Relationship between HPV typing and abnormality of G1 cell cycle regulators in cervical neoplasm

Successful pregnancy and delivery after HiPorfin photodynamic therapy for cervical high-grade squamous intraepithelial lesion

OBJECTIVE

The study analyzed HiPorfin-Photodynamic therapy (PDT) for young women with cervial high-grade squamous intraepithelial lesion (HSIL) and evaluated the impact of PDT on their pregnancy and delivery.

METHODS

Retrospective analysis of 4 patients (21-33 years old) were treated with HiPorfin® (2 mg/kg) PDT in 2019-2022. 1 patient suffered from cervical intraepithelial neoplasia (CIN)Ⅱ and 3 patients from CIN Ⅲ. 630 nm laser light irradiated the cervical surface and endocervical canal with light dose of 150 J/cm2 and 100-120 J/cm2 respectively.

RESULTS

The median observation time period was 40.5 months. Cure rate, HPV eradication rate and negative conversion rate of cytology were all 100.0 % at 3, 6 and 12 months. All cervical canal lesions completely turned negative. No recurrence occurred during the long-term follow-up period. None of patients suffered from infertility. Three patients delivered vaginally and one delivered by C-section to healthy infants at term.

CONCLUSION

HiPorfin® PDT for cervical HSIL was proved to be a safe method without adverse effects on female fertility and allowing these women to have healthy, full-term children.

Photodynamic therapy with HiPorfin for cervical squamous intraepithelial lesion at childbearing age

OBJECTIVE

To evaluate the clinical efficacy and safety of HiPorfin® photodynamic therapy (PDT) in the treatment of young women at reproductive age with high-grade squamous intraepithelial lesion (HSIL) of the cervix.

METHODS

Prospective study of 41 patients aged 28.8 ± 4.6 years old with cervical intraepithelial neoplasia (CIN) Ⅱ-Ⅲ at Peking University Shenzhen Hospital from March 2019 to January 2023. HiPorfin® (2 mg/kg) was infused intravenously, and 48-72 h later, 630-nm laser irradiation was performed in cervical canal and cervical surface with an irradiation dose of 100-120 J/cm2 and 150 J/cm2 respectively.

RESULTS

All 41 patients with no recurrence had been observed at least 12 months follow-up period after PDT. The number of nulliparous women was 30 (30/41, 73.2 %). CIN Ⅱ were 22 cases (22/41,53.7 %) and CIN Ⅲ were 19 cases (19/41,46.3 %). Complete response (CR) was in 95.5 % (21/22) patients with CIN Ⅱ and 78.9 % (15/19) patients with CIN Ⅲ at 6 months follow-up. Meanwhile, CR rate was 100.0 % (22/22) and 84.2 % (16/19) in CIN Ⅱ and CIN Ⅲ group respectively at 12 months. Pre-treatment, all patients (41/41,100 %) were Human papilloma virus (HPV) positive. HPV eradication rate was 63.4 % (26/41), 73.2 % (30/41) and 92.7 % (38/41) at 3, 6 and 12 months after PDT respectively. Before treatment, cytology ≥ atypical squamous cells of undetermined significance (ASCUS) was 78.0 % (32/41). Negative conversion ratio of cytology was 75.0 % (24/32), 90.6 % (29/32) and 100.0 % (32/32) at 3, 6 and 12 months after PDT respectively. There were no serious adverse effects in patients during and after PDT.

CONCLUSION

HiPorfin-PDT is a promising and organ-saving approach for cervical HSIL, which also eradicates HPV infection effectively and can be a beacon of hope for the young women with fertility preservation requirement.

Genotype prevalence and age distribution of human papillomavirus from infection to cervical cancer in Japanese women: A systematic review and meta-analysis

BACKGROUND

National HPV vaccination coverage in Japan is less than one percent of the eligible population and cervical cancer incidence and mortality are increasing. This systematic review and meta-analysis aimed to provide a comprehensive estimate of HPV genotype prevalence for Japan.

METHODS

English and Japanese databases were searched to March 2021 for research reporting HPV genotypes in cytology and histology samples from Japanese women. Summary estimates were calculated by disease stage from cytology only assessment - Normal, ASCUS, LSIL, HSIL and from histological assessment - CIN1, CIN2, CIN3/AIS, ICC (ICC-SCC, and ICC-ADC), and other. A random-effects meta-analysis was used to calculate summary prevalence estimates of any-HPV, high-risk (HR) and low-risk (LR) vaccine types, and vaccine genotypes (bivalent, quadrivalent, or nonavalent). This study was registered with PROSPERO: CRD42018117596.

RESULTS

A total of 57759 women with normal cytology, 1766 ASCUS, 3764 LSIL, 2017 HSIL, 3130 CIN1, 1219 CIN2, 869 CIN3/AIS, and 4306 ICC (which included 1032 ICC-SCC, and 638 ICC-ADC) were tested for HPV. The summary estimate of any-HPV genotype in women with normal cytology was 15·6% (95% CI: 12·3-19·4) and in invasive cervical cancer (ICC) was 85·6% (80·7-89·8). The prevalence of HR-HPV was 86·0% (95% CI: 73·9-94·9) for cytological cases of HSIL, 76·9% (52·1-94·7) for histological cases of CIN3/AIS, and 75·7% (68·0-82·6) for ICC. In women with ICC, the summary prevalence of bivalent vaccine genotypes was 58·5% (95% CI: 52·1-64·9), for quadrivalent genotypes was 58·6% (52·2-64·9) and for nonavalent genotypes was 71·5% (64·9-77·6), and of ICC cases that were HPV positive over 90% of infections are nonavalent vaccine preventable. There was considerable heterogeneity in all HPV summary estimates and for ICC, this heterogeneity was not explained by variability in study design, sample type, HPV assay type, or HPV DNA detection method, although studies published in the 1990s had lower prevalence estimates of any-HPV and HR HPV genotypes.

INTERPRETATIONS

HPV prevalence is high among Japanese women. The nonavalent vaccine is likely to have the greatest impact on reducing cervical cancer incidence and mortality in Japan.

