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The acquisition of resistance and ultimately disease relapse after initial response to chemotherapy put obstacles in the way of cancer therapy. Epithelial-mesenchymal transition (EMT) is a biologic process that epithelial cells alter to mesenchymal cells and acquire fibroblast-like properties. EMT plays a significant role in cancer metastasis, motility, and survival. Recently, emerging evidence suggested that EMT pathways are very important in making drug-resistant involved in cancer. Natural products are gradually emerging as a valuable source of safe and effective anticancer compounds. Natural products could interfere with the different processes implicated in cancer drug resistance by reversing the EMT process. In this review, we illustrate the molecular mechanisms of EMT in the emergence of cancer metastasis. We then present the role of natural compounds in the suppression of EMT pathways in different cancers to overcome cancer cell drug resistance and improve tumor chemotherapy. HighlightsDrug-resistance is one of the obstacles to cancer treatment.EMT signaling pathways have been correlated to tumor invasion, metastasis, and drug-resistance.Various studies on the relationship between EMT and resistance to chemotherapy agents were reviewed.Different anticancer natural products with EMT inhibitory properties and drug resistance reversal effects were compared.

One of the important barriers in the treatment of breast cancer is the development of tamoxifen resistance. Different mechanisms underlying tamoxifen resistance were identified. In this thesis, we aimed to assess the effect of tamoxifen resistance induction on ABCG2 gene/protein expression level and function in the parent MCF-7 breast cancer cell line and its tamoxifen-resistant (MCF-7/TAMR) cell line. The ABCG2 mRNA and protein expression were compared in MCF-7 and its tamoxifen-resistant derivative MCF-7/TAMR cells using Real-time PCR and western blot methods, respectively. For investigating the effect of tamoxifen-induced resistance on cross-resistance to other chemotherapy drugs such as mitoxantrone (as a well-known ABCG2 substrate), an MTT assay was used. Flow cytometry was applied to compare ABCG2 pump function between two cell lines using mitoxantrone accumulation assay. ABCG2 mRNA expression was also analyzed in tamoxifen-sensitive (TAM-S) (N=9) and tamoxifen-resistant (TAM-R) (N=9) breast tumor tissues. Our results indicated that the levels of ABCG2 mRNA, protein, and activity were significantly higher in MCF-7/TAMR cells compared to tamoxifen sensitive cell line and mitoxantrone was less toxic in the resistant cell line. Data further discovered that tamoxifen-resistant cells with high ABCG2 activation had a poor response when given rescue mitoxantrone chemotherapy. ABCG2 was also upregulated in tissue samples obtained from tamoxifen-resistant ER+ breast cancer patients compared to tamoxifen-sensitive patients. Increased expression of the ABCG2 mRNA and protein is a phenomenon that occurs after the emergence of resistance to tamoxifen and can cause cross-resistance to mitoxantrone in MCF-7 breast cancer cells.

Background: The development of multidrug resistance (MDR) is a major barrier to achieving effective chemotherapy in cancer. Studies have shown that epithelial ovarian cancer initially responds to platinum-based therapy, however, the recurrent type is often resistant to treatment and is associated with high mortality. Fucoxanthin, a natural component found in marine algae, possesses various pharmacologic properties. This study evaluated the cytotoxicity and resistance reversal activity of fucoxanthin on multidrug resistance-associated protein 2 (MRP2)-overexpressing, cisplatin-resistant ovarian cancer cells (A2780RCIS) and their parental cells (A2780). Methods: Cell viability was evaluated in the presence of different concentrations of fucoxanthin or cisplatin or fucoxanthin/cisplatin combination using the MTT assay. Propidium iodide staining and sub-G1 analysis were used to evaluate fucoxanthin potential for cell cycle modification and apoptosis induction in cancer cell lines. Results: The results showed that fucoxanthin was able to cause similar cell toxicity in both cell lines via apoptosis induction. Co-treatment of cells with cisplatin (3.125 to 100 µM) and nontoxic concentrations of fucoxanthin (1 and 2.5 µM) did not reverse resistance to cisplatin in A2780RCIS cells. Conclusion: Although fucoxanthin was not able to modify cisplatin-resistance in ovarian cancer cells, it was equally effective in inducing apoptosis and death in both A2780 and A2780RCIS cells indicating it is not an MRP2 substrate.

