The Expression of Apoptosis-Related Genes Bcl-2 and Bax Protein and Apoptosis Positivity in Cervical Carcinoma during Irradiation

To evaluate the apoptosis positivity, the expression of Bcl-2, bax proteinsin 30 patients with squamous cell cervix carcinoma before and after radiotherapy. Methods: By usingimmuno-histochemical and TDT-dUTP nick end labelling techniques, 30 cases of squamous cell cervicalcarcinoma were analyzed. Results: The apoptosis positivity before and after irradiation was 76.7%and 100% respectively, with the difference being significant (P 【 0.05); The positive rates of Bcl-2protein before and after irradiation were 73.3% and 46.7% respectively, with the difference beingsignificant (P 【 0.05); The positive rates of bax protein before and after irradiation were 86% and100% respectively, with the difference being significant (P 【 0.05). Conclusion: bax and Bcl-2protein play an important role in apoptosis induced by fractionated radiation therapy. Apoptosisinduced by irradiation is contributed to upregulation of bax protein or downregulation of Bcl-2protein.

Expression of Bmi-1,P16,and CD44v6 in Uterine Cervical Carcinoma and Its Clinical Significance

Objective Bmi-1, a putative proto-oncogene, is a core member of the polycomb gene family, which is expressed in many human tumors. The p16 protein negatively regulated cell proliferation, whereas CD44v6 is associated with proliferation as an important protein. Additionally, CD44v6 is an important nuclear antigen closely correlated to tumor metastasis. Tlle present study aims to investigate the expression and significance of Bmi-1, p16, and CD44v6 in uterine cervical carcinoma （UCC）. Methods A total of 62 UCC, 30 cervical neoplasic, and 20 normal cervical mucosal tissues were used ill the current study. The expression of Bmi-1, p16, and CD44v6 in these tissues was determined using immunohistochemical assay. The relationships among the expression of these indices, the clinicopathologic features of UCC, and the survival rate of UCC patients were also discussed. The correlation between Bmi-1 protein expression and p16 or CD44v6 protein in UCC was analyzed. Results The expression of Bmi-l, p16, and CD44v6 was significantly high in cervical carcinoma compared with that in tlle cervical neoplasia and normal colorectal mucosa （P〈0.05）. The over-expression of Bmi-1 protein in UCC was apparently related to the distant metastasis （P〈0.01） and the tumor, nodes and metastasis-classification, i.e. the TNM staging, World Health Organization （P〈0.05）. Nevertheless, the positive expression of p16 protein in UCC was not significantly associated with the clinicopathologic features （P〉0.05）. The Kaplan-Meier survival analysis showed that the over-expression of Bmi-1 significantly decreased the survival rate of UCC patients （P〈0.05）. A strong correlation indicated that there was statistical significance between the expression of Bmi-1 and CD44V6 proteins in UCC （r=0.419, P=0.001）. Conclusions The over-expression of Bmi-1 and CD44v6 protein closely correlate to the tumorigenesis, metastasis, and prognosis of UCC. Bmi-I and CD44v6 may be used to predict the prognosis of cervical carcinoma. Bmi-1 may indirectly regulate the expression of CD44v6 in UCC patients. The positive expression of p16 protein is possibly associated with the tumorigenesis, but not with the metastasis or prognosis of UCC.

Inhibiting PI3K/Akt Pathway Increases DNA Damage of Cervical Carcinoma HeLa Cells by Drug Radiosensitization

