Human-derived Tumor-On-Chip model to study the heterogeneity of breast cancer tissue

One of the leading causes that complicate the treatment of some malignancies, including breast cancer, is tumor heterogeneity. In addition to inter-heterogeneity and intra-heterogeneity of tumors that reflect the differences between cancer cell characteristics, heterogeneity in the tumor microenvironment plays a critical role in tumor progression and could be considered an overlooked and a proper target for the effective selection of therapeutic approaches. Due to the difficulty of completely capturing tumor heterogeneity in conventional detection methods, Tumor-on-Chip (TOC) devices with culturing patient-derived spheroids could be an appropriate alternative. In this research, human-derived spheroids from breast cancer individuals were cultured for 6 days in microfluidic devices. To compare TOC data with conventional detection methods, immunohistochemistry (IHC) and ITRAQ data were employed, and various protein expressions were validated using the transcriptomic databases. The behavior of the spheroids in the collagen matrix and the cell viability were monitored over 6 days of culture. IHC and immunocytochemistry (ICC) results revealed that inter and intra-heterogeneity of tumor spheroids are associated with HER2/ER expression. HER2 expression levels revealed a more important biomarker associated with invasion in the 3D culturing of spheroids. The expression levels of CD163 (as a marker for Ma2 macrophages) and CD44 (a marker for cancer stem cells (CSCs)) were also evaluated. Interestingly, the levels of M2a macrophages and CSCs were higher in triple-negative specimens and samples that showed higher migration and invasion. Cell density and extracellular matrix (ECM) stiffness were also important factors affecting the migration and invasion of the spheroids through the matrix. Among these, rigid ECM revealed a more crucial role than cell density. To sum up, these research findings demonstrated that human-derived spheroids from breast cancer specimens in microfluidic devices provide a dynamic condition for predicting tumor heterogeneity in patients, which can help move the field forward for better and more accurate therapeutic strategies.

In-vivo anticancer efficacy of self-targeted methotrexate-loaded polymeric nanoparticles in solid tumor-bearing rat

Here, cytotoxicity and antitumor efficacy against a chemically (N-methyl-N-nitrosourea) generated mammary tumor in rats were assessed using methotrexate-loaded chitosan nanoparticles (Meth-Cs-NPs). Meth-Cs-NPs intravenous administrated resulted in noticeably decreased tumor incidence, multiplicity, and weight. Further, kidney function tests for the treated groups resulted in noticeably decreased ALP (Meth-Cs-NPs; 244 ± 15, diseases control; 403 ± 14 U/L), Creatinine (Meth-Cs-NPs; 0.81 ± 0.05, diseases control; 2 ± 0.05 mg/dl), and Urea (Meth-Cs-NPs; 56.62 ± 5, diseases control; 113 ± 6 mg/dl) levels, close to a normal control group. Similarly, liver function tests showed significantly decreased serum biomarkers, SGPT (Meth-Cs-NPs; 40 ± 1.8, diseases control; 84 ± 1.9 U/L) and SGOT (Meth-Cs-NPs; 15 ± 2, diseases control; 55 ± 4 U/L) levels in treated groups as compared to the untreated group (diseases control). From the results, pro-inflammatory cytokines were also markedly reduced in the treated group such as, TNF-α (Meth-Cs-NPs; 17.31 ± 1.15, diseases control; 36.9 ± 5 pg/mL), IL-1β (Meth-Cs-NPs; 433.3 ± 66.5, diseases control; 1540 ± 131.1 pg/mL), and IL-6 (Meth-Cs-NPs; 1515 ± 53, diseases control; 2200.6 ± 69 pg/mL) levels. Whereas Meth-Cs-NPs not only helped in lowering tumor multiplicity rates but also decrease inflammation. The studies could be successfully performed in chemically induced mammary tumors due to their easy, quick tumor growth and low mortality rates in rat models. According to the current study, Meth-Cs-NPs have high treatment potency and represent a possible therapeutic alternative for breast cancer treatment.

