Expression of HIWI in human esophageal squamous cell carcinoma is significantly associated with poorer prognosis
1 Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, PR China
2 Divisions of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, 0310, Norway
3 Faculty Division The Norwegian Radium Hospital, Faculty of Medicine, University of Oslo, Oslo, 0316, Norway
4 Department of Respiratory Medicine, the Second Hospital Affiliated to Dalian Medical University, Dalian, 116023, PR China
5 Department of Biochemistry and Molecular Biology, Peking University School of Oncology, Beijing Institute for Cancer Research, Beijing, 100142, PR China
6 Department of Oncology, Anyang Tumor Hospital, Anyang, 455000, PR China
7 Department of Surgery, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, 0310, Norway
8 Faculty Division The Norwegian Radium Hospital, Faculty of Medicine, University of Oslo, Oslo, 0316, Norway
BMC Cancer 2009, 9:426 doi:10.1186/1471-2407-9-426Published: 8 December 2009
HIWI, the human homologue of Piwi family, is present in CD34+ hematopoietic stem cells and germ cells, but not in well-differentiated cell populations, indicating that HIWI may play an impotent role in determining or maintaining stemness of these cells. That HIWI expression has been detected in several type tumours may suggest its association with clinical outcome in cancer patients.
With the methods of real-time PCR, western blot, immunocytochemistry and immunohistochemistry, the expression of HIWI in three esophageal squamous cancer cell lines KYSE70, KYSE140 and KYSE450 has been characterized. Then, we investigated HIWI expression in a series of 153 esophageal squamous cell carcinomas using immunohistochemistry and explored its association with clinicopathological features.
The expression of HIWI was observed in tumour cell nuclei or/and cytoplasm in 137 (89.5%) cases, 16 (10.5%) cases were negative in both nuclei and cytoplasm. 86 (56.2%) were strongly positive in cytoplasm, while 49 (32.0%) were strongly positive in nuclei. The expression level of HIWI in cytoplasm of esophageal cancer cells was significantly associated with histological grade (P = 0.011), T stage (P = 0.035), and clinic outcome (P < 0.001), while there was no correlation between the nuclear HIWI expression and clinicopathological features.
The expression of HIWI in the cytoplasm of esophageal cancer cells is significantly associated with higher histological grade, clinical stage and poorer clinical outcome, indicating its possible involvement in cancer development.