2.4. Bone Formation-Related Markers Content by Reverse Transcription-Polymerase Chain Reaction (RT-PCR)
After differentiation for 10 days of SaOS-2 cells, the TRIzol method was used to isolate the RNA from cells. RNAs were treated with a complementary DNA kit (Maxime RT premix kit; Invitrogen, Carlsbad, CA, USA) and verified for subsequent reverse transcription in order to evaluate the expression of the following selected genes of interest, respectively: GAPDH, 5′-GGCATGGACTGTGGTCATGA-3′ and 5′-TTCACCACCATGGAGAAGGC-3′; COL, 5′-TAGGCCATTGTGTATGCAGC-3′ and 5′-ACATGTTCAGCTTTGTGGACC-3′; OCN, 5′-AGCTCAACCCCAATTGTGAC-3′ and 5′-AGCTGTGCCGTCCATACTTT-3′; BSP-1, 5′-GAGCCAGGACTGCCGAAAGGAA-3′ and 5′-CCGTTGTCTCCTCCGCTGCTGC-3′; BMP-2, 5′-GCGGTGGACTGCACAGGGAC-3′ and 5′-CTACCCTTCCCCGTGGGGGA-3′; ALP, 5′-TGGAGCTTCAGAAGCTCAACACCA-3′ and 5′-ATCTCGTTGTCTGAGTACCAGTCC-3′.