Methylation as a critical epigenetic process during tumor progressions among Iranian population: an overview

Cancer is one of the main health challenges and leading causes of deaths in the world. Various environmental and genetic risk factors are associated with tumorigenesis. Epigenetic deregulations are also important risk factors during tumor progression which are reversible transcriptional alterations without any genomic changes. Various mechanisms are involved in epigenetic regulations such as DNA methylation, chromatin modifications, and noncoding RNAs. Cancer incidence and mortality have a growing trend during last decades among Iranian population which are significantly related to the late diagnosis. Therefore, it is required to prepare efficient molecular diagnostic panels for the early detection of cancer in this population. Promoter hyper methylation is frequently observed as an inhibitory molecular mechanism in various genes associated with DNA repair, cell cycle regulation, and apoptosis during tumor progression. Since aberrant promoter methylations have critical roles in early stages of neoplastic transformations, in present review we have summarized all of the aberrant methylations which have been reported during tumor progression among Iranian cancer patients. Aberrant promoter methylations are targetable and prepare novel therapeutic options for the personalized medicine in cancer patients. This review paves the way to introduce a non-invasive methylation specific panel of diagnostic markers for the early detection of cancer among Iranians.

Organoids of the Female Reproductive Tract: Innovative Tools to Study Desired to Unwelcome Processes

The pelviperineal organs of the female reproductive tract form an essential cornerstone of human procreation. The system comprises the ectodermal external genitalia, the Müllerian upper-vaginal, cervical, endometrial and oviductal derivatives, and the endodermal ovaries. Each of these organs presents with a unique course of biological development as well as of malignant degeneration. For many decades, various preclinical in vitro models have been employed to study female reproductive organ (patho-)biology, however, facing important shortcomings of limited expandability, loss of representativeness and inadequate translatability to the clinic. The recent emergence of 3D organoid models has propelled the field forward by generating powerful research tools that in vitro replicate healthy as well as diseased human tissues and are amenable to state-of-the-art experimental interventions. Here, we in detail review organoid modeling of the different female reproductive organs from healthy and tumorigenic backgrounds, and project perspectives for both scientists and clinicians.

Genetic and molecular bases of esophageal Cancer among Iranians: an update

Abstract

Background

Esophageal cancer is one of the leading causes of cancer related deaths among the Iranians. There is still a high ratio of mortality and low 5 years survival which are related to the late onset and diagnosis. Majority of patients refer for the treatment in advanced stages of tumor progression.

Main body

It is required to define an efficient local panel of diagnostic and prognostic markers for the Iranians. Indeed such efficient specific panel of markers will pave the way to decrease the mortality rate and increase the 5 years survival among the Iranian patients via the early diagnosis and targeted therapy.

Conclusion

in present review we have reported all of the molecular markers in different signaling pathways and cellular processes which have been assessed among the Iranian esophageal cancer patients until now.

Associations of P16INK4a promoter hypermethylation with squamous intra-epithelial lesion, cervical cancer and their clinicopathological features: a meta-analysis

To assess the associations of P16INK4a methylation status with low-grade squamous intra-epithelial lesion (LSIL), high-grade squamous intra-epithelial lesion (HSIL), cervical cancer (CC) and their clinicopathological features, a meta-analysis with 29 eligible studies was conducted. Pooled odds ratios (ORs) with their 95% confidence intervals (CIs) were estimated to assess the strength of the associations. Heterogeneity, sensitivity of pooled results and publication bias were also evaluated. Overall, there was an increasing trend of P16INK4a hypermethylation rates among LSIL (21.4%), HSIL (30.9%) and CC (35.0%) specimens. P16INK4a hypermethylation was significantly associated with the increased risk of LSIL, HSIL and CC, with the pooled ORs of 3.26 (95% CI: 1.86-5.71), 5.80 (95% CI: 3.80-8.84) and 12.17 (95% CI: 5.86-25.27), respectively. A significant association was also found between P16INK4a hypermethylation and smoking habit (OR = 3.88, 95% CI: 2.13-7.08). Taken together, meta-analysis results support P16INK4a hypermethylation as an epigenetic marker for the progression of cervical carcinogenesis.

Association between positive murine double minute 2 expression and clinicopathological characteristics of esophageal squamous cell carcinoma: a meta-analysis

The correlations of murine double minute 2 (MDM2) T309G and esophageal cancer were elucidated because the association between MDM2 expression states and clinicopathological parameters of esophageal squamous cell carcinoma (ESCC) is controversial. We conducted a meta-analysis on studies screened from PubMed, Web of Science, Embase, the Cochrane Library, and the Chinese Biomedical Literature Databases that were published before October 2014. All studies describing the association between MDM2 and ESCC were traced. Meta-analysis was performed using the STATA software (Stata Corp., College Station, TX, USA). A total of 9 studies with 707 cases and 324 controls were included. MDM2 expression was higher in ESCC than in normal esophageal epithelium (odds ratio [OR] 10.38, 95% confidence interval [CI] 6.42-16.78, P < 0.001). High MDM2 expression was associated with early primary tumor stage (T1/T2 vs. T3/T4, OR 0.59, 95% CI 0.38-0.92, P = 0.018) and increased risk of regional lymph node metastasis (N0 vs. N1, OR 1.66, 95% CI 1.03-2.67, P = 0.039). However, no relationship was observed between MDM2 expression and the risk of distant metastasis (OR = 2.09, 95% CI 1.00-4.36, P = 0.050), and MDM2 was not significantly correlated with TP53 expression (OR 1.22, 95% CI 0.53-2.77, P = 0.643). Our analysis suggests that MDM2 acts as a potent marker of early primary tumor stage but higher risk of regional lymph node metastasis in ESCC. However, because of the limited number of studies included, the result should be further clarified by well-designed prospective studies.

PTEN and p16 genes as epigenetic biomarkers in oral squamous cell carcinoma (OSCC): a study on south Indian population

Phosphatase and tensin homolog (PTEN) and p16INK4a (p16) genes are tumor suppressor genes, associated with epigenetic alterations. PTEN and p16 promoter hypermethylation is a major epigenetic silencing mechanism leading to cancer. The cooperation between PTEN and p16 in pathogenesis of cancers suggest that their combination might be considered as potential molecular marker for specific subgroups of patients. Hence, the present study aimed to investigate whether PTEN and p16 promoter methylations were involved in oral squamous cell carcinoma (OSCC) in south Indian subjects. DNA methylation quantitative analyses of the two candidate tumor suppressor genes PTEN and p16 were performed by methylation-specific polymerase chain reaction (MSP). Fifty OSCC biopsy samples and their corresponding non-malignant portions as controls were studied comparatively. The methylation status was correlated with the clinical manifestations. Twelve out of 50 patients (24 %) were found to be methylated for PTEN gene, whereas methylation of the p16 gene occurred in 19 out of 50 cases (38 %). A statistically significant result was obtained (P = <0.0001 and 0.017) for both PTEN and p16 genes. PTEN and p16 promoter methylation may be the main mechanism leading to the low expression of PTEN and p16 genes indicating the progress of tumor development. Our data suggest that a low PTEN and p16 expression due to methylation may contribute to the cancer progression and could be useful for prognosis of OSCC. Therefore, analysis of promoter methylation in such genes may provide a biomarker valuable for early detection of oral cancer.