BACKGROUND: Chronic inflammation is considered to be a risk factor for carcinogenesis, tumor development and metastasis by providing tumor-related factors. OBJECTIVES: We aimed to evaluate the effect of cytokine interleukin-1β (IL-1β) as a key mediator of inflammation on multidrug resistance associated protein 2 (MRP2) expression and tamoxifen toxicity in estrogen receptor positive (ER+) MCF-7 breast cancer cells. METHODS: The effects of IL-1β on tamoxifen toxicity following 20-day treatment of MCF-7 cells with IL-1β and/or 17β-estradiol (E2) were measured by MTT assay. Furthermore, the effects of IL-1β and/or E2 on the mRNA expression and protein levels of MRP2 and NF-κB (p65) in breast cancer cells were evaluated by QRT-PCR and Western blot analysis, respectively. RESULTS: Treatment of breast cancer cells with IL-1β+ E2 decreased the sensitivity to 4-OH tamoxifen compared to both E2-treated and untreated cells. The mRNA expression levels of MRP2 and NF-κB (p65) were significantly increased following treatment with IL-1β+ E2, compared to control. In addition, breast cancer cells treatment with IL-1β+ E2 increased protein expression of MRP2 and it had no significant effect on NF-κB/p65 protein expression in these cells. CONCLUSION: Increased expression of mRNA and protein level of MRP2 following 20-day treatment of MCF-7 cells with IL-1β + E2 might be a possible elucidation for the increased tamoxifen resistance which was observed in these cells. More researches are essential to clarify the molecular mechanisms of inflammation on drug-resistance in the tumor environment in order to reducing or eliminating chemotherapy resistance and developing more effective treatment strategies.

Background Macrophages have plastic phenotypes. M1 macrophages release inflammatory cytokines and have microbicidal activities. M2 cells release anti-inflammatory cytokines and repair tissue damages. The imbalance between M1 and M2 responses has an important effect on many pathological events. Crocin is an antioxidant and can eliminate free radicals, the properties involved in its anti-inflammatory capacities. We investigated the effects of crocin on macrophages phenotype switching in view of their primary activation states. Methods The effect of crocin different concentrations on macrophage viability was evaluated by MTT. TNF-α and IL-6 secretion as well as iNOS/Arg-I ratio were measured in cells treated with crocin and or LPS + INF-γ (M1 inducers). The cytokine secretion levels and the ratio were also determined in cells concurrently treated with crocin and LPS + INF-γ or cells pretreated with crocin before M1 induction. Results Crocin did not show any toxicity at a concentration of 500 µM and lower. When M0 uncommitted macrophages were exposed to crocin (25–100 µM), it raised some M1 activity indicators including iNOS/Arg-I ratio and TNF-α secretion, but not IL-6. Crocin in concurrent treatment with LPS + INF-γ could halt raising in M1 indicators, iNOS/Arg-I ratio and TNF-α secretion. Pretreatment of cells by crocin before the addition of LPS + INF-γ, could not converse the M1 induction in macrophages and caused a further increase in iNOS/Arg-I ratio and TNF-α secretion. Conclusion It seems that crocin modulatory effects on macrophage M1/M2 phenotype switching at least partly depends on the presence or absence of inflammatory mediators and accordingly the preliminary state of macrophage commitment.

Objective(s): A new series of quinoline analogs of ketoprofen was designed and synthesized as multidrug resistance protein 2 (MRP2) inhibitors using ketoprofen as the lead compounds. Materials and Methods: The cytotoxic activity of the compounds was evaluated againt two cancer cell lines including A2780/RCIS (MRP2-overexpressing ovarian carcinoma), A2780, drug-sensitive ovarian carcinoma using MTT assay. Compounds showing low toxicity in MTT test were selected to investigate their MRP inhibition activity. MRP2 inhibitory potency was evaluated by determination of the uptake amount of fluorescent 5-carboxy fluorescein diacetate (5-CFDA) substrate, by A2780/RCIS in the presence of the selected compounds. Mode of interaction between synthesized ligands and homology modeled MRP2 was investigated by MOE software. Results: Compound 6d, a 4-carboxy quinoline possessing dimethoxy phenyl in position 2 of quinoline ring, showed the most MRP2 inhibition activity among all the quinolines and more than the reference drug ketoprofen. MRP2 inhibition activity of compound 7d was less in comparison to that of compound 6d, indicating that carboxyl group in position 4 of quinoline may interact with MRP2. Docking studies showed that compound 7d methyl ester of 6d, interacted less compared to its parent 6d, which is consistent with biological results. Conclusion: This study indicates that 6- or 8-benzoyl-2-arylquinoline is a suitable scaffold to design MRP2 inhibitors. The position of benzoyl in quinoline ring is important in inhibition of MRP2. Generally, MRP2 inhibition activity of compound 7d was less in comparison to that of 6d, indicating that carboxyl group in position 4 of quinoline may interact with MRP2.

