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Most cancer therapies are suffering from side effects to varying degrees, which might compromise the body functions and long-term health of patients. Balancing treatment efficacy and side effects has become a priority. Inspired by the concept that cellular ion homeostasis can lead to apoptosis, we developed a novel therapeutic strategy by incorporating the K+ transporter valinomycin into liposomes (Lipo-VM). Valinomycin is a naturally occurring polypeptide showing good biodegradation in vivo with reduced long-term side effects. Lipo-VM facilitates the K+ efflux of cells and triggers a caspase-dependent pathway of apoptosis by causing the collapse of mitochondrial membrane potential. With the help of a liposome-based nano-delivery system, Lipo-VM shows enhanced cell uptake and accumulation at the tumor site, which results in significant inhibition of tumor growth in a liver cancer model. The proposed valinomycin-anchored liposome provides an efficient and safe approach for cancer therapy.

Saikosaponin A (SSA)-a natural compound extracted from Radix bupleuri-possesses antitumor properties in several types of carcinomas. However, the role of SSA on bladder cancer and the mechanisms remain unclear. In this study, we have described the effect of SSA on human bladder cancer cell lines T24 and 5637 in the context of the regulation of mitochondrial pathways of apoptosis. In vitro, the Cell Counting Kit-8 (CCK-8) assay and cell wound healing assays were used to determine the proliferative effect of SSA treatment. Flow cytometry and Western blotting were performed to evaluate the apoptosis and related mechanisms. To further confirm that apoptosis is mediated through Caspase activation, Hoechst 33258 fluorescence staining assay was done after cells were treated with SSA and caspase inhibitor-Z-VAD-FMK. In vivo, an orthotopic xenograft mice model was adopted to evaluate the effect of SSA. The tumors were analyzed by hematoxylin-eosin (HE) staining, immunohistochemical analysis, and Western blotting. In vitro, the results with CCK-8 assay showed obvious SSA-induced suppression in cell growth in a dose- and time-dependent manner. Flow cytometry analysis, Hoechst 33258 fluorescence staining assay and the assessment of the changes in the B-cell lymphoma 2 (Bcl-2) family protein expression level revealed that SSA could significantly induce cell apoptosis, which was associated with apoptosis via the mitochondrial pathways. In vivo, the results revealed a reduction in cell proliferation. In conclusion, our data suggest that SSA inhibits the growth of bladder cancer cells by activating the mitochondrial apoptosis pathway and inducing cell apoptosis.

Backgrounds A major side effect of statin, a widely used drug to treat hyperlipidemia, is skeletal myopathy through cell apoptosis. The aim of this study is to investigate the roles of microRNA in statin-induced injury. Methods Apolipoprotein E knockout (ApoE-/-) mice were administered with simvastatin (20 mg/kg/day) for 8 weeks. Exercise capacity was evaluated by hanging grid test, forelimb grip strength, and running tolerance test. Results In cultured skeletal muscle cells, statin increased the levels of miR-1a but decreased the levels of mitogen-activated protein kinase kinase kinase 1 (MAP3K1) in a time or dose dependent manner. Both computational target-scan analysis and luciferase gene reporter assay indicated that MAP3K1 is the target gene of miR-1a. Statin induced cell apoptosis of skeletal muscle cells, but abolished by downregulating of miR-1a or upregulation of MAP3K1. Further, the effects of miR-1a inhibition on statin-induced cell apoptosis were ablated by MAP3K1 siRNA. In ApoE-/- mice, statin induced cell apoptosis of skeletal muscle cells and decreased exercise capacity in mice infected with vector, but not in mice with lentivirus-mediated miR-1a gene silence. Conclusion Statin causes skeletal injury through induction of miR-1a excessive expression to decrease MAP3K1 gene expression.

Tongguanteng injection (TGT), the water extract from the stem of the Traditional Chinese hebal medicine of Marsdenia tenacissima (Roxb.) Wight et Arn. has been used as anticancer remedy for decades. TGT was not only used in the treatment of many malignant cancers extensively, but also an adjuvant anticancer drug with chemotherapeutics clinically.To evaluate the effects of TGT on reversing paclitaxel (PTX) resistance and investigate the potential mechanism related to TAB1 in ovarian cancer (OC) in vitro and in vivo.The synergistic effect and reversal ratio were determined by CCK8 assay and median-effect principle after the combination of TGT and PTX in OC A2780 and its PTX-resistant (A2780/T) cells. The biological functions in cell apoptosis, migration and invasion of A2780/T cells treated by PTX 4 μM with TGT 20, 40, 80 mg⋅mLTGT combined with PTX showed the synergistic effect (CI1), which could reverse the ICOur results revealed that Tongguanteng injection could reverse paclitaxel resistance and the potential mechanism might be associated with the activation of TAB1/TAK1/p38 MAPK signaling pathway in OC in vitro and in vivo. TAB1 might be a pivotal target for reversing PTX resistance. This study will provide a theoretical basis for the combination of Tongguanteng injection and paclitaxel in clinic.

