Influenza A virus infection activates caspase-8 to enhance innate antiviral immunity by cleaving CYLD and blocking TAK1 and RIG-I deubiquitination.

Caspase-8, an aspartate-specific cysteine protease that primarily functions as an initiator caspase to induce apoptosis, can downregulate innate immunity in part by cleaving RIPK1 and IRF3. However, patients with caspase-8 mutations or deficiency develop immunodeficiency and are prone to viral infections. The molecular mechanism underlying this controversy remains unknown. Whether caspase-8 enhances or suppresses antiviral responses against influenza A virus (IAV) infection remains to be determined. Here, we report that caspase-8 is readily activated in A549 and NL20 cells infected with the H5N1, H5N6, and H1N1 subtypes of IAV. Surprisingly, caspase-8 deficiency and two caspase-8 inhibitors, Z-VAD and Z-IETD, do not enhance but rather downregulate antiviral innate immunity, as evidenced by decreased TBK1, IRF3, IκBα, and p65 phosphorylation, decreased IL-6, IFN-ß, MX1, and ISG15 gene expression; and decreased IFN-ß production but increased virus replication. Mechanistically, caspase-8 cleaves and inactivates CYLD, a tumor suppressor that functions as a deubiquitinase. Caspase-8 inhibition suppresses CYLD cleavage, RIG-I and TAK1 ubiquitination, and innate immune signaling. In contrast, CYLD deficiency enhances IAV-induced RIG-I and TAK1 ubiquitination and innate antiviral immunity. Neither caspase-3 deficiency nor treatment with its inhibitor Z-DEVD affects CYLD cleavage or antiviral innate immunity. Our study provides evidence that caspase-8 activation in two human airway epithelial cell lines does not silence but rather enhances innate immunity by inactivating CYLD.

Stellate ganglion block alleviates postoperative sleep disturbance in patients undergoing radical surgery for gastrointestinal malignancies.

STUDY OBJECTIVES: We explored the effects of stellate ganglion block on postoperative sleep disturbance in patients scheduled to undergo radical surgery for gastrointestinal malignancies. METHODS: Forty such patients were randomly assigned to the control group (Group C) or the preoperative stellate ganglion block treatment group (Group S). Using actigraphy, sleep quality was evaluated on the first night before the operation and first, second, and third postoperative nights. The Pittsburgh Sleep Quality Index scale was used for sleep state assessment on 1 day preoperatively and the first, second, third, fifth, and seventh days postoperatively. Plasma interleukin (IL)-1, IL-6, and IL-10 and melatonin levels were checked at 1 day preoperatively and the first and third days postoperatively. Mean arterial pressure, heart rate, and pulse oxygen saturation (SpO2) were recorded before general anesthesia induction, immediately after tracheal intubation, at the beginning of the operation, 1 and 2 hours after the beginning of the operation, at the end of the operation, immediately after extubation, and 30 minutes after transfer to the postanesthesia care unit. RESULTS: Compared with Group C, in Group S sleep efficiency, total sleep time, and sleep maintenance were increased and sleep period change index, number of awakenings, wake after sleep onset, and body movements were reduced on the first and second postoperative nights; Pittsburgh Sleep Quality Index scores and occurrence of postoperative sleep disturbance were lower on the first and second nights postoperatively; IL-6 was reduced on the first night postoperatively; IL-1 and IL-10 were reduced on the third night postoperatively; melatonin was increased on the first night postoperatively; and mean arterial pressure and heart rate were decreased before general anesthesia induction, immediately after tracheal intubation, and at the end of the operation (all P < .05). Conclusions: Stellate ganglion block alleviates postoperative sleep disturbance by reducing postoperative inflammatory response, increasing melatonin levels, and stabilizing perioperative hemodynamics in patients undergoing radical surgery for gastrointestinal malignancies. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: The Effect of Stellate Ganglion Block on Postoperative Sleep Disturbance and Cognitive Function in Elderly Surgical Patients; URL: https://clinicaltrials.gov/ct2/show/NCT04800653; Identifier: NCT04800653. CITATION: Yan S, Wang Y, Yu L, et al. Stellate ganglion block alleviates postoperative sleep disturbance in patients undergoing radical surgery for gastrointestinal malignancies. J Clin Sleep Med. 2023;19(9):1633-1642.

Interleukin-17A mRNA Expression is Associated with the Prognosis of Patients with Colorectal Cancer: A Pooled Meta-Analysis.

