Serum Of Nude Mice Research Articles

Physical exercise suppresses hepatocellular carcinoma progression by alleviating hypoxia and attenuating cancer stemness through the Akt/GSK-3β/β-catenin pathway

ObjectivePhysical exercise, a common non-drug intervention, is an important strategy in cancer treatment, including hepatocellular carcinoma (HCC). However, the mechanism remains largely unknown. Due to the importance of hypoxia and cancer stemness in the development of HCC, the present study investigated whether the anti-HCC effect of physical exercise is related to its suppression on hypoxia and cancer stemness. MethodsA physical exercise intervention of swimming (30 min/d, 5 d/week, for 4 weeks) was administered to BALB/c nude mice bearing subcutaneous human HCC tumor. The anti-HCC effect of swimming was assessed in vivo by tumor weight monitoring, hematoxylin and eosin (HE) staining, and immunohistochemistry (IHC) detection of proliferating cell nuclear antigen (PCNA) and Ki67. The expression of stemness transcription factors, including Nanog homeobox (NANOG), octamer-binding transcription factor 4 (OCT-4), v-Myc avian myelocytomatosis viral oncogene homolog (C-MYC) and hypoxia-inducible factor-1α (HIF-1α), was detected using real-time reverse transcription polymerase chain reaction. A hypoxia probe was used to explore the intratumoral hypoxia status. Western blot was used to detect the expression of HIF-1α and proteins related to protein kinase B (Akt)/glycogen synthase kinase-3β (GSK-3β)/β-catenin signaling pathway. The IHC analysis of platelet endothelial cell adhesion molecule-1 (CD31), and the immunofluorescence co-location of CD31 and desmin were used to analyze tumor blood perfusion. SMMC-7721 cells were treated with nude mice serum. The inhibition effect on cancer stemness in vitro was detected using suspension sphere experiments and the expression of stemness transcription factors. The hypoxia status was inferred by measuring the protein and mRNA levels of HIF-1α. Further, the expression of proteins related to Akt/GSK-3β/β-catenin signaling pathway was detected. ResultsSwimming significantly reduced the body weight and tumor weight in nude mice bearing HCC tumor. HE staining and IHC results showed a lower necrotic area ratio as well as fewer PCNA or Ki67 positive cells in mice receiving the swimming intervention. Swimming potently alleviated the intratumoral hypoxia, attenuated the cancer stemness, and inhibited the Akt/GSK-3β/β-catenin signaling pathway. Additionally, the desmin+/CD31+ ratio, rather than the number of CD31+ vessels, was significantly increased in swimming-treated mice. In vitro experiments showed that treating cells with the serum from the swimming intervention mice significantly reduced the formation of SMMC-7721 cell suspension sphere, as well as the mRNA expression level of stemness transcription factors. Consistent with the in vivo results, HIF-1α and Akt/GSK-3β/β-catenin signaling pathway were also inhibited in cells treated with serum from swimming group. ConclusionSwimming alleviated hypoxia and attenuated cancer stemness in HCC, through suppression of the Akt/GSK-3β/β-catenin signaling pathway. The alleviation of intratumoral hypoxia was related to the increase in blood perfusion in the tumor.Please cite this article as: Xiao CL, Zhong ZP, Lü C, Guo BJ, Chen JJ, Zhao T, Yin ZF, Li B. Physical exercise suppresses hepatocellular carcinoma progression by alleviating hypoxia and attenuating cancer stemness through the Akt/GSK-3β/β-catenin pathway. J Integr Med. 2023; 21(2): 184–193.

