BACKGROUND:Skin damage caused by radiation therapy and nuclear accidents is still a serious medical problem.It is difficult to achieve effective treatment results with single prevention and treatment methods.It is an important research direction to find new comprehensive treatment methods. OBJECTIVE:To observe the protective effect and the underlying mechanism of 1,2-propanediol combined with hepatocyte growth factor-modified exosomes derived from dental pulp stem cells on human epidermal radiation damage cell models. METHODS:(1)After infection of human dental pulp stem cells using recombinant adenovirus of human hepatocyte growth factor gene,exosomes,i.e.,Ad.HGF DPSC-Exo,were isolated with ultracentrifugation.(2)HaCat cells were irradiated with X-ray.The cells were treated with 1,2-propanediol before irradiation and Ad.HGF DPSC-Exo after irradiation.Cell proliferative activity was determined by CCK-8 assay.Cell apoptosis was detected by flow cytometry.Cell migration was detected by cell scratch assay.The expression levels of P21 and P53 were detected by PCR. RESULTS AND CONCLUSION:1,2-Propanediol,Ad.HGF.DPSC-Exo,Ad.HGF.DPSC-Exo + 1,2-propanediol could significantly improve the growth inhibition of HaCaT cells,reduce cell apoptosis,elevate cell proliferation and migration,and exhibit a good radiation protection effect.Moreover,the combined effect of Ad.HGF.DPSC-Exo + 1,2-propanediol was better.Furthermore,Ad.HGF.DPSC-Exo + 1,2-propanediol alleviated the cellular G2/M phase block and decreased the expression of cell cycle genes P53 and P21.In conclusion,1,2-propanediol pretreatment combined with Ad.HGF.DPSC-Exo had significant protective effects on radiation-induced HaCaT cell injury and it provided novel ideas and potential methods for the prevention and treatment of radiation-induced skin damage.

Objective To evaluate the therapeutic effect of poloxamer hydrogel loaded with exosomes derived from human dental pulp stem cells genetically modified with human hepatocyte growth factor against radiation skin injuries.Methods Human dental pulp stem cells derived exosomes(DPSC-Exo)and hepatocyte growth factor modified DPSC-Exo(HGF-DPSC-Exo)were extracted via ultracentrifugation separation,identified in terms of particle size and morphology,and analyzed separately by means of nanoparticle tracking analysis and scanning electron microscopy(SEM),while exosome marker proteins were determined by Western blot.Then,the effect of exosomes on radiation-damaged skin cells was assessed.The poloxamer hydrogel was prepared and its safety was evaluated with CCK-8.A mouse model of injury combined with radiation injury was established,and the therapeutic effect of hydrogel loaded with exosomes was determined based on wound size,HE and Masson staining.Furthermore,the underlining therapeutic mechanism was explored with Tunnel assay,malondialdehyde content and peroxidase activity.Results The diameter exosomes ranged from 30 to 150 nm and their morphology was a disc-shaped vesicle under SEM.Moreover,CD9,CD63 and TSG101 were expressed.The results of cellular experiments showed that exosomes significantly promoted the proliferation and migration of radiation-damaged skin keratinocytes and fibroblasts,and reduced their apoptosis.HGF modification enhanced the healing effect of exosomes.Poloxamer hydrogel showed good temperature-sensitive properties and biocompatibility.The results of animal experiments showed that exosomes significantly accelerated the healing of radiation-combined injuries in mice,inhibited inflammatory infiltration and mitigated collagen deposition in the wound.Interestingly,the healing effect in the group treated with hydrogel loaded with exosomes was the best.The underlining mechanism was possibly related to promotion of cell proliferation and inhibition of apoptosis and oxidative stress.Conclusion A novel poloxamer hydrogel loaded HGF-DPSC-Exo has been prepared and its therapeutic effect against radiation combined injury has been proved,thus providing a new strategy for the treatment of radiation skin injury in clinic.

