[18F]FLT Is Superior to [18F]FDG to Early Predict Response to Specific Inhibitors of NPM-ALK-Dependent Pathways In a Human ALCL Xenograft Model

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2849-2849
Author(s):  
Nicolas Graf ◽  
Zhoulei Li ◽  
Ken Herrmann ◽  
Alexandra Junger ◽  
Daniel Weh ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Tumor Growth ◽  
Fdg Pet ◽  
Xenograft Model ◽  
Large Cell ◽  
Histopathological Analysis ◽  
Lymphoma Cells ◽  
Flt Pet

Abstract Abstract 2849 Purpose: The thymidine analogue [18F]fluorothymidine (FLT) has been shown to reflect proliferation of high-grade lymphoma cells both in preclinical and clinical studies. In this preclinical in vitro and in vivo study we assessed early FLT-uptake as an adequate and robust surrogate marker for response to inhibitors of Nucleophosmin-anaplastic lymphoma kinase (NPM-ALK)-dependent pathways in an anaplastic large cell lymphoma (ALCL) xenotransplant model. Methods: In vitro investigations included viability assessment (MTT assay), cell cycle analysis using propidium iodide staining and western blotting to characterize response of the ALCL cell lines SUDHL-1 and Karpas299 to treatment with heat shock protein 90 (Hsp90) inhibitor NVP-AUY922, the Phosphoinositide 3-kinase (PI3K) inhibitor BGT226 or the mammalian target of rapamycin (mTOR) inhibitor RAD001. Thymidine metabolism in severe combined immunodeficient (SCID) mice bearing SUDHL-1 or Karpas 299 lymphoma xenotransplants was assessed non-invasively prior to and early in the course of therapy (48h to 7 days) by FLT and FDG positron emission tomography (FLT-PET and FDG-PET) using a dedicated small animal PET system. Tumor-to-background ratios (TBR) of FLT-PET were compared to that of PET using the standard radiotracer [18F]fluorodeoxyglucose (FDG). Reference for tumor response was local control of the tumor measured by shifting calliper and histopathological analysis of explanted lymphomas. Results: In vitro, SUDHL-1 cells were sensitive to all three inhibitors (IC50 AUY922= 50 nM; IC50 BGT266= 10 nM; IC50 RAD001= 1 nM). These cells showed a dose-dependent induction of cell-cycle arrest in G1-phase and reduction of S-Phase after 24 to 48 hours and - to a lesser extent - increase of apoptosis. Incubation of SUDHL-1 cells with NVP-AUY922 (50 nM) for 24 hours led to a 70% reduction of ALK level and a abrogation of Akt phosphorylation as determined by western blot analysis. Likewise, no phosphorylation of Akt was detectable after incubation with BGT266 (10 nM) already after 4 hours. RAD001 (0.1-1nM, 24h) completely inhibited phosphorylation of p70 S6K. In contrast, Karpas299 cells were only sensitive to RAD001-induced cell cycle arrest, but insensitive to NVP-AUY922 and BGT266. In vivo, we performed FLT- and FDG-PET scans to monitor inhibition of tumor growth in the course of therapy with NVP-AUY922. Tumor volume in treated animals bearing SUDHL-1 lymphomas showed modest increase within the first week (median increase= + 25%, range -30% to + 80%, n=8) as opposed to a 3.8-fold increase in untreated control animals. After 14 days a clear reduction of tumor mass could be observed (median= - 25%, range -40% to + 30%, n=4). Median TBR of FLT-PET decreased significantly to 40% compared to baseline as earlier as 5 days after initiation of therapy (range 32–67%, n=8, p=0,008). In contrast, the pattern of TBR in FDG-PET did not show any clear tendency (median TBR 79%, range 36%-161%, n=8, p=0,73). We then investigated the ability of FLT-PET to differentiate between sensitive and resistant lymphoma cells. Therefore, mice bearing Karpas299 lymphomas were treated with NVP-AUY922 (resistant in vitro) or RAD001 (sensitive in vitro). According to our in vitro results, no effect was seen during treatment with NVP-AUY299 as indicated by about 3-fold tumor growth on day 7 and increase of median TBR in FLT-PET to 162% (range 106–177%, p=0,008, n=8) on day 2. In contrast, mice receiving RAD001 showed a deceleration of tumor development with doubling of tumor volume within the first week (range -20% to + 320%, n=10) that remained fairly constant over the following weeks. FLT-PET imaging indicated a slight increase of TBR correctly reflecting tumor growth kinetics (median=126%, range 60–129%, no p-value). A larger cohort is currently investigated as well as histopathological analysis of explanted lymphomas. The updated data will be presented at the meeting. Conclusion: In contrast to FDG-PET, FLT-PET is able to predict response to specific inhibitors early in the course of the therapy using a anaplastic large cell lymphoma xenograft model and is able to distinguish between sensitive and resistant lymphoma cells. Disclosures: No relevant conflicts of interest to declare.