A dual-signal amplification strategy based on pump-free SERS microfluidic chip for rapid and ultrasensitive detection of non-small cell lung cancer-related circulating tumour DNA in mice serum

Circulating tumour DNAs (ctDNAs) have been reported to be associated with real-time information of progression; however, an accurate and sensitive method has not been established. Herein, a novel dual-signal amplification strategy based on a pump-free surface-enhanced Raman scattering (SERS) microfluidic chip and a catalytic hairpin assembly (CHA) technique was developed for the dynamic monitoring of BRAF V600E and KRAS G12V, which are two non-small cell lung cancer (NSCLC)-related ctDNAs. In the presence of targets, CHA reactions can be triggered between two hairpin DNAs, fixing Pd-Au core-shell nanorods (Pd-AuNRs) onto the magnetic beads (MBs) surface. Thereafter, the composite structures can assemble under the action of magnet, enabling dual-amplification of SERS signal. Using this strategy, the limit of detection (LOD) was low (i.e. at the aM level) in serum. Furthermore, the entire chip-based analysis process could be completed within 5 min, eliminating manual incubation and heavy-duty injection pumps. The selectivity, reproducibility and uniformity of the proposed pump-free SERS microfluidic chip were satisfactory. This superior analysis strategy was finally applied to quantify BRAF V600E and KRAS G12V in tumour-bearing nude mice serum, the results of which corresponded with those of real-time polymerase chain reaction. Overall, this study provides a promising alternative tool for the dynamic monitoring of ctDNA expression level which can benefit the clinical diagnosis of NSCLC.

Role of vitronectin-rich protein corona on tumor-specific siRNA delivery and transfection with lipid nanoparticles.

Aim: To evaluate the role of vitronectin-enriched protein corona on systemic delivery of siRNA-encapsulated cationic lipid nanoparticles (LNPs) to αvβ3 integrin expressing solid tumors. Materials & methods: 1,2-Dioleoyl-3-trimethylammonium-propaneLNPs were formulated, protein corona formed in nude mice serum and its impact on drug delivery were analyzed. Results: 1,2-Dioleoyl-3-trimethylammonium-propane-containing LNP led to enhanced recruitment of vitronectin and showed preferential transfection to αvβ3-expressed cells relative to controls. Upon systemic administration in mice, the LNPs accumulated in the αvβ3-expressing endothelial lining of the tumor blood vessels before reaching tumor cells. Conclusion: These results present an optimized LNP that selectively recruits endogenous proteins in situ to its corona which may lead to enhanced delivery and transfection in tissues of interest.

Psychological Stress Up-Regulates CD147 Expression Through Beta-Arrestin1/ERK to Promote Proliferation and Invasiveness of Glioma Cells.

Psychological stress is closely related to the occurrence and prognosis of various malignant tumors, but the underlying mechanisms are not well studied. CD147 has been reported to be expressed in glioma and other malignant tumors. CD147 not only participates in lactic acid transport, but it also plays an important role in the invasion and metastasis of malignant tumor cells by stimulating the production of numerous matrix metalloproteinases (MMPs) and vascular endothelial growth factor by fibroblasts, and could also act as an autocrine factor stimulating MMPs production in metastatic tumor cells. Here, we found that silencing CD147 in chronically stressed nude mice not only inhibited the proliferation of xenografts but also decreased matrix metalloproteinase-2, 9 expression and lactic acid content in tumor tissues. Furthermore, norepinephrine (NE) was significantly increased in the serum of nude mice in glioma stress model. To determine the underlying cellular mechanism, we added exogenous NE into LN229 and U87 cells to simulate the stress environment in vitro. The invasiveness of the glioma cells was subsequently examined using a Matrigel invasion assay. We demonstrated that knockdown of CD147 inhibited glioma invasiveness and metastasis with norepinephrine stimulation. Luciferase reporter gene experiments further demonstrated that the expression of CD147 is up-regulated primarily by norepinephrine via the β-Adrenalin receptor (βAR)-β-arrestin1-ERK1/2-Sp1 pathway. High expression of CD147 promoted the secretion of MMP-2 and the increment of lactic acid, which accelerated the augmented invasion and metastasis of glioma induced by psychological stress. Taken together, these results suggest that psychological stress promotes glioma proliferation and invasiveness by up-regulating CD147 expression. Thus, CD147 might be a potential target site in the treatment of glioma progression induced by chronic psychological stress.