Lung cancer is the most common malignancy and the leading cause of cancer death worldwide, and lung adenocarcinoma (LUAD) is the most prevalent subtype. Considering the emergence of resistance to therapies, it is urgent to develop more effective therapies to improve the prognosis. Here we reported that pancreatic progenitor cell differentiation and proliferation factor (PPDPF) deficiency inhibited LUAD development both in vitro and in vivo. Mechanistically, PPDPF induces hyperactive STAT3 by interfering STAT3-PTPN1 interaction. Activated STAT3 promoted BMPR2 transcription, which further inhibited apoptosis. Moreover, PPDPF reduced NK cell infiltration and activation to develop an immunosuppressive microenvironment, which was also mediated by STAT3. Furthermore, we identified that the expression of PPDPF was positively correlated with the malignant features of LUAD, as well as BMPR2 and p-STAT3 level in clinical samples. Therefore, our study suggests that PPDPF positively regulates BMPR2 expression and facilitates immune escape via regulating STAT3 activity, providing a potential therapy target for LUAD.

Dihydroartemisinin (DHA) is a potent anti-cancer drug that has limited clinical applications due to poor water solubility and low bioavailability. We designed a biodegradable poly(ethylene glycol) methyl ether-poly(ε-caprolactone) (MPEG-PCL) micelle carrier for DHA using the self-assembly method. The DHA/MPEG-PCL nanoparticles were spherical with an average particle size of 30.28 ± 0.27 nm, and released the drug in a sustained manner in aqueous solution. The drug-loaded nanoparticles showed dose-dependent toxicity in HeLa cells by inducing cycle arrest and apoptosis. Furthermore, compared to free DHA, the DHA/MPEG-PCL nanoparticles showed higher therapeutic efficacy and lower toxicity in vivo, and significantly inhibited tumor growth and prolonged the survival of tumor-bearing nude mice. In addition, the tumor tissues of the DHA/MPEG-PCL-treated mice showed a marked decline in the in situ expression of proliferation and angiogenesis markers. Taken together, the self-assembled DHA/MPEG-PCL nanoparticles are a highly promising delivery system for targeted cancer treatment.

Inducing homologous recombination (HR) deficiency is a promising strategy to broaden the indication of PARP1/2 inhibitors in pancreatic cancer treatment. In addition to inhibition kinases, repression of the transcriptional function of FOXM1 has been reported to inhibit HR-mediated DNA repair. We found that FOXM1 inhibitor FDI-6 and PARP1/2 inhibitor Olaparib synergistically inhibited the malignant growth of pancreatic cancer cells in vitro and in vivo. The results of bioinformatic analysis and mechanistic study showed that FOXM1 directly interacted with PARP1. Olaparib induced the feedback overexpression of PARP1/2, FOXM1, CDC25A, CCND1, CDK1, CCNA2, CCNB1, CDC25B, BRCA1/2 and Rad51 to promote the acceleration of cell mitosis and recovery of DNA repair, which caused the generation of adaptive resistance. FDI-6 reversed Olaparib-induced adaptive resistance and inhibited cell cycle progression and DNA damage repair by repressing the expression of FOXM1, PARP1/2, BUB1, CDC25A, BRCA1 and other genes-involved in cell cycle control and DNA damage repair. We believe that targeting FOXM1 and PARP1/2 is a promising combination therapy for pancreatic cancer without HR deficiency.

Abnormal expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 4 (PFKFB4) is closely related to the occurrence and development of tumors, and PFKFB4 has been shown to function as a protein kinase. However, the molecular mechanisms through which PFKFB4 functions in glioblastoma (GBM) remain poorly understood. Accordingly, in this study, we assessed the roles of PFKFB4 in GBM. Compared to in adjacent tissues, PFKFB4 was highly expressed in GBM, and its expression level was negatively correlated with the overall survival time. In addition, knockdown of PFKFB4 inhibited the proliferation and invasion of GBM cells and promoted apoptosis. In a xenograft tumor model, tumor growth was inhibited by knockdown of PFKFB4 using short hairpin RNA. Further studies demonstrated that PFKFB4 is involved in regulating the AKT signaling pathway. Thus, PFKFB4 acts as a protein kinase to regulate GBM progression by activating the AKT/forkhead box O1 pathway, which may be a potential therapeutic target in GBM.

