Acquired temozolomide resistance in MGMT-deficient glioblastoma cells is associated with regulation of DNA repair by DHC2

Abstract The acquisition of temozolomide resistance is a major clinical challenge for glioblastoma treatment. Chemoresistance in glioblastoma is largely attributed to repair of temozolomide-induced DNA lesions by O6-methylguanine-DNA methyltransferase (MGMT). However, some MGMT-deficient glioblastomas are still resistant to temozolomide, and the underlying molecular mechanisms remain unclear. We found that DYNC2H1 (DHC2) was expressed more in MGMT-deficient recurrent glioblastoma specimens and its expression strongly correlated to poor progression-free survival in MGMT promotor methylated glioblastoma patients. Furthermore, silencing DHC2, both in vitro and in vivo, enhanced temozolomide-induced DNA damage and significantly improved the efficiency of temozolomide treatment in MGMT-deficient glioblastoma. Using a combination of subcellular proteomics and in vitro analyses, we showed that DHC2 was involved in nuclear localization of the DNA repair proteins, namely XPC and CBX5, and knockdown of either XPC or CBX5 resulted in increased temozolomide-induced DNA damage. In summary, we identified the nuclear transportation of DNA repair proteins by DHC2 as a critical regulator of acquired temozolomide resistance in MGMT-deficient glioblastoma. Our study offers novel insights for improving therapeutic management of MGMT-deficient glioblastoma.

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Drug-induced DNA damage and tumor chemosensitivity.

Journal of Clinical Oncology ◽

10.1200/jco.1990.8.12.2062 ◽

1990 ◽

Vol 8 (12) ◽

pp. 2062-2084 ◽

Cited By ~ 65

Author(s):

R J Epstein

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Tumor Cell ◽

Malignant Disease ◽

Dna Lesions ◽

Drug Induced ◽

Cell Subpopulations ◽

Therapeutic Cell

Cytotoxic drugs act principally by damaging tumor-cell DNA. Quantitative analysis of this interaction provides a basis for understanding the biology of therapeutic cell kill as well as a rational strategy for optimizing and predicting tumor response. Recent advances have made it possible to correlate assayed DNA lesions with cytotoxicity in tumor cell lines, in animal models, and in patients with malignant disease. In addition, many of the complex interrelationships between DNA damage, DNA repair, and alterations of gene expression in response to DNA damage have been defined. Techniques for modulating DNA damage and cytotoxicity using schedule-specific cytotoxic combinations, DNA repair inhibitors, cell-cycle manipulations, and adjunctive noncytotoxic drug therapy are being developed, and critical therapeutic targets have been identified within tumor-cell subpopulations and genomic DNA alike. Most importantly, methods for predicting clinical response to cytotoxic therapy using both in vitro markers of tumor-cell sensitivity and in vivo measurements of drug-induced DNA damage are now becoming a reality. These advances can be expected to provide a strong foundation for the development of innovative cytotoxic drug strategies over the next decade.

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The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-021-84117-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hiroaki Kanzaki ◽

Tetsuhiro Chiba ◽

Junjie Ao ◽

Keisuke Koroki ◽

Kengo Kanayama ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Molecular Mechanisms ◽

Kinase Inhibitors ◽

Progression Free Survival ◽

Erk Signaling ◽

Enzyme Linked Immunosorbent Assay ◽

Antitumor Effects ◽

The Impact

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.

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RuvAB and RecG Are Not Essential for the Recovery of DNA Synthesis Following UV-Induced DNA Damage in Escherichia coli

Genetics ◽

10.1093/genetics/166.4.1631 ◽

2004 ◽

Vol 166 (4) ◽

pp. 1631-1640 ◽

Cited By ~ 4

Author(s):

Janet R Donaldson ◽

Charmain T Courcelle ◽

Justin Courcelle

Keyword(s):

