[Clinical and radiographic effect of simultaneously labial and lingual augmented corticotomy: a prospective case series study]

Objective: To investigate soft-and hard-tissue changes after simultaneously labial and lingual augmented corticotomy in patients with insufficient alveolar bone thickness of lower anterior teeth both in labial and lingual side during orthodontic treatment. Methods: From January 2021 to June 2022, 10 patients [2 males and 8 females, (26.2±3.1) years old] who received orthodontic and orthognathic combined treatment from the Fourth Clinical Division, Peking University School and Hospital of Stomatology were selected. The alveolar bone thickness of lower anterior teeth both in labial and lingual side in these patients was less than 0.5 mm according to cone-beam CT examination before or during treatment, and 60 lower anterior teeth were included. The 10 patients were treated with simultaneously labial and lingual augmented corticotomy. The differences in gingival recession, papilla index and the differences in labial and lingual alveolar bone thickness of lower anterior teeth were compared. Results: Six months after surgery, the alveolar bone thicknesses at the 4 mm under cemento-enamel junction (CEJ), 8 mm under CEJ and at the apical level [labial side: (1.02±0.39), (2.22±0.89) and (4.87±1.35) mm; lingual side: (1.07±0.46), (2.31±1.04) and (3.91±1.29) mm] were significantly higher than that before surgery [labial side: (0.02±0.09), (0.06±0.21) and (2.71±1.33) mm]; lingual side: (0.14±0.29), (0.40±0.52) and (2.13±1.02) mm] (P<0.001), respectively. The increases in alveolar bone thickness of central incisors [apical level on labial side: (2.53±1.20) mm, 8 mm under CEJ on lingual side: (2.27±1.24) mm, apical level on lingual side: (2.66±1.49) mm] and lateral incisors [apical level on labial side: (2.42±1.30) mm, 8 mm under CEJ on lingual side: (2.28±0.92) mm, apical level on lingual side: (1.94±1.15) mm] were significantly higher than that of canines [apical level on labial side: (1.52±1.47) mm, 8 mm under CEJ on lingual side: (1.17±1.09) mm,apical level on lingual side: (0.74±1.37) mm] (P<0.01). There were no significant differences in the degree of gingival recession [labial side before surgery: (0.72±0.88) mm, lingual side before surgery: (0.80±1.09) mm; labial side 6 months after surgery: (0.72±0.81) mm,lingual side 6 months after surgery: (0.89±0.21) mm] and gingival papilla index [before surgery: 1.00(0.75, 2.00); 6 months after surgery: 1.00(1.00, 2.00) ] between pre-operation and 6 months after surgery (P>0.05). No serious complications occurred. Conclusions: The method used in this article for simultaneously labial and lingual augmented corticotomy was safe and feasible. This surgery has positive clinical significance for the stability of the periodontal tissue in orthodontic treatment for patients with alveolar bone thickness less than 0.5 mm of lower anterior teeth both in labial and lingual side.

Molecular Imaging of Radiation-Induced Lung Injury Using [18F]AlF Labeled Polypeptide Targeting C-X-C-Chemokine-Receptor-Type-4

PURPOSE/OBJECTIVE(S)

Radiation-induced lung injury (RILI) is a severe side effect of radiotherapy (RT) for thoracic malignancies and we currently lack established means for the early detection of RILI. In this study, we synthesized a new tracer, [18F]AlF-NOTA-QHY-04, targeting C-X-C-chemokine-receptor-type-4 (CXCR4) and investigated the feasibility of using this tracer in positron emission tomography combined with computed tomography (PET/CT) for detecting RILI.

MATERIALS/METHODS

An RILI model was established using a high-dose single RT (50 Gy/Fraction) to the right lung of female Wistar rats. Experimental animals were scanned with [18F]AlF-NOTA-QHY-04 PET/CT and [18F]FDG PET/CT at various time-points post-RT. MicroCT imaging was conducted weekly till 11 weeks post-RT. Dynamic, competition, autoradiography and histopathological studies were performed on day 14 post-RT. Biodistribution study was further performed on day 18 post-RT. Lung QHY-04 uptake was analyzed in twelve patients with radiation pneumonia, developed during or after thoracic RT.

RESULTS

The yield of [18F]AlF-NOTA-QHY-04 was 28.5-43.2%, and the specific activity was 27-33 GBq/μmol. Significantly increased [18F]AlF-NOTA-QHY-04 uptake in the damaged lung compared with that in the normal lung was observed in the experimental animal model on 6 post-RT and peaked on day 14 post-RT (0.96 ± 0.06 vs. 0.50 ± 0.05 %ID/mL, P<0.05), whereas no apparent uptake of [18F]FDG was shown on day 7 and 15 post-RT. Significant intense [18F]AlF-NOTA-QHY-04 uptake was confirmed by autoradiography. No significant difference in CT density was observed between the damaged and normal lung tissues until six weeks post-RT. Immunofluorescence staining demonstrated expression of CXCR4 was significantly increased in the damaged lung tissue, which correlated with results obtained from hematoxylin-eosin and Masson's trichrome staining. Maximum standardized uptake values (SUVmax) were significantly higher in the irradiated lung compared with that in the normal lung in 12 patients with radiation pneumonia (3.07 ± 0.86 vs. 0.585 ± 0.17, P<0.001). SUVmax of patients with grade 2 RILI was significantly higher than that of patients with grade 1 RILI (3.30 ± 0.65 vs. 1.64 ± 0.08, P<0.05).

CONCLUSION

This study indicated that [18F]AlF-NOTA-QHY-04 PET/CT imaging can detect RILI noninvasively and earlier than [18F]FDG PET/CT in a rat model. Clinical studies verified its' feasibility, suggesting the clinical potential of [18F]AlF-NOTA-QHY-04 as a PET/CT tracer for early monitoring of RILI.

Development and Validation of CT-Based Dose-Volume-Radiomics Nomogram for Radiation Induced Hypothyroidism in Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

Several studies reported hypothyroidism occurred in 40-50% of patients who were treated with neck irradiation. Post-radiation hypothyroidism impairs quality of life, increases the risk of cardiac complications, and requires lifelong thyroxine replacement in affected patients. At present, radiation dose-volume constraints of thyroid gland are used to predict thyroid function outcomes in patients with nasopharyngeal carcinoma (NPC). However, it is limited by (a) inferior predictive power, (b) a lack of analyzing individualized thyroid characteristics as a categoriad to predict radiation induced hypothyroidism (RIHT). In this study, we firstly developed and validated CT-based dose-volume-radiomics nomogram to predict RIHT in patients with NPC.

