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(2011). https://pubmed.ncbi.nlm.nih.gov/21346252/ DOI: 10.1182/blood-2010-09-307637","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cervical carcinoma cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"6076c706-54c5-534d-8658-908fb5160149","evidence_kind":"source_excerpt","locator":"Lines 1173-1185","start_line":1173,"end_line":1185,"excerpt":"### c-reg-hela-hypoxia-preserved\nHeLa cells maintained in serum-free, ascorbate-free defined medium retained hypoxic HIF-1 alpha stabilization and HIF-dependent reporter activation relative to cells supplied with 50 µM ascorbate.\nCondition category: nutrient_deficiency\nnutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Removing vitamin C from this adapted cancer-cell culture did not switch off its measured low-oxygen response.\norganism: Homo sapiens\ntissue_or_cell_type: Cervical carcinoma cells\nexperimental_model: HeLa adapted to serum-free Ham F-12; HIF immunoblot and luciferase reporter\nlimitations: Cell-culture omission, not a controlled human dietary deficiency; residual adaptive reductant pathways were not eliminated.\nexposure: 0 versus 50 µM ascorbate; 0.2% versus 21% oxygen for 6-h protein assay, graded oxygen for 24-h reporter assay.\ncross_nutrient: false\nevidence_location: Figure 1B–C\n[c-reg-nytko] Vitamin C is dispensable for oxygen sensing in vivo. 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