scholarly journals Dissecting targeted therapy resistance: Integrating models to quantify environment mediated drug resistance

2017 ◽  
Author(s):  
Noemi Picco ◽  
Erik Sahai ◽  
Philip K. Maini ◽  
Alexander R. A. Anderson
Keyword(s):  
Drug Resistance ◽  
Targeted Therapy ◽  
Targeted Therapies ◽  
Carrying Capacity ◽  
Conflicts Of Interest ◽  
Treatment Strategies ◽  
Model Systems ◽  
Significant Heterogeneity

AbstractDrug resistance is the single most important driver of cancer treatment failure for modern targeted therapies. This resistance may be due to the presence of dormant or aggressive tumor cell phenotypes or to context-driven protection. Non-malignant cells and other factors, constituting the microenvironment in which the tumor grows (the stroma), are now thought to play a crucial role in both therapeutic response and resistance. Specifically, the dialogue between the tumor and stroma has been shown to modulate the response to molecularly targeted therapies, through proliferative and survival signaling. The goal of this work is to investigate interactions between a growing tumor and its surrounding stroma in facilitating the emergence of drug resistance. We use mathematical modeling as a theoretical framework to bridge between experimental models and scales, with the aim of separating the intrinsic and extrinsic components of resistance in BRAF mutated melanoma. The model describes tumor-stroma dynamics both with and without treatment. Calibration of our model, through the integration of experimental data, revealed significant variation across animal replicates in either the intensity of stromal promotion or intrinsic tissue carrying capacity. Furthermore our study highlights the need to account for this variation in the design of treatment strategies. Major Findings. Through the integration of a simple mathematical model with in vitro and in vivo experimental growth dynamics of melanoma cell lines (both with and without drug), we were able to dissect the relative contributions of intrinsic versus environmental resistance. Our study revealed significant heterogeneity in vivo, indicating that there is a diversity of either stromal promotion or tumor carrying capacity under targeted therapy. We believe this variation may be one possible explanation for the heterogeneity observed across patients and within individual patients with multiple metastases. Therefore, quantifying this variation both within in vivo model systems and in individual patients could have a significant impact on the design of future treatment strategies that target both the tumor and stroma. Further, we present guidelines for building more effective and longer lasting therapeutic strategies utilizing our experimentally calibrated model. These strategies explicitly consider the protective nature of the stroma and utilize inhibitors that modulate it.PrecisQuantification of the environmental contribution to drug resistance reveals heterogeneity that significantly alters treatment dynamics that can be exploited for therapeutic gain.Financial SupportPicco and Anderson: US National Cancer Institute grant U01CA151924.Picco: UK Engineering and Physical Sciences Research Council (EPSRC grant number EP/G037280/1).Conflict of Interest DisclosureThe authors declare no potential conflicts of interest.

Investigating the Expression of the MRD Marker CD58 on Leukaemia Initiating Cells in Childhood Acute Lymphoblastic Leukaemia

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1887-1887 ◽  
Author(s):  
Charlotte Victoria Cox ◽  
Paraskevi Diamanti ◽  
Allison Blair
Keyword(s):  
Acute Lymphoblastic Leukaemia ◽  
Lymphoblastic Leukaemia ◽  
Conflicts Of Interest ◽  
Residual Disease ◽  
Model Systems ◽  
Childhood All ◽  
Therapy Assessment ◽  
Childhood Acute Lymphoblastic Leukaemia