MATERIALS/METHODS

A total of 451 NPC patients who underwent definitive radiotherapy were randomly assigned into the training (n = 338) and validation set (n = 113) in a 3:1 ratio. Dose-volume parameters, including the thyroid volume, mean dose (Dmean), percentage of the volume that received xGy of radiation (Vx), and the absolute volume that was spared from xGy of radiation (Vsx), were collected from radiotherapy planning databases. We defined primary hypothyroidism as an elevated TSH serum level (> 4.94 mIU/L) in combination with a normal or low serum FT4 level, regardless of symptoms. 1316 CT radiomic features were extracted and selected to construct the radiomics signature (RS). A CT-based nomogram was established by integrating clinical factors, dose-volume parameters and radiomics signature in training set and was tested in validation set.

RESULTS

With a median follow-up period of 68 months, 301 (66.7%) patients developed RIHT. Compared with other dose-volume parameters including thyroid volume, V30, V50, Dmean, Vs45, Vs50, the thyroid volume spared from 60Gy (Vs60) had best power to predict RIHT. The radiomics signature constructed by 8 selected radiomic features showed better prognostic performance than Vs60 for predicting RIHT in training set (RIHT vs. Vs60, C-index: 0.69 vs. 0.58) and internal validation set (C-index: 0.65 vs. 0.55). Patients were stratified into high- and low-risk groups by median radiomic signature. Patients in high-risk group had higher rate of RIHT than patients in low-risk group (training set:61% vs.39%, P<0.05; validation set: 73% vs.32%, P<0.05). The nomogram established by integrating radiomics signature with Vs60 showed optimal prognostic performance with C-index of 0.71 in training, 0.66 in validation set. Calibration curves showed good agreement.

CONCLUSION

CT-based dose-volume-radiomics nomogram provided an excellent prognostic tool for predict incidence rate of RITH in patients with NPC received definitive radiotherapy.

A Self-Attention-Based Neural Network for Predicting Immune Checkpoint Inhibitors Response

PURPOSE/OBJECTIVE(S)

Cancer cells evade immune system by negatively regulating T cells via immune checkpoints (e.g., PD-1). By blocking these checkpoints, the ability of immune system to recognize and kill cancer cells restores. Individual response rate of checkpoint blockade varies among patients, with 50%-80% in specific types of cancer such as melanoma, while only 15%-30% in most other tumors. Yet it is still an open question what is the set of biomarkers that are crucial to the response to immune checkpoint inhibitors (ICI). The overall goal of this study is to develop and validate a biologically-aware interpretable deep learning model to identify the biomarkers that can predict the survival outcome to ICI treatment.

MATERIALS/METHODS

The self-attention mechanism could yield interpretable results where important biomarkers may have more "attention". However, in classical self-attention mechanism, the prior biological knowledge of protein interactions (PPI) and gene pathways are not incorporated. In this study, we propose a weighted biologically-aware attention score, where it is weighted against the gene centrality and pathway length. The genes that are closely connected to mutated genes receive 'high attention', while the genes that are far away from mutated genes along the pathway receive "lower attention". We then train, validate and test our model using 1,660 patients of nine types of cancer. To validate the prediction, 1. We evaluate the accuracy via concordance index. 2. We identified the genes that receive high attention and verify their functions in existed literature. 3. We perform sanity check by removing these genes from the data, re-training and predicting again, and comparing the prediction accuracy.

RESULTS

Our framework has achieved an average accuracy (measured via c-index) of 0.60 ± 0.06 for NSCLC and 0.58 ± 0.07 for melanoma, which is superior to both the gold standard COX-PH model (0.57 ± 0.06 for NSCLC and 0.53 ± 0.03 for melanoma) and DeepSurv (0.54 ± 0.05 for NSCLC and 0.51 ± 0.10 for melanoma). Genes that receive high attention have been validated by supporting literature, which provides an additional means of verifying the prediction in comparison to "black box" deep learning models, where there is no way to comprehend the reason behind predictions. Removing the top 8% high-attention genes (∼25 genes) from the data while using the remaining 92% for making predictions resulted in a drop in accuracy to 0.55 ± 0.073 for NSCLC and 0.56 ± 0.03 for melanoma, underscoring the significance of these genes. Patient stratification is also performed by dividing patients into responders and non-responders based on prediction score.

CONCLUSION

In this study, we propose and validate a biologically-aware self-attention based deep learning model which outperforms commonly-used survival models. Additionally, this tool has the potential to identify key biomarkers while assist in clinical decision-making, which demonstrates a promising step for immunotherapy response prediction.

Geographic variation and trends in prevalence of obesity among US adolescents, 2016-2021

OBJECTIVE

Recent updates of geographic variations, trends, and sociodemographic disparities in obesity prevalence among US adolescents are limited. The study aimed to fill those research gaps.

STUDY DESIGN

Serial cross-sectional analysis of the US nationally representative study.

METHODS

Data from six cycles of the National Survey of Children's Health (2016, 2017, 2018, 2019, 2020, and 2021) with information on physical health at the national and state level were used. A total of 107,274 adolescents aged 10-17 years old were included with sociodemographic data (age, sex, race/ethnicity, parental education level, and family income) and state of residence. Logistic regression models were used to estimate the odds ratios (ORs) associated with obesity across sociodemographic groups. In addition, ORs were calculated to compare obesity rates between the pandemic period (2020-2021) and the pre-pandemic period (2018-2019) overall and by sociodemographic subgroups. Survey analysis procedures were used to account for complex survey designs to derive representative estimates.

RESULTS

From 2016 to 2021, obesity prevalence increased from 16.1% (95% confidence interval [CI], 14.9%-17.4%) to 17.6% (95% CI, 16.4%-18.9%) (P-trend = 0.04). The combined prevalence of obesity varies substantially by state, from 9.34% (95% CI, 6.96%-12.4%; Colorado) to 27.1% (95% CI, 23.1%-31.5%; Mississippi) for adolescents aged 10-13 years and ranged from 9.86% (95% CI, 7.63%-12.7%; Utah) to 22.4% (95% CI, 19.0%-26.1%; West Virginia) for adolescents aged 14-17 years. Except for subgroups male gender and parents with college degrees or above, the prevalence of obesity showed stable trends across sociodemographic subgroups. Compared to the pre-pandemic period, the multivariable-adjusted ORs of obesity were 1.18 (95% CI, 1.06-1.32) for male adolescents, 1.16 (95% CI, 1.04-1.28) for non-Hispanic White adolescents, 1.81 (95% CI, 1.15-2.84) for non-Hispanic Asian adolescents, 1.26 (95% CI, 1.05-1.52) for adolescents whose parents had a high school education, and 1.15 (95% CI, 1.0-1.33) for adolescents whose parents had a college degree or higher.