HPV DNA genotyping and methylation of gene p16 INK4A in cervical LSIL

BACKGROUND

DNA methylation is the most important epigenetic change involved in the control of gene expression in human cells. Methylation of the p16(INK4a) gene occurs early in the development of cervical cancer. Low-grade squamous intraepithelial lesions (LSILs) are prevalent, and their behavior is variable.

OBJECTIVE

To identify the HPV DNA type, detect the methylation status of the p16(INK4A) gene, and analyze their association with the cytological evolution of LSIL over a period of two years.

METHODS

We conducted a cohort study with 40 participants. Cervical scrapings were collected for cytological and molecular analysis. HPV DNA detection and typing were performed by means of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Methylation-specific PCR was performed to detect methylation.

RESULTS

HPV DNA was detected in 87% of the cases, and type 16 was the most frequent type. Methylation was detected in 11% of the cases and did not exhibit a significant correlation with the HPV type. Unfavorable cytological evolution exhibited a significant association with the presence of methylation.

CONCLUSION

HPV 16 was the most frequently detected type of HPV in LSIL. Methylation of the p16(INK4A) gene was infrequent and occurred independent of the presence of HPV DNA. Methylation of the p16(INK4a) gene exhibited a significant correlation with persistence/progression of LSIL.

Pathogenic role of the eight probably/possibly carcinogenic HPV types 26, 53, 66, 67, 68, 70, 73 and 82 in cervical cancer

Eight HPV types (HPV26, 53, 66, 67, 68, 70, 73 and 82) that are phylogenetically closely related to 12 WHO-defined high-risk (HR) HPV have been rarely but consistently identified as single HPV infections in about 3% of cervical cancer (CxCa) tissues. Due to lack of biological data, these types are referred to as probable/possible (p) HR-HPV. To analyse their biological activity in direct comparison to HR-HPV types, we selected 55 formalin-fixed, paraffin-embedded (FFPE) CxCa tissues harbouring single pHR-HPV infections (2-13 cases per type) and 266 tissues harbouring single HR-HPV (7-40 cases per type) from a worldwide, retrospective, cross-sectional study. Single HPV infection was verified by two genotyping methods. Presence of type-specific spliced E6*I mRNA transcripts and expression of cellular proteins indicative of HPV transformation were assessed in all cases. In 55 CxCa tissues with pHR-HPV, E6*I mRNA expression was 100%; high p16(INK4a) , 98%; low pRb, 96%; low CyD1, 93%; and low p53, 84%. Compared to HPV16 tissues as a reference, individual frequencies of these five markers did not differ significantly, either for any of the eight pHR-HPV and the 11 other HR types individually or for the groups of pHR and HR types without HPV16. We conclude that the eight pHR-HPV types, when present as a single infection in CxCa, are biologically active and affect the same cellular pathways as any of the fully recognized carcinogenic HR-HPV types. Therefore we have provided molecular evidence of carcinogenicity for types currently classified as probably/possibly carcinogenic. Although this evidence is crucial for HPV-type carcinogenicity classification, per se it is not sufficient for inclusion of these HPV types into population-wide primary and secondary prevention programmes. Such decisions have to include careful estimation of effectiveness and cost-benefit analyses.

Biological evidence for a causal role of HPV16 in a small fraction of laryngeal squamous cell carcinoma

BACKGROUND

Human papillomavirus (HPV) is a causal factor in virtually all cervical and a subset of oropharyngeal squamous cell carcinoma (OP-SCC), whereas its role in laryngeal squamous cell carcinoma (L-SCC) is unclear.

METHODS

Formalin-fixed paraffin-embedded (N=154) and deep-frozen tissues (N=55) of 102 L-SCC patients were analysed for the presence of 51 mucosal HPV types. HPV DNA-positive (HPV DNA+) cases were analysed for E6*I mRNA transcripts of all high risk (HR)/probably/possibly (p)HR-HPV identified, and for HPV type 16 (HPV16) viral load. Expression of p16(INK4a), pRb, cyclin D1 and p53 was analysed by immunohistochemistry.

RESULTS

Ninety-two patients were valid in DNA analysis, of which 32 (35%) had at least one HPV DNA+ sample. Among the 29 single infections, 22 (76%) were HPV16, 2 (7%) HPV56 and 1 each (4%) HPV45, HPV53, HPV70, HPV11 and HPV42. Three cases harboured HPV16 with HPV33 (twice) or HPV45. Only 32% of HPV DNA+ findings were reproducible. Among HPV16 DNA+ L-SCC, 2 out of 23 (9%) had high viral loads, 5 out of 25 (21%) expressed E6*I mRNA and 3 out of 21 (14%) showed high p16(INK4a) and low pRb expression (all three HPV16 RNA-positive), immunohistochemical marker combination not identified in any other HPV DNA+ or HPV DNA-negative (HPV DNA-) L-SCC, respectively.

CONCLUSION

HPV type 16 has a causative role in a small subgroup of L-SCC (<5% in this German hospital series).

A comparative analysis of clinical and molecular factors with the stage of cervical cancer in a Brazilian cohort

Cell cycle protein expression plays an important role in the pathophysiology of cervical cancer. However, few studies have attempted to correlate the use of these biomarkers with the clinical progression of the tumor.

Effect of CYP1A1 MSPI polymorphism on the relationship between TP53 mutation and CDKN2A hypermethylation in non-small cell lung cancer

BACKGROUND AND AIMS

The molecular mechanisms of lung cancer susceptibility have not been fully understood. Although it has been described that germline polymorphisms are associated with either mutation or methylation of genes, the link between gene polymorphisms and gene-gene interactions has not been investigated. Therefore, we conducted this study to determine whether CYP1A1/GSTM1 polymorphisms can affect the relationship between TP53 mutation and CDKN2A hypermethylation in lung cancer.

METHODS

This study included 196 primary non-small cell lung cancer (NSCLC) patients. CYP1A1 MSPI and GSTM1 polymorphisms were characterized through PCR-RFLP on DNA isolated from peripheral lymphocytes. TP53 mutations of exons 5 through 9 and CDKN2A promoter hypermethylation in both cancer tissues and corresponding normal tissues were analyzed by direct sequencing and methylation-specific PCR (MSP) respectively.

RESULTS

TP53 mutation in the tumor was associated with squamous cell histology and CDKN2A methylation was associated with older age (≥60 years), heavy smoking (>30 pack-years), squamous cell histology and advanced stage (stage II-IV). After adjusting for age, sex, smoking degree, histology type and TNM stage, the correlation between TP53 mutation and CDKN2A methylation was significant in patients with CYP1A1 risk genotype (p = 0.038), but not in those with CYP1A1 homogeneity wild genotype (p = 0.151).

