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Diabetic nephropathy (DN) is an increasing threat to human health and is regarded as an important public issue. The pathophysiologic mechanisms of DN are complicated. The initiating molecular events triggering the loss function in mesangial cells (MCs) in DN are not well known. In this cross-disciplinary study, transcriptome analysis of high glucose (HG)-treated mouse MCs (MMCs) using next-generation sequencing and systematic bioinformatics analyses indicated that miR-15b-5p and its downstream target B cell lymphoma 2 (BCL-2) contribute to HG-induced apoptosis in MMCs. HG elevated miR-15b-5p expression, which in turn decreased the translation of BCL-2, leading to MMC apoptosis under HG. Apoptosis of MCs was enhanced in the presence of extracellular vesicles isolated from the urine of type 2 diabetic patients with high levels of miR-15b-5p. Furthermore, increased levels of urinary miR-15b-5p were found in db/db mice and type 2 diabetic patients, and such levels correlated with low baseline kidney function and rapid decline in kidney function during a mean of follow-up period of 2.4 ± 0.1 years. Therefore, miR-15b-5p induced mesangial cells apoptosis by targeting BCL-2 under HG. miR-15b-5p has the potential to predict kidney injury in DN. Blocking the miR-15b-5p epigenetic regulatory network could be a potential therapeutic strategy to prevent mesangial apoptosis in DN.

Patients receiving hemodialysis (HD) have a higher risk of cognitive impairment and dementia than the general population. The accumulation of uremic toxins in the brain causes uremic encephalopathy, however, limited data exists to elucidate the effect of protein-bound uremic toxins on cognitive function. Here we investigate the effect of indole-3 acetic acid (IAA) and hippuric acid (HA), two different protein-bound uremic toxins from amino acid derivatives, on cognitive function by Silico and in a clinical study. Prevalent HD patients were enrolled in two independent hospitals. Serum IAA and HA were measured using mass spectrometry. Cognitive performance was measured using Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Cognitive Abilities Screening Instrument (CASI) by trained psychologists. Using silico data to predict the effect of blood-brain barrier penetration was performed. The silico data demonstrated that IAA and HA had positive blood-brain barrier penetration ability. Amongst the 230 HD patients, serum IAA was associated with poor MMSE score (β= -0.90, 95% CI -1.61 to -0.19) and poor CASI score (β= -3.29, 95% CI -5.69 to -0.88) in stepwise multiple linear regression analysis. In logistic regression model, Serum IAA was also associated with cognitive impairment based on MMSE definition (OR, 1.96, 95% CI 1.10, 3.5) and CASI definition (OR, 2.09, 95% CI 1.21, 3.61). There was no correlation between Serum HA levels and cognitive function status. In conclusion, IAA, not HA, was associated with cognitive impairment in HD patients. Further large scale and prospective studies are needed to confirm our findings.

Hypoxia, the most commonly observed characteristic in cancers, is implicated in the establishment of an immunosuppressive niche. Recent studies have indicated that extracellular vesicle (EV)-mediated cancer-stroma interactions are considered to play a critical role in the regulation of various cellular biological functions, with phenotypic consequences in recipient cells. However, the mechanisms underlying the relationship between EVs and hypoxia during cancer progression remain largely unknown. In this study, we found that EVs derived from hypoxic lung cancers increased M2-type polarization by miR-103a transfer. Decreased PTEN levels caused by hypoxic cancer-cell-derived EV miR-103a increased activation of AKT and STAT3 as well as expression of several immunosuppressive and pro-angiogeneic factors. In contrast, inhibition of miR-103a by an miRNA inhibitor effectively decreased hypoxic cancer-mediated M2-type polarization, improving the cytokine prolife of tumor infiltration macrophages. Macrophages received cancer-cell-derived EV miR-103a feedback to further enhance cancer progression and tumor angiogenesis. Finally, circulating EV miR-103a levels were higher in patients with lung cancer and closely associated with the M2 polarization. In conclusion, our results delineate a novel mechanism by which lung cancer cells induce immunosuppressive and pro-tumoral macrophages through EVs and inspire further research into the clinical application of EV inhibition or PTEN restoration for immunotherapy., Graphical Abstract, Extracellular vesicle (EV) miR-103 can be transferred from hypoxic cancer cells to macrophages, resulting in the enhancement of M2 polarization by the downregulation of miR-103a’s direct target PTEN. EV miR-103a increases the stimulatory effects of macrophages on cancer progression and angiogenesis.

