The vulnerable primed cancer stem cells in disguise: demystifying the role of Maspin.

Epithelial-specific Maspin is widely known as a tumor suppressor. However, while the level of maspin expression is inversely correlated with tumor grade and stage, emerging clinical evidence shows a correlation between seemingly better differentiated tumor cells that express Maspin in both the nucleus and the cytoplasm, (n + c)Maspin, with a poor prognosis of many types of cancer. Biological studies demonstrate that Maspin plays an essential role in stem cell differentiation. In light of the recently established characterization of primed stem cells (P-SCs) in development, we propose, for the first time, that cancer stem cells (CSCs) also need to undergo priming (P-CSCs) before their transition to various progeny phenotypes. We envisage major differences in the steady state kinetics between P-SCs and P-CSCs. We further propose that P-CSCs of carcinoma are both marked and regulated by (n + c)Maspin. The concept of P-CSCs helps explain the apparent dichotomous relationships of (n + c)Maspin expression with cancer diagnosis and prognosis, and is supported by the evidence from mechanistic studies. We believe that the potential utility of (n + c)Maspin as a molecular marker of P-CSCs may significantly accelerate the advancement in our understanding of the genesis of tumor phenotypic plasticity in response to changes of tumor microenvironments (TME) or drug treatments. The vulnerabilities of the cellular state of (n + c)Maspin-expressing P-CSCs are also discussed as the rationale for future development of P-CSC-targeted chemotherapeutic and immunotherapeutic strategies.

Recurrent KRAS mutations are early events in the development of papillary renal neoplasm with reverse polarity.

We evaluated the clinicopathologic and molecular characteristics of mostly incidentally detected, small, papillary renal neoplasms with reverse polarity (PRNRP). The cohort comprised 50 PRNRP from 46 patients, divided into 2 groups. The clinically undetected (<5 mm) neoplasms (n = 34; 68%) had a median size of 1.1 mm (range 0.2-4.3 mm; mean 1.4 mm), and the clinically detected (≥5 mm) neoplasms (n = 16; 32%) which had a median size of 13 mm (range 9-30 mm; mean 16 mm). Neoplasms were positive for GATA3 (n = 47; 100%) and L1CAM (n = 34/38; 89%) and were negative for vimentin (n = 0/44; 0%) and, to a lesser extent, AMACR [(n = 12/46; 26%; weak = 9, weak/moderate = 3)]. KRAS mutations were found in 44% (n = 15/34) of the clinically undetected PRNRP and 88% of the clinically detected PRNRP (n = 14/16). The two clinically detected PRNRP with wild-type KRAS gene were markedly cystic and contained microscopic intracystic tumors. In the clinically undetected PRNRP, the detected KRAS mutations rate was higher in those measuring ≥1 mm vs <1 mm [n = 14/19 (74%) vs n = 1/15 (7%)]. Overall, the KRAS mutations were present in exon 2-codon 12: c.35 G > T (n = 21), c.34 G > T (n = 3), c.35 G > A (n = 2), c.34 G > C (n = 2) resulting in p.Gly12Val, p. Gly12Asp, p.Gly12Cys and p.Gly12Arg, respectively. One PRNRP had a G12A/V/D complex mutation. Twenty-six PRNRP were concurrently present with other tumors of different histologic subtypes in the ipsilateral kidney; molecular testing of 8 of the latter showed wild-type KRAS gene despite the presence of KRAS mutations in 5 concurrent PRNRP. On follow up, no adverse pathologic events were seen (range 1-160 months; mean 44 months). In conclusion, the presence of KRAS mutations in small, clinically undetected PRNRP provides a unique finding to this entity and supports its being an early event in the development of these neoplasms.

Recurrent KRAS mutations in papillary renal neoplasm with reverse polarity.

