Infection and disease: cause and cure

Much can be learnt about the mechanisms by which micro‐organisms cause disease from the ways that they interact with cells and tissues. This issue of The Journal of Pathology contains articles that address the roles that cell and tissue biology and pathology are playing in the elucidation of these mechanisms. A review of variant Creutzfeldt–Jakob disease is followed by a discussion of severe acute respiratory syndrome (SARS). Two articles on human papillomavirus (HPV) infection address the association between viral infection and neoplasia, as do reviews on viruses and lymphoma/leukaemia, and Kaposi's sarcoma‐associated herpesvirus (human herpesvirus 8, HHV8). The section on viral disease concludes with an article on morbilliviruses. The intracellular effects of bacteria are addressed in a review of Listeria infection and a further review outlines recent advances in our knowledge of syphilis. Reviews on Helicobacter and gastric neoplasia, innate defences against methicillin‐resistant Staphylococcus aureus (MRSA) infection, and the function of granulomas in tuberculosis also address aspects of tissue responses to bacterial infection. Following a review of the function of immunoglobulin A in defence against infection, a group of articles considers vaccination and gene therapy approaches, the latter involving consideration of both viral and bacterial strategies. The reviews assembled here bridge several gaps: between microbiology and cellular pathology; between host and infecting organism; and between disease and therapy. It is clear that cell and tissue pathology approaches are of value in all of these spheres, providing cell and tissue relevance to microbiological and immunological observations. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Genomic integration of oncogenic HPV and gain of the human telomerase geneTERC at 3q26 are strongly associated events in the progression of uterine cervical dysplasia to invasive cancer

Recently proposed events associated with the progression of cervical intraepithelial neoplasia (CIN) 2/3 to cervical carcinoma include integration of human papillomavirus (HPV) into the host genome, genomic instability, and an increase in chromosome 3q copy number. In particular, the gene coding for the RNA component of telomerase (TERC) at 3q26 has been implicated as a possible candidate gene. Since it is not known to date how these events are temporally related during cervical carcinogenesis, the aim of the present study was to assess the correlation between TERC gene copy number and the physical status of HPV during progression in cervical neoplasia. Solitary precursor lesions of the uterine cervix (CIN 2/3, n = 17), lesions associated with a micro-invasive carcinoma (CIN 3&mCA, n = 13), and advanced invasive carcinomas (invCA, n = 7) were analysed by fluorescence in situ hybridization (FISH) to determine the physical status of the virus and TERC gene copy number. The TERC gene was increasingly gained with progression of CIN 2/3 (3 of 17) through CIN 3&mCA (7 of 13) to invCA (5 of 7). In the lesions exhibiting gain of TERC, the virus was predominantly integrated. This was seen in eight of ten diploid lesions, indicating that these events can occur prior to aneuploidization and are strongly associated with the progression of CIN 3 to mCA and invCA (p < 0.001). With progression to carcinoma, a number of these lesions show polyploidization, resulting in aneuploidy and high TERC gene copy numbers. In conclusion, genomic integration of oncogenic HPV and gain of the human telomerase gene TERC appear to be important associated genetic events in the progression of uterine cervical dysplasia to invasive cancer.

Villoglandular adenocarcinoma of the cervix: Clarity is needed on the histological definition for this difficult diagnosis

BACKGROUND

Villoglandular adenocarcinoma (VGA) of the cervix is reported as a variant of a cervical adenocarcinoma with a good prognosis.

CASES

We present two cases histologically reported as a villoglandular adenocarcinoma of the cervix that have recurred and progressed rapidly since initial treatment. External histopathological review suggested both had a prominent villoglandular pattern but with an associated underlying well-differentiated adenocarcinoma.

CONCLUSION

The diagnosis of VGA is difficult. Current literature is not entirely consistent in the presented definition, and further clarity is needed. Because of the rarity of VGA and the difficulty but importance of the diagnosis, we would feel that a central review of all cases of VGA is warranted. This would assist in diagnosis and also in obtaining accurate follow-up data.