Abstract Abstract 1887 Further improvements in outcome for childhood acute lymphoblastic leukaemia (ALL) will require a better understanding of the underlying biology of this disease and the fundamental mechanisms of drug resistance. The discoveries that a few populations can initiate leukemia in mouse models and that new populations of leukaemia initiating cells (LIC) can be detected following an initial round of transplantation in these models raises important questions about the biology of the leukaemias. If several cell populations have LIC properties, what are the relationships of these populations to each other and which populations are most important to target with therapy? It will also be important to determine whether there is any correlation in the biological properties of LIC identified in the model systems with the response of the patients to therapy. Assessment of minimal residual disease (MRD) levels provides a sensitive measurement of early treatment response and permits detection of the in vivo selected drug resistant population. CD58 (leucocyte function-associated antigen 3; LFA-3) is a useful marker in MRD tracking of B cell precursor (BCP) ALL. CD58 is over expressed in these cases permitting discrimination of leukaemia blasts from normal B cells. In this study we investigated whether CD58 is expressed on LIC populations in childhood ALL. Expression of CD58 and CD34 was assessed in a cohort of 12 diagnostic samples with mixed prognoses and compared to levels detected in 11 normal bone marrow (NBM) samples. Levels of CD58 were significantly higher in the ALL cases (57.4±37.7%) than on NBM cells (21.1±12.2%; p=0.007). Likewise, the CD34+/CD58+ population was larger in ALL cases than in normal cells (22.2±34.7% and 0.25±0.25%, respectively; p=0.05). Cells from eight of the 12 patients, were sorted on the basis of expression or lack of expression of these markers and the functional ability of the sorted subpopulations was assessed in vitro and in vivo. On sorting, the majority of cells were CD34−/CD58− (43.7±39.2%), 20.7±30.7% were CD34−/CD58+, 19±14.3% were CD34+/CD58+ and the CD34+/CD58− population accounted for 16.6±35.3%. Unsorted cells and all 4 sorted populations were set up in long-term culture to assess proliferative capability and the in vivo propagating potential was assessed in NSG mice. All 4 sorted subpopulations proliferated over the 6 week period but the highest levels of expansion were observed in the cultures of CD34+/CD58+ (6–420 fold) and CD34+/CD58− (3–24 fold) cells. Cytogenetic analyses confirmed that leukaemia cells were maintained in the culture system. Results from the in vivo analyses on 5 cases to date indicate that all 4 subpopulations contain LIC. In these cases, higher levels of engraftment were observed with CD34+/CD58+ (up to 20%) and with CD34−/CD58− subpopulations (6.1-98%). Serial transplantation studies will determine whether there are differences in the repopulating and self-renewal abilities of these LIC. These findings suggest that using CD58 alone or in combination with CD34 would be insufficient to track disease progression in ALL. Incorporating additional markers that are commonly used in MRD panels will provide valuable information on LIC populations and facilitate development of improved disease monitoring. Disclosures: No relevant conflicts of interest to declare.

Somatic Mutational Landscape of AML with Inv(16) and t(8;21) Identifies Two Distinct Patterns in Relapse Tumors

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2362-2362
Author(s):  
Raman B. Sood ◽  
Nancy F Hansen ◽  
Frank X Donovan ◽  
Blake Carrington ◽  
Baishali Maskeri ◽  
...  
Keyword(s):  
Conflicts Of Interest ◽  
Clonal Evolution ◽  
Treatment Strategies ◽  
Gene Mutations ◽  
Driver Gene ◽  
Intrinsic Resistance ◽  
Driver Genes ◽  
In Vivo Models

Abstract Acute myeloid leukemia (AML) is a heterogeneous disease with a wide prognostic spectrum ranging from poor to good depending upon the underlying mutations and/or cytogenetic abnormalities. Although AMLs with inv(16)/t(16:16) or t(8,21), collectively referred to as core binding factor leukemias (CBF-AMLs), are classified as prognostically favorable, such patients often succumb to their disease following relapse after an initial response to cytarabine/anthracyclin-based treatment regimens. Thus, to develop successful treatment strategies, it is critical to understand the mechanisms leading to disease relapse and target them with novel therapeutic approaches. To pursue this goal, we applied genomic approaches (whole exome sequencing and single nucleotide polymorphism arrays) on DNA from samples collected at sequential time points (i.e., diagnosis, complete remission and relapse) in seven patients with inv(16) and six patients with t(8;21). We identified mutations in several previously identified AML driver genes, such as KIT, FLT3, DNMT3A, EZH2, SMC1A, SMC3, WT1 and NRAS. Three relapse samples showed mosaicism for monosomy/disomy of the region of chromosome 3 containing GATA2. Overall, our data revealed two distinct profiles that support different mechanisms of relapse: 1) diagnosis and relapse blasts harbor the same driver gene mutations, indicating the intrinsic resistance of the major clones present at diagnosis to treatment regimen used; 2) diagnosis and relapse tumors have different driver gene mutations, indicating disease clonal evolution possibly through treatment selective pressure. Furthermore, our data has identified previously unreported putative driver genes for AML. Among these, we identified same somatic variant (R222G) in DHX15, an RNA helicase involved in splicing, in two patients at diagnosis. The variant was also detected at relapse in one of these patients. Functional validation of the mechanistic roles of wild type and mutated DHX15 in hematopoiesis and leukemogenesis, respectively, is ongoing in in vitro and in vivo models. Disclosures No relevant conflicts of interest to declare.