We recently proposed that an epithelial renal tumor "papillary renal neoplasm with reverse polarity" represents a distinct entity. It constituted 4% of previously diagnosed papillary renal cell carcinoma at the participating institutions. Histologically, it is characterized by papillary or tubulopapillary architecture covered by a single layer of eosinophilic cells with finely granular cytoplasm and apically located nuclei. It is characteristically positive for GATA3 and L1CAM and lack vimentin and, to a lesser extent, α-methylacyl-CoA-racemase (AMACR/p504s) immunostaining. To investigate the molecular pathogenesis of these tumors, we performed targeted next-generation sequencing on ten previously reported papillary renal neoplasms with reverse polarity, followed by a targeted polymerase chain reaction analysis for KRAS mutations in a control series of 30 type 1 and 2 papillary renal cell carcinomas. KRAS missense mutations were identified in eight of ten papillary renal neoplasms with reverse polarity. These mutations were clustered in exon 2-codon 12: c.35 G > T (n = 6) or c.34 G > C (n = 2) resulting in p.Gly12Val and p.Gly12Arg alterations, respectively. One of the wild-type tumors had BRAF c.1798_1799delGTinsAG (p.Val600Arg) mutation. No KRAS mutations were identified in any of the 30 control tumors. In summary, this study supports our proposal that papillary renal neoplasm with reverse polarity is an entity distinct from papillary renal cell carcinoma and the only renal cell neoplasm to consistently harbor KRAS mutations.

Tackling tumor heterogeneity and phenotypic plasticity in cancer precision medicine: our experience and a literature review.

The predominant cause of cancer mortality is metastasis. The major impediment to cancer cure is the intrinsic or acquired resistance to currently available therapies. Cancer is heterogeneous at the genetic, epigenetic, and metabolic levels. And, while a molecular-targeted drug may be pathway-precise, it can still fail to achieve wholesome cancer-precise toxicity. In the current review, we discuss the strategic differences between targeting the strengths of cancer cells in phenotypic plasticity and heterogeneity and targeting shared vulnerabilities of cancer cells such as the compromised integrity of membranous organelles. To better recapitulate subpopulations of cancer cells in different phenotypic and functional states, we developed a schematic combination of 2-dimensional culture (2D), 3-dimmensional culture in collagen I (3D), and mammosphere culture for stem cells (mammosphere), designated as Scheme 2D/3D/mammosphere. We investigated how the tumor suppressor maspin may limit carcinoma cell plasticity and affect their context-dependent response to drugs of different mechanisms including docetaxel, histone deacetylase (HDAC) inhibitor MS-275, and ionophore antibiotic salinomycin. We showed that tumor cell phenotypic plasticity is not an exclusive attribute to cancer stem cells. Nonetheless, three subpopulations of prostate cancer cells, enriched through Scheme 2D/3D/mammosphere, show qualitatively different drug responses. Interestingly, salinomycin was the only drug that effectively killed all three cancer cell subpopulations, irrespective of their capacity of stemness. Further, Scheme 2D/3D/mammosphere may be a useful model to accelerate the screening for curative cancer drugs while avoiding costly characterization of compounds that may have only selective toxicity to some, but not all, cancer cell subpopulations.

Androgen receptor splice variants contribute to prostate cancer aggressiveness through induction of EMT and expression of stem cell marker genes.

BACKGROUND: The mechanism(s) by which androgen receptor (AR) splice variants contribute to castration-resistant prostate cancer (CRPC) is still lacking. METHODS: 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. RESULTS: 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 expression of EMT and stem cell marker genes. Dihydrotestosterone (DHT) treatment decreased the expression of AR and AR3, and reversed the expression of these EMT and stem cell marker genes. BR-DIM administered to PCa patients prior to radical prostatectomy inhibited the expression of cancer stem cell markers consistent with inhibition of self-renewal of PCa cells after BR-DIM treatment. CONCLUSION: AR variants could contribute to PCa progression through induction of EMT and acquisition of stem cell characteristics, which could be attenuated by BR-DIM, suggesting that BR-DIM could become a promising agent for the prevention of CRPC and/or for the treatment of PCa.

