Butylparaben induced zebrafish (Danio rerio) kidney injury by down-regulating the PI3K-AKT pathway.

Butylparaben, a common endocrine disruptor in the environment, is known to be toxic to the reproductive system, heart, and intestines, but its nephrotoxicity has rarely been reported. In order to study the nephrotoxicity and mechanism of butylparaben, we examined the acute and chronic effects on human embryonic kidney cells (HEK293T) and zebrafish. Additionally, we assessed the potential remedial effects of salidroside against butylparaben-induced nephrotoxicity. Our in vitro findings demonstrated oxidative stress and cytotoxicity to HEK293T cells caused by butylparaben. In the zebrafish model, the concentration of butylparaben exposure ranged from 0.5 to 15 µM. An assortment of experimental techniques was employed, including the assessment of kidney tissue morphology using Hematoxylin-Eosin staining, kidney function analysis via fluorescent dextran injection, and gene expression studies related to kidney injury, development, and function. Additionally, butylparaben caused lipid peroxidation in the kidney, thereby damaging glomeruli and renal tubules, which resulted from the downregulation of the PI3K-AKT signaling pathway. Furthermore, salidroside ameliorated butylparaben-induced nephrotoxicity through the PI3K-AKT signaling pathway. This study reveals the seldom-reported kidney toxicity of butylparaben and the protective effect of salidroside against toxicological reactions related to nephrotoxicity. It offers valuable insights into the risks to kidney health posed by environmental toxins.

Adjuvant activity of cordycepin, a natural derivative of adenosine from Cordyceps militaris, on an inactivated rabies vaccine in an animal model.

Vaccination is the most feasible way of preventing rabies, an ancient zoonosis that remains a major public health concern globally. However, administration of inactivated rabies vaccination without adjuvants is always inefficient and necessitates four to five injections. In the current study, we explored the adjuvant characteristics of cordycepin, a major bioactive component of Cordyceps militaris, to boost immune responses against a commercially available rabies vaccine. We found that cordycepin could stimulate stronger phenotypic and functional maturation of dendritic cells (DCs). For animal experiments, mice were immunized 3 times with rabies vaccine in the presence or absence of cordycepin at 1-week interval. Analysis of T cell differentiation and serum antibody isotypes showed that humoral immunity was dominant with a Th2 biased immune response. These results were also supported by the raised ratio of follicular helper T cells (TFH) and germinal center B cells (GCB). Thus, titer of rabies virus neutralizing antibody (RVNAb) and rabies virus-specific memory B cells were both raised as a result. Furthermore, administration of cordycepin did not cause pathological phenomena or body weight loss. The findings indicate that cordycepin could be used as a promising adjuvant for rabies vaccines to get a higher range of protection without any side effects.

ETS2 overexpression ameliorates cartilage injury in osteoarthritis by the ETS2/miR-155/STAT1/DNMT1 feedback loop pathway.

Osteoarthritis (OA) is the most common irreversible chronic joint dysfunction disease, which is pathologically characterized by disturbance of articular cartilage homeostasis leading to subsequent inflammatory response and cartilage extracellular matrix (ECM) degradation. Increasing evidence has demonstrated the dysregulation of transcription factors play crucial roles in the occurrence and development of osteoarthritis (OA), but the potential functions and mechanism of most transcription factors in OA has not been completely illuminated. In this study, we identified that transcription factor V-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2) was significantly down-regulated in OA cartilage and IL-1ß-induced OA chondrocytes. Functional experiments in vitro demonstrated that the overexpressed ETS2 strikingly enhanced proliferation, outstandingly suppressed apoptosis, and dramatically reduced inflammation and ECM degradation in IL-1ß-induced OA chondrocytes, whereas the knockdown of ETS2 led to the opposite effects. Further in vivo studies have shown that up-regulated ETS2 dramatically ameliorates cartilage injury in DMM-induced OA mice. Mechanical studies have disclosed that DNMT1-mediated downregulation of ETS2 dramatically promotes STAT1 by inhibiting miR-155 transcription, and increased STAT1 initiates a feedback loop that may enhance DNMT1-mediated hypermethylation of ETS2 to inhibit ETS2 expression, thus forming a DNMT1/ETS2/miR-155/STAT1 feedback loop that inhibits MAPK signaling pathways and aggravates OA cartilage injury. In all, our results revealed that overexpression of ETS2 markedly ameliorated OA cartilage injury through the ETS2/miR-155/STAT1/DNMT1 feedback loop, providing a new perspective on the pathogenesis and therapeutic strategies for OA.

