Potentially targetable GAs in National Comprehensive Cancer Network NSCLC genes (30%) or intermediate or high TMB (43%, >10 mutations per Mb) were identified in most of the PSC cases. Thus, the use of comprehensive genomic profiling in clinical care may provide important treatment options for a historically poorly characterized and difficult to treat disease.

Reactive oxygen metabolites are potent inflammatory mediators that may be involved in tissue injury in inflammatory bowel disease. To evaluate their role in inflammatory bowel disease, we investigated the effects oflowering the activities of reactive oxygen metabolites in experimental colitis induced by intracolonic administration of acetic acid in rats. Intracolonic administration of5% acetic acid caused severe inflammation (mean (SEM) inflammatory score was 24*3 (0.7) of a maximum score of 32). Acetic acid at 2-5% produced moderate inflammation (score= 17 (1.4) v 4-0 (0.5) in control rats). This lower dose was used for subsequent experiments. Specific superoxide anion scavenger methoxypolyethylene glycol:superoxide dismutase, and reactive oxygen metabolites scavenger, sulfasalazine, significantly decreased the severity of inflammation (s'cores: 8 (4.4) and 9-8 (2.2) respectively). The xanthine oxidase inhibitors, tungsten and pterin aldehyde, failed to improve inflammation but another xanthine oxidase inhibitor, aliopurinol, a compound with known superoxide anion scavenging effect, did limit the inflammation (10(2)). Inhibition ofhydroxyl radicalproduction by deferoxamine orlowering hydroxyl radical values by a scavenger, dimethyl sulfoxide, did not affect the severity of inflammation. These data suggest: (1) that reactive oxygen metabolites play an important role in experimental colitis, (2) that the xanthine oxidase pathway is not a major source of reactive oxygen metabolites in colitis, and (3) that tissue injury in experimental colitis is not caused by generation of hydroxyl radicals.

Primary sarcomas of the great vessels are rare, but the most common site is the inferior vena cava. Herein are reported five new cases arising from the pulmonary veins with clinicopathologic correlation and comparison to previously reported cases. All new cases occurred in women ranging in age from 23 to 64 years at diagnosis (mean, 56 years). They had symptoms suggestive of left heart failure, including three patients with dyspnea, one with hemoptysis, and one with cough. Three cases showed tumor extension along the pulmonary veins into the left atrium. Tumors ranged in size from 2.8 to 7 cm in greatest dimension. Histologically, all were leiomyosarcomas. They were highly cellular tumors. Three cases had predominantly spindle cell morphology and two were predominantly epithelioid; one had foci of calcification. Most showed extensive necrosis. All tumors were reactive with antibodies to actin and desmin. Two cases were reactive with antibodies to MIC-2 (dotlike); two cases showed reactivity to keratin antibodies; and two showed reactivity for estrogen, progesterone receptor protein, or both. None were positive for antibodies to S-100 protein. All cases were treated with surgical excision. Follow-up ranged from 2 months to 21 years (mean, 4.8 years). Two patients were alive and well; two were alive with metastases; and one died of disease. Pulmonary vein sarcomas represent intermediate- to high-grade leiomyosarcoma. Although often lethal, complete surgical excision can lead to long-term survival. They occur predominantly in women and may express hormone receptors. Therefore, hormonal manipulation may offer promise as adjuvant therapy.

Inflammatory mediators may contribute to the diarrhea associated with colitis. Although the secretory action of such mediators is reported in normal tissue, there is little information regarding their effects on inflamed tissue. We examined the short-circuit current response (Isc) to these mediators, in mitomycin-C (MC)-induced colitis, a model with histological similarities to colitis in man. Rats were injected once with MC (3.25 mg/kg, intraperitoneally) or vehicle. The colons were removed three and seven days later and mounted, devoid of muscularis, in Ussing chambers for measurement of Isc, potential difference (PD), and resistance (Rt). MC-treated rats had diarrhea after three days, and microscopic studies revealed colonic inflammation. There were no significant differences in Rt, PD, and Isc between control and MC-treated tissues at three and seven days. Maximal increases in Isc to bradykinin, prostaglandin E1, carbachol, substance P, and serotonin were depressed at three and/or seven days after MC. The Isc response to theophylline was not affected. Theophylline activates secretion through an intracellular mechanism; the other agonists act by interaction with epithelial cell membranes. Therefore, the mechanism for the decreased Isc may result from uncoupling of receptors to second-messenger systems or desensitization of receptor-linked secretory mechanisms.

Reactive oxygen species (ROS) such as superoxide anion, hydrogen peroxide, hydroxyl radical, and hypochlorous acid have been implicated in the pathogenesis of inflammation and tissue injury in colitis. To determine whether or not anti-ROS agents can decrease the severity of colitis, we evaluated the effects of three known anti-ROS agents: catalase, WR-2721, and Cu(II)2(3,5-DIPS)4 on acetic acid-induced colonic inflammation in rats. Histologically, all three compounds significantly decreased the severity of colonic inflammation. The anti-ROS activity of these compounds was also tested using the luminol-enhanced chemiluminescence assay. Catalase, WR-2721, or Cu(II)2(3,5-DIPS)4 significantly inhibited luminol-enhanced chemiluminescence produced by inflamed colonic mucosa. These findings suggest that ROS, and in particular superoxide, hydrogen peroxide, and/or one of its secondarily derived species, may play an important role in acetic acid-induced colitis. Further studies are needed to determine the potential effectiveness of these compounds in human colitis.