p53 tumor suppressor gene protein expression in cervical cancer: relationship to prognosis

Prognostic and Predictive Clinical and Biological Factors in HPV Malignancies

Human papillomavirus (HPV) causes the majority of oropharyngeal, cervical, and anal cancers, among others. These HPV-associated cancers cause substantial morbidity and mortality despite ongoing vaccination efforts. Aside from the earliest stage tumors, chemoradiation is used to treat most HPV-associated cancers across disease sites. Response rates are variable, and opportunities to improve oncologic control and reduce toxicity remain. HPV malignancies share multiple commonalities in oncogenesis and tumor biology that may inform personalized methods of screening, diagnosis, treatment and surveillance. In this review we discuss the current literature and identify promising molecular targets, prognostic and predictive clinical factors and biomarkers in HPV-associated oropharyngeal, cervical and anal cancer.

Therapeutic potential of p53 reactivation in cervical cancer

Cervical cancer (CC) is one of most common malignancies affecting women worldwide. To date, surgical resection is the only effective radical remedy for CC at its early stages, while the prognosis of metastatic or recurrent CC is very poor. Dysfunction of the tumor suppressor p53 due to aberrant expression, post-translational modification, mutations, SNPs, and LOH as well as sequestration by viral antigens and MDM2/HDM2-mediated degradation is closely associated with the therapeutic insensitivity and relapse of many malignancies, including CC. Accumulating studies have demonstrated that restoration of p53 activity can induce cell cycle arrest and apoptosis, eliminate radio- and chemotherapy resistance, and inhibit tumor growth in CC cells. Therefore, activation of wild-type p53 as well as restoration of p53 function seems appealing as a therapeutic strategy. In this review, we focus on the potential roles of p53 reactivation in CC treatment and their underlying molecular mechanisms towards the development of novel therapies.

Comprehensive gene and pathway analysis of cervical cancer progression

Cervical Cancer is one of the leading causes of cancer-associated mortality in women. The present study aimed to identify key genes and pathways involved in cervical cancer (CC) progression, via a comprehensive bioinformatics analysis. The GSE63514 dataset from the Gene Expression Omnibus database was analyzed for hub genes and cancer progression was divided into four phases (phases I-IV). Pathway enrichment, protein-protein interaction (PPI) and pathway crosstalk analyses were performed, to identify key genes and pathways using a criterion nodal degree ≥5. Gene pathway analysis was determined by mapping the key genes into the key pathways. Co-expression between key genes and their effect on overall survival (OS) time was assessed using The Cancer Genome Atlas database. A total of 3,446 differentially expressed genes with 107 hub genes were identified within the four phases. A total of 14 key genes with 11 key pathways were obtained, following extraction of ≥5 degree nodes from the PPI and pathway crosstalk networks. Gene pathway analysis revealed that CDK1 and CCNB1 regulated the cell cycle and were activated in phase I. Notably, the following terms, 'pathways in cancer', 'focal adhesion' and the 'PI3K-Akt signaling pathway' ranked the highest in phases II-IV. Furthermore, FN1, ITGB1 and MMP9 may be associated with metastasis of tumor cells. STAT1 was indicated to predominantly function at the phase IV via cancer-associated signaling pathways, including 'pathways in cancer' and 'Toll-like receptor signaling pathway'. Survival analysis revealed that high ITGB1 and FN1 expression levels resulted in significantly worse OS. CDK1 and CCNB1 were revealed to regulate proliferation and differentiation through the cell cycle and viral tumorigenesis, while FN1 and ITGB1, which may be developed as novel prognostic factors, were co-expressed to induce metastasis via cancer-associated signaling pathways, including PI3K-Art signaling pathway, and focal adhesion in CC; however, the underlying molecular mechanisms require further research.

Clinicopathologic and molecular markers in cervical carcinoma: a prospective cohort study

BACKGROUND

Cervical cancer is a major health problem worldwide. Identification of effective clinicopathologic and molecular markers is vital to improve treatment stratification.

OBJECTIVES

The purpose of this study was to validate a set of well-defined clinicopathologic features in a large population-based, prospectively collected cervical cancer cohort to support their use in the clinic. Further, we explored p53 and human epidermal growth factor receptor 2 as potential prognostic markers in cervical cancer.