The pathology and management of endocervical glandular neoplasia

The incidence of cervical glandular intraepithelial neoplasia and adenocarcinoma is rising, and our limited knowledge about these lesions presents the gynecologist with a management dilemma. Recently, pathologists have paid increasing attention to the diagnosis and pathogenesis of adenocarcinoma of the cervix. Although there is no uniformity in the management of these lesions, nonradical surgery appears to give satisfactory results especially in young women who want to preserve their fertility. This review focuses on the issues surrounding the histologic diagnosis of endocervical glandular abnormalities, including their classification, and discusses the management of cervical preinvasive glandular disease, including follow-up after treatment.

Upregulation of heat shock protein 27 in metaplastic and neoplastic lesions of the endocervix

Heat shock proteins (hsps) are molecular chaperones that are known to play a pivotal role in regulating intracellular homeostasis. hsp27 may have diagnostic and prognostic values for different gynecological malignancies. A cross-sectional analytical study was conducted at the Department of Pathology, The University of Liverpool, Liverpool, UK. Included in the study were 80 cervical glandular lesions of various histologic types, representing tuboendometrial metaplasia/endometriosis (n = 19), cervical glandular intraepithelial neoplasia (n = 33), and invasive adenocarcinoma (n = 28). Paraffin-embedded sections were stained using a commercial mouse monoclonal anti-hsp27 antibody with prior pressure-cooking for antigen retrieval. Sections of 11 normal cervices were used as controls. The median percentage of cells expressing hsp27 in each group was calculated. Normal cervical glands showed minimal expression of hsp27 (median: 10%, interquartile ranges [IQ]: 5-15). Expression was significantly more widespread in tuboendometrial metaplasia/endometriosis (median: 35%, IQ: 15-80), cervical glandular intraepithelial neoplasia (median: 60%, IQ: 32-80), and invasive adenocarcinoma (median: 40%, IQ: 25-80) when compared with normal endocervix (P = 0.007, < 0.001, and 0.001, respectively). However, no significant difference in hsp27 protein expression was found between cervical glandular intraepithelial neoplasia and invasive adenocarcinoma. In invasive adenocarcinoma, hsp27 showed no correlation with tumor grade, lymph node involvement, and lymphovascular space invasion. Our data highlight early dysregulation of hsp27 expression in both metaplastic and neoplastic lesions of the cervix.

Medium-term results of extracorporeal membrane oxygenation for severe acute lung injury after lung transplantation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been used successfully for early, severe reperfusion injury after lung transplantation. The purposes of this study are to: (1) document the medium-term survival of patients treated with ECMO; and (2) assess the extent of recovery of their pulmonary function.

METHODS

We retrospectively reviewed charts of 172 patients having lung transplants at our institution from 1997 through 2002. The group included 16 patients (9% of total; 10 bilateral, 5 single, 1 living lobar) treated with ECMO for primary allograft failure after single or bilateral single-lung transplantation. Survival and bronchiolitis obliterans syndrome (BOS)-free survival rates were calculated. Pulmonary function was assessed at 2 months, 1 year and 2 years post-transplant.

RESULTS

Median hospital stay was 48 days for the ECMO group and 16 days for the overall group (p < 0.05). The 90-day survival was 60% in the ECMO group, and 90% in the overall group. The 2-year survival was 46% in the ECMO group, and 69% in the overall group. Mean forced expiratory volume in 1 second (FEV(1)) in the ECMO group at 1 year was 59 +/- 13% of predicted, and at 2 years 60 +/- 15% of predicted; it was not significantly different for the overall group.

CONCLUSIONS

Patients treated with ECMO for primary allograft failure after lung transplantation showed acceptable medium-term survival and pulmonary function.