CRM1 As a New Therapeutic Target For Non-Hodgkin Lymphoma

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1300-1300
Author(s):  
Yuankai Shi ◽  
Jianfei Wang ◽  
Xiaohong Han ◽  
Ningning Zhang ◽  
Shuai Wang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Antitumor Activity ◽  
Cell Lines ◽  
Nuclear Export ◽  
Conflicts Of Interest ◽  
Human Lymphocytes ◽  
Xenograft Model ◽  
Lymphoma Cells

Abstract Background The nuclear export protein chromosomal region maintenance 1 (CRM1) may play a role in human neoplasia and serve as a novel target for cancer treatment. Investigators recently developed orally bioavailable selective inhibitors of nuclear export (SINEs) that irreversibly bind to CRM1 and block its function. Our objective was to evaluate the therapeutic efficacy of the novel SINEs KPT-185 and KPT-276 against NHL in vitro and in vivo and elucidate the mechanism of CRM1 inhibitor-mediated antitumor activity. Methods Cell viability, apoptosis and cell cycle were evaluated in 8 B and T cell lymphoma cell lines (Jeko-1, Mino, Granta519, Sp53, RL, Hut102, Hut78 and Jurkat) which were treated with KPT-185; Primary tumor cells from 5 patients and normal human lymphocytes from 2 healthy volunteers were treated directly with KPT-185. Tumor suppressor proteins were detected by western blot to explore the possible mechanisms of KPT-185 inducing lymphoma cells growth inhibition and apoptosis. BALB/c nude mice bearing Jeko-1 tumors were treated orally with KPT-276 (similar structure to KPT-185, but improved animal pharmacokinetics) to examine the efficacy and side-effects of KPT-276. Results KPT-185 displayed potent antiproliferative properties at submicromolar concentrations (half-maximal inhibitory concentrations, 60-120 nM) and induced cell-cycle arrest and apoptosis in NHL cell lines and normal lymphocytes. The antitumor activity mainly consisted of regulating cell growth and apoptosis mechanisms by inducing caspase cleavage and downregulating the expression of antiapoptotic proteins such as CRM1, nuclear factor-kB, and survivin. Furthermore, oral administration of KPT-276 significantly suppressed tumor growth and prolonged survival in mice with NHL xenografts without any major toxic effects (P < 0.001). Analysis of tumor remnants in the mice demonstrated that KPT-276 trapped the antiapoptoic protein survivin within the nuclei of NHL cells. Conclusions We observed the biologic and pharmacologic activity of CRM1-inhibiting SINEs in NHL cells, primary NHL tumor samples, and a murine NHL xenograft model. SINE CRM1 inhibitors inhibited growth of lymphoma cells both in vitro and in vivo. The antitumor activity of the SINEs resulted primarily from induction of caspase activity and downregulation of expression of antiapoptoic proteins such as survivin and NF-kB. The preclinical in vitro and in vivo results reported herein support further study of CRM1-inhibiting SINEs as novel therapeutics for NHL. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Edelfosine nanoemulsions inhibit tumor growth of triple negative breast cancer in zebrafish xenograft model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sofia M. Saraiva ◽  
Carlha Gutiérrez-Lovera ◽  
Jeannette Martínez-Val ◽  
Sainza Lores ◽  
Belén L. Bouzo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Tumor Growth ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
Xenograft Model ◽  
Skin Barrier ◽  
Zebrafish Embryos ◽  
Biorelevant Media

