Development of tumor-specific liposomes containing quantum dots-photosensitizer conjugate used for radiotherapy

This study aims to develop a multifunctional liposomal radiosensitizer to destroy more tumor cells by using lower radiation doses compared to clinically used 6 MV X-ray doses. To achieve this aim, first Chlorine-e6 (Ce6) was covalently bound to functional groups of outer surfaces of quantum dots (QDs) through EDC/NHS reactions. Then, QDs-Ce6 conjugate loaded, nanosized, PEG-coated, and tumor-specific folic acid-modified immunoliposome dispersions were prepared by film method. Enhanced anti-proliferation activity of free and liposomal conjugate against 4T1 (murine breast cancer) cell lines was investigated at different X-ray doses (5, 10, 15, and 20 Gy). As a result, the best radiosensitizer effect was observed at a 5 Gy X-ray dose and it was found that following the X-ray irradiation, immunoliposome dispersions containing QDs-Ce6 conjugate killed 26.8 ± 1.7% more cancer cells than radiation alone.

OP0026 IGF1R DEPENDENT CELL INTERACTION AND REGULATION OF AUTOANTIBODY PRODUCTION IN RHEUMATOID ARTHRITIS

Background:

The insulin-like growth factor 1 receptor (IGF1R) signalling mediates numerous developmental processes acting through downstream adaptor molecules IRS1/2, which activate Akt and inhibit the family of forkhead box class O (FoxO). Inhibition of IGF1R signalling alleviates rheumatoid arthritis (RA) (Erlandsson et al., 2017), however, the role of IGF1R signalling in the regulation of immune function is poorly understood.

Objectives:

To investigate the link between IGF1R signalling and antigen presentation in experimental arthritis.

Methods:

Arthritis was induced by immunising Balb/c mice with methylated bovine serum albumin (mBSA, n=18) and DBA/1 mice with type II collagen (CII, n=18). The mice were treated with a synthetic IGF1R inhibitor NT157 or with short hairpin RNA targeting IGF1R (shIGF1R) from the day prior to immunisation. Controls were treated with cyclodextrine vehicle/ non-targeting (nt)RNA, respectively. Flow cytometry was used for spleen cell phenotype. Antibody levels were measured by ELISA. Immunohistochemistry (IHC) of spleen was performed for assessment of marginal zone (MZ) and location of pS612IRS1+ and pS256FoxO1+ cells. IHC images were acquired by fluorescent confocal microscopy, and analysed using ZEN2009 and Cell Profiler soft ware.

Results:

The inhibition of IGF1R resulted in an 80% increase in MZ area in NT157-treated mice compared to controls (p=0.0001). This was supported by a significant increase of CD21+ (p=0.034) and CD23+ cell populations (p=0.00059), both among the CD19+ B cells and antigen-presenting MHCII+CD19- cells, implying that IGF1R expression regulates the populations of MZ and follicular cells. Additionally, there was a strong positive correlation between the decrease of IGF1R+ and ICOSL+ population on CD21+ cells (r=0.70, p=0.0071), which retained them in the MZ and prolonged communication with macrophages. Insufficient feedback from ICOSL- B cells limited expression of CXCR5 on CD4 cells. The IHC analysis displayed that, IGF1R inhibition led to abundance of inactivate pS612IRS1+ and pS256FoxO1+ cells within the MZ, compared with controls (p=0.0002). Alongside the increase of IgM+ B cell population (p=0.0022), we observed significant increase in number of antigen-presenting F4/80+ cells (p=0.043) and MARCO expression (p=0.043) after IGF1R intervention. Finally, the NT157- treated mice displayed a significant pleiotropic increase in IgM autoantibody production, with anti-CCP IgM (p=0.027), RF-IgM (p=0.0085), anti-DNA IgM (p=0.066) and in total IgM (p=0.027) levels, which correlated positively with pS256FoxO1+ cells (r=0.51, p=0.03). Levels of IgG were not changed.

