AIM:To explore the role of miR-195-5p in mediating trastuzumab resistance in gastric cancer and to validate its potential as a therapeutic target along with its target gene GPRC5A.METH-ODS:Trastuzumab-resistant gastric cancer cell lines(NCI-N87 and MKN45)were established.Cell viabili-ty under trastuzumab treatment was assessed us-ing CCK-8 assays.Expression levels of miR-195-5p were determined by RT-qPCR.Transfection with miR-195-5p mimics was performed to evaluate changes in trastuzumab sensitivity and prolifera-tion.GPRC5A expression was also measured by RT-qPCR,and the targeting relationship between miR-195-5p and GPRC5A was confirmed using a dual-lu-ciferase reporter assay.RESULTS:Parental cells showed higher sensitivity to trastuzumab than re-sistant cells,with miR-195-5p expression signifi-cantly lower in the latter.Overexpression of miR-195-5p in resistant cells enhanced trastuzumab sen-sitivity and reduced proliferation.GPRC5A was found to be upregulated in resistant cells,and miR-195-5p directly targeted GPRC5A,affecting cell pro-liferation under trastuzumab treatment.CONCLU-SION:miR-195-5p may regulate trastuzumab sensi-tivity in gastric cancer by targeting GPRC5A,sug-gesting potential as a molecular marker for trastu-zumab therapy guidance.

AIM:To explore the role of miR-195-5p in mediating trastuzumab resistance in gastric cancer and to validate its potential as a therapeutic target along with its target gene GPRC5A.METH-ODS:Trastuzumab-resistant gastric cancer cell lines(NCI-N87 and MKN45)were established.Cell viabili-ty under trastuzumab treatment was assessed us-ing CCK-8 assays.Expression levels of miR-195-5p were determined by RT-qPCR.Transfection with miR-195-5p mimics was performed to evaluate changes in trastuzumab sensitivity and prolifera-tion.GPRC5A expression was also measured by RT-qPCR,and the targeting relationship between miR-195-5p and GPRC5A was confirmed using a dual-lu-ciferase reporter assay.RESULTS:Parental cells showed higher sensitivity to trastuzumab than re-sistant cells,with miR-195-5p expression signifi-cantly lower in the latter.Overexpression of miR-195-5p in resistant cells enhanced trastuzumab sen-sitivity and reduced proliferation.GPRC5A was found to be upregulated in resistant cells,and miR-195-5p directly targeted GPRC5A,affecting cell pro-liferation under trastuzumab treatment.CONCLU-SION:miR-195-5p may regulate trastuzumab sensi-tivity in gastric cancer by targeting GPRC5A,sug-gesting potential as a molecular marker for trastu-zumab therapy guidance.

