Paola Alberizzi

Genetic pattern, histological structure, and cellular phenotype in early and advanced gastric cancers: Evidence for structure-related genetic subsets and for loss of glandular structure during progression of some tumors

Gastric cancer shows remarkable heterogeneity in histological pattern, cellular phenotype, and genotype. Tumor subsets identified by varying procedures have shown limited reciprocal correlation and have failed to provide a sound rationale for the characterization and classification of all tumors. Based on a case series of 130 gastric cancers that covered both early (70 cases) and advanced (60 cases) stages and that represented most histological types and structural patterns, this study investigated (1) microsatellite instability and p53 gene mutation by means of PCR-based molecular techniques and (2) p53 protein accumulation or tumor cell immunophenotype by means of immunoperoxidase procedures. It was found that microsatellite instability and p53 gene mutation involve two distinct subsets of both early and advanced-stage glandular (intestinal) cancer, and that, contrastingly, they leave purely diffuse cancers unaffected. Mixed cancers, namely, those in which glandular admixed with diffuse growths, showed scarce microsatellite instability at all stages, whereas prominent p53 gene mutation and p53 protein accumulation was limited to the advanced stage alone. No significant correlation was found between tumor cell immunophenotype and either genotype or histotype, although some correlation with particular structural patterns was detected. Comparison of intramucosal with invasive growths within any given tumor suggested that invasive cancers with diffuse-type growth arise in part from mucosal cancers of glandular or mixed structure through progressive loss of intercellular junctional systems. It is concluded that at least two genetically distinct subsets of glandular cancer, one with microsatellite instability and the other with p53 lesions, should be separated both from purely diffuse cancer and, at least in the advanced stage, from mixed cancer. Available evidence suggests distinct clinicopathologic profiles for such tumor entities.

Cervical infections by multiple human papillomavirus (HPV) genotypes: Prevalence and impact on the risk of precancerous epithelial lesions

A large proportion of human papillomavirus (HPV) infections is sustained by multiple genotypes. The effect of multiple infections on the risk of cervical intraepithelial neoplasia (CIN) and the potential efficacy of vaccine on these infections are controversial. We performed viral typing by SFP10‐LIPA on a consecutive series of 1,323 women undergoing colposcopy, 69% of whom had cervical biopsy, and correlated CIN severity with the type and number of HPVs. Overall prevalence of HPV‐DNA was 68.9%, 97.3% in CIN1, and 98.1% in CIN≥2. HPV positivity correlated with younger age (35.9 vs. 37.3 years, P = 0.026) and history of CIN (P < 0.001). Multiple types were detected in 44.2% of cases, including 63.1% CIN1 and 80.8% CIN≥2. Twenty‐three different types were detected, HPV‐16, 31 and 52 being the most frequent. Infections by HPV‐6, 11, 16, or 18 occurred in 59.4% of CIN1 and 71.3% of CIN≥2. Number of viral types and class of oncogenic risk were linearly correlated with CIN severity (P < 0.0001) by univariate and multivariate analyses controlling for age and history of CIN. The effect of the number of HPV types was maintained after exclusion from the model of infections by HPV‐6, 11, 16, and 18. Frequency, distribution, and clinical correlates of multiple HPV infections highlight the importance of assessing individual types in the management and the prediction of outcome of women with abnormal baseline cytology and point to potential limitations in current vaccine strategies. J. Med. Virol. 81:703–712, 2009

Clustering patterns of human papillomavirus genotypes in multiple infections.