SWOG S0353: Phase II trial of intravesical gemcitabine in patients with nonmuscle invasive bladder cancer and recurrence after 2 prior courses of intravesical bacillus Calmette-Guérin.

PURPOSE: Prior phase II studies of intravesical gemcitabine have shown it to be active and well tolerated, but durable responses in patients with nonmuscle invasive bladder cancer who have experienced recurrence after bacillus Calmette-Guérin treatment are uncommon. We performed a multi-institutional phase II study within the SWOG (Southwest Oncology Group) cooperative group to evaluate the potential role of gemcitabine induction plus maintenance therapy in this setting. MATERIALS AND METHODS: Eligible patients had recurrent nonmuscle invasive bladder cancer, stage Tis (carcinoma in situ), T1, Ta high grade or multifocal Ta low grade after at least 2 prior courses of bacillus Calmette-Guérin. Patients were treated with 2 gm gemcitabine in 100 cc normal saline intravesically weekly × 6 and then monthly to 12 months. Cystoscopy and cytology were performed every 3 months, with biopsy at 3 months and then as clinically indicated. Initial complete response was defined as negative cystoscopy, cytology and biopsy at 3 months. RESULTS: A total of 58 patients were enrolled in the study and 47 were evaluable for response. Median patient age was 70 years (range 50 to 88). Of the evaluable patients 42 (89%) had high risk disease, including high grade Ta in 12 (26%), high grade T1 in 2 (4%) and carcinoma in situ in 28 (60%) with or without papillary lesions. At the initial 3-month evaluation 47% of patients were free of disease. At 1 year disease had not recurred in 28% of the 47 patients, all except 2 from the high risk group, and at 2 years disease had not recurred in 21%. CONCLUSIONS: Intravesical gemcitabine has activity in high risk nonmuscle invasive bladder cancer and offers an option for patients with recurrence after bacillus Calmette-Guérin who are not suitable for cystectomy. However, less than 30% of patients had a durable response at 12 months even with maintenance therapy.

3,3'-Diindolylmethane enhances taxotere-induced growth inhibition of breast cancer cells through downregulation of FoxM1.

Emerging evidence suggests that the transcription factor Forkhead Box M1 (FoxM1) is associated with aggressive human carcinomas, including breast cancer. Because elevated expression of FoxM1 has been observed in human breast cancers, FoxM1 has attracted much attention in recent years as a potential target for the prevention and/or therapeutic intervention in breast cancer. However, no information is currently available regarding how downregulation of FoxM1 could be achieved for breast cancer prevention and therapy. Here, we report for the first time that 3,3'-diindolylmethane (DIM), a nontoxic dietary chemopreventive agent could effectively downregulate FoxM1 in various breast cancer cell lines. Using gene transfection, real-time reverse transcription-PCR, Western blotting, invasion and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, we found that DIM could enhance Taxotere-induced growth inhibition of breast cancer cells, and decreased invasive capacity of breast cancer cells was observed after either treatment alone or the combination. These effects were associated with downregulation of FoxM1. We also found that knock down of FoxM1 expression by small interfering RNA (siRNA) transfection increased DIM-induced cell growth inhibition, whereas over-expression of FoxM1 by cDNA transfection attenuated DIM-induced cell growth inhibition, suggesting the mechanistic role of FoxM1. Most importantly, the combination treatment significantly inhibited tumor growth in severe combined immunodeficiency (SCID) mice, and the results were correlated with the downregulation of FoxM1 in tumor remnants. We conclude that inactivation of FoxM1 and its target genes by DIM could enhance the therapeutic efficacy of Taxotere in breast cancer, which could be a useful strategy for the prevention and/or treatment of breast cancer.

Should all prostate needle biopsy Gleason score 4 + 4 = 8 prostate cancers be high risk? Implications for shared decision-making and patient counselling.