A retrospective clinical audit of cervical smears reported as 'glandular neoplasia'

The aims of this study were to review the diagnostic pathway of women with smears reported as 'glandular neoplasia' and to outline the management, colposcopy findings, treatment and final histological diagnosis in these women. The design was a retrospective review. A total of 114 women were identified over a 5-year period from the cytology database at the Royal Liverpool University Hospital Cytology Department, whose hospital case notes were available for review. Methods included a review of the case notes for the demographic details, indication for smear, colposcopic findings, investigation and/or treatment procedures, histology, final diagnosis and current disease status. Of 114 smears reported as 'glandular neoplasia', 67 were reported as consistent with cervical glandular intra-epithelial neoplasia (CGIN), six with endocervical adenocarcinoma, 36 with endometrial adenocarcinoma and five with other glandular neoplastic abnormalities. The average age was 46.5 years. 79 (69.3%) smears were routine call/recall and 36 (30.7%) women were symptomatic. The positive predictive value (PPV) for a significant histological abnormality in the CGIN smear group was 80.6% (23.9% invasive carcinomas, 43.3% CGIN and 13.4% CIN) and the PPV of an 'endometrial adenocarcinoma' smear was 86.1%. Smears indicating glandular neoplasia are associated with a high probability of clinically significant lesions, the PPV of a CGIN smear being over 80%. Immediate referral for colposcopy and assessment by an experienced colposcopist is recommended.

Application of laser capture microdissection combined with two-dimensional electrophoresis for the discovery of differentially regulated proteins in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal of all the common malignancies and markers for early detection or targets for treatment of this disease are urgently required. The disease is characterised by a strong stromal response, with cancer cells usually representing a relatively small proportion of the cells in the tumor mass. We therefore performed laser capture microdissection (LCM) to enrich for both normal and malignant pancreatic ductal epithelial cells. Proteins extracted from these cells were then separated by two-dimensional gel electrophoresis (2-DE). The limited amounts of protein in the LCM procured samples necessitated the detection of 2-DE resolved proteins by silver staining. Consequently, loading equivalent amounts of protein onto gels was essential. However, we found that conventional means of measuring total protein in the samples were not sufficiently accurate. We therefore adopted a strategy in which the samples were first separated by one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis, stained with silver stain and subjected to densitometry. Evaluation of the staining intensity was then used to normalise the samples. We found that the protein profiles from undissected normal pancreas and LCM-acquired non-malignant ductal epithelial cells from the same tissue block were different, underpinning the value of LCM in our analysis. The comparisons of protein profiles from nonmalignant and malignant ductal epithelial cells revealed nine protein spots that were consistently differentially regulated. Five of these proteins showed increased expression in tumor cells while four showed diminished expression in these cells. One of the proteins displaying enhanced expression in tumor cells was identified as the calcium-binding protein, S100A6. To determine the incidence of S100A6 overexpression in pancreatic cancer, we carried out immunohistochemical analysis on sections from a pancreas cancer tissue array containing 174 duplicate normal and malignant pancreatic tissue samples, from 46 pancreas cancer patients. Normal pancreatic ductal epithelia were either devoid of detectable S100A6 or showed weak expression only. Moderately or poorly differentiated tumors, by contrast, showed a higher incidence and a higher level of S100A6 expression. These observations indicate that the combination of LCM with 2-DE provides an effective strategy to discover proteins that are differentially expressed in PDAC.

Induction of tetrasomy by human papillomavirus type 16 E7 protein is independent of pRb binding and disruption of differentiation

We have demonstrated previously that high-risk human papillomaviruses (HPVs) induce tetrasomy in low-grade squamous intraepithelial lesions of the cervix. In this study we show that the E6 and E7 genes of high-risk HPV-16, but not those of low-risk HPV-6, are independently able to induce tetrasomy when constitutively expressed in proliferating monolayer cultures of primary human keratinocytes. Of seven HPV-16 E7 mutants analysed (H2P, Delta6-10, Delta21-24, C24G, S31G/S32G, A50S and S71I), five were severely impaired in their ability to induce tetrasomy in monolayer and raft culture. Only mutant C24G induced tetrasomy to levels comparable with wild-type E7 in monolayer and raft culture. This mutant shows strongly reduced binding to the retinoblastoma gene product pRb. The casein kinase II phosphorylation defective mutant S31G/S32G induced tetrasomy to levels comparable with wild-type E7 in raft culture, but not in monolayer culture, and induction of tetrasomy did not correlate with raft morphology. These results indicate that pRb protein binding is not required for HPV-16 E7 associated tetrasomy and that tetrasomy is not directly related to the ability of this protein to disrupt keratinocyte differentiation.