Dna Damage ◽

Dna Synthesis ◽

Dna Lesions ◽

Replication Forks ◽

Wild Type ◽

Replication Machinery ◽

Dna Junctions ◽

Fork Regression

Abstract Ultraviolet light induces DNA lesions that block the progression of the replication machinery. Several models speculate that the resumption of replication following disruption by UV-induced DNA damage requires regression of the nascent DNA or migration of the replication machinery away from the blocking lesion to allow repair or bypass of the lesion to occur. Both RuvAB and RecG catalyze branch migration of three- and four-stranded DNA junctions in vitro and are proposed to catalyze fork regression in vivo. To examine this possibility, we characterized the recovery of DNA synthesis in ruvAB and recG mutants. We found that in the absence of either RecG or RuvAB, arrested replication forks are maintained and DNA synthesis is resumed with kinetics that are similar to those in wild-type cells. The data presented here indicate that RecG- or RuvAB-catalyzed fork regression is not essential for DNA synthesis to resume following arrest by UV-induced DNA damage in vivo.

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4-Acetylantrocamol LT3 Inhibits Glioblastoma Cell Growth and Downregulates DNA Repair Enzyme O6-Methylguanine-DNA Methyltransferase

The American Journal of Chinese Medicine ◽

10.1142/s0192415x21500476 ◽

2021 ◽

pp. 1-17

Author(s):

Shih-Yu Lee ◽

I-Chuan Yen ◽

Jang-Chun Lin ◽

Min-Chieh Chung ◽

Wei-Hsiu Liu

Keyword(s):

Dna Repair ◽

Cell Viability ◽

Colony Formation ◽

Dna Methyltransferase ◽

Growth Factor Receptor ◽

Repair Enzyme ◽

U251 Cell ◽

Methylguanine Dna Methyltransferase

Glioblastoma multiforme (GBM) is a deadly malignant brain tumor that is resistant to most clinical treatments. Novel therapeutic agents that are effective against GBM are required. Antrodia cinnamomea has shown antiproliferative effects in GBM cells. However, the exact mechanisms and bioactive components remain unclear. Thus, the present study aimed to investigate the effect and mechanism of 4-acetylantrocamol LT3 (4AALT3), a new ubiquinone from Antrodia cinnamomeamycelium, in vitro. U87 and U251 cell lines were treated with the indicated concentration of 4AALT3. Cell viability, cell colony-forming ability, migration, and the expression of proteins in well-known signaling pathways involved in the malignant properties of glioblastoma were then analyzed by CCK-8, colony formation, wound healing, and western blotting assays, respectively. We found that 4AALT3 significantly decreased cell viability, colony formation, and cell migration in both in vitro models. The epidermal growth factor receptor (EGFR), phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR), Hippo/yes-associated protein (YAP), and cAMP-response element binding protein (CREB) pathways were suppressed by 4AALT3. Moreover, 4AALT3 decreased the level of DNA repair enzyme O6-methylguanine-DNA methyltransferase and showed a synergistic effect with temozolomide. Our findings provide the basis for exploring the beneficial effect of 4AALT3 on GBM in vivo.

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Vimentin provides the mechanical resilience required for amoeboid migration and protection of the nucleus

10.1101/720946 ◽

2019 ◽

Cited By ~ 4

Author(s):

Luiza Da Cunha Stankevicins ◽

Marta Urbanska ◽

Daniel AD. Flormann ◽

Emmanuel Terriac ◽

Zahra Mostajeran ◽

...

Keyword(s):

