Platelet TLT-1 expression increases with NSCLC tumor growth in mice. (A) The immunocompromised MISTRG-6 mice (humanized) were injected subcutaneously with tumor cells derived from NSCLC patients and tumor growth was monitored for 4 wk. Platelets isolated after 4 wk from NSCLC tumor–bearing or control mice were used for FC-based assays. (B and C) The representative FC histogram. Blue represents control mice, red is patient-derived xenograft (PDX) tumor (B), and the quantitation (C) of surface TLT-1–staining shows increased TLT-1 staining in mice with NSCLC tumor (n = 4 for control, n = 6 for PDX tumor mice). Statistical significance tested by Mann–Whitney test. (D) The Pearson’s correlation curve between platelet TLT-1 level (FC-based assay shown in C) and respective tumor volume in each mouse (n = 6) shows significant correlation (P < 0.05). The data represent two independent experiments. The scatter plots present values with mean ± SEM. The P value shown corresponds to the applied non-parametric two tailed Mann–Whitney test. Significant differences are indicated with asterisks (*, P < 0.05).