Carlos Villena-Heinsen

Analysis of Vitamin D-receptor (VDR) and Retinoid X-receptor α in Breast Cancer

The expression of vitamin D-receptor (VDR) and retinoid X-receptor α (RXR-α) has been analysed immunohistochemically in benign (n = 62 and n = 5 respectively) and malignant (n = 228 and n = 15 respectively) breast tissue samples using a monoclonal antibody 9A7γ against VDR and a polyclonal antibody against RXR-α. A recently developed immunoreactive scoring method (IRS) was employed. The expression of VDR was detected at the RNA-level using the reverse transcriptase–polymerase chain reaction. A statistically significant higher expression of VDR at the protein level was seen in breast cancer compared with benign breast tissue, whereas at the mRNA level no visible differences in the expression of VDR were found. A higher expression of RXR-α was seen in breast cancer compared with benign breast tissue. Our findings indicate that breast tissue may be a new target organ for therapeutically applied vitamin D and retinoid analogues. VDR and RXR-α are upregulated at the protein level in breast carcinomas as compared to normal breast tissue, indicating a possibly increased sensitivity to therapeutically applied vitamin D analogues. New vitamin D analogues exerting less calcemic side effects may be promising new drugs for the treatment or chemoprevention of breast carcinomas as well as of precancerous breast lesions. Combination therapies of vitamin D and retinoid analogues with fewer side effects seen promising for the treatment of breast cancer.

Carcinosarcoma, endometrial intraepithelial carcinoma and endometriosis after tamoxifen therapy in breast cancer

The fourth case of heterologous mesodermal tumour of the uterine corpus, that developed, years following tamoxifen therapy for breast cancer in a postmenopausal woman with no previous pelvic irradiation, is presented with coincidental endometriosis and endometrial intraepithelial carcinoma. This coincidence after tamoxifen treatment appears to be an indication for the possible carcinogenic potency of tamoxifen.

Tamoxifen and proliferation of vaginal and cervical epithelium in postmenopausal women with breast cancer

OBJECTIVE The estrogenic effect of tamoxifen on vaginal and cervical epithelium in postmenopausal women with breast cancer is evaluated. STUDY DESIGN The tamoxifen group consisted of 92 postmenopausal breast cancer patients, the control group I of 30 postmenopausal women with breast cancer receiving no endocrine therapy and the control group II of 40 postmenopausal women without primary breast cancer taking no hormones. We determined the maturation index and the incidence of endocervical cell hyperplasia and metaplasia in cervical and vaginal smears. RESULTS The maturation index increased under tamoxifen within the first 24 months from 0.4011 before taking tamoxifen (n=56) to 0.6039 (n=138, P<0.0001). The maturation index in the group treated with tamoxifen was statistically significantly higher (P<0.0001) than in the control groups (control group I: 0.3975, P<0.0001; control group II: 0.4102, P<0.0001). Under therapy with tamoxifen endocervical cell hyperplasia (P=0.00156) and metaplasia (P=0.00123) appeared significantly more often. CONCLUSION An apparent increase not only of the incidence of endocervical cell hyperplasia and metaplasia but also of the maturation of the vaginal epithelium caused by the estrogenic effect of tamoxifen could be demonstrated.

Radioimmunoscintigraphy of ovarian tumours with technetium-99m labelled monoclonal antibody-170: first clinical experiences.

The recently developed technetium-99m-labelled monoclonal antibody-170 (MAb-170) was designed for diagnostic use in patients suffering from gynaecological adenocarcinoma. Following in vitro studies which showed immunoreactivity of this antibody to more than 90% of human adenocarcinomas, the present investigation was initiated to verify its usefulness for radioimmunoscintigraphy of ovarian tumours. Most of the 30 patients participating in this study underwent immunoscintigraphy prior to first-look surgery. Biokinetic evaluation in two patients showed a plasma half-time of 18.9 h (mean value,n = 2,r = 0.98) and a biexponential total body curve with values of 7.7 h and 17 days (r = 0.98). The mean 24-h urinary excretion was 12% of the injected dose. Radioimmunoscintigraphy using the MAb-170 recognised 12 of 13 cases of adenocarcinoma of the ovaries, corresponding to an overall sensitivity of 92.3% . Specificity was 94.1% (16/17). The calculation of accuracy yielded a figure of 93.3% (28/30). Of 33 known lesions, 26 were visualised successfully; thus the locoregional sensitivity was 78.8%. Of 29 benign tumour sites, 28 showed no evidence of tracer accumulation, corresponding to a locoregional specificity of 96.6%. The smallest lesion visualised was an adenocarcinoma of the corpus uteri with a diameter of 1.5 cm. Technetium-99m labelled MAb-170 is a promising new radiopharmaceutical for immunoscintigraphy of ovarian adenocarcinoma.