Diet and exercise are the most effective approaches used to induce weight loss. D‑psicose is a low‑calorie sweetener that has been shown to reduce weight in obese individuals. However, the effect of D‑psicose on muscle cells under oxidative stress, which is produced during exercise, requires further investigation. The present study aimed to determine the effects of D‑psicose on C2C12 myogenic cells in vitro. Hydrogen peroxide (H2O2) was used to stimulate the generation of intracellular reactive oxygen species (ROS) in muscle cells to mimic exercise conditions. Cell viability was analyzed using a MTT assay and flow cytometry was used to analyze the levels of apoptosis, mitochondrial membrane potential (MMP), the generation of ROS and the cell cycle distribution following treatment. Furthermore, protein expression levels were analyzed using western blotting and cell proliferation was determined using a colony formation assay. The results of the present study revealed that D‑psicose alone exerted no toxicity on C2C12 mouse myogenic cells. However, in the presence of low‑dose (100 µM) H2O2‑induced ROS, D‑psicose induced C2C12 cell injury and significantly decreased C2C12 cell viability in a dose‑dependent manner. In addition, the levels of apoptosis and the generation of ROS increased, while the MMP decreased. MAPK family molecules were also activated in a dose‑dependent manner following treatment. Notably, the combined treatment induced G2/M phase arrest and reduced the proliferation of C2C12 cells. In conclusion, the findings of the present study suggested that D‑psicose may induce toxic effects on muscle cells in a simulated exercise situation by increasing ROS levels, activating the MAPK signaling pathway and disrupting the MMP.

Acute myeloid leukemia (AML) is a malignant cancer of the hematopoietic system. Although the effectiveness of arsenic compounds has been recognized and applied clinically, some patients are still found resistant to this chemotherapy. In this study, we investigated that a synthetic thyroid hormone analog (TA), 2-iodo-4-nitro-1-(o-tolyloxy) benzene, had a strong apoptosis effect on U937 cells. U937 cells were treated with TA, and examinted the generation of reactive oxygen species (ROS), dysfunction of mitochondria, expression of pro-apoptosis and anti-apoptosis, and cleavage of caspase-3 and Poly (ADP-ribose) polymerase (PARP). Further, it is also evaluated that insight molecular mechanism and signaling pathways involved in the study. It is found that TA significantly induced apoptosis in U937 cells through production of ROS, dysfunction of mitochondria, and activation of caspase cascade. It was also observed that MAPK signaling pathway including ERK, JNK, and P38 signals are involved in the induction of apoptosis. Moreover, marked activation of autophagy and ER stress markers such as LC3, P62, Beclin1 and GRP78, CHOP were observed, respectively. Pretreatment with ER stress inhibitor tauroursodeoxycholic acid (TUDCA) and autophagy inhibitor 3-Methyladenine (3-MA) have successfully attenuated and aggravated TA-induced apoptosis, respectively. We further confirmed the active involvement of ER stress and autophagy signals. In conclusion, TA induced apoptosis through ER stress and activation of autophagy, and the latter is not conducive to TA-induced cell death. Our results may provide a new insight into the strategic development of novel therapy for the treatment of AML.

Melatonin, a safe endogenous hormone and a natural supplement, has recently been recognized to have antiproliferative effects and the ability to sensitize cells to other anticancer therapies. Phenylarsine oxide (PAO) has anticancer potential but it is considered as a toxic agent. In this study we combined melatonin to reduce the toxicity while securing the anti-cancer effects of PAO. Cell viability was determined by MTT assay, whereas cytotoxic assays were performed using an LDH cytotoxicity assay kit. Cell cycle analysis, Annexin V/PI staining, the mitochondrial membrane potential (MMP), mitochondrial calcium and reactive oxygen species (ROS) generation were analyzed using flow cytometry. Sytox stained cells were visualized by fluorescence microscopy and the expression of proteins was detected by western blotting. Melatonin increased the anticancer potential of PAO by decreasing the cell viability and increasing LDH release in various cancer cells. The mode of cell death was determined to be typical apoptosis, as evidenced by Annexin V/PI-stained cells, PARP cleavage, and caspase-3 activation, and with significant modulations in the expression of proapoptotic, antiapoptotic and cell cycle-related proteins. ROS generation played a critical role in induction of cell death by this combined treatment, which is validated by reversal of cytotoxicity upon cotreatment with NAC. Furthermore, the activation of MAPKs, especially JNK, contributed to the induction of cell death, accompanied by endoplasmic reticulum stress and autophagy, affirmed by the abrogation of cytotoxicity after JNK-IN-8 and TUDCA application. Melatonin showed promising potential as a chemotherapeutic agent in combination with PAO to achieve a better anticancer response.

