bromochloroacetic-acid and Hypoxia

Circulating tumour cells (CTCs) are a rare cell subpopulation regulated by the tumour microenvironment. In hypoxic conditions, CTCs are able to invade the lymphatic and circulatory systems leading to metastasis at distant sites.. To mimic in vivo oxygen variations and effects on CTCs, we have cultured five non-small cell lung cancer (NSCLC) cell lines under normoxic and hypoxic conditions, followed by a pulse of reoxygenation for 4 h.. Proliferation, spheroid-formation and colony formation ability under varying O. Our data suggest that when investigating CTCs as a prognostic biomarker in NSCLC, it is also essential to take into consideration EMT status to obtain a comprehensive overview of CTCs in circulation.

Topics: Biomarkers; Biomarkers, Tumor; Carcinoma, Non-Small-Cell Lung; Cell Line; Cell Line, Tumor; Epithelial-Mesenchymal Transition; ErbB Receptors; Humans; Hypoxia; Keratins; Lung Neoplasms; Neoplastic Cells, Circulating; Oxygen; RNA, Messenger; Tumor Microenvironment; Vimentin

Ameloblastoma is a locally aggressive odontogenic tumor. Etiopathogenesis and locally aggressive growth properties of ameloblastoma can be attributed to a hypoxic microenvironment conducive to tumor cell survival. Epithelial-derived follicular ameloblastoma cells (EP-AMCs) display enhanced basal autophagy, but the interplay of hypoxia and autophagy in EP-AMCs survival and ameloblastoma recurrence is unclear. We evaluated differential expression of autophagic markers in primary and recurrent ameloblastomas and hypothesized that hypoxia-induced autophagy supports EP-AMC survival. Primary and recurrent ameloblastomas were comparatively assessed for expression levels of pan-cytokeratin, Vimentin, and autophagic markers SQSTM1/p62, LC3, and pS6. EP-AMCs compared with human odontoma-derived cells (HODCs) were subjected to severe hypoxia to determine the interplay of hypoxia and autophagic process in posthypoxia survival. Pan-cytokeratin and SQSTM1/p62 were expressed by both primary and recurrent ameloblastoma epithelial cells while the ameloblastoma connective tissues displayed weak reactivity to vimentin. Under hypoxia, EP-AMC expression levels of hypoxia-inducible factor (HIF)-1α, p62, and LC3 were increased while pS6 was decreased posthypoxia. The combined decrease in pS6 and enhanced LC3 in EP-AMCs under hypoxia indicate that EP-AMCs re-establish basal autophagy under hypoxia. Taken together, these suggest a possible role of LC3-associated phagocytosis (LAP) in ameloblastoma cell survival.

Topics: Ameloblastoma; Autophagy; Cell Hypoxia; Cell Line, Tumor; Epithelial Cells; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Keratins; Sequestosome-1 Protein; Tumor Microenvironment; Vimentin

Topics: Hidradenitis Suppurativa; Humans; Hypoxia; Hypoxia-Inducible Factor 1; Inflammation; Keratinocytes; Keratins

Invasion is a hallmark of malignancy. The aim of this study was to develop an in vitro model that can be used for experimental studies of cancer cell invasion. The organotypic oral cancer model was constructed by growing oral squamous cell carcinoma (OSCC) cells on a collagen matrix in which normal human fibroblasts were incorporated. Immunohistochemical staining of the model showed that the expression of invasion-related molecules such as phosphorylated extracellular signal-regulated kinases 1 and 2 (p-ERK1/2), cyclooxygenase-2 (COX-2), p75(NTR), and hepatocyte growth factor receptor (Met) was similar to that seen in OSCC. Treatment of the model with cobalt chloride (CoCl(2)) to mimic hypoxic conditions increased cancer cell invasion, defined as the appearance of cancer cell islands protruding into the matrix. Models treated with CoCl(2) showed increased expression of p75(NTR) and laminin-5 in the cancer cells, and a more pronounced fragmentation of collagen IV in the basal membrane area, in contrast to models that were left untreated. The results indicate that the present model is well suited for studies on cancer cell invasion in the matrix and that the addition of CoCl(2) on day 3 of the experiment is indicated because it markedly increases the invasion and improves the model.

