[Antitumor effects of redox-responsive nanoparticles containing platinum（⠣）in ovarian cancer].

Objectives: To explore the antitumor effects of redox-responsive nanoparticles containing platinum(Ⅳ)-NP@Pt(Ⅳ) in ovarian cancer. Methods: Redox-responsive polymer carriers were synthesized. Polymer carriers and platinum(Ⅳ)-Pt(Ⅳ) can self-assemble into NP@Pt(Ⅳ). Inductively coupled plasma mass spectrometry was performed to detect the platinum release from NP@Pt(Ⅳ) in reducing environment and the platinum content in ovarian cancer cells ES2 treated with cisplatin, Pt(Ⅳ) and NP@Pt(Ⅳ). The proliferation ability of the ovarian cancer cells were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cellular apoptosis was assessed by flow cytometry. Collection of primary ovarian cancer tissues from patients with primary high-grade serous ovarian cancer who were surgically treated at the Cancer Hospital of the Chinese Academy of Medical Sciences from October to December 2022. The high-grade serous ovarian cancer patient-derived xenograft (PDX) mice were intravenously injected with Cy7.5 labeled NP@Pt(Ⅳ) followed by in vivo imaging system. Mice were treated with PBS, cisplatin and NP@Pt(Ⅳ). Tumor volume and weight were measured in each group. Necrosis, apoptosis and cell proliferation of tumor tissues were detected by hematoxylin-eosin (HE) staining, TUNEL fluorescence staining and Ki-67 immunohistochemistry staining. Body weight and HE staining of heart, liver, spleen, lung and kidney of mice in each group were measured. Results: The platinum release of NP@Pt(Ⅳ) after 48 hours in reducing environment was 76.29%, which was significantly higher than that of 26.82% in non-reducing environment (P<0.001). The platinum content in ES2 cells after 4 hours and 7 hours of treatment with NP@Pt(Ⅳ) (308.59, 553.15 ng/million cells) were significantly higher than those of Pt(Ⅳ) (100.21, 180.31 ng/million cells) and cisplatin (43.36, 50.36 ng/million cells, P＜0.05). The half inhibitory concentrations of NP@Pt(Ⅳ) in ovarian cancer cells ES2, A2780, A2780DDP were 1.39, 1.42 and 4.62 µmol/L, respectively, which were lower than those of Pt(IV) (2.89, 7.27, and 16.74 µmol/L) and cisplatin (5.21, 11.85, and 71.98 µmol/L). The apoptosis rate of ES2 cells treated with NP@Pt(Ⅳ) was (33.91±3.80)%, which was significantly higher than that of Pt(Ⅳ) [(16.28±2.41)%] and cisplatin [(15.01±1.17)%, P＜0.05]. In high-grade serous ovarian cancer PDX model, targeted accumulation of Cy7.5 labeled NP@Pt(Ⅳ) at tumor tissue could be observed. After the treatment, the tumor volume of mice in NP@Pt(IV) group was (130±98) mm3, which was significantly lower than those in control group [(1 349±161) mm3, P<0.001] and cisplatin group [(715±293) mm3, P=0.026]. The tumor weight of mice in NP@Pt(IV) group was (0.17±0.09)g, which was significantly lower than those in control group [(1.55±0.11)g, P<0.001] and cisplatin group [(0.82±0.38)g, P=0.029]. The areas of tumor necrosis and apoptosis in mice treated with NP@Pt(Ⅳ) were higher than those in mice treated with cisplatin. Immunohistochemical staining revealed that there were low expressions of Ki-67 at tumor tissues of mice treated with NP@Pt(Ⅳ) compared with cisplatin. The change in body weight of mice in NP@Pt(Ⅳ) group was not significantly different from that of the control group [(18.56±2.04)g vs.(20.87±0.79)g, P=0.063]. Moreover, the major organs of the heart, liver, spleen, lung, and kidney were also normal by HE staining. Conclusion: Redox-responsive NP@Pt(Ⅳ), produced in this study can enhance the accumulation of cisplatin in ovarian cancer cells and improve the efficacy of ovarian cancer chemotherapy.

[Signal transducer and activator of transcription 3 and cancer associated fibroblasts jointly generate chemo-resistance and affect prognosis in epithelial ovarian cancer].

