Application progress of microfluidic chip in isolation and capture of circulating tumor cells / 中华检验医学杂志

The amount of circulating tumor cells(CTC) in peripheral blood is very small, which is difficult to isolate. Microfluidic chips are becoming a hot area in recent years because of their portability, high sensitivity, high capture,and low cost. Microfluidic devices have been shown to maintain optimal performance for CTC isolation capture, including flux, purity, recovery, and clinical relevance. However, microfluidic technology is still unable to recover CTC with high recovery and purity.

Circulating tumor cells-based model for pulmonary solid nodules diagnosis: a multicenter study / 中华胸心血管外科杂志

Objective:To evaluate the clinical radiological features combined with circulating tumor cells in the diagnosis of benign and malignant pulmonary solid nodules.Methods:Clinical data of 437 patients from Shanghai Pulmonary Hospital(SPH cohort) from January to April 2021 and 82 patients from Lanzhou University First Hospital (LZH cohort) from August 2019 to May 2022 were retrospectively included. Patients in Shanghai pulmonary hospital were randomly divided into training set and internal validation set in a ratio of 4∶1 by random number table method and patients in Lanzhou University First Hospital were as external validation set. Independent risk factors were selected by regression analysis of training set constructed a Nomogram prediction model. The performance of the Nomogram prediction model was estimated by applying receiver operating curve( ROC) analysis, tested in different nodules size and intermediate risk IPSNs and tested by calibration curve. Results:Independent risk factors selected by regression analysis for solid pulmonary nodules were age, the level of CTC, pleural Indentation, lobulation, spiculation. The Nomogram prediction mode provided an area under ROC( AUC) of 0.888, 0.833 in internal validation set and external validation set, outperforming radiological features model(0.835, P=0.007; 0.804, P=0.043) Mayo clinical model(0.781, P=0.019; 0.726, P=0.033) and CTCs(0.699, P=0.002; 0.648, P=0.012) in both two validation sets, C-index of 0.888, 0.871 and corrected C-index of 0.853, 0.842 in both two validation sets . The AUC of the prediction model with internal validation set was 0.905 and 0.871 for nodule diameter of 5-20 mm and intermediate risk probability. Conclusion:The prediction model in this study has better diagnostic value and practicability, and is more effective in clinical diagnosis of diseases.

Evaluation of anti-tumor effect of a novel manganese adjuvant collaborated with tumor antigens / 中国生物制品学杂志

@#ObjectiveTo investigate the anti-tumor effect of agonist MnCl_2of a novel cyclic guanosine monophosphate-adenosine monophosphate synthase(c GAS)/stimulator of interferon genes(STING)pathway collaborated with tumor cell lysate(Lysate)and the neo-antigen 10K-Adpgk of mouse colon cancer MC38 cell line.MethodsBone marrow-derived dendritic cells(BMDCs)were extracted from mouse bone marrow and divided into three groups:PBS,1 μmol/L MnCl_2and 10 μmol/L MnCl_2,which were analyzed for the maturation by flow cytometry,determined for the concentration of IL-6 in supernatant by ELISA,and detected for the transcription levels of IL-6,IFN-α,IFN β and CXCL9 genes by q PCR.Mouse tumor model was established by using MC38 cell line.When the tumor volume reached 100 mm3,the mice were randomly divided into two groups for administration,PBS,Lysate,MnCl_2,10K-Adpgk,Lysate + MnCl_2group and Lysate +10K-Adpgk + MnCl_2combined treatment group,which were administered subcutaneously through the tail for 3 times,with each interval of 1 week,and measured for the tumor volume every 2 days.One week after the last dose,serum samples were collected and determined for the concentrations of IFNγ and TNFα by ELISA.The tumor and spleen were isolated.The proportions of tumor infiltrating T cells and T cells in peripheral blood mononuclear cells(PBMCs)and the ratio of T cells to memory T cells in spleen were detected by flow cytometry,and the proportion of antigen specific T cells in spleen was detected by ELISPOT.Results10 μmol/L MnCl_2stimulated the maturation of BMDCs and activated the subsequent immune process.The tumor volumes of mice in the combined treatment group were considerably smaller than those in PBS group,the contents of IFNγ and TNF-α in serum were higher than those in other groups,and the proportions of tumor infiltrating T cells,T cells in PBMCs and ratio of T cells to memory T cells in spleen were also significantly higher than those in PBS group.Combined therapy caused strong antigen-specific T cell immune response.ConclusionThe addition of the novel adjuvant MnCl_2significantly enhanced the treatment effect of tumor cell lysate and neo-antigen,which provided an experimental basis for the development of the combination tumor treatment method based on MnCl_2and tumor antigens.

