scholarly journals Efficacy of EGFR Inhibitors and NSAIDs Against Basal Bladder Cancers in a Rat Model: Daily vs. Weekly Dosing, Combining EGFR Inhibitors with Naproxen, and Effects on RNA Expression

2021 ◽  
pp. 1-11
Author(s):  
Ronald A. Lubet ◽  
Amit Kumar ◽  
Jennifer T. Fox ◽  
Ming You ◽  
Altaf Mohammed ◽  
...  

BACKGROUND: There are few effective treatments specifically aimed at basal bladder cancer. OBJECTIVE: Female F344 rats administered N-butyl-N-(4-hydroxybutyl)-nitrosamine (OH-BBN) develop large invasive bladder cancers. We determined the efficacy of daily vs weekly dosing of EGFR inhibitors, determined the efficacy of naproxen combined with an EGFR inhibitor, and performed RNA analysis of bladder tumors treated for 5 days with EGFR inhibitors or NO-naproxen to identify pharmacodynamic biomarkers. METHODS: Erlotinib (6 mg/Kg BW daily or 21 or 42 mg/Kg BW weekly), lapatinib (25 or 75 mg/Kg BW daily or 263 or 525 mg/Kg BW weekly) and/or naproxen (30 mg/Kg BW daily) were administered to OH-BBN-treated rats beginning 2–12 weeks post OH-BBN. Rats were sacrificed 28 weeks after the final OH-BBN treatment to determine the effects of the EGFR inhibitors + naproxen on bladder weights and tumor development. In a separate study, rats were treated with OH-BBN. When palpable tumors developed, rats were treated with erlotinib, lapatinib, gefitinib, or the NSAID NO-naproxen for 5 days. RNA analysis was performed on the tumors. RESULTS: Daily or weekly dosing of erlotinib or lapatinib and daily dosing of naproxen reduced large tumor formation up to 70%, while combining daily lapatinib and naproxen reduced tumors 100%. RNA Analysis: All EGFR inhibitors strongly reduced cell proliferation and chromosome replication pathways, while NO-naproxen altered the G protein receptor, oxygen homeostasis and immune function pathways. CONCLUSIONS: While daily and weekly dosing with EGFR inhibitors and naproxen were effective, combining lapatinib and naproxen yielded no tumors. This might encourage its clinical use in an adjuvant setting with superficial basal tumors, and perhaps even in a more advanced setting. Furthermore, RNA analysis identified specific pathways that might be potential pharmacodynamic biomarkers in clinical trials.

2017 ◽  
Vol 18 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Andres Morales La Madrid ◽  
Mark W. Kieran

Central nervous system (CNS) tumors represent the second most prevalent group of cancers in children and adolescents, yet account for the majority of childhood cancer-related deaths and considerable morbidity among survivors, due to high-intensity non-selective standard therapies delivered to immature nervous system structures undergoing development. These tumors arise at different ages –not infrequently very early in life-, in different locations and cellular contexts, have varied cell types of origin, and have heterogeneous responses to the “classic” current therapeutic approaches. Demographic, radiologic and morphological characterization have several limitations, putting into the “classic boxes” heterogeneous tumors that are diverse in their genetic and epigenetic background and that will likely behave biologically different. Given that, epigenetic disruption (i.e. DNA methylation, histone modification and chromatin remodeling) is a common feature identified more and more frequently in pediatric cancer, it is logical to speculate that interrogating epigenetic marks may help to further define the molecular profile, and therefore tumor biology, evolution and treatment of these tumors. An integrated approach that incorporates traditional features complemented with genetic and epigenenetic specific markers offers tremendous promise to “risk-group” stratification and better prognostication. Also, it will help unveil the key driver pathways for tumor formation and for the discovery of targeted therapy for neoplasms that appear in the developing brain, facilitating early identification of therapy responders and track accurately disease progression. In this paper, we reviewed the most representative pediatric brain tumors where epigenetic alterations have been identified as initiating or driving events in tumor development, maintenance or progression.


2002 ◽  
Vol 283 (2) ◽  
pp. F262-F270 ◽  
Author(s):  
Hae-Seong Yoon ◽  
Terrence J. Monks ◽  
Jeffrey I. Everitt ◽  
Cheryl L. Walker ◽  
Serrine S. Lau

