Investigator
Chinese Academy Of Medical Sciences Peking Union Medical College
Tumor‐Derived Exosomes Promote Tumor Growth Through Modulating Microvascular Hemodynamics in a Human Ovarian Cancer Xenograft Model
ABSTRACTObjectiveAbnormal tumor vascular network contributes to aberrant blood perfusion and reduced oxygenation in tumors, which lead to poor efficacy of chemotherapy and radiotherapy. We aimed to explore the effects of the tumor‐derived exosomes (TDEs) and C188‐9 (a small molecule inhibitor of signal transducer and activator of transcription 3, STAT3) on tumor microvascular hemodynamics and determine which blood flow oscillations for various frequency intervals are responsible for these changes.MethodsMicrovascular hemodynamics parameters were recorded using a PeriFlux 6000 EPOS system in tumor surface in a nude mouse subcutaneous xenograft model. Oscillations of laser Doppler flowmetry (LDF) signal were investigated by wavelet transform analysis.ResultsTDEs facilitated tumor growth at least partially was associated with increasing blood flow in smaller vessels with lower speed and decreasing the blood flow at larger vessels with higher speed. Lower oxyhemoglobin saturation (SO2) on tumor surface was aggravated by TDEs, and C188‐9 treatment significantly alleviated this decrease. Wavelet transform spectral analysis revealed that TDEs increased the amplitude of oscillations in four frequency intervals related to endothelial (NO‐dependent and ‐independent), myogenic and neurogenic activities, and C188‐9 had no effect on this increase.ConclusionsTDEs facilitated tumor growth partially was associated with increasing blood flow in distributing vessels, reducing blood perfusion in larger vessels, and lowering SO2 on tumor surface. Enhanced vascular smooth muscle, endothelial and neurogenic activities occurred in tumor superficial zone.
TAZ Regulates the Cisplatin Resistance of Epithelial Ovarian Cancer Cells via the ANGPTL4/SOX2 Axis
Objective. Epithelial ovarian cancer (EOC) is a fatal gynecological malignancy. This study explored the mechanism of TAZ in regulating drug sensitivity of cisplatin (DDP-)-resistant EOC cells through the ANGPTL4/SOX2 axis. Methods. The A2780/DDP cells were prepared by stepwise progressive concentration method. The drug resistance and TAZ expression in EOC cells were determined. Drug sensitivity was measured after TAZ overexpression in A2780 cells and TAZ downregulation in A2780/DDP cells, respectively. The effects of TAZ knockdown on apoptosis rate, stemness, and cancer stem cell (CSC) marker (CD44, OCT4, and ALDH1A) levels in A2780/DDP and DDP-treated A2780/DDP cells were assessed. The binding of TAZ and ANGPTL4 was verified using ChIP-qPCR, and ANGPTL4 and SOX2 levels were determined. The effects of different combined treatments of TAZ, ANGPTL4, and SOX2 on drug sensitivity of A2780/DDP cells and DDP-treated A2780/DDP cells were evaluated. Results. TAZ was upregulated in drug-resistant EOC cells. TAZ knockdown significantly increased the drug sensitivity of A2780/DDP cells, while TAZ overexpression markedly decreased the drug sensitivity of A2780 cells. TAZ silencing promoted apoptosis of drug-resistant EOC cells and inhibited cell stemness. TAZ targeted ANGPTL4 and TAZ silencing enhanced drug sensitivity of A2780/DDP cells by inhibiting ANGPTL4. ANGPTL4 overexpression elevated SOX2 expression, and SOX2 downregulation reduced the drug resistance and promoted the apoptosis of A2780/DDP cells. Conclusion. TAZ regulates DDP sensitivity of drug-resistant EOC cells via the ANGPTL4/SOX2 axis.
Combined delivery of salinomycin and docetaxel by dual-targeting gelatinase nanoparticles effectively inhibits cervical cancer cells and cancer stem cells
Intra-tumor heterogeneity is widely accepted as one of the key factors, which hinders cancer patients from achieving full recovery. Especially, cancer stem cells (CSCs) may exhibit self-renewal capacity, which makes it harder for complete elimination of tumor. Therefore, simultaneously inhibiting CSCs and non-CSCs in tumors becomes a promising strategy to obtain sustainable anticancer efficacy. Salinomycin (Sal) was reported to be critical to inhibit CSCs. However, the poor bioavailability and catastrophic side effects brought about limitations to clinical practice. To solve this problem, we previously constructed gelatinase-stimuli nanoparticles composed of nontoxic, biocompatible polyethylene glycol-polycaprolactone (PEG-PCL) copolymer with a gelatinase-cleavable peptide Pro-Val-Gly-Leu-Iso-Gly (PVGLIG) inserted between the two blocks of the copolymer. By applying our "smart" gelatinase-responsive nanoparticles for Sal delivery, we have demonstrated specific accumulation in tumor, anti-CSCs ability and reduced toxicity of Sal-NPs in our previous study. In the present study, we synthesized Sal-Docetaxel-loaded gelatinase-stimuli nanoparticles (Sal-Doc NP) and confirmed single emulsion as the optimal method of producing Sal-Doc NPs (Sal-Doc SE-NP) in comparison with nanoprecipitation. Sal-Doc SE-NPs inhibited both CSCs and non-CSCs in mice transplanted with cervical cancer, and might be associated with enhanced restriction of epithelial-mesenchymal transition (EMT) pathway. Besides, the tumorigenic capacity and growing speed were obviously suppressed in Sal-Doc-SE-NPs-treated group in rechallenge experiment. Our results suggest that Sal-Doc-loaded gelatinase-stimuli nanoparticles could be a promising strategy to enhance antitumor efficacy and reduce side effects by simultaneously suppressing CSCs and non-CSCs.
Plasma‐Based Metabolomics Profiling of High‐Risk Human Papillomavirus and their Emerging Roles in the Progression of Cervical Cancer
High‐risk human papillomavirus (HR‐HPV) is the main etiological factor for cervical cancer. Accumulating evidence has suggested the active role of metabolites in the initiation and progression of cancers. This study explored the plasma metabolic profiles of HPV‐16 positive (HPV16 (+)), HPV‐18 positive (HPV18 (+)), and HPV negative (CTL) individuals using a nontargeted metabolomics approach. C8 ceramide‐1‐Phosphate (d18 : 1/8 : 0) was found to inhibit cervical cancer cell proliferation and migration in vitro, evidenced by CCK8 experiments, a cell migration test, RT‐qPCR, and western blotting. The underlying mechanism demonstrated that C8 inhibited proliferation and migration in cervical cancer cells via the MAPK/JNK1 signaling pathway. These findings may contribute to the clinical treatment of HR‐HPV‐induced cervical cancer by intervening in its initiation and progression.