Identification of high-grade cervical dysplasia by the detection of p16INK4a in cell lysates obtained from cervical samples

Cervical Cancer Diagnosis: Insights into Biochemical Biomarkers and Imaging Techniques

Cervical malignancy is known as one of the important cancers which is originated from cervix. This malignancy has been observed in women infected with papillomavirus who had regular oral contraceptives, multiple pregnancies, and sexual relations. Early and fast cervical cancer diagnosis is known as two important aspects of cervical cancer therapy. Several investigations indicated that early and fast detection of cervical cancer could be associated with better treatment process and increasing survival rate of patients with this malignancy. Imaging techniques are very important diagnosis tools that could be employed for diagnosis and following responses to therapy in various cervical cancer stages. Multiple lines of evidence indicated that utilization of imaging techniques is related to some limitations (i.e. high cost, and invasive effects). Hence, it seems that along with using imaging techniques, finding and developing new biomarkers could be useful in the diagnosis and treatment of subjects with cervical cancer. Taken together, many studies showed that a variety of biomarkers including, several proteins, mRNAs, microRNAs, exosomes and polymorphisms might be introduced as prognostic, diagnostic and therapeutic biomarkers in cervical cancer therapy. In this review article, we highlighted imaging techniques as well as novel biomarkers for the diagnosis of cervical cancer.

Triaging abnormal cervical cancer screening tests using p16INK4a detection by ELISA on fresh cervical samples

PROBLEM

Cervical cancer screening strategies in the United States include cotesting (human papillomavirus (HPV) with cytology), primary HPV with genotyping and reflex cytology, and cytology alone. An ongoing challenge is the appropriate triage of patients to colposcopy to those at highest risk. We investigated whether incorporation of p16INK4a immunodetection by enzyme-linked immunosorbent assay (ELISA) on fresh cervical samples obtained at the time of screening could improve appropriate referral to colposcopy.

METHOD OF STUDY

A derivation group comprised of cervical swabs collected from subjects with high-grade dysplasia or cancer (positive control) and from subjects with negative screening history (negative control). Samples collected from colposcopy were used to evaluate the existing screening strategies individually and with incorporation of p16INK4a ELISA. Histology was used as the gold standard.

RESULTS

Among 163 subjects recruited, 138 were included. In the derivation group, mean p16INK4a level was 2.86 ng/mL (n = 31) and 0.58 ng/mL (n = 20) among positive and negative controls respectively (p = 0.002) with an area under the receiver operator characteristic curve of 0.79 (p < 0.001). Among colposcopy subjects, sensitivity/specificity for cotesting, primary HPV, and cytology were 94%/42%, 88%/45%, and 88%/49%, respectively. Incorporation of p16INK4a resulted in similar sensitivity and improved specificity (cotesting+p16 88%/58%, primary HPV+p16 88%/57%, cytology+p16 81%/62%; p = 0.23/p = 0.008) with decrease in colposcopy referrals by 15% to 22% (p = 0.01).

CONCLUSIONS

These results demonstrate the feasibility of quantifying p16INK4a by ELISA in fresh cervical samples, and its potential as an adjunct to existing screening strategies in the identification of high grade-dysplasia while reducing the number of colposcopic referrals.

HNRNPA1, a Splicing Regulator, Is an Effective Target Protein for Cervical Cancer Detection: Comparison With Conventional Tumor Markers

OBJECTIVE

Heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1), serine/arginine-rich splicing factor 1 (SRSF1), and SRSF3 are splicing regulators associated with oncogenesis. However, the alterations of SF proteins and their diagnostic values in cervical cancer are unclear. To apply SFs clinically, effective marker selection and characterization of the target organ properties are essential.

MATERIALS AND METHODS

We concurrently analyzed HNRNPA1, SRSF1, SRSF3, and the conventional tumor markers squamous cell carcinoma antigen (SCCA) and carcinoembryonic antigen (CEA) in cervical tissue samples (n = 127) using semiquantitative immunoblotting. In addition, we compared them with p16 (cyclin-dependent kinase inhibitor 2A [CDKN2A]), which has shown high diagnostic efficacy in immunohistochemical staining studies and has been proposed as a candidate protein for point-of-care screening biochemical tests of cervical neoplasia.

