3,324 research outputs found

    Traditional Chinese medicine herbal mixture LQ arrests FUCCI-expressing HeLa cells in Gā‚€/Gā‚ phase in 2D plastic, 2.5D Matrigel, and 3D Gelfoam culture visualized with FUCCI imaging.

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    We used the fluorescence ubiquitination-based cell cycle indicator (FUCCI) to monitor cell cycle arrest after treatment of FUCCI-expressing HeLa cells (FUCCI-HeLa) with a traditional Chinese medicine (TCM) herbal mixture LQ, previously shown to have anti-tumor and anti-metastatic activity in mouse models. Paclitaxel was used as the positive control. In 2D monolayer culture, the untreated control had approximately 45% of the cells in S/Gā‚‚/M phase. In contrast, the LQ-treated cells (9 mg/ml) were mostly in the Gā‚€/Gā‚ (>90%) after 72 hours. After treatment with paclitaxel (0.01 Ī¼m), for 72 hours, 95% of the cells were in S/Gā‚‚/M. In 2.5D Matrigel culture, the colonies in the untreated control group had 40% of the cells in S/Gā‚‚/M. LQ arrested the cells in Gā‚€/Gā‚ after 72 hours. Paclitaxel arrested almost all the cells in S/Gā‚‚/M after 72 hours. In 3D Gelfoam culture, the untreated control culture had approximately 45% of cells in Gā‚‚/M. In contrast, the LQ-treated cells were mostly in Gā‚€/Gā‚ phase (>80%) after 72 hours treatment. Paclitaxel resulted in 90% of the cells arrested in S/Gā‚‚/M after 72 hours. The present report suggests the non-toxic LQ has potential to maintain cancers in a quiescent state for long periods of time

    Targeting the insulin growth factor-1 receptor with fluorescent antibodies enables high resolution imaging of human pancreatic cancer in orthotopic mouse models.

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    The goal of the present study was to determine whether insulin-like growth factor-1 receptor (IGF-1R) antibodies, conjugated with bright fluorophores, could enable visualization of pancreatic cancer in orthotopic nude mouse models. IGF-1R antibody (clone 24-31) was conjugated with 550 nm or 650 nm fluorophores. Western blotting confirmed the expression of IGF-1R in Panc-1, BxPC3, and MIAPaCa-2 human pancreatic cancer cell lines. Labeling with fluorophore-conjugated IGF-1R antibody demonstrated fluorescent foci on the membrane of the pancreatic cancer cells. Subcutaneous Panc-1, BxPC-3, and MIA PaCa-2 tumors became fluorescent after intravenous administration of fluorescent IGF-1R antibodies. Orthotopically-transplanted BxPC-3 tumors became fluorescent with the conjugated IGF-1R antibodies, and were easily visible with intravital imaging. Gross and microscopic ex vivo imaging of resected pancreatic tumor and normal pancreas confirmed that fluorescence indeed came from the membrane of cancer cells, and it was stronger from the tumor than the normal tissue. The present study demonstrates that fluorophore-conjugated IGF-1R antibodies can visualize pancreatic cancer and it can be used with various imaging devices such as endoscopy and laparoscopy for diagnosis and fluorescence-guided surgery

    Two-photon imaging of cancer cell extravasation in live mice

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    Abstract MDA-MB-231 breast cancer cells were engineered to express cytoplasmic paxillin-GFP and nuclear H2B-mCherry. In order to image extravasation, the cancer cells were injected in the blood stream of nude mice. Using 2-photon excitation microscopy we can simultaneously excite the two probes and also visualize the autofluorescence of tissues. A skin flap was opened to visualize blood vessels and recognize the position of the cancer cells. Two-photon imaging showed that after an initial phase in which the cells are non-adherent, some cells spread on the internal surface of the capillaries. Days later some cells started to appear on the external side of the capillary. The extravasated cells extend very long protrusions into the tissue. The goal was to determine if at the end of the long protrusion, if it is possible to observe the formation of focal adhesions by imaging paxillin-GFP. Preliminary results show that when cells start to adhere to the blood vessel wall they form focal adhesions as determined by the characteristic elongated features observed in the paxillin-GFP channel. New approaches will allow the tracking of the tip of the protrusion to determine if focal adhesions are forming there as the cells extravasate. This is important in establishing the mechanism of cell extravasation and migration in tissues. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1412. doi:10.1158/1538-7445.AM2011-141

