Wael Sakr - Academia.edu (original) (raw)

Papers by Wael Sakr

Journal of clinical oncology : official journal of the American Society of Clinical Oncology, Jan 6, 2018

Purpose Patients with high-risk prostate cancer after radical prostatectomy are at risk for death... more Purpose Patients with high-risk prostate cancer after radical prostatectomy are at risk for death. Adjuvant androgen-deprivation therapy (ADT) may reduce this risk. We hypothesized that the addition of mitoxantrone and prednisone (MP) to adjuvant ADT could reduce mortality compared with adjuvant ADT alone. Methods Eligible patients had cT1-3N0 prostate cancer with one or more high-risk factors after radical prostatectomy (Gleason score [GS] ≥ 8; pT3b, pT4, or pN+ disease; GS 7 and positive margins; or preoperative prostate-specific antigen [PSA] > 15 ng/mL, biopsy GS score > 7, or PSA > 10 ng/mL plus biopsy GS > 6. Patients with PSA ≤ 0.2 ng/mL after radical prostatectomy were stratified by pT/N stage, GS, and adjuvant radiation plan and randomly assigned to ADT (bicalutamide and goserelin for 2 years) or ADT plus six cycles of MP. The primary end point was overall survival (OS). Median OS was projected to be 10 years in the ADT arm, requiring 680 patients per arm to det...

$Research paper thumbnail of Ixabepilone (Epothilone B Analogue BMS-247550) Is Active in Chemotherapy-Naive Patients With Hormone-Refractory Prostate Cancer: A Southwest Oncology Group Trial S0111$

Journal of Clinical Oncology, 2005

Purpose The epothilones are a new class of tubulin-polymerizing agents with activity in taxane-se... more Purpose The epothilones are a new class of tubulin-polymerizing agents with activity in taxane-sensitive and resistant tumor models. We evaluated ixabepilone (BMS-247550) in patients with metastatic hormone-refractory prostate cancer (HRPC). Methods Eligible patients had chemotherapy-naive metastatic HRPC, a Zubrod performance status of 0 to 2, and adequate organ function. All patients received BMS-247550 at 40 mg/m2 over 3 hours every 3 weeks. The primary end point was proportion of patients achieving a prostate-specific antigen (PSA) response. Results Forty-eight patients with metastatic HRPC were registered. Forty-two patients were eligible, with a median age of 73 years and a median PSA level of 111 ng/mL; 78% had bone-only or bone and soft tissue metastases, and 88% had objective radiologic disease progression at registration. Grade 3 and 4 adverse events (AEs) occurred in 16 and three patients, respectively. All grade 4 toxicities were neutropenia or leukopenia. The most frequ...

Journal of Clinical Oncology, 2011

Purpose Men with high-risk features (extraprostatic extension or high Gleason grade) face a high ... more Purpose Men with high-risk features (extraprostatic extension or high Gleason grade) face a high risk of prostate cancer recurrence after radical prostatectomy. Clinical trials of adjuvant systemic therapy for such patients have been limited. Patients and Methods The SWOG (Southwest Oncology Group) S9921 study randomly assigned 983 men with high-risk features at prostatectomy to receive adjuvant therapy with androgen deprivation (ADT) alone or in combination with mitoxantrone chemotherapy. ADT consisted of goserelin and bicalutamide for 2 years. Results Although the final primary treatment comparison results are not ready for publication, this article reports results in the ADT-alone control arm with a median follow-up of 4.4 years. For these 481 men, the estimated 5-year biochemical failure-free survival is 92.5% (95% CI, 90 to 95), and 5-year overall survival is 95.9% (95% CI, 93.9 to 97.9). Conclusion The results of this trial, taken in context, make a compelling argument for cou...

Oncotarget, Jan 30, 2014

The goal of the current study is to examine the biological effects of epithelial-specific tumor s... more The goal of the current study is to examine the biological effects of epithelial-specific tumor suppressor maspin on tumor host immune response. Accumulated evidence demonstrates an anti-tumor effect of maspin on tumor growth, invasion and metastasis. The molecular mechanism underlying these biological functions of maspin is thought to be through histone deacetylase inhibition, key to the maintenance of differentiated epithelial phenotype. Since tumor-driven stromal reactivities co-evolve in tumor progression and metastasis, it is not surprising that maspin expression in tumor cells inhibits extracellular matrix degradation, increases fibrosis and blocks hypoxia-induced angiogenesis. Using the athymic nude mouse model capable of supporting the growth and progression of xenogeneic human prostate cancer cells, we further demonstrate that maspin expression in tumor cells elicits neutrophil- and B cells-dependent host tumor immunogenicity. Specifically, mice bearing maspin-expressing tu...

