The Transcription Factor MIST1 Is a Novel Human Gastric Chief Cell Marker Whose Expression Is Lost in Metaplasia, Dysplasia, and Carcinoma

Abstract

The lack of reliable molecular markers for normal differentiated epithelial cells limits understanding of human gastric carcinogenesis. Recognized precursor lesions for gastric adenocarcinoma are intestinal metaplasia and spasmolytic polypeptide expressing metaplasia (SPEM), defined here by ectopic CDX2 and TFF2 expression, respectively. In mice, expression of the bHLH transcription factor MIST1, normally restricted to mature chief cells, is down-regulated as chief cells undergo experimentally induced metaplasia. Here, we show MIST1 expression is also a specific marker of human chief cells. The mainstays of therapy in gastric carcinoma are early recognition, resection, and neoadjuvant or adjuvant therapy. However, gastric cancer remains the second largest cause of cancer-related mortality worldwide, 1 which drastically illustrates our lack of understanding of the sequence and progression of preneoplastic conditions. The traditional linear progression model of cellular changes, such as (Helicobacter-mediated) inflammation, atrophy, intestinal metaplasia (IM), dysplasia, and carcinoma, 2-4 does not apply to all cases and does not allow incorporation of more recently recognized entities. For example, there are distinct types of IMs, not all carrying definitive preneoplastic potential, and some authors have argued that IM in general is a paraneoplastic condition because the earliest gastric carcinomas arise from gasSupported by

The unfolded protein response is activated in Helicobacter-induced gastric carcinogenesis in a non-cell autonomous manner

“…This suggests that the UPR may have a mechanistic role in the transdifferentiation of mature chief cells into metaplasia as reported previously. 8,21 Lack of ER stress response during acute Helicobacter infection suggests activation of the UPR may be a reparative response of gastric epithelium to chronic Helicobacter infection. We hypothesize that in the Helicobacter-infected gastric mucosa, prolonged ER stress following chronic inflammation, compounded by aberrant mucin synthesis in the metaplastic cells triggers UPR activation.…”

“…Upregulation of HSPA5 was also seen in the inflammatory infiltrates in these patients although no abnormality in HSPA5 expression in chronic gastritis was observed, as also seen by qPCR ( Figure 1c). As recent studies have shown that transdifferentiation of chief cells contributes to gastric metaplasia in the human 21 and mouse, 8 we specifically examined HSPA5 expression in chief cells using MIST1 as a chief cell marker. In the normal human gastric mucosa, HSPA5 was expressed at a low level in the chief cell compartment at the bases of glands, correlating with MIST1 expression (Figure 2e).…”

Keratin 19 Epithelial Patterns in Cirrhotic Stroma Parallel Hepatocarcinogenesis

“…Immunohistochemistry (IHC) was performed automatically using a Benchmark XT automated slides stainer (Ventana Medical Systems, Inc., Tucson, AZ) using established protocols. 24 In brief, protocols consisted of pretreatment with CC1 (pH 8.0), incubation with primary antibodies, and detection using an IVIEW-DAB (diaminobenzidine) detection system (catalog No. 760-500; Ventana Medical Systems, Inc.) including ultraview inhibitor, horseradish peroxidase, multimer, chromogen, H 2 O 2 , and copper.…”

“…760-501; Ventana Medical Systems, Inc.) including enhancer, naphthol, red A, and fast red B. Immunofluorescence was performed manually according to established protocols. 24,25 In brief, sections were washed for 5 minutes (xylene ϫ3, 100% ethanol ϫ2, 95% ethanol ϫ1, 70% ethanol ϫ1, and PBS ϫ1), boiled in Trilogy for antigen retrieval (Cell Marque, Hot Springs, AR), rinsed in deionized water for 15 minutes, and washed with PBS. Sections were blocked in 1% bovine serum albumin and 0.3% Triton X-100 in PBS and were incubated using combinations of the primary antibodies.…”

“…Cells were defined via marker co-localized with nuclear staining in the same plane, whereas the outline of at least one cell formed a profile. Computer-assisted quantification algorithms were applied, 24 and segmentation of cells and profiles was achieved using threshold filters in combination with circularity and size cutoffs using "cell counter" and "analyze particle" plug-ins in ImageJ software (National Institutes of Health, Bethesda, MD). A customized link 24 between ImageJ, Photoshop CS3 (Adobe Systems, Inc., San Jose, CA), and ImageScope (Aperio Technologies, Inc.) was generated using AutoIT (version 3.2.12.0 by Jonathan Bennett), a freeware scripting language for automating the graphic user interface.…”