STUDY DESIGN

Tissue was collected from 401 patients with cervical cancer. Clinical data that included follow-up evaluations were collected from patient journals. Histopathologic data were evaluated and revised by an expert pathologist. The prognostic impact of selected clinicopathologic variables was analyzed in the whole cohort. Tissue microarrays were prepared from 292 carcinomas, and p53 and human epidermal growth factor receptor 2 protein levels were evaluated by immunohistochemistry. Fresh frozen samples from overlapping cervical carcinomas previously were subjected to human papilloma virus typing (n=94), whole exome (n=100) and RNA (n=79) sequencing; the results were available for our analyses.

RESULTS

Among the clinicopathologic variables, vascular space invasion, histologic type, and tumor size were verified as strong independent prognostic markers. High p53 protein levels were associated significantly with markers for aggressive phenotype and survival, also in multivariate survival analysis, but did not reflect TP53 mutational status. High human epidermal growth factor receptor 2 protein levels were identified in 21% of all tumors. ERBB2 amplification was associated with poor outcome (P=.003); human epidermal growth factor receptor 2 protein level was not.

CONCLUSIONS

Our findings support that the Féderation Internationale de Gynécologie et d'Obstétrique s guidelines should include vascular space invasion and tumor size 2-4 cm and that careful selection of histologic type is essential for stratification of patient risk groups. High p53 levels independently predict poor survival yet do not reflect mutational status in cervical cancer. Amplified ERBB2 significantly links to poor survival, while HercepTest does not. With optimal stratification, human epidermal growth factor receptor 2-based therapy may improve cervical cancer treatment.

The prognostic values of the expression of Vimentin, TP53, and Podoplanin in patients with cervical cancer

Purpose

Epithelial–mesenchymal transition (EMT), TP53, and Podoplanin have been implicated in the tumorigenesis and metastasis of human cancers. Nevertheless, the clinical significance of these markers in cancer patients is still not clear. In this study, we sought to determine the prognostic values of Vimentin, TP53, and Podoplanin in patients with cervical cancer.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis were performed to determine the messenger RNA and protein expression levels of Vimentin, TP53, and Podoplanin, respectively, in cervical squamous cell carcinoma and adjacent normal cervical tissues. Additionally, the expression levels of Podoplanin were also measured in 130 cervical cancer patients (FIGO stages Ib1–IIa2) using immunohistochemistry (IHC) staining.

Results

The mRNA expression levels of Vimentin, TP53, and Podoplanin were considerably elevated in cervical cancer tissues, compared with those in the adjacent normal cervical tissues. Additionally, the protein expression levels of Vimentin were closely correlated with the age of onset (P = 0.007), lymph node metastasis (P = 0.007), lymphatic invasion (P = 0.024), disease recurrence (P < 0.001), and the clinical prognosis of patients with cervical cancer (P < 0.001). Our multivariate analysis also suggests that Vimentin is an independent marker for survival in cervical cancer patients. Furthermore, the expression levels of Vimentin are negatively correlated with the proliferation marker Ki67 expression.

Conclusions

Our data show that Vimentin can serve as an independent prognostic marker for cervical cancer patients with primary surgery.

Registration number ChiCTR-TRC-06000236 Registered 15 December 2006

Dysregulation of CDK inhibitors and p53 in HPV-negative endocervical adenocarcinoma

Human papillomavirus (HPV)-negative adenocarcinoma (AC) is a minor subset of endocervical cancer, but its pathogenesis has yet to be elucidated. This study investigated the clinicopathologic features of HPV-negative endocervical AC (n=14) in comparison with HPV-positive endocervical AC (n=30), and further studied aberrations of cell-cycle regulators. Expression patterns of cyclin-dependent kinase inhibitors (p16, p14, p27, and p21) and p53 were evaluated immunohistochemically, and nuclear high-risk HPV DNA signals were detected by in situ hybridization and polymerase chain reaction. Immunoexpression of p16, p14, p27, p21, and p53 were observed in 90%, 67%, 77%, 40%, and 20% of HPV-positive ACs, and in 0%, 0%, 29%, 14%, and 57% of HPV-negative ACs, respectively. A higher frequency of lymph node metastasis and worse prognosis were significantly associated with HPV-negative AC. Our findings suggest that alteration of cyclin-dependent kinase inhibitors and p53 status may contribute to carcinogenesis and the clinical behavior of HPV-negative AC of the uterine cervix.