Dna Damage ◽

Dendritic Cells ◽

Cell Migration ◽

Molecular Mechanisms ◽

Cell Cortex ◽

Dna Double Strand Breaks ◽

Nuclear Positioning ◽

Mechanical Stiffness

AbstractDendritic cells use amoeboid migration through constricted passages to reach the lymph nodes, and this homing function is crucial for immune responses. Amoeboid migration requires mechanical resilience, however, the underlying molecular mechanisms for this type of migration remain unknown. Because vimentin intermediate filaments (IFs) and microfilaments regulate adhesion-dependent migration in a bidirectional manner, we analyzed if they exert a similar control on amoeboid migration. Vimentin was required for cellular resilience, via a joint interaction between vimentin IFs and F-actin. Reduced actin mobility in the cell cortex of vimentin-reduced cells indicated that vimentin promotes Factin subunit exchange and dynamics. These mechano-dynamic alterations in vimentin-deficient dendritic cells impaired amoeboid migration in confined environments in vitro and blocked lymph node homing in mouse experiments in vivo. Correct nuclear positioning is important in confined amoeboid migration both to minimize resistance and to avoid DNA damage. Vimentin-deficiency also led to DNA double strand breaks in the compressed dendritic cells, pointing to a role of vimentin in nuclear positioning. Together, these observations show that vimentin IF-microfilament interactions provide both the specific mechano-dynamics required for dendritic cell migration and the protection the genome needs in compressed spaces.Summary statementVimentin — in joint action with actin — mediates the mechanical stiffness of cells required for amoeboid cell migration through confined spaces and protects the nucleus from DNA damage.

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CTNI-21. PHASE 2 STUDY OF VAL-083 AND RADIOTHERAPY IN NEWLY DIAGNOSED MGMT-UNMETHYLATED GBM

Neuro-Oncology ◽

10.1093/neuonc/noab196.246 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi63-vi64

Author(s):

Zhong-ping Chen ◽

Cheng-Cheng Guo ◽

Yang Qun-ying ◽

Jia-Wei Li ◽

Shao-xiong Wu ◽

...

Keyword(s):

Dna Methyltransferase ◽

Radiation Treatment ◽

Gene Promoter ◽

Progression Free Survival ◽

Common Adverse Event ◽

Phase 2 ◽

Newly Diagnosed ◽

Phase 2 Study

Abstract Approximately 60% of glioblastoma multiforme (GBM) patients possess an unmethylated methylguanine DNA-methyltransferase (MGMT) gene promoter, which confers a limited clinical response to standard-of-care treatment with temozolomide (TMZ), resulting in shorter median survival when compared to patients with a methylated MGMT promoter. VAL-083 is a novel bi-functional DNA targeting agent that induces interstrand DNA cross-links at N7-guanine, leading to DNA double-strand breaks and ultimately cell death. VAL-083 circumvents MGMT-mediated TMZ resistance in vitro and in vivo. A Phase 2 study has been conducted to evaluate efficacy and safety of VAL-083 when administered concurrently with radiation therapy (RT) in newly diagnosed MGMT unmethylated GBM. The study was conducted in 2 stages: Stage 1 was a dose-escalation phase to confirm the dose of VAL-083 in this setting. Patients received VAL-083 at 20, 30, or 40 mg/m2/day x 3 days every 21 days along with standard radiation treatment (RT) (2 Gy/day, 5 days/week for 6 weeks). At the end of this stage, 30 mg/m2/day of VAL-083 in combination with RT was generally safe and well-tolerated. Stage 2 was an expansion phase to enroll up to 20 additional patients at the 30 mg/m2/day of VAL-083 in combination with RT. All patients have been enrolled, with a total of 29 patients in the study, and 25 patients receiving 30 mg/m2/day VAL-083. All 29 patients have completed treatment and patients are in the follow-up phase of the study. Consistent with our prior experience, myelosuppression was the most common adverse event. As of March 2021, 22/29 (75.9%) subjects had disease progression. The median progression free survival for all patients enrolled was 9.3 (95%CI: 6.4-12.0) months. Sixteen (16/29; 55.2%) patients had died, and median overall survival for all patients enrolled was 19.6 (95%CI: 14.0-22.4) months. Further safety and efficacy updates will be presented at the meeting. Clinicaltrials.gov identifier: NCT03050736.

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Simultaneous targeting of DNA replication and homologous recombination in glioblastoma with a polyether ionophore

Neuro-Oncology ◽

10.1093/neuonc/noz159 ◽

2019 ◽

Cited By ~ 1

Author(s):

Yi Chieh Lim ◽

Kathleen S Ensbey ◽

Carolin Offenhäuser ◽

Rochelle C J D’souza ◽

Jason K Cullen ◽

...

