PI3K/AKT and MAPK1 molecular changes preceding matrix metallopeptidases overexpression during tamoxifen-resistance development are correlated to poor prognosis in breast cancer patients

An uncertainty-based interpretable deep learning framework for predicting breast cancer outcome

BACKGROUND

Predicting outcome of breast cancer is important for selecting appropriate treatments and prolonging the survival periods of patients. Recently, different deep learning-based methods have been carefully designed for cancer outcome prediction. However, the application of these methods is still challenged by interpretability. In this study, we proposed a novel multitask deep neural network called UISNet to predict the outcome of breast cancer. The UISNet is able to interpret the importance of features for the prediction model via an uncertainty-based integrated gradients algorithm. UISNet improved the prediction by introducing prior biological pathway knowledge and utilizing patient heterogeneity information.

RESULTS

The model was tested in seven public datasets of breast cancer, and showed better performance (average C-index = 0.691) than the state-of-the-art methods (average C-index = 0.650, ranged from 0.619 to 0.677). Importantly, the UISNet identified 20 genes as associated with breast cancer, among which 11 have been proven to be associated with breast cancer by previous studies, and others are novel findings of this study.

CONCLUSIONS

Our proposed method is accurate and robust in predicting breast cancer outcomes, and it is an effective way to identify breast cancer-associated genes. The method codes are available at: https://github.com/chh171/UISNet .

miR-125b-5p-MAPK1-C/EBPα feedback loop regulates all-trans retinoic acid resistance in acute promyelocytic leukemia

BACKGROUND

Various studies have highlighted the significance of miR-125b-5p in tumour chemotherapy resistance; However, whether miR-125b-5p is associated with all-trans retinoic acid (ATRA) resistance in acute promyelocytic leukemia (APL) has not been reported.

METHODS

Drug-resistance-related factors in APL were predicted using the DRESIS database. The expression levels of miR-125b-5p in ATRA-sensitive and ATRA-resistant APL cells were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR). A nitrotetrazolium blue (NBT) reduction assay and flow cytometry (FCM) were used to detect the effect of miR-125b-5p on ATRA resistance in APL cells. An APL xenograft tumour mouse model was established to determine the effect of miR-125b-5p on ATRA resistance. A dual-luciferase gene reporter assay, qRT-PCR, and western blotting verified the regulation by miR-125b-5p of its target gene, MAPK1, and the MAPK1 downstream factor, C/EBPα. An NBT reduction assay and FCM were used to detect the effect of C/EBPα on ATRA resistance in APL cells. Western blotting and qRT-PCR were used to assess the regulation of miR-125b-5p and MAPK1 by C/EBPα.

RESULTS

miR-125b-5p expression levels were dramatically increased in ATRA-resistant APL cells. Both in vitro and in vivo experiments revealed that miR-125b-5p overexpression enhanced ATRA resistance in APL. miR-125b-5p promoted ATRA resistance by sponging MAPK1. C/EBPα was negatively regulated by miR-125b-5p, which in addition, regulated ATRA resistance in APL cells. C/EBPα also regulated the miR-125b-5p-MAPK1 axis.

CONCLUSION

The findings of this study indicate that the miR-125b-5p-MAPK1-C/EBPα feedback loop regulated ATRA resistance in APL. Thus, miR-125b-5p may be a promising target for treating ATRA resistance in APL.

Synergistic effects of ozone with doxorubicin on the proliferation, apoptosis and metastatic profile of luminal-B type human breast cancer cell line

OBJECTIVE

Luminal-B type human breast cancer cell line (BT-474) to assess the synergistic effects of ozone applied after chemotherapeutic treatment with various dosages of doxorubicin, and compare the results with the effects on L929 fibroblast cell line.

METHODS

Doxorubicin (1-50 M) was added to each cell lines and left to sit for 24 h at 37 °C. Then, as combination groups, half of the groups were incubated with 30 g/mL ozone for 25 min. Tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-β), and matrix metalloproteinase-2 and - 9 (MMP-2 and MMP-9) levels were measured using the MTT test, flow cytometry, and immunocytochemistry, respectively.