Tamoxifen, a hormonal therapy drug against estrogen receptor-positive breast cancer, can be metabolized by cytochrome P450 enzymes such as CYP3A4 and CYP3A5, and converted to N-desmethyltamoxifen, which is subsequently, metabolized by CYP2D6 and inverted to form 4-hydroxy-N-desmethyltamoxifen (endoxifen). Conventional mass spectrometry (MS) analyses of tamoxifen and its metabolites require isotopic internal standards (ISs). In this study, endoxifen and N-desmethyltamoxifen amine groups were modified by reductive amination with formaldehyde-D2 to produce new metabolite molecules. Both endoxifen and N-desmethyltamoxifen generated their corresponding D2-methyl modified analogs. This method is expected to simplify MS detection and overcome the difficulty in selecting adequate ISs when tamoxifen metabolites are analyzed by absolute quantification. It identified tamoxifen, D2-methyl modified endoxifen, and D2-methyl modified N-desmethyltamoxifen with a linearity ranging from 2 to 5000 ng/mL with correlation coefficient (R(2)) values of 0.9868, 0.9849, and 0.9880, respectively. Furthermore, this reductive amination-based method may enhance the signal intensities of D2-methyl modified N-desmethyltamoxifen and endoxifen, thus facilitating the MS detection.

Background Tolerogenic dendritic cells (tDCs) play important roles in immune tolerance, autoimmune disease, tissue transplantation, and the tumor micro-environment. Factors that induce tDCs have been reported, however the intracellular mechanisms involved are rarely discussed. Methods Circulating CD14+CD16+ of breast cancer patients and induced CD14+CD16+ DCs were identified as tDCs by treating CD14+ monocytes with galectin-1 and cancer cell-derived medium combined with IL-4 and GM-CSF. In addition, the 4T1 breast cancer syngeneic xenograft model was used to investigate the effect of galectin-1 in vivo. Results The CD14+CD16+ tDC population in the breast cancer patients was comparatively higher than that in the healthy donors, and both the MDA-MB-231 conditioned medium and galectin-1 could induce tDC differentiation. In a BALB/c animal model, the 4T1 breast cancer cell line enhanced IL-10 expression in CD11c+ DCs which was down-regulated after knocking down the galectin-1 expression of 4T1 cells. Analysis of galectin-1 interacting proteins showed that myosin IIa was a major target of galectin-1 after internalization through a caveolin-dependent endocytosis. Myosin IIa specific inhibitor could diminish the effects of galectin-1 on monocyte-derived tDCs and also block the 4T1 cell induced CD11c+/Ly6G+/IL-10+ in the BALB/c mice. Conclusions Galectin-1 can induce tDCs after internalizing into CD14+ monocytes through the caveolae-dependent pathway and activating myosin IIa. For the breast cancer patients with a high galectin-1 expression, blebbistatin and genistein show potential in immune modulation and cancer immunotherapy. General significance Myosin IIa activation and galectin-1 endocytosis are important in tumor associated tDC development.

