The phase of the cell cycle can determine whether a cancer cell can respond to a given drug. We report here on the results of monitoring of real-time cell cycle dynamics of cancer cells throughout a live tumor intravitally using a fluorescence ubiquitination cell cycle indicator (FUCCI) before, during, and after chemotherapy. In nascent tumors in nude mice, approximately 30% of the cells in the center of the tumor are in G?/G? and 70% in S/G?/M. In contrast, approximately 90% of cancer cells in the center and 80% of total cells of an established tumor are in G?/G? phase. Similarly, approximately 75% of cancer cells far from (> 100 µm) tumor blood vessels of an established tumor are in G?/G?. Longitudinal real-time imaging demonstrated that cytotoxic agents killed only proliferating cancer cells at the surface and, in contrast, had little effect on quiescent cancer cells, which are the vast majority of an established tumor. Moreover, resistant quiescent cancer cells restarted cycling after the cessation of chemotherapy. Our results suggest why most drugs currently in clinical use, which target cancer cells in S/G?/M, are mostly ineffective on solid tumors. The results also suggest that drugs that target quiescent cancer cells are urgently needed.
Skeletal muscle depletion or sarcopenia has been identified as a poor prognostic factor for various diseases. The aim of this study is to determine whether muscle depletion is a prognostic factor for hepatocellular carcinoma (HCC).
The aim of this study is to determine the efficacy of tumor-targeting Salmonella typhimurium A1-R (A1-R) on pancreatic cancer patient-derived orthotopic xenografts (PDOX). The PDOX model was originally established from a pancreatic cancer patient in SCID-NOD mice. The pancreatic cancer PDOX was subsequently transplanted by surgical orthotopic implantation (SOI) in transgenic nude red fluorescent protein (RFP) mice in order that the PDOX stably acquired red fluorescent protein (RFP)-expressing stroma for the purpose of imaging the tumor after passage to non-transgenic nude mice in order to visualize tumor growth and drug efficacy. The nude mice with human pancreatic PDOX were treated with A1-R or standard chemotherapy, including gemcitabine (GEM), which is first-line therapy for pancreatic cancer, for comparison of efficacy. A1-R treatment significantly reduced tumor weight, as well as tumor fluorescence area, compared to untreated control (P?=?0.011), with comparable efficacy of GEM, CDDP, and 5-FU. Histopathological response to treatment was defined according to Evans's criteria and A1-R had increased efficacy compared to standard chemotherapy. The present report is the first to show that A1-R is effective against a very low-passage patient tumor, in this case, pancreatic cancer. The data of the present report suggest A1-1 will have clinical activity in pancreatic cancer, a highly lethal and treatment-resistant disease and may be most effectively used in combination with other agents.
We have previously shown that cancer cells can form an intravascular niche where they can proliferate and undergo apoptosis as well as traffic and extravasate. In the present study, green fluorescent protein (GFP) was expressed in the cytoplasm of HT-1080 human fibrosarcoma cells, and red fluorescent protein (mCherry), linked to histone H2B, was expressed in the nucleus to further investigate intravascular cancer cell nuclear-cytoplasmic dynamics. Nuclear mCherry expression enabled visualization of nuclear dynamics, whereas simultaneous cytoplasmic GFP expression enabled visualization of nuclear-cytoplasmic ratios as well as simultaneous cell and nuclear deformation. Cancer cells were injected in the epigastric cranialis vein in an abdominal flap of nude mice to enable subcellular in vivo imaging. The cell cycle position of individual living cells was readily-visualized by the nuclear-cytoplasmic ratio and nuclear morphology. Real-time induction of apoptosis was observed by nuclear size changes and progressive nuclear fragmentation. Intra- and extra-vascular mitotic cells were visualized by imaging. One hour after cell injection, round and elongated cancer cells were observed in the vessels. Three hours after injection, invadopodia-like structures of the cancer cells were observed. Five hours after injection, dual-color cancer cells began to divide within the vessel. By 10 h, some intravascular cancer cells underwent apoptosis. Deformed new blood vessels in the tumor were observed 10 days later. Extravascular cancer cells were imaged dividing in the tumor at day 14 after injection. The subcellular in vivo imaging approach described in the present report provides new visual targets for trafficking and proliferating intravascular cancer cells as well as extravasating and invading cancer cells.