AbstractTriple negative breast cancer (TNBC) is known for being very aggressive, heterogeneous and highly metastatic. The standard of care treatment is still chemotherapy, with adjacent toxicity and low efficacy, highlighting the need for alternative and more effective therapeutic strategies. Edelfosine, an alkyl-lysophospholipid, has proved to be a promising therapy for several cancer types, upon delivery in lipid nanoparticles. Therefore, the objective of this work was to explore the potential of edelfosine for the treatment of TNBC. Edelfosine nanoemulsions (ET-NEs) composed by edelfosine, Miglyol 812 and phosphatidylcholine as excipients, due to their good safety profile, presented an average size of about 120 nm and a neutral zeta potential, and were stable in biorelevant media. The ability of ET-NEs to interrupt tumor growth in TNBC was demonstrated both in vitro, using a highly aggressive and invasive TNBC cell line, and in vivo, using zebrafish embryos. Importantly, ET-NEs were able to penetrate through the skin barrier of MDA-MB 231 xenografted zebrafish embryos, into the yolk sac, leading to an effective decrease of highly aggressive and invasive tumoral cells’ proliferation. Altogether the results demonstrate the potential of ET-NEs for the development of new therapeutic approaches for TNBC.

scholarly journals ID: 1023 All-trans retinoic acid targets gastric cancer stem cells and inhibits patient-derived gastric carcinoma tumor growth

2017 ◽  
Vol 4 (S) ◽  
pp. 98
Author(s):  
P H Nguyen ◽  
J Giraud ◽  
C Staedel ◽  
L Chambonnier ◽  
P Dubus ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Stem Cells ◽  
Cancer Stem Cells ◽  
Gastric Carcinoma ◽  
Tumor Growth ◽  
Cell Cycle Progression ◽  
3D Culture ◽  
All Trans Retinoic Acid

Gastric carcinoma is the third leading cause of cancer-related death worldwide. This cancer, most of the time metastatic, is essentially treated by surgery associated with conventional chemotherapy, and has a poor prognosis. The existence of cancer stem cells (CSC) expressing CD44 and a high aldehyde dehydrogenase (ALDH) activity has recently been demonstrated in gastric carcinoma and has opened new perspectives to develop targeted therapy. In this study, we evaluated the effects of all-transretinoic acid (ATRA) on CSCs in human gastric carcinoma. ATRA effects were evaluated on the proliferation and tumorigenic properties of gastric carcinoma cells from patient-derived tumors and cell lines in conventional 2D cultures, in 3D culture systems (tumorsphere assay) and in mouse xenograft models. ATRA inhibited both tumorspheres initiation and growth in vitro, which was associated with a cell-cycle arrest through the upregulation of cyclin-dependent kinase (CDK) inhibitors and the downregulation of cell-cycle progression activators. More importantly, ATRA downregulated the expression of the CSC markers CD44 and ALDH as well as stemness genes such as Klf4 and Sox2 and induced differentiation of tumorspheres. Finally, 2 weeks of daily ATRA treatment were sufficient to inhibit gastric tumor progression in vivo, which was associated with a decrease in CD44, ALDH1, Ki67 and PCNA expression in the remaining tumor cells. Administration of ATRA appears to be a potent strategy to efficiently inhibit tumor growth and more importantly to target gastric CSCs in both intestinal and diffuse types of gastric carcinoma.

scholarly journals Tumor quiescence: elevating SOX2 in diverse tumor cell types downregulates a broad spectrum of the cell cycle machinery and inhibits tumor growth

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ethan P. Metz ◽  
Erin L. Wuebben ◽  
Phillip J. Wilder ◽  
Jesse L. Cox ◽  
Kaustubh Datta ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Tumor Growth ◽  
Tumor Cell ◽  
Tumor Cells ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Cell Cycle Machinery

