Nafisa Wilkinson

Proteomic Profiling Identifies Afamin as a Potential Biomarker for Ovarian Cancer

Purpose: To discover and validate serum glycoprotein biomarkers in ovarian cancer using proteomic-based approaches. Experimental Design: Serum samples from a “discovery set” of 20 patients with ovarian cancer or benign ovarian cysts or healthy volunteers were compared by fluorescence two-dimensional differential in-gel electrophoresis and parallel lectin-based two-dimensional profiling. Validation of a candidate biomarker was carried out with Western blotting and immunoassay (n = 424). Results: Twenty-six proteins that changed significantly were identified by mass spectrometric sequencing. One of these, confirmed by Western blotting, was afamin, a vitamin E binding protein, with two isoforms decreasing in patients with ovarian cancer. Validation using cross-sectional samples from 303 individuals (healthy controls and patients with benign, borderline, or malignant ovarian conditions and other cancers) assayed by ELISA showed significantly decreased total afamin concentrations in patients with ovarian cancer compared with healthy controls (P = 0.002) and patients with benign disease (P = 0.046). However, the receiver operating characteristic areas for total afamin for the comparison of ovarian cancer with healthy controls or benign controls were only 0.67 and 0.60, respectively, with comparable figures for CA-125 being 0.92 and 0.88 although corresponding figures for a subgroup of samples analyzed by isoelectric focusing for afamin isoform 2 were 0.85 and 0.79. Analysis of a further 121 samples collected prospectively from 9 patients pretreatment through to relapse indicated complementarity of afamin with CA-125, including two cases in whom CA-125 was noninformative. Conclusions: Afamin shows potential complementarity with CA-125 in longitudinal monitoring of patients with ovarian cancer, justifying prospective larger-scale investigation. Changes in specific isoforms may provide further information.

Assignment of primary site in high-grade serous tubal, ovarian and peritoneal carcinoma: a proposal

The revised FIGO 2013 staging for carcinomas of the ovary, fallopian tube and peritoneum has introduced a single system for tumours originating at these sites. The system requires pathologists to assign a primary site (ovary, tube or peritoneum), but does not provide guidance to aid this assignment. This is particularly problematic in cases of advanced‐stage (stage II or greater) high‐grade serous carcinoma (HGSC), where there is commonly involvement of two or more sites by tumour, and practice among pathologists in determining where a tumour has arisen varies widely. This has significant implications for recording of tumour incidence and mortality, data collection by cancer registries, and entry into clinical trials. We propose guidelines for assigning the primary site of HGSC based on careful macroscopic and histological assessment. The use of these guidelines, in conjunction with the new FIGO staging system, is intended to act as an impetus to promote debate and provide a uniform and consistent approach in assigning primary tumour site which will facilitate comparison of data between centres.

Expression patterns of the human papillomavirus type 16 transcription factor E2 in low- and high-grade cervical intraepithelial neoplasia.

Specific antibodies against the C‐terminus of E2, produced by affinity purification of polyclonal antisera, have been used to identify the cellular populations which express the HPV 16 E2 transcription factor, in a series of formalin‐fixed, paraffin‐embedded cervical tissues. Cases were selected for both the presence of HPV 16 DNA (confirmed by multiple gene‐specific PCR detections) and the presence of multiple grades of cervical intraepithelial neoplasia (CIN). The data indicate that E2 expression is highest in CIN I and in koilocytic lesions. Lower expression was observed in CIN II and little in CIN III lesions. In contrast, there was some restoration of E2 expression in invasive carcinomas, although the intracellular distribution was much more diffuse. The location of E2 expression to the superficial layers of the cervical epithelium, as well as the occurrence of some basal expression in CIN I, suggests that antibodies against HPV 16 E2 could be a useful adjunct to standard histological techniques for the detection of ‘at‐risk’ patients as part of a cervical screening programme.Copyright

ASPM and microcephalin expression in epithelial ovarian cancer correlates with tumour grade and survival