Experimental Biology and Medicine, 2002

Epidemiological studies have shown an inverse association between dietary intake of lycopene and ... more Epidemiological studies have shown an inverse association between dietary intake of lycopene and prostate cancer risk. We conducted a clinical trial to investigate the biological and clinical effects of lycopene supplementation in patients with localized prostate cancer. Twenty-six men with newly diagnosed prostate cancer were randomly assigned to receive a tomato oleoresin extract containing 30 mg of lycopene (n = 15) or no supplementation (n = 11) for 3 weeks before radical prostatectomy. Biomarkers of cell proliferation and apoptosis were assessed by Western blot analysis in benign and cancerous prostate tissues. Oxidative stress was assessed by measuring the Peripheral blood lymphocyte ONA oxidation product 5-hydroxymethyl-deoxyuridine (5-OH-mdU). Usual dietary Intake of nutrients was assessed by a food frequency questionnaire at baseline. Prostatectomy specimens were evaluated for pathologic stage, Gleason score, volume of cancer, and extent of high-grade prostatic intraepithel...

Cancer research, Feb 6, 2016

Maspin (SerpinB5) is an epithelial-specific tumor suppressor gene product that displays context-d... more Maspin (SerpinB5) is an epithelial-specific tumor suppressor gene product that displays context-dependent cellular functions. Maspin-deficient mouse models created to date have not definitively established maspin functions critical for cancer suppression. In this study, we generated a mouse strain in which exon 4 of the Maspin gene was deleted, confirming its essential role in development but also enabling a breeding scheme to bypass embryonic lethality. Phenotypic characterization of this viable strain established that maspin deficiency was associated with a reduction in maximum body weight and a variety of context-dependent epithelial abnormalities. Specifically, maspin-deficient mice exhibited pulmonary adenocarcinoma, myoepithelial hyperplasia of the mammary gland, hyperplasia of luminal cells of dorsolateral and anterior prostate, and atrophy of luminal cells of ventral prostate and stratum spinosum of epidermis. These cancer phenotypes were accompanied by increased inflammator...

Bosnian journal of basic medical sciences / Udruženje basičnih mediciniskih znanosti = Association of Basic Medical Sciences, Jan 25, 2015

Despite the promising clinical outcome, the primary challenge of the curative cancer immunotherap... more Despite the promising clinical outcome, the primary challenge of the curative cancer immunotherapy is to overcome the dichotomy of the immune response: tumor-evoked immunostimulatory versus tumor-induced immunosuppressive. The goal needs to be two-fold, to re-establish sustainable antitumor-cancer immunity and to eliminate immunosuppression. The successful elimination of cancer cells by immunosurveillance requires the antigenic presentation of the tumor cells or tumor-associated antigens and the expression of immunostimulatory cytokines and chemokines by cancer and immune cells. Tumors are heterogeneous and as such, some of the tumor cells are thought to have stem cell characteristics that enable them to suppress or desensitize the host immunity due to acquired epigenetic changes. A central mechanism underlying tumor epigenetic instability is the increased histone deacetylase (HDAC)-mediated repression of HDAC-target genes regulating homeostasis and differentiation. It was noted tha...

Reviews in urology, 2003

The 13th International Prostate Cancer Update was held in Vail, Colorado, in February 2003. This ... more The 13th International Prostate Cancer Update was held in Vail, Colorado, in February 2003. This article provides an overview of the high points in the areas of complementary medicine, chemoprevention, and staging that were discussed at this meeting. M. Scott Lucia, MD, addressed the use of various hormonal agents, antiproliferative or differentiating agents, antiinflammatory agents, and antioxidants in patients with prostate cancer. Wael A. Sakr, MD, provided an overview of prognostic markers for this disease. Arturo Mendoza-Valdes, MD, explored the potential role of exercise for patients with prostate cancer, and Bruce Sodee, MD, described some exciting new developments in prostate imaging. E. David Crawford, MD, discussed the ongoing Prostate Cancer Prevention Trial.

Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology, 2001

An inverse association has been observed between dietary intake of lycopene and the risk of prost... more An inverse association has been observed between dietary intake of lycopene and the risk of prostate cancer. We investigated the effects of lycopene supplementation in patients with prostate cancer. Twenty-six men with newly diagnosed, clinically localized (14 T(1) and 12 T(2)) prostate cancer were randomly assigned to receive 15 mg of lycopene (n = 15) twice daily or no supplementation (n = 11) for 3 weeks before radical prostatectomy. Biomarkers of differentiation and apoptosis were assessed by Western blot analysis on benign and malignant parts of the prostate gland. Prostatectomy specimens were entirely embedded, step-sectioned, and evaluated for pathological stage, Gleason score, volume of cancer, and extent of high-grade prostatic intraepithelial neoplasia. Plasma levels of lycopene, insulin-like growth factor-1 (IGF-1), IGF binding protein-3, and prostate-specific antigen were measured at baseline and after 3 weeks of supplementation or observation. Eleven (73%) subjects in t...

