Microglandular adenosis is an advanced precursor breast lesion with evidence of molecular progression to matrix-producing metaplastic carcinoma

ZNF862 induces cytostasis and apoptosis via the p21-RB1 and Bcl-xL-Caspase 3 signaling pathways in human gingival fibroblasts

OBJECTIVE

This study investigates the effects of ZNF862 on the proliferation and apoptosis of human gingival fibroblasts and their related mechanisms.

BACKGROUND

As a major transcription factor family, zinc finger proteins (ZFPs) regulate cell differentiation, growth, and apoptosis through their conserved zinc finger motifs, which allow high flexibility and specificity in gene regulation. In our previous study, ZNF862 mutation was associated with hereditary gingival fibromatosis. Nevertheless, little is known about the biological function of ZNF862. Therefore, this study was aimed to reveal intracellular localization of ZNF862, the influence of ZNF862 on the growth and apoptosis of human gingival fibroblasts (HGFs) and its potential related mechanisms.

METHODS

Immunohistochemistry, immunofluorescence staining, and western blotting were performed to determine the intracellular localization of ZNF862 in HGFs. HGFs were divided into three groups: ZNF862 overexpression group, ZNF862 interference group, and the empty vector control group. Then, the effects of ZNF862 on cell proliferation, migration, cell cycle, and apoptosis were evaluated. qRT-PCR and western blotting were performed to further explore the mechanism related to the proliferation and apoptosis of HGFs.

RESULTS

ZNF862 was found to be localized in the cytoplasm of HGFs. In vitro experiments revealed that ZNF862 overexpression inhibited HGFs proliferation and migration, induced cell cycle arrest at the G0/G1-phase and apoptosis. Whereas, ZNF862 knockdown promoted HGFs proliferation and migration, accelerated the transition from the G0/G1 phase into the S and G2/M phase and inhibited cell apoptosis. Mechanistically, the effects of ZNF862 on HGFs proliferation and apoptosis were noted to be dependent on inhibiting the cyclin-dependent kinase inhibitor 1A (p21)-retinoblastoma 1 (RB1) signaling pathway and enhancing the B-cell lymphoma-extra-large (Bcl-xL)-Caspase 3 signaling pathway.

CONCLUSION

Our results for the first time reveal that ZNF862 is localized in the cytoplasm of HGFs. ZNF862 can inhibit the proliferation of HGFs by inhibiting the p21-RB1 signaling pathway, and it also promotes the apoptosis of HGFs by enhancing the Bcl-xL-Caspase 3 signaling pathway.

Luminal-Type Invasive Carcinoma in Association With Microglandular Adenosis/Atypical Microglandular Adenosis: A Case Report and Molecular Comparison

Microglandular adenosis (MGA) is a proliferative breast lesion composed of small, uniform glands lacking a myoepithelial cell layer while still invested by the basement membrane. The glands percolate haphazardly through the breast parenchyma rather than maintaining a lobular architecture, typical of other forms of adenosis.MGA is a benign lesion though atypical forms have been well described, often in close association with carcinoma. MGA, atypical MGA (AMGA), and the vast majority of MGA-associated carcinomas (MGACA) are negative for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 (HER2) by immunohistochemistry. In light of these findings and early molecular studies, MGA is hypothesized to represent a clonal process and nonobligate precursor of basal-type breast carcinomas. We present the case of a 58-year-old woman and the first published molecular comparison of a luminal-type invasive ductal carcinoma with its associated MGA/AMGA. Analysis of small nucleotide variants (SNVs) revealed that 63% of the SNVs identified in the MGA were present in the AMGA while only 10% of them were present in the MGACA, suggesting a direct relationship between MGA and AMGA but not MGA and MGACA.

[Microglandular adenosis of the breast]

The presented case describes the difficulties of diagnosis of the breast microglandular adenosis (MGA), taken by clinicians for a malignant process due to the nature of growth and large size. Criteria for histological and immunohistochemical diagnosis and differentiation of MGA with malignant neoplasms, in particular, with tubular breast carcinoma, are presented. Taking into account the rarity of the pathology and the absence of described cases in the Russian-language literature, the observation is of interest to pathologists and clinicians.

Metaplastic Matrix-Producing Carcinoma and Apocrine Lobular Carcinoma In Situ Associated with Microglandular Adenosis: A Unique Case Report

Microglandular adenosis is a non-lobulocentric haphazard proliferation of small round glands composed of a single layer of flat to cuboidal epithelial cells. The glandular structures lack a myoepithelial layer; however, they are surrounded by a basement membrane. Its clinical course is benign, when it is not associated with invasive carcinoma. In around 30% of cases, there is a gradual transition to atypical microglandular adenosis, carcinoma in situ, and invasive breast carcinoma of several different histologic subtypes, including an invasive carcinoma of no special type, metaplastic matrix-producing carcinoma, secretory carcinoma, metaplastic carcinoma with squamous differentiation, acinic cell carcinoma, spindle cell carcinoma, and adenoid cystic carcinoma. Recent molecular studies suggest that microglandular adenosis is a non-obligate precursor of triple-negative breast carcinomas. In this manuscript, we present a unique case of microglandular adenosis associated with metaplastic matrix-producing carcinoma and HER-2 neu oncoprotein positive pleomorphic lobular carcinoma in situ with apocrine differentiation in a 79-year-old patient.

