Epithelial STAT6 O-GlcNAcylation drives a concerted anti-helminth alarmin response dependent on tuft cell hyperplasia and Gasdermin C.

The epithelium is an integral component of mucosal barrier and host immunity. Following helminth infection, the intestinal epithelial cells secrete "alarmin" cytokines, such as interleukin-25 (IL-25) and IL-33, to initiate the type 2 immune responses for helminth expulsion and tolerance. However, it is unknown how helminth infection and the resulting cytokine milieu drive epithelial remodeling and orchestrate alarmin secretion. Here, we report that epithelial O-linked N-Acetylglucosamine (O-GlcNAc) protein modification was induced upon helminth infections. By modifying and activating the transcription factor STAT6, O-GlcNAc transferase promoted the transcription of lineage-defining Pou2f3 in tuft cell differentiation and IL-25 production. Meanwhile, STAT6 O-GlcNAcylation activated the expression of Gsdmc family genes. The membrane pore formed by GSDMC facilitated the unconventional secretion of IL-33. GSDMC-mediated IL-33 secretion was indispensable for effective anti-helminth immunity and contributed to induced intestinal inflammation. Protein O-GlcNAcylation can be harnessed for future treatment of type 2 inflammation-associated human diseases.

To die or not to die: Gasdermins in intestinal health and disease.

Intestinal homeostasis is achieved by the balance among intestinal epithelium, immune cells, and gut microbiota. Gasdermins (GSDMs), a family of membrane pore forming proteins, can trigger rapid inflammatory cell death in the gut, mainly pyroptosis and NETosis. Importantly, there is increasing literature on the non-cell lytic roles of GSDMs in intestinal homeostasis and disease. While GSDMA is low and PJVK is not expressed in the gut, high GSDMB and GSDMC expression is found almost restrictively in intestinal epithelial cells. Conversely, GSDMD and GSDME show more ubiquitous expression among various cell types in the gut. The N-terminal region of GSDMs can be liberated for pore formation by an array of proteases in response to pathogen- and danger-associated signals, but it is not fully understood what cell type-specific mechanisms activate intestinal GSDMs. The host relies on GSDMs for pathogen defense, tissue tolerance, and cancerous cell death; however, pro-inflammatory milieu caused by pyroptosis and excessive cytokine release may favor the development and progression of inflammatory bowel disease and cancer. Therefore, a thorough understanding of spatiotemporal mechanisms that control gasdermin expression, activation, and function is essential for the development of future therapeutics for intestinal disorders.

Senp7 deficiency impairs lipid droplets maturation in white adipose tissues via Plin4 deSUMOylation.

Lipid metabolism is important for the maintenance of physiological homeostasis. Several members of the small ubiquitin-like modifier (SUMO)-specific protease (SENP) family have been reported as the regulators of lipid homeostasis. However, the function of Senp7 in lipid metabolism remains unclear. In this study, we generated both conventional and adipocyte-specific Senp7 KO mice to characterize the role of Senp7 in lipid metabolism homeostasis. Both Senp7-deficient mice displayed reduced white adipose tissue mass and decreased size of adipocytes. By analyzing the lipid droplet morphology, we demonstrated that the lipid droplet size was significantly smaller in Senp7-deficient adipocytes. Mechanistically, Senp7 could deSUMOylate the perilipin family protein Plin4 to promote the lipid droplet localization of Plin4. Our results reveal an important role of Senp7 in the maturation of lipid droplets via Plin4 deSUMOylation.

Blocking Caspase-1/Gsdmd and Caspase-3/-8/Gsdme pyroptotic pathways rescues silicosis in mice.

