Deprivation of methionine inhibits osteosarcoma growth and metastasis via C1orf112-mediated regulation of mitochondrial functions.

Osteosarcoma is a malignant bone tumor that primarily inflicts the youth. It often metastasizes to the lungs after chemotherapy failure, which eventually shortens patients' lives. Thus, there is a dire clinical need to develop a novel therapy to tackle osteosarcoma metastasis. Methionine dependence is a special metabolic characteristic of most malignant tumor cells that may offer a target pathway for such therapy. Herein, we demonstrated that methionine deficiency restricted the growth and metastasis of cultured human osteosarcoma cells. A genetically engineered Salmonella, SGN1, capable of overexpressing an L-methioninase and hydrolyzing methionine led to significant reduction of methionine and S-adenosyl-methionine (SAM) specifically in tumor tissues, drastically restricted the growth and metastasis in subcutaneous xenograft, orthotopic, and tail vein-injected metastatic models, and prolonged the survival of the model animals. SGN1 also sharply suppressed the growth of patient-derived organoid and xenograft. Methionine restriction in the osteosarcoma cells initiated severe mitochondrial dysfunction, as evident in the dysregulated gene expression of respiratory chains, increased mitochondrial ROS generation, reduced ATP production, decreased basal and maximum respiration, and damaged mitochondrial membrane potential. Transcriptomic and molecular analysis revealed the reduction of C1orf112 expression as a primary mechanism underlies methionine deprivation-initiated suppression on the growth and metastasis as well as mitochondrial functions. Collectively, our findings unraveled a molecular linkage between methionine restriction, mitochondrial function, and osteosarcoma growth and metastasis. A pharmacological agent, such as SGN1, that can achieve tumor specific deprivation of methionine may represent a promising modality against the metastasis of osteosarcoma and potentially other types of sarcomas as well.

FKBP38 suppresses endometrial cancer cell proliferation and metastasis by inhibiting the mTOR pathway.

Endometrial cancer (EC) is a common gynecological malignancy, and advanced-stage or recurrent EC is associated with a high mortality rate owing to the ineffectiveness of currently available treatments. FK506-binding protein 38 (FKBP38) is a member of the immunophilin family and inhibits melanoma and breast cancer cell metastasis. However, the functions of FKBP38 and its potential mechanism in EC remain unclear. Herein, we analyzed the expression levels of FKBP38 in EC cells and found that the FKBP38 expression was high in Ishikawa cells, and low in AN3CA cells, traditionally considered a low grade and a high grade cell line, respectively, in pathology classification. Moreover, FKBP38 inhibited cell proliferation, migration and invasion in EC cells, FKBP38 knockdown significantly promoted tumor growth of Ishikawa cells in a subcutaneous xenograft model and increased the number of lung metastases of Hec-1-A cells in a metastatic mouse model. Furthermore, FKBP38 suppressed several target proteins of epithelial-to-mesenchymal transition (EMT) and reduced the phosphorylation of ribosomal S6 protein (S6), eukaryotic initiation factor 4E-binding protein 1 (4EBP-1), indicating the potent inhibition of the mammalian target of rapamycin (mTOR) pathway. Meanwhile, the inhibition of mTOR neutralized the elevation of EC cell proliferation, migration and invasion after FKBP38 knockdown. In summary, FKBP38 would exert a tumor-suppressing role by modulating the mTOR pathway. Our results indicate that FKBP38 may be considered as a factor of EC metastasis and a new target for EC therapeutic intervention.

Pediatric preseptal and orbital cellulitis - a 6 year experience from a London tertiary centre.