Immunohistochemical Analysis of DNA ‘mismatch-repair’ Enzyme Human Mut-S-Homologon-2 in Ovarian Carcinomas

The human Mut-S-Homologon-2 (hMSH-2) gene product is a member of a highly conserved family of proteins involved in postreplication mismatch repair. We have analysed hMSH-2 expression in normal ovarian tissue (n=15) and ovarian carcinomas (n=40). hMSH-2 protein was investigated immunohistochemically on frozen sections using a highly sensitive streptavidin–peroxidase technique and a specific mouse monoclonal antibody (clone FE11). A hMSH-2-immunoreactivity score (hMSH-2-IRS) for semiquantitative analysis of hMSH-2 expression is presented. In normal ovarian tissue, we only found weak nuclear immunoreactivity for hMSH-2 in 60%, while the remaining 40% were hMSH-2 negative (mean hMSH-2-IRS: 0.73; SD: ±0.70). All ovarian carcinomas analysed revealed moderate to strong nuclear immunoreactivity (mean hMSH-2-IRS: 8.05; SD: ±3.65). hMSH-2 staining was heterogeneous, with visual differences between individual tumour cells. Expression of hMSH-2 protein was consistently and strongly upregulated in tumour cells of ovarian carcinomas as compared to normal ovarian tissue. No statistically significant correlation in comparing the labelling patterns for hMSH-2 with the labelling patterns for Ki-67 (mean percentage of Ki-67 positive tumour cells: 25.88%; SD: ±18.43) was observed in ovarian carcinomas. Furthermore, no statistical significant correlations between hMSH-2-IRS and histological grading (p=0.47), histological type of carcinoma (p=0.706) or FIGO-classification (p=0.054) were found. Our findings indicate that (a) hMSH-2 is expressed in normal human ovarian tissue, (b) expression of hMSH-2 is increased in ovarian carcinomas, (c) expression of hMSH-2 may be of importance for the genetic stability of ovarian carcinomas in vivo, (d) hMSH-2 mutations may not cause microsatellite instability in ovarian carcinomas, (e) hMSH-2 may contribute to mechanisms responsible for resistance to anticancer drugs.

Monoclonal antibody MAb-170 for immunoscintigraphic detection of ovarian tumors.

OBJECTIVE The technetium Tc 99m-labeled monoclonal antibody MAb-170 was designed for diagnostic use in patients with gynecologic adenocarcinoma. Our investigation was initiated to verify its usefulness for radioimmunoscintigraphy of ovarian tumors. STUDY DESIGN Most of the 82 patients participating in this study underwent immunoscintigraphy before first-look surgery. RESULTS Radioimmunoscintigraphy recognized 36 of 41 patients with adenocarcinoma of the ovaries, corresponding to an overall sensitivity of 88%. Specificity was 90% (38/42). The calculation of accuracy gave a result of 89% (74/83). Of 110 known lesions, 92 were visualized successfully; thus the local-regional sensitivity was 84%. Of 160 benign tumor sites, 154 showed no evidence of tracer accumulation, corresponding to a local-regional specificity of 96%. The smallest lesion visualized was an adenocarcinoma of the corpus uteri with a diameter of 1.5 cm. CONCLUSION The monoclonal antibody MAb-170 is a promising radiopharmaceutical for immunoscintigraphy of ovarian adenocarcinoma.

Expression of Transglutaminase K in Normal Cervix Tissue and Cervix Carcinomas

The localization and expression of transglutaminase K has been investigated immunohistochemically in normal cervix tissue (n=15) and in cervix carcinomas (n=23). The distribution of the transglutaminase K was compared with the staining patterns of cytokeratin 10, Ki-67, p53, and oestrogen and progesterone receptors in these tumours. Weak to strong membrane-bound immunoreactivity for transglutaminase K was detected in almost all cervix carcinomas analyzed. The immunostaining was heterogeneous, with visual differences between individual tumour cells. 66.7% of normal cervix tissues revealed no immunoreactivity for the transglutaminase K. In normal cervix tissue, the immunoreactivity was confined to upper cervix layers, predominantly to the superficial and intermediate cell layers. The intensity of both the immunostaining and the number of transglutaminase K-positive cells were upregulated in cervix carcinomas as compared to normal cervix tissue. When the coexpressions of transglutaminase K with markers of proliferation and differentiation were analyzed, no statistically significant correlation was found. Our findings indicate that (1) transglutaminase K is upregulated at the protein level in cervix carcinomas as compared to normal cervix tissue; (2) upregulation of the transglutaminase K in cervix carcinoma is not exclusively induced by alterations of epithelial differentiation or proliferation, but by different, unknown mechanisms; and (3) upregulation of transglutaminase K in cervix carcinomas may play an important role for the regulation of tumour invasive properties by modulating cell–cell interactions.

Validity of the minimal resistance index for discrimination between benign and malignant breast tumours

We investigated the validity of the flow parameter minimal resistance index (min RI) for discrimination of breast tumours. Colour and spectral Doppler sonography was performed on 114 patients. An increase in number of tumour vessels was paralleled by a significant drop of the minimal (min) RI (p=0.004) and increase of the maximal (max) RI (p=0.03) while mean RI was not influenced. The present results question the validity of min RI as parameter for discrimination of breast tumours. Min RI does not represent the actual flow resistance.

Radioimmunoscintigraphy of Ovarian Tumours with Tc-99m Labelled Monoclonal Antibody-170

The present publication reflects our first experiences using the Tc-99m labelled monoclonal antibody MAb-170 for diagnostic use in patients with ovarian tumours. The collective included 10 patients suspected to have ovarian carcinoma. The results showed a sensitivity of 100 percent, the specificity was 100 % for adenocarcinoma and 71 % for ovarian carcinoma. In conclusion Tc-99m MAb-170 is a promising radiopharmaceutical for the detection of ovarian carcinoma.

Rhenium-186 Labelled MAb-170: A Suitable Agent for Radioimmunotherapy of Ovarian Carcinoma?

For biokinetic and dosimetry studies the Tc-99m-labelled MAb-170 was administered intraperitoneally in four patients. Assuming equal biodistribution for the Re-186- and Tc-99m-tagged antibody the 48 hours-measurement of whole-body scintigraphy, blood activity concentration and urinary excretion gave a value of 0.35 Gy/370 MBq for bone marrow dose. These results confirm that a RIT with Re-186 MAb-170 might be feasible with activities of up to 3.7 GBq.