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At least 181 records · Page 10

Identification of candidate diagnostic and prognostic biomarkers for human prostate cancer: RPL22L1 and RPS21

Prostate cancer (PCa) is one of the most common malignancies in men worldwide. This study was designed to investigate the potential of Ribosomal Protein L22-like1 (RPL22L1) and Ribosomal Protein S21 (RPS21) as diagnostic and prognostic biomarkers for PCa. First, RPL22L1 and RPS21 were screened as the key molecular of PCa by bioinformatics analysis. Subsequently, the prostate tissue samples were stained for antibodies against RPL22L1 and RPS21. The unbiased signal quantification was performed by ImageJ software, and the results showed that the expression of RPL22L1 and RPS21 exhibited significant differences between the PCa tissues and the normal prostate tissues. Receiver-operating characteristics (ROC) curves were prepared, and then the area under the curve (AUC) values of RPL22L1 and RPS21 were calculated as 0.798 and 0.768, and the likelihood ratio (LR) values of RPL22L1 and RPS21 were calculated as 2.86 and 2.53. These data implied that the over-expression of RPL22L1 and RPS21 is associated with the presence of PCa. The further analysis suggested that the expression of RPL22L1 and RPS21 were significantly higher in high Gleason grade than they were in low Gleason grade. In addition, in vitro studies were undertaken to evaluate the roles of RPL22L1 and RPS21 in PCa. The results revealed that these genes promote PCa cell proliferation, migration and invasion, and inhibit PCa cell apoptosis. Taken together, these data showed that RPL22L1 and RPS21 exhibited higher expression in human prostate cancer tissue, and involved in PCa cell proliferation and invasion. This research provided a novel insight into diagnostic and prognostic biomarkers for PCa.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Adenosine stress myocardial perfusion imaging in octogenarians: Safety, tolerability, and long-term prognostic implications of hemodynamic response and SPECT-related variables

Background: Evaluation of tolerability, safety, and prognostic implications of adenosine stress myocardial perfusion imaging (MPI) in octogenarians. Methods: 370 octogenarians (49% known coronary artery disease) were studied. Hemodynamic response, MPI-related data, and rest-left ventricular ejection fraction (LVEF) based on echocardiography were registered per patient, and prospective follow-up was performed to document all-cause death (ACD), cardiac death (CD), myocardial infarction (MI), and late revascularization. Results: No deaths or MIs were observed during adenosine infusion or the short-term post-infusion period. 86% of patients were able to tolerate a 6-minute infusion. All side effects terminated spontaneously after infusion cessation, except for one case of pulmonary oedema. After 9.3 years, there were 124 ACDs, 62 CDs, 16 MIs, and 35 revascularizations. Differences between survival curves of summed stress score (SSS)-based risk groups were significant for all end points (P < .001). SSS and LVEF were independent predictors of all end points (P ≤ .01) and lung uptake of cardiac end points. ΔHR <10 bpm (OR = 1.78, P = .004) and inability to increase HR by >10 bpm and decrease systolic blood pressure by >10 mmHg (OR = 2, P = .02) during adenosine infusion were independent predictors of ACD and CD, respectively. Hemodynamic response variables, SSS, and lung uptake provided incremental prognostic value over pre-test data for ACD and CD. Conclusions: In octogenarians, adenosine stress MPI is well tolerated and provides effective long-term risk stratification.

