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H E Schaafsma

Publications and source records attributed to H E Schaafsma.

At least 37 records · Page 2Linked to original sources
PubMed1993

Decreased E-cadherin immunoreactivity correlates with poor survival in patients with bladder tumors.

E-cadherin, an intercellular adhesion molecule, has been shown to behave like an invasion suppressor gene in vitro. This may explain the inverse relation between expression of E-cadherin and tumor grade that was found in certain cancers. We therefore examined E-cadherin expression in bladder cancer samples from patients with known clinical follow-up. Forty-nine snap-frozen specimens (24 superficial and 25 invasive tumors) and 4 samples of normal urothelium were retrospectively analyzed with anti-E-cadherin monoclonal antibodies. In normal urothelium E-cadherin is expressed homogeneously with a typical membranous staining at cell-cell borders. Decreased expression is found in 5 of 24 superficial tumors and in 19 of 25 invasive cancers. Completely negative tumors are infrequent (4 cases). Most of the time a heterogeneous staining, which may correspond to an unstable E-cadherin expression during tumor development, is seen. Decreased E-cadherin expression correlates with both increased grade and stage (chi 2 = 9.5, P < 0.01, and chi 2 = 14.9, P < 0.005, respectively). More importantly, abnormal E-cadherin expression correlates with shorter survival (log rank test: chi 2 = 16.5, P < 0.001). In keeping with its in vitro invasion suppressor function, decreased E-cadherin expression correlates with the clinical aggressiveness of bladder tumors. This is the first report of E-cadherin as a marker with prognostic value. This parameter must now be tested in a large prospective study to assess its precise clinical relevance.

Adult↗
PubMed1993

Increased expression of cytokeratins 8, 18 and vimentin in the invasion front of mucosal squamous cell carcinoma.

The immunohistochemical expression patterns of cytokeratins 8 and 18 and vimentin were examined in frozen sections of 120 human mucosal squamous cell carcinomas with special emphasis on the topological distribution in the tumour. This was done in order to evaluate in squamous cell carcinoma a particular expression pattern observed recently by us in transitional cell carcinoma of the urinary tract and designated as an 'interface phenomenon'. This phenomenon implying maximum expression of cytokeratins 8 and 18 at the tumour front, and to a lesser extent also in areas of intratumorous stroma contact, was also found in about 50 per cent of the squamous cell carcinomas examined. It was even found for vimentin, which contrasted with transitional cell carcinoma. The percentages of occurrence of the phenomenon varied for the different sites of origin of the tumour. Tumour grade did not influence the results. These findings further support the idea that invasive carcinoma cells interacting with the stromal micro-environment display a characteristic intermediate filament phenotype that deviates from the pattern expected on the basis of their direction of differentiation. These changes might reflect phenotype involved in invasive, migrating, and proliferating activities.

Carcinoma, Squamous Cell↗
PubMed1993

The rat bladder tumor model system RBT resembles phenotypically and cytogenetically human superficial transitional cell carcinoma.

A cohort of 300 ACI rats was kept under standard laboratory conditions. After 30 months or upon natural death, complete autopsy was performed. In the genitourinary tract four kidney and five bladder tumors were found. Two of these bladder tumors, RBT323 and RBT157, are serially transplantable. In the fifth transplant generation the RBT323 tumor becomes metastatic to the lungs in more than 90% of animals. The metastatic ability of the RBT157 tumor changes from low to intermediate (50% of the rats have lung metastases) in the fourth passage. Histologically, the initial passages of the RBT323 and 157 tumors are grade II transitional cell carcinoma (TCC). The histological pattern of the RBT157 tumor remains essentially unchanged, whereas the RBT323 tumor progresses to a grade III tumor in the third passage. Electron microscopical studies reveal oblong elliptical and round vesicles lined by an asymmetrical unit membrane in the tumor cells, which stresses the urothelial origin of the tumors. Immunohistochemically both tumors show expression of cytokeratin 5, 7, 8 and 18. The progression of the tumors to a metastatic phenotype, however, is not associated with a specific change in the morphological characteristics. Cytogenetic analysis shows that both tumors are peridiploid with few marker chromosomes. Interestingly, both of these independently arising tumors exhibit a loss of chromosome 5. Rat chromosome 5 is syntenic to the major portion of human chromosome 9 (p23-qter). Loss of chromosome 9 is a cytogenetic trait of human superficial TCC, hence the RBT model is also in cytogenetic respect similar to human TCC.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

A randomised prospective study comparing intravesical instillations of mitomycin-C, BCG-Tice, and BCG-RIVM in pTa-pT1 tumours and primary carcinoma in situ of the urinary bladder. Dutch South-East Cooperative Urological Group.