Ethnopharmacological relevance Xiaoaiping injection, a traditional Chinese medical injection extracted from root of Marsdenia tenacissima (Roxb.) Moon, has been exclusively used on curing malignant tumor in China and as adjuvant therapeutic agent for chemotherapeutics, including paclitaxel. Aim of the study The goal of this study was to investigate the synergistic inhibitory efficacy of Xiaoaiping injection and paclitaxel on ovarian cancer. The mechanism may be associated with nuclear receptor pregnane X receptor (PXR) regulating its downstream molecules. Materials and methods In vitro, MTT assay, flow cytometry and Hoechst dyeing were used to evaluate the SK-OV-3 cell proliferation, apoptosis and cell cycle respectively. The mRNA and protein expression of PXR and its downstream CYP450 enzymes, transporters and Bcl-2 families were measured by qRT-PCR and Western blot. Rhodamine 123 efflux experiment was conducted to detect the P-gp efflux ability. PXR plasmid and PXR siRNA were transiently transfected into SK-OV-3 cells respectively to establish PXR-overexpressed or PXR-interfered cells. In vivo, xenograft tumor mice model was established by SK-OV-3 cells to estimate the antitumor effect of Xiaoaiping injection combined with paclitaxel. The expressions of PXR and its downstream molecules in tumor tissues were determined to further clarify the potential mechanism. Results Xiaoaiping injection significantly enhanced the anti-proliferation, pro-apoptosis effect of paclitaxel on SK-OV-3 cells. The synergetic effect was displayed by Xiaoaiping injection inhibiting paclitaxel-induced PXR and CAR expression, which subsequently inhibited CYP450 enzymes CYP2C8 and CYP3A4, transporter P-gp and anti-apoptotic proteins Bcl-2 and Bcl-xl in SK-OV-3 cells. In PXR-overexpressed cells, Xiaoaiping injection down-regulated the expression of PXR and its downstream molecules. The result of xenograft tumor model showed that Xiaoaiping injection combined with paclitaxel enhanced anti-tumor effect on ovarian cancer in vivo. Conclusions Xiaoaiping injection enhances anti-tumor effect of paclitaxel by inhibiting cell proliferation, inducing apoptosis process. The mechanism may be associated with Xiaoaiping injection inhibiting PXR and its downstream metabolic enzymes CYP2C8, CYP3A4, transporter P-gp and anti-apoptosis protein Bcl-2.

Hepatocellular carcinoma (HCC) is one of the most deadly cancers worldwide that responds poorly to existing therapies. The Casein kinase 1 (CK1) isoforms CK1δ and CK1e are reported to be highly expressed in several tumor types, and both genetic and pharmacological inhibition of CK1δ/e activity has deleterious effects on tumor cell growth. IC261, an CK1δ/e selectively inhibitor, shows anti-tumor effect against pancreatic tumor and glioblastoma, but its role in HCC remains poorly characterized. In our research, IC261 displayed time- and dose-dependent inhibition of HCC cell proliferation, and induced G2/M arrest and cell apoptosis in vitro. However, the anti-tumor effects of IC261 was independent of CK1δ/e. Additionally, IC261 was verified to induce centrosome fragmentation during mitosis independent of CK1δ status, and intraperitoneal injection of IC261 to HCCLM3 xenograft models inhibited tumor growth. Taken together, our data indicated that IC261 has therapeutic potential for HCC.

Hyperthermia is one therapeutic tool for damaging and killing cancer cells, with minimal injury to normal tissues. However, its cytotoxic effects alone are insufficient for quantitative cancer cell death. To overcome this limitation, several studies have explored non-toxic enhancers for hyperthermia-induced cell death. Capsaicin may be applicable as a therapeutic tool against various types of cancer. In the present study, we employed nonivamide, a less-pungent capsaicin analogue, to investigate its possible enhancing effects on hyperthermia-induced apoptosis; moreover, we analyzed its molecular mechanism. Treatment of U937 cells at 44 °C for 15 min, combined with nonivamide 50 μM, revealed enhancement of apoptosis. Significant increases in reactive oxygen species generation, mitochondrial dysfunction, and cleaved caspase-3 were observed during the combined treatment; these were accompanied by an increase in pro-apoptotic Bcl-2 family proteins and a decrease in anti-apoptotic Bcl-2 proteins. In addition, significant increases in p-JNK and p-p38 were detected, following the combined treatment. In conclusion, nonivamide enhanced hyperthermia-induced apoptosis via a mitochondrial-caspase dependent pathway. The underlying mechanism may include elevation of intracellular reactive oxygen species, mitochondrial dysfunction, and increased activation of JNK and p38.

