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Mitochondria modify their function and morphology to satisfy the bioenergetic demand of the cells. Cancer cells take advantage of these features to sustain their metabolic, proliferative, metastatic, and survival necessities. Understanding the morphological changes to mitochondria in the different grades of triple-negative breast cancer (TNBC) could help to design new treatments. Consequently, this research explored mitochondrial morphology and the gene expression of some proteins related to mitochondrial dynamics, as well as proteins associated with oxidative and non-oxidative metabolism in metastatic and non-metastatic TNBC. We found that mitochondrial morphology and metabolism are different in metastatic and non-metastatic TNBC. In metastatic TNBC, there is overexpression of genes related to mitochondrial dynamics, fatty-acid metabolism, and glycolysis. These features are accompanied by a fused mitochondrial morphology. By comparison, in non-metastatic TNBC, there is a stress-associated mitochondrial morphology with hyperfragmented mitochondria, accompanied by the upregulated expression of genes associated with the biogenesis of mitochondria; both of which are characteristics related to the higher production of reactive oxygen species observed in this cell line. These differences between metastatic and non-metastatic TNBC should provide a better understanding of metastasis and contribute to the development of improved specific and personalized therapies for TNBC.

Background: Triple negative breast cancer (TNBC) is characterized by heterogeneous metastatic and metabolic properties, which difficult the diagnosis and development of specific treatment. Therefore, the understanding of the mitochondria´s role in the different grades of TNBC could be relevant for the design of novel specific TNBC treatments. This research aimed to explore the mitochondria morphology and gene expression of proteins related to oxidative and non-oxidative metabolism in metastatic and non-metastatic TNBC cell lines. Methods: We performed a gene expression analysis of mitochondrial biogenesis, EMT and principal metabolism-related genes (Integrated DNA Technologies, CA, USA) in three breast cancer cell lines HCC-1395, MDA-MB-231 and MCF-12A. After the gene expression qPCR data mining, in sílico analisis were performed using confocal microscopy (Leica Microsystems,WZL, DE) in the cell lines where mitochondrial distribution, morphology, function and ROS production were measured. Results: The metastatic TNBC-cell line showed a preference for fatty acid biosynthesis and glycolytic metabolism since overexpression of genes related to both pathways was observed. These metabolism features were accompanied by a fused mitochondrial morphology and lower mitochondrial activity since was observed less mitochondrial density accompanied by the downregulated expression of biogenesis-related genes such as PGC1α. In contrast, the non-metastatic TNBC-cell line presented a hyperfragmented mitochondria, a stress associated mitochondrial morphology accompanied by upregulated expression of mitochondrial biogenesis-related genes, both characteristics related to the higher ROS production observed in this cell line. Conclusions: Metastatic TNBC was characterized by a mitochondrial function and morphology similar to control ranges with a metabolic gene program directed to glycolysis and FA usage. While mitochondria of the non-metastatic TNBC cell line was characterized by a higher density and potential, related to an increase of mitochondrial biogenesis, which in turn was associated with higher levels of ROS and with the consequence of a hyperfragmented mitochondrial morphology. These characteristics can provide a better understanding of the metastasis observed in TNBC and contribute to the development of a specific and personalized TNBC therapy. Key words: Triple Negative Breast Cancer, Mitochondria, Cell-metabolism. Citation Format: Claudia D Aguayo-Millán, Perla Perez-Trevino, Sandra Santuario-Facio, Alberto Camacho, Noemí Garcia, Rocio Ortiz-Lopez. Metastatic TNBC is highly associated with a fused mitochondrial morphology and a glycolytic and lipogenic metabolism programmation [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS19-25.

