore, BMSCs remarkably increased the expression of p-Akt and p-mTOR following cerebral I/R injury. Expression of LC3 also increased when the PI3K pathway was blocked using LY294002. In summary, our results indicated that the protective effects of BMSCs in cerebral I/R injury may be associated with the inhibition of autophagy via the activation of the PI3K/Akt/mTOR signaling pathway.

Overexpression of HOXC10 promotes glioblastoma cell progression to a poor prognosis via the PI3K/AKT signalling pathway

OBJECTIVE

The HOX gene is expressed in neoplasias occurred in multiple tissues, such as the colon, lung and breast. However, the effects of the HOX gene on glioblastoma (GBM) remain poorly understood. We examined HOXC10 expression in GBM tissues and cells, analysed its effect on GBM prognosis, and finally assessed its possible underlying mechanisms in this study.

METHODS

HOXC10 expression levels and its prognostic effects on GBM tissues were analysed based on The Cancer Genome Atlas (TCGA) and ONCOMINE database. Overall survival (OS) analysis was performed using the Kaplan-Meier method and log rank test. Then, the expression of HOXC10 was detected in four GBM cell lines using quantitative real-time reverse transcription-PCR (qRT-PCR). In addition, small interfering RNA (si-RNA) was utilised in the U87 cell line with the highest HOXC10 expression to facilitate subsequent in vitro cell experiment. Cell proliferation, migration and invasion were assessed using the Cell Counting Kit-8 (CCK-8) and colony formation assay, wound healing, Transwell assay, respectively in GBM U87 cell after HOXC10 knockdown. Key proteins related to the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signalling pathway were measured by western blotting.

RESULTS

HOXC10 expression was significantly increased in GBM tissues and cell lines, leading a poor OS in GBM patients. Knockdown of HOXC10 could inhibit the GBM U87 cells proliferation, migration and invasion, as well as decreased expression levels of key proteins in PI3K/AKT signalling pathway.

CONCLUSION

HOXC10 was overexpressed in GBM tissues and cells, and associated with poor prognosis in GBM patients. Moreover, HOXC10 knockdown inhibited U87 cell proliferation, migration and invasion, which were potentially related to PI3K/AKT signalling pathway activation. Our findings revealed that HOXC10 represent a promising biological target for GBM treatment in the future.

Sorbus commixta water extract induces apoptotic cell death via a ROS-dependent pathway

The stembark of Sorbus commixta Hedl. has been used for treating asthma, bronchitis, gastritis and edema. However, the anticancer and proapoptotic effects of the water extract of the stembark of S. commixta (SCE) remain unknown. In the present study, it was shown that SCE inhibited the cell viability of the hepatocellular carcinoma cell lines Hep3B and HepG2, and of the colon carcinoma cell line HCT116. DNA content analysis indicated that SCE increased the sub-G1 population of HCT116 cells. In addition, degradation of nuclear DNA and levels of proapoptotic cascade components, including caspase-9, caspase-3 and poly ADP-ribose polymerase, were augmented by SCE treatment. Mitochondrial membrane potential and the ratio of B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X protein (Bax) were also reduced. Furthermore, SCE increased the expression of proapoptotic proteins, including p21, p27 and p53. Mouse double minute 2 homology, a negative regulator of p53, was cleaved by SCE treatment. Intracellular reactive oxygen species (ROS) production was also increased by SCE treatment. However, the SCE-induced cytotoxic effects and the increased expression of proapoptotic proteins, including p53 and p21, and reduced Bcl-2/Bax ratio, could be attenuated by N-acetyl cysteine, an ROS inhibitor. Taken together, these results indicate that SCE is a potent proapoptotic herbal medicine, which exerts its effects via the ROS-mediated mitochondrial pathway.

