Development of an Efficient Dual-Action GST-Inhibiting Anticancer Platinum(IV) Prodrug

The cytotoxicity of cisplatin (cDDP) is enhanced when co-administered with ethacrynic acid (EA), a glutathione S-transferase (GST) inhibitor. A Pt^IV -EA conjugate containing a cDDP core and two axial ethacrynate ligands (compound 1) was shown to be an excellent inhibitor of GST, but did not readily release a Pt^II species to exert a synergistic cytotoxic effect. In this study, a redesigned Pt^IV construct composed of a cDDP core with one axial ethacrynate ligand and one axial hydroxido ligand (compound 2) was prepared and shown to overcome the limitations of compound 1. The EA ligand in 2 is readily released in vitro together with a cytotoxic Pt^II species derived from cisplatin, working together to inhibit cell proliferation in cDDP-resistant human ovarian cancer cells. The in vitro activity translates well in vivo with 2, showing effective (∼80 %) inhibition of tumor growth in a human ovarian carcinoma A2780 tumor model, while showing considerably lower toxicity than cisplatin, thus validating the new design strategy.

Inhibitory effects of Danhong Injection and its major constituents on human cytochrome P450 enzymes in vitro

Danhong Injection (DHI) as a Chinese patent medicine is mainly used to treat ischemic encephalopathy and coronary heart disease in combination with other chemotherapy. However, the information on DHI's potential drug interactions is limited. The goal of this work was to examine the potential P450-mediated metabolism drug interaction arising from DHI and its active components. The results showed that DHI inhibited CYP2C19, CYP2D6, CYP3A4, CYP2E1 and CYP2C9 with IC₅₀ values of 1.26, 1.42, 1.63, 1.10 and 1.67% (v/v), respectively. Danshensu and rosmarinic acid inhibited CYP2E1 and CYP2C9 with IC₅₀ values of 36.63 and 75.76 μm, and 34.42 and 76.89 μm, respectively. Salvianolic acid A and B inhibited CYP2D6, CYP2E1 and CYP2C9 with IC₅₀ values of 33.79, 21.64 and 31.94 μm, and 45.47, 13.52 and 24.15 μm, respectively. The study provides some useful information for safe and effective use of DHI in clinical practice.

Biglycan promotes the chemotherapy resistance of colon cancer by activating NF-κB signal transduction

Biglycan (BGN) is overexpressed in cancer stem cells of colon cancer and induces the activation of NF-κB pathway which contributes to the chemotherapy resistance of diverse cancer types. Therefore, we hypothesized that the overexpression of BGN also promoted the development of multiple drug resistance (MDR) in colon cancer via NF-κB pathway. The expression of BGN was bilaterally modulated in colon cancer cell lines HT-29 and SW-480 and the effect of treatments on the cell proliferation and resistance to 5-FU was assessed. Moreover, the role of NF-κB signaling in the BGN-mediated formation of MDR was further investigated by subjecting BGN-overexpressed SW-480 cells to the co-treatment of chemo-agents and NF-κB inhibitor, PDTC. The inhibition of BGN expression decreased the proliferation potential of HT-29 cells while the induction of BGN expression increased the potential of SW-480 cells. BGN knockdown increased HT-29 cells' sensitivity to 5-FU, represented by the lower colony number and higher apoptotic rate. To the contrary, BGN overexpression promoted the resistance of SW-480 cells to 5-FU. The effect of BGN modulation on colon cancer cells was associated with the changes in apoptosis and NF-κB pathways: BGN inhibition increased the expressions of pro-apoptosis indicators and suppressed NF-κB pathway activity while BGN overexpression had the opposite effect. It was also found that the BGN-mediated formation of MDR was impaired when NF-κB pathway was blocked. Findings outlined in the current study showed that BGN contributed to the formation of chemotherapy resistance in colon cancer cells by activating NF-κB signaling.

Icariin, but Not Genistein, Exerts Osteogenic and Anti-apoptotic Effects in Osteoblastic Cells by Selective Activation of Non-genomic ERα Signaling

Genistein and icariin are flavonoid compounds that exhibit estrogen-like properties in inducing bone formation and reducing bone loss associated with estrogen deficiency in both preclinical and clinical studies. However, the mechanisms that are involved in mediating their estrogenic actions in bone cells are far from clear. The present study aimed to study the signaling pathways that mediate the estrogenic actions of genistein and icariin in osteoblastic cells. The effects of genistein and icariin on the activation of estrogen receptor (ER) and the downstream mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway in murine osteoblastic MC3T3-E1 cells and rat osteoblastic UMR-106 cells were studied. As expected, genistein displayed higher binding affinity toward ERβ than ERα and significantly induced estrogen response element (ERE)-dependent transcription in UMR-106 cells in a dose-dependent manner. In contrast, icariin failed to bind to ERα or ERβ and did not induce ERE-dependent transcription in UMR-106 cells at 10^-10 to 10^-7 M. The effects of genistein (10 nM) and icariin (0.1 μM) on cell proliferation and differentiation in osteoblastic UMR-106 cells were abolished in the presence of ER antagonist ICI 182,780 (1 μM), MAPK inhibitor U0126 (10 μM), and PI3K inhibitor LY294002 (10 μM). Genistein at 10 nM rapidly induced ERK1/2 phosphorylation at 5–10 min in UMR-106 cells and the phosphorylation of ERα at both Ser118 and Ser167 in both MC3T3-E1 and transfected UMR-106 cells whereas icariin at 0.1 μM rapidly activated both ERK1/2 and Akt phosphorylation in UMR-106 cells and subsequent ERα phosphorylation at both Ser118 and Ser167 in MC3T3-E1 and transfected UMR-106 cells. Confocal imaging studies confirmed that the phosphorylation of ERα at Ser 118 and Ser 167 by genistein and icariin in MC3T3-E1 cells was mediated via MAPK- and PI3K-dependent pathway, respectively. Furthermore, our studies showed that icariin exerted stronger anti-apoptotic effects than genistein and 17β-estradiol (E2) and inhibited the cleavage of downstream caspase-3 in MC3T3-E1 cells induced by a potent PI3K inhibitor, PI828 (at 2 μM). These results indicated that the mechanisms that mediate the estrogenic actions of icariin in osteoblastic cells are different from those of genistein.

Autophagy and doxorubicin resistance in cancer

Doxorubicin (DOX), also known as adriamycin, is a DNA topoisomerase II inhibitor and belongs to the family of anthracycline anticancer drugs. DOX is used for the treatment of a wide variety of cancer types. However, resistance among cancer cells has emerged as a major barrier to effective treatment using DOX. Currently, the role of autophagy in cancer resistance to DOX and the mechanisms involved have become one of the areas of intense investigation. More and more preclinical data are being obtained on reversing DOX resistance through modulation of autophagy as one of the promising therapeutic strategies. This review summarizes the recent advances in autophagy-targeting therapies that overcome DOX resistance from in-vitro studies to animal models for exploration of novel delivery systems. In-depth understanding of the mechanisms of autophagy regulation in relation to DOX resistance and development of molecularly targeted autophagy-modulating agents will provide a promising therapeutic strategy for overcoming DOX resistance in cancer treatment.