Background:The clinico-pathological and molecular heterogeneity of epithelial ovarian cancer (EOC) complicates its early diagnosis and successful treatment. Highly aneuploid tumours and the presence of ascitic fluids are hallmarks of EOC. Two microcephaly-associated proteins, abnormal spindle-like microcephaly-associated protein (ASPM) and microcephalin, are involved in mitosis and DNA damage repair. Their expression is deregulated at the RNA level in EOC. Here, ASPM and microcephalin protein expression in primary cultures established from the ascites of patients with EOC was determined and correlated with clinical data to assess their suitability as biomarkers.Methods:Five established ovarian cancer cell lines, cells derived from two benign ovarian ascites samples and 40 primary cultures of EOC derived from ovarian ascites samples were analysed by protein slot blotting and/or immunofluorescence to determine ASPM and microcephalin protein levels and their cellular localisation. Results were correlated with clinico-pathological data.Results:A statistically significant correlation was identified for ASPM localisation and tumour grade, with high levels of cytoplasmic ASPM correlating with grade 1 tumours. Conversely, cytoplasmic microcephalin was only identified in high-grade tumours. Furthermore, low levels of nuclear microcephalin correlated with reduced patient survival.Conclusion:Our results suggest that ASPM and microcephalin have the potential to be biomarkers in ovarian cancer.

Women with peritoneal carcinomatosis of unknown origin: Efficacy of image-guided biopsy to determine site-specific diagnosis.

Objectives  To evaluate the use of image‐guided biopsy (IGB) in routine clinical practice to obtain site‐specific diagnoses in women presenting with peritoneal carcinomatosis (PC).

Morphologic and Molecular Characteristics of Mixed Epithelial Ovarian Cancers.

Epithelial ovarian cancer (EOC) consists of 5 major histotypes: high-grade serous carcinoma (HGSC), endometrioid carcinoma (EC), clear cell carcinoma (CCC), mucinous carcinoma (MC), and low-grade serous carcinoma (LGSC). Each can have a broad spectrum of morphologic appearances, and 1 histotype can closely mimic histopathologic features more typical of another. Historically, there has been a relatively high frequency of mixed, defined by 2 or more distinct histotypes present on the basis of routine histopathologic assessment, histotype carcinoma diagnoses (3% to 11%); however, recent immunohistochemical (IHC) studies identifying histotype-specific markers and allowing more refined histotype diagnoses suggest a much lower incidence. We reviewed hematoxylin and eosin–stained slides from 871 cases of EOC and found the frequency of mixed carcinomas to be 1.7% when modern diagnostic criteria are applied. Through international collaboration, we established a cohort totaling 22 mixed EOCs, consisting of 9 EC/CCC, 4 EC/LGSC, 3 HGSC/CCC, 2 CCC/MC, and 4 other combinations. We interrogated the molecular differences between the different components of each case using IHC, gene expression, and hotspot sequencing analyses. IHC data alone suggested that 9 of the 22 cases were not mixed tumors, as they presented a uniform immuno-phenotype throughout, and these cases most probably represent morphologic mimicry and variation within tumors of a single histotype. Synthesis of molecular data further reduces the incidence of mixed carcinomas. On the basis of these results, true mixed carcinomas with both morphologic and molecular support for the presence of >1 histotype within a given tumor represent <1% of EOCs.

The secondary Müllerian system, field effect, BRCA, and tubal fimbria: our evolving understanding of the origin of tubo-ovarian high-grade serous carcinoma and why assignment of primary site matters

Summary It has long been held that most epithelial ovarian carcinomas arise from the ovarian surface epithelium. Theories on origin were based on the assumption that there was a common cell of origin for all ovarian carcinoma histotypes, and that these histotypes were closely related and frequently admixed. It is now recognised that the histotypes are distinct diseases. Recent studies on early, organ-confined, non-uterine high-grade serous carcinoma (HGSC) have led to a change in our understanding of their anatomical site of origin. These studies were initially on patients at high risk of developing HGSC but more recently have been extended to cases without family history or genetic markers of increased risk. These have shown that incidental HGSC, when detected before dissemination, is most commonly identified in the tubal fimbria. As a result, we have had to revisit theories on the cell and site of origin of HGSC. This progress in our understanding has necessitated a change in how we handle cases in clinical practice, as it impacts on primary site assignment, which in turn has implications for staging. In this review we will discuss the evolution of our understanding of the cell of origin of HGSC, the evidence for the tubal fimbria as the anatomical site of origin of most non-uterine HGSC, and the clinical implications of these recent developments.