A 61-year-old female was admitted to our hospital with severe jaundice and anemia. She was diagnosed with severe acute hepatitis secondary to autoimmune hepatitis (AIH) on the basis of positive anti-nuclear antibody titers, high serum IgG levels, and liver biopsy. Autoimmune hemolytic anemia (AIHA) was diagnosed because of the presence of reticulocytosis, decreased haptoglobin, positive direct Coombs test, and erythroid hyperplasia in the bone marrow. Although AIH occurs in association with various immunological disorders, an association with AIHA is rarely reported. We report a rare case of severe AIH associated with AIHA.
The XPA1 human pancreatic cancer cell line is dimorphic, with spindle stem-like cells and round non-stem cells. We report here the in vitro IC 50 values of stem-like and non-stem XPA1 human pancreatic cells cells for: (1) 5-fluorouracil (5-FU), (2) cisplatinum (CDDP), (3) gemcitabine (GEM), and (4) tumor-targeting Salmonella typhimurium A1-R (A1-R). IC 50 values of stem-like XPA1 cells were significantly higher than those of non-stem XPA1 cells for 5-FU (P = 0.007) and CDDP (P = 0.012). In contrast, there was no difference between the efficacy of A1-R on stem-like and non-stem XPA1 cells. In vivo, 5-FU and A1-R significantly reduced the tumor weight of non-stem XPA1 cells (5-FU; P = 0.028; A1-R; P = 0.011). In contrast, only A1-R significantly reduced tumor weight of stem-like XPA1 cells (P = 0.012). The combination A1-R with 5-FU improved the antitumor efficacy compared with 5-FU monotherapy on the stem-like cells (P = 0.004). The results of the present report indicate A1-R is a promising therapy for chemo-resistant pancreatic cancer stem-like cells.
The poor prognosis for patients with hepatocellular carcinoma (HCC) is associated with its high rate of recurrence in the cirrhotic liver. Therefore, more effective strategies need to be urgently developed for the chemoprevention of this malignancy. The malfunction of retinoid X receptor ?, a retinoid receptor, due to phosphorylation by Ras/mitogen-activated protein kinase is closely associated with liver carcinogenesis and may be a promising target for HCC chemoprevention. Acyclic retinoid (ACR), a synthetic retinoid, can prevent HCC development by inhibiting retinoid X receptor ? phosphorylation and improve the prognosis for this malignancy. Supplementation with branched-chain amino acids (BCAA), which are used to improve protein malnutrition in patients with liver cirrhosis, can also reduce the risk of HCC in obese cirrhotic patients. In experimental studies, both ACR and BCAA exert suppressive effects on HCC development and the growth of HCC cells. In particular, combined treatment with ACR and BCAA cooperatively inhibits the growth of HCC cells. Furthermore, ACR and BCAA inhibit liver tumorigenesis associated with obesity and diabetes, both of which are critical risk factors for HCC development. These findings suggest that pharmaceutical and nutraceutical approaches using ACR and BCAA may be promising strategies for preventing HCC and improving the prognosis of this malignancy.
The effect of UVC irradiation was investigated on a model of brain cancer and a model of experimental brain metastasis. For the brain cancer model, brain cancer cells were injected stereotactically into the brain. For the brain metastasis model, lung cancer cells were injected intra-carotidally or stereotactically. The U87 human glioma cell line was used for the brain cancer model, and the Lewis lung carcinoma (LLC) was used for the experimental brain metastasis model. Both cancer cell types were labeled with GFP in the nucleus and RFP in the cytoplasm. A craniotomy open window was used to image single cancer cells in the brain. This double labeling of the cancer cells with GFP and RFP enabled apoptosis of single cells to be imaged at the subcellular level through the craniotomy open window. UVC irradiation, beamed through the craniotomy open window, induced apoptosis in the cancer cells. UVC irradiation was effective on LLC and significantly extended survival of the mice with experimental brain metastasis. In contrast, the U87 glioma was relatively resistant to UVC irradiation. The results of this study suggest the use of UVC for treatment of superficial brain cancer or metastasis.
Hepatocellular carcinoma (HCC) is a slowly developing malignancy postulated to evolve from premalignant lesions in chronically damaged livers. However, it was never established that premalignant lesions actually contain tumor progenitors that give rise to cancer. Here, we describe isolation and characterization of HCC progenitor cells (HcPCs) from different mouse HCC models. Unlike fully malignant HCC, HcPCs give rise to cancer only when introduced into a liver undergoing chronic damage and compensatory proliferation. Although HcPCs exhibit a similar transcriptomic profile to bipotential hepatobiliary progenitors, the latter do not give rise to tumors. Cells resembling HcPCs reside within dysplastic lesions that appear several months before HCC nodules. Unlike early hepatocarcinogenesis, which depends on paracrine IL-6 production by inflammatory cells, due to upregulation of LIN28 expression, HcPCs had acquired autocrine IL-6 signaling that stimulates their in vivo growth and malignant progression. This may be a general mechanism that drives other IL-6-producing malignancies.