OBJECTIVES: To estimate the probability of downgrading to Gleason score ≤7 at radical prostatectomy for men with a prostate needle biopsy demonstrating Gleason score 8 (4 + 4). METHODS: This is a retrospective review of men with Gleason score 8 (4 + 4) prostate cancer on needle biopsy who then underwent a radical prostatectomy at the Karmanos Cancer Institute or the University of Michigan. Men with any pattern 5 on the diagnostic biopsy were excluded. The objective was to estimate the proportion of patients whose tumors were downgraded to Gleason score ≤7 at radical prostatectomy and to identify clinical and biopsy parameters associated with downgrading. RESULTS: Median age of our cohort was 63 years (IQR: 59, 67.5) and median follow-up was 15 months (IQR: 7, 37). Of the 105 men that met inclusion criteria, 59% (62/105) were downgraded to Gleason score ≤7 at radical prostatectomy. Having ≤2 cores demonstrating Gleason score 8, ≤50% maximal tumor involvement of any individual core positive for Gleason score 8, or the presence of Gleason pattern 3 (such as 3 + 4, 4 + 3, or 3 + 3) in other biopsy cores were all independently associated with downgrading in our multivariable model. Depending on the absence, presence, or combination of these 3 factors, patients had an estimated 6% to 82% probability of having their tumor downgraded at radical prostatectomy. CONCLUSIONS: Men with low volume Gleason 8 (4 + 4) and/or the presence Gleason pattern 3 on prostate needle biopsy often have their tumors downgraded at radical prostatectomy. The presence of these preoperative biopsy parameters could affect pretreatment counseling and impact patient management.

Papillary Renal Neoplasm With Reverse Polarity: A Morphologic, Immunohistochemical, and Molecular Study.

We evaluated the clinicopathologic and chromosomal characteristics of a distinct subset of papillary renal tumors and compared them to a control series of papillary renal cell carcinoma types 1 and 2. Of the 18 patients, 9 were women and 9 were men, ranging in age from 46 to 80 years (mean, 64 y; median, 66 y). The tumors ranged in diameter from 0.6 to 3 cm (mean, 1.63 cm; median, 1.4 cm). Fourteen tumors were WHO/ISUP grade 2 and 4 were grade 1. All were stage category pT1. The tumors had branching papillae with thin fibrovascular cores, covered by cuboidal to columnar cells with granular eosinophilic cytoplasm, smooth luminal borders, and mostly regular and apically located nuclei with occasional nuclear clearing and inconspicuous nucleoli. Tubule formation and clear cytoplasmic vacuoles were observed in 5 and 9 tumors, respectively. Ten tumors had pseudocapsules. Psammoma bodies, necrosis, mitotic figures and intracellular hemosiderin are absent from all tumors. In contrast, papillary renal cell carcinoma type 1 consisted of delicate papillae covered by a single layer of cells with scanty pale cytoplasm with nuclei generally located in a single layer on the basement membrane of the papillary cores, while type 2 tumors had broad papillae covered by pseudostratified cells with eosinophilic cytoplasm and more randomly located nuclei. Both had occasional psammoma bodies, foamy macrophages and intracellular hemosiderin. Immunohistochemically, all were positive for pancytokeratin AE1/AE3, epithelial membrane antigen, MUC1, CD10, GATA3, and L1CAM. Cytokeratin 7 was positive in 16 tumors (1 had <5% positivity). CD117 and vimentin were always negative. α-methylacyl-CoA-racemase (AMACR/p504s) showed variable staining (range, 10% to 80%) in 5 tumors. However, all tumors in the control group were negative for GATA3 and positive for AMACR/p504s and vimentin immunostains. Fluorescence in situ hybridization analysis of the study group demonstrated chromosome 7 trisomy in 5 tumors (33%), trisomy 17 in 5 tumors (33%), and trisomy 7 and 17 in 3 tumors (20%). Chromosome Y deletion was found in 1 of 7 male patients and chromosome 3p was present in all tumors. No tumor recurrence or metastasis occurred. In summary, we propose the term papillary renal neoplasm with reverse polarity for this entity.

