Simvastatin prevents BMP-2 driven cell migration and invasion by suppressing oncogenic DNMT1 expression in breast cancer cells.

Both epigenetic and genetic changes in the cancer genome act simultaneously to promote tumor development and metastasis. Aberrant DNA methylation, a prime epigenetic event, is often observed in various cancer types. The elevated DNA methyltransferase 1 (DNMT1) enzyme creates DNA hypermethylation at CpG islands to drive oncogenic potential. This study emphasized to decipher the molecular mechanism of endogenous regulation of DNMT1 expression for finding upstream signaling molecules. Cancer database analyses found an upregulated DNMT1 expression in most cancer types including breast cancer. Overexpression of DNMT1 showed an increased cell migration, invasion, and stemness potential whereas 5-azacytidine (DNMT1 inhibitor) and siRNA mediated knockdown of DNMT1 exhibited inhibition of such cancer activities in breast cancer MDA-MB-231 and MCF-7 cells. Infact, cancer database analyses further found a positive correlation of DNMT1 transcript with both cholesterol pathway regulatory genes and BMP signaling molecules. Experimental observations documented that the cholesterol-lowering drug, simvastatin decreased DNMT1 transcript as well as protein, whereas BMP-2 treatment increased DNMT1 expression in breast cancer cells. In addition, expression of various key cholesterol regulatory genes was found to be upregulated in response to BMP-2 treatment. Moreover, simvastatin inhibited BMP-2 induced DNMT1 expression in breast cancer cells. Thus, this study for the first time reveals that both BMP-2 signaling and cholesterol pathways could regulate endogenous DNMT1 expression in cancer cells.

Metformin prevents osteoblast-like potential and calcification in lung cancer A549 cells.

In spite of recent advances made in understanding its progression, cancer is still a leading cause of death across the nations. Molecular pathophysiology of these cancer cells largely differs depending on cancer types and even within the same tumor. Pathological mineralization/calcification is seen in various tissues including breast, prostate, and lung cancer. Osteoblast-like cells derived after trans-differentiation of mesenchymal cells usually drive calcium deposition in various tissues. This study aims to explore the presence of osteoblast-like potential in lung cancer cells and its prevention. ALP assay, ALP staining, nodule formation, RT-PCR, RT-qPCR, and western blot analysis experiments were carried out in lung cancer A549 cells to achieve said objective. Expressions of various osteoblast markers (e.g., ALP, OPN, RUNX2, and Osterix) along with osteoinducer genes (BMP-2 and BMP-4) were observed in A549 cells. Moreover, ALP activity and ability leading to nodule formation revealed the presence of osteoblast-like potential in lung cancer cells. Here, BMP-2 treatment increased expressions of osteoblast transcription factors such as RUNX2 and Osterix, enhanced ALP activity, and augmented calcification in this cell line. It was also observed that antidiabetic metformin inhibited BMP-2 mediated increase in osteoblast-like potential and calcification in these cancer cells. The current study noted that metformin blocked BMP-2 mediated increase in epithelial to mesenchymal transition (EMT) in A549 cells. The above findings for the first time unravel that A549 cells possess osteoblast-like potential which drives lung cancer calcification. Metformin might prevent BMP-2 induced osteoblast-like phenotype of the lung cancer cells with concomitant inhibition of EMT to inhibit lung cancer tissue calcification.

Metformin ameliorates BMP2 induced adipocyte-like property in breast cancer cells.

Neighboring adipocytes of tumor cells/cancer associated adipocytes supply many factors and fatty acids as fuel to cancer cells for inducing cancer progression and development. Epithelial breast cancer cells also differentiate into several cell types to meet various demands. This study reports that breast cancer cells exhibit inherent adipocyte-like property which is further enhanced in presence of BMP2. Antidiabetic metformin inhibits BMP2 induced adipocyte-like potential in breast cancer cells. Interestingly, breast cancer cells not only show lipid accumulation but also have ability to release lipid content. Thus, this study centers around the presence of the adipocyte cell-like property in breast cancer cells, the significance of BMP2 and metformin that may be explored in designing therapeutics against breast cancer.