A metabolic intervention strategy to break evolutionary adaptability of tumor for reinforced immunotherapy

The typical hallmark of tumor evolution is metabolic dysregulation. In addition to secreting immunoregulatory metabolites, tumor cells and various immune cells display different metabolic pathways and plasticity. Harnessing the metabolic differences to reduce the tumor and immunosuppressive cells while enhancing the activity of positive immunoregulatory cells is a promising strategy. We develop a nanoplatform (CLCeMOF) based on cerium metal-organic framework (CeMOF) by lactate oxidase (LOX) modification and glutaminase inhibitor (CB839) loading. The cascade catalytic reactions induced by CLCeMOF generate reactive oxygen species "storm" to elicit immune responses. Meanwhile, LOX-mediated metabolite lactate exhaustion relieves the immunosuppressive tumor microenvironment, preparing the ground for intracellular regulation. Most noticeably, the immunometabolic checkpoint blockade therapy, as a result of glutamine antagonism, is exploited for overall cell mobilization. It is found that CLCeMOF inhibited glutamine metabolism-dependent cells (tumor cells, immunosuppressive cells, etc.), increased infiltration of dendritic cells, and especially reprogrammed CD8+ T lymphocytes with considerable metabolic flexibility toward a highly activated, long-lived, and memory-like phenotype. Such an idea intervenes both metabolite (lactate) and cellular metabolic pathway, which essentially alters overall cell fates toward the desired situation. Collectively, the metabolic intervention strategy is bound to break the evolutionary adaptability of tumors for reinforced immunotherapy.

Irregular-Shaped Fe3O4 Nanoparticles-Mediated Magneto-Mecha nical Force for Killing Tumor Cell / 医用生物力学

Objective To investigate tumor cell killing effect of superparamagnetic Fe3O4 nanoparticles with cubic phase through magneto-mechanical force under a low-frequency vibrating magnetic field ( VMF). Methods A kind of strong magnetic and irregular-shaped Fe3O4 nanoparticles with cubic phase was synthesized by coprecipitation method. The Fe3O4 nanoparticles were exposed to a self-developed VMF and cell killing efficiency of the Fe3O4-mediated magneto-mechanical force was investigated. Results VMF alone had no effects on cell viability. After Fe3O4 nanoparticles were added, the cell viability significantly decreased with prolonging the VMF treatment time and increasing the Fe3O4 nanoparticle concentration. Lactate dehydrogenase released by damaged cells also increased with prolonging the VMF exposure time. Conclusions The irregular-shaped Fe3O4 nanoparticles can transfer magneto-mechanical force to tumor cells under VMF, cause structural damage of cells and result in cell death. The VMF generator developed in this study has simple structure and it is safe for use and convenient for operation. The developed magnetic nanoparticles and the corresponding cancer cell killing technique have the potential for clinical transformation.

CD44-HA Mediate Adhesion of MDA-MB-231 Cells and HL60 Cells under Fluid Shear Flow / 医用生物力学