BACKGROUND: Interleukin-17A is a proinflammatory cytokine that is produced by TH17 cells, and plays a dual role in tumor progression, infectious diseases, and autoimmune disorders. Interleukin-17A is induced during colorectal tumorigenesis and angiogenesis, although some studies have reported an anti-tumor effect as well. The aim of our study was to assess the prognostic role of interleukin-17A in colorectal cancer and determine the potential mechanisms. METHODS: The GEO database was searched using the keyword "colorectal cancer", and 10 datasets were identified that included interleukin-17A mRNA expression and survival data of several colorectal cancer patient cohorts. The patients were stratified into the interleukin-17Ahigh and interleukin-17Alow groups based on the median expression level. RESULTS: Higher interleukin-17A mRNA levels were associated with better overall survival rates and the early tumor stage, indicating a protective role of interleukin-17A in colorectal cancer. Furthermore, interleukin-17A mRNA expression also correlated positively with that of TNFS11, CCR6, and CCL20, indicating that the anti-tumor effect of interleukin-17A is likely mediated by enhancing tumor antigen presentation by dendritic cells and recruiting the activated tumor-specific CD8+ cytotoxic T lymphocytes. The IL-23 and STAT3 mRNA levels were also significantly higher in the interleukin-17Ahigh group, which points to an upstream regulatory role of IL-23/STAT3 axis. Finally, the immune checkpoints PDCD1 (PD-1) and CD274 (PDL-1) were also positively correlated with interleukin-17A mRNA expression, indicating that interleukin-17A is a promising predictor of the immunotherapeutic outcome of PD-1/PDL-1 blockade in colorectal cancer. CONCLUSION: Interleukin-17A mRNA is a protective factor in colorectal cancer and a promising biomarker for assessing the prognosis and immunotherapeutic response.

TOX3 regulates the proliferation and apoptosis of colorectal cancer by downregulating RhoB via the activation of the MAPK pathway.

TOX high mobility group box family member 3 (TOX3) can function as tumor suppressor or oncogene in different tumors, while ras homolog family member B (RhoB) is a well-known tumor suppressor. The expression and role of TOX3 in colorectal cancer (CRC) are unknown. This study aimed to investigate the expression of TOX3 in CRC and the role of TOX3/mitogen-activated protein kinase (MAPK)/RhoB signaling in the proliferation and apoptosis of CRC cells. We showed that TOX3 messenger RNA (mRNA) and protein expression levels were significantly upregulated in CRC tissues and cell lines. High TOX3 expression was associated with high T stage, nodal invasion, and advanced tumor stage. Disease-free survival (DFS) was shortened for CRC patients with high expression of TOX3, while overall survival showed no significant difference. TOX3 promoted proliferation, inhibited apoptosis, and decreased the sensitivity to oxaliplatin of CRC cells. In addition, the inhibition of TOX3 led to the upregulation of RhoB, and RhoB overexpression suppressed the proliferation and promoted apoptosis of CRC cells. Moreover, TOX3 overexpression upregulated MAPK signaling, while MAPK signaling inhibitor U0126 induced CRC cell proliferation arrest or apoptosis, and attenuated the inhibition of RhoB in TOX3 overexpression cells. In addition, the overexpression of TOX3 increased tumor volume in nude mice. In conclusion, TOX3 may be an oncogene in CRC and can predict DFS in CRC patients. TOX3/MAPK/RhoB signaling plays an important role in the modulation of proliferation and apoptosis of CRC cells.

Long Non-Coding RNA Duxap8 Facilitates Cell Proliferation and Induces Apoptosis in Colorectal Cancer via miR-519b/ZNF277 Axis.

INTRODUCTION: Long non-coding RNAs (LncRNAs) play a critical role in development and progression of various cancers. More and more researchers pay attention to the effect of lncRNA on regulating the cancer. However, the function and mechanism of Duxap8 in colorectal cancer have not been studied. METHODS: Reverse transcription quantitative PCR (RT-qPCR), cell counting kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU), colony formation assay, flow cytometry, TdT-mediated dUTP nick-end labeling (TUNEL), Western blot, hematoxylin-eosin staining (HE), in situ hybridization (ISH) analysis, immunohistochemistry (IHC) and tumor transplantation experiment were performed to investigate the function and mechanism of Duxap8 in colorectal cancer. RESULTS: We found that the expression level of Duxap8 in colorectal cancer was closely correlated with tumor size (P = 0.024), tumor depth (P = 0.035) and lymphatic invasion (P =0.067) among 50 colorectal cancer patients. Then, we proved that the expression level of Duxap8 was significantly increased in human colorectal cancer tissues and cell lines. Functionally, Duxap8 knockdown inhibited the proliferation and induced the apoptosis of colorectal cancer cells, while Duxap8 overexpression facilitated the proliferation and suppressed the apoptosis in colorectal cancer in vitro. Moreover, knockdown of Duxap8 inhibited the size and weight of tumors in mice injected with colorectal cancer cells, overexpression of Duxap8 promoted the growth of colorectal cancer cells in vivo. Mechanically, we found that Duxap8 was principally located in the cytoplasm. Furthermore, Duxap8 functioned as a competing endogenous RNA to induce the development and progression of colorectal cancer through sponging miR-519b-3p to upregulate ZNF277. DISCUSSION: Taken together, our results demonstrated that Duxap8 enhanced the expression level of ZEB1 to promote via competing for miR-519b-3p, which might be a promising molecular therapeutic target of colorectal cancer.