Deregulated miRNA Expression in Triple-Negative Breast Cancer of Ancestral Genomic-Characterized Latina Patients.

Among patients with triple-negative breast cancer (TNBC), several studies have suggested that deregulated microRNA (miRNA) expression may be associated with a more aggressive phenotype. Although tumor molecular signatures may be race- and/or ethnicity-specific, there is limited information on the molecular profiles in women with TNBC of Hispanic and Latin American ancestry. We simultaneously profiled TNBC biopsies for the genome-wide copy number and miRNA global expression from 28 Latina women and identified a panel of 28 miRNAs associated with copy number alterations (CNAs). Four selected miRNAs (miR-141-3p, miR-150-5p, miR-182-5p, and miR-661) were validated in a subset of tumor and adjacent non-tumor tissue samples, with miR-182-5p being the most discriminatory among tissue groups (AUC value > 0.8). MiR-141-3p up-regulation was associated with increased cancer recurrence; miR-661 down-regulation with larger tumor size; and down-regulation of miR-150-5p with larger tumor size, high p53 expression, increased cancer recurrence, presence of distant metastasis, and deceased status. This study reinforces the importance of integration analysis of CNAs and miRNAs in TNBC, allowing for the identification of interactions among molecular mechanisms. Additionally, this study emphasizes the significance of considering the patients ancestral background when examining TNBC, as it can influence the relationship between intrinsic tumor molecular characteristics and clinical manifestations of the disease.

A panel of miRNAs as prognostic markers for African-American patients with triple negative breast cancer.

BACKGROUND: To investigate the global expression profile of miRNAs, their impact on cellular signaling pathways, and their association with poor prognostic parameters in African-American (AA) patients with triple negative breast cancer (TNBC). METHODS: Twenty-five samples of AA TNBC patients were profiled for global miRNA expression and stratified considering three clinical-pathological parameters: tumor size, lymph node (LN), and recurrence (REC) status. Differential miRNA expression analysis was performed for each parameter, and their discriminatory power was determined by Receiver Operating Characteristic (ROC) curve analysis. KMplotter was assessed to determine the association of the miRNAs with survival, and functional enrichment analysis to determine the main affected pathways and miRNA/mRNA target interactions. RESULTS: A panel of eight, 23 and 27 miRNAs were associated with tumor size, LN, and REC status, respectively. Combined ROC analysis of two (miR-2117, and miR-378c), seven (let-7f-5p, miR-1255b-5p, miR-1268b, miR-200c-3p, miR-520d, miR-527, and miR-518a-5p), and three (miR-1200, miR-1249-3p, and miR-1271-3p) miRNAs showed a robust discriminatory power based on tumor size (AUC = 0.917), LN (AUC = 0.945) and REC (AUC = 0.981) status, respectively. Enrichment pathway analysis revealed their involvement in proteoglycans and glycan and cancer-associated pathways. Eight miRNAs with deregulated expressions in patients with large tumor size, positive LN metastasis, and recurrence were significantly associated with lower survival rates. Finally, the construction of miRNA/mRNA networks based in experimentally validated mRNA targets, revealed nodes of critical cancer genes, such as AKT1, BCL2, CDKN1A, EZR and PTEN. CONCLUSIONS: Altogether, our data indicate that miRNA deregulated expression is a relevant biological factor that can be associated with the poor prognosis in TNBC of AA patients, by conferring to their TNBC cells aggressive phenotypes that are reflected in the clinical characteristics evaluated in this study.

Design, synthesis and cytotoxicity studies of dithiocarbamate ester derivatives of emetine in prostate cancer cell lines.

A small library of emetine dithiocarbamate ester derivatives were synthesized in 25-86% yield via derivatization of the N2'- position of emetine. Anticancer evaluation of these compounds in androgen receptor positive LNCaP and androgen receptor negative PC3 and DU145 prostate cancer cell lines revealed time dependent and dose-dependent cytotoxicity. With the exception of compound 4c, all the dithiocarbamate ester analogs in this study showed appreciable potency in all the prostate cancer cell lines (regardless of whether it is androgen receptor positive or negative) with a cytotoxicity IC50 value ranging from 1.312 ± 0.032 µM to 5.201 ± 0.125 µM by day 7 of treatment. Compared to the sodium dithiocarbamate salt 1, all the dithiocarbamate ester analogs (2 and 4a-4 g) displayed lower cytotoxicity than compound 1 (PC3, IC50 = 0.087 ± 0.005 µM; DU145, IC50 = 0.079 ± 0.003 µM and LNCaP, IC50 = 0.079 ± 0.003 µM) on day 7 of treatment. Consequently, it appears that S-alkylation of compound 1 leads to a more stable dithiocarbamate ester derivative that resulted in lower anticancer activity in the prostate cancer cell lines.