Although 2,3,5-tris-(glutathion- S-yl)hydroquinone (TGHQ; 2.5 μmol/kg ip) markedly increased cell proliferation within the outer stripe of the outer medulla (OSOM) of the kidney in both wild-type ( Tsc2+/+ ) and mutant Eker rats ( Tsc2 EK/+), only TGHQ-treated Tsc2 EK/+ rats developed renal tumors, indicating that cell proliferation per se was not sufficient for tumor development. Tuberin expression was initially induced within the OSOM after TGHQ treatment but was lost within TGHQ-induced renal tumors. High extracellular signal-regulated kinase (ERK) activity occurred in the OSOM of Tsc2 EK/+ rats at 4 mo and in TGHQ-induced renal tumors. Cyclin D1 was also highly expressed in TGHQ-induced renal tumors. Reexpression of Tsc2 in tuberin-negative cells decreased ERK activity, consistent with the growth-suppressive effects of this tumor suppressor gene. Thus 1) stimulation of cell proliferation after toxicant insult is insufficient for tumor formation; 2) tuberin induction after acute tissue injury suggests that Tsc2 is an acute-phase response gene, limiting the proliferative response after injury; and 3) loss of Tsc2 gene function is associated with cell cycle deregulation.


2018 ◽  
Author(s):  
Hui San Chin ◽  
Mark F. van Delft ◽  
Robert L. Ninnis ◽  
Mark X. Li ◽  
Iris K. L. Tan ◽  
...  

AbstractIntrinsic apoptosis is critical for normal physiology including the prevention of tumor formation. BAX and BAK are essential for mediating this process and for the cytotoxic action of many anticancer drugs. BAX and BAK are thought to act in a functionally redundant manner and are considered to be regulated similarly. From an unbiased genome-wide CRISPR/Cas9 screen, we identified VDAC2 (voltage-dependent anion channel 2) as essential for BAX, but not BAK, to function. The genetic deletion of VDAC2 abrogated the association of BAX and BAK with mitochondrial complexes that contain VDAC1, VDAC2 and VDAC3. By disrupting its localization to mitochondria, BAX is rendered completely ineffective. Moreover, we defined an interface unique to VDAC2 that is required to drive BAX activity. Consequently, interfering with this interaction or deleting VDAC2 phenocopied the loss of BAX, including impairing the killing of tumor cells by anti-cancer agents such as the BCL-2 inhibitor venetoclax. Furthermore, the ability of BAX to prevent tumor formation was attenuated in the absence of VDAC2. Taken together, our studies show for the first time that BAX-mediated apoptosis, but not BAK-mediated apoptosis, is critically dependent on VDAC2, hence revealing the differential regulation of BAX and BAK.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi221-vi221
Author(s):  
Carolin Göbel ◽  
Dörthe Holdhof ◽  
Melanie Schoof ◽  
Catena Kresbach ◽  
Ulrich Schüller

Abstract Mutations in SMARCA4 are frequently identified in medulloblastoma, the most common pediatric malignant brain tumor. However, the functional significance of these mutations and their suitability as a therapeutic target remain largely unclear. Medulloblastomas are divided into 4 subgroups according to their localization, molecular biology, and clinical course: WNT, SHH, Group 3, and Group 4. Group 3 medulloblastomas are associated with the poorest outcome and frequently show amplifications of the oncogene MYC. Additionally, SMARCA4 is mutated in around 15 % of cases. The few mouse models developed for this entity so far all involve the overexpression of MYC, mostly in combination with other drivers. However, none of these models include alterations in Smarca4. In our approach, we combined an overexpression of MYC with a loss of SMARCA4 in granule cell precursors, which successfully induced tumor formation in mice. For this purpose, granule cell precursors were isolated from 7-day-old Math1-creER T2 ::Smarca4 fl/fl pups after tamoxifen induced loss of SMARCA4. MYC overexpression was achieved by lentiviral transduction and transduced cells were transplanted into immunodeficient CD1 nu/nu mice. Preliminary results within a small cohort showed tumor formation in 5/19 transplanted mice (26 %) after 6 months. Immunohistochemically, tumors all stained negative for SMARCA4. In a next step, additional cohorts will elucidate if tumor development is indeed accelerated by or even dependent on the loss of SMARCA4. Additionally, the neoplastic potential of tumor cells will be verified with the aid of secondary recipient mice. To evaluate to what extent the generated tumors are comparable to human Group 3 medulloblastomas, tumors will be extensively analyzed on a morphological, transcriptional, and epigenetic level. Altogether, we hope to establish a suitable mouse model for SMARCA4 mutated Group 3 medulloblastoma that will help to elucidate the role of SMARCA4 in tumor development and to identify new therapeutic targets.


2009 ◽  
Vol 2 ◽  
pp. CCRep.S3126 ◽  
Author(s):  
Cem Onal ◽  
Berrin Pehlivan ◽  
Nebil Bal ◽  
Erkan Topkan ◽  
Ferhat Kilinc ◽  
...  