Background 8-Hydroxyquinoline derivatives have highly sensitive fluorescent chemosensors for metal ions, which are associated with anti-oxidant, anti-tumor and anti-HIV-1 properties. Head and neck squamous cell carcinoma (HNSCC) is associated with a high rate of mortality and novel anti-HNSCC drugs must be developed. Therefore, effective chemotherapy agents are required to address this public health issue. Hypothesis/Purpose The aim of this study was to investigate the inhibitory effect of tris(8-hydroxyquinoline)iron (Feq3) on the HNSCC and the underlying mechanism. Study design/Methods A novel 8-hydroxyquinoline derivative, Feq3, was synthesized. The cell viabilities were analyzed using MTT reagent. Apoptosis and the cell cycle distributions were determined by flow cytometer. Reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence, western blot, MitoSOX and CellROX stain assay were used to study the mechanism of Feq3. Feq3 combined with antioxidants NAC (N-acetylcysteine) and BSO (buthionine sulfoximine) measured the cell viability and intracellular ROS. Results Feq3 induced the death of HNSCC cells and caused them to exhibit the morphological features of apoptosis. Feq3 also induced apoptosis of SCC9 cells by cell cycle arrest during the G2/M phase and the induced arrest of SCC25 cells in the G0/G1 and G2/M phases, which was associated with decreased cyclin B1/cdc2 and cyclin D/cdk4 expressions. Feq3 increases reactive oxygen species (ROS) and reduces glutathione (GSH) levels, and responds to increased p53 and p21 expressions. Feq3 induced apoptosis by mitochondria-mediated Bax and cytochrome c up-expression and down-expression Bcl-2. Feq3 also up-regulated tBid, which interacts with the mitochondrial pathway and tumor necrosis factor-α (TNF-α)/TNF-Rs, FasL/Fas, and TNF-related apoptosis inducing ligand receptors (TRAIL-Rs)/TRAIL-dependent caspases apoptotic signaling pathway in HNSCC cells. However, Feq3 activates Fas but not FasL in SCC25 cells. Feq3 arrests the growth of HNSCC cells and is involved in the mitochondria- and death receptor (DR)-mediated caspases apoptotic pathway. Conclusion This study is the first to suggest that apoptosis mediates the anti-HNSCC of Feq3. Feq3 has potential as a cancer therapeutic agent against HNSCC.

This study investigates the anticancer effect of arctigenin (ATG), a natural lignan product of Arctium lappa L., in human breast cancer MDA-MB-231 cells. Results indicate that ATG inhibits MDA-MB-231 cell growth by inducing apoptosis in vitro and in vivo. ATG triggers the mitochondrial caspase-independent pathways, as indicated by changes in Bax/Bcl-2 ratio, resulting in AIF and EndoG nuclear translocation. ATG increased cellular reactive oxygen species (ROS) production by increasing p22(phox)/NADPH oxidase 1 interaction and decreasing glutathione level. ATG clearly increases the activation of p38 MAPK, but not JNK and ERK1/2. Antioxidant EUK-8, a synthetic catalytic superoxide and hydrogen peroxide scavenger, significantly decreases ATG-mediated p38 activation and apoptosis. Blocking p38 with a specific inhibitor suppresses ATG-mediated Bcl-2 downregulation and apoptosis. Moreover, ATG activates ATF-2, a transcription factor activated by p38, and then upregulates histone H3K9 trimethylation in the Bcl-2 gene promoter region, resulting in Bcl-2 downregulation. Taken together, the results demonstrate that ATG induces apoptosis of MDA-MB-231 cells via the ROS/p38 MAPK pathway and epigenetic regulation of Bcl-2 by upregulation of histone H3K9 trimethylation.

Background Bone is a common site of metastasis for lung cancer, and is associated with significant morbidity and a dismal prognosis. MicroRNAs (miRNAs) are increasingly implicated in regulating the progression of malignancies. Methods The efficacy of miR-33a or anti-miR-33a plasmid was assessed by Real-time PCR. Luciferase assays were using One-Glo Luciferase Assay System. Measurement of secreted factors was determined by ELISA kit. Results We have found that miR-33a, which is downregulated in lung cancer cells, directly targets PTHrP (parathyroid hormone-related protein), a potent stimulator of osteoclastic bone resorption, leading to decreased osteolytic bone metastasis. We also found that miR-33a levels are inversely correlated with PTHrP expression between human normal bronchial cell line and lung cancer cell lines. The reintroduction of miR-33a reduces the stimulatory effect of A549 on the production of osteoclastogenesis activator RANKL (receptor activator of nuclear factor kappa-B ligand) and M-CSF (macrophage colony-stimulating factor) on osteoblasts, while the expression of PTHrP is decreased in A549 cells. miR-33a overexpression also reduces the inhibitory activity of A549 on the production of OPG (osteoprotegerin), an osteoclastogenesis inhibitor. In addition, miR-33a-mediated PTHrP downregulation results in decreased IL-8 secretion in A549, which contributes to decreased lung cancer-mediated osteoclast differentiation and bone resorption. Conclusions These findings have led us to conclude that miR-33a may be a potent tumor suppressor, which inhibits direct and indirect osteoclastogenesis through repression of PTHrP. General significance miR-33a may even predict a poor prognosis for lung cancer patients.

