Colorectal cancers differ in respect of PARP-1 protein expression

Violetta Sulzyc-Bielicka (1) , Pawel Domagala (2) , Jolanta Hybiak (2) , Anna Majewicz-Broda (2) , Krzysztof Safranow (3) , Wenancjusz Domagala (2)

1 Department of Clinical Oncology
2 Department of Pathology
3 Department of Biochemistry and Medical Chemistry

Recent findings raise the possibility of PARP inhibitor therapy in colorectal cancers (CRCs). However, the extent of PARP-1 protein expression in clinical specimens of CRC is not known. Using immunohistochemistry we assessed PARP-1 protein expression in tissue microarrays of 151 CRCs and its association with the patient's age, sex, Astler-Coller stage, grade and site of the tumor. High PARP nuclear immunoreactivity was found in 68.2% (103/151) of all cases. In turn, 31.8% (48/151) of tumors showed low PARP expression, including 9 (6%) PARP-1 negative CRCs. There was a significant association of PARP-1 expression with the site of CRC and Astler-Coller stage. A high PARP expression was noted in 79.1% of colon vs. 53.9% of rectal tumors (p = 0.001). The mean PARP-1 score was 1.27 times higher in colon vs. rectal cancers (p = 0.009) and it was higher in stage B2 vs. stage C of CRCs (p = 0.018). In conclusion, the level of PARP-1 protein nuclear expression is associated with the tumor site and heterogeneous across clinical specimens of CRC, with the majority of CRCs expressing a high level but minority - low or no PARP-1 expression. These findings may have a clinical significance because the assessment of PARP-1 expression in tumor samples may improve selection of patients with CRC for PARP inhibitor therapy.

Domaines: Médecine humaine et pathologie

Violetta Sulzyc-Bielicka, Pawel Domagala, Jolanta Hybiak, Anna Majewicz-Broda, Krzysztof Safranow, et al.. Colorectal cancers differ in respect of PARP-1 protein expression. Polish journal of pathology : official journal of the Polish Society of Pathologists, 2012, 63 (2), pp.87-92. ⟨hal-00721624⟩