卵巢癌是婦科癌症中致死率最高的惡性腫瘤，其造成高致死率的最重要原因之一是我們對於卵巢癌的分子致病機轉尚未瞭解十分透徹，目前很多研究顯示，卵巢癌並非一個單一疾病，根據不同的組織型態及分子基因特性，它包含不同的subgroups並且統稱為卵巢癌，為了有效提高卵巢癌的存活率，找出卵巢癌致病機轉中的相關基因是刻不容緩的。根據本實驗室之前利用microarray分析成大醫院60位卵巢癌病患檢體 (clear-type: 12人，endometrioid-tpe: 11人，serous-type: 28人，mucinous-type:
9人)，在比較正常卵巢癌上皮組織與卵巢癌病患的組織中，我們發現了Castor Zinc Finger 1 (CASZ1)在卵巢癌病患當中有異常高量的表現，文獻指出CASZ1是一個轉錄因子，在神經母細胞瘤中為抑癌基因，會促進神經母細胞瘤細胞的分化並抑制腫瘤的生成，但CASZ1在卵巢癌當中的異常表現似乎又說明了它在卵巢癌當中具有不同的生物功能，而目前並沒有文獻多加說明CASZ1與卵巢癌之間的關聯性，因此在本篇研究我們試圖去探討CASZ1與卵巢癌之間的調控關係。
我們利用real time-PCR相對定量CASZ1在卵巢癌組織與正常卵巢上皮組織中的mRNA表現量，確認CASZ1在卵巢癌組織中與正常卵巢上皮組織相比確實有較高量的表現量，並且比較卵巢癌細胞株與正常卵巢上皮細胞的CASZ1表現量，發現CASZ1 mRNA及protein表現量在卵巢癌細胞株也有較高量的表現，透過Kaplan-Meier survival的分析，我們也發現CASZ1表現量較高的卵巢癌病患，會有較差的progression-free survival，為了瞭解CASZ1對卵巢癌細胞的影響，我們利用核糖核酸干擾的作用，透過病毒感染的方式抑制MCAS和RMUG這兩株細胞CASZ1基因表現，並藉由細胞增生、移行、侵襲等實驗，來找出CASZ1在卵巢癌細胞中可能具有的生物功能，我們發現當MCAS和RMUG這兩株卵巢癌細胞株內生性CASZ1基因的表現量被穩定抑制後，雖然不影響細胞增生的能力，但會顯著的降低細胞移行與侵襲的能力，而已知filopodia參與在細胞移動的過程中，因此進一步透過phallioidin staining，以共軛焦顯微鏡觀察細胞邊緣指狀突起結構(protrusive, finger-like structures)的filopodia，可以發現抑制CASZ1的表現量後，細胞邊緣有filopodia形成的細胞數目比例明顯降低，除此之外，我們也利用細胞群落試驗來評估CASZ1對腫瘤形成能力的影響，發現抑制CASZ1基因的表現量後，卵巢癌細胞在soft agar形成群落的能力降低50-60%。同時我們也在TOV21G及A2780CP70這兩株細胞中大量表現CASZ1a及CASZ1b，進行反證以及觀察這2種isoform是否在卵巢癌當中都具有相同的生物功能，發現CASZ1a及CASZ1b皆會促進卵巢癌細胞的移行及侵襲的能力，並且藉由西方墨點法偵測CASZ1a及CASZ1b對表皮細胞間質化標記蛋白(EMT marker)的影響，可以看到在CASZ1a或CASZ1b大量表現時，N-cadherin和α-smooth muscle actin (α-SMA)的protein表現量也隨之增加，而E-cadherin的protein表現量則會減少，另外，在小鼠尾靜脈注射卵巢癌細胞模擬癌細胞轉移的試驗中，可以觀察到在穩定抑制CASZ1表現的組別中，小鼠肺臟轉移的小結節(nodules)數目明顯受到抑制。
有別於在神經母細胞瘤中扮演抑癌基因的角色，從實驗結果可以發現CASZ1在卵巢癌細胞中的異常表現，反而會促進細胞移行及侵襲的能力並且可能影響卵巢癌的進展，而從動物實驗也發現抑制CASZ1的表現明顯降低卵巢癌細胞的轉移能力，藉由上述結果，我們將進一步找尋CASZ1在卵巢癌中可能轉錄調控的下游基因，有助於日後卵巢癌的診斷及治療。

Ovarian cancer is the most lethal gynecological malignancy. One of the main reasons for this highest fatality rate is that the molecular pathogenesis of ovarian cancer is poorly understood. To improve clinical outcomes, it would be desirable to identify of ovarian cancer-associated genes for uncovering the pathogenesis. Based on microarray analysis performed in our laboratory, a dysregulated gene CASZ1, which encodes a zinc finger transcription factor and functions as a tumor suppressor, was identified and found that expressed at higher levels in ovarian cancer. The apparently contrasting expression patterns and the association of CASZ1 with ovarian cancer are unknown. Here, the elevated expression of CASZ1 was confirmed by quantitative RT-PCR in ovarian cancer cell lines and tumor tissues. Moreover, higher CASZ1 expression was significantly associated with poor progression-free survival. To investigate the functional relevance of CASZ1 