Malignant glioma is the most common type of primary central nervous system cancer. Gliomas are very difficult to completely resect due to their invasiveness. In the present study, we compared fluorescence-guided and standard bright-light resection of a human glioma orthotopically implanted in nude mice. U87 human glioma cells, expressing red fluorescent protein (RFP), were injected stereotactically into the nude mouse brain through a craniotomy open window. Two weeks after cancer-cell implantation, gliomas were resected under fluorescence guidance or under bright light. U87-RFP tumors were clearly visualized with a long-working distance fluorescence microscope. Almost all cancer cells were removed using fluorescence-guided navigation without damage to the brain tissue. In contrast, brain tumors were difficult to visualize under bright light and many residual cancer cells remained in the brain after bright-light surgery. Fluorescence-guided surgery significantly extended the survival of the mice compared to those who underwent bright-light surgery. These results suggest that fluorescence-guided surgery has significant potential for brain cancer treatment.
Novel subcellular imaging technology has been developed in order to visualize drug efficacy on single cancer cells in the brain of mice in real time. The efficacy of temozolomide on cancer cells in the brain was determined by observation of subcellular cancer-cell dynamics over time through a craniotomy open window. Dual-color U87 human glioma and Lewis lung carcinoma (LLC) cells, expressing green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm, were imaged through the craniotomy open window 10 days after treatment with temozolomide (100 mg/kg i.p. for five consecutive days). After treatment, dual-color cancer cells with fragmented nuclei were visualized, indicating apoptosis. GFP-expressing apoptotic bodies and the destruction of RFP-expressing cytoplasm were also visualized. In addition, the terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay was used to confirm apoptosis visualized by imaging of the behavior of GFP-labeled cancer-cell nuclei. Tumor volume in the treated group was significantly smaller than in the control group (at day 19, p<0.001). The present study demonstrates technology capable of subcellular real-time imaging in the brain that reports induction of cancer-cell apoptosis by therapeutic treatment. More effective drugs for brain cancer and brain metastasis can be screened and can be identified with this technology.
The ability to visualize cancer cell mitosis and apoptosis in the brain in real time would be of great utility in testing novel therapies. In order to achieve this goal, the cancer cells were labeled with green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm, such that mitosis and apoptosis could be clearly imaged. A craniotomy open window was made in athymic nude mice for real-time fluorescence imaging of implanted cancer cells growing in the brain. The craniotomy window was reversibly closed with a skin flap. Mitosis of the individual cancer cells were imaged dynamically in real time through the craniotomy-open window. This model can be used to evaluate brain metastasis and brain cancer at the subcellular level.
AIM: Protein-energy malnutrition is frequently observed in patients with liver cirrhosis (LC). Non-protein respiratory quotient (npRQ) measured by indirect calorimetry is a good marker to estimate energy malnutrition, and predicts the prognosis of patients with LC. However, measurement of npRQ is limited because of the high cost of indirect calorimetry. Our aim was to find out an alternative marker to npRQ that can be used in the routine clinical setting. METHODS: One hundred and fifty-six patients with LC were enrolled in this study. Indirect calorimetry and blood examinations were conducted after overnight fasting, and anthropometry was performed by an expert dietician. The correlation between npRQ and other parameters were calculated by simple and multiple regression analysis. Receiver-operator curve (ROC) analysis was used to identify the cut-off value that would best predict the threshold npRQ of 0.85. RESULTS: Plasma levels of free fatty acid (FFA) was significantly correlated with npRQ value by simple (r?=?-0.39, P?0.0001) and multiple regression analysis (t?=?-2.96, P?=?0.0052). Free fatty acid rose in parallel with the increasing disease severity as defined by Child-Pugh classification (P?0.05). FFA was also correlated with increasing oxidation rate of fat (r?=?0.38, P?0.0001) and decreasing oxidation rate of carbohydrate (r?=?-0.39, P?0.0001). The cut-off value of FFA to predict npRQ?=?0.85 was 660??Eq/L by ROC analysis. CONCLUSION: FFA is a useful alternative marker to represent npRQ in patients with LC.