RESULTS

HNRNPA1, higher molecular weight forms of SRSF1 (SRSF1-HMws), SRSF3, CEA, and p16 levels were higher (P < 0.05) in cervical carcinoma tissue samples than in nontumoral cervical tissue samples. However, the levels of SRSF1-Total (sum of SRSF1-HMws and a lower molecular weight form of SRSF1) and SCCA, a commonly used cervical tumor marker, were not different between carcinoma and nontumoral tissue samples. In paired sample comparisons, HNRNPA1 (94%) showed the highest incidence of up-regulation (carcinoma/nontumor, >1.5) in cervical carcinoma, followed by p16 (84%), SRSF1-HMws (69%), SRSF3 (66%), CEA (66 %), SCCA (32%), and SRSF1-Total (31%). HNRNPA1 (92%) and p16 (91%) presented the two highest diagnostic accuracies for cervical carcinoma, which were superior to those of SRSF3 (75%), SRSF1-HMws (72%), CEA (72%), SCCA (59%), and SRSF1-Total (55%).

CONCLUSIONS

Our results identified that HNRNPA1 is the best diagnostic marker among the SFs and conventional markers given its excellent diagnostic efficacy for cervical carcinoma, and it has a p16-comparable diagnostic value. We suggest that HNRNPA1 is an additional effective target protein for developing cervical cancer detection tools.

Application of a time-resolved fluoroimmunoassay for detection of p16INK4a in cervix

OBJECTIVE

To establish a time-resolved fluoroimmunoassay (TRFIA) method to detect p16INK4a.

METHODS

119 cases of exfoliative cells following Thinprep cytologic test (TCT) test were selected for TRFIA and biopsy tissues of these patients according to TCT results were collected for immunohistochemical (IHC) staining.

RESULTS

There were 40 cases with cervicitis, 16 cases of cervical intraepithelial neoplasia grade 1 (CIN1), 15 cases of CIN2, 26 cases of CIN3, and 22 cases of squamous cell carcinoma (SCC). For each group, TCT results displaying above ASC-US were 7, 6, 12, 23, and 21 cases. IHC results were positive for 2, 13, 14, 26, and 21 cases, while the TRFIA results were positive for 5, 12, 13, 25, and 21 cases, respectively. The sensitivity and specificity were not significantly different between TCT and TRFIA test due to the limited cases. Significantly more CIN1 cases were positive by TRFIA, as compared with cervicitis (75.00% vs. 12.50%, χ²=21.116, p<0.001). Most (93.65%) CIN2/3 and SCC cases were positive for p16INK4a (higher than CIN1, χ²=4.877 and p=0.027).

CONCLUSION

Detecting p16INK4a protein by TRFIA is suitable to discriminate cervical dysplastic/neoplastic lesions from cervicitis. A commercial kit which created in the future might be a rapid, simple, and low-cost method to obtain objective results with an instrument automatically on a large scale.

Performance of p16INK4a ELISA as a primary cervical cancer screening test among a large cohort of HIV-infected women in western Kenya: a 2-year cross-sectional study

OBJECTIVE

A biomarker with increased specificity for cervical dysplasia compared with human papillomavirus (HPV) testing would be an attractive option for cervical cancer screening among HIV-infected women in resource-limited settings. p16(INK4a) has been explored as a biomarker for screening in general populations.

DESIGN

A 2-year cross-sectional study.

SETTING

2 large HIV primary care clinics in western Kenya.

PARTICIPANTS

1054 HIV-infected women in western Kenya undergoing cervical cancer screening as part of routine HIV care from October 2010 to November 2012.

INTERVENTIONS

Participants underwent p16(INK4a) specimen collection and colposcopy. Lesions with unsatisfactory colposcopy or suspicious for cervical intraepithelial neoplasia 2+ (CIN2+; including CIN2/3 or invasive cervical cancer) were biopsied. Following biopsy, disease status was determined by histopathological diagnosis.

PRIMARY AND SECONDARY OUTCOME MEASURES

We measured the sensitivity, specificity and predictive values of p16(INK4a) ELISA for CIN2+ detection among HIV-infected women and compared them to the test characteristics of current screening methods used in general as well as HIV-infected populations.

