Elevated expression of the leukemia-associated antigen SSX2IP predicts survival in acute myeloid leukemia patients who lack detectable cytogenetic rearrangements

Greiner et al1 described a positive association between elevated leukemia-associated antigen (LAA) expression (RHAMM, G250/CA9, and PRAME) and survival in 116 acute myeloid leukemia (AML) patients by microarray. We have analyzed 312 presentation AML samples using 199 133A chips and 113 Plus2 chips and segregated AML patients based on above- and below-median levels of expression of the LAA synovial sarcoma X breakpoint 2–interacting protein (SSX2IP).2-4 Analysis of Kaplan-Meier curves showed an association between elevated SSX2IP expression and improved survival times (log-rank test, P = .05). We found that SSX2IP expression did not predict the survival of AML patients who had detectable cytogenetic abnormalities; however, it was significantly associated with improved survival rates in patients with no detectable cytogenetic rearrangements (log-rank test, n = 180; P = .007; Figure 1A). We also found a correlation between elevated SSX2IP expression and other clinical parameters that are considered to be good prognostic markers: days in remission (log-rank test, P = .03), age at diagnosis (< 60 years; t test, P = .003), and FLT3 WT (t test, P = .004).