Conclusion:

We show that IGF1R signalling is important for immune cell communication after antigen challenge. IGF1R controls ICOSL dependent trafficking of B cells through the MZ and facilitates interaction with T cells. Retention of B cells in the MZ tips the balance from T cell to macrophage-dependent processes, which permits the formation of autoantibody producing B cells.

References:

[1]Erlandsson, M., et.al., 2017. IGF-1R signalling contributes to IL-6 production and T cell dependent inflammation in rheumatoid arthritis. Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 1863(9), pp.2158-2170.

Disclosure of Interests:

None declared

Relationship of ozone application and time in rats with hypoxic-ischemic brain injury

BACKGROUND

Despite the important advances in pregnancy and newborn follow-up, hypoxic-ischemic encephalopathy is still one of the prominent causes of newborn mortality and disability worldwide, and there is no sufficiently effective treatment for it yet. This study aimed to investigate whether the ozone injection, administered in a single-dose as a preconditioning agent before the hypoxia and in single and repeated doses on different days following the hypoxia, would affect the spatial memory performance of the rats in the Morris water maze test or on their apoptotic cell numbers.

METHODS

The study consisted of 102 seven-day-old male Wistar baby rats randomly divided into five groups. Rats in all groups were induced with hypoxic-ischemic brain injury (HIBI) except for the Sham group, and 1.2 mg/kg ozone was administered intraperitoneally. For the apoptosis evaluation, eight rats from each of the first four groups were decapitated by cervical dislocation. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay was used for immunohistochemical quantification of apoptosis in the excised brains. Blood malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured in the blood samples collected through cardiac puncture. Fourteen-week-old rats underwent the Morris water maze test to test their long-term spatial memory.

RESULTS

On apoptotic quantification in the right hemisphere using the TUNEL assay, the numbers of apoptotic neurons in the ozone preconditioning group (Group 3) and the group given ozone on the day of hypoxia (Group 4) were found to be significantly higher than the Sham group (Group 1), but significantly lower than the non-treatment group (Group 2) (p <0.001; p <0.001, respectively). Group 3 rats had the highest mean MDA level and SOD activity. Considering the platform finding times in the first four days of the tests, Group 4 had the shortest times after Group 1; and on Day 4, Group 4 found the platforms significantly sooner than Groups 2, 3, and 5 (p <0.001). Comparison of Groups 1 and 4 revealed significantly shorter times for Group 1 for each day except for Day 2.

CONCLUSIONS

Other studies have shown that controlled application of ozone would result in oxidative preconditioning and reduce the damage induced by reactive oxygen species through enabling adaptation to oxidative stress. Our study obtained remarkable and encouraging findings for ozone administration in HIBI by examining Group 4's performance in the first four days and the difference in its platform finding times between Day 1 and Day 4. HIPPOKRATIA 2021, 25 (2):56-62.

Co-administration of apigenin with doxorubicin enhances anti-migration and antiproliferative effects via PI3K/PTEN/AKT pathway in prostate cancer cells

Prostate cancer is one of the leading cancers in men, and new approaches are needed for its treatment. The aim of this study was to investigate the effect of co-administration of naturally occurring flavone apigenin and doxorubicin to androgen-insensitive prostate cancer cells.

METHODS

The effect of the treatment on survival and migration of human PC3 cells was evaluated by MTT and scratch assay, respectively. Apoptosis and cell cycle distribution were detected by image-based cytometry. mRNA and protein expression were determined by real-time quantitative polymerase chain reaction and Western blot, respectively.

RESULTS

Apigenin and doxorubicin dose-dependently inhibited cell survival, and co-administration of both agents significantly induced cell death via upregulating the mRNA expression of caspases, Bax and cytochrome c, and downregulating Bcl-XL. Combination therapy caused cell cycle arrest by upregulating the expression of p21 and p27. The treatment modality inhibited cell migration via downregulating Snail, Twist and MMPs in which doxorubicin was ineffective. Apigenin dephosphorylated Akt strongly, significantly suppressed ERK phosphorylation, and increased PTEN expression 4.5-fold. The combination of apigenin and doxorubicin inhibited PI3K and AKT phosphorylation more strongly than a single administration.

