Hyeyoon Chang

EGF induces epithelial-mesenchymal transition through phospho-Smad2/3-Snail signaling pathway in breast cancer cells

Epithelial-mesenchymal transition (EMT) can contribute to tumor invasion, metastasis, and resistance to chemotherapy or hormone therapy. EMT may be induced by a variety of growth factors, such as epidermal growth factor (EGF). Most studies regarding EMT have focused on TGF-β-Smads signaling. The mechanism of EGF-induced EMT via activation of the Smad2/3 in breast cancer cells, MCF-7 and MDA-MB-231, remains unclear. The expression levels of Snail, vimentin, and fibronectin were increased by EGF treatment in a time-dependent manner, while the expression level of E-cadherin was decreased. EGF-induced nuclear co-localization of phospho-Smad2/3 and Snail and cancer cell migration were inhibited by pretreatment with an ERK1/2 inhibitor, PD98059 and a phospho-Smad2 inhibitor, SB203580. Knockdown of Smad2/3 expression suppressed EGF-induced expressions of Snail, vimentin, fibronectin, and cancer cell invasion, suggesting an acquisition of the mesenchymal and migratory phenotype in less aggressive MCF-7 cells. Moreover, MDA-MB-231 cells were shown that EGF-induced EMT, and cell invasion through ERK1/2-phospho-Smad2/3-Snail signaling pathway. We have discovered that EGF-stimulated activation of Smad2/3 upregulated several key EMT markers, inhibited E-cadherin expression, promoted EMT, enhanced migration and invasion in MCF-7 and MDA-MB-231 breast cancer cells. Identification of this molecular mechanism may provide new molecular targets for the development of therapies for metastatic breast cancer.

Comparison of diagnostic values of thyroid aspiration samples using liquid‐based preparation and conventional smear: one‐year experience in a single institution

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Fine‐needle aspiration (FNA) is the most useful tool in the diagnosis of thyroid nodules. Liquid‐based preparation (LBP) in FNA of thyroid nodules is now widely used and is replacing the conventional smear (CS). We compared the diagnostic value of the LBP method with that of CS in thyroid lesions. A total of 1767 CS FNA samples and 2523 LBP FNA samples were included in this comparison of diagnostic values. We also assessed the differences in cytomorphologic features in 41 randomly selected cases of PTC. The measured sensitivities of CS and LBP were 78.9% and 76.3%, respectively, and the specificities were 64.2% and 54.9%, respectively, whereas the positive predictive values were 92.3% and 94.3%, respectively, and the negative predictive values were 89.5% and 81.8%, respectively. The cytomorphological features of LBP showed better‐preserved nuclear details, cleaner background and fewer large papillae than were evident in CS. The results indicate that LBP reduces the diagnosis of non‐diagnostic or unsatisfactory/atypia of undetermined significance or follicular lesion of undetermined significance, although the diagnostic values for CS and LBP are not appreciably different.

Programmed death-ligand 1 expression in gastric adenocarcinoma is a poor prognostic factor in a high CD8+ tumor infiltrating lymphocytes group

Gastric adenocarcinoma is one of the most common causes of cancer-related death. In this study, we conducted immunohistochemical studies for PD-L1, PD-1, CTLA-4, and CD8 using tissue microarrays from 464 gastric cancer samples and evaluated the correlations between their expression, clinicopathologic factors, and five-year overall survival. PD-L1 and PD-1 expression was significantly correlated with several adverse prognostic pathologic factors, including higher T-stage, diffuse Lauren histologic type, and lymphatic invasion. Conversely, CTLA-4 expression was correlated with factors of favorable clinical outcomes. A complete case analysis revealed that high PD-L1 and PD-1 expression had an adverse effect on five-year overall survival in univariate analyses. Subgroup analyses wherein patients were divided into two groups according to CD8+ tumor infiltrating lymphocyte levels (high and low) showed that high PD-L1 expression was a significant adverse prognostic factor only in the high CD8+ tumor-infiltrating lymphocytes group. Further research and clinical trials are needed to determine the clinical usefulness of these findings.

