Objective:To conduct enrichment and biological behavior studies on CD44 + CD24 - triple-negative breast cancer (TNBC) stem-like cells, and to construct 68Ga-labeled CD44 peptide ( 68Ga-1, 4, 7-triazacyclononane-1, 4, 7-triacetic acid (NOTA)-CD44p) and evaluate its targeting ability towards the surface marker CD44 of TNBC stem-like cells. Methods:Suspension sphere culture method was utilized to enrich and cultivate CD44 + CD24 - cell subpopulations from TNBC cell line MDA-MB-231 and non-TNBC cell line MCF-7. Flow cytometry was used to detect the expression of stem cell markers of different groups, cell scratch assay was performed to assess the migration ability of CD44 + CD24 - cell subpopulations, and Transwell invasion assay was performed to evaluate the invasion ability of CD44 + CD24 - cell subpopulations. 68Ga-NOTA-CD44p was prepared, followed by purification and identification with high-performance liquid chromatography (HPLC). The targeting ability of 68Ga-NOTA-CD44p towards CD44 + TNBC cells was evaluated through cellular uptake and blocking experiments. Data were analyzed by independent-sample t test, one-way analysis of variance and the least significant difference t test. Results:Suspension sphere culture successfully enriched CD44 + CD24 - TNBC stem-like cell spheres. Compared to the non-TNBC cell line MCF-7, TNBC cell line MDA-MB-231 exhibited better sphere-forming ability (18.50±3.73 vs 31.83±4.92; t=5.29, P<0.001) and a higher proportion of CD44 + CD24 - cell subset ((24.97±8.12)% vs (90.93±4.46)%; F=170.10, t=14.93, both P<0.001). The wound healing rate ((71.00±11.00)% vs (28.33±4.16)%; F=42.91, t=8.02, both P<0.001) and invasion rate ((60.60±16.87)% vs (24.16±8.15)%; F=11.83, t=4.40, both P<0.01) of CD44 + CD24 - MDA-MB-231 group cells were significantly increased compared to the CD44 + CD24 - MCF-7 group. MDA-MB-231 cells showed strong uptake ability of 68Ga-NOTA-CD44p, which decreased after CD44p blocking. Conclusions:Compared to CD44 + CD24 - MCF-7 cells, CD44 + CD24 - MDA-MB-231 cells exhibit higher malignant biological behavior. 68Ga-NOTA-CD44p targets the surface marker CD44 of TNBC stem-like cells, laying the research foundation for targeted therapy against TNBC with tumor stem cells as targets.

Objectives:To investigate the enhancement of tumor penetration and photodynamic therapy (PDT) efficacy in triple-negative breast cancer by hyaluronidase (HAase) using a novel pH-responsive IR780-loaded photosensitive micelle.Methods:The pH-responsive IR780-loaded photosensitive micelles were prepared using the nanoprecipitation method, and their morphology, size, and encapsulation efficiency were characterized. The in vitro stability and pH-responsive drug release of the micelles were also evaluated. The cytotoxicity of the micelles on triple-negative breast cancer cells (MDA-MB-231) was assessed using a cell counting kit. A nude mouse breast cancer model was established, and HAase was injected intratumorally 24 hours before intravenous injection of the photosensitive micelles. The effect of HAase on the biodistribution and tumor uptake of the micelles was detected using small animal in vivo imaging. CD31 and HIF-1α immunofluorescence staining were performed to investigate the mechanism of HAase-enhanced tumor penetration. The body weight and tumor volume of the mice were measured, and necrosis and apoptosis of tumor tissues were assessed using HE staining and TUNEL staining, respectively. Results:Transmission electron microscopy showed that the micelles had a uniform particle size of approximately 60-70 nm, with a hydrated particle size of (98.03±0.22) nm. The IR780 encapsulation efficiency was 74.15%, with a drug loading content of 2.07%. After 7 days at 4 ℃, there was no significant change in hydrated particle size ( P=0.062). The 24-hour release rates of the micelles in PBS at pH 7.4 and 6.5 were (2.41±0.21)% and (43.69±2.09)%, respectively, showing a significant difference ( P＜0.000 1). The cytotoxicity assay revealed that the cell viability in the micelles group without light exposure was significantly higer than that in the micelles group under light exposure [(97.00±5.38)% vs. (53.27±9.00)%, P=0.000 2]. The micelles were able to target and accumulate in the tumor tissue, and this accumulation increased significantly with HAase treatment. CD31 and HIF-1α immunofluorescence staining indicated that the CD31 signal was enhanced [(0.27±0.05)% vs. (4.57±0.27)%, P＜0.000 1] and the HIF-1α signal was reduced [(5.14±0.38)% vs. (0.08±0.04)%, P＜0.000 1] in the HAase-treated group compared to that in the micelle-only group. After 11 days of treatment with HAase combined with photosensitive micelles, there was no statistically significant difference in mouse body weight ( P＞0.05). However, the tumor volume inhibition rate in the HAase-micelle-mediated PDT group was significantly higher than that in the micelle-mediated PDT group [(87.66±6.37)% vs. (25.34±12.63)%, P=0.002]. Histological staining showed a significant increase in tumor cell necrosis and apoptosis in the HAase-micelle-mediated PDT group. Conclusion:HAase enhances the deep tumor penetration and targeted accumulation of pH-responsive IR780-loaded photosensitive micelles, significantly improves the efficacy of photodynamic therapy in triple-negative breast cancer.

