Characterization of a human osteoblastic osteosarcoma cell line (SAOS-2) with high bone alkaline phosphatase activity

Abstract

We characterized the alkaline phosphatase activity of the human osteogenic sarcoma cell line, SAOS-2, and studied the regulation of this enzyme and 3',5'-cyclic adenosine monophosphate levels by 1,25-dihydroxyvitamin D3 and triamcinolone acetonide. We report that the basal alkaline phosphatase activity of SAOS-2 cells was 100-1000 times greater than that of other established human osteogenic sarcoma cell lines. The enzymatic activity was thermolabile, could be inhibited by levamisole and L-homoarginine, but not by L-phenylalanine, and was immunoprecipitable with anti-bone/liver/kidney, but not with anti-placental antibody, confirming that it is the tissue-unspecific or bone/liver/kidney isoenzyme. However, in contrast to other established human osteosarcoma cell lines (TE-85, SAOS-1), in which alkaline phosphatase activity is stimulated several-fold by the steroid hormones 1,25-dihydroxyvitamin D3 and hydrocortisone, the alkaline phosphatase activity of SAOS-2 cells was not affected by 1,25-dihydroxyvitamin D3 treatment despite the presence of classical receptors for this hormone. Furthermore, administration of the potent glucocorticoid analogue, triamcinolone acetonide, induced only a modest increase in activity. The SAOS-2 cell line expressed low basal cAMP levels (28 pmol/10(6) cells) which could be increased 25-40 times by pretreatment with parathyroid hormone. However, unlike other osteoblastic models, in which PTH-induced cAMP stimulation is modulated by 1,25-dihydroxyvitamin D3 and glucocorticoids, neither of these hormones had an effect on the PTH-stimulated cAMP levels in SAOS-2 cells. We conclude that the SAOS-2 cell line is an osteoblastic cell model which expresses high levels of tissue-unspecific alkaline phosphatase activity and exhibits limited responsiveness to two steroid hormones.(ABSTRACT TRUNCATED AT 250 WORDS)

Sandblasted-acid-etched titanium surface influences in vitro the biologicalbehavior of SaOS-2 human osteoblast-like cells

“…SaOS-2 cells represent a good in vitro model to study the interaction of cells with implant biomaterials exhibiting large analogies with immature osteoblast cells [38][39][40][41]47) compared to other immortalized cell lines. Shapira and Halabi 43) recently reported that, in contrast to primary cultured human osteoblasts that do not yield consistent results due to their tendency to lose the osteoblastic phenotype during cell culture, SaOS-2 cells showed more manageability without loss of phenotypical expression.…”

“…Several primary and transformed cell lines have been used to develop culture systems to study the interaction of cells with implant biomaterials 8,14,[17][18][19][36][37][38][39][40][41][42][43][44][45][46] . SaOS-2 is an osteoblast-like cell line, derived from a human osteosarcoma, that several studies have demonstrated to be a relevant cell model, due to its large analogies with immature osteoblast cells [38][39][40][41]47) and better manageability when compared to primary human cell Sandblasted-acid-etched titanium surface influences in vitro the biological behavior of SaOS-2 human osteoblast-like cells culture 43) .…”

“…SaOS-2 is an osteoblast-like cell line, derived from a human osteosarcoma, that several studies have demonstrated to be a relevant cell model, due to its large analogies with immature osteoblast cells [38][39][40][41]47) and better manageability when compared to primary human cell Sandblasted-acid-etched titanium surface influences in vitro the biological behavior of SaOS-2 human osteoblast-like cells culture 43) . The aim of the present study was to evaluate in vitro the biological behavior of SaOS-2 cells, cultured on two different titanium surfaces, smooth (S) and sandblastedacid-etched (SBA), by investigating cell morphology, adhesion, proliferation, expression of some bone differentiation markers and ECM components as well as the expression of specific integrin subunits.…”

Therapeutic touch affects DNA synthesis and mineralization of human osteoblasts in culture

“…Human osteoblast-like cells (SaOs-2), derived from an osteosarcoma and obtained from American Type Culture Collection (Rockville, MD), were cultured in RPMI medium with 8% FBS and 100 units/mL penicillin G and 100 mg/mL of streptomycin sulfate. 16,17 When almost confluent, HOBs and SaOs-2 cells were harvested with 0.01% trypsin and were replated at 10,000 cells/cm 2 in six-well dishes. For mineralization studies, the medium was changed after 3-4 days in culture to a-MEM supplemented with FBS and antibiotics, and 50 mg/mL of ascorbate was added daily.…”

Plasma ion implantation enabled bio-functionalization of PEEK improves osteoblastic activity

“…44 For example, SAOS-2 ALP activity has been found to be unresponsive to 1,25-dihydroxyvitamin D 3 , a steroid hormone typically capable of stimulating ALP activity in other human osteosarcoma cell lines (e.g., SAOS-1), suggesting that the enzyme is constitutively expressed at near maximum levels. 53 Improved surface chemistry and biological activity are therefore unlikely to increase SAOS-2 ALP expression, regardless of the substrate molecular environment, as observed here.…”