Synergistic antitumor effect of puerarin combined with 5-fluorouracil on gastric carcinoma

The Antitumor Potential of λ-Carrageenan Oligosaccharides on Gastric Carcinoma by Immunomodulation

Gastric carcinoma is a frequently detected malignancy worldwide, while its mainstream drugs usually result in some adverse reactions, including immunosuppression. λ-carrageenan oligosaccharides (COS) have attracted increasing attention as potential anticancer agents due to their ability to enhance immune function. Our current work assessed the antitumor mechanism of λ-COS using BGC-823 cells. Our findings indicated that λ-COS alone did not have a significant impact on BGC-823 cells in vitro; however, it was effective in inhibiting tumor growth in vivo. When THP-1 cells were pre-incubated with λ-COS and used to condition the medium, BGC-823 cells in vitro displayed a concentration-dependent induction of cell apoptosis, nuclear damage, and the collapse of mitochondrial transmembrane potential. These findings suggested that the antineoplastic effect of λ-COS was primarily due to its immunoenhancement property. Treatment with λ-COS was found to significantly enhance the phagocytic capability of macrophages, increase the secretion of TNF-α and IFN-γ, and improve the indexes of spleen and thymus in BALB/c mice. In addition, λ-COS was found to inhibit the growth of BGC-823-derived tumors in vitro by activating the Par-4 signaling pathway, which may be stimulated by the combination of TNF-α and IFN-γ. When used in combination with 5-FU, λ-COS demonstrated enhanced anti-gastric carcinoma activity and improved the immunosuppression induced by 5-FU alone. These findings suggested that λ-COS could be used as an immune-modulating agent for chemotherapy.

Antibiotic Combination Therapy: A Strategy to Overcome Bacterial Resistance to Aminoglycoside Antibiotics

After the first aminoglycoside antibiotic streptomycin being applied in clinical practice in the mid-1940s, aminoglycoside antibiotics (AGAs) are widely used to treat clinical bacterial infections and bacterial resistance to AGAs is increasing. The bacterial resistance to AGAs is owed to aminoglycoside modifying enzyme modification, active efflux pump gene overexpression and 16S rRNA ribosomal subunit methylation, leading to modification of AGAs' structures and decreased concentration of drugs within bacteria. As AGAs's side effects and bacterial resistance, the development of AGAs is time-consuming and difficult. Because bacterial resistance may occur in a short time after application in clinical practice, it was found that the antibacterial effect of the combination was not only better than that of AGAs alone but also reduce the dosage of antibiotics, thereby reducing the occurrence of side effects. This article reviews the clinical use of AGAs, the antibacterial mechanisms, the molecular mechanisms of bacterial resistance, and especially focuses a recent development of the combination of AGAs with other drugs to exert a synergistic antibacterial effect to provide a new strategy to overcome bacterial resistance to AGAs.

Deciphering the structure, function, expression and regulation of aquaporin-5 in cancer evolution

In recent years, the morbidity rate resulting from numerous types of malignant tumor has increased annually, and the treatment of tumors has been attracting an increasing amount of attention. A number of recent studies have revealed that the water channel protein aquaporin-5 (AQP5) has become a major player in multiple types of cancer. AQP5 is abnormally expressed in a variety of tumor tissues or cells and has multiple effects on certain biological functions of tumors, such as regulating the proliferation, apoptosis and migration of tumor cells. It has been suggested that AQP5 may play an important role in the process of tumor development, opening up a new field of tumor research. The present review highlighted the structure of AQP5 and its role in tumor progression. Furthermore, the expression of AQP5 in different malignant neoplasms was summarized. In addition, the influence of not only drugs, but also different compounds on AQP5 were summarized. In conclusion, according to the findings in the present review, AQP5 has potential as a novel therapeutic target in human cancer, and other AQPs should be similarly investigated.