CONCLUSIONS

The prevalence of obesity among US adolescents increased significantly between 2016 and 2021. The prevalence of obesity was relatively high in southern states. Those with low household income, low parental education, or being non-Hispanic Black or Hispanic were also more likely to be obese. Compared to the pre-pandemic period, several groups of adolescents increased their likelihood of obesity during the pandemic period.

Camrelizumab with Chemoradiotherapy for Locally Advanced Biliary Tract Cancer: Preliminary Results from A Phase II Study

PURPOSE/OBJECTIVE(S)

For locally advanced biliary tract cancer (BTC), capecitabine-based chemoradiotherapy (CRT) is commonly used but has limited benefits. Immunotherapy is potentially effective for BTC and may be synergized with CRT. Followed by gemcitabine and cisplatin (GP) consolidation chemotherapy (CT), we evaluated the safety and efficacy of combined camrelizumab and capecitabine-based CRT for locally advanced BTC.

MATERIALS/METHODS

Patients had stage II-III (T4N0M0, T1-4N+M0) BTC (per the 7th [2010] edition of the American Joint Committee on Cancer staging system) were eligible for CRT (capecitabine plus [50-60 Gy] radiotherapy), to be followed by GP CT. Camrelizumab was given concurrently with CRT. Safety was defined as the incidence and severity of adverse events (AEs), while efficacy was defined as overall survival (OS), progression-free survival (PFS), objective response rate (ORR) and disease control rate (DCR).

RESULTS

Ten patients completed the planned treatment. None experienced grade ≥3 treatment-related AEs during CRT. Grade ≥3 immune-related AEs occurred in 2 of 10 patients (20%) only during GP CT. The mean OS time was 18.2 months (95% confidence interval [CI] 12.9m-23.5m) while the median OS time was 14.1 months (95% CI 10.1m-18.1m). OS rates were 100%, 59%, 44% at 6 months, 1 year and 2 years, respectively. The ORR was 30% while the DCR was 90%. Two patients (20%) obtained OS over 2 years with partial response (25.9m, 29.1m). Median PFS time was 14.1 months (95% CI 9.3m-18.9m).

CONCLUSION

Camrelizumab in combination with concurrent CRT was well tolerated and did not impair delivery of CRT in patients with locally advanced BTC.

An Adaptive Multi-Feature Fusion Network for Predicting Overall Survival of Patients with Head and Neck Cancer

PURPOSE/OBJECTIVE(S)

Accurate prognostic prediction could allow personalized treatment to achieve optimal clinical outcome. We aimed to develop a highly predictive overall survival model, considering the complementary relationships between clinical information, traditional radiomics and deep image information, to further improve the overall prediction accuracy by constructing a richer feature set and adaptive weighting.

MATERIALS/METHODS

A total of 427 patients with Oropharyngeal Cancer (OPC) patients from the TCIA database were included. 341 cases were used for training, 86 cases were used as an independent cohort. Patient characteristics, including TMN, age, gender, HPV status, smoking or drinking status, etc. were considered as potential predictors. Traditional radiomics features of gross tumor volume (GTV) was extracted from planning CT using open-source software. In addition, a two-dimensional convolutional network (2D_CNN) was designed to extract deep image features. An adaptive multi-feature fusion network was developed to predict overall survival of patients based on three types of features. The fusion network integrates an attention mechanism to the channel dimension to obtain proper weighting of each channel in the feature graph through the fully connected network by focusing on effective feature channels and automatic learning according to the loss, thus improving the utilization rate of effective features. The model performance was evaluated using the area-under-ROC-curve (AUC), accuracy, precision, recall, f1-score.

RESULTS

The AUCs of predictive models based on clinical features, traditional radiomics features and deep image features were 0.7, 0.61 and 0.72, respectively. Combining patient characteristics, radiomic features and deep imaging features, the AUCs of the prediction models was significantly improved to 0.85 and 0.86 (with attention mechanisms) for the independent test cohort (Table 1).

CONCLUSION

The proposed adaptive multi-channel network assigned effective weights to the potential predictors, selectively enhanced useful features while suppressed irrelevant features, enabling more accurate feature map weights. We demonstrated the improved predictive value, with a multi-channel fusion network integrated with an attention mechanism, for overall survival of OPC patients.

Pilot Study of a Novel Ring Gantry-Based PET/CT Linear Accelerator in Patients with Prostate Cancer Receiving [18F]-DCFPyL for PSMA PET Imaging

PURPOSE/OBJECTIVE(S)

The RefleXion X1® system is a hybrid PET imaging-radiotherapy system that uses real-time positron emissions from a PET tracer to deliver biologically guided radiotherapy (BgRT). This study (NCT05470699) evaluated the hypothesis that the X1 PET imaging subsystem would be able to detect [18F]-DCFPyL PSMA PET signal sufficient to generate a deliverable BgRT plan in patients with prostate cancer.

MATERIALS/METHODS

Patients with prostate cancer scheduled for a diagnostic [18F]-DCFPyL PSMA PET scan as part of standard of care were eligible. Upon completion of the diagnostic PSMA PET scan, images were transferred to the radiotherapy planning system for target identification and contouring. If at least one PET avid tumor lesion was identified, the patient was then scanned on the X1 unit. BgRT planning was performed on each X1 scanned patient. The target lesion volume, activity concentration (AC) and normalized target signal (NTS) were acquired. Successful and deliverable BgRT plans required that the target AC was ≥ 5 kBq/ml and NTS ≥ 2.7.

RESULTS

Twenty-six patients underwent [18F]-DCFPyL PET scans (13 with rising PSA after surgery or radiotherapy, 6 with known metastases and 7 with newly diagnosed high-risk prostate cancer). Median (range) PSA was 3.40 (0.04-122). In 16 patients a PET avid tumor was identified and contoured for planning (4 lymph nodes, 5 bone, 6 prostate gland, and 1 prostate bed). In 13 patients the target lesion was visualized on the X1 PET scan, while in 3 patients the target lesion was too close to the bladder to be clearly visualized. BgRT planning was feasible and met standard of care published SBRT organ dose constraints in 8 patients (3 prostate gland, 3 bone, 2 lymph nodes). BgRT planning was not feasible in 8 patients due to insufficient AC, low NTS or proximity of the target lesion to the PET avid bladder. The accompanying table compares median (range) target volume, AC and NTS for feasible versus not feasible plans.