During the past two decades, cytokines have emerged as key molecules to modulate innate and adaptive immunity and mediate anti-tumor activity. Although multiple cytokine types are implicated for such anti-tumor activity in several cancer types, it remains largely unknown in breast cancer. In this study, cytokines that are prior known for antitumor activity in different cancer types were examined against breast cancer using a 4T1 cells based xenograft-model. Our results showed Interleukin-12 (IL-12) (500ng/mouse) significantly suppressed the growth of tumors, while other cytokines showed minimal suppression. Subsequent molecular analysis by flow cytometry and immunohistochemistry confirmed the CD8+ cells infiltration and Interferon-γ (IFN-γ) production by them in tumor environment. In addition, we observed that IFN-γ production by activated CD8+ cells directly induced apoptosis in tumor cells, which together indicate that IL-12 causes CD8+ cells to infiltrate and secrete IFN-γ in tumor environment, which induce apoptosis in them and causes tumor growth suppression. Furthermore, we showed that lower dosage of IL-12 and chemotherapy drug tamoxifen combinations enhanced the tumor suppression as opposed to single treatments, and thereby propose an alternate option for high dosage associated effects for both drug and cytokine treatments.

Dihydromyricetin (DMY) is a traditional herbal medicine, with a wide range of biological activities. Extreme hyperthermia (HT) can suppress the immune system; thus, protection of the immune system is beneficial in heat-related diseases, including heatstroke. In our study, we revealed the protective effect of DMY against HT-induced apoptosis and analysed the underlying molecular mechanisms. We incubated human myelomonocytic lymphoma U937 cells at 44 °C for 30 min with or without DMY and followed by further incubation for 6 h at 37 °C. Cell viability was determined by the CCK-8 assay. DMY did not cause any cytotoxic effects in U937 cells even at high doses. HT treatment alone induced significant apoptosis, which was detected by DNA fragmentation and Annexin V/PI double staining. Mitochondrial dysfunction was identified by loss of mitochondrial membrane potential (MMP) during heat stimulation. Apoptotic related proteins were involved, truncated Bid and caspase-3 were upregulated, and Mcl-1 and XIAP were downregulated. We also identified the related signalling pathways, such as the MAPK and PI3K/AKT pathways. However, changes in HT were dramatically reversed when the cells were pretreated with DMY before exposure to HT. Overall, MAPKs and PI3K/AKT signalling, mitochondrial dysfunction, and caspase-mediated pathways were involved in the protective effect of DMY against HT-induced apoptosis in U937 cells, which was totally reversed by DMY pretreatment. These findings indicate a new clinical therapeutic strategy for the protection of immune cells during heatstroke.

Chemoresistance is one of the major obstacles in chemotherapy-based hepatocellular carcinoma (HCC) intervention. Aluminum (Al) is an environmental pollutant that plays a vital role in carcinogenesis, tumorigenesis, and metastasis. However, the effect of Al on chemoresistance remains unknown. 5-Fluorouracil (5-FU) is a widely used antitumor drug. Therefore, we investigated the effects of aluminum chloride (AlCl3 ) on the chemoresistance of HepG2 cells to 5-FU and explored the underlying mechanisms of these effects. The results demonstrated that AlCl3 pretreatment attenuated 5-FU-induced apoptosis through Erk activation and reversed 5-FU-induced cell cycle arrest by downregulating p-Chk2Thr68 levels. In addition, AlCl3 markedly increased the levels of proteins associated with cell migration, such as MMP-2 and MMP-9. Further investigation demonstrated that an Erk inhibitor (U0126) reversed the AlCl3 -induced decrease in apoptosis, enhancement of cell cycle progression, promotion of cell migration, and attenuation of oxidative stress. In summary, AlCl3 induced chemoresistance to 5-FU in HepG2 cells. The present study suggests a potential influence of AlCl3 on 5-FU therapy. These findings may help others to understand and properly address the resistance of HCC to chemotherapeutic agents.

Atropine, a widely used topical anticholinergic drug, might have adverse effects on human corneas in vivo. However, its cytotoxic effect on human corneal endothelium (HCE) and its possible mechanisms are unclear. Here, we investigated the cytotoxicity of atropine and its underlying cellular and molecular mechanisms using an in vitro model of HCE cells and verified the cytotoxicity using cat corneal endothelium (CCE) in vivo. Our results showed that atropine at concentrations above 0.3125 g/L could induce abnormal morphology and viability decline in a dose- and time-dependent manner in vitro. The cytotoxicity of atropine was proven by the induced density decrease and abnormality of morphology and ultrastructure of CCE cells in vivo. Meanwhile, atropine could also induce dose- and time-dependent elevation of plasma membrane permeability, G1 phase arrest, phosphatidylserine externalization, DNA fragmentation, and apoptotic body formation of HCE cells. Moreover, 2.5 g/L atropine could also induce caspase-2/-3/-9 activation, mitochondrial transmembrane potential disruption, downregulation of anti-apoptotic Bcl-2 and Bcl-xL, upregulation of pro-apoptotic Bax and Bad, and upregulation of cytoplasmic cytochrome c and apoptosis-inducing factor. In conclusion, atropine above 1/128 of its clinical therapeutic dosage has a dose- and time-dependent cytotoxicity to HCE cells in vitro which is confirmed by CCE cells in vivo, and its cytotoxicity is achieved by inducing HCE cell apoptosis via a death receptor-mediated mitochondrion-dependent signaling pathway. Our findings provide new insights into the cytotoxicity and apoptosis-inducing effect of atropine which should be used with great caution in eye clinic.