Puerarin induces apoptosis in prostate cancer cells via inactivation of the Keap1/Nrf2/ARE signaling pathway

In this study, we examined the antitumor effects of Puerarin (PEU) on androgen-independent (DU145 and PC-3) and androgen-dependent (LNCaP) prostate cancer cells, and explored its potential mechanisms. Supplement with PEU (2.5 μM, 5 μM, and 10 μM) exhibited a marked inhibitory effect against the growth of DU145 and PC-3 cells, especially beyond 24 h, whereas there is only slight growth inhibitory effect on LNCaP cells at the high concentration of 10 μM at 72 h. This loss of cell viability in DU145 and PC-3 cells by PEU was mediated by the induction of apoptosis via up-regulation of Bax and cleaved-caspase-3, but downregulation of Bcl-2. Moreover, more intracellular ROS and LDH production were observed in DU145 and PC-3 cells upon PEU treatment. Meanwhile, the amount of pro-inflammatory cytokines (IL-1β and IL-6) was increased, but the content of anti-inflammatory cytokines IL-10 was attenuated. Additionally, PEU pretreatment resulted in an increase of Keap1 protein expression, and a decline of Nrf2, HO-1 and NQO1 protein expression in DU145 and PC3 cells. The present findings indicated that PEU exerted its antitumor activities toward androgen-independent prostate cancer cells via inactivation of Keap1/NrF2/ARE signaling pathway.

Puerarin 6″-O-xyloside suppressed HCC via regulating proliferation, stemness, and apoptosis with inhibited PI3K/AKT/mTOR

Puerarin 6″‐O‐xyloside is a tumor suppressive derivate of Puerarin that is recently characterized as a lysine‐specific demethylase 6B inhibitor. Here we investigated the effects of Puerarin 6″‐O‐xyloside in hepatocellular carcinoma (HCC) cell lines SMMC‐7721 and HepG2. Cell viability, proliferation, stemness, protein expression, and autophagy were tested by CCK‐8, colony formation, sphere formation, western blotting, and LC3B GFP puncta per cell, respectively. Apoptosis, CD133‐positive cells, and JC‐1‐labeled mitochondrial membrane potential were measured by flow cytometry. The effects of Puerarin 6″‐O‐xyloside in vivo were explored in HepG2 xenograft mice. Puerarin 6″‐O‐xyloside inhibited cell viability, proliferation, and stemness, and promoted apoptosis in both SMMC‐7721 and HepG2 cells. Further experiments showed promoted autophagy and decreased mitochondrial membrane potential, and decreased expression of p‐PI3K, p‐AKT, and p‐mTOR in HepG2 cells. Co‐administration of 3‐MA with Puerarin 6″‐O‐xyloside obviously augmented these effects including inhibited protein expression of p‐PI3K, p‐AKT, and p‐mTOR, and inhibited proliferation, promoted apoptosis, and decreased stemness. In HepG2 xenograft mice, 100 mg/kg/d Puerarin 6″‐O‐xyloside significantly suppressed tumor growth, stemness, and apoptosis. In conclusion, our study indicated that Puerarin 6″‐O‐xyloside decreased cell viability, proliferation, and stemness, and promoted autophagy and mitochondria‐dependent apoptosis of HCC, at least partly through inhibiting PI3K/AKT/mTOR. These results highlighted Puerarin 6″‐O‐xyloside as a promising prodrug that could inhibit both PI3K/AKT/mTOR and epigenetic demethylation.