Metformin increases the cytotoxicity of oxaliplatin in human DLD-1 colorectal cancer cells through down-regulating HMGB1 expression

Colorectal cancer (CRC) is the fourth most common cause of cancer death worldwide. Chemotherapy has been the major strategy for treating patients with advanced CRC. Oxaliplatin (OXA) is used as both an adjuvant and neoadjuvant anticancer agent available to treat advanced CRC. High-mobility group box 1 protein (HMGB1) is a critical regulator of cell death and survival. HMGB1 overexpression has been shown to be resistant to cytotoxic agents. In addition, Metformin, a widely used drug for diabetes, has emerged as a potential anticancer agent. In this study, we examined whether HMGB1 plays a role in the OXA- and/or metformin-induced cytotoxic effect on CRC cells. The results showed that treatment with OXA increased HMGB1 expression in the ERK1/2- and Akt-dependent manners in DLD-1 cells. HMGB1 gene knockdown enhanced the cytotoxicity and cell growth inhibition of OXA. Moreover, OXA-increased HMGB1 expression was by inducing NF-κB-DNA-binding activity to in DLD-1 cells. Compared to a single agent, OXA combined with metformin administration resulted in cytotoxicity and cell growth inhibition synergistically, accompanied with reduced HMGB1 level. These findings may have implications for the rational design of future drug regimens incorporating OXA and metformin for the treatment of CRC.

Cryptotanshinone inhibits proliferation yet induces apoptosis by suppressing STAT3 signals in renal cell carcinoma

It has been established that signal transducer and activator of transcription 3 serves as an oncoprotein in various human cancers; targeting it is therefore a reasonable approach for emerging cancer therapies. Cryptotanshinone, a natural compound extracted from the root of Salvia miltiorrhiza Bunge, has been identified as a potential STAT3 inhibitor. However, its functional role in renal cell carcinomas remains largely unknown. Therefore, we investigated the mode of action for cryptotanshinone. We found that cryptotanshinone substantially suppressed cancer cell growth while it promoted cell apoptosis by inhibiting the phosphorylation of STAT3 at Tyr705 and its blocking nuclear translocation. Coordinately, P-AKT, CyclinD1, C-MYC, MEKK2, and HGF were down-regulated and cell cycle progression was arrested at the G0/G1 phase, thereby attenuating cell proliferation. Moreover, the level of Cleaved-Caspase-3 was elevated while Bcl-2 and Survivin were down-regulated, accounting for the increased apoptosis. Furthermore, in vivo results revealed that cryptotanshinone effectively inhibits tumorigenesis in an A498-xenografted mouse model. Taken together, our data gives a more comprehensive understanding of how cryptotanshinone functions in renal cell carcinomas and demonstrates its potential as a powerful therapeutic approach to treat renal cell carcinomas.

PMN inhibits colorectal cancer cells through inducing mitotic arrest and p53-dependent apoptosis via the inhibition of tubulin polymerization

Colorectal cancer (CRC) is the third most prevalent malignancy worldwide. New understandings about this disease are urgently required to guide clinical therapies. In this study, we focused on the effects of the small molecule PMN on CRC cells. PMN dose-dependently inhibited CRC cell proliferation through inducing mitotic arrest and apoptosis. PMN induced mitotic arrest via the disruption of spindle apparatus by inhibiting microtubule polymerization. PMN-induced mitotic arrest resulted in apoptosis and p53 upregulation. Furthermore, p53 upregulation sensitized PMN-induced mitotic cells to apoptosis. This study deepens the understanding of the effects of p53 on the response of CRC cells to PMN, providing the basis for the potential development of PMN as a lead compound of microtubule-destabilizers for p53-positive CRC treatment.

A novel 5T4-targeting antibody-drug conjugate H6-DM4 exhibits potent therapeutic efficacy in gastrointestinal tumor xenograft models

5T4, also named as trophoblast glycoprotein, is often upregulated in some cancer cells. Here, we demonstrated that 5T4 was highly expressed in gastric, colorectal, and pancreatic cancer, associated with significantly poor prognosis of gastrointestinal (GI) cancer patients. To search for new targeting drugs for GI cancer, we developed a novel anti-5T4 monoclonal antibody with high affinity and robust internalization ability and conjugated it to the potent microtubule inhibitor DM4 to produce conjugate H6-DM4. This antibody-drug conjugate (ADC) displayed significant cytotoxicity in a panel of GI cancer cell lines with IC50 values in the nanomolar range. H6-DM4 eradicated established GI tumor xenograft models at 2.5 mg/kg or 10 mg/kg without observable toxicity. Further, 5T4 was highly expressed in cancer-initiating cells (CICs) compared with non-CICs in colorectal cancer. In vitro and in vivo, treatment with H6-DM4 exhibited a powerful efficacy on colorectal CICs. Additionally, colorectal cancer cells resistant to platinum were effectively eliminated by H6-DM4. Taken together, our results showed 5T4-positive GI cancer cells, colorectal cancer-initiating cells, and platinum-resistant colorectal cancer cells were potently eliminated by H6-DM4, indicating H6-DM4 may be a potential candidate drug for GI cancer treatment.

Natural products as modulator of autophagy with potential clinical prospects

Natural compounds derived from living organisms are well defined for their remarkable biological and pharmacological properties likely to be translated into clinical use. Therefore, delving into the mechanisms by which natural compounds protect against diverse diseases may be of great therapeutic benefits for medical practice. Autophagy, an intricate lysosome-dependent digestion process, with implications in a wide variety of pathophysiological settings, has attracted extensive attention over the past few decades. Hitherto, accumulating evidence has revealed that a large number of natural products are involved in autophagy modulation, either inducing or inhibiting autophagy, through multiple signaling pathways and transcriptional regulators. In this review, we summarize natural compounds regulating autophagy in multifarious diseases including cancer, neurodegenerative diseases, cardiovascular diseases, metabolic diseases, and immune diseases, hoping to inspire further investigation of the underlying mechanisms of natural compounds and to facilitate their clinical use for multiple human diseases.

Suppression of YAP by DDP disrupts colon tumor progression

Colon cancer is a commonly diagnosed cancer that often has a poor prognosis. Combined with the development of drug resistance to cancer treatment agents the treatment efficacy of colon cancer can be limited. Activation of the oncogene YAP has been shown to be related to colon cancer progression and is associated with poor prognosis, drug resistance and metastasis, even under treatment. Cisplatin (DDP) is a commonly used drug that can control carcinoma progression, although its mechanisms are poorly understood. In the present study, we examined whether DDP specifically suppressed YAP in order to inhibit colon carcinoma progression. Our data revealed that Mst/Yap signaling was unusually activated in colon cancers, promoting cell proliferation and invasion. DDP treatment decreased the expression of YAP at both the transcriptional and post-translational levels, leading to cell cycle arrest, apoptosis and senescence in cancer cells, in addition to decreasing epithelial-to-mesenchymal transition, cell motility and in vitro cell invasion and migration. Ultimately, DDP increased the expression of E-cadherin and decreased the expression of vimentin. The present study also revealed that post-translational regulation of YAP phosphorylation controlled the subcellular distribution between the nucleus and the cytoplasm. In conclusion, the findings of the present study revealed that DDP was a suitable therapeutic candidate for colon cancer that specifically targets the Mst/Yap signaling pathway.

Cullin-1 and -2 Protein Expression in Colorectal Cancer: Correlation with Clinicopathological Variables

BACKGROUND/AIM

The cullin (CUL) family of proteins is involved in the ubiquitin/mediated degradation of proteins, regulating cell proliferation, cell-cycle control, migration, invasion and metastasis in the process of tumor progression. The aim of the present study was to examine if there is any correlation between the immunohistochemical (IHC) expression of Cullin-1 and -2 proteins in colorectal cancer tissue specimens with several clinicopathological variables.