Acid sphingomyelinase (ASM) regulates the homeostasis of sphingolipids, including ceramides and sphingosine-1-phosphate (S1P). These sphingolipids regulate carcinogenesis and proliferation, survival, and apoptosis of cancer cells. However, the role of ASM in host defense against liver metastasis remains unclear. In this study, the involvement of ASM in liver metastasis of colon cancer was examined using Asm-/- and Asm+/+ mice that were inoculated with SL4 colon cancer cells to produce metastatic liver tumors. Asm-/- mice demonstrated enhanced tumor growth and reduced macrophage accumulation in the tumor, accompanied by decreased numbers of hepatic myofibroblasts (hMFs), which express tissue inhibitor of metalloproteinase 1 (TIMP1), around the tumor margin. Tumor growth was increased by macrophage depletion or by Timp1 deficiency, but was decreased by hepatocyte-specific ASM overexpression, which was associated with increased S1P production. S1P stimulated macrophage migration and TIMP1 expression in hMFs in vitro. These findings indicate that ASM in the liver inhibits tumor growth through cytotoxic macrophage accumulation and TIMP1 production by hMFs in response to S1P. Targeting ASM may represent a new therapeutic strategy for treating liver metastasis of colon cancer.
Currently-used rodent tumor models, including transgenic tumor models, or subcutaneously growing tumors in mice, do not sufficiently represent clinical cancer. We report here development of methods to obtain a highly clinically-accurate rectal cancer model. This model was established by intrarectal transplantation of mouse rectal cancer cells, stably expressing green fluorescent protein (GFP), followed by disrupting the epithelial cell layer of the rectal mucosa by instilling an acetic acid solution. Early-stage tumor was detected in the rectal mucosa by 6 days after transplantation. The tumor then became invasive into the submucosal tissue. The tumor incidence was 100% and mean volume (±SD) was 1232.4 ± 994.7 mm(3) at 4 weeks after transplantation detected by fluorescence imaging. Spontaneous lymph node metastasis and lung metastasis were also found approximately 4 weeks after transplantation in over 90% of mice. This rectal tumor model precisely mimics the natural history of rectal cancer and can be used to study early tumor development, metastasis, and discovery and evaluation of novel therapeutics for this treatment-resistant disease.
Mesenchymal stromal cells (MSCs) are multipotent adult stem cells which are recruited to the tumor microenvironment (TME) and influence tumor progression through multiple mechanisms. In this study, we examined the effects of MSCs on the tunmorigenic capacity of 4T1 murine mammary cancer cells. It was found that MSC-conditioned medium increased the proliferation, migration, and efficiency of mammosphere formation of 4T1 cells in vitro. When co-injected with MSCs into the mouse mammary fat pad, 4T1 cells showed enhanced tumor growth and generated increased spontaneous lung metastasis. Using in vivo fluorescence color-coded imaging, the interaction between GFP-expressing MSCs and RFP-expressing 4T1 cells was monitored. As few as five 4T1 cells could give rise to tumor formation when co-injected with MSCs into the mouse mammary fat pad, but no tumor was formed when five or ten 4T1 cells were implanted alone. The elevation of tumorigenic potential was further supported by gene expression analysis, which showed that when 4T1 cells were in contact with MSCs, several oncogenes, cancer markers, and tumor promoters were upregulated. Moreover, in vivo longitudinal fluorescence imaging of tumorigenesis revealed that MSCs created a vascularized environment which enhances the ability of 4T1 cells to colonize and proliferate. In conclusion, this study demonstrates that the promotion of mammary cancer progression by MSCs was achieved through the generation of a cancer-enhancing microenvironment to increase tumorigenic potential. These findings also suggest the potential risk of enhancing tumor progression in clinical cell therapy using MSCs. Attention has to be paid to patients with high risk of breast cancer when considering cell therapy with MSCs.