Objectives:To investigate the enhancement of tumor penetration and photodynamic therapy (PDT) efficacy in triple-negative breast cancer by hyaluronidase (HAase) using a novel pH-responsive IR780-loaded photosensitive micelle.Methods:The pH-responsive IR780-loaded photosensitive micelles were prepared using the nanoprecipitation method, and their morphology, size, and encapsulation efficiency were characterized. The in vitro stability and pH-responsive drug release of the micelles were also evaluated. The cytotoxicity of the micelles on triple-negative breast cancer cells (MDA-MB-231) was assessed using a cell counting kit. A nude mouse breast cancer model was established, and HAase was injected intratumorally 24 hours before intravenous injection of the photosensitive micelles. The effect of HAase on the biodistribution and tumor uptake of the micelles was detected using small animal in vivo imaging. CD31 and HIF-1α immunofluorescence staining were performed to investigate the mechanism of HAase-enhanced tumor penetration. The body weight and tumor volume of the mice were measured, and necrosis and apoptosis of tumor tissues were assessed using HE staining and TUNEL staining, respectively. Results:Transmission electron microscopy showed that the micelles had a uniform particle size of approximately 60-70 nm, with a hydrated particle size of (98.03±0.22) nm. The IR780 encapsulation efficiency was 74.15%, with a drug loading content of 2.07%. After 7 days at 4 ℃, there was no significant change in hydrated particle size ( P=0.062). The 24-hour release rates of the micelles in PBS at pH 7.4 and 6.5 were (2.41±0.21)% and (43.69±2.09)%, respectively, showing a significant difference ( P＜0.000 1). The cytotoxicity assay revealed that the cell viability in the micelles group without light exposure was significantly higer than that in the micelles group under light exposure [(97.00±5.38)% vs. (53.27±9.00)%, P=0.000 2]. The micelles were able to target and accumulate in the tumor tissue, and this accumulation increased significantly with HAase treatment. CD31 and HIF-1α immunofluorescence staining indicated that the CD31 signal was enhanced [(0.27±0.05)% vs. (4.57±0.27)%, P＜0.000 1] and the HIF-1α signal was reduced [(5.14±0.38)% vs. (0.08±0.04)%, P＜0.000 1] in the HAase-treated group compared to that in the micelle-only group. After 11 days of treatment with HAase combined with photosensitive micelles, there was no statistically significant difference in mouse body weight ( P＞0.05). However, the tumor volume inhibition rate in the HAase-micelle-mediated PDT group was significantly higher than that in the micelle-mediated PDT group [(87.66±6.37)% vs. (25.34±12.63)%, P=0.002]. Histological staining showed a significant increase in tumor cell necrosis and apoptosis in the HAase-micelle-mediated PDT group. Conclusion:HAase enhances the deep tumor penetration and targeted accumulation of pH-responsive IR780-loaded photosensitive micelles, significantly improves the efficacy of photodynamic therapy in triple-negative breast cancer.