RESULTS

When compared to simply doxorubicin-applied cells without ozone treatment, each dose of doxorubicin + ozone treatment considerably boosted L929 viability but significantly decreased BT-474 viability. Additionally, the combination increased the apoptotic impact of doxorubicin on BT-474 but not L929 (P < 0.001). TGF-, MMP-2, and MMP-9 levels of L929 after combination were substantially higher than those of the other groups (P < 0.01). Doxorubicin's effect on BT-474's protein levels, which had significantly decreased in comparison to those of the other groups, was reversed by the combination treatment (P < 0.05).

CONCLUSION

Doxorubicin's anti-proliferative and apoptotic effects were enhanced by ozone treatment in BT-474 cells, but it also repaired and healed healthy fibroblast cells that had been harmed by the cytotoxicity of the chemotherapy drug. If doxorubicin and ozone treatment are coupled, BT-474 cells may develop resistance to it through expressions of TNF-α, TGF-β, MMP-2, and MMP-9.

Immune system and tumor microenvironment in early-stage breast cancer: different mechanisms for early recurrence after mastectomy and chemotherapy on ductal and lobular types

Background: The most common type of breast cancer is the ductal type (IDC), followed by lobular type (ILC). Surgery is the main therapy for early-stage breast cancer. Adjuvant chemotherapy might be given to those at high risk of recurrence. Recurrence is still possible after mastectomy and chemotherapy and most often occurs in the first two years. We aimed to determine the mechanisms in early local recurrence in both types. Methods: We used an observational method with a cross-sectional study design. The samples were patients with early-stage IDC and ILC, who underwent modified radical mastectomy (MRM) and got adjuvant chemotherapy with taxan and anthracycline base, and experienced recurrence in the first two years after surgery. The materials in this study were paraffin blocks from surgical specimens; we examined vimentin, α-SMA and MMP1, PDGF and CD95 by immunohistochemistry (IHC). Data analysis was done using OpenEpi 3.0.1 and EZR. We used pathway analysis with linear regression. Results: There were 25 samples with local recurrence and 25 samples without recurrence in the ductal type group. The lobular type group consisted of six subjects without recurrence and seven with recurrence. There were significant differences in the expression of vimentin (p=0.000 and 0.021, respectively), PDGF (p=0.000 and 0.002) and CD95 (p=0.000 and 0.045) in ductal and lobular cancer types, respectively. MMP1 (p=0.000) and α-SMA (p=0.000) only showed a significant difference in the ductal type. The pathway analysis showed that in the ductal type, the mechanism of recurrence was enabled by two factors: α-SMA and CD95. Meanwhile, for the lobular type, the recurrence mechanism was through the CD95 pathway. Conclusions: Local recurrence in early-stage IDC and ILC had different mechanisms.  These findings are expected to make cancer treatment in both types more focused and efficient.

Berberine Inhibited Growth and Migration of Human Colon Cancer Cell Lines by Increasing Phosphatase and Tensin and Inhibiting Aquaporins 1, 3 and 5 Expressions

Introduction: Berberine is a natural isoquinoline alkaloid with anti-cancer properties. Nevertheless, the underlying mechanism of its action in human colorectal cancer (CRC) has not been thoroughly elucidated. We investigated the anti-cancer effect of berberine on HT-29, SW-480 and HCT-116 human CRC cell lines. Methods: Cell proliferation, migration and invasion were studied by MTT assay, wound healing, transwell chambers and flow cytometry. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunostaining were used to evaluate the expression of aquaporins (AQPs) 1, 3 and 5 in colon cancer cell lines before and after treatment with berberine (10, 30 and 100 µM). RT-qPCR and Western blotting were used to further explore the PI3K/AKT signaling pathway and the molecular mechanisms underlying berberine-induced inhibition of cell proliferation. Results: We demonstrated that treatment of these CRC cell lines with berberine inhibited cell proliferation, migration and invasion through induction of apoptosis and necrosis. HT-29, SW-480 and HCT-116 stained positively for AQP 1, 3 and 5, and berberine treatment down-regulated the expression of all three types of AQPs. Berberine also modulated PI3K/AKT pathway activity through up-regulating PTEN and down-regulating PI3K, AKT and p-AKT expression as well as suppressing its downstream targets, mTOR and p-mTOR at the protein level. Discussion/Conclusions: These findings indicate that berberine inhibited growth, migration and invasion of these colon cancer cell lines via down-regulation of AQP 1, 3 and 5 expressions, up-regulating PTEN which inhibited the PI3K/AKT pathway at the gene and protein levels, and that AQP 1, 3 and 5 expression level can be used as prognostic biomarkers for colon cancer metastasis.

