JS-K activates G2/M checkpoints through the DNA damage response and induces autophagy via CAMKKß/AMPKα/mTOR pathway in bladder cancer cells.

The aim of this study was to investigate the effects of JS-K, a nitric oxide donor prodrug, on DNA damage and autophagy in bladder cancer (BCa) cells and to explore the potential related mechanisms. Through detecting proliferation viability, cell morphology observation and colony formation assay low concentrations of JS-K significantly inhibited BCa growth while having no effect on normal cells. JS-K induced an increase in the level of DNA damage protein γH2AX and a decrease in the level of DNA damage repair-related proteins PCNA and RAD51 in BCa cells, indicating that JS-K can induce DNA damage in BCa cells and inhibit DNA damage repair. JS-K induced G2/M phase block and calcium overload using flow cytometry analysis. Moreover, we also investigated the levels of cell G2/M cycle checkpoint-related protein and autophagy-associated protein by western blot. The results of our study demonstrated that JS-K induced BCa cells G2/M phase arrest due to upregulating proteins related to DNA damage-related G2/M checkpoint activation (p-ATM, p-ATR, p-Chk1, p-Chk2, and p-Cdc2) and down-regulation of Cyclin B1 protein. In addition, our study demonstrated that JS-K-induced autophagy in BCa cells was related to the CAMKKß/AMPKα/mTOR pathway.

Berberine inhibits the progression of renal cell carcinoma cells by regulating reactive oxygen species generation and inducing DNA damage.

BACKGROUND: Berberine is a natural isoquinoline alkaloid that has been shown to have antitumor properties in a growing number of studies. However, its role in renal cell carcinoma remains unclear. This study investigates berberine's effect and mechanism in renal cell carcinoma. METHODS: The methyl-tetrazolium, colony formation, and lactate dehydrogenase assay were used to detect proliferation and cytotoxicity, respectively. Flow cytometry, caspase-Glo 3/7 assay, and adenosine triphosphate assay were used to detect apoptosis and the adenosine triphosphate levels. Wound healing and transwell assay were used to examine the migration ability of renal cell carcinoma cells. Besides, the level of reactive oxygen species (ROS) was explored using a DCFH-DA-based kit. Additionally, western blot and Immunofluorescence assay was taken to determine the levels of relative proteins. RESULTS: In vitro, our findings indicated that the proliferation and migration of renal cell carcinoma cells treated with berberine in various concentrations were inhibited, while the level of ROS and apoptosis rate were increased. Furthermore, The results of western blot showed that the expression of Bax, Bad, Bak, Cyto c, Clv-Caspase 3, Clv-Caspase 9, E-cadherin, TIMP-1and γH2AX were up-regulated, while Bcl-2, N-cadherin, Vimentin, Snail, Rad51 and PCNA were down-regulated after treating with berberine with various concentration. CONCLUSION: The result of this study revealed that berberine inhibits renal cell carcinoma progression via regulating ROS generation and inducing DNA break.

Erratum: Metformin in combination with JS-K inhibits growth of renal cell carcinoma cells via reactive oxygen species activation and inducing DNA breaks: Erratum.

[This corrects the article DOI: 10.7150/jca.36372.].

[Protective effect of ethyl acetate extract from Bidens bipinnata on hepatocyte damage induced by endoplasmic reticulum stress].