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Added prognostic value of left ventricular shape by gated SPECT imaging in patients with suspected coronary artery disease and normal myocardial perfusion

Background: Left ventricular (LV) remodeling is associated with adverse cardiovascular events. We evaluated the added prognostic value of LV shape index (SI) assessed by gated single-photon emission tomography (SPECT) in patients without known coronary artery disease (CAD). Methods and results: We studied 674 patients with normal myocardial perfusion and normal LV ejection fraction (EF) on stress gated SPECT imaging. An automated software program was used to calculate end-diastolic and end-systolic LVSI. An LVSI ≤ 0.54 at end-systole was considered normal. Follow-up was 96% complete with a median follow-up of 37 months. During follow-up, 25 events occurred (3.8% cumulative event rate). Event-free survival was lower in patients with abnormal end-systolic LVSI (P < .001). Age (P = .021), diabetes (P = .048), and end-systolic LVSI (P < .001) were independent predictors of events. LVSI added prognostic information increasing the global chi-square of the model including age and diabetes from 15.15 to 25.97 (P < .001). The effect of diabetes on hazard ratio increased with increasing values of end-systolic LVSI. The probability of events at 48 months predicted by Weibull analysis progressively increased with increasing values of end-systolic LVSI and was higher in patients with diabetes as compared to those without. Decision curve analyses indicate that the model including end-systolic LVSI resulted in an increased net benefit between 5% and 30% threshold probability, indicating superior estimation of outcomes at low threshold probability levels. Conclusions: The evaluation of LVSI may identify patients with early-stage LV remodeling and at higher risk of adverse cardiac events, even in the presence of normal myocardial perfusion.

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PDGF family function and prognostic value in tumor biology

Highlights: • Large scale transcriptomic data analysis reveals tumor-specific roles of PDGF signaling. • Functional gene sets associated with PDGF expression are conserved between PDGF family members. • PDGF related gene signatures have increased prognostic value over each single gene. The development and progression of a tumor depends on the close interaction of malignant cells and the supportive and suppressive tumor microenvironment. Paracrine signaling enables tumor cells to shape the surrounding tissue in order to decrease recognition by the immune system, attract blood vessels to fuel growth, change metabolic programs, and induce wound healing programs. In this study, we investigate the role of the platelet-derived growth factor (PDGF) family members PDGFA, PDGFB, PDGFC and PDGFD and their cognate tyrosine kinase receptors PDGFRA and PDGFRB, using publicly available data from The Cancer Genome Atlas and the Human Protein Atlas. Large scale analysis of expression correlation in RNA sequencing data from 7616 samples derived from 16 tumor types, revealed conserved functional programs in PDGF signaling in the majority of solid tumor types. Besides the well-known effects of PDGF signaling in mesenchymal cells, our analyses revealed a potential role of PDGF signaling in the composition of the immune microenvironment. We furthermore derived gene signatures with increased prognostic value for each PDGF family member. This study emphasizes the potential to impinge on specific paracrine signaling events to interfere with the crosstalk between malignant cells and their microenvironment.

60 APPLIED LIFE SCIENCES↗

Prognostic significance of interferon regulating factor 4 in esophageal squamous cell carcinoma

Highlights: • Increased expression of IRF4 is closely related to improved ESCC outcome. • IRF4 serve as an independent predictor of a positive prognosis in ESCC patients. • IRF4 may represent a promising prognostic biomarker and potential immuno-therapeutic target for ESCC patients. Aberrant expression of interferon regulatory factor 4 (IRF4) has been reported in several hematologic malignancies. However, the prognostic significance of IRF4 expression in esophageal squamous cell carcinoma (ESCC) remains unknown.

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Prognostic Factors and Outcome in Askin-Rosai Tumor: A Review of 104 Patients

