|The following article features coverage from the ESMO World Congress on Gastrointestinal Cancer 2018 meeting. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
High expression of two autophagy-related proteins were associated with prolong survival of patients with colorectal cancer (CRC) treated with chemotherapy, according to a study presented at the ESMO World Congress on Gastrointestinal Cancer.1
Though autophagy prior to tumorigenesis is considered to suppress carcinogenesis, after tumorigenesis, autophagy can promote tumor cell survival. The purpose of this study was to determine if autophagy-related proteins are associated with survival among patients with CRC.
The study included 68 patients with CRC who received chemotherapy in adjuvant setting or for metastatic disease. The autophagy-related proteins p62 and LC3B, as well as microsatellite instability, were assessed by immunohistochemistry, with scoring based on proportion of positive tumor cells and staining intensity. KRAS, NRAS, and BRAF status was determined by polymerase chain reaction. p62 expression was not associated with any baseline characteristics, but high LC3B expression was associated with KRAS mutation–positive CRC compared with disease harboring wild-type KRAS (P = .055)
Overall survival (OS) was significantly associated with high p62 expression at 24.8 months compared with 15.9 months with low expression (P = .008); high LC3B expression was similarly associated with prolonged survival compared with lower expression (24.9 vs 16.1 months; P = .007). Both p62 and LC3B remained independent prognostic factors after multivariate adjustment for tumor grade, disease stage, and mutational status.
p62 and LC3B expression were not associated with recurrence-free survival.
The authors hypothesized that elevated autophagy-related proteins correlated with prolong survival because chemotherapy may inhibit autophagy, thus resulting in an accumulation, and therefore high expression, of p62 and LC3B.
Read more of Cancer Therapy Advisor‘s coverage of the ESMO World Congress on Gastrointestinal Cancer 2018 meeting by visiting the conference page.
- Karamouzis M, Saetta A, Koustas E, et al. Autophagy (A) related proteins evaluation represents an independent survival factor of colorectal cancer (CRC) patients (pts). Ann Oncol. 2018;29 (suppl 5;abstr P-208):v58. doi: 10.1093/annonc/mdy151.207