Immune Checkpoint Inhibitors-Related Thyroid Dysfunction: Epidemiology, Clinical Presentation, Possible Pathogenesis, and Management

Immune checkpoint inhibitors (ICIs) are a group of drugs employed in the treatment of various types of malignant tumors and improve the therapeutic effect. ICIs blocks negative co-stimulatory molecules, such as programmed cell death gene-1 (PD-1) and its ligand (PD-L1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), reactivating the recognition and killing effect of the immune system on tumors. However, the reactivation of the immune system can also lead to the death of normal organs, tissues, and cells, eventually leading to immune-related adverse events (IRAEs). IRAEs involve various organs and tissues and also cause thyroid dysfunction. This article reviews the epidemiology, clinical manifestations, possible pathogenesis, and management of ICIs-related thyroid dysfunction.

Protective Effect of Mitochondrially Targeted Peptide Against Oxidant Injury of Cone Photoreceptors Through Preventing Necroptosis Pathway

Retinopathy is an eye disease caused by the death of retinal cells in the macular area and the surrounding choroid. As the retinal rod cell dysfunction and death lead to the loss of night vision, the disease will lead to visual dysfunction and blindness as the disease progresses. Because of the irreversible nature of cell death, gene therapy has become a research hotspot in the field of retinopathy. But the technology is still in animal studies or clinical trials, and more research is needed to prove its feasibility. In this study, oxidative damage cell model was established and divided into a control group, H2O2 group, SS31 +NEC1 group, SS31 +H2O2 group, and SS31 +NEC1 +H2O2 group, for different interventions. The cell survival rate of the H2O2 group was significantly increased compared with those of the SS31 + H2O2 group, SS31 +NEC1 +H2O2 group, and NEC1 +H2O2 group. Nec1 combined treatment significantly reduced reactive oxygen species (ROS) production compared with that in the H2O2 group. The level of MDA in the SS31 group, Nec-1 group and combined treatment of SS31 +NEC1 group decreased significantly compared with the H2O2 group. The proportion of cells with decreased mitochondrial membrane potential in the H2O2 group significantly increased, and the rate of positivity for propidium iodide (PI) of 661W cells in the H2O2 group and the control group significantly increased. Nine hours after H2O2 treatment of 661W cells, the RIP3 expression level began to increase, and peaked at 24 h. The level of RIP3 in the H2O2 group was significantly increased, while this level was downregulated in the SS31 and NEC1 treatment groups. Therefore, this study suggests that SS31 has a partial protective effect on 661W cells by inhibiting necrosis, which has certain guiding significance for the treatment of retinal diseases.

Synthesis of Silica Based Nanoparticles against the Proliferation of Human Prostate Cancer

Background: Prostate cancer(PCa) has the second-highest morbidity and mortality rates in men. Possessing facile surface chemistry and unique optical properties make silica nanoparticles(SiO2-NPs) promising cancer therapy materials. Objective: This study aimed to investigate the effects of SiO2-NPs and their derivatives, including SiNP-NH2, SiNP-Cl, and SiNP-SH against PCa and clarify their molecular mechanism on cell death, gene, and protein expressions. Methods: Following the synthesis and derivation of SiO2-NPs, their characterization was carried out using TEM, DLS, BET, and FT-IR. Cytotoxic properties of the compounds were investigated against different human cancerous cells, including HUH-7, A549, DLD-1, HeLa, NCI-H295R, and PC-3, as well as human healthy epithelium cell line PNT1A. Results: SiNP-NH2, SiNP-Cl, and SiNP-SH dose-dependently inhibited the proliferation of PC-3 cells with an IC50 value as 55.46 µg/mL, 55.09 µg/mL and 72.89 µg/mL, respectively.SiNP-SH significantly(p<0.0001) inhibited metastasis and invasion of PC-3 cells(20.4% and 46.7%, respectively), and significantly(p<0.0001) increased early apoptosis(32.3%) when compared with non-treated cells. Protein and mRNA expressions of BcL-2, Bax, caspase-3, caspase-9, caspase-12, p53, Smad-4, Kras, and Nf-ĸB were also altered following the treatment of SiO2-NPs and its derivatives. Conclusion: Our results demonstrated that –SH functioned SiO2-NPs can prevent the proliferation of human PCa by increasing apoptosis by upregulating gene and protein expression of p53(TP53) as well as caspase-3, caspase-9, and caspase-12 in the apoptotic pathway. Besides, the increased level of Smad-4 has also implicated the decreased cell proliferation. Hence, low sized SiNP-SH nanoparticles might be a suitable candidate for the treatment of human PCa.

Bevacizumab treatment nullifies Bax up-regulation induced by epirubicin and docetaxel chemotherapy in human breast cancer.

