Diindolylmethane Promotes Metabolic Crisis and Enhances the Efficacy of Centchroman in Breast Cancer: A 1H NMR-Based Approach.

Diindolylmethane (DIM) is a key metabolite of indole-3-carbinol found in cruciferous vegetables such as broccoli, cauliflower, and cabbage. DIM has been known for its anti-cancerous activity through various mechanisms. Most cancer cells, including triple-negative breast cancer (TNBC), adapt distinct metabolic reprogramming for rapid growth and proliferation. Hence, targeting metabolic dysregulation may provide a favorable therapeutic condition for the treatment of TNBC. Earlier, we found that DIM increases the intracellular accumulation of Centchroman (CC), a potential anticancer agent, thereby enhancing the therapeutic potential of CC against breast cancer. However, the role of DIM in regulating TNBC cellular metabolism remains unknown. In the current study, we investigated the potential therapeutic interventions of DIM in TNBC and its metabolic reprogramming in enhancing the efficacy of CC. We found that DIM induced metabolic catastrophe in TNBC cells by regulating aerobic glycolysis and intermediate metabolism. Further, the DIM and CC combination significantly inhibited the TNBC tumor growth in the 4T1-syngeneic model. The inhibition of tumor growth was associated with the downregulation of key aerobic glycolysis mediators such as PKM2, GLUT1, and hypoxia-inducible factor 1α (HIF-1α). This is a first-of-a-kind investigation linking DIM with aerobic glycolysis regulation and enhancing the treatment efficacy of CC against TNBC. Therefore, these findings suggest that DIM-based nutraceuticals and functional foods can be developed as adjuvant therapy for treating metabolically dysregulated TNBC.

Dietary Piperine Suppresses Obesity-Associated Breast Cancer Growth and Metastasis by Regulating the miR-181c-3p/PPARα Axis.

Adipocyte-derived leptin activates multiple oncogenic signaling, leading to breast cancer cell progression and metastasis. Hence, finding effective strategies to inhibit the oncogenic effects of leptin would provide a novel approach for disrupting obesity-associated breast cancer. In the current study, we explored the role of piperine, a major plant alkaloid from Piper nigrum (black pepper), against leptin-induced breast cancer. Piperine treatment significantly inhibited leptin-induced breast cancer cell proliferation, colony formation, migration, and invasion. We found that piperine downregulated the expression of PPARα, a predicted target of miR-181c-3p. Mechanistically, piperine potentiates miR-181c-3p-mediated anticancer potential in leptin-induced breast cancer cells. Interestingly, the knockdown of PPARα reduced the proliferative potential of leptin-induced breast cancer cells. Further, oral administration of piperine inhibited breast tumor growth in diet-induced obese mice, accompanied by the upregulation of miR-181c-3p and downregulation of PPARα expression. Together, piperine represents a potential candidate for further development as an anticancer agent for treating obesity-associated breast cancer.

miR-145-5p as a predictive biomarker for breast cancer stemness by computational clinical investigation.

BACKGROUND: Breast tumors enriched with breast cancer stem cells (BCSCs), play a crucial role in metastasis and tumor relapse. Hence, targeting BCSCs may lead to efficacious breast cancer therapy. BCSCs have a unique expression of stemness markers, including Nanog, POU5F1, SOX2, and CD44, which play a vital role in cancer stem cell properties. However, the regulation of microRNAs (miRNAs)-mediated cancer stem cell marker expressions is largely unclear. METHODS: MIENTURNET was used to predict miRNA-target interactions. miR-TV, UALCAN and GEPIA databases were used to analyze the expression of miR-145-5p and SOX2. Survival analysis was obtained by cBioportal, KM plotter and Breast Cancer Gene-Expression Miner. RNAComposer was used to perform miRNA-mRNA duplex prediction. In vitro mRNA and miRNA analysis was performed by qRT-PCR. RESULTS: It was observed that miR-145-5p was the common miRNA targeting stemness markers. miR-145-5p expression was found to be lower in breast cancer patients compared to healthy subjects. Based on survival analysis, low expression of miR-145-5p and high expression of SOX2 led to a poor overall survival rate in breast cancer patients. Pathway enrichment analysis indicated that SOX2 was highly enriched with transcription factors. Moreover, SOX2 expression level was also upregulated in axillary metastatic lymph nodules. Further, in vitro ectopic expression of miR-145-5p by its mimic downregulated the SOX2 expression compared to the control mimic. Overall, SOX2 was a direct target for miR-145-5p as per the binding and minimal-free energy. CONCLUSIONS: In this study, miR-145-5p targeting SOX2 was identified as a potential predictive biomarker for breast cancer stemness.