Objective:To evaluate the effects of different imaging frequencies and matching strategies of cone-beam computed tomography (CBCT) on dose-volume parameters in target and organs at risk (OAR) during image-guided radiotherapy for prostate cancer.Methods:A total of 561 sets of CBCT images from 21 patients treated with radical prostate radiotherapy who were admitted to Peking University First Hospital from June 2022 to May 2023 were retrospectively analyzed. All patients received volumetric intensity modulated arc therapy (VMAT) at a prescribed dose of 70 Gy divided into 25 times, 2.8 Gy per time. Clinical target volume (CTV) and OAR were delineated by the same oncologist on each CBCT image. The planned CT (pCT) was rigorously registered to CBCT after calibration of positioning errors according to different image guidance modes and frequencies, and CT values and structures were propagated to CBCT through deformable image registration (DIR). The daily dose was mapped to pCT according to the deformation vector field (DVF) for dose accumulation. The actual cumulative dose of daily online CBCT validation was compared with the weekly CBCT validation regimen (days 1, 2, 3, 6, 11, 16 and 21 online imaging). The dosimetric comparison was also made between bone-based matching and soft tissue-based matching (after automatic bone-based matching, manual prostate-based matching was performed and fine-tuning was made regarding the anterior wall of rectum). Wilcoxon signed rank-sum test was utilized to analyze dose-volume parameters between planned and cumulative doses that exhibited non-normal distribution, while paired t-test was employed for assessing shift values and average dose parameters that demonstrated normal distribution. Results:Compared with daily CBCT image guidance, the CTV_D 98% in weekly CBCT was significantly reduced [(69.08±1.58) vs. (65.24±3.64) Gy, P<0.001]. The CTV_D 98% of bone-based matching was (69.27±2.14) Gy, but the high-dose volume of the rectum were significantly increased: V 60 Gy was 3.18%±3.10%, V 65 Gy was 0.77%±1.23%. The target area coverage using soft tissue-based matching is sufficient, with a CTV_D 98% of (69.08±1.58) Gy. And the percentage volume of high-dose volume of the rectum was significantly reduced, with V 60 Gy being 2.02%±2.42% and V 65 Gy being 0.34%±0.68%. Conclusions:In prostate cancer patients undergoing moderately-fractionated radiotherapy, daily CBCT image guidance demonstrates superior target coverage compared to a weekly scheme. Soft tissue-based matching, which is automatic bone-based matching followed by manual soft tissue-based matching and fine-tuning according to the anterior rectal wall, offers better rectal protection while maintaining target coverage.

Hepatocellular carcinoma(HCC)is one of the most common tumor types and remains a major clinical challenge.Increasing evidence has revealed that mitophagy inhibitors can enhance the effect of chemotherapy on HCC.However,few mitophagy inhibitors have been approved for clinical use in humans.Pyrimethamine(Pyr)is used to treat infections caused by protozoan parasites.Recent studies have reported that Pyr may be beneficial in the treatment of various tumors.However,its mechanism of action is still not clearly defined.Here,we found that blocking mitophagy sensitized cells to Pyr-induced apoptosis.Mechanistically,Pyr potently induced the accumulation of autophagosomes by inhibiting autophagosome-lysosome fusion in human HCC cells.In vitro and in vivo studies revealed that Pyr blocked autophagosome-lysosome fusion by upregulating BNIP3 to inhibit synaptosomal-associated protein 29(SNAP29)-vesicle-associated membrane protein 8(VAMP8)interaction.Moreover,Pyr acted synergistically with sorafenib(Sora)to induce apoptosis and inhibit HCC proliferation in vitro and in vivo.Pyr enhances the sensitivity of HCC cells to Sora,a common chemotherapeutic,by inhibiting mitophagy.Thus,these results provide new insights into the mechanism of action of Pyr and imply that Pyr could potentially be further developed as a novel mitophagy inhibitor.Notably,Pyr and Sora combination therapy could be a promising treatment for malignant HCC.