The prognostic value of p53 expression for patients with cervical cancer: a meta analysis

OBJECTIVE

A number of studies have evaluated the association of p53 expression with the cervical cancer clinical outcome, but the results were inconsistent.

STUDY DESIGN

Electronic search of PubMed was conducted to select studies. Studies which quantitatively evaluated the relationship between p53 expression and survival of the patients with cervical cancer were chosen, and hazard ratio (HR) with 95% confidence interval (CI) was used to assess the association.

RESULTS

The final meta-analysis contained 11 published studies including 1105 patients. Combined HRs suggested that p53 overexpression has an unfavorable impact on overall survival(OS) [HR=1.672, 95% confidence interval (CI): 1.144-2.444, P=0.008], and Caucasian cervical cancer patients OS[HR=1.942, 95% CI: 1.162-3.245, P=0.011].

CONCLUSIONS

p53 expression indicates a poor prognosis for Caucasian people with cervical cancer.

The Role of p53 Gene in Cervical Carcinogenesis

AIM

To investigate the role of p53 gene in cervical carcinogenesis.

MATERIALS AND METHODS

A total 50 cases and controls were taken after setting exclusion criteria. Venous blood (3 ml) samples were collected in sterile EDTA sterile vials. Both punch biopsy of cervical growth in cases and biopsy from cervix after hysterectomy in controls were performed. Genomic DNA was extracted from tissue and blood using standard protocol of Miller et al. 1994 using chloroform-phenol method. Gene was amplified using specific forward and reverse primers and p53 gene expressions were studied. The present study of p53 gene regulation analyzed the expression of 279-bp bands on 1.5 agarose gel.

OBSERVATIONS

Out of the total 50 samples of cases and controls, we were able to isolate DNA from 38 cases and 28 controls in blood and in 22 cases and 22 controls in tissue. In cases of carcinoma cervix, p53 expression is either downregulated or absent in 71.06 % of cases compared to 50 % of controls in blood and 72.73 % of cases compared to 59.09 % of controls in tissue, but these figures were not statistically significant (p = 0.67 and p = 0.167, respectively). p53 positivity rate was only in 27.78 % of squamous cell cancer and 50 % of adenocarcinoma. Three out of nine patients (33.3 %) with L.N. positive status have p53 gene positivity, whereas 23 % (3 out of 13) with L.N. negative status have p53 gene positivity, which is not significantly associated. In our study, p53 overexpression increases with the various stages of cervical cancer.

CONCLUSION

In our study, we found that there is the increased frequency of upregulation or overexpression of p53 gene in control in both blood (50 %) and tissue (40.9 %), but this association is statistically nonsignificant. In the present study, there is a lack of relationship between p53 overexpression and prognosis in the cervical cancer patients. However, our study lacked larger sample size which otherwise would have been able to lend support to truly significant findings through much larger combined and comparative datasets.

Sirtuin1 expression predicts the efficacy of neoadjuvant chemotherapy for locally advanced uterine cervical cancer

Cisplatin-based, cyclic balloon-occluded arterial infusion, neoadjuvant chemotherapy (NAC) has previously been reported to enable hysterectomy in patients with locally advanced cervical cancer. Sirtuin1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD⁺)-dependent histone deacetylase that deacetylates a number of proteins and is overexpressed in several human malignancies. Upregulation of SIRT1 has been reported to induce tumorigenesis and chemoresistance. To assess the role of SIRT1 in uterine cervical cancer, the outcomes in 62 patients aged <70 years with locally advanced International Federation of Gynecology and Obstetrics (FIGO) stage IIIA-IIIB uterine cervical cancer were reviewed between 1995 and 2010. Tumor samples were obtained by biopsy prior to NAC. The patients were separated into two groups. One group comprised of the patients in which NAC was effective, surgery and radiotherapy were performed (NAC+OP+R group; n=35), and the second group contained patients in which NAC was ineffective and radiation therapy was performed (NAC+R group; n=27). SIRT1 and p53 expression was assessed immunohistochemically in paraffin-embedded sections. SIRT1 expression was significantly higher in the NAC+R compared to the NAC+OP+R group (P<0.001), as was p53 expression (P=0.001). The overall survival time was significantly longer in the NAC+OP+R compared to the NAC+R group (P=0.001). Following the division of patients into two groups based on SIRT1 level, low (weighted score ≤4, n=30), and high level (weighted score ≥6, n=32) groups, the former group was significantly more sensitive to NAC (P<0.001). Collectively, these results indicate that SIRT1 expression may predict the efficacy of NAC as a treatment for locally advanced uterine cervical cancer.