Genome-wide analysis reveals miR-3184-5p and miR-181c-3p as a critical regulator for adipocytes-associated breast cancer.

Obesity is considered as an independent risk factor for breast cancer (BCa) and plays a major role in the breast tumor microenvironment. The etiology and mechanisms by which obesity contributes to BCa development is not yet understood. Herein, we show that in vitro coculture of BCa cells with mature adipocytes (MA-BCa) increased proliferation, migration, and invasive phenotype of BCa cells. MA-BCa coculture led to increased production of proinflammatory cytokines and chemokines. To identify microRNAs (miRNAs) in BCa cells that are modulated by the presence of adipocytes, we used small RNA sequencing analysis. Sequencing data revealed that 98 miRNAs were differentially expressed in MA-BCa. Among them, miR-3184-5p and miR-181c-3p were found to be the most upregulated and downregulated miRNAs, and direct targets are FOXP4 and PPARα, respectively. In vitro functional assays using a combination of miR-3184-5p inhibitor and miR-181c-3p mimic synergistically decreased adipocytes-induced cell proliferation and invasive capacity of BCa cells. Gene Set Enrichment analysis indicated that transcription factors were highly enriched followed by protein kinases, oncogene, and protein regulators in MA-BCa. GeneGo Metacore pathway analysis uncovered "NOTCH-induced EMT pathway" was found to be the most abundant in MA-BCa. Consistently, epithelial-mesenchymal transition-associated markers were also increased in MA-BCa. The disease enrichment analysis of the predict target genes revealed that diabetes mellitus was significantly affected disease in MA-BCa. Taken together, our data suggest that miRNA-based regulatory mechanism associated with deregulation of pathways and biological functions orchestrated by adipocytes-secreted factors might drive the BCa progression and metastasis in obese patients.

Role of MicroRNA Regulation in Obesity-Associated Breast Cancer: Nutritional Perspectives.

Breast cancer is the most common malignancy diagnosed in women, and the incidence of breast cancer is increasing every year. Obesity has been identified as one of the major risk factors for breast cancer progression. The mechanisms by which obesity contributes to breast cancer development is not yet understood; however, there are a few mechanisms counted as potential producers of breast cancer in obesity, including insulin resistance, chronic inflammation and inflammatory cytokines, adipokines, and sex hormones. Recent emerging evidence suggests that alterations in microRNA (miRNA) expressions are found in several diseases, including breast cancer and obesity; however, miRNA roles in obesity-linked breast cancer are beginning to unravel. miRNAs are thought to be potential noninvasive biomarkers for diagnosis and prognosis of cancer patients with comorbid conditions of obesity as well as therapeutic targets. Recent studies have evidenced that nutrients and other dietary factors protect against cancer and obesity through modulation of miRNA expressions. Herein, we summarize a comprehensive overview of up-to-date information related to miRNAs and their molecular targets involved in obesity-associated breast cancer. We also address the mechanisms by which dietary factors modulate miRNA expression and its protective roles in obesity-associated breast cancer. It is hoped that this review would provide new therapeutic strategies for the treatment of obesity-associated breast cancer to reduce the burden of breast cancer.

C-phycocyanin suppresses transforming growth factor-ß1-induced epithelial mesenchymal transition in human epithelial cells.

BACKGROUND: Epithelial mesenchymal transition (EMT) is a process through which epithelial cells undergo multiple biochemical changes, causing them to differentiate into a mesenchymal-cell phenotype. This process has been shown to contribute to the development of fibrotic diseases. C-phycocyanin (C-PC) is a phycobiliprotein extracted from Spirulina platensis. This study was done to investigate the effect of C-PC on transforming growth factor-ß1 (TGF-ß1)-induced EMT and an EMT associated proliferation in human epithelial cell lines. METHODS: Human adenocarcinoma cell line, A549 and breast cancer cell line, MCF-7 were treated with TGF-ß1, and EMT-related genes expression, cell proliferation and cell cycle arrest were examined. RESULTS: C-PC suppressed the EMT as assessed by reduced expression of vimentin, type-1-collagen and fibronectin, and increased E-cadherin expression in TGF-ß1 treated cells. Further, TGF-ß1 treatment induced cell cycle arrest in S and G2/M phase in A549 cells. However, TGF-ß1-mediated cell cycle arrest was significantly reversed by combined treatment with C-PC. CONCLUSIONS: The overall data suggested that C-PC suppresses TGF- ß1-induced EMT and warrants further in vivo studies for future evaluation of C-PC as a potential antifibrotic agent.