Objective:To conduct enrichment and biological behavior studies on CD44 + CD24 - triple-negative breast cancer (TNBC) stem-like cells, and to construct 68Ga-labeled CD44 peptide ( 68Ga-1, 4, 7-triazacyclononane-1, 4, 7-triacetic acid (NOTA)-CD44p) and evaluate its targeting ability towards the surface marker CD44 of TNBC stem-like cells. Methods:Suspension sphere culture method was utilized to enrich and cultivate CD44 + CD24 - cell subpopulations from TNBC cell line MDA-MB-231 and non-TNBC cell line MCF-7. Flow cytometry was used to detect the expression of stem cell markers of different groups, cell scratch assay was performed to assess the migration ability of CD44 + CD24 - cell subpopulations, and Transwell invasion assay was performed to evaluate the invasion ability of CD44 + CD24 - cell subpopulations. 68Ga-NOTA-CD44p was prepared, followed by purification and identification with high-performance liquid chromatography (HPLC). The targeting ability of 68Ga-NOTA-CD44p towards CD44 + TNBC cells was evaluated through cellular uptake and blocking experiments. Data were analyzed by independent-sample t test, one-way analysis of variance and the least significant difference t test. Results:Suspension sphere culture successfully enriched CD44 + CD24 - TNBC stem-like cell spheres. Compared to the non-TNBC cell line MCF-7, TNBC cell line MDA-MB-231 exhibited better sphere-forming ability (18.50±3.73 vs 31.83±4.92; t=5.29, P<0.001) and a higher proportion of CD44 + CD24 - cell subset ((24.97±8.12)% vs (90.93±4.46)%; F=170.10, t=14.93, both P<0.001). The wound healing rate ((71.00±11.00)% vs (28.33±4.16)%; F=42.91, t=8.02, both P<0.001) and invasion rate ((60.60±16.87)% vs (24.16±8.15)%; F=11.83, t=4.40, both P<0.01) of CD44 + CD24 - MDA-MB-231 group cells were significantly increased compared to the CD44 + CD24 - MCF-7 group. MDA-MB-231 cells showed strong uptake ability of 68Ga-NOTA-CD44p, which decreased after CD44p blocking. Conclusions:Compared to CD44 + CD24 - MCF-7 cells, CD44 + CD24 - MDA-MB-231 cells exhibit higher malignant biological behavior. 68Ga-NOTA-CD44p targets the surface marker CD44 of TNBC stem-like cells, laying the research foundation for targeted therapy against TNBC with tumor stem cells as targets.

Objective:Aromatase inhibitor-induced arthralgia(AIA)is an adverse effect observed in patients treated with aromatase inhibit-ors.This study aimed to establish a predictive model for AIA in patients with breast cancer living in high-altitude regions.Methods:A retro-spective analysis was conducted on 315 patients with breast cancer who received aromatase inhibitor treatment at the Affiliated Hospital of Qinghai University between June 2021 and October 2023.Patients were randomly allocated to the training set(n=220)or validation set(n=95)in a 7:3 ratio.Variable selection was performed using the least absolute shrinkage and selection operator(LASSO)regression fol-lowed by 7-fold cross-validation.Multivariate Logistic regression analysis was conducted on the training set to identify independent risk factors for AIA,leading to the establishment of a nomogram.The performance of the model was assessed using calibration plots,receiver operating characteristic(ROC)curves,and decision curve analysis(DCA).Results:Multivariate Logistic regression analysis identified several significant independent predictors for AIA in patients with breast cancer from high-altitude regions,including prior taxane chemotherapy(odds ratio(OR)=10.174,95%confidence interval(CI):2.008-62.69,P=0.008),years since last menstrual period(LMP)(OR=0.175,95%CI:0.052-0.494,P=0.002),drug-induced menopause(OR=3.834,95%CI:1.109-14.13,P=0.036),cancer stage(OR=10.423,95%CI:4.114-32.15,P<0.001),and psychological factors(OR=25.108,95%CI:8.430-87.95,P<0.001).The AIA incidence rate in this cohort was 58.41%,while the area under the ROC curve was 0.971.

