Quantitative label-free mass spectrometry using contralateral and adjacent breast tissues reveal differentially expressed proteins and their predicted impacts on pathways and cellular functions in breast cancer.

Proteins play an essential role in the biological processes associated with cancer. Their altered expression levels can deregulate critical cellular pathways and interactive networks. In this study, the mass spectrometry-based label-free quantification followed by functional annotation was performed to investigate the most significant deregulated proteins among tissues of primary breast tumor (PT) and axillary metastatic lymph node (LN) and corresponding non-tumor tissues contralateral (NCT) and adjacent (ANT) from patients diagnosed with invasive ductal carcinoma. A total of 462 proteins was observed as differentially expressed (DEPs) among the groups analyzed. A high level of similarity was observed in the proteome profile of both non-tumor breast tissues and DEPs (n = 12) were mainly predicted in the RNA metabolism. The DEPs among the malignant and non-tumor breast tissues [n = 396 (PTxNCT) and n = 410 (LNxNCT)] were related to pathways of the LXR/RXR, NO, eNOS, eIF2 and sirtuins, tumor-related functions, fatty acid metabolism and oxidative stress. Remarkable similarity was observed between both malignant tissues, which the DEPs were related to metastatic capabilities. Altogether, our findings revealed differential proteomic profiles that affected cancer associated and interconnected signaling processes. Validation studies are recommended to demonstrate the potential of individual proteins and/or pathways as biological markers in breast cancer. SIGNIFICANCE: The proteomic analysis of this study revealed high similarity in the proteomic profile of the contralateral and adjacent non-tumor breast tissues. Significant differences were identified among the proteome of the malignant and non-tumor tissue groups of the same patients, providing relevant insights into the hallmarks, signaling pathways, biological functions, and interactive protein networks that act during tumorigenesis and breast cancer progression. These proteins are suggested as targets of relevant interest to be explored as potential biological markers related to tumor development and metastatic progression in the breast cancer disease.

Comparative Proteomics of Tumor and Paired Normal Breast Tissue Highlights Potential Biomarkers in Breast Cancer.

BACKGROUND/AIM: Breast cancer is the most common type of cancer among women worldwide, and about 57,000 new cases are expected for the Brazilian population in 2015. Elucidation of protein expression and modification is essential for the biological understanding, early diagnosis and therapeutics of breast cancer. The main objectives of the study are comparison between the proteome of tumor and paired non-tumor breast cancer tissues, describing all identified proteins, highlighting the ones most differentially expressed and comparing the data with existing literature. MATERIALS AND METHODS: The five paired samples from patients with invasive ductal carcinoma were analyzed by 2-DE and MS. RESULTS: We collected 161 identified spots corresponding to 110 distinct proteins. Forty-three differentially-expressed spots were common to at least two samples, and the ten proteins with the highest-fold changes were CASPE, ENOG, TPM1, CAPG, VIME, TPM3, TRFE, PDIA6, WDR61 and PDIA3. Metabolic enzymes and proteins with binding functions were the most representative functional classes of proteins with increased and decreased expression in tumor tissue respectively. CONCLUSION: Taking the fold change as a parameter, we point to future targets to be studied by functional methods in a search for biomarkers for initiation and progress of breast cancer.

Comparative proteomics of primary breast carcinomas and lymph node metastases outlining markers of tumor invasion.

BACKGROUND: Lymph node metastasis is an important clinicopathological parameter for breast cancer prognostication and treatment. Although the development of metastasis is common in axillary lymph nodes, the mechanisms underlying the locoregional spread are yet poorly understood. In the present study, we outline the involvement of proteins in tumor invasion by comparing the proteome profile of primary breast tumors (PBT) against that of lymph node metastasis (LNM). PATIENTS AND METHODS: The comparative proteome analyses of seven paired samples were performed using two-dimensional gel electrophoresis (2DE) and mass spectrometry (MS). RESULTS: Recurrent proteins were differentially expressed in PBT and LNM across patients. Higher levels of 1433G, 1433T, K2C8, PSME2, SNAA, TPM4, TRFE and VIME were observed in primary tumors compared to the metastatic site. On the other hand, higher levels of ALDH2 and GDIR2 were identified in metastasis related to tumors. These proteins provide a new insight on breast cancer research. CONCLUSION: Our achievements strengthened previous omics-based studies and also support the validation of potential markers of tumor invasion and metastasis.