Many human papillomavirus (HPV) infections are sustained by multiple viral genotypes whose effect on the risk of cervical intraepithelial neoplasia (CIN) is unknown. The study investigated whether specific HPV types or species may affect the likelihood of multiple infections and have a clustered distribution in a consecutive series of 681 women with a histological diagnosis of CIN. HPV typing was performed by the SPF(10)-LIPA assay; associations were evaluated by loglinear analysis of multiple contingency tables after stratification by age and CIN grade. HPV prevalence was 99.4% with a 72.1% rate of coinfection. The risk of coinfection was higher for types 6, 11, 16, 18, 31, 33, 51, 52, 56. Significant interactions were found for species A7-A9-A10, A6-A9 and A7-A10. Coinfection by types 31-35-56, 16-51-52, 16-18 and 51-52 was more frequent than expected. Interactions between viral species and HPV 16-18 were maintained among CIN1, whereas interactions of 16-51-52 and 31-51-56 were significant only in CIN> or =2. Interactions between species and types were lost among women younger than 32 years. Significant clustering of HPV types and species occurs among women with CIN. This has implications for the assessment of the oncogenic potential and the prevention of HPV infections.

Loss of heterozygosity at 18q21 region in gastric cancer involves a number of cancer-related genes and correlates with stage and histology, but lacks independent prognostic value.

Several studies support a role of 18q21 LOH, involving the DCC locus, in colorectal cancer progression; however, its contribution to the natural history of gastric cancer is less clear. Recently, a number of cancer‐related genes have been mapped in the 18q21 region, either centromeric or telomeric to DCC. This study searched for 18q21 LOH in 161 gastric cancers representative of all tumour stages and main histological types. To this purpose, seven highly polymorphic markers were used flanking the 18q21 band and spanning the entire region. Thirty‐four out of 147 (23.1%) informative cases showed LOH. In 27 of 34 cases (79%), LOH involved all the informative loci. The remaining seven cases showed LOH at more telomeric sites and retained heterozygosity at more centromeric markers, mostly those proximal to the DCC gene. A strong correlation between 18q21 LOH and level of gastric wall invasion, lymph node metastases, or stage was found in cohesive (glandular+solid) and mixed tumours, but not in diffuse cancers. Cox univariate and multivariate analysis showed that invasion level, lymph node metastases, distant metastases, TNM stage, and histology were effective predictors of survival, whereas 18q21 LOH did not show predictive power. The simultaneous deletion of a variety of cancer‐related genes with different and even opposite roles might explain why, apparently, 18q21 LOH does not per se contribute significantly to the natural history of gastric cancer, despite strong correlation with stage. Copyright

Validation of the SPF10 LiPA human papillomavirus typing assay using formalin-fixed paraffin-embedded cervical biopsy samples

ABSTRACT Lower levels of performance of human papillomavirus (HPV) typing assays in studies using formalin-fixed paraffin-embedded (FFPE) tissue compared to those using exfoliated cervical cells have been reported. The interpretation of current studies is limited by bias in inclusion criteria, sample matching, and methods of cell collection. We aimed to validate FFPE tissue for typing by the use of the SPF10 LiPA assay, comparing cervical scrapings to punch and cone biopsy specimens. We examined 165 paired cervical scraping and FFPE punch biopsy samples, and 66 paired FFPE punch and cone biopsy samples. HPV typing was performed using the SPF10 LiPA assay. Kappa statistics were used to measure interrater agreement. The overall agreement with respect to HPV status was 100%. For 74.5% of subjects (kappa = 0.6147), the same numbers of HPV types were detected in scraping and biopsy specimens. The overall positive typing agreement was 95.4% (range, 93.4 to 97.3) for 441 out of 484 individual HPV type analyses. Agreement was good for HPV-39, -42, -43, and -70 (kappa = 0.6506 to 0.7166), excellent for HPV-6, -16, -18, -31, -33, -35, -40, -51, -52, -56, -58, and -66 (kappa = 0.8499 to 0.9665), and absolute for HPV-11, -44, -45, -53, and -68. In 43.9% of cases (kappa = 0.247), the same numbers of HPV types were found in punch and cone biopsy specimens. Overall positive agreement for typing was 86.8% (range, 82.5 to 91.1) for 204 out of 266 individual HPV type analyses. More infections by HPV-18, -33, -51, and -52 were detected in cone specimens. HPV typing by SPF10 LiPA performed equally well for cervical scraping specimens and standard pathological material. Some viral types are preferentially detected in cone specimens, likely reflecting better sampling of diseased epithelium and endocervix tissue.