for malignant behavior in ovarian cancer, CASZ1 was stably knocked down using lentiviral-mediated shRNA constructs in MCAS and RMUG cell lines. Inhibition of CASZ1 expression significantly reduced the migration and invasion ability of ovarian cancer cells, though did not appear to affect cell proliferation. Using phalloidin staining, we observed a significant decrease in filopodia formation at leading edge in MCAS and RMUG cell lines silencing CASZ1. Besides, knockdown of CASZ1 showed a 50-60% decrease in soft agar clonogenicity. We also transfected CASZ1a and CASZ1b in TOV21G and A2780CP70 cell lines and demonstrated that both CASZ1a and CASZ1b promote cell migration and invasion. Furthermore, when injected CASZ1-depleted cells via the tail vein into NOD/SCID mice, lung tumor nodules were significantly decreased. These results suggested that CASZ1 may play a role in ovarian cancer cell migration and invasion, and that inhibition of CASZ1 expression could serve as a therapeutic strategy to overcome ovarian cancer.

Anglesio, M. S., J. George, H. Kulbe, M. Friedlander, D. Rischin, C. Lemech, J. Power, J. Coward, P. A. Cowin and C. M. House (2011). "IL6-STAT3-HIF signaling and therapeutic response to the angiogenesis inhibitor sunitinib in ovarian clear cell cancer." Clinical cancer research 17(8): 2538-2548.
Anglesio, M. S., S. Kommoss, M. C. Tolcher, B. Clarke, L. Galletta, H. Porter, S. Damaraju, S. Fereday, B. J. Winterhoff and S. E. Kalloger (2013). "Molecular characterization of mucinous ovarian tumours supports a stratified treatment approach with HER2 targeting in 19% of carcinomas." The Journal of pathology 229(1): 111-120.
Banerjee, S. and S. B. Kaye (2013). "New strategies in the treatment of ovarian cancer: current clinical perspectives and future potential." Clinical Cancer Research 19(5): 961-968.
Bast, R. C., B. Hennessy and G. B. Mills (2009). "The biology of ovarian cancer: new opportunities for translation." Nature Reviews Cancer 9(6): 415-428.
Charpentier, M. S., K. S. Christine, N. M. Amin, K. M. Dorr, E. J. Kushner, V. L. Bautch, J. M. Taylor and F. L. Conlon (2013). "CASZ1 promotes vascular assembly and morphogenesis through the direct regulation of an EGFL7/RhoA-mediated pathway." Developmental cell 25(2): 132-143.
Chen, V. W., B. Ruiz, J. L. Killeen, T. R. Coté, X. C. Wu, C. N. Correa and H. L. Howe (2003). "Pathology and classification of ovarian tumors." Cancer 97(S10): 2631-2642.
Christine, K. S. and F. L. Conlon (2008). "Vertebrate CASTOR is required for differentiation of cardiac precursor cells at the ventral midline." Developmental cell 14(4): 616-623.
