Exploring Collagen Parameters in Pure Special Types of Invasive Breast Cancer.

One of the promising tools to evaluate collagen in the extracellular matrix is the second-harmonic generation microscopy (SHG). This approach may shed light on the biological behavior of cancers and their taxonomy, but has not yet been applied to characterize collagen fibers in cases diagnosed as invasive breast carcinoma (BC) of histological special types (IBC-ST). Tissue sections from 99 patients with IBC-ST and 21 of invasive breast carcinoma of no special type (IBC-NST) were submitted to evaluation of collagen parameters by SHG. Tissue microarray was performed to evaluate immunohistochemical-based molecular subtype. In intratumoral areas, fSHG and bSHG (forward-SHG and backward-SHG) collagen parameters achieved their lowest values in mucinous, papillary and medullary carcinomas, whereas the highest values were found in classic invasive lobular and tubular carcinomas. Unsupervised hierarchical cluster analysis and minimal spanning tree using intratumoral collagen parameters allowed the identification of three main groups of breast cancer: group A (classic invasive lobular and tubular carcinomas); group B (IBC-NST, metaplastic, invasive apocrine and micropapillary carcinomas); and group C (medullary, mucinous and papillary carcinomas). Our findings provide further characterization of the tumor microenvironment of IBC-ST. This understanding may add information to build more consistent tumor categorization and to refine prognostication.

Copy number alterations associated with clinical features in an underrepresented population with breast cancer.

BACKGROUND: As the most incident tumor among women worldwide, breast cancer is a heterogeneous disease. Tremendous efforts have been made to understand how tumor characteristics as histological type, molecular subtype, and tumor microenvironment collectively influence disease diagnosis to treatment, which impact outcomes. Differences between populations and environmental and cultural factors have impacts on the origin and evolution of the disease, as well as the therapeutic challenges that arise due to these factors. We, then, compared copy number variations (CNVs) in mucinous and nonmucinous luminal breast tumors from a Brazilian cohort to investigate major CNV imbalances in mucinous tumors versus non-mucinous luminal tumors, taking into account their clinical and pathological features. METHODS: 48 breast tumor samples and 48 matched control blood samples from Brazilian women were assessed for CNVs by chromosome microarray. Logistic regression and random forest models were used in order to assess CNVs in chromosomal regions from tumors. RESULTS: CNVs that were identified in chromosomes 1, 5, 8, 17, 19, and 21 classify tumors according to their histological type, ethnicity, disease stage, and familial history. CONCLUSION: Copy number alterations described in this study provide a better understanding of the landscape of genomic aberrations in mucinous breast cancers that are associated with clinical features.

Multicenter Study Using Desorption-Electrospray-Ionization-Mass-Spectrometry Imaging for Breast-Cancer Diagnosis.

The histological and molecular subtypes of breast cancer demand distinct therapeutic approaches. Invasive ductal carcinoma (IDC) is subtyped according to estrogen-receptor (ER), progesterone-receptor (PR), and HER2 status, among other markers. Desorption-electrospray-ionization-mass-spectrometry imaging (DESI-MSI) is an ambient-ionization MS technique that has been previously used to diagnose IDC. Aiming to investigate the robustness of ambient-ionization MS for IDC diagnosis and subtyping over diverse patient populations and interlaboratory use, we report a multicenter study using DESI-MSI to analyze samples from 103 patients independently analyzed in the United States and Brazil. The lipid profiles of IDC and normal breast tissues were consistent across different patient races and were unrelated to country of sample collection. Similar experimental parameters used in both laboratories yielded consistent mass-spectral data in mass-to-charge ratios ( m/ z) above 700, where complex lipids are observed. Statistical classifiers built using data acquired in the United States yielded 97.6% sensitivity, 96.7% specificity, and 97.6% accuracy for cancer diagnosis. Equivalent performance was observed for the intralaboratory validation set (99.2% accuracy) and, most remarkably, for the interlaboratory validation set independently acquired in Brazil (95.3% accuracy). Separate classification models built for ER and PR statuses as well as the status of their combined hormone receptor (HR) provided predictive accuracies (>89.0%), although low classification accuracies were achieved for HER2 status. Altogether, our multicenter study demonstrates that DESI-MSI is a robust and reproducible technology for rapid breast-cancer-tissue diagnosis and therefore is of value for clinical use.

Collagen analysis by second-harmonic generation microscopy predicts outcome of luminal breast cancer.