Oral HPV infection and persistence in patients with head and neck cancer

OBJECTIVE To investigate the presence and persistence of human papillomavirus (HPV) infection in the oral mucosa of patients with head and neck squamous cell carcinoma (HNSCC), and its correlation with prognosis. STUDY DESIGN HPV infection was characterized in tumors and pre and posttreatment oral scrapings in 51 patients with HNSCC and matched controls using the SPF10 LiPA Extra assay. p16INK4A immunostain and in situ hybridization for high-risk HPV genotypes recognized transcriptionally active infection in tumor samples. The risk of infection was compared in patients and controls. The association of pretreatment HPV status with recurrence and survival and with posttreatment HPV persistence was assessed. RESULTS Oral HPV infection risk was significantly higher in patients with HNSCC than in controls (P < .001). Oral HPV infection was associated with infection in the first posttreatment scrapings (P = .015), but did not affect recurrence or prognosis. CONCLUSION Oral HPV infection is frequent in patients with HNSCC and has no prognostic implications, suggesting that posttreatment polymerase chain reaction monitoring on oral cells is not effective to monitor patient recurrence risk.

Identification of transcriptionally active HPV infection in formalin-fixed, paraffin-embedded biopsies of oropharyngeal carcinoma

Human papillomavirus (HPV) oncogenic activity is the result of viral oncogene E6 and E7 expression in infected cells. Oncogene expression analysis is, however, not part of the routine diagnostic evaluation of HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) since it requires fresh tumor tissue. We compared the diagnostic accuracy of several methods commonly employed for HPV characterization in OPSCC with the results of the newly available HPV E6/E7 mRNA in situ hybridization (ISH) on formalin-fixed, paraffin-embedded biopsy samples, in order to establish if the latter should be introduced in the diagnostic routine to increase accuracy when fresh tissue is not available. p16 immunostain, DNA ISH for high-risk HPV genotypes, SPF LiPA amplification and genotyping, and HPV16 E6 amplification were performed on 41 consecutive OPSCC samples. Twenty (48.7%) cases were positive by mRNA ISH; sensitivity and specificity were 100% and 90% for p16, 90% and 100% for DNA ISH, 70% and 76% for SPF10 LiPA, 90% and 76% for E6 amplification. A diagnostic algorithm considering p16 immunostain as first step followed by either high-risk HPV DNA ISH or HPV16 E6 amplification in p16-positive cases correctly characterized 90% of mRNA-positive and all mRNA-negative cases; combining the 3 tests correctly identified all cases. While no stand-alone test was sufficiently accurate for classifying HPV-associated OPSCC, the high sensitivity and specificity of the established combination of p16 immunostain, DNA ISH, and HPV16 DNA amplification suggests that the introduction of labour- and cost-intensive mRNA ISH, is not necessary in the diagnostic routine of oropharyngeal tumors.

Markers of squamocolumnar junction cells in normal tonsils and oropharyngeal cancer with and without HPV infection

HPV infection has been identified recently as the causative agent of a subset of squamous cell carcinomas arising in oropharyngeal tonsils. Factors influencing the susceptibility of tonsillar epithelium to HPV-induced oncogenesis are far from being elucidated. A 5-protein signature including cytokeratin (CK)7, anterior gradient (AGR)2, cluster differentiation (CD)63, matrix metalloproteinase (MMP)7, and guanine deaminase (GDA) has recently been found to identify a residual embryonic cell population in the squamocolumnar (SC) junction of the cervix, susceptible to HPV infection, and cancers originating from these cells. The expression of SC junction markers was investigated with immunohistochemistry in normal tonsils and in oropharyngeal carcinomas (OPC) fully characterised for HPV. All markers were constantly expressed in the reticulated epithelial cells of the tonsillar crypts, with variable diffusion and intensity; in OPC, positivity was observed in 36,5%, 29,2%, 39%, 17%, and 25% of cases with respectively AGR2, CK7, GDA, CD63, and MMP7 antibodies. No OPC was positive for all markers; 6 were completely negative. AGR2 and CK7 showed significant association with tumor- and HPV-related parameters. AGR2 expression was associated with tumor origin in the tongue base (p=0.013); CK7 was associated with non-keratinising morphology (p=0.013). p16 tumor cell expression was associated with AGR2 (p=0.021); transcriptionally active HPV infection was associated with AGR2 and CK7 (p=0.024 and 0.043). Expression of SC junction markers in tonsillar crypt cells might be related to the embryological development of tonsillar structures; their partial association with HPV oncogenic infection could help to identify HPV-susceptible cells and related OPC.