    The Rocky Road to Energy Dominance: The Executive Branchā€™s Limited Authority to Modify and Revoke Withdrawals of Federal Lands from Mineral Production

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    The Trump Administrationā€™s implementation of its America First Energy Plan, whose goal is achieving U.S. ā€œenergy dominance,ā€ has relied heavily upon public mineral development. Mineral development on federal lands is largely governed by statute. The statutory legal mechanisms by which the Executive Branch can ā€œopenā€ or ā€œcloseā€ an area of federal lands to mineral development, whether onshore or offshore, are withdrawal, modification, and revocation.The Federal Land Policy and Management Act (FLPMA) and the Outer Continental Shelf Lands Act (OCSLA) are the primary statutes that govern onshore and offshore mineral development on over 2 billion acres of federal lands. Both FLPMA and OCSLA authorize withdrawals, which the Executive can use to place federal lands off limits to mineral development. FLPMA also authorizes modifications and revocations, which can remove constraints on such development. The Trump Administration has relied on both statutes in its quest to expand the areas that are available for private mineral disposition through modification or revocation of withdrawals by prior administrations.The authority provided by FLPMA and OCSLA to determine the availability of federal lands for mineral development is subject to a series of substantive and procedural constraints. Because it regards those constraints as undesirable shackles on the implementation of its mineral development policies, and consistent with its expansive view of Executive Branch power in almost all contexts, the Administration has not been content to rely on statutory authorization to modify and revoke development-precluding withdrawals. Instead, it has also invoked non-statutory, implied or inherent authority to open vast areas of federal lands to oil and gas, coal, and other mineral development.The paucity of judicial precedent governing the parameters of statutory and non-statutory Executive Branch authority to reopen lands previously placed off limits to mineral development raises significant questions about the legality of the Administrationā€™s efforts to alter the status of protected lands and resources. Although the Administration apparently regards downsizing or revocation of withdrawals by previous administrations as a quick and effective way to open up vast new acreage to mineral development, the legal basis for its actions is tenuous at best.This Article examines both statutory and non-statutory mechanisms for determining the availability of federal onshore and offshore lands for uses such as mineral exploration and development. It identifies the constraints that FLPMA and OCSLA impose on revocation or modification of previous withdrawals. It also explores the parameters of non-statutory Executive mineral disposition authority and assesses the legality of the significant Trump Administration withdrawal modification and revocation efforts to date. It concludes that Congress has eliminated any implied or inherent withdrawal, revocation, or modification authority that may once have existed. It also finds that the most prominent and controversial of the Trump withdrawal modifications and revocations exceeded the authority the Executive Branch retains under FLPMA and OCSLA. As a result, that the Trump Administrationā€™s unauthorized pursuit of energy dominance should result in judicial invalidation

    The disintegrin echistatin in combination with doxorubicin targets high-metastatic human osteosarcoma overexpressing Ī±Ī½Ī²3 integrin in chick embryo and nude mouse models.

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    Echistatin, a cyclic RGD peptide, which is an antagonist of Ī±vĪ²3 integrin (disintegrin), inhibited human osteosarcoma in the chick chorioallontoic membrane (CAM) model and tumor growth and pulmonary metastases in a nude mouse orthotopic model. A high-metastatic variant of human osteosarcoma, 143B-LM4, overexpressing Ī±vĪ²3 integrin was used. Tumor angiogenesis by high-metastatic variant 143B-LM4 cells in the CAM was significantly inhibited by echistatin (P<0.05) as was overall growth. A doxorubicin (DOX)-echistatin combination inhibited orthotopic tumor growth compared to untreated control (P<0.01) or DOX alone (P<0.05) in nude mice. Tumor-bearing mice treated with the DOX-echistatin combination survived longer than those treated with DOX alone or control PBS (P<0.01 and P<0.01, respectively). Echistatin also inhibited experimental lung metastasis of 143B-LM4 cells in nude mice. These results suggest that DOX in combination with a disintegrin has potential to treat osteosarcoma and that Ī±vĪ²3 integrin may be a target for osteosarcoma

    Fluorescent-Antibody Targeting of Insulin-Like Growth Factor-1 Receptor Visualizes Metastatic Human Colon Cancer in Orthotopic Mouse Models.