During recent decades more than 100,000 new chemicals have been introduced as common consumer products into our environment. Among these chemicals, endocrine-disrupting chemicals (EDCs) are of particular concern owing to their toxicity in animal studies and their impacts on human health. EDCs are ubiquitous in the environment, including the air, water, and soil. The endocrine-disrupting effect of EDCs has been found to imitate the action of steroid hormones and promote several endocrine and reproductive disorders in both animal and human studies. In the present review, we focus on the effects of EDCs on the immune system. EDCs interfere with the synthesis of cytokines, immunoglobulins, and inflammatory mediators, and they also affect the activation and survival of immune cells. The dysfunction of the immune system caused by EDCs may lead to the attenuation of immunity (immunodeficiency) against infection or hyperreactivity of immune responses (allergy and autoimmune disease). In this review, we summarize epidemiologic, animal, and cell studies to demonstrate the potential effects of EDCs on immunity, allergy, and autoimmune diseases. We also address the impact of EDCs on epigenetic regulation.

Although many studies have been performed to elucidate the molecular consequences of ultraviolet irradiation, little is known about the effect of infrared radiation on ocular disease. In addition to photons, heat is generated as a consequence of infrared irradiation, and heat shock is widely considered to be an environmental stressor. Here, we are the first to investigate the biological effect of heat shock on Statens Seruminstitut Rabbit Cornea (SIRC) cells. Our results indicate that heat shock exhibits effective cell proliferation inhibition by inducing apoptosis. Heat shock triggers the mitochondrial apoptotic pathway indicated by a change in Bax/Bcl-2 ratios, resulting in caspase-9 activity. In addition, heat shock triggered the death receptor apoptotic pathway indicated by a change in Fas ligand expression, resulting in caspase-8 activity. Furthermore, we also found that generation of reactive oxygen species (ROS) is a critical mediator in heat shock-induced apoptosis. In addition, the antioxidant vitamin C significantly decreased heat shock-mediated apoptosis. Taken together, these findings suggest a critical role for ROS involving mitochondrial and death receptor pathways in heat shock-mediated apoptosis of cornea cells.

The extracts of Sapindus mukorossi seeds using methanol (MeOH), ethyl acetate (EA) or hexane as solvents were evaluated for their tyrosinase inhibition, free radical scavenging, antimicrobial and anticancer properties. The anti-tyrosinase and antioxidant potentials were determined by in vitro mushroom tyrosinase assay and the radical scavenging method. Both of these results showed minor inhibition abilities at a dosage of 100.0 μg/mL. Antimicrobial activities of S. mukorossi extracts to anti-extensive drug resistant Acinetobacter baumanii (XDRAB) and Pseudomonas aeruginosa (XDRPA) demonstrated good inhibition at 100 μg/mL. The antiproliferative effects of S. mukorossi extracts in human skin, lung, liver, prostate, cervical, bone, bladder, and breast cancer cell lines were also evaluated. Interestingly, S. mukorossi extracts showed strong specific inhibition activities on the proliferation of human melanoma and lung cell lines. The results obtained from biological assays showed that S. mukorossi extracts possessed multiple bioactivities, including anti-tyrosinase, antioxidant, antimicroorganism and anticancer proliferation properties. To our knowledge, this was the first report presenting these bioactivities. The data exhibited the high potential of applying S. mukorossi extracts in medical cosmetology, food supplementation, antibiotics and chemotherapy.