CONCLUSIONS

Our data indicate that a combination of the natural flavone apigenin with doxorubicin might have a potential in treatment of castration-resistant prostate cancer.

The prognostic significance of the risk scores at upper gastrointestinal bleeding

Background

Upper gastrointestinal system (GIS) bleeding is one of the most common causes of mortality and morbidity. The predictive values of pre-endoscopic Rockall score (PERS), full Rockall score (FRS), Glasgow-Blatchford score (GBS), pre-endoscopic Baylor score (PEBS), and full Baylor score (FBS) to predict bleeding at follow-up, endoscopic therapy, blood transfusion requirement, and death are investigated in our study.

Methods

This study was retrospectively conducted in patients admitted to emergency department with upper GIS bleeding. Demographic and clinical characteristics of the patients were recorded. The relationships of the aforementioned scores with in-hospital termination, bleeding at follow-up, endoscopic therapy, blood transfusion requirement, and death were explored.

Results

The study included a total of 420 subjects, of which 269 (64%) were men. All scoring systems were able to predict transfusion need and GBS was superior to other scores (P < 0.0001). In terms of endoscopic treatment, it was determined that only PERS, FRS, and FBS were statistically significant in predicting ability and PERS >3, FRS >5 and FBS >10 patients needed endoscopic treatment. All scoring systems were able to predict rebleeding. In comparison of two groups for rebleeding, it was found that PEBS was better able to predict bleeding during follow-up than both FRS and FBS, and PERS was better able to predict bleeding during follow-up than both FRS and FBS. All scoring systems were able to predict mortality. FRS and PERS scores had a greater discriminatory power for predicting death than the rest of the scores (P < 0.001).

Conclusion

All scoring systems were effective for predicting need for blood transfusion, rebleeding, and death. GBS had more predictive power for transfusion need, PERS and PEBS for rebleeding, and FRS for mortality. PERS, FRS, and FBS were found to be effective in predicting endoscopic treatment.

Inflammatory cytokines IL-6 and TNF-α in patients with hip fracture

Mortality and remaining bedridden following the hip fracture surgery are not rare. We tried to measure the levels of inflammatory markers tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) following the hip fracture surgery and compare their levels with controls. We aimed to show a relationship between the levels of these markers and post-operative mortality and walking capability.

INTRODUCTION

Osteoporosis is a condition, causing the hip fractures in the elderly. Hip fractures have a high rate of overall mortality up to 30% following the incident. Cytokines such as IL-6 and TNF-α are suggested to play a role in bone resorption and, thus, in the etiology of osteoporosis.

METHODS

Plasma levels of IL-6 and TNF-α were measured pre-operatively and on the first and second days after the surgery in 40 Turkish hip fracture patients. The levels of these cytokines were compared with 40 Turkish age-matched healthy controls. The levels of these cytokines were compared between the deceased and surviving patients, as well as the existence of walking capability following the surgery.

RESULTS

Significantly higher IL-6 levels were shown on the first and second days after the surgery (p = 0.005; p = 0.01, respectively). The overall death rate of our study group within the 2-year follow-up time was found to be 35%. No statistical significance was found in the means of 2-year follow-up mortality between the patients. Presence of walking capability did not differ between the patients, as well.

CONCLUSION

We demonstrated an association between IL-6 levels and hip fracture in our study group following the surgery. We also suggest that TNF-α and IL-6 levels are not related to the occurrence of death and walking capability after the surgery. However, these findings need further functional and clinical confirmation.