This study examined the role of PI3K/Akt pathway in radiosensitization of DNA damage of cervical carcinoma cells.The 50% inhibition concentration(IC50) of cisplatin and docetaxel in HeLa cells was detected by Mono-nuclear cell direct cytotoxicity assay(MTT) in vitro.HeLa cells were treated by cisplatin/docetaxel of 10 percent of IC20 alone or combined with LY294002 for 24 h,and then radiated by different doses of X-ray.The cell survival ratio was obtained by means of clone formation.One-hit multi-target model was fitted to the cell survival curve to calculate dose quasithreshold(Dq),mean lethal dose(D0),2Gy survival fraction(SF2) and sensitization enhancement ratio(SER).The pAkt and total Akt expression was detected by Western blotting and DNA damage by neutro-comet electrophoresis.The HeLa cells were randomly divided into 7 groups in terms of different treatments:Control;radiation treatment(RT) group;LY294002+RT group;cisplatin+RT group;docetaxel+RT group;LY294002+cisplatin+RT group;LY294002+docetaxel+RT group.The apoptosis ratio of each group was measured by flow cytometry.The results showed that docetaxel and cisplatin significantly enhanced the phosphorylation of Akt in radiation-treated HeLa cells.The Dq,D0 and SF2 in LY294002-contained groups were lower than those in docetaxel or cisplatin+RT group.The SER in the LY294002+docetaxel+RT group was 1.35 times that of the docetaxel+RT group,and that in the LY294002+cisplatin+RT group 1.26 times that of the cisplatin+RT group.The Comet electrophoresis showed that tail distance in the LY294002+cisplatin+RT group or LY294002+docetaxel+RT group was longer than in the cisplatin+RT group or docetaxel+RT group.The apoptosis ratio in the LY294002+cisplatin+RT group or LY294002+docetaxel +RT group was higher than in the cisplatin+RT group or docetaxel+RT group.It was concluded that inhibiting PI3K/Akt pathway can increase the effect of docetaxel and cisplatin on the radiosensitivity of HeLa cells and DNA damage resulted from radiation.

Human papillomavirus 16 physical status detection in preinvasive and invasive cervical carcinoma by multiplex real-time polymerase chain reaction

Objective： To explore an ideal approach for detecting the physical status of HPV-16 in clinic use and to investigate the integrated HPV-16 in CINs and cervical cancer. Methods： Multiplex real-time PCR method was established to quantify the copy numbers of E2 and E6 genes （E2/E6） for analysis of the physical status of HPV-16 DNA and this assay was compared to Southern blot analysis. HPV-16-containing paraffin-embedded tissues including 49 CINs and 51 cervical squamous cancers were detected using the method. Results： （1） The cutoff ratio of E2/E6 to distinguish pure episomal from mixed HPV-16, was 0.81 in the multiplex real-time PCR; （2） The agreement rate between multiplex real-time PCR and Southern blot was 81.5% （the Kappa statistic was 0.844, P〈0.001）; （3） HPV-16 DNA existed in an episomal form in 57.1% and mixed form in 42.9% of CIN I lesions; The concomitant form of HPV-16 （〉70%） constituted the majodty in CIN Ⅱ and CIN Ⅲ; HPV-16 DNA mostly integrated into the host chromosome （s） in squamous cervical cancers （68.6%）; （4） The incidence of HPV-16 integration was increased with the degree of cervical lesions; （5） The frequency of pure integrated HPV-16 in stage Ⅱ＋Ⅲ （88%） was significantly higher than that in stage Ⅰ （33.3%）. Conclusion： （1） Mutiplex real-time PCR provides a rapid, sensitive and reliable method for clinic detection of the physical state of HPV-16 DNA; （2） The integration of the HPV-16 DNA is a very eady and important event in the progression from preinvasive to invasive cervical cancer; （3） The pure integrated status of HPV-16 in cervical cancer may be associated with poor prognosis of cervical cancer, but further study will be needed to prove its prognostic significance.

Anti-tumor Effects of a Recombinant Fowlpox Virus Expressing Apoptin on Human Cervical Carcinoma in Vivo and in Vitro

Apoptin is a chicken anemia virus-derived,p53-independent,bcl-2-insensitive apoptotic protein with the ability to specifically induce apoptosis of various human tumor cells,but not of normal diploid cells.To explore the application of apoptin in tumor gene therapy,we used a recombinant fowlpox virus expressing apoptin protein （vFV-Apoptin） to investigate the anti-tumor effectes of vFV-Apoptin on human cervical carcinoma（HeLa） cells in vivo and in vitro through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide（MTT） assay,acridine orage/ethidium bromide（AO/EB） and annexin V staining test,respectively.The results show that vFV-Apoptin inhibites the proliferation of HeLa cells in vitro through inducing the apoptosis of HeLa cells,and the inhibition effect of vFV-Apoptin has a dose-effect and time-effect relationship.The results of animal models show that vFV-Apoptin significantly inhibits tumor growth,extends the lifespan of animals and improves the mean survival.Experimental results indicate that vFV-Apoptin has a potential application in the tumor gene therapy.