This study first investigates the anticancer effect of kotomolide A (KTA) in human non-small cell lung cancer cells, A549. KTA has exhibited effective cell growth inhibition by inducing cancer cells to undergo G2/M phase arrest and apoptosis. Blockade of cell cycle was associated with increased the activation of ataxia telangiectasia-mutated (ATM). Activation of ATM by KTA phosphorylated p53 at Serine15, resulting in increased stability of p53 by decreasing p53 and murine double minute-2 (MDM2) interaction. In addition, KTA-mediated G2/M phase arrest also was associated with the decrease in the amounts of cyclinB1, cyclinA, Cdc2 and Cdc25C and increase in the phosphorylation of Chk2, Cdc25C and Cdc2. Specific ATM inhibitor, caffeine, significantly decreased KTA-mediated G2/M arrest by inhibiting the phosphorylation of p53 (Serine15) and Chk2. KTA treatment triggered the mitochondrial apoptotic pathway indicated by a change in Bax/Bcl-2 ratios, resulting in mitochondrial membrane potential loss and caspase-9 activation. Taken together, these results suggest a critical role for ATM and p53 in KTA-induced G2/M arrest and apoptosis of human non-small cell lung cancer cells.

This study is the first to investigate the anticancer effect of plumbagin in human melanoma A375.S2 cells. Plumbagin exhibited effective cell growth inhibition by inducing cancer cells to undergo S-G2/M phase arrest and apoptosis. Further investigation revealed that plumbagin’s inhibition of cell growth was also evident in a nude mice model. Blockade of cell cycle was associated with increased levels of p21, and reduced amounts of cyclin B1, cyclin A, Cdc2, and Cdc25C. Plumbagin also enhanced the levels of inactivated phosphorylated Cdc2 and Cdc25C. Plumbagin triggered the mitochondrial apoptotic pathway indicated by a change in Bax/Bcl-2 ratios, resulting in caspase-9 activation. We also found the generation of ROS is a critical mediator in plumbagin-induced cell growth inhibition. Plumbagin increased the activation of apoptosis signal-regulating kinase 1, JNK and extracellular signal-regulated kinase 1/2 (ERK1/2), but not p38. In addition, antioxidants vitamin C and catalase significantly decreased plumbagin-mediated c-Jun N-terminal kinase (JNK) activation and apoptosis. Moreover, blocking ERK and JNK by specific inhibitors suppressed plumbagin-triggered mitochondrial apoptotic pathway. Taken together, these results imply a critical role for ROS and JNK in the plumbagin’s anticancer activity.

In this study, we first report the anti-invasive effect of ethylacetate extract from Antrodia cinnamomea (EAC) fruiting bodies in the human liver cancer cell line PLC/PRF/5. Treatment with EAC decreased the cancer invasion of PLC/PRF/5 cells in a dose-dependent manner. This effect was strongly associated with a concomitant decrease in either the level or activity of VEGF, MMP-2, MMP-9 and MT1-MMP, and an increase in the expression of TIMP-1 and TIMP-2. EAC inhibited constitutively activated and inducible NF-kappaB in both its DNA-binding activity and transcriptional activity. Furthermore, EAC also inhibited the TNF-alpha-activated NF-kappaB-dependent reporter gene expression of MMP-9 and VEGF, and the invasion of cancer cells. EAC also exhibited an inhibitory effect on angiogenesis in a Matrigel Plug Angiogenesis Assay. Further investigation revealed that EAC's inhibition of cancer cell growth and invasion was also evident in a nude mice model. Our results indicate that EAC inhibits the activation of NF-kappaB, and may provide a molecular basis for drug development using EAC as an anti-invasive agent in the prevention and treatment of cancer.

Myricetin (3,3',4',5,5',7-hexahydroxyflavone), a flavonoid compound, is present in vegetables and fruits. By means of alkaline phosphatase (ALP) activity, osteocalcin, and type I collagen enzyme-linked immunosorbent assay (ELISA), we have shown that myricetin exhibits a significant induction of differentiation in MG-63 and hFOB human osteoblasts. Alkaline phosphatase and osteocalcin are phenotypic markers for early-stage differentiated osteoblasts and terminally differentiated osteoblasts, respectively. Our results indicate that myricetin stimulates osteoblast differentiation at various stages, from maturation to terminally differentiated osteoblasts. Induction of differentiation by myricetin is associated with increased bone morphogenetic protein-2 (BMP-2) production. The BMP-2 antagonist noggin blocked myricetin-mediated ALP activity and osteocalcin secretion enhancement, indicating that BMP-2 production is required in myricetin-mediated osteoblast maturation and differentiation. Induction of differentiation by myricetin is associated with increased activation of SMAD1/5/8 and p38 mitogen-activated protein kinases. Cotreatment of p38 inhibitor SB203580 inhibited myricetin-mediated ALP upregulation and osteocalcin production. In conclusion, myricetin increased BMP-2 synthesis, and subsequently activated SMAD1/5/8 and p38 MAPK, and this effect may contribute to its action on the induction of osteoblast maturation and differentiation, followed by an increase of bone mass.