Objective:To explore the changes of left atrial volume and function in patients with early diabetic nephropathy by four-dimensional auto left atrial quantification (4D Auto LAQ).Methods:Forty patients with early diabetic nephropathy (early diabetic nephropathy group), 40 patients with type 2 diabetes (diabetes group) in Henan Provincial People′s Hospital from March 2020 to April 2021 were selected, and 36 healthy volunteers (control group) were collected during the same period. The parameters of conventional echocardiography were measured, and the four-dimensional volume probe was used to obtain the complete left atrial volume image in 5 cardiac cycles. The 4D Auto LAQ software on the EchoPAC workstation was used for analysis to obtain the left atrial volume and strain indicators: left atrial (LA) maximum volume (LAVmax), left atrial minimum volume (LAVmin), pre-systolic volume (LAVpreA), left atrial volume index (LAVImax), left atrial emptying volume (LAEV), left atrial emptying fraction (LAEF), and long axis and circumferential strains in left atrial reserve phase, pipeline phase and systolic phase (LASr, LASr-c; LAScd, LAScd-c; LASct, LASct-c). The differences of these parameters among 3 groups were analyzed.Results:There were no significant differences in interventricular septum end-diastolic thickness(IVSd), left ventricular posterior wall end-diastolic thickness(LVPWd), left ventricular end-diastolic dimension(LVIDd), left ventricular ejection fraction(LVEF), and E/A (ration of early to late diastolic peak flow velocity of mitral orifice) among 3 groups (all P>0.05), and left atrial diameter(LAD), relative wall thickness(RWT), and E/e′ (ration of early diastolic peak flow velocity of mitral orifice to early diastolic velocity of lateral mitral annulus) among 3 groups were significantly different (all P<0.05). Further pairwise comparison results showed that LAD was only significantly different between the early diabetic nephropathy group and control group ( P=0.001 2), and the differences in RWT and E/e′ were statistically significant among 3 groups (all P<0.05). There were no significant differences in LAEV, LAScd-c, and LASct-c among 3 groups (all P>0.05), and LAVmin, LAVmax, LAVpreA, LAVImax, LAEF, LASr, LAScd, LASct, and LASr-c among the 3 groups were significantly different (all P<0.05). The pairwise comparison showed that, compared with the control group and the diabetes group, LAVmin, AVpreA, and LAVImax in the early diabetic nephropathy group were increased, and LAEF, LAScd, LASct, and LASr-c were decreased (all P<0.05). Compared with the control group, LAVmax, LAVImax and LASct in the diabetes group were increased, and LAEF, LAScd, and LASr-c were decreased (all P<0.05). Conclusions:4D Auto LAQ technology can quantitatively evaluate the changes in left atrium volume and function in patients with early diabetic nephropathy. Patients with early diabetic nephropathy have an increase in left atrium volume and a decrease in strain value.

Objective:To investigate the effectiveness of abdominal compression in tumor motion and the target volume, and analyze the suitable margins of planning target volume (PTV) for patients treated with lung-SBRT based on 4DCT.Methods:Patients diagnosed with peripheral pulmonary tumor were enrolled. The patients were divided into the whole group, upper-middle-lobe group (group A) and the lower-lobe group (group B). Each patient underwent 3DCT, 4DCT with abdominal compression (4DCT com) and 4DCT with free breath (4DCT free) scans. The GTVs were delineated and IGTVs on these images. PTV MIP 5 mm, PTV MIP 4 mm, PTV MIP 3 mm were constructed with a 5, 4, 3 mm margin in left-right (LR), anterior-posterior (AP) directions and cranial-caudal (CC) directions. Results:The median motion vector with compression reduced by 30.92% in whole group, increased by 3.42% in group A and reduced by 18.80% in group B, respectively. And there were no significant differences of TMA LR, TMA AP, TMA CC and motion vector by the Wilcoxon test ( P>0.05). The median sizes of IGTV MIP com , IGTV MIP free and IGTV10 com, IGTV10 free were 4.01, 5.36 cm 3and 6.59, 7.65 cm 3, with statistically significant difference ( Z=-3.45, -3.14, P<0.01). The median ratio of DI of IGTV CBCT com in PTV MIP 5 mm, PTV MIP 4 mm and PTV MIP 3 mm≥95% was 100%, 100% and 83.33%, respectively. Conclusions:The patients′ respiratory pattern changed with abdominal compression and abdominal compression is useful in reducing the size of IGTV MIP and IGTV10, which could reduce the target volume and protect the normal tissue. Adding a 4 mm margin to IGTV MIP com based on 4DCT account for respiration in SBRT is a tendency for precise radiotherapy.

