Basement membranes in cervical cancer: relationship to pelvic lymph node metastasis and prognosis

Alterations in the expression and activity of extracellular matrix components in HPV-associated infections and diseases

Infection with human papillomaviruses is associated with a series of benign and malignant hyperproliferative diseases that impose a heavy burden on human populations. A subgroup of mucosal human papillomavirus types are associated with the majority of cervical cancers and a relevant fraction of vulvar, vaginal, anal, penile and head and neck carcinomas. Human papillomaviruses mediate cell transformation by the expression of two pleiotropic oncoproteins that alter major cellular regulatory pathways. However, these viruses are not complete carcinogens, and further alterations within the infected cells and in their microenvironment are necessary for tumor establishment and progression. Alterations in components of the extracellular matrix for instance, matrix metalloproteinases and some of their regulators such as tissue inhibitors of metalloproteinases, have been consistently reported in human papillomaviruses-associated diseases. Matrix metalloproteinases function by remodeling the extracellular matrix and alterations in their expression levels and/or activity are associated with pathological processes and clinical variables including local tumor invasion, metastasis, tumor relapse and overall patient prognosis and survival. In this review we present a summarized discussion on the current data concerning the impact of human papillomavirus infection on the activity and expression of extracellular matrix components. We further comment on the possibility of targeting extracellular matrix molecules in experimental treatment protocols.

Immunophenotypic alteration of the stromal component in minimal deviation adenocarcinoma ('adenoma malignum') and endocervical glandular hyperplasia: a study using oestrogen receptor and alpha-smooth muscle actin double immunostaining

AIMS

To define the phenotypic alteration of the stromal component in association with destructive invasion which is a crucial feature in distinguishing minimal deviation adenocarcinoma (MDA) from benign endocervical glandular lesions.

METHODS AND RESULTS

We studied endocervical glandular hyperplasias including non-specific-type (NEGH) (n = 3) and lobular-type (LEGH) (n = 8), and minimal deviation adenocarcinoma (MDA) (n = 11), well-differentiated endocervical adenocarcinoma of usual-type (WDA) (n = 11), and adenocarcinoma in situ (AIS) (n = 6) of the cervix, by double immunostaining for oestrogen receptor (ER) and alpha-smooth muscle actin (alpha-SMA) using peroxidase- and alkaline phosphatase-polymer methods, respectively. Glands in NEGH invariably showed nuclear staining for ER, with surrounding ER+/alpha-SMA- stromal cells, whereas LEGH also harboured ER+/alpha-SMA- spindle cells, but lacked nuclear staining for ER in constituent glands. In contrast, both WDA and MDA displayed accompanying stroma rich in alpha-SMA+ spindle cells in close vicinity to the infiltrating neoplastic glands, with only occasional weakly ER+ stromal cells. WDA tended to contain more alpha-SMA+ cells. The distribution of alpha-SMA+ cells was periglandular (6/11), patchy (6/11), and/or diffuse (4/11) in WDA, whereas in MDA it was periglandular (11/11) and/or patchy (8/11). AIS was surrounded by ER+/alpha-SMA- stromal cells. All cases of WDA, MDA, and AIS lacked nuclear staining for ER.

CONCLUSIONS

Both MDA and WDA can be distinguished from LEGH and NEGH by identifying surrounding alpha-SMA+ stromal cells and the absence or decreased number of ER+ cells, possibly as a result of the desmoplastic reaction with myofibroblasts replacing pre-existing ER+ stromal cells. In particular, the periglandular distribution of these alpha-SMA+ stromal cells can be a clue suggesting destructive stromal invasion in cases of MDA, although occasional glands may lack these cells.

Accuracy of pelvic examination in the assessment of patients with operable cervical cancer

OBJECTIVE

The purpose of this study was to determine whether pelvic examination identifies factors that suggest the need for radiotherapy after radical hysterectomy for cervical cancer.

STUDY DESIGN

This was an observational study that was conducted from July 1, 2000 through December 31, 2002 that comprised 67 patients with stage 1B-2A cervical cancer who underwent primary surgical treatment. Assessments that were made on pelvic examination were compared with pathologic findings. Data were analyzed with the use of descriptive statistics, calculation of sensitivities, specificities, positive and negative predictive values, and determination of odds ratios.

RESULTS

The overall spectrum of small to large tumors (<1-8 cm) and cervices (2.5-8 cm) correlated well with examination (r=0.77-0.88). The accuracy of examination was approximately 50% for tumor diameter (+/-25%), 85% for cervical diameter (+/-25%), 80% for outer-third invasion, 80% for endophytic growth, and 90% for vaginal involvement. The likelihood for adjuvant radiotherapy had a significant association with the number of at-risk examination variables that were present.

CONCLUSION

For women who undergo radical hysterectomy for stage 1B to 2A cervical cancer, the presence of multiple high-risk factors that are found on pelvic examination is associated significantly with indications for adjuvant postoperative radiotherapy.

Expression of matrix proteins in uterine cervical neoplasia using immunohistochemistry

OBJECTIVE

Neoplastic cells of various tumors are capable of modifying extracellular matrix, and can reduce basement membrane components and express matrix proteins and mRNA. Findings in cervical cancer cells have been consistent concerning their ability to reduce basement membrane, but there is a lack of consensus concerning the expression of matrix proteins in the neoplastic cells. We have investigated the expression of matrix proteins in the subepithelial basement membrane, in blood vessels and in the epithelial cells using immunohistochemistry.

STUDY DESIGN

A total of 49 cases, including normal cervix, Cervical Intraepithelial Neoplastia (CIN) grades, I, II and III, and invasive squamous cell carcinoma, were stained for fibronectin (FN), laminin (LN) and collagen IV (C IV) and analyzed by immunohistochemistry. Subepithelial and peritumoral basement membrane staining for C IV was scored as 0, 1, 2 or 3 (0, absent; 1, weak and discontinuous; 2, weak or discontinuous; 3, strong and diffuse). Vascular basement membrane staining by all three markers was interpreted as positive or negative. Staining of normal epithelium, CIN lesions and invasive carcinoma cells was evaluated with all three markers.

RESULTS

Subepithelial basement membrane staining was graded as score = 3 in all normal cervices, in contrast to 9/10, 2/10, 1/10 and 0/9 cases of CIN I, CIN, II, CIN III and invasive carcinoma, respectively. Remaining cases showed variable degrees of basement membrane loss. In 6/10 CIN III cases and 8/9 carcinomas, staining was absent (score = 0). Blood vessels stained positive for FN, LN and C IV in all cases studied. Epithelial cells were LN-positive in only one case of CIN II and FN-positive in only two cases of CIN III. Conversely, 3/9 carcinomas were LN-positive, 6/9 were FN-positive and 2/9 were C IV-positive, including two cases positive for all three markers. Staining pattern was cytoplasmic, mainly in the periphery to tumor islands.

CONCLUSIONS

Invasive squamous cell carcinomas of the cervix are capable of expressing matrix proteins that are usually absent in normal squamous cervical cells or preinvasive lesions. Secretion or degradation of these proteins could facilitate tumor invasion of stroma and vessels. In addition, basement membrane dissolution becomes pronounced in CIN II-III lesions, being complete in most invasive carcinomas, probably reflecting the ability of pre-invasive neoplastic cells to degrade basement membrane components with metalloproteases.