23 research outputs found
Insulin-like growth factor-binding protein-2 promotes prostate cancer cell growth via IGF-dependent or -independent mechanisms and reduces the efficacy of docetaxel
Background: The development of androgen independence, chemo-, and radioresistance are critical markers of prostate cancer progression and the predominant reasons for its high mortality. Understanding the resistance to therapy could aid the development of more effective treatments. Aim: The aim of this study is to investigate the effects of insulin-like growth factor-binding protein-2 (IGFBP-2) on prostate cancer cell proliferation and its effects on the response to docetaxel. Methods: DU145 and PC3 cells were treated with IGFBP-2, insulin-like growth factor I (IGF-I) alone or in combination with blockade of the IGF-I receptor or integrin receptors. Cells were also treated with IGFBP-2 short interfering ribonucleic acid with or without a PTEN (phosphatase and tensin homologue deleted on chromosome 10) inhibitor or docetaxel. Tritiated thymidine incorporation was used to measure cell proliferation and Trypan blue cell counting for cell death. Levels of IGFBP-2 mRNA were measured using RT-PCR. Abundance and phosphorylation of proteins were assessed using western immunoblotting. Results: The IGFBP-2 promoted cell growth in both cell lines but with PC3 cells this was in an IGF-dependent manner, whereas with DU145 cells the effect was independent of IGF receptor activation. This IGF-independent effect of IGFBP-2 was mediated by interaction with β-1-containing integrins and a consequent increase in PTEN phosphorylation. We also determined that silencing IGFBP-2 in both cell lines increased the sensitivity of the cells to docetaxel. Conclusion: The IGFBP-2 has a key role in the growth of prostate cancer cells, and silencing IGFBP-2 expression reduced the resistance of these cells to docetaxel. Targeting IGFBP-2 may increase the efficacy of docetaxel.7 page(s
Loss of PTEN expression is associated with IGFBP2 expression, younger age, and late stage in triple-negative breast cancer
© American Society for Clinical Pathology. Objectives: To investigate the association between PTEN loss and IGFBP2 expression in a series of triple-negative breast cancers and to relate this expression to basal cytokeratin expression and clinicopathologic features. Methods: One hundred and one formalin-fixed and paraffin-processed triple-negative breast cancer cases from the University of Malaya Medical Centre were tested immunohistochemically for cytokeratins 5/6 and 14, PTEN, and IGFBP2. The resulting slides were scored for proportion and intensity of staining. Results: Loss of tumor nuclear and cytoplasmic staining for PTEN occurred in 48.3% of cases and was significantly associated with younger age at diagnosis (47 years compared with 57 years in those without PTEN loss; P = .005). Independent predictors of PTEN loss were late stage at presentation ( P = .026), cytokeratin 5/6 positivity ( P = .028), and IGFBP2 expression ( P = .042). High levels of IGFBP2 expression were seen in 32% of cases; an independent predictor of high levels was cytokeratin 14 negativity ( P = .005). PTEN loss and high levels of IGFBP2 expression were associated with poorer survival, but neither of these trends was significant. Conclusions: PTEN loss is a frequent event in triple-negative breast cancers and is significantly associated with younger age at onset of breast cancer, late stage, and IGFBP2 expression
Bone and prostate cancer cell interactions in metastatic prostate cancer
The interplay in prostate cancer bone metastases between the 'seed' (the prostate cancer cells) and the 'soil' (the bone microenvironment) has been increasingly recognized as integral to the remarkable tropism for bone shown by prostate cancer. Increasing research into this area is elucidating the mechanisms involved in this complex 'cross-talk'. Recent developments, including the use of bisphosphonates in metastatic disease, highlight the important role of bone cells in the development and progression of metastatic prostate cancer. We review the current reports emphasising these possible mechanisms and indicating possible factors for future treatment directions
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The Impact Of Higher Order Questioning Based On Commercial Tv Shows Upon The Critical Thinking Skills Of Fifth Grade Elementary School Children