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    Fluorescent-antibody targeting of metastatic cancer has been demonstrated by our laboratory to enable tumor visualization and effective fluorescence-guided surgery. The goal of the present study was to determine whether insulin-like growth factor-1 receptor (IGF-1R) antibodies, conjugated with bright fluorophores, could enable visualization of metastatic colon cancer in orthotopic nude mouse models. IGF-1R antibody (clone 24-31) was conjugated with 550 nm, 650 nm or PEGylated 650 nm fluorophores. Subcutaneous, orthotopic, and liver metastasis models of colon cancer in nude mice were targeted with the fluorescent IGF-1R antibodies. Western blotting confirmed the expression of IGF-1R in HT-29 and HCT 116 human colon cancer cell lines, both expressing green fluorescent protein (GFP). Labeling with fluorophore-conjugated IGF-1R antibody demonstrated fluorescent foci on the membrane of colon cancer cells. Subcutaneously- and orthotopically-transplanted HT-29-GFP and HCT 116-GFP tumors brightly fluoresced at the longer wavelengths after intravenous administration of fluorescent IGF-1R antibodies. Orthotopically-transplanted HCT 116-GFP tumors were brightly labeled by fluorescent IGF-1R antibodies such that they could be imaged non-invasively at the longer wavelengths. In an experimental liver metastasis model, IGF-1R antibodies conjugated with PEGylated 650 nm fluorophores selectively highlighted the liver metastases, which could then be non-invasively imaged. The IGF-1R fluorescent-antibody labeled liver metastases were very bright compared to the normal liver and the fluorescent-antibody label co-located with green fluorescent protein (GFP) expression of the colon cancer cells. The present study thus demonstrates that fluorophore-conjugated IGF-1R antibodies selectively visualize metastatic colon cancer and have clinical potential for improved diagnosis and fluorescence-guided surgery

    Selective methioninase-induced trap of cancer cells in S/G2 phase visualized by FUCCI imaging confers chemosensitivity.

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    A major impediment to the response of tumors to chemotherapy is that the large majority of cancer cells within a tumor are quiescent in G0/G1, where cancer cells are resistant to chemotherapy. To attempt to solve this problem of quiescent cells in a tumor, cancer cells were treated with recombinant methioninase (rMETase), which selectively traps cancer cells in S/G2. The cell cycle phase of the cancer cells was visualized with the fluorescence ubiquitination-based cell cycle indicator cell cycle indicator (FUCCI). At the time of rMETase-induced S/G2-phase blockage, identified by the cancer cells' green fluorescence by FUCCI imaging, the cancer cells were administered S/G2-dependent chemotherapy drugs, which interact with DNA or block DNA synthesis such as doxorubicin, cisplatin, or 5-fluorouracil. Treatment of cancer cells with drugs only, without rMETase-induced S/G2 phase blockage, led to the majority of the cancer-cell population being blocked in G0/G1 phase, identified by the cancer cells becoming red fluorescent in the FUCCI system. The G0/G1 blocked cells were resistant to the chemotherapy. In contrast, trapping of cancer cells in S/G2 phase by rMETase treatment followed by FUCCI-imaging-guided chemotherapy was highly effective in killing the cancer cells

    Adenoviral targeting of malignant melanoma for fluorescence-guided surgery prevents recurrence in orthotopic nude-mouse models.

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    Malignant melanoma requires precise resection in order to avoid metastatic recurrence. We report here that the telomerase-dependent, green fluorescent protein (GFP)-containing adenovirus OBP-401 could label malignant melanoma with GFP in situ in orthotopic mouse models. OBP-401-based fluorescence-guided surgery (FGS) resulted in the complete resection of malignant melanoma in the orthotopic models, where conventional bright-light surgery (BLS) could not. High-dose administration of OBP-401 enabled FGS without residual cancer cells or recurrence, due to its dual effect of cancer-cell labeling with GFP and killing
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