PD173074, a selective FGFR inhibitor, reverses MRP7 (ABCC10)-mediated MDR

Morphogenesis and regeneration share a conserved core transition cell state program that controls lung epithelial cell fate

Transitional cell states are at the crossroads of crucial developmental and regenerative events, yet little is known about how these states emerge and influence outcomes. The alveolar and airway epithelia arise from distal lung multipotent progenitors, which undergo cell fate transitions to form these distinct compartments. The identification and impact of cell states in the developing lung are poorly understood. Here, we identified a population of Icam1/Nkx2-1 epithelial progenitors harboring a transitional state program remarkably conserved in humans and mice during lung morphogenesis and regeneration. Lineage-tracing and functional analyses reveal their role as progenitors to both airways and alveolar cells and the requirement of this transitional program to make distal lung progenitors competent to undergo airway cell fate specification. The identification of a common progenitor cell state in vastly distinct processes suggests a unified program reiteratively regulating outcomes in development and regeneration.

The role of ABCC10/MRP7 in anti-cancer drug resistance and beyond

Multidrug resistance protein 7 (MRP7), also known as ATP-binding cassette (ABC) transporter subfamily C10 (ABCC10), is an ABC transporter that was first identified in 2001. ABCC10/MRP7 is a 171 kDa protein located on the basolateral membrane of cells. ABCC10/MRP7 consists of three transmembrane domains and two nucleotide binding domains. It mediates multidrug resistance of tumor cells to a variety of anticancer drugs by increasing drug efflux and results in reducing intracellular drug accumulation. The transport substrates of ABCC10/MRP7 include antineoplastic drugs such as taxanes, vinca alkaloids, and epothilone B, as well as endobiotics such as leukotriene C4 (LTC4) and estradiol 17 β-D-glucuronide. A variety of ABCC10/MRP7 inhibitors, including cepharanthine, imatinib, erlotinib, tariquidar, and sildenafil, can reverse ABCC10/MRP7-mediated MDR. Additionally, the presence or absence of ABCC10/MRP7 is also closely related to renal tubular dysfunction, obesity, and other diseases. In this review, we discuss: 1) Structure and functions of ABCC10/MRP7; 2) Known substrates and inhibitors of ABCC10/MRP7 and their potential therapeutic applications in cancer; and 3) Role of ABCC10/MRP7 in non-cancerous diseases.

Insight into the design of FGFR4 selective inhibitors in cancer therapy: Prospects and challenges

Recently, FGFR4 has become a hot target for the treatment of cancer owing to its important role in cellular physiological processes. FGFR4 has been validated to be closely related to the occurrence of cancers, such as hepatocellular carcinoma, rhabdomyosarcoma, breast cancer and colorectal cancer. Hence, the development of FGFR4 small-molecule inhibitors is essential to further understanding the functions of FGFR4 in cancer and the treatment of FGFR4-dependent diseases. Given the particular structures of FGFR1-4, the development of FGFR4 selective inhibitors presents significant challenges. The non-conserved Cys552 in the hinge region of the FGFR4 complex becomes the key to the selectivity of FGFR4 and FGFR1/2/3 inhibitors. In this review, we systematically introduce the close relationship between FGFR4 and cancer, and conduct an in-depth analysis of the developing methodology, binding mechanism, kinase selectivity, pharmacokinetic characteristics of FGFR4 selectivity inhibitors, and their application in clinical research.

Exploring the Structural and Functional Diversity among FGF Signals: A Comparative Study of Human, Mouse, and Xenopus FGF Ligands in Embryonic Development and Cancer Pathogenesis

Fibroblast growth factors (FGFs) encode a large family of growth factor proteins that activate several intracellular signaling pathways to control diverse physiological functions. The human genome encodes 22 FGFs that share a high sequence and structural homology with those of other vertebrates. FGFs orchestrate diverse biological functions by regulating cellular differentiation, proliferation, and migration. Dysregulated FGF signaling may contribute to several pathological conditions, including cancer. Notably, FGFs exhibit wide functional diversity among different vertebrates spatiotemporally. A comparative study of FGF receptor ligands and their diverse roles in vertebrates ranging from embryonic development to pathological conditions may expand our understanding of FGF. Moreover, targeting diverse FGF signals requires knowledge regarding their structural and functional heterogeneity among vertebrates. This study summarizes the current understanding of human FGF signals and correlates them with those in mouse and Xenopus models, thereby facilitating the identification of therapeutic targets for various human disorders.