Introduction Disease recurrence is an important obstacle in estrogen receptor positive (ER+) tamoxifen treated breast carcinoma patients. Tamoxifen resistance-related molecular mechanisms are not fully understood. Alteration in DNA methylation which contributes to transcriptional regulation of cancer-related genes plays a crucial role in tamoxifen response. In the present study, the contribution of promoter methylation and mRNA expression of PAX2 and AIB1 in the development of breast carcinoma and tamoxifen refractory was assessed. Methods Methylation specific-high resolution melting (MS-HRM) analysis and Real-time quantitative PCR (RT-qPCR) experiment were performed to analyze the promoter methylation and mRNA expression levels of PAX2 and AIB1 genes in 102 breast tumors and adjacent normal breast specimens. Results We indicated that PAX2 expression is decreased in breast tissues due to hypermethylation in its promoter region. Compared to the adjacent normal tissues, the tumors exhibited significantly lower relative mRNA levels of PAX2 and increased expression of AIB1. Aberrant promoter methylation of PAX2 and overexpression of AIB1 was observed in tamoxifen resistance patients compared to the sensitive ones. Cox regression analysis exhibited that the increased promoter methylation status of PAX2 and overexpression of AIB1 remained as unfavorable identifiers which influence patients' survival independently. Conclusions Our results revealed that the aberration in PAX2 promoter methylation and AIB1 overexpression are associated with the tamoxifen response in breast carcinoma patients. Further research is needed to demonstrate the potential of using PAX2 and AIB1 expression and their methylation-mediated regulation as predictive or prognostic biomarkers or as a new target therapy for better disease management.

Despite the discovery of a number of different mechanisms underlying tamoxifen resistance, its molecular pathway is not completely clear. The upregulation of SALL4 and Nodal has been reported in breast cancer. Nevertheless, their role in tamoxifen resistance has not been investigated. In the present study, we compared Nodal and SALL4 expression in 72 tamoxifen sensitive (TAMS) and tamoxifen-resistant (TAMR) patients. Afterward, the correlation of expression data with clinicopathological features and survival of patients was studied. Results showed that both SALL4 and Nodal were significantly upregulated in TAMR compared to TAMS patients. Besides, there was a positive association between Nodal and SALL4 expression. Furthermore, we evaluated their correlation with the expression of Oct4, Nanog and Sox2 stemness markers. The results demonstrated that in most tissue samples there was a positive correlation between Nodal and SALL4 expression with these stemness markers. Besides, the overexpression of SALL4 and Nodal significantly correlated with the N stage. Moreover, the overexpression of SALL4 was associated with extracapsular invasion and lymphatic invasion. High level expressions of SALL4 and Nodal had a significant association with worse disease-free survival (DFS) rates. In addition, increased level of Nodal expression provides a superior predictor factor for DFS. The multivariate Cox regression analysis also revealed that for DFS, perineural invasion (PNI) was independently an unfavorable prognostic value. These findings suggest that the high expression of SALL4 and Nodal could contribute to tamoxifen resistance and worse survival rates in tamoxifen-treated ER+ breast cancer patients.

Background: DNA methyltransferase (DNMT) enzymes, encoded by DNMT1, DNMT3A and DNMT3B genes, play a major role in the development of cancers through aberrant promoter methylation. Duo to little information about the biological and clinical significance of expression changes of these genes in Laryngeal Squamous Cell carcinoma (LSCC), the current study was designed to evaluate the contribution of DNMTs expression as potential diagnostic biomarkers in progression of LSCC. Methods: DNMT1, DNMT3A and DNMT3B expressions in tumoral and normal tissues from thirty-three LSCC patients were evaluated by relative comparative real-time PCR, prior to any therapeutic intervention. Relationship between genes expression and clinicopathological features were also analyzed. Results: We found the mRNA expression levels of all three DNMTs (DNMT1, DNMT3A and DNMT3B) were significantly elevated in LSCC tumor specimens compared to that of non-tumor tissues (P