RESULTS

Average p16(INK4a) concentration in cervical samples was 37.4 U/mL. After colposcopically directed biopsy, 127 (12%) women were determined to have CIN2+. Receiver operating characteristic analysis showed an area under the curve of 0.664 for p16(INK4a) to detect biopsy-proven CIN2+. At a p16(INK4a) cut-off level of 9 U/mL, sensitivity, specificity, positive and negative predictive values were 89.0%, 22.9%, 13.6% and 93.8%, respectively. The overall p16(INK4a) positivity at a cut-off level of 9 U/mL was 828 (78.6%) women. There were 325 (30.8%) cases of correct p16(INK4a) prediction to detect or rule out CIN2+, and 729 (69.2%) cases of incorrect p16(INK4a) prediction.

CONCLUSIONS

p16(INK4a) ELISA did not perform well as a screening test for CIN2+ detection among HIV-infected women due to low specificity. Our study contributes to the ongoing search for a more specific alternative to HPV testing for CIN2+ detection.

Evaluation of p16INK4a immunostaining for the detection of high-grade changes in cervical cytology

Since its introduction in Australia in 2007, the human papillomavirus (HPV) vaccine has led to a markedly lower prevalence of vaccine targeted HPV genotype infections as well as HPV disease including genital warts and histologically confirmed high-grade (HG) cervical abnormalities. To increase the ability to identify abnormal cells in lower prevalence, adjunct markers can be incorporated to improve the sensitivity and specificity of cytology test. One such marker is p16(p16), which is detectable in cells expressing the E7 oncogene encoded by high-risk HPVs (HR-HPV). In this study, the sensitivity and specificity of p16 immunostaining in detection of underlying HG lesions was evaluated in a cohort of 454 women undergoing surgical treatment for biopsy proven cervical dysplasia. Overall, p16 positive cells were detected in 321 (71%) of cytology preparations evaluated. Comparison of p16 staining on cytological preparations to histology diagnosis available on 212 patients, showed 26 (54%), 41 (78%) and 80 (90%) of cytology preparations to be p16 positive in women with CIN1, CIN2 and CIN3, respectively (p < 0.005). HPV16 and 18 were the most prevalent genotypes in HG lesions and were highly correlated with p16 staining. p16 staining provides an additional marker which can assist in better detecting underlying HG lesion in cytology smears with low disease prevalence.

Mitosis is a source of potential markers for screening and survival and therapeutic targets in cervical cancer

The effect of preventive human papillomavirus (HPV) vaccination on the reduction of the cervical cancer (CC) burden will not be known for 30 years. Therefore, it's still necessary to improve the procedures for CC screening and treatment. The objective of this study was to identify and characterize cellular targets that could be considered potential markers for screening or therapeutic targets. A pyramidal strategy was used. Initially the expression of 8,638 genes was compared between 43 HPV16-positive CCs and 12 healthy cervical epitheliums using microarrays. A total of 997 genes were deregulated, and 21 genes that showed the greatest deregulation were validated using qRT-PCR. The 6 most upregulated genes (CCNB2, CDC20, PRC1, SYCP2, NUSAP1, CDKN3) belong to the mitosis pathway. They were further explored in 29 low-grade cervical intraepithelial neoplasias (CIN1) and 21 high-grade CIN (CIN2/3) to investigate whether they could differentiate CC and CIN2/3 (CIN2+) from CIN1 and controls. CCNB2, PRC1, and SYCP2 were mostly associated with CC and CDC20, NUSAP1, and CDKN3 were also associated with CIN2/3. The sensitivity and specificity of CDKN3 and NUSAP1 to detect CIN2+ was approximately 90%. The proteins encoded by all 6 genes were shown upregulated in CC by immunohistochemistry. The association of these markers with survival was investigated in 42 CC patients followed up for at least 42 months. Only CDKN3 was associated with poor survival and it was independent from clinical stage (HR = 5.9, 95%CI = 1.4-23.8, p = 0.01). CDKN3 and NUSAP1 may be potential targets for the development of screening methods. Nevertheless, further studies with larger samples are needed to define the optimal sensitivity and specificity. Inhibition of mitosis is a well-known strategy to combat cancers. Therefore, CDKN3 may be not only a screening and survival marker but a potential therapeutic target in CC. However, whether it's indispensable for tumor growth remains to be demonstrated.

