@entity11408 cells were normal @entity1 nasopharvngeal epithelial cells transformed by transfection with @entity1799 deoxyribonucleic acid. @entity291 pituitary extract (BPE) was one of the indispensable ingredients for in vitro culture of @entity11408 cells in a serum-free medium. Chromatographic fractionation of BPE and subsequent immunoblotting analyses identified the hemoglobin growth-stimulating factor. @entity3961 (metHb) was then synthesized, and also found to be growth stimulating. The growth-stimulating effect of metHb was abolished when @entity11408 cells were cultured in a medium that also contained @entity2104 , a molecule that binds to hemoglobin. A defined medium consisting of insulin and metHb was then developed for optimal growth of @entity11408 cells. MetHb kept under the conditions identical to those of cell culture released hemin which also enhanced the cell growth. Though all the degradation products of hemin are currently known to be physiologically significant. only ferric @entity68 derived from metHb or hemin could stimulate the growth of @entity11408 cells. Abnormal vasculature showing leaky walls and @entity548 is a common feature of @entity5 . Hemoglobin originating from extravasated red blood cells and subsequently oxidized to metHb because of the presence of activated inflammatory cells might contribute to the increased proliferation of cancerous cells.

@entity3961 is a supplement for in vitro culture of @entity1 nasopharyngeal epithelial cells transformed by XXXX DNA.

@entity1 :: ('9606', 'Species') :: ['human'] @entity3961 :: ('3048', 'Gene') :: ['Methemoglobin'] @entity548 :: ('MESH:D006470', 'Disease') :: ['hemorrhage'] @entity2104 :: ('3240', 'Gene') :: ['haptoglobin'] @entity5 :: ('MESH:D009369', 'Disease') :: ['malignant tumors'] @entity1799 :: ('333760', 'Species') :: ['human papillomavirus type 16'] @entity11408 :: ('MESH:C538339', 'Disease') :: ['NPC-N'] @entity291 :: ('9913', 'Species') :: ['Bovine'] @entity68 :: ('MESH:D007501', 'Chemical') :: ['iron']
@entity1799 :: (333760,Species) :: ['human papillomavirus type 16']