Cancer research, 1997

Research into molecular and cellular defects underlying prostate cancer would be advanced by in v... more Research into molecular and cellular defects underlying prostate cancer would be advanced by in vitro models of prostate tumor cells representing patient tumors. We have propagated, in serum-free medium, epithelial cell cultures derived from nondiploid prostate tumors and normal human prostate. The serial passage tumor cells exhibited nondiploid karyotype and transformed phenotypes of focus formation and anchorage-independent growth. In contrast, the normal prostate cells showed diploid karyotype and lacked transformed phenotypes. Both the tumor and normal cells were positive for prostate-specific antigen and cytokeratins 18 and 19 and negative for keratin 15. These results demonstrate that the nondiploid prostate tumors and normal prostate epithelial cell cultures retained their respective in vivo properties and should allow studies to elucidate molecular alterations involved in human prostate cancer.

Cancer research, Jan 15, 1993

The putative tumor suppressor gene DCC has been shown to be frequently lost or expressed at low l... more The putative tumor suppressor gene DCC has been shown to be frequently lost or expressed at low levels in colorectal, gastric, pancreatic, and esophageal carcinomas. In the present study, the DCC gene and its mRNA expression in human and rat prostatic carcinoma cells as well as in prostatic carcinoma tissues were examined by reverse transcriptase-polymerase chain reaction and polymerase chain reaction-loss of heterozygosity. The DCC gene was present and expressed in normal prostatic cells. However, its expression was decreased or undetectable in all prostatic carcinoma cells from either humans (4 cell lines) or rats (5 cell lines). In patients, 12 of 14 cases (86%) showed reduced DCC expression and 5 of 11 informative cases (45%) showed loss of heterozygosity at the DCC locus. These results demonstrate that loss of DCC expression and loss of heterozygosity at the DCC locus are a frequent feature of prostatic carcinoma cells.

Cancer research, Jan 15, 1994

In order to determine whether retention or loss of potential tumor suppressor loci that map to 8p... more In order to determine whether retention or loss of potential tumor suppressor loci that map to 8p, 10q, or 16q reflect genetic relationships among prostatic intraepithelial neoplasias (PINs), multicentric primary prostatic cancers, and regional lymph node metastases or are associated with the metastatic phenotype, we analyzed 19 cases of locally metastatic prostate carcinoma (stage D1) utilizing polymerase chain reaction techniques. In each case, tissue samples from metastatic tumor, the (dominant) primary tumor, and nonneoplastic prostatic tissue were examined. In selected cases, allelic loss in additional tumor foci, separate from the dominant tumor nodule, and areas of PIN were examined. Allelic loss of sequences on 8p, 10q, and 16q were observed in 20-29% of PINs, 18-42% of primary tumors, and 8-25% of metastatic tumors. Discrepancies in sequence dosage between histological components were most pronounced for 8p sequences, especially between the dominant tumor nodule and metasta...

The Prostate, 2015

The mechanism(s) by which androgen receptor (AR) splice variants contribute to castration-resista... more The mechanism(s) by which androgen receptor (AR) splice variants contribute to castration-resistant prostate cancer (CRPC) is still lacking. Expressions of epithelial-to-mesenchymal transition (EMT) and stem cell markers were molecularly tested using prostate cancer (PCa) cells transfected with AR and AR3 (also known as AR-V7) plasmids or siRNA, and also cultured cells under androgen deprivation therapy (ADT) condition. Cell migration, clonogenicity, sphere-forming capacity was assessed using PCa cells under all experimental conditions and 3,3'-diindolylmethane (DIM; BR-DIM) treatment. Human PCa samples from BR-DIM untreated or treated patients were also used for assessing the expression of AR3 and stem cell markers. Overexpression of AR led to the induction of EMT phenotype, while overexpression of AR3 not only induced EMT but also led to the expression of stem cell signature genes. More importantly, ADT enhanced the expression of AR and AR3 concomitant with up-regulated expres...