Antrodia cinnamomea is well known in Taiwan as a traditional medicine for treating cancer and inflammation. The purpose of this study was to evaluate the apoptotic effects of ethylacetate extract from A. cinnamomea (EAC) fruiting bodies in Hep 3B, a liver cancer cell line. EAC decreased cell proliferation of Hep 3B cells by inducing apoptotic cell death. EAC treatment increased the level of calcium (Ca2+) in the cytoplasm and triggered the subsequent activation of calpain and caspase-12. EAC also initiated the mitochondrial apoptotic pathway through regulation of Bcl-2 family proteins expression, release of cytochrome c, and activation of caspase-9 in Hep 3B cells. Furthermore, the mitochondrial apoptotic pathway amplified the calpain pathway by Bid and Bax interaction and Ca2+ translocation. We have therefore concluded that the molecular mechanisms during EAC-mediated proliferation inhibition in Hep 3B cells were due to: (1) apoptosis induction, (2) triggering of Ca2+/calpain pathway, (3) disruption of mitochondrial function, and (4) apoptotic signaling being amplified by cross-talk between the calpain/Bid/Bax and Ca2+/mitochondrial apoptotic pathways.

Apigenin, a common dietary flavonoid abundantly present in fruits and vegetables, is believed to possess preventive and therapeutic potential against cancers. In this study, the anti-hepatoma property of apigenin was evaluated on three different human hapatoma cells, namely Hep G2, Hep 3B, and PLC/PRF/5 cells. Results showed that apigenin exhibited a significant growth inhibition against the three selected hepatoma cell lines but not the normal murine liver BNL CL.2 cells. Interestingly, it was shown to possess a similar potency as a commercial anti-hepatoma agent 5-flurouracil (5-FU: positive control) against Hep G2 cells, with IC 50 value of 8.02±1.30 μg/ml. Therefore, we conducted our study further to investigate the cellular mechanism of apigenin effect on Hep G2 cell death. Using DNA ladder and flow cytometric analysis, apigenin was found to induce apoptosis in Hep G2 cells. It also increased the accumulation of p53 and further enhanced the level of p21/WAF1. Together, it was shown that the apoptosis induced by apigenin in Hep G2 cells was possibly mediated through the p53-dependent pathway and the induction of p21 expression, which was probably associated with the cell cycle arrest in G 2 /M phase. The present study concludes that the anti-hepatoma activity of apigenin is as effective as 5-FU and its apoptotic mechanism might be mediated through the p53-dependent pathway and the induction of p21 expression.

The survival of osteoblast cells is one of the determinants of the development of osteoporosis in patients with inflamed synovium, such as in rheumatoid arthritis (RA). By means of alkaline phosphatase (ALP) activity and osteocalcin ELISA assay, I have shown that myricetin exhibits a significant induction of differentiation in the human osteoblast-like cell line MG-63. In addition, I also assessed whether myricetin affects inflammatory cytokines-mediated apoptosis in osteoblast cells. TNF-alpha or IL-1beta enhances apoptotic DNA fragmentation in anti-Fas IgM-treated MG-63 cells by increasing Fas receptor expression. However, TNF-alpha or IL-1beta treatment alone does not induce apoptosis. Treatment of MG-63 cells with myricetin not only inhibited anti-Fas IgM-induced apoptosis, but also blocked the synergetic effect of anti-Fas IgM with TNF-alpha or IL-1beta on cell death. The apoptotic inhibition of myricetin is associated with inhibition of TNF-alpha and IL-1beta-mediated Fas expression and enhancement of FLIP expression, resulting in a decrease of caspase-8 and caspase-3 activation. These results indicate a potential use of myricetin in preventing osteoporosis by inhibiting inflammatory cytokines-mediated apoptosis in osteoblast cells.

