ERG

MIM.165080

AGCOH.CG126

Expression in tumors

 vascular tumors

• ERG transcription factor is constitutively expressed in endothelial cells.
• Because benign and malignant vascular endothelia retain the ERG expression, ERG is considered a useful marker for angiosarcomas and related tumors.

 ERG is expressed in a subset of prostate carcinomas

• ERG expression in intraductal carcinoma of the prostate (24406865)

 ERG is expressed in Ewing sarcomas due to ERG-involved translocations.

 ERG expression is fairly common in epithelioid sarcoma and should be recognized as a diagnostic pitfall in the differential diagnosis of epithelioid sarcoma and epithelioid angiosarcoma. General lack of endothelial cell-specific markers in epithelioid sarcoma helps in this distinction. (23774169)

Fusion genes

ERG (21q22.3) has been associated with different fusion partners: FUS, EWSR1, ELF4.

 ERG-EWSR1 in

• ES-PNET tumors (Ewing sarcoma and pPNET)

 ERG-FUS fusion gene by t(16;21)(p11;q22) (16p11 and 21q22) in

• de novo acute non lymphocytic leukemia (ANLL)
• ES/PNET tumors (Ewing sarcoma and pPNET)

 ELF4-ERG fusion gene in acute myeloid leukemia (16303180)

• ELF4 at Xq25-26
• ERG at 21q22

 TMPRSS2/ERG fusion gene in prostate cancer (prostatic adenocarcinomas)

• The presence of ERG rearrangements in nearly half of the prostatic small cell carcinomas is a similar rate of rearrangement to that found in prostatic acinar carcinomas. (21336263)
• The high concordance rate of ERG rearrangement between the small cell and acinar components in a given patient supports a common origin for these two subtypes of prostate cancer. (21336263)

 Absence of ERG rearrangement in bladder or lung small cell carcinomas.

• It highlights the utility of detecting ERG rearrangement in small cell carcinomas of unknown primary for establishing prostatic origin. (21336263)

ERG amplification

 ERG amplification by amp(21)(q22.3) in acute myeloid leukemia (AML)

Cytogenetics

 t(X;21)(q25-26;q22) causing ELF4-ERG fusion gene (16303180)

References

 ERG Expression in Epithelioid Sarcoma: A Diagnostic Pitfall. Miettinen M, Wang Z, Sarlomo-Rikala M, Abdullaev Z, Pack SD, Fetsch JF. Am J Surg Pathol. 2013 Jun 14. PMID: 23774169

 ERG gene rearrangements are common in prostatic small cell carcinomas. Lotan TL, Gupta NS, Wang W, Toubaji A, Haffner MC, Chaux A, Hicks JL, Meeker AK, Bieberich CJ, De Marzo AM, Epstein JI, Netto GJ. Mod Pathol. 2011 Feb 18. PMID: 21336263

 Moore SD, Offor O, Ferry JA, Amrein PC, Morton CC, Dal Cin P. ELF4 is fused to ERG in a case of acute myeloid leukemia with a t(X;21)(q25-26;q22). Leuk Res. 2006 Aug;30(8):1037-42. PMID: 16303180