Atropine is an anticholinergic drug for mydriasis in eye clinic, and its abuse might be cytotoxic to the cornea and result in blurred vision. However, the cytotoxicity of atropine to the cornea and its cellular and molecular mechanisms remain unknown. In this study, we investigated the cytotoxicity of atropine to corneal epithelium and its underlying mechanisms using an in vitro model of non-transfected human corneal epithelial (HCEP) cells. Our results showed that atropine, above the concentration of 0.3125 g/l (1/32 of its therapeutic dosage in eye clinic), had a dose- and time-dependent toxicity to HCEP cells by inducing morphological abnormality, cytopathic effect, viability decline, and proliferation retardation. Moreover, the proliferation-retarding effect of atropine on the cells was achieved by inducing G1/S phase arrest and downregulation of E-cadherin and β-catenin. Besides, atropine also had an apoptosis-inducing effect on the cells by inducing phosphatidylserine externalization, plasma membrane permeability elevation, DNA fragmentation and apoptotic body formation. Furthermore, atropine could also induce activations of caspase-2, -3 and -9, disruption of mitochondrial transmembrane potential, downregulation of Bcl-2 and Bcl-xL, upregulation of Bax and Bad, and upregulation of cytoplasmic cytochrome c and apoptosis-inducing factor, implying a death receptor-mediated mitochondrion-dependent pathway is most probably involved in the apoptosis of HCEP cells induced by atropine. Taken together, our results suggest that atropine has remarkable cytotoxicity to HCEP cells by inducing cell cycle arrest and death receptor-mediated mitochondrion-dependent apoptosis.

Hederagenin is a naturally occurring pentacyclic triterpenoids compound with multiple pharmacological activities. We recently showed that H6, a synthetic derivative of hederagenin, could enhance the anticancer activity of paclitaxel in drug-resistant cells in vitro and in vivo, but showed poor solubility. With the aim of improving the drug resistant reversal activity of H6, here we designed and synthesized a series of novel H6 analogues. Our results showed that compound 10 at the concentration of 5 μM significantly enhanced the cytotoxicity of paclitaxel to drug-resistant KBV cells and sensitized cells to paclitaxel in arresting cells in G2/M phase and inducing apoptosis. We found that compound 10 might block the drug efflux of P-gp via stimulating P-gp ATPase activity. Importantly, compound 10 enhanced the efficacy of paclitaxel against KBV cancer cell-derived xenograft tumors. Finally, we summarized a preliminary structure-activity relationship of hederagenin by the drug resistant reversal activity of H6 analogues in vitro and compound 10 and H6 in vivo. This study highlights the importance of nitrogen-containing derivatives of hederagenin C-28 in the development of novel drug resistance reversal agents.

BACKGROUND Hyperthermia (HT) has been used widely for cancer therapy, and the development of modern devices has made it more efficient. Shikonin (SHK) is a natural naphthoquinone derivative from a Chinese herb. Although the anticancer properties of SHK are evident, the underlying molecular mechanisms are not fully understood. OBJECTIVE In this study, the effects of combining low doses of SHK with mild HT were investigated in the U937 cell line. METHODS The cells were subjected to HT at 44°C for 10 min with or without SHK pretreatment, and parameters reflecting apoptosis, ROS generation and intracellular calcium elevation were evaluated by using DNA fragmentation, flow cytometry, and western blot analyses. RESULTS SHK 0.5 µM significantly enhanced HT-induced apoptosis as indicated by DNA fragmentation and caspase-3 activation with increased generation of ROS and elevation of intracellular calcium. The combined treatment also synergistically activated proapoptotic proteins and inactivated anti-apoptotic proteins. Furthermore, the phosphorylation of JNK and PKC- δ and the dephosphorylation of ERK and AKT were the upstream effects that may have compounded the induction of apoptosis. The modulatory effects of HT and SHK were abrogated with the employment of NAC and JNK-IN-8 by inactivating the MAPK pathway and cleavage of caspase-3. Intracellular calcium was also elevated and was found to be responsible for the induction of cell death evident by the DNA fragmentation with or without the employment of BAPTA-AM. CONCLUSION Conclusively, this study provides persuasive evidence that SHK in combination with HT is a propitious therapeutic way for augmentation of apoptosis and hence suggest a novel strategy for treating cancers.