EFFECTS OF CURCUMIN ON PROLIFERATION AND APOPTOSIS OF HUMAN CERVICAL CARCINOMA HeLa CELLS IN VITRO

Objective: To investigate the regulatory effect of curcumin on proliferation and apoptosis in human cervical carcinoma cell line HeLa in vitro. Methods: Human cervical carcinoma cell line Hela was cultured in vitro. HeLa cells were treated with 10~50 mmol/L curcumin for 24~72 h and the growth inhibition rates of HeLa cells were measured by MTT method. Cell apoptosis was inspected by electron microscopy. In addition, the expression of bcl-2, bcl-xl and caspase-3 protein in HeLa cell were observed by SP immunohistochemistry. Results: Curcumin inhibited the proliferation of HeLa cells on a dose-depending manner. Peak of subG1 appeared on DNA histogram in FCM. A portion of the cells presented the characteristic morphological changes of apoptosis under the electron microscope. The bcl-2, bcl-xl expression was decreased while Caspase-3 expression was increased. Conclusion: Curcumin could significantly inhibit the growth of HeLa cells; inducing apoptosis through up-regulating Caspase-3 and down-regulating expression of bcl-2 and bcl-xl was probably one of its molecular mechanisms.

Expressions of cyclooxygenase-2 and matrix metalloproteinase-9 in cervical carcinoma and their clinical significance

Objective: To investigate the expressions of cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-9 in cervical carcinoma and their clinical significance. Methods: Immunohistochemistry SP method was used to detect the expres- sions of COX-2 and MMP-9 in 72 cases of invasive carcinoma of cervix (ICC) and 16 cases of normal cervical epithelium remote from tumor (NCE). The relationships between the expressions of COX-2, MMP-9 in ICC and some characteristics relating to clinical pathology of cervical carcinoma such as histological grading, lymph node metastasis, stromal invasion and FIGO stage were analyzed statistically. Results: The rates of the positive expressions of COX-2 and MMP-9 in ICC were significantly higher than those in NCE. COX-2: 88.9% (64/72) in group ICC and 12.5% (2/16) in group NCE, P = 0.000; MMP-9: 94.4% (68/72) in group ICC and 43.8% (7/16) in group NCE, P = 0.000. The expression of COX-2 was positively correlated with lymph node metastasis (r = 0.296, P = 0.012) and stromal invasion (r = 0.257, P = 0.029). The expression of MMP-9 was positively correlated with FIGO stage (r = 0.329, P = 0.005) and histological grading (r = 0.351, P = 0.003). The expression of COX-2 was positively correlated with the expression of MMP-9 in ICC (r = 0.297, P = 0.011). Conclusion: The overexpressions of COX-2 and MMP-9 were closely related to the invasion and growth of cervical carcinoma. The tissue with the overexpression of COX-2 had strong invasion ability. COX-2 and MMP-9 had synergistic effect on proliferation, invasion and metastasis of cancer cells. Detecting the coexpression of COX-2 and MMP-9 may be of value in further understanding the biological behavior and predicting the prognosis of cervical carcinoma.

VARIATION ANALYSIS OF HPV16 CELL-TYPE-SPECIFIC ENHANCER IN CERVICAL CARCINOMA

Objective To investigate the cell-type-specific enhancer (CTSE) in HPV16 and its variation in cervical carcinoma. Methods CTSEs were detected by polymerase chain reaction (PCR) in 58 cervical carcinoma from Shaanxi province; in addition variation of CTSEs was analyzed through single-strand conformation polymorphisms (SSCP). Results HPV16 CTSEs were detectable in 34 of 58 (57%) specimens and mutant rate was 41%(14/34) and the main mutations of chosen randomly variant CTSE (CTSEv) happened at YY1 binding sites in addition to glucocoticoid response elements (GRE). Conclusion CTSE in some specimens of Shaanxi province was obviously different from that in HPV16 wild type and variant CTSE might affect the transcriptional regulation of LCR on viral P97, which regulates over-expression of viral oncogenes in cervical carcinoma.

Relationship between Microsatellite Alterations of RASSF1A Gene and Development of Cervical Carcinoma