CONCLUSION

This is the first study to investigate the feasibility of using [18F]-DCFPyL PET imaging for BgRT plan generation on the X1 system in patients with prostate cancer. Lesions that are relevant to radiotherapy of prostate cancer can be visualized including lymph node and bone metastases. A dedicated BgRT workflow with PSMA PET imaging on the X1 at 60 minutes post injection will result in higher target AC and will optimize BgRT planning. PET avid lesions < 1 cm or close to the bladder may make BgRT planning challenging. [18F]-DCFPyL-guided BgRT is technically feasible using the RefleXion X1. BgRT using targeted PET radiopharmaceuticals to biologically guide external beam radiotherapy represents a promising new dimension in radiation oncology and warrants further investigation.

[Risk factors for delayed gastric emptying after laparoscopic pancreaticoduodenectomy: a single-center experience of 1 000 cases]

Objective: To explore the causes and summarize the treatment experience for clinically relevant delayed gastric emptying(DGE) after laparoscopic pancreaticoduodenectomy(LPD). Methods: The clinical data of 1 000 patients who underwent LPD in the Department of Liver Transplantation and Hepatobiliary Surgery,Shandong Provincial Hospital Affiliated to Shandong First Medical University between March 2017 and September 2022 was retrospectively collected. There were 640 males and 360 females,with an age of (60.1±11.4)years(range: 13 to 93 years),and 590 patients were older than 60 years. Depending on the severity of DGE,patients were divided into a clinically relevant DGE group and a 0/A grade DGE group. The comparison between the two groups was performed by the χ2 test,Fisher's exact probability method,t test or the rank sum test,and the effects of various treatment strategies for clinically relevant DGE were evaluated. Results: LPD was conducted successfully in all 1 000 patients,with a surgical time of (344.8±103.6)minutes(range:160 to 450 minutes) and intraoperative blood loss (M(IQR)) of 100 (150) ml(range:50 to 1 000 ml). A total of 74 patients(7.4%) developed clinically relevant DGE. Compared to those in the 0/A grade DGE group,patients in the clinically relevant DGE group had a higher preoperative body mass index of ((24.9±3.5)kg/m2 vs. (23.9±3.3)kg/m2,t=-2.419,P=0.016),more postoperative bile leakage(51.4%(38/74) vs. 10.8%(100/926)),pancreatic fistula(59.5%(44/74) vs. 22.9%(212/926)),abdominal infection(74.3%(55/74) vs.14.6%(135/926)),and abdominal bleeding(43.2%(32/74) vs. 11.3%(105/926))(all P<0.05). Among these patients,10 cases(13.5%) received enteral nutrition treatment,22 cases(29.7%) received parenteral nutrition treatment,and 42 cases(56.8%) received a combination of enteral and parenteral nutrition treatment. The time for patients to return to a normal diet was 21(14)days (range: 8 to 85 days). Compared to those who received only enteral(23.5(27.0)days) or parenteral nutrition treatment(15.5(11.0)days),patients who received a combination of enteral and parenteral nutrition treatment(25.5(31.0)days) had a longer time to return to a normal diet (Z=20.019,P<0.01). Among the 60 patients who developed secondary DGE,48 cases(80.0%) received ultrasound-guided puncture and drainage treatment,while 12 cases(20.0%) only received anti-infection treatment. The patients in the non-puncture drainage group had a longer time to return to a normal diet than those in the puncture drainage group (26.5(12.5)days vs. 20.0(11.0)days, Z=-2.369,P=0.018). Conclusions: Patients with clinically relevant DGE after LPD had a higher proportion of postoperative complications such as pancreatic fistula,biliary fistula and abdominal infection. A combination of enteral and parenteral nutrition treatment is needed for patients with a long-term course of DGE."Smooth" drainage and ani-infectious therapy could contribute to the recovery of DGE.

Maintenance Therapy for Recurrent or Metastatic Cervical Cancer: A Multicenter, Cohort Study

PURPOSE/OBJECTIVE(S)

Maintenance therapy with alternative agents after chemotherapy was shown to improve the overall survival in some advanced cancers such as breast cancer, lung cancer, ovarian cancer and so on. However, maintenance therapy is not accepted as the standard treatment for recurrent/metastatic cervical cancer. Aim of this study is to elucidate the efficacy of maintenance therapy in cervical cancer and to explore the factors associated with the prognosis of recurrent or metastatic cervical cancer.

MATERIALS/METHODS

In this multicenter cohort study, we retrospectively collected patients with a diagnosis of either recurrent or stage IVB cervical cancer to receive first-line chemotherapy with or without maintenance therapy. Patients did not have disease progression with first-line chemotherapy and were divided into maintenance therapy group (Arm A) and conventional chemotherapy group (Arm B). Information on clinical characteristics, metastasis information, treatment outcome and survival of patients was collected using an electronic medical record system. The endpoints of the study were OS and PFS. Data were analyzed for general characteristics and survival using statistical software, and the results were considered statistically significant at P < 0.05.

RESULTS

Between January 2019 and July 2021, a total of 270 patients were enrolled from 6 institutions in China. 26 patients were excluded because of short treatment cycles (less than 3 cycles). Finally, a total of 66 patients in Arm A and 178 patients in Arm B were analyzed for survival. The addition of maintenance significantly prolonged overall survival. Overall survival at 3 year was 50.1% in Arm A and 27.8% in Arm B (median overall survival, ≥36 months vs. 22 months; P<0. 001). The median progression-free survival was 21 months in Arm A and 14 months in Arm B (P = 0.025). Univariate survival analysis showed that age, maintenance therapy, combined radiotherapy, and number of extra-pelvic metastases were associated with PFS. Further multifactorial analysis showed that maintenance therapy, combined radiotherapy, and number of extra-pelvic metastases were independent prognostic factors for patients with recurrent or metastatic cervical cancer.

CONCLUSION

The addition of maintenance therapy significantly prolonged overall survival as well as progression-free survival in patients with recurrent or metastatic cervical cancer and did not increase the incidence of serious adverse events. It is time to consider maintenance therapy as the standard treatment after conventional chemotherapy for recurrent or metastatic cervical cancer, rather than waiting for disease progression.

