Figure 2.

Effects of transient depletion of TS on TS activity and the proliferation of lung cancer cell lines. (A) The indicated cell lines were transfected with a nonspecific (NS) siRNA or with either of three different siRNAs specific for TS mRNA (TS-1, TS-2, and TS-3) for 48 h, after which cell lysates were prepared and subjected to immunoblot analysis with antibodies to TS and β-actin (loading control). (B) The indicated cell lines were left untreated (NT) or were transfected with nonspecific or TS-1 siRNAs for 48 h, after which cell lysates were prepared and subjected to immunoblot analysis with antibodies to TS and β-actin. (C) Cells were left untreated or were transfected with NS or TS-1 siRNAs for 72 h, after which cell lysates were prepared and assayed for TS activity. Data are expressed as a percentage of the value for untreated cells and are means±s.d. of triplicates from experiments that were repeated on at least one additional occasion with similar results. (D) Cells were left untreated or were transfected with NS or TS-1 siRNAs for 72 h, after which cell viability was assessed with the MTT assay. Data are expressed as a percentage of the value for untreated cells and are means of triplicates from experiments that were repeated on two additional occasions with similar results. (E) Cells were left untreated or were transfected with NS or TS-1 siRNAs for the indicated times, after which cell viability was assessed with the MTT assay. Data are means±s.d. of triplicates from experiments that were repeated on two additional occasions with similar results.