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Renal fibrosis, a progressive scarring of the kidney, lacks effective treatment. Human umbilical cord mesenchymal stem cell-derived exosomes (HucMSC-Exos) hold promise for treating kidney diseases due to their anti-inflammatory properties. This study investigates their potential to lessen renal fibrosis by targeting macrophage-to-myofibroblast transformation (MMT), a key driver of fibrosis. We employed a mouse model of unilateral ureteral obstruction (UUO) and cultured cells exposed to transforming growth factor-ß (TGF-ß) to mimic MMT. HucMSC-Exos were administered to UUO mice, and their effects on kidney function and fibrosis were assessed. Additionally, RNA sequencing and cellular analysis were performed to elucidate the mechanisms by which HucMSC-Exos inhibit MMT. HucMSC-Exos treatment significantly reduced kidney damage and fibrosis in UUO mice. They downregulated markers of fibrosis (Collagen I, vimentin, alpha-smooth muscle actin) and suppressed MMT (α-SMA + F4/80 + cells). Furthermore, ARNTL, a specific molecule, emerged as a potential target of HucMSC-Exos in hindering MMT and consequently preventing fibrosis. HucMSC-Exos effectively lessen renal fibrosis by suppressing MMT, suggesting a novel therapeutic strategy for managing kidney damage and fibrosis.
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PURPOSE: We investigated the efficacy and safety of high-dose vitamin D supplementation (VDS) plus standard urotherapy (SU) in managing overactive bladder dry in children. MATERIALS AND METHODS: A 3-arm, randomized clinical trial was performed at an academic center in China between January 2023 and June 2023. Eligible patients (n=303) were randomized to receive 8 weeks of high-dose VDS (vitamin D3 drops encapsulated as soft capsules, 2400 IU/d) plus SU (VDS + SU group; n=100), solifenacin (5-10 mg/d) plus SU (SOL + SU group; n=102), or SU alone (SU group; n=101). Reduction in voiding frequency was the primary outcome. Secondary outcomes encompassed improvement in urgency, nocturia, quality of life score, pediatric lower urinary tract symptom score, and participant satisfaction. Treatment-emergent adverse events were recorded within each group. RESULTS: Participants had a median age of 82.0 months and their baseline mean vitamin D level was 22.64 ng/mL. The VDS + SU group showed greater improvements in voids/d than the SOL + SU group (median difference 3.0; 95% CI, 2.0 to 3.5; P < .001) and the SU group (median difference 4.0; 95% CI, 3.0 to 5.0; P < .001) after intervention. The VDS + SU group also showed the greatest improvement in quality of life and pediatric lower urinary tract symptom scores. Patient satisfaction was similar between the SOL + SU and SU groups. The VDS + SU group did not exhibit a heightened risk of treatment-emergent adverse events compared to the other groups. CONCLUSIONS: High-dose VDS plus SU was effective and well-tolerated in managing overactive bladder dry in children, suggesting its potential as a novel therapeutic option for this population.
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Succinato de Solifenacina , Vejiga Urinaria Hiperactiva , Niño , Humanos , Suplementos Dietéticos , Antagonistas Muscarínicos , Calidad de Vida , Resultado del Tratamiento , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vitamina D/uso terapéuticoRESUMEN
Alveolar rhabdomyosarcoma (ARMS) is a rare but highly aggressive cancer predominantly affecting children and adolescents. This study explores prognostic factors for pediatric and adolescent ARMS, using the Surveillance, Epidemiology, and End Results (SEER) database. Leveraging SEER data (2000-2019), we analyzed 277 cases. Employing Kaplan-Meier survival analysis and Cox proportional hazards models, we identified significant prognostic factors. Gender distribution was nearly equal (56.0% boys, 44.0% girls), with the majority (70.8%) from the white ethnic group. Primary tumors were predominantly in extremities (37.2%). Distant metastases significantly increased mortality risk (hazard ratio [HR], 3.13; 95% CI: 2.14-4.58) and regional lymph node involvement raised mortality risk (HR, 1.36; 95% CI: 0.96-1.92). Chemotherapy-only treatment had higher mortality risk than chemoradiotherapy (HR, 1.16; 95% CI: 0.97-2.67). Conclusively, our study identifies distant metastases, regional lymph node involvement, and treatment modality as crucial predictors of overall survival in pediatric ARMS.