Anticancer activity and concurrent analysis of ursolic acid, β-sitosterol and lupeol in three different Hibiscus species (aerial parts) by validated HPTLC method

The genus Hibiscus contains about 275 species of flowering plants widely grown in the tropics and sub-tropics. The available literature revealed that several Hibiscus species exhibited excellent anticancer activity against several cancer cells like lung, breast, and liver. This motivated the authors to explore the anticancer property of other Hibiscus species (Hibiscus calyphyllus, H. deflersii and H. micranthus) along with development of a validated HPTLC method for the concurrent analysis of three anticancer biomarkers (ursolic acid, β-sitosterol and lupeol) in different Hibiscus species. The anticancer activity of various fractions (petroleum ether, toluene, dichloromethane, ethyl acetate and n-butanol) of all the Hibiscus species (aerial parts) were evaluated in vitro against HepG2 and MCF-7 cell lines using MTT assay. The HPTLC analysis was carried out using chloroform and methanol as mobile phase (97:3; v/v) on 20 × 10 cm glass-backed silica gel 60F254 plates and analyzed different phytoconstituents present in all fractions at λ = 575 nm wavelength. Of the tested fractions of H. calyphyllus, H. deflersii and H. micranthus, HdP (H. deflersii petroleum ether fraction) exhibited the most potent cytotoxic effect on HepG2 and MCF-7 (IC50: 14.4 and 11.1 μg/mL, respectively) cell lines. Using the developed HPTLC method a compact and intense peak of ursolic acid, β-sitosterol and lupeol were obtained at R_f = 0.22, 0.39 and 0.51, respectively. The LOD/LOQ (ng) for ursolic acid, β-sitosterol and lupeol were found as 42.30/128.20, 13.20/40.01 and 31.57/95.68, respectively in the linearity range 100–1200 ng/spot. The obtained result showed maximum presence of ursolic acid, β-sitosterol and lupeol (5.50, 11.85 and 7.47 μg/mg, respectively) in HdP which also supported its strong anticancer effect. Our data suggest that H. deflersii petroleum ether fraction (HdP) can be further subjected to the isolation of active cytotoxic phytoconstituents and establishment of their mechanism of action. The maiden developed HPTLC method for concurrent analysis of anticancer biomarkers may be further employed in the in process quality control of herbal formulation containing the said biomarkers.

mTOR: An attractive therapeutic target for osteosarcoma?

Osteosarcoma (OS) is a common primary malignant bone tumor with high morbidity and mortality in children and young adults. How to improve poor prognosis of OS due to resistance to chemotherapy remains a challenge. Recently, growing findings show activation of mammalian target of rapamycin (mTOR), is associated with OS cell growth, proliferation, metastasis. Targeting mTOR may be a promising therapeutic approach for treating OS. This review summarizes the roles of mTOR pathway in OS and present research status of mTOR inhibitors in the context of OS. In addition, we have attempted to discuss how to design a better treatment project for OS by combining mTOR inhibitor with other drugs.

Honokiol induces autophagy and apoptosis of osteosarcoma through PI3K/Akt/mTOR signaling pathway

Honokiol is the main active constituent of Magnolia officinalis. With effective and long‑term pharmacological functions of being antibacterial, anti‑oxidative, anti‑inflammatory, antitumor, anti‑spasmic, anti‑anxiety and anti‑viral, Honokiol is clinically used in the treatment of acute enteritis and chronic gastritis. The aim of the present study was to observe the possible anti‑effects of honokiol on autophagy and apoptosis of osteosarcoma, and to investigate the role of the PI3K/Akt/mTOR signaling pathway in its anticancer effects. MTT assay was used to evaluate cell proliferation and Annexin V‑fluorescein isothiocyanate/propidium iodide staining flow cytometry was used to analyze the apoptotic rate. The authors identified that honokiol could inhibit cell proliferation and induce the apoptotic rate of osteosarcoma cells. The expression level of Bcl‑2‑like protein 4, caspase‑3 and p53 protein expression were induced and cyclin D1 protein expression was suppressed in osteosarcoma cells by honokiol. Autophagy‑associated LC3II protein expression level was promoted, and PI3K, p‑Akt and p‑mTOR protein expression level was suppressed in osteosarcoma cells by honokiol. The present study demonstrated, to the best of the authors' knowledge, for the first time that honokiol induces autophagy and apoptosis of osteosarcoma cells through the PI3K/Akt/mTOR signaling pathway.