Advances, limitations and perspectives in the use of celecoxib-loaded nanocarriers in therapeutics of cancer.

Cancer is highlighted as a major global health challenge in the XXI century. The cyclooxygenase-2 (COX-2) enzyme rises as a widespread tumor progression marker. Celecoxib (CXB) is a selective COX-2 inhibitor used in adjuvant cancer therapy, but high concentrations are required in humans. In this sense, the development of nanocarriers has been proposed once they can improve the biopharmaceutical, pharmacokinetic and pharmacological properties of drugs. In this context, this article reviews the progress in the development of CXB-loaded nanocarriers over the past decade and their prospects. Recent advances in the field of CXB-loaded nanocarriers demonstrate the use of complex formulations and the increasing importance of in vivo studies. The types of CXB-loaded nanocarriers that have been developed are heterogeneous and based on polymers and lipids together or separately. It was found that the work on CXB-loaded nanocarriers is carried out using established techniques and raw materials, such as poly (lactic-co-glicolic acid), cholesterol, phospholipids and poly(ethyleneglycol). The main improvements that have been achieved are the use of cell surface ligands, the simultaneous delivery of different synergistic agents, and the presence of materials that can provide imaging properties and other advanced features. The combination of CXB with other anti-inflammatory drugs and/or apoptosis inducers appears to hold effective pharmacological promise. The greatest advance to date from a clinical perspective is the ability of CXB to enhance the cytotoxic effects of established chemotherapeutic agents.

Dihydromyricetin Protects Against Salsolinol-Induced Toxicity in Dopaminergic Cell Line: Implication for Parkinson's Disease.

Parkinson's disease (PD) is a progressive neurodegenerative disease associated with loss of dopaminergic neurons in the substantia nigra pars compacta. Although aging is the primary cause, environmental and genetic factors have also been implicated in its etiology. In fact, the sporadic nature of PD (i.e., unknown etiology) renders the uncovering of the exact pathogenic mechanism(s) or development of effective pharmacotherapies challenging. In search of novel neuroprotectants, we showed that butyrate (BUT), a short-chain fatty acid, protects against salsolinol (SALS)-induced toxicity in human neuroblastoma-derived SH-SY5Y cells, which are considered an in-vitro model of PD. Dihydromyricetin (DHM), a flavonoid derived from Asian medicinal plant, has also shown effectiveness against oxidative damage and neuroinflammation, hallmarks of neurodegenerative diseases. Here we show that pretreatment of SH-SY5Y cells with DHM concentration-dependently prevented SALS-induced toxicity and that a combination of DHM and BUT resulted in a synergistic protection. The effects of both DHM and BUT in turn could be completely blocked by flumazenil (FLU), a GABAA antagonist acting at benzodiazepine receptor site, and by bicuculline (BIC), a GABAA antagonist acting at orthosteric site. Beta-hydroxybutyrate (BHB), a free fatty acid 3 (FA3) receptor antagonist, also fully blocked the protective effect of DHM. BHB was shown previously to only partially block the protective effect of BUT. Thus, there are some overlaps and some distinct differences in protective mechanisms of DHM and BUT against SALS-induced toxicity. It is suggested that a combination of DHM and BUT may have therapeutic potential in PD. However, further in-vivo verifications are necessary.

Cyclin A2 and Ki-67 proliferation markers could be used to identify tumors with poor prognosis in African American women with breast cancer.

