Age-related phenotypes in breast cancer: A population-based study

Breast cancer in young (<40 years) is associated with a higher frequency of aggressive tumor types and poor prognosis. It remains unclear if there is an underlying age-related biology that contributes to the unfavorable outcome. We aim to investigate the relationship between age and breast cancer biology, with emphasis on proliferation. Clinico-pathologic information, immunohistochemical markers and follow-up data were obtained for all patients aged <50 (Bergen cohort-1; n = 355, not part of a breast screening program) and compared to previously obtained information on patients aged 50 to 69 years (Bergen cohort-2; n = 540), who participated in the Norwegian Breast Cancer Screening Program. Young breast cancer patients presented more aggressive tumor features such as hormone receptor negativity, HER2 positivity, lymph-node metastasis, the HER2-enriched and triple-negative subtypes and shorter survival. Age <40 was significantly associated with higher proliferation (by Ki67). Ki67 showed weaker prognostic value in young patients. We point to aggressive phenotypes and increased tumor cell proliferation in breast cancer of the young. Hence, tumors of young breast cancer patients may present unique biological features, also when accounting for screen/interval differences, that may open for new clinical opportunities, stratifying treatment by age.

A novel age-related gene expression signature associates with proliferation and disease progression in breast cancer

BACKGROUND AND OBJECTIVE

Breast cancer (BC) diagnosed at ages <40 years presents with more aggressive tumour phenotypes and poorer clinical outcome compared to older BC patients. Here, we explored transcriptional BC alterations to gain a better understanding of age-related tumour biology, also subtype-stratified.

METHODS

We studied publicly available global BC mRNA expression (n = 3999) and proteomics data (n = 113), exploring differentially expressed genes, enriched gene sets, and gene networks in the young compared to older patients.

RESULTS

We identified transcriptional patterns reflecting increased proliferation and oncogenic signalling in BC of the young, also in subtype-stratified analyses. Six up-regulated hub genes built a novel age-related score, significantly associated with aggressive clinicopathologic features. A high 6 Gene Proliferation Score (6GPS) demonstrated independent prognostic value when adjusted for traditional clinicopathologic variables and the molecular subtypes. The 6GPS significantly associated also with disease-specific survival within the luminal, lymph node-negative and Oncotype Dx intermediate subset.

CONCLUSIONS

We here demonstrate evidence of higher tumour cell proliferation in young BC patients, also when adjusting for molecular subtypes, and identified a novel age-based six-gene signature pointing to aggressive tumour features, tumour proliferation, and reduced survival-also in patient subsets with expected good prognosis.

Overexpression of miR-20a-5p in Tumor Epithelium Is an Independent Negative Prognostic Indicator in Prostate Cancer-A Multi-Institutional Study

Simple Summary

MicroRNAs (miRs) have critical regulatory roles in cell functions, and are involved in prostate cancer tumorigenesis. miR-20a-5p is a member of the oncogenic miR-17-92 cluster. Overexpressed miR-20a-5p has been shown to increase both cell proliferation and cell migration in cancers. The aim of our cohort study was to evaluate the prognostic role of miR-20a-5p in prostate cancer. We found miR-20a-5p associated with biochemical failure in tumor epithelium and tumor stroma. In the multivariable analysis miR-20a-5p in tumor epithelium was found to be an independent prognostic predictor for biochemical failure. In the functional studies, migration and invasion were significantly increased in miR-20a-5p transfected prostate cancer cell lines. In conclusion, high miR-20a-5p expression in tumor epithelium is a negative independent prognostic factor for biochemical failure in prostate cancer.

Abstract

Objective: assessing the prognostic role of miR-20a-5p, in terms of clinical outcome, in a large multi-institutional cohort study. Methods: Tissue microarrays from 535 patients’ prostatectomy specimens were constructed. In situ hybridization was performed to assess the expression level of miR-20a-5p in different tissue subregions: tumor stroma (TS) and tumor epithelium (TE). In vitro analysis was performed on prostate cancer cell lines. Results: A high miR-20a-5p expression was found negatively in association with biochemical failure in TE, TS and TE + TS (p = 0.001, p = 0.003 and p = 0.001, respectively). Multivariable analysis confirmed that high miR-20a-5p expression in TE independently predicts dismal prognosis for biochemical failure (HR = 1.56, 95% CI: 1.10–2.21, p = 0.014). Both DU145 and PC3 cells exhibited increased migration ability after transient overexpression of miR-20a-5p, as well as significant elevation of invasion in DU145 cells. Conclusion: A high miR-20a-5p expression in tumor epithelium is an independent negative predictor for biochemical prostate cancer recurrence.

High expression of miR-17-5p in tumor epithelium is a predictor for poor prognosis for prostate cancer patients

MicroRNAs (miRs) are small non-coding RNA molecules, which are involved in the development of various malignancies, including prostate cancer (PCa). miR-17-5p is considered the most prominent member of the miR-17-92 cluster, with an essential regulatory function of fundamental cellular processes. In many malignancies, up-regulation of miR-17-5p is associated with worse outcome. In PCa, miR-17-5p has been reported to increase cell proliferation and the risk of metastasis. In this study, prostatectomy specimens from 535 patients were collected. Tissue microarrays were constructed and in situ hybridization was performed, followed by scoring of miR-17-5p expression on different tumor compartments. High expression of miR-17-5p in tumor epithelium was associated with biochemical failure (BF, p < 0.001) and clinical failure (CF, p = 0.019). In multivariate analyses, high miR-17-5p expression in tumor epithelial cells was an independent negative prognostic factor for BF (HR 1.87, 95% CI 1.32-2.67, p < 0.001). In vitro analyses confirmed association between overexpression of miR-17-5p and proliferation, migration and invasion in prostate cancer cell lines (PC3 and DU145). In conclusion, our study suggests that a high cancer cell expression of miR-17-5p was an independent negative prognostic factor in PCa.

Low Expression of miR-424-3p is Highly Correlated with Clinical Failure in Prostate Cancer

Prostate cancer (PC) is a highly heterogenous disease and one of the leading causes of mortality in developed countries. Recently, studies have shown that expression of immune checkpoint proteins are directly or indirectly repressed by microRNAs (miRs) in many types of cancers. The great advantages of using miRs based therapy is the capacity of these short transcripts to target multiple molecules for the same- or different pathways with synergistic immune inhibition effects. miR-424 has previously been described as a biomarker of poor prognosis in different types of cancers. miR-424 is also found to target both the CTLA-4/CD80- and PD-1/PD-L1 axis. In the present study, the clinical significance of miR-424-3p expression in PC tissue was evaluated. Naïve radical prostatectomy specimens from 535 patients was used for tissue microarray construction. In situ hybridization was used to evaluate the expression of miR-424-3p and immunohistochemistry was used for CTLA-4 protein detection. In univariate- and multivariate analyses, low expression of miR-424-3p was significant associated with clinical failure-free survival, (p = 0.004) and p = 0.018 (HR:0.44, CI95% 0.22-0.87). Low expression of miR-424-3p also associated strongly with aggressive phenotype of PC. This highlight the importance of miR-424-3p as potential target for therapeutic treatment in prostate cancer.