Animal models of eosinophilic esophagitis

Eosinophilic esophagitis is a chronic inflammatory disorder of the esophagus. Over the past 25 yr, great strides have been made toward understanding its pathogenesis, in part due to studies in several types of animal models. The vast majority of these models have been characterized in mice. In this review, we summarize the histopathological features of eosinophilic esophagitis recapitulated by these animal models, as well as discuss their strengths and weaknesses.

Basal cell carcinoma-clinico-pathological study in Eastern India in correlation with different risk factors

OBJECTIVES

To study the histological variants and mimickers of basal cell carcinoma (BCC) alongwith different risk factors among a group of patients from eastern India.

METHODS

The specimen for the study was sent by the dermatology department for histopathology after skin biopsy.

RESULTS

Out of 42 patients, 15 patients studied were males and the rest of the cases were females. The male to female ratio was 0.55:1. Maximum (15 cases) cases were in the age group of 50-59 years. Apart from sunlight, chronic arsenic exposure is an important risk factor of BCC. Basal cell hyperplasia and squamous cell carcinoma are the histological differential diagnosis of nodular BCC and basosquamous BCC.

CONCLUSION

BCC is a disease of the older age group and with female preponderance in our study. Nodular basal cell carcinoma was the most common histologic type of basal cell carcinoma. The face was the most common site for BCC followed by the scalp. UV radiations and Arsenic do play role in the pathogenesis of BCC. CD10 helps differentiate superficial BCC from basal cell hyperplasia.

Premalignant Changes in the Bronchial Epithelium Are Prognostic Factors of Distant Metastasis in Non-Small Cell Lung Cancer Patients

Background

The study assessed the possibility of dividing patients into groups based on the assessment of morphological changes in the epithelium of small-caliber bronchi located near the primary tumor in order to predict high and low risks of distant metastasis of non-small cell lung cancer.

Methods

In 171 patients with non-small cell lung cancer (T_1-4N_0-3M₀) in small-caliber bronchi taken at a distance of 3–5 cm from the tumor, various variants of morphological changes in the bronchial epithelium (basal cell hyperplasia (BCH), squamous cell metaplasia (SM), and dysplasia (D)) were assessed. Long-term results of treatment, namely, distant metastasis, were assessed after 2 and 5 years.

Results

During the follow-up period, distant metastases were found in 35.1% (60/171) of patients. Most often, they were observed in patients of the high-risk group: BCH+SM−D− (51.6%, 40/95) and BCH−SM+D+ (54.4%, 6/11). Less often, distant metastases were observed in low-risk group patients: BCH+SM+D− (6.7%, 3/45) and BCH−SM−D− (10.0%, 2/20). Tumor size, grade, and stage were significant predictors of metastasis only in the high-risk group. The 5-year metastasis-free survival was better in the low-risk group of distant metastases.

Conclusions

Isolated BCH or dysplasia in small bronchi distant from foci of tumor is associated with a high-risk distant metastasis and less 5-year metastasis-free survival.

Identification of anoctamin 1 (ANO1) as a key driver of esophageal epithelial proliferation in eosinophilic esophagitis

BACKGROUND

The pathology of eosinophilic esophagitis (EoE) is characterized by eosinophil-rich inflammation, basal zone hyperplasia (BZH), and dilated intercellular spaces, and the underlying processes that drive the pathologic manifestations of the disease remain largely unexplored.

OBJECTIVE

We sought to investigate the involvement of the calcium-activated chloride channel anoctamin 1 (ANO1) in esophageal proliferation and the histopathologic features of EoE.

METHODS

We examined mRNA and protein expression of ANO1 in esophageal biopsy samples from patients with EoE and in mice with EoE. We performed molecular and cellular analyses and ion transport assays on an in vitro esophageal epithelial 3-dimensional model system (EPC2-ALI) and murine models of EoE to define the relationship between expression and function of ANO1 and esophageal epithelial proliferation in patients with EoE.

RESULTS

We observed increased ANO1 expression in esophageal biopsy samples from patients with EoE and in mice with EoE. ANO1 was expressed within the esophageal basal zone, and expression correlated positively with disease severity (eosinophils/high-power field) and BZH. Using an in vitro esophageal epithelial 3-dimensional model system revealed that ANO1 undergoes chromatin modification and rapid upregulation of expression after IL-13 stimulation, that ANO1 is the primary apical IL-13-induced Cl- transport mechanism within the esophageal epithelium, and that loss of ANO1-dependent Cl- transport abrogated esophageal epithelial proliferation. Mechanistically, ANO1-dependent regulation of basal cell proliferation was associated with modulation of TP63 expression and phosphorylated cyclin-dependent kinase 2 levels.

CONCLUSIONS

These data identify a functional role for ANO1 in esophageal cell proliferation and BZH in patients with EoE and provide a rationale for pharmacologic intervention of ANO1 function in patients with EoE.

Molecular pathogenesis of human prostate basal cell hyperplasia

BACKGROUND

Understanding the molecular pathogenesis of distinct phenotypes in human benign prostatic hyperplasia (BPH) is essential to improving therapeutic intervention. Current therapies target smooth muscle and luminal epithelia for relief of lower urinary tract symptoms (LUTS) due to BPH, but basal cell hyperplasia (BCH) remains untargeted. The incidence of has been reported at 8-10%, but a molecular and cellular characterization has not been performed on this phenotype.

METHODS

Using freshly digested tissue from surgical specimens, we performed RNA-seq analysis of flow cytometry-purified basal epithelia from 3 patients with and 4 patients without a majority BCH phenotype. qPCR was performed on 28 genes identified as significant from 13 non-BCH and 7 BCH specimens to confirm transcriptomic analysis. IHC was performed on several non-BCH and BCH specimens for 3 proteins identified as significant by transcriptomic analysis.

RESULTS

A total of 141 human BPH specimens were analyzed for the presence of BCH. Clinical characteristics of non-BCH and BCH cohorts revealed no significant differences in age, PSA, prostate volume, medical treatment, or comorbidities. Quantitation of cellular subsets by flow cytometry in 11 BCH patients vs. 11 non-BCH patients demonstrated a significant increase in the ratio of basal to luminal epithelia in patients with BCH (P <0.05), but no significant differences in the total number of leukocytes. RNA-seq data from flow cytometry isolated basal epithelia from patients with and without BCH were subjected to gene set enrichment analysis of differentially expressed genes, which revealed increased expression of members of the epidermal differentiation complex. Transcriptomic data were complemented by immunohistochemistry for members of the epidermal differentiation complex, revealing a morphological similarity to other stratified squamous epithelial layers.

CONCLUSIONS

Increased expression of epidermal differentiation complex members and altered epithelial stratification resembles the progression of other metaplastic diseases. These data provide insight into the plasticity of the human prostate epithelium and suggest a classification of basal cell hyperplasia as a metaplasia.