Abstract Background Quiescent tumor cells pose a major clinical challenge due to their ability to resist conventional chemotherapies and to drive tumor recurrence. Understanding the molecular mechanisms that promote quiescence of tumor cells could help identify therapies to eliminate these cells. Significantly, recent studies have determined that the function of SOX2 in cancer cells is highly dose dependent. Specifically, SOX2 levels in tumor cells are optimized to promote tumor growth: knocking down or elevating SOX2 inhibits proliferation. Furthermore, recent studies have shown that quiescent tumor cells express higher levels of SOX2 compared to adjacent proliferating cells. Currently, the mechanisms through which elevated levels of SOX2 restrict tumor cell proliferation have not been characterized. Methods To understand how elevated levels of SOX2 restrict the proliferation of tumor cells, we engineered diverse types of tumor cells for inducible overexpression of SOX2. Using these cells, we examined the effects of elevating SOX2 on their proliferation, both in vitro and in vivo. In addition, we examined how elevating SOX2 influences their expression of cyclins, cyclin-dependent kinases (CDKs), and p27Kip1. Results Elevating SOX2 in diverse tumor cell types led to growth inhibition in vitro. Significantly, elevating SOX2 in vivo in pancreatic ductal adenocarcinoma, medulloblastoma, and prostate cancer cells induced a reversible state of tumor growth arrest. In all three tumor types, elevation of SOX2 in vivo quickly halted tumor growth. Remarkably, tumor growth resumed rapidly when SOX2 returned to endogenous levels. We also determined that elevation of SOX2 in six tumor cell lines decreased the levels of cyclins and CDKs that control each phase of the cell cycle, while upregulating p27Kip1. Conclusions Our findings indicate that elevating SOX2 above endogenous levels in a diverse set of tumor cell types leads to growth inhibition both in vitro and in vivo. Moreover, our findings indicate that SOX2 can function as a master regulator by controlling the expression of a broad spectrum of cell cycle machinery. Importantly, our SOX2-inducible tumor studies provide a novel model system for investigating the molecular mechanisms by which elevated levels of SOX2 restrict cell proliferation and tumor growth.

scholarly journals MNAT1 promotes proliferation and the chemo-resistance of osteosarcoma cell to cisplatin through regulating PI3K/Akt/mTOR pathway

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Chensheng Qiu ◽  
Weiliang Su ◽  
Nana Shen ◽  
Xiaoying Qi ◽  
Xiaolin Wu ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Xenograft Model ◽  
Mtor Pathway ◽  
Regulation Mechanism ◽  
Osteosarcoma Cell ◽  
Migration Ability ◽  
Mouse Xenograft Model

Abstract Background MNAT1 (menage a trois 1, MAT1), a cyclin-dependent kinase-activating kinase (CAK) complex, highly expressed in diverse cancers and was involved in cancer molecular pathogenesis. However, its deliverance profile and biological function in osteosarcoma (OS) remain unclear. Methods The expression of MNAT1 in OS was detected by western blot (WB) and immunohistochemistry (IHC). The potential relationship between MNAT1 molecular level expression and OS clinical expectations were analyzed according to tissues microarray (TMA). Proliferation potential of OS cells was evaluated in vitro based on CCK8 and OS cells colony formation assays, while OS cells transwell and in situ tissue source wound healing assays were employed to analyze the OS cells invasion and migration ability in vitro. A nude mouse xenograft model was used to detect tumor growth in vivo. In addition, ordinary bioinformatics analysis and experimental correlation verification were performed to investigate the underlying regulation mechanism of OS by MNAT1. Results In this research, we found and confirmed that MNAT1 was markedly over-expressed in OS tissue derived in situ, also, highly MNAT1 expression was closely associated with bad clinical expectations. Functional studies had shown that MNAT1 silencing could weaken the invasion, migration and proliferation of OS cells in vitro, and inhibit OS tumor growth in vivo. Mechanism study indicated that MNAT1 contributed to the progression of OS via the PI3K/Akt/mTOR pathway. We further verified that the MNAT1 was required in the regulation of OS chemo-sensitivity to cisplatin (DDP). Conclusions Taken together, the data of the present study demonstrate a novel molecular mechanism of MNAT1 involved in the formation of DDP resistance of OS cells.

scholarly journals TRIM33 Overexpression Inhibits the Progression of Clear Cell Renal Cell Carcinoma In Vivo and In Vitro

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Yingkun Xu ◽  
Guangzhen Wu ◽  
Jiayao Zhang ◽  
Jianyi Li ◽  
Ningke Ruan ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Mrna Expression ◽  
Wnt Signaling Pathway ◽  
Xenograft Model ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Cell Renal Cell Carcinoma ◽  
Expression Levels

