Pioglitazone alters monocyte populations and stimulates recent thymic emigrants in the BBDZR/Wor type 2 diabetes rat model

Peripheral lymphocyte subsets as predicting factors for molecular recurrence after imatinib discontinuation in a phase 2 imatinib discontinuation trial in patients with chronic myeloid leukemia

INTRODUCTION

Treatment-free remission (TFR) is successful in half of the patients with chronic myeloid leukemia who discontinue Imatinib (IM) after sustained molecular response.

METHODS

In a prospective trial, we used pioglitazone for 3 months before stopping IM in 30 patients. Percentages of peripheral blood lymphocyte subsets were assessed before and after treatment. The relation of these data with duration of IM treatment and TRF were examined.

RESULTS

The median time of IM treatment was 117.6 months. After discontinuation, 11 patients had molecular recurrence after 5.2 months (2.4 - 30). The observation time for those remaining in TFR was 46 (26 - 56) months. The independent factors for the maintenance of TFR were the duration of IM treatment and the percentage of double-positive T cells at IM stop.

CONCLUSION

A longer treatment with imatinib was associated with a longer TFR after discontinuation. Pioglitazone could act as an immunomodulator, increasing DP T cells which may contribute to prevent relapse.

Effects of adenosine N1-Oxide and pioglitazone on inflammatory and antioxidant state in sepsis caused by experimental cecal puncture in rat

Sepsis is an acute condition caused by the systemic inflammatory response syndrome to an infection. There are very few drugs that could improve the severe conditions in patients with sepsis. Hence, it is important to consider different treatment options. In this survey, we studied the effect of adenosine N1-oxide (ANO) and pioglitazone on rats with cecal ligation and perforation (CLP). They were randomly divided to four groups (n = 10) including Group A: as control group receiving normal saline, Group B: the rats with CLP as surgical control group, Group C: the rats receiving ANO, and Group D: the rats receiving pioglitazone. Interleukin (IL) -6, IL-1β, tumor necrosis factor alpha (TNF-α), nitric-oxide (NO) in serum blood and superoxide dismutase (SOD), catalase (CAT) malondialdehyde, (MDA) and myeloperoxidase (MPO) in liver and spleen homogenates were measured. The amount of antioxidant enzymes in the spleen and liver, and finally cell viability and rats' survival were investigated. The measurement of blood serum nitric-oxide and survival of all groups of rats were also performed. The results indicated that both drugs could cause a decrease in IL-1β, IL-6, TNF-α and NO in rat blood serum and MDA and MPO in the liver and spleen homogenates, however, a significant increase in SOD and CAT in the liver and spleen homogenates in rats that received ANO and pioglitazone was observed compared to rats with CLP group. Cell viability and rats' survival were significantly improved in rats that received ANO and pioglitazone compared to rats with CLP group. Adenosine N1-oxide showed stronger and more effective effects.

Natural killer cells and pigment epithelial-derived factor control the infiltrative and nodular growth of hepatic metastases in an Orthotopic murine model of ocular melanoma

Background

Metastases account for 90% of all cancer-related deaths, becoming a therapeutic problem. Approximately 50% of all uveal melanoma (UM) patients will develop metastases, mainly in the liver. Post-mortem analyses of livers from metastatic UM patients showed two different metastatic growth patterns: infiltrative and nodular. The infiltrative pattern exhibits tumor infiltration directly to the hepatic lobule and minimal angiogenesis. The nodular pattern shows clusters of tumor cells around the portal venules that efface the liver parenchyma. We recently demonstrated Natural Killer (NK) cells play a pivotal role in the control of hepatic metastases and the pigment epithelial-derived factor (PEDF) controls angiogenesis in the liver using our established ocular melanoma animal model. In this study we investigated the role of NK cells and PEDF in the development of metastatic growth patterns, as this can contribute to the development of novel therapeutics specific towards each growth pattern.

Methods

We utilize our established ocular melanoma animal model by inoculation of B16-LS9 melanoma cells into C57BL/6 J mice (WT), anti-asialo GM1-treated C57BL/6 J mice (NK-depleted), and PEDF^−/− C57BL/6 J mice. Three weeks after inoculation we evaluated the metastatic growth patterns and stratified them based of the numbers of tumor cells. To evaluate angiogenesis the mean vascular density (MVD) was calculated. The immune compartment of the liver was analyzed by flow cytometry.

Results

Our in vivo work showed two distinct metastatic growth patterns, the infiltrative and nodular, recapitulating the post-mortem analyses on human liver tissue. We discovered NK cells control the infiltrative growth. In contrast, PEDF controlled anti-angiogenic responses, showing higher MVD values compared to NK-depleted and WT animals. The myeloid lineage, comprised of monocytes, macrophages, and myeloid-derived suppressor cells, was reduced in the absence of NK cells or PEDF.

Conclusions

Our animal model recapitulates the metastatic growth patterns observed in the human disease. We demonstrated a role for NK cells in the development of the infiltrative growth pattern, and a role for PEDF in the development of the nodular pattern. The understanding of the complexity associated with the metastatic progression has profound clinical implications in the diagnostic and disease-management as we can develop and direct more effective therapies.