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Purpose: Develop and validate an accessible prediction model using machine learning (ML) to predict the risk of chemotherapy-induced myelosuppression (CIM) in children with Wilms' tumor (WT) before chemotherapy is administered, enabling early preventive management. Methods: A total of 1433 chemotherapy cycles in 437 children with WT who received chemotherapy in our hospital from January 2009 to March 2022 were retrospectively analyzed. Demographic data, clinicopathological characteristics, hematology and blood biochemistry baseline results, and medication information were collected. Six ML algorithms were used to construct prediction models, and the predictive efficacy of these models was evaluated to select the best model to predict the risk of grade ≥ 2 CIM in children with WT. A series of methods, such as the area under the receiver operating characteristic curve (AUROC), the calibration curve, and the decision curve analysis (DCA) were used to test the model's accuracy, discrimination, and clinical practicability. Results: Grade ≥ 2 CIM occurred in 58.5% (839/1433) of chemotherapy cycles. Based on the results of the training and validation cohorts, we finally identified that the extreme gradient boosting (XGB) model has the best predictive efficiency and stability, with an AUROC of up to 0.981 in the training set and up to 0.896 in the test set. In addition, the calibration curve and the DCA showed that the XGB model had the best discrimination and clinical practicability. The variables were ranked according to the feature importance, and the five variables contributing the most to the model were hemoglobin (Hgb), white blood cell count (WBC), alkaline phosphatase, coadministration of highly toxic chemotherapy drugs, and albumin. Conclusions: The incidence of grade ≥ 2 CIM was not low in children with WT, which needs attention. The XGB model was developed to predict the risk of grade ≥ 2 CIM in children with WT for the first time. The model has good predictive performance and stability and has the potential to be translated into clinical applications. Based on this modeling and application approach, the extension of CIM prediction models to other pediatric malignancies could be expected.
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BACKGROUND: Kidney insults due to various pathogenic factors, such as trauma, infection, and inflammation, can cause tubular epithelial cell injury and death, leading to acute kidney injury and the transformation of acute kidney injury to chronic kidney disease. There is no definitive treatment available. In previous studies, human umbilical cord mesenchymal stem cells have been shown to promote kidney injury. In this preclinical study, we investigate the role and mechanism of human umbilical cord mesenchymal stem cell exosomes (HucMSC-Exos) on the repair of renal tubular epithelial cells after injury. METHODS: C57BL/6 mice underwent unilateral ureteral obstruction, and epithelial cell injury was induced in HK-2 cells by cisplatin. HucMSC-Exos were assessed in vivo and in vitro. The extent of renal cell injury, activation of necroptosis pathway, and mitochondrial quality-control-related factors were determined in different groups. We also analyzed the possible regulatory effector molecules in HucMSC-Exos by transcriptomics. RESULTS: HucMSC-Exo inhibited necroptosis after renal tubular epithelial cell injury and promoted the dephosphorylation of the S637 site of the Drp1 gene by reducing the expression of PGAM5. This subsequently inhibited mitochondrial fission and maintained mitochondrial functional homeostasis, mitigating renal injury and promoting repair. In addition, HucMSC-Exo displayed a regulatory role by targeting RIPK1 through miR-874-3p. CONCLUSION: The collective findings of the present study demonstrate that HucMSC-Exos can regulate necroptosis through miR-874-3p to attenuate renal tubular epithelial cell injury and enhance repair, providing new therapeutic modalities and ideas for the treatment of AKI and the process of AKI to CKD transformation to mitigate renal damage.
