HOXA1 silencing inhibits cisplatin resistance of oral squamous cell carcinoma cells via IκB/NF-κB signaling pathway.

The resistance of oral squamous cell carcinoma (OSCC) cells to cisplatin remains a tough nut to crack in OSCC therapy. Homeobox A1 (HOXA1) overexpression has been detected in head and neck squamous carcinoma (HNSC). Accordingly, this study aims to explore the potential role and mechanism of HOXA1 on cisplatin resistance in OSCC. The expression of HOXA1 in HNSC and its role in overall survival (OS) rate of OSCC patients were analyzed by bioinformatic analysis. Following transfection as needed, OSCC cells were induced by different concentrations of cisplatin, and the cell viability and apoptosis were evaluated by cell counting kit-8 and flow cytometry assays. The mRNA and protein expression levels of HOXA1 and the phosphorylation of IκBα and p65 were determined by real-time quantitative PCR and western blot. HOXA1 expression level was upregulated in HNSC tissues and OSCC cells. Overexpressed HOXA1 was correlated with a low OS rate of OSCC patients. Cisplatin exerted an anti-cancer effect on OSCC cells. HOXA1 silencing or cisplatin suppressed OSCC cell viability, boosted the apoptosis, and repressed the phosphorylation of IκBα and p65. Intriguingly, the combination of HOXA1 silencing and cisplatin generated a stronger anti-cancer effect on OSCC cells than their single use. HOXA1 silencing attenuates cisplatin resistance of OSCC cells via IκB/NF-κB signaling pathway, hinting that HOXA1 is a biomarker associated with OSCC and HOXA1 silencing can enhance the sensitivity of OSCC cells to cisplatin.

Novel fusion protein PK5-RL-Gal-3C inhibits hepatocellular carcinoma via anti-angiogenesis and cytotoxicity.

BACKGROUND: Galectin-3 (Gal-3), the only chimeric ß-galactosides-binding lectin, consists of Gal-3N (N-terminal regulatory peptide) and Gal-3C (C-terminal carbohydrate-recognition domain). Interestingly, Gal-3C could specifically inhibit endogenous full-length Gal-3 to exhibit anti-tumor activity. Here, we aimed to further improve the anti-tumor activity of Gal-3C via developing novel fusion proteins. METHODS: PK5 (the fifth kringle domain of plasminogen) was introduced to the N-terminus of Gal-3C via rigid linker (RL) to generate novel fusion protein PK5-RL-Gal-3C. Then, we investigated the anti-tumor activity of PK5-RL-Gal-3C in vivo and in vitro by using several experiments, and figured out their molecular mechanisms in anti-angiogenesis and cytotoxicity to hepatocellular carcinoma (HCC). RESULTS: Our results show that PK5-RL-Gal-3C can inhibit HCC both in vivo and in vitro without obvious toxicity, and also significantly prolong the survival time of tumor-bearing mice. Mechanically, we find that PK5-RL-Gal-3C inhibits angiogenesis and show cytotoxicity to HCC. In detail, HUVEC-related and matrigel plug assays indicate that PK5-RL-Gal-3C plays an important role in inhibiting angiogenesis by regulating HIF1α/VEGF and Ang-2 both in vivo and in vitro. Moreover, PK5-RL-Gal-3C induces cell cycle arrest at G1 phase and apoptosis with inhibition of Cyclin D1, Cyclin D3, CDK4, and Bcl-2, but activation of p27, p21, caspase-3, -8 and -9. CONCLUSION: Novel fusion protein PK5-RL-Gal-3C is potent therapeutic agent by inhibiting tumor angiogenesis in HCC and potential antagonist of Gal-3, which provides new strategy for exploring novel antagonist of Gal-3 and promotes their application in clinical treatment.

Bifunctional Compounds as Molecular Degraders for Integrin-Facilitated Targeted Protein Degradation.

As effective ways to regulate protein levels, targeted protein degradation technologies have attracted great attention in recent years. Here, we established a novel integrin-facilitated lysosomal degradation (IFLD) strategy to degrade extracellular and cell membrane proteins using bifunctional compounds as molecular degraders. By conjugation of a target protein-binding ligand with an integrin-recognition ligand, the resulting molecular degrader proved to be highly efficient to induce the internalization and subsequent degradation of extracellular or cell membrane proteins in an integrin- and lysosome-dependent manner. As demonstrated in the development of BMS-L1-RGD, which is an efficient programmed death-ligand 1 (PD-L1) degrader validated both in vitro and in vivo, the IFLD strategy expands the toolbox for regulation of secreted and membrane-associated proteins and thus has great potential to be applied in chemical biology and drug discovery.