Objective:To investigate the advantage of three dimensional(3D)-printed tissue compensators in radiotherapy for superficial tumors at irregular sites.Methods:A subcutaneous xenograft model of prostate cancer in nude mice was established. Mice were randomly divided into no tissue compensator group( n=6), common tissue compensator group( n=6), and 3D-printed tissue compensator group( n=6). Computed tomography (CT) images of nude mice in the 3D-printed tissue compensator group were acquired. Compensator models were made using polylactic acid, and material properties were evaluated by measuring electron density. CT positioning images of the three groups after covering the corresponding tissue compensators were acquired to delineate the gross tumor volume (GTV). Nude mice in the three groups were irradiated with 6 MV X-rays at the prescribed dose. The prescribed dose for the three groups was 1 500 cGy. The dose distribution in the GTV of the three groups was calculated and compared using the analytical anisotropic algorithm in the Eclipse 13.5 treatment planning system. The metal-oxide-semiconductor field-effect transistor was used to verify the actual dose received on the skin surface of nude mice. Results:The air gap in the 3D-printed tissue compensator group and the common tissue compensator group was 0.20±0.07 and 0.37±0.07 cm 3, respectively ( t=4.02, P<0.01). For the no tissue compensator group, common tissue compensator group, and 3D-printed tissue compensator group, the D95% in the target volume was (1 188.58±92.21), (1 369.90±146.23), and (1 440.29±45.78) cGy, respectively ( F=9.49, P<0.01). D98% was (1 080.13±88.30), (1 302.76±158.43), and (1 360.23±48.71) cGy, respectively ( F=11.17, P<0.01). Dmean was (1 549.08±44.22), (1 593.05±65.40), and (1 638.87±40.83) cGy, respectively ( F=4.59, P<0.05). The measured superficial dose was (626.03±26.75), (1 259.83±71.94), and (1 435.30±67.22) cGy, respectively ( F=263.20, P<0.001). The percentage variation in tumor volume growth after radiation was not significantly different between the common tissue compensator group and the 3D-printed tissue compensator group ( P>0.05). Conclusions:3D-printed tissue compensators fit well to the body surface, which reduces air gaps, effectively increases the dose on the body surface near the target volume, and provides ideas for radiotherapy for superficial tumors at some irregular sites.

Objective:To compare the efficacy and safety of standard treatment with or without adjuvant chemotherapy in patients with highly malignant non-metastatic prostate cancer.Methods:In this prospective non-randomized controlled study, consecutive non-metastatic prostate cancer patients with pathologically proven Gleason score of 9-10 or Gleason score of 5 admitted to Peking University First Hospital were enrolled. Four to six cycles of chemotherapy using docetaxel ± carboplatin regimen were added or not after standard radical therapy. The primary end point was 5-year event-free survival (EFS), and the secondary end points were distant metastasis-free survival (MFS), overall survival (OS), and treatment-related adverse events. The survival curve was drawn by Kaplan-Meier method. The differences between two groups were analyzed by log-rank test.Results:A total of 176 patients were consecutively enrolled from November 2019 to January 2022 of which 138 patients received only standard radical therapy (control group), and 38 patients received adjuvant chemotherapy after standard radical therapy (chemotherapy group). The median follow-up time was 13.4 (2.0-34.0) months. All patients survived. The 30-month EFS rates in the chemotherapy and control groups were 100% and 85.6%, respectively ( P=0.064). There were no events in the chemotherapy group, while there were 12 cases of events in the control group, including 6 cases of biochemical recurrence and 6 cases of imaging progression. The 30-month MFS rates in two groups were 100% and 91.9%, respectively ( P=0.205). After the 1 vs. 2 propensity score matching, the EFS and MFS rates in two groups were 100% vs. 85.7% ( P=0.056), and 100% vs. 92.2% ( P=0.209), respectively. The incidence rates of grade 2 and above urinary toxicity in the chemotherapy and control groups were 2.6% and 7.2% ( P=0.354), respectively. The incidence rates of grade 2 and above rectal toxicity were 5.3% and 5.1% ( P=0.711), respectively. Grade 3 and above chemotherapy-related toxicity in the chemotherapy group were leukopenia (31.6%), thrombocytopenia (2.6%) and alopecia (13.2%). Conclusion:The addition of adjuvant chemotherapy after standard radical therapy tends to improve the overall EFS of patients with highly malignant prostate cancer, and the adverse effects are tolerable, which should be confirmed by long-term follow-up results.