Fragmented adipose tissue transplanted to craniofacial deformities induces bone repair associated with immunoexpression of adiponectin and parathyroid hormone 1-receptor.

Objective : This study analyzed the influence of autogenous white adipose tissue on bone matrix development in critical-size defects created in rabbit calvaria. Materials and methods : A 15-mm-diameter defect was created in the calvaria of 42 rabbits. Twenty-one rabbits were treated with 86 mm(3) of immediate transplant of fragmented white subcutaneous adipose tissue (WSAT); the others constituted the control group (sham). The animals were euthanized at 7, 15, and 40 days postsurgery (n = 7), and the histological data were analyzed by histomorphometry and immunohistochemistry using the anti-adiponectin and parathyroid hormone 1-receptor (PTH1R) antibodies. Results : The calvariae treated with fragmented WSAT demonstrated significant bone formation. These results coincided with the significant presence of immunopositivity to adiponectin and PTH1R in loci, which in turn coincided with the increase in bonelike matrix deposited both in fat tissue stroma and adipocytes' cytoplasm. In contrast, the control group revealed a small amount of bone-matrix deposition and presented scarce PTH1R expression and a lack of immunostain for adiponectin. Conclusion : These results indicate that transplant of fragmented white subcutaneous adipose tissue may be an alternative to treatment of craniofacial bone deformities because adipose tissue suffers from osseous metaplasia and exhibits immunoexpression of the adiponectin and PTH1R, which are proteins associated with bone metabolism.

Bone healing in critical-size defects treated with immediate transplant of fragmented autogenous white adipose tissue.

This study analyzed the influence of fragmented autogenous white subcutaneous adipose tissue (WSAT) on bone healing in critical-size defects created in rabbit calvaria. A 15-mm diameter defect was created in the calvaria of 42 rabbits, which were treated with 86 mm3 WSAT grafts or filled only with blood clots (control). Animals were euthanized at 7, 15, and 40 days postsurgery (n = 7), and the data were analyzed using histomorphometry and immunohistochemistry using the anti-CD34 and bone morphogenetic protein-2 (BMP2) antibodies. The calvaria treated with only blood clots demonstrated positivity to CD34 concentrated in endothelial cells, whereas the BMP2 were restricted to the borders of the defects. In contrast, the group treated with WSAT revealed fatty cells exhibiting positivity to BMP2 both in membrane and cytoplasm and intense quantities of stromal spindle cells that exhibited positivity to CD34 simultaneously to BMP2; these results together coincided with a larger bone matrix deposited in all postsurgery periods analyzed. These results revealed that the WSAT may be an alternative to craniofacial bone reconstruction because the adipose tissue exhibited prominent immunoexpression of BMP2, which was coexpressed with stromal CD34+ cells, indicating the plasticity of CD34+ stem cells into osteoblasts, and in the adipocytes, facts that suggest bone tissue development through cellular transdifferentiation from adipocytes.

Nonprocessed adipose tissue graft in the treatment of dehiscence bone defects in rabbit tibiae: a pilot study.

OBJECTIVE: To evaluate the bone repair of surgically created dehiscence-type defects (3 × 5 mm) around dental implants in rabbit tibia using nonprocessed adipose tissue graft or autogenous bone graft. MATERIALS AND METHODS: The bone defects were randomly assigned to 3 groups: blood clot (C), autogenous bone (AB), and nonprocessed adipose tissue (AT). After 3 months, the animals were euthanized. Histomorphometric analyses were performed, and the results were analyzed with analysis of variance and Tukey tests (P ≤ 0.05). Statistics were performed for the percentage of the bone-to-implant contact (BIC) and bone area (BA) within the limits of the threads. RESULTS: The results for BIC in the AT (37.75% ± 28.03%) and C (40.57 ± 13.71%) groups were statistically similar, whereas the AB group had the greatest percentage of BIC (83.37% ± 11.85%). For all groups, the BA percentage was similar (61.48% ± 30.89% in AT; 72.90% ± 14.10% in C; 84.23% ± 11.96% in AB), with no statistically significant differences. CONCLUSION: Nonprocessed adipose tissue is not a comparable substitute for autogenous bone in the treatment of dehiscence bone defects around titanium dental implants.