Following antigen stimulation, naive CD4The human peripheral blood mononuclear cells were isolated using Ficoll density gradient centrifugation. MTT was used to evaluate the effect of 72-h treatment with different concentrations of crocin with or without ConA on lymphocytes proliferation. INF-γ/IL-4 cytokine secretion and T-bet/GATA-3 transcription factor expression ratios (as indicators of Th1/Th2 response status) were measured in non-stimulated and ConA-stimulated cells in the presence or absence of crocin by ELISA and RT-qPCR methods, respectively.The results showed crocin at a concentration of 50 μM and higher was toxic for human lymphocytes, and at a non-toxic concentration of 25 µM, it did not affect cell proliferation. The ratio of T-bet/GATA-3 and INF-γ/IL-4 was higher in the culture supernatant of ConA-stimulated cells compared to non-stimulated ones. Crocin-treated cells showed slightly lower T-bet/GATA-3 and INF-γ/IL-4 ratios compared to untreated cells. Crocin (25 μM) was also able to restore the increased ratio of Th1/Th2 immune response induced by ConA.Crocin can alleviate inflammatory-stimulant effects of ConA on human lymphocytes by decreasing T-bet/GATA-3 and INF-γ/IL-4 ratios, which are indicative of restoring the balance of Th1/Th2 responses.

Tamoxifen is the most important treatment component in estrogen receptor positive (ER+) breast carcinoma patients. Tamoxifen resistance incidence presents an important obstacle in clinical treatment. Mechanisms underlying tamoxifen refractory are not completely understood. Although elevated expression of Gankyrin (P28GANK) and stem cell markers Nanog, Oct-4 and Sox-2 have been reported in breast carcinoma, their role in tamoxifen resistance progression has not been explored. In the present study, P28GANK and stem cell markers Nanog, Oct-4 and Sox-2 expression were evaluated using quantitative RT-PCR and immunohistochemical technology in 72 breast carcinoma patients who received tamoxifen as adjuvant anti-hormone treatment. Expression data were correlated with the clinical outcome and survival of patients. Data analysis showed that P28GANK, Oct-4 and Sox-2 transcripts were significantly overexpressed in tamoxifen resistance patients. Immunohistochemical staining indicated that protein expression of P28GANK and Oct-4 were also significantly higher in tamoxifen resistance patients. We have shown a positive correlation between mRNA and protein expression of P28GANK, Oct-4 and Sox-2. Multivariate logistic regression analysis indicated that P28GANK (P = 0.002) and Oct-4 (P = 0.013) overexpression could be negative independent factors of disease outcome. Additionally, in the whole study group, multivariate Cox regression analysis revealed that high expression of P28GANK and Oct-4 remained significant and unfavorable predictive factors for patients’ survival. These findings suggest that Gankyrin and Oct-4 overexpression could promote tamoxifen refractory in breast cancer patients. More studies are warranted to clarify the predictive role of these potential biomarkers for patients who don’t benefit from tamoxifen treatment and their possible application as prognostic markers in ER+ tamoxifen-treated breast carcinoma patients.

Background: Signal transduction of numerous cytokines and growth factors are mediated by reactive oxygen species (ROS). Tumor necrosis factor-α (TNF-α) have stimulated accumulation of ROS in various in vitro studies. MCF-7 and its Adriamycin resistant variant MCF-7/ADR are resistant against TNF-α cytotoxicity. Role of ROS in the resistance of MCF-7 and MCF-7/ADR cells was investigated. Methods: ROS accumulation and viability in MCF-7 and MCF-7/ADR after TNF-α exposure was evaluated using 2',7'-dichlorofluorescein diacetate (DCFH-DA) as a fluorescent probe and 3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyltetrazolium bromide (MTT) cytotoxicity assay respectively. Results: ROS level did not change significantly after TNF-α exposure. Induction of ROS accumulation along with TNF-α treatment sensitized these cells to TNF-α toxicity. Conclusion: It can be concluded that lack of ROS accumulation following TNF-α exposure is involved at least by part in the resistance of MCF-7 and its drug resistant derivative MCF-7/ADR cells to TNF-α cytotoxicity.

Generating a protective and long-lasting immune response is the primary goal in the expanding field of immunotherapeutic research. In current study we designed an immunogenic bacteriophage- based vaccine to induce a cytotoxic T lymphocyte activity against a mice tumor model over-expressing HER2/neu. Bacteriophage λ displaying a HER2/neu derived peptide GP2 was constructed and used as an anti-cancer vaccine in a BALB/c mouse xenograft tumor model. The results of our study indicated that phage nanoparticles displaying GP2 as a fused peptide to the gpD phage capsid protein induced a robust CTL response. Furthermore, the chimeric phage nanoparticles protected mice against HER2/neu-positive tumor challenge in both prophylactic and therapeutic settings. In conclusion, we propose that λ phage nanoparticles decorated with GP2 peptide merit further investigation for the development of peptide-based vaccines against HER2/neu overexpressing tumors.