The FGFR1 Signaling Pathway Upregulates the Oncogenic Transcription Factor FOXQ1 to Promote Breast Cancer Cell Growth

FGFR1 is a receptor tyrosine kinase deregulated in certain breast cancers (BCs) with a poor prognosis. Although FGFR1-activated phosphorylation cascades have been mapped, the key genes regulated by FGFR1 in BC are largely unclear. FOXQ1 is an oncogenic transcription factor. Although we found that activation of FGFR1 robustly upregulated FOXQ1 mRNA, how FGFR1 regulates FOXQ1 gene expression and whether FOXQ1 is essential for FGFR1-stimulated cell proliferation are unknown. Herein, we confirmed that activation of FGFR1 robustly upregulated FOXQ1 mRNA and protein in BC cells. Knockdown of FOXQ1 blocked the FGFR1 signaling-stimulated BC cell proliferation, colony formation, and xenograft tumor growth. Inhibition of MEK or ERK1/2 activities, or knockout of ERK2 but not ERK1 suppressed the FGFR1 signaling-promoted FOXQ1 gene expression. Inhibition of ERK2 in ERK1 knockout cells blocked, while ectopic expression of FOXQ1 in ERK2 knockout cells rescued the FGFR1-signaling-promoted cell growth. Mechanistically, c-FOS, an early response transcription factor upregulated by the FGFR1-MEK-ERK2 pathway, bound to the FOXQ1 promoter to mediate the FGFR1 signaling-promoted FOXQ1 expression. These results indicate that the FGFR1-ERK2-c-FOS-FOXQ1 regulatory axis plays an essential role in the FGFR1 signaling-promoted BC growth. Targeting ERK2 and FOXQ1 should block BC growth caused by a deregulated FGFR1 signaling.

FGF1 protects FGFR1-overexpressing cancer cells against drugs targeting tubulin polymerization by activating AKT via two independent mechanisms

Cancer drug resistance is a common, unpredictable phenomenon that develops in many types of tumors, resulting in the poor efficacy of current anticancer therapies. One of the most common, and yet the most complex causes of drug resistance is a mechanism related to dysregulation of tumor cell signaling. Abnormal signal transduction in a cancer cell is often stimulated by growth factors and their receptors, including fibroblast growth factors (FGFs) and FGF receptors (FGFRs). Here, we investigated the effect of FGF1 and FGFR1 activity on the action of drugs that disrupt tubulin polymerization (taltobulin, paclitaxel, vincristine) in FGFR1-positive cell lines, U2OS stably transfected with FGFR1 (U2OSR1) and DMS114 cells. We observed that U2OSR1 cells exhibited reduced sensitivity to the tubulin-targeting drugs, compared to U2OS cells expressing a negligible level of FGFRs. This effect was dependent on receptor activation, as inhibition of FGFR1 by a specific small-molecule inhibitor (PD173074) increased the cells’ sensitivity to these drugs. Expression of functional FGFR1 in U2OS cells resulted in increased AKT phosphorylation, with no change in total AKT level. U2OSR1 cells also exhibited an elevated MDR1 and blocking MDR1 activity with cyclosporin A increased the toxicity of paclitaxel and vincristine, but not taltobulin. Analysis of tubulin polymerization pattern using fluorescence microscopy revealed that FGF1 in U2OSR1 cells partially reverses the drug-altered phenotype in paclitaxel- and vincristine-treated cells, but not in taltobulin-treated cells. Furthermore, we showed that FGF1, through activation of FGFR1, reduces caspase 3/7 activity and PARP cleavage, preventing apoptosis induced by tubulin-targeting drugs. Next, using specific kinase inhibitors, we investigated which signaling pathways are responsible for the FGF1-mediated reduction of taltobulin cytotoxicity. We found that AKT kinase is a key factor in FGF1-induced cell protection against taltobulin in U2OSR1 and DMS114 cells. Interestingly, only direct inhibition of AKT or dual-inhibition of PI3K and mTOR abolished this effect for cells treated with taltobulin. This suggests that both canonical (PI3K-dependent) and alternative (PI3K-independent) AKT-activating pathways may regulate FGF1/FGFR1-driven cancer cell survival. Our findings may contribute to the development of more effective therapies and may facilitate the prevention of drug resistance in FGFR1-positive cancer cells.