Construction and Validation of Angiogenesis-Related Prognostic Risk Signature to Facilitate Survival Prediction and Biomarker Excavation of Breast Cancer Patients

This study is aimed at exploring the potential mechanism of angiogenesis, a biological process-related gene in breast cancer (BRCA), and constructing a risk model related to the prognosis of BRCA patients. We used multiple bioinformatics databases and multiple bioinformatics analysis methods to complete our exploration in this research. First, we use the RNA-seq transcriptome data in the TCGA database to conduct a preliminary screening of angiogenesis-related genes through univariate Cox curve analysis and then use LASSO regression curve analysis for secondary screening. We successfully established a risk model consisting of seven angiogenesis-related genes in BRCA. The results of ROC curve analysis show that the risk model has good prediction accuracy. We can successfully divide BRCA patients into the high-risk and low-risk groups with significant prognostic differences based on this risk model. In addition, we used angiogenesis-related genes to perform cluster analysis in BRCA patients and successfully divided BRCA patients into three clusters with significant prognostic differences, namely, cluster 1, cluster 2, and cluster 3. Subsequently, we combined the clinical-pathological data for correlation analysis, and there is a significant correlation between the risk model and the patient’s T and stage. Multivariate Cox regression curve analysis showed that the age of BRCA patients and the risk score of the risk model could be used as independent risk factors in the progression of BRCA. In particular, based on this angiogenesis-related risk model, we have drawn a matching nomogram that can predict the 5-, 7-, and 10-year overall survival rates of BRCA patients. Subsequently, we performed a series of pan-cancer analyses of CNV, SNV, OS, methylation, and immune infiltration for this risk model gene and used GDSC data to explore drug sensitivity. Subsequently, to gain insight into the protein expression of these risk model genes in BRCA, we used the immunohistochemical data in the THPA database for verification. The results showed that the protein expressions of IL18, RUNX1, SCG2, and THY1 molecules in BRCA tissues were significantly higher than those in normal breast tissues, while the protein expressions of PF4 and TNFSF12 molecules in BRCA tissues were significantly lower than those in normal breast tissues. Finally, we conducted multiple GSEA analyses to explore the biological pathways these risk model genes can cross in cancer progression. In summary, we believe that this study can provide valuable data and clues for future studies on angiogenesis in BRCA.

Expression level and potential target pathways of miR-1-3p in colorectal carcinoma based on 645 cases from 9 microarray datasets

For the purpose of demonstrating the clinical value and unraveling the molecular mechanisms of micro RNA (miR)-1-3p in colorectal carcinoma (CRC), the present study collected expression and diagnostic data from Gene Expression Omnibus (GEO), ArrayExpress and existing literature to conduct meta-analyses and diagnostic tests. Furthermore, the potential targets of miR-1-3p were attained from datasets that transfected miR-1-3p into CRC cells, online prediction databases and differentially expressed genes from The Cancer Genome Atlas and literature. Subsequently, bioinformatics analysis was conducted based on the aforementioned selected target genes. As a result, downregulation of miR-1-3p was observed. The combined standardized mean difference was −0.51 with 95% confidence interval (CI) of −0.68 to −0.33 using a fixed effect model, which demonstrated a significant downregulation of miR-1-3p in CRC. The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio diagnostic score and odds ratio were 0.74 (95%CI: 0.48, 0.90), 0.75 (95%CI: 0.35, 0.94), 2.94 (95%CI: 1.01, 8.55), 0.34 (95%CI: 0.19, 0.60), 2.15 (95%CI: 1.06, 3.23) and 8.57 (95%CI: 2.89, 25.36). The summarized receiver operating characteristic curve demonstrated that the area under the curve was 0.81. In bioinformatics analyses based on 30 promising targets, the most enriched terms in Gene Ontology were positive regulation of transcription from RNA polymerase II promoter, extracellular region and transcription factor binding. Kyoto Encyclopedia of Genes and Genomes pathway analysis highlighted the pathway termed cytokine-cytokine receptor interaction. In protein-protein interaction analysis, platelet factor 4 was selected as the hub gene. To conclude, miR-1-3p is downregulated in CRC and likely suppresses CRC via multiple biological approaches, which indicates the diagnostic potential and tumor suppressive efficacy.