Keyword(s):

Dna Repair ◽

Homologous Recombination ◽

First Generation ◽

Ex Vivo ◽

Drug Efficacy ◽

Tumor Formation ◽

Dna Lesions ◽

Dual Functions

Abstract Background Despite significant endeavor having been applied to identify effective therapies to treat glioblastoma (GBM), survival outcomes remain intractable. The greatest nonsurgical benefit arises from radiotherapy, though tumors typically recur due to robust DNA repair. Patients could therefore benefit from therapies with the potential to prevent DNA repair and synergize with radiotherapy. In this work, we investigated the potential of salinomycin to enhance radiotherapy and further uncover novel dual functions of this ionophore to induce DNA damage and prevent repair. Methods In vitro primary GBM models and ex vivo GBM patient explants were used to determine the mechanism of action of salinomycin by immunoblot, flow cytometry, immunofluorescence, immunohistochemistry, and mass spectrometry. In vivo efficacy studies were performed using orthotopic GBM animal xenograft models. Salinomycin derivatives were synthesized to increase drug efficacy and explore structure-activity relationships. Results Here we report novel dual functions of salinomycin. Salinomycin induces toxic DNA lesions and prevents subsequent recovery by targeting homologous recombination (HR) repair. Salinomycin appears to target the more radioresistant GBM stem cell–like population and synergizes with radiotherapy to significantly delay tumor formation in vivo. We further developed salinomycin derivatives which display greater efficacy in vivo while retaining the same beneficial mechanisms of action. Conclusion Our findings highlight the potential of salinomycin to induce DNA lesions and inhibit HR to greatly enhance the effect of radiotherapy. Importantly, first-generation salinomycin derivatives display greater efficacy and may pave the way for clinical testing of these agents.

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TIE2 Associates with Caveolae and Regulates Caveolin-1 To Promote Their Nuclear Translocation

Molecular and Cellular Biology ◽

10.1128/mcb.00142-17 ◽

2017 ◽

Vol 37 (21) ◽

Cited By ~ 8

Author(s):

Mohammad B. Hossain ◽

Rehnuma Shifat ◽

Jingyi Li ◽

Xuemei Luo ◽

Kenneth R. Hess ◽

...

Keyword(s):

Dna Repair ◽

Molecular Mechanisms ◽

Nuclear Translocation ◽

Subcellular Fractionation ◽

Tyrosine Kinase Receptor ◽

Histone H4 ◽

Small Interfering Rnas ◽

Caveolin 1

ABSTRACT DNA repair pathways are aberrant in cancer, enabling tumor cells to survive standard therapies—chemotherapy and radiotherapy. Our group previously reported that, upon irradiation, the membrane-bound tyrosine kinase receptor TIE2 translocates into the nucleus and phosphorylates histone H4 at Tyr51, recruiting ABL1 to the DNA repair complexes that participate in the nonhomologous end-joining pathway. However, no specific molecular mechanisms of TIE2 endocytosis have been reported. Here, we show that irradiation or ligand-induced TIE2 trafficking is dependent on caveolin-1, the main component of caveolae. Subcellular fractionation and confocal microscopy demonstrated TIE2/caveolin-1 complexes in the nucleus, and using inhibitor or small interfering RNAs (siRNAs) against caveolin-1 or Tie2 inhibited their trafficking. TIE2 was found in caveolae and directly phosphorylated caveolin-1 at Tyr14 in vitro and in vivo. This modification regulated the generation of TIE2/caveolin-1 complexes and was essential for TIE2/caveolin-1 nuclear translocation. Our data further demonstrate that the combination of TIE2 and caveolin-1 inhibitors resulted in significant radiosensitization of malignant glioma cells, which will guide the development of combinatorial treatment with radiotherapy for patients with glioblastoma.

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Phase I/IIa Study of Cilengitide and Temozolomide With Concomitant Radiotherapy Followed by Cilengitide and Temozolomide Maintenance Therapy in Patients With Newly Diagnosed Glioblastoma

Journal of Clinical Oncology ◽

10.1200/jco.2009.26.6650 ◽

2010 ◽

Vol 28 (16) ◽

pp. 2712-2718 ◽

Cited By ~ 286

Author(s):

Roger Stupp ◽

Monika E. Hegi ◽

Bart Neyns ◽

Roland Goldbrunner ◽

Uwe Schlegel ◽

...