System analysis based on the pyroptosis-related genes identifies GSDMC as a novel therapy target for pancreatic adenocarcinoma

Background

Pancreatic adenocarcinoma (PAAD) is one of the most common malignant tumors of the digestive tract. Pyroptosis is a newly discovered programmed cell death that highly correlated with the prognosis of tumors. However, the prognostic value of pyroptosis in PAAD remains unclear.

Methods

A total of 178 pancreatic cancer PAAD samples and 167 normal samples were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. The “DESeq2” R package was used to identify differntially expressed pyroptosis-related genes between normal pancreatic samples and PAAD samples. The prognostic model was established in TCGA cohort based on univariate Cox and the least absolute shrinkage and selection operator (LASSO) Cox regression analyses, which was validated in test set from Gene Expression Omnibus (GEO) cohort. Univariate independent prognostic analysis and multivariate independent prognostic analysis were used to determine whether the risk score can be used as an independent prognostic factor to predict the clinicopathological features of PAAD patients. A nomogram was used to predict the survival probability of PAAD patients, which could help in clinical decision-making. The R package "pRRophetic" was applied to calculate the drug sensitivity of each samples from high- and low-risk group. Tumor immune infiltration was investigated using an ESTIMATE algorithm. Finally, the pro‐tumor phenotype of GSDMC was explored in PANC-1 and CFPAC-1 cells.

Result

On the basis of univariate Cox and LASSO regression analyses, we constructed a risk model with identified five pyroptosis-related genes (IL18, CASP4, NLRP1, GSDMC, and NLRP2), which was validated in the test set. The PAAD samples were divided into high-risk and low-risk groups on the basis of the risk score's median. According to Kaplan Meier curve analysis, samples from high-risk groups had worse outcomes than those from low-risk groups. The time-dependent receiver operating characteristics (ROC) analysis revealed that the risk model could predict the prognosis of PAAD accurately. A nomogram accompanied by calibration curves was presented for predicting 1-, 2-, and 3-year survival in PAAD patients. More importantly, 4 small molecular compounds (A.443654, PD.173074, Epothilone. B, Lapatinib) were identified, which might be potential drugs for the treatment of PAAD patients. Finally, the depletion of GSDMC inhibits the proliferation, invasion, and migration of pancreatic adenocarcinoma cells.

Conclusion

In this study, we developed a pyroptosis-related prognostic model based on IL18, CASP4, NLRP1, NLRP2, and GSDMC , which may be helpful for clinicians to make clinical decisions for PAAD patients and provide valuable insights for individualized treatment. Our result suggest that GSDMC may promote the proliferation and migration of PAAD cell lines. These findings may provide new insights into the roles of pyroptosis-related genes in PAAD, and offer  new therapeutic targets for the treatment of PAAD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03632-z.

Infigratinib (BGJ 398), a Pan-FGFR Inhibitor, Targets P-Glycoprotein and Increases Chemotherapeutic-Induced Mortality of Multidrug-Resistant Tumor Cells