The relationship between severity of ulcerative colitis and thiol-disulphide homeostasis

OBJECTIVES

The aim of the study was to determine dynamic thiol-disulphide homeostasis in patients with ulcerative colitis, compare it with those of healthy control and to investigate the relationship between the severity of the disease and homeostasisMETHODS: A total of 78 patients and 58 healthy subjects were included in the study. Serum native thiol, total thiol and disulphide amounts were measured by using a novel automated method. Obtained results were compared and relationships were determined by correlation analysis.

RESULTS

Serum native thiol, total thiol, disulphide amounts and disulphide/native thiol percent ratio (index) were significantly lower (p = 0.003 for index ratio and p < 0.001 for other parameters) in patients with ulcerative colitis than in healthy controls. Native thiol, total thiol and disulphide amounts were significantly higher (p < 0.001) in patients with ulcerative colitis in remission than in patients with active ulcerative colitis and near to those of healthy control. There were significant negative correlations between the severity of the disease and thiol-disulphide homeostasis parameters (r = -0.55, p < 0.001 for native thiol; r = -0.64, p < 0.0001 for total thiol; r = -0.65, p < 0.001 for disulphide and r = -0.33, p = 0.011 for index).

CONCLUSION

The thiol-disulphide homeostasis was weakened in ulcerative colitis. Strong correlations between the activity of the disease and thiol-disulfide homeostasis indicate that homeostasis may play a role in the pathogenesis of the disease (Tab. 3, Fig. 3, Ref. 30).

The efficacy of ozone therapy in neonatal rats with hypoxic ischemic brain injury

OBJECTIVES

This study is aimed to determine the effect of ozone therapy in neonatal rats with experimentally induced hypoxic ischemic brain injury (HIBI).

METHODS

The study included 7-d-old male Wistar rats that were randomized to the sham, control, ozone 1, and ozone 2 groups. All rats except those in the sham group were kept in a hypoxia chamber, and then the rats in the control group were given 0.5 mL of saline. Those in the ozone 1 group were given ozone 1 mg kg-1 intraperitoneally, and those in the ozone 2 group were given ozone 2 mg kg-1 intraperitoneally.

RESULTS

There were significantly fewer apoptotic neurons in the right hemispheres of the rats in the ozone 1 and ozone 2 groups than in the control group (p < 0.001 and p < 0.001, respectively). There were significantly fewer apoptotic neurons in the right hemispheres of the rats in the ozone 2 group than in the ozone 1 group (p < 0.001). Morris Water Maze (MWM) test results were similar in the ozone 2 and sham groups.

CONCLUSIONS

The present study's findings show that ozone therapy reduced neuronal apoptosis and improved cognitive function in neonatal rats with experimentally induced HIBI (Tab. 2, Ref. 30).

The effects of Desflurane and Sevoflurane on Nesfatin-1 levels in laparoscopic Cholecystectomy: a randomized controlled trial

Background

Nesfatin-1 is involved in cardiovascular regulation, stress-related responses. The objective of this study is to investigate the impact of volatile anesthetics on Nesfatin-1 levels.

Method

Fourty-two patients aged 30–65 years with the American Society Anesthesiology (ASA) Class I-II who were scheduled for laparoscopic cholecystectomy were included in the study Patients were randomized into two group; desflurane administered group (Group I, n = 21) and sevoflurane administered group (Group II, n = 21). For anesthesia maintenance, the patients received 6% desflurane or 2% sevoflurane in 40% O2 and 60% air. The patient’s heart rate (HR), mean, systolic and diastolic arterial pressures (MAP, SAP, DAP), peripheral O2 saturation (SpO2) were monitored and recorded before induction, after induction, after intubation, and during extubation. Blood samples were collected before induction (T1), and after extubation when aldrete score was 10 (T2).

Results

Demographic data were similar between the groups. The preoperative levels of nesfatin were similar in the two groups (p = 0.715). In desflurane group, post-operative nesfatin levels were similar compared to preoperative levels (p = 0.073). In sevoflurane group, post-operative nesfatin levels were similar (p = 0.131). The nesfatin levels (postoperative vs preoperative) were similar between the groups (p = 0.900).