Overexpression of cyclins A and B as markers of neoplastic glandular lesions of the cervix

INTRODUCTION

Cyclins are a family of regulatory proteins that play a pivotal role in controlling the cell cycle. While there is evidence of their altered expression in cervical squamous lesions, their precise role in glandular neoplasia is yet to be elucidated.

OBJECTIVES

To investigate the role of cyclins as markers of early cervical glandular neoplasia by comparing their expression in lesions of different histological type.

METHODS

Through a cross-sectional analytical study, paraffin wax sections of normal cervix (n = 11), endometriosis/tubo-endometrioid metaplasia (TEM) (n = 19), cervical glandular intraepithelial neoplasia (CGIN) (n = 33), and invasive adenocarcinoma (n = 28) were studied using monoclonal antibodies for cyclins A, B, D, and E with heat pretreatment for antigen unmasking. A quantitative assessment was employed for the analysis of percentage expression of each marker. Statistical analysis of data was performed using SPSS.

RESULTS

A progressive significant increase in cyclin A expression occurred from normal cervix (median: 0, IQ: 0-0), through endometriosis/TEM (median: 1, IQ: 0-15) and CGIN (median: 15, IQ: 0-30) to invasive adenocarcinoma (median: 40, IQ: 21.25-60). Cyclin B exhibited a similar pattern (median: 0, IQ: 0-0, median: 0, IQ: 0-0.5, median: 8, IQ: 0.75-15, and median: 30, IQ: 15-45, respectively). Statistically higher expression of cyclin B was found in CGIN than in TEM/endometriosis (P < 0.001). Invasive adenocarcinomas expressed higher levels of cyclins A and B than CGIN (P < 0.001). There was significantly greater cyclin E expression in TEM/endometriosis than in normal cervix (P = 0.03) with a nonsignificant further increase in CGIN and invasive adenocarcinoma. The expression of cyclin D was not significantly different among all groups.

CONCLUSIONS

Our data indicate that up-regulation of cyclin A and B expression occurs in neoplastic lesions of the cervix. Cyclin B expression was significantly more widespread in CGIN lesions than in TEM/endometriosis indicating that further assessment of the value of this marker in the diagnosis of cervical glandular neoplasia is warranted.

Use of the nested reverse transcription-polymerase chain reaction for the detection of human papillomavirus 16 E6 transcriptional activity in cervical cancer: a technical perspective

AIM

The aim of this study was to evaluate HPV 16 E6 expression using nested RT-PCR in cervical tumour tissue and compare this technique with standard RT-PCR in a group of patients using injectable contraceptive steroids.

PATIENTS AND METHODS

Tumour DNA was analysed for the presence and type of HPV by polymerase chain reaction (PCR) from 120 cervical cancer samples. Ribonucleic acid (RNA) was extracted from cervical tissue samples and cell-lines. Reverse transcription was carried out on all samples using reverse transcriptase enzyme to form single-stranded cDNA. The GAPDH (glyceraldehyde-3-phosphate dehydrogenase) housekeeping gene was used.

RESULTS

The majority of patients had squamous cell carcinoma. Of 120 cervical tissue samples, there were 111 samples with confirmed HPV 16 infection. RNA was extracted in only 86 samples. Of these, 23 samples contained genomic DNA. Of the remaining 63 patients, there were 53 patients who had expression of HPV-type 16. E6 full-length gene expression. In total there were 25 patients (40%) with expression of the HPV 16 E6*I gene and 30 patients with expression of the E6*II gene. The nested PCR method using S1/S2 primers detected 54 patients with the E6*I & E6*II transcripts in comparison to classical PCR which detected only 31 such transcripts.

CONCLUSION

Nested RT-PCR is the method of choice to determine the role of different E6/E7 splice products in HPV-associated carcinogenesis.

