Lymphangiogenesis in gastric cancer regulated through Akt/mTOR-VEGF-C/VEGF-D axis

Hongxia Chen; Runnian Guan; Yupeng Lei; Jianyong Chen; Qi Ge; Xiaoshen Zhang; Ruoxu Dou; Hongyuan Chen; Hao Liu; Xiaolong Qi; Xiaodong Zhou; Changyan Chen

doi:10.1186/s12885-015-1109-0

Lymphangiogenesis in gastric cancer regulated through Akt/mTOR-VEGF-C/VEGF-D axis

BMC Cancer. 2015 Mar 7:15:103. doi: 10.1186/s12885-015-1109-0.

Authors

Hongxia Chen¹, Runnian Guan², Yupeng Lei³, Jianyong Chen⁴, Qi Ge⁵, Xiaoshen Zhang⁶, Ruoxu Dou⁷, Hongyuan Chen⁸, Hao Liu⁹, Xiaolong Qi^{10

11}, Xiaodong Zhou¹², Changyan Chen^{13

14}

Affiliations

¹ Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, 17 Yongwaizheng Street, Nanchang, 330006, China. [email protected].
² Department of Gastroenterology, Kaiping Central Hospital, Kaiping, 529300, China. [email protected].
³ Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, 17 Yongwaizheng Street, Nanchang, 330006, China. [email protected].
⁴ Department of Gastroenterology, Jiangxi Provincial People's Hospital, Nanchang, 330006, China. [email protected].
⁵ Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, 17 Yongwaizheng Street, Nanchang, 330006, China. [email protected].
⁶ Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. [email protected].
⁷ Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. [email protected].
⁸ Department of Pathogen Biology and Immunology, School of Basic Course, Guangdong Pharmaceutical University, Guangzhou, 510060, China. [email protected].
⁹ Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. [email protected].
¹⁰ Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, 17 Yongwaizheng Street, Nanchang, 330006, China. [email protected].
¹¹ Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. [email protected].
¹² Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, 17 Yongwaizheng Street, Nanchang, 330006, China. [email protected].
¹³ Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, 17 Yongwaizheng Street, Nanchang, 330006, China. [email protected].
¹⁴ Center for Drug Discovery, Northeastern University, Boston, MA, 02115, USA. [email protected].

Abstract

Background: Lymphangiogenesis plays a significant role in metastasis and recurrence of gastric cancer. There is no report yet focusing on the modulation of VEGF pathway and lymphangiogenesis of gastric cancer by targeting Akt/mTOR pathway. This study aims to demonstrate the relationship between Akt/mTOR pathway and VEGF-C/-D in gastric cancer.

Methods: We collected surgically resected gastric adenocarcinoma specimens from 55 consented patients. Immunohistochemistry staining of p-Akt, p-mTOR, VEGF-C, VEGF-D were performed and scored by two independent pathologists. The results were presented as staining intensity and positive staining cell rate. We also measured lymphatic vessel density (LVD) by D2-40 staining. Different dosages of p-Akt inhibitor LY294002 (12.5 μM, 25 μM, 50 μM) and p-mTOR inhibitor Rapamycin (25 nM, 50 nM, 100 nM) were given to gastric cancer cell line SGC-7901 in vitro. The inhibition rate of cell growth was tested by MTT at 24 h, 48 h and 72 h, respectively and protein expressions of Akt, p-Akt, mTOR, p-mTOR, VEGF-C and VEGF-D were examined by Western blot.

Results: The positive staining rates of p-Akt, p-mTOR, VEGF-C and VEGF-D in 55 gastric cancer clinical specimens were 74.54%, 85.45%, 72.73% and 58.18%. p-Akt and p-mTOR were positively correlated with VEGF-C and VEGF-D (p < 0.01). The LVD increased with incremental tendency of staining intensity of p-Akt, p-mTOR, VEGF-C and VEGF-D. LY294002 or Rapamycin significantly suppressed SGC-7901 cell growth and the inhibition rate was dose and time dependent (p < 0.001). In addition, the protein expression of p-Akt and p-mTOR were positively correlated with that of VEGF-C and VEGF-D (p < 0.05).

Conclusions: The level of LVD in gastric cancer specimens was significant higher than that of normal gastric tissue and was positively correlated with p-Akt, p-mTOR, VEGF-C and VEGF-D. Inhibition of p-Akt and p-mTOR, in vitro, decreased tumor cell VEGF-C and VEGF-D significantly. Therefore, we concluded that lymphangiogenesis of gastric cancer might be related to Akt/mTOR-VEGF-C/VEGF-D axis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biomarkers, Tumor
Chromones / pharmacology
Enzyme Inhibitors / pharmacology
Female
Humans
Immunohistochemistry
Male
Morpholines / pharmacology
Neovascularization, Pathologic / metabolism*
Proto-Oncogene Proteins c-akt / metabolism*
Signal Transduction / drug effects
Stomach Neoplasms / metabolism*
Stomach Neoplasms / pathology*
TOR Serine-Threonine Kinases / metabolism*
Vascular Endothelial Growth Factor C / metabolism*
Vascular Endothelial Growth Factor D / metabolism*

Substances

Biomarkers, Tumor
Chromones
Enzyme Inhibitors
Morpholines
Vascular Endothelial Growth Factor C
Vascular Endothelial Growth Factor D
2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one
Proto-Oncogene Proteins c-akt
TOR Serine-Threonine Kinases