A Whole Genome In Vivo Crispr Screen in Primary ALL Predicts Leukaemic Relapse

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2619-2619
Author(s):  
Katherine Dormon ◽  
Elda S Latif ◽  
Matthew Bashton ◽  
Deepali Pal ◽  
Matthew Selby ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Conflicts Of Interest ◽  
Gene Set Enrichment Analysis ◽  
Whole Genome ◽  
Competitive Situation ◽  
Nsg Mice ◽  
A Genome ◽  
Crispr Screen

Abstract Although paediatric acute lymphoblastic leukaemia (ALL) has a favourable prognosis, a number of cases will invariably relapse. One of the major problems associated with relapse is drug resistance, in particular to glucocorticoids, the mainstay of ALL treatment. Examining the underlying mechanisms is complicated by clonal heterogeneity within a patient and the potential impact of the leukaemic niche. To address mechanisms of drug resistance in a patient-relevant setting, we performed a genome-wide in vivo CRISPR screen in primary ALL material. To that end, we took advantage of primografted material from patient L707, who initially presented with a Dexamethasone (DEX) sensitive t(17;19) ALL, but relapsed 5 months after initial diagnosis. We transduced DEX sensitive presentation cells with the full genome GeCKOv2 CRISPR library, before transplantation into immunodeficient NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice. Mice were subsequently treated with DEX by oral gavage (15mg/kg for 5 weeks, 10mg/kg thereafter). DNA from several engrafted sites in the mouse was extracted and PCR amplified before being sequenced on the Illumina HiSeq2500. Changes in pool complexity were analysed using MaGEcK software to determine which sgRNAs were significantly enriched or depleted. By far the most significantly enriched sgRNAs were those targeting NR3C1, the gene encoding the glucocorticoid receptor. In addition, two of the top five significantly depleted sgRNAs targeted the Plexins, PLXNA1 and PLXND1. Whilst PLXNA1 is expressed at low levels, PLXND1 is highly expressed and has been linked to dexamethasone resistance. Notably, the matched relapsed material from L707 was highly DEX resistant both in tissue culture and when transplanted into NSG mice. SNP 6.0 analysis revealed a 5q deletion in the relapse, spanning 5 genes including NR3C1. Whole genome sequencing showed this was comprised of 2 deletions both targeting NR3C1, with different breakpoints for each allele. The differential gene expression between the L707 presentation and relapse established that NR3C1 was the most significant of all the genes lost at relapse, based on gene set enrichment analysis (GSEA). This contrasts with many ALL cases, where one of the downstream effectors of apoptosis is lost as opposed to NR3C1. Growth of the relapse material in vivo and in vitro was slower than the presentation in a competitive situation, but with DEX treatment the relapse phenotype began to emerge with a small percentage of cells showing a heterozygous deletion of NR3C1. These combined data strongly suggest that the NR3C1 deletion is the main driver of DEX resistance in the L707 relapse. Moreover, it proves that our in vivo CRISPR screen predicted the leukaemic relapse. These results confirm NR3C1 deletion as a driver in glucocorticoid resistance and demonstrate the power of in vivo CRISPR screens to predict mechanisms of gain of drug resistance and subsequent relapse. The parallels that can be drawn between the relapse and the CRISPR screen are striking, giving the indication that the progression from presentation to relapse may follow the same path in a patient derived xenograft setting as it did in the patient. Disclosures No relevant conflicts of interest to declare.