E4 antibodies facilitate detection and type-assignment of active HPV infection in cervical disease

High-risk human papillomavirus (HPV) infections are the cause of nearly all cases of cervical cancer. Although the detection of HPV DNA has proved useful in cervical diagnosis, it does not necessarily predict disease presence or severity, and cannot conclusively identify the causative type when multiple HPVs are present. Such limitations may be addressed using complementary approaches such as cytology, laser capture microscopy, and/or the use of infection biomarkers. One such infection biomarker is the HPV E4 protein, which is expressed at high level in cells that are supporting (or have supported) viral genome amplification. Its distribution in lesions has suggested a role in disease staging. Here we have examined whether type-specific E4 antibodies may also allow the identification and/or confirmation of causal HPV-type. To do this, type-specific polyclonal and monoclonal antibodies against three E4 proteins (HPV-16, -18, and -58) were generated and validated by ELISA and western blotting, and by immunohistochemistry (IHC) staining of epithelial rafts containing these individual HPV types. Type-specific detection of HPV and its associated disease was subsequently examined using formalin-fixed paraffin-embedded cervical intra-epithelial neoplasias (CIN, (n = 247)) and normal controls (n = 28). All koilocytotic CIN1 lesions showed type-specific E4 expression of their respective HPV types. Differences were noted amongst E4 expression patterns in CIN3. HPV-18 E4 was not detected in any of the 6 HPV-18 DNA-positive CIN3 lesions examined, whereas in HPV-16 and -58 CIN3, 28/37 (76%) and 5/9 (55.6%) expressed E4 respectively, usually in regions of epithelial differentiation. Our results demonstrate that type-specific E4 antibodies can be used to help establish causality, as may be required when multiple HPV types are detected. The unique characteristics of the E4 biomarker suggest a role in diagnosis and patient management particularly when used in combination.

High-risk human papillomavirus (hrHPV) E6/E7 mRNA testing by PreTect HPV-Proofer for detection of cervical high-grade intraepithelial neoplasia and cancer among hrHPV DNA-positive women with normal cytology

Our aim was to investigate whether high-risk HPV (hrHPV) mRNA detection by PreTect HPV-Proofer can be used to stratify hrHPV DNA-positive women of different cytology classes for risk of high-grade cervical intraepithelial neoplasia or worse (cervical precancer or cancer, i.e., cervical intraepithelial neoplasia grade 2 or higher [≥ CIN2]). A total of 375 women participating in population-based screening, with a GP5+/6+-PCR hrHPV DNA-positive cervical scrape with normal cytology (n = 202), borderline or mild dyskaryosis (BMD) (n = 88), or moderate dyskaryosis or worse (>BMD) (n = 85), were enrolled. Cervical scrapes were additionally subjected to HPV16/18/31/33/45 E6/E7 mRNA analysis by PreTect HPV-Proofer (mRNA test). Referral and follow-up policies were based on cytology, hrHPV DNA, and mRNA testing. The primary study endpoint was the number of ≥CIN2 detected within 3 years of follow-up. The mRNA positivity increased with the severity of cytological abnormality, ranging from 32% (64/202) in hrHPV DNA-positive women with normal cytology to 47% (41/88) in BMD and 68% (58/85) in >BMD groups (P < 0.01). Women with ≥ CIN2 were more likely to test positive by mRNA test (63%) than women without evidence of ≥ CIN2 (32%; P < 0.01). A positive mRNA test result conferred an increased ≥ CIN2 risk in hrHPV DNA-positive women with normal cytology, i.e., 0.55 (95% confidence interval [95% CI], 0.34 to 0.76) in mRNA-positive versus 0.20 (95% CI, 0.07 to 0.33) in mRNA-negative women. In hrHPV DNA-positive women with BMD or >BMD, the result of the mRNA test did not influence the ≥ CIN2 risk. In conclusion, mRNA testing by PreTect HPV-Proofer might be of value to select hrHPV DNA-positive women with normal cytology in need of immediate referral for colposcopy.

Identification and validation of genes involved in cervical tumourigenesis

Background

Cervical cancer is the most common cancer among Indian women. This cancer has well defined pre-cancerous stages and evolves over 10-15 years or more. This study was undertaken to identify differentially expressed genes between normal, dysplastic and invasive cervical cancer.

