Plasma Metabolomic Changes in Mice With Time-restricted Feeding-attenuated Spontaneous Metastasis of Lewis Lung Carcinoma.

BACKGROUND/AIM: Time-restricted feeding (TRF) during the dark phase of the day restores metabolic homeostasis in mice. MATERIALS AND METHODS: We performed untargeted metabolomic analysis on plasma from mice subjected to TRF that attenuates high-fat diet-enhanced spontaneous metastasis of Lewis lung carcinoma (LLC). RESULTS: Twenty-four of 152 identified metabolites differed among the four dietary groups (non-LLC-bearing mice fed the AIN93G diet and LLC-bearing mice fed the AIN93G, the high-fat diet (HFD), or TRF of the HFD). Component 1 of sparse partial least squares-discriminant analysis showed a clear separation between non-LLC-bearing and LLC-bearing mice. Major metabolites responsible for the changes were elevations in α-tocopherol, docosahexaenoic acid, cholesterol, dihydrocholestrol, isoleucine, leucine, and phenylalanine and decreases in lactic acid and pyruvic acid in LLC-bearing mice particularly those fed the HFD. Time-restricted feeding shifted the metabolic profile of LLC-bearing mice towards that of non-LLC-bearing controls. CONCLUSION: Time-restricted feeding improves metabolic profile of LLC-bearing mice.

Time-restricted Feeding Attenuates High-fat Diet-enhanced Spontaneous Metastasis of Lewis Lung Carcinoma in Mice.

BACKGROUND/AIM: Obesity is a risk factor for cancer. Disruption of the daily feeding and fasting rhythm can contribute to obesity. This study tested the hypothesis that time-restricted feeding (TRF) attenuates obesity-enhanced metastasis. MATERIALS AND METHODS: In a spontaneous metastasis model of Lewis lung carcinoma (LLC), male C57BL/6 mice were fed the standard AIN93G diet or a high-fat diet (HFD) with or without dark-phase restricted feeding (12 h per day) for 10 weeks. Pulmonary metastases from a subcutaneous tumor were quantified. RESULTS: The number and size of lung metastases were greater in the HFD group than in the AIN93G group, but did not differ between the TRF and AIN93G groups. TRF prevented HFD-induced increases in plasma concentrations of glucose, insulin, proinflammatory cytokines (leptin, monocyte chemotactic protein-1, plasminogen activator inhibitor-1), and angiogenic factors (angiopoietin-2, hepatic growth factor, vascular endothelial growth factor). CONCLUSION: TRF attenuates the HFD-enhanced spontaneous metastasis of LLC in mice.

Monocyte chemotactic protein-1 deficiency attenuates and high-fat diet exacerbates bone loss in mice with Lewis lung carcinoma.

Bone loss occurs in obesity and cancer-associated complications including wasting. This study determined whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects in male C57BL/6 mice with Lewis lung carcinoma (LLC) metastases in lungs. Compared to non-tumor-bearing mice, LLC reduced bone volume fraction, connectivity density, trabecular number, trabecular thickness and bone mineral density and increased trabecular separation in femurs. Similar changes occurred in vertebrae. The high-fat diet compared to the AIN93G diet exacerbated LLC-induced detrimental structural changes; the exacerbation was greater in femurs than in vertebrae. Mice deficient in MCP-1 compared to wild-type mice exhibited increases in bone volume fraction, connectivity density, trabecular number and decreases in trabecular separation in both femurs and vertebrae, and increases in trabecular thickness and bone mineral density and a decrease in structure model index in vertebrae. Lewis lung carcinoma significantly decreased osteocalcin but increased tartrate-resistant acid phosphatase 5b (TRAP 5b) in plasma. In LLC-bearing mice, the high-fat diet increased and MCP-1 deficiency decreased plasma TRAP 5b; neither the high-fat diet nor MCP-1 deficiency resulted in significant changes in plasma concentration of osteocalcin. In conclusion, pulmonary metastasis of LLC is accompanied by detrimental bone structural changes; MCP-1 deficiency attenuates and high-fat diet exacerbates the metastasis-associated bone wasting.

Alteration of the exDNA profile in blood serum of LLC-bearing mice under the decrease of tumour invasion potential by bovine pancreatic DNase I treatment.