Genes & cancer, 2011

Maspin is an epithelial-specific tumor suppressor gene. Previous data suggest that maspin express... more Maspin is an epithelial-specific tumor suppressor gene. Previous data suggest that maspin expression may redirect poorly differentiated tumor cells to better differentiated phenotypes. Further, maspin is the first and only endogenous polypeptide inhibitor of histone deacetylase 1 (HDAC1) identified thus far. In the current study, to address what central program of tumor cell redifferentiation is regulated by maspin and how tumor microenvironments further define the effects of maspin, we conducted a systematic and extensive comparison of prostate tumor cells grown in 2-dimensional culture, in 3-dimensional collagen I culture, and as in vivo bone tumors. We showed that maspin was sufficient to drive prostate tumor cells through a spectrum of temporally and spatially polarized cellular processes of redifferentiation, a reversal of epithelial-to-mesenchymal transition (EMT). Genes commonly regulated by maspin were a small subset of HDAC target genes that are closely associated with epit...

PLoS ONE, 2012

The emergence of castrate-resistant prostate cancer (CRPC) contributes to the high mortality of p... more The emergence of castrate-resistant prostate cancer (CRPC) contributes to the high mortality of patients diagnosed with prostate cancer (PCa), which in part could be attributed to the existence and the emergence of cancer stem cells (CSCs). Recent studies have shown that deregulated expression of microRNAs (miRNAs) contributes to the initiation and progression of PCa. Among several known miRNAs, let-7 family appears to play a key role in the recurrence and progression of PCa by regulating CSCs; however, the mechanism by which let-7 family contributes to PCa aggressiveness is unclear. Enhancer of Zeste homolog 2 (EZH2), a putative target of let-7 family, was demonstrated to control stem cell function. In this study, we found loss of let-7 family with corresponding over-expression of EZH2 in human PCa tissue specimens, especially in higher Gleason grade tumors. Overexpression of let-7 by transfection of let-7 precursors decreased EZH2 expression and repressed clonogenic ability and sphere-forming capacity of PCa cells, which was consistent with inhibition of EZH2 39UTR luciferase activity. We also found that the treatment of PCa cells with BR-DIM (formulated DIM: 3,39diindolylmethane by Bio Response, Boulder, CO, abbreviated as BR-DIM) up-regulated let-7 and down-regulated EZH2 expression, consistent with inhibition of self-renewal and clonogenic capacity. Moreover, BR-DIM intervention in our ongoing phase II clinical trial in patients prior to radical prostatectomy showed upregulation of let-7 consistent with downregulation of EZH2 expression in PCa tissue specimens after BR-DIM intervention. These results suggest that the loss of let-7 mediated increased expression of EZH2 contributes to PCa aggressiveness, which could be attenuated by BR-DIM treatment, and thus BR-DIM is likely to have clinical impact.

Urology, 2001

Prostate cancer chemoprevention represents a relatively new and promising strategy for reducing t... more Prostate cancer chemoprevention represents a relatively new and promising strategy for reducing the immense public health burden of this devastating cancer of men in the United States and Western societies. Chemoprevention is defined as the administration of agents (drugs, biologics, and natural products) that modulate (inhibit) one or more steps in the multistage carcinogenesis process culminating in invasive adenocarcinoma of the prostate. In 2000, there were an estimated 170,000 new cases of prostate cancer and 31,000 deaths in the United States. During the past decade, the National Cancer Institute (NCI) organized the chemoprevention research program and began testing the first generation of promising agents (eg, 4-(hydroxy)-fenretinide [4-HPR], difluoromethylornithine [DFMO], antiandrogens) in high-risk cohorts and launched the first-large scale US phase 3 primary prevention trial, known as Prostate Cancer Prevention Trial (PCPT-1), in 18,000 average-risk men (age more than 55 years and prostate-specific antigen [PSA] less than 3 ng/mL) treated for 7 years with finasteride or placebo. In the summer of 1998, the NCI Prostate Cancer Progress Review Group (PRG) Report to the director of NCI was published in response to the leadership of the prostate cancer advocacy community in conjunction with Congress. To further elucidate and address critical issues identified in this report and to develop a research agenda for the newly created Prostate and Urologic Cancer Research Group in the Division of Cancer Prevention at NCI, the NCI organized the workshop "New Clinical Trial Strategies for Prostate Cancer Chemoprevention." The major objectives were to promote understanding and cooperation among the NCI, US Food and Drug Administration (FDA), academia, pharmaceutical industry, and the public regarding new opportunities for clinical prevention trials for prostate cancer. The workshop was divided into three concurrent breakout panels and a fourth joint integrative panel. The workshop addressed multiple key areas identified in the PRG report in the following panels: (1) Molecular Targets and Promising Agents in Clinical Development; (2) Intermediate Endpoint Biomarkers for Prevention Trials; (3) High-Risk Study Populations for Prevention Trials, and (4) Preventive Clinical Trial Designs and Regulatory Issues. Expert panelists were drawn from leading academic, pharmaceutical, and government scientists in basic research and clinical investigation. Key pharmaceutical, biotechnology, academic, and National Institutes of Health scientists presented overviews of their new agents and products in clinical development (representing the next generation of promising agents). Senior FDA physicians from the Center for Drugs and Center for Biologics presented on current standards for new drug and biologic approval for chemoprevention efficacy. Some of the key topics included recent advances in the state of knowledge of promising agents in the clinic based on molecular targets as well as bottlenecks in drug development for pharmaceutical sponsors; strategic modulable biomarkers that can serve as primary endpoints in phase 1/2 trials to assess preventive efficacy; high-risk cohorts with precancer (high-grade prostatic intraepithelial neoplasia) and representative clinical trial designs that are ready for immediate translation into efficient prevention trials, such as Bayesian sequential monitoring for early assessment of biologic activity and factorial designs for assessment of multiagent combinations. Finally, each expert panel generated recommendations for areas of future research emphasizing opportunities and infrastructure needs.