Inactivation of NF-kappaB by 3,3'-diindolylmethane contributes to increased apoptosis induced by chemotherapeutic agent in breast cancer cells.

Constitutive activation of Akt or nuclear factor-kappaB (NF-kappaB) has been reported to play a role in de novo resistance of cancer cells to chemotherapeutic agents, which is a major cause of treatment failure in cancer chemotherapy. Previous studies have shown that 3,3'-diindolylmethane (DIM), a major in vivo acid-catalyzed condensation product of indole-3-carbinol, is a potent inducer of apoptosis, inhibitor of tumor angiogenesis, and inactivator of Akt/NF-kappaB signaling in breast cancer cells. However, little is known regarding the inactivation of Akt/NF-kappaB that leads to chemosensitization of breast cancer cells to chemotherapeutic agents, such as Taxotere. Therefore, we examined whether the inactivation Akt/NF-kappaB signaling caused by B-DIM could sensitize breast cancer cells to chemotherapeutic agents both in vitro and in vivo. MDA-MB-231 cells were simultaneously treated with 15 to 45 micromol/L B-DIM and 0.5 to 1.0 nmol/L Taxotere for 24 to 72 h. Cell growth inhibition assay, apoptosis assay, electrophoretic mobility shift assay, and Western blotting were done. The combination treatment of 30 micromol/L B-DIM with 1.0 nmol/L Taxotere elicited significantly greater inhibition of cell growth compared with either agent alone. The combination treatment induced greater apoptosis in MDA-MB-231 cells compared with single agents. Moreover, we found that NF-kappaB activity was significantly decreased in cells treated with B-DIM and Taxotere. We also have tested our hypothesis using transfection studies, followed by combination treatment with B-DIM/Taxotere, and found that combination treatment significantly inhibited cell growth and induced apoptosis in MDA-MB-231 breast cancer cells mediated by the inactivation of NF-kappaB, a specific target in vitro and in vivo. These results were also supported by animal experiments, which clearly showed that B-DIM sensitized the breast tumors to Taxotere, which resulted in greater antitumor activity mediated by the inhibition of Akt and NF-kappaB. Collectively, our results clearly suggest that inhibition of Akt/NF-kappaB signaling by B-DIM leads to chemosensitization of breast cancer cells to Taxotere, which may contribute to increased growth inhibition and apoptosis in breast cancer cells. The data obtained from our studies could be a novel breakthrough in cancer therapeutics by using nontoxic agents, such as B-DIM, in combination with other conventional therapeutic agents, such as Taxotere.

Overexpression of the Pluripotent Stem Cell Marker Podocalyxin in Prostate Cancer.

BACKGROUND/AIM: Podocalyxin, a member of the CD34 family of cell surface sialomucins, is overexpressed in human embryonal carcinoma cell lines, as well as in several cancer types, and is associated with poor prognosis. Podocalyxin variants are associated with an increased risk and aggressiveness of prostate cancer. Herein podocalyxin protein expression in prostate cancer was characterized. MATERIALS AND METHODS: Expression of podocalyxin as well as of TRA-1-60 and TRA-1-81 antigens was assessed immunohistochemically in 84 radical prostatectomy specimens and in adjacent normal tissues. RESULTS: Podocalyxin expression and H-scores were considerably higher in prostate tumors compared to normal tissues. High TRA-1-60 and TRA-1-81 staining was detected, however, in a much smaller percentage of prostate tumors, while their expression and H-scores were low in normal tissues. Similar trends for all three proteins were observed in prostatic intraepithelial neoplasia. CONCLUSION: Overexpression of podocalyxin in prostate cancer renders the protein a putative immunohistochemical marker of prostate cancer that may contribute to stratification of patients for optimal treatment.

Transoral carbon dioxide laser supraglottic laryngectomy and irradiation in stage I, II, and III squamous cell carcinoma of the supraglottic larynx: report of Southwest Oncology Group Phase 2 Trial S9709.