Millions of patients suffer from silicosis, but it remains an uncurable disease due to its unclear pathogenic mechanisms. Though the Nlrp3 inflammasome is involved in silicosis pathogenesis, inhibition of its classic downstream factors, Caspase-1 and Gsdmd, fails to block pyroptosis and cytokine release. To clarify the molecular mechanism of silicosis pathogenesis for new therapy, we examined samples from silicosis patients and genetic mouse models. We discovered an alternative pyroptotic pathway which requires cleavage of Gsdme by Caspases-3/8 in addition to Caspase-1/Gsdmd. Consistently, Gsdmd-/-Gsdme-/- mice showed markedly attenuated silicosis pathology, and Gsdmd-/-Gsdme-/- macrophages were resistant to silica-induced pyroptosis. Furthermore, we found that in addition to Caspase 1, Caspase-8 cleaved IL-1ß in silicosis, explaining why Caspase-1-/- mice also suffered from silicosis. Finally, we found that inhibitors of Caspase-1, -3, -8 or an FDA approved drug, dimethyl fumarate, could dramatically alleviate silicosis pathology through blocking cleavage of Gsdmd and Gsdme. This study highlights that Caspase-1/Gsdmd and Caspase-3/8/Gsdme-dependent pyroptosis is essential for the development of silicosis, implicating new potential targets and drug for silicosis treatment.

Medial sural artery perforator free flap versus radial forearm free flap in oral cavity reconstruction and donor site morbidity.

OBJECTIVE: Radial Forearm Free flap (RFFF) is widely used in head and neck reconstruction, yet its donor site defect remains a significant drawback. The Medial Sural Artery Perforator Free Flap (MSAPFF) is considered an alternative flap to RFFF. This study aims to comprehensively analyze their characteristics, outcomes, and their impact on patient quality of life. METHODS: All patients who underwent oral cavity reconstruction using RFFF and MSAPFF between February 2017 and April 2023 were included in this study. Flap characteristics, outcomes and post-operative complications were recorded and compared. Subjective donor site morbidity, aesthetic and functional results, and quality of life were also analyzed. RESULTS: The study included 76 patients: 37 underwent reconstruction with RFFF, and 39 with MSAPFF. There was no significance difference between the RFFF and MSAPFF regarding the success rate (97.2% vs 97.4%), flap size (4.8 × 8.8 cm2 vs 5 × 9.8 cm2), hospital of stay (15.5 days vs 13.5 days) and recipient site complications (P > 0.05). However, MSAPFF showed larger flap thickness (P = 0.001), smaller arterial caliber (P = 0.008), shorter pedicle length (P = 0.001), and longer harvesting time (P < 0.001). No significant difference was observed between the pre-and postoperative ranges of wrist and ankle movements or in recipient site complications. MSAPFF showed a significant difference in donor site morbidity (P < 0.05). CONCLUSION: The MSAPFF is an excellent alternative to the RFFF for repairing oral cavity defects, with additional advantage of a well-hidden scar on the posterior calf, a larger flap thickness, accepted pedicle length and arterial caliber. However, one should consider the harvesting time and surgical skills required in comparison to the RFFF. CLINICAL RELEVANCE: The study highlights the importance of the MSAPFF as an alternative option for RFFF with less donor site morbidity and high success rate in oral cavity reconstruction and improved patient Quality of life after ablative surgery.

Modified submandibular mandibulotomy approach versus lip-splitting approach in tongue cancer surgery: a retrospective paired-cohort study.

OBJECTIVES: The surgical approach for resection and reconstruction of tongue cancer (TSCC) with or without the lip-splitting incision is controversial. This study introduced a modified approach without lip-splitting and the clinical results were assessed. METHODS: Sixty-eight TSCC patients underwent surgery using the modified submandibular mandibulotomy (MSMM) approach without lip-splitting, and another matched 68 patients using lip-splitting mandibulotomy (LSM) approach were enrolled in this study. The clinical results including intraoperative relevance and surgical morbidities, survival status, facial appearance and scar scores, function of lower lip, and quality of life (QOL) were evaluated. RESULTS: The primary tumors were en bloc resected through the MSMM approach with excellent tumor exposure and R0 resection margins as LSM approach. The survival status and complications were similar in both groups. The function of lower lip was better in patients of MSMM group at 1 month after surgery. The MSMM approach was associated with significantly better facial appearance and recreation compared to LSM approach by scar scores and QOL assessment. CONCLUSION: The MSMM approach without lip-splitting achieves similar tumor control, better aesthetic results, and QOL compared to LSM approach. It is a safe and effective surgical approach for patients with TSCC. CLINICAL RELEVANCE: The MSMM approach without lip-splitting is oncological safety in tongue cancer surgery and is scrutinized as one part of the treatment concept for better aesthetic results.