Purpose. To evaluate the expression of tripartite motif-containing 33 (TRIM33) in ccRCC tissues and explore the biological effect of TRIM33 on the progress of ccRCC. Method. The Cancer Genome Atlas (TCGA) database was used to examine the mRNA expression levels of TRIM33 in ccRCC tissues and its clinical relevance. Immunohistochemistry (IHC) was performed to evaluate its expression in ccRCC tissues obtained from our hospital. The correlation between TRIM33 expression and clinicopathological features of the patients was also investigated. The effects of TRIM33 on the proliferation of ccRCC cells were examined using the CCK-8 and colony formation assays. The effects of TRIM33 on the migration and invasion of ccRCC cells were explored through wound healing and transwell assays, along with the use of Wnt signaling pathway agonists in rescue experiments. Western blotting was used to explore the potential mechanism of TRIM33 in renal cancer cells. A xenograft model was used to explore the effect of TRIM33 on tumor growth. Result. Bioinformatics analysis showed that TRIM33 mRNA expression in ccRCC tissues was downregulated, and low TRIM33 expression was related to poor prognosis in ccRCC patients. In agreement with this, low TRIM33 expression was detected in human ccRCC tissues. TRIM33 expression levels were correlated with clinical characteristics, including tumor size and Furman’s grade. Furthermore, TRIM33 overexpression inhibited proliferation, migration, and invasion of 786-O and ACHN cell lines. The rescue experiment showed that the originally inhibited migration and invasion capabilities were restored. TRIM33 overexpression reduced the expression levels of β-catenin, cyclin D1, and c-myc, and inhibited tumor growth in ccRCC cells in vivo. Conclusion. TRIM33 exhibits an abnormally low expression in human ccRCC tissues. TRIM33 may serve as a potential therapeutic target and prognostic marker for ccRCC.

scholarly journals ABCG2-overexpressing H460/MX20 cell xenografts in athymic nude mice maintained original biochemical and cytological characteristics

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Wei Zhang ◽  
Zhen Chen ◽  
Likun Chen ◽  
Fang Wang ◽  
Furong Li ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Nude Mice ◽  
Large Cell ◽  
Athymic Nude Mice ◽  
H460 Cell ◽  
Large Cell Lung Cancer ◽  
Cytological Characteristics

Abstract H460/MX20 are derived from large cell lung cancer H460 cell line and then transformed into ABCG2-overexpressing cells by mitoxantrone’s induction, which are widely used in study of multidrug resistance (MDR) in vitro. To establish and spread the model of H460/MX20 cell xenografts, we investigated whether cell biological characteristics and the MDR phenotype were maintained in vivo model. Our results demonstrated that the cell proliferation, cell cycle, and ABCG2 expression level in xH460/MX20 cells isolated from H460/MX20 cell xenografts were similar to H460/MX20 cells in vitro. Importantly, xH460/MX20 cells exhibited high levels of resistance to ABCG2 substrates such as mitoxantrone and topotecan as H460/MX20 cells did. Furthermore, lapatinib, the inhibitor of ABCG2, potently reversed mitoxantrone- and topotecan-resistance of xH460/MX20 cells. Taken together, these results suggest that H460/MX20 cell xenografts in athymic nude mice still retain their original cytological characteristics and MDR phenotype. Thus, the H460/MX20 cell xenografts model could serve as a sound model in vivo for study on reversal MDR.

Thrombin Enhances Spontaneous Tumor Growth and Cell Cycle Activation by Downregulation of p27Kip1 and Upregulation of Skp2 and MiR-222

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 396-396
Author(s):  
Liang Hu ◽  
Sherif Ibrahim ◽  
Cynthia Liu ◽  
Jeffrey Skaar ◽  
Michelle Pagano ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Growth Factors ◽  
Cell Growth ◽  
Tumor Growth ◽  
Tumor Cell ◽  
Tumor Volume ◽  
S Phase ◽  
Down Regulation