Background: Diagnosed invasive breast carcinomas in African American patients are more aggressive compared with those in Caucasian patients and diagnosed at later stages of the disease with higher grade tumors. Despite advances in breast cancer systemic treatment, new prognostic and predictive biomarkers are still needed. Therefore, potential biomarkers were chosen to correlate with different subtypes, recurrence, and survival of invasive breast cancer in a cohort of African American women. Methods: Eight protein biomarkers (ER, PR, HER2, Cyclin A2, Cytokeratin 5, Vimentin, Bcl2, and Ki-67) were evaluated using tissue microarrays (TMAs) and immunohistochemistry (IHC). The IHC results from TMAs were analyzed by both supervised and unsupervised clustering methods. The predictive clusters for the supervised and unsupervised methods were compared for agreement with the empirical classification. Kappa values were used to determine the overall percent correct clusters and agreement between specific clusters. Chi-square statistics was used to examine the association between hierarchical and multinomial logistic clustering methods. Results: Five subtypes of breast tumors with distinct protein expression patterns were identified among the studied 166 breast tumors. Luminal B tumors have been distinguished from luminal A tumors by staining for cell cycle proteins Cyclin A2 and Ki-67, which promote cell proliferation. Forty-nine percent were stained positive for Cyclin A2, 39.2% positive for Ki-67, and 37% positive for both Cyclin A2 and Ki-67. The age of patients did not show any significant effect whether five (p-value= 0.576) or eight (p-value= 0.605) biomarkers were used, which indicating that age did not have any influence on the classification of the subtypes. Ninety percent of the thirty triple negative tumors were positive for Cyclin A2 or Ki-67 or both. Six-year overall survival was better for luminal A tumors (76%) than luminal B tumors (71%). Likewise, six-year relapse-free survival was better for luminal A tumors (76%) than luminal B tumors (29%). Conclusion: Discovery of molecular markers such as Cyclin A2 and Ki-67, and subtypes that are most prevalent in African Americans could lead to a better understanding of the factors contributing to higher morbidity and mortality in this group and to aid in decision-making to offer earlier treatment.

Synthesis and cytotoxic activities of some 2-arylnaphtho[2,3-d]oxazole-4,9-dione derivatives on androgen-dependent (LNCaP) and androgen-independent (PC3) human prostate cancer cell lines.

The synthesis of five 2-arylnaphtho[2,3-d]oxazole-4,9-dione derivatives was accomplished by refluxing 2-amino-3-bromo-1,4-naphthoquinone with appropriate benzoyl chloride analogs at elevated temperatures. In vitro anticancer evaluation of these compounds was performed on androgen-dependent, LNCaP, and androgen-independent, PC3, human prostate cancer cell lines. In general, these compounds displayed slightly stronger cytotoxicity on the androgen-dependent LNCaP than on the androgen-independent PC3 prostate cancer cell lines. The meta-substituted 2-(3-Chloro-phenyl)-naphtho[2,3-d]oxazole-4,9-dione (10) appear to display the best cytotoxicity on both cell lines with an IC(50) of 0.03 µM on LNCaP and 0.08 µM on PC3 after 5 days of exposure.

Inverse Correlation of KISS1 and KISS1R Expression in Triple-negative Breast Carcinomas from African American Women.

BACKGROUND/AIM: The kisspeptin 1 (KISS1) gene encodes a precursor polypeptide which after proteolysis forms the kisspeptin-10 (KISS1) protein. KISS1, retains maximum physiological activity when it binds to its receptor (KISS1R), allowing KISS1 to effectively function as a suppressor of metastasis in melanomas and other types of cancer. The goal of this study was to evaluate the expression of KISS1 and KISS1R in breast carcinomas from African American (AA) women and correlate their association with clinicopathological features, including breast cancer subtypes, and outcomes. MATERIALS AND METHODS: Tissue microarrays were constructed from formalin-fixed, paraffin-embedded surgical blocks from 216 AA patients. KISS1 and KISS1R expression was assessed using immunohistochemistry. Univariate analysis was used to determine the association between the expression of KISS1 and KISS1R, and clinicopathological characteristics. Pearson correlation was also determined between immunohistochemical H-scores, tumor size, and the number of positive lymph nodes. Kaplan-Meier estimates of overall and disease-free survival were plotted, and log-rank tests were performed to compare estimates among groups. RESULTS: KISS1 protein expression was found to be higher in receptor-negative and triple-negative breast cancer (TNBC) compared to other subtypes (p<0.001). However, KISS1R expression was higher in non-TNBC tumors compared to other subtypes (p<0.001). Higher KISS1R expression was marginally negatively correlated with tumor size (p=0.077), and positively correlated with lymph-node positivity (p=0.056), and disease-free survival (p=0.092). CONCLUSION: Our study showed a significant inverse correlation between KISS1 and KISS1R in TNBC. This investigation implicates a role for KISS1 and KISS1R in the pathogenesis of TNBCs in AA women.