CONCLUSIONS

This may suggest that TP53 mutation and CDKN2A methylation specifically interact to promote lung tumorigenesis in subjects with CYP1A1 risk genotype but not in those with CYP1A1 wild-type homozygotes, implying different pathways for the development of lung carcinoma with respect to CYP1A1 polymorphism.

Human papillomavirus genotype attribution in invasive cervical cancer: a retrospective cross-sectional worldwide study

BACKGROUND

Knowledge about the distribution of human papillomavirus (HPV) genotypes in invasive cervical cancer is crucial to guide the introduction of prophylactic vaccines. We aimed to provide novel and comprehensive data about the worldwide genotype distribution in patients with invasive cervical cancer.

METHODS

Paraffin-embedded samples of histologically confirmed cases of invasive cervical cancer were collected from 38 countries in Europe, North America, central South America, Africa, Asia, and Oceania. Inclusion criteria were a pathological confirmation of a primary invasive cervical cancer of epithelial origin in the tissue sample selected for analysis of HPV DNA, and information about the year of diagnosis. HPV detection was done by use of PCR with SPF-10 broad-spectrum primers followed by DNA enzyme immunoassay and genotyping with a reverse hybridisation line probe assay. Sequence analysis was done to characterise HPV-positive samples with unknown HPV types. Data analyses included algorithms of multiple infections to estimate type-specific relative contributions.

FINDINGS

22,661 paraffin-embedded samples were obtained from 14,249 women. 10,575 cases of invasive cervical cancer were included in the study, and 8977 (85%) of these were positive for HPV DNA. The most common HPV types were 16, 18, 31, 33, 35, 45, 52, and 58 with a combined worldwide relative contribution of 8196 of 8977 (91%, 95% CI 90-92). HPV types 16 and 18 were detected in 6357 of 8977 of cases (71%, 70-72) of invasive cervical cancer. HPV types 16, 18, and 45 were detected in 443 of 470 cases (94%, 92-96) of cervical adenocarcinomas. Unknown HPV types that were identified with sequence analysis were 26, 30, 61, 67, 69, 82, and 91 in 103 (1%) of 8977 cases of invasive cervical cancer. Women with invasive cervical cancers related to HPV types 16, 18, or 45 presented at a younger mean age than did those with other HPV types (50·0 years [49·6-50·4], 48·2 years [47·3-49·2], 46·8 years [46·6-48·1], and 55·5 years [54·9-56·1], respectively).

INTERPRETATION

To our knowledge, this study is the largest assessment of HPV genotypes to date. HPV types 16, 18, 31, 33, 35, 45, 52, and 58 should be given priority when the cross-protective effects of current vaccines are assessed, and for formulation of recommendations for the use of second-generation polyvalent HPV vaccines. Our results also suggest that type-specific high-risk HPV-DNA-based screening tests and protocols should focus on HPV types 16, 18, and 45.

The presence of methylation of the p16INK4A gene and human papillomavirus in high-grade cervical squamous intraepithelial lesions

Methylation is a chemical modification in which a methyl group (CH3) is added to the cytosine in the promoter region of the gene. It involves a very frequent epigenetic event that is found in many human cancers. Currently, there is no consensus on whether methylation of the p16 gene could be used as a biomarker in cervical intraepithelial neoplasia. The authors studied the presence of methylation of the p16 gene and human papillomavirus (HPV) DNA, and a possible relationship between them in high-grade squamous intraepithelial lesions of the cervix. This case-control study analyzed 27 high-grade squamous intraepithelial lesion samples and 20 normal cytology samples. To detect p16 methylation, methylation-specific polymerase chain reaction was used, and for HPV DNA detection the polymerase chain reaction was performed by using MY09/MY11 and GP5+/GP6+ consensus primers. The presence of methylation of the promoter region of the p16INK4a gene was detected in 55.6% of the samples from the case group, whereas it was detected only in 20% of the samples from the control group (P=0.005). HPV DNA was found in 66.7% of the samples from the case group, whereas only 15% from the control group (P=0.0001). The relationship between the presence of methylation of the p16 gene and HPV DNA did not prove statistically significant in the case group (P=0.67) or the control group (P=0.51). In conclusion, the presence of methylation of the p16 gene constituted an occurrence that was early but independent of the presence of HPV DNA.

p16INK4a hypermethylation and p53, p16 and MDM2 protein expression in esophageal squamous cell carcinoma

BACKGROUND

Tumor suppressor genes p53 and p16INK4a and the proto-oncogene MDM2 are considered to be essential G1 cell cycle regulatory genes whose loss of function is associated with ESCC carcinogenesis. We assessed the aberrant methylation of the p16 gene and its impact on p16INK4a protein expression and correlations with p53 and MDM2 protein expressions in patients with ESCC in the Golestan province of northeastern Iran in which ESCC has the highest incidence of cancer, well above the world average.

METHODS

Cancerous tissues and the adjacent normal tissue obtained from 50 ESCC patients were assessed with Methylation-Specific-PCR to examine the methylation status of p16. The expression of p16, p53 and MDM2 proteins was detected by immunohistochemical staining.

RESULTS

Abnormal expression of p16 and p53, but not MDM2, was significantly higher in the tumoral tissue. p53 was concomitantly accumulated in ESCC tumor along with MDM2 overexpression and p16 negative expression. Aberrant methylation of the p16INK4a gene was detected in 31/50 (62%) of esophageal tumor samples, while two of the adjacent normal mucosa were methylated (P < 0.001). p16INK4a aberrant methylation was significantly associated with decreased p16 protein expression (P = 0.033), as well as the overexpression of p53 (P = 0.020).

CONCLUSIONS

p16 hypermethylation is the principal mechanism of p16 protein underexpression and plays an important role in ESCC development. It is associated with p53 protein overexpression and may influence the accumulation of abnormally expressed proteins in p53-MDM2 and p16-Rb pathways, suggesting a possible cross-talk of the involved pathways in ESCC development.

Effect of human papillomavirus on cell cycle-related proteins p16, Ki-67, Cyclin D1, p53, and ProEx C in precursor lesions of cervical carcinoma: a tissue microarray study

In-depth study of cell cycle proteins and human papillomavirus (HPV) genotyping can provide useful information about the malignant potential of precursor lesions of cervical carcinoma (CC). Immunostaining of cell cycle-related proteins (p16, cyclin D1, Ki-67, p53, and ProEx C) was evaluated using tissue microarrays, and HPV genotypes were identified in 144 cervical tissue specimens encompassing normal or benign epithelial lesions, low- and high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively), and CC. In addition, 14 cases with atypical immature metaplasia (AIM) were included to compare their immunohistochemical features with those of well-established precursor lesions. Expression of p16, Ki-67, and ProEx C was most associated with the severity of dysplasia. Positive expression of p16, Ki-67, and ProEx C and negative expression of p53 seem to be related to HPV-16 infection. AIM cases show an immunohistochemical pattern more similar to LSIL than to HSIL. Immunohistochemical assessment of cell cycle proteins may help to distinguish normal and benign conditions of the cervix from precursor lesions of CC.