Nicotine is the major pharmacologically active substance in tobacco. Several studies have examined genotypes related to nicotine metabolism, but few studies have been performed in the Mexican population. The objective was to identify associations between gene variants in metabolizing enzymes and the urinary levels of nicotine metabolites among Mexican smokers. The levels of nicotine and its metabolites were determined in the urine of 88 young smokers from Mexico, and 167 variants in 24 genes associated with nicotine metabolism were genotyped by next-generation sequencing (NGS). Trans-3′-hydroxy-cotinine (3HC) and 4-hydroxy-4-(3-pyridyl)-butanoic acid were the most abundant metabolites (35 and 17%, respectively). CYP2A6*12 was associated with 3HC (p = 0.014). The rs145014075 was associated with creatinine-adjusted levels of nicotine (p = 0.035), while the rs12471326 (UGT1A9) was associated to cotinine-N-glucuronide (p = 0.030). CYP2A6 and UGT1A9 variants are associated to nicotine metabolism. 4HPBA metabolite was an abundant urinary metabolite in young Mexican smokers.

This research examines the spatial structure of a sample of breast cancer (BC) cases and their spatial interaction with contaminated areas in the Monterrey Metropolitan Area (MMA). By applying spatial statistical techniques that treat the space as a continuum, degrees of spatial concentration were determined for the different study groups, highlighting their concentration pattern. The results indicate that 65 percent of the BC sample had exposure to more than 56 points of PM10. Likewise, spatial clusters of BC cases of up to 39 cases were identified within a radius of 3.5 km, interacting spatially with environmental contamination sources, particularly with refineries, food processing plants, cement, and metals. This study can serve as a platform for other clinical research by identifying geographic clusters that can help focus health policy efforts., Breast Cancer, PM10, Spatial distribution, Cluster analysis, Mexico

Background: Triple negative breast cancer (TNBC) presents a very aggressive behavior with a high rate of metastasis. Overexpression of HMGA1 has been reported in TNBC and has been associated with the induction of the Epithelial-Mesenchymal transition (EMT) and metastasis. Therefore, HMGA1 is considered a master regulator of tumor progression in TNBC. The objective of this work was to know which genes are directly or indirectly regulated by HMGA1 to better understand their participation in EMT and their role in aggressive TNBC. Methods: We performed the silencing of the HMGA1 gene using siRNA Silencer® Select Pre-designed (s6667 HMGA1, 4390849 GAPDH, 4390843 Negative control, all from Thermo Fisher, MA, USA) in two TNBC cell lines, HCC-1395 and MDA-MB-231, and we observed the effect of this gene inhibition by microarray global expression analysis using GeneChip Human Genome U133 Plus 2.0 (Affymetrix, CA, USA), comparing the conditions of inhibition versus their own control without inhibition. After the microarray data mining, results for the HMGA1 and PRRX1 genes were validated by qPCR using the Prime Time® Primers for HMGA1 (Hs.PT.58.38699366), PRRX1 (Hs.PT.58.2820749), and GAPDH as endogenous gene (Hs.PT.39a.22214836) with SybrGreen reagent (Roche, Basel, Switzerland). The level of expression of the HMGA1 and PRRX1 proteins was analyzed by Western blot in nuclear protein extracts of each cell line before and after gene silencing. Finally, we performed an in silico analysis using the "Gene 2 promoter" tool in the Genomatix platform to search the promoters and binding proteins of the PRRX1 gene. Results: The silencing of HMGA1 in a non-metastatic TNBC-cell line, HCC-1395, showed deregulation of genes associated with cell proliferation and angiogenesis. Meanwhile the silencing in a TNBC-metastatic cell line, MDA-MB-231, resulted in the deregulation of genes involved in the formation and organization of the cytoskeleton, including the overexpression of PRRX1. Validation of the expression changes of HMGA1 and PRRX1 by qPCR and Western blot was performed and HMGA1 was confirmed to negatively regulate the PRRX1 gene expression. Through in silico studies, we identified several binding sites of HMGA1 to the PRRX1 promoter. Conclusions: The subexpression of PRRX1 is necessary for EMT to occur. In this study, we present the interesting finding that HMGA1 regulates the subexpression of PRRX1, as supported by the experiments of transcriptional and translational expression presented in this work. To our knowledge, this is the first report describing a regulatory role of HMGA1 on PRRX1, which could explain the metastatic capacity of cancers that overexpress HMGA1. Key words: Epithelial-Mesenchymal Transition, Triple Negative Breast Cancer, Mesenchymal-Epithelial Transition, Metastasis. Citation Format: Aguayo-Millán CD, Santuario-Facio SK, Treviño-Alvarado V, Calvo-Anguiano G, Rojas-Martínez A, Camacho-Morales A, Ortíz-López R. HMGA1 negatively regulates the expression of PRRX1 in triple negative breast cancer cells, which favors the progression to metastasis [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-08-04.