Low-dose naltrexone inhibits the epithelial-mesenchymal transition of cervical cancer cells in vitro and effects indirectly on tumor-associated macrophages in vivo

The metastasis of cervical cancer has always been a clinical challenge. We investigated the effects of low-dose naltrexone (LDN) on the epithelial mesenchymal transition of cervical cancer cells in vitro as well as its influence on macrophage polarization and associated cytokines in vivo. The results suggested that LDN supressed the proliferation, migration and invasion abilities and promote their apoptosis in Hela cells, whereas the opioid growth factor receptor (OGFr) silenced significantly reversed these effects in vitro. Knockdown the expression of OGFr, the inhibitory of LDN on EMT was weakened. LDN could inhibit cervical cancer progression in nude mice. In additon, LDN indirectly reduced the number of tumor-associated macrophages (TAMs), mainly M2 macrophages, and decreased expression of anti-inflammatory factor IL-10 in the serum of nude mice. These findings demonstrate that LDN could be a potential treatment for cervical cancer.

Long non-coding RNA HAGLROS regulates lipid metabolism reprogramming in intrahepatic cholangiocarcinoma via the mTOR signaling pathway

Alternation of long non-coding RNA (lncRNA) is implicated in intrahepatic cholangiocarcinoma (ICC) development. HAGLROS is a lncRNA with a length of 699 bp, which is involved in the progression of various cancers. But the mechanism of HAGLROS in ICC remains unknown. In this study, the sh-HAGLROS-1 or sh-HAGLROS-2 was transfected into QBC939 cells, and overexpressing HAGLROS vector was transfected into KMCH cells. HAGLROS expression in ICC tissues and cell lines was detected, and its association with ICC prognosis was further analyzed. Lipid accumulation and lipid-related indicators (TG, LDL-C, TC and HDLC) in QBC939 and KMCH cells were measured. ICC cell viability, invasion and migration were measured. Western blot analysis was used to detect levels of the mTOR axis-related proteins and autophagy-related proteins (LC3I, LC3II, Beclin and P62). The levels of serum lipids and SREBP1 positive expression in transplanted tumors of nude mice were detected. HAGLROS was highly expressed in ICC and negatively correlated with prognosis. QBC939 cells with knocking down HAGLROS exhibited reduced lipid-related protein levels, blocked ICC cellular processes, inactivated mTOR axis, and increased autophagy. QBC939 cells with overexpressing HAGLROS showed opposite trends. The lipid-related protein levels in serum of nude mice and SREBP1 positive expression in transplanted tumors were diminished. Taken together, sh-HAGLROS inactivated the mTOR axis and promoted autophagy, thereby improving lipid metabolism reprogramming in ICC. This study may offer novel ICC treatments.

Inhibitory effect of Siwei Xiaoliuyin on glioma angiogenesis in nude mice.

Application of Siwei Xiaoliuyin in glioma mice. Explore the effect of Siwei Xiaoliuyin on angiogenesis of nude mice glioma and its mechanism. Establish human glioma cell line U87 tumor model. Mice were randomized to the saline group, the conventional dose of Siwei Xiaoliuyin, high dose group of Siwei Xiaoliuyin, TMZ group, combination therapy group, record the tumor volume. Using the method of Weidner counted the microvessel density. ELISA enzyme-linked adsorption method to detect the content of nude mice serum VEGF and ES. The difference was statistically significant (P<0.05). The tumor volume and MVD of conventional dose group, large dose group, Siwei Xiaoliuyin combined temozolomide group was smaller than the blank group，the difference was statistically significant (P<0.05). VEGF levels in three groups of nude mice were lower than the blank group and ES content is higher than blank group, the difference was statistically significant (P<0.05). Siwei Xiaoliuyin can inhibit glioma angiogenesis. Its mechanism of glioma angiogenesis inhibition may be through regulation VEGF and down-regulation of endostatin expression of vascular endothelial growth factor achieved. Down-regulation of endostatin expression of vascular endothelial growth factor achieved.