Sarcomatoid carcinoma is a rare tumor of the urinary bladder accounting for less than 0.5% of all primary urinary bladder tumors. Since the patients were presented with large tumor with extended stages, outcome was found to be poor. In order to improve local control, adjuvant local treatment may be practical. We report a rare case with sarcomatoid carcinoma of the urinary bladder diagnosed with immunuhistochemical (IHC) study and treated with 3D-conformal radiotherapy (3DCRT) post-operatively. A 55-year old female patient complained about painless hematuria for 2 months. Computed tomography of the pelvic region revealed tumor and wall thickening at the left posterolateral side of the bladder. Total cystectomy with lymph node dissection and total abdominal hysterectomy and bilateral salphingo-oopherectomy was performed and histopathological and immunohistochemical findings strongly correlate with sarcomatoid carcinoma. The patient was treated with 3D conformal radiotherapy (3DCRT) with a total dose of 59.4 Gy with 1.8 Gy fractional daily doses. Patient was alive without any local recurrence and distant metastasis 10 months after surgery.


2015 ◽  
Vol 36 (1) ◽  
pp. 221-232 ◽  
Author(s):  
Mercedes Nadal-Serrano ◽  
Jorge Sastre-Serra ◽  
Adamo Valle ◽  
Pilar Roca ◽  
Jordi Oliver

Background/Aims: Large-scale epidemiological studies support a correlation between obesity and breast cancer in postmenopausal women. Circulating leptin levels are increased in obese and it has been suggested to play a significant role in mammary tumor formation and progression. Moreover, regulation of oxidative stress is another important factor in both tumor development and responses to anticancer therapies. The aim of this study was to examine the relationship between oxidative stress and chronic leptin exposure. Methods: We treated MCF-7 breast cancer cells with 100 ng/mL leptin for 10 days and analyzed cell growth, ROS production and oxidative damage, as well as, some of the main antioxidant systems. Furthermore, since the hyperleptinemia has been associated with a worse pathology prognosis, we decided to test the influence of leptin in response to cisplatin anticancer treatment. Results: Leptin signalling increased cell proliferation but reduced ROS production, as well as, oxidative damage. We observed an upregulation of SIRT1 after leptin exposure, a key regulator of stress response and metabolism. Additionally, leptin counteracted cisplatin-induced cytotoxicity in tumor cells, showing a decrease in cell death. Conclusion: Chronic leptin could contribute to the effective regulation of endogenous and treatment-induced oxidative stress, and it contributes to explain in part its proliferative effects.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Yehuda Schlesinger ◽  
Oshri Yosefov-Levi ◽  
Dror Kolodkin-Gal ◽  
Roy Zvi Granit ◽  
Luriano Peters ◽  
...  

Abstract Acinar metaplasia is an initial step in a series of events that can lead to pancreatic cancer. Here we perform single-cell RNA-sequencing of mouse pancreas during the progression from preinvasive stages to tumor formation. Using a reporter gene, we identify metaplastic cells that originated from acinar cells and express two transcription factors, Onecut2 and Foxq1. Further analyses of metaplastic acinar cell heterogeneity define six acinar metaplastic cell types and states, including stomach-specific cell types. Localization of metaplastic cell types and mixture of different metaplastic cell types in the same pre-malignant lesion is shown. Finally, single-cell transcriptome analyses of tumor-associated stromal, immune, endothelial and fibroblast cells identify signals that may support tumor development, as well as the recruitment and education of immune cells. Our findings are consistent with the early, premalignant formation of an immunosuppressive environment mediated by interactions between acinar metaplastic cells and other cells in the microenvironment.


2020 ◽  
Vol 21 (23) ◽  
pp. 9295
Author(s):  
Nadine Brandes ◽  
Slavica Hristomanova Mitkovska ◽  
Dominik Simon Botermann ◽  
Wiebke Maurer ◽  
Anna Müllen ◽  
...  

Basal cell carcinoma (BCC) originate from Hedgehog/Patched signaling-activated epidermal stem cells. However, the chemically induced tumorigenesis of mice with a CD4Cre-mediated biallelic loss of the Hedgehog signaling repressor Patched also induces BCC formation. Here, we identified the cellular origin of CD4Cre-targeted BCC progenitors as rare Keratin 5+ epidermal cells and show that wildtype Patched offspring of these cells spread over the hair follicle/skin complex with increasing mouse age. Intriguingly, Patched mutant counterparts are undetectable in age-matched untreated skin but are getting traceable upon applying the chemical tumorigenesis protocol. Together, our data show that biallelic Patched depletion in rare Keratin 5+ epidermal cells is not sufficient to drive BCC development, because the spread of these cells is physiologically suppressed. However, bypassing the repression of Patched mutant cells, e.g., by exogenous stimuli, leads to an accumulation of BCC precursor cells and, finally, to tumor development.


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