Background/Aims: Hyperthermia is a widely used therapeutic tool for cancer therapy and a well-known inducer of apoptosis. Although the flavonoid compound baicalin (BCN) is a potent anticancer agent for several human carcinomas, it is less potent in the human U937 myelomonocytic leukemia cell line. To explore any enhancing effects of BCN on hyperthermia-induced apoptosis, this study investigated the combined effects and apoptotic mechanisms of hyperthermia and BCN in U937 cells. Methods: U937 cells were heat treated at 44ºC for 12 min with or without pre-treatment with BCN (10-50 µM) and then incubated for 6 h at 37 ºC with 5% CO2 and 95% air. Cell viability was analyzed by Trypan blue exclusion assay. Apoptosis was examined by DNA fragmentation, fluorescence microscopy and flow cytometry. Generation of mitochondrial trans-membrane potential (MMP), mitochondrial calcium, and reactive oxygen species (ROS) was also detected by flow cytometry. The expression of proteins related to apoptosis and signaling pathways was determined by western blotting. Results: Hyperthermia alone did not reduce cell viability or induce notable levels of apoptosis, but combined hyperthermia and BCN treatment markedly augmented apoptosis by upregulating proapoptotic proteins and suppressing antiapoptotic proteins, culminating in caspase-3 activation. Mitochondrial transmembrane potential was significantly decreased, and generation of reactive oxygen species (ROS) and suppression of antioxidant enzymes were marked. Furthermore, with the combined treatment, the phosphorylated forms of JNK and p38 showed increased expression, whereas AKT was dephosphorylated. JNK-IN-8 (a JNK inhibitor) and NAC (a ROS scavenger) abrogated the apoptotic effects of the combined treatment, significantly protecting the cells and indicating the involvement of high ROS generation and the MAPK pathway in the underlying molecular mechanism. Conclusion: This study provides compelling evidence that hyperthermia, in combination with BCN, is a promising therapeutic strategy for enhancement of apoptosis and suggest a promising therapeutic approach for cancer.

// Chun-Ting Hu 1, 2 , Li-Li Guo 1, 2 , Na Feng 1, 2 , Lei Zhang 3 , Na Zhou 1 , Li-Li Ma 1 , Lan Shen 1 , Gui-Hui Tong 1 , Qian-Wen Yan 1 , Shi-Jie Zhu 1 , Xiu-Wu Bian 4 , Mao-De Lai 5 , Yong-Jian Deng 1, 2 , Yan-Qing Ding 1, 2 1 Department of Pathology, Nanfang Hospital and School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China 2 Guangdong Provincial Key Laboratory of Molecular Tumor Pathology, Guangzhou 510515, China 3 Department of General Surgery, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200127, China 4 Department of Pathology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China 5 Department of Pathology, School of Medical Sciences, Zhejiang University, Hangzhou 310006, China Correspondence to: Yong-Jian Deng, e-mail: dengyj@smu.edu.cn Yan-Qing Ding, e-mail: dyq@fimmu.com Keywords: colorectal cancer, hepatic sinusoidal endothelial cell, macrophage migration inhibitory factor, chemotaxis, metastasis Received: March 03, 2015 Accepted: May 20, 2015 Published: June 02, 2015 ABSTRACT Growth and invasion of metastatic colorectal cancer (CRC) cells in the liver depend on microenvironment. Here, we showed that human hepatic sinusoidal endothelial cells (HHSECs) induce chemotaxis and outgrowth of CRC cells. Macrophage migration inhibitory factor (MIF), released by HHSECs, stimulated chemotaxis of CRC cells. MIF secreted by HHSECs, but not by CRC cells themselves, promoted migration and epithelial-mesenchymal transition (EMT) and facilitated proliferation and apoptotic resistance of CRC cells. In orthotopic implantation models in nude mice, exogenous MIF stimulated growth of CRC cells and metastasis. Furthermore, MIF accelerated mobility of CRC cells by suppressing F-actin depolymerization and phosphorylating cofilin. Noteworthy, MIF levels were correlated with the size of hepatic metastases. We suggest that HHSECs and paracrine MIF promote initial migration and proliferation of CRC cells in the hepatic sinusoids to generate liver metastases.