TNF-α derived from M2 tumor-associated macrophages promotes epithelial-mesenchymal transition and cancer stemness through the Wnt/β-catenin pathway in SMMC-7721 hepatocellular carcinoma cells

M2-polarized tumor-associated macrophages (M2-TAMs) infiltrating the tumor microenvironment contribute to hepatocellular carcinoma (HCC) progression. It was reported that cancer cells undergoing EMT will acquire stemness characteristics. Here, the HCC SMMC-7721 cell line was co-cultured with M2-TAMs polarized from THP-1 cells in vitro. In in vivo studies, we used nude mice subcutaneous tumor model to test whether the growth of the tumor was affected by M2-TAMs. Subsequently, EMT, stemness and Wnt/β-catenin pathway related markers were detected in cells and subcutaneous tumor tissues. TNF-α was also assessed in both the co-culture system supernatants and in nude mice serum. We found that SMMC-7721 underwent EMT and acquired stemness after co-culture with M2-TAMs, and resulted in larger tumor size following subcutaneous injection of SMMC-7721 suspended in M2-TAMs supernatants compared with SMMC-7721 alone. Enzyme linked immunosorbent assay showed that TNF-α expression was elevated in supernatants of M2-TAMs and positively correlated with tumor size in the serum of nude mice. Furthermore, we found that the Wnt/β-catenin pathway was a downstream target of TNF-α and that the Wnt/β-catenin inhibitor ICG-001 partially reversed EMT and attenuated cancer stemness. Our results indicate that TNF-α derived from M2-TAMs promote EMT and cancer stemness cells via the Wnt/β-catenin pathway.

The expression of miR-424*in vivo and in vitro irradiated A549 cells, tissue and serum samples of non-small cell lung cancer

Objective To investigate the expression of miR-424* in 2 and 4 Gy X-ray irradiated A549 cells in vitro and in vivo, as well as in clinical lung tissues and serum sample of non-small cell lung cancer(NSCLC) patients, and to explore its potential role in the diagnosis and prognosis of lung cancer. Methods A549 cells were irradiated with 2 and 4 Gy X-rays, and some of irradiated cells were injected into nude mice through tail vein. Real time quantitative PCR (RT-qPCR) assay was employed to detect the expression of miR-424* in 2 and 4 Gy X-ray irradiated A549 cells in vitro and in vivo, as well as in clinical lung tissues and serum sample of lung cancer patients. Results Compared with the control group, the expression of miR-424* was up-regulated significantly in X-ray irradiated A549 cells at 1, 2, 12, 24 and 48 h post irradiation, respectively (2 Gy: t=-45.886--6.709, P<0.05; 4 Gy: t=-29.087--7.833, P<0.05). Furthermore, the expression of miR-424* was up-regulated in the lung and serum of nude mice with injection of 0, 2 and 4 Gy X-ray irradiated A549 cells, compared with control group (fold change was 9.72, 8.58 and 4.7 with 2 Gy irradiation and 11.93, 9.22 and 8.99 with 4 Gy irradiation, t=-13.243, -12.409, -9.833 in lung and t=-6.436, -3.052, -3.609 in serum, respectively, P<0.05). Out of 11 tissue samples of NSCLC patients, 6 were detected with up-regulated miR-424* expression, and no significant discrepancy of miR-424* expression was detected in two type of NSCLC tissue samples. On the contrary, 43 serum samples were detected with up-regulated miR-424* expression out of 84 serum samples (51.20%) of NSCLC patients (fold change range 1.97 to 17.71), and significant discrepancy of miR-424* expression was shown in two subtypes of NSCLC serum samples [adenocarcinoma: 39.10% (18/46) and squamous carcinoma: 65.8% (25/38)], as well as in serum samples of NSCLC patients with radiotherapy [41.5% (22/53)] and without radiotherapy [67.7% (21/31)] (t=5.919, 5.387, P<0.05, respectively). Conclusions 2 and 4 Gy X-ray irradiation could up-regulate the expression of miR-424* in A549 cells, which might be correlated with the enhanced metastasis of A549 cells induced by X-ray in vivo and in vitro. Furthermore, the expression of miR-424* was up-regulated in over 50% of the tissue and serum samples of NSCLC patients, which might be correlated with the diagnosis of NSCLC subtype and prognosis of radiotherapy. Key words: Non-small cell lung cancer (NSCLC); miR-424*; Irradiation; microRNA