SNHG5/miR-582-5p/RUNX3 feedback loop regulates osteogenic differentiation and apoptosis of bone marrow mesenchymal stem cells.

Osteoporosis is one of the most prevailing orthopedic diseases that causes a heavy burden on public health. Given that bone marrow-derived mesenchymal stem cells (BMSCs) are of immense importance in osteoporosis development, it is necessary to expound the mechanisms underlying BMSC osteoblastic differentiation. Although mounting research works have investigated the role of small nucleolar RNA host gene 5 (SNHG5) in various diseases, elucidations on its function in osteoporosis are still scarce. It was observed that SNHG5 and RUNX family transcription factor 3 (RUNX3) were remarkably elevated during osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). Further, we disclosed that the silencing of SNHG5 suppressed osteogenic differentiation and induced apoptosis of hBMSCs. What's more, SNHG5 acted as a competing endogenous RNA to affect RUNX3 expression via competitively binding with microRNA (miR)-582-5p. RUNX3 was also confirmed to simulate the transcriptional activation of SNHG5. Finally, our findings manifested that the positive feedback loop of SNHG5/miR-582-5p/RUNX3 executed the promoting role in the development of osteoporosis, which shed light on specific molecular mechanism governing SNHG5 in osteogenic differentiation and apoptosis of hBMSCs and indicated that SNHG5 may represent a novel target for the improvement of osteoporosis therapy.

Silencing RhoA inhibits migration and invasion through Wnt/ß-catenin pathway and growth through cell cycle regulation in human tongue cancer.

Ras homolog gene family member A (RhoA) has been identified as a critical regulator of tumor aggressive behavior. In this study, we assessed the role of RhoA in the mechanisms underlying growth, migration, and invasion of squamous cell carcinoma of tongue (TSCC). Stable RhoA knockdown of TSCC cell lines SCC-4 and CAL27 were achieved using Lentiviral transfection. The effects of RhoA depletion on cell migration, invasion, and cell proliferation were determined. The possible underlying mechanism of RhoA depletion on TSCC cell line was also evaluated by determining the expression of Galectin-3 (Gal-3), ß-catenin, and matrix metalloproteinase-9 (MMP-9) in vivo. Meanwhile, the underlying mechanism of TSCC growth was studied by analysis of cyclin D1/2, p21CIP1/WAF1, and p27Kip1 protein levels. Immunohistochemical assessments were performed to further prove the alteration of Gal-3 and ß-catenin expression. We found that, in mice injected with human TSCC cells in the tongue, RhoA levels were higher in primary tumors and metastasized lymph nodes compared with those in the normal tissues. Silencing of RhoA significantly reduced the tumor growth, decreased the levels of Gal-3, ß-catenin, MMP-9, and cyclin D1/2, and increased the levels of p21CIP1/WAF1 and p27Kip1. In vitro, RhoA knockdown also led to inhibition of cell migration, invasion, and proliferation. Our data suggest that RhoA plays a significant role in TSCC progression by regulating cell migration and invasion through Wnt/ß-catenin signaling pathway and cell proliferation through cell cycle regulation, respectively. RhoA might be a novel therapeutic target of TSCC.

SENP1 inhibits ferroptosis and promotes head and neck squamous cell carcinoma by regulating ACSL4 protein stability via SUMO1.

