Correlation of hypoxia inducible factor-1alpha with lymphatic metastasis via vascular endothelial growth factor-C in human esophageal cancer.

Hypoxia inducible factor (HIF)-1alpha is a transcription factor that regulates the transcription of genes associated with cell proliferation and vascular development. In various cancer tissues, HIF-1alpha is associated with clinicopathological factors, such as the tumor size, histological grade, and lymph node status. Although HIF-1alpha plays a critical role in tumor growth by inducing vascular endothelial growth factor (VEGF), it is unclarified whether HIF-1alpha affects lymphatic metastasis. The purpose of this study is to clarify the correlation of HIF-1alpha protein expression with lymph node metastasis in esophageal squamous cell carcinoma (ESCC). The expressions of HIF-1alpha and VEGF-C, which is one of the main lymphangiogenic factors, were examined in five ESCC cell lines and 48 surgical specimens of ESCC. HIF-1alpha and VEGF-C mRNAs were expressed in all the five ESCC cell lines as determined by RT-PCR analysis. Immunohistochemically, 34 of the 48 patients (70.8%) were positive for HIF-1alpha and 29 patients (60.4%) were positive for VEGF-C. Clinicopathologically, HIF-1alpha expression correlated with lymphatic invasion and VEGF-C expression (P = 0.003 and P = 0.01, respectively). Furthermore, HIF-1alpha expression tended to correlate with lymph node metastasis (P = 0.09). These findings suggest that HIF-1alpha plays a role in lymphatic invasion and lymph node metastasis through the induction of VEGF-C in ESCC.

Katsuta M ，Miyashita M ，Makino H ，Nomura T ，Shinji S ，Yamashita K ，Tajiri T ，Kudo M ，Ishiwata T ，Naito Z ... -  《EXPERIMENTAL AND MOLECULAR PATHOLOGY》

[Expression of hypoxia-inducible factor-1alpha and vessel endothelial growth factor in esophageal squamous cell carcinoma and clinico-pathological significance thereof].

To investigate the expression of hypoxia-inducible factor (HIF)-1alpha and vessel endothelial growth factor (VEGF) and their relations with the clinicopathological features of esophageal squamous cancer. Esophageal squamous cancer tissues and normal end squamous epithelium tissues were collected from 42 patients during operation. Real-time quantitative PCR was used to detect the mRNA expression of HIF-1alpha and VEGF and immunohistochemistry was used to detect the protein expression of HIF-1alpha and VEGF. The relations between the expression of HIF-1alpha, VEGF and depth of tumor invasion, histological grade, lymphatic invasion, and lymph node metastasis were evaluated. The HIF-1alpha mRNA expression level was 5.88 + 1.12 in the esophageal squamous cancer tissue, higher, but not significantly, than that in normal end squamous epithelium tissue 4.76 +/- 1.26 (P = 0.014). The VEGF mRNA expression level in the esophageal squamous cancer tissue was 12.79 +/- 2.51, higher, but not significantly, than that in the normal end squamous epithelium tissue (10.92 +/- 2.23, P = 0.010). The HIF-1alpha and VEGF protein positive rates in esophageal squamous cancer tissue were 50% (21/42) and 76% (32/42) respectively, significantly higher than those in the normal esophageal tissue [14% (6/42) and 33% (14/42) respectively, P = 0.001, P = 0.000]. The expression of HIF-1alpha mRNA and VEGF mRNA in the esophageal squamous cancer were correlated with lymph node metastasis (including lymphatic invasion) (P = 0.063 and P = 0.073 respectively). HIF-1alpha immunoreactivity was localized in the nucleus and/or cytoplasm of the cancer cells. The expression of HIF-1alpha protein was correlated with lymph node metastasis and histological grade (P = 0.013 and P = 0.028 respectively). No correlation was found between HIF-1alpha mRNA and VEGF protein. HIF-1alpha may be regulated at transcription and post-transcription levels in addition to protein level. It also plays an important role in lymphatic metastasis of esophageal squamous cancer and tumor malignancy degree. So HIF-1alpha and VEGF may serve as predictors of progression in esophageal squamous cell carcinoma and as potential targets for anti-angiogenesis therapy of esophageal squamous cell carcinoma.

Yu ZT ，Zhao HF ，Shang XB 《-》

Levels of hypoxia-inducible factor-1alpha independently predict prognosis in patients with lymph node negative breast carcinoma.

Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that plays an important role in tumor growth and metastasis by regulating energy metabolism and inducing angiogenesis to survive cellular hypoxia. Increased levels of HIF-1alpha, the O(2)-regulated subunit of HIF-1, were noted during breast carcinogenesis. In this study, the prognostic value of HIF-1alpha expression and its correlation with various clinicopathologic variables in patients with invasive breast carcinoma were investigated. Expression levels of HIF-1alpha, HER-2/neu, estrogen receptor, and progesterone receptor were analyzed in 150 patients with early-stage breast carcinoma by immunohistochemistry. HER-2/neu gene amplification was investigated with automated fluorescent in situ hybridization. The mitotic activity index, histologic grade, and tumor type were assessed in hematoxylin and eosinstained specimens. Clinical data included disease-free survival, overall survival, lymph node status, and tumor size. The data were analyzed with two-sided univariate and multivariate tests, with P values < 0.05 considered significant. High levels of HIF-1alpha had an association of borderline significance with decreased overall survival (P = 0.059) and disease-free survival (P = 0.110) that was ascribed completely to the subgroup of women with lymph node negative tumors (n = 81 patients; P = 0.008 and P = 0.004, respectively). HER-2/neu immunoreactivity (P < 0.001) and gene amplification (P < 0.001), vascular endothelial growth factor expression (P = 0.016), and Ki-67 expression (P < 0.001) were correlated strongly with HIF-1alpha positivity, although none of those factors had an independent effect on survival. Increased levels of HIF-1alpha were associated independently with shortened survival in patients with lymph node negative breast carcinoma. Therefore, the use of immunohistochemical assessment of HIF-1alpha as a new predictor of poor outcome may improve clinical decision-making regarding adjuvant treatment of patients with lymph node negative breast carcinoma.