In vivo anti-tumor effect and in vitro anti-angiogenic effect of alcohol extract from Euphorbia prostrata

The study was designed to investigate the anti-tumor and anti-angiogenic effects of alcohol extract from Euphorbia prostrata. The alcohol extract of E. prostrata was prepared, and the tolerated dosage was determined in mice by the test for acute toxicity. Then, MTT method was used to study the anti-proliferation effect of E. prostrata on normal cells and tumor cells. The rat aortic endothelial cells(RAECs) were primarily cultured. Subsequently, in vitro cell proliferation, migration and tubule formation assays were performed to detect the effect of alcohol extract of E. prostrata on proliferation, migration and angiogenesis. Western blot analysis was performed to detect the protein expressions of Akt, p-Akt, eNOS, p-eNOS, TGF-β1 and Smad3 in RAECs treated with E. prostrata. In addition, an in vivo transplanted hepatocellular carcinoma model in nude mice was established to detect nude mass, tumor volume and tumor weight. The contents of vascular endothelial growth factor(VEGF) and the platelet-derived growth factor-BB(PDGF-BB) in blood serum were detected by using ELISA kits. HE staining was performed to study the morphology of tumor tissues. The tolerated dosage of alcohol extract of E. prostrata in mice was 94.29 g•kg⁻¹. Alcohol extract of E. prostrata showed no inhibitory effect on L6 cells, but significantly inhibited the proliferations of HepG-2, PC12, A549, and Hela cells with the following order： HepG-2>Hela>PC12>A549. Meanwhile, alcohol extract of E. prostrata markedly inhibited the proliferation, migration and tube formation of RAECs, and enhanced the expressions of phosphorylated Akt and eNOS and increased the expressions of TGF-β1 and Smad3. In addition, E. prostrata notably inhibited the tumor growth in mice, and decreased the amount of VEGF, but increased the amount of PDGF-BB factor in serum of nude mice. The alcohol extract of E. prostrata may show an inhibitory effect on tumor growth and angiogenesis, which may contribute to its anti-tumor effect.

Anticarcinogenic effects of water extract of sporoderm-broken spores of Ganoderma lucidum on colorectal cancer in vitro and in vivo.

Ganoderma lucidum (G. lucidum) polysaccharides (GLPs) have been used as traditional Chinese medicine for cancer prevention for many years. However, the mechanism by which GLP exerts its chemopreventive activities remains elusive. In addition, it is unclear whether sporoderm-broken spores of G. lucidum water extract (BSGLWE), which contains mainly GLPs, has anticancer effects on colorectal cancer. The present study investigated the anticancer effects and potential mechanisms of BSGLWE on colorectal cancer in vivo and in vitro. Our results showed that BSGLWE significantly inhibited colorectal cancer HCT116 cell viability in a time- and dose-dependent manner. Flow cytometry analysis indicated that BSGLWE disrupted cell cycle progression at G2/M phase via downregulation of cyclin B1 and cyclin A2, and upregulation of P21 at mRNA levels. Moreover, BSGLWE induced apoptosis by decreasing Bcl-2 and survivin at mRNA levels, and reduced Bcl-2, PARP, pro-caspase-3 and pro-caspase-9 at protein levels. Furthermore, BSGLWE suppressed tumor growth in vivo by regulating the expression of genes and proteins associated with cell cycle and apoptosis, which was further confirmed by a reduction of Ki67, PCNA, and Bcl-2 expression as determined by immunohistochemistry staining. NSAID activated gene-1 (NAG-1), a pro-apoptotic gene, was significantly upregulated in vivo and in vitro upon BSGLWE treatment at both mRNA and protein levels. In addition, the relative amounts of secreted NAG-1 in cell culture medium or serum of nude mice were all upregulated upon BSGLWE treatments, suggesting a role of NAG-1 in BSGLWE-induced anticolorectal cancer activity. This is the first study to show that BSGLWE inhibits colorectal cancer carcinogenesis through regulating genes responsible for cell proliferation, cell cycle and apoptosis cascades. These findings indicate that BSGLWE possesses chemopreventive potential in colorectal cancer which may serve as a promising anticancer agent for clinical applications.

