Expression of BDNF and its receptors in human CRC cell lines.

<p>(A): RT-PCR of BDNF, its high (TrkB) and low (p75^NTR) affinity receptors, TrkA, and TrkC from cells cultured in basal (10% FCS medium), WiDr (lane: 1), SW480 (lane: 2), SW620 (lane: 3), COLO 205 (lane: 4). GAPDH mRNA levels was used as an internal control. Positive control (lane 5) was the neuroblastoma cell line (IMR32) for BDNF, TrkB and p75^NTR; and the erythromyeloblastoid leukemia cells (K562) for TrkA and C. A representative result of at least three to five independent experiments. (B) Comparison of TrkB95 and p75^NTR on total RNA extracted from WiDr cells cultured in 10% FCS or after 24 to 72 h serum deprivation (0% FCS). TrkB95 and p75^NTR mRNA/GAPDH mRNA quantification of band intensities evaluated by densitometry are shown above lanes and expressed in arbitrary units (mean of three independent experiments). (C) Same experiment: RT-PCR of TrkA and TrkC on total RNA extracted from WiDr cells cultured under basal culture conditions (10% FCS) and after 24–72 h of serum starvation in comparison to positive control (K562) (D) Expression of pro-BDNF and BDNF, full length TrkB 145 and truncated TrkB 95 and p75^NTR proteins in CRC cell lines cultured in 10% FCS. TrkA and TrkC were not detected. Actin was used as loading protein control. WiDr (lane: 1), SW480 (lane: 2), SW620 (lane: 3), COLO 205 (lane: 4). Positive control (lane: 5) were IMR32 cells for BDNF, pro-BDNF, TrkB and p75^NTR and K562 cells or TrkA and TrkC. A representative result of at least three independent experiments.