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Lesión Renal Aguda , Exosomas , Células Madre Mesenquimatosas , MicroARNs , Ratones , Animales , Humanos , Exosomas/metabolismo , Ratones Endogámicos C57BL , MicroARNs/genética , Riñón/metabolismo , Cordón Umbilical , Lesión Renal Aguda/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Epiteliales/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Mitocondriales/metabolismoRESUMEN
Renal fibrosis is a common pathological feature of various kidney diseases, leading to irreversible renal failure and end-stage renal disease. However, there are still no effective treatments to reverse renal fibrosis. This study aimed to explore the potential mechanism of a targeted drug for fibrosis. Here, unilateral ureteral obstruction (UUO)-treated mice and a TGF-ß1-treated human renal tubular epithelial cell line (HK-2 cells) were used as models of renal fibrosis. Based on the changes of mRNA in UUO kidneys detected by transcriptome sequencing, MK-2206, an Akt inhibitor, was predicted as a potential drug to alleviate renal fibrosis through bioinformatics. We dissolved UUO mice with MK-2206 by gastric gavage and cultured TGF-ß-induced HK-2 cells with MK-2206. Histopathological examinations were performed after MK-2206 intervention, and the degree of renal fibrosis, as well as the expression of Akt/mTOR pathway-related proteins, were evaluated by immunohistochemical staining, immunofluorescence staining, and Western blot. The results showed that MK-2206 significantly improved the pathological structure of the kidney. Furthermore, MK-2206 intervention effectively inhibited UUO- and TGF-ß1-induced epithelial-mesenchymal transition, fibroblast activation, and extracellular matrix deposition. Mechanistically, MK-2206 treatment attenuated the activation of the Akt/mTOR signaling pathway. Taken together, our study revealed for the first time that MK-2206 is a promising drug for the improvement of renal fibrosis.
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Enfermedades Renales , Obstrucción Ureteral , Ratones , Humanos , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fibrosis , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/metabolismo , Transducción de Señal , Obstrucción Ureteral/tratamiento farmacológico , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
BACKGROUND: The Non-Small Cell Variant of Lung Cancer (NSCLC) has a poorer prognosis. It is typically diagnosed through non-invasive imaging. Of particular note has been FDGPET/ CT, which has been investigated across various settings with differing results. OBJECTIVE: This study is to pool the available information on the diagnostic performance of 18-F FDG PET/CT for detecting NSCLC recurrence. METHODS: A systematic literature search was conducted across electronic databases for studies published before May 2021. The QUADAS tool was applied to assess study quality, and a metaanalysis was performed to retrieve pooled estimates. Chi-squared tests and I2 statistics were used to assess heterogeneity. Egger's test and funnel plots were used to assess publication bias. RESULTS: The literature search yielded 20 studies featuring data on 1,973 patients. The majority of the studies had a low bias risk. The pooled sensitivity and specificity were 96% (95% CI: 91%- 98%) and 93% (95% CI: 89%-95%), respectively. The LRP and LRN estimates were in the left upper quadrant of the LR scattergram, indicating that F18-FDG PET/CT can be utilized for both confirmation and exclusion. The AUC was 0.98 (95% CI: 0.92-0.99). Fagan's nomogram showed that F18-FDG PET/CT had good clinical utility for recurrent NSCLC diagnosis. There was considerable between-study variability (p=0.02). The funnel plot was asymmetrical, indicating the possibility of publication bias. CONCLUSION: This meta-analysis found FDG-PET/CT to be highly accurate for identifying NSCLC recurrence. However, more studies assessing this modality across different patient situations are required to strengthen the argument for changing international guidelines and practices.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Radiofármacos , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Tomografía de Emisión de Positrones/métodosRESUMEN
Cryptorchidism-caused adult infertility is a common component of idiopathic reasons for male infertility. Retinoic acid (RA) has a vital effect on the spermatogenesis process. Here, we found that the expression of c-Kit, Stra8, and Sycp3 could be up-regulated via the activation of retinoic acid receptor α (RARα) after RA supplementation in neonatal cryptorchid infertile rats. We also demonstrated that the protein expression of PI3K, p-Akt/pan-Akt, and p-mTOR/mTOR was higher in cryptorchid than in normal testes, and could be suppressed with RA in vivo. After RA treatment in infertile cryptorchid testis in vivo, the levels of the autophagy proteins LC3 and Beclin1 increased and those of P62 decreased. Biotin tracer indicated that the permeability of blood-testis barrier (BTB) in cryptorchid rats decreased after RA administration. Additionally, after blocking the RARα with AR7 (an RARα antagonist) in testicle culture in vitro, we observed that compared with normal testes, the PI3K-Akt-mTOR signaling pathway and the autophagy pathway was increased and decreased, respectively, which were coincident with cryptorchisd testes in vivo. Additionally, the appropriate concentrations of RA treatment could depress the PI3K-Akt-mTOR signaling pathway and improve the autophagy pathway. The results confirmed that RA can rehabilitate BTB function and drive key protein levels in spermatogonial differentiation through depressing the PI3K-Akt-mTOR signaling pathway via RARα.
