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Background: In recent years, anti-angiogenic peptides have received considerable attention as candidates for cancer treatment. Arresten is an angiogenesis inhibitor that cleaves from the α1 chain of type IV collagen and stimulates apoptosis in endothelial cells. We have recently indicated that a peptide corresponding to the amino acid 78 to 86 of arresten, so-called Ars, prevented the migration and tube formation of HUVECs and the colon carcinoma growth in mice significantly. The current study aimed to determine whether induction of apoptotic cell death in endothelial cells is one of the biochemical mechanisms of this anti-angiogenic peptide. Methods and results: This hypothesis was assessed using the MTT assay, cell cycle analysis, Annexin V-FITC/PI staining, BCL2, CASP8, CASP9, p53, and CDKN2A gene expression studies as well as evaluating apoptosis in tumor tissues by TUNEL assay. Results demonstrated that 40 µM of Ars significantly stimulated 46.2% of early and late apoptosis in HUVECs compared to 13.6% in the untreated cells and did not significantly alter the cell cycle distribution. Moreover, BCL2 and CASP8 were down-regulated, while CASP9 and p53 were up-regulated in endothelial cells. CDKN2A gene expression, the regulator of G1 cell cycle arrest, was not significantly altered. Conclusions: It might be suggested that Ars induced apoptosis in endothelial cells through the mitochondrial pathway and had no effect on the cell cycle. Besides, Ars induced apoptosis significantly in vivo. However, further studies are required to confirm the detailed molecular mechanism of Ars, this peptide has the potential to be optimized for clinical translations. [ABSTRACT FROM AUTHOR]

Abstract Caffeic acid phenethyl ester (CAPE) is a bioactive component of honeybee propolis, which has protective effect against heavy metal induced toxicology. Cadmium is a kind of heavy metal pollutant that is hazardous to human health especially liver, and apoptosis is an important mechanism related to cadmium injury. Circular RNAs (CircRNAs) are involved in the regulation of apoptosis. However, the protective effects of CAPE on cadmium‐induced cell apoptosis through CircRNA related mechanisms remains unclear at the current stage. In the present research, cell‐based studies revealed that treating HepG2 cells with CdCl2 (0–30 μM; 24 h) caused a dose‐dependent decrease in cell viability, and CAPE at 10 μM could reverse such a decrease. The circular RNA hsa‐circ‐0010039 may function as a ceRNA for the microRNA miR‐661 to enhance caspase 9 expression and regulate apoptosis. The anti‐apoptotic effects of CAPE against CdCl2‐induced injury may be achieved through inhibiting the expression of hsa‐circ‐0010039 and caspase 9 while up‐regulating miR‐661 expression. This is the first report on the involvement of circRNA in CAPE's alleviating effect on CdCl2‐induced injury and apoptosis. The hsa_circ_0010039/miR‐661/caspase9 axis deserves further research efforts especially in search of dietary interventions for cadmium injury.

Despite profound advancement in the field of cancer treatment, the disease is still one of the deadliest in the world. In this aspect, nanotechnology is emerging as a highly promising area to be focussed upon. In this study, we investigated the cytotoxic effect of synthesized chitosan-functionalized gold nanoparticles (G1) having a diameter of 15–20 nm on hormone-responsive MCF7 and hormone therapy-resistant MDA-MB-231 breast cancer cell lines. We found significant mortality of these two cancer cell types with the IC50 as low as ~ 11 ppb just after 48 h of treatment without exhibiting any cytotoxic effect on normal human peripheral blood lymphocytes. In both cancer cell lines, G1 induced severe cytomorphological alterations and reactive oxygen species overload with subsequent activation and nuclear translocation of master stress-regulator Nrf2 as an antioxidant response. Consequently, nuclear fragmentation and subsequent apoptotic cell death were evident that progressed primarily through activation of the Bax–Caspase9–Caspase3–PARP1 axis being concomitant with p53–p21 mediated cell cycle arrest. Moreover, disturbed homeostasis of cellular elements like copper, chlorine, potassium, sulfur, selenium and calcium further strengthened our findings. Therefore, G1 can be concluded as highly effective against two major types of breast cancer cells without any significant toxic effect in normal cells which might popularize it as a potent candidate for breast cancer therapeutics warranting further research. [ABSTRACT FROM AUTHOR]