Nitrosonisoldipine is a selective inhibitor of inflammatory caspases and protects against pyroptosis and related septic shock.

Pyroptosis is a type of acute cell death that mainly occurs in immune cells. It is characterized with robust release of inflammatory cytokines and has emerged to play a critical role in the pathogenesis of sepsis-associated immune disorders. In this study, we screened for pyroptotic inhibitors with the ultimate goal to benefit sepsis treatments. Accidentally, we identified that nitrosonisoldipine (NTS), a photodegradation product of calcium channel inhibitor nisoldipine, inhibits noncanonical pyroptosis. Using murine immortalized BM-derived macrophage and human THP-1 cell line, we further discovered that NTS not only inhibits noncanonical pyroptosis mediated by caspase-11 or caspase-4 but also canonical pyroptosis mediated by caspase-1. Mechanistically, NTS directly inhibits the enzyme activities of these inflammatory caspases, and these inhibitory effects persist despite extensive washout of the drug. By contrast, apoptosis mediated by caspase-3/-7 was not affected by NTS. Mice pretreated with NTS intraperitoneally displayed improved survival rate and extended survival time in LPS- and polymicrobe-induced septic models, respectively. In conclusion, NTS is a selective inhibitor of inflammatory caspases that blocks both the noncanonical and canonical pyroptotic pathways. It is safe for intraperitoneal administration and might be used as a prototype to develop drugs for sepsis treatments.

Circ-OMAC drives metastasis in oral squamous cell carcinoma.

OBJECTIVES: Accumulating studies have proved that the circular RNAs (circRNAs) play vital roles in human cancers. However, few circRNAs have been elucidated with lymph node metastasis. This study demonstrated that circ-oral cancer metastasis-associated circRNA (circ-OMAC) is required to regulate the oral squamous cell carcinoma (OSCC) metastasis. MATERIALS AND METHODS: The circ-OMAC were detected by circRNA-sequencing and further verified by in situ hybridization (ISH). The role of circ-OMAC was assessed by transwell assay and wound healing assay. Mechanistically, circ-OMAC regulated OSCC metastasis by initiating the epithelial-to-mesenchymal transition (EMT) signaling pathway. RESULTS: Our findings suggested that circ-OMAC was aberrantly elevated in the metastatic lymph nodes as compared to primary OSCC tissues. OSCC patients with high levels of circ-OMAC were prone to a poor prognosis. By developing functional assays, we confirmed that circ-OMAC promotes metastasis of OSCC cells via initiation of EMT pathways. CONCLUSIONS: We provide new insights whereby Circ-OMAC as an oncogene is a potential therapeutic target and prognostic marker in oral cancer.

The Deficiency of SCARB2/LIMP-2 Impairs Metabolism via Disrupted mTORC1-Dependent Mitochondrial OXPHOS.

Deficiency in scavenger receptor class B, member 2 (SCARB2) is related to both Gaucher disease (GD) and Parkinson's disease (PD), which are both neurodegenerative-related diseases without cure. Although both diseases lead to weight loss, which affects the quality of life and the progress of diseases, the underlying molecular mechanism is still unclear. In this study, we found that Scarb2-/- mice showed significantly reduced lipid storage in white fat tissues (WAT) compared to WT mice on a regular chow diet. However, the phenotype is independent of heat production, activity, food intake or energy absorption. Furthermore, adipocyte differentiation and cholesterol homeostasis were unaffected. We found that the impaired lipid accumulation of Adiponectin-cre; Scarb2fl/fl mice was due to the imbalance between glycolysis and oxidative phosphorylation (OXPHOS). Mechanistically, the mechanistic target of rapamycin complex 1 (mTORC1)/ eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1) pathway was down-regulated in Scarb2 deficient adipocytes, leading to impaired mitochondrial respiration and enhanced glycolysis. Altogether, we reveal the role of SCARB2 in metabolism regulation besides the nervous system, which provides a theoretical basis for weight loss treatment of patients with neurodegenerative diseases.

Hypertonic saccharide solution delays pyroptosis in murine macrophages regardless of the membrane binding of gasdermin D N-terminal.