Circulating tumor cells (CTCs) are of great importance for cancer diagnosis, prognosis and treatment. It is necessary to improve the ability to image and analyze them for their biological properties which determine their behavior in the patient. In the present study, using immunomagnetic beads, CTCs were rapidly isolated from the circulation of mice orthotopically implanted with human PC-3 prostate cancer cells stably expressing green fluorescent protein (GFP). The PC-3-GFP CTCs were then expanded in culture in parallel with the parental PC-3-GFP cell line. Both cell types were then inoculated onto the chorioallentoic membrane (CAM) of chick embryos. Eight days later, embryos were harvested and the brains were processed for frozen sections. The IV-100 intravital laser scanning microscope enabled rapid identification of fluorescent metastatic foci within the chick embryonic brain. Inoculation of embryos with PC-3-GFP CTCs resulted in a 3 to 10-fold increase in brain metastasis when compared to those with the parental PC-3-GFP cells (p<0.05 in all animals). Thus, PC-3-GFP CTCs have increased metastatic potential compared to their parental counterparts. Furthermore, the chick embryo represents a rapid, sensitive, imageable assay of metastatic potential for CTCs. The chick embryo assay has future clinical application for individualizing patient therapy based on the metastatic profile of their CTCs.
Nonalcoholic fatty liver disease is one of the most common liver diseases. L-tryptophan and its metabolite serotonin are involved in hepatic lipid metabolism and inflammation. However, it is unclear whether L-tryptophan promotes hepatic steatosis. To explore this issue, we examined the role of L-tryptophan in mouse hepatic steatosis by using a high fat and high fructose diet (HFHFD) model. L-tryptophan treatment in combination with an HFHFD exacerbated hepatic steatosis, expression of HNE-modified proteins, hydroxyproline content, and serum alanine aminotransaminase levels, whereas L-tryptophan alone did not result in these effects. We also found that L-tryptophan treatment increases serum serotonin levels. The introduction of adenoviral aromatic amino acid decarboxylase, which stimulates the serotonin synthesis from L-tryptophan, aggravated hepatic steatosis induced by the HFHFD. The fatty acid-induced accumulation of lipid was further increased by serotonin treatment in cultured hepatocytes. These results suggest that L-tryptophan increases the sensitivity to hepatic steatosis through serotonin production. Furthermore, L-tryptophan treatment, adenoviral AADC introduction, and serotonin treatment induced phosphorylation of the mammalian target of rapamycin (mTOR), and a potent mTOR inhibitor rapamycin attenuated hepatocyte lipid accumulation induced by fatty acid with serotonin. These results suggest the importance of mTOR activation for the exacerbation of hepatic steatosis. In conclusion, L-tryptophan exacerbates hepatic steatosis induced by HFHFD through serotonin-mediated activation of mTOR.
We report here that XPA1 human pancreatic cancer cells are dimorphic. After injection in the spleen, XPA1 cells isolated from the primary tumor in the spleen were predominantly round; while cells isolated from the resulting liver metastasis and ascites were comprised of both round- and spindle-shaped cell types. Cancer cells previously grown in the spleen and re-implanted in the spleen developed large primary tumors in the spleen only. Cancer cells isolated from liver metastasis and re-transplanted to the spleen resulted in a primary tumor in the spleen and liver metastasis. Cancer cells derived from ascites and re-transplanted to the spleen developed primary tumors in the spleen and distant metastasis in the liver, lung, and diaphragm in addition to ascites formation. Spindle and round cells were differentially labeled with fluorescent proteins of different colors. After co-injection of the two cell types in the spleen, cells were isolated from the primary tumors, liver metastasis, and ascites and analyzed by color-coded fluorescence microscopy and fluorescence-activated cell sorting (FACS). No significant differences between the percentages of spindle-shaped and round cancer cells in the primary tumor and the liver metastasis were observed. However, spindle-shaped cancer cells were enriched in the ascites. One hundred percent of the spindle-shaped and round cancer cells expressed CD44, suggesting that morphology and metastatic behavior rather than CD44 expression can distinguish the stem-like cells of the XPA1 pancreatic cancer cell line. The spindle-shaped cancer cells had the greater capability for distant metastasis and ascites formation, suggesting they are stem-like cells, which can be readily targeted for therapy.
The tumor microenvironment (TME) is critical for tumor growth and progression. However, the formation of the TME is largely unknown. This report demonstrates a color-coded imaging model in which the development of the TME can be visualized. In order to image the TME, a green fluorescent protein (GFP)-expressing mouse was used as the host which expresses GFP in all organs but not the parenchymal cells of the liver. Non-colored HCT-116 human colon cancer cells were injected in the spleen of GFP nude mice which led to the formation of experimental liver metastasis. TME formation resulting from the liver metastasis was observed using the Olympus OV100 small animal fluorescence imaging system. HCT-116 cells formed tumor colonies in the liver 28 days after cell transplantation to the spleen. GFP-expressing host cells were recruited by the metastatic tumors as visualized by fluorescence imaging. A desmin positive area increased around and within the liver metastasis over time, suggesting cancer-associated fibroblasts (CAFs) were recruited by the liver metastasis which have a role in tumor progression. The color-coded model of the TME enables its formation to be visualized at the cellular level in vivo, in real-time. This imaging model of the TME should lead to new visual targets in the TME.