Dosimetric Plan Evaluation of Biology Guided Radiotherapy Using [18F]-DCFPyL PSMA Radiotracer in Patients with Prostate Cancer

PURPOSE/OBJECTIVE(S)

The X1 system represents a cutting-edge solution in radiotherapy delivery, with its capability to perform Biology Guided Radiotherapy (BgRT). The system utilizes real-time positron emission tomography (PET) signal as biological fiducials to provide tracked dose delivery and is initially available for use with [18F]-Fluorodeoxyglucose (FDG). The aim of this research study is to assess the quality of BgRT treatment plans for prostate cancer using patients' PSMA PET images obtained on the X1 system.

MATERIALS/METHODS

Sixteen patients with at least one PET-avid tumor identified on their whole-body diagnostic PSMA PET scan were selected. These patients were scanned on X1 following their diagnostic scan without additional radiotracer administration. Based on the X1 PET images, a BgRT plan was created for each patient, with the prescription dose determined by the location of treatment sites. The planning objectives of organs-at-risk (OARs) were established in accordance with the 2018 Timmerman guidelines. Target coverage objective was the dose covering 95% (D95%) of the planning target volume (PTV) to be higher than 100%. The following parameters were analyzed: PTV D95%, the minimal dose (Dmin) of gross tumor volume (GTV), plan maximum dose (Dmax), conformity index (CI), gradient index (GI), and maximum point dose (D0.03cc) to the nearest OARs. The X1 BgRT planning system also generated dose volume histogram (DVH) bounds, which model variations in BgRT delivery. The low boundary of GTV Dmin, representing the minimum GTV dose in the worst-case scenario, was recorded.

RESULTS

BgRT plans were created for all patients, except for one where the target signal was indistinguishable from the bladder. The prescription dose was 2700 cGy or 3000 cGy in 3 fractions for lymph node lesions, 2400 cGy to 3000 cGy in 3 fractions for bone metastasis, and 4500 cGy in 5 fractions for lesions in prostate. All plans met the dose constraints for OARs as per the Timmerman guidelines. The Dmax of all plans was 129.9% ± 6.9% (mean ± standard deviation). The PTV D95% and GTV Dmin were 101.7% ± 1.0% and 111.0% ± 7.6%, respectively. The low boundary of GTV Dmin was 95.9% ± 5.8%. The CI and GI were 1.22 ± 0.11 and 9.40 ± 2.12, respectively. The D0.03cc to nearest OARs was 84.6% ± 25.4%. The estimated treatment time was 699 ± 228 seconds.

CONCLUSION

This study is a pioneering effort to evaluate the quality of BgRT plans for prostate cancer patients using the [18F]-DCFPyL PSMA radiotracer. Our results showed that all BgRT plans met the planning objectives defined in the Timmerman protocol. BgRT with [18F]-DCFPyL represents a promising treatment modality for patients with prostate cancer. Further research is needed to validate this approach, including a comprehensive assessment of the dosimetric and tracking accuracy through physical measurements.

The Role of Radiotherapy in Patients with Refractory Hodgkin Lymphoma after Brentuximab Vedotin and -/or Immune Checkpoint Inhibitors

PURPOSE/OBJECTIVE(S)

Brentuximab vedotin (BV) and immune checkpoint inhibitors (ICIs) had important roles in the treatment of relapse or refractory (R/R) Hodgkin lymphoma (HL). Treatment of refractory disease after BV and -/or ICIs remains a challenge. This study was conducted to evaluate the efficacy and safety of radiotherapy for R/R HL after failure to BV or ICIs.

MATERIALS/METHODS

We retrospectively analyzed patients in two institutions with R/R HL who had failed after first-line therapy, and were refractory to BV or ICIs, and received radiotherapy (RT) thereafter. The overall response rate (ORR), duration of response (DOR), progression-free survival (PFS) and overall survival (OS) were analyzed.

RESULTS

A total of 19 patients were enrolled. First-line systemic therapy consisted of ABVD (84.2%), AVD + ICIs (10.5%) and BEACOPP (5.3%), respectively. After first-line therapy, 15 patients (78.9%) were refractory, and 4 patients (21.1%) relapsed. After diagnosis of R/R HL, 8 patients (42.1%) received BV, and 17 patients (89.5%) received ICIs. RT was delivered in all 19 patients who failed after BV or ICIs. In 16 efficacy-evaluable patients, the ORR and CR rate were 100% and 100%. The median DOR was 17.2 months (range, 7.9 to 46.7 months). 3 patients progressed at outside of the radiation field. The in-field-response rate was 100%. The 12-month PFS and OS were 84.4% and 100%, respectively. No patients were reported with sever adverse events.

CONCLUSION

This study concluded that radiotherapy was effective and safe for refractory HL after BV or ICIs. Further prospective studies were warranted.

Anatomy-Guided Deep Learning Model for Accurate and Robust Gross Tumor Volume Segmentation in Lung Cancer Radiation Therapy

PURPOSE/OBJECTIVE(S)

In lung cancer radiation therapy, clinicians must outline the gross tumor volume (GTV) precisely on the planning computed tomography (pCT) for accurate radiation dose delivery. However, due to the limited contrast between tumor and normal tissues in lung parenchyma, accurate delineation of tumor boundaries is difficult leading to large inter-observer variation. In this study, we develop an anatomy-guided lung GTV deep segmentation model using a training cohort of multi-center datasets. The quantitative segmentation performance is evaluated on an independent dataset, where the inter-observer delineation variation is also assessed.

MATERIALS/METHODS

We collected and curated four publicly available lung datasets with GTV annotations (Lung-PET-CT-Dx, LIDC-IDRI, NSCLC-Radiogenomics and RIDER-CT) for deep learning model development. A total of 871 CT scans of patients, who were diagnosed with T1-T4 NSCLC, were available for training after data curation. The GTV annotations of primary tumor were examined and edited by two experienced radiation oncologists following the RTOG 1106 protocol. An anatomy-guided deep learning model was proposed, which consisted two deep networks. The first deep network used CT scan as input and segmented 4 anatomic organs (airway, heart, pulmonary artery and pulmonary vein), while the second deep network took both CT scan and these pre-segmented 4 organs as input and segmented the lung GTV. With the help of anatomic priors from 4 pre-segmented organs, the second deep network could more easily locate the GTV. We used nnUNet as the deep segmentation network. For evaluation, we used NSCLC-Radiomics as the testing dataset, which contains 20 CT scans each annotated by 5 radiation oncologists. The auto-segmented GTV were compared against each of the manual GTV reference. Inter-observer variation was also assessed using the 5 manual GTV references.