We compared intravesical instillations with mitomycin-C (MMC), Bacillus Calmette-Guerin (BCG) Tice, and BCG-RIVM in patients with pTa-pT1 papillary carcinoma and primary carcinoma in situ (CIS) of the bladder. Nine instillations with MMC were given or 6 weekly instillations with BCG. Early recurrences were treated with additional instillations. For toxicity and efficacy 437 patients were evaluated with a median follow-up of 32 months (range 12-56). Drug-induced and bacterial cystitis were the most frequent side-effects. The number and severity of side-effects (chi 2 test) were comparable in both BCG groups, but were significantly less in the MMC group for drug-induced cystitis (P = 0.009), other local side-effects (P = 0.004) and systemic side-effects (P < 0.001). The disease-free percentage (log-rank test) showed no significant difference for the three arms for papillary tumours (P = 0.08), nor the CIS (P = 0.20), although for CIS numbers are small. Additional instillations did not influence toxicity or efficacy.

Administration, Intravesical↗
PubMed1993

Neoadjuvant therapy in prostate cancer--is it of any use?

Since 1941, when the androgen dependency of prostatic carcinoma was described first, the question whether neoadjuvant hormone manipulation enhances surgical curability has been of actual importance. With the availability of reversible luteinizing hormone-releasing hormone analogues and non-steroidal antiandrogens, interest in preoperative hormonal manipulation has recently been reinnovated. An overview of the published, sometimes conflicting clinical and pathological studies evaluating the value of neoadjuvant hormone manipulation is given. We conclude that further well-controlled clinical investigations comparing downstaging and downgrading percentages, percentages of local control and survival are needed to prove the benefit of neoadjuvant treatment in patients with locally confined prostatic carcinoma.

Androgen Antagonists↗
PubMed1992

Colocalization of basal and luminal cell-type cytokeratins in human prostate cancer.

In the epithelium of secretory acini of the prostate two different cell types can be discriminated on the basis of localization, morphology, and degree of differentiation, the luminal and basal cells. The possibility of a developmental relationship between basal and luminal cells has been a subject of interest in several studies. According to the stem cell model at least three cell types, i.e., stem, amplifying, and transit cells, can be discriminated in the epithelium of prostate secretory acini. We previously reported that in the process of degeneration and regeneration in normal rat prostate a population of cells could be identified as candidates for the amplifying cells. These cells showed a keratin expression profile intermediate between those of basal and luminal cells. We now show, by using keratin antibodies, that also in normal human prostate at least three subpopulations of cells can be identified, one of them putatively representing amplifying cells as defined in the stem cell model. Furthermore, these antibodies were used to obtain a better insight into the different cell types involved in the etiology and progression of prostatic carcinoma. Both primary and hormone-independent prostatic tumors were investigated. Our results indicated that the candidate stem cell population was absent in prostatic carcinoma. Unlike earlier reports on the unique presence of cells with luminal characteristics in prostatic carcinoma, we identified also a population of cells coexpressing basal and luminal cell-type cytokeratins in primary and hormone-independent prostatic carcinoma. Since amplifying cells are defined in the stem cell model as precursors of transit (luminal) cells in the hierarchical pathway of prostatic epithelium differentiation, we postulate that on the basis of the keratin expression profile this subpopulation is most likely the target for neoplastic transformation.

Antibodies, Monoclonal↗
PubMed1992

Expression of the cellular adhesion molecule E-cadherin is reduced or absent in high-grade prostate cancer.