Advances in the Biological Functions and Mechanisms of miRNAs in the Development of Osteosarcoma.

Osteosarcoma is one of the most common primary malignant bone tumors, mainly occurring in children and adolescents, and is characterized by high morbidity and poor prognosis. MicroRNAs, a class of noncoding RNAs consisting of 19 to 25 nucleotides, are involved in cell proliferation, invasion, metastasis, and apoptosis to regulate the development and progression of osteosarcoma. Studies have found that microRNAs are closely related to the diagnosis, treatment, and prognosis of osteosarcoma patients and have an important role in improving drug resistance in osteosarcoma. This paper reviews the role of microRNAs in the pathogenesis of osteosarcoma and their clinical value, aiming to provide a new research direction for diagnosing and treating osteosarcoma and achieving a better prognosis.

Novel Immunotherapies for Osteosarcoma.

Osteosarcoma (OS) is the most common primary malignant bone sarcoma mainly affecting adolescents and young adults, which often progresses to pulmonary metastasis and leads to the death of OS patients. OS is characterized as a highly heterogeneous cancer type and the underlying pathologic mechanisms triggering tumor progress and metastasis are incompletely recognized. Surgery combined with neoadjuvant and postoperative chemotherapy has elevated 5-year survival to over 70% for patients with localized OS tumors, as opposed to only 20% of patients with recurrence and/or metastasis. Therefore, novel therapeutic strategies are needed to overcome the drawbacks of conventional treatments. Immunotherapy is gaining momentum for the treatment of OS with an increasing number of FDA-approved therapies for malignancies resistant to conventional therapies. Here, we review the OS tumor microenvironment and appraise the promising immunotherapies available in the management of OS.

Bone remodeling following mandibular reconstruction using fibula free flap.

To investigate bone remodelling responses to mandibulectomy, a joint external and internal remodelling algorithm is developed here by incorporating patient-specific longitudinal data. The primary aim of this study is to simulate bone remodelling activity in the conjunction region with a fibula free flap (FFF) reconstruction by correlating with a 28-month clinical follow-up. The secondary goal of this study is to compare the long-term outcomes of different designs of fixation plate with specific screw positioning. The results indicated that the overall bone density decreased over time, except for the Docking Site (namely DS1, a region of interest in mandibular symphysis with the conjunction of the bone union), in which the decrease of bone density ceased later and was followed by bone apposition. A negligible influence on bone remodeling outcome was found for different screw positioning. This study is believed to be the first of its kind for computationally simulating the bone turn-over process after FFF maxillofacial reconstruction by correlating with patient-specific follow-up.

Epigenetic Inactivation of Acetyl-CoA Acetyltransferase 1 Promotes the Proliferation and Metastasis in Nasopharyngeal Carcinoma by Blocking Ketogenesis.