Purpose: To evaluate the prognostic factors and treatment outcome of patients with Askin-Rosai tumor of the chest wall treated at a single institution. Methods and Materials: Treatment comprised multiagent chemotherapy and local therapy, which was either in the form of surgery alone, radical external-beam radiotherapy (EBRT) alone, or a combination of surgery and EBRT. Thirty-two patients (40%) were treated with all three modalities, 21 (27%) received chemotherapy and radical EBRT, and 19 (24%) underwent chemotherapy followed by surgery only. Results: One hundred four consecutive patients aged 3-60 years were treated at the Tata Memorial Hospital from January 1995 to October 2003. Most (70%) were male (male/female ratio, 2.3:1). Asymptomatic swelling (43%) was the most common presenting symptom, and 25% of patients presented with distant metastasis. After a median follow-up of 28 months, local control, disease-free survival, and overall survival rates were 67%, 36%, and 45%, respectively. Median time to relapse was 25 months, and the median survival was 76 months. Multivariate analysis revealed age {>=}18 years, poor response to induction chemotherapy, and presence of pleural effusion as indicators of inferior survival. Fifty-six percent of patients with metastatic disease at presentation died within 1 month of diagnosis, with 6-month and 5-year actuarial survival of 14% and 4%, respectively. Conclusion: Primary tumor size, pleural effusion, response to chemotherapy, and optimal radiotherapy were important prognostic factors influencing outcome. The combination of neoadjuvant chemotherapy, surgery, and radiotherapy resulted in optimal outcome.

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A Comparison of the Prognostic Value of Early PSA Test-Based Variables Following External Beam Radiotherapy, With or Without Preceding Androgen Deprivation: Analysis of Data From the TROG 96.01 Randomized Trial

Purpose: We sought to compare the prognostic value of early prostate-specific antigen (PSA) test-based variables for the 802 eligible patients treated in the Trans-Tasman Radiation Oncology Group 96.01 randomized trial. Methods and Materials: Patients in this trial had T2b, T2c, T3, and T4 N0 prostate cancer and were randomized to 0, 3, or 6 months of neoadjuvant androgen deprivation therapy (NADT) prior to and during radiation treatment at 66 Gy to the prostate and seminal vesicles. The early PSA test-based variables evaluated were the pretreatment initial PSA (iPSA) value, PSA values at 2 and 4 months into NADT, the PSA nadir (nPSA) value after radiation in all patients, and PSA response signatures in men receiving radiation. Comparisons of endpoints were made using Cox models of local progression-free survival, distant failure-free survival, biochemical failure-free survival, and prostate cancer-specific survival. Results: The nPSA value was a powerful predictor of all endpoints regardless of whether NADT was given before radiation. PSA response signatures also predicted all endpoints in men treated by radiation alone. iPSA and PSA results at 2 and 4 months into NADT predicted biochemical failure-free survival but not any of the clinical endpoints. nPSA values correlated with those of iPSA, Gleason grade, and T stage and were significantly higher in men receiving radiation alone than in those receiving NADT. Conclusions: The postradiation nPSA value is the strongest prognostic indicator of all early PSA-based variables. However, its use as a surrogate endpoint needs to take into account its dependence on pretreatment variables and treatment method.

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Clinical Usefulness of [(18)F]Fluoro-2-Deoxy-D-Glucose Uptake in 178 Head-and-Neck Cancer Patients With Nodal Metastasis Treated With Definitive Chemoradiotherapy: Consideration of Its Prognostic Value and Ability to Provide Guidance for Optimal Selection of Patients for Planned Neck Dissection

Purpose: To evaluate the clinical effectiveness of pretreatment [(18)F]fluoro-2-deoxy-D-glucose-positron emission tomography for head-and-neck squamous cell carcinoma patients with nodal metastasis treated with chemoradiotherapy. Methods and Materials: Between March 2002 and December 2006, 178 patients with head-and-neck squamous cell carcinoma and nodal metastasis underwent fluoro-2-deoxy-D-glucose positron emission tomography before chemoradiotherapy. Fluoro-2-deoxy-D-glucose uptake by both the primary lesion and the neck node was measured using the standard uptake value (SUV). The overall survival, disease-free survival, local control, nodal progression-free survival, and distant metastasis-free survival rates were calculated, and several prognostic factors were evaluated. Results: The patients with a nodal SUV {>=}6.00 had a significantly lower 3-year disease-free survival rate than those with a lower SUV (44% vs. 69%, p = .004). On multivariate analysis, a high SUV of nodal disease also proved to be a significantly unfavorable factor for disease-free survival (p = .04, 95% confidence interval [CI], 1.02-3.23), nodal progression-free survival (p = .05; 95% CI, 1.00-4.15), and distant metastasis-free survival (p = .016; 95% CI, 1.25-8.92). Among the patients with a greater nodal SUV ({>=}6.00), those treated with planned neck dissection had better nodal progression-free survival than those in the observation group (p = .04, hazard ratio, 2.36; 95% CI, 1.00-5.85). Conclusion: Among head-and-neck squamous cell carcinoma patients treated with chemoradiotherapy, the pretreatment SUV of nodal disease was one of the strongest prognostic factors and also provided important information for the selection of patients suitable for planned neck dissection.