SLC34A2 Regulates the Proliferation, Migration, and Invasion of Human Osteosarcoma Cells Through PTEN/PI3K/AKT Signaling

Osteosarcoma (OS) is a bone malignancy with high incidence. The underlying molecular mechanisms that are associated with the development of OS need further investigation. In this study, we showed that SLC34A2, a member of the solute carrier gene family, was significantly downregulated in OS patients and cell lines. Overexpression of SLC34A2 inhibited the proliferation, migration, and invasion of OS cells. Mechanistically, we found that SLC34A2 interacted with PTEN, and inactivated the PI3K/AKT signaling pathway. Collectively, our results demonstrated that SLC34A2 plays important roles in regulating the cancer cell growth of OS. The downregulation of SLC34A2 in OS patients suggested that it might be a promising target in the diagnosis and therapy of OS.

Lupeol and Its Role in Chronic Diseases

Lupeol belongs to pentacyclic lupane-type triterpenes and exhibits in edible vegetables, fruits and many plants. Many researches indicated that lupeol possesses many beneficial pharmacological activities including antioxidant, anti-inflammatory, anti-hyperglycemic, anti-dyslipidemic and anti-mutagenic effects. From various disease-targeted animal models, these reports indicated that lupeol has anti-diabetic, anti-asthma, anti-arthritic, cardioprotective, hepatoprotective, nephroprotective, neuroprotective and anticancer efficiency under various routes of administration such as topical, oral, subcutaneous, intraperitoneal and intravenous. It is worth mentioning that clinical trials of lupeol were performed to treat canine oral malignant melanoma and human moderate skin acne in Japan and Korea. The detailed mechanism of anti-inflammatory, anti-diabetic, hepatoprotective and anticancer activities was further reviewed from published papers. These evidence indicate that lupeol is a multi-target agent to exert diverse pharmacological potency with many potential targeting proteins such as α-glucosidase, α-amylase, protein tyrosine phosphatase 1B (PTP 1B) and TCA cycle enzymes and targeting pathway such as IL-1 receptor-associated kinase-mediated toll-like receptor 4 (IRAK-TLR4), Bcl-2 family, nuclear factor kappa B (NF-kB), phosphatidylinositol-3-kinase (PI3-K)/Akt and Wnt/β-catenin signaling pathways. This review also provides suggestion that lupeol might be a valuable and potential lead compound to develop as anti-inflammatory, anti-diabetic, hepatoprotective and anticancer drugs.

[ARTICLE WITHDRAWN] Dexmedetomidine Inhibits Osteosarcoma Cell Proliferation and Migration, and Promotes Apoptosis by Regulating miR-520a-3p

This study aimed to investigate the effect of dexmedetomidine (DEX) on osteosarcoma (OS) cell line MG63 and to explore the possible relationship between DEX and miR-520-3p in OS. The results showed that DEX could upregulate miR-520-3p, which directly targeted AKT1. Additionally, miR-520-3p also inhibited MG63 cell proliferation and migration, promoted apoptosis, and suppressed protein expressions of AKT, p-AKT, p-mTOR, and p-ERK1/2. DEX can inhibit OS cell proliferation and migration and promote apoptosis by upregulating the expression level of miR-520a-3p. DEX may serve as a potential therapeutic agent in OS treatment, and miR-520a-3p may be a potential target in the therapy of OS.

Cucurbitacin E inhibits osteosarcoma cells proliferation and invasion through attenuation of PI3K/AKT/mTOR signalling pathway