The dysregulation of epigenetic modification and energy metabolism cooperatively contribute to the tumorigenesis of nasopharyngeal carcinoma (NPC). However, the detailed mechanisms underlying their joint contribution to NPC development and progression remain unclear. Here, we investigate the role of Acy1 Coenzyme A Acyltransferases1 (ACAT1), a key enzyme in the metabolic pathway of ketone bodies, in the proliferation and metastasis of NPC and to elucidate the underlying molecular mechanisms. Ketogenesis, plays a critical role in tumorigenesis. Previously, we reported two enzymes involved in ketone body metabolism mediate epigenetic silencing and act as tumor suppressor genes in NPC. Here, we identify another key enzyme, Acetyl-CoA acetyltransferase 1 (ACAT1), and show that its transcriptional inactivation in NPC is due to promoter hypermethylation. Ectopic overexpression of ACAT1 significantly suppressed the proliferation and colony formation of NPC cells in vitro. The migratory and invasive capacity of NPC cells was inhibited by ACAT1. The tumorigenesis of NPC cells overexpressing ACAT1 was decreased in vivo. Elevated ACAT1 in NPC cells was accompanied by an elevated expression of CDH1 and a reduced expression of vimentin and SPARC, strongly indicating that ACAT1 is involved in regulating epithelial-mesenchymal transition (EMT). We also found that ACAT1 contributes to increased intracellular levels of ß-hydroxybutyrate (ß-HB). Exogenously supplied ß-HB significantly inhibits the growth of NPC cells in a dose-dependent manner. In summary, ACAT1 may function as a tumor suppressor via modulation of ketogenesis and could thus serve as a potential therapeutic target in NPC. In summary, our data suggest that regulation of ketogenesis may serve as adjuvant therapy in NPC.

Effects of buccal thickness augmentation on bone remodeling after maxillary anterior implantation.

The biomechanics associated with buccal bone thickness (BBT) augmentation remains poorly understood, as there is no consistent agreement in the adequate BBT to avoid over-loading resorption or over-augmenting surgical difficulty. This study utilizes longitudinal clinical image data to establish a self-validating time-dependent finite element (FE)-based remodeling procedure to explore the effects of different buccal bone thicknesses on long-term bone remodeling outcomes in silico. Based upon the clinical computed tomography (CT) scans, a patient-specific heterogeneous FE model was constructed to enable virtual BBT augmentation at four different levels (0.5, 1.0, 1.5, and 2.0 mm), followed by investigation into the bone remodeling behavior of the different case scenarios. The findings indicated that although peri-implant bone resorption decreased with increasing initial BBT from 0.5 to 2 mm, different levels of the reduction in bone loss were associated with the amount of bone augmentation. In the case of 0.5 mm BBT, overloading resorption was triggered during the first 18 months, but such bone resorption was delayed when the BBT increased to 1.5 mm. It was found that when the BBT reached a threshold thickness of 1.5 mm, the bone volume can be better preserved. This finding agrees with the consensus in dental clinic, in which 1.5 mm BBT is considered clinically justifiable for surgical requirement of bone graft. In conclusion, this study introduced a self-validating bone remodeling algorithm in silico, and it divulged that the initial BBT affects the bone remodeling outcome significantly, and a sufficient initial BBT is considered essential to assure long-term stability and success of implant treatment.

Knockdown Rab11-FIP2 inhibits migration and invasion of nasopharyngeal carcinoma via suppressing Rho GTPase signaling.

Rab11 family interacting protein 2 (Rab11-FIP2) is a conserved protein and effector molecule for the small GTPase Rab11. By interacting with Rab11 and MYO5B, Rab11-FIP2 regulates endosome trafficking of plasma membrane proteins, promoting cellular motility. The endosomal trafficking system in nasopharyngeal carcinoma (NPC) remains unclear. Here, an outlier analysis using the Oncomine database suggested that Rab11-FIP2 but not Rab11 and MYO5B was overexpressed in NPC. We confirmed that the transcription of Rab11-FIP2 was upregulated in NPC cell lines and primary tumor tissues as compared with a normal nasopharyngeal epithelial cell line and normal nasopharynx tissues. We further confirmed the elevated protein expression level of Rab11-FIP2 in NPC biopsies. Instead of regulating the epithelial-mesenchymal transition or Akt signaling pathway, knockdown of Rab11-FIP2 inhibited the migration and invasion ability of NPC cell lines by decreasing the expression of Rac and Cdc42. In summary, Rab11-FIP2 could be an oncogene in NPC, mainly contributing to metastatic capacity by activating Rho GTPase signaling.