Taking into account recently obtained data indicating the participation of circulating extracellular DNA (exDNA) in tumorigenesis, enzymes with deoxyribonucleic activity have again been considered as potential antitumour and antimetastatic drugs. Previously, using murine Lewis lung carcinoma and hepatocellular carcinoma A1 tumour models, we have shown the antimetastatic activity of bovine DNase I, which correlates with an increase of DNase activity and a decrease of exDNA concentration in the blood serum of tumour-bearing mice. In this work, using next-generation sequencing on the ABS SOLiD™ 5.500 platform, we performed a search for molecular targets of DNase I by comparing the exDNA profiles of healthy animals, untreated animals with Lewis lung carcinoma (LLC) and those with LLC treated with DNase I. We found that upon DNase I treatment of LLC-bearing mice, together with inhibition of metastasis, a number of strong alterations in the patterns of exDNA were observed. The major differences in exDNA profiles between groups were: i) the level of GC-poor sequences increased during tumour development was reduced to that of healthy mice; ii) levels of sequences corresponding to tumour-associated genes Hmga2, Myc and Jun were reduced in the DNase I-treated group in comparison with non-treated mice; iii) 224 types of tandem repeat over-presented in untreated LLC-bearing mice were significantly reduced after DNase I treatment. The most important result obtained in the work is that DNase I decreased the level of B-subfamily repeats having homology to human ALU repeats, known as markers of carcinogenesis, to the level of healthy animals. Thus, the obtained data lead us to suppose that circulating exDNA plays a role in tumour dissemination, and alteration of multiple molecular targets in the bloodstream by DNase I reduces the invasive potential of tumours.

Hydrophilic mesoporous carbon nanospheres with high drug-loading efficiency for doxorubicin delivery and cancer therapy.

In this study, a highly effective transmembrane delivery vehicle based on PEGylated oxidized mesoporous carbon nanosphere (oMCN@PEG) was successfully fabricated in a facile strategy. oMCN@PEG exhibited a narrow size distribution of 90 nm, excellent hydrophilicity, good biocompatibility, and a very high loading efficiency for doxorubicin (DOX). The drug system (oMCN@DOX@PEG) exhibited excellent stability under neutral pH conditions, but with dramatic releases of DOX at reduced pH conditions. Pharmacokinetics study revealed that oMCN@DOX@PEG could prolong the circulation of DOX in the blood stream. The endocytosis, cytotoxicity, and anticancer effect in vitro and in vivo of the drug-loaded nanoparticles were also evaluated. Our results showed that the nanoparticles efficiently penetrated the membrane of tumor cells, subsequently released drugs, and efficiently inhibited the growth of cancer cells both in vitro and in vivo. Especially, oMCN@DOX@PEG also exhibited significant antimetastasis effect in advanced stage of malignant cancer, improving the survival time of tumor-bearing mice. The results suggested that oMCN@PEG might be a promising anticancer drug delivery vehicle for cancer therapy.

Metabolic response of LLC xenografted mice to oxythiamine, as measured by [¹H] NMR spectroscopy.

Oxythiamine (OT) has been proven to be a potential anticancer drug. With the help of NMR-based metabonomics, we studied the metabolic changes within tumor-bearing mice with different levels of OT administration using a C57BL/6 mouse Lewis lung carcinoma tumor transplantation model. We administered different concentrations of OT (75, 150, 300, and 600 mg∙kg(-1)∙day(-1)) to the mice orally for 2 weeks, recorded animal weights and tumor volumes, sacrificed the animals, and collected blood and tumor mass samples for nuclear magnetic resonance determination. Compared with the findings for the control (untreated) group, the tumor weights and volumes of the 150, 300, and 600 mg∙kg-1∙day-1 groups decreased with no difference among these OT groups. A large metabolite difference was observed in plasma metabolites between the blank and control groups, which indicated the success of the tumor-bearing model. The metabolites in tumor associated with thiamine-dependent enzymes (TDEs) underwent considerable change between the OT and control groups, exhibiting concentration dependence and enzyme specificity. The restriction of TDEs by OT may be a major mechanism underlying its anticancer effect. The role of OT as a potential anticancer drug and a dehydrogenase inhibitor should therefore be taken into consideration in future tumor research.

