Role of expression of cell cycle inhibitor p27 and MIB-1 in predicting lymph node metastasis in male breast carcinoma

Defining genomic, transcriptomic, proteomic, epigenetic, and phenotypic biomarkers with prognostic capability in male breast cancer: a systematic review

Although similar phenotypically, there is evidence that male and female breast cancer differ in their molecular landscapes. In this systematic review, we consolidated all existing prognostic biomarker data in male breast cancer spanning genetics, transcriptomics, proteomics, and epigenetics, and phenotypic features of prognostic value from articles published over a 29-year period (March 16, 1992, to May 1, 2021). We identified knowledge gaps in the existing literature, discussed limitations of the included studies, and outlined potential approaches for translational biomarker discovery and validation in male breast cancer. We also recognised STC2, DDX3, and DACH1 as underexploited markers of male-specific prognostic value in breast cancer. Finally, beyond describing the cumulative knowledge on the extensively researched markers oestrogen receptor-α, progesterone receptor, HER2, androgen receptor, and BRCA2, we highlighted ATM, CCND1, FGFR2, GATA3, HIF1-α, MDM2, TP53, and c-Myc as well studied predictors of poor survival that also aligned with several hallmarks of cancer.

Male Breast Carcinoma: A Clinical and Pathological Review

Male breast carcinomas (MBCs) are rare neoplasms that account for 0.1% of all male cancers. Still, there are 2000 new cases of MCB diagnosed annually in the United States. Because of its rarity, data regarding the etiology, risk factors, diagnosis, management, and prognosis of MBC are limited. MBC shares some similarities with female breast carcinoma (FBC). This review will address the important clinical, histopathological, immunohistochemical and molecular features, genetics, management, and prognosis of MBC.

Male breast cancer: risk factors, biology, diagnosis, treatment, and survivorship

BACKGROUND

The causes, optimal treatments, and medical/psychosocial sequelae of breast cancer in men are poorly understood.

DESIGN

A systematic review of the English language literature was conducted to identify studies relevant to male breast cancer between 1987 and 2012 and including at least 20 patients. Searches were carried out on PubMed using the title terms 'male breast cancer' or 'male breast carcinoma'.

RESULTS

Relevant published data regarding risk factors, biological characteristics, presentation and prognosis, appropriate evaluation and treatment, and survivorship issues in male breast cancer patients are presented. BRCA2 mutations, age, conditions that alter the estrogen/androgen ratio, and radiation are proven risk factors. Disease biology is distinct in men, but diagnostic approaches and treatments for men are generally extrapolated from those in women due to inadequate research in men. Survivorship issues in men may include sexual and hormonal side-effects of endocrine therapies as well as unique psychosocial impacts of the disease.

CONCLUSION

Further research is needed to address gaps in knowledge pertaining to care of male breast cancer patients and survivors.

Male breast cancer: is the scenario changing

Background

The overall incidence of male breast cancer is around 1% of all breast cancers and is on the rise. In this review we aim to present various aspects of male breast cancer with particular emphasis on incidence, risk factors, patho-physiology, treatment, prognostic factors, and outcome.

Methods

Information on all aspects of male breast cancer was gathered from available relevant literature on male breast cancer from the MEDLINE database over the past 32 years from 1975 to 2007. Various reported studies were scrutinized for emerging evidence. Incidence data were also obtained from the IARC, Cancer Mondial database.

Conclusion

There is a scenario of rising incidence, particularly in urban US, Canada and UK. Even though more data on risk factors is emerging about this disease, more multi-institutional efforts to pool data with large randomized trials to show treatment and survival benefits are needed to support the existing vast emerging knowledge about the disease.

Nonapical and cytoplasmic expression of interleukin-8, CXCR1, and CXCR2 correlates with cell proliferation and microvessel density in prostate cancer

PURPOSE

We characterized interleukin-8 (IL-8) and IL-8 receptor expression (CXCR1 and CXCR2) in prostate cancer to address their significance to this disease.

EXPERIMENTAL DESIGN

Immunohistochemistry was conducted on 40 cases of human prostate biopsy containing histologically normal and neoplastic tissue, excised from patients with locally confined or invasive androgen-dependent prostate cancer, and 10 cases of transurethral resection of the prostate material from patients with androgen-independent disease.