Objective:To explore the application and nursing of chest radiograph combined with body surface measurement in measuring the length of PICC intubation in tumor patients.Methods:Totally 60 cases of malignant tumor patients in our hospital from March 2019 to January 2020 were selected and randomly divided into two groups by the method of random number table. 30 cases in the control group were given PICC catheterization by conventional body surface measurement; 30 cases in the observation group were given PICC catheterization combined with chest imaging data. After the intervention, the precise position of PICC catheter, indwelling time, complications, nursing satisfaction rate and quality of life were compared between the two groups.Results:After the intervention, the accurate placement rate, adjustment ratio and indwelling time of the observation group were 100.00% (30/30), 0, (146.35±21.74) d, which were significantly better than 83.33% (25/30), 16.67% (5/30) and (118.44±17.36) d of the control group, the difference was statistically significant ( tvalue was 5.495, χ 2values were 4.286, 5.455, all P<0.05); after intervention the complication rate, nursing satisfaction rate, and quality of life score in the observation group were 3.33% (1/30), 99.67% (29/30), (91.35±8.58) points, which were significantly better than the control group's 26.67% (8/30), 80.00% (24/30), (83.57±7.36) points, the difference was statistically significant ( χ 2values were 6.405, 4.043, tvalue was 3.775, P<0.05 or 0.01). Conclusion:Chest imaging data combined with body surface measurement methods combined with comprehensive care can significantly improve the accuracy of PICC catheter placement in cancer patients, reduce catheter adjustment and the deviation of actual length from the ideal length, extend the indwelling time, reduce complications, and improve patients Care satisfaction rate and quality of life.

Objective To explore the relationship between the fibroblast growth factor 2 (FGFR2) gene polymorphism (rs 2981582 ,rs 1219648 ,rs 2420946) and the breast cancer risk in Tibetan population ,Qinghai province .Methods This is a case con‐trol study .Peripheral blood samples from 210 breast cancer patients and 230 healthy women in Qinghai area were collected .DNA samples were extracted from peripheral blood cells .FGFR2 gene polymorphism (rs 2981582 ,rs 1219648 ,rs 2420946) were typed by Taqman‐MGB probe based on PCR and DNA sequencing ,then analyzed its correlation with breast cancer in Tibetan population , Qinghai province .Results The genotype frequencies of rs 2981582 CC ,CT and TT were 40 .48% ,39 .05% and 20 .47% among the breast cancer patients while 36 .09% ,48 .69% and 15 .22% among the controls .The genotype frequencies of rs 1219648 GG ,AG and AA were 24 .76% ,26 .19 % and 49 .05% among the patients while 23 .91% ,47 .39% and 28 .70% among the controls .The genotype frequencies of rs 2420946 CC ,CT and TT were 29 .05% ,45 .24% and 25 .71% among the patients while 30 .87% , 51 .74% and 17 .39% among the controls .The genotype frequencies of all genetic loci had no significant difference between rs 2981582 and rs 2420946 (P>0 .05) .But the genotype frequencies of rs 1219648 AA have statistical sense (P< 0 .05) ,compared with GG ,the incidence of breast cancer was remarkably increased with AA [OR=1 .65 ,95% CI= (1 .01 ,2 .69)] .Conclusion This study shows that FGFR2 rs1219648 AA is related to breast cancer risk among Tibetan population .

Purpose To detect the expression of Snai2 mRNA in gastric carcinoma and normal gastric mucosa and analyze its significance.Methods Total RNA was extracted with TRIzol from 30 cases of gastric carcinoma and mRNA was transcribed reversely into cDNA.The expression of Snai2 mRNA was examined by real-time PCR; then mRNA probes were prepared, the expression of Snai2 mRNA was detected by in situ hybridization on a tissue array,including normal gastric mucosa (20 cases) and gastric carcinoma (100 cases).Results Real-time PCR data showed they had different expression in different degrees of differentiation of the cancer: the poorer differentiation, the more expression (P<0.05). In situ hybridization results showed the positive rate in the carcinoma (54.2%) was higher than normal tissue (27.8%), with statistically significant difference (P<0.05).There were different positive rate in different degrees of differentiation: the poorer differentiation,the higher positive rate, but it had no statistical significance (P>0.05).Conclusions Snai2 could be a biomarker of malignant degree and disease progression,and used as a useful tool for evaluation of prognosis.