scholarly journals Loss of PI3 kinase association improves the sensitivity of secondary mutation of KIT to Imatinib

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Guangrong Zhu ◽  
Jun Shi ◽  
Shaoting Zhang ◽  
Yue Guo ◽  
Ling Huang ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Targeted Therapy ◽  
Kinase Activity ◽  
Cell Transformation ◽  
Pi3 Kinase ◽  
Driver Mutations ◽  
Secondary Mutation ◽  
Lipid Kinase

Abstract Background KIT mutations are the predominant driver mutations in gastrointestinal stromal tumors (GISTs), and targeted therapy against KIT has improved treatment outcome dramatically. However, gaining secondary mutation of KIT confers drug resistance of GISTs leading to treatment failure. Results In this study, we found that secondary mutation of KIT dramatically increases the ligand-independent activation of the receptor and their resistance to the often used KIT inhibitor Imatinib in the treatment of GISTs. PI3 kinase plays essential roles in the cell transformation mediated by the primary mutation of KIT. We found that loss of PI3 kinase association, but not the inhibition of the lipid kinase activity of PI3 kinase, inhibits the ligand-independent activation of secondary mutations of KIT, and increases their sensitivity to Imatinib, and loss of PI3 kinase association inhibits secondary mutations of KIT mediated cell survival and proliferation in vitro. The in vivo assay further showed that the growth of tumors carrying secondary mutations of KIT is more sensitive to Imatinib when PI3 kinase association is blocked while inhibition of the lipid kinase activity of PI3 kinase cannot inhibit tumor growth, indicating that PI3 kinase is important for the drug resistance of secondary mutation of KIT independent of the lipid kinase activity of PI3 kinase. Conclusions Our results suggested that PI3 kinase is necessary for the ligand-independent activation of secondary mutations of KIT, and loss of PI3 kinase association improves the sensitivity of secondary mutations to the targeted therapy independent of the lipid kinase activity of PI3 kinase.

RFWD2 Induces Cellular Proliferation and Proteasome Inhibitor Resistance By Mediating p27 Ubiqutinaiton in Multiple Myeloma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3068-3068
Author(s):  
Ye Yang ◽  
Mengjie Guo ◽  
Chunyan Gu
Keyword(s):  
Multiple Myeloma ◽  
Cell Proliferation ◽  
Drug Resistance ◽  
Proteasome Inhibitor ◽  
Cellular Proliferation ◽  
Conflicts Of Interest ◽  
Scid Mice ◽  
Rpmi 8226

