Expression And Significance Of FHIT Gene In Bladder Transitional Cell Carcinoma

Background and Objective: Bladder cancer is the most common malignant tumor in the genitourinary system in china, Ninety percent of all the cancers are bladder transitional cell carcinoma(BTCC), its initiation is correlated with many factors. But its exact mechamism has been unknown. At present, the generation of tumor is supposed to be the activation of oncogenes and inactivation of tumor suppossor genes by mutation, rearrangement and deletion which make genes lose the function of inhibiting apoptosis and proliferation. The study of gene play an important role in the initiation and development of bladder cancer. By testing gene, we can throw light on the mechanism of BTCC, providing an effective evidence for chosing the way in clinical preventing and treating BTCC. FHIT was a newly discovered one whose unnormal expression was first found in renal clear cell carcinoma. Recently , most tests indicated that FHIT gene also expressed unnormally in many types of tumors including the head and neck, lung, breast , stomach, colon, pancerata, rectrol, chordoma and osteosarcoma, and the expression of FHIT protein lowered even deleted. But the relationship between FHIT gene and the initiation and development of BTCC is not clearly understood. So it is of great importance to explore the role in the initiation and development of BTCC.In the present study, we detected the expression of FHITmRNA in 62 specimensof BTCC and 35 specimens of normal bladder tissues by RT-PCR, meanwhile, detecting the expression of FHIT protein and the proliferation activity of PCNA in the same tissues by immnohistochemistry staining, to try to explore the of role in the initiation and development of BTCC and the relationship between FHIT gene and the proliferation of tumor.Materials and Methods: Tissues were obtained from 62 patients who underwent open surgery ,TURBT and biopsy in the first affiliated hospital of Zhengzhou University from Sep,2002 to Nov 2003. 35 normal spcimens were obtained at the same time from the common patients. All the BTCC tissues were pathologically confirmed and no patient had received radiotherapy, chemotherapy and immunothrapy before operation. There were 46 males and 16 females ,the age ranged from 29 to 78 years old(mean: 62.5 years old). All the specimens were cut into two, one was put into liquid nitrogen, the other was fixed with 10% formalin and embedded routinely with paraffin, every section was 4Mm. 37 spcimens were superficial in nature(Tjs~Ti), 25 specimens were invasive(T2~T4) according to UICC-TNM staging system. 9 specimens belong to Grade I; 18, Grade II; 35 , Grade III lymphatic metastasis of was 8. according to WHO. Multiclonal rabbit anti-FHIT and monoclonal mouse anti-PCNA nuclear antigen were used to detect the expression of FHIT protein and PCNA antigen in BTCC and normal bladder tissues by two-stepped immunohistochemistry staining.FHIT protein was reorded according to a four-tiered scoring system that incorporates both intensity of staining and the percentage cells stained(the rate of positive cells to all the cells): >75% was 4 scores; 51%~75% was 3; 11%~50% was 2; <10% was l;negative was O.staining compared with background colour.abscent, 0;light yellow, l;brown yellow,2;brown;3.A composite score of the FHIT protein level was obstained by multiplying the intensity and extent for each tissue section composite scores 2 considered positive for FHIT protein expression. PCNA antigen was indicated with FHIT. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the FHIT gene in the same tissues, p-actin was the criterion. The deletion of the FHIT protein was indicated relatively with rate of expression .PCNAwas considered positive if granule appeared in the nucleus (stained endothelial cells were not counted). About one thousand cells were counted in the ten high power fields.Randomly,positive cells were selected and counted,the averenge number of positive cells was considered as PCNA proliferating index.Spss 10.0 software was used to analyzed the data, a= 0.05 was consi...