Sodium Butyrate Protects Against Ethanol-Induced Toxicity in SH-SY5Y Cell Line.

Alcohol use disorder (AUD), brought about by excessive alcohol use, is associated with damages to several organs including the brain. Chronic excessive use of alcohol can compromise intestinal integrity, leading to changes in gut microbiota (GM) composition known as dysbiosis. Dysbiosis, by disruption of the gut-brain axis (GBA), further exacerbates the deleterious effects of alcohol. One of the fermentation by-products of GM is butyrate (BUT), a short-chain fatty acid (SCFA) that plays an important role in maintaining homeostasis of the GBA. Alcohol metabolism results in formation of acetaldehyde, a highly reactive compound that reacts with dopamine in the brain to form toxic adducts such as salsolinol. Recent studies indicate potential neuro-protective effects of BUT against various toxicants including salsolinol. Here, we sought to investigate whether BUT can also protect against alcohol toxicity. Pretreatment of neuroblastoma-derived SH-SY5Y cells with 500 mM ethanol (ETOH) for 24 h resulted in approximately 40% reduction in cell viability, which was totally blocked by 10 µM of either BUT or AR 420,626 (AR), a selective fatty acid 3 receptor (FA3R) agonist. The neuro-protective effects of both BUT and AR were significantly (80%) attenuated by beta-hydroxy butyrate (BHB), a selective FA3R antagonist. Interestingly, combination of BUT and AR resulted in synergistic protection against ETOH, which was totally blocked by BHB. These findings suggest potential utility of butyrate and/or FA3R agonists against ETOH-induced toxicity.

Nicotine and the nicotinic cholinergic system in COVID-19.

There is an urgent need to address the devastating pandemic, COVID-19, caused by SARS-CoV-2. The efforts to understand the details of this disease in hope of providing effective treatments are commendable. It is clear now that the virus can cause far more damage in patients with comorbid conditions-particularly in those with respiratory, cardiovascular, or immune-compromised system-than in patients without such comorbidities. Drug use can further exacerbate the condition. In this regard, the ill effects of smoking are amply documented, and no doubt can be a confounding factor in COVID-19 progression. Although conflicting hypotheses on the potential role of nicotine in COVID-19 pathology have recently been offered, we believe that nicotine itself, through its interaction with the nicotinic cholinergic system, as well as ACE2, may not only be of use in a variety of neuropsychiatric and neurodegenerative diseases, but may also be of potential use in COVID-19. Thus, on one hand, while we strongly support smoking cessation as a means of harm reduction associated with COVID-19, on the other hand, we support a potential therapeutic role for nicotine, nicotinic agonists, or positive allosteric modulators of nicotinic cholinergic receptors in COVID-19, owing to their varied effects including mood regulation, anti-inflammatory, and purported interference with SARS-CoV-2 entry and/or replication.

Combinatorial Cytotoxic Effects of 2,3-Dichloro-5,8-dimethoxy-1,4-naphthoquinone and 4-hydroxytamoxifen in Triple-negative Breast Cancer Cell Lines.

BACKGROUND/AIM: Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer (BC) and lacks targeted therapy and alternate therapeutic combinations. There is a necessity to increase disease-free survival in patients particularly within the first 5 years of diagnosis. 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (Z285), a novel 1,4 naphthoquinone analog, has been shown to have cytotoxic activity in BC cell lines and in combination with 4-hydroxytamoxifen (4-OHT). A known metabolite of tamoxifen, was postulated to decrease cell proliferation. Thus, this study investigates the use of Z285 and 4-OHT alone or in combination as a novel therapeutic alternative for TNBC. MATERIALS AND METHODS: Cell proliferation assays were performed on MDA-MB-231, Hs578T, MCF7 and HCC1806 cell lines at varying time points with Z285 and 4-OHT alone and in combination. Furthermore, ROS activity was measured to determine the changes in oxidative stress caused by both drugs. RESULTS: The results showed dose- and time-dependent decreases in proliferation for all cell lines when treated with Z285, 4-OHT and their combination. Combinatorial analysis performed at 72 h using Synergyfinder® showed additive effects in MCF7, HCC1806 and Hs578T and an antagonistic response in MDA-MB-231. Z285 caused a significant increase in ROS production in three cell lines after 8 h, but HCC1806 showed no change in effect. CONCLUSION: These promising results suggest the independent ability of each compound as a stand-alone chemotherapeutic agent, or in combinatorial therapy for the treatment of TNBC.