Objective: To investigate the mechanism of signal transducer and activator of transcription 3 (STAT3) and cancer associated fibroblasts (CAF) jointly generate chemo-resistance in epithelial-ovarian cancer and their effect on prognosis. Methods: A total of 119 patients with high-grade ovarian serous cancer who received surgery in Cancer Hospital of Chinese Academy of Medical Sciences from September 2009 to October 2017 were collected. The clinico-pathological data and follow-up data were complete. Multivariate Cox regression model was used to analyze the prognostic factors. Ovarian cancer tissue chips of patients in our hospital were prepared. EnVision two-step method immunohistochemistry was used to detect the protein expression levels of STAT3, the specific markers of CAF activation, fibroblast activating protein (FAP), and type Ⅰ collagen (COL1A1) secreted by CAF. The relationship between the expression of STAT3, FAP, COL1A1 protein and drug resistance and prognosis of ovarian cancer patients was analyzed, and the correlation between the expression of three proteins was analyzed. These results were verified through the gene expression and prognostic information of human ovarian cancer tissues collected in the GSE26712 dataset of gene expression omnibus (GEO) database. Results: (1) Multivariate Cox regression model analysis showed that chemotherapy resistance was an independent risk factor for overall survival (OS) of ovarian cancer (P<0.001). (2) The expression levels of STAT3, FAP, and COL1A1 proteins in chemotherapy resistant patients were significantly higher than those in chemotherapy sensitive patients (all P<0.05). Patients with high expression of STAT3, FAP, and COL1A1 had significantly shorter OS than those with low expression (all P<0.05). According to the human ovarian cancer GSE26712 dataset of GEO database, patients with high expression of STAT3, FAP, and COL1A1 also showed shorter OS than patients with low expression (all P<0.05), the verification results were consistent with the detection results of ovarian cancer patients in our hospital. (3) Correlation analysis showed that the protein level of STAT3 was positively correlated with FAP and COL1A1 in our hospital's ovarian cancer tissue chips (r=0.47, P<0.001; r=0.30, P=0.006), the analysis of GEO database GSE26712 dataset showed that the expression of STAT3 gene and FAP, COL1A1 gene were also significantly positively correlated (r=0.31, P<0.001; r=0.52, P<0.001). Conclusion: STAT3 and CAF could promote chemotherapy resistance of ovarian cancer and lead to poor prognosis.

p75NTR ectodomain is a physiological neuroprotective molecule against amyloid-beta toxicity in the brain of Alzheimer's disease.

In Alzheimer's disease (AD), neurodegenerative signals such as amyloid-beta (Aß) and the precursors of neurotrophins, outbalance neurotrophic signals, causing synaptic dysfunction and neurodegeneration. The neurotrophin receptor p75 (p75NTR) is a receptor of Aß and mediates Aß-induced neurodegenerative signals. The shedding of its ectodomain from the cell surface is physiologically regulated; however, the function of the diffusible p75NTR ectodomain (p75ECD) after shedding remains largely not known. Here, we show that p75ECD levels in cerebrospinal fluid and in the brains of Alzheimer's patients and amyloid-beta precursor protein (APP)/PS1 transgenic mice were significantly reduced, due to inhibition of the sheddase-tumor necrosis factor-alpha-converting enzyme by Aß. Restoration of p75ECD to the normal level by brain delivery of the gene encoding human p75ECD before or after Aß deposition in the brain of APP/PS1 mice reversed the behavioral deficits and AD-type pathologies, such as Aß deposit, apoptotic events, neuroinflammation, Tau phosphorylation and loss of dendritic spine, neuronal structures and synaptic proteins. Furthermore, p75ECD can also reduce amyloidogenesis by suppressing ß-secretase expression and activities. Our data demonstrate that p75ECD is a physiologically neuroprotective molecule against Aß toxicity and would be a novel therapeutic target and biomarker for AD.

Inhibitory efficacy of hypoxia-inducible factor 1alpha short hairpin RNA plasmid DNA-loaded poly (D, L-lactide-co-glycolide) nanoparticles on choroidal neovascularization in a laser-induced rat model.

The aim of this study was to evaluate the possibility of poly (D, L-lactide-co-glycolide) nanoparticle (NPs) as a gene vector for functional plasmid DNA (pDNA) and to investigate its inhibitory efficacy on experimental choroidal neovascularization (CNV). We developed intravitreal administered, hypoxia-inducible factor 1alpha (HIF-1alpha) short hairpin RNA and green fluorescent protein (GFP) co-expressed pDNA-loaded NPs (pshHIF-1alpha NPs). CNV was induced by laser photocoagulation in 112 rats. The rats were then randomly assigned to be injected intravitreally with phosphate-buffered saline (PBS), blank NPs, naked pDNA, control pDNA NPs and pshHIF-1alpha NPs, respectively, and non-injection group was set as the control. Immunofluorescence staining, fluorescein fundus angiography and histologic analysis were performed to evaluate the inhibitory efficacy on CNV. The results showed that the expression of GFP preferentially localized in the retinal pigment epithelium cell layer and lasted for 4 weeks. The fluorescein leakage areas of CNV were significantly larger in the PBS, blank NPs, control pDNA NPs, non-injection group and naked pDNA group than in pshHIF-1alpha NPs group (P<0.01). The mean thickness of the CNV lesions in the intravitreally pshHIF-1alpha NPs-treated group was significantly smaller than other groups (P<0.01). No signs of functional or ultrastructural destruction in retina were detected. Therefore, pshHIF-1alpha NPs may act as a novel therapeutic option to transfer specific pDNA and inhibit the formation of experimental CNV.