Optogenetics enables the spatio-temporally precise control of cell and animal behavior. Many optogenetic tools are driven by light-controlled protein–protein interactions (PPIs) that are repurposed from natural light-sensitive domains (LSDs). Applying light-controlled PPIs to new target proteins is challenging because it is difficult to predict which of the many available LSDs, if any, will yield robust light regulation. As a consequence, fusion protein libraries need to be prepared and tested, but methods and platforms to facilitate this process are currently not available. Here, we developed a genetic engineering strategy and vector library for the rapid generation of light-controlled PPIs. The strategy permits fusing a target protein to multiple LSDs efficiently and in two orientations. The public and expandable library contains 29 vectors with blue, green or red light-responsive LSDs, many of which have been previously applied ex vivo and in vivo. We demonstrate the versatility of the approach and the necessity for sampling LSDs by generating light-activated caspase-9 (casp9) enzymes. Collectively, this work provides a new resource for optical regulation of a broad range of target proteins in cell and developmental biology. Unlabelled Image • Optogenetic tools permit the spatio-temporal control of protein and cell function. • A new method efficiently prepares modular optogenetic tools. • The method combines a genetic engineering strategy and photoreceptor library. • Using the strategy and library, light-activated caspases were developed. • Optical regulation of diverse target proteins is now more directly accessible. [ABSTRACT FROM AUTHOR]

Structural and biological studies were conducted on the novel complexes [Fe(U) 2 (H 2 O) 2 ]Cl 3 (FeU) and [Ru(U) 2 (H 2 O) 2 ]Cl 3 (RuU) (U = 5,6-Diamino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione) to develop an anticancer drug candidate. The two complexes have been synthesized and characterized. Based on our findings, these complexes have octahedral geometry. The DNA-binding study proved that both complexes coordinated with CT-DNA. The docking study confirmed the potency of both complexes in downregulating the topoisomerase I protein through their high binding affinity. Biological studies have established that both complexes can act as potent anticancer agents against three cancer cell lines. RuU or FeU complexes induce apoptosis in breast cancer cells by increasing caspase9 protein and inhibiting proliferating cell nuclear antigen (PCNA) activity. In addition, both complexes down-regulate topoisomerase I expression in breast cancer cells. Therefore, the RuU and FeU complexes' anticancer activities were mediated via both apoptosis induction and topoisomerase I down-regulation. In conclusion, both complexes have dual anticancer activity pathways that may be responsible for the selective cytotoxicity of the complexes. This makes them more suitable for the development of novel cancer treatment strategies. FeU and RuU complexes decrease topoisomerase I expression and induce apoptosis via proliferating cell nuclear antigen (PCNA) and caspase 9 regulation. [Display omitted] • Novel Ru(III) and iron(III) complexes containing uracil were synthesized as anticancer drug candidates. • Docking's study confirmed that both complexes block the topoisomerase I (TOPO I) protein. • In vitro study proves that both complexes were potent against three cancer cell lines. • RuU or FeU complexes induce apoptosis in breast cancer cells (MCF-7), as well as down-regulating TOPO I. • FeU lower cost and higher availability could make it a more attractive option for researchers and clinicians. [ABSTRACT FROM AUTHOR]

