Preoperative cetuximab and radiation (XRT) for patients (pts) with surgically resectable esophageal and gastroesophageal junction (GEJ) carcinomas: A pilot study from the Hoosier Oncology Group and the University of Texas Southwestern

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Background: Pre-operative chemoradiotherapy (CRT) followed by surgical resection is a standard treatment option for pts with resectable esophageal or GE junction (GEJ) carcinomas (CA). Cetuximab, when combined with XRT is effective treatment for locally advanced cancers of the head and neck. We conducted this study to evaluate this regimen in pts with esophageal and GEJ CA. Methods: This is a single arm, open label pilot study combining cetuximab with XRT for pts with resectable esophageal and GEJ CA. The primary objective is to determine the pathologic complete response rate (pCR) (null hypothesis: p=0.20; alternative hypothesis: p=0.35) and determine the feasibility and toxicity of this regimen when given prior to esophagectomy. Key eligibility criteria are: squamous cell (SC)or adenoCA of the esophagus or GEJ, ECOG PS 0–2, clinical stage II -IVa, and eligible for esophagectomy. Pts received a loading dose of cetuximab at 400mg/m2 2 weeks prior to XRT, then weekly at 250 mg/m2 starting one week prior to XRT until completion of 50.4 Gy XRT. After satisfactory recovery, pts had esophagectomy. Results: Patient characteristics (n=40): median age 65 years (range, 54–82); 92% male; PS 0/1 63%/32%; esophageal/GEJ 65%/35%; adenoCA/SC 78%/22%; 36 pts have completed cetuximab and radiation and 26 pts have undergone esophagectomy. Of the 26 pts that have undergone esophagectomy, 13 obtained a pCR. 5/13 SC had pCR and 8/13 adenoCA had pCR. 10 pts did not undergo surgery for various reasons including disease progression (n=7), AE unrelated to treatment (n=2), and personal decision to forgo esophagectomy (n=1). 4 patients are still completing cetuximab/XRT. The most common G3 adverse event was rash (56%). Other G3 toxicities were infrequent and included dysphagia (6%), infection (6%), and GI bleed (3%). There have been no treatment or surgery related deaths. Conclusions: Cetuximab and XRT results in pCR's in pts with esophageal and GEJ CA (rate of pCR 13/36), including patients with either SC or adenoCA histologies. G3/4 toxicities, including dysphagia were generally uncommon. Further study of this combination prior to esophagectomy is warranted.

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Gene Expression Profiling during Erythroid Differentiation of K562 Cells

We studied the temporal changes in gene expression in K562 cells at intervals from 2 to 48 h following induction using differential display polymerase chain reaction and gene expression arrays. More than 110 cDNA fragments representing 86 unique mRNAs were either up- or downregulated during erythroid differentiation. Sixty-one of the differentially expressed cDNA fragments had more than 95% homology to known GenBank sequences; 21 represented cDNA sequences with only dbEST or high-throughput gene-screening database matches. Four fragments had no database matches. Using gene expression arrays, 73 differentially expressed genes were observed. Unique expressed sequence tags (ESTs) were used to "clone" two novel genes from available databases and their tissue expression was examined. Erythroid maturation in induced K562 cells is associated with differential expression of many genes. Some differentially expressed clones were transcription factors and 25 expressed fragments with open reading frames were found whose function remains unknown.