Purpose: In recent years, with the emergence of targeted proteasome inhibitors (PIs), the treatment of multiple myeloma (MM) has made great progress and significantly improves the survival rate of patients. However, MM remains an incurable disease, mainly due to the recurrence of drug resistance. The constitutive photomorphogenic 1 (RFWD2, also known as COP1), is closely related to the occurrence and development of tumors, but its role in MM is largely unknown. This study was aimed to explore the mechanism of RFWD2 on cell proliferation and resistance to proteasome inhibitor in MM. Experimental Design: Using gene expression profiling (GEP) samples, we verified the relation of RFWD2 to MM patients' survival and drug-resistance. The effect of RFWD2 on cell proliferation was confirmed by MTT and cell cycle analysis in RFWD2-overexpressed and RFWD2-knockdown MM cells. MTT and apoptosis experiments were performed to evaluate whether RFWD2 influenced the sensitivity of MM cells to several chemotherapy drugs. MM xenografts were established in immunodeficient NOD/SCID mice by injecting wild-type or RFWD2 over-expression MM cells with drug intervention. The mechanism of drug resistance was elucidated by analyzing the association of RFWD2 with E3 ligase of p27. Bortezomib-resistant RPMI 8226 cells were used to construct RFWD2 knockdown cells, which were injected into NOD/SCID mice to assess the effect of RFWD2 on bortezomib resistance in vivo. Results: RFWD2 expression was closely related to poor outcome, relapse and bortezomib resistance in MM patients' GEP cohorts. Elevated RFWD2 induced cell proliferation, while decreased RFWD2 inhibited cell proliferation and induced apoptosis in MM cells. RFWD2-overexpression MM cells resulted in PIs resistance, however, no chemotherapy resistance to adriamycin and dexamethasone was observed in vitro. In addition, overexpressing RFWD2 in MM cells led to bortezomib resistance rather than adriamycin resistance in myeloma xenograft mouse model. RFWD2 regulated the ubiquitination degradation of P27 by interacting with RCHY1 ubiquitin ligase. The knockdown of RFWD2 in bortezomib-resistant RPMI 8226 cells overcame bortezomib resistance in vivo. Conclusions: Our data demonstrate that elevated RFWD2 induces MM cell proliferation and resistance to PIs, but not to adriamycin and dexamethasone both in vitro and in vivo through mediating the ubiquitination of p27. Collectively, RFWD2 is a novel promising therapeutic target in MM. Disclosures No relevant conflicts of interest to declare.

FOXM1, CDK6 and Rb Dependent Drug Resistance and Senescence in Myeloma

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4456-4456 ◽  
Author(s):  
Chunyan Gu ◽  
Ruini Chen ◽  
Xuefang Jing ◽  
Siegfried Janz ◽  
Ye Yang
Keyword(s):  
Drug Resistance ◽  
High Risk ◽  
Conflicts Of Interest ◽  
Expression Profiles ◽  
Physical Interaction ◽  
Mrna Levels ◽  
Agar Culture ◽  
Myeloma Cells

Abstract We recently reported that FOXM1 is a promising therapeutic target in multiple myeloma (MM), particularly for the subset of patients with high-risk disease.Because high-risk myeloma exhibits a strong predilection to early drug-resistant relapse following first-line therapy, we here decided to evaluate the role of FOXM1 in the acquisition of drug resistance by myeloma cells. We analyzed gene expression profiles of 88 paired myeloma samples at baseline and relapse from the UAMS Total Therapy 2 cohort and found that FOXM1 mRNA levels were significant upregulated in relapsed myeloma and that this was associated with poor event-free and overall survival. Laboratory studies showed that enforced expression of FOXM1 in human myeloma cell lines (HMCLs) results in decreased sensitivity of cells to widely used myeloma drugs, such as bortezomib and doxorubicin. This was observed in vitro, in both bulk cell and soft-agar culture, and in vivo using xenografting in mice. Biochemical analysis of HMCLs revealed physical interaction of FOXM1 with CDK6 and Rb, key regulators of cell cycle progression and cellular senescence, respectively.Treatment with small-compound CDK6 inhibitor, inhibited myeloma growth, decreased clonogenicity of myeloma, and ameliorated FOXM1-dependent senescence. Genetic and pharmacological targeting of FOXM1 in myeloma cells using shRNA and thiostreptone respectively, led to growth arrest and senescence, while elevated expression of FOXM1 reversed these phenotypes. In sum, our findings implicating the FOXM1-CDK6-Rb network in drug resistance and senescence of high-risk myeloma point to new treatment opportunities for this difficult-to-cure neoplasm. Disclosures No relevant conflicts of interest to declare.

scholarly journals Patient-derived organoids reflect the genetic profile of endometrial tumors and predict patient prognosis

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Hege F. Berg ◽  
Marta Espevold Hjelmeland ◽  
Hilde Lien ◽  
Heidi Espedal ◽  
Tina Fonnes ◽  
...  
Keyword(s):  
Endometrial Cancer ◽  
Tumor Heterogeneity ◽  
Treatment Strategies ◽  
Gene Signature ◽  
Model Systems ◽  
Rank Test ◽  
Genetic Profile ◽  
Resected Patient