ObjectiveTo investigate the effects of Yishen Daluo prescription （YSDL） on Ras homolog（Rho）/Rho-associated coiled-coil containing protein kinase（ROCK）signaling pathway in mice with experimental autoimmune encephalomyelitis （EAE） based on the silencing of β-arrestin1 gene. MethodSixty C57BL/6 female mice were randomly divided into a blank group， a model group， a virus group， a YSDL group， a virus + YSDL group， and a prednisone acetate group （hormone group）. The EAE model was induced in mice except for those in the normal group. Adeno-associated virus（AAV）solution （150 μL， 1×10¹¹ vg·mL^-1） was injected into the tail vein of each mouse in the virus group and the virus + YSDL group on the 4^th day of immunization. Drugs were administered on the 8^th day of modeling. Specifically， normal saline was given to the mice in the normal group，the model group，and the virus group at 10 mL∙kg^-1， prednisone acetate suspension to those in the hormone group at 3.9 g∙kg^-1，and YSDL to those in other groups at 20 g∙kg^-1 for 14 consecutive days. The mice were weighed and scored every day. The neurological function scores of mice in each group were recorded every day after immunization. Hematoxylin-eosin （HE） staining was used to determine the inflammatory response and lesion location in the brain tissues and spinal cord tissues of mice. The protein expression of β-arrestin1，Ras homolog gene family member A（RhoA）， and Rho-associated coiled-coil forming protein kinase Ⅰ（ROCK Ⅰ） in spinal cord and brain tissues of EAE mice was determined by Western blot. ResultCompared with the model group， the virus group and the virus + YSDL group showed decreased neurological function scores （P<0.01），and the YSDL group also showed decreased neurological function scores（P<0.05）. HE results showed that there was obvious inflammatory reaction in the central nervous system （CNS） of the model group， which was alleviated to varying degrees in other groups compared with the model group. Western blot results showed that compared with the blank group， the model group showed increased protein expression levels of β-arrestin1， RhoA， and ROCK Ⅰ in the spinal cord tissues （P<0.01）. Compared with the model group， the virus group， the YSDL group， the virus + YSDL group， and the hormone group showed decreased protein expression levels of β-arrestin1， RhoA， and ROCKⅠ in the spinal cord tissues （P<0.01）. Compared with the blank group， the model group showed increased protein expression levels of β-arrestin1， RhoA， and ROCK Ⅰ in the brain tissues （P<0.01）. Compared with the model group， the virus group， the YSDL group， the virus + YSDL group， and the hormone group showed decreased protein expression level of β-arrestin1 in the brain tissues （P<0.01）， and the virus group and the YSDL group showed decreased protein expression levels of RhoA， and ROCKⅠ in the brain tissues （P<0.05）. Additionally， the virus + YSDL group and the hormone group showed decreased protein expression levels of RhoA and ROCKⅠ in the brain tissues （P<0.01）. ConclusionYSDL can improve the clinical symptoms of EAE mice and improve the inflammatory response of CNS. The mechanism is presumably attributed to the fact that YSDL inhibits the expression of β-arrestin1 in CNS，thereby reducing the expression of Rho/ROCK signaling pathway. Furthermore， YSDL may have a synergistic effect with the inhibition of β-arrestin1 gene expression.