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High-Grade Acute Organ Toxicity as a Positive Prognostic Factor in Primary Radiochemotherapy for Anal Carcinoma

Purpose: To test for a possible correlation between high-grade acute organ toxicity during primary radiochemotherapy and treatment outcome for patients with anal carcinoma. Methods and Materials: From 1991 to 2009, 72 patients with anal carcinoma were treated at our department (10 patients had stage I, 28 patients had stage II, 11 patients had stage IIIA, and 13 patients had stage IIIB cancer [Union Internationale Contre le Cancer criteria]). All patients received normofractionated (1.8 Gy/day, five times/week) whole-pelvis irradiation including iliac and inguinal lymph nodes with a cumulative dose of 50.4 Gy. Concomitant chemotherapy regimen consisted of two cycles of 5-fluorouracil (1,000 mg/m{sup 2}total body surface area (TBSA)/day as continuous intravenous infusion on days 1-4 and 29-32) and mitomycin C (10 mg/m{sup 2}/TBSA, intravenously on days 1 and 29). Toxicity during treatment was monitored weekly, and any incidence of Common Toxicity Criteria (CTC) grade of {>=}3 for skin reaction, cystitis, proctitis, or enteritis was assessed as high-grade acute organ toxicity for later analysis. Results: We found significant correlation between high-grade acute organ toxicity and overall survival, locoregional control, and stoma-free survival, which was independent in multivariate analysis from other possible prognostic factors: patients with a CTC acute organ toxicity grade of {>=}3 had a 5-year overall survival rate of 97% compared to 30% in patients without (p < 0.01, multivariate analysis; 97% vs. 48%, p = 0.03 for locoregional control, and 95% vs. 59%, p = 0.05 for stoma-free survival). Conclusions: Our data indicate that normal tissue and tumor tissue may behave similarly with respect to treatment response, since high-grade acute organ toxicity during radiochemotherapy showed itself to be an independent prognostic marker in our patient population. This hypothesis should be further analyzed by using biomolecular and clinical levels in future clinical trials.

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Nuclear Factor {kappa}-Light Chain-Enhancer of Activated B Cells is Activated by Radiotherapy and is Prognostic for Overall Survival in Patients With Rectal Cancer Treated With Preoperative Fluorouracil-Based Chemoradiotheraphy

Purpose: Rectal cancer is often clinically resistant to radiotherapy (RT) and identifying molecular markers to define the biologic basis for this phenomenon would be valuable. The nuclear factor {kappa}-light chain-enhancer of activated B cells (NF-{kappa}B) is a potential anti-apoptotic transcription factor that has been associated with resistance to RT in model systems. The present study was designed to evaluate NF-{kappa}B activation in patients with rectal cancer undergoing chemoradiotherapy to determine whether NF-{kappa}B activity correlates with the outcome in rectal cancer patients. Methods and Materials: A total of 22 patients underwent biopsy at multiple points in a prospective study and the data from another 50 were analyzed retrospectively. The pretreatment tumor tissue was analyzed for multiple NF-{kappa}B subunits by immunohistochemistry. Serial tumor biopsy cores were analyzed for NF-{kappa}B-regulated gene expression using reverse transcriptase polymerase chain reaction and for NF-{kappa}B subunit nuclear localization using immunohistochemistry. Results: Several NF-{kappa}B target genes (Bcl-2, cellular inhibitor of apoptosis protein [cIAP]2, interleukin-8, and tumor necrosis factor receptor-associated-1) were significantly upregulated by a single fraction of RT at 24 h, demonstrating for the first time that NF-{kappa}B is activated by RT in human rectal tumors. The baseline NF-{kappa}B p50 nuclear expression did not correlate with the pathologic response to RT. However, an increasing baseline p50 level was prognostic for overall survival (hazard ratio, 2.15; p = .040). Conclusion: NF-{kappa}B nuclear expression at baseline in rectal cancer was prognostic for overall survival but not predictive of the response to RT. Larger patient numbers are needed to assess the effect of NF-{kappa}B target gene upregulation on the response to RT. Our results suggest that NF-{kappa}B might play an important role in tumor metastasis but not to the resistance to chemoradiotherapy.