Impact of Metformin and Pioglitazone on Serum Level of Tumor Necrosis Factor-Alpha and Lipid Profiles during Implantation Window in Diabetic Rats

Background

The present study was designed to evaluate serum lipid profile and tumor necrosis factor-alpha (TNF-ɑ) level in diabetic rats at implantation time. Type 2 diabetes mellitus (T2DM) could affect various systems, including innate immune system and it causes chronic low-grade inflammation, increasing level of TNF-ɑ. Furthermore, T2DM is often accompanied by impaired lipid profile. Metformin and pioglitazone are used as the first and second lines of treatment for T2DM.

Materials and Methods

In this experimental study, 35 adult virgin female wistar rats, weighting 175-225 g, were randomly categorized into five groups: i. Control, ii. Sham, iii. Nicotinamide (NA)+streptozotocin (STZ) induced T2DM, iv. Diabetic+pioglitazone (20 mg/kg/day for 28 days oral administration), and v. Diabetic+metformin (100 mg/kg/day for 28 days oral administration). At the time of implantation, TNF-ɑ level in serum of rats was measured by ELISA kit. Glucose was measured using photometric method and lipid profiles were calculated by enzymatic methods.

Results

Level of TNF-ɑ in the diabetic group was significantly higher than other groups (P<0.001). In metformin treated group, TNF-ɑ serum level was also significantly higher than pioglitazone treated group (P<0.001). Fasting blood sugar (FBS) and lipid profiles were significantly higher in diabetic group.

Conclusion

Metformin and pioglitazone have similar effects on glucose, lipid profiles and TNF-ɑ serum levels. Among these drugs, pioglitazone has more efficient influence on TNF-α serum level, in comparison with metformin.

Targeting the Platelet-Derived Growth Factor-beta Stimulatory Circuitry to Control Retinoblastoma Seeds

Purpose

Vitreous seeding remains the primary reason for treatment failure in eyes with retinoblastoma (Rb). Systemic and intra-arterial chemotherapy, each with its own inherent set of complications, have improved salvage rates for eyes with advanced disease, but the location and biology of vitreous seeds present a fundamental challenge in developing treatments with minimal toxicity and risk. The aim of this study was to target the platelet-derived growth factor (PDGF)- PDGF-receptor β (PDGFRβ) signaling pathway and investigate its role in the growth of Rb seeds, apoptotic activity, and invasive potential.

Methods

We performed ex vivo analyses on vitreous samples from Rb patients that underwent enucleation and from patient-derived xenografts. These samples were evaluated by quantitative PCR, immunohistochemistry, and ELISA. The effects of disruption of the PDGF-PDGFRβ signaling pathway, both by pharmacologic and genomic knockdown approaches, were evaluated in vitro by cell proliferation and apoptotic assays, quantitative PCR analyses, Western blotting, flow cytometry, and imaging flow cytometry. A three-dimensional cell culture system was generated for in-depth study of Rb seeds.

Results

Our results demonstrated that PDGFRβ signaling is active in the vitreous of Rb patients and patient-derived xenografts, sustaining growth and survival in an AKT-, MDM2-, and NF-κB-dependent manner. The novel three-dimensional cell culture system mimics Rb seeds, as the in vitro generated spheroids have similar morphologic features to Rb seeds and mimicked their natural physiology.

Conclusions

Targeting the PDGFRβ pathway in vitro reduces Rb cell growth, survival, and invasiveness and could augment current therapies. This represents a novel signaling pathway for potential targeted therapy to further improve ocular survival in advanced Rb.

Inhibition of MMP-2 and MMP-9 decreases cellular migration, and angiogenesis in in vitro models of retinoblastoma

BACKGROUND

Retinoblastoma (Rb) is the most common primary intraocular tumor in children. Local treatment of the intraocular disease is usually effective if diagnosed early; however advanced Rb can metastasize through routes that involve invasion of the choroid, sclera and optic nerve or more broadly via the ocular vasculature. Metastatic Rb patients have very high mortality rates. While current therapy for Rb is directed toward blocking tumor cell division and tumor growth, there are no specific treatments targeted to block Rb metastasis. Two such targets are matrix metalloproteinases-2 and -9 (MMP-2, -9), which degrade extracellular matrix as a prerequisite for cellular invasion and have been shown to be involved in other types of cancer metastasis. Cancer Clinical Trials with an anti-MMP-9 therapeutic antibody were recently initiated, prompting us to investigate the role of MMP-2, -9 in Rb metastasis.

METHODS

We compare MMP-2, -9 activity in two well-studied Rb cell lines: Y79, which exhibits high metastatic potential and Weri-1, which has low metastatic potential. The effects of inhibitors of MMP-2 (ARP100) and MMP-9 (AG-L-66085) on migration, angiogenesis, and production of immunomodulatory cytokines were determined in both cell lines using qPCR, and ELISA. Cellular migration and potential for invasion were evaluated by the classic wound-healing assay and a Boyden Chamber assay.

RESULTS

Our results showed that both inhibitors had differential effects on the two cell lines, significantly reducing migration in the metastatic Y79 cell line and greatly affecting the viability of Weri-1 cells. The MMP-9 inhibitor (MMP9I) AG-L-66085, diminished the Y79 angiogenic response. In Weri-1 cells, VEGF was significantly reduced and cell viability was decreased by both MMP-2 and MMP-9 inhibitors. Furthermore, inhibition of MMP-2 significantly reduced secretion of TGF-β1 in both Rb models.

CONCLUSIONS

Collectively, our data indicates MMP-2 and MMP-9 drive metastatic pathways, including migration, viability and secretion of angiogenic factors in Rb cells. These two subtypes of matrix metalloproteinases represent new potential candidates for targeted anti-metastatic therapy for Rb.