Differential loss of heterozygosity profile on chromosome 3p in ductal and lobular breast carcinomas.

The 2 main histologic types of infiltrating breast cancer, invasive lobular and invasive ductal carcinoma, are morphologically and clinically distinct. Studies revealed that different patterns of gene expression and loss of heterozygosity can also distinguish these 2 subtypes. A whole-genome study using single nucleotide polymorphism array found a significantly higher frequency of loss of heterozygosity on 3p in invasive ductal carcinoma when compared with invasive lobular carcinoma. In this study, we performed a loss of heterozygosity analysis of the 3p chromosome region in ductal and lobular breast tumors. Seven microsatellite markers were evaluated in a series of 136 sporadic breast cancer cases (118 invasive ductal carcinoma and 18 invasive lobular carcinoma) and correlated with clinical-histopathologic parameters from the patients. A significantly higher frequency of loss of heterozygosity was observed in invasive ductal carcinoma (65.3%) when compared with invasive lobular carcinoma (38.9%). When the markers were analyzed separately, loss of heterozygosity at 3 of them, D3S1307 in 3p26.3, D3S1286 in 3p24.3, and D3S1300 in 3p14.2, were significantly more frequent in ductal than in lobular tumors. D3S1307 marker showed the highest frequency of loss of heterozygosity in invasive ductal carcinoma (46.2%), and associations between loss of this marker and loss of estrogen and progesterone receptors were found in these samples. Our results confirm the observations that invasive ductal carcinoma has a higher frequency of loss of heterozygosity events across the 3p region than invasive lobular carcinoma and show that specific losses on 3p26.3, 3p24.3, and 3p14.2 regions are more frequent in ductal than in lobular tumors. We discuss our data in relation to the known tumor suppressor genes that are mapped at the 3p loci investigated and their present relevant roles in breast cancer.

Platelet-rich plasma diminishes calvarial bone repair associated with alterations in collagen matrix composition and elevated CD34+ cell prevalence.

The interaction between platelets and both type I and III collagens plays an important role in modulating platelet adhesion and aggregation, also contributing to the chemotaxis of CD34+ cells. The interaction with type III collagen can maintain high levels of collagen and alter the biology of bone repair when the PRP is used. The aim of this study was to evaluate the effect of platelet-rich plasma (PRP) and autograft on the presence of type III and type I collagens, the ratio between them, as well as the presence of CD34+ progenitor cells, while comparing these results by means of a histomorphometric analysis of the bone tissue. Four bone defects (8.0mm in diameter and 2.0mm in depth) were produced on the calvarium of 23 rabbits. The surgical defects were treated with either autogenous bone grafts, autogenous bone grafts with PRP and PRP alone. Animals were euthanized at 2, 4 or 6 weeks post-surgery. Histological, histomorphometric and immunohistochemical analyses were performed to assess repair time, as well as the expression of type I and III collagens, and number of progenitor CD34+ cells. Data were analyzed using the ANOVA and Student-Newman-Keuls test (alpha=5%). An enlarged granulation and medullary tissue areas in the PRP groups were observed. The use of PRP in this study hindered bone deposition, also enhanced type III to type I collagen ratio and the chemotaxis of CD34+ progenitor cells, similarly to a thrombogenic effect.

Comprehensive cytogenetic evaluation of a mature ovarian teratoma case.

Mature ovarian teratomas are benign ovarian germ cell tumors that usually present with a normal karyotype. There are very few reports describing chromosomal abnormalities in these tumors, none of which are recurrent. In this study we report on a mature teratoma case with clonal chromosomal alterations which include monosomies of chromosomes 6, 14, 16, and 21; trisomies of chromosomes 14 and 21; and deletions of Xq, 5p, 16p, and 17p. Comparative genomic hybridization evaluation of the sample revealed a normal profile. These findings are discussed together with the cytogenetic reports on other cases of ovarian teratomas described in the literature.