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Development and Validation of a Prognostic Model Using Blood Biomarker Information for Prediction of Survival of Non-Small-Cell Lung Cancer Patients Treated With Combined Chemotherapy and Radiation or Radiotherapy Alone (NCT00181519, NCT00573040, and NCT00572325)

Purpose: Currently, prediction of survival for non-small-cell lung cancer patients treated with (chemo)radiotherapy is mainly based on clinical factors. The hypothesis of this prospective study was that blood biomarkers related to hypoxia, inflammation, and tumor load would have an added prognostic value for predicting survival. Methods and Materials: Clinical data and blood samples were collected prospectively (NCT00181519, NCT00573040, and NCT00572325) from 106 inoperable non-small-cell lung cancer patients (Stages I-IIIB), treated with curative intent with radiotherapy alone or combined with chemotherapy. Blood biomarkers, including lactate dehydrogenase, C-reactive protein, osteopontin, carbonic anhydrase IX, interleukin (IL) 6, IL-8, carcinoembryonic antigen (CEA), and cytokeratin fragment 21-1, were measured. A multivariate model, built on a large patient population (N = 322) and externally validated, was used as a baseline model. An extended model was created by selecting additional biomarkers. The model's performance was expressed as the area under the curve (AUC) of the receiver operating characteristic and assessed by use of leave-one-out cross validation as well as a validation cohort (n = 52). Results: The baseline model consisted of gender, World Health Organization performance status, forced expiratory volume, number of positive lymph node stations, and gross tumor volume and yielded an AUC of 0.72. The extended model included two additional blood biomarkers (CEA and IL-6) and resulted in a leave-one-out AUC of 0.81. The performance of the extended model was significantly better than the clinical model (p = 0.004). The AUC on the validation cohort was 0.66 and 0.76, respectively. Conclusions: The performance of the prognostic model for survival improved markedly by adding two blood biomarkers: CEA and IL-6.

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Prognostic Value of Pretreatment Carcinoembryonic Antigen After Definitive Radiotherapy With or Without Concurrent Chemotherapy for Squamous Cell Carcinoma of the Uterine Cervix