Objective:Partial stereotactic ablative boost radiotherapy(P-SABR)is a method to deliver SABR boost to the gross tumor boost volume(GTVb), followed by conventionally fractionated radiotherapy to the whole tumor area(GTV). GTVb is the max volume receiving SABR while ensuring the critical organ-at-risk(OAR)falloff to 3 GyE/f. We investigated the potential advantage of proton therapy in treating bulky non-small cell lung cancer(the tumor length greater than 8 cm).Methods:Nine patients with bulky NSCLC treated with photon P-SABR in our institute were selected. For the treatment planning of proton therapy, the GTVb target area was gradually outwardly expanded based on the photon GTVb target area until the dose to critical OARs reached 3 GyE/f. The GTV and CTV areas remained the same as photon plan. A proton intensity-modulated radiation treatment plan(proton-IMPT), a photon intensity-modulated radiation treatment plan(photon-IMRT)and a photon volumetric modulated arc therapy(photon-VMAT)were created for each patient, respectively. The dosimetric parameters of different treatment plans were compared.Results:The volume ratio of GTVb-photon and GTVb-proton to GTV was(25.4±13.4)% and(69.7±30.0)%,respectively( P<0.001). In photon-IMRT, photon-VMAT, and proton-IMPT plan groups, the mean dose of CTV was(76.1±4.9)Gy, (78.2±3.6)Gy, and(84.7±4.9)Gy, respectively; the ratio of tumor volume with Biologic Effective Dose(BED)≥ 90 Gy to GTV volume was(70.7±21.7)%, (76.8±22.1)%,and(97.9±4.0)%,respectively. The actual dose and BED to the tumor area of the proton-IMPT plan group were significantly higher than those of the photon plan group(both P<0.05). Besides, the OARs dose was significantly decreased in the proton-IMPT group, with(49.2±22.0)%, (56.8±19.0)% and(16.1±6.3)% of the whole lung V5 for photon-IMRT, photon-VMAT and proton-IMPT, respectively(all P<0.001). Conclusions:Larger GTV boost target volume, higher BED and reduced OARs dose can be achieved in proton plans compared with photon plans. Proton P-SABR is expected to further improve the local control rate of bulky NSCLC with fewer adverse effects.

Objective:To investigate the efficacy and safety of radiotherapy for all metastases in patients with metachronous oligo-metastatic prostate cancer after radical treatment.Methods:From October 2011 to February 2021, 41 patients with prostate cancer with less than 5 metastases after radical treatment were retrospectively analyzed in a single center. The median age at radiotherapy was 68 (57-81) years. Forty patients (98%) received androgen deprivation therapy (ADT). There were 28 patients in the hormone sensitive (HSPC) group and 13 patients in the hormone resistant (CRPC) group. The median initial PSA was 24.4 (7.4-399.0) ng/ml. Tumor stage: T 2 stage 11 patients, T 3 stage 27 patients, T 4 stage 3 patients.30 patients were in N 0 stage and 11 patients in N 1 stage. Gleason score was 7 in 12 patients, 8 in 9 patients, 9 in 18 patients, and 10 in 2 patients.33 patients were treated with surgery, and 8 patients were treated with radiotherapy. The time span from diagnosis to metastasis was 3.1 (0.2-1.8) years. Conventional imaging examination (CT/ MRI/bone scan) before radiotherapy was used in 7 patients, and PSMA PET/CT examination was used in 34 patients.The median PSA before radiotherapy was 1.3(0.1-33.8) ng/ml. There were 62 metastases in 41 patients, including 1 lesion in 28 patients, 2 lesions in 9 patients, 3 lesions in 2 patients, and 5 lesions in 2 patients. Fifty-four patients had bone metastases and eight had retroperitoneal lymph node metastases. Twenty-two bone metastases were located in the pelvis, 18 in the vertebral body, 12 in the ribs, one in the femur and one in the sternum.The median metastatic volume was 5.8(0.2-81.7) cm 3.Daily image-guided rotational intensity modulated radiotherapy was used to cover all metastases.Dose segmentation modes include 37.5Gy/7.5Gy/5F, 60Gy/3Gy/20F, 65-70Gy/2.6-2.8Gy/25F.The median biological effective dose (BED 3) was 120 (67-147) Gy. The primary endpoint was biochemical progression-free survival (BPFS), the secondary endpoints were acute and late toxic side effects, local relapse-free survival (LPFS), and overall survival (OS). Results:The median follow-up time was 21 months (range 5-72 months). All patients completed radiotherapy, and 16 patients had grade 1 to 2 acute toxicity and side effects, and no grade 3 or above acute and late stage side effects. 