Inactivation of 3-hydroxybutyrate dehydrogenase type 2 promotes proliferation and metastasis of nasopharyngeal carcinoma by iron retention.

BACKGROUND: 3-Hydroxybutyrate dehydrogenase type 2 (BDH2) is known to catalyse a rate-limiting step in the biogenesis of the mammalian siderophore and regulate intracellular iron metabolism. Here we aim to explore the expression and possible function of BDH2 in nasopharyngeal carcinoma (NPC). METHODS: The transcription and protein expression of BDH2 in NPC were determined by both real-time RT-PCR and immunohistochemistry staining assays. Cell proliferation, migration and invasion were evaluated by MTT assay, wound-healing assay and Transwell assay, respectively. The profile of genes regulated by restoring BDH2 expression in NPC cells was analysed by cDNA microarray. The level of iron in NPC cells was detected by iron colorimetric assay. RESULTS: The expression of BDH2 was significantly downregulated in NPC. Ectopic expression of BDH2 inhibited NPC cell proliferation and colony formation. Meanwhile, BDH2 suppressed the migration and invasion of NPC cells by reversing the epithelial-mesenchymal transition (EMT). In addition, a higher level of BDH2 decreased the growth and metastasis of NPC cells via reducing intracellular iron level. CONCLUSIONS: Our findings suggest that BDH2 may be a candidate tumour-suppressor gene in NPC. Decreasing intracellular iron could be an effective therapeutic approach for NPC.

A new xanthene-based fluorescent probe with a red light emission for selectively detecting glutathione and imaging in living cells.

Glutathione (GSH) is the most abundant low-molecular-weight cysteine-containing thiol in cells, which plays an essential role in many biological processes. Most reported fluorescent probes towards GSH possess short excitation and emission wavelength, which could result in low tissue penetration, high background fluorescence and photodamage to biological samples. Herein, a novel turn-on fluorescent probe (ADS) with the xanthene skeleton for GSH detection was developed based on a fluorophore, ACF-NH2. The probe had a red light emission (λem = 630 nm) and exhibited a good linear relationship for exogenous GSH (1-6 mM) and a good limit of detection (LOD: 13.1 µM, based on S/N = 3), which implied that it was possible to detect the change of GSH in the living cells (0.5-10 mM) by further structural modification. The probe displayed excellent selectivity for GSH over other analytes and good anti-interference ability. Moreover, cell viability assay indicated that ADS was biocompatible and exhibited very low cytotoxicity. A combination of mass spectrum analysis and density functional theory calculation was performed to explain the sensing mechanism of the probe. In addition, it was applied to image GSH in living cells successfully.

Investigation on masticatory muscular functionality following oral reconstruction - An inverse identification approach.

The human masticatory system has received significant attention in the areas of biomechanics due to its sophisticated co-activation of a group of masticatory muscles which contribute to the fundamental oral functions. However, determination of each muscular force remains fairly challenging in vivo; the conventional data available may be inapplicable to patients who experience major oral interventions such as maxillofacial reconstruction, in which the resultant unsymmetrical anatomical structure invokes a more complex stomatognathic functioning system. Therefore, this study aimed to (1) establish an inverse identification procedure by incorporating the sequential Kriging optimization (SKO) algorithm, coupled with the patient-specific finite element analysis (FEA) in silico and occlusal force measurements at different time points over a course of rehabilitation in vivo; and (2) evaluate muscular functionality for a patient with mandibular reconstruction using a fibula free flap (FFF) procedure. The results from this study proved the hypothesis that the proposed method is of certain statistical advantage of utilizing occlusal force measurements, compared to the traditionally adopted optimality criteria approaches that are basically driven by minimizing the energy consumption of muscle systems engaged. Therefore, it is speculated that mastication may not be optimally controlled, in particular for maxillofacially reconstructed patients. For the abnormal muscular system in the patient with orofacial reconstruction, the study shows that in general, the magnitude of muscle forces fluctuates over the 28-month rehabilitation period regardless of the decreasing trend of the maximum muscular capacity. Such finding implies that the reduction of the masticatory muscle activities on the resection side might lead to non-physiological oral biomechanical responses, which can change the muscular activities for stabilizing the reconstructed mandible.