Purpose: To evaluate whether pretreatment carcinoembryonic antigen (CEA) levels have a prognostic role in patients after definitive radiotherapy for squamous cell carcinoma (SCC) of the uterine cervix. Methods and Materials: A retrospective study of 550 patients was performed. The SCC antigen (SCC-Ag) and CEA levels were regarded as elevated when they were {>=}2 and {>=}5 ng/mL, respectively. A total of 208 patients underwent concurrent chemoradiotherapy (CCRT). The Kaplan-Meier method was used to calculate the distant metastasis (DM), local failure (LF), disease-free survival (DFS), and overall survival (OS) rates. Multivariate analysis was performed using the Cox proportional hazards model. The hazard ratio (HR) with 95% confidence interval (CI) was evaluated for the risk of a poor prognosis. Results: Compared with the patients with normal CEA/SCC-Ag levels, CEA levels {>=}10 ng/mL but without elevated SCC-Ag levels was an independent factor for LF (HR, 51.81; 95% CI, 11.51-233.23; p < .001), DM (HR, 6.04; 95% CI, 1.58-23.01; p = .008), DFS (HR, 10.17; 95% CI, 3.18-32.56; p < .001), and OS (HR, 5.75; 95% CI, 1.82-18.18; p = .003) after RT alone. However, no significant role for CEA was noted in patients with SCC-Ag levels {>=}2 ng/mL. In patients undergoing CCRT, a CEA level {>=}10 ng/mL was an independent factor for LF (HR, 2.50; 95% CI, 1.01-6.21; p = .047), DM (HR, 3.41; 95% CI, 1.56-7.46; p = .002), DFS (HR, 2.73; 95% CI, 1.39-5.36; p = .003), and OS (HR, 3.93; 95% CI 1.99-7.75; p < .001). A SCC-Ag level of {>=}40 ng/mL was another prognostic factor for DM, DFS, and OS in patients undergoing not only CCRT, but also RT alone. The 5-year OS rate for CCRT patients with CEA <10 ng/mL and {>=}10 ng/mL was 75.3% and 35.8%, respectively (p < .001). CCRT was an independent factor for better OS (HR, 0.69; 95% CI, 0.50-0.97; p = .034). Conclusion: Pretreatment CEA levels in patients with SCC of the uterine cervix provide complementary information for predicting LF, DM, DFS, and OS, except for in patients with abnormal SCC-Ag levels before RT alone. More aggressive therapy might be advisable for patients with CEA levels of {>=}10 ng/mL.

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Stage I-IIA Non-Bulky Hodgkin's Lymphoma. Is Further Distinction Based on Prognostic Factors Useful? The Stanford Experience

Purpose: In the United States, early-stage Hodgkin's lymphoma (HL) is defined as asymptomatic stage I/II non-bulky disease. European groups stratify patients to more intense treatment by considering additional unfavorable factors, such as age, number of nodal sites, sedimentation rate, extranodal disease, and elements of the international prognostic score for advanced HL. We sought to determine the prognostic significance of these factors in patients with early-stage disease treated at Stanford University Medical Center. Methods and Materials: This study was a retrospective analysis of 101 patients treated with abbreviated Stanford V chemotherapy (8 weeks) and 30-Gy (n = 84 patients) or 20-Gy (n = 17 patients) radiotherapy to involved sites. Outcomes were assessed after applying European risk factors. Results: At a median follow-up of 8.5 years, freedom from progression (FFP) and overall survival (OS) rates were 94% and 97%, respectively. From 33% to 60% of our patients were unfavorable per European criteria (i.e., German Hodgkin Study Group [GHSG], n = 55%; European Organization for Research and Treatment of Cancer, n = 33%; and Groupe d'Etudes des Lymphomes de l'Adulte, n = 61%). Differences in FFP rates between favorable and unfavorable patients were significant only for GHSG criteria (p = 0.02) with there were no differences in OS rates for any criteria. Five of 6 patients who relapsed were successfully salvaged. Conclusions: The majority of our patients deemed unfavorable had an excellent outcome despite undergoing a significantly abbreviated regimen. Application of factors used by the GHSG defined a less favorable subset for FFP but with no impact on OS. As therapy for early-stage disease moves to further reductions in therapy, these factors take on added importance in the interpretation of current trial results and design of future studies.