MATERIALS AND METHODS

Between January 2012 and December 2014, 96 consecutive adenocarcinoma patients were submitted to oncological colectomy, as the first therapeutic option, with a curative intent. CUL-1 and -2 protein expression was examined with IHC on paraffin-embedded tissue sections. CUL-1 and -2 protein positivity, was correlated with patients' age, gender, stage, histological grade, proliferative capacity (Ki-67 labeling index) and mutant p53 protein expression. The positivity for CUL-1, CUL-2, mutant p53 protein and Ki-67 index, was determined by the percentage of their IHC expression in the total number of cancer cells.

RESULTS

Choosing as a cut-off point for CUL-1 positivity the 10%, a statistically significant relationship of the expression of the mutant p53 protein (p=0.04) and the co-expression of CUL-2 (p=0.003) were noticed. By setting the cut-off limit for CUL-2 expression to 10%, no statistically significant differences were observed between its expression and the examined clinicopathological variables. However, by increasing the cut-off limit for CUL-2 expression to 30%, a statistically significant correlation of its expression to the mutated p53 protein was noticed (p=0.047). Co-expression of CUL-1 and -2 in more than 10%, significantly correlated to the coexistence of adenomatous polyps along the large bowel (p=0.0329). Multivariate analysis of CUL-1 and -2 co-expression in more than 10% disclosed their expression as an independent factor for adenomatous polyps development in the large bowel (p=0.035, RR=2.1).

CONCLUSION

CUL-1 overexpression may happen early in the process of carcinogenesis mainly affecting the vulnerable p53(+) large bowel cells, arresting them in the G1 phase of cell-cycle, while it may also induce the expression of CUL-2. Co-expression of CUL-1 and CUL-2, in the arrested (in G1 phase) large bowel cells, promotes carcinogenesis up to adenomatous polyp formation. Since no relationship between cullins expression and development of cancer on adenoma was found, the results of the present study may be useful explaining the initiation but not the progression of carcinogenesis in colorectal cancer. Further molecular and clinical studies are needed in order to delineate the clinical importance of these proteins in the management of colorectal cancer patients.

Discovery of indoleamine 2,3-dioxygenase inhibitors using machine learning based virtual screening

Indoleamine 2,3-dioxygenase (IDO), an immune checkpoint, is a promising target for cancer immunotherapy. However, current IDO inhibitors are not approved for clinical use yet; therefore, new IDO inhibitors are still demanded. To identify new IDO inhibitors, we have built naive Bayesian (NB) and recursive partitioning (RP) models from a library of known IDO inhibitors derived from recent publications. Thirteen molecular fingerprints were used as descriptors for the models to predict IDO inhibitors. An in-house compound library was virtually screened using the best machine learning model, which resulted in 50 hits for further enzyme-based IDO inhibitory assays. Consequently, we identified three new IDO inhibitors with IC₅₀ values of 1.30, 4.10, and 4.68 μM. These active compounds also showed IDO inhibitory activities in cell-based assays. The compounds belong to the tanshinone family, a typical scaffold family derived from Danshen (a Chinese herb), the dried root of Salvia miltiorrhiza, which has been widely used in China, Japan, the United States, and other European countries for the treatment of cardiovascular and cerebrovascular diseases. Thus, we discovered a new use for Danshen using machine learning methods. Surface plasmon resonance (SPR) experiments proved that the inhibitors interacted with the IDO target. Molecular dynamic simulations demonstrated the binding modes of the IDO inhibitors.

Drug resistance related to aberrant glycosylation in colorectal cancer

Colorectal cancer (CRC) is the fourth leading cause of cancer-related deaths in the world. Drug resistance of tumour cells remains the main challenge toward curative treatments efficiency. Several epidemiologic studies link emergence and recurrence of this cancer to metabolic disorders. Glycosylation that modifies more than 80% of human proteins is one of the most widepread nutrient-sensitive post-translational modifications. Aberrant glycosylation participates in the development and progression of cancer. Thus, some of these glycan changes like carbohydrate antigen CA 19-9 (sialyl Lewis a, sLea) or those found on carcinoembryonic antigen (CEA) are already used as clinical biomarkers to detect and monitor CRC. The current review highlights emerging evidences accumulated mainly during the last decade that establish the role played by altered glycosylations in CRC drug resistance mechanisms that induce resistance to apoptosis and activation of signaling pathways, alter drug absorption and metabolism, and led to stemness acquisition. Knowledge in this field of investigation could aid to the development of better therapeutic approaches with new predictive biomarkers and targets tied in with adapted diet.

Relation of the IGF/IGF1R system to autophagy in colitis and colorectal cancer

Metabolic syndrome (MetS), as a chronic inflammatory disorder has a potential role in the development of inflammatory and cancerous complications of the colonic tissue. The interaction of DNA damage and inflammation is affected by the insulin-like growth factor 1 receptor (IGF1R) signaling pathway. The IGF1R pathway has been reported to regulate autophagy, as well, but sometimes through a bidirectional context. Targeting the IGF1R-autophagy crosstalk could represent a promising strategy for the development of new antiinflammatory and anticancer therapies, and may help for subjects suffering from MetS who are at increased risk of colorectal cancer. However, therapeutic responses to targeted therapies are often shortlived, since a signaling crosstalk of IGF1R with other receptor tyrosine kinases or autophagy exists, leading to acquired cellular resistance to therapy. From a pharmacological point of view, it is attractive to speculate that synergistic benefits could be achieved by inhibition of one of the key effectors of the IGF1R pathway, in parallel with the pharmacological stimulation of the autophagy machinery, but cautiousness is also required, because pharmacologic IGF1R modulation can initiate additional, sometimes unfavorable biologic effects.

Upregulated solute carrier family 37 member 1 in colorectal cancer is associated with poor patient outcome and metastasis

Solute carrier (SLC) drug transporters exchange various molecules without energy from adenosine triphosphate hydrolysis, indicating an association with anticancer drug resistance. However, the expression and role of SLC transporters in malignant tumors has not yet been fully elucidated. Therefore, in the current study, the expression of SLC37A family genes was evaluated in patients with colorectal cancer (CRC), and it was revealed that SLC family 37 member 1 (SLC37A1) expression was significantly increased in tumorous tissues compared with that in non-tumorous tissues. The cases with upregulated expression of SLC37A1 by immunohistochemical staining were significantly associated with positive venous invasion and liver metastasis. Furthermore, upregulated SLC37A1 expression was associated with poor overall survival time in the present cohort. These results indicated that SLC37A1 is involved in the hematogenous metastasis of CRC. To investigate whether SLC37A1 is associated with hematogenous metastasis and glycolipid metabolism, SLC37A1 was knocked down in colon cancer cells, and the expression of sialyl Lewis A and sialyl Lewis X was observed to be decreased. In summary, upregulation of SLC37A1 was observed in patients with CRC, and was associated with poor patient outcomes and survival. To the best of our knowledge, the present study is the first to propose a key role of SLC37A1 in CRC, and additional studies are warranted to reveal the functional role of SLC37A1 in CRC development.