Objective:To observe the feasibility of magnetic resonance (MR)-guided stereotactic body radiotherapy (SBRT) for non-small cell lung cancer, and analyze the dosimetric differences in the presence or absence of magnetic field.Methods:Three patients with non-small cell lung cancer were prospectively treated with MR-guided linac (MR linac) for SBRT, and the dose was calculated with or without magnetic field models. The differences of dose distribution with or without magnetic field models were compared. At the same time, the target coverage, plan pass rate and treatment time were described, and the complexity of the conventional accelerator backup plan and the magnetic field model were compared.Results:The treatment time of 3 patients was (36.67±6.11) min, and the average time of online adaptive planning was (14.4±1.7) min, which was basically tolerated by patients. The treatment plan pass rate (3%/3 mm) was 98.9%, the Gamma pass rate (3%/3 mm) of the online plan during treatment was 98.5% and the target coverage was 99.1%, which met the clinical needs. The dose in the low dose area of the lung was slightly lower than that in the case without magnetic field, whereas the dose in ribs and skin was slightly higher than that in the plan without magnetic field. The number of machine unit (MU) for online adaptive plan was slightly higher than that of the reference plan, and the number of MU for the conventional accelerator standby treatment plan was significantly lower than that of the MR linac plan under the same target coverage. The follow-up results showed that there was no adverse reaction, and the short-term efficacy was partially relieved.Conclusions:In the case of considering the influence of magnetic field, the treatment plan meeting the clinical needs can be obtained. It is proven that SBRT radiotherapy for lung cancer guided by magnetic resonance accelerator is feasible, whereas the treatment time and process are complex.

Objective:To evaluate the carotid artery elasticity in severely abdominal obese children by RF-data based quantitative analysis on vessel stiffness (R-VQS), and explore the correlation between visceral fat distribution and carotid artery elasticity.Methods:Seventy severely abdominal obese children aged 7-14 years old and 55 healthy children with normal body mass index were selected as obese group and control group in Children′s Hospital Affiliated to Zhengzhou University from July 2018 to July 2019. Epicardial fat thickness (EFT), visceral fat thickness (VFT), subcutaneous fat thickness (SFT), maximum preperitoneal fat thickness (PFTmax), minimum subcutaneous fat thickness (SFTmin), perirenal fat thickness (PRFT) were measured by ultrasound. Real-time intima-media thickness (RIMT) and R-VQS were employed to evaluate common carotid intima-media thickness (IMT), systolic diameter (Diam), distance (Dist), pulse wave velocity (PWV) and hardness coefficient (HC). The correlation between fat thickness and carotid artery elasticity was analyzed.Results:There were statistically differences of common carotid IMT, elasticity parameters (IMT, Diam, Dist, PWV, HC) and fat thickness (EFT, VFT, SFT, PFTmax, SFTmin, PRFT) between two groups ( P<0.05). In obese children, PFTmax, VFT, EFT, PRFT were positively correlated with IMT, PWV, and HC (with IMT: r=0.334, 0.425, 0.415, 0.370, P<0.05; with PWV: r=0.853, 0.744, 0.590, 0.358, P<0.05; with HC: r=0.822, 0.691, 0.526, 0.320, P<0.05), and there was no correlation between SFT, SFTmin and IMT, PWV, HC( P>0.05). The degree of correlations between visceral fat thickness and carotid artery elasticity was PFTmax>VFT>EFT>PRFT, however, the correlations between EFT, PRFT and carotid elastic elasticity were weak ( r<0.7). Conclusions:R-VQS can sensitively reflect the carotid artery elasticity in severely abdominal obese children, and it can be used as an important reference indicator for early evaluation of atherosclerosis in obese children. Their visceral fat thickness (EFT, PRFT, VFT and PFTmax) have a good correlation with carotid artery elasticity, among which PFTmax has the best correlation and shows a certain clinical significance for the treatment and follow-up of obese children.

Objective:To assess the feasibility of delayed-enhancement MRI in contouring the lumpectomy cavity (LC) for patients with invisible seroma or a low cavity visualization score (CVS≤2) in the excision cavity after breast-conserving surgery (BCS).Methods:Twenty-six patients with stage T 1-2N 0M 0 who underwent prone radiotherapy after BCS were recruited. The LC delineated on CT simulation images was denoted as LC CT. The LCs delineated on T 2WI, as well as on different delayed phases (2-, 5-and 10-minute) of delayed-enhancement T 1WI were defined as LC T2, LC 2T1, LC 5T1 and LC 10T1, respectively. Subsequently, the volumes and locations of the LCs were compared between CT simulation images and different sequences of MR simulation images using deformable image registration. Results:The volumes of LC T2, LC 2T1, LC 5T1 and LC 10T1 were all larger than that of LC CT. A statistical significance was found between the volume of LC CT and those of LC 2T1 or LC 5T1, respectively (both P<0.05). The conformal index (CI), degree of inclusion (DI), dice similarity coefficient (DSC) and the distance between the center of mass of the targets (COM) of LC CT-LC 10T1 were better than those of LC CT-LC T2, LC CT-LC 2T1 and LC CT-LC 5T1, however, there was no statistical difference among them (all P>0.05). Conclusions:It is feasible to delineate the LC based on prone delayed-enhancement MR simulation images in patients with low CVS after BCS. Meanwhile, the LCs derived from prone delayed-enhancement T 1WI of 10-minute are the most similar with those derived from prone CT simulation scans using titanium clips, regardless of the volumes and locations of LCs.