E-cadherin is a Ca(2+)-dependent cell adhesion molecule which plays an important role in normal growth and development via mediation of homotypic, homophilic cell-cell interaction. Recent studies suggest that E-cadherin may be important in neoplastic progression as well, particularly as a suppressor of invasion. We have previously demonstrated that the invasive phenotype of rat prostate cancer cells is associated with the decreased expression of E-cadherin (M. J. G. Bussemakers, R. J. A. Van Moorselaar, L. A. Giroldi, T. Ichikawa, J. T. Isaacs, F. M. J. Debruyne, and J. A. Schalken, Cancer Res., 52:2916-2922, 1992). This is of particular interest, since the locus to which the human E-cadherin gene is mapped is frequently involved in allelic loss in prostate cancer (B. S. Carter, C. M. Ewing, W. S. Ward, B. F. Treiger, T. W. Aalders, J. A. Schalken, J. I. Epstein, and W. B. Isaacs, Proc. Natl. Acad. Sci. USA, 87:8751-8755, 1990; U. S. Bergerheim, K. Kunimi, V. P. Collins, and P. Ekman, Genes, Chromosomes Cancer, 3: 215-220, 1991). Impaired E-cadherin function is likely to be associated with aberrant expression of the protein. We therefore analyzed E-cadherin expression in situ by immunohistochemistry in nonmalignant and malignant specimens of human prostatic tissue. Of 92 tumor samples of either primary or metastatic deposits of prostate cancer, 46 had reduced or absent E-cadherin staining when compared to nomalignant prostate, which uniformly stained strongly positive. There was a statistically significant correlation between the decreased expression of E-cadherin and loss of tumor differentiation. Additionally, certain tumors within a histologically similar group could be distinguished by the presence of mixed populations of E-cadherin-negative and -positive cells. The percentage of tumors with aberrant E-cadherin staining increased when clinically localized tumors were compared to either tumors with extensive local progression or metastatic deposits of prostate cancer, suggesting a correlation between loss of E-cadherin and tumor progression. Taken together, these findings suggest that further exploration of E-cadherin as a candidate invasion suppressor molecule in human prostate cancer is warranted.

Cadherins↗
PubMed1992

Inflammatory pseudotumor of the subglottis.

A rare case of an idiopathic inflammatory pseudotumor of the larynx is described. Management consisted of midline vertical thyrotomy with anterior cricoid splitting, excision of the subglottic tumor and temporary stenting of the lumen with a siliconized tube. While these lesions are benign, the therapeutic consequences of misdiagnosis can be serious. Effective treatment consists of surgical excision, which results in a permanent cure.

Female↗
PubMed1992

Myospherulosis in the operated temporal bone.

Myospherulosis is an unusual foreign-body reaction occurring in tissues exposed to petrolatum-based products. Histopathologically this disorder is characterized by the presence of large and small tissue spaces containing amorphous debris and peculiar sac-like structures enclosing numerous brown spherical bodies. A rare case of myospherulosis of the middle ear and mastoid is presented and the literature is reviewed.

Adult↗
PubMed1992

Immunohistochemical localization of basement membrane type VII collagen and laminin in neoplasms of the head and neck.

The distribution pattern of the basement membrane components type VII collagen and laminin, was studied immunohistochemically in normal human head and neck tissues and in a series of benign and malignant tumours from the same site. Using monoclonal antibodies, a basement membrane containing type VII collagen and laminin could be demonstrated beneath the epithelial cell layer in 16 normal head and neck tissues from different localizations. Unlike type VII collagen, laminin was also abundantly present around blood vessels and muscle fibres. With respect to 42 squamous cell carcinomas studied, type VII collagen and laminin were present in basement membranes surrounding small and large tumour fields, independent of the tumour grade. Type VII collagen was demonstrated in the cytoplasm of tumour cells in 36% of the cases, while the antibody to laminin displayed a basement membrane staining pattern mainly. Both antibodies showed a staining gradient in more than half of the cases, with strong staining in the centre of the tumour and weakening of the staining towards the tumour periphery. In a series of 22 salivary gland tumours consisting of 19 pleomorphic adenomas and three adenoid cystic carcinomas, the distribution pattern of type VII collagen and laminin was very heterogeneous. Laminin was present in 17 and type VII collagen in 10 of 19 cases of pleomorphic adenoma, mostly scattered throughout the tumour fields. In the tumours positive for type VII collagen areas with little or no positivity were also found. A correlation between type VII collagen positivity and the presence of basal cell keratin 14 positivity was noticed in the majority of cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Basement Membrane↗
PubMed1992

Laminin and type VII collagen distribution in different types of human lung carcinoma: correlation with expression of keratins 14, 16, 17 and 18.

