MN1 and glioblastoma: Western-blotting (Figure 3A) indicated that proNGF was expressed in all analyzed human GBM cell lines, including two standard GBM cell lines (U87MG and A172) and nine patient-derived GBM cell lines (BAH1, HW1, SB2b, RKI1, SJH1, WK1, PB1, RN1 and MN1).