The interaction between steroid hormones, human papillomavirus type 16, E6 oncogene expression, and cervical cancer

Various risk factors have been implicated in the causation of cervical cancer including human papillomavirus (HPV), the early genes (E6 and E7 ) of which encode the main transforming proteins. Studies have suggested that steroid hormones may enhance the expression of these genes leading to loss of p53 gene-mediated cell apoptosis. A total of 120 cervical tissue samples were obtained from patients with proven cervical cancer. Patients who used depo-medroxyprogesterone acetate steroid contraception were recruited as part of the steroid arm. Only HPV DNA type 16 samples were used for the study. Controls included three cell lines (CaSki, SiHa, & C33A) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as an internal housekeeping gene. Of 120 patients, there were 111 patients with HPV type 16 identified. Of this number, RNA was present in 63 samples. There were 30 women (30/63) who used steroid contraception. In relation to patients who used contraception, HPV 16 E6 gene expression was present in 79% (n = 23) and 88% (n = 30) of steroid users compared to nonusers, respectively. In total there were 25 patients (40%) with expression of the HPV 16 E6*I gene and 30 patients with expression of the E6*II gene. There were 57% of steroid users (n = 17) who had expression of the E6*I/E6*II gene, compared to 52% (n = 17) of nonusers (P = 0.800). From a molecular level, this study does not confirm the role of injectable progesterones in cervical carcinogenesis.

CD10 and calretinin staining of endocervical glandular lesions, endocervical stroma and endometrioid adenocarcinomas of the uterine corpus: CD10 positivity is characteristic of, but not specific for, mesonephric lesions and is not specific for endometrial stroma

AIMS

In the female genital tract CD10 has been used to assist in the evaluation of mesenchymal tumours of the uterus and in determining whether endometrial stroma is present. CD10 positivity has also been shown in cervical mesonephric remnants and this antibody has been suggested as a useful immunohistochemical marker of mesonephric lesions in the female genital tract. Calretinin has also been shown to be positive in mesonephric lesions. In this study the specificity of these two antibodies in evaluating cervical and uterine glandular lesions and the value of CD10 in determining whether stroma is endometriotic or not were investigated.

METHODS AND RESULTS

Cases of cervical tubo-endometrial metaplasia (TEM) (n = 11), microglandular hyperplasia (MGH) (n = 10), endometriosis (n = 8), mesonephric remnants/hyperplasia (n = 12), endocervical adenocarcinoma, usual type (n = 15), mucinous variant of minimal deviation adenocarcinoma (MDA) (n = 7) and mesonephric adenocarcinoma (n = 3) were stained with antibodies against CD10 and calretinin. Nine cases of endometrial adenocarcinoma of endometrioid type were also stained. In all the cervical cases normal endocervical glands were negative with both antibodies except for one case with strong positive luminal staining with CD10. All cases of TEM, MGH and endometriosis were negative with CD10 and calretinin except for focal staining with CD10 in one case each of MGH (cytoplasmic staining) and endometriosis (luminal staining). Most usual endocervical adenocarcinomas were negative with both antibodies, although one exhibited focal cytoplasmic staining with calretinin and five exhibited limited luminal positivity with CD10. All MDAs were negative with both antibodies. Ten of 12 mesonephric remnants/hyperplasia showed luminal positivity with CD10 and one exhibited cytoplasmic and nuclear staining with calretinin. Two of three mesonephric adenocarcinomas showed luminal positivity with CD10 and nuclear and cytoplasmic positivity with calretinin. Seven of nine endometrial adenocarcinomas were positive with CD10 (four cytoplasmic, two membranous and cytoplasmic, one luminal and cytoplasmic) and three with calretinin (two cytoplasmic, one nuclear and cytoplasmic). Positive staining of endometriotic stroma with CD10 was present in all endometriosis cases but normal cervical stroma was also strongly positive, especially around glands. Endometriotic stroma and cervical stroma were negative with calretinin.