Antitumor and immunomodulatory activity of polysaccharide isolated from Trametes orientalis.

A water-soluble polysaccharide (TOP-2) was isolated from Trametes orientalis, consisting of galactose, glucose, mannose, and arabinose with the molar ratios of 5.79:5.77:3.45:1, having an average molecular weight of 63kDa. The antitumor and immunomodulatory activity of TOP-2 were determined in Lewis lung carcinoma (LLC) tumor-bearing mice. The results revealed that TOP-2 not only could efficaciously restrain the growth of LLC in mice, but also effectively increase the body weight and relative spleen/thymus weight. In addition, TOP-2 remarkably enhanced splenocyte proliferation, notably stimulated phagocytotic function of macrophages, and strikingly promoted the expression of serum cytokines. These findings indicate that TOP-2 exert antitumor activity in vivo potentially by improving immune function. TOP-2 could be empoldered as a potential supplementary agent for cancer treatment.

[Astragalus polysaccharides combined with cisplatin decreases the serum levels of CD44 and collagen type IV and hyaluronic acid in mice bearing Lewis lung cancer].

OBJECTIVE: To observe the effects of Astragalus polysaccharides (APS) combined with cisplatin on growth of Lewis lung cancer (LLC), serum content of collagen type IV (Col4) and hyaluronic acid (HA), and CD44 protein level in LLC-bearing mice. METHODS: C57BL/6J mice (n=90) were randomly divided into 2 groups, 10 mice for blank control group, and 80 mice for tumor-bearing group. The tumor-bearing group was then randomized into 8 subgroups, 10 mice for each subgroup. The tumor-bearing mice were treated by peritoneal injection of normal saline, 6 mg/kg cisplatin, 50, 100, 200 mg/kg APS, and 3 mg/kg cisplatin combined with 50, 100, 200 mg/kg APS, respectively. APS (0.3 mL) was injected once a day from the first to the 20th day after LLC transplantation, and cisplatin of the same volume was injected once a week. On the 21st day, the blood was taken from the eyeballs of all experimental mice. Col4 and HA contents in serum were detected by radioimmunoassay. The expression of CD44 in transplanted tumor cells was determined by immunohistochemistry and image analysis. The inhibition rate of tumor growth was also counted. RESULTS: The inhibition rates of 6 mg/kg cisplatin, 50, 100, 200 mg/kg APS, and 3 mg/kg cisplatin combined with 50, 100, 200 mg/kg APS on LLC growth in the mice were 49.30%, 17.21%, 39.68%, 42.98%, 51.02%, 57.21% and 65.11%, respectively. Compared with the control subgroup of the tumor-bearing group, cisplatin, APS and cisplatin combined with APS reduced significantly the Col4 and HA content in serum, and down-regulated the expression of CD44. CONCLUSION: APS can inhibit the growth of LLC cells, reduce the Col4 and HA content in serum, down-regulate the expression of CD44 protein in LLC-bearing mice, and enhance the therapeutic effect when combined with cisplatin, indicating that it can decrease the toxicity of cisplatin against tumor.

Social defeat stress promotes tumor growth and angiogenesis by upregulating vascular endothelial growth factor/extracellular signal-regulated kinase/matrix metalloproteinase signaling in a mouse model of lung carcinoma.

Numerous epidemiological and experimental animal studies have indicated that chronic psychological stress may promote tumor development. However, the underlying molecular mechanisms by which chronic stress promotes tumorigenesis remain to be fully elucidated and animal models have not yet been well established. In the present study, an established mouse model of repeated social defeat stress (RSDS), was generated and used to investigate the effect of stress on tumor growth and metastasis. C57BL/6 mice were exposed to RSDS for 10 days, followed by subcutaneousl inoculation with Lewis lung carcinoma cells for seven days. The tumor weight and volume as well as the number of the lung metastatic nodules were then determined. Vascular endothelial growth factor (VEGF) serum levels were measured using ELISAs. In addition, expression levels of VEGF receptor (VEGFR) and L1 cell adhesion molecule (L1CAM) messenger (m)RNA were confirmed using reverse transcription quantitative polymerase chain reaction. Furthermore, protein expression levels of phosphorlyated extracellular signal-regulated kinase (pERK), matrix metalloproteinase (MMP)-2 and MMP-9 were examined using western blot analysis. The results showed that RSDS significantly increased the weight and the volume of the primary tumor as well as the number of the lung metastatic nodules. Serum VEGF levels were significantly higher in the tumor-stress group compared with those of the unstressed tumor mice. In addition, tumors in stressed animals demonstrated markedly enhanced expression of VEGFR-2 and L1CAM mRNA as well as pERK, MMP-2 and MMP-9 protein expression. In conclusion, these results suggested that RSDS contributed to lung cancer progression, angiogenesis and metastasis, which was partially associated with increased VEGF secretion and therefore the activation of the ERK signaling pathway, resulting in the induction of MMP-2 and MMP-9 protein expression.