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Prognostic Cell Biological Markers in Cervical Cancer Patients Primarily Treated With (Chemo)radiation: A Systematic Review

The aim of this study was to systematically review the prognostic and predictive significance of cell biological markers in cervical cancer patients primarily treated with (chemo)radiation. A PubMed, Embase, and Cochrane literature search was performed. Studies describing a relation between a cell biological marker and survival in {>=}50 cervical cancer patients primarily treated with (chemo)radiation were selected. Study quality was assessed, and studies with a quality score of 4 or lower were excluded. Cell biological markers were clustered on biological function, and the prognostic and predictive significance of these markers was described. In total, 42 studies concerning 82 cell biological markers were included in this systematic review. In addition to cyclooxygenase-2 (COX-2) and serum squamous cell carcinoma antigen (SCC-ag) levels, markers associated with poor prognosis were involved in epidermal growth factor receptor (EGFR) signaling (EGFR and C-erbB-2) and in angiogenesis and hypoxia (carbonic anhydrase 9 and hypoxia-inducible factor-1{alpha}). Epidermal growth factor receptor and C-erbB-2 were also associated with poor response to (chemo)radiation. In conclusion, EGFR signaling is associated with poor prognosis and response to therapy in cervical cancer patients primarily treated with (chemo)radiation, whereas markers involved in angiogenesis and hypoxia, COX-2, and serum SCC-ag levels are associated with a poor prognosis. Therefore, targeting these pathways in combination with chemoradiation may improve survival in advanced-stage cervical cancer patients.

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Enhancer of Zeste Homolog 2 Overexpression in Nasopharyngeal Carcinoma: An Independent Poor Prognosticator That Enhances Cell Growth

Purpose: As a key component of polycomb-repressive complex 2, enhancer of zeste homolog 2 (EZH2) represses target genes through histone methylation and is frequently overexpressed and associated with poor prognosis in common carcinomas. For the first time, we reported EZH2 expression and its biological and clinical significance in nasopharyngeal carcinoma (NPC). Methods and Materials: In NPC cell lines and specimens, endogenous expression of EZH2 mRNA and protein was determined by semiquantitative reverse transcription-polymerase chain reaction and immunoblotting, respectively. To analyze the effect on cell growth, stable silencing of EZH2 was established in EZH2-expressing TW02 NPC cells with RNA interference. EZH2 immunolabeling was assessable for 89 primary NPC biopsy samples and correlated with clinicopathological variables, disease-specific survival (DSS), and overall survival (OS). Results: Growth activity of TW02 cells was significantly suppressed (p < 0.001) with stable EZH2 silencing. Compared with normal nasopharyngeal tissue, expression levels of EZH2 transcript and protein were apparently upregulated in NPC specimens. As a continuous variable, higher EZH2 expression preferentially occurred in NPCs of T3 to T4 stages (p = 0.03) and significantly predicted inferior DSS (p = 0.0010) and OS (p = 0.004). The prognostic implications for DSS (p = 0.010) and OS (p = 0.006) still remained valid when using the median ({>=}60%) of EZH2 immunolabeling index to dichotomize the cohort. In the multivariate model, higher EZH2 expression was an independent adverse factor of both DSS (p = 0.012) and OS (p = 0.011), along with American Joint Committee on Cancer Stages III to IV (p = 0.024 for DSS, p = 0.017 for OS). Conclusion: At least partly through promoting cell growth, EZH2 implicates disease progression, confers tumor aggressiveness, and represents an independent adverse prognosticator in patients with NPC.

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Exploratory Study of the Prognostic Value of Microenvironmental Parameters During Fractionated Irradiation in Human Squamous Cell Carcinoma Xenografts