Effects of Exogenous Growth Hormone on Growth Hormone-Insulin-Like Growth Factor Axis of Human Gastric Cancer Cell

Aim: To study effects of recombinant human growth hormone (rhGH) on growth hormone-insulin-like growth factor axis (GH-IGFs) of human gastric cancer cell in vivo in order to reveal part mechanism of growth effects of rhGH on gastric cancer. Methods: Nude mice were randomly divided into control group, cisplatin (DDP) group, rhGH group and DDP + rhGH group after human gastric cancer xenograft model of node mice was successfully founded and drugs were used for 6 days. We investigated volume of tumor, inhibitory rate of tumor and cell cycle by slide gauge and flow cytometry. In addition, We also respectively investigated insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) of blood serum of nude mice, IGF-ImRNA, insulin-like growth factor-I receptor (IGF-IR) mRNA and IGFBP-3 mRNA of xenograft of nude mice by enzyme linked immunosorbent assay (ELISA) and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) on the first day of completing use of drugs later. Results: Tumor grew obviously slowly and tumor inhibitory rate obviously rose in DDP group and DDP + rhGH group compared with control group and rhGH group (p p p < 0.05). Expressions of IGF-I mRNA and IGF-IR mRNA were not obviously different in all groups. But expression of IGFBP-3 mRNA obviously increased in rhGH group, DDP group and DDP + rhGH group compared with control group; meanwhile, expression of IGFBP-3 mRNA also obviously increased in DDP + rhGH group compared with control group, DDP group and rhGH group. Conclusion: Our results indicated rhGH in short-time use did not improve proliferation of human gastric cancer cells and its mechanism was possible that rhGH in short-time use raised simultaneously IGF-I and IGFBP-3 of blood serum and increased IGFBP-3 mRNA, but degraded ratio of IGF-I and IGFBP-3 of blood serum in human gastric cancer cells.

Proteomics research about effect of zinc finger protein 139 knockdown with RNA interference on serum of orthotopic transplantation nude mouse with gastric cancer

Objective To observe the effect of inhibiting zinc finger protein 139 (ZNF139) on serum proteins in orthotopic transplantation nude mice model with gastric cancer,and to investigate the mechanism for ZNF139 involved in progression of gastric cancer.Methods Small interfering RNA (siRNA) recombinant plasmid targeting ZNF139 gene was constructed and imported into gastric cancer cell line SGC7901.After screened stably transfected cells by G418,gastric cancer cells were injected into nude mice subcutaneously.Transplanted tumor tissue was constructed through repeatedly subcutaneously inoculating and passaging between nude mice,and 6th-generation subcutaneous tumor was pasted with OB biological glue orthotopically on the stomach wall of BALB/c nude mice.The proteins in nude mice serum samples were separated by fluorescence two-dimensional difference gel electrophoresis (2D-DIGE) and the differential proteins were identified by liquid chromatography-mass spectrometry (LC-MS).Parts of the proteins were identified by Western blotting.Results The tumor-forming rate in orthopotic implantation was 100％ (15/15).ZNF139 was inhibited obviously,and the tumor growth of orthotopic transplantation nude mice model was obviously slower in siRNA-ZNF139 group.Five differential proteins were identified in orthotopic transplantation nude mice serum samples.Results showed that apolipoprotein E (APOE) and the kininogen 1 (KNG1) were down-regulated in gastric cancer orthotopic mouse serum,and mTERF was upregulated after siRNA-ZNF139 interference.Results of Western blotting were consistent with proteomics.Conclusion ZNF139 in gastric cancer may up-regulate serum levels of APOE and KNG1,while down-regulate mTERF to participate in the progression of gastric cancer. Key words: Orthotopic transplantation of gastric cancer; Zinc finger protein 139; Proteomics