Effects of a high-fat diet on spontaneous metastasis of Lewis lung carcinoma in plasminogen activator inhibitor-1 deficient and wild-type mice.

This study investigated the effects of a high-fat diet on spontaneous metastasis of Lewis lung carcinoma (LLC) in plasminogen activator inhibitor-1 deficient (PAI-1-/-) and wild-type mice. The high-fat diet increased the number of pulmonary metastases by 60% (p<0.01), tumor cross-sectional area by 82% (p<0.05) and tumor volume by 130% (p<0.05) compared to the AIN93G diet. Deficiency in PAI-1 reduced the number of metastases by 35% (p<0.01) compared to wild-type mice. In mice fed the high-fat diet, PAI-1 deficiency reduced tumor cross-sectional area by 52% (p<0.05) and tumor volume by 61% (p<0.05) compared to their wild-type counterparts; however, PAI-1 deficiency affected neither area nor volume in mice fed the AIN93G diet. Adipose and plasma concentrations of PAI-1 were significantly higher in high-fat fed wild-type mice than in their AIN93G-fed counterparts. Adipose and plasma PAI-1 were not detectable in PAI-1-/- mice regardless of the diet. Mice deficient in PAI-1 showed significantly greater plasma concentrations of monocyte chemotactic protein-1, tumor necrosis factor-α, leptin, vascular endothelial growth factor, tissue inhibitor of metalloproteinase-1 and insulin compared to wild-type mice, indicating a compensatory overproduction of inflammatory cytokines, angiogenic factors and insulin in the absence of PAI-1. We conclude that PAI-1 produced by the host, including that by adipose tissue, promotes high-fat enhanced metastasis of LLC.

Antitumor activities of ginseng polysaccharide in C57BL/6 mice with Lewis lung carcinoma.

In the present study, we prepared ginseng polysaccharide (GP) and evaluated its antitumor and immunomodulatory activities in C57BL/6 mice bearing with Lewis lung carcinoma (LLC). Administration of GP (50, 100, and 200 mg/kg) could not only significantly inhibit the growth of transplantable LLC tumor in C57BL/6 mice but also remarkably increase relative weight of spleen and thymus, splenocytes proliferation, and the ratio of CD4(+)/CD8(+) T lymphocyte in peripheral blood in LLC-bearing mice. Furthermore, the serum IL-2 and IFN-γ production and NK cytolytic activity were also prompted in LLC-bearing mice in response to GP treatment at three doses. Additionally, GP showed no side effects such as weight loss in body weight and internal organs (lung, liver, kidney, and heart) as well as inactivity during the experiment. Therefore, GP might be conveniently exploited to be good immune-stimulating modifiers and had the potential value for tumor therapy.

Tocilizumab, a proposed therapy for the cachexia of Interleukin6-expressing lung cancer.