Abstract Background A major hurdle in translational endometrial cancer (EC) research is the lack of robust preclinical models that capture both inter- and intra-tumor heterogeneity. This has hampered the development of new treatment strategies for people with EC. Methods EC organoids were derived from resected patient tumor tissue and expanded in a chemically defined medium. Established EC organoids were orthotopically implanted into female NSG mice. Patient tissue and corresponding models were characterized by morphological evaluation, biomarker and gene expression and by whole exome sequencing. A gene signature was defined and its prognostic value was assessed in multiple EC cohorts using Mantel-Cox (log-rank) test. Response to carboplatin and/or paclitaxel was measured in vitro and evaluated in vivo. Statistical difference between groups was calculated using paired t-test. Results We report EC organoids established from EC patient tissue, and orthotopic organoid-based patient-derived xenograft models (O-PDXs). The EC organoids and O-PDX models mimic the tissue architecture, protein biomarker expression and genetic profile of the original tissue. Organoids show heterogenous sensitivity to conventional chemotherapy, and drug response is reproduced in vivo. The relevance of these models is further supported by the identification of an organoid-derived prognostic gene signature. This signature is validated as prognostic both in our local patient cohorts and in the TCGA endometrial cancer cohort. Conclusions We establish robust model systems that capture both the diversity of endometrial tumors and intra-tumor heterogeneity. These models are highly relevant preclinical tools for the elucidation of the molecular pathogenesis of EC and identification of potential treatment strategies.

scholarly journals Inhibitory effect of naphthoquine phosphate against Babesia gibsoni in vitro and Babesia rodhaini in vivo

2021 ◽  
Author(s):  
Shengwei Ji ◽  
Mingming Liu ◽  
Eloiza May Galon ◽  
Mohamed Abdo Rizk ◽  
Bumduuren Tuvshintulga ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Treatment Strategies ◽  
Drug Repurposing ◽  
Significant Inhibition ◽  
Parasite Growth ◽  
New Drugs ◽  
Control Group ◽  
Babesia Gibsoni

Abstract Background: Drug resistance and severe side effects are major challenges in the treatment of babesiosis as they lead to less choices for treatment. Development of new drugs to enrich the treatment strategies and delay the emergence of drug resistance in parasites is still needed. Naphthoquine (NQ) combined with artemisinin treats Plasmodium infection by rapid parasite clearance. The current study repurposed NQ as a babesiosis drug treatment by evaluating the effects of naphthoquine phosphate (NQP) as a single dose treatment for babesiosis. Methods: In vitro anti-Babesia activity of NQP was tested on Babesia gibsoni cultures. The inhibition of parasite growth was verified using a SYBR green I-based fluorescence assay. In vivo efficacy of NQP was evaluated using BALB/c mice infected with Babesia rodhaini. The parasitemia level and hematocrit values were monitored. Results: The half maximal inhibitory concentration of NQP against B. gibsoni in vitro was 3.3 ± 0.5 μM. Oral administration of NQP for 5 successive days at a dose of 40 mg/kg of body weight resulted in significant inhibition on parasite growth compared with the control group. All mice in NQP-treated group survived, whereas the mice in control group died between days 6 and 9 post infection. Conclusion: This is the first study to evaluate the anti-Babesia activity of NQP in vitro and in vivo. The results showed that NQP is a promising drug for babesiosis treatment and drug repurposing may provide new treatment strategies for babesiosis.

scholarly journals Development of Targeted Therapies for Breast and Highly Aggressive Cancers

Proceedings ◽  
2020 ◽  
Vol 40 (1) ◽  
pp. 48
Author(s):  
Bulent Ozpolat
Keyword(s):  
Small Molecule ◽  
Targeted Therapies ◽  
Noncoding Rna ◽  
Small Molecule Inhibitors ◽  
Significant Heterogeneity ◽  
T Cell Therapy ◽  
Gene Therapies ◽  
Check Point Inhibitors