Keyword(s):

Phase I ◽

Promoter Methylation ◽

Dna Methyltransferase ◽

Progression Free Survival ◽

Recurrent Glioblastoma ◽

Mgmt Promoter Methylation ◽

Newly Diagnosed ◽

Mgmt Promoter ◽

Newly Diagnosed Glioblastoma

Purpose Invasion and migration are key processes of glioblastoma and are tightly linked to tumor recurrence. Integrin inhibition using cilengitide has shown synergy with chemotherapy and radiotherapy in vitro and promising activity in recurrent glioblastoma. This multicenter, phase I/IIa study investigated the efficacy and safety of cilengitide in combination with standard chemoradiotherapy in newly diagnosed glioblastoma. Patients and Methods Patients (age ≥ 18 to ≤ 70 years) were treated with cilengitide (500 mg) administered twice weekly intravenously in addition to standard radiotherapy with concomitant and adjuvant temozolomide. Treatment was continued until disease progression or for up to 35 weeks. The primary end point was progression-free survival (PFS) at 6 months. Results Fifty-two patients (median age, 57 years; 62% male) were included. Six- and 12-month PFS rates were 69% (95% CI, 54% to 80%) and 33% (95% CI, 21% to 46%). Median PFS was 8 months (95% CI, 6.0 to 10.7 months). Twelve- and 24-month overall survival (OS) rates were 68% (95% CI, 53% to 79%) and 35% (95% CI, 22% to 48%). Median OS was 16.1 months (95% CI, 13.1 to 23.2 months). PFS and OS were longer in patients with tumors with O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation (13.4 and 23.2 months) versus those without MGMT promoter methylation (3.4 and 13.1 months). The combination of cilengitide with temozolomide and radiotherapy was well tolerated, with no additional toxicity. No pharmacokinetic interactions between temozolomide and cilengitide were identified. Conclusion Compared with historical controls, the addition of concomitant and adjuvant cilengitide to standard chemoradiotherapy demonstrated promising activity in patients with glioblastoma with MGMT promoter methylation.

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Role of GADD153 (growth arrest- and DNA damage-inducible gene 153) in vascular smooth muscle cell apoptosis

Clinical Science ◽

10.1042/cs1000275 ◽

2001 ◽

Vol 100 (3) ◽

pp. 275-281 ◽

Cited By ~ 11

Author(s):

Michiya IGASE ◽

Takafumi OKURA ◽

Michitsugu NAKAMURA ◽

Yasunori TAKATA ◽

Yutaka KITAMI ◽

...

Keyword(s):

Dna Damage ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Molecular Mechanisms ◽

Growth Arrest ◽

Cell Contact ◽

Inducible Gene

GADD153 (growth arrest- and DNA damage-inducible gene 153) is expressed at very low levels in growing cells, but is markedly induced in response to a variety of cellular stresses, including glucose deprivation, exposure to genotoxic agents and other growth-arresting situations. Forced expression of GADD153 induces cell cycle arrest in many types of cells. It is also reported that GADD153 is directly associated with apoptosis. Recently we have reported that platelet-derived growth factor (PDGF)-BB induces apoptosis in cultured vascular smooth muscle cells (VSMC), but only when 100% confluency is reached. These results suggested that cell–cell contact inhibition (cell growth arrest) may be a critical factor for induction of VSMC apoptosis by PDGF-BB. In the present study, we explored the role of GADD153, one of a number of growth-arrest-related gene products, in the molecular mechanisms of VSMC apoptosis in vitro and in vivo. GADD153 was markedly induced at both the mRNA and protein levels, in parallel with the induction of VSMC apoptosis, after treatment with PDGF-BB. Moreover, overexpression of GADD153 in VSMC significantly reduced cell viability and induced apoptosis. In the carotid artery balloon injury model in rats, GADD153 protein was expressed in apoptotic VSMC which were positively stained by in situ DNA labelling. These results demonstrate an important role for GADD153 in the molecular mechanisms of VSMC apoptosis.

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