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PURPOSE: To investigate the value of diffusion-weighted imaging (DWI) in assessing dynamic changes of major salivary gland function during follow-up post radiotherapy (RT) in nasopharyngeal carcinoma (NPC) patients. MATERIALS AND METHODS: 31 consecutive patients with pathologically confirmed NPC scheduled for RT underwent six routine follow-up MRI examinations including DWI sequence prior to (pre-RT) and 1, 3, 6, 9, and 12 months post RT. Mean apparent diffusion coefficient (ADC) values of bilateral parotid glands (PGs) and submandibular glands (SMGs) were measured. Objective measurement of salivary flow rate (SFR) under unstimulated (uSFR) and stimulated conditions (sSFR) as well as subjective xerostomia assessment according to a patient-rated questionnaire were conducted before each MRI. Variance analysis was used to evaluate dynamic changes of ADC, SFR and xerostomia questionnaire summary scores (XQ-sum) at different timepoints and the correlation between ADC and XQ-sum. Pearson's correlation test was used to evaluate the correlations between pre- and post-RT changes of ADC (ΔADC) and SFR (ΔSFR) or mean RT dose. RESULTS: At each timepoint, ADCs of PGs were significantly lower than of SMGs, uSFR was significantly lower than sSFR. For both PGs and SMGs, ADCpost-RT were all higher than ADCpre-RT, with significant differences. ADC1m-post-RT initially increased and changed little to ADC3m-post-RT, ADC6m-post-RT, ADC9m-post-RT, and ADC12m-post-RT, then gradually declined over time. The dynamic change trends of SFR were negatively paralleled to those of ADC, while that of XQ-sum was similar. Dose-response relationships were detected between salivary gland mean RT dose and ΔADC. In PGs, negative correlations between ΔsSFR9m-post-RT and ΔADC9m-post-RT, and ΔsSFR12m-post-RT and ΔADC12m-post-RT were detected. In SMGs, negative correlations between ΔsSFR12m-post-RT and ΔADC12m-post-RT, and ΔuSFR12m-post-RT and ΔADC12m-post-RT were also detected. The ADCs of patients with severe subjective xerostomia were significantly higher, while patients with moderate subjective xerostomia presented a tendency toward higher ADCs compared to those with mild xerostomia from 6 to 12 months post RT. CONCLUSION: As part of routine follow-up MRI in NPC patients, DWI might be a promising modality for follow-up assessing the dynamic changes of major salivary gland function and might be more powerful in the late post-RT period.
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Quimiorradioterapia , Imagem de Difusão por Ressonância Magnética , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Radioterapia de Intensidade Modulada , Glândulas Salivares/diagnóstico por imagem , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Imagem de Difusão por Ressonância Magnética/métodos , Docetaxel/administração & dosagem , Feminino , Seguimentos , Humanos , Irradiação Linfática , Metástase Linfática/radioterapia , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/secundário , Estudos Prospectivos , Lesões por Radiação/etiologia , Glândulas Salivares/fisiopatologia , Salivação/efeitos da radiação , Xerostomia/etiologia , Adulto JovemRESUMO
OBJECTIVES: To investigate the value of diffusion tensor imaging (DTI) and tractography in renal allografts at the early stage after kidney transplantation. METHODS: This study was approved by the institutional ethical review committee, and written informed consent was obtained. A total of 54 renal allograft recipients 2-3 weeks after transplantation and 26 age-matched healthy volunteers underwent renal DTI with a 3.0-T magnetic resonance imaging (MRI) system. Recipients were divided into three groups according to the estimated glomerular filtration rate (eGFR). Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the cortex and medulla were measured and compared among the groups. Whole-kidney tractography was performed. Correlation of eGFR with diffusion parameters was evaluated. RESULTS: In allografts with stable function, the medullary ADC was higher and the cortical FA was lower (p < 0.001) than in healthy kidneys. The cortical ADC, medullary ADC and FA decreased as the allograft function declined, and with a positive correlation with eGFR (p < 0.001); cortical FA did not. Tractography demonstrated a decrease of tract density in impaired functional allografts. CONCLUSIONS: Renal DTI produces reliable results to assess renal allograft function at the early stage after transplantation. KEY POINTS: ⢠DTI and tractography can evaluate renal allograft function at an early stage ⢠Medullary FA, cortical and medullary ADC can effectively evaluate allograft function ⢠Medullary FA, cortical and medullary ADC are correlated with eGFR in renal allografts ⢠Medullary ADC increased and cortical FA decreased in stable allografts compared to control subjects ⢠Medullary FA, cortical and medullary ADC decreased and allograft function declined.