A novel gene ZNF862 causes hereditary gingival fibromatosis

Hereditary gingival fibromatosis (HGF) is the most common genetic form of gingival fibromatosis which is featured as a localized or generalized overgrowth of gingivae. Currently two genes (SOS1 and REST), as well as four loci (2p22.1, 2p23.3–p22.3, 5q13–q22, and 11p15), have been identified as associated with HGF in a dominant inheritance pattern. Here, we report 13 individuals with autosomal-dominant HGF from a four-generation Chinese family. Whole-exome sequencing followed by further genetic co-segregation analysis was performed for the family members across three generations. A novel heterozygous missense mutation (c.2812G > A) in zinc finger protein 862 gene (ZNF862) was identified, and it is absent among the population as per the Genome Aggregation Database. The functional study supports a biological role of ZNF862 for increasing the profibrotic factors particularly COL1A1 synthesis and hence resulting in HGF. Here, for the first time we identify the physiological role of ZNF862 for the association with the HGF.

Molecular analysis of encapsulated papillary carcinoma of the breast with and without invasion

Encapsulated papillary carcinomas (EPCs) of the breast are a unique variant of papillary carcinoma confined to a cystic space with absent or attenuated myoepithelial cell layer. Although staged as an in situ lesion, it can be associated with invasive ductal carcinoma (IDC). We sought to compare the genomic characteristics of pure EPC and EPC with associated invasive carcinoma (EPCi) at the genomic level. All cases of EPCi harbored recurrent hotspot mutations in PIK3CA. PIK3CA, KMT2A, and CREBBP deleterious somatic events were found across both tumor groups, irrespective of invasion status. At the whole transcriptomic level, EPCi cases displayed remarkably similar mRNA profiles when compared to EPC. When EPCi cases were compared with their corresponding IDC, despite significant overlap, we identified differential gene expression in 39 genes with enrichment of multiple pathways including extracellular matrix regulation, cell adhesion, and collagen fibril organization. Despite morphologic, genotypic, and transcriptomic overlap between pure EPC and EPCi, the latter tumors are likely advanced lesions with PIK3CA activating mutations and enrichment of stromal-related genes implicated in the switch to IDC.

Salivary gland-type mammary carcinoma arising in microglandular adenosis: A case report and clinicopathological review of the literature

INTRODUCTION

Microglandular adenosis (MGA) is a rare benign proliferative lesion lacking a myoepithelial cell layer; 27% of all reported cases have progressed to invasive carcinoma. Salivary gland-type carcinomas of the breast are also uncommon, representing 2% of all breast cancers. This wide spectrum of neoplasms tends to be triple negative and generally has an excellent prognosis. Given the rarity of salivary gland-type carcinomas of the breast arising from MGA, there are few reports of these cases in literature. As such, there is uncertainty regarding their diagnosis and treatment strategies.

PRESENTATION OF CASE

We report the rare case of a 66-year-old woman who presented with a triple negative, invasive carcinoma with salivary gland-type features, arising from MGA. The patient underwent mastectomy with sentinel lymph node biopsy, followed by Taxotere and Cyclophosphamide (TC) chemotherapy and 50 Gy in 25 fractions of radiation to her chest wall. We reviewed the available literature on salivary gland-type breast carcinomas arising from MGA.

DISCUSSION

Despite the generally unfavourable characteristics associated with carcinoma arising in microglandular adenosis (MGACA), most patients with MGACA have favourable outcomes.

CONCLUSIONS

The findings of the present case and reviewed cases are consistent with the literature on MGA, atypical MGA (AMGA), and MGACA. Future study of this rare entity is warranted to establish a consensus surrounding its clinical significance and treatment methods.

Matrix-producing Breast Carcinoma: A Rare Subtype of Metaplastic Breast Carcinoma

Matrix-producing carcinoma (MPC) is a rare subtype of metaplastic breast carcinoma (MBC) that was first described in 1989 by Wargotz and Norris. It accounts for less than 1% of breast carcinomas and has distinctive clinical, morphological, and immunohistochemical features. Histologically it consists of invasive carcinoma of no special type with transition to cartilaginous or osseous matrix without a spindle cell component. Data on this entity are limited with the literature consisting mostly of case reports and a small number of case series. We report a case of matrix-producing breast carcinoma, with excellent clinical outcome. We also discuss the histogenesis, imaging, histological, and immunohistochemical characteristics, treatment, and focus on the differential diagnosis of this rare tumor.

Microglandular Adenosis and Associated Invasive Carcinoma

CONTEXT.—

Microglandular adenosis is a rare borderline neoplastic lesion of the breast composed of haphazardly located small, round tubules with a single cell layer interspersed within breast stroma and/or adipose tissue. Microglandular adenosis is devoid of a myoepithelial cell layer, and has a characteristic immunophenotype, being positive for S100 and negative for estrogen receptor, progesterone receptor, and HER2/neu. When associated with cancer, microglandular adenosis and associated invasive carcinoma share the same molecular alterations, including TP53 mutation; therefore, microglandular adenosis is considered a nonobligate precursor of triple (HER2/neu, estrogen and progesterone receptors)-negative breast carcinoma. Microglandular adenosis is an important diagnostic pitfall as it can be easily mistaken for a low-grade invasive carcinoma.

OBJECTIVE.—

To provide a review of the clinicopathologic features of microglandular adenosis and associated invasive carcinoma, with emphasis on key features separating entities in the differential diagnosis.

DATA SOURCES.—

Review of current literature on microglandular adenosis and associated invasive carcinoma and personal experience of authors.

CONCLUSIONS.—

Microglandular adenosis can mimic breast carcinoma; attention to key features, including morphologic-immunophenotypic correlation, is essential in establishing the diagnosis.