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In order to systematically study the nanopermeability properties of saturated soft clay under different consolidation pressures and different osmotic pressures, this paper analyzes various loading and unloading conditions that affect the permeability of soil based on the material description equation with displacement as the control variable of large deformation consolidation theory. By summarizing the empirical relationship between permeability coefficient and consolidation pressure and permeability coefficient and void ratio, the infiltration law and seepage failure characteristics of soft clay are revealed. For the soil studied in this paper, a = 0.65, b = 0.001, and q = 3.55 are acceptable. The effect of the initial permeability coefficient on large deformation consolidation is studied, and the necessity and plausibility of considering the nonlinearity of the compression and permeability coefficient when calculating the soft-land base large deformation consolidation is also studied.
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BACKGROUND: Despite the continuous development and evolution of surgical methods and techniques, proximal hypospadias remains one of the most challenging issues for pediatric urologists. This study aims to evaluate the indications and postoperative complications of our new modified Duckett urethroplasty. METHODS: A total of 133 patients with proximal hypospadias who underwent repair of the modified Duckett urethroplasty from February 2016 to February 2021 were reviewed. The median age of patients was 3 years (range 1-16). All patients had severe chordee. One senior experienced pediatric urologist performed all the surgeries. Catheter was removed 14 days after the surgery. RESULTS: The location of the urethral meatus was proximal penile in 26 patients (19.5%), penoscrotal in 60 (45.1%), scrotal in 31 (23.3%), and perineal in 16 (12.0%). The mean length of the urethral defect was 4.5 cm (range 2.5-10). The median duration of follow-up was 46 months (range 8-67). Complications occurred in 31 patients (23.3%), including urethra-cutaneous fistula in 22 (16.5%), urethral stenosis in 7 (5.3%), and urethral diverticulum in 2 (1.5%). No recurrent chordee were found in all cases. All patients who developed complications were treated successfully at our hospital. CONCLUSIONS: Our modified Duckett urethroplasty showed functionally and cosmetically favorable outcomes, with a lower incidence of postoperative complications. To the best of our knowledge, the novel Duckett technique is a feasible and suitable option for patients who suffer from proximal hypospadias with severe chordee and dysplasia of the urethral plate.
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Hipospadias , Estrechez Uretral , Adolescente , Niño , Preescolar , Humanos , Hipospadias/etiología , Hipospadias/cirugía , Lactante , Masculino , Pene/cirugía , Uretra/cirugía , Estrechez Uretral/cirugía , Procedimientos Quirúrgicos Urológicos Masculinos/métodosRESUMEN
Bacteria, especially gut bacteria play important roles in human health and diseases. The classification of many bacterial genera by the 16S ribosomal RNA (rRNA) has failed due to its low inter-species resolution. Given the wide distribution of riboswitches in bacteria, they may help 16S rRNA differentiate closely related species. We found that among 28 groups of species that could not be distinguished by 16S rRNA, eight of them could be separated by the TPP riboswitch and other riboswitches. Moreover, the species in the 16S rRNA database and these riboswitch databases overlap, therefore, using riboswitch databases can help 16S rRNA better identify species. In addition, we used Klenow DNA polymerase and a pair of short primers to facilitate the library construction of TPP riboswitches for sequencing. The sequencing results showed that the TPP riboswitch could detect the major phyla similar to those detected by 16S rRNA. Therefore, the TPP riboswitch and other riboswitch classes could potentially be applied to gut bacteria classification.