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Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Transplante de Rim , Rim/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Transplante Homólogo , Adulto JovemRESUMO
Gas chromatography is now the primary analysis method for the coal liquefaction oil. However, a simple and rapid quantification/qualification of the coal liquefaction oil can hardly be realized, because the coal liquefaction oil is in a heterogeneous state with a long boiling range. The aim of this study was to establish a rapid and accurate method for the quantification of phenolic compounds, aromatics and aliphatic hydrocarbons in coal liquefaction oil. A representative composition of coal liquefaction light oil, i.e., the distillate fractions of the boiling point range 180-200 degrees C, was chosen as the investigated object. The characteristic absorption peaks of the samples in the UV spectra (200-400 nm) were examined, using three kinds of solvents, cyclohexane, ethanol, 50 Wt% NaOH/ethanol mixture. Among them, the mixture solvent provided the best performance, where the aromatics interfered minimally with the quantification of phenolic compounds by avoiding the peak overlapping problem. By comparison of the UV absorption standard curves between the standard compounds (phenol, m-cresol, p-cresol and o-cresol) and the phenolic mixtures in coal liquefaction oil, m-cresol was selected for the quantification of phenolic compounds in coal liquefaction oil. The content of phenolic compounds was determined to be 32.14% according to the calibration curve of m-cresol at 290 nm, and this result is largely consistent with that determined by weighing after separation. Based on UV and GC analysis of the dephenolized oil, the standard curve of tetrahydronaphthalene at 266 nm was used for the quantification of aromatic hydrocarbons in coal liquefaction oil. The contents of aromatic and aliphatic hydrocarbons were determined to be 44.91% and 22.95%, respectively. To verify the accuracy of the method, recovery of added standards in the oil samples was determined and found to be 104.3%-110.75% and 84.3%-91.75% for phenolic compounds and aromatics, respectively. These results indicate that the contents of phenolic compounds and aromatics can be determined simultaneously with the UV standard curves of m-cresol and tetrahydronaphthalene, respectively, and the aliphatic compounds can be determined by difference.
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Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis are common intestinal pathogens that infect humans and animals. To date, research regarding these three protozoa in the Ningxia Hui Autonomous Region (Ningxia) has mostly been limited to a single pathogen, and comprehensive data on mixed infections are unavailable. This study aimed to evaluate the zoonotic potential of these three protozoa. In this study, small subunit ribosomal RNA (SSU rRNA) and 60 kDa glycoprotein (gp60) genes of Cryptosporidium; internal transcribed spacer (ITS) gene of E. bieneusi; and SSU rRNA, glutamate dehydrogenase (gdh), triosephosphate isomerase (tpi), and beta-giardin (bg) genes of G. duodenalis were examined. DNA extraction, polymerase chain reaction, and sequence analysis were performed on fecal samples collected from 320 dairy cattle at three intensive dairy farms in Ningxia in 2021 to determine the prevalence and genetic characteristics of these three protozoa. The findings revealed that 61.56% (197/320) of the samples were infected with at least one protozoan. The overall prevalence of Cryptosporidium was 19.38% (62/320), E. bieneusi was 41.56% (133/320), and G. duodenalis was 29.38% (94/320). This study identified four Cryptosporidium species (C. bovis, C. andersoni, C. ryanae, and C. parvum) and the presence of mixed infections with two or three Cryptosporidium species. C. bovis was the dominant species in this study, while the dominant C. parvum subtypes were IIdA15G1 and IIdA20G1. The genotypes of E. bieneusis were J, BEB4, and I alongside the novel genotypes NX1-NX8, all belonging to group 2, with genotype J being dominant. G. duodenalis assemblages were identified as assemblages E, A, and B, and a mixed infection involving assemblages A + E was identified, with assemblage E being the dominant one. Concurrently, 11 isolates formed 10 different assemblage E multilocus genotypes (MLGs) and 1 assemblage A MLG and assemblage E MLGs formed 5 subgroups. To the best of our knowledge, this is the first report on mixed infection with two or three Cryptosporidium species in cattle in Ningxia and on the presence of the C. parvum subtype IIdA20G1 in this part of China. This study also discovered nine genotypes of E. bieneusis and novel features of G. duodenalis assemblages in Ningxia. This study indicates that dairy cattle in this region may play a significant role in the zoonotic transmission of Cryptosporidium spp., E. bieneusi, and G. duodenalis.