A newly designed series of imidazolyl-methyl- l-2,4-thiazolidinediones 9 (a-m) were synthesized and In Silico studies were carried out to rationalize their anti-diabetic activity. Generally, all newly synthesized thiazolidinediones had anti-hyperglycemic activity compared with a diabetic-control group, without toxicity in 3T3 cells (viability ≥ 90%). These studies revealed that the compounds 9e and 9b ( 11 ∗ 10 - 6 m o l / k g ) lowered blood glucose more effectively when compared to pioglitazone at the same dose. Following the administration of compound 9e, no weight gains or any serious side effects on liver and pancreas were observed. Moreover, the glucose consumption assay results showed a significant glucose-lowering effect (p

Novel imidazole-chalcone derivatives were designed and synthesized as tubulin polymerization inhibitors and anticancer agents. The antiproliferative activity of the imidazole-chalcone was assessed on some human cancer cell lines including A549 (adenocarcinoma human alveolar basal epithelial cells), MCF-7 (human breast cancer cells), MCF-7/MX (mitoxantrone resistant human breast cancer cells), and HEPG2 (human hepatocellular carcinoma cells). Generally, the imidazole-chalcone derivatives exhibited more cytotoxicity on A549 cancer cells in comparison to the other three cell lines, among them compounds 9j’ and 9g showed significant cytotoxicity with IC50 values ranging from 7.05 to 63.43 μM against all the four human cancer cells. The flow cytometry analysis of A549 cancer cells treated with 9g and 9j’ displayed that these compounds induced cell cycle arrest at the G2/M phase at low concentrations and increased the number of apoptotic cells (cells in subG1 phase) at higher concentrations. They have also inhibited tubulin polymerization similar to combretastatin A-4 (CA-4). Annexin V binding staining assay in A549 cancer cells revealed that compound 9j’ induced apoptosis (early and late). Finally, molecular docking studies of 9j’ into the colchicine-binding site of tubulin presented the probable interactions of these compounds with tubulin.

In the present day and age, cancer is still a life-limiting factor whose one of the therapeutic strategies is immunotherapy with vaccines. This research aims to prepare and characterize nanoliposomal vaccine formulation attached to HER2/neu-derived peptide (AE36) with or without CpG-ODN, and to evaluate its immunological responses to the therapy using BALB/c mice with HER2 overexpressing breast cancer. Methods: AE36 was conjugated to the liposomes containing DOTAP, DOPE and Cholesterol. Such formulations are able to produce CD8+ and CD4+ responses and induce synthesis of cytokines detectable via Enzyme-linked immunosorbent assay kits, cytotoxicity testing and intracellular cytokine staining combined with flow cytometry. Therapeutic and prophylactic effectiveness were evaluated through the formulation in samples. The highest effectiveness was found in DDC-peptide + CpG-ODN in both prophylactic and therapeutic studies, which decreased the size of tumors significantly and increased time of survival. These nanoliposomes linked to AE36 could be regarded as an appropriate candidate for the treatment and also for prophylaxis of HER2+ breast cancer; however further studies are needed.

Objective(s): Resistance to medications is one of the main complications in chemotherapy of cancer. It has been shown that some multidrug resistant cancer cells indicate more sensitivity against cytotoxic effects of TNF-α compared to their parental cells. Our previous findings indicated vulnerability of the mitoxantrone-resistant breast cancer cells MCF-7/MX to cell death induced by TNF-α compared to the parent cells MCF-7. In this study, we performed a comparative proteomics analysis for identification of proteins involved in induction of higher susceptibility of MCF-7/MX cells to cytotoxic effect of TNF-α. Materials and Methods: Intensity of protein spots in 2D gel electrophoresis profiles of MCF-7 and MCF-7/MX cells were compared with Image Master Platinum 6.0 software. Selected differential protein-spots were identified with MALDI-TOF/TOF mass spectrometry and database searching. Pathway analyses of identified proteins were performed using PANTHER, KEGG PATHWAY, Gene MANIA and STRING databases. Western blot was performed for confirmation of the proteomics results. Results: Our results indicated that 48 hr exposure to TNF-α induced 87% death in MCF-7/MX cells compared to 19% death in MCF-7 cells. Forty landmarks per 2D gel electrophoresis were matched by Image Master Software. Six proteins were identified with mass spectrometry. Western blot showed that 14-3-3γ and p53 proteins were expressed higher in MCF-7/MX cells treated with TNF-α compared to MCF-7 cells treated with TNF-α. Conclusion: Our results showed that 14-3-3 γ, prohibitin, peroxiredoxin 2 and P53 proteins which were expressed differentially in MCF-7/MX cells treated with TNF-α may involve in the induction of higher rates of cell death in these cells compared to TNF-α-treated MCF-7 cells.