Monitoring the progression of metastatic breast cancer on nanoporous silica chips

Breast cancer accounted for 15 per cent of total cancer deaths in female patients in 2010. Although significant progress has been made in treating early-stage breast cancer patients, there is still no effective therapy targeting late-stage metastatic breast cancers except for the conventional chemotherapy interventions. Until effective therapy for later-stage cancers emerges, the identification of biomarkers for the early detection of tumour metastasis continues to hold the key to successful management of breast cancer therapy. Our study concentrated on the low molecular weight (LMW) region of the serum protein and the information it contains for identifying biomarkers that could reflect the ongoing physiological state of all tissues. Owing to technical difficulties in harvesting LMW species, studying these proteins/peptides has been challenging until now. In our study, we have recently developed nanoporous chip-based technologies to separate small proteins/peptides from the large proteins in serum. We used nanoporous silica chips, with a highly periodic nanostructure and uniform pore size distribution, to isolate LMW proteins and peptides from the serum of nude mice with MDA-MB-231 human breast cancer lung metastasis. By matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and biostatistical analysis, we were able to identify protein signatures unique to different stages of cancer development. The approach and results reported in this study possess a significant potential for the discovery of proteomic biomarkers that may significantly enhance personalized medicine targeted at metastatic breast cancer.

金颗粒为活性基底的裸鼠血清表面增强拉曼散射光谱分析

金颗粒为活性基底的裸鼠血清表面增强拉曼散射光谱分析

Establishment of an alpha-fetoprotein-producing human gastric carcinoma in nude mice.

An alpha-fetoprotein (AFP)-producing human gastric carcinoma was transplanted into BALB/c-nu/nu nude mice. The original tumor tissue had been obtained by gastrectomy from a 72-year-old patient with gastric carcinoma. The tumor had been transplanted serially (20 passages) in nude mice. The transplantability was 100%. The doubling time of the tumor ranged from 5.6 days to 11.2 days. AFP appeared in the serum of nude mice 3 to 4 weeks after subcutaneous (sc) transplantation and 6 weeks after intraperitoneal (ip) transplantation of the tumor cell suspension prepared from sc transplanted tumors. A positive correlation was observed between serum AFP level and tumor size. Serum AFP level of mice given ip transplantation increased as a function of time after transplantation. AFP was stained positively by an immunochemical technique in the original and transplanted tumors and was located in the cytoplasms of the tumor cells. The histology of the original tumor was retained. The malignant potential of these transplanted tumor cells was expressed as carcinomatous peritonitis and liver and/or lung metastases.

The Epidermis as a Bioreactor: Topically Regulated Cutaneous Delivery into the Circulation

Previous studies have documented that the skin can be used as a bioreactor to produce proteins for systemic release to treat diseases. A gene-switch system has been developed that allows regulated expression of therapeutic genes. To determine whether this system could be used in the skin, we developed a transgenic mouse model in which expression of a therapeutic gene could be topically induced in epidermal keratinocytes. After a single induction, high levels of the therapeutic protein, human growth hormone (hGH), were released from keratinocytes into the circulation. The serum levels of hGH were dependent on the amount of inducer applied, and repeated induction resulted in increased weight gain by transgenic versus control mice. Furthermore, physiological levels of hGH were detected in the serum of nude mice after topical induction of small transgenic skin grafts. These results clearly demonstrate the feasibility of using the gene-switch system to regulate the delivery of therapeutic proteins into the circulation via genetically modified keratinocytes.

Stability of cytotoxic luteinizing hormone-releasing hormone conjugate (AN-152) containing doxorubicin 14-O-hemiglutarate in mouse and human serum in vitro: implications for the design of preclinical studies.