Isoliquiritigenin (ISL) is a natural pigment with the simple chalcone structure 4,2′,4′-trihydroxychalcone. In this study, we report ISL induced inhibition in the proliferation of human hepatoma cells (Hep G2) for the first time. The cell proliferation inhibition achieved by ISL treatment resulted in a G2/M-phase arrest and programmed cell death. ISL treatment was found to result in the upregulation of p53, p21/WAF1, Fas/APO-1 receptor, Fas ligand, Bax and NOXA, but not in Bad. To elevate the role of p53 in these functions, we generated Hep G2 cells that express the dominant negative p53, which blocks the transcriptional activity of p53. The enhancement of p21/WAF1, Fas/APO-1, Bax and NOXA were decreased in Hep G2 cells that lack functional p53. Furthermore, Hep G2 cells were significantly more resistant to ISL when the activity of p53 was blocked. These results demonstrated that ISL-inducible p53 plays a key apoptotic role, and may do so by regulating the expression of specific target molecules that promotes efficient apoptotic cell death following G2/M-cell cycle arrest.

The fruiting body of Antrodia camphorata is well known in Taiwan as a traditional medicine for treating cancer and inflammation. The purpose of this study was to evaluate the apoptotic effects of ethylacetate extract from A. camphorata (EAC) fruiting bodies in two human liver cancer cell lines, Hep G2 and PLC/PRF/5. Treatment with EAC decreased the cell growth of Hep G2 and PLC/PRF/5 cells in a dose dependent manner. In Fas/APO-1 positive-Hep G2 cells, EAC increased the expression level of Fas/APO-1 and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), in a p53-indenpendent manner. In addition, EAC also initiated mitochondrial apoptotic pathway through regulation of Bcl-2 family proteins expression, release of cytochrome c, and activation of caspase-9 both in Hep G2 and PLC/PRF/5 cells. Furthermore, EAC also inhibited the cell survival signaling by enhancing the amount of IkappaBalpha in cytoplasm and reducing the level and activity of NF-kappaB in the nucleus, and subsequently attenuated the expression of Bcl-X(L) in Hep G2 and PLC/PRF/5 cells. EAC therefore decreased the cell growth and induced apoptosis both in Hep G2 and PLC/PRF/5 cells.

Luteolin is a common constituent of many kinds of fruits and vegetables. It possesses the anti-neoplastic activities against several human cancers, but its activity against hepatocellular carcinoma (HCC) is seldom mentioned. To evaluate the activity against HCC and to provide information about the mechanism, we tested luteolin against five human hepatoma cell lines, namely HepG2, SK-Hep-1, PLC/PRF/5, Hep3B, and HA22T/VGH, with XTT assay and flow cytometry. The results showed that luteolin inhibited PLC/PRF/5, Hep3B and HA22T/VGH at a concentration of 1 microg/ml, but it needed 5 microg/ml to inhibit HepG2 and 10 microg/ml for SK-Hep1 (P

In this study, we report the proapoptotic effect of saikosaponin d in two liver cancer cell lines, Hep G2 and Hep 3B cells. Treatment with saikosaponin d decreased the cell proliferation of Hep G2 and Hep 3B cells in a dose dependent manner. In Hep G2, saikosaponin d blocked the progression of cell cycle at G1 phase by inducing p53 expression and further up-regulating p21/WAF1 expression. In addition, an enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), as well as Bax protein, was responsible for the apoptotic effect induced by saikosaponin d. Furthermore, saikosaponin d also inhibited the cell survival signaling by enhancing the amount of IkappaBalpha in cytoplasm and reducing the level and activity of NF-kappaB in the nucleus, and subsequently attenuated the expression of Bcl-XL in Hep G2 and Hep 3B cells. Saikosaponin d therefore decreased the cell proliferation and inducted apoptosis both in p53-positive Hep G2 and p53-negative Hep 3B cells.