A new series of styrylquinolines was designed and synthesized as anticancer agents and tubulin polymerization inhibitors. The in vitro anticancer activity of the synthesized quinolines was evaluated against four human cancer cell lines including A-2780 (human ovarian carcinoma), A-2780/RCIS (cisplatin resistant human ovarian carcinoma), MCF-7 (human breast cancer cells), MCF-7/MX (mitoxantrone resistant human breast cancer cells) and normal Huvec cells. Generally, among the forty-eight newly synthesized quinolines, compounds possessing N-trimethoxy phenyl showed stronger cytotoxic activity with IC50 values ranging from 0.38 to 5.01 μM against all four cancer cell lines. Compounds 9VII-c and 9IV-c showed significant cytotoxic activity on A-2780 cancer cells, stronger than the other compounds and comparable to reference drug CA-4. Compound 9IV-c possessing 3,4-dimethoxystyryl and N-trimethoxy phenyl groups demonstrated potent cytotoxic effects with IC50 values ranging from 0.5 to 1.66 µM on resistant cancer cells as well as their parental cells. Annexin V binding staining assay in A-2780 and MCF-7/MX cancer cells, revealed that compound 9IV-c induced early and late apoptosis. Compounds 9IV-c and 9VII-b, inhibited tubulin polymerization similar to CA4. Finally, molecular docking studies of 9IV-c and 9VII-b into the colchicine-binding site of tubulin displayed the possible interactions of these compounds with tubulin.

The main obstacles that lead to clinical failure in cancer treatment are the development of resistant to chemotherapy and a rise in invasive characteristics in cancer tumor cells due to prolonged chemotherapeutic processes. Recent studies have revealed some evidence about the existence of a direct relationship between development of drug resistance and triggering of invasive capability in tumor cells. Therefore, devising and application of chemotherapeutic procedures that are not prone to the development of chemotherapy resistance are necessary. Here, we focus on CD147, CD44, ANAX2, P-gp, MMPs, and UCH-L1 proteins involved in the crosstalk between metastasis and cancer treatment. We think that further structural and functional analysis of these proteins may direct scientists towards designing highly effective chemotherapy procedures.

PAX2 (paired box gene 2) is a transcription factor, which is involved in both cell proliferation and carcinogenesis. This study aimed to investigate PAX2 expression in tamoxifen resistant (TAM-R) and tamoxifen sensitive (TAM-S) breast carcinoma patients and analyze its correlation with clinicopathological characteristics and survival. Immunohistochemical analysis was performed to evaluate PAX2 protein expression in 36 TAM-R and 36 TAM-S formalin-fixed paraffin-embedded (FFPE) breast tumor tissues. Data analysis indicated that PAX2 expression was significantly higher in TAM-S group in comparison to TAM-R (P = 0.014). Overexpression of PAX2 was significantly correlated with perineural invasion (PNI) (P = 0.025). Kaplan-Meier survival analysis showed significant association between high expression of PAX2 and better disease-free survival (P 0.001) and also overall survival (P = 0.031). Multivariate cox regression analysis demonstrated that patients with increased expression of PAX2 have a trend toward improved disease free survival (OR = 0.065, 95% CI: 0.009-0.476; P = 0.007) and overall survival (OR = 0.147, 95% CI: 0.020-1.105; P = 0.062). Our data suggested that high expression of PAX2 could be associated with better survival in estrogen receptor positive tamoxifen-treated breast carcinoma patients.

We have investigated the in vitro immunogenicity and in vivo prophylactic and therapeutic potential of lambda (λ) phage particles displaying the E75 peptide (derived from HER2 protein) in an implantable TUBO breast tumor model of BALB/c mice. The mice were immunized with the E75-displaying phage (λF7-gpD::E75) every 2-week intervals over a 6-week period, and the generated immune responses were studied. Results showed in vitro induction of immune responses by the λF7 (gpD::E75) construct compared to the control λF7 and buffer groups. In the in vivo prophylactic study, all the control and vaccinated mice groups developed tumors. However, in the therapeutic experiments, we observed a significant difference in tumor size at days 14–36 for mice immunized with λF7 (gpD::E75) compared to control groups (P