Recently, we developed a series of cytotoxic peptide conjugates containing 14-O-glutaryl esters of doxorubicin (DOX) or 2-pyrrolino-DOX (AN-201). Serum carboxylesterase enzymes (CE) can partially hydrolyze these conjugates in the circulation, releasing the cytotoxic radical, before the targeting is complete. CE activity in serum of nude mice is about 10 times higher than in human serum. Thus, we found that the t(1/2) of AN-152, an analog of luteinizing hormone-releasing hormone (LH-RH) containing DOX, at 0.3 mg/ml is 19. 49 +/- 0.74 min in mouse serum and 126.06 +/- 3.03 min in human serum in vitro. The addition of a CE inhibitor, diisopropyl fluorophosphate (DFP), to mouse serum in vitro significantly (P < 0. 01) prolongs the t(1/2) of AN-152 to 69.63 +/- 4.44 min. When DFP is used in vivo, 400 nmol/kg cytotoxic somatostatin analog AN-238 containing AN-201 is well tolerated by mice, whereas all animals die after the same dose without DFP. In contrast, DFP has no effect on the tolerance of AN-201. A better tolerance to AN-238 after DFP treatment is due to the selective uptake of AN-238 by somatostatin receptor-positive tissues. Our results demonstrate that the suppression of the CE activity in nude mice greatly decreases the toxicity of cytotoxic hybrids containing 2-pyrrolino-DOX 14-O-hemiglutarate and brings this animal model closer to the conditions that exist in humans. The use of DFP together with these peptide conjugates in nude mice permits a better understanding of their mechanism of action and improves the clinical predictability of the oncological and toxicological results.

Basic studies on IL-2 gene therapy for head and neck carcinoma

Basic studies on transduction of the interleukin-2 (IL-2) gene into tumor cells were carried out in order to develop a new immunotherapy for head and neck carcinomas. We transduced the IL-2 gene into KB cells using defective herpes simplex viral (HSV) amplicon vector as the gene transfer vehicle. A high level of IL-2 was produced by IL-2 gene transduced KB cells (KB/IL-2). Human peripheral blood mononuclear cells (PBMC) cultured in medium containing the culture supernatant of KB/IL-2 cells showed stronger cytotoxic activity against KB cells than the control. In in vivo studies, high levels of IL-2 and interferon-gamma (IFN-gamma) were detected in the serum of nude mice transplanted with KB/IL-2 cells. The spleen cells of KB/IL-2 cell-transplanted nude mice exhibited high cytotoxic activity. Three of 5 nude mice transplanted with KB/IL-2 cells were completely cured of their tumor, and all 3 mice survived for over 120 days. All 5 nude mice transplanted with KB/lacZ cells, and all 5 nude mice transplanted with KB cells died within 120 days as a result of tumor progression. In conclusion, transduction of IL-2 gene tumor cells was corroborated by the high level of IL-2 produced by KB/IL-2 cells. The mechanisms of tumor rejection on KB/IL-2 transplanted nude mice were thought to be that effector cells stimulated by IL-2 derived from transplanted KB/IL-2 cells killed tumor cells, and IFN-gamma produced by activated NK cells showed a synergistic effect on tumor cells-killing.

Column-Switching High-Performance Liquid Chromatographic Assay for Minocycline of Nude Mice Serum

A rapid, direct, accurate and sensitive liquid chromatographic assay with on-line extraction for minocycline of nude mice serum is described. Serum was directly injected onto the extraction column where the drug was separated from the serum concomitants using a solid phase extraction procedure based on cation exchange. Using an on-line column switching system, minocycline was quantitatively transferred and separated on the analytical column. Ultraviolet absorption at 352 nm was used for detection. The assay was linear from 0.2 to 10 μg/mL with a correlation coefficient of 0.999. Detection limit was 50 ng/mL. Recovery was 97%. The method has been developed for the determination of minocycline levels of nude mice serum collected from a study designed to evaluate the potential for tumor anti-angiogenic effects of this drug.