PURPOSE: This study reports the experience of pediatric preseptal and orbital cellulitis at a London tertiary centre during a 6-year period and highlights the role of orbital surgeons in the management of subperiosteal abscess (SPA). METHODS: A retrospective review was conducted of all pediatric patients hospitalised for preseptal and orbital cellulitis. RESULTS: A total of 201 children including 152 cases of preseptal cellulitis and 49 cases of orbital cellulitis were admitted at a London tertiary centre over the study period. Patients with orbital cellulitis and especially those managed surgically had higher rates of fever, higher presenting white cell count and C-reactive protein level compared to cases of preseptal cellulitis. 77.6% of patients with orbital cellulitis had SPA. 81.6% of SPA had a medial component, while 28.9% had superior component. 61.2% of orbital cellulitis cases were managed surgically. Surgical intervention was carried out by otorhinolaryngologists (ENT) in 76.7% of cases, jointly between ENT and orbital surgeons in 16.7% of cases and by orbital surgeons alone in 6.7% of cases. Of the 11 SPA involving the orbital roof, all were surgically managed and orbital surgeons were involved in 54.5% of cases. When SPA involved the medial wall, orbital surgeons were only involved in 6.5% of cases. CONCLUSIONS: We recommend all patients with superior SPA be treated at a centre with both ENT and orbital surgeons as these may not be amenable to drainage by ENT alone.

Prognosis prediction based on methionine metabolism genes signature in gliomas.

BACKGROUND: Glioma cells have increased intake and metabolism of methionine, which can be monitored with 11 C-L-methionine. However, a short half-life of 11 C (~ 20 min) limits its application in clinical practice. It is necessary to develop a methionine metabolism genes-based prediction model for a more convenient prediction of glioma survival. METHODS: We evaluated the patterns of 29 methionine metabolism genes in glioma from the Cancer Genome Atlas (TCGA). A risk model was established using Lasso regression analysis and Cox regression. The reliability of the prognostic model was validated in derivation and validation cohorts (Chinese Glioma Genome Atlas; CGGA). GO, KEGG, GSEA and ESTIMATE analyses were performed for biological functions and immune characterization. RESULTS: Our results showed that a majority of the methionine metabolism genes (25 genes) were involved in the overall survival of glioma (logrank p and Cox p < 0.05). A 7-methionine metabolism prognostic signature was significantly related to a poor clinical prognosis and overall survival of glioma patients (C-index = 0.83). Functional analysis revealed that the risk model was correlated with immune responses and with epithelial-mesenchymal transition. Furthermore, the nomogram integrating the signature of methionine metabolism genes manifested a strong prognostic ability in the training and validation groups. CONCLUSIONS: The current model had the potential to improve the understanding of methionine metabolism in gliomas and contributed to the development of precise treatment for glioma patients, showing a promising application in clinical practice.

Combined upper lid skin crease and endoscopic approach to frontal sinus mucocoeles.

PURPOSE: This case series describes the ophthalmic manifestations of frontal sinus mucoceles and reports the long-term surgical outcomes of a combined endoscopic and upper-lid skin crease drainage approach carried out jointly with otorhinolaryngology. METHODS: We present a retrospective case review of 18 orbits and 15 patients presenting with frontal sinus mucocoeles, all of whom underwent drainage via an adapted anterior orbitotomy approach between January 2015 and July 2023. Data collection included preoperative and postoperative examination findings (visual acuity, extraocular motility, lid retraction, and lagophthalmos), mucocoele recurrence, cosmetic satisfaction, and surgical complications. Patients were followed up for an average of 22 months. RESULTS: All patients underwent successful frontal mucocoele drainage via a modified anterior orbitotomy and simultaneous endonasal approach. At presentation, three (20%) had extraocular restriction leading to diplopia, and six (40%) had proptosis in the eye adjacent to the mucocoele. One patient presented acutely with no light perception in the affected eye due to compressive optic neuropathy. All patients who had reduced extraocular motility before surgery regained full motility post-operatively. Treatment was successful in all cases, and there was no documented mucocoele recurrence during follow-up. Satisfactory aesthetic outcomes were achieved in all cases. Reported complications included temporary forehead numbness and ptosis of the affected eyelid, which resolved without intervention. CONCLUSION: The modified anterior orbitotomy approach to frontal mucocoeles allows optimal frontal sinus access and mucocoele treatment while preserving cosmesis.

A multidisciplinary approach to frontal sinus mucocoeles using an upper lid skin crease incision combined with endoscopic drainage allows full access to the frontal sinus and treatment of the mucocoele while preserving cosmesis.

Horizontal eyelid shortening alone versus combined procedures for the correction of involutional lower eyelid entropion.