E75 (HER-2/neu-369-377), is an immunogenic peptide which is highly expressed in breast cancer patients. The purpose of this study was to develop an effective vaccine delivery/adjuvant system by attachment of this peptide to the surface of liposomes consisting of phospholipids including distearoylphosphocholine (DSPC) and distearoyl phosphoglycerol (DSPG) with high transition temperature (Tm) and dioleoylphosphatidylethanolamine (DOPE) (a pH-sensitive lipid for cytosolic antigen delivery) to improve antitumour immune activity against the E75 peptide. For this purpose, the E75 peptide was incorporated into liposomes consisting of DSPC/DSPG/cholesterol (Chol)/DOPE (15/2/3/5 molar ratio) through conjugation with distearoylphosphoethanolamine-N-[maleimide(polyethylene glycol)-2000] (maleimide-PEG2000-DSPE). Immunization of BALB/c mice was performed three times with different forms of liposomal formulations at 2-week intervals and antitumour immunity responses were evaluated. Results of ELISpot and flow cytometry analysis showed that mice vaccinated with DSPC/DSPG/Chol/DOPE/E75 have significantly enhanced the antigen-specific IFN-γ response of CD8+ T cells and generated cytotoxic T lymphocytes (CTL) antitumour responses. CTL responses induced by this formulation resulted in inhibition of tumour progression and longer survival time in the mice TUBO tumour model. The results revealed that the liposomes consist of DSPC/DSPG/Chol/DOPE could be suitable candidates for vaccine delivery of E75 peptide for the prevention and therapy of HER2-positive breast cancer and merit further investigation.

This study was designed to prepare and characterize nanoliposomal vaccine formulation encapsulating AE36 HER2/neu-derived peptide with or without CpG and evaluate the immunologic and therapeutic responses of that in BALB/c mice model of Her2 overexpressing breast cancer. AE36 was encapsulated in liposomes composed of DOTAP, DOPE and Cholesterol (DDC) or DD with. The formulations could induce both CD8+ and CD4+ responses and stimulate production of cytokines which was detected by Enzyme-linked immunospot assay (ELISpot) kits, cytotoxicity test and intracellular cytokine assay by flow cytometry. The formulation showed both therapeutic and prophylactic effects in BALB/c mice bearing Her2+ breast cancer. DDC+CpG showed the best effect in prophylactic study and DD+pG showed the best effect in therapeutic study, which both of them decreased the size of tumors significantly. The engineered nanoliposomes containing AE36 could be a candidate vaccine for the treatment or prophylaxis of HER2+ breast cancer and merits further investigation.

Tumor necrosis factor-α (TNF-α) is a cytokine involved in the various physiopathological processes such as autoimmune disorders and inflammation related diseases. Some multidrug resistant (MDR) cancer cell lines including MCF-7/MX are more vulnerable to cytotoxic effects of TNF-α than their parental lines. In this study, breast cancer cell line MCF-7 and its MDR derivative MCF-7/MX were exposed to TNF-α afterward various downstream signaling mediators of TNF-α were analyzed. Although, treatment of MCF-7 cells with TNF-α activated NF-kB and caused RIP1 ubiquitination, TNF-α exposure led to JNK and RIP1 phosphorylation in MCF-7/MX cells. In both cell lines TNF-α did not activate the caspase cascade. Moreover, AnexinV/PI analysis showed that cytotoxic effects of TNF-α on MCF-7/MX is mediated via apoptosis independent mechanisms and inhibition of RIP1 kinase activity using necrostatin-1 revealed that kinase activity of RIP1 plays role in the production of ROS, activation of JNK and cellular death following exposure of MCF-7/MX cells to TNF-α. Overall, it seems that RIP1 ubiquitination and NF-kB activation are prosurvival signaling mediators protecting MCF-7 cells against cytotoxic effects of TNF-α while TNF-α drives MCF-7/MX cells to non-apoptotic cellular death via kinase activity of RIP1, activation of JNK and ROS production.

Breast cancer is the most frequent cancer in women. Despite advances in early detection and treatment, it has the second highest mortality rate after lung cancer. Around 85% of breast carcinomas are ER+; thus, antiestrogens like tamoxifen are beneficial. Although, tamoxifen is useful for many patients, a number of patients respond poorly to initial therapy or recurrence occurs in about 30% of cases, because tamoxifen resistance happens. Drug resistance remains a major clinical obstacle to successful treatment of breast cancer and more than 90% of unsuccessful treatments are because of acquired resistance and MultiDrug Resistance (MDR) is a major contributor. MicroRNAs are members of a novel class of short noncoding RNAs. Besides their various roles in gene expression, miRNAs are considered as important cancer therapeutic targets and biomarkers. Since 2005, when miRNA deregulation was first reported in breast cancer, more than 1000 reports have been published about miRNAs. Increasing number of studies showed the importance of miRNAs in antiestrogen therapy, especially on tamoxifen; thus, it is not surprising that these tiny molecules are involved in drug resistance. Due to the pivotal role of these known RNA molecules, in this review, we tried to illustrate the importance of the miRNAs as a new player in breast cancer pathogenesis. We have also focused on cancer drug resistance mechanisms highlighting the role of important oncomirs, miR 221/222, involved in cell cycle deregulation in breast cancer. The relationship between these oncomiRs with resistance to tamoxifen is also emphasized.