To explore the protective effect and mechanism of ethyl acetate extract from Bidens bipinnata on hepatocyte damage induced by endoplasmic reticulum stress. Tunicamycin was used to establish the damage model in L02 cells. Methyl thiazolyl tetrazolium(MTT) colorimetric assay was used to investigate the survival rate of ethyl acetate extract from B. bipinnata in L02 cells injury induced by endoplasmic reticulum stress; the protein expressions of endoplasmic reticulum stress-related molecule glucose regulated protein 78(GRP78), PKR-like ER kinase(PERK), eukaryotic initiation factor-2(eIF2α), activating transcription factor 4(ATF4), C/EBP homologous protein(CHOP), B-cell CLL/lymphoma 2(Bcl-2), Bal-2 associated X apoptosis regulator(Bax) were examined by Wes-tern blot. The expressions of the above proteins were also detected after endoplasmic reticulum stress inhibitor(4-phenyl butyric acid) and CHOP shRNA-mediated knockdowns were added. The expressions of GRP78, PERK, CHOP in L02 cells were observed by immunofluorescence method. The results showed that ethyl acetate extract from B. bipinnata could significantly increase the survival rate of L02 cell injury caused by endoplasmic reticulum stress in a dose and time-dependent manner(P<0.05 or P<0.01). The expression levels of GRP78, PERK, eIF2α, ATF4, CHOP and Bax in the drug treatment groups were significantly down-regulated(P<0.05 or P<0.01), while Bcl-2 was significantly up-regulated(P<0.01). After endoplasmic reticulum stress inhibitor and CHOP shRNA-mediated knockdowns were added, the expression levels of GRP78, PERK, eIF2α, ATF4, CHOP, Bax in the drug treatment groups were significantly down-regulated(P<0.01), whereas Bcl-2 was significantly up-regulated(P<0.01). Immunofluorescence results showed that the expressions of GRP78, PERK, CHOP were consistent with the Western blot method. In conclusion, ethyl acetate extract from B. bipinnata has a significant protective effect on the damage of L02 cells caused by endoplasmic reticulum stress. The mechanism may be related to the inhibition of endoplasmic reticulum stress and the down-regulation of apoptosis in cells through the PERK/eIF2α/ATF4/CHOP signaling pathway.

[Mn(PaPy2Q)(NO)]ClO4, a Near-Infrared Light activated release of Nitric Oxide drug as a nitric oxide donor for therapy of human prostate cancer cells in vitro and in vivo.

This study was the first to investigate the synthesis of near-infrared light-sensitive NO prodrug [Mn(PaPy2Q)(NO)]ClO4, and detection the amount of NO released by the drug in different time and near infrared light (10 mW, 20 mW). It showed that with the increase of light power, the time required for the drug to release NO was shortened, and we selected 20 mW, 10 min as a follow-up study of light power and irradiation time while ensuring the near-infrared light did not affect tumor cells. The cells were irradiated with 20 mW of near-infrared light for 10 min at 6 h after treatment with the drug on PC-3, LNCaP and 22RV1 cells, and NO concentration and cell survival rate were tested at 12 h, 24 h and 48 h. Experiments showed that NO concentration remained stable within 48 h and [Mn(PaPy2Q)(NO)]ClO4 inhibited the proliferation of cells in a concentration and time-dependent manner. Then we also found that [Mn(PaPy2Q)(NO)]ClO4 increased the expression of apoptosis-related proteins (PARP, Bax, Caspase 3/9), inhibited the expression of BCl-2 and increased the activity level of Caspase 3/7, which showed [Mn(PaPy2Q)(NO)]ClO4 promoted prostate cancer cells apoptosis. Next, the results in xenograft mouse model showed that [Mn(PaPy2Q)(NO)]ClO4 also had anti-prostate cancer effects in vivo, and the NO concentration increased in the tumor after near-infrared light irradiation. After [Mn(PaPy2Q)(NO)]ClO4 treatment 6 weeks, tumor volume was significantly reduced, Ki67 and BrdU protein expression was significantly reduced. TUNEL assay results showed that [Mn(PaPy2Q)(NO)]ClO4 could promote the apoptosis of solid tumors in vivo and in a concentration-dependent manner.

Matrine induces toxicity in mouse liver cells through an ROS-dependent mechanism.