RESULTS

The proposed anatomic-guided lung GTV segmentation model achieved a mean Dice score of 82.4% and 95% Hausdorff distance (HD95) of 6.9mm when averaged cross 20 patients and 5 GTV references (Table 1), which outperformed the basic deep GTV segmentation model by markedly reducing 19.4% HD95 error. The performance of proposed model was also comparable to the inter-observer variation (Dice score: 82.4% vs. 81.9%, HD95 6.9 vs. 6.4mm), indicating that our model had similar reproducibility as human observers.

CONCLUSION

We developed and tested an anatomy-guided deep learning model for segmenting GTV in NSCLC patients. The model achieves high quantitative segmentation performance, which is comparable to the human observer variation. It can be potentially used in radiotherapy practice to improve GTV delineation consistency and reduce workloads of radiation oncologists.

Exploration of Multiomic Profiles and Biomarkers as Predictors of Neoadjuvant Chemoradiotherapy Responsiveness in Esophageal Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

The current gold standard of care for resectable locally advanced esophageal cancer is neoadjuvant chemoradiotherapy (NCRT) followed by surgery. Given that only 30-40% of patients with esophageal squamous cell carcinoma (ESCC) achieved a pathologic complete response (pCR) following neoadjuvant chemoradiotherapy, it is critical to understand the biological basis of NCRT resistance in esophageal cancer and identify biomarkers for these patients in order to further personalize treatment plans. We aim to depict the biological landscape of ESCC responsiveness and resistance to neoadjuvant chemoradiotherapy.

MATERIALS/METHODS

Endoscopic biopsied specimens of the primary tumors and paired peripheral blood samples were obtained from 24 patients before neoadjuvant chemoradiotherapy and tested for whole exosome sequencing, RNA sequencing, and DIA mass spectrometry. Genomic data were analyzed for significantly mutated genes, copy number alterations, MSI, TMB, and mutational signatures. Transcriptomics and proteomics data were used to examine differentially activated pathways. GSEA and ActivePathways were used for the single omics level and joint multi-omics analysis, respectively. Tumor microenvironment (TME) characteristics were deconvoluted by xCell upon RNA-seq data. Treatment resistance biomarkers were identified and validated in a separate cohort using mIHC.

RESULTS

In the study cohort, 54% (13/24) of the patients achieved pCR. WES data suggested that FBXW7 was more frequently mutated in the pCR group (fisher test p-value = 0.029), and the most significant cytoband loss in the pCR group was 9p21.3 (qval = 0.001). Differences in TMB, MSI, and mutational signatures were not significant between groups. Combined transcriptomics and proteomics analysis revealed that type I interferon signaling pathways and RIG-I-like receptor signaling pathways(p<0.05) were enriched in non-pCR tumors. Esophageal cancer cohort RNA-seq data from TCGA verified the correlation between the genetic variances (FBXW7 mutation and 9p21.3 loss) and the decreased expression of type I interferon signaling pathway genes. In TME analysis, tolerogenic dendritic cells and exhausted T cell signatures were significantly enriched in non-pCR tumors, indicating an immunosuppressive status in treatment resistant patients. Based on proteomics PPI network and differential expression genes from RNA-seq data, a biomarker panel consisted of 12 proteins predictive of non-pCR tumors was identified: STAT1, EIF2AK2, MX1, BST2, TRIM21, SAMHD1, IFI44L, GBP1, PARP14, ISG15, IFIT3, and HLA-B. The expression of selected genes was validated by mIHC in an independent cohort.

CONCLUSION

Through a multiomics approach, we described the biological characteristics of ESCC with distinct responses to neoadjuvant chemoradiotherapy and proposed a panel of 12 proteins as predictive biomarkers for non-pCR patients.

[Spatial distribution of Oncomelania hupensis spread in Hubei Province from 2020 to 2022]

OBJECTIVE

To identify the spatial distribution pattern of Oncomelania hupensis spread in Hubei Province, so as to provide insights into precision O. hupensis snail control in the province.

METHODS

Data pertaining to emerging and reemerging snails were collected from Hubei Province from 2020 to 2022 to build a spatial database of O. hupensis snail spread. The spatial clustering of O. hupensis snail spread was identified using global and local spatial autocorrelation analyses, and the hot spots of snail spread were identified using kernel density estimation. In addition, the correlation between environments with snail spread and the distance from the Yangtze River was evaluated using nearest-neighbor analysis and Spearman correlation analysis.

RESULTS

O. hupensis snail spread mainly occurred along the Yangtze River and Jianghan Plain in Hubei Province from 2020 to 2022, with a total spread area of 4 320.63 hm2, including 1 230.77 hm2 emerging snail habitats and 3 089.87 hm2 reemerging snail habitats. Global spatial autocorrelation analysis showed spatial autocorrelation in the O. hupensis snail spread in Hubei Province in 2020 and 2021, appearing a spatial clustering pattern (Moran's I = 0.003 593 and 0.060 973, both P values < 0.05), and the mean density of spread snails showed spatial aggregation in Hubei Province in 2020 (Moran's I = 0.512 856, P < 0.05). Local spatial autocorrelation analysis showed that the high-high clustering areas of spread snails were mainly distributed in 50 settings of 10 counties (districts) in Hubei Province from 2020 to 2022, and the high-high clustering areas of the mean density of spread snails were predominantly found in 219 snail habitats in four counties of Jiangling, Honghu, Yangxin and Gong'an. Kernel density estimation showed that there were high-, secondary high- and medium-density hot spots in snail spread areas in Hubei Province from 2020 to 2022, which were distributed in Jingzhou District, Wuxue District, Honghu County and Huangzhou District, respectively. There were high- and medium-density hot spots in the mean density of spread snails, which were located in Jiangling County, Honghu County and Yangxin County, respectively. In addition, the snail spread areas negatively correlated with the distance from the Yangtze River (r = -0.108 9, P < 0.05).

CONCLUSIONS

There was spatial clustering of O. hupensis snail spread in Hubei Province from 2020 to 2022. The monitoring and control of O. hupensis snails require to be reinforced in the clustering areas, notably in inner embankments to prevent reemerging schistosomiasis.