The microtubule-targeting agents (MTAs) are well-known chemotherapeutic agents commonly used for therapy of a broad spectrum of human malignancies, exhibiting epithelial origin, including breast, lung, and prostate cancer. Despite the impressive response rates shortly after initiation of MTA-based therapy, the vast majority of human malignancies develop resistance to MTAs due to the different mechanisms. Here, we report that infigratinib (BGJ 398), a potent FGFR1-4 inhibitor, restores sensitivity of a broad spectrum of ABCB1-overexpressing cancer cells to certain chemotherapeutic agents, including paclitaxel (PTX) and doxorubicin (Dox). This was evidenced for the triple-negative breast cancer (TNBC), and gastrointestinal stromal tumor (GIST) cell lines, as well. Indeed, when MDR-overexpressing cancer cells were treated with a combination of BGJ 398 and PTX (or Dox), we observed a significant increase of apoptosis which was evidenced by an increased expression of cleaved forms of PARP, caspase-3, and increased numbers of Annexin V-positive cells, as well. Moreover, BGJ 398 used in combination with PTX significantly decreased the viability and proliferation of the resistant cancer cells. As expected, no apoptosis was found in ABCB1-overexpressing cancer cells treated with PTX, Dox, or BGJ 398 alone. Inhibition of FGFR-signaling by BGJ 398 was evidenced by the decreased expression of phosphorylated (i.e., activated) forms of FGFR and FRS-2, a well-known adaptor protein of FGFR signaling, and downstream signaling molecules (e.g., STAT-1, -3, and S6). In contrast, expression of MDR-related ABC-transporters did not change after BGJ 398 treatment, thereby suggesting an impaired function of MDR-related ABC-transporters. By using the fluorescent-labeled chemotherapeutic agent PTX-Alexa488 (Flutax-2) and doxorubicin, exhibiting an intrinsic fluorescence, we found that BGJ 398 substantially impairs their efflux from MDR-overexpressing TNBC cells. Moreover, the efflux of Calcein AM, a well-known substrate for ABCB1, was also significantly impaired in BGJ 398-treated cancer cells, thereby suggesting the ABCB1 as a novel molecular target for BGJ 398. Of note, PD 173074, a potent FGFR1 and VEGFR2 inhibitor failed to retain chemotherapeutic agents inside ABCB1-overexpressing cells. This was consistent with the inability of PD 173074 to sensitize Tx-R cancer cells to PTX and Dox. Collectively, we show here for the first time that BGJ 398 reverses the sensitivity of MDR-overexpressing cancer cells to certain chemotherapeutic agents due to inhibition of their efflux from cancer cells via ABCB1-mediated mechanism.

FGF/FGFR-Dependent Molecular Mechanisms Underlying Anti-Cancer Drug Resistance

Simple Summary

Deregulation of the FGF/FGFR axis is associated with many types of cancer and contributes to the development of chemoresistance, limiting the effectiveness of current treatment strategies. There are several mechanisms involved in this phenomenon, including cross-talks with other signaling pathways, avoidance of apoptosis, stimulation of angiogenesis, and initiation of EMT. Here, we provide an overview of current research and approaches focusing on targeting components of the FGFR/FGF signaling module to overcome drug resistance during anti-cancer therapy.

Abstract

Increased expression of both FGF proteins and their receptors observed in many cancers is often associated with the development of chemoresistance, limiting the effectiveness of currently used anti-cancer therapies. Malfunctioning of the FGF/FGFR axis in cancer cells generates a number of molecular mechanisms that may affect the sensitivity of tumors to the applied drugs. Of key importance is the deregulation of cell signaling, which can lead to increased cell proliferation, survival, and motility, and ultimately to malignancy. Signaling pathways activated by FGFRs inhibit apoptosis, reducing the cytotoxic effect of some anti-cancer drugs. FGFRs-dependent signaling may also initiate angiogenesis and EMT, which facilitates metastasis and also correlates with drug resistance. Therefore, treatment strategies based on FGF/FGFR inhibition (using receptor inhibitors, ligand traps, monoclonal antibodies, or microRNAs) appear to be extremely promising. However, this approach may lead to further development of resistance through acquisition of specific mutations, metabolism switching, and molecular cross-talks. This review brings together information on the mechanisms underlying the involvement of the FGF/FGFR axis in the generation of drug resistance in cancer and highlights the need for further research to overcome this serious problem with novel therapeutic strategies.

Insights on the structure-function relationship of human multidrug resistance protein 7 (MRP7/ABCC10) from molecular dynamics simulations and docking studies

ATP-binding cassette (ABC) transporters superfamily mediates multidrug resistance in cancer by extruding structurally distinct chemotherapeutic agents, causing failure in chemotherapy. Among the 49 ABC transporters, multidrug resistance protein 7 (MRP7 or ABCC10) is relatively new and has been identified as the efflux pump of multiple anticancer agents including Vinca alkaloids and taxanes. Herein, we construct and validate a homology model for human MRP7 based on the cryo-EM structures of MRP1. Structure-function relationship of MRP7 was obtained from molecular dynamics simulations and docking studies and was in accordance with previous studies of ABC transporters. The motion patterns correlated with efflux mechanism were discussed. Additionally, predicted substrate- and modulator-binding sites of MRP7 were described for the first time, which provided rational insights in understanding the drug binding and functional regulation in MRP7. Our findings will benefit the high-throughput virtual screening and development of MRP7 modulators in the future.