Materials and methods

A total of 28 invasive cervical cancers, 4 CIN3/CIS, 4 CIN1/CIN2 and 5 Normal cervix samples were studied. We have used microarray technique followed by validation of the significant genes by relative quantitation using Taqman Low Density Array Real Time PCR. Immunohistochemistry was used to study the protein expression of MMP3, UBE2C and p16 in normal, dysplasia and cancers of the cervix. The effect of a dominant negative UBE2C on the growth of the SiHa cells was assessed using a MTT assay.

Results

Our study, for the first time, has identified 20 genes to be up-regulated and 14 down-regulated in cervical cancers and 5 up-regulated in CIN3. In addition, 26 genes identified by other studies, as to playing a role in cervical cancer, were also confirmed in our study. UBE2C, CCNB1, CCNB2, PLOD2, NUP210, MELK, CDC20 genes were overexpressed in tumours and in CIN3/CIS relative to both Normal and CIN1/CIN2, suggesting that they could have a role to play in the early phase of tumorigenesis. IL8, INDO, ISG15, ISG20, AGRN, DTXL, MMP1, MMP3, CCL18, TOP2A AND STAT1 were found to be upregulated in tumours. Using Immunohistochemistry, we showed over-expression of MMP3, UBE2C and p16 in cancers compared to normal cervical epithelium and varying grades of dysplasia. A dominant negative UBE2C was found to produce growth inhibition in SiHa cells, which over-expresses UBE2C 4 fold more than HEK293 cells.

Conclusions

Several novel genes were found to be differentially expressed in cervical cancer. MMP3, UBE2C and p16 protein overexpression in cervical cancers was confirmed by immunohistochemistry. These will need to be validated further in a larger series of samples. UBE2C could be evaluated further to assess its potential as a therapeutic target in cervical cancer.

Functional biomarkers in cervical precancer: an overview

Cervical cancer develops over a long time through precursor lesions that can be detected by cytological screening. Majority of these lesions regress spontaneously. Therefore, the challenge of cervical cancer screening is to detect the lesions that have a high risk of progression. Several promising biomarkers have been described that may improve screening of cervical cancer, but to date, new biomarkers have not been thoroughly validated in high-quality studies. The knowledge about human papillomavirus as a causative agent of cervical cancer has accumulated over the last decades has opened the possibility to improve the existing prevention strategies and screening practices. p16 has amply been applied on cytologic samples and has been shown to be a promising marker especially in identification of high-grade dysplasia. ProEx C, a replication marker, has also been recently shown to be a good marker for identification of high-grade dysplasia and has been used on cytologic samples. Proliferation markers such as MYC, Ki67, telomerase, MCM, topoisomerase 2A and 3q amplification by in situ hybridization technique are other methods being employed in identification of high-grade dysplasia. However, currently available data on most of the biomarkers does not warrant their routine use yet. This review highlights the major findings of previous studies on cervical cancer biomarkers.

[Human papillomaviruses in the pathogenesis of intraepithelial neoplasia (AIN) and carcinoma of the anus]

HPV infections have been implicated in the pathogenesis of anal cancers. The mode of infection and subsequent transformation resembles very much the pathogenesis of cervical and other HPV-associated cancers. The molecular dissection of individual steps required to achieve cellular transformation within an HPV-infected cell led to the identification of novel biomarkers that make it possible to identify HPV-transformed cells with substantially higher precision in comparison to conventional methods. Since effective antiretroviral therapy allows for possible long-term survival of HIV-infected individuals who are at very high risk to develop HPV-associated cancers in the anogenital tract, these new developments have become increasingly relevant for practicing dermatologists and proctologists. We here briefly review the basic concepts and some clinical applications of this recent research.

ELISA test to detect CDKN2A (p16(INK4a)) expression in exfoliative cells: a new screening tool for cervical cancer

BACKGROUND

The purpose of this study was to use an enzyme-linked immunosorbent assay (ELISA) to detect cyclin-dependent kinase inhibitor 2A (CDKN2A; also known as p16(INK4a)) in exfoliative cervical cells. CDKN2A is upregulated and considered as a surrogate marker for cervical intraepithelial neoplasia and cancer.

METHODS

Liquid-based ThinPrep((R)) cytologic test (TCT) and ELISA were performed on 1356 specimens collected prior to biopsy. A cotton swab was used to gather exfoliative cells. A sandwich ELISA was performed to measure the amount of solublized CDKN2A protein.