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Microbioma Gastrointestinal , Riboswitch , Bacterias/genética , Microbioma Gastrointestinal/genética , Humanos , Filogenia , ARN Ribosómico 16S/genética , Riboswitch/genéticaRESUMEN
Purpose: Pediatric testicular yolk sac tumor is a rare malignant germ cell tumor and there is a lack of large clinical studies. The purpose of this study is to summarize the clinical characteristics of pediatric testicular yolk tumor and evaluate the prognostic factors. Materials and methods: The medical records of children with testicular yolk sac tumor in one pediatric medical centre in China from January 2005 to January 2021 were retrospectively investigated. Data regarding clinical characteristics, treatment and prognosis were collected. Results: A total of 109 patients with a median diagnosed age of 18 months (range 2-69) were included in this study; of them 100 were diagnosed as stage I, 6 as stage II and 3 as stage IV. All patients underwent radical orchiectomy, and 61 of them underwent postoperative chemotherapy. The mean follow-up time was 61.3 months (range 3-259), during that time, 8 patients experienced relapse. The five-year overall survival was 90.6% (95% CI 84.6%-96.7%). Univariate Cox regression analysis showed that disease stage, relapse, maximum tumor diameter, and alpha-fetoprotein returning to normal within 2 months postoperatively were risk factors for survival (HRs of 25.43, 26.43, 1.48 and 0.08, respectively, p < 0.05). Multivariate Cox regression analysis suggested that higher disease stage and relapse were independent adverse factors for survival (HRs of 148.30 and 94.58, respectively, p < 0.05). Conclusions: The prognosis of pediatric testicular yolk sac tumor is generally excellent. A higher disease stage and the occurrence of relapse could predict a poor prognosis. The individualized management of children with testicular yolk sac tumor according to risk classification is feasible.
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We describe and summarize the diagnosis, treatment, and reasons for delayed treatment of children with cryptorchidism torsion in Children's Hospital of Chongqing Medical University. The study included 19 cases of cryptorchidism torsion. The age of the children ranged from 16 days to 12 years (median: 6 years). The interval from diagnosis to surgery varied from 4 h to 16 days (median: 3 days). Ultrasound was performed in all cases. Fifteen cases had cryptorchidism torsion, 2 cases had a soft tissue mass in the inguinal region, and 2 cases had an inguinal/abdominal teratoma. Five cases were treated with an orchidopexy, 12 cases were treated with orchiectomy, and 2 cases received resection of a testicular tumor. The 5 children with an orchidopexy were followed up from 1 month to 7 years (median: 3 years), with 1 child having a testis retraction and no blood supply. Of the 12 children who had an orchiectomy, three had delayed diagnosis due to family unawareness of the condition, while other delays were due to delayed referral from primary care facilities. The relative rarity and insufficient awareness of cryptorchidism torsion resulted in a low rate of testicular salvage. Therefore, hospitals of all levels should be fully aware of cryptorchidism with torsion and ensure a male child's genital system and inguinal region are examined to improve the success rate of testicular salvage.
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Criptorquidismo , Torsión del Cordón Espermático , Adolescente , Niño , Criptorquidismo/complicaciones , Criptorquidismo/diagnóstico , Criptorquidismo/cirugía , Hospitales , Humanos , Lactante , Masculino , Orquiectomía , Estudios Retrospectivos , Torsión del Cordón Espermático/complicaciones , Torsión del Cordón Espermático/diagnóstico , Torsión del Cordón Espermático/cirugía , Tiempo de TratamientoRESUMEN
[This corrects the article on p. 4998 in vol. 12, PMID: 33042402.].
