Journal Article

PC-3M-luc2, PC3M-luc2, IVIS, Prostate Cancer, Bioware

Zoledronic acid (ZOL) is a drug whose potent anti-cancer activity is limited by its short plasma half-life and rapid uptake and accumulation within bone. We have recently proposed new delivery systems to avoid ZOL accumulation into the bone, thus improving extra-skeletal bioavailability. In this work, we have compared the technological and anti-cancer features of either ZOL-containing self-assembly PEGylated nanoparticles (NPs) or ZOL-encapsulating PEGylated liposomes (LIPO-ZOL). ZOL-containing NPs showed superior technological characteristics in terms of mean diameter, size distribution, and ZOL encapsulation efficiency, compared to LIPO-ZOL. Moreover, the anti-cancer activity of NPs in nude mice xenografted with prostate cancer PC3 cells was higher than that one induced by LIPO-ZOL. In addition, NPs induced the complete remission of tumour xenografts and an increase of survival time higher than that one observed with LIPO-ZOL. It has also to be considered that PC3 tumour xenografts were almost completely resistant to the anti-cancer effects induced by free ZOL. Both nanotechnological products did not induce toxic effects not affecting the mice weight nor inducing deaths. Moreover, the histological examination of some vital organs such as liver, kidney and spleen did not find any changes in terms of necrotic effects or modifications in the inflammatory infiltrate. On the other hand, NPs but not LIPO-ZOL caused a statistically significant reduction of the tumour associated macrophages (TAM) in tumour xenografts. This effect was paralleled by a significant increase of both necrotic and apoptotic indexes. The effects of the NPs were also higher in terms of neo-angiogenesis inhibition. These results suggest the future preclinical development of ZOL-encapsulating NPs in the treatment of human cancer.

Journal Article

GL261-luc2, IVIS, Glioma, Biolumninescence imaging

The mouse glioma 261 (GL261) is recognized as an in vivo model system that recapitulates many of the features of human glioblastoma multiforme (GBM). The cell line was originally induced by intracranial injection of 3-methyl-cholantrene into a C57BL/6 syngeneic mouse strain (1); therefore, immunologically competent C57BL/6 mice can be used. While we use GL261, the following protocol can be used for the implantation and monitoring of any intracranial mouse tumor model. GL261 cells were engineered to stably express firefly luciferase (GL261-luc). We also created the brighter GL261-luc2 cell line by stable transfection of the luc2 gene expressed from the CMV promoter. C57BL/6-cBrd/cBrd/Cr mice (albino variant of C57BL/6) from the National Cancer Institute, Frederick, MD were used to eliminate the light attenuation caused by black skin and fur. With the use of albino C57BL/6 mice; in vivo imaging using the IVIS Spectrum in vivo imaging system is possible from the day of implantation (Caliper Life Sciences, Hopkinton, MA). The GL261-luc and GL261-luc2 cell lines showed the same in vivo behavior as the parental GL261 cells. Some of the shared histological features present in human GBMs and this mouse model include: tumor necrosis, pseudopalisades, neovascularization, invasion, hypercellularity, and inflammation (1). Prior to implantation animals were anesthetized by an intraperitoneal injection of ketamine (50 mg/kg), xylazine (5 mg/kg) and buprenorphine (0.05 mg/kg), placed in a stereotactic apparatus and an incision was made with a scalpel over the cranial midline. A burrhole was made 0.1mm posterior to the bregma and 2.3mm to the right of the midline. A needle was inserted to a depth of 3mm and withdrawn 0.4mm to a depth of 2.6mm. Two mul of GL261-luc or GL261-luc2 cells (10(7) cells/ml) were infused over the course of 3 minutes. The burrhole was closed with bonewax and the incision was sutured. Following stereotactic implantation the bioluminescent cells are detectable from the day of implantation and the tumor can be analyzed using the 3D image reconstruction feature of the IVIS Spectrum instrument. Animals receive a subcutaneous injection of 150mug luciferin /kg body weight 20 min prior to imaging. Tumor burden is quantified using mean tumor bioluminescence over time. Tumor-bearing mice were observed daily to assess morbidity and were euthanized when one or more of the following symptoms are present: lethargy, failure to ambulate, hunched posture, failure to groom, anorexia resulting in >10% loss of weight. Tumors were evident in all of the animals on necropsy.