A Critical Review on Anticancer Mechanisms of Natural Flavonoid Puerarin

Cancer is one of the prominent global causes of death and the foremost worldwide health concern. Despite unprecedented progress in cancer chemoprevention, a vast number of cancers, however, remain an undefeatable challenge for treatment modalities. Immense therapeutic activities of puerarin contribute to its use in various health disorders. In this review, we explored the potential molecular mechanisms and targets of puerarin, proving its potential as a novel anticancer agent, for future cancer therapy and chemoprevention. Several mechanisms account for anticancer activity of puerarin which includes downregulation of NF-kB signalling pathway, mTOR signalling pathway, PI3K and BCl-2 proteins and upregulation of miR-16, caspase proteins, c- Jun N terminal kinase and extracellular signal-regulated kinase 1/2. These alterations result in inhibition of cancer cell proliferation and/or induction of apoptosis. Understanding the molecular mechanisms involved in chemotherapy and chemoprevention could aid in the more pronounced exploration of puerarin in effective cancer treatment.

Extract of Cycas revoluta Thunb. enhances the inhibitory effect of 5-fluorouracil on gastric cancer cells through the AKT-mTOR pathway

BACKGROUND

Gastric cancer is one of the most common and deadly malignancies worldwide. Despite recent medical progress, the 5-year survival rate of gastric cancer is still unsatisfactory. 5-fluorouracil (5-Fu) is one of the first-line antineoplastic treatments for gastric cancer, as it can effectively induce cancer cell apoptosis. However, the effect of 5-Fu is limited due to drug resistance of the malignant tumor. Previous studies have reported that Sotetsuflavone from Cycas revoluta Thunb. can markedly suppress lung cancer cell proliferation by apoptosis, though its effect on gastric cancer remains unknown.

AIM

To investigate the inhibitory effect of Cycas revoluta Thunb. and to determine whether it can overcome gastric cancer cell drug resistance to 5-Fu.

METHODS

Cell viability was examined to determine whether the natural extract of Cycas revoluta Thunb. induced gastric cancer cell death. The half-maximal effective concentration and the half-maximal lethal concentration were calculatede. Wound-healing and transwell assays were performed to examine gastric cancer cell motility. Clonogenic assays were performed to investigate the synergistic effects of Cycas revoluta Thunb. with 5-Fu, and apoptotic bodies were detected by Hoechst staining. Western blotting was performed to examine the expression of related proteins and to investigate the molecular mechanism of Cycas revoluta Thunb.-induced cancer cell apoptosis. The expressions of proteins, including mammalian target of rapamycin (mTOR) and p-AKT, were detected in different combinations of treatments for 48 h, then analyzed by ECL detection.

RESULTS

Gastric cancer cells were more sensitive to the natural extract of Cycas revoluta Thunb. compared to normal gastric epithelial cells, and the extract effectively inhibited gastric cancer cell migration and invasion. The extract improved the anti-cancer effect of 5-Fu by enhancing the chemosensitization of gastric cancer cells. Extract plus 5-Fu further reduced the expression of the drug-resistance-related proteins p-AKT and mTOR after 48 h compared to 5-Fu alone. Compared to 5-Fu treatment alone, mTOR and p-AKT expression was significantly reduced by about 50% and 75%, respectively. We also found that the natural extract of Cycas revoluta Thunb. further increased 5-Fu-induced gastric cancer cell apoptosis. Expression of apoptosis-related protein X-linked inhibitor of apoptosis protein and apoptosis inducing factor were significantly reduced and increased, respectively, in the 5-Fu-resistant gastric cancer line SGC-7901/R treated with extract plus 5-Fu, while the expression of survivin did not change.

CONCLUSION

The natural extract of Cycas revoluta Thunb. effectively inhibited gastric cancer cell growth and enhanced the anti-cancer effect of 5-Fu through the AKT-mTOR pathway.

Effects of three flavonoids from an ancient traditional Chinese medicine Radix puerariae on geriatric diseases

As the worldwide population ages, the morbidity of neurodegenerative, cardiovascular, cerebrovascular, and endocrine diseases, such as diabetes and osteoporosis, continues to increase. The etiology of geriatric diseases is complex, involving the interaction of genes and the environment, which makes effective treatment challenging. Traditional Chinese medicine, unlike Western medicine, uses diverse bioactive ingredients to target multiple signaling pathways in geriatric diseases. Radix puerariae is one of the most widely used ancient traditional Chinese medicines and is also consumed as food. This review summarizes the evidence from in vivo and in vitro studies of the pharmacological effects of the main active components of the tuber of Radix puerariae on geriatric diseases.