Acid sphingomyelinase (ASM) regulates the homeostasis of sphingolipids, including ceramides and sphingosine-1-phosphate (S1P). Because sphingolipids regulate AKT activation, we investigated the role of ASM in hepatic glucose and lipid metabolism. Initially, we overexpressed ASM in the livers of wild-type and diabetic db/db mice by adenovirus vector (Ad5ASM). In these mice, glucose tolerance was improved, and glycogen and lipid accumulation in the liver were increased. Using primary cultured hepatocytes, we confirmed that ASM increased glucose uptake, glycogen deposition, and lipid accumulation through activation of AKT and glycogen synthase kinase-3?. In addition, ASM induced up-regulation of glucose transporter 2 accompanied by suppression of AMP-activated protein kinase (AMPK) phosphorylation. Loss of sphingosine kinase-1 (SphK1) diminished ASM-mediated AKT phosphorylation, but exogenous S1P induced AKT activation in hepatocytes. In contrast, SphK1 deficiency did not affect AMPK activation. These results suggest that the SphK/S1P pathway is required for ASM-mediated AKT activation but not for AMPK inactivation. Finally, we found that treatment with high-dose glucose increased glycogen deposition and lipid accumulation in wild-type hepatocytes but not in ASM(-/-) cells. This result is consistent with glucose intolerance in ASM(-/-) mice. In conclusion, ASM modulates AKT activation and AMPK inactivation, thus regulating glucose and lipid metabolism in the liver.
In this study, we demonstrate that the differential behavior, including malignancy and chemosensitivity, of cancer stem-like and non-stem cells can be simultaneously distinguished in the same tumor in real time by color-coded imaging. CD133(+) Huh-7 human hepatocellular carcinoma (HCC) cells were considered as cancer stem-like cells (CSCs), and CD133(-) Huh-7 cells were considered as non-stem cancer cells (NSCCs). CD133(+) cells were isolated by magnetic bead sorting after Huh-7 cells were genetically labeled with green fluorescent protein (GFP) or red fluorescent protein (RFP). In this scheme, CD133(+) cells were labeled with GFP and CD133(-) cells were labeled with RFP. CSCs had higher proliferative potential compared to NSCCs in vitro. The same number of GFP CSCs and the RFP NSCCs were mixed and injected subcutaneously or in the spleen of nude mice. CSCs were highly tumorigenic and metastatic as well as highly resistant to chemotherapy in vivo compared to NSCCs. The ability to specifically distinguish stem-like cancer cells in vivo in real time provides a visual target for prevention of metastasis and drug resistance.
Engelbreth-Holm-Swarm (EHS) gel has been reported to maintain the mature hepatocyte phenotypes in primary cultured hepatocytes. We investigated the effect of EHS gel on the differentiation of fetal liver cells, which contain stem/progenitor cells. The isolated fetal liver cells cultured on EHS gel formed a spherical shape and increased liver-specific gene expressions compared with cells cultured on collagen. The hepatic progenitor cells that were transplanted subcutaneously to BALB/c nude mice could survive and express hepatocyte marker alpha-fetoprotein when the cells were suspended with EHS gel. These findings demonstrate that EHS gel supports cytodifferentiation from immature progenitor cells to hepatocytes and maintain its differentiated phenotypes in vitro and in vivo.
Cancer cells, with and without fluorescent protein expression, were irradiated with various doses of UVC (100, 400, and 600 J/m(2)). Dual-color Lewis lung carcinoma cells (LLC) and U87 human glioma cells, expressing GFP in the nucleus and RFP in the cytoplasm and non-colored LLC and U87 cells were cultured in 96-well plates. Eight hours after seeding, the cells were irradiated with the various doses of UVC. The resulting cell number was determined after 24 hours. Compared to non-colored LLC cells, the number of dual-color LLC cells decreased significantly due to UVC irradiation with 100 J/m(2) (p=0.003). Although there was no significant difference in the number of dual-color and non-colored U87 cells after 100 J/m(2) UVC irradiation (p=0.852), the number of dual-color U87 cells decreased significantly with respect to non-colored cells due to UVC irradiation with 400 J/m(2) and 600 J/m(2) (p=0.011 and p=0.009, respectively). Thus, both dual-color LLC and dual-color U87 cells were more sensitive to UVC light than non-colored LLC and U87 cells. These results suggest that the expression of fluorescent proteins in cancer cells can enhance photodynamic therapy (PDT) using UVC and possibly with other wavelengths of light as well.