Establishment and Characterization of a Novel Multidrug Resistant Human Ovarian Cancer Cell Line With Heterogenous MRP7 Overexpression

Ovarian cancer is one of the leading female malignancies which accounts for the highest mortality rate among gynecologic cancers. Surgical cytoreduction followed by chemotherapy is the mainstay of treatment. However, patients with recurrent ovarian cancer are likely to exhibit resistance to chemotherapy due to reduced sensitivity to chemotherapeutic drugs. Adenosine triphosphate (ATP)-binding cassette (ABC) transporters have been extensively studied as multidrug resistance (MDR) mediators since they are responsible for the efflux of various anticancer drugs. Multidrug resistance protein 7 (MRP7, or ABCC10) was discovered in 2001 and revealed to transport chemotherapeutic drugs. Till now, only limited knowledge was obtained regarding its roles in ovarian cancer. In this study, we established an MRP7-overexpressing ovarian cancer cell line SKOV3/MRP7 via transfecting recombinant MRP7 plasmids. The SKOV3/MRP7 cell line was resistant to multiple anticancer drugs including paclitaxel, docetaxel, vincristine and vinorelbine with a maximum of 8-fold resistance. Biological function of MRP7 protein was further determined by efflux-accumulation assays. Additionally, MTT results showed that the drug resistance of the SKOV3/MRP7 cells was reversed by cepharanthine, a known inhibitor of MRP7. Moreover, we also found that the overexpression of MRP7 enhanced the migration and epithelial-mesenchymal transition (EMT) induction. In conclusion, we established an in vitro model of MDR in ovarian cancer and suggested MRP7 overexpression as the leading mechanism of chemoresistance in this cell line. Our results demonstrated the potential relationship between MRP7 and ovarian cancer MDR.

Drug resistance: from bacteria to cancer

The phenomenon of drug resistance has been a hindrance to therapeutic medicine since the late 1940s. There is a plethora of factors and mechanisms contributing to progression of drug resistance. From prokaryotes to complex cancers, drug resistance is a prevailing issue in clinical medicine. Although there are numerous factors causing and influencing the phenomenon of drug resistance, cellular transporters contribute to a noticeable majority. Efflux transporters form a huge family of proteins and are found in a vast number of species spanning from prokaryotes to complex organisms such as humans. During the last couple of decades, various approaches in analyses of biochemistry and pharmacology of transporters have led us to understand much more about drug resistance. In this review, we have discussed the structure, function, potential causes, and mechanisms of multidrug resistance in bacteria as well as cancers.

Enhancement of anticancer drug sensitivity in multidrug resistance cells overexpressing ATP-binding cassette (ABC) transporter ABCC10 by CP55, a synthetic derivative of 5-cyano-6-phenylpyrimidin

ATP-binding cassette (ABC) transporter C10 (ABCC10), also named multidrug resistance protein 7 (MRP7), is a member of ABC transporter superfamily and has been revealed to transport a wide range of chemotherapeutic agents including taxanes, epothilone B, Vinca alkaloids, and anthracyclines. In our previous study, a 5-cyano-6-phenylpyrimidin derivative CP55 was synthesized and found significantly reversal effect of multidrug resistance (MDR) mediated by ABCB1. In this study, we found CP55 also efficiently reversed MDR mediated by ABCC10. Our in vitro study showed that co-treatment with CP55 significantly increased the efficacy of ABCC10-substrate anticancer drugs in MDR cells overexpressing ABCC10. Furthermore, we showed that treatment with CP55 increased the intracellular accumulation of [³H]-labeled anticancer drugs and in-turn decreasing drug efflux by inhibiting the transport activity, without altering ABCC10 protein ex-pression level or cellular localization. Potential CP55-ABCC10 interactions were predicted via docking analysis using human ABCC10 homology model and obtained high docking score. Therefore, CP55 represents a promising therapeutic agent in the combinational treatment of chemo-resistant cancer related to ABCC10.