Abstract Although it has been generally accepted that hypercoagulability contributes to enhancing tumor growth via generation of thrombin (Cancer Cell10:355, 2006), it has not been rigorously proven, nor has the mechanism been established at the cell cycle level. Previous studies have employed thrombin-treated tumor cell lines in vitro and in vivo. In vitro studies were performed in the presence of serum which contains a panoply of growth factors. In vivo studies have used huge non-pathologic concentrations of tumor cells injected into the flank, organ or blood of a mouse. In these situations, tumor growth could be a result of thrombin-induced angiogenesis. We therefore employed a transgenic mouse prostate cancer model (TRAMP) programmed to develop prostate CA over a period of 140–175 days. We treated these animals with thrombin to induce hypercoagulability or hirudin to inhibit endogenous thrombin production, to determine whether thrombin regulates this process independent of angiogenesis. Repetitive thrombin injection enhanced prostate tumor volume 6–8 fold (p&lt;0.04). Repetitive hirudin decreased tumor volume 13–24 fold (p&lt;0.04) via its effect on generated endogenous thrombin, n=6. Thrombin enhanced the production of several vascular growth factors and receptors 2.5 – 3 fold in the liver (VEGF, KDR, ANG-2, Tie2, GRO-1, CD31) and enhanced angiogenesis in the liver, n=3–4. Thrombin had no effect on tumor angiogenesis. Thus, the thrombin-induced spontaneous tumor growth was independent of angiogenesis. We next turned our attention to cell cycle regulators in serum-starved (72 hr) Go-synchronized LNcap prostate CA cells, employing Brdu and Propidium iodide staining. Addition of thrombin (0.5 u/ml) or its PAR-1 receptor agonist, TFLLRN (100 uM) had the same effect as androgen containing serum, inducing cells to leave Go, enter G1 and progress to S-phase. At 8 hrs the number of S-phase cells increased dramatically for both the serum (29 fold) as well as thrombin-treated cells (48 fold), n=3. Similar observations were noted in a Glioblastoma cell line, T98G. We further analyzed the effect of thrombin by performing immunoblots on cell cycle components mediated during cell growth and proliferation. In synchronized Go cells, levels of p27Kip1, a cyclin-dependent kinase inhibitor are high, while levels of cyclins D1 and A, the activation subunits for cyclin-dependent kinases are low. Both thrombin or serum addition led to down-regulation of p27Kip1 with concomitant induction of Skp2, the E3 ubiquitin ligase for p27Kip1. Cyclins D1 and A are induced by similar kinetics, indicating entry into S-phase by 8 hrs. Since p27Kip1 appears to be a rate-limiting down-regulator of the cell cycle (absent with high tumor grade and predicts poor prognosis), we confirmed its role by testing the effect of thrombin or TFLLRN by transfecting p27Kip1 in LNcap cells. This transfection completely prevented the cell cycle stimulation induced by these agonists. A similar approach was used with Skp2 knock down (KD), a negative down-regulator of p27Kip1. KD of Skp2 (over expressed in numerous cancers) completely prevented cell cycle progression induced by thrombin/TFLLRN. MiRNA 222 (upregulated in many cancers) is another down-regulator of p27Kip1. Further analysis following thrombin treatment revealed a robust upregulation at 4 and 8 hrs, providing further proof for the role of thrombin in down-regulating p27Kip1 and stimulating tumor cell entrance into S-phase. Thus, 1) Thrombin enhances spontaneous prostate cell growth in vivo in the absence of enhanced angiogenesis; 2) Thrombin activates the tumor cell cycle by stimulating the down-regulation of p27Kip1 through the upregulation of Skp2 and MiRNA 222.

New targeted anti CDK4/6 peptide MM-D37K.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. e13545-e13545 ◽  
Author(s):  
Vladimir Konstantinovich Bozhenko ◽  
Tatyana Michailovna Kulinich ◽  
Elena Aleksandrovna Kudinova ◽  
Andrey Boldyrev ◽  
Vladimir Alekseevich Solodkij
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Full Range ◽  
Mrna Level ◽  
Xenograft Model ◽  
Specific Inhibitor ◽  
Antitumor Effects ◽  
Mcf 7