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Doenças dos Bovinos , Criptosporidiose , Cryptosporidium , Enterocytozoon , Giardia lamblia , Giardíase , Microsporidiose , Animais , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Bovinos , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Cryptosporidium/classificação , Giardia lamblia/genética , Giardia lamblia/isolamento & purificação , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , China/epidemiologia , Prevalência , Microsporidiose/veterinária , Microsporidiose/epidemiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/microbiologia , Giardíase/veterinária , Giardíase/epidemiologia , Giardíase/parasitologia , Feminino , Fezes/parasitologia , Fezes/microbiologiaRESUMO
PURPOSE: Aim to create and validate a comprehensive nomogram capable of accurately predicting the transition from moderate-severe to normal-mild xerostomia post-radiotherapy (postRT) in patients with nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: We constructed and internally verified a prediction model using a primary cohort comprising 223 patients who were pathologically diagnosed with NPC from February 2016 to December 2019. LASSO regression model was used to identify the clinical factors and relevant variables (the pre-radiotherapy (XQ-preRT) and immediate post-radiotherapy (XQ-postRT) xerostomia questionnaire scores, as well as the mean dose (Dmean) delivered to the parotid gland (PG), submandibular gland (SMG), sublingual gland (SLG), tubarial gland (TG), and oral cavity). Cox proportional hazards regression analysis was performed to develop the prediction model, which was presented as a nomogram. The models' performance with regard to calibration, discrimination, and clinical usefulness was evaluated. The external validation cohort comprised 78 patients. RESULTS: Due to better discrimination and calibration in the training cohort, age, gender, XQ-postRT, and Dmean of PG, SMG, and TG were included in the individualized prediction model (C-index of 0.741 (95% CI:0.717 to 0.765). Verification of the nomogram's performance in internal and external validation cohorts revealed good discrimination (C-index of 0.729 (0.692 to 0.766) and 0.736 (0.702 to 0.770), respectively) and calibration. Decision curve analysis revealed that the nomogram was clinically useful. The 12-month and 24-month moderate-severe xerostomia rate was statistically lower in the SMG-spared arm (28.4% (0.230 to 35.2) and 5.2% (0.029 to 0.093), respectively) than that in SMG-unspared arm (56.8% (0.474 to 0.672) and 12.5% (0.070 to 0.223), respectively), with an HR of 1.84 (95%CI: 1.412 to 2.397, p = 0.000). The difference in restricted mean survival time for remaining moderate-severe xerostomia between the two arms at 24 months was 5.757 months (95% CI, 3.863 to 7.651; p = 0.000). CONCLUSION: The developed nomogram, incorporating age, gender, XQ-postRT, and Dmean to PG, SMG, and TG, can be used for predicting recovery from moderate-severe xerostomia post-radiotherapy in NPC patients. Sparing SMG is highly important for the patient's recovery.
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Neoplasias de Cabeça e Pescoço , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Xerostomia , Humanos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias de Cabeça e Pescoço/etiologia , Nomogramas , Radioterapia de Intensidade Modulada/efeitos adversos , Xerostomia/etiologia , Neoplasias Nasofaríngeas/radioterapiaRESUMO
PURPOSE: To identify the clinical significance of sparing submandibular glands (SMG) for the amelioration of acute xerostomia using diffusion kurtosis imaging (DKI) in nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy (HT). MATERIALS AND METHODS: The prospective study enrolled 42 participants treated with HT. All patients underwent five times of DKI scans before HT (pre-HT), in the middle of the HT course (mid-HT), immediately after HT (post-HT), and 1 months (1m-HT), 3 months post-HT(3m-HT). Mean diffusion (MD) and mean kurtosis (MK) of SMG, parotid glands (PG) and sublingual glands (SLG), saliva flow rate measures under resting (uSFR) and stimulated condition (sSFR), and xerostomia questionnaire scores (XQ) were recorded. Comparisons between the SMG-spared and -unspared groups were analyzed using two-factor repeated-measures ANOVA for the group as the inter-subject factor and the time as the intra-subject factor. RESULTS: When sparing SMG, the dose of spared-SMG and ipsilateral SLG was lower compared to that of unspared glands (p < 0.001). MD of spared-SMG and ipsilateral SLG in SMG-spared group were lower than that of SMG-unspared group (the simple effect for the group, p-value at mid-HT, post-HT, 1m- and 3m-HT was 0.014, 0.011, 0.000 and 0.000, respectively), MK of spared-SMG was higher conversely (the main effect for the group, p < 0.001), while uSFR and sSFR were significantly lower in SMG-unspared group (the main effect for the group, p = 0.002, and p = 0.045, respectively). No significant differences were detected in MK of SLG, MD/MK of PG, and XQ between the two groups (the main effect for the group, p values were 0.9, 0.37, 0.15, 0.86, respectively). There were significant differences in the effect of the time for all MD/MK of the salivary glands and for uSFR, sSFR, and XQ between the SMG-spared and -unspared groups (p values were all <0.001). CONCLUSION: Sparing SMG is of great clinical significance in alleviating acute xerostomia for NPC patients treated by helical tomotherapy as evaluated by diffusion kurtosis imaging and saliva flow rate.
