gant-61 and Adenocarcinoma

Current conventional mono and combination therapeutic strategies often fail to target breast cancer tissue effectively due to tumor heterogeneity comprising cancer stem cells (CSCs) and bulk tumor cells. This is further associated with drug toxicity and resistivity in the long run. A nanomedicine platform incorporating combination anti-cancer treatment might overcome these challenges and generate synergistic anti-cancer effects and also reduce drug toxicity. GANT61 and curcumin were co-delivered via polymeric nanoparticles (NPs) for the first time to elicit enhanced anti-tumor activity against heterogeneous breast cancer cell line MCF-7. We adopted the single-emulsion-solvent evaporation method for the preparation of the therapeutic NPs. The GANT61-curcumin PLGA NPs were characterized for their size, shape and chemical properties, and anti-cancer cell studies were undertaken for the plausible explanation of our hypothesis. The synthesized GANT61-curcumin PLGA NPs had a spherical, smooth surface morphology, and an average size of 347.4 d. nm. The NPs induced cytotoxic effects in breast cancer cells at a mid-minimal dosage followed by cell death via autophagy and apoptosis, reduction in their target protein expression along with compromising the self-renewal property of CSCs as revealed by their in vitro cell studies. The dual-drug NPs thus provide a novel perspective on aiding existing anti-cancer nanomedicine therapies to target a heterogeneous tumor mass effectively.

Topics: Adenocarcinoma; Animals; Apoptosis; Autophagy; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cell Survival; Curcumin; Drug Liberation; Endocytosis; Female; Humans; MCF-7 Cells; Mice; Nanoparticles; Particle Size; Phosphatidylinositol 3-Kinases; Photoelectron Spectroscopy; Polylactic Acid-Polyglycolic Acid Copolymer; Proto-Oncogene Proteins c-akt; Pyridines; Pyrimidines; Spectroscopy, Fourier Transform Infrared; Spheroids, Cellular; Static Electricity; Zinc Finger Protein GLI1

Aberrant Hedgehog/GLI signaling has been implicated in a diverse spectrum of human cancers, but its role in lung adenocarcinoma (LAC) is still under debate. We show that the downstream effector of the Hedgehog pathway, GLI1, is expressed in 76% of LACs, but in roughly half of these tumors, the canonical pathway activator, Smoothened, is expressed at low levels, possibly owing to epigenetic silencing. In LAC cells including the cancer stem cell compartment, we show that GLI1 is activated noncanonically by MAPK/ERK signaling. Different mechanisms can trigger the MAPK/ERK/GLI1 cascade including KRAS mutation and stimulation of NRP2 by VEGF produced by the cancer cells themselves in an autocrine loop or by stromal cells as paracrine cross talk. Suppression of GLI1, by silencing or drug-mediated, inhibits LAC cells proliferation, attenuates their stemness and increases their susceptibility to apoptosis in vitro and in vivo. These findings provide insight into the growth of LACs and point to GLI1 as a downstream effector for oncogenic pathways. Thus, strategies involving direct inhibition of GLI1 may be useful in the treatment of LACs.

Topics: Adenocarcinoma; Animals; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Female; Humans; Lung Neoplasms; Mice; Mice, SCID; Mitogen-Activated Protein Kinase Kinases; Neoplastic Stem Cells; Neuropilin-2; Proto-Oncogene Proteins p21(ras); Pyridines; Pyrimidines; RNA Interference; RNA, Small Interfering; Xenograft Model Antitumor Assays; Zinc Finger Protein GLI1

The Hedgehog pathway plays an important role in the pathogenesis of several tumor types, including esophageal cancer. In our study, we show an expression of the ligand Indian hedgehog (Ihh) and its downstream mediator Gli-1 in primary resected adenocarcinoma tissue by immunohistochemistry and quantitative PCR in fifty percent of the cases, while matching healthy esophagus mucosa was negative for both proteins. Moreover, a functionally important regulation of Gli-1 by ErbB2-PI3K-mTORC signaling as well as a Gli-1-dependent regulation of Ihh in the ErbB2 amplified esophageal adenocarcinoma cell line OE19 was observed. Treatment of OE19 cells with the Her2 antibody trastuzumab, the PI3K-mTORC1 inhibitor NVP BEZ235 (BEZ235) or the knockdown of Akt1 resulted in a downregulation of Gli-1 and Ihh as well as in a reduction of viable OE19 cells in vitro. Interestingly, the Hedgehog receptor Smo, which acts upstream of Gli-1, was not expressed in OE19 cells and in the majority of primary human esophageal adenocarcinoma, suggesting a non-canonical upregulation of Gli-1 expression by the ErbB2-PI3K axis. To translate our findings into a therapeutic concept, we targeted ErbB2-PI3K-mTORC1 by trastuzumab and BEZ235, combining both compounds with the Gli-1/2 inhibitor GANT61. The triple combination led to significantly stronger reduction of tumor cell viability than cisplatinum or each biological alone. Therefore, concomitant blockage of the ErbB2-PI3K pathway and the Hedgehog downstream mediator Gli-1 may provide a new therapeutic strategy for esophageal cancer.

Topics: Adenocarcinoma; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Cell Survival; Down-Regulation; Esophageal Neoplasms; Esophagus; Hedgehog Proteins; HEK293 Cells; Humans; Imidazoles; Mechanistic Target of Rapamycin Complex 1; Multiprotein Complexes; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Pyridines; Pyrimidines; Quinolines; Receptor, ErbB-2; RNA Interference; RNA, Small Interfering; Signal Transduction; TOR Serine-Threonine Kinases; Transcription Factors; Trastuzumab; Tumor Cells, Cultured; Zinc Finger Protein GLI1

The HH signaling pathway is a 'core' signal transduction pathway in pancreatic cancer that promotes the tumorigenesis of pancreatic cancers via enhancing cell proliferation, increasing invasion and metastasis and protecting against apoptosis. In the present study, we found that HH signaling regulates autophagy in pancreatic cancer cells. Activation of HH signaling inhibits autophagy, while inhibition of the HH pathway induces autophagy. Although the role of autophagy in cell survival and apoptosis may depend on tumor type and the microenvironment, our data clearly demonstrated that GANT61-induced autophagy contributed to reduced viability and increased apoptosis in pancreatic cancer cells both in vivo and in vitro, and these effects were reversed by the autophagy inhibitor, 3-MA. We propose that HH signaling by regulating autophagy plays an important role in determining the cellular response to HH-targeted therapy in pancreatic cancer and further investigation of the interaction between autophagy and HH signaling is particularly important.

Topics: Adenocarcinoma; Animals; Apoptosis; Autophagy; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cell Transformation, Neoplastic; Female; Hedgehog Proteins; Humans; Kruppel-Like Transcription Factors; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Invasiveness; Neoplasm Metastasis; Nuclear Proteins; Pancreatic Ducts; Pancreatic Neoplasms; Pyridines; Pyrimidines; Signal Transduction; Transcription Factors; Xenograft Model Antitumor Assays; Zinc Finger Protein GLI1; Zinc Finger Protein Gli2