BACKGROUND: We previously reported the role of IL-6 in a murine model of cancer cachexia and currently documented a patient in whom tocilizumab, anti-IL-6 receptor antibody, dramatically improved cachexia induced by IL-6 over-expressing lung cancer. Despite this potential to alleviate cancer cachexia, tocilizumab has not been approved for this clinical use. Therefore, preceding our planned clinical trial of tocilizumab, we designed the two studies described here to evaluate the levels of IL-6 in patients with lung cancer and the effect of tocilizumab in a murine model of human cancer cachexia. METHODS: First, we measured serum IL-6 levels in patients with lung cancer and analyzed its association with cachexia and survival. Next, we examined the effect of a rodent analog of tocilizumab (MR16-1) in the experimental cachexia model. RESULTS: Serum IL-6 levels were higher in patients with cachexia than those without cachexia. In patients with chemotherapy-resistant lung cancer, a high IL-6 serum level correlated strongly with survival, and the cut-off level for affecting their prognosis was 21 pg/mL. Meanwhile, transplantation of IL-6-expressing Lewis Lung Carcinoma cells caused cachexia in mice, which then received either MR16-1 or 0.9% saline. Tumor growth was similar in both groups; however, the MR16-1 group lost less weight, maintained better food and water intake and had milder cachectic features in blood. MR16-1 also prolonged the survival of LLC-IL6 transplanted mice (36.6 vs. 28.5 days, p = 0.016). CONCLUSION: Our clinical and experimental studies revealed that serum IL-6 is a surrogate marker for evaluating cachexia and the prognosis of patients with chemotherapy resistant metastatic lung cancer and that tocilizumab has the potential of improving prognosis and ameliorating the cachexia that so devastates their quality of life. This outcome greatly encourages our clinical trials to evaluate the safety and efficacy of tocilizumab treatment for patients with increased serum IL-6.

Tumor endothelial markers define novel subsets of cancer-specific circulating endothelial cells associated with antitumor efficacy.

Circulating endothelial cells (CEC) are derived from multiple sources, including bone marrow (circulating endothelial progenitors; CEP), and established vasculature (mature CEC). Although CECs have shown promise as a biomarker for patients with cancer, their utility has been limited, in part, by the lack of specificity for tumor vasculature and the different nonmalignant causes that can impact CEC. Tumor endothelial markers (TEM) are antigens enriched in tumor versus nonmalignant endothelia. We hypothesized that TEMs may be detectable on CEC and that these circulating TEM(+) endothelial cells (CTEC) may be a more specific marker for cancer and tumor response than standard CEC. We found that tumor-bearing mice had a relative increase in numbers of circulating CTEC, specifically with increased levels of TEM7 and TEM8 expression. Following treatment with various vascular-targeting agents, we observed a decrease in CTEC that correlated with the reductions in tumor growth. We extended these findings to human clinical samples and observed that CTECs were present in patients with esophageal cancer and non-small cell lung cancer (N = 40), and their levels decreased after surgical resection. These results demonstrate that CTECs are detectable in preclinical cancer models and patients with cancer. Furthermore, they suggest that CTECs offer a novel cancer-associated marker that may be useful as a blood-based surrogate for assessing the presence of tumor vasculature and antiangiogenic drug activity.

Umbelliprenin induced production of IFN-γ and TNF-α, and reduced IL-10, IL-4, Foxp3 and TGF-ß in a mouse model of lung cancer.

Umbelliprenin is a member of the 7-prenyloxycoumarins with potential therapeutic properties such as cytotoxic effects on various cancer cells. The present study investigates the effect of umbelliprenin on predominance of Th1 and Th2 responses in Lewis lung cancer (LLC) mouse model. The cytotoxic effect of umbelliprenin was explored on LLC cells and mouse splenocytes by MTT assay. Mice into which LLC had been transplanted were treated with umbelliprenin on alternate days, at 2.5 mg/200 µl intraperitoneally. Foxp3, TNF-α and TGF-ß mRNA expressions were assessed in tumor and lung tissues of LLC mice. In addition, IL-10, IFN-γ and IL-4 levels were determined in sera and also in splenocyte culture supernatants at the presence of tumor cell lysate (10 µg/ml) and Con A (3 µg/ml) after 72 h. Results showed the cytotoxic effects of umbelliprenin on LLC cells (IC50 = 51.6 ± 5.4 µM) while no adverse effect was seen at this concentration on normal splenocytes. TNF-α mRNA expression in both lung and tumor tissues was increased. However, Foxp3 and TGF-ß expressions were decreased in tumor tissues. Serum level of IFN-γ was elevated in the umbelliprenin treated cancerous mice compared to the control group while IL-10 and IL-4 secretions were reduced. Tumor size was also decreased in umbelliprenin treated group. In summary, umbelliprenin has shown a partially Th1 bias with a reduction of regulatory immune response. Although the mechanism behind this action is not known, it is speculated that upon changing the Th1/Th2 balance in favour of Th1, umbelliprenin induces its antitumor activity.