Sclerosing Polycystic Adenosis of the Nasal Septum: The Risk of Misdiagnosis

Sclerosing polycyctic adenosis (SPA) is a rare lesion of unknown etiology morphologically resembling fibrocystic changes of the breast. To date, approximately 41 cases of SPA have been reported. Most cases of SPA have originated in the parotid and submandibular glands, with a few cases of intra-oral minor salivary gland origin. This is the first reported case of sclerosing polycystic adenosis of nasal minor salivary gland origin. The differential diagnosis of SPA includes polycystic disease, sclerosing sialadenitis, and benign and malignant glandular neoplasias. Although atypia ranging from mild dysplasia to carcinoma in situ can occur in some cases, SPA has a favorable outcome. It is important to be familiar with SPA to avoid aggresive treatment that results from a misdiagnosis. We present a case of a 49-year-old man who had 1-year history of right nasal obstruction.

Expression of ROR1, pAkt, and pCREB in gastric adenocarcinoma

The receptor tyrosine kinase-like orphan receptor 1 (ROR1) is a transmembrane protein of receptor tyrosine kinase family. High expression of ROR1 is reported in many types of malignancies and is thought to be involved in tumor growth, apoptosis, and epithelial-mesenchymal transition. In this study, we examined the expression of ROR1, pAkt, and pCREB in gastric adenocarcinoma and analyzed with clinicopathologic factors and tumor proliferation. Tissue microarray blocks containing 424 gastric adenocarcinomas were used for immunohistochemical staining. Ki-67 labeling index was used for tumor proliferation activity. High expression of ROR1 (63%), pAkt (36%), and pCREB (20%) was observed in gastric adenocarcinomas, and expression of these proteins was well intercorrelated. ROR1 and pCREB expression was associated with Ki-67 labeling index (P < .001). Expression of pAkt and pCREB group showed longer survival in univariate analysis (P = .007 and P < .001, respectively). This is the first study that analyzed ROR1 expression in gastric adenocarcinoma tissue samples. We revealed that gastric adenocarcinomas highly express ROR1 and related proteins and its prognostic significance. ROR1 in gastric adenocarcinoma could be possible candidate of therapeutic target, and more comprehensive study is required.

Pigmented Perivascular Epithelioid Cell Tumor (PEComa) of the Kidney: A Case Report and Review of the Literature

Heavily pigmented perivascular epithelioid cell tumors (PEComa) are rare, only eight cases of which have been reported. Unlike typical epithelioid angiomyolipoma, most of these tumors have been encountered in female patients without tuberous sclerosis. The long-term prognosis thereof is undetermined. Cytological similarity and heavy melanin pigment make it difficult for pigmented PEComa to be differentiated from pigmented clear cell renal cell carcinoma or malignant melanoma. The immunoprofile of tumor cells, such as human melanoma black-45 expression, as well as the absence or presence of other melanocytic or epithelial markers, are helpful in determining a differential diagnosis. Here we report a case of heavily pigmented PEComa of the right kidney and review the literature describing this tumor. In this case, the immunoprofile and clinical features corresponded well to those described in the literature. Since the prognosis of such disease has not yet been established, close follow-up of this patient was recommended.

Effectiveness of Silver-enhanced In Situ Hybridization for Evaluating HER2 Gene Status in Invasive Breast Carcinoma: A Comparative Study

BACKGROUND AND AIMS HER2 gene amplification occurs in breast cancers and has implications for treatment and prognosis. Recently, a new direct evaluation technique, silver enhanced in situ hybridization (SISH) was developed for evaluating HER2 gene status. This study was performed to evaluate the SISH technique for clinical use by comparing it to that of fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). METHODS We studied 543 cases of excised breast specimens diagnosed as invasive ductal carcinoma by IHC, FISH, and SISH using a tissue microarray. IHC, FISH, and SISH results were interpreted according to the American Society of Clinical Oncology/College of American Pathologists guidelines. A total of seven English studies that reported the concordance rates of SISH and BDISH compared to FISH published before July 2011 were retrieved. RESULTS The consensus concordance rate between SISH and FISH was 96.69% (kappa value = 0.9175). The pooled sensitivity was 0.94 [95% confidence interval (CI) = 0.91-0.97], and the pooled specificity was 0.98 (95% CI = 0.96-099) in a meta-analysis of the retrieved studies and this study. Area under the receiver operating characteristics curve was 0.9906. CONCLUSIONS SISH technique is an effective modality and is comparable with FISH for evaluating HER2 gene amplification in patients with breast carcinoma.