The expression patterns of basement membrane components and keratin intermediate filament proteins were studied in normal human bronchial epithelium and 56 lung carcinomas using monoclonal antibodies to laminin, type VII collagen and the individual keratins 14, 16, 17 and 18. In normal lung, laminin and type VII collagen were present between the epithelium and the lamina propria of bronchi and bronchioles. Keratin 14 was expressed in the basal cells, keratin 17 in the basal and some suprabasal cells and keratin 18 in the columnar cells of the bronchi and bronchioles. Keratin 16 was not present in normal bronchial epithelium. Laminin was found in all subtypes of lung carcinoma, but type VII collagen was present only in squamous cell carcinomas, where it showed a reduction in expression with decreasing differentiation. Type VII collagen was not identified in adenocarcinomas, small cell carcinomas or carcinoids. Antibodies to basal cell keratins 14 and 17 also displayed positivity only in squamous cell carcinomas, although no correlation with the degree of differentiation could be observed. Keratin 16 appeared to be a marker of the squamous phenotype, rather than of hyperproliferation. The keratin 18 marker for columnar epithelial cells showed a reaction pattern opposite to that of the basal cell keratins, being extensively present in adenocarcinomas, small cell carcinomas and carcinoids, with less expression in squamous cell carcinomas. This study shows a correlation between the presence of type VII collagen and the basal cell keratins 14 and 17, and a negative correlation between these components and keratin 18. These findings are likely to be useful in identifying lung cancer subtypes.

Adenocarcinoma↗
PubMed1992

Establishment and characterization of five new human renal tumor xenografts.

Ten different human renal cell carcinoma (RCC) primary tumors were xenografted into BALB/c nu/nu mice. Five of the tumors (NU-10, NU-12, NU-20, NU-22, and NU-28) gave rise to serially transplantable tumors that were further characterized. Histology, DNA index, immunohistochemical characteristics, growth rate, and clonogenic potential were followed from primary tumor to the 5th to 15th transplant passage. Only one of the tumors (NU-20) showed remarkable instability for all tested parameters in the first five transplant passages. Histology of the other tumors was essentially the same to the histology of the primary tumors, although differences between human and host-derived vessels were apparent. DNA index values in general showed a trend toward an aneuploid character of the xenografts. Immunohistochemical analyses showed a loss of intensity of staining but a concomitant rise in the fraction of positively staining cells with antibodies against cytokeratins, vimentin, tumor-associated antigens, and human leukocyte antigen (HLA) class I antigens. Human leukocyte antigen class II antigen expression showed a loss of intensity as well as a decrease in the fraction of positive cells. Tumor doubling time was lowest in transplant passage number 0, and stable growth was noticed in transplant passages 1 through 4. Clonogenic potential of four of the lines was higher for the xenografts than for the primary tumors. The authors conclude that, on xenografting, histologic characteristics of the primary tumor are essentially conserved. Progression in the first transplant passages, however, results in tumors with a more aggressive character.

Adolescent↗
PubMed1991

Extramedullary plasmacytoma of the urethra: a case report.

Extramedullary plasmacytomas are uncommon manifestations of plasma cell neoplasms, which occur rarely in the urinary tract. We report to our knowledge the third case of primary IgA plasmacytoma of the urethra. Diagnosis, therapy and followup with magnetic resonance imaging are presented.

Adult↗
PubMed1991

Cytokeratin expression patterns in metastatic transitional cell carcinoma of the urinary tract. An immunohistochemical study comparing local tumor and autologous metastases.