Head and neck squamous cell carcinoma (HNSCC) is currently one of the most common malignancies with a poor prognosis worldwide. Meanwhile, small ubiquitin­like modifier (SUMO) specific peptidase 1 (SENP1) was associated with ferroptosis. However, the specific functions and underlying mechanisms of action of SENP1 in ferroptosis and tumor progression of HNSCC remain to be established. The findings of the present study implicated a novel ferroptosis pathway in the initiation and progression of HNSCC, providing new functional targets to guide future therapy. In the present study, The Cancer Genome Atlas database was employed to establish a gene model related to ferroptosis and verified SENP1 as a key gene via transcriptome sequencing. Expression of SENP1 in HNSCC tissue and CAL­27 cells was detected based on reverse transcription­quantitative PCR and western blot analysis. Proliferation and migration abilities of cells were determined using Cell Counting Kit­8, wound healing and Transwell experiments. Expression levels of iron, glutathione (GSH) and lipid peroxidation end­product malondialdehyde (MDA) under conditions of silencing of SENP1 with shRNA lentivirus were assayed. Additionally, the relationship between SENP1 and long­chain acyl­coenzyme A synthase 4 (ACSL4) was validated with the aid of immunoblotting and co­immunoprecipitation (co­IP). Finally, the influence of shSENP1 on the expression of key ferroptosis proteins, glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11, was evaluated via western blotting. It was revealed that SENP1 was significantly overexpressed in HNSCC and associated with low patient survival. Silencing of SENP1 led to significant suppression of cell proliferation, migration and invasion, increase in the contents of iron ions and MDA and decline in GSH levels in HNSCC cells, thereby enhancing ferroptosis and inhibiting disease progression. Conversely, overexpression of SENP1 suppressed ferroptosis and promoted progression of HNSCC. Co­IP and western blot analyses revealed a SUMOylation link between SENP1 and ACSL4. SENP1 reduced the stability of ACSL4 protein through deSUMOylation, leading to inhibition of ferroptosis. SENP1 silencing further inhibited the expression of the key iron death protein, GPX4, to regulate ferroptosis. Taken together, SENP1 deficiency promoted ferroptosis and inhibited tumor progression through reduction of SUMOylation of ACSL4 in HNSCC. The collective results of the present study supported the utility of SENP1 as an effective predictive biomarker for targeted treatment of HNSCC.

Polyethylenimine Triggers Dll4 Degradation to Regulate Angiogenesis In Vitro.

The Dll4-Notch signaling pathway plays a crucial role in the regulation of angiogenesis and is a promising therapeutic target for diseases associated with abnormal angiogenesis, such as cancer and ophthalmic diseases. Here, we find that polyethylenimine (PEI), a cationic polymer widely used as nucleic acid transfection reagents, can target the Notch ligand Dll4. By immunostaining and immunoblotting, we demonstrate that PEI significantly induces the clearance of cell-surface Dll4 and facilitates its degradation through the lysosomal pathway. As a result, the activation of Notch signaling in endothelial cells is effectively inhibited by PEI, as evidenced by the observed decrease in the generation of the activated form of Notch and expression of Notch target genes Hes1 and Hey1. Furthermore, through blocking Dll4-mediated Notch signaling, PEI treatment enhances angiogenesis in vitro. Together, our study reveals a novel biological effect of PEI and establishes a foundation for the development of a Dll4-targeted biomaterial for the treatment of angiogenesis-related disease.

Signalling pathways in the osteogenic differentiation of periodontal ligament stem cells.

Periodontal ligament stem cells (PDLSCs) have multidirectional differentiation potential and self-renewal abilities and are important seed cells for the regenerative repair of periodontal tissues. In recent years, many studies have identified multiple signalling pathways involved in regulating the osteogenic differentiation of PDLSCs in an inflammatory environment. In this article, we review the osteogenic differentiation of PDLSCs in an inflammatory environment in terms of signalling pathways and provide new ideas for the regenerative treatment of periodontal tissues.

Metallodrugs in the battle against non-small cell lung cancer: unlocking the potential for improved therapeutic outcomes.

Non-small cell lung cancer (NSCLC) remains a leading cause of cancer mortality worldwide. Platinum-based chemotherapy is standard-of-care but has limitations including toxicity and resistance. Metal complexes of gold, ruthenium, and other metals have emerged as promising alternatives. This review provides a comprehensive analysis of metallodrugs for NSCLC. Bibliometric analysis reveals growing interest in elucidating mechanisms, developing targeted therapies, and synergistic combinations. Classification of metallodrugs highlights platinum, gold, and ruthenium compounds, as well as emerging metals. Diverse mechanisms include DNA damage, redox modulation, and immunomodulation. Preclinical studies demonstrate cytotoxicity and antitumor effects in vitro and in vivo, providing proof-of-concept. Clinical trials indicate platinums have utility but resistance remains problematic. Non-platinum metallodrugs exhibit favorable safety but modest single agent efficacy to date. Drug delivery approaches like nanoparticles show potential to enhance therapeutic index. Future directions include optimization of metal-based complexes, elucidation of resistance mechanisms, biomarker development, and combination therapies to fully realize the promise of metallodrugs for NSCLC.