Butyrate Protects Against Salsolinol-Induced Toxicity in SH-SY5Y Cells: Implication for Parkinson's Disease.

Parkinson's disease (PD), a progressive neurodegenerative disorder, is associated with the destruction of dopamine neurons in the substantia nigra (SN) and the formation of Lewy bodies in basal ganglia. Risk factors for PD include aging, as well as environmental and genetic factors. Recent converging reports suggest a role for the gut microbiome and epigenetic factors in the onset and/or progression of PD. Of particular relevance and potential therapeutic targets in this regard are histone deacetylases (HDACs), enzymes that are involved in chromatin remodeling. Butyrate, a short-chain fatty acid (FA) produced in the gut and presumably acting via several G protein-coupled receptors (GPCRs) including FA3 receptors (FA3Rs), is a well-known HDAC inhibitor that plays an important role in maintaining homeostasis of the gut-brain axis. Recently, its significance in regulation of some critical brain functions and usefulness in neurodegenerative diseases such as PD has been suggested. In this study we sought to determine whether butyrate may have protective effects against salsolionl (SALS)-induced toxicity in SH-SY5Y cells. SALS, an endogenous product of aldehyde and dopamine condensation, may be selectively toxic to dopaminergic neurons. SH-SY5Y cells, derived from human neuroblastoma cells, are used as a model of these neurons. Exposure of SH-SY5Y cells for 24 h to 400 µM SALS resulted in approximately 60% cell death, which was concentration-dependently prevented by butyrate. The effects of butyrate in turn were significantly attenuated by beta-hydroxy butyrate (BHB), a selective FA3R antagonist. Moreover, a selective FA3R agonist (AR 420626) also provided protective effects against SALS, which was totally blocked by BHB. These findings provide further support that butyrate or an agonist of FA3R may be of therapeutic potential in PD.

The Association Between the Genetic VDR SNP c.907+75C>T and Prostate Cancer Risk Is Modified by Tanning Potential.

BACKGROUND: Prostate cancer (PCa) is a multifactorial disease involving complex interactions between genetic and physiological/environmental factors. Vitamin D receptor (VDR) plays a role in numerous cellular pathways and it has been suggested that VDR genetic variants influence individual susceptibility to PCa. MATERIALS AND METHODS: Logistic regression analysis was used to assess the association of six VDR single nucleotide polymorphisms (SNPs) and factors such as tanning potential and UV sunlight exposure with PCa risk. RESULTS: Marginal significant interactions were found, with a 2-fold increase risk of PCa between SNP 1 (c.278-69G>A) and sunlight UV exposure [odds ratio (OR)=2.02, 95% confidence intervaI (CI)=1.036-4.36; p=0.05]; and a 4-fold increase risk of PCa between SNP 4 (c.907+75C>T) and tanning potential (OR=4.40, 95% CI=0.89-29.12; p=0.0591). In contrast, SNP 5 (rs731236, TaqI) and tanning potential interaction had a protective effect by reducing the risk of PCa by 55% (ß=-0.804; OR=0.448, 95% CI=0.197-9.42; p=0.0427). SNPs 2 (rs61614328) and 6 (rs533037428) did not show any association with PCa even in the presence of UV sunlight exposure. CONCLUSION: The protective effect of SNP 4 from PCa is lost and modified by tanning potential in African Americans. This finding needs to be verified by larger studies in different ethnic populations.

Biological evaluation of 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone as an anti-breast cancer agent.