Pyroptosis is a type of programmed lytic cell death that could be activated by either the canonical or noncanonical inflammasome pathway. In this study, we aimed to examine the effect of hypertonic solution on noncanonical pyroptosis in macrophage. We found that although hypertonic solution had a general inhibitory effect on noncanonical pyroptosis, the underlying mechanism varied by the solute causing hypertonicity. Specifically, hypertonic NaCl or KCl solution inhibited the cleavage of gasdermin D, the pore-forming protein in pyroptosis, whereas hypertonic saccharide solution did not affect the cleavage or membrane binding of gasdermin D. In this case, nevertheless, pyroptosis was still inhibited as evidenced by the preserved mitochondria activity and cell membrane permeability.

Comparison of postoperative cytokine and hormone between endoscopically assisted and open parotid tumor resection.

OBJECTIVE: Endoscopically assisted extracapsular dissection through a single incision along the cephaloauricular furrow has been adapted as a method of access for operating on benign parotid gland tumors. However, no study has compared the immune and stress responses after surgery between the endoscopic procedure and conventional open surgery. METHODS: Through a randomized method, 50 patients with benign parotid gland tumors were assigned to undergo either endoscopically assisted extracapsular dissection or open parotidectomy. The postoperative inflammatory changes and hormonal response in the patients were analyzed at serum level during the preoperative period and at 12, 24, and 72 hr after either surgery. RESULTS: Twenty-three patients received an endoscopic procedure, while 27 underwent open surgery. The size of the incision, amount of intraoperative bleeding, volume of drainage, postoperative pain score, and satisfaction with appearance were all improved in the endoscopic procedure group. Additionally, the serum levels of C-reactive protein, interleukin (IL)-6, IL-10, and cortisol were significantly lower in the endoscopy group in comparison with those in the open surgery group. CONCLUSION: Endoscopically assisted extracapsular dissection on patients with benign parotid gland tumors is associated with lower inflammatory changes and hormone responses than open surgery, thereby reducing perioperative pathophysiological disturbance and enhancing recovery after surgery.

Super-enhancer-associated MEIS1 promotes transcriptional dysregulation in Ewing sarcoma in co-operation with EWS-FLI1.

As the second most common malignant bone tumor in children and adolescents, Ewing sarcoma is initiated and exacerbated by a chimeric oncoprotein, most commonly, EWS-FLI1. In this study, we apply epigenomic analysis to characterize the transcription dysregulation in this cancer, focusing on the investigation of super-enhancer and its associated transcriptional regulatory mechanisms. We demonstrate that super-enhancer-associated transcripts are significantly enriched in EWS-FLI1 target genes, contribute to the aberrant transcriptional network of the disease, and mediate the exceptional sensitivity of Ewing sarcoma to transcriptional inhibition. Through integrative analysis, we identify MEIS1 as a super-enhancer-driven oncogene, which co-operates with EWS-FLI1 in transcriptional regulation, and plays a key pro-survival role in Ewing sarcoma. Moreover, APCDD1, another super-enhancer-associated gene, acting as a downstream target of both MEIS1 and EWS-FLI1, is also characterized as a novel tumor-promoting factor in this malignancy. These data delineate super-enhancer-mediated transcriptional deregulation in Ewing sarcoma, and uncover numerous candidate oncogenes which can be exploited for further understanding of the molecular pathogenesis for this disease.

Epidermis-Activated Gasdermin-A3 Enhances Thermogenesis of Brown Adipose Tissue through IL-6/Stat3 Signaling.

Missense mutations in the gasdermin-A3 (Gsdma3) gene are associated with skin inflammation and hair loss in mice. However, the physiological function of Gsdma3 remains unclear. Herein, we reported that mice carrying the Gsdma3 Y344H mutation that encodes a presumptive activated form of Gsdma3 show increased heat production along with lower body fat percentages. Detailed analysis indicated that this metabolic phenotype is mediated by serum IL-6-induced up-regulation of thermogenesis in brown adipose tissue. The mutant form of Gsdma3 promotes the expression of IL-6 in the epidermis in a c-Jun N-terminal kinase (JNK) signaling-dependent manner. The higher whole-body heat production in alopecia and excoriation mice could be suppressed by an IL-6 receptor/GP130 inhibitor. Our results uncovered Gsdma3/IL-6-dependent cross talk between the skin and brown adipose tissue.