Cancer is one of the top two causes of deaths in the US and the world. Cancer therapy includes standard therapies such as surgery, chemotherapy and targeted therapies, by antibody and small molecule inhibitors, and immunotherapy (i.e., check point inhibitors, CAR-T cell therapy). More recently RNA-based targeted therapeutics were approved by FDA. Although there are about more than 100 targeted therapies, due to significant heterogeneity in patient tumors even in the same subtype of cancers, only faction of patient can benefit from targeted therapies due to lack of target expression in all patients. For some therapeutic targets, such as the most famous and one of the first identified oncogenes, KRAS, which is also considered as an “undrugabale” target expressed in cytoplasm and cannot be targeted by antibodies and small molecule inhibitors, currently there is no FDA approved inhibitors for patients. Therefore, gene targeted and RNA therapies overcome difficulties faced by the use of small molecule and antibodies provide promising new avenue for targeting these oncogenes. After several decades of research finally some of the gene targeted therapies emerged and are being tested in clinical trials. The talk will also give background in targeted therapies used in cancer patients and our novel targeted therapies. After overweening targeted therapies including gene therapies used in cancer with “pros of cons”, my talk will focus on development of RNA, noncoding RNA, small molecule and natural compound-based targeted therapies on the several highly aggressive cancers including triple negative breast cancer, pancreatic, and lung cancer. We discovered and validated EF2 Kinase as a novel molecular target and showed their clinical significance by demonstrating their association with significantly shorter patient survival in TNBC. Using in vitro and in vivo tumor models in mice, we demonstrated that EF2-Kinase regulates, cell proliferation, invasion, and tumorigenesis and nanotherapeutics approaches for targeting EF2-Kinase is highly effective for treatment of patients with highly aggressive cancers.

scholarly journals miR-5000-3p confers oxaliplatin resistance by targeting ubiquitin-specific peptidase 49 in colorectal cancer

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yan-yan Zhuang ◽  
Wa Zhong ◽  
Zhong-sheng Xia ◽  
Shu-zhen Lin ◽  
Man chung Chan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Colorectal Cancer ◽  
Drug Resistance ◽  
Critical Role ◽  
Treatment Strategies ◽  
Luciferase Reporter ◽  
Multi Drug Resistance ◽  
Gastrointestinal Malignancies

AbstractColorectal cancer (CRC) is the most common form of gastrointestinal malignancies. A growing number of reports focusing on oxaliplatin (OXA) resistance in CRC treatment have revealed that drug resistance is an urgent issue in clinical applications, especially for finding effective therapeutic targets. Recently, microRNAs (miRNAs) are reported to play a critical role in tumor progressions and multi-drug resistance. The main aim of this study is to establish whether miR-5000-3p is an oncogene that is resistant to OXA and further confirm its underlying regulatory role in CRC. The OXA-associated gene expression dataset in CRC cells was downloaded from Gene Expression Omnibus (GEO) database. Statistical software R was used for significance analysis of differentially expressed genes (DEGs) between OXA-resistant (OR)-CRC cells and CRC cells, and results indicated ubiquitin-specific peptidase 49 (USP49) was upregulated in OR-CRC cells. Luciferase reporter assay showed that USP49 was verified to act as a downstream target gene of miR-5000-3p. From the results of TCGA database, miR-5000-3p expression was upregulated and USP49 was downregulated in patients with CRC. The function of miR-5000-3p was detected using MTT assay, wound healing, Transwell, and flow cytometry assays. Moreover, through in vitro and in vivo experiments, miR-5000-3p expression was confirmed to be upregulated in CRC cells or OR-CRC cells comparing to normal cell lines. Molecular mechanism assays revealed that USP49 binds to the miR-5000-3p promoter to increase the expression of miR-5000-3p, resulting in cancer cells sensitized to OXA. To sum up, these results suggest that miR-5000-3p may be a novel biomarker involved in drug-resistance progression of CRC. Moreover, the drug-resistance mechanism of miR-5000-3p/USP49 axis provides new treatment strategies for CRC in clinical trials.

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