Objective To explore how hyaluronic acid ( HA) in extracellular matrix regulates the adhesion ofCD44+tumor cells. Methods MDA-MB-231 cells or HL60 cells were perfused in a parallel plate chamber. Themovement of cells over immobilized HA was observed and analyzed to obtain the characteristics of cell adhesionand rolling. Results The adhesion number of MDA-MB-231 cells on HA substrate was positively regulated by HAconcentration, but not by HA molecular weight. Compared with physically adsorbed HA, immobilized HA byavidin-biotin could significantly improve the cell adhesion ratio. With the increase of shear stress in the range of30-50 mPa, the rolling velocity of cells increased and the adhesion ratio decreased, but the tether lifetime of cellswas not affected. In the same flow field, compared with MDA-MB-231 cells, HL60 cells with low expression ofCD44 rolled more quickly on immobilized HA, with shorter tether lifetime and much lower adhesion ratio(<1. 5% ). Conclusions Fluid shear stress might mediate the rolling velocity of MDA-MB-231 cells by regulatingthe CD44-HA association rate rather than their dissociation rate. The interaction between CD44 and HA is involved in the initial adhesion of HL60 cells, but it does not play a major role. This study will provide references for the design of anti-tumor drugs.

Tumor cell lysate with low content of HMGB1 enhances immune response of dendritic cells against lung cancer in mice / 南方医科大学学报

OBJECTIVE@#To assess the effect of tumor cell lysate (TCL) with low high-mobility group B1 (HMGB1) content for enhancing immune responses of dendritic cells (DCs) against lung cancer.@*METHODS@#TCLs with low HMGB1 content (LH-TCL) and normal HMGB1 content (NH-TCL) were prepared using Lewis lung cancer (LLC) cells in which HMGB1 was inhibited with 30 nmol/L glycyrrhizic acid (GA) and using LLC cells without GA treatment, respectively. Cultured mouse DCs were exposed to different doses of NH-TCL and LH-TCL, using PBS as the control. Flow cytometry was used to detect the expressions of CD11b, CD11c and CD86 and apoptosis of the stimulated DCs, and IL-12 levels in the cell cultures were detected by ELISA. Mouse spleen cells were co-cultured with the stimulated DCs, and the activation of the spleen cells was assessed by detecting CD69 expression using flow cytometry; TNF-β production in the spleen cells was detected with ELISA. The spleen cells were then co-cultured with LLC cells at the effector: target ratios of 5:1, 10:1 and 20:1 to observe the tumor cell killing. In the animal experiment, C57/BL6 mouse models bearing subcutaneous LLC xenograft received multiple injections with the stimulated DCs, and the tumor growth was observed.@*RESULTS@#The content of HMGB1 in the TCL prepared using GA-treated LLC cells was significantly reduced (P < 0.01). Compared with NH-TCL, LH-TCL showed a stronger ability to reduce apoptosis (P < 0.001) and promote activation and IL- 12 production in the DCs. Compared with those with NH-TCL stimulation, the DCs stimulated with LH-TCL more effectively induced activation of splenic lymphocytes and enhanced their anti-tumor immunity (P < 0.05). In the cell co-cultures, the spleen lymphocytes activated by LH-TCL-stimulated DCs showed significantly enhanced LLC cell killing activity (P < 0.01). In the tumor-bearing mice, injections of LH-TCL-stimulated DCs effectively activated host anti-tumor immunity and inhibited the growth of the tumor xenografts (P < 0.05).@*CONCLUSION@#Stimulation of the DCs with LH-TCL enhances the anti-tumor immune activity of the DCs and improve the efficacy of DCbased immunotherapy for LLC in mice.