Cucurbitacin E (CuE), a potent member of triterpenoid family isolated from plants, has been confirmed as an antitumour agent by inhibiting proliferation, migration and metastasis in diverse cancer. However, the effects and mechanisms of CuE on osteosarcoma (OS) have not been well understood. The present study aimed to test whether CuE could inhibit growth and invasion of OS cells and reveal its underlying molecular mechanism. After various concentrations of CuE treatment, the anti-proliferative effect of CuE was assessed using the cell counting Kit-8 assay. Flow cytometry analysis was employed to measure apoptosis of OS cells. Cell cycle distribution was analysed by propidium iodide staining. Transwell assay was performed to evaluate the effect of CuE on invasion potential of OS cells. The protein levels were measured by western blot. In addition, the potency of CuE on OS cells growth inhibition was assessed in vivo Our results showed that CuE inhibited cell growth and invasion, induced a cell cycle arrest and triggered apoptosis and modulated the expression of cell growth, cell cycle and cell apoptosis regulators. Moreover, CuE inhibited the PI3K/Akt/mTOR pathway and epithelial-mesenchymal transition (EMT), which suppressed the invasion and metastasis of OS. In addition, we also found that CuE inhibited OS cell growth in vivo Taken together, our study demonstrated that CuE could inhibit OS tumour growth and invasion through inhibiting the PI3K/Akt/mTOR signalling pathway. Our findings suggest that CuE can be considered to be a promising anti-cancer agent for OS.

Aberrant expression of microRNA-99a and its target gene mTOR associated with malignant progression and poor prognosis in patients with osteosarcoma

Background

The mammalian target of rapamycin (mTOR) has been reported to act as a target gene of microRNA (miR)-99a in various cancer cells and identified as an independent prognostic marker of human osteosarcoma. The aim of this study was to investigate the clinical significance of miR-99a/mTOR axis in human osteosarcoma.

Methods

A total of 130 pairs of osteosarcoma and matched noncancerous bone tissues were used to detect the expression levels of miR-99a and mTOR mRNA by quantitative real-time polymerase chain reaction. Then, associations of miR-99a and/or mTOR expression with clinico-pathological features and prognosis of patients with osteosarcoma were statistically analyzed.

Results

The expression levels of miR-99a (tumor vs normal: 2.11±1.03 vs 4.69±1.21, P<0.001) and mTOR mRNA (tumor vs normal: 4.40±1.13 vs 1.74±0.85, P<0.001) in osteosarcoma tissues were, respectively, lower and higher than those in noncancerous bone tissues. The expression levels of miR-99a in osteosarcoma tissues were negatively correlated with those of mTOR mRNA. Additionally, miR-99a-low and/or mTOR-high expression were all significantly associated with advanced surgical stage, positive metastasis and recurrence, and poor response to chemotherapy (all P<0.05). Moreover, patients with osteosarcoma with miR-99a-low and/or mTOR-high expression had shorter overall and disease-free survivals than those in miR-99a-high and/or mTOR-low expression groups. Multivariate Cox analyses showed that miR-99a and/or mTOR expression were all independent prognostic factors of osteosarcoma.

Conclusion

Our data showed the crucial role of miR-99a/mTOR axis in the malignant progression of human osteosarcoma, implying that conjoined expression of miR-99a and mTOR may offer an attractive novel prognostic marker for this disease.

Lupeol enhances inhibitory effect of 5-fluorouracil on human gastric carcinoma cells

Lupeol, a dietary triterpene present in many fruits and medicinal plants, has been reported to possess many pharmacological properties including cancer-preventive and anti-cancer effects in vitro and in vivo. Here, we investigated the anti-cancer efficacy and adjuvant chemotherapy action of lupeol in gastric cancer (GC) cells (SGC7901 and BGC823) and explored the underlying mechanisms. Cells were treated with lupeol and/or 5-fluorouracil (5-Fu) and subjected to cell viability, colony formation, apoptosis, western blot, semiquantitative RT-PCR, and xenograft tumorigenicity assay. Our results showed that lupeol and 5-Fu inhibited the proliferation of SGC7901 and BGC823 cells, and combination treatment with lupeol and 5-Fu resulted in a combination index < 1, indicating a synergistic effect. Co-treatment with lupeol and 5-Fu induced apoptosis through up-regulating the expressions of Bax and p53 and down-regulating the expressions of survivin and Bcl-2. Furthermore, co-treatment displayed more efficient inhibition of tumor weight and volume on BGC823 xenograft mouse model than single-agent treatment with 5-Fu or lupeol. Taken together, our findings highlight that lupeol sensitizes GC to 5-Fu treatment, and combination treatment with lupeol and 5-Fu would be a promising therapeutic strategy for human GC treatment.