CONCLUSIONS

We conclude that most endocervical glandular lesions, including mesonephric remnants/ hyperplasia, are negative with calretinin. However, the focal nuclear and cytoplasmic positivity with calretinin in two of three mesonephric adenocarcinomas suggests that this may be a useful indicator of a mesonephric origin of a cervical adenocarcinoma. Most mesonephric remnants/hyperplasias exhibit luminal positivity with CD10, although this is not invariable and staining is usually focal. Positive luminal staining of a benign endocervical glandular lesion with CD10 may help confirm mesonephric remnants. Although positive staining with CD10 was found in two of three mesonephric adenocarcinomas, the observed immunoreactivity of several conventional cervical adenocarcinomas limits the diagnostic value of CD10 in confirming a mesonephric origin for an adenocarcinoma. Since all cervical MDAs were negative with CD10, positivity with this antibody may be of value in distinguishing mesonephric hyperplasia from MDA, although this distinction rarely necessitates immunohistochemistry. Most endometrial adenocarcinomas of endometrioid type stain with CD10 and thus positivity with this antibody is not specific for a mesonephric origin of an endometrial adenocarcinoma. Positivity of normal cervical stroma limits the value of CD10 staining in confirming a diagnosis of cervical endometriosis.

The role of steroid contraceptive hormones in the pathogenesis of invasive cervical cancer: a review

Invasive cervical cancer remains a leading cause of morbidity and mortality, especially among women in the developing world where screening is either deficient or absent. Of all agents linked to the causation of this disease, high-risk human papillomavirus (HPV) appears to be the strongest factor. However, not all women with HPV develop cervical cancer. Steroid contraception has been postulated to be one mechanism whereby HPV exerts its tumorigenic effect on cervical tissue. Steroids are thought to bind to specific DNA sequences within transcriptional regulatory regions on the HPV DNA to either increase or suppress transcription of various genes. Although some earlier studies were reassuring as no increased incidence of cervical cancer was observed, subsequent research has shown a causative association, especially among long-term users. The role of steroids was further enhanced by the discovery of hormone receptors in cervical tissue. Some earlier studies of oral contraceptive steroids found no increased risk, even after controlling for other risk factors, including smoking and number of partners. However, prospective studies have shown a greater progression of dysplasia to carcinoma-in-situ with more than 6 years of oral steroid contraceptive use. Similar findings were also evident from other work, including the Royal College of General Practitioners Oral Contraception Study. The WHO Collaborative Study of Neoplasia and Steroid Contraceptives showed a relative risk of 1.2 for invasive cancer in users of the long-acting progestational contraceptive, depo-medroxyprogesterone acetate. However, in users of more than 5 years duration, an estimate of 2.4 was reported. The upstream regulatory region (URR) of the HPV type 16 viral genome, mediates transcriptional control of the HPV genome and is thought to contain enhancer elements that are activated by steroid hormones. It has been shown that steroid hormones bind to specific glucorticoid-response elements within HPV-DNA. Experimental evidence has revealed that high-risk type HPV 16 are able to stimulate the development of vaginal and cervical squamous cell carcinomas in transgenic mice exposed to slow-release pellets of 17 beta-estradiol in the presence of human keratin-14 promoter. Squamous cell carcinomas developed in a multi-stage pathway only in transgenic mice and not in nontransgenic mice. The E6 oncoprotein of HPV 16 has been shown to bind to the p53 tumor suppressor gene and stimulate its degradation by a ubiquitin-dependent protease system. Steroid hormones are thought to increase the expression of the E6 and E7 HPV 16 oncogenes, which in turn bind to and degrade the p53 gene product, leading to apoptotic failure and carcinogenesis. However, the molecular basis of this remains to be proven.

Expression ofPAX 3 alternatively spliced transcripts and identification of two new isoforms in human tumors of neural crest origin