S100A10 promotes proliferation and invasion of lung adenocarcinoma cells by activating the Akt-mTOR signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of expression levels of S100 calcium-binding protein A10 (S100A10) in lung adenocarcinoma (LUAD) on patient prognosis and the regulatory role of S100A10 in lung cancer cell proliferation and metastasis.@*METHODS@#Immunohistochemistry was used to detect the expression levels of S100A10 in LUAD and adjacent tissues, and the relationship between S100A10 expression and clinicopathological parameters and prognosis of the patients was statistically analyzed. The lung adenocarcinoma expression dataset in TCGA database was analyzed using gene enrichment analysis (GSEA) to predict the possible regulatory pathways of S100A10 in the development of lung adenocarcinoma. Lactate production and glucose consumption of lung cancer cells with S100A10 knockdown or overexpression were analyzed to assess the level of glycolysis. Western blotting, CCK-8 assay, EdU-594 assay, and Transwell assays were performed to determine the expression level of S100A10 protein, proliferation and invasion ability of lung cancer cells. A549 cells with S100A10 knockdown and H1299 cells with S100A10 overexpression were injected subcutaneously in nude mice, and tumor growth was observed.@*RESULTS@#The expression level of S100A10 was significantly upregulated in LUAD tissues as compared with the adjacent tissues, and an elevated S100A10 expression level was associated with lymph node metastasis, advanced tumor stage and distant organ metastasis (P < 0.05), but not with tumor differentiation or the patients' age or gender (P > 0.05). Survival analysis showed that elevated S100A10 expressions in the tumor tissue was associated with a poor outcome of the patients (P < 0.001). In the lung cancer cells, S100A10 overexpression significantly promoted cell proliferation and invasion in vitro (P < 0.001). GSEA showed that the gene sets of glucose metabolism, glycolysis and mTOR signaling pathway were significantly enriched in high expressions of S100A10. In the tumor-bearing nude mice, S100A10 overexpression significantly promoted tumor growth, while S100A10 knockdown obviously suppressed tumor cell proliferation (P < 0.001).@*CONCLUSION@#S100A10 overexpression promotes glycolysis by activating the Akt-mTOR signaling pathway to promote proliferation and invasion of lung adenocarcinoma cells.

Tumor cell and microvessel densities during the growth of a brain tumor: A theoretical study

Mathematical model for the tumor growth incorporating energy supply and requirement, angiogenesis efficiency and effect of elasticity of adjacent normal tissue to understand tumor biology and predict saturation status is rare to find. This study is conducted to address these issues. We propose mathematical expressions to explain alterations of tumor cell density (nT), microvessel density (MVD), and growth rate(r) during the development of brain tumors. We assume that nT increases during the growth of the tumor due to the increase of external pressure from the initial cell density (nT0); nT0 is same as the external normal tissue. The rate of increase in tumor cells (dNT/dt) depends on the rate of energy available for the creation of new cells and the energy required for a single cell division(?). Due to the increase of tumor cell density, hypoxia is developed, which up-regulates the secretion of vascular endothelial growth factor (VEGF) and new capillaries are generated. Therefore, the surface area density of capillaries (Acs) in tumors increases. Hence, we consider that Acs(t) ? nT(t). A modified logistic equation is developed. Temporal variations of nT(t), Acs(t), r(t) and tumor cell population ‘NT(t)’ are examined. The expressions of saturated cell density(nTM), saturated microvessel surface area density (AcsM) and tumor saturation time(Ts) are formulated. An important feature, tumor saturation factor ‘fTS’ is determined. When fTS<1, a tumor will saturate at Ts, and nTM depends solely on fTS.

Recent clinical research on the application of liquid biopsy in neuroblastoma / 中国当代儿科杂志

Neuroblastoma (NB) is the most common extracranial solid tumor in children and has the features of high recurrence rate and low survival rate, and therefore, early diagnosis, treatment response evaluation, and recurrence monitoring are of great significance for NB patients. Liquid biopsy refers to the detection of cells and nucleic acids in fluid specimens, mainly blood. It is noninvasive and can overcome tumor heterogeneity, thus making it possible to achieve the early diagnosis and dynamic detection of NB. This review introduces the latest advances in clinical research on the application of liquid biopsy in NB.

Application value of peripheral blood circulating tumor cell classification in the prediction of preoperative microvascular invasion of hepatocellular carcinoma / 中华消化外科杂志