Glucosamine (GlcN) is a natural amino monosaccharide in the human body, and evidence of its anticancer effects is growing. In this study, we aimed to evaluate the effects of GlcN for its cytotoxicity, MDR reversal effects and inhibitory effects on function and expression of P-glycoprotein (P-gp) transporter in the daunorubicin-resistant human gastric cancer cells. Cell viability was measured by MTT assay to evaluate the cytotoxicity and multidrug resistance (MDR) reversal effects of GlcN. The effects of GlcN on function and mRNA expression level of P-gp transporter were assessed by flow cytometry and real-time RT-qPCR, respectively. Our results indicated that GlcN reduced the proliferation of human gastric cancer cell line EPG85-257 and its drug-resistant variant EPG85-257RD in a dose-dependent manner. GlcN (at the concentrations of 0.5 and 1 mM) also enhanced the sensitivity of EPG85-257RDB cells to daunorubicin. The cellular accumulation studies showed that GlcN inhibited efflux activity of P-gp and enhanced the mean fluorescent intensity of Rho123 while

A new series of quinoline-chalcone hybrids was synthesized. The structures of these compounds were characterized by spectroscopic methods including 1H and 13CNMR and mass spectroscopy. The cytotoxic activity of compounds was evaluated against four human cancer cell lines including A2780 (human ovarian carcinoma) and A2780/RCIS (Cisplatin resistant human ovarian carcinoma), MCF-7 (human breast cancer cells), MCF-7/MX (Mitoxantrone resistant human breast cancer cells) and normal Huvec cells. The structure-activity relationship of synthesized compounds is discussed. Among quinolines 5e, 5g and 5j possessing benzoyl group showed significant cytotoxic activity against both resistant cancer cells and their parents. Compounds 5g and 5j, demonstrated the most antiproliferative activity with IC50 values ranging from 2.32 to 22.4 μM. They were also identified as tubulin inhibitors and induced cell cycle arrest at G2/M phase and apoptosis. Compound 5j induced more arrest at G2/M phase in four cancer cell lines compared to compound 5g. Finally, molecular dynamics simulation and molecular docking studies of compound 5j into the colchicine-binding site of tubulin demonstrated the possible interaction of this compound in the active site of tubulin.

Glucosamine (GlcN), a natural amino sugar in human body, was reported to exhibit anticancer activity against some tumors. In the present study, we evaluated the cytotoxicity and multi-drug resistance (MDR) reversal activity of GlcN on resistant MRP2-overexpressing ovarian cancer A2780RCIS cells. The cytotoxicity and MDR reversal activity of GlcN on cancer cells were measured by MTT assay. The effects of GlcN on MRP1 and MRP2 mRNA expression and function were evaluated by qRT-PCR and flow cytometry, respectively. The cell migration capacity of ovarian cancer cells were assessed in the presence or absence of GlcN using wound healing migration assay. Furthermore, the effects of GlcN on the mRNA expression of E-cadherin, vimentin and α -smooth muscle actin as Epithelial-Mesenchymal Transition (EMT)-related markers were evaluated by qRT-PCR. Our results indicated that glucosamine reduced the proliferation of human ovarian cancer cell lines (A2780) and its cisplatin resistant variant (A2780RCIS) in a dose-dependent manner. The IC50 values for A2780RCIS cells treated with cisplatin in the presence of different concentrations of GlcN (0, 1, 2 and 3 mM) for 72 h were 44.463 ± 1.603, 35.17 ± 0.025, 22.25 ± 0.018, 17.78 ± 0.012 μM respectively. Also GlcN decreased the expression of MRP1 and MRP2 mRNA in ovarian cancer cells. Our results further demonstrated that although GlcN had no significant effects on the expression of studied EMT-related markers in invasive A2780RCIS cells, it was able to inhibit their migration in vitro. According to these findings, GlcN could effectively enhance cisplatin cytotoxicity in resistant A2780RCIS cells.