GOLPH3 expression promotes the resistance of HT29 cells to 5‑fluorouracil by activating multiple signaling pathways

The novel proto‑oncogene Golgi phosphoprotein (GOLPH)3 is overexpressed in a variety of tumor tissues and is associated with poor prognosis. The authors previously demonstrated that GOLPH3 gene is overexpressed in colorectal cancer tissues and promotes the proliferation of colonic cancer cells by activating the phosphatidylinositol‑3‑kinase/protein kinase B/the mammalian target of rapamycin and Wnt/β‑catenin signaling pathways. However, to the best of the authors' knowledge, if and how the GOLPH3 gene is involved in inducing resistance to colonic cancer chemotherapy has not been reported. In the present study, the association between the overexpression of the GOLPH3 gene and resistance of HT29 colonic cancer cells to 5‑fluorouracil (5‑FU) was investigated. Following confirmation of the effective silencing of the GOLPH3 gene, proliferation and apoptosis of colonic cancer cells were detected by MTT assay, colony formation assay and flow cytometry, and then the mechanism of GOLPH3‑induced resistance to 5‑FU chemotherapy in colonic cancer cells was investigated by western blotting. The results demonstrated that the expression of phosphorylated (p)‑glycoprotein and GOLPH3 was increased in HT29 cells following treatment with 5‑FU, which resulted in the development of drug resistance. Silencing GOLPH3 increased the sensitivity of HT29 cells to 5‑FU, reduced their tumorigenicity and partly reversed their resistance to 5‑FU. The expression of p‑extracellular signal‑regulated kinase (pERK)1/2 and β‑catenin was decreased, which indicated that its mechanism was associated with the activation of the mitogen‑activated protein kinase/ERK and Wnt/β‑catenin signaling pathways. Therefore, GOLPH3 may be a potential, novel target for reversing chemotherapy resistance in colon cancer.

Sulforaphane induces p53‑deficient SW480 cell apoptosis via the ROS‑MAPK signaling pathway

Sulforaphane (SFN) has been revealed to inhibit the growth and induce apoptosis of cancer cells. However, the detailed anticancer effects of SFN on p53‑deficient colon cancer cells has yet to be clearly elucidated. The present study employed p53‑deficient SW480 cells to establish an SFN‑induced in vitro model of apoptosis. The critical events leading to apoptosis were then evaluated in SFN‑treated p53‑deficient SW480 cells, by performing an MTT assay, flow cytometry, western blotting and ELISA. The results demonstrated that SFN at concentrations of 5, 10, 15 and 20 µM induced mitochondria‑associated cell apoptosis, which was further confirmed by disruption of the mitochondrial membrane potential, an increase in the Bax/Bcl‑2 ratio, as well as activation of caspase‑3, ‑7 and ‑9. In addition, SFN‑induced apoptosis was associated with an increase in the generation of reactive oxygen species (ROS), and the activation of extracellular signal‑regulated kinases (Erk) and p38 mitogen‑activated protein kinases. However, SFN did not induce expression of the p53 family member, p73. SFN‑induced apoptosis was subsequently confirmed to be ROS‑dependent and associated with Erk/p38, as the specific inhibitors for ROS, phosphorylated (p)‑Erk and p‑p38, completely or partially attenuated the SFN‑induced reduction in SW480 cell viability. In addition, the results demonstrated that even at the lowest concentrations (5 µM), SFN increased the sensitivity of p53‑proficient HCT‑116 cells to cisplatin. In conclusion, the results suggest that SFN may induce apoptosis in p53‑deficient SW480 cells via p53/p73‑independent and ROS‑Erk/p38‑dependent signaling pathways.

Cytotoxicity and mode of action of a naturally occurring naphthoquinone, 2-acetyl-7-methoxynaphtho[2,3-b]furan-4,9-quinone towards multi-factorial drug-resistant cancer cells

INTRODUCTION

Malignacies are still a major public concern worldwide and despite the intensive search of new chemotherapeutic agents, treatment still remains a challenging issue. The present study was designed to evaluate the cytotoxicity of 2-acetyl-7-methoxynaphtho[2,3-b]furan-4,9-quinone (AMNQ) isolated from the bark of Milletia versicolor towards a panel of drug-sensitive and multidrug-resistant (MDR) cancer cell lines.

METHODS

The resazurin reduction assay was used to evaluate the cytotoxicity of AMNQ against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species were all analyzed by flow cytometry.

RESULTS

Following resazurin assay, the naphthoquinone AMNQ displayed IC₅₀ values ranging from 0.79 µM (against HepG2 hepatocarcinoma cells) to 3.26 µM (against MDA-MB231/BCRP breast cancer cells) on 9 tested cancer cell lines, whilst doxorubicin showed IC₅₀ values ranging from 0.40 µM (against CCRF-CEM leukemia cells) to 91.37 µM (against CEM/ADR5000 leukemia cells). IC₅₀ values below 1 µM were recorded with AMNQ towards CCRF-CEM cells (0.57 µM), U87MG.ΔEGFR gliobastoma multiforme cells (0.96 µM cells) and HepG2 cells (0.76 µM). Compared to its corresponding sensitive cell lines U87MG, sensitivity was observed in epidermal growth factor receptor-transfected U87MG.ΔEGFR cells to AMNQ. MMP was found to be the main mode of action of induction of apoptosis by AMNQ.

CONCLUSIONS

The results of this work demonstrate the cytotoxicity of AMNQ towards various types of cancer cell lines, including MDR phenotypes. AMNQ is a potential antiproliferative natural compound that deserves more investigations to develop novel cytotoxic drugs against sensitive and MDR cancers.

Danshen improves survival of patients with colon cancer and dihydroisotanshinone I inhibit the proliferation of colon cancer cells via apoptosis and skp2 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Danshen (Salvia miltiorrhiza Bunge) is widely used in traditional Chinese medicine. However, it's definite clinical effect and mechanism on colon carcinoma is unclear.

AIM OF THE STUDY

To test the hypothesis that the protective effect of danshen on colon cancer and discover the bioactive compounds through in vitro study.

MATERIALS AND METHODS

We conducted a nationwide cohort study by using population-based data from the Taiwan National Health Insurance Research Database (NHIRD). The study cohort comprised patients diagnosed with malignant neoplasm of colon (ICD-9-CM codes:153) in catastrophic illness database between January 1, 2000, and December 31, 2010. We used the Kaplan-Meier method to estimate colon [corrected] cancer cumulative incidences. Next, human colon cancer cells (HCT 116 cells and HT29 cells) were used to investigate the effect of dihydroisotanshinone I (DT) on the proliferation and apoptosis of human colon cancer cells and the underlying mechanism through XTT assay and flow cytometry. The in vivo effect of DT treatment was investigated through a xenograft nude mouse model.

RESULTS

In our study, the in vivo protective effect of danshen in the different stage of colon cancer patients was validated through data from the National Health Insurance Research Database in Taiwan. In vitro, we found that dihydroisotanshinone I (DT), a bioactive compound present in danshen, can inhibit the proliferation of colon carcinoma cells, HCT 116 cells and HT-29 cells. Moreover, DT induced apoptosis of colorectal cancer cells. DT also repressed the protein expression of Skp2 (S-Phase Kinase Associated Protein 2) and the mRNA levels of its related gene, Snail1 (Zinc finger protein SNAI1) and RhoA (Ras homolog gene family, member A). In addition, DT also blocked the colon cancer cells recruitment ability of macrophage by decreasing CCL2 secretion in macrophages. DT treatment also significantly inhibited the final tumor volume in a xenograft nude mouse model.

CONCLUSION

Danshen has protective effects in colon cancer patients, which could be attributed to DT through blocking the proliferation of colon cancer cells through apoptosis.