Objective:To investigate the application value of peripheral blood circulating tumor cell (CTC) classification in the prediction of preoperative microvascular invasion of hepato-cellular carcinoma (HCC).Methods:The retrospective case-control study was conducted. The clinico-pathological data of 102 HCC patients who were admitted to Zhengzhou University People's Hospital from September 2018 to September 2020 were collected. There were 71 males and 31 females, aged from 29 to 80 years, with a median age of 57 years. Observation indicators: (1) surgical situations; (2) results of CTC detection and microvascular invasion in HCC patients; (3) results of CTC classification and the best cut-off value of CTC classification in the prediction of microvascular invasion in HCC; (4) influencing factors for microvascular invasion in HCC; (5) comparison of clinicopathological features in HCC patients with different cell counts in mesenchymal phenotype of CTC (M-CTC). Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the independent sample t test. Measurement data with skewed distribution were represented as M(range) or M( Q1, Q3), and comparison between groups was analyzed using the nonparametric rank sum U test. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. The receiver operating characteristic (ROC) curve was used to determine the best cut-off value for the risk of microvascular invasion in patients. Univariate and multivariate analysis were performed using the Logistic regression model. Results:(1) Surgical situations. All 102 patients underwent surgery successfully, including 17 cases undergoing local hepatectomy, 43 cases under-going segmentectomy, 22 cases undergoing hepatic lobectomy, 13 cases undergoing hemilectomy and 7 cases undergoing enlarged hemilectomy. The operation time and the volume of intraoperative blood loss were 235(147,293)minutes and 300(110,500)mL of the 102 patients, respectively. (2) Results of CTC detection and microvascular invasion in HCC patients. Of 102 patients, there were 36 casas with epithelial phenotype of CTC (E-CTC), 86 cases with hybrid phenotype of CTC (H-CTC), 30 cases with M-CTC, respectively, and the total CTC (T-CTC) were positive in 89 cases. Results of postoperative pathological examination showed that there were 40 cases with micro-vascular inva-sion and 62 cases without microvascular invasion in the 102 patients. Of the 40 patients with micro-vascular invasion, the count of E-CTC, H-CTC, M-CTC and T-CTC were 0(0,1) per 5 mL, 4(2,5) per 5 mL, 1(0,2) per 5 mL and 5(3,8) per 5mL, respectively. The above indicators of the 62 cases without microvascular invasion were 0(0,1) per 5 mL, 3(1,5) per 5 mL, 0(0,0) per 5 mL and 3(2,6) per 5 mL, respectively. There were significant differences in the count of M-CTC and T-CTC between patients with and without microvascular invasion ( Z=-4.83, -2.96, P<0.05). (3) Results of CTC classi-fication and the best cut-off value of CTC classification in the prediction of microvascular invasion in HCC. The ROC curve showed that best cut-off value of M-CTC and T-CTC counts in the prediction of microvascular invasion in HCC were 1 per 5 mL and 4 per 5 mL, respectively, with the area under curve, the corresponding specificity, sensitivity were 0.70 (95% confidence interval as 0.60-0.81, P<0.05), 75.8%, 62.9% and 0.67 (95% confidence interval as 0.57-0.78, P<0.05), 60.0%, 72.5%, respec-tively. (4) Influencing factors for microvascular invasion in HCC. Result of univariate analysis showed that alpha fetoprotein (AFP), aspartate aminotransferase (AST), tumor diameter, tumor number, tumor margin, Barcelona clinic liver cancer staging, M-CTC counts and T-CTC counts were related factors influencing microvascular invasion in HCC ( odds ratio=3.13, 0.43, 4.92, 5.65, 2.54, 2.93, 8.25, 4.47, 95% confidence interval as 1.34-7.33, 0.19-0.98, 2.09-11.58, 2.35-13.63, 1.13-5.75, 1.27-6.74, 3.13-21.75, 1.88-10.61, P<0.05). Result of multivariate analysis showed that tumor diameter >5 cm, tumor number as multiple and M-CTC counts ≥1 per 5 mL were independent risk factors influencing microvascular invasion in HCC ( odds ratio=2.97, 4.14, 4.36, 95% c onfidence interval as 1.01-8.70, 1.14-15.02, 1.36-13.97, P<0.05). (5) Comparison of clinicopathological features in HCC patients with different cell counts in M-CTC. The 102 HCC patients were divided into the high M-CTC group of 30 cases with M-CTC counts ≥1 per 5 mL and the low M-CTC group of 72 cases with M-CTC counts <1 per 5 mL, according to the best cut-off value of M-CTC counts. Cases with hepatitis, cases with AFP >400 μg/L, cases with AST >35 U/L, cases with irregular tumor margin, cases with tumor diameter >5 cm, cases with tumor number as multiple and cases with micro-vascular invasion were 22, 17, 13, 21, 18, 16 and 22 in the high M-CTC group of 30 cases. The above indicators were 35, 18, 48, 26, 25, 21 and 18 in the low M-CTC group of 72 cases. There were significant differences in the above indicators between the high M-CTC group and the low M-CTC group ( χ2=5.25, 9.42, 4.80, 9.79, 5.55, 5.35, 20.75, P<0.05). Conclusions:The epithelial-mesen-chymal phenotype of peripheral blood CTC can be used to predict the preoperative microvascular invasion in HCC. Tumor diameter >5 cm, tumor number as multiple and M-CTC counts ≥1 per 5 mL are independent risk factors influencing microvascular invasion in HCC patients.

