Oct4 expression in gastric carcinoma: association with tumor proliferation, angiogenesis and survival.

BACKGROUND: Octamer-binding transcription factor 4 (Oct4) is a transcription factor that has an important role in stem cell differentiation and self-renewal. Oct4 has also been implicated in tumorigenicity of different cancers. This study aimed to analyze Oct4 expression in gastric carcinoma (GC) and to evaluate the relation between Oct4 expression and clinicopathologic parameters, tumor proliferation, and angiogenesis in addition to patient survival. RESULTS: Oct4 mRNA was detected by quantitative reverse transcription PCR (qRT-PCR) in 45 GC specimens and adjacent non-cancerous tissues. We found a significant difference in Oct4 mRNA relative expression levels in GC tissue compared with adjacent non-cancerous tissues (p < 0.001). Furthermore, immunohistochemistry (IHC) was performed to study the Oct4 expression in GC cases. High Oct4 immunostaining was detected in 62.2% of GC specimens. High Oct4 expression both by mRNA relative quantitation and IHC were significantly related to poorly differentiated tumors, nodal metastasis, and stage III tumors. Moreover, high Oct4 IHC expression was also associated with cases positive for Ki-67 and VEGF expressions (p < 0.001 and 0.021, respectively). Oct4 expression identified by both mRNA relative quantitation and IHC was significantly related (p < 0.001). As regards patient survival, high Oct4 expression was significantly related to poor overall survival (OS) and disease-free survival (DFS) (p = 0.029 and 0.031, respectively). CONCLUSION: Oct4 plays a valuable role in the progression and prognosis of GC. High Oct4 expression is associated with high tumor grade, nodal metastasis, stage III tumors, and poor OS and DFS. High Oct4 is also significantly associated with Ki-67 and VGEF expression, thus enhancing tumor proliferation and angiogenesis.

Fatty acid synthase/oxidized low-density lipoprotein as metabolic oncogenes linking obesity to colon cancer via NF-kappa B in Egyptians.

Obesity is a major health problem which heightens the risk of several chronic illnesses including cancer development particularly colon cancer. The underlying pathophysiology of obesity associated colon cancer remains to be elucidated. The purpose of this current study was to determine fatty acid synthase (FASN) activity/expression, oxidized low-density lipoprotein (ox-LDL) level and redox status under the context of anthropometric measurements and lipid profile to find their potential role as interacting biomarkers relating obesity to colon cancer initiation and progression via nuclear factor kappa-B (NF-κB) signaling. This study was conducted upon Egyptian individuals; 30 obese subjects with colon cancer, 11 nonobese and 11 obese subjects without colon cancer. FASN gene expression, NF-κB immunoreactivity, and serum ox-LDL level were estimated by real-time PCR, immunohistochemistry and immunoassay, respectively. FASN activity, glycemic status, obesity, and oxidative stress indices were also assessed. It was found that FASN expression and activity were statistically increased in obese with colon cancer (P=0.021 and 0.018, respectively), with statistically significant increase in patients with advanced grading. Moreover, NF-κB immunoreactivity and serum ox-LDL level were significantly increased in obese colon cancer patients with significantly higher levels in those with advanced grading (all P<0.05). Dyslipidemia, insulin resistance, and oxidative stress indices were worsened in obese patients with colon cancer. These results revealed that FASN and ox-LDL as well as oxidative stress may increase the risk of obesity related colon cancer, particularly via NF-κB signaling and could be used as potential predictive and prognostic biomarkers for obesity complicated with colon cancer.