Second-harmonic generation microscopy represents an important tool to evaluate extracellular matrix collagen structure, which undergoes changes during cancer progression. Thus, it is potentially relevant to assess breast cancer development. We propose the use of second-harmonic generation images of tumor stroma selected on hematoxylin and eosin-stained slides to evaluate the prognostic value of collagen fibers analyses in peri and intratumoral areas in patients diagnosed with invasive ductal breast carcinoma. Quantitative analyses of collagen parameters were performed using ImageJ software. These parameters presented significantly higher values in peri than in intratumoral areas. Higher intratumoral collagen uniformity was associated with high pathological stages and with the presence of axillary lymph node metastasis. In patients with immunohistochemistry-based luminal subtype, higher intratumoral collagen uniformity and quantity were independently associated with poorer relapse-free and overall survival, respectively. A multivariate response recursive partitioning model determined 12.857 and 11.894 as the best cut-offs for intratumoral collagen quantity and uniformity, respectively. These values have shown high sensitivity and specificity to differentiate distinct outcomes. Values of intratumoral collagen quantity and uniformity exceeding the cut-offs were strongly associated with poorer relapse-free and overall survival. Our findings support a promising prognostic value of quantitative evaluation of intratumoral collagen by second-harmonic generation imaging mainly in the luminal subtype breast cancer.

Expression of unusual immunohistochemical markers in mucinous breast carcinoma.

BACKGROUND: Mucinous breast carcinoma is characterized by the production of variable amounts of mucin. Some studies have addressed immunohistochemical characterization of mucinous breast carcinoma using a limited set of antibodies. However, the purpose of the present study was to investigate a larger panel of markers not widely used in daily practice and to determine their pathological implications. METHODS: Forty patients diagnosed with mucinous breast carcinoma were enrolled. An immunohistochemical study was performed on whole sections of paraffin embedded tissue, using antibodies for the following markers: estrogen receptor alpha and beta, progesterone receptor, androgen receptor, HER2, EGFR, Ki-67, E-cadherin, ß-catenin, p53, chromogranin, synaptophysin, GCDFP15, mammaglobin, and CDX2. RESULTS: The pure mucinous type was more prevalent in older patients and more frequently expressed GCDFP15. Capella type B presented more frequently with a high Ki-67 index and neuroendocrine differentiation. Although there was a lower frequency of vascular invasion and lymph node metastases in the pure type, the difference was not statistically significant. No case expressed CDX2 (a marker for gastrointestinal tumors), while 85% of the cases expressed at least one of the two typical breast markers (GCDFP15 and mammaglobin), suggesting that these markers may be reliably used for differential diagnosis. Expression of estrogen receptor beta was related to the presence of mucin cell producing lymph node metastasis, with potential prognostic and predictive value. CONCLUSION: our findings support the immunohistochemical homogeneity of mucinous breast carcinomas because only minor differences were found when subgrouping them into Capella types A and B or into types pure and mixed.

Interferon-inducible guanylate binding protein (GBP)-2: a novel p53-regulated tumor marker in esophageal squamous cell carcinomas.

TP53 mutations are common in esophageal squamous cell carcinomas (SCC). To identify biological markers of possible relevance in esophageal SCC, we (i) searched for genes expressed in a p53-dependent manner in TE-1, an esophageal SCC cell line expressing the temperature-sensitive TP53 mutant V272M, and (ii) investigated the expression of one of those genes, the interferon-inducible Guanylate Binding Protein 2 (GBP-2), in esophageal SCC tissues. Clontech Human Cancer 1.2 arrays containing 1,176 human cancer gene-related sequences were used to identify differentially expressed genes in TE-1 cells at permissive (32 degrees C) and nonpermissive (37 degrees C) temperatures. The expression of GBP-2 and IRF-1, its main transcriptional regulator, was analyzed by immunohistochemistry in a retrospective series of 41 esophageal SCC cases with a clear transition zone from noncancer, apparently normal epithelium to invasive cancer. The expression of the GBP-2 gene is consistently increased in TE-1 at 32 degrees C in a p53-dependent manner, as confirmed by inhibition of p53 expression by RNA interference. Increase in GBP-2 is accompanied by an increase in protein levels of IRF-1, the main transcriptional regulator of GBP-2, and in the formation of complexes between p53 and IRF-1. GBP-2 expression is significantly higher in esophageal SCC than in adjacent normal epithelium (p<0.01), in which GBP-2 staining is limited to the basal layer. Our results suggest that p53 up-regulates GBP-2 by cooperating with IRF-1. The association of GBP-2 expression with proliferative squamous cells suggests that GBP-2 may represent a marker of interest in esophageal SCC.