Double-positive in triple-negative? How significant is basal cytokeratin expression in breast cancer?

Programmed death ligand-1 protein expression difference in basal like and non-basal like triple negative breast cancer and its association with disease free survival and overall survival: A systematic review

The study aims to summarize the literature and explore the strength of evidence for PD-L1 expression difference in basal like TNBC and non-basal like TNBC, and association of PD-L1 expression with disease free survival and overall survival in each group. A systematic search of the original research literature through November 29^th, 2020, reported according to PRISMA guideline. Eligible studies investigated must have a primary outcome and at least one secondary outcome. Two reviewers independently searched, selected, and assessed quality of studies and risk of bias. Any discrepancies will be resolved by consensus or by consulting a third and fourth author. A total of 6813 articles were screened from which five articles were selected and assessed for quality of studies and risk of bias. Of 5 articles, no similar findings are found regarding the level of PD-L1 expression and its correlation with recurrence and overall survival. There is not enough substantial evidence to support the difference PD-L1 protein expression level in basal and non-basal like TNBC and its association with recurrence and overall survival. Hence, further studies are needed specifically to focus on this problem.

Identification of cytokeratin24 as a tumor suppressor for the management of head and neck cancer

To improve management of head and neck squamous cell carcinoma patients, we need to increase our understanding of carcinogenesis, to identify biomarkers, and drug targets. This study aimed to identify novel biomarkers by providing transcriptomics profiles of matched primary tumors, lymph node metastasis, and non-malignant tissue of 20 HNSCC patients as well as by bioinformatic analyses of a TCGA HNSCC cohort, comprising 554 patients. We provide cancer cell signaling networks differentially expressed in tumors versus metastases, such as mesenchymal-epithelial transition, and structural integrity networks. As a proof of principle study, we exploited the data sets and performed functional analyses of a novel cytokeratin, cytokeratin24 (cKRT24), which had not been described as biomarker for tumors before. Survival analysis revealed that low cKRT24 expression correlated with poor overall survival in HNSCC. Experimentally, downregulation of cKRT24 in primary tumors, metastases, and HNSCC cell lines was verified on mRNA and protein level. Cloning and ectopic overexpression of cKRT24 not only affected viability and growth of HNSSC cell lines, but also inhibited tumor growth in murine xenograft studies. We conclude that cKRT24 functions as a tumor suppressor in HNSCC, and may serve as an additional prognostic biomarker and novel target to support current HNSCC treatments.