Curcumin reduces trabecular and cortical bone in naive and lewis lung carcinoma-bearing mice.

The present study investigated the effects of curcumin on bone microstructure in non-tumor-bearing and Lewis lung carcinoma-(LLC)-bearing female C57BL/6 mice. Morphometric analysis showed that dietary supplementation with curcumin (2% or 4%) significantly reduced the bone volume to total volume ratio, connectivity density and trabecular number, and significantly increased the structure model index (an indicator of the plate- and rod-like geometry of trabecular structure) and trabecular separation in vertebral bodies compared to controls in both non-tumor-bearing and LLC-bearing mice. Similar changes in trabecular bone were observed in the femoral bone in curcumin-fed mice. Curcumin significantly reduced the cortical bone area to total area ratio and cortical thickness in femoral mid-shaft, but not in vertebral bodies, in both non-tumor-bearing and LLC-bearing mice. Curcumin feeding reduced plasma concentrations of osteocalcin and increased tartrate-resistant acid phosphate 5b in mice regardless of the presence of LLC, indicating that curcumin disrupts the balance of bone remodeling. Our results demonstrated that curcumin reduced the trabecular bone volume and cortical bone density. The skeleton is a favored site of metastasis for many types of cancers, and curcumin has been investigated in clinical trials in patients with cancer for its chemopreventive effects. Our results suggest the possibility of a combined effect of cancer-induced osteolysis and curcumin-stimulated bone loss in patients using curcumin. The assessment of bone structural changes should be considered for those who participate in curcumin clinical trials to determine its effects on skeleton health, particularly for those with advanced malignancies.

[Organ-specific antitoxic effects of N-stearoylethanolamine in male mice with Lewis carcinoma under doxorubicin intoxication].

With the introduction of doxorubicin into mice with Lewis carcinoma in the heart and liver tissues and kidney the organ-antitoxic effects of N-stearoilethanolamine (NSE) were found, which depended on its concentration. Administration of doxorubicin to male mice leads to an increase in the level of urea and creatinine, as well as activation of ALT in blood plasma. Introduction of NSE resulted in normalization of these parameters to the level of intact animals. In the heart tissue doxorubicin has multidirectional effects on the activity of antioxidant enzymes, in particular it decreases the activity of catalase and superoxide dismutase activity increases. Introduction of NSE normalizes these two indicators. It was found that tumor growth leads to an increase in the activity of glutathione peroxidase and superoxide dismutase. Introduction of NSE normalizes activity of these enzymes. Doxorubicin causes an increase in catalase activity in the kidney of mice with tumour, NSE prevented the increase in the activity of the above enzyme. The cancer process leads to increased levels of catalase activity in the liver of tumour-bearing mice, the introduction of NSE decreases the enzyme activity.

A study of 131iodine-labeling of histamine-indomethacin: its in vivo therapeutic effect and anti-tumor mechanisms in Lewis-bearing lung cancer.

BACKGROUND: In our research,we study the effect of 131iodine-labeled histamine-indomethacin (131I-His-IN). We focus on its in vivo therapeutic effect and anti-tumor mechanisms in Lewis-bearing lung cancer. METHODS: 131I-His-IN was administered by garage to the mice. At different timepoints, we made autoradiography (ARG) slices to observe the distribution of 131I-His-IN in the cellular, and the sliced samples underwent hematoxylin and eosin (HE) staining for observation of tumor necrosis. Before treatment, the groups of mice underwent 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) scans ,and they were then given physiologic saline, iodine 131 (131I), indomethacin (IN), Histamine-indomethacin (His-IN), and 131I-His-IN, respectively, three times daily for seven days. Seven days later, all the mice underwent 18F-FDG PET-CT scans again. We calculated the maximum standard uptake value (SUVmax) of the region of interest (ROI) and tumor inhibition rate at the same time. RESULTS: In ARG groups, black silver particle was concentrated in the nucleus and cytoplasm. 131I-His-IN mainly concentrated in tumor tissues. At 8 hours after 131I-His-IN, the radioactivity uptake in tumor tissue was higher than in other organs (F=3.46, P<0.05). For the 18F-FDG PET-CT imaging, the tumor tissuses SUVmax of the ROI was lower compared to other groups after the treatment with 131I-His-IN. The tumor inhibitory rate (54.8%) in 131I-His-IN group was higher than in other groups, too. In the 131I-His-IN group the vascular endothelial growth factor (VEGF) decreased gradually compared to other groups. The tumor tissue necrotized obviously in 131I-His-IN group. CONCLUSIONS: Through these animal experiments, we found 131I-His-IN could inhibit the Lewis lung cancer cells. 131I-His-IN focused at the cell nucleus and cytoplasm. It could reduce VEGF and increase tumor inhibitory rate. At the same time, 18F-FDG PET-CT scan could be used for a curative effect and monitoring of disease prognosis.