Puerarin in inducing apoptosis of bladder cancer cells through inhibiting SIRT1/p53 pathway

Regulatory effect of puerarin on bladder cancer T24-cell apoptosis and its possible mechanism were investigated. The experimental subjects were divided into the experimental group, the control group and the blank control group, and the cell inhibition rates after treatment were detected, respectively. Then, subjects were further divided into the control group, the puerarin group (treated with puerarin), the agonist group [treated with silent information regulator 1 (SIRT1) agonist SRT1720], the inhibitor group (treated with SIRT1 inhibitor EX527) and the combination group (treated with SRT1720, and then with puerarin). Apoptosis in each group was detected via flow cytometry, and the expression of apoptosis-related proteins, and SIRT1 and p53 proteins in each group was detected via western blotting. Moreover, the expression of SIRT1 and p53 messenger ribonucleic acid (mRNA) was detected via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The inhibition rate of bladder cancer T24 cells was significantly increased after treatment with puerarin at different concentrations. Compared with those in the normal control group, the inhibition rates at 24, 48 and 72 h after treatment with puerarin were significantly increased (p<0.05). Compared with those in the control group, the apoptosis rate of T24 cells was remarkably increased after treatment with different doses of puerarin or EX527, and the expression level of apoptosis-related protein Bcl-2-associated X protein (Bax) was also significantly increased, but the expression level of B-cell lymphoma 2 (Bcl-2) was decreased, and both the protein and mRNA expression levels of SIRT1 and p53 also significantly declined. Compared with those in the puerarin group, the apoptosis rate in the combination group was decreased, and the expression level of apoptosis-related protein Bax was also significantly decreased, but the expression level of Bcl-2 was increased, and SIRT1 and p53 protein expression levels were also remarkably increased. Puerarin can inhibit the proliferation of bladder cancer T24 cells and induce apoptosis, and the possible mechanism is related to the inhibition of SIRT1/p53 signaling pathway.

Inhibitory effect of Gypsophila oldhamiana gypsogenin on NCI-N87 gastric cancer cell line

Gastric cancer is one of the major cancers threatening people’s lives worldwide. Recent studies showed that Gypsophila oldhamiana gypsogenin (GOG) exhibits inhibition effects and cytotoxic activities against different cell lines. The aim of this study was to explore the inhibitory effect and dose response of GOG on gastric cancer cell line NCI-N87 and to provide the theoretical basis for clinical anti-tumor therapy. The experiments showed that GOG could inhibit the proliferation and promote the apoptosis of human gastric cancer cell line NCI-N87. GOG could dose dependently reduce the expression of vascular endothelial growth factor (VEGF) and matrix metalloprotein (MMP)-9 proteins, while increase the expression of caspase-3 and Bax proteins. Compared with model group, tumor volume (TV), relative tumor volume (RTV), and relative tumor increment rate (T/C) in the mid-dose and high-dose GOG groups were significantly reduced, and the inhibition rate (IR) in the two groups was significantly increased. The results indicated that the anti-tumor effect of GOG on gastric cancer cells may be related with the downregulation of caspase-3 and Bax and the upregulation of MMP-9 and VEGF.