Matrine is major active component in Sophora flavescens Ait that plays pharmacological activities against inflammation, tumors and virus. However, potential toxicity of matrine and its possible toxic mechanisms have not been carefully studied. The aim of the study is to assess the toxicity of matrine on mouse liver cells and to investigate the potential ROS-associated mechanisms. Mice were randomly divided into three groups: vehicle control (normal saline), low-dose (50 mg/kg), and high dose (100 mg/kg) groups. Mice in each group were intraperitoneally injected with matrine daily for 7 d. The livers were collected for analysis of histopathological changes and HO-1 protein expression. Serum was collected for analysis of aspartate aminotransferase and alanine aminotransferase activities. Mouse liver NCTC cells were treated with matrine for certain time, and cell viability, cytotoxicity, apoptosis, expression of proteins, activities of caspase-3 and caspase-9, and levels of ROS generation, mitochondrial membrane potential, and ATP were examined. Increased activities of AST and ALT in serum, and vacuolar degeneration of cytoplasm in liver tissues were observed after treatment. Suppression of cell viability, increase of cytotoxicity, induction of apoptosis, alteration in the expression of apoptotic-related proteins, and activation of caspase-3 and caspase-9 were shown in matrine-treated NCTC cells. Furthermore, matrine induced ROS generation, and suppressed mitochondrial membrane potential and ATP levels, however, the antioxidant N-acetylcysteine reversed matrine-induced hepatotoxicity and ROS generation. These findings suggested that matrine stimulated the generation of ROS, which was possibly involved in matrine-induced toxicity in mouse liver cells in vitro and in vivo.

Circ-APBB1IP as a Prognostic Biomarker Promotes Clear Cell Renal Cell Carcinoma Progression Through The ERK1/2 Signaling Pathway.

Circular RNA (circRNA), a member of non-coding RNA, plays an essential regulatory role in many human physiological and pathological processes; however, its role in clear cell renal cell carcinoma (ccRCC) still unclear. This study aims to investigate the effect and mechanisms of circRNA on ccRCC progression. A human circRNA microarray was used to discover differential expression circRNA, and a quantitative real-time polymerase chain reaction (qRT-PCR) was performed to verify the expression of circRNA. The function and mechanism of circRNA were explored by cell transfection, cell counting kit-8, fluorescein isothiocyanate (FITC) Annexin V apoptosis detection, wound healing, transwell, and western blot. The result indicated that circ-APBB1IP was significantly up-regulated in ccRCC. In vitro, knockdown of circ-APBB1IP by siRNA suppressed the proliferation, migration, and invasion and increased the apoptosis of ccRCC cells. Further study found that knockdown of circ-APBB1IP up-regulated protein expression of cleaved caspase-3, cleaved caspase-7, cleaved caspase-8, cleaved caspase-9, Bax, Bad, Bak, E-cadherin and down-regulated expression of Bcl-2, N-cadherin, MMP-2, MMP-9, p-ERK1/2. Our result indicates that circ-APBB1IP has a vital function in ccRCC tumorigenesis. These findings suggest that circ-APBB1IP represents a novel potential biomarker and therapeutic target of ccRCC.

Metformin in combination with JS-K inhibits growth of renal cell carcinoma cells via reactive oxygen species activation and inducing DNA breaks.

Metformin (MET) is taken as a principal medication for remedying Type 2 diabetes mellitus. Its anti-tumor effect has been reported increasingly, but the precise mechanism of it remains unclear. This study aims to explore the efficacy of MET and MET combined with nitric oxide donor prodrug JS-K on the proliferation, apoptosis, and DNA damage in human renal cell carcinoma (RCC) cells, and investigate the possible molecular mechanism involved. The cell proliferation was tested through methyl-tetrazolium assay and cell apoptosis was ascertained by flow cytometry. The dihydroethidium and JC-1 fluorescent methods were used to detect Reactive oxygen species (ROS) and mitochondrial transmembrane potential (Δψm), respectively. Proteins associated with apoptosis and DNA damage were evaluated by Western blotting. Results showed that MET and JS-K could suppress cell growth, and the inhibition concentration 50 of treatment with MET combined with JS-K (MET + JS-K) showed more toxicity than individual agents on RCC cells. This augmented toxicity was associated with intracellular reactive oxygen species (ROS) level, mitochondrial membrane potential alteration, and induced DNA breaks. The results of Western blotting showed that the expression level of pro-apoptotic proteins, such as Bax, Bak, caspase-3, and caspase-9, was up-regulated, and the anti-apoptotic protein Bcl-2 was down-regulated after treatment using MET alone and MET + JS-K, correspondingly. Moreover, MET + JS-K inhibited the expression of cellular PCNA and Rad51, and immunofluorescence analysis of γH2AX proved that MET + JS-K enhanced DNA damage. In summary, the results of this research indicated that MET and JS-K inhibited RCC cell growth by activating ROS, targeting mitochondria-dependent apoptotic pathways, and inducing DNA breaks.