Proparacaine is a widely used topical anesthetic in ophthalmic optometry and surgery, and has been reported to have cytotoxic effects on rabbit corneal endothelial cells after prolonged and repeated usage. Since rabbit is an exceptive mammal whose corneal endothelial cells still maintaining proliferation abilities even in adulthood, whether proparacaine has cytotoxic effects on human corneal endothelial (HCE) cells need to be further verified. Our objectives in the present study were to investigate the cytotoxicity to HCE cells of proparacaine and its underlying mechanisms in vitro and verify the cytotoxicity using cat corneal endothelial (CCE) cells in an in vivo model of cat corneas. Cytotoxic evaluation results indicated that a dose- and time-dependent toxic response of HCE cells to proparacaine over 0.03125% was rated based on morphology and viability, and a toxic response of CCE cells to 0.5% (clinical applied dosage) proparacaine was also rated based on cell density and histology. Importantly, treatment with proparacaine resulted in significant elevation of plasma membrane permeability, cell cycle arrest at S phase, fragmentation of genomic DNA, formation of apoptotic bodies, and externalization of phosphatidylserine (PS) of HCE cells. Moreover, proparacaine demonstrated disrupting effects on mitochondrial transmembrane potential (MTP) of HCE cells and activating effects on caspase-3, -8 and -9. This study demonstrates that proparacaine has notable cytotoxicity to both HCE cells in vitro and CCE cells in vivo, and its dose- and time-dependent cytotoxicity to HCE cells is achieved by inducing apoptosis via a mitochondrion-mediated caspase-dependent pathway. These findings provide new insights into the cytotoxicity and apoptosis-inducing effect of local anesthetics which should be used with great caution in the eye clinic.

Objective: To explore the proliferation inhibition and apoptosis-inducing effect of evodiamine in human gastric cancer SGC-7901 cells. Methods: After 48 or 24 h exposure to different concentrations of evodiamine, cell proliferation was analyzed using tetrazolium blue (MTT) assay while apoptosis and cell-cycle phase distribution using flow cytometry. Results: In 0.01～30.00 μg/mL range of concentrations, evodiamine inhibited the proliferation of SGC-7901 cells in dose-dependent manner, and the overall mean IC50 was (3.79±0.16) μg/mL; the apoptosis rate was increased from 3.4% to 7.0%, 13.8% and 36.3% at concentrations of 0, 0.5, 1.5 and 30 μg/mL of evodiamine, respectively; the percentage of cells accumulated in G2/M phase was increased from 17.26% to 98.92% in the cells treated with evodiamine for 24 h in 0.01～30.00 μg/mL range of concentrations. Conclusion: Evodiamine can inhibit the proliferation, induce apoptosis in human gastric cancer cell line SGC-7901 in vitro and arrest the cell cycle at the G2/M phase.

Fenvalerate (Fen), a synthetic pyrethroid insecticide, is widely used in agricultural, domestic and veterinary applications. Fen induces abnormal cell proliferation and apoptosis, which are linked to its hazardous effects. However, this view is controversial and the underlying molecular mechanisms remain elusive. In the present study, the effects of Fen on cadmium (Cd)-induced apoptosis and the associated molecular mechanisms were investigated in human myeloid leukemia U937 cells. U937 cells were treated with 50 μm cadmium chloride (CdCl2 ) with or without Fen pretreatment at 1-50 μm. Apoptosis was evaluated by externalization of phosphatidylserine on the plasma membrane. The expression levels of apoptosis-related proteins, including Bcl-2 family members were determined by western blot analysis. The results revealed that pretreatment with Fen at 20 μm for 12 hours significantly inhibited Cd-induced apoptosis. Decreased expression of pro-apoptotic Bcl-2 family proteins (Noxa and Bid) and increased expression of anti-apoptotic proteins (Bcl-xL, Mcl-1 and XIAP) were observed after combined treatment with Fen and CdCl2 . Phosphorylation of ERK and AKT was increased, while phosphorylation of JNK was decreased by the combined treatment, compared with CdCl2 treatment alone. In conclusion, Fen decreased apoptotic sensitivity induced by Cd in U937 cells. This effect was associated with activation of ERK and AKT, suppression of JNK and changes in expression of Bcl-2 family proteins and XIAP. The present findings suggest a potential influence of Fen on Cd toxicity via suppression of apoptosis. Fen decreased apoptotic sensitivity induced by Cd, and thus it may contribute carcinogenic risk and influence on cancer therapy.

During the past two decades, cytokines have emerged as key molecules to modulate innate and adaptive immunity and mediate anti-tumor activity. Although multiple cytokine types are implicated for such anti-tumor activity in several cancer types, it remains largely unknown in breast cancer. In this study, cytokines that are prior known for antitumor activity in different cancer types were examined against breast cancer using a 4T1 cells based xenograft-model. Our results showed Interleukin-12 (IL-12) (500ng/mouse) significantly suppressed the growth of tumors, while other cytokines showed minimal suppression. Subsequent molecular analysis by flow cytometry and immunohistochemistry confirmed the CD8