CMP25, a synthetic new agent, targets multidrug resistance-associated protein 7 (MRP7/ABCC10)

Multidrug resistance-associated protein 7 (MRP7) is an important member of ABC transporter superfamily and has been revealed to mediate the cross-membrane translocation of a wide range of chemotherapeutic agents including taxanes, epothilones, Vinca alkaloids, Anthracyclines and Epipodophyllotoxins.In our previous study, a 1,2,3-triazole-pyrimidine hybridCMP25was synthesized and found able to efficiently reverse multidrug resistance (MDR) mediated by P-glycoprotein. In this study, we evaluated the efficacy of compound CMP25in reversing MDR mediated by MRP7in vitro. The results showed that CMP25significantly sensitized MRP7-overexpressing cells to anticancer drugs that are MRP7 substrates. Mechanistic study showed that CMP25reversed MRP7-mediated MDR by increasing the intracellular accumulation of anticancer drugs and decreasing drug efflux, without altering protein expression level or subcellular localization. Currently, very few studies on synthetic MRP7 modulators have been published. Our findings provide a valuable prototype for designing drugs to combine with conventional anticancer drugs to overcome MDR-mediated by MRP7.

Multidrug resistance proteins (MRPs): Structure, function and the overcoming of cancer multidrug resistance

ATP-binding cassette (ABC) transporters mediate the ATP-driven translocation of structurally and mechanistically distinct substrates against steep concentration gradients. Among the seven human ABC subfamilies namely ABCA-ABCG, ABCC is the largest subfamily with 13 members. In this respect, 9 of the ABCC members are termed "multidrug resistance proteins" (MRPs1-9) due to their ability to mediate cancer multidrug resistance (MDR) by extruding various chemotherapeutic agents or their metabolites from tumor cells. Furthermore, MRPs are also responsible for the ATP-driven efflux of physiologically important organic anions such as leukotriene C₄, folic acid, bile acids and cAMP. Thus, MRPs are involved in important regulatory pathways. Blocking the anticancer drug efflux function of MRPs has shown promising results in overcoming cancer MDR. As a result, many novel MRP modulators have been developed in the past decade. In the current review, we summarize the structure, tissue distribution, biological and pharmacological functions as well as clinical insights of MRPs. Furthermore, recent updates in MRP modulators and their therapeutic applications in clinical trials are also discussed.

miR-361 enhances sensitivity to 5-fluorouracil by targeting the FOXM1-ABCC5/10 signaling pathway in colorectal cancer

Colorectal cancer (CRC) is one of most common malignancies worldwide. 5-fluorouracil (5-FU) is a mainstay of CRC treatment, particularly in patients with advanced stages of the disease; however, 5-FU-based chemotherapy is not always effective and may result in progression of the disease. The present study investigated several candidate microRNAs (miRs) in parental and 5-FU-resistant HCT116 and HT29 cells, and identified miR-361 as a novel regulator of chemosensitivity. Overexpression of miR-361 enhanced the 5-FU susceptibility of parental and resistant HCT116 and HT29 cells in vitro. Impaired colony formation capacity and increased cell apoptosis (as determined via flow cytometry) was observed in resistant HCT116 and HT29 cells. Furthermore, forkhead box M1 (FOXM1) was identified as a target gene of miR-361 using a dual-luciferase reporter assay, western blotting and reverse transcription-quantitative PCR. Additionally, FOXM1 knockdown improved the cytotoxicity of 5-FU in resistant CRC. ATP binding cassette subfamily C members 5 and 10 (ABCC5/10) were found to be downstream effectors of miR-361. In conclusion, miR-361 increased chemosensitivity, at least in part, via modulation of FOXM1-ABCC5/10. miR-361 may serve as a potential therapeutic target for patients with CRC.

Genomics of drug sensitivity in bladder cancer: an integrated resource for pharmacogenomic analysis in bladder cancer

Background

Bladder cancer has numerous genomic features that are potentially actionable by targeted agents. Nevertheless, both pre-clinical and clinical research using molecular targeted agents have been very limited in bladder cancer.

Results

We created the Genomics of Drug Sensitivity in Bladder Cancer (GDBC) database, an integrated database (DB) to facilitate the genomic understanding of bladder cancer in relation to drug sensitivity, in order to promote potential therapeutic applications of targeted agents in bladder cancer treatment. The GDBC database contains two separate datasets: 1) in-house drug sensitivity data, in which 13 targeted agents were tested against 10 bladder cancer cell lines; 2) data extracted and integrated from public databases, including the Cancer Therapeutics Research Portal, Cancer Cell Line Encyclopedia, Genomics of Drug Sensitivity in Cancer, Kyoto Encyclopedia of Genes and Genomes, and the Cancer Gene Census databases, as well as bladder cancer genomics data and synthetic lethality/synthetic dosage lethality connections.