[Comparison of 5-year follow-up outcomes between"one-stop"procedure and long-term oral anticoagulants after radiofrequency catheter ablation in patients with atrial fibrillation]

Objective: To compare the 5-year follow-up outcomes of radiofrequency catheter ablation (RFCA) combined with left atrial appendage closure (LAAC) and long-term oral anticoagulant (OAC) after RFCA in patients with atrial fibrillation. Methods: This retrospective cross-sectional study included patients with atrial fibrillation who underwent"one-stop"procedure in the First Affiliated Hospital of Ningbo University from September 2015 to December 2017 (RFCA+LAAC group). Baseline data of patients were collected. Propensity score matching at the ratio of 1∶1 was used to select patients with atrial fibrillation who took long-term OAC after RFCA (RFCA+OAC group). The maintenance rate of sinus rhythm and the incidence of adverse events during follow-up were compared between the two groups. Results: A total of 110 patients were enrolled in the RFCA+LAAC group and RFCA+OAC group, respectively. Age of patients was (67.4±8.8) years in RFCA+LAAC group, and there were 42 (38.2%) female patients. Age of patients was (67.3±7.9) years in RFCA+OAC group, and there were 47 (42.7%) female patients. The patients were followed up for mean of (5.3±1.1) years. There was no significant difference in the maintenance rate of sinus rhythm (log-rank: χ2=0.277, P=0.602) and incidence of ischemic stroke events (2.7% (3/110) vs. 4.5% (5/110), P=0.719) during follow-up between the two groups. The incidence of bleeding events (6.4% (7/110) vs. 18.2% (20/110), P=0.008) and major bleeding events (1.8% (2/110) vs. 8.2% (9/110), P=0.030) was significantly higher in the RFCA+OAC group than in the RFCA+LAAC group. Conclusion: There is no significant difference between RFCA+LAAC group and RFCA+OAC group in maintenance rate of sinus rhythm and incidence of ischemic stroke events. Patients in the RFCA+LAAC group have a lower risk of bleeding events compared to the RFCA+OAC group.

[One case of acute poisoning with stramonium]

This paper reported 1 case of poisoning caused by stramonium. Cases of Datura poisoning have been reported nationwide, Its effect on the central nervous system of patients is characterized by first excitation and then inhibition, clinical manifestations include decreased gland secretion, dilated pupils, and tachycardia, etc. Its poisoning mechanism is anticholinergic effect, the effect on Peripheral nervous system is to inhibit Parasympathetic nervous system. Hemoperfusion combined with neostigmine anticholinergic therapy at the early stage of poisoning can effectively improve the clinical symptoms of patients in a short time.

[Impact of different diagnostic criteria for assessing mild micro-hepatic encephalopathy in liver cirrhosis: an analysis based on a prospective, multicenter, real-world study]

Objective: To compare the differences in the prevalence of mild micro-hepatic encephalopathy (MHE) among patients with cirrhosis by using the psychometric hepatic encephalopathy score (PHES) and the Stroop smartphone application (Encephal App) test. Methods: This prospective, multi-center, real-world study was initiated by the National Clinical Medical Research Center for Infectious Diseases and the Portal Hypertension Alliance and registered with International ClinicalTrials.gov (NCT05140837). 354 cases of cirrhosis were enrolled in 19 hospitals across the country. PHES (including digital connection tests A and B, digital symbol tests, trajectory drawing tests, and serial management tests) and the Stroop test were conducted in all of them. PHES was differentiated using standard diagnostic criteria established by the two studies in China and South Korea. The Stroop test was evaluated based on the criteria of the research and development team. The impact of different diagnostic standards or methods on the incidence of MHE in patients with cirrhosis was analyzed. Data between groups were differentiated using the t-test, Mann-Whitney U test, and χ (2) test. A kappa test was used to compare the consistency between groups. Results: After PHES, the prevalence of MHE among 354 cases of cirrhosis was 78.53% and 15.25%, respectively, based on Chinese research standards and Korean research normal value standards. However, the prevalence of MHE was 56.78% based on the Stroop test, and the differences in pairwise comparisons among the three groups were statistically significant (kappa = -0.064, P < 0.001). Stratified analysis revealed that the MHE prevalence in three groups of patients with Child-Pugh classes A, B, and C was 74.14%, 83.33%, and 88.24%, respectively, according to the normal value standards of Chinese researchers, while the MHE prevalence rates in three groups of patients with Child-Pugh classes A, B, and C were 8.29%, 23.53%, and 38.24%, respectively, according to the normal value standards of Korean researchers. Furthermore, the prevalence rates of MHE in the three groups of patients with Child-Pugh grades A, B, and C were 52.68%, 58.82%, and 73.53%, respectively, according to the Stroop test standard. However, among the results of each diagnostic standard, the prevalence of MHE showed an increasing trend with an increasing Child-Pugh grade. Further comparison demonstrated that the scores obtained by the number connection test A and the number symbol test were consistent according to the normal value standards of the two studies in China and South Korea (Z = -0.982, -1.702; P = 0.326, 0.089), while the other three sub-tests had significant differences (P < 0.001). Conclusion: The prevalence rate of MHE in the cirrhotic population is high, but the prevalence of MHE obtained by using different diagnostic criteria or methods varies greatly. Therefore, in line with the current changes in demographics and disease spectrum, it is necessary to enroll a larger sample size of a healthy population as a control. Moreover, the establishment of more reliable diagnostic scoring criteria will serve as a basis for obtaining accurate MHE incidence and formulating diagnosis and treatment strategies in cirrhotic populations.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)]  ps and B_{Λ}=[102±63(stat)±67(syst)]  keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

[Study on sIgE distribution characteristics and the sensitization pattern of allergen in 1 161 patients with allergic diseases of respiratory tract in northwest China]