Chemotherapeutics utilized in breast cancer, including taxane drugs such as docetaxel, exert their function through a variety of mechanisms; one of these is the induction of apoptotic genes (1) like those of the Bcl-2 family (2). We found through mining published data from the Phase II PROMIX trial (3) that treatment with epirubicin and docetaxel chemotherapy resulted in the induction of the Bcl-2 family gene Bax (4) which functions in the execution of cell death. However, following addition of bevacizumab to the treatment regimen, Bax expression returned to levels even lower than at baseline. This was not the case in glioblastoma patients treated with bevacizumab, demonstrating tissue-specific function of bevacizumab in human cancer (5). Thus, in patients with breast cancer, bevacizumab antagonizes activation of cell death gene expression induced by epirubicin and docetaxel chemotherapy, demonstrating an undesirable effect of a therapeutic utilized for the treatment of cancer - a disease, a major feature of which is the acquired ability to evade death signaling (6).

Drosophila p53 directs nonapoptotic programs in postmitotic tissue

TP53 is the most frequently mutated gene in human cancers, and despite intensive research efforts, genome-scale studies of p53 function in whole animal models are rare. The need for such in vivo studies is underscored by recent challenges to established paradigms, indicating that unappreciated p53 functions contribute to cancer prevention. Here we leveraged the Drosophila system to interrogate p53 function in a postmitotic context. In the developing embryo, p53 robustly activates important apoptotic genes in response to radiation-induced DNA damage. We recently showed that a p53 enhancer (p53RErpr) near the cell death gene reaper forms chromatin contacts and enables p53 target activation across long genomic distances. Interestingly, we found that this canonical p53 apoptotic program fails to activate in adult heads. Moreover, this failure to exhibit apoptotic responses was not associated with altered chromatin contacts. Instead, we determined that p53 does not occupy the p53RErpr enhancer in this postmitotic tissue as it does in embryos. Through comparative RNA-seq and chromatin immunoprecipitation–seq studies of developing and postmitotic tissues, we further determined that p53 regulates distinct transcriptional programs in adult heads, including DNA repair, metabolism, and proteolysis genes. Strikingly, in the postmitotic context, p53-binding landscapes were poorly correlated with nearby transcriptional effects, raising the possibility that p53 enhancers could be generally acting through long distances.

The Antioxidative Action of ZTP by Increasing Nrf2/ARE Signal Pathway

So far, more than 25,000 brain diseases have been shown to be related to oxidative stress. Excessive free radicals and reactive oxygen species (ROS) can attack cells resulting in dysfunctional proteins, lipids, and nucleic acid, finally leading to imbalance of energy metabolism, cell death, gene mutation, and immune reaction. Therefore oxidative stress plays an important role in neuronal diseases. As a traditional Chinese medicine, Zhengtian Pill (ZTP) was reported to have the ability to reduce the blood viscosity of migraine model rats, with increased beta-endorphin, serotonin, adrenaline, and dopamine in brain tissue. Moreover ZTP can effectively accelerate blood circulation and attenuate blood coagulation. However, the molecular mechanisms of ZPT are still unclear. Through the behavioral test we found that ZTP can significantly improve depression-like behavior induced by LPS when rat was treated with ZTP (L 0.17 g/kg, M 0.34 g/kg, and H 0.7 g/kg) intraperitoneal injection once a day for 30 consecutive days. And ZTP can resist oxidative stress (>72 h) for a longer time. And ZTP can promote the levels of ATP and SOD and reduce the levels of ROS and MDA in the brain. At the same time, ZTP can have antioxidant stress through increasing the expression level of Nrf2/HO-1/P38. These results show that ZTP may be a potential antioxidant stress drug for variety of diseases associated with oxidative stress injury.

A Cut/cohesin axis alters the chromatin landscape to facilitate neuroblast death

Precise control of cell death in the nervous system is essential for development. Spatial and temporal factors activate the death of Drosophila neural stem cells (neuroblasts) by controlling the transcription of multiple cell death genes through a shared enhancer, enh1. The activity of enh1 is controlled by abdominalA and Notch, but additional inputs are needed for proper specificity. Here we show that the Cut DNA binding protein is required for neuroblast death, acting downstream of enh1. In the nervous system, Cut promotes an open chromatin conformation in the cell death gene locus, allowing cell death gene expression in response to abdominalA. We demonstrate a temporal increase in global H3K27me3 levels in neuroblasts, which is enhanced by cut knockdown. Furthermore, cut regulates the expression of the cohesin subunit Stromalin in the nervous system. The cohesin components Stromalin and NippedB are required for neuroblast death, and knockdown of Stromalin increases repressive histone modifications in neuroblasts. Thus Cut and cohesin regulate apoptosis in the developing nervous system by altering the chromatin landscape.Summary statementCut regulates the programmed death of neural stem cells by altering cohesin levels and promoting a more open chromatin conformation to allow cell death gene expression.