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K Sorenson

Publications and source records attributed to K Sorenson.

9 recordsLinked to original sources

Interferon regulatory factor expression in human breast cancer.

OBJECTIVE: To investigate the expression of interferon regulatory factors 1 and 2 (IRF-1 and IRF-2) in human breast cancer. SUMMARY BACKGROUND DATA: Interferon regulatory factors 1 and 2 are transcription factors in the interferon gamma signal transduction pathway. IRF-1 acts as the effector arm of the interferon gamma response; IRF-2 binds to the same DNA consensus sequence and opposes IRF-1 activity. Previous work in the authors' laboratory has shown the tumor suppressor activity of IRF-1 expression and the oncogenic effect of IRF-2 in human and murine tumor models, including human breast cancer cell lines. The authors' hypothesis is that this pathway is involved in human tumor development, and alterations in the expression of IRF-1 and IRF-2 may occur in breast cancer tissue compared with normal breast tissue, and between more and less differentiated breast cancers. METHODS: Formalin-fixed paraffin-embedded human archival tissue specimens were obtained from 33 patients with pure ductal carcinoma in situ (DCIS) and 49 women with invasive ductal cancer. Adjacent areas of normal breast tissue were assayed in 31 women. These specimens were stained with polyclonal IRF-1 and IRF-2 antibodies using an avidin-biotin-peroxidase complex technique after epitope retrieval. RESULTS: Most normal breast tissue showed expression of IRF-1 and no expression of IRF-2 by immunohistochemistry. High-grade DCIS or node-positive invasive ductal cancers were less likely to express the tumor suppressor IRF-1 than normal tissue. More strikingly, high-grade DCIS and invasive ductal cancers were much more likely to express the oncogenic IRF-2 protein than was normal tissue. CONCLUSIONS: Expression of IRF-1 and IRF-2 is altered in human breast cancer compared with normal adjacent tissue. The loss of IRF-1 expression is consistent with tumor suppressor loss and the development of IRF-2 expression with oncogenic activation. These data support the hypothesis that this pathway is involved in human breast oncogenesis, which warrants further investigation regarding prognostic and therapeutic implications.

Breast Neoplasms↗

Small cell carcinoma of the genitourinary tract: an immunohistochemical, electron microscopic and clinicopathological study.

We examined 13 cases of small cell carcinoma of the genitourinary tract to evaluate and compare the immunocytochemical and ultrastructural features as well as the clinicopathological behavior. Immunohistochemical stains revealed that neuron specific enolase and chromogranin showed differences in staining between the bladder and prostate, as well as between the small cell and adenocarcinomatous components of the prostate. Also, synaptophysin was negative over-all in 12 of 13 cases. Epithelial membrane antigen, carcinoembryonic antigen and keratin showed strong focal positivity within the small cell component. Electron microscopy was performed in 4 cases, with 3 demonstrating neurosecretory granules. Clinically, 6 of the 7 patients with adenocarcinoma/small cell carcinoma of the prostate did poorly, all with a survival of 15 months or less. Of 5 patients with transitional cell/small cell carcinoma of the bladder 2 fared better (both had no evidence of disease at 12 months and 11 years, respectively). Based upon the immunostaining and electron microscopic findings, small cell carcinoma of the genitourinary tract is heterogeneous in appearance and, therefore, may arise from a multipotential cell of origin. This cell of origin may be organ-specific, as demonstrated by the variability in staining characteristics among the prostate, bladder and kidney, as well as by the differences in the clinical behavior of these malignancies. Small cell carcinoma of the prostate has a poor prognosis, while small cell carcinoma of the bladder may portend a better prognosis if diagnosed at an early stage.

Adenocarcinoma↗

Computed tomography-guided retroperitoneal biopsies.

A retrospective review was performed on consecutive patients who had a computed tomographic (CT) biopsy of the retroperitoneum at University Hospitals of Cleveland. Biopsies were performed using a 20-gauge Chiba needle (University Medical Instruments Corp, Ballston Spa, NY) and a 14-gauge Tru-Cut needle (Baxter Pharmaseal, Valencia, CA). The results included success rate, failure, and complications, and were determined by a review of patient charts, surgical results, and autopsy results. The 20-gauge needle aspirations were accurate in suggesting the diagnosis in 20 of 22 cases of metastatic disease and ten of 15 cases of lymphoma. Using the 20-gauge needle, it was not possible to make a specific diagnosis in any of the lymphoma patients or for unusual benign disorders. With the 14-gauge Tru-Cut needle, the correct diagnosis was made in 13 of 13 cases of metastatic disease, ten of 11 cases of lymphoma, and two of 2 cases of unusual benign disorders. It was also possible to make the specific diagnosis of the lymphoma type in ten of 11 cases. The only complication was a small subcutaneous hematoma following a biopsy with a 20-gauge Chiba needle.

Biopsy, Needle↗

Predisposition to urinary tract epithelial metaplasia in Schistosoma haematobium infection.

Although there is strong epidemiologic evidence linking Schistosoma haematobium infection with carcinoma of the bladder, the utility of cytologic screening for urinary tract cancer has not been critically evaluated in S. haematobium-endemic populations. The present cross-sectional study examined urine cytology findings among 1,014 residents (ages 1 to 91) of the S. haematobium-endemic Msambweni area of Coast Province, Kenya. Among 705 evaluable cytology specimens, prevalence of inflammation (39%), hyperkeratosis (30%), metaplasia (33%), and frank atypia (0.4%) was notably higher than in previously studied, non-endemic populations. Overall, S. haematobium infection was strongly associated with increased risk for cytologic abnormality (> 2.8-fold relative risk of metaplasia or hyperkeratosis; P < 0.001). Age-group analysis confirmed parallel increases in metaplasia and S. haematobium infection prevalence early in life (from age I to 15 for both boys and girls). However, above age 20, metaplasia prevalence persisted at 33-45% prevalence despite a decline in infection prevalence and intensity. Prevalence of advanced (moderate or severe) metaplasia showed two age-related peaks: the first at 10-14 years of age (at the time of peak infection), and the second among subjects > or = 60 years old. No cancers were detected in the study population either on cytology or on follow-up ultrasound examination. These data suggest an age-dependent progression of cellular abnormalities in the urinary epithelium that is associated with chronic S. haematobium infection, which becomes independent of concurrent infection intensity as subjects grow older. Implications for cancer screening are discussed.

Adolescent↗