Effect of amoxicillin/clavulanic acid in attenuating pregabalin-induced condition place preference

Substance abuse is a worldwide problem with serious repercussions for patients and the communities where they live. Pregabalin (Lyrica), is a medication commonly used to treat neuropathic pain. Like other analgesic medications there has been concern about pregabalin abuse and misuse. Although it was initially suggested that pregabalin, like other gabapentinoids, has limited abuse liability, questions still remain concerning this inquiry. Changes in glutamate system homeostasis are a hallmark of adaptations underlying drug dependence, including down-regulation of the glutamate transporter 1 (GLT-1; SLC1A2) and the cystine/glutamate antiporter (xCT; SLC7A11). In this study, it was found that pregabalin (90 mg/kg) produces a conditioned place preference (CPP), indicative of reinforcing effects that suggest a potential for abuse liability. Moreover, like other drugs of abuse, pregabalin also produced alterations in glutamate homeostasis, reducing the mRNA expression of Slc1a2 and Slc7a11 in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC). Amoxicillin clavulanic acid, a β-lactam antibiotic, blocked the reinforcing effects of pregabalin and normalized glutamate homeostasis. These results suggest that pregabalin has abuse potential that should be examined more critically, and that, moreover, the mechanisms underlying these effects are similar to those of other drugs of abuse, such as heroin and cocaine. Additionally, these results support previous findings showing normalization of glutamate homeostasis by β-lactam drugs that provides a novel potential therapeutic approach for the treatment of drug abuse and dependence.

Progress in targeting PTEN/PI3K/Akt axis in glioblastoma therapy: Revisiting molecular interactions

Glioblastoma (GBM) is one of the most malignant cancers of central nervous system and due to its sensitive location, surgical resection has high risk and therefore, chemotherapy and radiotherapy are utilized for its treatment. However, chemoresistance and radio-resistance are other problems in GBM treatment. Hence, new therapies based on genes are recommended for treatment of GBM. PTEN is a tumor-suppressor operator in cancer that inhibits PI3K/Akt/mTOR axis in diminishing growth, metastasis and drug resistance. In the current review, the function of PTEN/PI3K/Akt axis in GBM progression is evaluated. Mutation or depletion of PTEN leads to increase in GBM progression. Low expression level of PTEN mediates poor prognosis in GBM and by increasing proliferation and invasion, promotes malignancy of tumor cells. Moreover, loss of PTEN signaling can result in therapy resistance in GBM. Activation of PTEN signaling impairs GBM metabolism via glycolysis inhibition. In contrast to PTEN, PI3K/Akt signaling has oncogenic function and during tumor progression, expression level of PI3K/Akt enhances. PI3K/Akt signaling shows positive association with oncogenic pathways and its expression similar to PTEN signaling, is regulated by non-coding RNAs. PTEN upregulation and PI3K/Akt signaling inhibition by anti-cancer agents can be beneficial in interfering GBM progression. This review emphasizes on the signaling networks related to PTEN/PI3K/Akt and provides new insights for targeting this axis in effective GBM treatment.

Expression and promoter methylation of mitogen-activated protein kinase 1 in tumor and marginal cells of breast cancer

AIM

In the present study, we sought to explore potential differences in the expression and promoter methylation of mitogen-activated protein kinase 1 (MAPK1) between tumor and marginal cells of breast cancer lesions.

METHODS

A total of 50 randomly selected patients with breast cancer (BCa) undergoing needle biopsy were enrolled. Clinical specimens containing both tumor and marginal cells were collected and preserved. After DNA extraction using specific primers, MAPK1 mRNA and promoter methylation were measured with spectrophotometry at 260/280 nm absorption wavelengths. To deliver a comparative analysis, data from The Cancer Genome Atlas (TCGA) program regarding breast cancer (BRCA), were downloaded from Xena Functional Genomics Explorer and separately analyzed. The suitability of MAPK1 expression and promoter methylation as biomarkers for BCa was analyzed with receiver operating characteristic (ROC) curves.

