人類乳頭瘤病毒與口腔疣狀癌的關係

Abstract

背景及目的:過去許多研究證實高危險 (high-risk) 人類乳頭瘤病毒 (Human papillomavirus, HPVs) 和子宮頸及口腔鱗狀細胞癌，有相當有意義之相關。但是於口腔疣狀癌的發生上，人類乳頭瘤病毒所扮演的角色，還並不清楚。於本研究中我們將探討全部基因型人類乳頭瘤病毒，特別是高危險基因型人類乳頭瘤病毒和口腔疣狀癌之發生，是否有相關。 方法: 為了探討人類乳頭瘤病毒在口腔疣狀癌致癌機轉上所扮演的角色，本實驗於75個口腔疣狀癌標本及30個正常口腔黏膜標本中，純化出去氧核糖核酸 (DNA)，利用兩組位在人類乳頭瘤病毒中，一致性較高的L1部份的引子(MY09/GP6+ 和 GP5+/GP6+)，進行兩次聚合酶鏈反應 (polymerase chain reaction, PCR)，來增加人類乳頭瘤病毒的DNA量，以供偵測。同時配合人類乳頭瘤病毒生物晶片 (gene chip)， 及DNA定序技術，來作人類乳頭瘤病毒定型 (typing)，以此方法可在一次反應中，偵測出39種不同人類乳頭瘤病毒的基因型。 結果: 我們發現，就全部基因型人類乳頭瘤病毒的陽性率而言，口腔疣狀癌標本 (15%, 11/75) 和正常口腔黏膜標本 (20%, 6/30)，及口腔習慣相關口腔疣狀癌標本 (14%, 10/71) 和口腔習慣無相關口腔疣狀癌標本 (25%, 1/4)，皆無顯著差異 (P>0.05)；就高危險、低危險或不明危險基因型人類乳頭瘤病毒的陽性率而言，口腔疣狀癌標本(分別為4%, 11% 或 15%) 和正常口腔黏膜標本 (分別為17%, 3% 或0%, P>0.05)，及口腔習慣相關口腔疣狀癌標本 (分別為3%, 11% 或 3%) 和口腔習慣無相關口腔疣狀癌標本 (分別為25%, 0% 或 0%)，也皆無顯著差異 (P>0.05)；然而，就人類乳頭瘤病毒基因型 16和多種人類乳頭瘤病毒基因型同時出現於同一標本的陽性率而言，正常口腔黏膜標本 (分別為17% 和 13%) 明顯大於口腔疣狀癌標本(分別為0% 和 1%, P<0.05)。於11個人類乳頭瘤病毒陽性的口腔疣狀癌標本中，低危險基因型 (11, 72和74) 之出現頻率 (73%)，高於高危險基因型 (18和31) 之出現頻率 (27%)，及不明危險基因型 (53和62) 之出現頻率 (18%)，但其差別無統計意義。 結論: 因和正常口腔黏膜標本相較，口腔疣狀癌，特別是口腔習慣相關口腔疣狀癌，之全部基因型及高危險基因型人類乳頭瘤病毒的陽性率仍然偏低，我們認為口腔疣狀癌，特別是口腔習慣相關口腔疣狀癌，和全部基因型及高危險基因型人類乳頭瘤病毒，無明顯相關。

Background and purpose: Previous studies have shown a significant association of high-risk human papillomavirus (HPV) types with cervical and oral squamous cell carcinomas. However, the etiologic role of HPV in the development of oral verrucous carcinoma (OVC) is still unclear. In this study, we tried to elucidate whether there was a close relationship between all or high-risk HPV types and OVCs. Methods: DNA samples were purified from 75 OVC specimens and 30 normal oral mucosa (NOM) specimens. A nested polymerase chain reaction (PCR) was used to amplify the consensus L1 region of the HPV genome in DNA samples using two sets of HPV primers (MY09/GP6+ and GP5+/GP6+). This procedure combined with a gene chip HPV typing and DNA sequencing was able to detect 39 HPV subtypes in our samples. Results: We found no significant difference in the overall HPV-positive rate between OVC samples (15%, 11/75) and NOM samples (20%, 6/30, P>0.05) as well as between OH-associated OVC samples (14%, 10/71) and non-OH-associated OVC samples (25%, 1/4, P>0.05). In addition, there was also no significant difference in the positive rate of high-risk, low-risk or unclear-risk HPV types between OVC samples (4%, 11% or 3%, respectively) and NOM samples (17%, 3% or 0%, respectively, P>0.05) as well as between OH-associated OVC samples (3%, 11% or 3%, respectively) and non-OH-associated OVC samples (25%, 0% or 0%, respectively, P>0.05). However, HPV type 16 and multiple HPV types were detected more frequently in NOM samples (17% and 13%, respectively) than in OVC samples (0% and 1%, respectively, P<0.05). In 11 HPV-positive OVC samples, low-risk types (11, 72 and 74) were found more frequently (73%, 8/11) than high-risk types (18 and 31; 27%, 3/11) or unclear-risk types (53 and 62; 18%, 2/11), but the difference was not significant (P>0.05). Conclusion: The relatively low overall and high-risk HPV-positive rates in our OVC samples, especially in OH-associated OVC samples, compared to those in NOM samples suggest that there is no significant association of all and high-risk HPV types with OVCs, especially OH-associated OVC.