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Neoplasias de Cabeça e Pescoço , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Xerostomia , Neoplasias de Cabeça e Pescoço/etiologia , Humanos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Glândula Parótida , Estudos Prospectivos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Glândula Submandibular/diagnóstico por imagem , Xerostomia/etiologia , Xerostomia/prevenção & controleRESUMO
Purpose: The aim of this study was to identify the efficacy of diffusion kurtosis imaging (DKI) in tracking and monitoring the dynamic change of parotid glands (PGs), submandibular glands (SMGs), sublingual glands (SLGs), and acute xerostomia in nasopharyngeal carcinoma (NPC) patients treated with induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT). Methods: The prospective study recruited 42 participants treated with IC+CCRT. All patients underwent DKI scanning six times: before IC, before RT, in the middle of the RT course, immediately after RT, and 1 and 3 months post-RT. Mean diffusion coefficient (MD) and mean kurtosis (MK) of PG, SMG, SLG, saliva flow rate measured under resting (uSFR) and stimulated condition (sSFR), and xerostomia questionnaire (XQ) scores were recorded. Results: At each time point, sSFR was significantly higher than uSFR (p < 0.05 for all). MD of the salivary glands and XQ scores increased over time while MK, uSFR, and sSFR decreased. After IC, the significant differences were detected in MD and MK of bilateral SMG and MK of the left SLG (p < 0.05 for all), but not in MD and MK of PG, uSFR, sSFR, and XQ scores. After RT, sSFR at 1m-RT decreased significantly (p = 0.03) while no significant differences were detected in uSFR and XQ scores. Moderate-strong correlations were detected in ΔMD-PG-R%, ΔMK-PG-R%, ΔMD-PG-L%, ΔMK-PG-L%, ΔMD-SMG-R%, ΔMK-SMG-R%, ΔMD-SMG-L%, ΔMK-SMG-L%, and ΔMD-SLG-R%, with correlation coefficients (p < 0.05 for all) ranging from 0.401 to 0.714. ΔuSFR% was correlated with ΔMD-SMG% (p = 0.01, r = -0.39), ΔMD-SLG% (p < 0.001, r = -0.532), and ΔMK-SMG% (p < 0.001, r = -0.493). ΔsSFR% correlated with ΔMD-PG% (p = 0.001, r = -0.509), ΔMD-SMG% (p = 0.015, r = -0.221), and ΔMK-PG% (p < 0.001, r = 0.524). ΔXQ% was only correlated with ΔMK-PG% (p = 0.004, r = 0.433). Conclusion: DKI is a promising tool for tracking and monitoring the acute damage of PG, SMG, and SLG induced by IC+CCRT in NPC patients.