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Mesenchymal stem cells (MSCs) and their conditioned medium attenuate renal fibrosis in an irreversible model of unilateral ureteral obstruction (UUO). However, the key components that play a role in the paracrine effects of MSCs and their mechanisms of action are not well understood. Therefore, in this study, we investigated whether exosomes released by human umbilical cord mesenchymal stem cells (hucMSC-Ex) would be able to attenuate renal fibrosis in an irreversible model of UUO and further explored potential mechanisms. In vivo, rats were divided into four groups: sham operation, sham operation transplanted with hucMSC-Ex, UUO, and UUO transplanted with hucMSC-Ex. hucMSC-Ex was administered via the left renal artery after total ligation of the left ureter. Rats were sacrificed after 14 days of obstruction. Renal function such as serum creatinine (Scr) or blood urea nitrogen (BUN) were monitored over the period. Histological changes, proliferation and apoptosis in tubular epithelial cells, and the levels of oxidative stress were measured. In vitro, NRK-52E cells were incubated with or without 5 ng/ml TGF-ß1 and co-incubated with or without hucMSC-Ex for 48 h. Apoptosis and the levels of oxidative stress of NRK-52E cells were also measured. In the UUO group, the level of BUN and Scr, and the level of apoptosis and oxidative stress were all increased. In addition, the renal tubular injury and tubulointerstitial fibrosis were evident. However, all the above indices decreased significantly after treatment with hucMSC-Ex. In vitro, hucMSC-Ex significantly inhibited TGF-ß1-induced apoptosis of NRK-52E cells by altering the production of ROS. Furthermore, it was observed that hucMSC-Ex inhibited apoptosis by inhibiting the activation of p38 mitogen-activated protein kinase (p38MAPK)/extracellular-signal-regulated kinase (ERK) 1/2 pathway. In conclusion, the results showed that hucMSC-Ex had positive effects towards UUO-induced renal fibrosis and apoptosis of renal tubular epithelial cells, and its mechanism of action was associated with inhibition of ROS-mediated p38MAPK/ERK signaling pathway. These data suggest the potential application of hucMSC-Ex in the treatment of chronic kidney disease, and also reveal the underlying mechanism of hucMSC-Ex action.
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Renal fibrosis is a progressive pathological process that eventually leads to end-stage renal failure with limited therapeutic options. The aim of this study was to investigate the nephron-protective effect of human umbilical cord mesenchymal stem cells (ucMSCs) on renal fibrosis. UcMSCs were intravenously injected into renal fibrosis mice induced by aristolochic acid (AA) and co-cultured with HK-2 cells induced by TGF-ß1, respectively. The kidney functions including serum creatinine (Scr) and blood urea nitrogen (BUN) levels, and histopathology were examined after treated with stem cells and normal saline as control. Immunohistochemical staining, immunofluorescent staining, and Western blot analysis were used to assessed the expression of proteins associated with epithelial to mesenchymal transition (EMT) and TGF-ß/Smad signaling pathway. The results showed that ucMSCs effectively improved the kidney function and pathological structure, reduced AA-induced fibrosis and extracellular matrix deposition. Besides, UcMSCs significantly inhibited the EMT process and TGF-ß1/Smad signaling pathway in AA-induced mice and TGF-ß1-induced HK-2 cells compared to the control (p < 0.05). Our data suggested that ucMSCs play as a nephron-protective role in anti-fibrosis through inhibiting the activation of TGF-ß1/Smad signaling pathway.
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Matriz Extracelular/metabolismo , Enfermedades Renales/cirugía , Riñón/metabolismo , Trasplante de Células Madre Mesenquimatosas , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Ácidos Aristolóquicos , Línea Celular , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Transición Epitelial-Mesenquimal , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/patología , Fibrosis , Humanos , Riñón/efectos de los fármacos , Riñón/patología , Riñón/fisiopatología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , Ratones Endogámicos C57BL , Fosforilación , Recuperación de la Función , Transducción de Señal , Factor de Crecimiento Transformador beta1/farmacología , Cordón Umbilical/citologíaRESUMEN
Biological self-assembly is crucial in the processes of development, tissue regeneration, and maturation of bioprinted tissue-engineered constructions. The cell aggregates-spheroids-have become widely used model objects in the study of this phenomenon. Existing approaches describe the fusion of cell aggregates by analogy with the coalescence of liquid droplets and ignore the complex structural properties of spheroids. Here, we analyzed the fusion process in connection with structure and mechanical properties of the spheroids from human somatic cells of different phenotypes: mesenchymal stem cells from the limbal eye stroma and epithelial cells from retinal pigment epithelium. A nanoindentation protocol was applied for the mechanical measurements. We found a discrepancy with the liquid drop fusion model: the fusion was faster for spheroids from epithelial cells with lower apparent surface tension than for mesenchymal spheroids with higher surface tension. This discrepancy might be caused by biophysical processes such as extracellular matrix remodeling in the case of mesenchymal spheroids and different modes of cell migration. The obtained results will contribute to the development of more realistic models for spheroid fusion that would further provide a helpful tool for constructing cell aggregates with required properties both for fundamental studies and tissue reparation.