Relationships between the Presence of HPV 16/18 DNA in Peripheral Blood Cells and Clinical Parameters of Head and Neck Cancers in Taiwan

• Main Authors: Shang-Jung Yang, 楊尚融
• Other Authors: J. S.-M. Tschen
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/28245622750174089637

碩士 === 國立中興大學 === 生命科學院碩士在職專班 === 95 === According to the data of the ranks of cancer death from the Department of Health, Executive Yuan, Taiwan, between 1996 and 2002, oral carcinoma raised its rank from outside the 10th to the 5th , and nasopharyngeal carcinoma remained within the most 10 prevalent cancers . The results of epidemiological studies have shown betel quid chewing, tobacco smoking and alcohol drinking are well-known risk factors in the etiology of head and neck cancers (HNCs). There are, however, 10~20% of HNCs that occur in the absence of exposure to the well-known risk factors, suggesting the presence of possible additional biological risk factors. Clinically, we can observe that many HPV-associated head and neck squamous cell papillomas progressed to carcinomas after several years of follow-up. According to the epidemiological and molecular data, HPV may be one of the promoting factors of head and neck carcinogenesis, but their relationships are not well documented. Our previous studies have shown HPV 16/18 DNA can be detected in tumor tissue and blood circulation of HNCs patients. However, the corelation of HPV infection between the tumor tissue and blood circulation is not clear. Thus, the purpose of this study is to analyze the corelation of HPV infection between the tumor tissue and blood circulation and clinical relationships between the presence of HPV in peripheral blood cells and patients with HNCs. Nested-PCR was employed to detect HPV 16/18 DNA in the blood circulation of 40 HNCs patients and 207 noncancer controls. The results showed that the prevalence rate of HPV 16/18 in the blood circulation of HNCs cases was significantly higher than that of noncancer controls (22.5 % vs. 3.38 %, P < 0.001). A significantly higher HPV 16 prevalence was detected among the cancer patients with older age or advanced stages of tumors (age <56：5 %，age ≧56：35 %；P= 0.044；stage I,II,III：5 %，advanced stage：35 %；P=0.044), but survival rate between cancer and noncancer patients was not significantly different. Therefore, we suggested that patients with HPV-positive cancers seem to have a favourable prognosis, and the explanation for this might be that HNCs associated with HPV, as an additional biological risk factor, showed differences in carcinogenesis and mediated pathways in comparison with those with the traditional carcinogenic risk factors. In this study, we further detect HPV 16 DNA copy number in blood circulation and tissues in HNCs patients. HPV copy number can be detected in the blood circulation in 2 patients with HNCs and 3 patients in their tumor tissues. And all five patients have similar clinical characteristics which are always involving in multiple sites or tumor recurrence. By this finding, we can conclude that HPV 16 DNA copy number detected in the blood circulation or tumor tissues may represent viral replication taking place within the body resulting in tumorigenesis continuously. Since the patients with higher HPV copy number have higher incidence of recurrence and metastasis, HPV DNA copy number can be quantified and serve as a meaningful marker for disease status, chance of recurrence and treatment result in HNCs patients in the future.