Full cheek defect reconstruction using ALTF versus RFF: Comparison of quality of life, clinical results, and donor site morbidity.

OBJECTIVES: This study aimed to compare the quality of life (QOL) of patients, clinical results of the recipient site, and morbidities of the donor site between the use of free anterolateral thigh flaps (ALTFs) and radial forearm flaps (RFFs) for reconstruction of full cheek defects following tumor resection. MATERIALS AND METHODS: We retrospectively reviewed 52 patients who underwent reconstruction of full cheek defects using free ALTFs and free RFFs following tumor ablation at our center. The range of mouth opening, speech, swallowing, facial appearance, donor site complications, and subjective symptoms based on the University of Washington Quality of Life (UW-QOL) questionnaire findings were assessed in the ALTF and RFF groups at 3, 12, and 36 months after surgery. RESULTS: Quality of life, range of mouth opening, facial appearance, mood and anxiety, donor site appearance, subjective feeling, and functional impairment were better in the ALTF group than in the RFF group based on the physical examination findings and questionnaire scores. CONCLUSION: This study found better QOL and better functional results at the recipient site and minor morbidities at the donor site with the use of free ALTFs in the reconstruction of full cheek defects.

Haploinsufficiency of hnRNP U Changes Activity Pattern and Metabolic Rhythms.

The neuropeptides arginine vasopressin (Avp) and vasoactive intestinal polypeptide (Vip) are critical for the communication and coupling of suprachiasmatic nucleus neurons, which organize daily rhythms of physiology and behavior in mammals. However, how these peptides are regulated remains uncharacterized. We found that heterogeneous nuclear ribonucleoprotein U (hnRNP U) is essential for the expression of Avp and Vip. Loss of one copy of the Hnrnpu gene resulted in fragmented locomotor activities and disrupted metabolic rhythms. Hnrnpu+/- mice were more active than wild-type mice in the daytime but more inactive at night. These phenotypes were partially rescued by microinfusion of Avp and Vip into free-moving animals. In addition, hnRNP U modulated Avp and Vip via directly binding to their promoters together with brain and muscle Arnt-like protein-1/circadian locomotor output cycles kaput heterodimers. Our work identifies hnRNP U as a novel regulator of the circadian pacemaker and provides new insights into the mechanism of rhythm output.

Upregulation of lncRNA ADAMTS9-AS2 Promotes Salivary Adenoid Cystic Carcinoma Metastasis via PI3K/Akt and MEK/Erk Signaling.

Neurotropic infiltrative growth and distant metastasis are the main causes of death in salivary adenoid cystic carcinoma (SACC) patients. Long noncoding RNAs (lncRNAs) are involved in many human neoplasms, however, their potential roles in SACC are unclear. In our study, we found that ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2) was significantly upregulated in SACC patients with metastasis and SACC-lung metastasis (LM) cells. Moreover, ADAMTS9-AS2 expression was closely associated with the prognosis and distant metastasis in SACC patients. Next, we found that c-myc could specifically bind to the promoter of ADAMTS9-AS2 and activated its transcription. Knockdown of ADAMTS9-AS2 significantly inhibited migration and invasion of SACC cells in vitro and distant lung metastasis in vivo. Furthermore, ADAMTS9-AS2, which mainly expressed in the cytoplasm, shared microRNA (miRNA) response elements with Integrin α6 (ITGA6). Overexpression of ADAMTS9-AS2 competitively bound to miR-143-3p that inhibited ITGA6 from miRNA-mediated degradation, and thus it activated the activity of PI3K/Akt and MEK/Erk signaling and facilitated SACC metastasis. In summary, ADAMTS9-AS2 promotes migration and invasion in SACC by competing with miR-143-3p. This sheds a new insight into the regulation mechanism of ADAMTS9-AS2, and it provides a possible application for the SACC treatment.

Chemotherapy-Induced Long Non-coding RNA 1 Promotes Metastasis and Chemo-Resistance of TSCC via the Wnt/ß-Catenin Signaling Pathway.