BACKGROUND: Conventionally, management of involutional entropion involves correcting both vertical and horizontal laxity, however the optimal surgical approach is debated. OBJECTIVE: To compare the recurrence rate of horizontal lower eyelid shortening alone with combined surgical approaches for correction of involutional lower eyelid entropion. METHODS AND MATERIAL: A retrospective, comparative, consecutive case series of patients undergoing surgery for involutional lower eyelid entropion with both horizontal and vertical laxity. Patients were categorized based on the procedure as: Group 1, horizontal shortening alone, Group 2, horizontal shortening with everting sutures), and Group 3, horizontal shortening with retractor plication. RESULTS: Of the 249 procedures (31 bilateral) performed on 218 patients, 54 (22%) involved horizontal eyelid shortening alone (Group 1), while 80 (32%) had this combined with everting sutures (Group 2), and 115 (46%) with retractor plication (Group 3). The anatomical success rates for Groups 1, 2, and 3 were 93, 94, and 90% (P = 0.69), respectively. Similarly, reported symptom improvements were 94, 93, and 93% for these groups (P = 0.91). After an average follow-up of 15.7 months (median 10; range 6-81), Group 1 (eyelid shortening alone) had a 7% (4/54) recurrence, compared to 8% (16/195) in Groups 2 and 3 (combined procedures) (P = 1.0). Complications were minor, with no significant difference between groups. CONCLUSION: Eyelid shortening alone appears to be as effective as combined techniques for involutional entropion with both horizontal and vertical eyelid laxity. Nevertheless, procedure selection should consider primary pathogenic factors.

Canalicular obstruction associated with dupilumab.

PURPOSE: Dupilumab is a novel treatment for severe atopic dermatitis and is associated with a range of ocular complications such as blepharoconjunctivitis, keratitis, cicatricial ectropion and punctal stenosis. METHODS: We report 4 patients with canalicular obstruction in association with dupilumab therapy, and we describe their treatment and outcomes in each case. RESULTS: Canalicular obstruction was diagnosed by an oculoplastic consultant between 3 years and 3 months and 4 years and 9 months after the commencement of dupilumab therapy. Case 1 underwent nasolacrimal intubation, case 2 was treated conservatively, and case 4 underwent endonasal dacryocystorhinostomy and these patients' symptoms resolved. Unfortunately, in case 3 despite endonasal dacryocystorhinostomy with stenting they remained symptomatic. CONCLUSION: This case series adds to the growing number of ocular complications associated with dupilumab therapy, and there is yet an optimal treatment strategy to mitigate these complications. It is possible that simple conservative measures such as discontinuation of dupilumab and topical treatments with steroids can eventually lead to some form of recovery and recanalisation of the canalicular system. Early referral to an ophthalmologist prior to the development of canalicular obstruction to control the inflammatory ocular surface could reduce the risks of cicatricial sequelae from dupilumab, and temporary stenting of the canalicular system could be attempted as a method to keep the canalicular system patent, whilst the patient remained on treatment.

Targeted deprivation of methionine with engineered Salmonella leads to oncolysis and suppression of metastasis in broad types of animal tumor models.

The strong dependency of almost all malignant tumors on methionine potentially offers a pathway for cancer treatment. We engineer an attenuated strain of Salmonella typhimurium to overexpress an L-methioninase with the aim of specifically depriving tumor tissues of methionine. The engineered microbes target solid tumors and induce a sharp regression in several very divergent animal models of human carcinomas, cause a significant decrease in tumor cell invasion, and essentially eliminate the growth and metastasis of these tumors. RNA sequencing analyses reveal that the engineered Salmonella reduce the expression of a series of genes promoting cell growth, cell migration, and invasion. These findings point to a potential treatment modality for many metastatic solid tumors, which warrants further tests in clinical trials.

Pharmacological targeting of type phosphodiesterase 4 inhibits the development of acute myeloid leukemia by impairing mitochondrial function through the Wnt/ß-catenin pathway.