Dysregulated cholesterol regulatory genes as a diagnostic biomarker for cancer.

BACKGROUND: A dysregulation of cholesterol homeostasis is often seen in various cancer cell types, and elevated cholesterol content and that of its metabolites appears to be crucial for cancer progression and metastasis. Cholesterol is a precursor of various steroid hormones and a key plasma membrane component especially in lipid-rafts, also modulating many intracellular signaling pathways. METHODS: To provide an insight of dysregulated cholesterol regulatory genes, their transcript levels were analyzed in different cancers and their influence was correlated with the overall survival of cancer patients using cancer database analysis. RESULTS: This analysis found a set of genes (e.g., ACAT1, RXRA, SOAT1 and SQLE) that were not only often dysregulated, but also had been associated with poorer overall survival in most cancer types. Quantitative reverse transcriptase-polymerase chain reaction analysis revealed elevated SQLE and SOAT1 transcript levels and downregulated expression of RXRA and ACAT1 genes in triple negative breast cancer tissues compared to adjacent control tissues, indicating that this dysregulated expression of the gene signature is a diagnostic marker for breast cancer. CONCLUSION: For the first time, the present study identified a gene signature associated with the dysregulation of cholesterol homeostasis in cancer cells that may not only be used as a diagnostic marker, but also comprise a promising drug target for the advancement of cancer therapy.

Omega-3 Fatty Acid Treatment Combined with Chemotherapy to Prevent Toxicity, Drug Resistance, and Metastasis in Cancer.

Despite advances in treatment, individuals diagnosed with cancer are often at risk of suffering from metastasis, tumor recurrence, therapy resistance, and off-target toxicities from conventional chemo-, radio-, and endocrine- therapies. Drugs with potent anticancer and antimetastatic activity but with milder side effects can be combined with conventional therapies to increase efficacy, reduce therapy resistance, and decrease toxicity. Substantial data from epidemiological, cell culture, animal, and clinical studies have established the anticancer potential of nontoxic omega-3 fatty acids. This paper highlights the beneficial effects of omega-3 fatty acid treatment when used in combination with conventional therapies to protect against metastasis, enhance therapeutic efficacy, and prevent the off-target toxicity caused by conventional therapies. These omega-3 fatty acids target therapy-induced central players, NF-κB and ROS, to prevent drug-associated metastasis, therapy resistance, and off-target toxicities.

Molecular insights into the interplay between adiposity, breast cancer and bone metastasis.

Cancer is a complex disease, with various pre-existing health ailments enhancing its pathology. In cancer, the extracellular environment contains various intrinsic physiological factors whose levels are altered with aging and pre-existing conditions. In obesity, the tumor microenvironment and metastases are enriched with factors that are both derived locally, and from other physiological compartments. Similarly, in obesity, the cancer cell environment both at the site of origin and at the secondary site i.e., metastatic niche, contains significantly more phenotypically-altered adipocytes than that of un-obese cancer patients. Indeed, obesity has been linked with cancer progression, metastasis, and therapy resistance. Adipocytes not only interact with tumor cells, but also with adjacent stromal cells at primary and metastatic sites. This review emphasizes the importance of bidirectional interactions between adipocytes and breast tumor cells in breast cancer progression and its bone metastases. This paper not only chronicles the role of various adipocyte-derived factors in tumor growth, but also describes the significance of adipocyte-derived bone metastatic factors in the development of bone metastasis of breast cancer. It provides a molecular view of the interplay between the adipocytes and tumor cells involved in breast cancer bone metastasis. However, more research is needed to determine if targeting cancer-associated adipocytes holds promise as a potential therapeutic approach for breast cancer bone metastasis treatment. Interplay between adipocytes and breast cancer cells at primary cancer site and metastatic bone microenvironment. AMSC Adipose-derived mesenchymal stem cell, CAA Cancer associated adipocytes, CAF Cancer associated fibroblast, BMSC Bone marrow derived mesenchymal stem cell, BMA Bone marrow adipocyte.

