Table 1 STAT3 isoforms

STAT3α

92

Full length

Typical STAT3 function

[47]

STAT3β

83

C-terminal truncated form (missing Ser727)

Greater DNA binding activity; Distinct regulatory and transcriptional functions; Suppressive effect on STAT3

[51]

STAT3γ

72

C-terminal truncated form (missing Ser727and Tyr705)

Activated in the terminal stage of granulocytic differentiation

[48]

STAT3δ

64

C-terminal truncated form (missing Ser727 and Tyr705)

Activated in the early stage of granulocytic differentiation

[48]