[Changes and significance of serum prealbumin expression in patients with oral and maxillofacial space infections].

PURPOSE: To investigate the changes of serum prealbumin (PA) expression level in patients with oral and maxillofacial space infections and its significance. METHODS: Patients hospitalized at the Affiliated Hospital of Xuzhou Medical University from January 2020 to September 2021 were selected and divided into infected and non-infected group. One hundred and twenty-one patients with moderate to severe oral and maxillofacial gap infections were in the infected group, and 128 patients without infection were in the non-infected group. In the infected group, PA, high-sensitivity C-reactive protein (hs-CRP) and white blood cell count (WBC) levels and related clinical parameters were measured at 1, 3 and 7 d of admission. In the non-infected group, PA, hs-CRP and WBC levels were measured at 1 d of admission. SPSS 23.0 software package was used to statistically analyze the relationship between PA levels and various laboratory and clinical parameters. RESULTS: PA levels in the infected group were significantly lower than those in the non-infected group at 1 d of admission. PA levels in the infected group showed an overall increasing trend at different time points, and PA was negatively correlated with pain intensity and positively correlated with mouth opening(P＜0.05). The diagnostic sensitivity was 90.91% and the specificity was 92.97% for PA≤19.85 mg/dL, which can be used as the best diagnostic threshold. The diagnostic efficacy can be improved when combined with hs-CRP and WBC. Logistic regression analysis showed that low PA level was an independent risk factor for patients requiring intensive care after surgery (P＜0.05). CONCLUSIONS: PA is an effective tool for the early diagnosis and evaluation of the efficacy of oral and maxillofacial interstitial infections, and can be used as a reference indicator to assess prognosis.

Synthetic role of miR-200b-3p, ABCD2 score, and carotid ultrasound in the prediction of cerebral infarction in patients with transient ischemic attack.

BACKGROUND: Transient ischemic attack (TIA) is a major risk factor for the occurrence of cerebral infarction (CI). This study aimed to evaluate the predictive value of the synthetic role of miR-200b-3p, ABCD2 score, and carotid ultrasound for CI onset in patients with TIA. METHODS: Expression of miR-200b-3p was detected by reverse transcription quantitative PCR and carotid stenosis degree was evaluated using carotid ultrasound examination. Association of miR-200b-3p with ABCD2 scores and carotid stenosis degree was assessed using t-test and chi-square test. Logistic regression analysis was used to judge the ability of miR-200b-3p, ABCD2 score, and carotid ultrasound to predict the occurrence of CI. Receiver operating characteristic curve was used to analyze the diagnostic value of miR-200b-3p and the accuracy of miR-200b-3p, ABCD2 score, and carotid ultrasound in predicting CI development. RESULTS: Expression of serum miR-200b-3p was significantly increased in TIA patients compared with healthy controls, and had diagnostic value in TIA patients. Serum miR-200b-3p was significantly associated with dyslipidemia, ABCD2 score, and carotid stenosis degree in TIA patients. ABCD2 score, carotid stenosis degree, and serum miR-200b-3p were independently associated with CI onset, and the synthetic role of these three indicators had the best accuracy in the prediction of CI onset in TIA patients. CONCLUSION: Serum miR-200b-3p expression was increased in TIA patients with considerable diagnostic value to screen TIA cases from healthy controls. Moreover, we speculated that the combination of miR-200b-3p, ABCD2 score, and carotid stenosis degree by ultrasound may propose as an efficient predictive strategy for the prediction of CI in TIA patients.

Osteogenic differentiation of periodontal membrane stem cells in inflammatory environments.

Periodontitis is a common disease that is difficult to treat, and if not controlled in time, it causes severe conditions, such as alveolar bone resorption and tooth loosening and loss. Periodontal ligament stem cells constitute a promising cell source for regenerative treatment of periodontitis due to their high osteogenic differentiation capacity. PDLSC osteogenesis plays a central role in periodontal regeneration through successive cytokine-mediated signaling pathways and various biochemical and physicochemical factors. However, this process is inhibited in the inflammatory periodontitis environment due to high concentrations of lipopolysaccharide. Here, we review the mechanisms that influence the osteogenic differentiation of periodontal stem cells in this inflammatory microenvironment.