Acute myeloid leukemia (AML) is prone to drug-resistant relapse with a low 5-year survival rate. New therapeutic modalities are sorely needed to provide hope for AML relapse patients. Herein, we demonstrated a specific inhibitor of type 4 phosphodiesterase (PDE4), Zl-n-91, could significantly reduce the proliferation of AML cells, block DNA replication process, and increase AML cell death. Zl-n-91 also impeded the growth of subcutaneous xenograft and prolonged the survival of the MLL-AF9-driven AML model. Bioinformatic analysis revealed that elevated mitochondrial gene signatures inversely correlate with the survival of AML patients; and importantly, Zl-n-91 strongly suppressed the function of mitochondria. In addition, this PDE4 inhibitor induced alterations in multiple signaling pathways, including the reduction of ß-catenin activity. Stimulation of the Wnt/ß-catenin pathway could attenuate the inhibitory effect of Zl-n-91 on AML cell proliferation as well as mitochondrial function. Taken together, we revealed for the first time that targeting PDE4 activity could attenuate mitochondrial function through a Wnt/ß-catenin pathway, which in turn would block the growth of AML cells. Specific PDE4 inhibitors can potentially serve as a new treatment modality for AML patients.

Resistin Promotes Nasopharyngeal Carcinoma Metastasis through TLR4-Mediated Activation of p38 MAPK/NF-κB Signaling Pathway.

NPC is a type of malignant tumor with a high risk of local invasion and early distant metastasis. Resistin is an inflammatory cytokine that is predominantly produced from the immunocytes in humans. Accumulating evidence has suggested a clinical association of circulating resistin with the risk of tumorigenesis and a relationship between blood resistin levels and the risk of cancer metastasis. In this study, we explored the blood levels and the role of resistin in NPC. High resistin levels in NPC patients were positively associated with lymph node metastasis, and resistin promoted the migration and invasion of NPC cells in vitro. These findings were also replicated in a mouse model of NPC tumor metastasis. We identified TLR4 as a functional receptor in mediating the pro-migratory effects of resistin in NPC cells. Furthermore, p38 MAPK and NF-κB were intracellular effectors that mediated resistin-induced EMT. Taken together, our results suggest that resistin promotes NPC metastasis by activating the TLR4/p38 MAPK/NF-κB signaling pathways.

ZL-n-91, a specific Phosphodiesterase-4 inhibitor, suppresses the growth of triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that frequently develops resistance to chemotherapy. A new approach to treating TNBC is required to improve patient survival. Phosphodiesterase-4 (PDE4) is an enzyme that is predominantly involved in the modulation of intracellular signaling mediated by cAMP. Although the efficacy of PDE4 inhibitors in several human inflammatory diseases is well documented, their clinical utility has been limited by side effects, including nausea and emesis. Recently, PDE4 has been used as a potential therapeutic target for different cancer types. In the present study, we investigated the anticancer effects of a novel PDE4 inhibitor ZL-n-91 on TNBC and the underlying mechanism. We showed that ZL-n-91 inhibited the proliferation of TNBC cells, induced cell apoptosis, and caused cell cycle arrest. Western blot analysis showed that ZL-n-91 increased Bax level and reduced Bcl-2 expression. Furthermore, downregulation of the cell cycle-related proteins, such as CDK2, CDK4, cyclin D1, PCNA, p-RB, and ZL-n-91, significantly inhibited the transcription of DNA repair genes and triggered an intracellular DNA damage response. Moreover, ZL-n-91 prevented the growth of the transplanted MDA-MB-231 tumor xenograft in nude mice and increased the γ-H2AX expression. These data demonstrate the anticancer effects of ZL-n-91 on TNBC cells and suggest its potential use in anticancer therapy.

Adiponectin deficiency promotes endometrial carcinoma pathogenesis and development via activation of mitogen-activated protein kinase.

Obesity is one of the major risk factors for cancer. Clinical studies have demonstrated that circulating levels of adiponectin are inversely correlated, not only with the extent of adiposity, but also with the incidence of several types of cancer, particularly endometrial cancer (EC). However, thus far, adiponectin remains a correlative factor, without definitive evidence to show a causal effect in EC and the potential mechanism(s) involved. To address this issue, we introduced an Apn-null mutation into Pten haploid-deficient (Pten+/- ) mice. The Pten heterozygous mutation alone led to the development of EC in less than 30% of female mice; however, when combined with the Apn-null mutation, the incidence of endometrial lesions rose to at least two-thirds. Although Apn deficiency did not further potentiate the Akt activation caused by the Pten mutation, it elevated the phosphorylation of mitogen-activated protein kinase (MAPK) p42/44, indicating activation of the MAPK signaling pathway. Treatment of Apn-/- ;Pten+/- mice with a MEK inhibitor blocked the development of EC. Finally, xenografts of a PTEN-proficient human EC cell line grew faster in Apn-deficient mice, whereas an adiponectin receptor agonist reduced xenograft growth of a PTEN-deficient human EC cell line. Thus, reduction of adiponectin activity promotes EC development, at least in the context of Pten mutation, by activating MAPK. © 2022 The Pathological Society of Great Britain and Ireland.