Cellular and Molecular Changes in MNU-Induced Breast Tumours Injected with PF4 or bFGF

Background: Angiogenic activity has been considered to reflect important molecular events during breast tumour development. The present study concerned cellular and molecular changes of MNU-induced breast tumours subjected to promotion and suppression of angiogenesis. Methods: Female Sprague Dawley rats at the age of 21 days received MNU at the dose 70 mg/kg of body weight by intraperitoneal injection. Three months post-carcinogen initiation, mammary tumours were palpated and their growth was monitored. When the tumour diameter reached 1.0 ± 0.05 cm, rats were given bFGF or PF4 intratumourally at a dose of 10 μg/tumour. Entire palpable tumour were subsequently excised and subjected to histology examination, IHC staining, and RT-PCR. Results: No critical morphological changes were observed between pro-angiogenic factor, bFGF, and control groups. However, increase of tumour size with more necrotic and diffuse areas was notable in tumours after anti-angiogenic PF4 intervention. ER and PR mRNA expression was significantly up- and down-regulated in bFGF and PF4 groups, respectively. The trends were significantly associated with peri- and intratumoural MVD counts. However, irrespective of whether we promoted or inhibited angiogenesis, the expression of EGFR and ERBB2 continued to be significantly increased but this was not significantly associated with the MVD score. No significant differences in E-cadherin and LR gene expression were noted between intervention and control groups. Conclusion: ER and PR receptor expression shows consistent responses when tumour angiogenesis is manipulated either positively or negatively. Our study adds to current understanding that not only do we need to target hormonal receptors, as presently practiced, but we also need to target endothelial receptors to successfully treat breast cancer.

Effects of rapamycin on cell apoptosis in MCF-7 human breast cancer cells

BACKGROUND

Rapamycin is an effective anti-angiogenic drug. However, the mode of its action remains unclear. Therefore, in this study, we aimed to elucidate the antitumor mechanism of rapamycin, hypothetically via apoptotic promotion, using MCF-7 breast cancer cells.

MATERIALS AND METHODS

MCF-7 cells were plated at a density of 15105 cells/well in 6-well plates. After 24h, cells were treated with a series of concentrations of rapamycin while only adding DMEM medium with PEG for the control regiment and grown at 37oC, 5% CO2 and 95% air for 72h. Trypan blue was used to determine the cell viability and proliferation. Untreated and rapamycin-treated MCF-7 cells were also examined for morphological changes with an inverted-phase contrast microscope. Alteration in cell morphology was ascertained, along with a stage in the cell cycle and proliferation. In addition, cytotoxicity testing was performed using normal mouse breast mammary pads.

RESULTS

Our results clearly showed that rapamycin exhibited inhibitory activity on MCF-7 cell lines. The IC50 value of rapamycin on the MCF-7 cells was determined as 0.4μg/ml (p<0.05). Direct observation by inverted microscopy demonstrated that the MCF-7 cells treated with rapamycin showed characteristic features of apoptosis including cell shrinkage, vascularization and autophagy. Cells underwent early apoptosis up to 24% after 72h. Analysis of the cell cycle showed an increase in the G0G1 phase cell population and a corresponding decrease in the S and G2M phase populations, from 81.5% to 91.3% and 17.3% to 7.9%, respectively.

CONCLUSIONS

This study demonstrated that rapamycin may potentially act as an anti-cancer agent via the inhibition of growth with some morphological changes of the MCF-7 cancer cells, arrest cell cycle progression at G0/G1 phase and induction of apoptosis in late stage of apoptosis. Further studies are needed to further characterize the mode of action of rapamycin as an anti-cancer agent.

Upregulation of HIF-1α by hypoxia protect neuroblastoma cells from apoptosis by promoting survivin expression

Apoptosis is one of main types of neural cell death and is reversible and is a major target of therapeutic interventions. However, detailed apoptotic cascades still need to be recognized. In present study, we determined the promotion of HIF-1α and survivin in brain samples of a mouse model of hypoxic-ischemia and in neuroblastoma SH-SY5Y cells post hypoxia treatment. Then gain-of-function and loss-of-function strategies were adopted to manipulate the HIF-1α in SH-SY5Y cells, and hypoxia-induced survivin upregulation and cell apoptosis were determined. Results demonstrated that the HIF-1α and survivin were significantly promoted in a mouse model of hypoxic-ischemia or in SH-SY5Y cells post hypoxia in vitro. Manually upregulated HIF-1α could promote the hypoxia-induced survivin upregulation and improve the hypoxia-induced SH-SY5Y cell apoptosis. On the other hand, the HIF-1α knockdown by RNAi reduced the hypoxia-induced survivin upregulation and cell apoptosis. Therefore, the present study confirmed the protective role of HIF-1α and survivin in the hypoxia-induced SH- SY5Y cell apoptosis, and the survivin upregulation by hypoxia is HIF-1α-dependent. Promotion of HIF-1α and survivin might be a valuable stragegy for therapeutic intervention for hypoxic-ischemic encephalopathy.