Objective： To explore the relationship between microsatellite alterations of RASSFIA gene and the development of cervical carcinoma, and its relationship with HPV16 infection. Methods： Two sites of microsatellite polymorphism of RASSFIA gene were selected. Polymerase chain reaction （PCR） technique was used to detect LOH and MSI in 50 cases of cervical carcinoma and 40 cases of cervical intraepithelial neoplasia （CIN）, and to detect the infection state of HPV16. Results： At D3S1478 and D3S4604, the LOH rates of cervical carcinomas were 32.6% （14/43） and 48.9% （23/47）, the MSI rates were 14% （6/43） and 19.1% （9/47）, respectively. The LOH rates of CINs were 31.4% （11/35） and 39.5% （15/38）, the MSI rates were 11.4% （4/35） and 15.8% （6/38）, respectively. There were no significant differences between cervical carcinomas and CINs in respect to their positive rates of LOH and MSI at D3S1478 and D3S4604 （P〉0.05）. There were significant differences in LOH rates at D3S1478 and D3S4604 between the stage Ⅰ-Ⅱ and Ⅲ-Ⅳ cervical carcinomas and between the well/moderately differentiated cervical carcinomas and the poorly differentiated cervical carcinomas （P〈0.05）. The positive rates of LOH and MSI for CIN Ⅲ and noninvasive cervical carcinomas were higher than those in CIN Ⅰ-Ⅱ. The rates of infection of HPV16 in cervical cancer was obviously higher than that in CIN and in normal cervical tissues （P〈0.05）, and the incidence of LOH of RASSFIA gene was higher in HPV16（＋） than that in HPV16（-） （P〈0.05）. Conclusion： The RASSFIA gene change is a relatively late event in cervical carcinomas. The detection of LOH and MSI of RASSFIA gene might be helpful to the early diagnosis and the screening of cervical carcinoma. It might also be useful for predicting the prognosis of cervical carcinoma.

Effects of Res on proliferation and apoptosis of human cervical carcinoma cell lines C33A,SiHa and HeLa

Objective:To explore the effects of Res on the proliferation and apoptosis of human cervical cancer cell lines C33A,SiHa and HeLa.Methods:Inhibition rates by different concentrations of Res were calculated using MTT method.Apoptosis rates and cell cycles were measured and examined by flow cytometry(FCM).Morphological configuration of apoptotic cells were observed under the fluorescence microscope.Results:The growth of cancer cells was inhibited by Res of varied concentrations in a time-and dose-dependent manner(P<0.01).The cells showed characteristic apoptosis morphologic changes under fluorescence microscope.Res exerted no effects on cell cycles.Conclusion:Res inhibits the growth of cervical cell lines C33A,SiHa and HeLa by inducing cell apoptosis in a time-and dose-dependent manner.

Risk Factors of Cervical Carcinoma and Countermeasures against Them in Mountainous Area of Wufeng County, China

Cases (n=44) with squamous cell cervical cancer (SCCA) and age-matched healthy controls (n=176) were analyzed. Significant difference due to human papillomavirus (HPV) infection, ages at the first marriage, ages at the first sexual intercourse, ages at the first birth given to baby, number of gravidities, number of deliveries, Body Mass Index (BMI), education level of women and their husbands (p<0.05) was observed. According to multivariate logistic regression analysis, four factors have entered the model (p<0.05), including HPV infection [OR (odds ratio)=26.13, 95%CI (confidence interval)=9.40?72.60], education level of women (OR=0.41, 95%CI=0.21?0.79), education level of spouses (OR=0.45, 95%CI=0.22?0.94), BMI (OR=0.73, 95%CI=0.57?0.93). Moreover, HPV infection is relative to education level of women (r=?0.14), and their spouses (r=?0.21), age at the first marriage (r=?0.20), age at the first birth given to baby (r=?0.20) and BMI (r=?0.15).

A PRELIMINARY STUDY ON SURVIVIN AND BCL-2 EXPRESSION IN CERVICAL CARCINOMAS

Objective To study the expression of a novel inhibitor of apptosis and survivin in cervical carcinoma and its relationship to the expression of Bcl-2.Methods Using SP immunohistochemical technique, we examined the expression of survivin and Bcl 2 in 59 cervical invasive squamous cell carcinomas.Results Survivin was expressed in 41 of 59 cases(69.5%) of cervical carcinomas. In contrast, no expression of survivin in normal cervical tissues was observed. Overexpression of survivin was related to the tumor grade and clinical stage. Survivin positive cases were strongly associated with Bcl 2 expression(80% versus 35.7%; P <0.005).Conclusion Apoptosis inhibition by survivin abnormal expression, alone or in cooperation with Bcl 2, may participate in the onset and progression of cervical carcinoma. Survivin is a new diagnostic/therapeutic target in cervical cancer.