Conclusions

GDBC is an integrated DB of genomics and drug sensitivity data with a specific focus on bladder cancer. With a user-friendly web-interface, GDBC helps users generate genomics-based hypotheses that can be tested experimentally using drugs and cell lines included in GDBC.

Electronic supplementary material

The online version of this article (10.1186/s12920-018-0406-2) contains supplementary material, which is available to authorized users.

TNFAIP3 is required for FGFR1 activation-promoted proliferation and tumorigenesis of premalignant DCIS.COM human mammary epithelial cells

BACKGROUND

Although ductal carcinoma in situ (DCIS) is a non-invasive breast cancer, many DCIS lesions may progress to invasive cancer and the genes and pathways responsible for its progression are largely unknown. FGFR1 plays an important role in cell proliferation, differentiation and carcinogenesis. The purpose of this study is to examine the roles of FGFR1 signaling in gene expression, cell proliferation, tumor growth and progression in a non-invasive DCIS model.

METHODS

DCIS.COM cells were transfected with an empty vector to generate DCIS-Ctrl cells. DCIS-iFGFR1 cells were transfected with an AP20187-inducible iFGFR1 vector to generate DCIS-iFGFR1 cells. iFGFR1 consists of the v-Src myristoylation membrane-targeting sequence, FGFR1 cytoplasmic domain and the AP20187-inducible FKBP12 dimerization domain, which simulates FGFR1 signaling. The CRISPR/Cas9 system was employed to knockout ERK1, ERK2 or TNFAIP3 in DCIS-iFGFR1 cells. Established cell lines were treated with/without AP20187 and with/without FGFR1, MEK, or ERK1/2 inhibitor. The effects of these treatments were determined by Western blot, RNA-Seq, real-time RT-PCR, cell proliferation, mammosphere growth, xenograft tumor growth, and tumor histopathological assays.

RESULTS

Activation of iFGFR1 signaling in DCIS-iFGFR1 cells enhanced ERK1/2 activities, induced partial epithelial-to-mesenchymal transition (EMT) and increased cell proliferation. Activation of iFGFR1 signaling promoted DCIS growth and progression to invasive cancer derived from DCIS-iFGFR1 cells in mice. Activation of iFGFR1 signaling also altered expression levels of 946 genes involved in cell proliferation, migration, cancer pathways, and other molecular and cellular functions. TNFAIP3, a ubiquitin-editing enzyme, is upregulated by iFGFR1 signaling in a FGFR1 kinase activity and in an ERK2-dependent manner. Importantly, TNFAIP3 knockout not only inhibited the AP20187-induced proliferation and tumor growth of DCIS-iFGFR1 cells, but also further reduced baseline proliferation and tumor growth of DCIS-iFGFR1 cells without AP20187 treatment.

CONCLUSIONS

Activation of iFGFR1 promotes ERK1/2 activity, EMT, cell proliferation, tumor growth, DCIS progression to invasive cancer, and altered the gene expression profile of DCIS-iFGFR1 cells. Activation of iFGFR1 upregulated TNFAIP3 in an ERK2-dependent manner and TNFAIP3 is required for iFGFR1 activation-promoted DCIS.COM cell proliferation, mammosphere growth, tumor growth and progression. These results suggest that TNFAIP3 may be a potential target for inhibiting DCIS growth and progression promoted by FGFR1 signaling.

The therapeutic targeting of the FGFR1/Src/NF-κB signaling axis inhibits pancreatic ductal adenocarcinoma stemness and oncogenicity

