POLR1A and cancer: Indeed, 2 subgroups of anti-CENPA can explain variable clinical manifestations in an ACA-positive subset.87 Subgrouping among patients with SSc positive for anti-RPC155 antibodies (RNAP III large subunit, 155 kDa) revealed that anti-RPA194 was associated with a lower cancer risk and less severe GI disease, while anti-RNAP I/II/III was associated with SRC.75 Therefore, different autoantibody combinations have utility as tools for organ involvement and cancer risk stratification in SSc.