Glycyrrhizic acid: A promising carrier material for anticancer therapy

Drug delivery systems have become an integral part of anticancer drugs today. Design of novel drug carriers may lead to significant enhancement in antineoplastic therapy. Glycyrrhizic acid (GL), which is the most important active ingredient extracted from the licorice root shows great potential as a carrier material in this field. Recent studies have indicated that the combination of GL and first-line drugs had better therapeutic effects on cancers. GL showed a series of anti-cancer-related pharmacological activities, such as broad-spectrum anti-cancer ability, resistance to the tissue toxicity caused by chemotherapy and radiation, drug absorption enhancing effects and anti-multidrug resistance (MDR) mechanisms, as a carrier material in drug delivery systems. This review introduced the current research progress on pharmacological mechanisms of GL and development of GL-based drug carriers in anti-cancer field to provide basis for the application prospects of GL. The design of novel GL-based drug delivery systems will bring new opportunities and challenges to anti-cancer therapy.

Microscale Mass Spectrometry Analysis of Extracellular Metabolites in Live Multicellular Tumor Spheroids

Extracellular compounds in tumors play critical roles in intercellular communication, tumor proliferation, and cancer cell metastasis. However, the lack of appropriate techniques leads to limited studies of extracellular metabolite. Here, we introduced a microscale collection device, the Micro-funnel, fabricated from biocompatible fused silica capillary. With a small probe size (∼25 μm), the Micro-funnel can be implanted into live multicellular tumor spheroids to accumulate the extracellular metabolites produced by cancer cells. Metabolites collected in the Micro-funnel device were then extracted by a microscale sampling and ionization device, the Single-probe, for real-time mass spectrometry (MS) analysis. We successfully detected the abundance change of anticancer drug irinotecan and its metabolites inside spheroids treated under a series of conditions. Moreover, we found that irinotecan treatment dramatically altered the composition of extracellular compounds. Specifically, we observed the increased abundances of a large number of lipids, which are potentially related to the drug resistance of cancer cells. This study provides a novel way to detect the extracellular compounds inside live spheroids, and the successful development of our technique can benefit the research in multiple areas, including the microenvironment inside live tissues, cell-cell communication, biomarker discovery, and drug development.

Interplay between apoptosis and autophagy in colorectal cancer

Autophagy and apoptosis are two pivotal mechanisms in mediating cell survival and death. Cross-talk of autophagy and apoptosis has been documented in the tumorigenesis and progression of cancer, while the interplay between the two pathways in colorectal cancer (CRC) has not yet been comprehensively summarized. In this study, we outlined the basis of apoptosis and autophagy machinery firstly, and then reviewed the recent evidence in cellular settings or animal studies regarding the interplay between them in CRC. In addition, several key factors that modulate the cross-talk between autophagy and apoptosis as well as its significance in clinical practice were discussed. Understanding of the interplay between the cell death mechanisms may benefit the translation of CRC treatment from basic research to clinical use.

Autophagy and multidrug resistance in cancer

Multidrug resistance (MDR) occurs frequently after long-term chemotherapy, resulting in refractory cancer and tumor recurrence. Therefore, combatting MDR is an important issue. Autophagy, a self-degradative system, universally arises during the treatment of sensitive and MDR cancer. Autophagy can be a double-edged sword for MDR tumors: it participates in the development of MDR and protects cancer cells from chemotherapeutics but can also kill MDR cancer cells in which apoptosis pathways are inactive. Autophagy induced by anticancer drugs could also activate apoptosis signaling pathways in MDR cells, facilitating MDR reversal. Therefore, research on the regulation of autophagy to combat MDR is expanding and is becoming increasingly important. We summarize advanced studies of autophagy in MDR tumors, including the variable role of autophagy in MDR cancer cells.

Comprehensive Identification of Guan-Xin-Shu-Tong Capsule via a Mass Defect and Fragment Filtering Approach by High Resolution Mass Spectrometry: In Vitro and In Vivo Study

The Guan-Xin-Shu-Tong capsule (GXSTC) is a well-known traditional Chinese medicine that is used for the treatment of coronary heart disease. Despite its common use in China, basic pharmacological research on its active components is limited. A comprehensive analytical method using quadrupole-time-of-flight mass spectrometry (Q-TOF/MS), specifically with the Triple TOF 5600 platform, was developed to characterize the compounds in the GXSTC powder itself (in vitro) as well as the active components in healthy and heart disease model rats after its oral administration (in vivo). The 5600 platform was operated in both positive and negative ion modes, before the raw data were processed using the extracted ion chromatography (EIC), mass defect filtering (MDF) and fragment filtering (FF) techniques. With the aid of reference compounds for retention time and fragment ion comparisons, 18 compounds were unambiguously identified in vitro. An additional 56 other compounds were tentatively characterized using the accurate quasi-molecular ion mass and Tandem mass spectrometry (MS/MS) fragmentation pattern strategies. Among them, 30 compounds were characterized based on the MDF and FF approaches. Normal rats in addition to hyperlipidemic (HL) and acute blood stasis (ABS) model rats were given a single oral dose of GXSTC solution for subsequent blood analysis at 1 and 2 h after administration. A total of 24 prototypecomponents and 20 metabolites derived from GXSTC were differentially detected across the three animal groups, including the absence of four phase II phenolic acid metabolites in the ABS group and the presence of three diterpenoid-related metabolites exclusive to the HL group. The use of reference compounds as well as the mass defect and fragment-filtering strategies were critical to identify GXSTC compounds in vitro and in vivo. This can be used for further quality control and pharmacological studies aimed at characterizing the active and potential beneficial compounds of this ancient medicine.

Microbial infection, inflammation and epithelial ovarian cancer

Ovarian cancer is the most common, and life-threatening, type of female gynecological cancer. The etiology of ovarian cancer remains unclear, and there are currently no effective screening or treatment methods for the disease. Microbial infection serves a marked function in inducing carcinogenesis. A number of studies have identified pelvic inflammatory disease as a risk factor for epithelial ovarian cancer. Thus, it is hypothesized that microbial infection may contribute to ovarian cancer. In the present review, the microorganisms that have been identified to be associated with ovarian cancer and the underlying molecular mechanisms involved are discussed. Infection-induced chronic inflammation is considered an important process for carcinogenesis, cancer progression and metastasis. Therefore, the pathological process and associated inflammatory factors are reviewed in the present paper.

Epithelial-mesenchymal transition and cancer stem cell-like phenotype induced by Twist1 contribute to acquired resistance to irinotecan in colon cancer

Inherent and acquired chemoresistance reduce the effectiveness of irinotecan in the treatment of metastatic colorectal cancer (CRC). However, the molecular mechanisms underlying this resistance process are still unclear. Twist1 is one of the master transcription factors of epithelial-mesenchymal transition (EMT). Our previous study indicated that Twist1 is overexpressed in colon cancer tissues, and demonstrated that Twist1 plays a crucial role in the chemoresistance of CRC. In the present study, we further investigated how Twist1 contribute to acquired resistance to irinotecan in colon cancer. The irinotecan-resistant cells were established by gradual adaptation of increasing irinotecan concentrations in LoVo cells, named LoVo/CPT-11R cells. Results showed that cell viabilities to different anticancer drugs were markedly increased in LoVo/CPT-11R cells compared to LoVo cells. Moreover, LoVo/CPT-11R cells displayed EMT, CSC-like cellular morphology and relative biomarkers were also significantly increased. In addition, overexpressed Twist1 LoVo cells were established by lentivirus transfection assay, named LoVo/Twist1 cells. Results showed that the LoVo/Twist1 cells perform a distinctly decreased sensitivity to irinotecan, downregulated expression of E-cadherin, upregulated expression of cluster of differentiation 44 (CD44), and a significant enhancement of invasion and migration potential by regulation of MMP2 compared with control cells. In contrast, the inhibition of Twist1 transfected with siRNA could enhance the irinotecan sensitivity in LoVo/CPT-11R cells and downregulate the expression of vimentin and CD44. Our data provide evidence that EMT and CSC-like phenotype induced by Twist1 contribute to acquire resistance to irinotecan and enhanced migration and invasion in colon cancer.