Gorringe, K. L., J. George, M. S. Anglesio, M. Ramakrishna, D. Etemadmoghadam, P. Cowin, A. Sridhar, L. H. Williams, S. E. Boyle and N. Yanaihara (2010). "Copy number analysis identifies novel interactions between genomic loci in ovarian cancer." PloS one 5(9): e11408.
Kuo, K.-T., T.-L. Mao, S. Jones, E. Veras, A. Ayhan, T.-L. Wang, R. Glas, D. Slamon, V. E. Velculescu and R. J. Kuman (2009). "Frequent Activating Mutations of< i> PIK3CA</i> in Ovarian Clear Cell Carcinoma." The American journal of pathology 174(5): 1597-1601.
Kurman, R. J. and I.-M. Shih (2010). "The Origin and pathogenesis of epithelial ovarian cancer-a proposed unifying theory." The American journal of surgical pathology 34(3): 433.
Liu, Z., A. Naranjo and C. J. Thiele (2011). "CASZ1b, the short isoform of CASZ1 gene, coexpresses with CASZ1a during neurogenesis and suppresses neuroblastoma cell growth." PloS one 6(4): e18557.
Liu, Z., X. Yang, Z. Li, C. McMahon, C. Sizer, L. Barenboim-Stapleton, V. Bliskovsky, B. Mock, T. Ried and W. London (2011). "CASZ1, a candidate tumor-suppressor gene, suppresses neuroblastoma tumor growth through reprogramming gene expression." Cell Death & Differentiation 18(7): 1174-1183.
Liu, Z., X. Yang, F. Tan, K. Cullion and C. J. Thiele (2006). "Molecular cloning and characterization of human< i> Castor</i>, a novel human gene upregulated during cell differentiation." Biochemical and biophysical research communications 344(3): 834-844.
Mattila, P. K. and P. Lappalainen (2008). "Filopodia: molecular architecture and cellular functions." Nature reviews Molecular cell biology 9(6): 446-454.
Network, C. G. A. R. (2011). "Integrated genomic analyses of ovarian carcinoma." Nature 474(7353): 609-615.
Prat, J. (2012). "New insights into ovarian cancer pathology." Annals of Oncology 23(suppl 10): x111-x117.
Prat, J. (2012). "Ovarian carcinomas: five distinct diseases with different origins, genetic alterations, and clinicopathological features." Virchows Archiv 460(3): 237-249.
Romero, I. and R. C. Bast Jr (2012). "Minireview: human ovarian cancer: biology, current management, and paths to personalizing therapy." Endocrinology 153(4): 1593-1602.
Siegel, R., D. Naishadham and A. Jemal (2013). "Cancer statistics, 2013." CA: a cancer journal for clinicians 63(1): 11-30.
Singer, G., R. Oldt, Y. Cohen, B. G. Wang, D. Sidransky, R. J. Kurman and I.-M. Shih (2003). "Mutations in BRAF and KRAS characterize the development of low-grade ovarian serous carcinoma." Journal of the National Cancer Institute 95(6): 484-486.
Tapia, G. and I. Diaz-Padilla (2013). "Molecular Mechanisms of Platinum Resistance in Ovarian Cancer."
Virden, R. A., C. J. Thiele and Z. Liu (2012). "Characterization of critical domains within the tumor suppressor CASZ1 required for transcriptional regulation and growth suppression." Molecular and cellular biology 32(8): 1518-1528.
von Hilchen, C. M., R. M. Beckervordersandforth, C. Rickert, G. M. Technau and B. Altenhein (2008). "Identity, origin, and migration of peripheral glial cells in the< i> Drosophila</i> embryo." Mechanisms of development 125(3): 337-352.
Wiegand, K. C., S. P. Shah, O. M. Al-Agha, Y. Zhao, K. Tse, T. Zeng, J. Senz, M. K. McConechy, M. S. Anglesio and S. E. Kalloger (2010). "ARID1A mutations in endometriosis-associated ovarian carcinomas." New England Journal of Medicine 363(16): 1532-1543.
Yap, T. A., C. P. Carden and S. B. Kaye (2009). "Beyond chemotherapy: targeted therapies in ovarian cancer." Nature Reviews Cancer 9(3): 167-181.