The whole-genome assembly of an endangered Salicaceae species: Chosenia arbutifolia (Pall.) A. Skv.

BACKGROUND: As a fast-growing tree species, Chosenia arbutifolia has a unique but controversial taxonomic status in the family Salicaceae. Despite its importance as an industrial material, in ecological protection, and in landscaping, C. arbutifolia is seriously endangered in Northeast China because of artificial destruction and its low reproductive capability. RESULTS: To clarify its phylogenetic relationships with other Salicaceae species, we assembled a high-quality chromosome-level genome of C. arbutifolia using PacBio High-Fidelity reads and Hi-C sequencing data, with a total size of 338.93 Mb and contig N50 of 1.68 Mb. Repetitive sequences, which accounted for 42.34% of the assembly length, were identified. In total, 33,229 protein-coding genes and 11,474 small noncoding RNAs were predicted. Phylogenetic analysis suggested that C. arbutifolia and poplars diverged approximately 15.3 million years ago, and a large interchromosomal recombination between C. arbutifolia and other Salicaceae species was discovered. CONCLUSIONS: Our study provides insights into the genome architecture and systematic evolution of C. arbutifolia, as well as comprehensive information for germplasm protection and future functional genomic studies.

Complete chloroplast genome sequencing of five Salix species and its application in the phylogeny and taxonomy of the genus.

In this study, whole chloroplast genomes of five Salix species (S. argyracea, S. dasyclados, S. eriocephala, S. integra 'Hakuro Nishiki', and S. suchowensis) were sequenced. These chloroplast genomes were 155 ,605, 155, 763, 155, 552, 155, 538, and 155 ,550 bp in length, harboring 131 genes (77 unigenes), 37 tRNA genes, 8 rRNA genes, and 86 mRNA genes, respectively. The genes ycf1, psaI, ycf2-2, rpoC2, rpl22, atpF, and ndhF were under positive selection among the 21 Salix species. psaI, ycf2-2, atpF, and ycf1-2 were under positive selection between the tree willow and shrub willow, and rpoC2, rpl22, and ycf1-2 were positively selected among the shrub genomes. The gene rps7 was most variable among the genomes. Phylogenetic analysis of 21 Salix species and Chosenia arbutifolia provide evidence that the cp genome data partially support the relationship with traditional taxonomic concepts in the Flora of China. This chloroplast genome elucidates Salix taxonomy and provides evidence for evolutionary research.

Efficient synthesis of niobium pentoxide nanowires and application in ethanolysis of furfuryl alcohol.

Nb2O5 nanowires with high specific surface area and crystallinity were prepared by using ammonium oxalate and an acetic acid solvent system. The nanomaterial was applied in ethanolysis of furfuryl alcohol (FA), and the yield of the product, 2-(ethoxymethyl)furan (FEE), achieved was up to 79.6%. Compared to mesoporous Nb2O5 materials and other porous materials, the residence time of FEE on the surface of the catalyst is shorter, and the yield of ethyl levulinate (EL) is lower. Furthermore, a high temperature calcination treatment can change the acid sites and acidity type distribution on the nanowire surface. By XRD, NH3-TPD, IR, and TG-DTA determination methods, it was found that the weak and medium-strong acid sites on the surface of Nb2O5 nanowires were reduced after a 300 °C treatment, and the amount of strong acid was relatively higher. According to the catalytic performance test data and acidity determination, it was concluded that more weak acid and medium-strong acid sites improve the conversion of furfuryl alcohol to FEE, and the strong acid sites promote further conversion of FEE to EL.