Menopausal Changes in the Myometrium: An Investigation Using a Gnrh Agonist Model

Thirty-four premenopausal women were randomized to receive 3.75 mg of leuprorelin acetate depot or placebo for 8 weeks before hysterectomy. Postoperatively, the myometrium was examined by two independent pathologists and the pathologic features were graded. Computer analysis was used to assess myometrial cellularity and arterial wall structure (on hematoxylin and eosin-stained sections) and vascularity (on sections immunostained for Factor VIII-related antigen). The cellularity of the gonadotrophin-releasing hormone agonist-treated myometrium was higher than the controls with less stromal edema. Focal myometrial hyalinization was present in a minority of cases, all in the gonadotrophin-releasing hormone agonist-treated cases. The arteries in the gonadotrophin-releasing hormone agonist-treated uteri underwent atrophy of the tunica media and had significantly more perivascular fibrosis. The number of vessels per 100 myocytes also was decreased. Hypoestrinism secondary to leuprorelin treatment leads to myocyte atrophy, decreased stromal edema, atrophy of the arcuate arteries, and decreased myometrial vascularity.

NuMA Overexpression in Epithelial Ovarian Cancer

Highly aneuploid tumours are common in epithelial ovarian cancers (EOC). We investigated whether NuMA expression was associated with this phenomenon. NuMA protein levels in normal and tumour tissues, ovarian cell lines and primary cultures of malignant cells derived from ovarian ascitic fluids were analysed by Affymetrix microarray analysis, immunoblotting, immunohistochemistry (IHC) and immunofluorescence (IF), with results correlated to associated clinical data. Aneuploidy status in primary cultures was determined by FACS analysis. Affymetrix microarray data indicated that NuMA was overexpressed in tumour tissue, primary cultures and cell lines compared to normal ovarian tissue. IHC revealed low to weak NuMA expression in normal tissues. Expression was upregulated in tumours, with a significant association with disease stage in mucinous EOC subtypes (p = 0.009), lymph node involvement (p = 0.03) and patient age (p = 0.04). Additional discontinuous data analysis revealed that high NuMA levels in tumours decreased with grade (p = 0.02) but increased with disease stage (p = 0.04) in serous EOC. NuMA expression decreased in late disease stage 4 endometrioid EOCs. High NuMA levels decreased with increased tumour invasion in all subtypes (p = 0.03). IF of primary cultures revealed that high NuMA levels at mitotic spindle poles were significantly associated with a decreased proportion of cells in cytokinesis (p = 0.05), increased binucleation (p = 0.021) and multinucleation (p = 0.007), and aneuploidy (p = 0.008). NuMA is highly expressed in EOC tumours and high NuMA levels correlate with increases in mitotic defects and aneuploidy in primary cultures.

Image guided biopsy in the management of cancer of the ovary

When used in the context of multidisciplinary team discussion, image guided biopsy using ultrasound (US) or computed tomography (CT) guidance is of value in planning management of women with suspected ovarian cancer and peritoneal carcinomatosis (PC) of uncertain aetiology. It is essential in women believed to have ovarian cancer but with poor performance status or with advanced disease believed beyond the scope of primary cytoreductive surgery for whom staging surgical pathology will not be obtained. It provides a site-specific primary tumour diagnosis in 93% of cases and it should replace diagnostic laparoscopy or laparotomy for this purpose. It allows provision of primary (neoadjuvant) chemotherapy based on a firm histological diagnosis. It is mandatory in women with a history of cancer whose metastases may mimic ovarian cancer (e.g. breast, GI tract, melanoma). More women with prior breast cancer who re-present with peritoneal cancer will have a new gynaecological primary than recurrence of their original primary tumour; the two options require radically different therapies. Finally it is a valuable problem solving tool in situations of diagnostic uncertainty, e.g. unusual imaging patterns of disease such as PC with bilateral solid ovarian masses or non-enlarged ovaries and with an unusual tumour marker profiles suggesting primary tumours outwith the ovary. The technique is simple, safe and effective and can be combined with palliative drainage of ascites at the same procedure.