Research Progress of PD-L1 Expression in Circulating Tumor Cells in Malignant Tumors / 肿瘤防治研究

In recent years, with the in-depth study of PD-1 and PD-L1 and the development of immunotherapy, the first problem is how to screen the beneficiaries. Recent clinical studies have shown that the expression level of PD-L1 in circulating tumor cells (CTC) can be used as a potential biomarker to play a guiding role in immunotherapy of malignant tumors. This article reviews the latest clinical research progress on the expression of PD-L1 in circulating tumor cells in various solid tumors.

Circulating tumor cells in the diagnosis and treatment of early and advanced prostate cancer / 中华男科学杂志

Circulating tumor cells (CTC) are tumor cells that escape from the primary or metastatic tumor into the circulatory system, and closely related to cancer metastasis. Since the samples can be obtained through simple and minimally invasive blood sampling operations, CTCs have a great clinical potential. PCa is one of the most common malignant tumors in men. In recent years, many scholars have conducted studies as to whether CTC technology can be used for the diagnosis and treatment of PCa, as well as for more accurate prediction of the risk of progression. This article summarizes the advances in researches relating CTC technology and the diagnosis and treatment of PCa. CTC detection has been developed from simple counting to phenotypic classification, and even to its combination with the determination of the expressions of specific genes (such as AR, AR-V7, etc.) and single-cell sequencing. Some reports showed that CTC technology has a certain significance in the early diagnosis of PCa, but its main value is demonstrated in drug sensitivity and prognosis evaluation in the late stage of the malignancy. The standardized detection methods and reference values of CTCs in PCa will be important research orientations in the near future.

stablishment of a diagnostic model for clinical stage Ⅰ non-small cell lung cancer: A study based on clinical imaging features combined with folate receptor-positive circulating tumor cells tests / 中国胸心血管外科临床杂志

@#Objective    To analyze the correlation between folate receptor-positive circulating tumor cells (FR+CTC) and the benign or malignant lesions of the lung, and to establish a malignant prediction model for pulmonary neoplasm based on clinical data, imaging and FR+CTC tests. Methods    A retrospective analysis was done on 1 277 patients admitted to the Affiliated Hospital of Qingdao University from September 2018 to December 2019, including 518 males and 759 females, with a median age of 57 (29-85) years. They underwent CTC examination of peripheral blood and had pathological results of pulmonary nodules and lung tumors. The patients were randomly divided into a trial group and a validation group. Univariate and multivariate analyses were performed on the data of the two groups. Then the nomogram prediction model was established and verified internally and externally. Receiver operating characteristic (ROC) curve was used to test the differentiation of the model and calibration curve was used to test the consistency of the model. Results    Totally 925 patients suffered non-small cell lung cancer and 113 patients had benign diseases in the trial group; 219 patients suffered non-small cell lung cancer and 20 patients had benign diseases in the verification group. The FR+CTC in the peripheral blood of non-small cell lung cancer patients was higher than that found in the lungs of the patients who were in favorite conditions (P<0.001). Multivariate analysis showed that age≥60 years, female, FR+CTC value>8.7 FU/3 mL, positive pleural indenlation sign, nodule diameter, positive burr sign, consolidation/tumor ratio<1 were independent risk factors for benign and malignant lung tumors with a lesion diameter of ≤4 cm. Thereby, the nomogram prediction model was established. The area under the ROC curve (AUC) of the trial group was 0.918, the sensitivity was 86.36%, and the specificity was 83.19%. The AUC value of the verification group was 0.903, the sensitivity of the model was 79.45%, and the specificity was 90.00%, indicating nomogram model discrimination was efficient. The calibration curve also showed that the nomogram model calibration worked well. Conclusion    FR+CTC in the peripheral blood of non-small cell lung cancer patients is higher than that found in the lungs of the patients who carry benign pulmonary diseases. The diagnostic model of clinical stage Ⅰ non-small cell lung cancer established in this study owns good accuracy and can provide a basis for clinical diagnosis.