OBJECTIVE: To evaluate feasibility, functional outcome, and disease control of endoscopic surgery and irradiation in patients with squamous cell carcinoma of the supraglottic larynx. DESIGN: Prospective, single-arm, phase 2 multi-institutional trial. SETTING: Southwest Oncology Group trial S9709. PATIENTS: Thirty-four patients diagnosed as having stage I, stage II, or selected stage III (T1-2N1M0) supraglottic laryngeal carcinoma enrolled from September 15, 1997, to December 1, 2001. INTERVENTIONS: Transoral supraglottic laryngectomy by carbon dioxide laser followed by planned postoperative radiotherapy. MAIN OUTCOME MEASURES: Three-year progression-free survival, proportion of patients requiring tracheostomy as a result of surgery, and time to adequate oral intake. RESULTS: All 34 patients underwent surgery without major protocol deviation. Thirty-two patients (94%) completed planned postoperative radiotherapy without major deviation. At the time of analysis, only 1 patient (3%) had documented local disease recurrence at the primary disease site and required salvage total laryngectomy, and 2 patients (6%) had documented regional recurrence and required salvage neck dissection. Estimated 3-year progression-free survival and overall survival were 79% and 88%, respectively. No subjects required tracheostomy as a direct consequence of endoscopic resection. Patients who required tracheostomy before endoscopic resection due to either obstructive tumor bulk or unfavorable anatomy that precluded safe intubation (4 patients [12%]) were all decannulated in the early postoperative period (

An Essential Role of Maspin in Embryogenesis and Tumor Suppression.

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 inflammatory stroma. These mice also displayed the autoimmune disorder alopecia aerate. Overall, our findings defined context-specific tumor suppressor roles for maspin in a clinically relevant model to study maspin functions in cancer and other pathologies. Cancer Res; 77(4); 886-96. ©2017 AACR.

Ixabepilone (epothilone B analogue BMS-247550) is active in chemotherapy-naive patients with hormone-refractory prostate cancer: a Southwest Oncology Group trial S0111.

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 frequent grade 3 AEs were neuropathy (eight patients), hematologic toxicity (seven patients), flu-like symptoms, and infection (five patients each). There were no grade 3/4 thrombocytopenia or grade 5 AEs. There were 14 confirmed PSA responses (33%; 95% CI, 20% to 50%); 72% of PSA responders had declines greater than 80%, and two patients achieved an undetectable PSA. The estimated median progression-free survival is 6 months (95% CI, 4 to 8 months), and the median survival is 18 months (95% CI, 13 to 24 months). CONCLUSION: Ixabepilone has demonstrated activity in patients with chemotherapy-naive metastatic HRPC. Major toxicities were neutropenia and neuropathy. Further testing to define its activity relative to standard therapy is warranted.

Anti-androgenic activity of absorption-enhanced 3, 3'-diindolylmethane in prostatectomy patients.

Consumption of cruciferous vegetables is associated with a decreased risk of developing prostate cancer. Antineoplastic effects of cruciferous vegetables are attributable to bioactive indoles, most prominently, 3, 3'-diindolylmethane (DIM). In addition to effects on proliferation and apoptosis, DIM acts as an antiandrogen in prostate cancer cell lines. This study characterized the effects of prostatic DIM on the androgen receptor (AR) in patients with prostate cancer. Men with localized prostate cancer were treated with a specially formulated DIM capsule designed for enhanced bioavailability (BR-DIM) at a dose of 225 mg orally twice daily for a minimum of 14 days. DIM levels and AR activity were assessed at the time of prostatectomy. Out of 28 evaluable patients, 26 (93%) had detectable prostatic DIM levels, with a mean concentration of 14.2 ng/gm. The mean DIM plasma level on BR-DIM therapy was 9.0 ng/mL; levels were undetectable at baseline and in follow-up samples. AR localization in the prostate was assessed with immunohistochemistry. After BR-DIM therapy, 96% of patients exhibited exclusion of the AR from the cell nucleus. In contrast, in prostate biopsy samples obtained prior to BR-DIM therapy, no patient exhibited AR nuclear exclusion. Declines in PSA were observed in a majority of patients (71%). Compliance was excellent and toxicity was minimal. In summary, BR-DIM treatment resulted in reliable prostatic DIM levels and anti-androgenic biologic effects at well tolerated doses. These results support further investigation of BR-DIM as a chemopreventive and therapeutic agent in prostate cancer.