BACKGROUND: Breast cancer is the most frequent cancer and the second leading cause of cancer deaths in women today. A number of 1,4-naphthoquinone derivatives have been found to possess significant pharmacological effects associated with marked antimicrobial and antitumor activities. In the present study, the in vitro effect of 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (DCDMNQ) was evaluated on estrogen-positive MCF-7 and estrogen-negative MDA-MB-436 and Hs-578T human breast cancer cell lines. Moreover, the in vitro activity of this compound on cell cycle regulation and apoptosis were evaluated. MATERIALS AND METHODS: Established methods of cell viability, cell cycle, Western blot and apoptosis were used. RESULTS: The effect of DCDMNQ on MCF-7, MDA-MB-436 and Hs-578T cells revealed significant antitumor activities with IC(50)s, of 0.6 +/- 0.02, 1.4 +/- 0.25 and 3.1 +/- 0.4 microM respectively. Cell cycle analysis showed that DCDMNQ inhibited progression through the cell cycle in MCF-7 and MDA-MB-436 cell lines in a time-dependent manner. DCDMNQ arrested cells in the S-phase of the cell cycle with the greatest proportion of cells in the S-phase by day 5. This cell-cycle arrest was corroborated by inhibition of topoisomerase I induced by DCDMNQ. These findings were further validated using Western blot analysis of retinoblastoma protein time-dependent phosphorylation. Furthermore, DCDMNQ induced apoptosis in both estrogen-positive and -negative cell lines in a time-dependent manner. However, the highest percentages of apoptotic cells were observed in the MDA-MB-436 cell line. CONCLUSION: Although the mechanism of action of DCDMNQ has not been completely elucidated, it appears that this compound can inhibit topoisomerase I in a concentration-dependent manner. These promising results to explore novel naphthoquinone analogues as potential breast cancer agents. This study suggests that DCDMNQ may have an impact on treatment of estrogen-positive and -negative breast cancer while protecting the bone marrow.

Novel targets for parkinsonism-depression comorbidity.

With the aging population growing and the incidence of neurodegenerative diseases on the rise, the researchers in the field are yet more urgently challenged to slow and/or reverse the devastating consequences of such progression. The challenge is further enforced by psychiatric co-morbid conditions, particularly the feeling of despair in these population. Fortunately, as our understanding of the neurobiological substrates of maladies affecting the central nervous system increases, more therapeutic options are also presented. In this short review while providing evidence of shared biological substrates between Parkinson's disease and depression, novel therapeutic targets and drugs are suggested. The emphasis will be on neuroplasticity underscored by roles of neurotrophic and inflammatory factors. Examples of few therapeutic drugs as well as future directions are also touched upon.

The Association of a Novel Identified VDR SNP With Prostate Cancer in African American Men.

BACKGROUND/AIM: Vitamin D receptor (VDR) is present in numerous cellular pathways and it has been suggested that VDR genetic variants influence individual susceptibility to prostate cancer. Also, analyses of single nucleotide polymorphisms (SNPs) in VDR revealed ethnicity-associated polymorphisms. The aim of this study was to identify VDR SNPs in African American men with and without prostate cancer. MATERIALS AND METHODS: The entire VDR gene was screened for germline mutations in a case-control study by denaturing high performance liquid chromatography and DNA sequencing. Logistic regression was used to estimate the association of SNPs, age, family history, and Gleason score with prostate cancer risk. RESULTS: Six SNPs in the non-coding regions, and one SNP in the coding region, were detected. SNP 1 (c.278-69G>A) and SNP 4 (c.907+75C>T) have not been previously reported. SNP 4 had a significant protective effect (ß=-0.6, p<0.05); whereas, SNP 7 (rs7975232) showed an increase association with prostate cancer risk and high Gleason score (ß=0.32, p<0.05). SNP 4, SNP 7 and age were better predictors of prostate cancer risk than family history with a high degree of sensitivity (74.7%) and specificity (92.4%). CONCLUSION: SNP 4 and SNP 7 could be promising markers for prediction of reduced or increased prostate cancer risk, respectively.

Kernel-Based Microfluidic Constriction Assay for Tumor Sample Identification.

A high-throughput multiconstriction microfluidic channels device can distinguish human breast cancer cell lines (MDA-MB-231, HCC-1806, MCF-7) from immortalized breast cells (MCF-10A) with a confidence level of ∼81-85% at a rate of 50-70 cells/min based on velocity increment differences through multiconstriction channels aligned in series. The results are likely related to the deformability differences between nonmalignant and malignant breast cells. The data were analyzed by the methods/algorithms of Ridge, nonnegative garrote on kernel machine (NGK), and Lasso using high-dimensional variables, including the cell sizes, velocities, and velocity increments. In kernel learning based methods, the prediction values of 10-fold cross-validations are used to represent the difference between two groups of data, where a value of 100% indicates the two groups are completely distinct and identifiable. The prediction value is used to represent the difference between two groups using the established algorithm classifier from high-dimensional variables. These methods were applied to heterogeneous cell populations prepared using primary tumor and adjacent normal tissue obtained from two patients. Primary breast cancer cells were distinguished from patient-matched adjacent normal cells with a prediction ratio of 70.07%-75.96% by the NGK method. Thus, this high-throughput multiconstriction microfluidic device together with the kernel learning method can be used to perturb and analyze the biomechanical status of cells obtained from small primary tumor biopsy samples. The resultant biomechanical velocity signatures identify malignancy and provide a new marker for evaluation in risk assessment.