Phenotypic features with p53 alterations related to human papillomavirus and prognostic evaluation in cervical cancer

Cervical cancer is one of the most common tumor affecting women worldwide. Human papillomavirus (HPV) was found to have a causal relationship with cervical cancer and its precursors. The interaction between HPV E6 protein and p53 was identified in in vitro studies. The aim of the study was to evaluate the prevalence of p53 alterations related to HPV infection and the prognostic significance of p53 alterations in cervical cancer. Studies were identified by a MEDLINE search, and all relevant articles were retrieved from 1991 to March 2004. The prevalence of p53 mutations is a rare event in cervical cancer. The correlation between p53 mutations and HPV or prognosis is controversial. Loss of heterozygosity (LOH) of p53 is more commonly found in cervical cancer and is related with the prognosis of this disease. There is no significant correlation between p53 polymorphism and development of cervical cancer. The p53 mutations were not commonly found in cervical cancer. LOH of p53 may contribute to the progression of this malignancy. p53 polymorphism failed to be an independent prognostic factor in predicting the outcome of patients with cervical cancer. Further, epidemiologic surveys should be undertaken in larger populations and in different geographical regions.

Integrated human papillomavirus types 52 and 58 are infrequently found in cervical cancer, and high viral loads predict risk of cervical cancer

OBJECTIVE

The aim of this prospective study was to analyze whether integration or high viral loads of human papillomavirus (HPV) is essential for malignant transformation of HPV types 52 and 58 as well as types 16 and 18.

METHODS

Cervical swabs from 178 consecutive patients, including 81 with invasive cervical cancers and 97 with cervical intraepithelial neoplasias (CIN) II-III, were collected and examined to determine the physical status and viral load of HPV types 16, 18, 52 and 58 DNA using genechip and real-time PCR (polymerase chain reaction) analysis.

RESULTS

In cervical cancer patients, the integrated form of HPV 52 and 58 DNA was found in 25.0% and 12.5% of swabs, respectively; while HPV16 and 18 DNA was found in 82.6% and 100% of swabs, respectively (P < 0.01, for pair-wise comparison of types 16, 18 versus types 52, 58). The viral loads reflected by the amount of E6 for HPV 16, 18, or 52 were significantly increased in invasive cervical cancer compared to CINII-III (P = 0.022 for type 16, P = 0.003 for type18, and P = 0.001 for type 52, respectively). Area under the receiver operating characteristic (ROC) curve for cervical cancer versus CIN II-III was 73.8%, 92.9%, and 88.5% for HPV 16, 18, and 52, respectively, indicating that real-time PCR had good diagnostic value in differentiating cervical cancer from CIN II-III.

CONCLUSIONS

Infrequent integration of HPV 52 and 58 DNA in cervical cancer suggests that it is not prerequisite for progression to cervical cancer. High viral loads (E6) of HPV 16, 18, and 52 DNA may be predictive of the transition of CIN II-III to cervical cancer. Our results indicate that both viral DNA physical status and viral loads of HPV are important factors in the carcinogenesis of different HPV types.

HPV 16 detection in cervical lesions, physical state of viral DNA and changes in p53 gene

CONTEXT

Persistent infection with high risk human papillomavirus (HPV) has been linked to cervical carcinoma. Integration of viral DNA into host cell DNA is essential for this cancer development, promoting disruption of the HPV E2 gene, thus leading to unregulated increases in E6 and E7 proteins and inactivating the products of p53 and Rb tumor suppressor genes.

OBJECTIVE

To investigate HPV 16 infection in cervical lesions, physical state of viral DNA and p53 gene alterations in a group of women attending a public health service.

DESIGN

Prospective, non-controlled, transversal study.

SETTING

Gynecological clinic of the School of Medicine, Universidade Federal Fluminense.

SAMPLE

43 consecutive patients with cervical lesions referred to our service.

MAIN MEASUREMENTS

Cases were classified via cytology/histology as normal, HPV infection, condyloma, low-grade squamous intraepithelial lesion (LSIL), high-grade squamous intraepithelial lesion (HSIL) and carcinoma. HPV infection was studied via polymerase chain reaction (PCR) using two PCR primer sets, to determine DNA integration. p53 gene changes were investigated by single-strand conformation polymorphism (SSCP) analysis.