Human papillomavirus E7 oncoprotein overrides the tumor suppressor activity of p21Cip1 in cervical carcinogenesis

The E7 oncoprotein of the high-risk human papillomaviruses (HPV) is thought to contribute to cervical carcinogenesis at least in part by abrogating cell cycle regulation. E7 can dysregulate the cell cycle through its interaction with several cellular proteins including the retinoblastoma suppressor protein pRb, as well as the cyclin-dependent kinase inhibitor p21(Cip1). Inactivation of pRb in cervical epithelia is not sufficient to explain the ability of E7 to cause cervical cancers in transgenic mice. In the current study, we focused on the role of p21(Cip1) in cervical cancer. Cervical disease was significantly increased in p21(-/-) mice compared with p21(+/+) mice, showing that p21(Cip1) can function as a tumor suppressor in this tissue. Importantly, the ability of E7 to induce cervical cancers was not significantly enhanced on the p21-null background, consistent with the hypothesis that the ability of E7 to inhibit p21(Cip1) contributes to its carcinogenic properties. Further supportive of this hypothesis, cervical carcinogenesis in mice expressing a mutant form of HPV-16 E7, E7(CVQ), which fails to inactivate p21(Cip1), was significantly reduced compared with that in K14E7(WT) mice expressing wild-type HPV-16 E7. However, K14E7(CVQ) mice still displayed heightened levels of cervical carcinogenesis compared with that in nontransgenic mice, indicating that activities of E7 besides its capacity to inactivate p21(Cip1) also contribute to cervical carcinogenesis. Taken together, we conclude that p21(Cip1) functions as a tumor suppressor in cervical carcinogenesis and that p21(Cip1) inactivation by HPV-16 E7 partially contributes to the contribution of E7 to cervical carcinogenesis.

DEK proto-oncogene expression interferes with the normal epithelial differentiation program

Overexpression of the DEK gene is associated with multiple human cancers, but its specific roles as a putative oncogene are not well defined. DEK transcription was previously shown to be induced by the high-risk human papillomavirus (HPV) E7 oncogene via E2F and Rb pathways. Transient DEK overexpression was able to inhibit both senescence and apoptosis in cultured cells. In at least the latter case, this mechanism involved the destabilization of p53 and the decreased expression of p53 target genes. We show here that DEK overexpression disrupts the normal differentiation program in a manner that is independent of either p53 or cell death. DEK expression was distinctly repressed upon the differentiation of cultured primary human keratinocytes, and stable DEK overexpression caused epidermal thickening in an organotypic raft model system. The observed hyperplasia involved a delay in keratinocyte differentiation toward a more undifferentiated state, and expansion of the basal cell compartment was due to increased proliferation, but not apoptosis. These phenotypes were accompanied by elevated p63 expression in the absence of p53 destabilization. In further support of bona fide oncogenic DEK activities, we report here up-regulated DEK protein levels in both human papilloma virus-positive hyperplastic murine skin and a subset of human squamous cell carcinomas. We suggest that DEK up-regulation may contribute to carcinoma development at least in part through increased proliferation and retardation of differentiation.

Human papillomavirus type distribution in women from Asia: a meta-analysis

The aim of this study was to determine human papillomavirus (HPV) type distribution in women with and without cervical neoplasia from Asia and to estimate the potential future impact of an HPV 16/18 prophylactic vaccine in this region. A meta-analysis was conducted including 79 studies using polymerase chain reaction to detect HPV types. A total of 5954, 1653, 958, and 16,803 women with invasive cervical cancer (ICC), high-grade squamous intraepithelial lesions (HSIL), low-grade squamous intraepithelial lesions (LSIL), and normal cytology or histology were included, respectively. Type-specific prevalence of HPV types 6, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 70, 73, and 82 were estimated and stratified by cervical lesion grade. Overall HPV prevalence was 85.9%, 81.0%, 72.9%, and 14.4%, respectively, in women with ICC, HSIL, LSIL, and normal cytology/histology. In ICC, HPV 16 was the predominant type (52.4%), followed by HPV 18, 58, 33, 52, 45, 31, and 35. The estimated HPV 16/18-positive fraction was 66.9%, 40.4%, 26.7%, and 3.3% in women with ICC, HSIL, LSIL, and normal cytology or histology, respectively. In ICC, the estimated HPV 16/18-positive fraction was about 70% in all Asian geographic regions, with the exception of Japan (51.3%). HPV 16/18 vaccines are estimated to provide about 67% protection against ICC in Asia. HPV 58 and 52 were among the five most common types in ICC in eastern and southeastern Asia but not in south central Asia. After HPV 16 and 18, the next most six common HPV types were 58, 33, 52, 45, 31, and 35 that accounted for additional 20% of cervical cancer cases in Asia. For optimal population coverage, these HPV carcinogenic types should be considered for second-generation HPV prophylactic vaccines.

Activation of AKT and nuclear accumulation of wild type TP53 and MDM2 in anal squamous cell carcinoma

Human papilloma virus (HPV) infection is considered as an important aetiological factor for anal squamous cell carcinoma (ASCC) but is not sufficient for tumour progression. This carcinoma is poorly understood at the molecular level. Using the largest cohort of cases to date we investigated the molecular mechanisms underlying ASCC development, in particular the roles of TP53, MDM2 and AKT. Viral infection in our cohort occurred at high frequency (73%, 94/128) with HPV16 accounting for the majority (86%, 81/94) of infected cases. Only 4% (5/119) of ASCCs showed TP53 (exons 5-8) mutations, but a high frequency (91%, 100/110) of nuclear protein expression of TP53 was observed. There was a significant association (p < 0.001) between nuclear accumulation of TP53 and MDM2 protein although no MDM2 mutations were found, and copy number was normal. Cellular accumulation of phosphorylated-AKT was observed in 66% (82/125) of ASCCs and an association demonstrated between nuclear accumulation of MDM2 and activated AKT (p < 0.001). We observed a high frequency of copy number gain at PIK3CA (47%), and some coding sequence mutations (4%). Amplification of PIK3CA was associated with presence of phosphorylated-AKT (p= 0.008). There was no association between virus infection and TP53 nuclear accumulation (p = 0.5). However, a significant association was found between infection and MDM2 nuclear staining, and between infection and activated AKT (p = 0.04, p = 0.01, respectively). We propose that activation of AKT, possibly through the PI3K-AKT pathway, is an important component of ASCC tumorigenesis that contributes to MDM2 and TP53 accumulation in the nucleus.