Pterostilbene Inhibits Human Renal Cell Carcinoma Cells Growth and Induces DNA Damage.

Pterostilbene (PTE) has inhibitory effect on a wide array of tumors. However, the therapeutic potential of PTE in renal cancer cells and the underlying mechanisms have not been evaluated. In this study, the aim is to demonstrate the growth inhibitory and the underlying mechanisms of PTE on human renal cell carcinoma (RCC) cells in vitro. By cell viability, cell morphology and colony formation assays, we found that PTE significantly suppressed the proliferation of RCC cells, while had little toxicity to the normal renal cell line HK-2. Flow cytometry assay revealed that PTE potently induced the apoptosis of RCC cells in a concentration-dependent manner, which was also testified by up-regulation of the pro-apoptosis-related protein (Cyto C, Bad, Bak, Bax, Cleaved-caspase 3, Cleaved-caspase 9, Cleaved-poly(ADP-ribose)polymerase (PARP)) and down-regulation of the anti-apoptosis-related protein Bcl-2. Moreover, cell cycle being arrested in S phase and down-regulation of p-Akt and p-extracellular signal-regulated kinase (ERK)1/2 were observed following treatment with PTE in RCC cells, indicating that PTE exerted remarkable anti-tumor activity in RCC cells possibly via cell cycle arrest and inactivation of Akt and ERK1/2 signaling pathways. Immunofluorescence analysis of γH2AX and detecting the expression levels of γH2AX, proliferating cell nuclear antigen (PCNA) and Rad51 by Western blot showed that PTE induced the DNA damages response in RCC cells. Taken together, the results of the present study demonstrated that PTE was a potential preventive and therapeutic agent for human renal cell carcinoma.

Combination of metformin and paclitaxel suppresses proliferation and induces apoptosis of human prostate cancer cells via oxidative stress and targeting the mitochondria-dependent pathway.

Previous studies have reported that metformin (MET) has anticancer activity. In combination with chemotherapeutic drugs, MET reduces the dosage of chemotherapeutic drugs required and enhances anticancer efficacy. In the present study, the combination of MET and paclitaxel (PTX) in three human prostate cancer (PCa) cell lines (22RV1, PC-3 and LNCaP) was evaluated to investigate the effects on proliferation and apoptosis of PCa cells. The present study explored whether their effects were associated with reactive oxygen species (ROS). An MTT assay and microscopy were used to study the effect of MET + PTX on cell growth. Half maximal inhibitory concentration (IC50) values were obtained for MET (12.281±1.089 mM for 22RV1, 2.248±0.352 mM for PC-3 cells and 3.610±0.577 mM for LNCaP cells) and PTX (13.170±1.12 nM for PC-3 cells) at 48 h. Since the survival rate of 22RV1 and LNCaP cells did not decrease linearly with increasing PTX concentration, it is difficult to estimate accurate IC50; therefore, only IC50 values for PTX in PC-3 cells were given. When treating the cells with 5 mM MET, the IC50 of PTX decreased to 5.423±0.734 nM for PC-3 cells. Annexin V and propidium iodide staining was used to investigate apoptosis by flow cytometry. The apoptotic mechanisms of MET + PTX in PCa were investigated by detecting the expression of apoptosis-related proteins, activities of caspase-3/7, intracellular ROS accumulation, mitochondrial membrane potential, and intracellular levels of adenosine 5'-triphosphate (ATP). MET + PTX induced PCa apoptosis and ROS accumulation, and decreased mitochondrial membrane potential and intracellular levels of ATP. Taken together, these results indicated that MET + PTX suppressed PCa cell proliferation in a dose- and time-dependent manner. In addition, MET + PTX induced apoptosis by increasing ROS levels, reducing mitochondrial membrane potential, and activating mitochondrial-dependent apoptotic pathways.

Resveratrol inhibits proliferation, migration and invasion via Akt and ERK1/2 signaling pathways in renal cell carcinoma cells.