RESULTS

One normal case, 7 HPV infections, 6 condylomas, 7 LSIL, 14 HSIL and 8 cancers were found, with 95% positive for HPV genome when tested using both L1 and E6 primers. HPV 16 was most prevalent (73.1%). HPV 16 DNA was integrated within the host genome in 3 LSIL. One LSIL progressed to HSIL by 13 months after first diagnosis. Among HPV 16-positive HSIL cases, 50% contained integrated viral DNA. HPV 16 E2 gene disruption was seen in 7 cancers (87.5%). Only smal-cell carcinoma showed intact HPV 16 E2 gene. Abnormal p53 bands detected by PCR/SSCP were observed in 4 cases: 2 squamous carcinoma with parametrium (exon 8) and two cervical intraepithelial neoplasia (CIN) III (exons 5 and 7). All cases presented HPV 16 E2 gene loss.

CONCLUSIONS

The sample had a high rate of high-risk HPV detected in benign and malignant lesions; high cervical cancer burden; HPV 16 DNA integration in all except one case of cancer; p53 gene changes in CIN III and in invasive cancer cases associated with DNA integration.

Evaluation of p53 and Bcl-2 expression as prognostic markers in invasive cervical carcinoma stage IIb/III patients treated by radiotherapy

OBJECTIVE

The objective was to evaluate the immunohistochemical expression of p53 and Bcl-2 proteins as prognostic markers in locally advanced [FIGO Stage IIb/III] invasive squamous cell carcinoma of the uterine cervix. It was also our aim to determine if they had any relationship to each other and to the pretreatment levels of apoptosis determined morphologically.

METHODS

Seventy-six consecutive cases of invasive squamous cell carcinoma of the cervix diagnosed in 1995 were analyzed retrospectively for the apoptotic index and p53 and Bcl-2 expression determined immunohistochemically and correlated to the patient outcome at the end of a 5-year follow-up period.

RESULTS

The overall cumulative 5-year survival was 52.63%. p53 immunoreactivity was seen in 53.9% cases with variable levels of expression. By univariate analysis, p53 positivity correlated with poor survival [chi-square P = 0.029; log-rank test P = 0.0468] but not upon multivariate analysis. The apoptotic index which ranged from 0 to 40 and Bcl-2 expression seen in 38.1% cases showed no correlation to survival. Neither p53 nor Bcl-2 expression correlated with the apoptotic index or with each other. Seven cases with the immunophenotype p53-/Bcl-2+ had an excellent survival.

CONCLUSIONS

Neither p53 nor Bcl-2 expression are independent predictors of prognosis in locally advanced cervical squamous cancers. However, evaluation of their combined expression may affect clinical outcome and needs further investigation.

P53 expression as a predictor of recurrence in cervical squamous cell carcinoma

P53 protein function is frequently down-regulated in cervical cancer by complexing with human papillomavirus (HPV) E6 protein, leading to degradation of p53, genomic instability, and mutations. Results are controversial, however, on the prognostic value of p53 protein expression in cervical cancer. In this study, a cohort of 220 Brazilian women with FIGO stage IB-III cervical squamous cell carcinoma (SCC), followed for 5 years, was analyzed for p53 protein expression using immunohistochemistry. The disease-free survival (DFS) and relapse rate were analyzed using univariate (Kaplan-Meier) and multivariable (Cox's proportional hazards model) survival analyses. P53 protein expression was detected in 35% of the patients, including 21% in stage I, 28% in stage II and 51% in stage III of disease. Of 220 women, only 116 completed one of the treatment options standardized by FIGO within 120 days. There was a higher risk of relapse in stage II and III disease, that was not modified by p53 positivity; HR 3.0 (1.3-6.5) to stage II and HR 4.0 (1.9-8.5) to stage III. The multivariate analysis evidenced that p53 expression is not an independent factor exceeding the power of FIGO stage as the single most important determinant of the hazards for disease relapse.

p53 in surgically treated and pathologically staged cervical cancer: correlation with local tumor progression, but not with lymphatic spread