Anti-malarial atovaquone exhibits anti-tumor effects by inducing DNA damage in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, and is the third most frequent cause of cancer-related deaths worldwide. The development of safe new anti-tumor agents has become increasingly important due to the steady rise in drug-resistant tumors. After assessing the efficacy of several candidate compounds that could inhibit hepatocellular carcinoma, we focused on atovaquone, an FDA-approved anti-malarial drug. In the present study, we found that atovaquone significantly inhibited hepatoma cell proliferation via S phase cell cycle arrest and both extrinsic and intrinsic apoptotic pathway induction associated with upregulation of p53 and p21. Molecular investigations demonstrated that atovaquone inhibits hepatoma cell proliferation by inducing double-stranded DNA breaks, leading to sustained activation of ataxia-telangiectasia mutated (ATM) and its downstream molecules such as cell cycle checkpoint kinase-2 (CHK2) and H2AX. In addition, we found that atovaquone also induced apoptosis, inhibited both cell proliferation and angiogenesis in vivo, and prolonged the survival time of tumor-bearing mice, without any obvious side effects. In conclusion, our data indicate that atovaquone is a safe and effective candidate drug that could be rapidly repurposed for HCC treatment.

Effect of simvastatin and microRNA-21 inhibitor on metastasis and progression of human salivary adenoid cystic carcinoma.

Salivary adenoid cystic carcinoma (SACC) is a common malignancy of the salivary glands. Epithelial-mesenchymal transition (EMT) and P53 signaling pathway are associated with SACC metastasis and progression. Although simvastatin (SIM) is effective against the growth of many cancer types, its side effects limit its use. microRNA-21 (miR-21) is highly expressed in a variety of tumors and has a role in promoting tumor development. Therefore, the aim of the present study was to evaluate the effect of SIM in combination with miR-21 inhibitor (miR-21i) against lung metastatic SACC cells (SACC-LM). Our results showed that miR-21i was effective in reducing the resistance of SACC-LM to SIM, resulting in SACC-LM acquisition of epithelial traits, cell migration and invasion reduction, growth inhibition and induction of apoptosis. The expression of proteins associated to metastasis and tumor progression were regulated by the combined use of SIM and miR-21i. Thus, our findings demonstrated that such combination was effective in inhibiting SACC-LM progression, suggesting that multi-target therapy against SACC might represent a potentially successful approach in clinical treatment.

Propofol inhibits Wnt signaling and exerts anticancer activity in glioma cells.

Aberrant activation of Wnt signaling is implicated in gliomagenesis. Propofol, the most commonly used intravenous anesthetic agent in clinics, exhibits potent antitumor activity in a variety of cancer cells through different mechanisms. However, the role of propofol on Wnt signaling and glioma cell growth remains to be fully elucidated. In the present study, propofol was identified as a potent inhibitor of Wnt signaling. In 293T cells transfected with Wnt1 or Wnt3 expression plasmids or treated with Wnt3A-conditioned medium, propofol significantly inhibited the transcriptional activity of the SuperTopFlash reporter and the expression of Wnt target genes. The inhibitory effect of propofol on Wnt signaling was also observed in glioma cells. Further experiments demonstrated that propofol suppressed glioma cell growth by decreasing cell proliferation and enhancing cell apoptosis. Finally, the potential antitumor efficiency of propofol was confirmed using xenograft experiments in vivo. Taken together, the results indicated a novel mechanism for the anticancer activity of propofol and provide supporting evidence for its use as a prospective anticancer drug to treat glioma in patients with deregulated Wnt signaling.

[A retrospective study on incisor root resorption in patients treated with bracketless invisible appliance and straight wire appliance].

PURPOSE: To assess root resorptions in patients treated with bracketless invisible appliance and straight wire appliance using cone-beam CT (CBCT). METHODS: Twenty-eight patients treated with bracketless invisible appliance (as experimental group) or straight wire appliance (as control group) were randomly selected. CBCT images were analyzed at 3 time points (pre-operation, 6 month after operation, post-operation). Root resorption was calculated using root length at 3 time points. The difference between the 2 groups was analyzed with SPSS16.0 software package. To those teeth with no root length reduction, the bone defect was evaluated using CBCT. RESULTS: After 6-month of treatment, 47.3% teeth from the experimental group had root resorption, while 68.3% in the control group. There was significant difference between the 2 groups (P<0.05). Root absorption of maxillary central incisors from the 2 groups was more severe than other teeth (55% in the experimental group, and 75% in the control group). After orthodontic treatment, the incidence of root resorption in the control groups increased to be 85.3% and 68.3% in the experimental group (P<0.05). To those teeth with no root resorption, bone defect was more common in the palatal side (18% in the experimental group, 14% in the control group). CONCLUSIONS: Compared with straight wire appliance, patients using bracketless invisible appliance suffer from less root resorption.