Puerarin inhibits bladder cancer cell proliferation through the mTOR/p70S6K signaling pathway

Puerarin, as a novel oncotherapeutic agent, may exert anticancer effects and inhibit the proliferation of cancer cells. To explore the effects of puerarin on human bladder cancer cells, and to elucidate the potential mechanism underlying these effects, a Cell Counting Kit-8 assay was used to examine the proliferation of T24 and EJ cells following puerarin treatment. The effects of puerarin treatment on the cell cycle were detected by flow cytometry (FCM), while puerarin-induced cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling and FCM, and the cellular ultrastructural morphological changes were observed by transmission electron microscopy. Cell invasion was examined using a Transwell assay with Matrigel. The expression levels of mechanistic target of rapamycin (mTOR), phosphorylated (p)-mTOR, p70-S6 kinase (p70S6K) and p-p70S6K proteins in the mTOR signaling pathway were then assessed by western blotting. The results demonstrated that puerarin may inhibit bladder cancer cell viability, block the cell cycle in the G0/G1 phase and induce apoptosis in bladder cancer cells. The expression levels of p-mTOR and p-p70S6K proteins were downregulated, while no change was observed in the expression levels of mTOR and p70S6K proteins when T-24 and EJ cells were treated by puerarin. In the present study, puerarin was demonstrated to inhibit the viability of human bladder cancer cells. These effects may be due to the puerarin-induced downregulation of proteins in the mTOR/p70S6K signaling pathway, and the present study may provide the experimental basis for puerarin to be considered as a promising novel anti-tumor drug for the treatment of bladder cancer.

Trifluridine/tipiracil increases survival rates in peritoneal dissemination mouse models of human colorectal and gastric cancer

A number of patients exhibit peritoneal dissemination of gastric or colorectal cancer, which is a predominant cause of cancer-associated mortality. Currently, there is no markedly effective treatment available. The present study was designed to determine the efficacy of trifluridine/tipiracil (TFTD), formerly known as TAS-102, which is used for the treatment of patients with unresectable advanced or recurrent colorectal cancer refractory to standard therapies. Four colorectal cancer cell lines and one gastric cancer cell line were intraperitoneally inoculated into nude mice, as models of peritoneal dissemination. TFTD (200 mg/kg/day) was orally administered for 5 consecutive days followed by 2 drug-free days for 6 weeks. The increase in the lifespan (ILS) of the TFTD-treated mice compared with that of the drug-free control mice was 66.7, 43.3, 106.3, 98.3 and 133.3% for DLD-1, DLD-1/5-fluorouracil [5-fluorouracil (5FU)-resistant subline of DLD-1], HT-29 and HCT116 colorectal cancer cell lines, and MKN45 gastric cancer cell line, respectively. This ILS was similar to that of the irinotecan-treated mice (ILS, 70–84%), but was significantly (P<0.05) increased compared with that of the 5FU-, tegafur, gimeracil and potassium oxonate- and cisplatin-treated mice (ILS, 1–53%, 0.8–60% and 85%, respectively). No significant increase in body weight loss was observed during the dosing periods with any of the drugs used. The increase in CEA levels with progressive peritoneal dissemination was inhibited by TFTD treatment. TFTD also exhibited marked anticancer effects against Kirsten rat sarcoma viral oncogene homolog-mutated tumors and 5FU-resistant tumors. The results of the present study indicate that TFTD may be a potential drug against peritoneal dissemination of colorectal and/or gastric cancer in humans and may be utilized for chemo-naïve tumors and recurrent tumors following 5FU treatment.

Aquaporins: New Targets for Cancer Therapy

Aquaporins are a family of integral membrane proteins that are expressed in all living organisms and play vital roles in transcellular and transepithelial water movement. Cell viability and motility are critical for progression of cancer. Cell survival requires the suitable concentration of water and solutes. The balance is largely maintained by aquaporins whose major function is the transport of water and small solutes across the plasma membrane. The important role of aquaporins has received more and more attention in the recent years. A number of recent studies have revealed that aquaporins may be involved in cell migration and angiogenesis. This review will highlight the expression of aquaporins in different malignant neoplasms. Remarkably, we will summarize the influence of drugs on aquaporins, not only the traditional Chinese medicine but also the Western medicine. Therapeutic targeting of aquaporins may thus be advantageous for blocking the mechanism common for a number of key cancer phenotypes.