Recent studies have shown that resveratrol (RES) inhibits cancer cell growth, migration and invasion. Here, we evaluated RES in two human renal cell carcinoma (RCC) cell lines, ACHN and A498. We investigated the effects of RES on proliferation, cell morphology, colony formation, migration, and invasion. We used a proliferation assay to demonstrate that RES inhibited cell growth with IC50 values 132.9±1.064µM in ACHN, and 112.8±1.191µM in A498, respectively. Using inverted contrast microscopy, we showed that RES reduced cell-to-cell contact and inhibited formation of filopodia. A wound healing assay showed that RES inhibited migration of RCC cells. A Transwell assay showed that RES inhibited RCC migration and invasion. Western blot analysis showed that RES suppresses expression of N-cadherin, Vimentin, Snail, MMP-2, MMP-9, p-Akt and p-ERK1/2, but increased expression of E-cadherin and TIMP-1. In the presence of PD98059, the inhibitor of ERK1/2 pathway, we repeated all of the above experiments, showed that RES acted via the ERK1/2 pathway. Taken together, our results suggested that RES suppressed RCC cell proliferation, migration, and invasion in a concentration- and time-dependent manner. These effects likely resulted from inactivation of the Akt and ERK1/2 signaling pathways.

Berberine activates caspase-9/cytochrome c-mediated apoptosis to suppress triple-negative breast cancer cells in vitro and in vivo.

Berberine (BBR) is an isoquinoline alkaloid isolated from Cotridis rhizoma and exhibits multiple biological roles including anti-microbe, anti-inflammation and anti-tumor activities. In this study, two triple-negative breast cancer cell (TNBC) lines, MDA-MB-231 and BT549, were used to investigate the effect of BBR on growth of TNBC in vitro and in vivo. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate the viability of cells treated with BBR. After 48h treatments, a 50% inhibitory concentration (IC50) of BBR to BT549 and MDA-MB-231 cells are at 16.575±1.219µg/ml and 18.525±6.139µg/ml respectively. BBR reduced colony formation of BT549 and MDA-MB-231 cells. The wound-healing assay showed BBR decreased breast cancer cell migrations (P<0.01). AnnexinV-PI staining assay confirmed BBR induced cellular apoptosis. The expressions of caspase-3, caspase-9, Bcl-2 and Bax were detected by western blot, which showed BBR activated caspase-3, 9 and Bax, but down-regulated Bcl-2 expression. BBR promoted the release of cytochrome c through the immunofluorescent analysis (P<0.01). We also found BBR increased the level of cellular γH2AX and increased the expression of Ligase4, which suggests BBR induces the double-strand breaks (DSB). These results thus demonstrated that BBR induced DSB, subsequently increased the release of cytochrome c and eventually triggered the caspase9-dependent apoptosis. In addition, we used a MDA-MB-231 mouse-xenograftmodel to evaluate the effect of BBR on tumor growth. BBR suppressed tumor growth and increased caspase-9 levels in xenograft tumors through immunohistochemistry analysis (P<0.01). Taken together, these results demonstrate that BBR activates caspase-9/cytochrome c-mediated apoptosis to inhibit the growth of TNBC breast cancer cells in vitro and in vivo.

Berberine in combination with cisplatin suppresses breast cancer cell growth through induction of DNA breaks and caspase-3-dependent apoptosis.

Berberine (BBR) is an isoquinoline alkaloid extracted from medicinal plants such as Hydrastis canadensis, Berberis aristata and Coptis chinensis. BBR displays a number of beneficial roles in the treatment of various types of cancers, yet the precise mechanisms of its action remain unclear. Cisplatin is an effective cancer chemotherapeutic agent and functions by generating DNA damage, promoting DNA damage-induced cell cycle arrest and apoptosis; however, its efficacy is challenged by the resistance of tumor cells in clinical application. The aim of the present study was to investigate the effects of BBR in combination with cisplatin on human breast cancer cells. MTT assay showed that BBR inhibited breast cancer MCF-7 cell growth with a 50% inhibitory concentration (IC50) value of 52.178±1.593 µM and the IC50 value of cisplatin was 49.541±1.618 µM, while in combination with 26 µM BBR, the IC50 value of cisplatin was 5.759±0.76 µM. BBR sensitized the MCF-7 cells to cisplatin in a time- and dose-dependent manner. After treatment of BBR and cisplatin, the cellular pro-apoptotic capase-3 and cleaved capspase-3 and caspase-9 were upregulated and the anti-apoptotic Bcl-2 was downregulated. Importantly, BBR restrained the expression of cellular PCNA, and immunofluoresence analysis of γH2AX showed that BBR increased the DNA damages induced by cisplatin. Taken together, the results demonstrated that BBR sensitized MCF-7 cells to cisplatin through induction of DNA breaks and caspase-3-dependent apoptosis.