Objective To investigate the value of ultrasonic two‐dimensional speckle tracking imaging ( 2D‐ST I) layer‐specific strain and transmural gradient in evaluating the changes of hypertensive patients′left ventricular three layers myocardial function . Methods Thirty‐five hypertensive patients without renal insufficiency were selected as group A ,and 25 hypertensive patients with renal insufficiency as group B .For comparison ,40 healthy volunteers were gathered as control group . T hen ,the systolic peak longitudinal strain of the left ventricle( LPS) ,endocardium( LPS Endo ) ,mid‐cardium ( LPSMid ) and epicardium ( LPSEpi ) were collected .After that ,features of transmural gradient ( ΔLS ) and its percentage ( ΔLS% ) were analyzed . Results For each group ,gradient features exist in each layer of left ventricular myocardium :LPS Endo ＞LPSMid＞LPSEpi . For each group ,the differences between LPSEndo and LPSMid ,and that between LPSEndo and LPSEpi were both statistically significant( P ＜0 .05) . When it came to the differences between LPS Mid and LPSEpi ,those of group A and control group were both statistically significant ( P ＜0 .05 ) . Compared with control group ,the LPSEndo of group A ,and LPSEndo ,LPSMid and LPSEpi of group B declined ,all the differences were statistically significant ( P ＜0 .05 ) . Compared with group A ,LPS Endo ,LPSMid and LPSEpi of group B declined ,the differences were statistically significant ( all P ＜0 .05) . For ΔLS′s differences among all three groups ,there was no statistical significance( P ＞0 .05) . Compared with control group ,the ΔLS% Endo‐Mid of group A rised , and the ΔLS% Endo‐Mid , ΔLS% Mid‐Epi of group B rised , the differences were statistically siginificant ( all P ＜ 0 .05 ) . Compared with group A ,the ΔLS% Endo‐Mid ,ΔLS% Mid‐Epi of group B rised ,the differences were statistically siginificant( all P ＜0 .05) . Conclusions T he layer‐specific strain technique can quantitatively evaluate the changes of systolic function of the left ventricular myocardium in hypertensive patients . ΔLS% may have better sensitivity than ΔLS in dection of systolic function damage of the left ventricular myocardium and can provide more reference for the evaluation of left ventricular systolic function .