Aldose reductase inhibitor increases doxorubicin-sensitivity of colon cancer cells and decreases cardiotoxicity

Anthracycline drugs such as doxorubicin (DOX) and daunorubicin remain some of the most active wide-spectrum and cost-effective drugs in cancer therapy. However, colorectal cancer (CRC) cells are inherently resistant to anthracyclines which at higher doses cause cardiotoxicity. Our recent studies indicate that aldose reductase (AR) inhibitors such as fidarestat inhibit CRC growth in vitro and in vivo. Here, we show that treatment of CRC cells with fidarestat increases the efficacy of DOX-induced death in HT-29 and SW480 cells and in nude mice xenografts. AR inhibition also results in higher intracellular accumulation of DOX and decreases the expression of drug transporter proteins MDR1, MRP1, and ABCG2. Further, fidarestat also inhibits DOX-induced increase in troponin-I and various inflammatory markers in the serum and heart and restores cardiac function in mice. These results suggest that fidarestat could be used as adjuvant therapy to enhance DOX sensitivity of CRC cells and to reduce DOX-associated cardiotoxicity.

Dual-functional drug liposomes in treatment of resistant cancers

Efficacy of regular chemotherapy is significantly hampered by multidrug resistance (MDR) and severe systemic toxicity. The reduced toxicity has been evidenced after administration of drug liposomes, consisting of the first generation of regular drug liposomes, the second generation of long-circulation drug liposomes, and the third generation of targeting drug liposomes. However, MDR of cancers remains as an unsolved issue. The objective of this article is to review the dual-functional drug liposomes, which demonstrate the potential in overcoming MDR. Herein, dual-functional drug liposomes are referring to the drug-containing phospholipid bilayer vesicles that possess a dual-function of providing the basic efficacy of drug and the extended effect of the drug carrier. They exhibit unique roles in treatment of resistant cancer via circumventing drug efflux caused by adenosine triphosphate binding cassette (ABC) transporters, eliminating cancer stem cells, destroying mitochondria, initiating apoptosis, regulating autophagy, destroying supply channels, utilizing microenvironment, and silencing genes of the resistant cancer. As the prospect of an estimation, dual-functional drug liposomes would exhibit more strength in their extended function, hence deserving further investigation for clinical validation.

Codelivery of dihydroartemisinin and doxorubicin in mannosylated liposomes for drug-resistant colon cancer therapy

Multidrug resistance (MDR) is a major hurdle in cancer chemotherapy and makes the treatment benefits unsustainable. Combination therapy is a commonly used method for overcoming MDR. In this study we investigated the anti-MDR effect of dihydroartemisinin (DHA), a derivative of artemisinin, in combination with doxorubicin (Dox) in drug-resistant human colon tumor HCT8/ADR cells. We developed a tumor-targeting codelivery system, in which the two drugs were co-encapsulated into the mannosylated liposomes (Man-liposomes). The Man-liposomes had a mean diameter of 158.8 nm and zeta potential of -15.8 mV. In the HCT8/ADR cells that overexpress the mannose receptors, the Man-liposomes altered the intracellular distribution of Dox, resulting in a high accumulation of Dox in the nuclei and thus displaying the highest cytotoxicity (IC₅₀=0.073 μg/mL) among all the groups. In a subcutaneous HCT8/ADR tumor xenograft model, administration of the Man-liposomes resulted in a tumor inhibition rate of 88.59%, compared to that of 47.46% or 70.54%, respectively, for the treatment with free Dox or free Dox+DHA. The mechanisms underlying the anti-MDR effect of the Man-liposomes involved preferential nuclear accumulation of the therapeutic agents, enhanced cancer cell apoptosis, downregulation of Bcl-xl, and the induction of autophagy.

Mechanisms of drug resistance in colon cancer and its therapeutic strategies

Drug resistance develops in nearly all patients with colon cancer, leading to a decrease in the therapeutic efficacies of anticancer agents. This review provides an up-to-date summary on over-expression of ATP-binding cassette (ABC) transporters and evasion of apoptosis, two representatives of transport-based and non-transport-based mechanisms of drug resistance, as well as their therapeutic strategies. Different ABC transporters were found to be up-regulated in colon cancer, which can facilitate the efflux of anticancer drugs out of cancer cells and decrease their therapeutic effects. Inhibition of ABC transporters by suppressing their protein expressions or co-administration of modulators has been proven as an effective approach to sensitize drug-resistant cancer cells to anticancer drugs in vitro. On the other hand, evasion of apoptosis observed in drug-resistant cancers also results in drug resistance to anticancer agents, especially to apoptosis inducers. Restoration of apoptotic signals by BH3 mimetics or epidermal growth factor receptor inhibitors and inhibition of cancer cell growth by alternative cell death pathways, such as autophagy, are effective means to treat such resistant cancer types. Given that the drug resistance mechanisms are different among colon cancer patients and may change even in a single patient at different stages, personalized and specific combination therapy is proposed to be more effective and safer for the reversal of drug resistance in clinics.

Herb-Drug Interactions of Commonly Used Chinese Medicinal Herbs

With more and more popular use of traditional herbal medicines, in particular Chinese herbal medicines, herb-drug interactions have become a more and more important safety issue in the clinical applications of the conventional drugs. Researches in this area are increasing very rapidly. Herb-drug interactions are complicated due to the fact that multiple chemical components are involved, and these compounds may possess diverse pharmacological activities. Interactions can be in both pharmacokinetics and pharmacodynamics. Abundant studies focused on pharmacokinetic interactions of herbs and drugs. Herbs may affect the behavior of the concomitantly used drugs by changing their absorption, distribution, metabolism, and excretion. Studies on pharmacodynamics interactions of herbs and drugs are still very limited. Herb-drug interactions are potentially causing changes in drug levels and drug activities and leading to either therapeutic failure or toxicities. Sometime it can be fatal. The exposures to drugs, lacking of knowledge in the potential adverse herb-drug interactions, will put big risk to patients' safety in medical services. On the contrary, some interactions may be therapeutically beneficial. It may be used to help develop new therapeutic strategies in the future. This chapter is trying to review the development in the area of herb-drug interactions based on the recently published research findings. Information on the potential interactions among the commonly used Chinese medicinal herbs and conventional drugs is summarized in this chapter.

The anti-hepatic fibrosis effects of dihydrotanshinone I are mediated by disrupting the yes-associated protein and transcriptional enhancer factor D2 complex and stimulating autophagy

BACKGROUND AND PURPOSE

Dihydrotanshinone I (DHI), a lipophilic component of traditional Chinese medicine Salvia miltiorrhiza Bunge, has various therapeutic effects. We investigated the anti-fibrotic effect of DHI and its underlying mechanisms in vitro and in vivo.

