Anti-apoptotic BCL-2 family members in development

Expression of pro-apoptotic markers is increased along the osteochondral junction in naturally occurring osteochondrosis

Osteochondrosis (OC) is a naturally occurring disease of the articular-epiphyseal cartilage and subchondral bone layers, leading to pain and decreased mobility. The objective of this study was to characterize gene and protein expression of apoptotic markers in chondrocytes surrounding cartilage canals and along the osteochondral junction of osteochondrosis (OC)-affected and normal cartilage, using naturally occurring disease in horses. Paraffin-embedded osteochondral samples (6 OC, 8 normal controls) and cDNA from chondrocytes captured with laser capture microdissection (4 OC, 6 normal controls) were obtained from the lateral trochlear ridge of femoropatellar joints in 14 immature horses (1–6 months of age). Equine-specific caspase-3, caspase-8, caspase-10, Fas, Bcl-2, BAG-1, TNFα, cytochrome C, thymosin-β10, and 18S mRNA expression levels were evaluated by two-step real-time quantitative PCR. Percentage of cell death was determined using the TUNEL method. Protein expression of caspase-10, Fas, cytochrome C, and thymosin-β10 was determined following immunohistochemistry. Statistical analysis was performed using the Wilcoxon rank sum test or two-sample t-test (p < 0.05). In OC samples, there was significantly increased gene expression of caspase-10, Fas, cytochrome C, and thymosin-β10 in chondrocytes along the osteochondral junction and increased Fas gene expression in chondrocytes adjacent to cartilage canals, compared to controls. In OC samples, higher matrix Fas and cytochrome C protein expression, lower mitochondrial cytochrome C protein expression, and a trend for higher cytoplasmic caspase-10 protein expression were found. Collectively, these results suggest that both extrinsic and intrinsic apoptotic pathways are activated in OC cartilage. Increased apoptosis of osteochondral junction chondrocytes may play a role in OC, based on increased gene expression of several pro-apoptotic markers in this location.

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Pro-apoptotic marker gene expression increased in osteochondrosis cartilage

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Extrinsic and intrinsic apoptotic pathways activated along osteochondral junction

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Higher caspase-10, Fas, cytochrome C, and thymosin-β10 gene expression

Platinated graphene oxide: A nanoplatform for efficient gene-chemo combination cancer therapy

Cisplatin (CisPt) is one of the most effective antitumor drugs against a wide range of solid cancers, and recent studies have indicated that combination of CisPt and RNA interference (RNAi) agents would effectively enhance therapeutic index, while the development of simple yet robust dual-delivery systems still remains a challenge. Here, we demonstrated that platinated graphene oxide is an excellent platform to achieve such goal. Nano-Graphene oxide (NGO) was easily platinated by CisPt, and the resulting CisPt/NGO was characterized by several aspects. As a proof-of-concept, an antisense microRNA-21 (Anti-miR-21) was employed as a potential RNAi agent. While most previous work functionalized NGO with cationic polymers for gene delivery, we demonstrated that platinated NGO is a potent carrier to load Anti-miR-21 with improved capacity and adsorption stability. With Anti-miR-21 loading, the system displayed significantly enhanced cytotoxicity to cancer cells, suggesting a synergistic effect. Finally, the underlying mechanism of the improved efficacy was explored, which can be ascribed to the cell apoptosis induced by Anti-miR-21 for gene silencing. This work demonstrated platinated graphene oxide as an effective nanocarrier to co-deliver CisPt and gene therapy for the treatment of cancer.

Shengmai injection reduces apoptosis and enhances angiogenesis after myocardial ischaemia and reperfusion injury in rats

OBJECTIVES

To investigate whether Shengmai injection (SMI) helps to improve cardiac function and enhances angiogenesis after myocardial ischaemia reperfusion injury (MIRI). A rat model of MIRI was created via occlusion of the left anterior descending coronary artery for 30 min, followed by 3 days or 7 days of reperfusion (n = 6 each group).

BACKGROUNDS

SMI is widely used for the treatment of myocardial infarction. The mechanism underlying the effect on cardiac function is not known and whether SMI has any effects on angiogenesis during treatment of MIRI is not clear.

RESULTS AND CONCLUSION

Echocardiography showed that SMI improved the left ventricular ejection fraction (LVEF) in the rat model of MIRI. TUNEL staining indicated that SMI decreased the myocardial apoptosis rate after MIRI. This result may be related to the increase of Bcl-2 expression in the SMI group and a reduction in Bax and caspase 3 expression, as determined by immunohistochemical staining. Small vessels (<60 μm in diameter) of the heart of rats in the group treated with SMI were denser (more numerous) than those in the heart of rats in the other groups. Real-time PCR indicated that the SMI-driven reduction in apoptosis was associated with a change in the ratio of Bcl-2 to Bax expression, and treatment-induced angiogenesis was associated with enhanced vascular endothelial growth factor A (VEGF) expression. We elucidated that SMI promotes angiogenesis, which is important for the development of cardiac remodelling after MIRI.