The role of bowel surgery with cytoreduction for epithelial ovarian cancer.

AIMS: To assess the efficiency and morbidity associated with bowel resection with the initial cytoreduction procedure for advanced ovarian cancer. MATERIALS AND METHODS: A review was carried of 95 patients with ovarian cancer who underwent cytoreductive surgery between 2000 and 2003. The relationship between dichotomised preoperative, intra-operative and postoperative outcome variables were tested using SPSS software. Kaplan-Meier curves were generated to compare survival. Cox proportional hazards regression was used to determine the independent significance of factors after cytoreductive surgery. RESULTS: In patients in whom bowel resection was carried out, the largest residual tumour mass was <1cm in 66.67% of patients, compared with 45.28% of patients undergoing surgery without bowel resection (P=0.038). The median survival in the optimally debulked patients was 50.38 months compared with 37.15 months in the patients who had suboptimal cytoreduction (P=0.0021). The median survival in patients undergoing bowel resection was 50.70 months compared with 44.62 months in the patients who had cytoreduction without bowel resection (P=0.2176). Multivariate analysis showed that optimal cytoreduction (P=0.005) was found to be independently prognostic for overall survival. Major adverse events, such as ileus, intestinal fistulae, urinary tract fistulae, were not significantly different between groups. CONCLUSION: Bowel resection is a worthwhile endeavour in selected patients with advanced ovarian cancer to increase therapeutic efficiency. The surgical morbidity rate from these procedures is not serious and seems acceptable.

Using the TBAg/PHA ratio in the T-SPOT(®).TB assay to distinguish TB disease from LTBI in an endemic area.

SETTING: An important limitation of the T-SPOT(®).TB assay is its inability to distinguish active tuberculosis (TB) from latent tuberculous infection (LTBI). OBJECTIVE: We proposed a new calculation method for the T-SPOT assay and assessed its effect on distinguishing active TB from LTBI. DESIGN: A total of 162 active TB patients and 97 LTBI individuals were diagnosed according to conventional tests and the T-SPOT assay. RESULTS: The results of early secreted antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) in T-SPOT cannot be recommended for distinguishing TB from LTBI. The number of phytohaemagglutinin (PHA) spot-forming cells (sfc) in the T-SPOT assay was reduced in active TB patients. The ESAT-6/PHA or CFP-10/PHA ratios in active TB patients were significantly higher than in individuals with LTBI. Using 0.295 as the threshold ratio of Mycobacterium tuberculosis-specific antigen (TBAg) sfc to PHA sfc (TBAg/PHA ratio, the larger of ESAT-6/PHA and CFP-10/PHA), the sensitivity and specificity were 82.1% and 90.7% in distinguishing active TB from LTBI. The TBAg/PHA ratio might also be used to monitor the effect of anti-tuberculosis treatment. CONCLUSIONS: Calculating the TBAg/PHA ratio might have the potential to diagnose active TB and distinguish TB disease from LTBI.

[The sub-cellular distribution of beta-catenin in the neural differentiation of RA induced P19 EC cells].

Wnt signals have been shown to play an important role in the development of the central nervous system (CNS) of mouse. In our previous work, it was demonstrated that Wnt signal could initiate differentiation of P19 EC cells. In the present investigation, it was examined with RT-PCR whether expression of beta-catenin, a downstream gene of Wnt in its signal transduction pathway, is regulated. It was found that the level of protein or transcript beta-catenin during P19 neuronal differentiation was not changed. However, immunostaining data showed that beta-catenin was translocalized into nuclei after retinoic acid induced P19 cell aggregates were trypsinized and cultured in serum free N2 medium for 2 and 4 d. In this period, transcription of En-2, a downstream target gene of Wnt signal, increased evidently. The above data suggest that Wnt signals are involved in the early stage of neuronal differentiation process of P19 cell. Meanwhile, the distribution of beta-catenin on the neurites indicates that this protein may also be involved in neuritis outgrowth process.