Overexpression of PD-L2 is associated with shorter relapse-free survival in patients with malignant salivary gland tumors

Objectives PD-1/PD-L1 and CTLA-4 have been investigated and are thought to play an important role in tumor evasion. This study aimed to investigate expression patterns of immune-related molecules, and their clinical impacts in malignant salivary gland tumors. Patients and methods We performed immunohistochemical staining for PD-L1, PD-L2, CTLA-4, PD-1, and CD8+ tumor-infiltrating lymphocytes in 70 malignant salivary gland tumors. Protein expression was assessed by H-score by multiplying the staining intensity by the percentage of cells with positive staining. Results The tumors comprised mucoepidermoid carcinomas (38.6%), adenoid cystic carcinomas (21.4%), salivary duct carcinomas (15.7%), and others. In malignant salivary gland tumors, PD-L2 expression was high, while expression of PD-L1 was relatively low in terms of the percentage of positively stained cells and the staining intensity. In univariate analysis, PD-L2 expression (H-score <1 vs ≥1), PD-1 (H-score <1 vs ≥1), and CD8+ tumor-infiltrating lymphocytes (H-score <1 vs ≥1) were significant prognostic factors. In multivariate analysis, low PD-L2 expression (H-score <1) was independently associated with shorter relapse-free survival (hazard ratio =6.514; 95% confidence interval, 1.2–36.2; P=0.032). Conclusion In summary, PD-L2 is potentially an important biomarker in malignant salivary gland tumors, especially in regard to relapse.

SIRT7, H3K18ac, and ELK4 Immunohistochemical Expression in Hepatocellular Carcinoma.

Background SIRT7 is one of the histone deacetylases and is NAD-dependent. It forms a complex with ETS-like transcription factor 4 (ELK4), which deacetylates H3K18ac and works as a transcriptional suppressor. Overexpression of SIRT7 and deacetylation of H3K18ac have been shown to be associated with aggressive clinical behavior in some cancers, including hepatocellular carcinoma (HCC). The present study investigated the immunohistochemical expression of SIRT7, H3K18ac, and ELK4 in hepatocellular carcinoma. Methods A total of 278 HCC patients were enrolled in this study. Tissue microarray blocks were made from existing paraffin-embedded blocks. Immunohistochemical expressions of SIRT7, H3K18ac and ELK4 were scored and analyzed. Results High SIRT7 (p = .034), high H3K18ac (p = .001), and low ELK4 (p = .021) groups were associated with poor outcomes. Age < 65 years (p = .028), tumor size ≥ 5 cm (p = .001), presence of vascular emboli (p = .003), involvement of surgical margin (p = .001), and high American Joint Committee on Cancer stage (III&V) (p < .001) were correlated with worse prognoses. In multivariate analysis, H3K18ac (p = .001) and ELK4 (p = .015) were the significant independent prognostic factors. Conclusions High SIRT7 expression with poor overall survival implies that deacetylation of H3K18ac contributes to progression of HCC. High H3K18ac expression with poor prognosis is predicted due to a compensation mechanism. In addition, high ELK4 expression with good prognosis suggests another role of ELK4 as a tumor suppressor beyond SIRT7’s helper. In conclusion, we could assume that the H3K18ac deacetylation pathway is influenced by many other factors.

Detection of human papillomavirus in Korean breast cancer patients by real-time polymerase chain reaction and meta-analysis of human papillomavirus and breast cancer

Background Human papillomavirus (HPV) is a well-established oncogenic virus of cervical, anogenital, and oropharyngeal cancer. Various subtypes of HPV have been detected in 0% to 60% of breast cancers. The roles of HPV in the carcinogenesis of breast cancer remain controversial. This study was performed to determine the prevalence of HPV-positive breast cancer in Korean patients and to evaluate the possibility of carcinogenic effect of HPV on breast. Methods Meta-analysis was performed in 22 case-control studies for HPV infection in breast cancer. A total of 123 breast cancers, nine intraductal papillomas and 13 nipple tissues of patients with proven cervical HPV infection were tested by real-time polymerase chain reaction to detect 28 subtypes of HPV. Breast cancers were composed of 106 formalin-fixed and paraffin embedded (FFPE) breast cancer samples and 17 touch imprint cytology samples of breast cancers. Results The overall odds ratio between breast cancer and HPV infection was 5.43 (95% confidence interval, 3.24 to 9.12) with I2 = 34.5% in meta-analysis of published studies with case-control setting and it was statistically significant. HPV was detected in 22 cases of breast cancers (17.9%) and two cases of intaductal papillomas (22.2%). However, these cases had weak positivity. Conclusions These results failed to serve as significant evidence to support the relationship between HPV and breast cancer. Further study with larger epidemiologic population is merited to determine the relationship between HPV and breast cancer.