• The current study describes synthesis and characterization of hexa-coordinated quercetin - based RhIII complex. • The structural characterization was achieved by several physicochemical measurements and showed an octahedral stereochemistry. • The final structure of [RhIIIL 2 ClH 2 O] was confirmed using PXRD–structural analysis by processing the XRD data of microcrystalline powder by the computer program Expo 2014. • The synthesized rhodium(III) complex showed moderate SOD-like activity and good ability for DNA binding in addition to it exhibited a promising anti-proliferative activity with minimal toxicity to normal cells compared with cis-platin. Quercetin – based rhodium(III) complex, [RhIIIL 2 ClH 2 O], L is quercetin, was synthesized via the direct interaction between the polyphenolic natural product (3,3′,4′,5,7-pentahydroxylflavone) and RhCl 3 3H 2 O. Characterization of the pure isolated metal complex by analytical, electrolytic conductance, TGA and spectroscopic techniques demonstrated the stoichiometric ratio 1:2 metal to ligand. The final structure of [RhIIIL 2 ClH 2 O] was confirmed using PXRD–structural analysis by processing the XRD data of microcrystalline powder by the relevant computer program Expo 2014. The mimetic catalytic activity of superoxide dismutase (SOD) was studied and the obtained results showed that [RhIIIL 2 ClH 2 O] has mid activity compared to other SOD mimics. By analogy with the work of the original-SOD and its functional models, a mechanism for SOD-mimicking catalytic activity of the newly synthesized rhodium(III) complex has been proposed. The binding of the Rh(III) chelate to DNA was tested, and spectroscopic investigations indicated the successful binding of the metal complex to DNA by the groove/electrostatic binding pattern with intrinsic binding constants K b of 2.76 × 106 M−1. In addition, the quercetin – based RhIII exhibits relatively higher DPPH scavenger power than the free quercetin. The in vitro data indicated the efficient anti-proliferative activities of the current rhodium(III) complex compared with cis-platin with increased safety on normal cells. In addition, our data revealed that the studied RhIII complex could prevent cancer cell replication with increasing the p53 levels, inhibit both Bcl2 and MMP9, then activating caspase 9, which then cleaves caspase 3, leading to apoptosis triggering. Apoptosis activation led to cell cycle arrest at the pre-G1 phase and decreased Hela cell proliferation, which appeared in the decreased G2/M phase. Ongoing biological assays indicate that the current Rh(III) complex is a promising anti-proliferative agent with minimal toxicity to normal cells. [ABSTRACT FROM AUTHOR]

Abnormal apoptosis is one of the hallmarks of cancers including acute myeloid leukemia (AML), as it plays a pivotal role in precisely maintaining self-renewal, proliferation, and differentiation properties of hematopoietic stem cells (HSCs). Caspase9 (CASP9), an initiator caspase activated by mitochondrial-mediated apoptotic pathway (intrinsic pathway), triggers cascade of effector caspases and executes apoptosis. Functional SNPs in CASP9 might influence the gene expression leading to altered apoptosis which confer the risk to AML. To test this hypothesis, we have analyzed four CASP9 gene polymorphisms [CASP9 − 1263A > G (rs4645978), CASP9 − 712C > T (rs4645981), CASP9 − 293_275del CGTGAGGTC AGTGCGGGGA (−293del) (rs4645982), and CASP9 Ex5 + 32G > A (rs1052576)] in 180 AML cases and 304 age- and sex-matched healthy controls. We performed various statistical analyses to determine the potential interactions between these SNPs and AML. The study revealed that presence of G allele at CASP9 − 1263 position elevates the risk of AML 1.53-fold and CT/TT genotype at CASP9 − 712 position by 2.60-fold under dominant model of inheritance. Two CASP9 haplotypes, G-del-C-A and G-del-T-A, were found to be significantly associated with increased AML risk by 2.19- (95 % confidence interval (CI), 1.09-4.39; p = 0.028) and 11.75-fold (95 % CI, 1.01-136.57; p = 0.05), respectively. Further, multidimensionality reduction (MDR) analysis had revealed single locus CASP9 − 712C > T SNP and four loci CASP9 − 1263A > G, CASP9 − 293del, CASP9 − 712C > T, and CASP9 Ex5 + 32G > A SNPs as highest predicting models for AML development. Our results revealed a significant association of two SNPs in CASP9 (−1263A > G and −712C > T) and two haplotypes of the four SNP combinations with AML susceptibility. [ABSTRACT FROM AUTHOR]