Senescence and apoptosis in carcinogenesis of cervical squamous carcinoma

Senescence and apoptosis are two key mechanisms that protect against cancer development. Many cell cycle regulators, such as p14(ARF), p15(INK4b) and p16(INK4a), are important in G1 cell cycle arrest and oncogene-induced senescence. The bcl-2 protein is one of the key components that control apoptosis, while the p53 protein plays key roles in both mechanisms. The genes of these key regulator proteins are often mutated or deleted in various malignancies. It is unknown how senescence and apoptosis are regulated in one of the most common tumors of the female genital tract, cervical squamous cell carcinoma (SCC). In this study the, expression of senescence, apoptosis and proliferation markers in normal cervical epithelium, cervical intraepithelial neoplasia (CIN) and SCC are characterized via immunohistochemical staining for p14(ARF), p15(INK4b), p16(INK4a), bcl-2, p53 and Ki-67 in tissue microarray blocks containing 20 samples each of normal cervix, moderate-to-severe cervical dysplasia (CIN II-III) and invasive SCC. Samples are derived from 60 total cases of cervical biopsies and cervical conizations. Results showed that the proliferation marker, Ki-67, is markedly increased, and the senescence markers, p15(INK4b), p16(INK4a) and p14(ARF) are overexpressed in both dysplasia and carcinoma. P53 immunostain is negative in all normal cervical tissue, and positive in dysplasia and carcinoma. Although the expression of bcl-2 is increased in dysplasia, this marker is negative in approximately half of SCC cases. These results suggest that some senescence pathways are activated and are still maintained in cervical dysplasia and carcinoma. However proliferation is increased and carcinogenesis is not thwarted, leading to eventual development of cervical cancer. Other mechanisms, such as those that account for the apparent overexpression of p53 and paradoxical loss of bcl-2 expression in some SCC cases, as well as additional senescence and apoptotic pathways, may play key roles carcinogenesis of cervical SCC.

Characteristics of vulvar squamous cell carcinoma in Japanese women

Although the presence of racial differences in vulvar squamous cell carcinomas has been suggested, fully analyzed data concerning such tumors in Japanese women have not been reported. A total of 21 vulvar squamous cell carcinomas of Japanese women who lived in north-east Japan, were studied with respect to histological subtype, HPV, p53 and p16(INK4a). The majority of tumors consisted of keratinizing and non-keratinizing types (16/21, 76%), all of which were negative for HPV. The remaining five tumors of basaloid, warty or verrucous types were positive for HPV. HPV-negative tumors showed a trend of greater accumulation of gene abnormalities, including p53 gene mutation, than HPV-positive ones. p16(INK4a) overexpression was shown to not always be a marker for vulvar squamous cell carcinoma in Japanese women with activated high-risk HPV.

The possible role of cell cycle regulators in multistep process of HPV-associated cervical carcinoma

Background

Human papillomavirus (HPV) 16 and 18 are associated with cervical carcinogenesis through an interaction between HPV oncogenic proteins and cell cycle regulatory genes. However, the exact pathogenetic mechanisms are not determined yet.

Methods

We investigated 43 invasive squamous cell carcinoma (ISCC), 38 CIN III, 11 CINII and 18 CINI for cyclin D1, cyclin E, CDK4, p53, mdm-2, p21^waf, p27, p16^INK4A, Rb and Ki-67 aberrations using immunohistochemistry and molecular techniques. Twenty samples of normal cervical tissues (NCT) were taken as a control.

Results

There was a significant increase in the expression of Ki-67, cyclin E, CDK4, p16^INK4A, Rb (p= 0.003, 0.001, 0.001, 0.01) and a significant decrease in p27^KIP1 from NCT to ISCC (p = 0.003). Increased cyclin D1, p21^waf, p53, mdm-2 expression, homozygous deletion (HZD) and promoter methylation (PM) of the Rb were detected in CINIII and ISCC only. On univariate analysis; tumor size, differentiation, lymph node status, FIGO stage, Ki- 67, cyclin D1, p53 and p27^KIP1 are significantly associated with reduced overall survival (OS) while on multivariate analysis; only FIGO stage, Ki-67, cyclin D1, p53 and p27^KIP1 were significant.

Conclusion

1) Aberrations involving p27^KIP1, cyclin E, CDK4, p16^INK4A are considered early events in HPV 16 and 18-associated cervical carcinoma, whereas cyclin D1 and p53 pathway abnormalities are considered late events. 2) Immunohistochemical tests for p16^INK4Aand cyclin E, could help in early diagnosis of cervical carcinoma. 3) Only FIGO stage p53, cyclin D1, p27^KIP1 and Ki-67 are independent prognostic factors that might help in predicting outcome of cervical cancer patients.

Immunohistochemical expression of p16(INK4A) in normal uterine cervix, nonneoplastic epithelial lesions, and low-grade squamous intraepithelial lesions

OBJECTIVES

In this study, the authors analyzed the immunoexpression of p16 in high-risk human papillomavirus DNA-negative normal and nonneoplastic cervical epithelia, in low-grade cervical intraepithelial neoplasia (CIN), high-grade CIN, and squamous cell carcinoma.

MATERIALS AND METHODS

A retrospective study, in which 58 normal cervical hysterectomy samples, 56 nonneoplastic cervical biopsies, 88 CIN 1, 33 CIN 2, 32 CIN 3, and 47 invasive squamous cell carcinoma biopsies, were evaluated for p16 immunoexpression. Human papillomavirus tests were also performed.

RESULTS

p16 immunohistochemistry seems to reveal possible different biological subgroups of lesions among morphologically similar mildly dysplastic cervical epithelia.

CONCLUSION

Distribution patterns of p16 protein might be useful to predict different outcomes in CIN 1.

A comparison of the clinical utility of p16(INK4a) immunolocalization with the presence of human papillomavirus by hybrid capture 2 for the detection of cervical dysplasia/neoplasia

BACKGROUND

Evidence suggests that overexpression of p16(INK4a) protein indicates infection and genomic integration of high-risk human papillomavirus (HR HPV) and predicts progression to cervical high-grade squamous intraepithelial lesions (HSILs) and carcinoma. The authors compared the ability of p16(INK4a) and HR HPV detection by Hybrid Capture 2 (HC2) to detect the presence of significant cervical disease. METHODS.: Four hundred ThinPrep specimens (100 each in 4 categories: 100 specimens that were negative for intraepithelial lesions, 100 specimens of atypical squamous cells of undetermined significance [ASC-US], 100 specimens of low-grade squamous intraepithelial lesions [LSILs], and 100 specimens of HSILs) were analyzed. p16(INK4a) protein was immunolocalized using a specific monoclonal antibody, and the detection of HR HPV in all 400 specimens was determined using HC2.