Conclusion

In conclusion, this study results suggest that nesfatin-1 levels are not affected by the use of sevoflurane or desflurane in patients undergoing laparoscopic cholecystectomy.

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12617001023347, retrospectively registered on 17 July 2017.

Is levetiracetam neuroprotective in neonatal rats with hypoxic ischemic brain injury?

BACKGROUND

The aim of this study was to determine if levetiracetam (LEV) is neuroprotective in neonatal rats with hypoxic-ischemic brain injury (HIBI).

METHODS

The study included 7-d-old male Wistar rats that were randomly divided into the LEV400, LEV800, control, and sham groups. All the rats, except those in the sham group, underwent ligation of the carotid artery and were then kept in a hypoxic chamber containing 8% oxygen for 2 h. At the end of the hypoxic period the rats in the control group were administered saline solution 0.5 mL, the rats in the LEV400 group were administered LEV 400 mg.kg-1, and rats in the LEV800 group were administered LEV 800 mg.kg-1 via the intraperitoneal route. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) method was used to evaluate neuronal apoptosis in the rats. The Morris Water Maze (MWM) test was performed at age 14 weeks in order to evaluate cognitive function.

RESULTS

The number of apoptotic neurons in the right hemispheres was significantly lower in the sham, LEV400, and LEV800 groups than in the control group (p < 0.001, p < 0.001, and p < 0.001, respectively). In addition, the number of apoptotic neurons in the right hemispheres was significantly lower in the LEV800 group than in the LEV400 group (p = 0.001). Platform finding time (PFT) during MWM testing was significantly shorter in the sham and LEV800 groups on d 4 than on d 1 (p = 0.001 and p = 0.006, respectively); however, PFT did not significantly change between d 1 and d 4 in the control or LEV400 groups (p = 0.91 and p = 0.096, respectively).

CONCLUSION

Based on the present findings, LEV exhibited a dose-dependent neuroprotective effect in neonatal rats with HIBI (Ref. 27).

Nano drug delivery systems and gamma radiation sterilization

In recent years, drug delivery systems such as liposomes and microparticles have been used in clinic for the treatment of different diseases and from a regulatory point of view, a parenterally applied drug and drug delivery systems must be sterile and pyrogen free. Radiation sterilization is a method recognized by pharmacopoeias to achieve sterility criteria of parenterals. It has the ability to kill microorganisms in therapeutic products. The ability of, however, irradiation might also affect the performance of drug delivery systems. One of the most critical points is irradiation dose, because certain undesirable chemical and physical changes may accompany with the irradiation, especially with the traditionally applied dose of 25 kGy. Its ionizing property may cause fragmentation of covalent bond. The care must be paid to the applied dose. In this research, the effects of gamma irradiation on different drug delivery systems such as chitosan microparticles, liposomes, niosomes and sphingosomes were investigated. According to the experimental data, it can be concluded that gamma irradiation can be a suitable sterilization technique for liposome, niosome and sphingosome dispersions. When all irradiated drug carrier systems were taken into consideration, chitosan glutamate microparticles were found as the most radioresistant drug delivery system among the others.

Attitude of medical students towards occupational safety and health: a multi-national study

BACKGROUND

Work-related diseases contribute immensely to the global burden of diseases. Better understanding of attitudes of health care workers towards occupational safety and health (OSH) is important for planning.

OBJECTIVE

To assess the attitude of medical students towards OSH around the globe.

METHODS

A questionnaire assessing the attitude towards OSH was administered to medical and paramedical students of 21 Medical Universities across the globe. In the current study 1895 students, aged 18-36 years, from 17 countries were included. After having performed a principal components analysis, the associations of interest between the identified components and other socio demographic characteristics were assessed by multivariate linear regression.

