Phosphatidylinositol 3-kinase CB association with preoperative radiotherapy response in rectal adenocarcinoma

Figure 1 Representative immunostaining of low (A) and high (B) expression of PIK3CB from pretreatment rectal cancer specimens, which respectively show low (C) and high (D) grades of tumor regression after radiotherapy. Magnification, × 100.

Figure 2 Kaplan-Meier survival curves plotted to predict overall survival in accordance. A: TGR; B: PIK3CB; C-E: Associations of DSS, LRFS and MeFS between TRG; F-H: PIK3CB immunoexpression are also illustrated. OS: Overall survival; DSS: Disease-specific survival; LRFS: Local recurrences-free survival; MeFS: Metastasis-free survival; TRG: Tumor regression grade; PIK3: Phosphatidylinositol 3-kinase.

Figure 3 Both at mRNA (A) and protein (B) levels, PIK3CB expression was significantly upregulated in all four colon cancer cells tested (HCT-116, HT29, LoVo, and LS174T) after in vitro 6-Gy irradiation for 1-12 d. In vitro clonogenic formation assay after exposure to 6-Gy ionizing radiation of HCT-116, HT-29, LoVo and LS174T colorectal cancer cells, with or without 100 μmol/L TGX221 (a PIK3CB-specific inhibitor). Each experiment was performed in triplicate and with three repeats for each group. Error bars represent ± 1 SEM. R: Radiation.