Purpose: To explore the prognostic value of microenvironmental parameters for local tumor control determined before and during fractionated irradiation. Methods and Materials: Six human squamous cell carcinoma (hSCC) lines were transplanted subcutaneously into the right hind leg of nude mice. Tumors were irradiated with 30 fractions within 6 weeks. Local tumor control was determined 120 days after irradiation. Radiation response was quantified as dose to cure 50% of tumors (TCD{sub 50}). In parallel, untreated and irradiated tumors were excised after injection of pimonidazole (hypoxia marker) and Hoechst 33342 (perfusion marker) for histological evaluation. Results: Pimonidazole hypoxia decreased during fractionated irradiation in the majority of tumor lines. Fraction of perfused vessels and vascular area showed modest changes during fractionated irradiation. Histological parameters before treatment and after three and five fractions did not significantly correlate with TCD{sub 50} after irradiation with 30 fractions within 6 weeks (p > 0.05). Hypoxic volume and perfused vessels after 10 fractions showed a significant association with local tumor control after fractionated irradiation (p = 0.018 and p = 0.019, respectively). None of these parameters remained statistically significant when the p value was adjusted for multiple comparisons. Conclusions: The results from this exploratory study suggest that determination of microenvironmental parameters during treatment provides better prognostic information for the outcome after fractionated radiotherapy than pretreatment parameters, which warrants further investigation and confirmation in experimental and clinical studies.

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Outcome and Prognostic Factors in Endometrial Stromal Tumors: A Rare Cancer Network Study

Purpose: To provide further understanding regarding outcome and prognostic factors of endometrial stromal tumors (EST). Methods and Materials: A retrospective analysis was performed on the records of 59 women diagnosed with EST and treated with curative intent between 1983 and 2007 in the framework of the Rare Cancer Network. Results: Endometrial stromal sarcomas (ESS) were found in 44% and undifferentiated ESS (UES) in 49% of the cases. In 7% the grading was unclear. Of the total number of patients, 33 had Stage I, 4 Stage II, 20 Stage III, and 1 presented with Stage IVB disease. Adjuvant chemotherapy was administered to 12 patients, all with UES. External-beam radiotherapy (RT) was administered postoperatively to 48 women. The median follow-up was 41.4 months. The 5-year overall survival (OS) rate was 96.2% and 64.8% for ESS and UES, respectively, with a corresponding 5-year disease-free survival (DFS) rate of 49.4% and 43.4%, respectively. On multivariate analysis, adjuvant RT was an independent prognostic factor for OS (p = 0.007) and DFS (p = 0.013). Locoregional control, DFS, and OS were significantly associated with age ({<=}60 vs. >60 years), grade (ESS vs. UES), and International Federation of Gynecology and Obstetrics stage (I-II vs. III-IV). Positive lymph node staging had an impact on OS (p < 0.001). Conclusion: The prognosis of ESS differed from that of UES. Endometrial stromal sarcomas had an excellent 5-year OS, whereas the OS in UES was rather low. However, half of ESS patients had a relapse. For this reason, adjuvant treatment such as RT should be considered even in low-grade tumors. Multicenter randomized studies are still warranted to establish clear guidelines.

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Prognostic Importance of Small Prostate Size in Men Receiving Definitive Prostate Brachytherapy

Purpose: To assess whether small prostate size is an adverse prognostic factor in men undergoing brachytherapy in the same manner in which it seems to be for men undergoing radical prostatectomy. Methods and Materials: From April 1995 to June 2008, 2024 patients underwent brachytherapy by a single brachytherapist. Median follow-up was 7.4 years. The role of small prostate size ({<=}20 cm{sup 3}) as a prognostic factor for biochemical progression-free survival, cause-specific survival, and all-cause mortality was investigated. The differences in survival between men with small and larger prostates were compared using Kaplan-Meier curves and log-rank tests. Results: Median prostate size for the entire cohort was 32.7 cm{sup 3}. For the 167 men with small prostates, median prostate size was 17.4 cm{sup 3}. There was no difference in biochemical progression-free survival (95.2% vs 96.2%, P=.603), cause-specific survival (97.7% vs 98.3%, P=.546), or all-cause mortality (78.0% vs 77.2%, P=.838) at 10 years for men with small prostates compared with men with larger prostates. On univariate and multivariate analysis, small prostate size was not associated with any of the primary outcome measures. Conclusion: Men with small prostates treated with brachytherapy have excellent outcomes and are at no higher risk of treatment failure than men with larger glands. High-quality implants with adequate margins seem sufficient to address the increased adverse risk factors associated with small prostate size.

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