e13545 Background: MM-D37K is a synthetic peptide which consists of p16INK4a-specific inhibitor of complex cyclin D- CDK4 and CDK6 and cell penetrating peptide (CPP) – Antp (Penetratin). We investigated in vitro and in vivo cytotoxic, cytostatic and antitumor activity of MM-D37K. The level of cyclin A, Ki67,bax, bcl-2 and pRb phosphorylation was investigated. Full range of Toxicology tests and Pharmacokinetics experiments in mice, rats and rabbits were performed. Methods: Different cell lines (Jurcat, Raji, A549, MCF-7, Hct-116, Ht-29, HEK293) were incubated with 0.1-100 mM MM-D37K for 24-48 hrs. Proliferation (MTT), DNA-content, cell cycle (flow cytometry) and mRNA level of appropriate proteins (RT PCR) were investigated. In vivo experiments were conducted on xenograft model of HCT116, A-549 at concentration 5 and 10 mg/kg of MM-D37K. Toxicology experiments were made under RF Law and included 3 types of animals. LC-MS MMD37K method of detection in plasma was developed. Results: MM-D37K prevented pRb phosphorilation and proliferation activation in all investigated cell lines. Cell cycle was blocked in G1 phase. Cytostatic effect did not depend on p16 mutation or expression. MM-D37K induced apoptosis in 20-82% of investigated cells at 40 mM with lowest level for MCF-7. LD10 for rats was 100 mg/kg and no deaths were registered for rabbits (highest dose was 50 mg/kg). Concentration of MMD-37K in plasma after 2 min and bolus i.v. injection in dose 10 mg/kg was 72.16±5.64 mcg/ml. Concentration decreased in two phases. 1st – t1/2 = 2.39±0.39 min and for 2nd t1/2=2.39±0.39 hr. Antitumor effects in xenograft model were 53% for A-549 and 67% for HCT116. Conclusions: Our results proved cytotoxic, cytostatic and antitumor effects of MM-D37K in investigated cell lines in vitro and in vivo. Toxicological and pharmacokinetics results allow us recommend for I/IIa Phase clinical trial. (Support: MetaMax Ltd., RFFI, Minpromtorg RF.)

Modulation of the anti-tumor activity of VEGF blockade by metformin.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e23009-e23009
Author(s):  
Mohamed Selmy ◽  
Elisabetta Zulato ◽  
Anna Pasto ◽  
Stefano Indraccolo
Keyword(s):  
Cell Cycle ◽  
Tumor Growth ◽  
Glucose Deprivation ◽  
Potential Candidate ◽  
Ampk Activation ◽  
Proliferative Capacity ◽  
Combination Strategy ◽  
Mtor Inhibition

e23009 Background: The payoff from first-generation angiogenesis inhibitors was commonly temporary, due to the development of intrinsic as well as acquired resistance. Apart from the vascular resistance due to circumventing VEGF blockade by proangiogenic factors, resistance has also been associated with assortment of resistant clones. Accordingly, a combination strategy was proposed to overcome such resistance. Metformin, as a potential candidate, has received considerable concern as an anticancer agent. Methods: IN-VITRO WORK;Cells were divided into normoxic and hypoxic groups. For both, four subgroups were developed; control, metformin, glucose deprivation and a subgroup in which cells were subjected to both glucose deprivation and metformin treatment. Cells were then subjected to analysis for Apoptosis, Cell cycle progression and western blot. IN-VIVO WORK; Tumor growth was assessed IGROV-1 subcutaneous xenografts. Animal were divided into four groups; control, Metformin, Bevacizumab and a fourth group receiving both drugs. Tumor growth was assessed along treatments and at time of sacrifice.After sacrificing animals, tumors were further analyzed for; necrosis, apoptosis, proliferative capacity, activation of AMPK and its downstream effectors. Results: Our in-vitro results suggested an anti-proliferative effect of metformin in terms of apoptosis, cell cycle arrest, AMPK activation and mTOR inhibition at various time points. In-vivo experiments revealed a significant decrease of tumor weight and proliferative capacity in tumors treated with both drugs and a trend toward a decrease in tumor growth along the treatment. Yet, there was no difference between the bevacizumab and the combination groups regarding AMPK activation suggesting another mechanism to exert the combination effect. The effect of Metformin on CSC percentage and viability was tested. Glucose deprivation plus hypoxia lead to increase in CSC population, while adding metformin to bevacizumab reverse this augmentation in CSC numbers. Conclusions: Study represents a proof of concept study demonstrating a positive modulatory effect of metformin addition to bevacizumab. Additional experimental work on a wider scale is running to ascertain the current results.

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