To determine whether DNA analysis can be performed using the supernatants of body fluids after centrifugation at 2,000 rpm for 10 minutes, peritoneal or pleural effusions or bile were examined for K-ras mutations in 34 cases of pancreatic, colorectal, gastric, esophageal, or hepatocellular carcinoma and 15 noncancer cases. The polymerase chain reaction products for K-ras gene codons 2 to 97 of exons 1 and 2 were generated with 41 (93%) of 44 body cavity fluid and 5 (100%) of 5 bile samples. By the single strand conformation polymorphism method, point mutations were detected in the ascites supernatants of 8 (89%) of 9 cases of pancreatic carcinoma. In the remaining case, no point mutation was demonstrated because few malignant cells were present in the ascites fluid. Furthermore, K-ras point mutations were observed in the ascites supernatants of 2 cases of colorectal carcinoma and 1 case of gastric carcinoma. The DNA analysis of the supernatant of ascites fluid showed a K-ras point mutation in 3 cases of false-negative cytologic diagnosis (2 cases of pancreatic carcinoma and 1 case of colorectal carcinoma). Direct sequencing confirmed identical point mutations in the supernatants, whole cell pellets, malignant cells from the cytologic smears of ascites fluid, and cancer tissues. This novel method allows simultaneous testing for genetic abnormalities in supernatants of body fluid, after removing cells for cytologic diagnosis.
Plasma ACTH and cortisol responses to intravenous injection of 100 micrograms synthetic ovine corticotropin-releasing factor (CRF) were studied in 4 patients with hypothalamic hypopituitarism, 2 patients with Sheehan's syndrome, 2 patients with isolated ACTH deficiency and 10 normal subjects. All 4 patients with hypothalamic hypopituitarism had exaggerated plasma ACTH responses to CRF compared to normal subjects and gradual but definite increases in plasma cortisol from low basal levels. Of 2 patients with Sheehan's syndrome, one had slight ACTH and cortisol increases after CRF injection, whereas the other had no increase in either. In 2 patients with isolated ACTH deficiency, plasma ACTH and cortisol remained undetectable (ACTH less than 10 pg/ml, cortisol less than 0.6 microgram/dl) after CRF injection. These results suggest that the CRF test is a useful tool in evaluating patients with secondary adrenocortical deficiency.
In order to clarify whether DNA analysis for K-ras mutation can be used to diagnose cancers in supernatants of pancreatic juice and bile, samples from 29 cases of pancreatic, biliary tract, gastric, and neuroendocrine carcinomas, 1 malignant lymphoma case, 2 cases of pancreatic adenoma, 9 cases of chronic pancreatitis and 21 other non-cancer cases were examined. Polymerase chain reaction (PCR) products for K-ras gene codons 2 to 97 of exons 1 and 2 were generated with 33/33 (100%) pancreatic juice and 41/41 (100%) bile samples. By the single strand conformation polymorphism (SSCP) method, point mutations were detected in the pancreatic juice or bile supernatants of 13/13 (100%) pancreas cancer cases, 5/14 (35.7%) biliary tract cancer cases, 1/2 (50.0%) pancreatic adenoma cases and 3/9 (33.3%) chronic pancreatitis cases. Direct sequencing confirmed identical point mutations in the supernatants, malignant cells of cytologic smears of pancreatic juice or bile and cancer tissues. The DNA analysis demonstrated the presence of K-ras point mutations in 3 cases of pancreatic carcinomas with false-negative cytologic diagnoses. This novel method allows simultaneous testing for genetic abnormalities in supernatants of pancreatic juice and bile, after removing cells for cytologic diagnosis and screening for pancreatic and biliary tract tumors.
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