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1.
Lessons Learned
  • Afatinib and selumetinib can be combined in continuous and intermittent dosing schedules, albeit at lower doses than approved for monotherapy.
  • Maximum tolerated dose for continuous and intermittent schedules is afatinib 20 mg once daily and selumetinib 25 mg b.i.d.
  • Because the anticancer activity was limited, further development of this combination is not recommended until better biomarkers for response and resistance are defined.
BackgroundAntitumor effects of MEK inhibitors are limited in KRAS‐mutated tumors because of feedback activation of upstream epidermal growth factor receptors, which reactivates the MAPK and the phosphoinositide 3‐kinase–AKT pathway. Therefore, this phase I trial was initiated with the pan‐HER inhibitor afatinib plus the MEK inhibitor selumetinib in patients with KRAS mutant, PIK3CA wild‐type tumors.MethodsAfatinib and selumetinib were administered according to a 3+3 design in continuous and intermittent schedules. The primary objective was safety, and the secondary objective was clinical efficacy.ResultsTwenty‐six patients were enrolled with colorectal cancer (n = 19), non‐small cell lung cancer (NSCLC) (n = 6), and pancreatic cancer (n = 1). Dose‐limiting toxicities occurred in six patients, including grade 3 diarrhea, dehydration, decreased appetite, nausea, vomiting, and mucositis. The recommended phase II dose (RP2D) was 20 mg afatinib once daily (QD) and 25 mg selumetinib b.i.d. (21 days on/7 days off) for continuous afatinib dosing and for intermittent dosing with both drugs 5 days on/2 days off. Efficacy was limited with disease stabilization for 221 days in a patient with NSCLC as best response.ConclusionAfatinib and selumetinib can be combined in continuous and intermittent schedules in patients with KRAS mutant tumors. Although target engagement was observed, the clinical efficacy was limited.  相似文献   
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BACKGROUNDAdrenal incidentaloma (AI) has been frequently encountered in the clinical setting. It has been shown that primary aldosteronism (PA) or subclinical Cushing’s syndrome (SCS) are the representative causative diseases of AI. However, the coexistence of PA and SCS has been reportedly observed. Recently, we encountered a case of AI, in which PA and SCS coexisted, confirmed by histopathological examinations after a laparoscopic adrenalectomy. We believe that there were some clinical implications in the diagnosis of the present case.CASE SUMMARYA 58-year-old man presented with lower right abdominal pain with a blood pressure of 170/100 mmHg. A subsequent computed tomography scan revealed right ureterolithiasis, which was the cause of right abdominal pain, and right AI measuring 22 mm × 25 mm. After the disappearance of right abdominal pain, subsequent endocrinological examinations were performed. Aldosterone-related evaluations, including adrenal venous sampling, revealed the presence of bilateral PA. In addition, several cortisol-related evaluations showed the presence of SCS on the right adrenal adenoma. A laparoscopic right adrenalectomy was then performed. The histopathological examination of the resected right adrenal revealed the presence of a cortisol-producing adenoma, while CYP11B2 immunoreactivity was absent in this adenoma. However, in the adjacent non-neoplastic adrenal, multiple CYP11B2-positive adrenocortical micronodules were detected, showing the presence of aldosterone-producing adrenocortical micronodules. CONCLUSIONCareful clinical and pathological examination should be performed when a patient harboring AI presents with concomitant SCS and PA.  相似文献   
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Objective: Hesperidin, an abundant flavonoid in citrus fruit, and its aglycone, hesperetin, have been reported to possess various physiological activities, including antioxidant, anti-inflammatory, hypolipidemic, and antihypertensive activities. In this study, we investigated whether α-glucosyl hesperidin and water-dispersible hesperetin have protective effects on atherosclerotic progression in apolipoprotein E knockout (Apo-E KO) mice.

Methods: Ten-week-old male Apo-E KO mice were randomly assigned a regular high-fat diet, a high-fat diet with 0.5% α-glucosyl hesperidin, or a high-fat diet with 0.1% water-dispersible hesperetin for 12?weeks. Measurement of plasma total cholesterol levels, histological staining of aortic root, and immunohistochemistry for macrophages were performed to evaluate atherosclerotic plaque formation. Vascular reactivity of mouse aortic rings was also measured.

Results: Both α-glucosyl hesperidin and water-dispersible hesperetin reduced plasma total cholesterol level. They also reduced plaque formation area, adipose deposition, and macrophage infiltration into atherosclerotic lesion. Vascular-endothelium-dependent relaxation in response to acetylcholine was improved in both experimental diet groups compared to the high-fat diet group.

Conclusions: Our study suggests that both α-glucosyl hesperidin and water-dispersible hesperetin exert protective effects on atherosclerotic progression in Apo-E KO mice because they exhibit hypolipidemic activity, reduce inflammation through macrophages, and prevent endothelial dysfunction.  相似文献   

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Although recent studies revealed that adipose tissue accelerates pancreatic tumor progression with excessive extracellular matrix, key players for desmoplasia in the adipose microenvironment remains unknown. Here, we investigated the roles of adipose tissue-derived stromal cells (ASCs) in desmoplastic lesions and tumor progression by in vitro and in vivo experiments. In a three-dimensional (3-D) organotypic fat invasion model using visceral fat from CAG-EGFP mice, GFP-positive fibroblastic cells infiltrated toward cancer cells. When tumor cells were inoculated into transplanted visceral fat pads in vivo, tumor weights and stromal components were enhanced compared to subcutaneous and orthotopic tumor cells inoculated without fat pads. Expression of αSMA in established human ASCs was lower compared to cancer associated fibroblasts, and the 3-D collagen matrices produced by ASCs cultured in cancer cell-conditioned medium changed from loose to dense structures that affected the motility of cancer cells. Microarray analyses revealed upregulation of S100A4 in ASCs, while S100A4-positive stromal cells were observed at extrapancreatic invasion sites of human pancreatic cancer. The present findings indicate that ASCs are recruited to extrapancreatic invasion sites and produce dense collagen matrices that lead to enhanced tumor progression. Both inhibition of ASCs recruitment and activation could lead to a novel antistromal therapy.  相似文献   
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Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis.  相似文献   
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