Time trends of human papillomavirus type distribution in Italian women with cervical intraepithelial neoplasia (CIN)

OBJECTIVE It is assumed that the circulation of HPV types in a population is stable over time although there are limited historical data to support this view. The existence of possible cohort effects in the circulation of HPV types has major implications for vaccination strategies and risk assessment in HPV-infected women. We analysed archival biopsy samples of cervical intraepithelial neoplasia (CIN) to study the distribution of HPV types in Northern Italy over the years 1985-2007. METHODS DNA from formalin-fixed paraffin-embedded cervical biopsies from the years 1985-87 (67 samples) and 1995-97 (92 samples) was HPV-typed by the SPF-(10) Lipa assay. Cases were compared with 159 control biopsies from the years 2005-07 matched by patient age and CIN grade. Quantitative PCR was used to compare titres of HPV sequences in DNA extracted from biopsies of the three periods. Type-specific PCR was used to confirm HPV51 and 52 typing by SPF-(10) Lipa. RESULTS HPV51, 52, 53, 56, 58, and 66 were markedly under-represented or undetectable in samples from past periods whereas they represented 5.7-30.8% of present infections. Frequency of multiple HPV infections and high-risk infections (p=0.0001) also increased in recent years. The main changes occurred over the last decade. Infections by HPV16, 18, were three times more frequent 20 years ago than today (p=0.012). Loss of amplifiable HPV sequences over prolonged storage was not observed. Type-specific PCR confirmed all HPV51 and 52 infections. CONCLUSIONS Secular trends in the distribution of HPV types among women with CIN may occur in specific populations.

Exfoliated cells of the oral mucosa for HPV typing by SPF10 in head and neck cancer.

HPV infection in the superficial cells of the oral mucosa could reflect the presence of HPV in head and neck cancer cells. Due mostly to the use of heterogeneous analytical methods, discordant data exist in the literature regarding the agreement between the presence of HPV in non-neoplastic oral mucosa and in tumour tissue from the same patient. The presence of HPV DNA and viral types were compared in paired cytological and biopsy samples from 56 patients with head and neck neoplastic and preneoplastic lesions using the highly sensitive SPF10 LiPA Extra assay, which has been validated recently for formalin-fixed paraffin-embedded tissue using paired cervical cytology and biopsy samples. Kappa statistics were used to measure the inter-rater agreement. The overall agreement with respect to HPV infection was 96.43% (kappa=0.8367). For 76.79% of subjects (kappa=0.6937), the same number of HPV types was detected in cytological and biopsy specimens. The overall positive typing agreement was 90.90%, comprising 130 out of 143 individual HPV type analyses. The agreement shown was good for HPV 18, 44, 45, 54 and 66 (kappa=0.6585-0. 7321), excellent for HPV 6, 16, 40, and 54 (kappa=0.8108-0.8679), and absolute for HPV 11, 31, 33, 35, 39, 51, 52, 53, 59, 74, and 69-71 (kappa=1.0000). The high sensitivity of the SPF10 LiPA and its excellent performance both for recognising HPV infection and for identifying the viral types present in tumour tissue and in oral exfoliated cells make it a useful method for the assessment of HPV infection in patients with head and neck cancer. The excellent agreement for HPV infection and genotyping in paired samples suggests that oral exfoliated cells can be used for HPV detection in the head and neck region.