Liver cancer is one of the most common cancers in the world and the second leading cause of death in cancer patients. There is an urgent need for an effective and less toxic treatment for liver cancer. Saponins of Marsdenia Tenacissima (SMT) as a potential anticancer drug has attracted extensive attention of researchers because of its effective biological activity. The effect of SMT on HepG2 Li-7 and L-02 cells was detected by CCK8 assay. At the same time, the apoptosis rate was detected by flow cytometer and laser confocal microscope, and the morphological changes of mitochondria were observed under electron microscope. The levels of bax, cytochrome c, caspase-9, caspase-3, cleaved caspase-3 and protein were detected using Western bolt. Finally, BALB/c was subcutaneously injected with H22 cells to form tumors, and SMT was intragastrically injected to detect the size of the transplanted tumor. SMT can induce apoptosis in vitro and reduce the size of transplanted tumor in vivo . Increases the rate of apoptosis through the cytochrome c pathway and regulates the expression of apoptosis-related proteins. These results suggest that SMT may be one of the potential candidates for the treatment of liver cancer., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Abstract: Overexpression of anti-apoptotic Bcl2 family proteins is often seen in cancers rendering them insensitive to apoptosis inducing anticancer strategies. Anti-apoptotic Bcl2 family proteins are associated with different organelles like mitochondria and endoplasmic reticulum (ER) and exert their anti-apoptotic activity by inhibiting the release of Cyt.C from mitochondria irrespective of its localization. Here, we have identified a long term survival function for Bcl2 targeted at ER in mammalian system compared to wild type Bcl2 that is mediated by enhanced phosphorylation of heat shock protein 27 at ser 15, 78 and 82 sites with inhibition of caspase9 activity. Phosphorylation of hsp27 was prevented and the survival of ER-Bcl2 cells was reversed by inhibiting p38 and MEK suggesting that these kinases can act as the upstream targets for hsp27 phosphorylation. The results suggest that Bcl2 possess additional survival function in the regulation of apoptosis which is primarily regulated by its association with the ER in an hsp27 dependent manner. The interplay of both hsp27 and ER-Bcl2 in providing long term survival to cancer cells is interesting since both of these proteins are overexpressed in tumors with aggressive phenotype. The results suggest that spatial localization of Bcl2 family proteins also play a key role in long term survival of cancers indicating another level of functional regulation of Bcl2 in cancer cell survival. [Copyright &y& Elsevier]

The CDK inhibitor, p21, exhibits an antiapoptotic or proapoptotic effect, in addition to its anti-proliferative effect, depending on the conditions. To define the apoptosis-regulatory function of p21, we constructed cells that stably express C-terminal deletion mutants of p21 (full length 164aa), 1–157, 1–147 or 1–128, and evaluated the apoptotic response of these cells. The AnnexinV positive cell fraction after γ-irradiation did not increase in cells expressing 1–157. Consistently, an increase of caspase3 activity or the active form of caspase3 was not observed in cells expressing 1–157, but was prominent in cells expressing 1–128 and 1–147. Further, the activity of caspase9 was suppressed in γ-irradiated cells expressing 1–157. The antiapoptotic effect of 1–157 was weaker in Fas-induced apoptosis. Our data indicate that the 1–157 region of p21 inhibits apoptosis caused by γ-irradiation by reducing the activity of caspase9 and caspase3, and the 148–157 region is critical for its inhibiting activity. [Copyright &y& Elsevier]