Topics: Antigens, CD; Carcinoma, Squamous Cell; Cell Culture Techniques; Cells, Cultured; Cobalt; Collagen; Collagen Type IV; Culture Media; Cyclooxygenase 2; Fibroblasts; Humans; Hypoxia; Keratins; Laminin; Male; Middle Aged; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Neoplasm Invasiveness; Nerve Tissue Proteins; Proto-Oncogene Proteins c-met; Receptors, Growth Factor; Receptors, Nerve Growth Factor; Tongue Neoplasms; Young Adult

Phenotypically and functionally different types of microvascular endothelial cells (MVECs) derived from the developing corpus luteum were isolated and characterized by our group. We investigated whether these cytokeratin-positive (CK+) and cytokeratin-negative (CK-) MVECs differed in the expression of angiogenic factors and their regulation under hypoxia. Using quantitative RT-PCR, VEGF and its receptors, Flk-1 and Flt-1, were detected in CK- MVECs. The mRNA expression of Flk-1 mRNA was 100 times as high as that of Flt-1 mRNA. CK+ MVECs expressed VEGF and Flt-1 mRNA, but were devoid of Flk-1 transcripts. No Ang-1 mRNA was demonstrated in either cell type, and Ang-2 mRNA was found only in CK- MVECs. Tie-2 mRNA was detected in both MVEC types, but levels were 150 times as high in CK- MVECs as in CK+ MVECs. mRNA of hypoxia-inducible factors Hif-1alpha and Hif-1beta was expressed in both MVEC types. After hypoxia, neither VEGF, nor Flk-1, nor Tie-2 mRNA expression was altered in either MVEC type. Flt-1 expression and Ang-2 mRNA expression were significantly increased at about 2.5-fold (P < 0.05) in CK- MVECs, but not in CK+ MVECs. Our study demonstrates the varying expression and regulation of angiogenesis-related factors and receptors in phenotypically different MVEC types.

Topics: Angiopoietin-1; Angiopoietin-2; Animals; Aryl Hydrocarbon Receptor Nuclear Translocator; Binding, Competitive; Blotting, Western; Cattle; Cells, Cultured; Cloning, Molecular; Corpus Luteum; DNA-Binding Proteins; DNA, Complementary; Endothelium, Vascular; Female; fms-Like Tyrosine Kinase 3; Humans; Hypoxia; Keratins; Membrane Glycoproteins; Neovascularization, Pathologic; Phenotype; Phosphorylation; Precipitin Tests; Protein Biosynthesis; Proto-Oncogene Proteins; Receptor Protein-Tyrosine Kinases; Receptor, TIE-2; Receptors, Aryl Hydrocarbon; Reverse Transcriptase Polymerase Chain Reaction; RNA; RNA, Messenger; Temperature; Transcription Factors; Tyrosine; Vascular Endothelial Growth Factor Receptor-1

During normal human pregnancy a subpopulation of fetal cytotrophoblast stem cells differentiate and invade the uterus and its arterioles. In the pregnancy disease preeclampsia, cytotrophoblast differentiation is abnormal and invasion is shallow. Thus, the placenta is relatively hypoxic. We investigated whether lowering oxygen tension affects cytotrophoblast differentiation and invasion. Previously we showed that when early gestation cytotrophoblast stem cells are cultured under standard conditions (20% O2) they differentiate/invade, replicating many aspects of the in vivo process. Specifically, the cells proliferate at a low rate and rapidly invade extracellular matrix (ECM) substrates, a phenomenon that requires switching their repertoire of integrin cell-ECM receptors, which are stage-specific antigens that mark specific transitions in the differentiation process. In this study we found that lowering oxygen tension to 2% did not change many of the cells' basic processes. However, there was a marked increase in their incorporation of [3H]thymidine and 5-bromo-2'-deoxyuridine (BrdU). Moreover, they failed to invade ECM substrates, due at least in part to their inability to completely switch their integrin repertoire. These changes mimic many of the alterations in cytotrophoblast differentiation/invasion that occur in preeclampsia, suggesting that oxygen tension plays an important role in regulating these processes in vivo.

Topics: Cell Adhesion; Cells, Cultured; DNA; Female; Humans; Hypoxia; Integrins; Keratins; Pre-Eclampsia; Pregnancy; Trophoblasts