Simulation and Analysis of Capture Characteristics of Circulating Tumor Cells Based on Unidirectional Fluid-Solid Interaction Method / 医用生物力学

Objective To study movement process of circulating tumor cells (CTCs) in the blood and mechanism of CTC capture by CellCollector, and reveal relationship between the detected CTC numbers and the actual CTC concentration in the body. Methods Based on Fluent and EDEM software, the unidirectional fluid-solid interaction method was applied to establish a two-phase flow model, including the hemodynamic model and the CTC transport model, and capture simulations under different CTC concentration conditions were conducted. Results The number of CTCs captured by CellCollector was significantly positively correlated with the CTC concentration in the body. When the CTC concentration was low, CTCs could only be captured in several time intervals, and the capture had a certain contingency; as the concentration increased, the uniformity of CTC capture over time became better, and the total number of captures also increased. Conclusions Through the fitting of simulation results, analytical quantitative relationship between the captured CTC number and the CTC concentration in the body is preliminarily given, which provides theoretical basis and mechanical explanation for the clinical use of CellCollector.

Influences of Cell-ECM Adhesion on Migration of Tumor Cells Regulated by ECM Stiffness: A Model Study / 医用生物力学

Objective To study the influence of cell-extracellular matrix (ECM) adhesion on migration of tumor cells regulated by ECM stiffness. Methods The cellular Potts model (CPM) was established to simulate tumor cell growth and cellular immune feedback system. The effects from mechanical behavior of cells on cell-ECM adhesion were observed, and the migration of tumor cells under different ECM was analyzed. Results The ECM stiffness could influence the migration rate of tumor cells. The change of ECM stiffness regulated the adhesion force between cells and ECM, and the change of adhesion force would influence the migration rate of cells. Conclusions The migration and distribution patterns of cells are closely related to the adhesion and stiffness of ECM. The increase in ECM stiffness can effectively promote the migration rate of tumor cells, and the further increase in ECM stiffness inhibits the migration of tumor cells. These findings may further reveal dynamic changes of ECM, adhesion and mechanical performance of tumor cell migration.

Current status and future of drugs targeting platelets-tumor cells interactions / 药学学报

The interaction between platelets and tumor cells can not only promote the metastasis of malignant tumors, but also affect the formation of malignant tumor-related thrombus. When tumor cells enter the blood, they will immediately activate platelets to make them adhere to the surface of tumor cells, protecting tumor cells from blood flow shear force and immune system attack, thereby promoting tumor metastasis. At the same time, the massive adhesion of platelets may also lead to the formation of thrombus. In this article, we use the methods of ingenuity pathway analysis and literature integration to explore the mechanism of platelet-tumor cell interaction and potential drugs for the treatment of malignant tumor metastasis based on the platelet-tumor cell interaction. It provides a certain theoretical basis and clinical reference for the future development of new drugs targeting platelet-tumor cell interaction based on its mechanism of action.