Myocardial ischemia/hypoxia-reperfusion injury mediates the progression of multiple cardiovascular diseases. It has been reported that knockdown of adaptor protein containing a PH domain, PTB domain and leucine zipper motif 1 (APPL1) is a significant factor for the progression of myocardial injury. However, the role of APPL1 in myocardial ischemia remains unclear. Hence, the aim of the present study was to investigate the specific mechanism underlying the role of APPL1 in myocardial ischemia.In our study, the mRNA level of APPL1 was detected by quantitative real-time PCR (RT-qPCR). The expressions of APPL1, Apoptotic protease activating factor-1 (APAF-1), cleaved caspase9 and other inflammation- and apoptosis-related proteins were determined by western blotting. The secretion of inflammatory cytokines and lactate dehydrogenase (LDH) levels were measured by commercial assay kits. The H9C2 cell viability was analyzed by cell counting kit-8 (CCK-8) assay. The apoptosis rate of H9C2 cells was analyzed by TUNEL assay. The interaction between APPL1 and APAF-1/caspase9 was determined by Immunoprecipitation (IP).Our findings demonstrated that APPL1 was low expressed in myocardial ischemia tissues and cells. APPL1 knockdown suppressed the viability of myocardial ischemia cells and aggravated hypoxia/reperfusion-induced LDH hypersecretion, inflammation and apoptosis. In addition, the overexpression of APPL1 induced inactivation of APAF-1/Caspase9 signaling pathway. Significantly, APAF1 inhibitor reversed the effect of APPL1 knockdown on viability, LDH secretion, inflammation and apoptosis.We conclude that APPL1 inhibits myocardial ischemia/hypoxia-reperfusion injury via inactivation of APAF-1/Caspase9 signaling pathway. Hence, APPL1 may be a novel and effective target for the treatment of myocardial ischemia.

Objective: To investigate the effects of hedyotis diffusa (injection) on mitochondrial membrane potential and expressions of apoptosis-related genes in human gastric cancer cell line MNK-45 cells. Methods: The human gastric cancer MNK-45 cells were divided into 4 groups, each group was set with 3 replicates. The control group was MNK-45 cells without added hedyotis diffusa; the 3 groups of experimental groups were treated with hedyotis diffusa at final concentrations of 20 , 30, 40 μg / ml respectively; each group was incubated for 48 h in a 5% carbon dioxide incubator, and the morphological changes of the cells were observed under a laser confocal microscope. Mitochondrial membrane potential was detected by flow cytometry. The expressions of Cytochrome C ( Cyt c ), caspase3 and caspase9 genes and proteins were detected by qRT-PCR and Western blot respectively. Results: Compared with the control group, the mitochondrial membrane potentials of MNK-45 cells were significantly reduced in the hedyotis diffusa treated groups at final concentrations of 20, 30, and 40 μg / ml ( P ＜0. 01). The gene expressions of Cyt c , caspase3 , and caspase9 were significantly up-regulated ( P ＜0. 01) and their protein expressions were also significantly increased ( P ＜0. 05 or P ＜0. 01). The 40 μg / ml hedyotis diffusa treatment group performed best. Conclusion: In the final concentration range of 20 ~ 40 μg / ml, hedyotis diffusa can reduce human gastric cancer MNK-45 cells mitochondrial membrane potential, induce apoptosis and up-regulate Cyt c, caspase3 and caspase9 gene expressions.

Given the prevalence and annual incidence of cancer, head and neck cancer is affecting more than 600,000 people each year. In this research, it was decided to investigate that which genes are involved and how MPO, NQO1, SOD2 enzyme levels effective to develop of head and neck cancer and for the first time at the tissue level. 35 tumor tissues in all head and neck anatomy and their surrounding tissue (70 in total) were enclosed the research that received surgery. Determination of the apoptosis genes expression levels (Mtch1, Akt1, Caspase3, Caspase9, Bcl2, Mdm2, mTOR) were determined by RT-PCR techniques and the same patients' sample used for ROS associated oxidant-antioxidant system by using MPO, NQO1, SOD2 enzyme levels using ELISA method. According to statistical results, caspase 9 gene was found statistically high expressed in early stage in contrast to late stage (p=0,013). Level of SOD2, NQO1 and MPO was determined and only MPO level was found significantly important on tumor tissues p=0,008).  Specially, our findings for high expression of Cas9 on early stage were thought to be the target for treatment with its well-known initiator role of the apoptosis. Our results suggest that the higher level of MPO in tumor tissues and indicates that it has some role on pathology of head and neck cancers. We believe that, our research will lead the proposal in-vivo studies and will open new areas on therapeutic targets.