The Prostate, 1998

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Scandinavian Journal of Urology and Nephrology, 2000

High-grade prostatic intraepithelial neoplasia (PIN) is the most likely precursor of prostatic ca... more High-grade prostatic intraepithelial neoplasia (PIN) is the most likely precursor of prostatic carcinoma. PIN has a high predictive value as a marker for carcinoma, and its identification in biopsy specimens warrants repeat biopsy for concurrent or subsequent carcinoma. The only methods of detection are biopsy and transurethral resection; PIN does not significantly elevate serum PSA concentration or its derivatives, nor does it induce a palpable mass, and cannot be detected by ultrasound. Androgen deprivation therapy decreases the prevalence and extent of PIN, suggesting that this form of treatment may play a role in chemoprevention. Radiation therapy is also associated with a decreased incidence of PIN.

Pure and Applied Chemistry, 2002

Dietary intake of lycopene is associated with reduced risk of prostate cancer (PCa). We conducted... more Dietary intake of lycopene is associated with reduced risk of prostate cancer (PCa). We conducted a clinical trial in men with prostate cancer to investigate the biological and clinical effects of lycopene supplementation. Twenty-six men with prostate cancer were randomly assigned to receive a lycopene supplement or no supplement for three weeks before radical prostatectomy. Subjects in the intervention group (n = 15) were instructed to take a tomato oleoresin extract soft gel capsule (Lyc-O-Mato®, LycoRed Company, Beer Sheva, Israel) containing 15 mg lycopene, 1.5 mg phytoene, 1.5 mg phytofluene, and 5 mg tocopherol twice daily with meals. Prostatectomy specimens were evaluated for pathologic stage, Gleason score, volume of cancer, and extent of high-grade prostatic intraepithelial neoplasia (HGPIN). Biomarkers of cell proliferation and apoptosis were assessed by Western blot analysis in benign and cancerous tissue samples obtained from the prostatectomy specimens. Oxidative stress...

Prostate Cancer and Prostatic Diseases, 2005

The QM protein is a transcription cofactor inhibiting the activity of AP-1 transcription factors ... more The QM protein is a transcription cofactor inhibiting the activity of AP-1 transcription factors and is also a ribosomal protein participating in protein synthesis. While protein synthesis is known to be increased in many cancers, inhibition of AP-1 activity presumably suppresses development and growth of sex-hormone-regulated tumor cells. The present study is the first report on immunohistochemical data of QM in human prostatic tissues. Paraffin sections of human prostate cancer samples were immunohistochemically stained for QM. The staining scores were analyzed with the clinicopathologic data of the patients. QM protein expression was found in all normal prostate glands adjacent to prostate cancer and in various intraepithelial neoplasia (PIN). In prostate cancer, the staining intensity and stained areas were decreased, compared to the normal glands and PIN lesions; in high-grade tumors only some patches of tumor cells showed positivity. Intense (3 þ) staining was mostly observed in the Gleason grade three areas (48%) compared to grade 4 and 5 areas (22%), although both low and high-grade tumors showed similar percentages of weakly stained areas. Moreover, staining in prostatic adenocarcinoma was often topographically patchy and varied from negative or weak (1 þ) to intense (3 þ). There was an inverse correlation from normal to low-grade tumors and then to high-grade tumors. However, in high-grade tumors, the positive areas were mostly confined to peripheral aspects of tumors and were particularly strong in foci of perineural invasion. This preliminary study suggests that decreased QM expression may be associated with early development of prostate cancer, but later a high level of QM may facilitate progression of the tumors to a more aggressive phenotype.