The cytokeratin (CK) expression patterns of local, ie, primary or recurrent, high-grade-malignant transitional cell carcinomas (TCCs) of the human urinary tract and autologous lymphogenic and hematogenic metastases (n = 33) were compared. Special attention was paid to CK expression in the tumor invasion front and other areas where tumor-stroma interaction occurred to visualize cell populations with a metastatic phenotype. For this purpose, polypeptide-specific monoclonal antibodies to CKs 4, 7, 8, 10, 13, 14, 16, 17, 18, and 19 were used, employing the immunoperoxidase method. Results show that: 1) An increased expression of CK8 and CK18 is seen in the TCC tumor cells at the interface with peritumoral stroma in the tumor invasion front and with intratumoral stroma ('interface phenomenon'). Other than reflecting a quantitative change, this phenomenon might be explained by unmasking of CK8 and CK18 epitopes occurring in these regions. 2) Although in general the expression of CK13 in local TCC is decreased with increase of histopathologic parameters for progression, ie, grade and stage, an extensive proportion of CK13-positive tumor cells still can be found in some TCCs, even in metastases. 3) Morphologically recognizable types of aberrant differentiation in TCC, i.e., pseudosarcomatous or squamous differentiation and marked loss of differentiation, show altered expression of many of the CKs studied.

Carcinoma, Transitional Cell↗
PubMed1991

Distribution patterns of type VII collagen in normal and malignant human tissues.

The distribution of basement membrane type VII collagen was detected immunohistochemically and compared in normal human organs and their neoplastic derivatives using monoclonal antibody LH7.2. In normal tissues, type VII collagen was found to be restricted to the basement membrane surrounding or underlying combined epithelia, such as those lining breast, prostate, and bronchus, which are composed of a basal and luminal cell layer, and stratified epithelia, such as larynx, esophagus, trachea, vagina, ectocervix, and epidermis. No type VII collagen was found in the "simple' epithelia lining the major part of the gastrointestinal tract (GI) tract, such as liver, stomach, and intestine, or around blood vessels, muscle, and nerve fibers, which are surrounded, however, by a basement membrane containing type IV collagen and laminin. When tested in benign and malignant local tumors, antibody LH7.2 showed staining patterns partly similar to those observed in the corresponding normal tissues. This resulted in a well-circumscribed positive reaction around ducts in carcinomas in situ of the breast, in benign prostate tumors, in pleomorphic adenomas, and in a negative reaction in tumors of the GI tract. Furthermore type VII collagen was predominantly seen in carcinomas with a squamous differentiation, such as squamous carcinomas of the lung, head and neck, vulva, and vagina. These results indicate that the presence of type VII collagen in malignant tumors is correlated with (squamous) differentiation rather than with the origin of the tumor. With tumor progression, an increased presence of type VII collagen, as compared with normal urinary bladder, was found in infiltrating transitional cell carcinomas. Thus, although in general invasive and metastatic tumors do not express extensively type VII collagen, exceptions to this rule exist in bladder cancer, squamous carcinomas of the lung, tumors of the head and neck region, female genital tract tumors, and in some adenocarcinomas of the breast.

Breast Neoplasms↗
PubMed1990

Distribution of cytokeratin polypeptides in human transitional cell carcinomas, with special emphasis on changing expression patterns during tumor progression.

The expression of cytokeratin (CK) polypeptides was studied in 59 transitional cell carcinomas (TCC) of the urinary tract of different grade and stage. Using a panel of 14 polypeptide-specific monoclonal CK-antibodies we identified immunohistochemically 8 different CKs separately, ie, CKs 4, 7, 8, 10, 13, 14, 18, and 19, while in immunoblotting studies CK5 expression was detected indirectly by using the antibody RCK102, recognizing CK5 + 8. In low-grade TCCs (G1-G2), the CK distribution was comparable to that in normal urothelium, however with a variable expression of CK13 in the different tumors and a uniform distribution of CK7. In higher-grade TCCs (G3), a decrease in CK13 expression was observed, particularly in the areas of muscle invasion. Furthermore, the appearance and increasing expression of CK14 (not present in normal urothelium or G1 TCCs) with higher grade and stage was striking. With tumor progression changes in epitope configurations of CK8 and CK18 were detected, as concluded from immunohistochemical assays with the panel of monoclonal antibodies for each of these two CKs. In extreme cases this resulted in differential staining patterns of the invasive and noninvasive components within one tumor. In 7 of 32 G3 TCCs, some of which showed areas with evident squamous differentiation, a decrease in the expression of CK7 and/or CK8 was seen. We conclude that tumor progression in TCCs is associated with discrete changes of CK expression, which can be detected using monoclonal antibodies.

Antibodies, Monoclonal↗