Genetic ablation of C-reactive protein gene confers resistance to obesity and insulin resistance in rats.

AIMS/HYPOTHESIS: Besides serving as a traditional inflammatory marker, C-reactive protein (CRP) is closely associated with the development of obesity, diabetes and cardiovascular diseases as a metabolic and inflammatory marker. We hypothesise that CRP protein directly participates in the regulation of energy and glucose metabolism rather than just being a surrogate marker, and that genetic deficiency of CRP will lead to resistance to obesity and insulin resistance. METHODS: Crp gene deletion was achieved by transcription activator-like effector nuclease (TALEN) technology in rats. The Crp knockout animals were placed on either a standard chow diet or a high-fat diet. Phenotypic changes in body weight, glucose metabolism, insulin sensitivity, energy expenditure and inflammation condition were examined. The central impact of CRP deficiency on leptin and insulin hypothalamic signalling, as well as glucose homeostasis, were examined via intracerebral ventricular delivery of leptin and CRP plus glucose clamp studies in the wild-type and Crp knockout rats. RESULTS: CRP deficiency led to a significant reduction in weight gain and food intake, elevated energy expenditure and improved insulin sensitivity after exposure to high-fat diet. Glucose clamp studies revealed enhanced hepatic insulin signalling and actions. Deficiency of CRP enhanced and prolonged the weight-reducing effect of central injected leptin and promoted the central and peripheral roles of leptin. By contrast, reinstatement of CRP into the hypothalamus of the knockout rats attenuated the effects of central leptin signalling on insulin sensitivity and peripheral glucose metabolism. CONCLUSIONS/INTERPRETATION: This study represents the first line of genetic evidence that CRP is not merely a surrogate blood marker for inflammation and metabolic syndromes but directly regulates energy balance, body weight, insulin sensitivity and glucose homeostasis through direct regulation of leptin's central effect and hypothalamic signalling.

Left ventricular systolic ejection time is an independent predictor of all-cause mortality in heart failure with reduced ejection fraction.

AIMS: Colour tissue Doppler imaging (TDI) M-mode through the mitral leaflet is an easy and precise method to obtain cardiac time intervals including isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT) and systolic ejection time (SET). The myocardial performance index (MPI) is defined as [(IVCT + IVRT)/SET]. Whether cardiac time intervals obtained by the TDI M-mode method can be used to predict outcome in patients with heart failure with reduced ejection fraction (HFrEF) remains unknown. METHODS AND RESULTS: A total of 997 patients with HFrEF (mean age 67 ± 11 years, 74% male) underwent an echocardiographic examination including TDI. During a median follow-up of 3.4 years (interquartile range 1.9-4.8 years), 165 (17%) patients died. The risk of mortality increased by 9% per 10 ms decrease in SET [per 10 ms decrease: hazard ratio (HR) 1.09, 95% confidence interval (CI) 1.06-1.13; P < 0.001]. The association remained significant even after multivariable adjustment for clinical and echocardiographic parameters (per 10 ms decrease: HR 1.06, 95% CI 1.01-1.11; P = 0.030). The MPI was a significant predictor in an unadjusted model (per 0.1 increase: HR 3.06, 95% CI 1.16-8.06; P = 0.023). However, the association did not remain significant after multivariable adjustment. No significant associations between IVCT or IVRT and mortality were found in unadjusted nor adjusted models. Additionally, SET provided incremental prognostic information with regard to predicting mortality when added to established clinical predictors of mortality in patients with HFrEF. CONCLUSION: In patients with HFrEF, SET provides independent and incremental prognostic information regarding all-cause mortality.

Inhibition of acute leukemia with attenuated Salmonella typhimurium strain VNP20009.