RESULTS

Principal component analysis revealed 3 components. Students from lower and lower-middle-income countries had a more positive attitude towards OSH, but the importance of OSH was still rated higher by students from upper-income countries. Although students from Asian and African continents showed high interest for OSH, European and South-Central American students comparatively rated importance of OSH to be higher. Paramedical students had more positive attitude towards OSH than medical students.

CONCLUSION

The attitude of students from lower-income and lower-middle-income towards importance of OSH is negative. This attitude could be changed by recommending modifications to OSH courses that reflect the importance of OSH. Since paramedical students showed more interest in OSH than medical students, modifications in existing health care system with major role of paramedics in OSH service delivery is recommended.

Urologic health condition of spinal cord-injured patients living in Turkey

OBJECTIVES

To determine the urologic health condition of spinal cord-injured (SCI) patients living in Turkey, and to analyze the relationship between the prevalence of urologic health condition parameters and the patient's characteristics.

METHODS

Telephone call survey was conducted with a structured questionnaire among all members of Turkish Society of Spinal Cord Injured Patients.

RESULTS

Data were obtained from 300 patients. Mean age was 42 years with a male/female ratio of 2.3, while the most common cause of injury was transport (35.3%). Although 70% were aware of potential kidney and bladder problems after injury >60% of the patients were not under regular urologic follow-up. Secondary health problems experienced as being most important was urination problems (50%). Of the patients 72.7% (83% in females vs 68% in males) had urinary incontinence (UI) during last 3 months, and 64.3% used clean intermittent catheterization (CIC) (68% in males vs. 56% in females), while 73%, 57% and 26% of incontinent patients used diaper/pad, medication and condom catheter, respectively, and the use of CIC decreased with time. Surgical procedures on urinary tract were performed in 22.6% of the patients; stone surgeries were the most frequent ones.

CONCLUSION

This study demonstrated that the UI rate was high among SCI patients, and more common in females with fairly good proportion of patients using incontinence medication. Main bladder management method was CIC and more prevalent in males, although the use of CIC decreased with time. Urinary stone surgery was the leading surgical procedure.

ASCL1 and RET expression defines a clinically relevant subgroup of lung adenocarcinoma characterized by neuroendocrine differentiation

ASCL1 is an important regulatory transcription factor in pulmonary neuroendocrine (NE) cell development, but its value as a biomarker of NE differentiation in lung adenocarcinoma (AD) and as a potential prognostic biomarker remains unclear. We examined ASCL1 expression in lung cancer samples of varied histologic subtype, clinical outcome and smoking status and compared with expression of traditional NE markers. ASCL1 mRNA expression was found almost exclusively in smokers with AD, in contrast to non-smokers and other lung cancer subtypes. ASCL1 protein expression by immunohistochemical (IHC) analysis correlated best with synaptophysin compared with chromogranin and CD56/NCAM. Analysis of a compendium of 367 microarray-based gene expression profiles in stage I lung adenocarcinomas identified significantly higher expression levels of the RET oncogene in ASCL1-positive tumors (ASCL1(+)) compared with ASCL1(-) tumors (q-value <10(-9)). High levels of RET expression in ASCL1(+) but not in ASCL1(-) tumors was associated with significantly shorter overall survival (OS) in stage 1 (P=0.007) and in all AD (P=0.037). RET protein expression by IHC had an association with OS in the context of ASCL1 expression. In silico gene set analysis and in vitro experiments by ASCL1 shRNA in AD cells with high endogenous expression of ASCL1 and RET implicated ASCL1 as a potential upstream regulator of the RET oncogene. Also, silencing ASCL1 in AD cells markedly reduced cell growth and motility. These results suggest that ASCL1 and RET expression defines a clinically relevant subgroup of ∼10% of AD characterized by NE differentiation.

Can exposure to manganese and extremely low frequency magnetic fields affect some important elements in the rat teeth?

BACKGROUND

Length and level of exposure to electromagnetic fields (EMFs) is increasing in association with the widespread use of electrical and electronic devices and technological progress. The undesirable effects of extremely low frequency magnetic fields (ELF-MFs) on health have attracted considerable interest.