The aberrant activation of the FGFR signaling is detected in many solid tumors, including pancreatic ductal adenocarcinoma (PDAC), suggesting it as a potential therapeutic target. In this study, we investigated the antitumor and anti-metastasis efficacy of the selective FGFR1 inhibitor, PD173074 in PDAC. We used immunohistochemical and in situ hybridization analyses to demonstrate a strong correlation between FGFR1 amplification and/or expression and disease progression in PDAC patients. We showed that ALDH^high (ALDH+) pancreatic cancer cells exhibited stem cell-like phenotype and expressed higher levels of FGFR1, Src, NF-κB, alongside stemness markers like Oct4 and Sox2, compared to their ALDH^low/null (ALDH-) counterparts, suggesting the preferential activation of the FGFR1/Src/NF-κB signaling axis in pancreatic cancer stem cells (panCSCs). Furthermore, treatment of the ALDH^high/ FGFR1-rich pancreatic cancer cell lines with PD173074, a selective FGFR1 inhibitor, revealed that PD173074 inhibited the proliferation and self-renewal of the panCSCs, and induced their apoptosis by activating caspase-3 and cleaving Poly-ADP ribose Polymerase (PARP). The anti-CSCs effect of PD173074 was associated with decreased expression of Oct4, Sox-2, Nanog, and c-Myc, as well as suppression of XIAP, Bcl2, and survivin expression, dose-dependently. Additionally, activation of cMet, Src, ERK 1/2 and NFκB (p65) was also inhibited by PD173074. Also, of clinical relevance, the disruption of the FGFR1/Src/NF-κB signaling axis positively correlated with poor clinical prognosis among the PDAC patients. We concluded that PD173074 suppresses the tumorigenesis and CSCs-like phenotype of PDAC cells, highlighting its therapeutic efficacy and providing support for its potential use as a therapeutic option for the 'difficult-to-treat', 'quick-to-relapse' PDAC patients. Schematic abstract showing how PD173074 inhibits PDAC growth through selective targeting of FGFR1, suppression of cancer stemness, disruption of the FGFR1/Src/NF-κB signaling axis and activation of the cell death signaling pathway.

Tyrosine kinase inhibitors enhanced the efficacy of conventional chemotherapeutic agent in multidrug resistant cancer cells

Multidrug resistance (MDR) triggered by ATP binding cassette (ABC) transporter such as ABCB1, ABCC1, ABCG2 limited successful cancer chemotherapy. Unfortunately, no commercial available MDR modulator approved by FDA was used in clinic. Tyrosine kinase inhibitors (TKIs) have been administrated to fight against cancer for decades. Almost TKI was used alone in clinic. However, drug combinations acting synergistically to kill cancer cells have become increasingly important in cancer chemotherapy as an approach for the recurrent resistant disease. Here, we summarize the effect of TKIs on enhancing the efficacy of conventional chemotherapeutic drug in ABC transporter-mediated MDR cancer cells, which encourage to further discuss and study in clinic.

Hurdles in selection process of nanodelivery systems for multidrug-resistant cancer

PURPOSE

Most of the nanomedicines for treatment of multidrug-resistant cancer do not reach Phase III trials and many are terminated or withdrawn or are in an indeterminate state since long without any study results being presented. Extensive perusal of nanomedicine development research revealed that one of the critical aspects influencing clinical outcomes and which requires diligent scrutiny is selection process of nanodelivery system.

METHODS

Research papers and articles published on development of nanodelivery systems for treatment of multidrug-resistant cancer were analyzed. Observations and conclusions noted by these researchers which might shed some light on poor clinical performance of nanocarriers were collated and summarized under observation section. Further research articles were studied to find possible solutions which may be applied to these particular problems for resolving them. The inferences of these findings were composed in Result section.

RESULT

Plausible solutions for the observed obstacles were noted as examples of novel formulations that can yield the following: better in vivo imaging, precise targeting and dosing of a specific site and specific cell type in a particular cancer, modulation of tumor surroundings, intonation of systemic effects and high reproducibility.

CONCLUSION

The angle of approach to the development of best nanosystem for a specific type of tumor needs to be spun around. Some of these changes can be brought about by individual scientists, some need to be established by collated efforts of scientists globally and some await advent of better technologies. Regardless of the stratagem, it can be said decisively that the schematics of development phase need rethinking.

Tyrosine kinase inhibitors as reversal agents for ABC transporter mediated drug resistance

Tyrosine kinases (TKs) play an important role in pathways that regulate cancer cell proliferation, apoptosis, angiogenesis and metastasis. Aberrant activity of TKs has been implicated in several types of cancers. In recent years, tyrosine kinase inhibitors (TKIs) have been developed to interfere with the activity of deregulated kinases. These TKIs are remarkably effective in the treatment of various human cancers including head and neck, gastric, prostate and breast cancer and several types of leukemia. However, these TKIs are transported out of the cell by ATP-binding cassette (ABC) transporters, resulting in development of a characteristic drug resistance phenotype in cancer patients. Interestingly, some of these TKIs also inhibit the ABC transporter mediated multi drug resistance (MDR) thereby; enhancing the efficacy of conventional chemotherapeutic drugs. This review discusses the clinically relevant TKIs and their interaction with ABC drug transporters in modulating MDR.