Increasing evidence has shown that chemo-resistance is related to the process of epithelial-mesenchymal transition (EMT) and increased invasiveness by tongue squamous cell carcinoma (TSCC) cells. Long non-coding RNAs (lncRNAs) play pivotal roles in tumor metastasis and progression. However, the roles and mechanisms of lncRNAs in cisplatin-resistance-induced EMT and metastasis are not well understood. In this study, a chemotherapy-induced lncRNA 1 (CILA1) was discovered by using microarrays and was functionally identified as a regulator of chemo-sensitivity in TSCC cells. Upregulation of CILA1 promotes EMT, invasiveness, and chemo-resistance in TSCC cells, whereas the inhibition of CILA1 expression induces mesenchymal-epithelial transition (MET) and chemo-sensitivity, and inhibits the invasiveness of cisplatin-resistant cells both in vitro and in vivo. We also found that CILA1 exerts its functions via the activation of the Wnt/ß-catenin signaling pathway. High CILA1 expression levels and low levels of phosphorylated ß-catenin were closely associated with cisplatin resistance and advanced disease stage, and were predictors of poor prognosis in TSCC patients. These findings provided a new biomarker for the chemo-sensitivity of TSCC tumors and a therapeutic target for TSCC treatment.

Gastric Bypass Surgery Reverses Diabetic Phenotypes in Bdnf-Deficient Mice.

Duodenum-jejunum gastric bypass (DJB) has been used to treat morbid diabetic patients. However, neither the suitability among patients nor the mechanisms of this surgical treatment is clear. Previously, we reported a new mouse strain named Timo as type 2 diabetes model caused by brain-derived neurotrophic factor (Bdnf) deficiency. In this study, we found that DJB on Timo mice reversed their metabolic abnormalities without altering the expression of Bdnf. Glucose tolerance and insulin sensitivity were improved greatly, along with reduction of fat accumulation in liver and white adipose tissue. The gut flora population was altered by DJB with increased proportion of Firmicutes and decreased Actinobacteria and Proteobacteria in the ileum after surgery. Systemic inflammation in Timo mice was greatly suppressed with less macrophage infiltration and lower tumor necrosis factor-α levels in liver and white adipose tissue after surgery. Interestingly, the alteration of gut microflora abundance and improved metabolism preceded the inflammation alleviation after DJB surgery. These results suggested that DJB can reverse Bdnf deficiency-associated metabolic abnormality. In addition, the reduced inflammation may not be the initial cause for the DJB-associated metabolic and microbiota alterations. The increased BDNF protein levels in hypothalamus and hippocampus may result from microbiota change after DJB surgery.

Endoscope-assisted extracapsular dissection of benign parotid tumors through a single cephaloauricular furrow incision versus a conventional approach.

BACKGROUND: A few modified approaches have been reported for performing endoscope-assisted dissections of benign parotid tumors, but none that use incisions totally hidden in a natural furrow. This study evaluated the feasibility of performing endoscope-assisted extracapsular dissections of benign parotid tumors using a single cephaloauricular furrow incision. METHODS: Forty-six patients with benign parotid superficial lobe tumors were randomly divided into two groups: an endoscope-assisted (21 patients) group or a conventional (25 patients) surgery group. Perioperative and postoperative outcomes of the patients were evaluated, including the maximum diameter of the tumors, length of the incision, operating time, estimated blood loss during the operation, amount and duration of drainage, satisfaction scores based on the cosmetic results, perioperative complications, and follow-up information. RESULTS: The diameters of the tumors were comparable between the groups, and all operations were successfully performed as planned. The mean length of the incision in the endoscope-assisted group (3.6 ± 0.5 cm) was significantly shorter than that in the conventional group (9.1 ± 1.9). Meanwhile, the intraoperative blood loss, amount of drainage, perioperative complications, and cosmetic outcomes were all improved in the endoscope-assisted group. No tumor recurrence was found during 11-40 months of follow-up. CONCLUSIONS: Cephaloauricular furrow incisions were totally and naturally hidden in this procedure. Endoscope-assisted extracapsular dissections of benign parotid tumors via a small cephaloauricular furrow incision were found to be feasible and reliable, providing a minimally invasive approach and a satisfactory appearance.