Purpose. This study was developed to explore: (1) the effect of higher order questions based on commercial television programs upon the critical thinking skills of fifth graders. (2) whether the effect produced from a treatment of six questions was different from that produced from twelve questions. (3) whether the effect of questions based on drama programs was different from that based upon comedy programs.Research has acknowledged the pervasive nature of television in the lives of children. Yet, no studies have explored the way in which higher order thinking questions based on commercial television programs can effect the critical thinking skills of children.Procedure. There were 100 fifth graders randomly assigned to one of six groups. Two groups were asked 12 questions and two groups were asked six questions, following their viewing of a specific program. The questions asked were designed to stimulate higher order thinking skills. The remaining two groups were given assignments which required no stimulation of higher cognitive skills. Half of all the subjects viewed comedy programs and half viewed drama programs. The groups were visited for one hour per week for six weeks. The Ross Test of Higher Cognitive Processes was then administered. An analysis of variance with planned comparisons was performed.Findings. Based on three a priori comparisons, tested at the .05 level, the following was obtained: (1) A positive relationship exists between treatments and scores on the Ross Test when treatment groups were combined for analysis (p .05). (3) No difference exists between the performance of the groups based on the type of programs upon which questions were based (p \u3e .05).Conclusions. The use of higher order questions, based on commercial television programs, has a positive effect upon the critical thinking skills of those tested. Parents and educators can use the motivating nature of television to help stimulate the cognitive skills of children through questioning
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Evaluation of analgesic requirements and postoperative recovery after radical retropubic prostatectomy using long-acting spinal anesthesia
To analyze the postoperative pain, analgesic requirements, and convalescence of patients undergoing radical retropubic prostatectomy (RRP) under spinal anesthesia using long-acting morphine sulfate as preemptive analgesia.
A total of 103 consecutive men underwent RRP by a single surgeon. The time to tolerate oral fluids, time to unassisted ambulation, postoperative pain levels (visual analog pain score of 0 to 10), and analgesic requirements expressed in morphine equivalents were evaluated. Baseline patient characteristics and intraoperative factors (operating room time, blood loss) were also evaluated.
The mean time to tolerate oral fluids and unassisted ambulation was 11.3 +/- 7.6 hours and 20 +/- 6 hours, respectively. The mean narcotic requirements were 7.4 +/- 6.1 morphine equivalents before discharge and 28.5 +/- 25.9 morphine equivalents in the first week after discharge. The mean visual analog pain score was 4.5 +/- 2.1 at discharge and fell significantly to 1.5 +/- 1.0 by the time of Foley catheter removal on postoperative day 7 or 8. The analgesic requirements after discharge correlated with the pain score at discharge (P = 0.016). The mean time to resumption of normal preoperative activities was 19.4 +/- 9.4 days. Two patients developed postspinal anesthesia headache. No other complications attributable to the anesthetic occurred.
RRP may be performed through a small modified Pfannenstiel incision under spinal anesthesia containing long-acting morphine with little postoperative pain, low narcotic requirements, and a short convalescence. A prospective, randomized study is needed to compare the early postoperative outcomes of RRP performed using general versus spinal anesthesia
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Interleukin-8 is a molecular determinant of androgen independence and progression in prostate cancer
Multiplexed electrochemical cancer diagnostics with automated microfluidics
Microfluidic platforms can lead to miniaturisation, increased throughput and reduced reagent consumption, particularly when the processes are automated. Here, a programmable microcontroller is used for automation of a microfluidic platform configured to electrochemically determine the levels of 8 proteins simultaneously in complex liquid samples. The platform system is composed of a programmable Arduino microcontroller that controls inexpensive valve actuators, pump, magnetic stirrer and electronic display. The programmable microcontroller results in repeatable timing for each step in a complex assay protocol, such as sandwich immunoassays. Application of the platform is demonstrated using a multiplexed electrochemical immunoassay based on capture at the electrode surface of magnetic particles labelled with horseradish peroxidase and detection antibody. The multiplexed assay protocol is completed in less than 30 mins and results in detection of eight proteins associated with prostate cancer. The approach presented can be used to automate and simplify high‐throughput screening campaigns, such as detection of multiple biomarkers in patient samples.This work was supported financially by US‐Ireland Program (Grant Number EB014586) administered by the National Institute of Biomedical Imaging and Bioengineering (NIBIB), and funded by NIH and Science Foundation Ireland under the US/Ireland programme (Grant Number 13/US/B2546). The authors are grateful to Dr. Colleen Krause and Dr. Brunah Otieno for sharing details on the original non‐automated microfluidic immunoarray.2019-11-2