title: Studies on the expression patterns of class I PI3K catalytic subunits and its prognostic significance in colorectal cancer.
abstract: The phosphatidylinositol 3-kinase/AKT (PI3K/AKT) pathway plays a critical role in human cancer. We determined the expression patterns of class I PI3K catalytic subunits and evaluated their importance in the development or progression of colorectal cancer (CRC). For this purpose, expression of class I PI3K isoforms was evaluated in 82 primary CRC and paired non-cancerous mucosa samples by qRT-PCR. P-AKT-Ser473 and P-AKT-Thr308 expression were measured by western blot. We found that, compared with paired non-cancerous mucosa samples, mRNA expression of p110α and p110β in CRCs was significantly increased to 2.02-fold (95% confidence interval [CI] 1.25-3.28 fold) and 1.76-fold (95% CI 1.19-2.60 fold), respectively; while slight differences were found regarding the expression of p110δ (0.57-fold; 95% CI 0.31-1.07 fold) and p110γ (0.97-fold; 95% CI 0.50-1.88 fold). Increased p110α and p110β expression correlated with primary tumor size, regional lymph node metastases, and AJCC stage. Increased p110β expression also correlated with distant metastasis. P-AKT-Thr308 and P-AKT-Ser473 expression showed significant direct correlations with p110α and p110β mRNA expression. Besides, CRC patients with p110β mRNA overexpression had a worse disease-free survival after radical surgery compared with those with normal or decreased levels (P = 0.043). It was, therefore, concluded that the altered p110α and p110β expression might contribute to the CRC development or progression.
authors: Department of Colorectal Surgery, The Affiliated 3rd Hospital, Harbin Medical University, Harbin, People's Republic of China.
authors: Binbin
authors: B
authors: Cui
authors: Ji
authors: J
authors: Tao
authors: Yanmei
authors: Y
authors: Yang
mesh_terms: D020134:Catalytic Domain; D058543:Class Ia Phosphatidylinositol 3-Kinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D020033:Protein Isoforms; D012333:RNA, Messenger; D058543:Class Ia Phosphatidylinositol 3-Kinase