RESULTS

p16(INK4a) was found to be positive in 78% of HSIL specimens, 42% of LSIL specimens, and 36% of ASC-US specimens; whereas HC2 was positive in 92% of HSIL specimens, 81% of LSIL specimens, and 45% of ASC-US specimens. In the HSIL category, the sensitivity, which was calculated using Grade 2 or greater cervical intraepithelial neoplasia as the endpoint, was 78% (50 of 66 specimens) for p16(INK4a) and 91% (60 of 66 specimens) for HC2. For LSIL, the sensitivity was 75% (3 of 4 specimens) for p16(INK4a) and 100% (4 of 4 specimens) for HC2. In the ASC-US category, the sensitivity was 89% (8 of 9 specimens) for p16(INK4a) and 100% (9 of 9 specimens) for HC2. Overall, the sensitivity for HSIL was 92% for HC2 and 78% for p16(INK4a). The specificity for HC2 was 8.3% for HSIL, 16.9% for LSIL, and 48.7% for ASC-US; whereas the specificity for p16(INK4a) was 25% in HSIL, 59.1% in LSIL, and 68.4% in ASC-US. The overall specificity was 25% for HC2 and 56% for p16(INK4a).

CONCLUSIONS

Although both p16(INK4a) and HC2 may aid in the clinical management of patients with clinically significant lesions, HC2 was found to have greater sensitivity, and p16(INK4a) greater specificity. The labeling of normal cells and bacteria may preclude the use of p16(INK4a) in automated screening or nonmorphologic assays.

Methylation of p16INK4a is a non-rare event in cervical intraepithelial neoplasia

The cell cycle inhibitor, p16INK4a may be a useful surrogate biomarker of cervical intraepithelial neoplasia (CIN); however, there is currently no consensus of p16INK4a genetic alterations throughout the multiple step process of CIN. Our goal was to identify the methylation frequency of p16INK4a in each step of CIN that is associated with human papillomavirus (HPV) infection, using several different detection methods of p16INK4a methylation to correlate the data. The present study included a total of 43 patients, including 38 with CIN, and 5 normal patients. Three different methods were used to detect hypermethylation of CpG islands, methylation-specific PCR (MSP) amplification of different primer sets of M1, M2, and M3, pyrosequencing of each forward primer region, and immunohistochemistry of p16INK4a. Analysis of MSP showed that 20 of the 38 CIN patients (52.6%) revealed hypermethylation in at least 1 primer set of the p16INK4a promoter. A complete loss of p16INK4a protein expression was observed in 11 cases (28.9%). There was no observed association of methylation of the p16INK4a gene with either CIN grading (P=0.0698) or HPV status (P=0.2811): specifically 42.9% (3/7) was found in CIN 1, 57.1% (8/14) in CIN 2, and 52.9% (9/17) in CIN 3. In concordance with immunohistochemistry results, hypermethylation of the p16INK4a promoter was significantly correlated with a lack of p16 protein expression (P=0.0145). All positive peaks from pyrosequencing matched the MSP results, which ranged from 6.3% to 24.5%. In conclusion, p16INK4a gene silencing during CIN was not determined to be a particularly rare event; however, it does not correlate with either HPV status or CIN grading.

p16 expression in relation to human papillomavirus in anogenital lesions

Recent studies have revealed that cervical cancers associated with high-risk human papillomavirus (HPV) showed overexpression of the p16 protein, a cyclin-dependent kinase inhibitor. The expression of this cell cycle regulator in lesions of the anogenital region in association with HPV physical status (episomal or integrated) has not been studied at the present time. In this report, immunohistochemical analysis of p16 and HPV detection by in situ hybridization were performed on 110 formalin-fixed and paraffin-embedded samples of anogenital lesions. The results showed strong diffuse p16 staining in all integrated high-risk HPV-positive lesions, whereas most episomal HPV-positive lesions or HPV-negative lesions showed no p16 immunostaining. However, there were a few HPV-negative lesions or lesions with episomal HPV harboring p16 overexpression. On the other hand, some lesions were p16 negative while showing the presence of high-risk HPV in its episomal form. In conclusion, screening for p16 overexpression in cutaneomucous lesions of the anogenital region allowed good discrimination between HPV-integrated lesions and lesions harboring episomal HPV or no HPV. But p16 overexpression was not always predictive of the presence of high-risk HPV; moreover, absence of p16 immunostaining observed in some high-risk HPV lesions suggested that limiting the screening to p16 would exclude some patients harboring high-risk HPV from any follow-up.

p16INK4a Overexpression Independent of Human Papillomavirus Infection in Lobular Endocervical Glandular Hyperplasia

A high rate of human papillomavirus (HPV) infection has been reported in cervical cancer and precancerous lesions. Many studies also have shown that p16INK4a overexpression is of diagnostic value for high-risk HPV-related cervical cancer and precursors. Lobular endocervical glandular hyperplasia (LEGH) is a rare lesion of the uterine cervix. There is one report about HPV infection and few studies on p16INK4a expression in LEGH. Therefore, we 1) detected HPV infection and examined p16INK4a expression and 2) observed the relationship between HPV and p16INK4a overexpression in LEGH. The immunohistochemical expression of p16INK4a was studied in 24 cases of LEGH. HPV DNA was also evaluated in these cases using a polymerase chain reaction technique. Strong (++) p16INK4a immunoreactivity was observed in 10 (41.7%) of the 24 LEGH cases; a moderate (+) pattern was observed in 9 (37.5%) cases; a weak (+) pattern was observed in 2 (8.3%) cases; and the remaining 3 (12.5%) cases showed negative expression. Overall, p16INK4a overexpression was seen in 87.5% of the cases (21/24). HPV DNA was not detected in any of the 24 LEGH cases. These results suggest that p16INK4a overexpression is independent of HPV infection in LEGH.

p14ARF and p16INK4A, two products of the same gene, are differently expressed in cervical intraepithelial neoplasia

OBJECTIVE

To study the expression patterns of two different tumor suppressor proteins p16INK4A and p14ARF in cervical lesions. Both proteins are encoded by the same INK4A/ARF gene on chromosome 9p21. The expression patterns of these two proteins, both playing a central role in the cell cycle, were analyzed in detail in CIN, carcinomas, and normal epithelium to test the hypothesis that p16INK4A positive cells also demonstrate p14ARF expression.