RESULTS

We found a positive correlation between tumor stage and MAPK1 expression (P-value: 0.029) in BCa. Likewise, MAPK1 expression was significantly associated with lymph node metastasis (P-value: 0.018). There was a significant difference in the expression of MAPK1 mRNA between tumor and marginal cells of BCa and BRCA (P-value < 0.001). However, we did not find any statistically significant difference in MAPK1 promoter methylation between tumor and marginal cells of both BCa and BRCA. With an area under the curve (AUC) of 0.71, the diagnostic accuracy of MAPK1 expression in BCa and BRCA was validated. However, MAPK1 promoter methylation was not found to be a suitable biomarker.

CONCLUSION

Our findings suggest that while MAPK1 expression, might be a promising biomarker for evaluating oncogenic activity in patients suspected of BCa. We were not able to detect a prognostic/diagnostic role for MAPK1 promoter methylation.

Vitamin E TPGS-Poloxamer Nanoparticles Entrapping a Novel PI3Kα Inhibitor Potentiate Its Activity against Breast Cancer Cell Lines

N-(2-fluorphenyl)-6-chloro-4-hydroxy-2-quinolone-3-carboxamide (R19) is a newly synthesized phosphatidylinositol 3-kinase alpha (PI3Kα) inhibitor with promising activity against cancer cells. The purpose of this study was to develop a polymeric nanoparticle (NP) formulation for R19 to address its poor aqueous solubility and to facilitate its future administration in preclinical and clinical settings. NPs were prepared by nanoprecipitation using two polymers: D-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS) and the poloxamer Pluronic P123 in different ratios. Physicochemical characterization of the NPs revealed them to be around 100 nm in size with high monodispersity, a spherical morphology, and an almost neutral surface charge. The NPs achieved ~60% drug loading efficiency and sustained release of R19 for up to 96 h, with excellent colloidal stability in serum-containing cell culture media. NPs containing TPGS enhanced R19's potency against MCF-7 and MDA-MB-231 breast cancer cells in vitro, with half-maximal inhibitory concentrations (IC₅₀) ranging between 1.8 and 4.3 µM compared to free R19, which had an IC₅₀ of 14.7-17.0 µM. The NPs also demonstrated low cytotoxicity against human dermal fibroblasts and more significant induction of apoptosis compared to the free drug, which was correlated with their cellular uptake efficiency. Our findings present a biocompatible NP formulation for the delivery of a cancer-targeted PI3Kα inhibitor, R19, which can further enhance its potency for the treatment of breast cancer and potentially other cancer types.

Matrix Metalloproteinase-1 (MMP1) Upregulation through Promoter Hypomethylation Enhances Tamoxifen Resistance in Breast Cancer

Simple Summary

Cancer recurrence caused by tamoxifen resistance hampers chemotherapy in breast cancer patients. The reasons behind the resistance were investigated by screening epigenetically regulated genes through analysis of methylation data from tamoxifen-resistant MCF-7 cells. MMP1 locus was found to be hypomethylated at a promoter CpG site and its expression was upregulated in the cell line, which was verified by the drug-resistant tumor tissues from breast cancer patients (n = 28). Downregulating MMP1 using a short hairpin RNA inhibited the growth of resistant cells and increased sensitivity to tamoxifen in vitro as well as in a xenografted mouse model in vivo. This study suggests that MMP1 is potentially a target gene to control tamoxifen resistance in breast cancer.

Abstract

Background: Tamoxifen (tam) is widely used to treat estrogen-positive breast cancer. However, cancer recurrence after chemotherapy remains a major obstacle to achieve good patient prognoses. In this study, we aimed to identify genes responsible for epigenetic regulation of tam resistance in breast cancer. Methods: Methylation microarray data were analyzed to screen highly hypomethylated genes in tam resistant (tamR) breast cancer cells. Quantitative RT-PCR, Western blot analysis, and immunohistochemical staining were used to quantify expression levels of genes in cultured cells and cancer tissues. Effects of matrix metalloproteinase-1 (MMP1) expression on cancer cell growth and drug resistance were examined through colony formation assays and flow cytometry. Xenografted mice were generated to investigate the effects of MMP1 on drug resistance in vivo. Results: MMP1 was found to be hypomethylated and overexpressed in tamR MCF-7 (MCF-7/tamR) cells and in tamR breast cancer tissues. Methylation was found to be inversely associated with MMP1 expression level in breast cancer tissues, and patients with lower MMP1 expression exhibited a better prognosis for survival. Downregulating MMP1 using shRNA induced tam sensitivity in MCF-7/tamR cells along with increased apoptosis. The xenografted MCF-7/tamR cells that stably expressed short hairpin RNA (shRNA) against MMP1 exhibited retarded tumor growth compared to that in cells expressing the control shRNA, which was further suppressed by tam. Conclusions: MMP1 can be upregulated through promoter hypomethylation in tamR breast cancer, functioning as a resistance driver gene. MMP1 can be a potential target to suppress tamR to achieve better prognoses of breast cancer patients.

