Preferential activation of the epidermal growth factor receptor in human colon carcinoma liver metastases in nude mice.

Increased epidermal growth factor receptor (EGF-R) gene expression and functional protein levels correlate with the metastatic potential of human colon carcinoma (HCC) cells in nude mice. The purpose of this study was to determine whether the production of liver metastases by HCC cells depends on the EGF-R activation status and whether different organ microenvironments influence this activation. Using two independent monoclonal antibodies specific for the activated (i.e., tyrosine-phosphorylated) EGF-R, increased immunoreactivity was observed in HCC cells growing as metastatic lesions in the livers of athymic nude mice. Staining was observed throughout these lesions, both peripherally and centrally. In contrast, little or no immunoreactivity for activated EGF-R was observed in primary tumors growing orthotopically in the cecum or ectopically in the subcutis of nude mice. Immunohistochemistry for total EGF-R levels (irrelevant of activation status) demonstrated similar levels of immunoreactivity in HCC tumors growing in the cecum, subcutis, or liver of nude mice, indicating that total EGF-R levels are not altered after growth in these different microenvironments. Controls included immunohistochemistry for total and activated EGF-R levels in HCC cells growing in vitro under serum-free or EGF-stimulated conditions and A431-epidermoid carcinoma growing in nude mice. Western blot analyses confirmed the specificity of the antibodies for the activated EGF-R. These results suggest that the production of liver metastasis by HCC cells depends in part on the response of tumor cells to organ-derived growth factors and hence the activation of specific cell surface tyrosine kinase receptors.

Use of aromatase inhibitors in postmenopausal women with advanced breast cancer.

Surgeons have been involved in the management of metastatic breast cancer since the technique of ovarian ablation was introduced in 1896. However, as newer hormonal and chemotherapeutic regimens were developed, drug therapy gradually replaced surgery as the preferred treatment for metastatic breast cancer. Thus, management of metastatic breast cancer has largely shifted from surgeons to medical oncologists. Advances in hormonal pharmacology have placed hormonal therapy alongside surgery and radiation therapy as a standard treatment option for women with advanced breast cancer. The purpose of this article is to update surgeons on the current use of hormonal agents for treatment of advanced breast cancer in postmenopausal women, and to review the aromatase inhibitors, a new line of hormonal agents for the treatment of advanced breast cancer.

Annexin II marks astrocytic brain tumors of high histologic grade.

Annexin II is highly expressed in glioblastoma multiforme [Reeves, S. A.; Chavez-Kappel, C.; Davis, R.; Rosenblum, M.; Israel, M. A. Developmental regulation of annexin II (lipocortin 2) in human brain and expression in high grade glioma. Cancer Res. 52:6871-6876; 1992] and is a likely second messenger in mitogenic pathways known to be important for the growth of these tumors. We have examined tumor tissue from patients diagnosed with low-, intermediate-, or high-grade astrocytic tumors for expression of annexin II by immunohistochemistry, and found that annexin II levels varied significantly among these three tumors (P < 0.0005). Levels were highest in glioblastoma multiforme, intermediate in anaplastic astrocytomas, and lowest in astrocytomas. In contrast to the usual cytoplasmic localization of annexin II, distinct nuclear staining was found in many of the specimens. Reactive astrocytes found in gliotic brain also stained with anti-annexin II antibody. We examined matched specimens for a correlation between annexin II staining intensity and the bromodeoxyuridine labeling index and found that, while tumors with the most intense annexin II staining had highest bromodeoxyuridine labeling indexes, there was not a strong association between these two parameters. The association between annexin II staining and histologic grade in astrocytic malignancies indicates that annexin II may be an important marker of high-grade glial tumors, and suggests that this marker may be useful for the pathologic classification of glial tumors and the clinical evaluation of brain tumor patients.

Genitourinary malformations associated with agenesis of the corpus callosum.

Agenesis of the corpus callosum is an infrequent congenital anomaly that occurs in partial or complete forms, and is frequently associated with other craniofacial and skeletal abnormalities. An increased association with genitourinary abnormalities has not been previously defined. We reviewed the records of 22 boys and 11 girls with agenesis of the corpus callosum. Of the patients 18 had complete radiological or necroscopic evaluation and 15 had physical examinations as the sole means of evaluation. Renal anomalies were the most frequent genitourinary abnormalities identified in these children, although ureteral, genital and bladder abnormalities were also encountered. There was an exceptionally high incidence of undescended testes (23%), approximately 20-fold greater than the frequency in the normal population, possibly resulting from hypothalamic insufficiency associated with midline cranial defects. We suggest, therefore, that all patients with agenesis of the corpus callosum should be thoroughly evaluated with bladder and renal ultrasound studies to rule out any genitourinary abnormalities. Male patients with agenesis of the corpus callosum and undescended testes should undergo hypothalamic/pituitary axis testing.

Affinity isolation of transcriptionally active DNA.

Chicken erythrocyte nuclei were nick translated with the chemically cleavable biotinylated nucleotide, Bio-12-SS-dUTP. DNA was purified, digested with restriction endonucleases, and applied to an avidin-agarose affinity column. Seventy percent of the nick translated DNA bound to the column. This DNA was recovered from the column by chemical cleavage of the linker arm joining biotin to the DNA. Dot hybridization analysis of this DNA revealed a significant enrichment of the alpha-D-globin gene. This result suggests an approach to isolate transcriptionally active genes.

Disseminated intravascular coagulation: a review.

Disseminated intravascular coagulation (DIC) results from activation of the blood coagulation cascade by various disease processes. DIC may occur with blunt head trauma and, with severe head trauma, may reflect brain parenchymal injury. Oral and maxillofacial surgeons who treat traumatized patients should be aware of the implications of DIC with regard to patient management, diagnosis, and surgical considerations.

Massive tongue necrosis secondary to temporal arteritis.

A case of unusually massive necrosis of the tongue secondary to temporal arteritis is presented. The clinician must include temporal arteritis in the differential diagnosis of patients presenting with signs and symptoms of tongue ischemia.

Diaphragm pacing in spinal muscular atrophy: case report.

A patient with a diagnosis of intermediate or benign spinal muscular atrophy was severely incapacitated from respiratory complications and alveolar hypoventilation and was confined to mechanical ventilatory support. After extensive diagnostic evaluation of her pulmonary status, including transcutaneous stimulation of the phrenic nerves associated with nasogastric and surface electrode recording of the diaphragmatic response, this patient had a phrenic neurostimulation system implanted bilaterally for diaphragm pacing. Although spinal muscular atrophy has not been previously recognized as an indication for diaphragm pacing, her subsequent social, physical, and psychological improvement indicate that it may be significantly beneficial in selected cases of alveolar hypoventilation due to spinal muscular atrophy or neuromuscular disease.