Biomechanical analysis of bone remodeling following mandibular reconstruction using fibula free flap.

Whilst the newly established biomechanical conditions following mandibular reconstruction using fibula free flap can be a critical determinant for achieving favorable bone union, little has been known about their association in a time-dependent fashion. This study evaluated the bone healing/remodeling activity in reconstructed mandible and its influence on jaw biomechanics using CT data, and further quantified their correlation with mechanobiological responses through an in-silico approach. A 66-year-old male patient received mandibular reconstruction was studied. Post-operative CT scans were taken at 0, 4, 16 and 28 months. Longitudinal change of bone morphologies and mineral densities were measured at three bone union interfaces (two between the fibula and mandibular bones and one between the osteotomized fibulas) to investigate bone healing/remodeling events. Three-dimensional finite element models were created to quantify mechanobiological responses in the bone at these different time points. Bone mineral density increased rapidly along the bone interfaces over the first four months. Cortical bridging formed at the osteotomized interface earlier than the other two interfaces with larger shape discrepancy between fibula and mandibular bones. Bone morphology significantly affected mechanobiological responses in the osteotomized region (R2 > 0.77). The anatomic position and shape discrepancy at bone union affected the bone healing/remodeling process.

Inactivation of HMGCL promotes proliferation and metastasis of nasopharyngeal carcinoma by suppressing oxidative stress.

Altered metabolism is considered as a hallmark of cancer. Here we investigated expression of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) 2 lyase (HMGCL), an essential enzyme in ketogenesis, which produces ketone bodies by the breakdown of fatty acids to supply energy, in nasopharyngeal carcinoma (NPC). The expression of HMGCL was silenced in NPC tissue. Downregulation of HMGCL in NPC was associated with low intracellular ß-hydroxybutyrate (ß-HB) production, thereby reducing reactive oxygen species (ROS) generation. Ectopic expression of HMGCL restored ß-HB level, associated with suppressed proliferation and colony formation of NPC cells in vitro and decreased tumorigenicity in vivo. HMGCL suppressed the migration and invasion of NPC cells in vitro via mesenchymal-epithelial transition. Furthermore, extracellular ß-HB supply suppressed the proliferation and migration of NPC cells. Both intra- and extracellular ß-HB exerting a suppressive role in NPC depends on ROS generation. Ketogenesis may be impaired in NPC cells due to lack of HMGCL expression, suggesting that it may be a promising target in NPC therapy.

Glutaredoxin 3 promotes nasopharyngeal carcinoma growth and metastasis via EGFR/Akt pathway and independent of ROS.

Glutaredoxin 3 (GLRX3) is antioxidant enzyme, maintaining a low level of ROS, thus contributing to the survival and metastasis of several types of cancer. However, the expression and functions of GLRX3 have not been addressed in nasopharyngeal carcinoma (NPC). In this study, we found that GLRX3 was overexpressed in NPC. Knockdown of GLRX3 in NPC cell lines inhibited proliferation in vitro, tumorignesis in vivo, and colony formation. In addition, GLRX3 knockdown decreased the migration and invasion capacity of NPC cells by reversing the epithelial-mesenchymal transition (EMT). Furthermore, stabilization of GLRX3 was positively related to with epidermal growth factor receptor (EGFR) expression and negatively with ROS generation. Phosphorylation of Akt, a key downstream effector, was induced by EGFR signaling but did not rely on increasing ROS level in NPC cells. GLRX3 might be an oncoprotein in NPC, playing important roles in increasing redox reaction and activating EGFR/ Akt signals, so it may be a therapeutic target for NPC.