The effects of exercise training on levels of vascular endothelial growth factor in tumor-bearing mice.

BACKGROUND: Vascular endothelial growth factor (VEGF) affects tumor growth and metastasis by mediating angiogenesis. Vascular endothelial growth factor overexpression is considered a predictor of poor prognosis in cancer patients. Exercise may increase the circulating levels of VEGF, which is important to angiogenesis. We examined the effects of exercise training on VEGF levels and tumor growth in male C57BL/6 mice inoculated with Lewis lung cancer cells. METHODS: Thirty-two mice were randomly assigned to either the tumor control (TC, n=16) group or the tumor exercise (TE, n=16) group. Half of the mice in TE group received aerobic interval exercise training, and the other half received aerobic continuous exercise training for 4 weeks. The animal weights and tumor volumes were assessed three times per week. Serum VEGF levels were determined at baseline, 2 and 4 weeks. The solid tumor, lung and liver were excised and evaluated at study completion. RESULTS: There was a significant increase in VEGF levels after the 4-week exercise training program in TE group, but no significant changes were observed in TC group. CONCLUSIONS: Although exercise training increased serum VEGF levels, group differences were not evident in our study. Exercise training did not alter the survival rate or tumor growth in tumor-bearing mice.

Tissue inhibitors of matrix metalloproteinases 1 and 2 and matrix metalloproteinase activity in the serum and lungs of mice with lewis lung carcinoma.

We studied the content of tissue inhibitors of matrix metalloproteinases 1 and 2 (TIMP-1 and TIMP-2) and activities of matrix metalloproteinases (MMP) in the serum and lungs of mice with Lewis lung carcinoma metastasizing into the lung. Metastasizing was associated with increased serum content of TIMP-1 and TIMP-2 (only on day 20 at the terminal stage of the tumor process). These data confirm the hypothesis on pro-tumorigenic role of TIMP-1 in the serum. Locally, the development of metastases was associated with a decrease in TIPM-1 concentration (day 7), an increase in TIMP-2 concentration (days 7 and 20), and elevated activity of MMP at all terms of the study (days 7, 15, and 20). Increased concentration of TIMP-2 in the lungs (but not in the serum) can be regarded as an indicator of Lewis lung carcinoma metastasizing.

Neutrophils promote liver metastasis via Mac-1-mediated interactions with circulating tumor cells.

Although circulating neutrophils are associated with distant metastasis and poor outcome in a number of epithelial malignancies, it remains unclear whether neutrophils play an active causal role in the metastatic cascade. Using in vivo models of metastasis, we found that neutrophils promote cancer cell adhesion within liver sinusoids and, thereby, influence metastasis. Neutrophil depletion before cancer cell inoculation resulted in a decreased number of gross metastases in an intrasplenic model of liver metastasis. This effect was reversed when inflamed neutrophils were co-inoculated with cancer cells. In addition, early adhesion within liver sinusoids was inhibited in the absence of neutrophils and partially restored with a short perfusion of isolated activated neutrophils. Intravital microscopy showed that cancer cells adhered directly on top of arrested neutrophils, indicating that neutrophils may act as a bridge to facilitate interactions between cancer cells and the liver parenchyma. The adhesion of lipopolysaccharide-activated neutrophils to cancer cells was mediated by neutrophil Mac-1/ICAM-1. Our findings, therefore, show a novel role for neutrophils in the early adhesive steps of liver metastasis.