EXPERIMENTAL APPROACH

Rats subjected to bile duct ligation (BDL) were treated with DHI (25 mg·kg^-1 ·day^-1 , i.p.) for 14 days. Serum biochemical and liver tissue morphological analyses were performed. The human hepatic stellate cell line LX-2 served as a liver fibrosis model in vitro. Liver fibrogenic genes, yes-associated protein (YAP) downstream genes and autophagy markers were examined using western blot and real-time PCR analyses. Similar analyses were done in rat primary hepatic stellate cells (pHSCs). Autophagy flux was assessed by immunofluorescence.

KEY RESULTS

In BDL rats, DHI administration attenuated liver necrosis, bile duct proliferation and collagen accumulation and reduced the expression of genes associated with fibrogenesis, including Tgfb1, Mmp-2, Acta2 and Col1a1. DHI (1, 5, 10 μmol·L^-1 ) time- and dose-dependently suppressed the protein level of COL1A1, TGFβ1 and α-SMA in LX-2 cells and rat pHSCs. Furthermore, DHI blocked the nuclear translocation of YAP, which inhibited the YAP/TEAD2 interaction and its downstream fibrogenic genes, connective tissue growth factor, SOX4 and survivin. This stimulated autophagic flux and accelerated the degradation of liver collagen.

CONCLUSIONS AND IMPLICATIONS

DHI exerts anti-fibrotic effects in BDL rats, LX-2 cells and rat pHSCs by inhibiting the YAP and TEAD2 complex and stimulating autophagy. These findings indicate that DHI may be a potential therapeutic for the treatment of liver fibrosis.

Diterpenes and Their Derivatives as Potential Anticancer Agents

As therapeutic tools, diterpenes and their derivatives have gained much attention of the medicinal scientists nowadays. It is due to their pledging and important biological activities. This review congregates the anticancer diterpenes. For this, a search was made with selected keywords in PubMed, Science Direct, Web of Science, Scopus, The American Chemical Society and miscellaneous databases from January 2012 to January 2017 for the published articles. A total 28, 789 published articles were seen. Among them, 240 were included in this study. More than 250 important anticancer diterpenes and their derivatives were seen in the databases, acting in the different pathways. Some of them are already under clinical trials, while others are in the nonclinical and/or pre-clinical trials. In conclusion, diterpenes may be one of the lead molecules in the treatment of cancer. Copyright © 2017 John Wiley & Sons, Ltd.

Autophagy in 5-Fluorouracil Therapy in Gastrointestinal Cancer: Trends and Challenges

Objective:

5-Fluorouracil (5-FU)-based combination therapies are standard treatments for gastrointestinal cancer, where the modulation of autophagy is becoming increasingly important in offering effective treatment for patients in clinical practice. This review focuses on the role of autophagy in 5-FU-induced tumor suppression and cancer therapy in the digestive system.

Data Sources:

All articles published in English from 1996 to date those assess the synergistic effect of autophagy and 5-FU in gastrointestinal cancer therapy were identified through a systematic online search by use of PubMed. The search terms were “autophagy” and “5-FU” and (“colorectal cancer” or “hepatocellular carcinoma” or “pancreatic adenocarcinoma” or “esophageal cancer” or “gallbladder carcinoma” or “gastric cancer”).

Study Selection:

Critical reviews on relevant aspects and original articles reporting in vitro and/or in vivo results regarding the efficiency of autophagy and 5-FU in gastrointestinal cancer therapy were reviewed, analyzed, and summarized. The exclusion criteria for the articles were as follows: (1) new materials (e.g., nanomaterial)-induced autophagy; (2) clinical and experimental studies on diagnostic and/or prognostic biomarkers in digestive system cancers; and (3) immunogenic cell death for anticancer chemotherapy.

Results:

Most cell and animal experiments showed inhibition of autophagy by either pharmacological approaches or via genetic silencing of autophagy regulatory gene, resulting in a promotion of 5-FU-induced cancer cells death. Meanwhile, autophagy also plays a pro-death role and may mediate cell death in certain cancer cells where apoptosis is defective or difficult to induce. The dual role of autophagy complicates the use of autophagy inhibitor or inducer in cancer chemotherapy and generates inconsistency to an extent in clinic trials.

Conclusion:

Autophagy might be a therapeutic target that sensitizes the 5-FU treatment in gastrointestinal cancer.

Natural Compounds As Modulators of Non-apoptotic Cell Death in Cancer Cells

Cell death is an innate capability of cells to be removed from microenvironment, if and when they are damaged by multiple stresses. Cell death is often regulated by multiple molecular pathways and mechanism, including apoptosis, autophagy, and necroptosis. The molecular network underlying these processes is often intertwined and one pathway can dynamically shift to another one acquiring certain protein components, in particular upon treatment with various drugs. The strategy to treat human cancer ultimately relies on the ability of anticancer therapeutics to induce tumor-specific cell death, while leaving normal adjacent cells undamaged. However, tumor cells often develop the resistance to the drug-induced cell death, thus representing a great challenge for the anticancer approaches. Numerous compounds originated from the natural sources and biopharmaceutical industries are applied today in clinics showing advantageous results. However, some exhibit serious toxic side effects. Thus, novel effective therapeutic approaches in treating cancers are continued to be developed. Natural compounds with anticancer activity have gained a great interest among researchers and clinicians alike since they have shown more favorable safety and efficacy then the synthetic marketed drugs. Numerous studies in vitro and in vivo have found that several natural compounds display promising anticancer potentials. This review underlines certain information regarding the role of natural compounds from plants, microorganisms and sea life forms, which are able to induce non-apoptotic cell death in tumor cells, namely autophagy and necroptosis.

Inflammation by Breast Implants and Adenocarcinoma: Not Always a Bad Company

BACKGROUND

Inflammation and tumor are now an inseparable binomial. Inflammation may also derive by the use of breast implants followed by the formation of a periprosthetic capsule. It is known that tumor cells, in an inflamed microenvironment, can profit by the paracrine effect exerted also by mesenchymal stem cells (MSCs). Here we evaluated the role of inflammation on the immunobiology of MSCs before and after cocultures with cells derived from breast adenocarcinoma.

METHODS

MSCs derived from both inflamed (I-MSCs) and control (C-MSCs) tissues were isolated and cocultured with MCF7 cells derived from breast adenocarcinoma. Before and after cocultures, the proliferation rate of MCF7 cells and the expression/secretion of cytokines related to inflammation were tested.

RESULTS

Before cocultures, higher levels of cytokine related to chronic inflammation were detected in I-MSCs than in C-MSCs. After cocultures with MCF7, C- and I-MSCs show a variation in cytokine production. In detail, IL-2, IL-4, IL-5, IL-10, IL-13, TGF-β and G-CSF were decreased, whereas IL-6, IL-12, IFN-γ, and IL-17 were oversecreted. Proliferation of MCF7 was significantly increased after cocultures with I-MSCs.

CONCLUSIONS

Inflammation at the site of origin of MSCs affects their immunobiology. Even if tumor cells increased their proliferation rate after cocultures with I-MSCs, the analysis of the cytokines, known to play a role in the interference of tumor cells with the host immune system, absolves completely the breast implants from the insult to enforce the risk of adenocarcinoma.