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BACKGROUND: Functional MRI (fMRI) parameters analysis has been proven to be a promising tool of predicting therapeutic response to induction chemotherapy (IC) in nasopharyngeal carcinoma (NPC). The study was designed to identify and compare the value of fMRI parameters in predicting early response to IC in patients with NPC. METHODS: This prospective study enrolled fifty-six consecutively NPC patients treated with IC from January 2021 to May 2021. Conventional diffusion weighted imaging (DWI), diffusion kurtosis imaging (DKI), intravoxel incoherent motion (IVIM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) protocols were performed before and after IC. Parameters maps (ADC, MD, MK, Dslow, Dfast, PF, Ktrans, Ve and Kep) of the primary tumor were calculated by the Functool post-processing software. The participants were classified as responding group (RG) and non-responding group (NRG) according to Response Evaluation Criteria in Solid Tumors 1.1. The fMRI parameters were compared before and after IC and between RG with NRG. Logistic regression analysis and ROC were performed to further identify and compare the efficacy of the parameters. RESULTS: After IC, the mean values of ADC(p < 0.001), MD(p < 0.001), Dslow(p = 0.001), PF(p = 0.030) and Ve(p = 0.003) significantly increased, while MK(p < 0.001), Dfast(p = 0.009) and Kep(p = 0.003) values decreased dramatically, while no significant difference was detected in Ktrans(p = 0.130). Compared with NRG, ADC-pre(p < 0.001), MD-pre(p < 0.001) and Dslow-pre(p = 0.002) values in RG were lower, while MK-pre(p = 0.017) values were higher. The areas under the ROC curves for the ADC-pre, MD-pre, MK-pre, Dslow-pre and PRE were 0.885, 0.855, 0.809, 0.742 and 0.912, with the optimal cutoff value of 1210 × 10- 6 mm2/s, 1010 × 10- 6 mm2/s, 832 × 10- 6, 835 × 10- 6 mm2/s and 0.799 respectively. CONCLUSIONS: The pretreatment conventional DWI (ADC), DKI (MD and MK), and IVIM (Dslow) values derived from fMRI showed a promising potential in predicting the response of the primary tumor to IC in NPC patients. TRIAL REGISTRATION: This study was approved by ethics board of the Chinese PLA General Hospital, and registered on January 30, 2021, in Chinese Clinical Trial Registry ( ChiCTR2100042863 ).
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Imagem de Difusão por Ressonância Magnética/métodos , Quimioterapia de Indução , Imageamento por Ressonância Magnética/métodos , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/tratamento farmacológico , Adolescente , Adulto , Idoso , Benchmarking , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do TratamentoRESUMO
PURPOSE: To verify clinical significance of submandibular gland (SMG)-sparing during helical tomotherapy (HT) for nasopharyngeal carcinoma (NPC) from the perspective of imaging by using diffusion weighted imaging (DWI). MATERIALS AND METHODS: In this prospective study, 60 NPC patients scheduled for radical SMG-sparing HT were enrolled. All patients underwent DWI examinations prior to HT (pre-HT) and 1, 3, 6, 9, 12 months post HT. Mean apparent diffusion coefficient (ADC) values of bilateral parotid glands (PGs) and submandibular glands (SMGs) were measured. Differences of ADC and changes of ADC pre and pro HT (ΔADC) among SMG-spared, SMG-unspared and PGs were compared and the associations betweenΔADC and variations of patient-rated xerostomia questionnaire summary scores (XQ-sum) were further tested. RESULTS: ADCpost-HT and ΔADCpost-HT of SMG-spared were both much lower than of SMG-unspared and a strong dose-response relationship was detected between mean radiation dose and ΔADC of SMGs. Dynamic change trends of PGs, SMG-spared and SMG-unspared were similar, with initial increase at 1 m-post-HT followed by little change at 3 m-post-HT and then gradual decrease over time. But for SMG-unspared, there was no obvious change of ADC from 6 m-post-HT to 12 m-post-HT. The dynamic change trend of XQ-sum was nearly in line with that of ADC on the whole. And a positive correlation between mean ΔADC1m-post-HT of bilateral SMGs and variation of XQ-sum1m-post-HT in patients with bSMG-unspared were found (r = 0.693, P < 0.001). Multivariate stepwise regression analysis showed that whether spared SMG or not was the only independent predictor correlated to XQ-sumpost-HT at each follow-up timepoint. CONCLUSION: SMG-sparing technique could significantly improve subjective xerostomia post HT in NPC patients from the perspective of imaging.