PROGNOSTIC FACTORS IN CERVICAL CARCINOMA

Objective: To evaluate factors for prognosis of cervical carcinoma. Methods: Expressions of mn23- HI, erbB3 and erbB4 were examined by immunohistochemical staining. The apoptosis was detected in situ by the TdT mediated duip-biotin nick end-labeling (TUNEL) technique. Mitotic cell were counted by HE dyeing. Results: FIGO stage and lymph node metastasis were the most important factors for evaluating prognosis in adenocarcinoma or squamous cell carcinoma. AI/MI was positively correlated with 5-year survival of cervical carcinoma. Positive expression of nm23-H1 combed with negative expression of erbB4 [nm23-H1(+)/erbB4(?)] predicted good prognosis for adenocarcinoma. In multivariable Cox regression analysis, only FIGO stage and AI/MI were into equation. Conclusion: FIGO stage and AI/MI were independent evaluating parameter for adenocarcinoma or squamous cell carcinoma.

GENETIC INSTABILITY IN CERVICAL CARCINOMA

Objective: The role of human papillomavirus (HPV) in the development of cervical carcinoma has been clearly established but other factors could be involved in cervical tumorigenesis such as loss of heterozygosity (LOH) and microsatellite instability (MI). The aim of the present study was to investigate the genetic instability in cervical carcinoma tissues and provide evidence for discovering new tumor suppressor genes and screening diagnostic molecular marker of cervical carcinoma. Methods: Fifty primary cervical carcinoma samples from high-incidence area were analyzed by PCR for HPV16 infection, LOH and microsatellite instability. Results: HPV16 was detected in 88% of the cases. Sixty-six percent of total cases showed LOH with no more than 3 different loci per case. The highest frequency of the allelic loss was found in D18S474 (18q21, 40.5%). MI was detected in 4 cases (8%) only. Conclusion: Different percentages of LOH on specific chromosomal regions were found and MI was very infrequent in cervical carcinoma. The putative suppressor gene(s) could be located on specific chromosome regions such as 18q, and genetic instability could be involved in cervical tumorigenesis.

Effect of aspirin alone or combined with cisplatin on human cervical carcinoma HeLa cells

Objective： To study the effect and mechanism of aspirin alone or combined with cisplatin （DDP） on human cervical carcinoma HeLa cells. Methods： HeLa cells were treated by different concentrations of aspirin, DDP alone or both. The inhibitory effect on cell growth was analyzed by MTT and colony-forming assay. Cell apoptosis was measured with flow cytometry. The mRNA levels ofBcl-2, Bax and NF-κB（P65） were studied by RT-PCR. Results： MTT assay showed that aspirin inhibited HeLa cell proliferation in a time-and dose-dependant maoner. Aspirin decreased clone numbers in colony formation assay. Aspirin also induced apoptosis of HeLa cells in a dose- and time-dependent manner as detected by flow cytometry. The inhibition effects on proliferation, colony formation and apoptosis were significantly enhanced when cells were treated with both aspirin and DDP. RT-PCR demonstrated that aspirin decreased the transcription of Bcl-2 and NF-κB, and increased expression of Bax gene. Conclusion： Aspirin can induce apoptosis in HeLa cells. Combination of aspirin and DDP displays a synergistic effect. The possible mechanism might be that aspirin downregulates the mRNA levels of Bcl-2 and NF-κB gene and upregulates the expression of Bax.

Relationship between Cell Proliferation and Apoptosis in Cervical Carcinoma

Objective To study the relationship between cell proliferation and apoptosis in cervical carcinoma and its clinical significance. Methods The cell proliferation and apoptosis of cervical epithelial cells in archival formalin-fixed, paraffin-embedded tissue sections of normal cervix, cervical intraepithelial neoplasms (GIN) and cervical squamous carcinoma were tested by using immunohistochemistry assay and DNA nick end-labeling technigue. The proliferation index (PI) and apoptosis index (AI) were calculated and their correlation with clinical and pathological data was analyzed.Results PI was gradually increased, but the AI and AI/PI ratio decreased from normal cervical epithelium, GIN to cervical carcinoma. There was no significant relationship among cell proliferation, apoptosis, clinical stages and pathological grades. High AI was always associated with a poor prognosis of the patients.Conclusion Cell proliferation and apoptosis allow to distinguish among normal epithelium, GIN and cervical carcinoma and are useful for the assessment of the malignant potential of tumor tissues.