Immune Mechanism of Tumor Cell Lysate Combined with IL-2 Preventing Melanoma and Inhibiting Tumor Growth / 肿瘤防治研究

Objective To investigate the preventive and inhibitory effects of tumor cell lysate(TCL) combined with IL-2 on melanoma and the potential immune mechanism. Methods The B16F10 melanoma TCL cell were prepared using an ultrasonic disruptor. Twenty-four C57BL/6 mice were randomly divided into four groups which were immunized with PBS, IL-2, TCL and TCL+IL-2 for three weeks, and contra lateral tumors were implanted in the fourth week. We observed onset time of tumor and tumor size, collected peripheral blood continuously and monitored the expression of CD4+T and CD8+T cell subsets dynamically by flow cytometry. Spleen and tumor tissues of mice were also tested for CD4+T and CD8+T cell subsets by flow cytometry and immunohistochemistry, respectively. Results The preventive immunization of the TCL+IL-2 group significantly delayed the onset time of tumor (P=0.034); moreover, the tumor volume (P=0.023) and tumor weight (P=0.0015) were also significantly smaller than those in the control group. The expression of CD8+T cell subsets in the TCL+IL-2 group and the TCL-only group were significantly higher than that in the control group (P=0.0016, P=0.012). However, the CD4+T cell subsets of the TCL+IL-2 group decreased after tumor implantation, compared with the control group (P=0.0089). The expression of CD4+T and CD8+T cell subsets in spleen and tumor tissues were as same as those in peripheral blood. Conclusion The tumor vaccine of TCL combined with IL-2 could prevent the occurrence of melanoma in mouse and effectively inhibit tumor growth by activating CD8+T cells.

Cancer-specific calcium nanoregulator suppressing the generation and circulation of circulating tumor cell clusters for enhanced anti-metastasis combinational chemotherapy

Tumor metastasis is responsible for chemotherapeutic failure and cancer-related death. Moreover, circulating tumor cell (CTC) clusters play a pivotal role in tumor metastasis. Herein, we develop cancer-specific calcium nanoregulators to suppress the generation and circulation of CTC clusters by cancer membrane-coated digoxin (DIG) and doxorubicin (DOX) co-encapsulated PLGA nanoparticles (CPDDs). CPDDs could precisely target the homologous primary tumor cells and CTC clusters in blood and lymphatic circulation. Intriguingly, CPDDs induce the accumulation of intracellular Ca

Preparation of curcumin TPP-PEG-PE nanomicelles with mitochondrial targeting and lysosomal escape functions and its effect on promoting breast cancer cell apoptosis / 中国中药杂志

Orthogonal experiments were used to optimize the process parameters of curcumin TPP-PEG-PCL nanomicelles; the particle size, electric potential and morphology under the electron microscope were systematically detected for the curcumin TPP-PEG-PCL nanomicelles; and the stability and in vitro release of the curcumin TPP-PEG-PCL nanomicelles were investigated. With DID fluorescent dye as the fluorescent probe, flow cytometry was used to study the uptake of nanomicelles by breast cancer cells, and laser confocal microscopy was used to study the mitochondrial targeting and lysosomal escape functions of nanomicelles. Under the same dosage conditions, the effect of curcumin TPP-PEG-PCL nanomicelles on promoting the apoptosis of breast cancer cells was evaluated. The optimal particle size of curcumin TPP-PEG-PCL nanomicelle was(17.3±0.3) nm, and the Zeta potential was(14.6±2.6) mV in orthogonal test. Under such conditions, the micelle appeared as regular spheres under the transmission electron microscope. Fluorescence test results showed that TPP-PEG-PCL nanomicelles can promote drug uptake by tumor cells, escape from lysosomal phagocytosis, and target the mitochondria. The cell survival rate and Hoechst staining positive test results showed that curcumin TPP-PEG-PCL nanomicelles had a good effect on promoting apoptosis of breast cancer cells. The curcumin TPP-PEG-PCL micelles can significantly reduce the mitochondrial membrane potential of breast cancer cells, increase the release of cytochrome C, significantly increase the expression of pro-apoptotic protein Bcl-2 and reduce the expression of anti-apoptotic Bax protein. These test results were significantly better than those of curcumin PEG-PCL nanomicelles and curcumin, with statistically significant differences. The results revealed that curcumin TPP-PEG-PCL nanomicelles can well target breast cancer cell mitochondria and escape from the lysosomal capture, thereby enhancing the drug's role in promoting tumor cell apoptosis.