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Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Xerostomia , Humanos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Glândula Parótida , Estudos Prospectivos , Glândula Submandibular/diagnóstico por imagem , Xerostomia/etiologiaRESUMO
Tumor local invasion is the first step of metastasis cascade which remains the key obstacle for cancer therapy. Collective cell migration plays a critical role in tumor invading into surrounding tissues. In vitro assays fail to assess collective invasion in a real time manner. Herein we aim to develop a three-dimensional (3D) microfluidic cell invasion model to determine the dynamic process. In this model, collective invasion of breast cancer cells is induced by the concentration gradient of fetal bovine serum. We find that breast cancer cells adopt a collective movement rather than a random manner when the cells invade into extracellular matrix. The leading cells in the collective movement exhibit an increased expression of an Aurora kinase family protein - AURKA compared with the follower cells. Inhibition of AURKA kinase activity by VX680 or AKI603 significantly reduces the phosphorylation of ERK1/2 (Thr202/Tyr204) and collective cohort formation. Together, our study illustrates that AURKA acts as a potential therapeutic target for suppressing the process of tumor collective invasion. The 3D microfluidic cell invasion model is a reliable, measurable and dynamic platform for exploring potential drugs to inhibit tumor collective invasion.
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Aurora Quinase A/antagonistas & inibidores , Aurora Quinase A/metabolismo , Movimento Celular/efeitos dos fármacos , Microfluídica , Inibidores de Proteínas Quinases/farmacologia , Aurora Quinase A/genética , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Imunofluorescência , Expressão Gênica , Humanos , Microfluídica/instrumentação , Microfluídica/métodosRESUMO
Long noncoding RNA-H19 (H19), an imprinted oncofetal gene, has a central role in carcinogenesis. Hitherto, the mechanism by which H19 regulates cancer stem cells, remains elusive. Here we show that breast cancer stem cells (BCSCs) express high levels of H19, and ectopic overexpression of H19 significantly promotes breast cancer cell clonogenicity, migration and mammosphere-forming ability. Conversely, silencing of H19 represses these BCSC properties. In concordance, knockdown of H19 markedly inhibits tumor growth and suppresses tumorigenesis in nude mice. Mechanistically, we found that H19 functions as a competing endogenous RNA to sponge miRNA let-7, leading to an increase in expression of a let-7 target, the core pluripotency factor LIN28, which is enriched in BCSC populations and breast patient samples. Intriguingly, this gain of LIN28 expression can also feedback to reverse the H19 loss-mediated suppression of BCSC properties. Our data also reveal that LIN28 blocks mature let-7 production and, thereby, de-represses H19 expression in breast cancer cells. Appropriately, H19 and LIN28 expression exhibits strong correlations in primary breast carcinomas. Collectively, these findings reveal that lncRNA H19, miRNA let-7 and transcriptional factor LIN28 form a double-negative feedback loop, which has a critical role in the maintenance of BCSCs. Consequently, disrupting this pathway provides a novel therapeutic strategy for breast cancer.
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Neoplasias da Mama/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Neoplasias da Mama/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/biossíntese , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , RNA Longo não Codificante/biossíntese , Proteínas de Ligação a RNA/biossínteseRESUMO
2,3,4',5-tetrahydroxystilbene-2-0-ß-D glucoside (TSG) has been recognized to suppress the proliferation of vascular smooth muscle cells (VSMCs). The aim of the present study was to determine whether TSG inhibits neointimal hyperplasia in a rat carotid arterial balloon injury model. Balloon injury was induced in the left common carotid artery of rats. TSG (30, 60, 120 mg/kg/day) was treated from 3 days prior to, until 14 days after the induction of balloon injury. The ratio of intima-to-media was significantly reduced in the TSG-treated rats at 14 days after the induction of injury, which was associated with reduced expressions of proliferating cell nuclear antigen (PCNA), α-smooth muscle actin (α-SMA) and platelet-derived growth factor-BB (PDGF-BB), as markers of VSMCs proliferation and migration. Additionally, TSG significantly inhibited PDGF-BB induced cell migration in cultured VSMCs. Furthermore, we explored the underlying mechanisms for such effects of TSG. The result showed that TSG markedly reduced balloon injury-induced AKT, extracellular signal-regulated kinase (ERK1/2) and nuclear factor kappaB (NF-κB) activation as well as mRNA expressions of c-myc, c-fos and c-jun, which is important signal pathway for VSMCs proliferation. And in both vivo and vitro model, TSG markedly regulated matrix metalloproteinase-2, 9 expressions and collagen I, III expressions, which are key factors in extracellular matrix for VSMCs migration. These results suggest that the anti-proliferative and anti-migrative effects of TSG on VSMCs could help to explain the beneficial effects of TSG on neointima hyperplasia induced by balloon injury.