salinomycin and Squamous-Cell-Carcinoma-of-Head-and-Neck

Long non-coding RNAs (lncRNAs) contribute to the initiation and progression of various tumors, including head and neck squamous carcinoma (HNSCC), which is a common malignancy with high morbidity and low survival rate. However, the mechanism of lncRNAs in HNSCC tumorigenesis remains largely unexplored. In this work, we identified a novel lncRNA AC104041.1 which is highly upregulated and correlated with poor survival in HNSCC patients. Moreover, AC104041.1 overexpression significantly promoted tumor growth and metastasis of HNSCC in vitro and in vivo. Mechanistically, AC104041.1 mainly located in the cytoplasm and could function as ceRNA (competing endogenous RNA) for miR-6817-3p, thereby stabilized Wnt2B, and consequently inducing β-catenin nuclear translocation and activation. Moreover, we demonstrate that salinomycin, which as a highly effective antibiotic in the elimination of cancer stem cells through the Wnt/β-catenin signaling, could enhance the inhibition of tumor growth by antisense oligonucleotides (ASO) targeting AC104041.1 in HNSCC cells and PDXs (patient-derived xenograft) model. Thus, our data provide preclinical evidence to support a novel strategy of ASOs targeting AC104041.1 in combination with salinomycin and may as a beneficial treatment approach for HNSCC.

Topics: Animals; Antineoplastic Agents; Carcinogenesis; Cell Line, Tumor; Cell Movement; Cell Proliferation; Female; Gene Expression Regulation, Neoplastic; Glycoproteins; Head and Neck Neoplasms; Humans; Mice, Inbred BALB C; Mice, Nude; MicroRNAs; Neoplasm Metastasis; Oligonucleotides, Antisense; Oncogenes; Pyrans; RNA, Long Noncoding; Squamous Cell Carcinoma of Head and Neck; Survival Analysis; Wnt Proteins; Wnt Signaling Pathway

The antibiotic drug salinomycin has been reported to mediate cancer cell-specific cytotoxicity, especially regarding cancer stem cells. Since salinomycin has also been reported to arrest cancer cells in the G2 phase, it may have possible radiosensitizing effects. Radiotherapy is a common therapeutic strategy for head and neck squamous cell carcinoma (HNSCC). The aim of the present study was to evaluate a possible influence of salinomycin on the radiosensitivity of the HNSCC cell line HLaC-78 in vitro. HLaC-78 cells were incubated with 5 µM salinomycin or control medium for 24 h and then received 5-Gy irradiation. Subsequently, analysis of cell viability, apoptosis, necrosis and motility through an MTT and a colony formation assay, as well as an Annexin V/propidium-iodide test, a consecutive cell count for four days and a scratch assay were conducted. Additionally, interleukin-8 secretion was assessed using ELISA, due to its role in tumor progression and angiogenesis. Combined treatment with salinomycin and radiation revealed a significantly higher reduction of tumor cell viability, proliferation, motility and secretory capacity compared to cells receiving only one of the treatments alone. Therefore, it is postulated that radiation and salinomycin are an effective combination therapy against HNSCC, a hypothesis which warrants further investigation in cell lines, as well as in an animal model.

Topics: Apoptosis; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Combined Modality Therapy; Head and Neck Neoplasms; Humans; Neoplastic Stem Cells; Pyrans; Radiation Tolerance; Squamous Cell Carcinoma of Head and Neck

To target both head and neck squamous cell carcinoma (HNSCC) cells and cancer stem cells (CSCs) by salinomycin-loaded DSPE-PEG-MTX (synthesized using DSPE-PEG2000-NH2 and methotrexate) nanomicelles (M-SAL-MTX).. The characterization, antitumor activity and mechanism of M-SAL-MTX were evaluated.. M-SAL-MTX showed enhanced inhibitory effect toward both HNSCC CSCs and non-CSCs compared with a single treatment of methotrexate and salinomycin. In nude mice-bearing HNSCC xenografts, M-SAL-MTX suppressed tumor growth more effectively than other controls including combination of methotrexate and salinomycin. Therefore, M-SAL-MTX may provide a strategy for treating HNSCC by targeting both HNSCC CSCs and HNSCC cells.

Topics: Animals; Anti-Bacterial Agents; Antimetabolites, Antineoplastic; Carcinoma, Squamous Cell; Cell Line, Tumor; Drug Carriers; Drug Delivery Systems; Head and Neck Neoplasms; Humans; Male; Methotrexate; Mice, Inbred BALB C; Mice, Nude; Micelles; Neoplastic Stem Cells; Phosphatidylethanolamines; Polyethylene Glycols; Pyrans; Squamous Cell Carcinoma of Head and Neck

Cancer stem cells (CSC) are believed to play a crucial role in cancer recurrence due to their resistance to conventional chemotherapy and capacity for self-renewal. Recent studies have reported that salinomycin, a livestock antibiotic, selectively targets breast cancer stem cells 100-fold more effectively than paclitaxel. In our study we sought to determine the effects of salinomycin on head and neck squamous cell carcinoma (HNSCC) stem cells.. MTS and TUNEL assays were used to study cell proliferation and apoptosis as a function of salinomycin exposure in JLO-1, a putative HNSCC stem cell culture. MTS and trypan blue dye exclusion assays were performed to investigate potential drug interactions between salinomycin and cisplatin or paclitaxel. Stem cell-like phenotype was measured by mRNA expression of stem cell markers, sphere-forming capacity, and matrigel invasion assays. Immunoblotting was also used to determine expression of epithelial-mesenchymal transition (EMT) markers and Akt phosphorylation. Arrays by Illumina, Inc. were used to profile microRNA expression as a function of salinomycin dose.. In putative HNSCC stem cells, salinomycin was found to significantly inhibit cell viability, induce a 71.5% increase in levels of apoptosis, elevate the Bax/Bcl-2 ratio, and work synergistically with cisplatin and paclitaxel in inducing cell death. It was observed that salinomycin significantly inhibited sphere forming-capability and repressed the expression of CD44 and BMI-1 by 3.2-fold and 6.2-fold, respectively. Furthermore, salinomycin reduced invasion of HNSCC stem cells by 2.1 fold. Contrary to expectations, salinomycin induced the expression of EMT markers Snail, vimentin, and Zeb-1, decreased expression of E-cadherin, and also induced phosphorylation of Akt and its downstream targets GSK3-β and mTOR.. These results demonstrate that in HNSCC cancer stem cells, salinomycin can cause cell death and decrease stem cell properties despite activation of both EMT and Akt.

Topics: Apoptosis; bcl-2-Associated X Protein; Carcinoma, Squamous Cell; Cell Death; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cisplatin; Drug Interactions; Enzyme Activation; Epithelial-Mesenchymal Transition; Head and Neck Neoplasms; Humans; Hyaluronan Receptors; MicroRNAs; Mitogen-Activated Protein Kinase 7; Neoplastic Stem Cells; Paclitaxel; Phosphorylation; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Pyrans; RNA, Messenger; Squamous Cell Carcinoma of Head and Neck