1-year LPFS was 97.1%.The 1-year and 2-year BPFS were 77.5% and 59.2%, respectively. The median BPFS time was 29 months (range 13.9-44.2 months). Univariate analysis showed that the HSPC group ( P<0.001) and the group with total metastatic volume ≤ 5.8cm 3 ( P=0.010) had higher BPFS. The median BPFS time was 37 months in the retroperitoneal lymph node metastases subgroup and 17 months in the bone metastases subgroup ( P=0.141). In the HSPC group, the median BPFS was 30(22-38) months. After radiotherapy, PSA decreased in all 28 patients, and increased in 6 patients. The median BPFS was 12(4-18) months. In the CRPC group, the median BPFS was 4(0-8) months. PSA decreased in 10 patients (76.9%) after radiotherapy, and PSA decreased in 6 patients. The median BPFS was 5(3-28) months. Three patients’PSA did not decrease after radiotherapy, and they were treated with new endocrine therapy drugs, chemotherapy, immunotherapy and other systemic therapy. Conclusions:For patients with metachronous metastases after radical treatment, full coverage radiotherapy has good safety and high local control rate. HSPC patients and patients with low tumor load could be recommended to receive radiotherapy for all metastatic lesions preferentially, and patients with only retroperitoneal lymph node metastases may have better prognosis after radiotherapy than patients with bone metastases.

Objective: To compare the efficiency between the transhepatic hilar approach and conventional approach for the surgical treatment of Bismuth type Ⅲ and Ⅳ hilar cholangiocarcinoma. Methods: There were 42 consecutive patients with hilar cholangiocarcinoma of Bismuth type Ⅲ and Ⅳ who underwent surgical treatment at Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University from January 2008 to December 2013.The transhepatic hilar approach was used in 19 patients and conventional approach was performed in 23 patients.There were no differences in clinical parameters between the two groups(all P>0.05). The t-test was used to analyze the measurement data, and the χ² test was used to analyze the count data.Kaplan-Meier analysis was used to analyze the survival period.Multivariate COX regression analysis was used to analyze the prognosis factors. Results: Among the 19 patients who underwent transhepatic hilar approach, 3 patients changed the operative planning after reevaluated by exposing the hepatic hilus.The intraoperative blood was 300(250-400)ml in the transhepatic hilar approach group, which was significantly less than the conventional approach group, 800(450-1 300)ml(t=4.276, P=0.00 1), meanwhile, the R0 resection rate was significantly higher in the transhepatic hilar approach group than in the conventional approach group(89.4% vs. 52.2; χ²=6.773, P=0.009) and the 3-year and 5-year cumulative survival rate was better in the transhepatic hilar approach group than in the conventional approach group(63.2% vs. 47.8%, 26.3% vs. 0; χ²=66.363, 127.185, P=0.000). On univariate analysis, transhepatic hilar approach, intraoperative blood loss, intraoperative blood transfusion, R0 resection and lymph node metastasis were significant risk factors for patient survival(all P<0.05). On multivariate analysis, use of transhepatic hilar approach, intraoperative blood loss, R0 resection and lymph node metastasis were significant independent risk factors for patient survival(all P<0.05). Conclusion The transhepatic hilar approach is the preferred technique for surgical treatment for hilar cholangiocarcinoma because it can improve accuracy of surgical planning, safety of operation, R0 resection rate and survival rate compared with the conventional approach.