Yi Chen

Regulated cell death (RCD), also well-known as programmed cell death (PCD), refers to the form of cell death that can be regulated by a variety of biomacromolecules, which is distinctive from accidental cell death (ACD). Accumulating evidence has revealed that RCD subroutines are the key features of tumorigenesis, which may ultimately lead to the establishment of different potential therapeutic strategies. Hitherto, targeting the subroutines of RCD with pharmacological small-molecule compounds has been emerging as a promising therapeutic avenue, which has rapidly progressed in many types of human cancers. Thus, in this review, we focus on summarizing not only the key apoptotic and autophagy-dependent cell death signaling pathways, but the crucial pathways of other RCD subroutines, including necroptosis, pyroptosis, ferroptosis, parthanatos, entosis, NETosis and lysosome-dependent cell death (LCD) in cancer. Moreover, we further discuss the current situation of several small-molecule compounds targeting the different RCD subroutines to improve cancer treatment, such as single-target, dual or multiple-target small-molecule compounds, drug combinations, and some new emerging therapeutic strategies that would together shed new light on future directions to attack cancer cell vulnerabilities with small-molecule drugs targeting RCD for therapeutic purposes.

Sirtuin 3 (SIRT3) is one of the most prominent deacetylases that can regulate acetylation levels in mitochondria, which are essential for eukaryotic life and inextricably linked to the metabolism of multiple organs. Hitherto, SIRT3 has been substantiated to be involved in almost all aspects of mitochondrial metabolism and homeostasis, protecting mitochondria from a variety of damage. Accumulating evidence has recently documented that SIRT3 is associated with many types of human diseases, including age-related diseases, cancer, heart disease and metabolic diseases, indicating that SIRT3 can be a potential therapeutic target. Here we focus on summarizing the intricate mechanisms of SIRT3 in human diseases, and recent notable advances in the field of small-molecule activators or inhibitors targeting SIRT3 as well as their potential therapeutic applications for future drug discovery.

Abstract Purpose: The survival of patients with hepatocellular carcinoma (HCC) recurrence after curative resection is usually poor. We sought to evaluate the safety and efficacy of adjuvant transarterial chemoembolization (TACE) in HBV-related HCC patients with an intermediate (a single tumor larger than 5 cm without microvascular invasion) or high risk (a single tumor with microvascular invasion, or two or three tumors) of recurrence. Experimental Design: In this randomized phase 3 trial, 280 eligible patients were assigned to adjuvant TACE (n = 140) or no adjuvant treatment (control; n = 140) groups. The primary endpoint was recurrence-free survival (RFS); secondary endpoints included overall survival (OS) and safety. Multivariable Cox-proportional hazards model was used to determine the independent impact of TACE on patients' outcomes. Results: Patients who received adjuvant TACE had a significantly longer RFS than those in the control group [56.0% vs. 42.1%, P = 0.01; HR, 0.68; 95% confidence interval (CI), 0.49–0.93]. Patients in the adjuvant TACE group had 7.8% higher 3-year OS rate than the control group (85.2% vs. 77.4%; P = 0.04; HR, 0.59; 95% CI, 0.36–0.97). The impact of adjuvant TACE on RFS and OS remained significant after controlling for other known prognostic factors (HR, 0.67; P = 0.01 for RFS; and HR, 0.59; P = 0.04 for OS). There was no grade 3 or 4 toxicity after adjuvant TACE. Conclusions: For patients with HBV-related HCC who had an intermediate or high risk of recurrence after curative hepatectomy, our study showed adjuvant TACE significantly reduced tumor recurrence, improved RFS and OS, and the procedure was well tolerated. Clin Cancer Res; 24(9); 2074–81. ©2018 AACR.

The mechanism of Bax/Bak activation remains a central question in mitochondria-dependent apoptotic signaling. While it is established that all proapoptotic Bcl-2 homology 3 (BH3)-only proteins bind and neutralize the anti-apoptotic Bcl-2 family proteins, how this neutralization leads to Bax/Bak activation has been actively debated. Here, genome editing was used to generate cells deficient for all eight proapoptotic BH3-only proteins (OctaKO) and those that lack the entire Bcl-2 family (Bcl-2 allKO). Although the OctaKO cells were resistant to most apoptotic stimuli tested, they underwent Bax/Bak-dependent and p53/Rb-independent apoptosis efficiently when both Bcl-xL and Mcl-1, two anti-apoptotic Bcl-2 proteins, were inactivated or eliminated. Strikingly, when expressed in the Bcl-2 allKO cells, both Bax and Bak spontaneously associated with the outer mitochondrial membrane (OMM) through their respective helix 9, and this association triggered their homo-oligomerization/activation. Together, these results strongly suggest that the OMM, not BH3-only proteins or p53/Rb, is the long-sought-after direct activator of Bax/Bak following BH3-only-mediated neutralization of anti-apoptotic Bcl-2 proteins.

PURPOSE: Advanced metastatic prostate cancer (PCa) is a fatal disease, with only palliative therapeutic options. Though almost 80% of cases of metastatic PCa present bone metastasis, our current understanding of the molecular mechanisms that govern this metastatic dissemination remains fragmentary. The main objective of the present study was to identify microRNA (miRNA) genes that regulate metastatic PCa. EXPERIMENTAL DESIGN: miRNA expression profiling was done in human prostate cell lines to identify dysregulated miRNA components of advanced PCa. miR-203 expression was assessed in prostate carcinoma cell lines and clinical specimens by real-time PCR and in situ hybridization. To assess the biological significance of miR-203, miR-203 was reexpressed in bone metastatic PCa cell lines followed by in vitro and in vivo functional assays. RESULTS: miR-203 expression is specifically attenuated in bone metastatic PCa suggesting a fundamental antimetastatic role for this miRNA. Reintroduction of miR-203 in bone metastatic PCa cell lines suppresses metastasis via inhibition of several critical steps of the metastatic cascade including epithelial-mesenchymal transition, invasion, and motility. Ectopic miR-203 significantly attenuated the development of metastasis in a bone metastatic model of PCa. Importantly, miR-203 regulates a cohort of pro-metastatic genes including ZEB2, Bmi, survivin, and bone-specific effectors including Runx2, a master regulator of bone metastasis. CONCLUSIONS: miR-203 is an "antimetastatic" miRNA in PCa that acts at multiple steps of the PCa metastatic cascade via repression of a cohort of prometastatic targets. miR-203 may be an attractive target for therapeutic intervention in advanced PCa.