Objective: To explore the allergen map of patients with allergic diseases in northwest China, to investigate the distribution characteristics of serum specific Immunoglobulin E (sIgE) in different ages, genders, diseases and the sensitization patterns of allergens. Methods: This study is a cross-sectional study, a total of 1 161 patients with confirmed respiratory allergic diseases were selected retrospectively from outpatient or inpatient department of Gansu Provincial People's Hospital, Gansu Provincial Maternity and Child Care Hospital, General Hospital of Ningxia Medical University, Yinchuan Maternal and Child Health Care Hospital, Xijing Hospital, Air Force Military Medical University and Tumor Hospital of Inner Mongolia Autonomous Region from June 2019 to October 2022. HAIKE ALLEOS 2000 fluorescent magnetic particle chemiluminescence method was used to quantify their serum for 12 inhaled allergen-specific IgE. Chi square test or Fisher's exact test were used for comparison between count data groups (Bonferroni correction was used for further pairwise comparison in multiple groups, two-sided P<0.05/3=0.017 considered that the difference was statistically significant). Pearson correlation analysis was used for correlation of continuous numerical variables. Results: The positive detection rate of sIgE in 1 161 patients was 66.8%(776/1 161). The three highest positive rate of inhaled allergen were mugwort(599/1 161, 51.6%), French chrysanthemum(565/1 161, 48.7%) and dandelion(412/1 161, 35.5%). In different age groups, the highest positive rate of sIgE was 7-18 age group(379/513, 73.9%) while the lowest positive rate was 4-6 age group(222/370, 60.0%), the difference between groups was statistically significant(χ2=21.177, P<0.001). The sensitization peak of mugwort, French chrysanthemum, plantain, timothy, birch, dermatophagoides pteronyssinus, dermatophagoides farinae, cat epithelium, dog epithelium and German cockroach appeared in 7-18 age group. In different disease groups, the highest positive rate of sIgE was allergic rhinitis with asthma group (500/717, 69.7%) while the lowest positive rate was asthma group (76/144, 52.8%), the difference between groups was statistically significant(χ2=15.563, P<0.001). In different gender groups, the positive rate of sIgE in male (503/711, 70.7%) was higher than in female (273/450, 60.7%), the difference between groups was statistically significant(χ2=12.630, P<0.001). The multiple-sensitization rate was 86.9%(674/776) and the double-sensitization rate was 16.8%(130/776) in sIgE positive patients. Pearson correlation results showed that there was an extremely strong correlation between dandelion and French chrysanthemum(r=0.93,P<0.001). There was a strong correlation between mugwort and French chrysanthemum(r=0.64,P<0.001). In the co-sensitization analysis, the number of patients sensitized by mugwort, French chrysanthemum, dandelion, plantain and timothy accounted for 25.2%(170/674)of the total number of multiple sensitization. The number of patients sensitized by mugwort, French chrysanthemum and dandelion accounted for 58.3%(393/674)of the total number of multiple sensitization. The number of patients sensitized by mugwort, French chrysanthemum, dandelion and plantain accounted for 35.6%(240/674) of the total number of multiple sensitization. Conclusion: Mugwort, French chrysanthemum, dandelion are the major inhaled allergens in northwest China. The positive rate of sIgE was different in different ages, diseases and genders. The multiple-sensitization rate of allergen was high and there was a certain positive correlation between pollen allergen-specific IgE pairwise, suggesting that there may exist co-sensitization or cross-reactions among allergens.

Impact of Bariatric Surgery on Cardiac Function and Structure in Chinese Patients with Obesity

Introduction: Obesity contributes to cardiac dysfunction and has an impact on atherosclerotic cardiovascular disease. Bariatric surgery (BS) is being considered a therapeutic option for patients with obesity and also can improve cardiac function. Very few studies considered the Chinese population. This study aimed to examine the effect of BS on cardiac function and structure in Chinese subjects with obesity. Methods: A single-center retrospective analysis of 143 patients with obesity was included. To observe and analyze the short-term, midterm, and long-term effects of BS on cardiovascular function and structure, the study population was divided into three groups according to the time of review. Fifty-two patients in group T1 (re-examination within 12 months); 53 patients in group T2 (re-examination within 12 to 24 months); and 38 patients in group T3 (re-examination over 24 months). The effects of BS on the cardiac function and structure were evaluated by analyzing the echocardiographic parameters. Results: After BS, body mass index (BMI) decreased from 39.7 ± 8.0 to 28.4 ± 6.4 kg/m2 (P < 0.001). Blood pressure decreased significantly. Left ventricular mass index (LVMI) decreased (43.7 ± 16.4 to 37.8 ± 13.4 g/m2.7, P < 0.001). The change in LVMI was correlated with the change in BMI (R2 = 0.14, P < 0.001). In subgroup analyses at different follow-ups, echocardiographic parameters showed varying degrees of change compared with the baseline. Conclusions: Significant weight loss by BS was associated with improved left ventricular structure and function in Chinese patients with obesity, suggesting potential favorable effects of BS on the cardiac function and structure.

First Measurement of the Nuclear-Recoil Ionization Yield in Silicon at 100 eV

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

Direct contact with endothelial cells drives dental pulp stem cells toward smooth muscle cells differentiation via TGF-β1 secretion

AIM

Prevascularization is vital to accelerate functional blood circulation establishment in transplanted engineered tissue constructs. Mesenchymal stem cells (MSCs) or mural cells could promote the survival of implanted endothelial cells (ECs) and enhance the stabilization of newly formed blood vessels. However, the dynamic cell-cell interactions between MSCs, mural cells and ECs in the angiogenic processes remain unclear. This study aimed to explore the interactions of human umbilical vein ECs (HUVECs) and dental pulp stem cells (DPSCs) in an in vitro cell coculture model.

METHODOLOGY

Human umbilical vascular ECs and DPSCs were directly cocultured or indirectly cocultured with transwell inserts in endothelial basal media-2 (EBM-2) supplemented with 5% FBS for 6 days. Expression of SMC-specific markers in DPSCs monoculture and HUVEC+DPSC cocultures was assessed by western blot and immunofluorescence. Activin A and transforming growth factor-beta 1 (TGF-β1) in conditioned media (CM) of HUVECs monoculture (E-CM), DPSCs monoculture (D-CM) and HUVEC+DPSC cocultures (E+D-CM) were analysed by enzyme-linked immunosorbent assay. TGF-β RI kinase inhibitor VI, SB431542, was used to block TGF-β1/ALK5 signalling in DPSCs.

RESULTS

The expression of SMC-specific markers, α-SMA, SM22α and Calponin, were markedly increased in HUVEC+DPSC direct cocultures compared to that in DPSCs monoculture, while no differences were demonstrated between HUVEC+DPSC indirect cocultures and DPSCs monoculture. E+D-CM significantly upregulated the expression of SMC-specific markers in DPSCs compared to E-CM and D-CM. Activin A and TGF-β1 were considerably higher in E+D-CM than that in D-CM, with upregulated Smad2 phosphorylation in HUVEC+DPSC cocultures. Treatment with activin A did not change the expression of SMC-specific markers in DPSCs, while treatment with TGF-β1 significantly enhanced these markers' expression in DPSCs. In addition, blocking TGF-β1/ALK5 signalling inhibited the expression of α-SMA, SM22α and Calponin in DPSCs.

CONCLUSIONS

TGF-β1 was responsible for DPSC differentiation into SMCs in HUVEC+DPSC cocultures, and TGF-β1/ALK5 signalling pathway played a vital role in this process.