Inhibition effects of scorpion venom extracts (Buthus matensii Karsch) on the growth of human breast cancer MCF-7 cells.

BACKGROUND: To observe the inhibition effects of the Buthus matensii Karsch (BmK) scorpion venom extracts on the growth of human breast cancer MCF-7 cells, and to explore its mechanisms. METHODS: Two common tumor cells (SMMC7721, MCF-7) were examined for the one which wasmore sensitivity to scorpion venom by MTT method. Cell cycle was determined by flow cytometry. Immunocytochemistry was applied to detect apoptosis-related protein Caspase-3 and Bcl-2 levels, while the expression of cell cycle-related protein Cyclin D1 was shown by Western blotting. RESULTS: Our data indicated that MCF-7 was the more sensitive cell line to scorpion venom. The extracts of scorpion venom could inhibit the growth and proliferation of MCF-7 cells. Furthermore, the extract of scorpion venom induced apoptosis through Caspase-3 up-regulation while Bcl-2 down-regulation in MCF-7 cells. In addition, the extracts of scorpion venom blocked the cells from G0/G1 phase to S phase and decreased cell cycle-related protein Cyclin D1 level after drug intervention compared with the negative control group. CONCLUSIONS: These results showed that the BmK scorpion venom extracts could inhibit the growth of MCF-7 cells by inducing apoptosis and blocking cell cycle in G0/G1 phase. The BmK scorpion venom extracts will be very valuable for the treatment of breast cancer.

[Relationship between organochlorine pollution in soil and rice and the incidence of colorectal cancer in Jiashan county, Zhejiang province].

OBJECTIVE: To study the relationship between organochlorine and colorectal cancer. METHODS: With multistage cluster random sampling, 11 towns were drawn based on the standardized incidence of colorectal cancer. Administrative and natural villages were drawn subsequently. Rice and soil samples in the paddy fields were collected in the villages. The contents of organochlorine were detected. Rank correlation analysis was performed together with the data of colorectal cancer incidence. RESULTS: The contents of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in both rice and soil samples were below the amounts of the country. Statistics showed that the standardized incidence rates were significantly different among the 11 towns. The contents of delta-HCH, gamma-HCH, sodium pentachlorophenate in rice and those of delta-HCH in soil were statistically different among the towns through the rank sum test. The standardized incidence of colorectal cancer was significantly connected with the content of total DDT in rice while rectal cancer with total DDT and PP'-DDE and colon cancer with 1245 of polychlorinated biphenyl (PCBs). The correlation coefficients were 0.636, 0.691, 0.716 and 0.658 respectively (P < 0.05). CONCLUSIONS: Rectal cancer was statistically correlated with organochlorine, mainly for total DDT and dichlorodiphenyldichloroethylene (PP'-DDE). Colon cancer was significantly associated with 1245 of PCBs. Further study should be performed since this research was only an ecological study.

Meta analysis of risk factors for colorectal cancer.

AIM: To study the risk factors for colorectal cancer in China. METHODS: A meta-analysis of the risk factors of colorectal cancer was conducted for 14 case-control studies, and reviewed 14 reports within 13 years which included 5034 cases and 5205 controls. Dersimonian and Laird random effective models were used to process the results. RESULTS: Meta analysis of the 14 studies demonstrated that proper physical activities and dietary fibers were protective factors (pooled OR<0.8), while fecal mucohemorrhage, chronic diarrhea and polyposis were highly associated with colorectal cancer (all pooled OR>4). The stratified results showed that different OR values of some factors were due to geographic factors or different resources. CONCLUSION: Risks of colorectal cancer are significantly associated with the histories of intestinal diseases or relative symptoms, high lipid diet, emotional trauma and family history of cancers. The suitable physical activities and dietary fibers are protective factors.