Predictive value of different proportion of lesion HLA-G expression in colorectal cancer

Differential expression of HLA-G has been observed among cancer types and tumors from individuals with the same type of cancer; however, its clinical significance is rather limited. In this study, expression and predictive relevance of HLA-G expression in 457 primary colorectal cancer (CRC, n(colon) = 232, n(rectal) = 225) patients was investigated. Data showed 70.7% (323/457) of the CRC were HLA-G expression when the above 5% (HLA-G(Low)) was considered as positive, which wasn't associated with patient survival (p = 0.109). However, HLA-G expression above 55% (HLA-G(High)) was associated with a worse prognosis of CRC patients (p = 0.042). Furthermore, a shorter survival was found for the female (p = 0.042) and elder (p = 0.037) patients whose HLA-G expression was above HLA-G(Low) level. HLA-G expression above HLA-G(High) level showed a worse prognosis for female (p = 0.013), elder (p = 0.023), colon cancer (p = 0.016), advanced tumor burden (T(3+4), p = 0.018), regional lymph node status (N(1+2), p = 0.044), and advanced clinical stage patients (AJCC (III+IV), p = 0.037). In conclusion, our results demonstrated for the first time that combination of differential lesion HLA-G expression notably improved the value of traditional survival prediction for CRC patients.