RESULTS

The sensitivity and specificity of the TCT for screening of cervical dysplasia and cancer were 82.93% and 88.11%, respectively. The sensitivity and specificity for measuring CDKN2A with ELISA to detect significant cervical disease were 87.80% and 92.43%, respectively. CDKN2A expression was correlated with the severity of cervical damage (r = 0.774; p < 0.001).

CONCLUSION

The sensitivity and specificity of detecting CDKN2A expression with ELISA in exfoliative cervical cells was superior to TCT (p = 0.023 and p < 0.001, respectively). These results suggest that detecting CDKN2A with ELISA has the potential to become a new screening method for cervical cancer.

Human papillomavirus mRNA and p16 detection as biomarkers for the improved diagnosis of cervical neoplasia

Human papillomavirus (HPV) infection of the genital tract is very common and normally follows a benign clinical course; however, in an unfortunate minority of infected individuals, it can cause disease that sometimes leads to cancer. It is accepted that HPV DNA testing has a role in the management of cervical disease both in a prevaccination and postvaccination era; however, to improve the specificity of this approach, there is a requirement to develop and validate tools/assays that can identify women at risk for progressive disease. There is evidence to suggest that detection of viral gene expression both directly and indirectly may constitute a more specific approach for delineating clinically significant infection compared with HPV DNA-based assays. HPV oncogene expression and evidence of its deregulation can be monitored through direct detection of viral mRNA transcripts or through detection of the cellular protein p16. For both approaches, commercial assays have been introduced and numerous studies have been conducted. The present article describes the scientific theory underpinning these approaches, their amenability to routine-diagnostic specimens/settings, and the clinical data that has been garnered through their application thus far. Currently, there is promising data indicating that HPV mRNA and p16 might play an important role in future cervical cancer screening scenarios. Still, large randomized studies are necessary to confirm the preliminary data.

METHODS

PubMed and OVID were interrogated with search terms "HPV RNA;" "HPV mRNA;" "HPV transcript-detection, testing, and methods;" "p16" AND "cervical cancer;" "p16" AND "CIN;" "p16" AND "histology"; "p16" AND "cytology;" "p16;" and "screening."

Early detection of cervical carcinomas: finding an overall approach

BACKGROUND

Infection with human papillomavirus (HPV) is a necessary, but not sufficient condition for the emergence of cervical cancer. Cervical cancer develops over several years through a series of precursor lesions that can be detected by cytological screening. The majority of these lesions, however, regress spontaneously. The challenge of cancer screening is to detect those patients who are at high risk of tumor progression.

METHODS

Selective literature review on cervical cancer screening in light of current guidelines and recommendations.

RESULTS AND CONCLUSION

Since the recently introduced vaccination against HPV does not provide full protection against cervical cancer, screening programs must continue. HPV vaccination and early detection of cervical carcinomas should be organized into a combined prevention program with systematic documentation, quality control, and active invitation to participate. It is assumed that the reduction in prevalence of precancerous lesions as a result of vaccination will have a negative impact on the efficiency of cytological early detection. Therefore, the existing screening procedures should be optimized and complemented by new techniques. Already available for screening is the detection of HPV DNA. Further promising biomarkers are currently being investigated in international studies, but no conclusions on their potential efficacy can yet be drawn.

Gene expression profiles in HPV-infected head and neck cancer

Epidemiological and laboratory evidence indicate that, in addition to tobacco and alcohol, human papillomaviruses (HPV) play an important aetiological role in a subset of head and neck squamous cell carcinoma (HNSCC). To evaluate the molecular pathogenesis of HPV-infected HNSCC, we compared gene expression patterns between HPV-positive and -negative HNSCC tumours using cDNA microarrays. Tumour tissue was collected from 42 histologically confirmed HNSCC patients from an inner-city area of New York. Total DNA and RNA were extracted and purified from frozen tumour samples and gene expression levels were compared to a universal human reference RNA standard using a 27 323 cDNA microarray chip. HPV detection and genotyping were performed using an MY09/11-PCR system and RT-PCR. HPV was detected in 29% of HNSCC tumours. Most harboured only HPV16 and expressed the HPV16-E6 oncogene. HPV prevalence was highest in pharyngeal tumours (45%). Gene expression patterns that differentiated HPV-positive from negative tumours were compared by supervised classification analysis, and a multiple-gene signature was found to predict HPV16 prevalence in primary HNSCC with a false discovery rate < 0.2. Focusing on never-smokers, we further identified a distinct subset of 123 genes that were specifically dysregulated in HPV16-positive HNSCC. Overexpressed genes in HPV-positive HNSCC tumours included the retinoblastoma-binding protein (p18), replication factor-C gene, and an E2F-dimerization partner transcription factor (TFDP2) that have also been found to be overexpressed in cervical cancer. An additional subset of genes involved in viral defence and immune response, including interleukins and interferon-induced proteins, was found to be down-regulated in HPV-positive tumours, supporting a characteristic and unique transcriptional profile in HPV-induced HNSCC.