Discordance between Fluorescence In Situ Hybridization and Immunohistochemistry Analysis of Anaplastic Lymphoma Kinase Rearrangement in Indian Patients with Non-Small Cell Lung Cancer.

Aims This study aims to evaluate the incidence of anaplastic lymphoma kinase (ALK) mutation in nonsmall cell lung cancer (NSCLC) incorporating fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) methods and to look for any discordance. Methods We evaluated 101 samples obtained from an enriched cohort of NSCLCs patients from the Army Hospital Research and Referral, New Delhi, India, between November 2016 and November 2018. IHC was performed using the highly-sensitive D5F3 rabbit monoclonal primary antibody. FISH was performed with dual-color, break-apart probe (ZytoLight SPEC) on formalin-fixed, and paraffin-embedded tissue. Discordance between IHC and FISH for ALK rearrangements was evaluated. Pearson correlation coefficient ( r ) was performed to identify any association of ALK presence (by IHC and FISH) with smoking brain metastasis, programmed death-ligand (PD-L1) expression, pleural effusion, and histopathological subtype. Results A total of 7.92% (8/101) cases tested by IHC and 9.9% (10/101) cases tested by FISH were positive for ALK rearrangement. Of 93 ALK IHC-negative cases, 4 were ALK FISH-positive, whereas of 91 ALK FISH-negative cases, 4 were ALK IHC-positive cases. The correlation analysis demonstrated no or very weak correlation in ALK mutations by IHC or FISH with smoking, brain metastasis, PD-L1 expression, pleural effusion, and histopathological examination, except a weak positive correlation ( r = 0.33) observed between brain metastasis and ALK rearrangement identified by FISH. Conclusions Our study demonstrated a somewhat similar incidence of ALK FISH-positive cases and ALK IHC-positive cases, though the incidence was numerically higher for ALK-FISH method.

Correlation of programmed death-ligand 1 expression with gene expression and clinicopathological parameters in Indian patients with non-small cell lung cancer.

OBJECTIVES: The aim of this study is to evaluate the incidence of programmed cell death-ligand 1 (PD-L1) expression in non-small cell lung cancer (NSCLC) cases and its correlation with gene mutation and clinicopathological parameters. METHODS: Samples from NSCLCs patients were studied for PD-L1 expression through immunohistochemistry (IHC) using Rabbit anti-human PDL-1/CD274 Monoclonal Antibody. Genetic mutations were studied using IHC/fluorescence in situ hybridization (FISH) methods (for anaplastic lymphoma kinase [ALK]) or polymerase chain reaction/gene sequencing analysis (for epidermal growth factor receptor [EGFR]). Pearson's correlation coefficient (r) was used for correlation analysis. PD-L1 expression was analyzed for association with clinicopathological features. RESULTS: Of the 101 NSCLC cases, PD-L1 expression was observed in 33.66% (34/101) cases; tumor proportion score of <50%: 67.65% (23/34) and ≥50%: 32.35% (11/34) cases. PD-L1 positivity was seen in; males: 35.5%, females: 28%, smokers: 37.7%, cases with brain metastasis: 20%, cases with pleural effusion: 20.8%, and histopathological evaluation (well-differentiated: 21.42%, moderately-differentiated: 13.79%, poorly-differentiated: 36.11%, and adenosquamous disease: 40.9%). Genetic mutation studies revealed PD-L1 positivity in 18.1% cases with EGFR mutation, 50% of ALK-IHC positive cases, and 33.3% ALK-FISH positive cases. No or very weak correlation (r < 0.3) in PD-L1 expression with gene mutations or clinicopathological parameters was observed. CONCLUSIONS: The study demonstrated PD-L1 expression in ~ 1/3rd cases of NSCLC patients. No or very weak correlation was observed for PD-L1 expression with genetic mutations and other parameters studied. The presence of gene mutations in PD-L1 expressed samples suggests further investigation on PD-L1 inhibitors in such patients for decisive treatments.