Exosomes play an important role in cell-to-cell communication to promote tumor metastasis. In order to image the fate of cancer-cell-derived exosomes in orthotopic nude mouse models of breast cancer, we used green fluorescent protein (GFP)-tagged CD63, which is a general marker of exosomes. Breast cancer cells transferred their own exosomes to other cancer cells and normal lung tissue cells in culture. In orthotopic nude-mouse models, breast cancer cells secreted exosomes into the tumor microenvironment. Tumor-derived exosomes were incorporated into tumor-associated cells as well as circulating in the blood of mice with breast cancer metastases. These results suggest that tumor-derived exosomes may contribute to forming a niche to promote tumor growth and metastasis. Our results demonstrate the usefulness of GFP imaging to investigate the role of exosomes in cancer metastasis.
In order to individualize and therefore have more effective treatment for pancreatic cancer, we have developed a multicolor, imageable, orthotopic mouse model for individual patients with pancreatic cancer by passaging their tumors through transgenic nude mice expressing green fluorescent protein (GFP) and red fluorescent protein (RFP). The tumors acquired brightly fluorescent stroma from the transgenic host mice, which was stably associated with the tumors through multiple passages. In the present study, pancreatic cancer patient tumor specimens were initially established in NOD.CB17-Prkdc(scid)/NcrCrl (NOD/SCID) mice. The tumors were then passaged orthotopically into transgenic nude mice ubiquitously expressing GFP and subsequently to nude mice ubiquitously expressing RFP. The tumors, with very bright GFP and RFP stroma, were then orthotopically passaged to non-transgenic nude mice. It was possible to image the brightly fluorescent tumors non-invasively longitudinally as they progressed in the non-transgenic nude mice. This non-invasive imageable tumorgraft model will be valuable to screen for effective treatment options for individual patients with pancreatic cancer, as well as for the discovery of improved agents for this treatment-resistant disease.
Traditional Chinese Medicine (TCM) has been used for thousands of years, including treatment for cancer. Use of modern technology and the scientific method to evaluate the efficacy of TCM for cancer should enable its more widespread use. In the present study, the efficacy of the TCM tubeimu, extracted from the tuber of the plant Bolbostemma paniculatum, on the MDA-MB-231 human breast cancer cell line was evaluated. The MDA-MB-231 cell line was engineered to express red fluorescent protein (RFP) in the cytoplasm and green fluorescent protein (GFP) linked to histone H2B in the nucleus, which allows real-time imaging of nuclear-cytoplasmic dynamics. Apoptosis was readily visualized in these cells by nuclear shape changes and fragmentation. The MDA-MB-231 RFP-GFP cells were cultured either in two-dimensions on plastic or in three-dimensions on Gelfoam®. Cells were treated with a dichloromethane extract of fresh tubeimu. Apoptosis was further monitored by DNA fragmentation determined by gel electrophoresis. Tubeimu induced apoptosis of MDA-MB-231 cells, as observed by fluorescence microscopy, as early as 24 hours of treatment in vitro in two-dimensional culture. By 48 hours treatment, DNA fragmentation could be observed. The frequency of apoptosis increased through at least 72 hours treatment, with most of the cells being killed. Tubeimu also induced apoptosis of MDA-MB-231 cells in three-dimensional culture on Gelfoam®, but to a lesser extent than in 2D culture. The results of the present study indicate the potential of tubeimu in breast cancer therapy.
We have developed the genetically-modified Salmonella typhimurium A1-R strain that selectively targets tumors. S. typhimurium A1-R is auxotrophic for Leu and Arg, which precludes it from growing continuously in normal tissues but allows high tumor virulence. We report here the efficacy and safety of three different routes of S. typhimurium A1-R administration: oral (p.o.), intravenous (i.v.), and intra-tumoral (i.t.) in nude mice with orthotopic human breast cancer. Nude mice with MDA-MB-435 human breast cancer, expressing red fluorescent protein (RFP), were administered S. typhimurium A1-R by one of the three routes: [p.o.: 2×10(8) colony forming units (CFU)/200 ?l; i.v.: 2.5×10(7) CFU/100 ?l; i.t.: 2.5×10(7) CFU/50 ?l] twice a week. Tumor growth was monitored by fluorescence imaging and caliper measurement in two dimensions. S. typhimurium A1-R targeted tumors at much higher levels than normal organs after all three routes of administration. The fewest bacteria were detected in normal organs after p.o. administration, which suggests that p.o. administration has the highest safety. The i.v. route had the greatest antitumor efficacy. There were no obvious toxic effects on the host with any of the routes of administration. The results of this study suggest that p.o. administration was the most safe to the host and the i.v. route was most effective for tumor targeting with S. typhimurium A1-R.