METHODS

Serial tissue sections of 9 CIN1 lesions, 10 CIN2 lesions, 12 CIN3 lesions, and 7 carcinomas were stained with monoclonal antibodies against p16INK4A and p14ARF. The short fragment polymerase chain reaction hybridization line probe assay was used to detect HPV.

RESULTS

Normal epithelium was negative for both proteins. Marked immunoreactivity (++) for p16INK4A and p14ARF was observed in 5/7 carcinomas, 10/12 CIN3, and 1/10 CIN2 lesions and 0/9 CIN1 lesions. Simultaneous expression (+ or ++) was found in 19/22 CIN2/3 and not in CIN1 lesions. The fraction of p16INK4A-stained cells increased with CIN-grade. Overexpression of p14ARF was observed in a subpopulation of p16INK4A positive cells, and exclusively found in lesions infected with high-risk HPV. In two CIN3 lesions with early stromal invasion, p14ARF positivity was mainly found in the invasive cells. In carcinomas, all cells showed p16INK4A expression, whereas p14ARF was limited to the peripheral cells of the invasive tumor nests and individual migrating tumor cells.

CONCLUSIONS

Overexpression of p14ARF is limited to a fraction of the p16INK4A-expressing cells and therefore it is likely that p14ARF- and p16INK4A expression are not induced by the same mechanisms. Before expression of p14ARF can be linked to invasion or invasive phenotype, larger series of (micro-) invasive squamous lesions need to be studied.

Aberrant cell cycle regulation in cervical carcinoma

Carcinoma of the uterine cervix is one of the most common malignancies among women worldwide. Human papillomaviruses (HPV) have been identified as the major etiological factor in cervical carcinogenesis. However, the time lag between HPV infection and the diagnosis of cancer indicates that multiple steps, as well as multiple factors, may be necessary for the development of cervical cancer. The development and progression of cervical carcinoma have been shown to be dependent on various genetic and epigenetic events, especially alterations in the cell cycle checkpoint machinery. In mammalian cells, control of the cell cycle is regulated by the activity of cyclin-dependent kinases (CDKs) and their essential activating coenzymes, the cyclins. Generally, CDKs, cyclins, and CDK inhibitors function within several pathways, including the p16(INK4A)-cyclin D1-CDK4/6-pRb-E2F, p21(WAF1)- p27(KIP1)-cyclinE-CDK2, and p14(ARF)-MDM2-p53 pathways. The results from several studies showed aberrant regulation of several cell cycle proteins, such as cyclin D, cyclin E, p16(INK4A), p21(WAF1), and p27(KIP1), as characteristic features of HPV- infected and HPV E6/E7 oncogene-expressing cervical carcinomas and their precursors. These data suggested further that interactions of viral proteins with host cellular proteins, particularly cell cycle proteins, are involved in the activation or repression of cell cycle progression in cervical carcinogenesis.

p16INK4A expression in cervical premalignant and malignant lesions

p16INK4a is a cyclin-dependent kinase (CDK) inhibitor which decelerates cell cycle by inactivating CDKs that phosphorylate pRb. Human Papillomavirus persistent infection plays an important role on cervical carcinogenesis, mainly by the action of two viral oncoproteins, E6 and E7, which interact with p53 and pRb, respectively. Increasing expression of E6 and E7 in dysplastic cervical cells might thus be reflected by increased expression of p16INK4a. Recent studies revealed that p16INK4a expression could be a marker for dysplastic and neoplastic cervical cells. The aim of this study was to analyze p16INK4a expression in cervical preneoplastic and neoplastic lesions and correlate with lesion grade. Expression of p16INK4a was analyzed by immunohistochemistry. A total of 6 low-grade squamous intraepithelial lesion (LSIL), 21 high-grade squamous intraepithelial lesions (HSIL) and 27 cancer samples were studied. In HPV-positive cervical samples (n=48), p16INK4a expression was observed in 1 of 3 LSIL, in 18 of 19 HSIL and in all 26 cancer cases. These results are in accordance with the hypothesis that functional inactivation of pRb by HPV-E7 protein induces p16INK4a expression in cervical lesions. In our study, a statistically significant association was observed between cervical lesion grade and p16INK4a expression (P<0.001).

Photodynamic Therapy for Cervical Intraepithelial Neoplasia

OBJECTIVES

Photodynamic therapy (PDT) is a minimally invasive treatment for cervical intraepithelial neoplasia (CIN). We report the effectiveness of PDT in 105 cases of CIN.

METHODS

All patients received photofrin (PHE) 2 mg/kg intravenously and, 48-60 h later, phototherapy was performed using the Excimer dye laser or a YAG-OPO laser with an irradiation dose of 100 J/cm(2) using 630 nm wavelength.

RESULTS

Mild photosensitivity occurred in 48% (50/105) of patients. The complete response (CR) rate was 90% (94/105) at 3 months following treatment. In the remaining 11 patients, 5 patients had CIN1, 2 patients had CIN2, and 4 patients had mild cytologic findings. However, in 9 of these 11 patients, CR was achieved 6 months after PDT. In 69 patients, human papilloma virus (HPV) typing was performed before and after PDT therapy. Pre-treatment, 64 of 69 patients (93%), were HPV-positive including 30 cases of high-risk HPV (43%). Testing performed 3, 6 and 12 months following PDT revealed no HPV-DNA in 75% (52/69), 74% (48/65) and 72% (41/57) of patients. At present, the median follow-up period is 636 days (90-2,232 days). In 3 patients, recurrence requiring surgical treatment was identified at 646, 717 and 895 days after PDT.

CONCLUSIONS

PDT is an effective and minimally invasive treatment for CIN, which also appears to eradicate HPV infection.

Role of human papillomavirus in the carcinogenesis of squamous cell carcinoma and adenocarcinoma of the cervix

Human papillomavirus (HPV) infection is the most common sexually transmitted disease, with more than 80% of the population infected at some time in their life. In rare cases, this infection may lead to cervical cancer. Virtually all squamous cell carcinomas and the overwhelming majority of adenocarcinomas of the cervix are HPV positive. HPV integration in the genome will lead to inactivation of the p53 pathway and the Rb pathway. Integration is essential for the onset of cervical carcinogenesis, but is probably not sufficient for progression to invasive cervical cancers. It is likely that several cofactors, such as environmental, viral and host-related factors, are necessary for the development of cervical cancer. There are several similarities and differences between the two major histological types. This article will address the role of HPV in cervical carcinogenesis as well as the molecular biology involved in the process.