Myofibroblastic reaction is a common event in metastatic disease of breast carcinoma: a descriptive study

Quantification of stromal reaction in breast carcinoma and its correlation with tumor grade and free progression survival

Cancer progression results from a complex interplay between tumor cells and the extracellular milieu. In breast carcinoma, the stromal microenvironment has been suggested to play a major role in promoting tumor growth, progression, and invasion. The stroma of 154 resected specimens of invasive breast carcinoma of no special type was quantified using a digital image analyzer. Statistical analyses were performed between the quantity of stroma and survival, as well as between progression-free survival and clinicopathological data. Levels of myofibroblastic stroma varied from 0-46%, with a median of 15.1% and a standard deviation of 7.5. The myofibroblastic stromal reaction was statistically greater in grade 2 and 3 tumors (p = 0.029). Furthermore, there was a trend for worse progression-free survival in the group of node-negative tumors with strong smooth-muscle actin stromal expression (Log rank = 0.075). The present study demonstrates that the myofibroblastic reaction of breast invasive carcinoma of no special type is not merely a passive reaction, but seems to be an integral part of the neoplastic process by facilitating tumor progression and invasion. Additional, larger studies on mechanisms of stromal change are needed and may potentially lead to novel treatments.

Expression of the glucocorticoid receptor in breast cancer-associated fibroblasts

Cancer- associated fibroblasts (CAFs) are actively involved in breast carcinoma. Our previous study demonstrated that the majority of these CAFs were smooth muscle actin (SMA) positive and were therefore termed peritumoral myofibroblast (PMY). Glucocorticoid, linked or not with its receptor (GR), has been postulated to serve a major role in normal breast and breast carcinoma; however, their role in CAFs remains poorly understood. The aim of the present study was to assess the presence of GR in breast CAFs and particularly in PMY in 56 cases of invasive breast carcinoma in correlation with clinicopathological parameters, by immunohistochemistry. GR was observed in CAFs in 51 cases (91%) and were more frequent in luminal A subtype (19/19 cases; 100%). The stromal expression was statistically correlated with the tumor grade (P=0.03), the Ki-67 index (P=0.003) and the presence of GR in the epithelial component (P=0.01). The demonstration of a frequent expression of GR in breast CAFs may serve as an interesting target for future therapeutics for the regulation of the tumoral breast microenvironment.

Patients with hepatic breast cancer metastases demonstrate highly specific profiles of matrix metalloproteinases MMP-2 and MMP-9 after SIRT treatment as compared to other primary and secondary liver tumours

BACKGROUND

Patients with primary and metastatic liver malignancies represent a highly heterogeneous patient pool characterised by some of the shortest life expectancies amongst oncology patients. Investigation and better understanding of liver malignancies is an emerging field which requires high-quality multidisciplinary research and collaboration.

METHODS

A study of 158 patients with primary hepatic carcinomas and secondary liver metastases, altogether 15 cancer types of different origin, who underwent selective internal radiation therapy (SIRT) with Yttrium(90) or transarterial chemoembolisation, was undertaken in an effort to detect distinguishing features with respect to activity profiles of both blood matrix metalloproteinase (MMP-2 and MMP-9).

RESULTS

Noteworthy, stratification of all hepatic cancer groups with respect to MMP-2 and MMP-9 activities revealed characteristic patterns specifically in patients with hepatic breast cancer metastases who had undergone SIRT. In contrast to all other groups, these patients demonstrated well-consolidated profiles of both MMPs, reflecting a common feature, namely an immediate and durable increase of their activity after the SIRT treatment. Although the total number of patients in the breast cancer group is relatively small (15 patients), since increased activities of MMP-2 and MMP-9 are well known prognostic factors for poor outcomes of oncologic patients, the significance and clear group-specificity (from 15 ones investigated here) of this previously unanticipated finding requires particular attention and further investigations. Particularly important is to determine, whether this increase of the metalloproteinase activity was provoked by SIRT, as well as whether special selection criteria are required for patients with breast cancer metastases to the liver who are being considered for SIRT.

