人類肺癌與胃癌組織粒線體DNA變異之研究

Study of Mitochondrial DNA Alternations in Human Lung Cancer and Gastric Cancer

陳怡菁(Yi-Ching Chen)

指導教授 ： 許立松

中山醫學大學/醫學院/生化暨生物科技研究所/碩士(2005年)

https://doi.org/10.6834/CSMU.2005.00057

摘要

在人類的許多癌症中偵測到粒線體的突變，包括肝癌、大腸癌、乳癌、肺癌與胃癌等。粒線體 DNA D-loop 區域的突變與4977 bp 斷損突變為最常偵測到的突變。然而，在癌症形成的過程中粒線體的功能與粒線體 DNA 的扮演的角色，至目前還未有定論。
本論文中使用聚合酶連鎖反應 (PCR) 偵測31位胃癌與19位肺癌病人之腫瘤組織與周邊非腫瘤組織之粒線體 DNA 之D-loop區域突變及4977 bp 斷損突變、多重斷損突變與拷貝數的改變，並且分析D-loop區域的突變與多重斷損突變之間的相關性。結果顯示在胃癌(43.8%)與肺癌(84.2%)病人之週邊非腫瘤組織中，粒線體 DNA 4977 bp斷損突變的比例高於腫瘤組織。同樣的結果也出現在粒線體 DNA多重斷損突變中，胃癌病人非腫瘤組織 (68.4%) 與肺癌病人非腫瘤組織 (31.3%)，皆高於癌症組織。偵測粒線體DNA多重斷損突變的結果中，在胃癌8720-16245 bp，肺癌的8634-16067 bp找到新的斷損突變長度。在粒線體 DNA D-loop 區域突變的發生比例，胃癌有中51.6%，肺癌有26.3%，同時在核苷酸 (np) 303-319的位置出現高比例的突變，並且發現粒線體 DNA D-loop、4977 bp 斷損突變、多重斷損突變較常在胃癌末期與肺癌早期發生，也伴隨著粒線體拷貝數的減少。此外，在胃癌中當拷貝數減少時，觀察到粒線體 DNA D-loop、4977 bp 斷損突變與多重斷損突變之間的相關性較肺癌明顯。
綜合以上的結果顯示當粒線體 DNA 發生D-loop、4977 bp 斷損突變、多重斷損突變而呈現不穩定的狀態時，可能造成粒線體的功能損傷，而參與癌症的生成。並且在不同的癌症中粒線體 DNA 突變的現象會因組織特異性的不同，而有不同的結果。透過這些粒線體 DNA 的偵測，希望能提供在癌症的診斷、治療與致病機轉上一些參考。

關鍵字

粒線體DNA, 肺癌, 胃癌

並列摘要

Somatic mutation in mitochondrial DNA (mtDNA) has been detected in many cancers, including hepatocellular carcinoma (HCC), colorectal cancer, breast cancer, lung cancer and gastric cancer. The mtDNA D-loop region and 4977 bp deletion were found to be a “hot spot” for mutation of the tumors. However, the role of alternation in mitochondrial function and mtDNA in carcinogenesis still remains unclear.
In this thesis, I used PCR to detect mtDNA D-loop mutation, 4977 bp deletion, multiple deletion and change of copy number in tumor tissues and corresponding non-tumor tissues of 31 gastric and 19 lung cancer patients. The result revealed that 43.8% of gastric and 84.2% of lung cancer patients were detected to carry the 4977 bp deletion of mtDNA. The incidence of the 4977 bp deletion in the non-tumor portion was higher than that in the tumor portion. The similar results were observed in multiple deletion 68.4% of the gastric and 31.3% of the lung cancer patients were detected to carry multiple deletions in their non-tumor portions. The incidence of multiple deletions in the non-tumor portions was higher than that in the tumor portions. In the result of mtDNA multiple deletion it were found that new mutation in nucleotide position 8720-16245 bp in gastric cancer, and nucleotide position 8634-16067 bp in lung cancer. The incidence of somatic mutation in mtDNA D-loop region was 51.6% in gastric cancer, and 26.3% in lung cancer, respectively. The alternations in nucleotide position 303-309 were high frequent mutations in these cancer. Moreover, I found the mtDNA D-loop region, 4977 bp deletion, and the multiple deletion occurred frequently in gastric cancer of last phases and in lung cancer of early phases. On the other hand, the decrease in the mtDNA copy number in gastric cancer, and the observed mtDNA D-loop mutations, 4977 bp deletion, and multiple deletion was more significantly than that in lung cancer. These observations suggest that mtDNA instability, together with the alternation in the D-loop region, 4977 bp mutation, and multiple deletion of mtDNA, may lead to mitochondrial dysfunction and play an important role in the carcinogenesis of human cancer. However, alternation in mtDNA mutation was tissue specific. These findings provide important information for cancer diagnosis, cancer therapy and understanding the mechanism of carcinogensis of human cancer.

並列關鍵字

mitochondrial DNA, lung cancer, gastric cancer

參考文獻

human gastric cancer. Cancer Cells, 1991. 3(2): p. 49-52.

C.p53 mutations in human cancers. Science, 1991. 253

gene in breast cancer development. Cancer Treat Res,

1992. 61: p. 59-68.

4.Hirayama, T., Epidemiology of cancer of the stomach with