Cytotoxicity of 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone in androgen-dependent and -independent prostate cancer cell lines.

BACKGROUND: Prostate cancer ranks third worldwide in cancer incidence and sixth in cancer mortality among men. A number of 1,4-naphthoquinone derivatives have been found to possess significant pharmacological effects associated with marked antimicrobial and antitumor activities. In the present study the in vitro effect of 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (DCDMNQ) was evaluated on androgen-dependent (LNCaP, CWR-22) and androgen-independent (PC-3. DU-145) human prostate cancer cell lines, and/or a normal bone marrow cell line (HS-5). Moreover, the in vitro activity of this compound on cell cycle regulation and apoptosis was evaluated. MATERIALS AND METHODS: Established methods of cell viability, cell cycle, Western blot and apoptosis were used. RESULTS: The effect of DCDMNQ on LNCaP, CWR-22, PC-3, DU-145 and HS-5 cells revealed significant anti-tumor activities with IC50s, of 1, 3. 1.5, 3 and 10 microM respectively. Cell cycle analysis showed that DCDMNQ inhibited progression through the cell cycle in PC-3 and DU-145 cell lines in a time-dependent manner. The result for the CWR-22 cell line showed that DCDMNQ arrested cells in the G -phase of the cell cycle with the greatest proportion of cells in the G1-phase by day 5; however, the LNCaP cell line was inconsistent. The compound showed no effect on the cell cycle progression in the bone marrow HS-5 cell line. These findings were further validated using Western blot analysis. Furthermore, DCDMNQ induced apoptosis in the androgen-independent cells, preferentially over that of the androgen-dependent cell lines, in a time-dependent manner. CONCLUSION: Although the mechanism of action of this compound has not been completely elucidated, the effect on the cell cycle and the induction of apoptosis in different prostate cancer cell lines prompted us to carry out a more in-depth preclinical evaluation of it. This study suggests that DCDMNQ may have an impact on treatment of prostate cancer while protecting the bone marrow.

Antiapoptotic effects of nicotine in its protection against salsolinol-induced cytotoxicity.

Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline), a metabolite of dopamine, may act as an endogenous neurotoxin and contribute to the etiology of Parkinson's disease (PD). The inverse relationship between smoking and PD prompted our previous investigation and the report of protective effects of nicotine against salsolinol-induced toxicity in cultured SH-SY5Y cells (Copeland et al., Neurotox. Res. 8:289, 2005). These cells, derived from human neuroblastoma cells, express dopaminergic activity and are used as a model of nigral dopaminergic cells, the major site of pathology in PD. The purpose of the current study was to investigate whether apoptotic or antiapoptotic mechanisms were responsible for the observed effects of salsolinol and nicotine, respectively. Moreover, it was of interest to determine whether the actions of nicotine are mediated through nicotinic receptors. SH-SY5Y cells were exposed to 0.4 or 0.7 mM salsolinol with and without pretreatment in combination of 0.1 mM nicotine and 0.1 mM mecamylamine and were exposed for 24 and 48 h. Various parameters including cell cycle perturbations (reflected in propidium iodide DNA staining); cell cycle regulator retinoblastoma protein (reflected in the Western blot), apoptosis (reflected in annexin V/propidium iodide staining followed by flow cytometry) were analyzed. Salsolinol caused an arrest of the cells in G1-phase of cell cycle and an increase in apoptotic indices, whereas pretreatment with nicotine attenuated or completely blocked the effects of salsolinol. Nicotine effects in turn, were totally blocked by mecamylamine (0.1 mM). The results suggest that apoptosis is a major mechanism for salsolinol-induced toxicity and that antiapoptotic effects of nicotine, mediated by nicotinic receptors, may play a primary role in its neuroprotective effects. Hence, nicotinic agonists in combination with other antiapoptotic agents may be of substantial benefit in at least a subpopulation of Parkinson patients.