Journal Article

BxPC-3, BxPC-3-luc2, IVIS, Achyranthes; Animals; Antineoplastic Agents, Phytogenic/pharmacology/*therapeutic use; Apoptosis/*drug effects; Caspase 3/genetics/metabolism; Gene Expression/drug effects; Humans; Injections, Intraperitoneal; Medicine, Ayurvedic; Mice; Mice, Nude; Pancreatic Neoplasms/*drug therapy/genetics/metabolism; Phosphorylation; *Phytotherapy; Plant Extracts/pharmacology/*therapeutic use; Plant Leaves; Proto-Oncogene Proteins c-akt/metabolism; RNA, Messenger/metabolism; Xenograft Model Antitumor Assays

ETHNOPHARMACOLOGICAL RELEVANCE: Achyranthes aspera (Family Amaranthacea) is used for cancer therapy by ayurvedic medical practitioners in India. However, due to the non formal nature of its use, there are no systematic studies validating its medicinal properties. Thus, it's utility as an anti cancer agent remains anecdotal. Earlier, we demonstrated A. aspera to exhibit time and dose-dependent preferential cytotoxicity to cultured human pancreatic cancer cells. In this report we validate in vivo anti tumor properties of A. aspera. MATERIALS AND METHODS: The in vivo anti tumor activity of leaf extract (LE) was tested by intraperitoneal (IP) injections into athymic mice harboring human pancreatic tumor subcutaneous xenograft. Toxicity was monitored by recording changes in behavioral, histological, hematological and body weight parameters. RESULTS: Dosing LE to athymic mice by I.P. injection for 32 days showed no adverse reactions in treated mice. Compared to the control set, IP administration of LE to tumor bearing mice significantly reduced both tumor weight and volume. Gene expression analysis using Real time PCR methods revealed that LE significantly induced caspase-3 mRNA (p<0.001) and suppressed expression of the pro survival kinase Akt-1 (p<0.05). TUNEL assay and immunohistochemistry confirmed apoptosis induction by activation of caspase-3 and inhibiting Akt phosphorylation in treated sets. These results are in agreement with RT PCR data. CONCLUSION: Taken together, these data suggest A. aspera to have potent anti cancer property.

Journal Article

B16-F10-luc2, B16F10-luc2, IVIS

mAb therapy for experimental metastatic melanoma relies on activating receptors for the Fc portion of IgG (FcgammaR). Opposing results on the respective contribution of mouse FcgammaRI, FcgammaRIII, and FcgammaRIV have been reported using the gp75-expressing B16 melanoma and the protective anti-gp75 mAb TA99. We analyzed the contribution of FcgammaRs to this therapy model using bioluminescent measurement of lung metastases loads, novel mouse strains, and anti-FcgammaR blocking mAbs. We found that the TA99 mAb-mediated effects in a combination therapy using cyclophosphamide relied on activating FcgammaRs. The combination therapy, however, was not more efficient than mAb therapy alone. We demonstrate that FcgammaRI and, unexpectedly, FcgammaRIII contributed to TA99 mAb therapeutic effects, whereas FcgammaRIV did not. Therefore, FcgammaRIII and FcgammaRI are, together, responsible for anti-gp75 mAb therapy of B16 lung metastases. Our finding that mouse FcgammaRIII contributes to Ab-induced tumor reduction correlates with clinical data on its human functional equivalent human FcgammaRIIIA (CD16A).

Journal Article

4T1-luc2, IVIS, Bioluminescence

The vacuolar H+-ATPase (V-ATPase), a multisubunit proton pump, has come into focus as an attractive target in cancer invasion. However little is known about the role of V-ATPase in cell death and especially the underlying mechanisms remain mostly unknown. We used the myxobacterial macrolide archazolid B, a potent inhibitor of the V-ATPase, as an experimental drug as well as a chemical tool to decipher V-ATPase related cell death signaling. We found that archazolid induced apoptosis in highly invasive tumor cells at nanomolar concentrations which was executed by the mitochondrial pathway. Prior to apoptosis induction archazolid lead to the activation of a cellular stress response including activation of the hypoxia-inducible factor-1 alpha (HIF1alpha) and autophagy. Autophagy was induced at low concentrations of archazolid that do not alter pH in lysosomes and was shown by degradation of p62 or fusion of autophagosomes with lysosomes. HIF1alpha was induced due to energy stress shown by a decline of the ATP level and followed by a shut down of energy consuming processes. As silencing HIF1alpha increases apoptosis, the cellular stress response was suggested to be a survival mechanism. We conclude that archazolid leads to energy stress which activates adaptive mechanisms like autophagy mediated by HIF1alpha and finally leads to apoptosis. We propose V-ATPase as a promising drugable target in cancer therapy caught up at the interplay of apoptosis, autophagy and cellular/metabolic stress.