This article describes a 19-year-old female with mild facial dysmorphism, asociality, decreased school performance, and psychotic behavior in whom the karyotype showed an extra-chromosomal marker characterized as 9p24.3–9q21.11 duplication by array-CGH. The 69 Mbp duplicated segment in this patient includes the critical 9p duplication syndrome region, the GLDC and C90RF72 genes associated with psychotic behavior and other conduct disorders, and a potential locus for autism.

Introduction: Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype, lacking expression of estrogen, progesterone and HER2 receptors. Evidence suggests that TNBC present more frequently in young African-American and Hispanic women, with lower socioeconomic status, hormonal environment and obesity. To this date, there are no studies that have compared TNBC versus nonTNBC in a homogeneous population. Comparison of these groups may help to identify genes that are key hallmarks in TNBC patients. Objective: To analyze the expression profile of TNBC versus nonTNBC in a homogeneous population from northwestern Mexico, in order to find distinctive biological pathways characteristics to TNBC. Methods: A prospective study was conducted involving a total of 50 patients (25 TNBC and 25 nonTNBC) undergoing neoadjuvant chemotherapy (NAC) for breast cancer. Both groups were similar in mean age at diagnosis (51 vs 47 years), mean of glucose levels (107 mg/dl vs 104 mg/dl) and BMI (28 vs 29) for TNBC and nonTNBC respectively. Core biopsies were obtained for histological diagnosis and gene expression, total RNA was isolated and expression profiling performed. Some of the differentially expressed genes were selected and validated by qPCR Results: Seventy percentage of the population presented BMI > 25. We identified a genomic profile expression composed of 40 genes associated with TNBC phenotype. Out of 40 genes, 9 were overexpressed (FOXC1, PRKX/PRKY, UGT8, BCL11A, HMGA1, LPIN1, FAM171A1, HAPLN3, y ANKRD11) and 31 under-expressed. Interestingly, some of these genes were previously associated to breast cancer. HMGA1, PRKX and LPIN1 participate in the insulin metabolism, UGT8 in the sphingolipids metabolism, while two others are transcription factors associated with metastasis and poor prognosis (FOXC1) and tumor growth (BCL11A). Conclusions: To our knowledge this is the first study in Latin American woman reporting a genomic signature for TNBC strongly associated with aberrant metabolism itself, such as seen in obesity. Understanding cell metabolism may help to clarify the mechanism for tumor development and progression in TNBC patients. Citation Format: Santuario-Facio SK, Cardona-Huerta S, Perez-Paramo YX, Treviño V, Hernandez-Cabrera F, Rojas-Martinez A, Psdilla-Rivas G, Muñoz-Maldonado G, Barbosa-Quintana A, Barbosa-Quintana O, Garza-Guajardo R, Gonzalez-Guerrero JF, Martinez-Rodriguez JL, Ortiz-López R. Gene expression profile of triple negative breast cancer in patients highlight biomarkers involved in cell metabolism. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-03-20.

Triple negative breast cancer (TNBC) is a subtype of breast cancer (BC) with a heterogeneous nature that stains negatively for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor 2 (HER2) during immunohistochemistry. Approximately 15–20% of all cases of breast cancer are triple negative phenotypes. Compared to patients with hormone receptor-positive cancer, TNBC patients are typically younger (