Ursolic acid (UA) is a pentacyclic triterpene compound isolated from many types of medicinal plants and is present in human diet. It has been reported to possess a wide range of pharmacological properties, and is one of the most promising chemopreventive agents for cancer. Here, we report that UA inhibits the cell proliferation of human lung cancer cell line A549 and provide a molecular understanding of this effect. The results showed that UA blocked cell cycle progression in the G1 phase that was associated with a marked decrease in the protein expression of cyclin D1, D2, and E and their activating partner cdk2, 4, and 6 with concomitant induction of p21/WAF1. This accumulation of p21/WAF1 might be through a p53-dependent manner. Further, UA treatment also resulted in the triggering of apoptosis as determined by DNA fragmentation assay. This effect was found to correlate with the up-regulation of Fas/APO-1, Fas ligand, and Bax, and down-regulation of NF-kappaB, Bcl-2, and Bcl-XL. Taken together, our study indicated that UA might be a potential chemopreventive agent for lung cancer.

In this study, we examined acacetin (5,7-dihydroxy-4'-methoxyflavone), a flavonoid compound, for its effect on proliferation in human non-small cell lung cancer A549 cells. The results first reported that acacetin not only inhibited A549 cell proliferation but also induced apoptosis and blocked cell cycle progression in the G1 phase. ELISA assay demonstrated that acacetin significantly increased the expression of p53 and p21/WAF1 protein, which caused cell cycle arrest. An enhancement in Fas and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), might be responsible for the apoptotic effect induced by acacetin. Taken together, p53 and Fas/FasL apoptotic system may participate in the antiproliferative activity of acacetin in A549 cells.

Resveratrol, a phytoalexin found in many plants, has been reported to possess a wide range of pharmacological properties and is one of the promising chemopreventive agents for cancer. Here, we examined the antiproliferation effect of resveratrol in two human liver cancer cell lines, Hep G2 and Hep 3B. Our results showed that resveratrol inhibited cell growth in p53-positive Hep G2 cells only. This anticancer effect was a result of cellular apoptotic death induced by resveratrol via the p53-dependent pathway. Here we demonstrated that the resveratrol-treated cells were arrested in G1 phase and were associated with the increase of p21 expression. In addition, we also illustrated that the resveratrol-treated cells had enhanced Bax expression but they were not involved in Fas/APO-1 apoptotic signal pathway. In contrast, the p53-negative Hep 3B cells treated with resveratrol did not show the antiproliferation effect neither did they show significant changes in p21 nor Fas/APO-1 levels. In summary, our study demonstrated that the resveratrol effectively inhibited cell growth and induced programmed cell death in Hepatoma cells on a molecular basis. Furthermore, these results implied that resveratrol might also be a new potent chemopreventive drug candidate for liver cancer as it played an important role to trigger p53-mediated molecules involved in the mechanism of p53-dependent apoptotic signal pathway.

Indoleamine 2,3-dioxygenase (IDO) is a rate limiting enzyme in tryptophan-degrading pathways and IDO activity results in immune suppression. Targeting IDO is a strategy of cancer immunotherapies. Our previous studies demonstrate that delivery of short hairpin against IDO (IDO shRNA) suppresses tumor growth and increases neutrophils infiltration into tumor. Neutrophils reveal antitumorigenic “N1” or protumorigenic “N2” phenotype in tumor microenvironment. However, the function of IDO shRNA-induced neutrophils is not clear. The LLC1 lung cancer model was used to investigate the role of these neutrophils. Intramuscular injection of IDO shRNA or IDO inhibitor treatment delayed tumor growth and both treatments increased neutrophil infiltration in tumor. Enriched tumor-infiltrating neutrophils expressed both high level of tumor necrosis factor-α and tumor necrosis factor-β (N1 and N2 associated molecules, respectively). In addition, IDO shRNA treatment induced interferon-γ and tryptophan transfer RNA expression in splenocytes. Systematic depletion of neutrophils abolished the IDO shRNA-induced therapeutic effect but did not affect the effect of IDO inhibitor. The levels of interferon-γ and tumor necrosis factor-α were suppressed in IDO shRNA treatment splenocytes after neutrophils depletion. In conclusion, these tumor-infiltrating neutrophils show antitumorigenic phenotype in spleen after IDO shRNA treatment in a murine lung cancer model.