MATERIALS AND METHODS

Sixty-four four-month-old male Wistar rats divided into eight groups of eight rats each were used. Seven groups were exposed to varying dosages of manganese (Mn) and a 50 Hz magnetic field (MF) of approximately 1 mT, while the last group was set aside as the cage control group and not subjected to any procedure. This study was intended to investigate the interactions between the application of MF and Mn and the elements Ca, Zn, Mg, and P thought to be involved in caries, in rat teeth.

RESULTS

Levels of Ca, Mg, Zn, and P in the experimental group rats were different to those in the control group.

CONCLUSIONS

The results demonstrate that ELF-MF and Mn can have significant effects on levels of elements in rat teeth. Further experimental and epidemiological studies of ELF-MF and Mn are needed in order to evaluate their dental effects.

Shared gene expression alterations in prostate cancer and histologically benign prostate from patients with prostate cancer

Prostate cancer (PCa) field effect alterations provide important clues regarding the initiation of these tumors and suggest targets for prevention or biomarkers for early detection. However, biomarkers of PCa field effects that have passed independent validation are lacking, largely because these alterations are subtle and difficult to distinguish from unrelated small changes in gene expression. We hypothesized that shared expression alterations in PCa and benign prostates containing PCa (BPCs) would have a higher potential for independent validation than alterations identified in BPCs alone. Expression analyses were performed on 37 PCas and 36 unmatched BPCs and were contrasted with 28 benign prostates (BPs) from patients free of PCa. Most of the protein-coding genes and nonexonic RNAs selected according to the hypothesis were validated by quantitative RT-PCR in an independent set of 51 BPCs and BPs. A statistical model based on two markers distinguished BPCs from BPs in the RT-PCR set and in an external microarray (area under the curve = 0.84 and 0.90, respectively). In addition, genes with predominant expression in stroma were identified by expression profiling of pure stroma and epithelial cells. Pathway analysis identified dysregulated platelet-derived growth factor receptor signaling in BPC stroma. These results validate our approach for finding PCa field effect alterations and demonstrate a PCa transcriptome fingerprint in nonneoplastic cells in prostates containing cancer.

Abstract 3008: Shared gene expression alterations in prostate cancer and histologically benign prostate from patients with prostate cancer

The frequent observations of heterogeneous tumor foci in prostate cancers indicate that the molecular changes induced by carcinogenic insult take place over wide areas within the diseased prostate. These ‘field effect’ alterations provide important clues regarding the initiation of prostate cancer (PCa) and suggest targets for cancer prevention or biomarkers for early detection. However, PCa field effect biomarkers that have passed independent validation are lacking largely because these alterations are subtle and difficult to distinguish from unrelated small changes in gene expression in the benign prostate. We postulated that shared expression alterations in PCa and in benign prostate tissue in prostate glands that contain prostate cancer (BPC) would have a higher potential for independent validation than alterations identified in BPC alone. Expression analyses was performed on PCa (n = 37) and unmatched BPC (n = 36) and contrasted with benign prostate glands (BP) from patients free of prostate cancer (n =28). These analyses identified gene alterations that were concomitantly present in both PCa and BPC. The majority of the selected markers were validated by quantitative RT-PCR in an independent set of BPC (n = 33) and BP (n =18). Validated markers included genes and non-exonic sequences not previously associated with PCa field effect. A statistical model based on CCNB1 and non-exonic NACA locus discriminated between BPC and BP in the RT-PCR set and in an external microarray dataset with accuracies of 0.84 and 0.90, respectively. Genes with predominant expression in prostate stroma were identified by expression profiling of stroma and epithelial cells collected by laser captured microdissection. Pathway analysis identified enriched GO categories in BPC stroma including PDGFR signaling. These results validate our approach for finding PCa field effect alterations and demonstrate a prostate cancer transcriptome fingerprint in the adjacent non-neoplastic cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3008. doi:1538-7445.AM2012-3008