Objective To quantitatively evaluate left ventricular ( LV ) systolic function in bicuspid aortic valve (BAV) using layer-specific strain ( LSS) . Methods Thirty BAV patients were divided into normal function (NF) group (10 cases) and non-normal function (N-NF) group (20 cases) based on aortic valvular lesion types ,and 20 healthy volunteers were taken as control group . Longitudinal strain( LS) and circumferential strain (CS) of three-layer myocardium and full thickness myocardium were assessed using layer-specific speckletracking imaging ,available by GE Vivid E9 and EchoPac workstation . Results There was no significant difference in left ventricular ejection fraction( LVEF) among the N-NF group ,NF group and control group ( P > 0 .05) ,all of them within the normal range[(63 .3 ± 7 .1)％ ,(64 .6 ± 6 .2)％ , ( 65 .3 ± 3 .9)％ ] . It showed a gradient decrease from the endocardium to the epicardium in both control and BAV group . LS of endocardium ( LSendo) and LS of epicardium ( LSepi) in N-NF group and NF group were significantly reduced compared with those in control group ( P <0 .05) [ LSendo :( -21 .19 ± 3 .12)％vs ( -23 .06 ± 2 .07 )％ vs ( -25 .53 ± 2 .51 )％ ;LSepi:( -16 .08 ± 2 .68 )％ vs ( -18 .85 ± 2 .12 )％ vs ( -20 .72 ± 2 .28)％ ] . Compared with control group ,there was no significant difference in NF group in CS of the three-layer myocardial and full-thickness myocardium as well as the LS of the whole medial myocardial layers and full-thickness ( P > 0 .05 ) . Compared with NF group [ CS :( -19 .57 ± 2 .9 )％ vs ( -13 .43 ± 2 .19)％ vs ( -20 .03 ± 3 .04)％ ;LS :( -21 .38 ± 2 .05)％ vs ( -18 .85 ± 2 .12)％ vs ( -21 .09 ± 2 .03)％ ] and control group[CS :( -21 .63 ± 3 .01)％ vs ( -14 .34 ± 2 .55)％ vs ( -21 .48 ± 2 .16)％ ;LS :( -22 .18 ± 2 .30 )％ vs ( -20 .72 ± 2 .28 )％ vs ( -22 .89 ± 2 .30 )％ ] , CS [ ( -16 .78 ± 3 .65 )％ vs ( -11 .40 ± 3 .78 )％ vs ( -15 .83 ± 2 .61 )％ ] and LS [ ( -18 .34 ± 2 .85 )％ vs ( -16 .08 ± 2 .68 )％ vs ( -18 .51 ± 2 .86)％ ] of middle myocardium ,epicardial myocardium and full-thickness myocardium in N-NF group were decreased significantly ( P < 0 .05) . Conclusions It is essential to maintain normal valvular function to prevent the progress of myocardial deterioration . LSendo and LSepi can be used to sensitively identify early left ventricular systolic dysfunction in BAV patients with normal LVEF .

Objective To investigate the difference of target volumes and dosimetric parameters between supine and prone positions for external-beam partial breast irradiation (EB-PBI) after breastconserving surgery (BCS).Methods Thirty breast cancer patients with T1N0M0 stage who underwent three-dimensional conformal radiation therapy (3D-CRT) EB-PBI after BCS were enrolled from July 2016 to April 2017.Supine and prone scan sets were acquired during free breathing for all patients.Target volumes and organs at risk (OARs) including heart,ipsilateral lung and bilateral breast were contoured by the same radiation oncologist.The tumor bed (TB) was determined based on surgical clips.The clinical target volume (CTV) consisted of the TB plus 1.0 cm margin and the planning target volume (PTV) was CTV plus 0.5 cm.Dosimetric parameters for target volumes and OARs were compared between supine and prone positions.Results The median volumes of the TB,the CTV and the PTV in supine were 14.40 cm3,57.35 cm3,108.85 cm3 and 14.10 cm3,62.60 cm3,113.70 cm3 for prone positions,respectively.The CTV and PTV in prone position were significantly greater than those in supine position,respectively (Z=-3.01,-2.87,P ＜0.05),but the TBs were not statistically different (P ＞0.05).The median homogeneity indexs (HI) in supine position was less than those in prone position (Z =-3.137,P ＜0.05),while the mean conformal indexs (CI) was increased with prone positioning (t =9.034,P ＜ 0.05).The mean dose (D) to the heart in the supine position was significantly lower than that in prone (0.34 and 1.19 Gy,Z =-4.12,P ＜0.05).The D to the ipsilateral lung in the prone position was significantly lower than that in supine (1.59 and 1.72 Gy,Z =-2.18,P ＜ 0.05).There was not significantly statistical difference for the D to the ipsilateral breast between two positionings (10.01 and 10.40 Gy,P ＞0.05).Conclusions It was feasible to carry out 3D-CRT EB-PBI in prone position in free breathing for Chinese breast cancer patient,with primary advantages of better CI and the significantly lower radiation dose to the ipsilateral lung.