ASSAY OF S100+ LANGERHANS' CELLS IN CERVICAL CARCINOMA

Langerhans cells (LCs) in the normal cervix (control, 19 cases), cervical carcinoma in situ( CIS, 19 cases) and invasive cervical carcinoma (30 cases), interdigitatlng cells (IDCs) and follicular dendritic cells (FDCs) in obturator lymph node draining Invasive cervical carcinoma were quantitatively assessed by ABC immunohistochemical staining using anti-S100 protein antibody. The results indicated that S100+ LCs in sltu, S100+ IDCs and S100+ FDCs In obturator lymph node showed dendritic features with a specific distribution. Number of LCs in situ in Invasive carcinoma increased significantly when compared with CIS and control groups. There was no change in LCs number between grade Ⅱ and Ⅲ of squemous cell carcinoma. Number of IDCs was significantly less in stage Ⅱ than in stage Ⅰ . FDCs number In different Invasive depthes and clinical stages showed no obvious change. The results suggest that progression of cervical carcinoma is closely related to decrease of LCs hi situ and IDCs in regional lymph node. Predominant Immune response of the host to cervical carcinoma should be cellular immunity.

THE INFECTION OF EBV FOR CERVICAL EPITHELIUM-A NEW CAUSITIVE AGENT IN THE DEVELOPMENT OF CERVICAL CARCINOMAS?

Epstein-Barr virus was considered as a caustive agent for Burrkitt' s lymphoma and non-malignant B lymphocytes proliferation. The recent studies revealed the striking association of the Infection of EBV with the development of human epithelial tumors. 43 specimens of normal exfoliated cervical epithelial cells, 47 biopsies of chronic cervlcitis and 80 tissue samples of cervical carcinomas were tested for the presences of EBV W fragments by using dot blot hybridization method. The results showed that the detectable rates of EBV DNA sequences In the normal exfoliated epithelium, the chronic cervlcitis and cervical carcinomas were 44.16%, 12.77% and 13.75%, respectively. Eleven EBV positive DNA samples from cervical cancers were also examined for the presence of HPV DNA. The result showed 9 out of 11 were HPV DNA positive, the cultanious infectious rate of both viruses was about 81.81%.In this paper, the EBV genomes existed In the part of biopsies of cervical carcinomas were first reported. The results Implied that the development of cervical cancer might be associated with asymptomatic EBV Infection In early stage and might be the result from the synergistic carcinogenesis of EBV with other cervical oncovinises, especially with HPV.

Inhibition of Ku80 by RNAi enhances the radiosensitivity of cervical carcinoma cell line SiHa

Objective： To study the radiosensitivity of SiHa cells with Ku80 inhibition by RNAi. Methods： pKu80-siRNA and pNeg-siRNA were constructed and then transfected into SiHa cells. Western blot and RT-PCR were applied to measure the expression of Ku80. After 10 Gy irradiation with 6 MV X-ray, cells were harvested at 20 h, 28 h and 48 h, and analyzed by flow cytometry for apoptosis rate. The SF2 and α, β values of cells were acquired by clone formation array. Results： Two stable transfection cell clones SiHa/Ku80-siRNA and SiHa/Neg-siRNA were screened from the pKu80-siRNA and pNeg-siRNA transfected cells. Western blot and RT-PCR indicated that the expression of Ku80 was suppressed by the Ku80-siRNA, The apoptosis rates of SiHa/Ku80-siRNA were higher than control cells at 28 h and 48 h after X-ray irradiation （P 〈 0.05）. The SF2 value of SiHa/Ku80-siRNA （0.422） was lower than that of SiHa/Neg-siRNA cells （0.587） or untransfected cells （0.583）, and the a value of SiHa/Ku80-siRNA was 0.295 ± 0.016, higher than that of SiHa/Neg-siRNA （0.176 ± 0.010） or control cells （0.188 ± 0.011）. Conclusion： Inhibition of Ku80 could enhance the radiosensitivity of SiHa, which showed that Ku80 could be a good target for molecular therapy.

Detection of Human Papillomavirus Type 16 DNA in Cervical Carcinomas

Accurate typing of the different human papillomavirus types is csscntial in view of the differ-ent pathological potential of the common virus types of human papillomavirus （HPV） present in thecervix. We have developed hybridization, washing and autoradiography conditions that minimize thecross-hybridization among different specific types of HPV so as to allow clear - cut type assignmentthrough practical dot blot hybridization technique using nylon membrane and 35S - labeled HPV - 16DNA probe. Under these conditions seventeen of thirty （56.7%） of squamous cell carcinomas of thecervix uteri obtained from Tianjin women were detected in the presence of HPV - 16 DNA.