Acute leukemia is a common hematological malignancy. Despite recent promising progress, the prognosis of acute leukemia patients remains to be improved. New therapies are therefore still needed. Salmonella typhimurium has been shown to be highly effective as an anti-tumor agent in many solid cancer models, but it has not been applied in acute leukemia. Here, we report an attenuated Salmonella typhimurium strain, VNP20009, can induce apoptosis in multiple types of leukemia cells both in vivo and in vitro. Furthermore, VNP20009 significantly inhibited the proliferation of MLL-AF9-induced acute myeloid leukemia cells and prolonged the survival of the AML-carrying mice. VNP20009 restored the counts of white blood cell (WBC) and its five subsets in peripheral blood (PB) to near-physiological values, and elevated the levels of certain cytokines, such as tumor necrosis factor-α (TNF-α), leukemia inhibitory factor (LIF), interferon-γ (IFN-γ), chemokine C-X-C motif ligand-10 (CXCL-10) and C-C motif ligand-2 (CCL-2). Moreover, the ratio of immune cells, including natural killer cells (NKs), CD4+ Th1-type cells and CD8+ IFN-γ-producing effector T cells were highly upregulated in the AML mice treated with VNP20009. The results of the present study potentially provide an alternative therapeutic strategy for hematologic malignancies through boosting the innate and adaptive anti-tumor immunity.

Cellular apoptosis susceptibility protein (CAS) suppresses the proliferation of breast cancer cells by upregulated cyp24a1.

Breast cancer is the most common cancer in women. Although several studies demonstrated cellular apoptosis susceptibility protein (CAS) involved in the development of breast cancer, the underlying mechanisms of CAS regulating cell processes in the breast cancer remain elusive. In the present study, we explored the possible mechanism of CAS in contributing to the cell proliferation in the breast cancer cell line MCF-7. Knockdown of CAS led to the reduction of cell viability and proliferation. Furthermore, cell cycle was arrested in G0/G1 phase after knocking down CAS with the decrease of cyclinD1. In addition, RNA-seq analysis for the CAS knockdown cells demonstrated that total eleven genes were significantly altered (Fold changes > 2). Of note, the expression of cyp24a1 was dramatically increased in the shCAS cells compared to that of shNC cells as well as confirmed by quantitative real-time polymerase chain reaction (qPCR). These observations clarified the previous conflicting results on the cell fates of the breast cells regulated by CAS and provide new insight into the role of CAS in the development of breast cancer.

Impairment of spermatogenesis and sperm motility by the high-fat diet-induced dysbiosis of gut microbes.

OBJECTIVE: High-fat diet (HFD)-induced metabolic disorders can lead to impaired sperm production. We aim to investigate if HFD-induced gut microbiota dysbiosis can functionally influence spermatogenesis and sperm motility. DESIGN: Faecal microbes derived from the HFD-fed or normal diet (ND)-fed male mice were transplanted to the mice maintained on ND. The gut microbes, sperm count and motility were analysed. Human faecal/semen/blood samples were collected to assess microbiota, sperm quality and endotoxin. RESULTS: Transplantation of the HFD gut microbes into the ND-maintained (HFD-FMT) mice resulted in a significant decrease in spermatogenesis and sperm motility, whereas similar transplantation with the microbes from the ND-fed mice failed to do so. Analysis of the microbiota showed a profound increase in genus Bacteroides and Prevotella, both of which likely contributed to the metabolic endotoxaemia in the HFD-FMT mice. Interestingly, the gut microbes from clinical subjects revealed a strong negative correlation between the abundance of Bacteroides-Prevotella and sperm motility, and a positive correlation between blood endotoxin and Bacteroides abundance. Transplantation with HFD microbes also led to intestinal infiltration of T cells and macrophages as well as a significant increase of pro-inflammatory cytokines in the epididymis, suggesting that epididymal inflammation have likely contributed to the impairment of sperm motility. RNA-sequencing revealed significant reduction in the expression of those genes involved in gamete meiosis and testicular mitochondrial functions in the HFD-FMT mice. CONCLUSION: We revealed an intimate linkage between HFD-induced microbiota dysbiosis and defect in spermatogenesis with elevated endotoxin, dysregulation of testicular gene expression and localised epididymal inflammation as the potential causes. TRIAL REGISTRATION NUMBER: NCT03634644.