Human papillomavirus and cervical cancer

Cervical cancer is the second most common cancer in women worldwide, and knowledge regarding its cause and pathogenesis is expanding rapidly. Persistent infection with one of about 15 genotypes of carcinogenic human papillomavirus (HPV) causes almost all cases. There are four major steps in cervical cancer development: infection of metaplastic epithelium at the cervical transformation zone, viral persistence, progression of persistently infected epithelium to cervical precancer, and invasion through the basement membrane of the epithelium. Infection is extremely common in young women in their first decade of sexual activity. Persistent infections and precancer are established, typically within 5-10 years, from less than 10% of new infections. Invasive cancer arises over many years, even decades, in a minority of women with precancer, with a peak or plateau in risk at about 35-55 years of age. Each genotype of HPV acts as an independent infection, with differing carcinogenic risks linked to evolutionary species. Our understanding has led to improved prevention and clinical management strategies, including improved screening tests and vaccines. The new HPV-oriented model of cervical carcinogenesis should gradually replace older morphological models based only on cytology and histology. If applied wisely, HPV-related technology can minimise the incidence of cervical cancer, and the morbidity and mortality it causes, even in low-resource settings.

Should LSIL with ASC-H (LSIL-H) in cervical smears be an independent category? A study on SurePath specimens with review of literature

Background

Cervical smears exhibiting unequivocal features of 'low grade squamous intraepithelial lesion' (LSIL) are occasionally also admixed with some cells suspicious for, but not diagnostic of, 'high grade squamous intraepithelial lesion' (HSIL). Only a few studies, mostly reported as abstracts, have evaluated this concurrence. In this study, we evaluate the current evidence that favors a distinct category for "LSIL, cannot exclude HSIL" (LSIL-H), and suggest a management algorithm based on combinations of current ASCCP guidelines for related interpretations.

Methods

We studied SurePath™ preparations of cervical specimens from various institutions during one year period. Cytohisto correlation was performed in cases with cervical biopsies submitted to our institution. The status of HPV DNA testing was also noted in some LSIL-H cases with biopsy results.

Results

Out of 77,979 cases 1,970 interpreted as LSIL (1,523), LSIL-H (146), 'atypical squamous cells, cannot exclude HSIL' (ASC-H) (109), and HSIL (192) were selected. Concurrent biopsy results were available in 40% (Total 792 cases: 557 LSIL, 88 LSIL-H, 38 ASCH, and 109 HSIL). Biopsy results were grouped into A. negative for dysplasia (ND), B. low grade (HPV, CIN1, CIN1 with HPV), and C. high grade (CIN 2 and above).

The positive predictive values for various biopsy results in relation to initial cytopathologic interpretation were: a. LSIL: (557 cases): ND 32% (179), low grade- 58% (323), high grade- 10% (55); b. LSIL-H: (88 cases): ND 24% (21), low grade- 43% (38), high grade- 33% (29); c. ASCH: (38 cases): ND 32% (12), low grade- 37% (14), high grade- 31% (12); d. HSIL (109 cases): ND 5% (6), low grade 26% (28), high grade 69% (75). The patterns of cervical biopsy results in cases reported as LSIL-H were compared with that observed in cases with LSIL, ASC-H, and HSIL.

94% (32 of 34) of LSIL-H were positive for high risk (HR) HPV, 1 was negative for HR HPV but positive for low risk (LR), and 1 LSIL-H was negative for HR and LR both.

Conclusion

LSIL-H overlapped with LSIL and ASC-H, but was distinct from HSIL. A management algorithm comparable to ASC-H and HSIL appears to be appropriate in LSIL-H cases.