The developmental gene PAX 3 is expressed in the early embryo in developing muscle and elements of the nervous system, including the brain. Since no one has investigated the expression of the isoforms of PAX 3 in the neuroectodermal tumors melanoma and small cell lung cancer (SCLC), we have carried out a comprehensive screening for the expression of the isoforms PAX 3a-e using RT-PCR in human melanoma cell lines, primary human ocular and secondary cutaneous melanomas. We have identified 2 new isoforms of PAX 3, g and h, which we have isolated, cloned and sequenced. Sets of primers for each isoform were designed and their specificity was confirmed by sequence analysis of the products. The isoforms PAX 3a-e were detected in all human cutaneous melanoma cell lines (8/8), but only PAX 3c (1/2) and PAX 3d (2/2) in ocular melanoma cell lines. The same PAX 3 isoforms were detected in more than 80% of human cutaneous melanomas: PAX 3a and b (15/17), PAX 3c (14/17), PAX 3d (16/17) and PAX 3e (15/17). In contrast the results for 7 SCLC cell lines were PAX 3a (0/7), PAX 3b (1/7), PAX 3c (3/7), PAX 3d (6/7), PAX 3e (2/7); 8/8 cutaneous melanoma cell lines and 8/8 ocular melanoma tissues, together with 14/17 cutaneous melanoma tissues screened, expressed the new isoform PAX 3g. All 8 cutaneous melanoma cell lines expressed PAX 3h, but it was not detectable in any of the tumor tissues (0/20). Neither of the 2 ocular melanoma cell lines expressed the 2 new isoforms. Comparison of the different amplicon staining intensities on a gel suggests that PAX 3c and PAX 3d are the predominant transcripts expressed, with relatively low expression of PAX 3e and PAX 3h. We propose that these and the 2 new isoforms we have discovered may be important in oncogenesis and differential diagnosis of melanomas or SCLC.

The association of viral infection and chronic allograft nephropathy with graft dysfunction after renal transplantation

BACKGROUND

The long-term effect of viral infections on graft dysfunction and rejection after renal transplantation is uncertain.

METHODS

A cohort of 37 renal transplant recipients was followed prospectively for 3 years. Creatinine clearance rate at 6 months and 3 years and chronic allograft nephropathy were correlated with the detection of cytomegalovirus (CMV), human herpesvirus 6 and human herpesvirus 7 and BK virus DNA, CMV disease, and acute rejection.

RESULTS

CMV disease was significantly associated with poor graft function at 6 months, whereas chronic allograft nephropathy was associated with graft dysfunction at 3 years. Both CMV disease and detection of human herpesvirus 6 DNA were associated with chronic allograft nephropathy.

CONCLUSIONS

CMV disease was a significant cause of early graft dysfunction, whereas the presence of chronic allograft nephropathy was the main determinant of poor long-term graft function. The role of viral infections in chronic allograft nephropathy deserves further investigation.

Loss of cytokeratin 14 expression is related to human papillomavirus type and lesion grade in squamous intraepithelial lesions of the cervix

In a recent study of low-grade cervical squamous intraepithelial lesions (SILs), we reported that infection with both low- and high-risk human papillomaviruses (HPVs) upregulated cyclin A, B, E, and Ki67 expression in basal and suprabasal cells. In view of the intricate link between cell cycle exit, proliferation, and differentiation, we examined the morphologic distribution of cytokeratins 13 and 14 and involucrin expression in 49 low-grade SILs infected with HPV types 6, 11, 16, 18, 31, 33, 39, 42, 43, 44, 45, 51, 52, 56, 58, and 66; 2 lesions contained both low- and high-risk HPVs. The findings were compared with 30 high-grade SILs infected with HPV types 16, 31, 33, 51, 58, 66, and 67; 3 of these were infected with 2 different HPVs. In low-grade lesions, the differentiation markers were expressed normally, showing that differentiation proceeds despite upregulation of cell cycle--associated proteins. Loss of involucrin (3 of 33) and cytokeratin 13 (8 of 33) expression occurred only in the high-grade lesions and was therefore related to lesion grade. Loss of cytokeratin 14 expression was also significantly more frequent in high-grade than in low-grade lesions (19 of 33 v 12 of 51; P < .01). In addition, cytokeratin 14 expression was significantly less frequent in the intermediate and superficial layers of low-grade SILs infected with high-risk HPVs than in those infected with low-risk HPVs (3 of 27 v 14 of 24; P < .001). These findings are consistent with in vitro data and suggest that abnormalities of both cell cycle control and squamous differentiation are important in HPV-associated neoplastic transformation.

