ABSTRACT
To investigate the effects of normal human bone marrow fibroblastoid stromal cell lines HFCL on the proliferation of multiple myeloma cell lines RPMI8226, the co-culture system of RPMI8226 with HFCL was established, the adhesion ratio was determined by MTT colorimetric assay, growth curves were determined by trypan blue exclusion, the mitotic index (MI) of RPMI8226 cell was observed by Wright-Giemsa staining. Flow cytometry and Western blot were used to study the changes of cell cycle and expression of proliferating cell nuclear antigen (PCNA), respectively. The results showed that in co-culture the adhesion ratio of RPMI8226 after 1 hour was 29.4%; the proliferation of RPMI8226 cell line in direct contact with HFCL cell line was inhibited as compared with RPMI8226 in suspension. No obvious changes were observed in RPMI8226 cell separated by transwell inserts. The percentage of G(1) phase cells of RPMI8226 cell line in direct contact with HFCL was higher than that of RPMI8226 in suspension, and the percentage of S phase cells was lower. Moreover, the MI of RPMI8226 cell line in suspension was higher than that of RPMI8226 cell line in direct contact with HFCL cell. The expression of PCNA in RPMI8226 cell line in suspension was higher than that of RPMI8226 cell in direct contact with HFCL cell. It is concluded that the normal human bone marrow fibroblastoid stromal cell HFCL inhibits the proliferation and progression of cell cycle of multiple myeloma cell line, RPMI8226.