There is only limited information about the prognostic value of p53 immunostaining in cervical cancer. The purpose of this study was to assess the clinical significance of p53 and prognosis in operatively treated cervical carcinoma. A hundred and fourteen primary surgically treated cervical carcinomas (CX) were obtained from the so called Wertheim Archive in the Department of Obstetrics and Gynecology at the University of Leipzig. These included 105 squamous cell cancer (SCC) and nine adenocarcinomas (AC). No cases received neoadjuvant therapy. For immunohistochemical analysis, the cases were tested with the monoclonal antibody DO-7 (DAKO Diagnostics, Denmark). Two hundred tumor cell nuclei were counted for positive nuclear immunostaining, regardless of staining intensity. Cases were stated as positive when a minimum of 10% nuclei showed positive staining. Fresh frozen tissue was available from 21 CX for p53-mutation analysis (exons 4-9) using PCR-based amplification and SSCP-analysis. Of the squamous cell cancers (SCC), 63.8% showed positive nuclear p53-immunostaining; adenocarcinomas (AC) were completely negative (P = 0.0000, Chi2-test). Stage-by-stage analysis revealed no differences in p53-expression. However, combining pT1b- and pT2-cases, the difference in positive immunostaining reached statistical significance (44.4% vs. 71.7%; P = 0.007). There were no differences in p53-reactivity regarding the presence of pelvic lymph node metastases, tumor grading, relapse-free survival and tumor recurrence. In addition, only 5% of CX with positive p53-immunostaining showed genomic alterations in mutational analysis. p53-immunoreactivity showed significant correlation with local tumor progression but not with lymphatic spread, lacking any prognostic impact in surgically treated cervical cancer. There is no correlation of p53-immunostaining with the occurrence of p53-gene mutations in cervical cancer.

Analysis of the p53 gene and papillomavirus detection in smears from cervical lesions

CONTEXT

Alterations of the p53 tumor suppressor gene are correlated with a critical step in the development of many human cancers. The tumor suppressor gene functions include regulation of the cell cycle and the cellular response to DNA damage, initiation of DNA repair and replication, induction of apoptosis and promotion of cell differentiation.

CASE REPORT

Smears from ten cases of cervical lesions were analyzed for status of exons 5-8 of the p53 gene using PCR/SSCP. HPV infection was also screened by the PCR method using two PCR primer sets. Changes in the p53 gene were observed in a case of squamous carcinoma and a case of asymptomatic cervical intraepithelial neoplasia grade III (CIN III). High-risk HPV was detected in both cases showing that HPV infection and p53 mutation are not exclusive events.

Proto-oncogenes and p53 protein expression in normal cervical stratified squamous epithelium and cervical intra-epithelial neoplasia

The aim of this study was to study the protein expression of six proto-oncogenes (epidermal growth factor receptor (EGFR), c-fms, c-myc, c-kit, c-erbB-2 and pan-ras) and one tumour suppressor gene (TP53), by immunohistochemical staining of normal cervical stratified squamous epithelium and cervical intra-epithelial neoplasia (CIN). Paraffin sections of 45 normal cervical specimens, 38 CIN grade one (CIN1), 37 CIN2 and 43 CIN3 were studied. An immunohistochemical (IHC) score was derived from the intensity of staining and the percentages of cells stained. In normal cervical specimens, a higher IHC score was found with EGFR and c-fms in superficial (S), intermediate (I) and parabasal (PB) cells compared with basal cells. In contrast, a higher IHC score was found with c-erbB-2 in basal cells in normal cervical specimens. Dysplastic cells in CIN had a higher IHC score with c-myc and c-erbB-2 than normal S/I and PB cells. Dysplastic cells had a higher score with EGFR than normal basal cells. However, a higher IHC score with EGFR and c-fms was found in normal S/I cells than dysplastic cells. These findings suggested that EGFR and c-fms were activated in more differentiated normal cells but were less active in less differentiated normal basal cells. However, EGFR was reactivated in dysplastic cells. Meanwhile, c-erbB-2 was activated in less differentiated normal basal cells and dysplastic cells, and was less active in differentiated normal cells. c-myc was activated in dysplastic cells. c-fms was more active in more differentiated normal cells and was not activated in less differentiated or dysplastic cells. c-kit, pan-ras and TP53 were not activated in normal nor dysplastic cervical cells. These results suggest EGFR, c-erbB-2 and c-myc may be important proto-oncogenes in CIN and that antibodies or anti-genes targeted against them may alter the progress of CIN to invasive cancer.