The mechanism of action of Fangji Huangqi Decoction on epithelial-mesenchymal transition in breast cancer using high-throughput next-generation sequencing and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Fangji Huangqi Decoction (FHD) is widely used in traditional Chinese medicine (TCM). FHD has been hypothesized to inhibit the epithelial-mesenchymal transition (EMT) process, which may positively impact breast cancer prevention and treatment. However, its exact mechanism of action is still unknown.

AIM OF THE STUDY

This study aimed to screen potential targets of FHD for the treatment of EMT in breast cancer through network pharmacology, and to verify their therapeutic effects in vitro experiments and high-throughput second-generation sequencing.

MATERIALS AND METHODS

The data sets of effective components and targets of FHD were established through the Traditional Chinese Medicine Systems Pharmacology database. The GeneCards and OMIM databases were used to establish breast cancer-related target datasets, which were then matched with the TCM target data. The interaction between key target proteins was analyzed using the STRING database; the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to identify the associated biological processes and enriched signal pathways, respectively. The active ingredient disease target network was analyzed using Cytoscape. Finally, next generation sequencing was used to verify the related pathways of FHD intervention in EMT in breast cancer. High-content screening was used to identify the genes/pathways affected by FHD. MDA-MB-231 and HCC-1937 breast cancer cell lines were used to evaluate the impact of FHD on migration, invasion, and EMT.

RESULTS

Eighty possible significant targets were identified for the treatment of breast cancer EMT with FHD; GO and KEGG were used to identify 173 cell biological processes associated with breast cancer (P < 0.05), including the NF-κB and PI3K-Akt signaling pathways. The high-throughput sequencing and network pharmacology results were highly consistent. The migration and invasion ability of MDA-MB-231 cells was reduced and their EMT status could be reversed by DSHR2 knockdown. The results of morphology and scratch assays showed that FHD could improve the EMT status of HCC-1973.

CONCLUSIONS

This study provides more evidence to support the clinical application of FHD, which has reliable interventional effects on breast cancer EMT. Its therapeutic effects may involve a multi-target, multi-pathway, and multi-mechanism effect.

Knockdown of lncRNA FOXD2-AS1 Inhibits Proliferation, Migration, and Drug Resistance of Breast Cancer Cells

OBJECTIVE

In order to investigate the effect of lncRNA FOXD2-AS1 on breast cancer cells proliferation, migration, and drug resistance as well as its molecular mechanism.

METHODS

Real-time PCR was used to detect the expression of breast cancer tissues and cells from patients admitted to our hospital and the expression of lncRNA FOXD2-AS1 in MCF-7/ADR in adriamycin- (ADR-) resistant breast cancer cells. After interfering with or overexpressing lncRNA FOXD2-AS1 in MCF-7/ADR cells, cell proliferation, apoptosis, invasion, and migration were detected using CCK-8, flow cytometry, Transwell assay, and scratch test, respectively. The protein levels of PI3K, p-PI3K, AKT, and p-AKT in the PI3K/AKT signaling pathway were detected by Western blot.

RESULTS

lncRNA FOXD2-AS1 was upregulated in breast cancer tissues and cells and increased cell drug resistance to ADR. Downregulation of lncRNA FOXD2-AS1 inhibited invasion and migration of MCF-7/ADR cells, promoted apoptosis, increased chemosensitivity of MCF-7/ADR cells, and inhibited the activity of PI3K/AKT signaling pathway in MCF-7/ADR cells.

CONCLUSIONS

lncRNA FOXD2-AS1 can promote the proliferation, invasion, migration, and drug resistance of breast cancer cells, inhibit apoptosis, and accelerate the development of breast cancer by positively regulating the PI3K/AKT signaling pathway.