Reversal Effects of Bound Polyphenol from Foxtail Millet Bran on Multidrug Resistance in Human HCT-8/Fu Colorectal Cancer Cell

Foxtail millet is the second-most widely planted species of millet and the most important cereal food in China. Our previous study showed that bound polyphenol of inner shell (BPIS) from foxtail millet bran displayed effective antitumor activities in vitro and in vivo. The present research further implied that BPIS has the ability to reverse the multidrug resistance of colorectal cancer in human HCT-8/Fu cells, the IC₅₀ values of 5-fluorouracil (5-Fu), oxaliplatin (L-OHP), and vincristine (VCR) were decreased form 6593 ± 53.8, 799 ± 48.9, and 247 ± 10.3 μM to 5350 ± 22.3 (3261 ± 56.9), 416 ± 16.6 (252 ± 15.6), and 144 ± 8.30 (83.8 ± 5.60) μM when HCT-8/Fu cells were pretreated with 0.5 (1.0) mg/mL BPIS for 12 h. The 12 phenolic acid compounds of BPIS were identified by ultraperformance liquid chromatography-triple-time of flight/mass spectrometry (UPLC-Triple-TOF/MS) method. Especially, the fraction of molecular weight (MW) < 200 of BPIS reversed the multidrug resistance in HCT-8/Fu cells, and ferulic acid and p-coumaric acid were the main active components, the IC₅₀ values were 1.23 ± 0.195 and 2.68 ± 0.163 mg/mL, respectively. The present data implied that BPIS significantly enhanced the sensitivity of chemotherapeutic drugs through inhibiting cell proliferation, promoting cell apoptosis, and increasing the accumulation of rhodamine-123 (Rh-123) in HCT-8/Fu cells. Real-time polymerase chain reaction (RT-PCR) and Western blot data indicated that BPIS also decreased the expression levels of multidrug resistance protein 1 (MRP1), P-glycoprotein (P-gp), and breast cancer resistance protein (BCRP). Collectively, these results show that BPIS has potential ability to be used as a new drug-resistance reversal agent in colorectal cancer.

Post-Transcriptional Regulation of Anti-Apoptotic BCL2 Family Members

Anti-apoptotic B cell lymphoma 2 (BCL2) family members (BCL2, MCL1, BCLxL, BCLW, and BFL1) are key players in the regulation of intrinsic apoptosis. Dysregulation of these proteins not only impairs normal development, but also contributes to tumor progression and resistance to various anti-cancer therapies. Therefore, cells maintain strict control over the expression of anti-apoptotic BCL2 family members using multiple mechanisms. Over the past two decades, the importance of post-transcriptional regulation of mRNA in controlling gene expression and its impact on normal homeostasis and disease have begun to be appreciated. In this review, we discuss the RNA binding proteins (RBPs) and microRNAs (miRNAs) that mediate post-transcriptional regulation of the anti-apoptotic BCL2 family members. We describe their roles and impact on alternative splicing, mRNA turnover, and mRNA subcellular localization. We also point out the importance of future studies in characterizing the crosstalk between RBPs and miRNAs in regulating anti-apoptotic BCL2 family member expression and ultimately apoptosis.

The BCL-2 arbiters of apoptosis and their growing role as cancer targets

Impaired apoptosis plays a central role in cancer development and limits the efficacy of conventional cytotoxic therapies. Deepening understanding of how opposing factions of the BCL-2 protein family switch on apoptosis and of their structures has driven development of a new class of cancer drugs that targets various pro-survival members by mimicking their natural inhibitors, the BH3-only proteins. These ‘BH3 mimetic’ drugs seem destined to become powerful new weapons in the arsenal against cancer. Successful clinical trials of venetoclax/ABT-199, a specific inhibitor of BCL-2, have led to its approval for a refractory form of chronic lymphocytic leukaemia and to scores of on-going trials for other malignancies. Furthermore, encouraging preclinical studies of BH3 mimetics that target other BCL-2 pro-survival members, particularly MCL-1, offer promise for cancers resistant to venetoclax. This review sketches the impact of the BCL-2 family on cancer development and therapy, describes how interactions of family members trigger apoptosis and discusses the potential of BH3 mimetic drugs to advance cancer therapy.