RESULTS

Weak to moderate IL-8 expression was strictly localized to the apical membrane of normal prostate epithelium. In contrast, membranous expression of IL-8, CXCR1, and CXCR2 was nonapical in cancer cells of Gleason pattern 3 and 4, whereas circumferential expression was present in Gleason pattern 5 and androgen-independent prostate cancer. Each of IL-8, CXCR1, and CXCR2 were also increasingly localized to the cytoplasm of cancer cells in correlation with advancing stage of disease. Cytoplasmic expression (but not apical membrane expression) of IL-8 in Gleason pattern 3 and 4 cancer correlated with Ki-67 expression (R = 0.79; P < 0.001), cyclin D1 expression (R = 0.79; P < 0.001), and microvessel density (R = 0.81; P < 0.001). In vitro studies on androgen-independent PC3 cells confirmed the mitogenic activity of IL-8, increasing the rate of cell proliferation through activation of both CXCR1 and CXCR2 receptors.

CONCLUSIONS

We propose that the concurrent increase in IL-8 and IL-8 receptor expression in human prostate cancer induces autocrine signaling that may be functionally significant in initiating and promoting the progression of prostate cancer by underpinning cell proliferation and angiogenesis.

The prognostic and therapeutic relevance of p27kip1 in Ewing's family tumors

PURPOSE

Ewing's family tumors (EFTs) display the characteristic fusion gene EWS-Fli1. We have reported EWS-Fli1 may promote the cell cycle progression accompanied by the suppression of the expression of cyclin-dependent kinase inhibitor p27(kip1) in EFT cells. Here, we describe the prognostic and therapeutic relevance of p27 in EFTs.

EXPERIMENTAL DESIGN

We examined tumor samples taken from 21 patients with primary EFTs for the expression of p27 protein immunohistochemically and evaluated its correlation with clinical outcome. We also investigated the usefulness of p27 as a therapeutic strategy in vitro and in vivo using p27 expression adenovirus. Finally, we examined the process of EWS-Fli1-mediated reduction of p27 expression.

RESULTS

Immunohistochemical analysis showed that a low expression level of p27 protein was related to poor event-free survival in an univariate analysis and that the expression level of p27 correlated more significantly with patient survival than several clinical factors in a multivariate survival analysis. Overexpression of p27 with the adenoviral vector remarkably inhibited the cell growth in all EFT cells tested and further induced apoptosis in the wild-type p53 EFT cells. In vivo studies demonstrated a reduction in tumor growth of EFT xenograft in nude mice treated with the intratumoral injection of p27-expressing adenovirus. EWS-Fli1 did not significantly affect the p27 promoter activity and p27 mRNA levels. However, the challenge of the proteasome inhibitor caused accumulation of p27 protein in EFT cells. These data strongly suggest EWS-Fli1 might attenuate p27 protein level via activation of the proteasome-mediated degradation pathway.

CONCLUSIONS

Our findings provide the first evidence of the prognostic relevance of p27 expression in EFTs. We propose p27 as a novel and powerful therapeutic factor for the molecular target therapy of EFTs.

Microenvironmental regulation of proliferation in multicellular spheroids is mediated through differential expression of cyclin-dependent kinase inhibitors

Multicellular spheroids composed of transformed cells are known to mimic the growth characteristics of tumors and to develop gradients in proliferation with increasing size. This progressive accumulation of quiescent cells is presumably an active process that occurs in response to the microenvironmental stresses that develop within the three-dimensional structure, and, yet, little is known regarding either the signals that induce the cell cycle arrest or the molecular basis for the halt in proliferation. We have previously reported that regulation of cyclin-dependent kinase (CDK) inhibitors (CKIs) differs in monolayer versus spheroid cell culture. In this study, we have examined the expression of three CKIs in EMT6 mouse mammary carcinoma and MEL28 human melanoma spheroids, as a function both of spheroid size and of location within the spheroid. We report that expression of the CKIs p18(INK4c), p21(waf1/cip1), and p27(Kip1) all increase as the spheroid grows and develops a quiescent cell fraction. However, by examining protein expression in discrete regions of the spheroid, we have found that only p18(INK4c) and p27(Kip1) expression positively correlate with growth arrest, whereas p21(waf1/cip1) is expressed predominantly in proliferating cells. Further analysis indicated that, in the quiescent cells, p18(INK4c) is found in increasing association with CDK6, whereas p27(Kip1) associates predominantly with CDK2. In MEL28 cells, CDK2 activity is completely abrogated in the inner regions of the spheroid, whereas in EMT6 cells, CDK2 activity decreases in accordance with a decrease in expression. We also observed a decrease in all cell cycle regulatory proteins in the innermost spheroid fraction, including CDKs, CKIs, and cyclins. Induction of CKIs from separate families, as well as their association with distinct target CDKs, suggests that there may be multiple checkpoints activated to ensure cell cycle arrest in non-growth-conducive environments. Furthermore, because very similar observations were made in both a human melanoma cell line and a mouse mammary carcinoma cell line, our results indicate that these checkpoints, as well as the signal transduction pathways that activate them, are highly conserved.