Allelic imbalance is not restricted to numerically abnormal chromosomes in epithelial ovarian tumours

In this study, 23 low malignant potential (LMP) and 27 invasive epithelial ovarian tumours have been examined by microdissection and microsatellite polymerase chain reaction (PCR) for allelic imbalance (AI) at loci on the p and q arms of chromosomes 1, 11, 17, and X, and the data have been compared with interphase cytogenetics for numerical abnormalities (aneusomy) of these chromosomes. AI was uncommon in LMP tumours (5 of 23 at 9 of 146 informative loci) but was significantly more common (p<0.001) in invasive carcinomas (21 of 27 at 47 of 168 informative loci). This difference remained when LMP tumours were compared specifically with stage I carcinomas (p<0.001). A greater number of loci were involved in AI amongst serous than amongst mucinous carcinomas (p=0.015). AI was present at significantly more loci in carcinomas showing aneusomy by interphase cytogenetics than in those showing no numerical chromosome abnormalities (p<0.001). However, amongst the carcinomas showing aneusomy, AI was as frequent at loci on chromosomes with no numerical abnormality as at those with the numerical changes. These data demonstrate that aneusomy and AI are interrelated phenomena but that AI does not occur simply as a consequence of numerical chromosome changes.

What we could do now: molecular pathology of gynaecological cancer

Gynaecological tumours exemplify many of the molecular paradigms of carcinogenesis. The clinical value of many of the molecular abnormalities present is now being tested and it is likely that the identification of at least some of these will become routine in the near future. This may help to refine diagnosis and guide treatment-for example, therapeutic vaccination for human papillomavirus related disease.

Loss of sequences on the short arm of chromosome 17 is a late event in squamous carcinoma of the cervix

AIMS

To determine by fluorescence in situ hybridisation (FISH) whether deletion of D17S34, a subtelomeric probe for 17p, occurs in invasive squamous carcinoma of the cervix, and to determine the extent of such loss by analysis of the p53 and HER2/NEU genes.

METHODS

Fourteen invasive squamous cell carcinomas of the cervix were investigated by FISH for D17S34, p53, and HER2/NEU. Dual hybridisation of each probe with the chromosome 17 alpha satellite (D17Z1) probe was performed on paraffin wax embedded sections, and the fluorescence ratios of the paired signals were determined. Broad spectrum human papillomavirus (HPV) typing by ISH and GP5+/6+ polymerase chain reaction was also performed.

RESULTS

Twelve tumours were HPV positive, nine with HPV-16, and one each with types 18, 31, and 39. Loss of D17S34 was identified in four tumours, one of which was HPV negative. In one tumour, D17S34 loss was accompanied by loss of p53 only, suggesting that deletion was limited to the p arm. A second tumour showed simultaneous losses of all probes, indicative of whole chromosome 17 loss during tumour growth. The two remaining specimens showed loss of D17S34 only, diffuse in one, and localised within the tumour in the other. Aberrations of p53 or HER2/NEU were not seen independently of D17S34 loss, and loss did not correlate with HPV presence or type.

CONCLUSIONS

These data show that D17S34 loss is prevalent, marking 28% of the invasive squamous carcinomas in this study. The observed intratumoral heterogeneity indicates that, at least in some cases, this loss occurs after invasion and is therefore a late event in the path of cervical carcinogenesis.

Human papillomavirus in pterygium

AIM

To determine the prevalence and significance of human papillomaviral types in conjunctival pterygia.

METHODS

Polymerase chain reaction technology was used to identify the presence of human papillomavirus (HPV) in 10 formalin fixed paraffin embedded pterygia samples. 10 conjunctival papillomas were used as positive controls. 20 conjunctival samples, 10 with primary acquired melanosis and 10 with malignant melanoma, were used as negative controls. Sample subgroups were of equal sex, race, and age distribution to eliminate bias. All samples were further analysed (for 21 HPV types) using dot-blot hybridisation techniques.

RESULTS

HPV was identified in 90% of the conjunctival papillomas, 50% of the pterygia samples, but no HPV was detected in the negative control group. Two pterygia showed type 6, two type 11, and one type 16. These three HPV types were also detected in papillomas.

CONCLUSION

These results suggest that HPV may be involved in the pathogenesis of pterygia and that broadly the same HPV types are found in pterygia and in papillomas. Persistent conjunctival HPV may possibly play a part in the recurrence of pterygia post excision but further larger studies are required to elucidate this hypothesis.