Bos R ，van der Groep P ，Greijer AE ，Shvarts A ，Meijer S ，Pinedo HM ，Semenza GL ，van Diest PJ ，van der Wall E ... -  《CANCER》

Hypoxia inducible factor-alpha expression correlates with vascular endothelial growth factor-C expression and lymphangiogenesis/angiogenesis in oral squamous cell carcinoma.

The number of blood vessels correlates with metastasis in solid tumors, including oral squamous cell carcinoma (OSCC). Hypoxia inducible factor-1alpha (HIF-1alpha) could play a role in tumor lymphangiogenesis by regulating the lymphatic expression of vascular endothelial growth factor-C (VEGF-C). HIF-1alpha protein expression, VEGF-C protein expression, lymphatic vessel density (LVD) and blood vessel density (BVD) in OSCC were investigated. HIF-1alpha and VEGF-C protein expression were investigated by means of immunohistochemistry in samples from 65 cases of OSCC. The density of the lymphatic microvessels and blood microvessels immunohistochemically stained by LYVE-1 and CD34 antibody, respectively, was calculated. The association between the HIF-1alpha expression and the clinicopathological parameters was evaluated. HIF-1alpha overexpression occurred in 43 out of the 65 tumor samples (66.2%), while VEGF-C overexpression was observed in 34 out of the 65 tumor samples (52.3%). Higher LVD was found in both high HIF-1alpha and high VEGF-C expression cases. HIF-1alpha overexpression was significantly correlated with VEGF-C overexpression (p = .018, Chi-square test), higher LVD (p < 0.001, Mann-Whitney U-test), and regional lymph nodal involvement (p = 0.004, Chi-square test) as well as UICC TMN classification (p = 0.043, Chi-square test), respectively. In addition, higher BVD existed in the high HIF-1alpha and VEGF-C expression groups (p < 0.001, Mann-Whitney U-test). HIF-1alpha might play a crucial role in regional lymph node metastasis as a regulator of lymphangiogenesis and angiogenesis in OSCC with a possible novel pathway involving VEGF-C. Therefore, HIF-1alpha might be a particularly promising target for controlling regional lymph node metastases by a combination of antiangiogenic and anti-lymphangiogenic effects in OSCC.

Liang X ，Yang D ，Hu J ，Hao X ，Gao J ，Mao Z ... -  《ANTICANCER RESEARCH》

Hypoxia inducible factor-1alpha correlates with VEGF-C expression and lymphangiogenesis in breast cancer.

The transcription factor Hypoxia inducible factor-1alpha (HIF-1alpha) plays a crucial role in tumor progression by regulating angiogenesis, cell survival and drug resistance. HIF-1alpha is also implicated in biological functions under normoxic conditions and recent data provide evidence for a possible role in tumor lymphangiogenesis by regulating the lymphatic vascular endothelial growth factor-C (VEGF-C). In breast cancer, lymphatic vessel invasion (LVI) by tumor cells and subsequent metastasis to axillary lymph nodes is a critical point in progression of the disease with severe therapeutical and prognostic implications. Aim of this study is to investigate the role of HIF-1alpha in VEGF-C expression, lymphangiogenesis, and LVI in lymph node positive breast cancer. Lymphatic microvessel density (LMVD), LVI, HIF-1alpha and VEGF-C protein-expression were evaluated by immunohistochemistry in 119 cases of lymph node positive invasive breast cancer. There was a significant correlation between HIF-1alpha and VEGF-C (p = 0.026, r = 0.204, Spearman's coefficient of correlation). Further a significant association between HIF-1alpha-expression and the amount of peritumoral lymphangiogenesis LMVD was seen (p = 0.014, Mann-Whitney test). LMVD correlated significantly with LVI (p<0.001, Mann-Whitney test). HIF-1alpha was an independent prognostic factor for overall and disease free survival in uni- and multivariate analysis (p = 0.027, 0.029, 0.025, respectively, Cox regression). Our data provide evidence for a possible role of HIF-1alpha as regulator of tumor-associated lymphangiogenesis in human breast cancer and emphasizes the promising status of HIF-1alpha as a therapeutical target against tumor progression and metastasis.

Schoppmann SF ，Fenzl A ，Schindl M ，Bachleitner-Hofmann T ，Nagy K ，Gnant M ，Horvat R ，Jakesz R ，Birner P ... -  《BREAST CANCER RESEARCH AND TREATMENT》