We have previously demonstrated the increased metastatic potential of human prostate cancer circulating tumor cells (CTC), compared to their parental cells, in both orthotopic mouse models and the chick embryo model. In the current study, we asked whether an extracellular matrix (ECM), produced by human foreskin fibroblasts in culture, could inhibit PC-3 human prostate cancer CTC metastasis in the chick embryo model. The chorioallantoic membranes (CAM) of 18 chicken embryos were inoculated with either PC-3 human prostate cancer cells or PC-3 CTCs, both stably expressing green fluorescent protein (GFP). Embryos were divided into six groups: PC-3 parental-cell control; PC-3 plus soluble ECM; PC-3 parental cells plus semi-solid ECM; PC-3 CTC control; PC-3 CTC plus soluble ECM, and PC-3 CTC plus semi-solid ECM. Twelve hours following inoculation of the cells, a single dose of 100 ?l of either soluble or semi-solid ECM was added to the appropriate group. Embryo brains were removed on day 8 post-inoculation, and were processed for cryosectioning. Imaging was performed on the cryosections using a scanning laser microscope in order to count metastatic foci. PC-3 controls had an average of 11.1 metastatic foci compared to 2.55 in the PC-3 plus soluble ECM group and 2.76 (p<0.0001) in the PC-3 plus semi-solid ECM group (p<0.0001). ECM treatment had even greater efficacy on the CTC cells, with an average of 30.9 metastatic foci in the CTC controls compared to 4.38 in the CTC plus soluble ECM group (p<0.0001) and 4.18 in the CTC plus semi-solid ECM group (p<0.0001). The results demonstrate that reduction of CTC metastatic potential is possible, in this case with an ECM produced by human foreskin fibroblasts in culture.
Pancreatic-cancer-patient tumor specimens were initially established subcutaneously in NOD/SCID mice immediately after surgery. The patient tumors were then harvested from NOD/SCID mice and passaged orthotopically in transgenic nude mice ubiquitously expressing red fluorescent protein (RFP). The primary patient tumors acquired RFP-expressing stroma. The RFP-expressing stroma included cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs). Further passage to transgenic nude mice ubiquitously expressing green fluorescent protein (GFP) resulted in tumors that acquired GFP stroma in addition to their RFP stroma, including CAFs and TAMs as well as blood vessels. The RFP stroma persisted in the tumors growing in the GFP mice. Further passage to transgenic nude mice ubiquitously expressing cyan fluorescent protein (CFP) resulted in tumors acquiring CFP stroma in addition to persisting RFP and GFP stroma, including RFP- and GFP-expressing CAFs, TAMs and blood vessels. This model can be used to image progression of patient pancreatic tumors and to visually target stroma as well as cancer cells and to individualize patient therapy.
Tumors from pancreatic cancer patients were established in NOD/SCID mice immediately after surgery and subsequently passaged orthotopically in transgenic nude mice ubiquitously expressing green fluorescent protein (GFP). The primary patient tumors acquired GFP-expressing stroma. Subsequent liver metastases, and disseminated peritoneal metastases maintained the stroma from the primary tumor, and possibly recruited additional GFP-expressing stroma, resulting in their very bright fluorescence. The GFP-expressing stroma included cancer-associated fibroblasts and tumor-associated macrophages in both the primary and metastatic tumors. This imageable model of metastasis from a patient-tumor is an important advance over patient "tumorgraft" models currently in use, which are implanted subcutaneously, do not metastasize and are not imageable. The new imageable model of patient pancreatic cancer metastasis provides unique opportunities to identify current and novel antimetastatic therapeutics for individual patients.
The present study examined the effects of types of liver resection on the growth of liver and lung metastases.
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Journal of Visualized Experiments
What is Visualize?
JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.
How does it work?
We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.
Video X seems to be unrelated to Abstract Y...
In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.