Aberrant keratin 7 and 20 expression in triple-negative carcinoma of the breast

Keratin 7 expression in different anatomical parts of colonic epithelium in inflammatory bowel diseases and its prognostic value: a 3-year follow-up study

The diagnosis of inflammatory bowel diseases (IBD) may be challenging and their clinical course, characterized by relapses and spontaneous or drug-induced remissions, is difficult to predict. Novel prognostic biomarkers are needed. Keratin 7 (K7) is a cytoskeletal intermediate filament protein which is not normally expressed in the colonic epithelium. It was recently shown that K7 expression in the colonic epithelium is associated with ulcerative colitis and Crohn's disease, the two main subtypes of IBD. Here we investigated IBD associated K7 neo-expression in different regions of colon and terminal ileum. The correlation of the K7 expression with the inflammatory activity of the epithelium was analyzed in each region. The prognostic value of K7 was estimated by comparing the clinical disease activity after 3 years with the K7 expression at the time of enrollment. Our data shows that the level of K7 expression in inflamed epithelium varies depending on the anatomical region and it is the most pronounced in ascending and descending colon, but it did not predict the severity of IBD for the following 3 years. These results warrant future studies focusing on the biological role of K7 in colon and its utilization as potential IBD biomarker.

Cytokeratin 7 and cytokeratin 20 expression in cancer: A tissue microarray study on 15,424 cancers

Combined analysis of cytokeratin 7 (CK7) and cytokeratin 20 (CK20) is often used for assessing the origin of metastatic cancer. To evaluate the diagnostic utility of CK7 and CK20, tissue microarrays containing 15,424 samples from 120 different tumor types and subtypes and 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. CK7 positivity was seen in 52% (8.7% weak, 5.9% moderate, 37% strong) and CK20 positivity in 23% (5.1% weak, 3.4% moderate, 15% strong) of interpretable tumors. Of 8390 positive tumors, 1181 (14%) showed positivity for CK7 and CK20, 5380 (64%) showed positivity for CK7 alone, and 1829 (22%) showed positivity for CK20 alone. CK20 predominated in gastrointestinal tract, urothelial and Merkel cell carcinomas. CK7 was usually negative in prostate cancer and colorectal cancer. Combined evaluation of CK7/CK20 revealed the best diagnostic utility in CK20 positive tumors, where CK7 negativity is often linked to colorectal origin while CK7 positivity argues for urothelial origin or mucinous ovarian cancer. Associations with unfavorable tumor features were found for cytokeratin 7 loss in breast cancer of no special type, urothelial and renal cell carcinomas, for CK7 overexpression in high-grade serous ovarian and gastric cancer, and for CK20 overexpression in urothelial carcinoma. CK20 loss was linked to MSI in gastric (p = 0.0291) and colorectal adenocarcinoma (p < 0.0001). These analyses provide comprehensive data on the frequency of CK7 and CK20 immunostaining - alone or in combination - in human cancers. These data facilitate interpretation of CK7/CK20 immunostaining in cancers.

Expression of PD-1 on CD4+ Tumor-Infiltrating Lymphocytes in Tumor Microenvironment Associated with Pathological Characteristics of Breast Cancer

Objective

This study aimed to investigate the correlation of CD4⁺/PD-1⁺ or CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes with pathological characteristics in breast cancer patients.

Methods

A cross-sectional study consecutively recruited 133 patients with invasive ductal breast cancer. The expression of CD4, programmed cell death protein 1 (PD-1), CK7, CK20, E-cadherin, or Ki-67 was detected by immunohistochemistry. The associations between CD4⁺/PD-1⁺ or CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes and pathological characteristics were evaluated.

Results

Elderly patients intended to have a lower level of CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes (p < 0.05). Patients with positive E-cadherin expression had higher median cell counts of CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes than patients with negative E-cadherin expression (30/HPF versus 10/HPF, p < 0.05). Counts of CD4⁺/PD-1⁺ tumor-infiltrating lymphocytes had a significant correlation with Ki-67 index that the correlation coefficient was 0.29 (p = 0.001). Positive CK20 expression was related to a higher level of CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes than negative CK20 expression (73/HPF versus 30/HPF, p < 0.05).

Conclusion

CD4⁺/PD-1⁺ or CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes showed diverse association with pathological features of breast cancer. CD4⁺/PD-1⁺ tumor-infiltrating lymphocytes had a significant relationship with Ki-67 expression whereas CD4⁺/PD-1⁻ tumor-infiltrating lymphocytes had a significant relationship with E-cadherin expression. Further studies are warranted to explore the immunomodulatory effects of phenotypes of CD4⁺ T cell subsets in breast cancer.