CONCLUSIONS

It is recommended that a more focused, multidisciplinary and large-scaled investigations of the possible adverse effects of SIRT in patients with advanced metastatic disease of breast cancer be undertaken, with an appropriate patients' stratification, set-up of the relevant patient profiles and disease modelling.

Relationship between ultrasound elastography and myofibroblast distribution in breast cancer and its clinical significance

The study investigated the relationship between ultrasound elastography (USE) scoring and myofibroblast distribution with expression features of α-SMA + /CD34− in patients of Uyghur and Han ethnicities with breast masses in Xinjiang, China. The data was used to evaluate its clinical significance in the early diagnosis of breast cancer. A total of 300 patients with breast masses were included in the study, which involved conventional sonography and USE, with histopathologic diagnosis as the reference standard. Myofibroblast distribution was investigated by detecting the expression levels of α-SMA and CD34 in lesions using immunohistochemistry and real-time PCR. Out of 300 lesions, 185 were histologically malignant and 115 benign. The mean elasticity score for malignant lesions was significantly higher than for benign lesions. The expression level of α-SMA was elevated while the expression level of CD34 was lower in malignancies, compared with benign lesions. The expression of α-SMA was positively associated with the USE scores, while a negative relationship was observed between CD34 expression and USE scoring. The combination of USE and molecular diagnosis provides a promising modality for the early diagnosis and evaluation of the risks in particular types of breast cancer.

Stromal expression of matrix metalloproteinase 2 in cancer-associated fibroblasts is strongly related to human epidermal growth factor receptor 2 status in invasive breast carcinoma

The peritumoral stroma and cancer-associated fibroblasts (CAFs) have been suggested to play an important role in breast tumorigenesis. The specific immunohistochemical characteristics of the stromal component according to the breast carcinoma subtype surrogates of molecular classes is poorly understood. In the present study, immunohistochemical staining was used to evaluate the expression of matrix metalloproteinase 2 (MMP2), which is one of the most important proteins considered to facilitate tumor invasion, in a series of invasive breast carcinomas according to subtype: Luminal A, luminal B, luminal-HER2, HER2-enriched and triple-negative. A significant increase in MMP2 expression was demonstrated in tumors known to exhibit a more aggressive metastatic behavior, such as luminal HER2 (37%), HER2-enriched (30%) and triple-negative tumors (17%), compared with the luminal A (6%) or luminal B (13%) subtypes. Our data indicated that the CAFs associated with different breast subtypes exhibit different specific properties to facilitate tumor invasion.

Macrophage migration inhibitory factor involvement in breast cancer (Review)

Macrophage migration inhibitory factor (MIF) is a pleiotropic inflammatory cytokine involved in many cellular processes and in particular carcinogenesis. Here, we review the experimental and clinical published data on MIF and its pathways in breast cancer. Experimental data show that MIF is overexpressed in breast cancer cells (BCC) due, at least partly, to its stabilization by HSP90 and upregulation by HIF-1α. MIF interacts with its main receptor CD74 and its co-receptor CXCR-4, both overexpressed, promoting cell survival by PI3K/Akt activation, a possible link with EGFR and HER2 pathways and inhibition of autophagy. Besides these auto- and paracrine effects on BCC, MIF interacts with BCC micro-environment by several mechanisms: immunomodulation by increasing the prevalence of immune suppressive cells, neo-angiogenesis by its link to HIF-1, and finally BCC transendothelial migration. Clinical studies show higher levels of MIF in breast cancer patients serum compared to healthy volunteers but without obvious clinical significance. In breast cancer tissue, MIF and CD74 are overexpressed in the cancer cells and in the stroma but correlations with classical prognostic factors or survival are elusive. However, an inverse correlation with the tumor size for stromal MIF and a positive correlation with the triple receptor negative tumor status for stromal CD74 seem to be showed. This set of experimental and clinical data shows the involvement of MIF pathways in breast carcinogenesis. Several anti-MIF targeted strategies are being explored in therapeutic goals and should merit further investigations.