Chinese Herbal Medicine and Fluorouracil-Based Chemotherapy for Colorectal Cancer: A Quality-Adjusted Meta-Analysis of Randomized Controlled Trials

Background Chinese herbal medicines reportedly increase efficacy and minimize toxicity of chemotherapy; however, little attention has been paid to how poor study quality can bias outcomes. Methods We systematically searched MEDLINE, TCMLARS, EMBASE, and Cochrane Library for randomized controlled trials of Chinese herbal medicines combined with fluorouracil-based chemotherapy compared with the same chemotherapy alone. We screened for eligibility, extracted data, and pooled data with random-effects meta-analysis. Outcome measures were survival, toxicity, tumor response, performance status, quality of life, and Cochrane Risk of Bias (ROB) criteria to critically evaluate the quality of reporting in the randomized trials included in the meta-analysis. Results We found 36 potentially eligible studies, with only 3 (those with low ROB) qualifying for meta-analysis. Two reported chemotherapy-related diarrhea reduced by 57% (relative risk [RR] = 0.43; 95% CI = 0.19-1.01; I(2) test for variation in RR due to heterogeneity = 0.0%), with nonsignificant results. Two reported white blood cell toxicity reduced by 66% (RR = 0.34; 95% CI = 0.16-0.72; I(2) test for variation in RR due to heterogeneity = 0.0%), with statistically significant results. Stratifying analysis by studies with high versus low ROB, we found substantial overestimation of benefit: Studies with high ROB overestimated by nearly 2-fold reduction of platelet toxicity by Chinese herbal medicines (RR = 0.35, 95% CI = 0.15-0.84 vs RR = 0.65, 95% CI = 0.11-3.92). Studies with high ROB overestimated by nearly 2-fold reduction of vomiting toxicity (RR = 0.45, 95% CI = 0.33-0.61 vs RR = 0.87, 95% CI = 0.48-1.58). And, studies with high ROB overestimated by 21% the reduction in diarrhea toxicity (RR = 0.34, 95% CI = 0.20-0.58 vs RR = 0.43, 95% CI = 0.19-1.01). Studies with high ROB also overestimated by 16% improvement in tumor response (RR = 1.39, 95% CI = 1.18-1.63 vs RR = 1.20; 95% CI = 0.81-1.79). Not accounting for ROB would have exaggerated evidence of benefit and failed to detect nonsignificance of results. Conclusions In the present analysis, involving 36 studies, 2593 patients, 20 outcomes, 36 medical institutions, and 271 named research authors, 92% of the data points were from studies at high ROB. Given the poor quality of the data in studies identified, it cannot be concluded whether combining Chinese herbs with chemotherapy reduces toxicity of chemotherapy.

Mechanisms of drug resistance in colon cancer and its therapeutic strategies

Drug resistance develops in nearly all patients with colon cancer, leading to a decrease in the therapeutic efficacies of anticancer agents. This review provides an up-to-date summary on over-expression of ATP-binding cassette (ABC) transporters and evasion of apoptosis, two representatives of transport-based and non-transport-based mechanisms of drug resistance, as well as their therapeutic strategies. Different ABC transporters were found to be up-regulated in colon cancer, which can facilitate the efflux of anticancer drugs out of cancer cells and decrease their therapeutic effects. Inhibition of ABC transporters by suppressing their protein expressions or co-administration of modulators has been proven as an effective approach to sensitize drug-resistant cancer cells to anticancer drugs in vitro. On the other hand, evasion of apoptosis observed in drug-resistant cancers also results in drug resistance to anticancer agents, especially to apoptosis inducers. Restoration of apoptotic signals by BH3 mimetics or epidermal growth factor receptor inhibitors and inhibition of cancer cell growth by alternative cell death pathways, such as autophagy, are effective means to treat such resistant cancer types. Given that the drug resistance mechanisms are different among colon cancer patients and may change even in a single patient at different stages, personalized and specific combination therapy is proposed to be more effective and safer for the reversal of drug resistance in clinics.

Bevacizumab reduced auto-phosphorylation of VEGFR2 to protect HDM-induced asthma mice

Vascular endothelial growth factor (VEFG) is a major angiogenic factor involved in both normal physiological processes, such as embryonic development and wound healing, and in diseases, like cancer. Recent studies have revealed the functions of VEGF in inflammation and immunoregulation. Asthma is a chronic inflammation of the airways characterized by airway epithelial barrier dysfunction and imbalance in T-helper (Th) 1/Th2 during immunoregulation. We hypothesized that VEGF plays an important role in asthma. Utilizing a house dust mite extract (HDM)-induced murine model of asthma, we investigated whether bevacizumab, a humanized anti-VEGF monoclonal antibody, could protect the epithelial barrier in murine airways. We found that bevacizumab reduced airway hyper-responsiveness (AHR) and airway inflammation induced by HDM. In addition, HDM exposure promoted expression of VEGF, and caused AHR, disruptions of the epithelial barrier, and airway inflammation. Bevacizumab ameliorated AHR and the release of Th2 cytokines, thereby protecting the epithelial barrier. Our data suggest that bevacizumab may be a new therapeutic strategy for asthma.

Interaction effects on cytochrome P450 both in vitro and in vivo studies by two major bioactive xanthones from Halenia elliptica D. Don

The major components, 1-hydroxy-2,3,5-trimethoxy-xanthone (HM-1) and 1,5-dihydroxy-2,3-dimethoxy-xanthone (HM-5) isolated from Halenia elliptica D. Don (Gentianaceae), could cause vasodilatation in rat coronary artery with different mechanisms. In this work, high-performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LCMS-IT-TOF) was used to clarify the metabolic pathways, and CYP450 isoform involvement of HM-1 and HM-5 were also studied in rat. At the same time, in vivo inhibition effects of HM-1 and ethyl acetate extracts from origin herb were studied. Three metabolites of HM-5 were found in rat liver microsomes (RLMs); demethylation and hydroxylation were the major phase I metabolic reactions for HM-5. Multiple CYP450s were involved in metabolism of HM-1 and HM-5. The inhibition study showed that HM-5 inhibited Cyp1a2, 2c6 and 2d2 in RLMs. HM-1 inhibited activities of Cyp1a2, Cyp2c6 and Cyp3a2. In vivo experiment demonstrated that both HM-1 and ethyl acetate extracts could inhibit Cyp3a2 in rats. In conclusion, the metabolism of xanthones from the origin herb involved multiple CYP450 isoforms; in vitro, metabolism of HM-5 was similar to that of its parent drug HM-1, but their inhibition effects upon CYP450s were different; in vivo, Cyp3a2 could be inhibited by HM-1 and ethyl acetate extracts.

Silver nanoparticles defeat p53-positive and p53-negative osteosarcoma cells by triggering mitochondrial stress and apoptosis

Loss of function of the tumour suppressor p53 observed frequently in human cancers challenges the drug-induced apoptotic elimination of cancer cells from the body. This phenomenon is a major concern and provides much of the impetus for current attempts to develop a new generation of anticancer drugs capable of provoking apoptosis in a p53-independent manner. Since silver nanoparticles (AgNPs) possess unique cytotoxic features, we examined, whether their activity could be exploited to kill tumour suppressor-deficient cancer cells. Therefore, we investigated the effects of AgNPs on osteosarcoma cells of different p53 genetic backgrounds. As particle diameters might influence the molecular mechanisms leading to AgNP-induced cell death we applied 5 nm and 35 nm sized citrate-coated AgNPs. We found that both sized AgNPs targeted mitochondria and induced apoptosis in wild-type p53-containing U2Os and p53-deficient Saos-2 cells. According to our findings AgNPs are able to kill osteosarcoma cells independently from their actual p53 status and induce p53-independent cancer cell apoptosis. This feature renders AgNPs attractive candidates for novel chemotherapeutic approaches.