Ekspresi p53 dan p21 waf/cip-1 pada karsinoma nasofaring

SUHARTO, Agus, dr. Harijadi, SpPA

2005 | Tesis | PPDS I Patologi Anatomi

Latar Belakang. Karsinoma nasofaring diketahui tumbuh cepat di tempat maupun di regio sekitarnya. Pertumbuhan jumlah sel tumor merupakan hasil selisih dari proliferasi dan kematian sel. Ditemukan ekspresi kuat p53 dan p21 pada karsinoma nasofaring. Keduanya merupakan protein yang dapat mengendalikan proliferasi sel. Protein p21 di picu oleh protein p53 dan meghambat kerja kompleks kinase yang tergantung siklin dan menghambat kelanjutan siklus pembelahan sel. Di sel tumor yang sedikit atau tidak mengandung protein p53 ditemukan ekspresi p21 yang menurun bahkan tidak ditemukan. Sebaliknya beberapa penelitian menunjukkan pada spesimen tanpa p53 ditemukan peningkatan ekspresi p21 pada sel karsinoma nasofaring. Ekspresi p53 pada karsinoma nasofaring tidak berhubungan dengan derajat histologis, stadium klinik, jenis kelamin atau umur. Pada penelitian lain ditemukan protein p53 dapat menghambat pertumbuhan sel karsinoma nasofaring pada tikus. Untuk mengetahui peran protein p53 terutama hubungan ekspresi p53 dan p21. Penelitian ini ingin mengetahui ekspresi protein p53 dan p21 pada biopsi jaringan nasofaring. Tujuan. Menganalisa hubungan antara ekspresi p53 dengan p21 pada karsinoma nasofaringdan hubungan ekspresi p53 dan p21 dengan stadium klinis dan jenis histologis. Cara penelitian. Empat puluh sembilan sampel di cat secara imunohistokimia dengan monoklonal anti p53 dan p21. Evaluasi ekspresi p53 dan p21 dilakukan dengan menghitung jumlah inti sel yang terwarnai, bila di temukan sel dengan persentasi di atas 10% disebut positif dan bila dibawah 10% disebut negatif.. Data dianalisis dengan statistik non parametrik yakni Pearson chi square menggunakan SPSS for window Hasil Penelitian: Ditemukan ekspresi kuat p53(89,8%) dan p21(67,3%) pada karsinoma nasofaring. Didapatkan hubungan yang bermakna diantara ekspresi p53 dan p21 (p<005) dan ekspresi keduanya tberhubungan dengan stadium klinis dan tipe histologis karsinoma nasofaring Kesimpulan: Ada hubungan yang bermakna antara ekspresi p53 dengan p21,ekspresi p21 merupakan efek fungsional dari ekspresi p53 yang berlebihan. Dan tidak didapatkan hubungan yang bermakna antara ekspresi p53 dan p21 dengan stadium klinis dan tipe histologis karsinoma nasofaring.

Background: Nasopharyngeal carcinoma is known to grow rapidly in the local and regional areas. The growing number of tumor cell is a result of the competiting effect between cell proliferation and cell death. High expression of p53 and p21/WAF1 on nasopharyngeal carcinoma were present. Both p53 and p21 are protein controls cells proliferation. The protein p21 waf/cip-1 is induced by the p53 gene and inhibits the activity of several cyclin dependent kinase complexes and blocks cell cycle progression. In tumour cells, that have lost p53 protein, or contain an altered of p53, p21 waf/cip-1 levels are dramatically reduced or totally absent. In Contrast some study have lost p53 with increasing p21 waf/cip- 1expression on NPC tumour cells. p53 expression in NPC does not correlate with histological grading, clinical stage, sex or age. In the other study p53 could inhibit the NPC cell growth in nude mice. An order to attempt the role of p53; whether expression of p53 and p21 have any correlation of these protein. This study will explored the expression of p53 and p21 in nasopharyngeal carcinoma tissue biopsie. Objective: The aim of this study is to analyze the correlation between expression of p53 and p21 in nasopharyngeal carcinoma. , and related the expression of both p53 and p21 with staging and histologic type. Method: Fourty nine nasopharyngeal carcinoma specimens were stained immunohistochemically with MoAb anti p53 and anti p21waf to evaluated p53 expressions and p21waf expression. Expression of p53 and p21 waf was quantified the number of nuclear staining, which the percentage less 10% is referred as negative and more than 10% as positive. The result were analized using non parametric statistical adopted by Pearson chi square using SPSS for Window. Result : High expression of both p53(89,8%) and p21(67,3%) in nasopharyngeal carcinoma, there was significant correlation ( p<0,05) between p53 and p21 expression nasopharyngeal carcinoma tumor cell. and the expression of both p53 and p21 are not related to staging and histologic type on nasopharyngeal carcinoma. Conclution: There was significantly correlation between p53 and p21, sugested expression of p21 waf/cip-1 would be reflect the functional status of p53 more precisely than p53 accumulation, and in this study there was not significantly correlation between both expression of p53 and p21 with stage and histologic type of nasopharyngeal carcinoma.

Kata Kunci : Karsinoma Nasofaring,Ekspresi p53 dan p21, Nasopharyngeal carcinoma, p53, p21 ,histologic type and staging