Fig. 7. N-terminal amino acids of PAQR11 are required to rescue PAQR11-deficient cells.

(A) A topological model of PAQR11. N5: The first five N-terminal amino acids. (B) Colonies formed in soft agar by shCTL- and shPAQR11-transfected H1299 cells. The latter were rescued with full-length (PAQR11) or N-terminally truncated (∆N5) PAQR11. (C and D) Western blot analysis of cleaved PARP1 (C) and annexin V/propidium iodide flow cytometry (D) of cells under suspension conditions. (E) Western blot analysis of FAM3C and PLAU in CM samples (CM) and cell lysates (lysates). (F) Western blot analysis of pSTAT3 and total STAT3. (G) A competing peptide that includes the first 28 N-terminal amino acids of PAQR11 (PAQR11-N) (schema) was detected by anti-GFP Western blot analysis in H1299 cells. (H and I) Western blot analysis of cleaved PARP1 (H) and annexin V/propidium iodide flow cytometry (I) of H1299 cells transfected with (PAQR11-N) or without (GFP) competing peptide under adherent or nonadherent conditions. (J) Colonies formed in soft agar by H1299 cells transfected with (PAQR11-N) or without (GFP) competing peptide. (K) Lung metastases generated in syngeneic, immunocompetent mice by 344SQ cells transfected with (PAQR11-N) or without (GFP) competing peptide. Results represent means ± SD values from a single experiment incorporating biological replicate samples (n = 3, unless otherwise indicated) and are representative of at least two independent experiments carried out on separate days. P values, two-tailed Student’s t test for two-group comparisons and one-way ANOVA test for multiple comparisons.