Treatment and prevention of intraepithelial neoplasia: an important target for accelerated new agent development.

Precancer or intraepithelial neoplasia (IEN) is a noninvasive lesion that has genetic abnormalities, loss of cellular control functions, and some phenotypic characteristics of invasive cancer and that predicts for a substantial likelihood of developing invasive cancer. The AACR Task Force on the Treatment and Prevention of IEN has delineated the relationship between IEN and cancer risk as well as the clinical benefit that can be derived from reducing IEN burden. Although several effective endoscopic and surgical treatments for IEN have become standard medical practice, these interventions can confer morbidity and do not treat the entire epithelial field at risk. The incidence of many epithelial cancers is continuing to rise, the number of individuals at risk is increasing with the aging population, and the rapid advancement of imaging and molecular diagnostics is bringing to light precancers that were heretofore clinically silent. There is therefore an urgent need to rapidly develop new treatment and prevention agents for IEN. The AACR IEN Task Force recommends focusing on established precancers as the target for new agent development because of the close association between dysplasia and invasive cancer and because a convincing reduction in IEN burden provides patient benefit by reducing cancer risk and/or by decreasing the need for invasive interventions. The IEN Task Force proposes several clinical trial designs that provide practical and feasible approaches to the rapid development of new agents to treat and prevent precancer.

WITHDRAWN:Epidemiology of prostate cancer and its precursors.

Ahead of Print article withdrawn by publisher.

Management of clinical T1 bladder transitional cell carcinoma by radical cystectomy.

High-grade bladder cancer involving the lamina propria is considered superficial disease. This spectrum is generally treated with TUR plus intravesical therapy. However, significant understaging jeopardizes long-term survival and improvements and radical surgery represents a provocative alternative. We evaluated disease-free and cancer-specific survival (CSS) in our cohort of patients with high-grade T1 tumors. A total of 318 patients with bladder cancer underwent radical cystectomy between 1990 and 2000 at our institution. Of these, 66 had cT1 tumors with or without Carcinoma in-situ (CIS). Our multidisciplinary bladder cancer database was queried to perform a multivariate analysis on clinical parameters such as: age, race, sex, cystectomy year, intravesical therapy, angiolymphatic-invasion and tumor upstage in relation to recurrence and survival. The clinical stage was accurate in 44 of the cases (66%). However, 27% were upstaged by cystectomy and 12% of the cT1 + CIS patients had nodal disease. Patients with cT1 tumors plus CIS had a significantly worse CSS. Those with persistent disease after an initial course of BCG therapy appeared to have worse CSS also. At a median follow up of 4 years, overall cancer-specific mortality was 22%, however, pathologic T1 +/- CIS had 92% CSS at 10 years. Our data suggests that some cT1 bladder cancer tumors have assiduous clinical courses evidenced in staging discrepancies. For high-grade tumors, early cystectomy and orthotopic diversion increases life expectancy significantly and should be carry out early rather than late.

Potential pathologic markers for prostate chemoprevention studies.

The field of exploring potential biomarkers for prostate cancer prevention continues to expand rapidly. In addition to a limited scope of histologic alterations, mainly PIN, a growing array of promising technologies (eg, computer-assisted analysis), and molecules involved in cell-cycle regulations, angiogenesis, and structural and numerical chromosomal alterations are potential candidates for surrogate endpoint biomarkers for prevention trials. Before any these potential candidates are adopted, however, the technical, interpretational, and validation requirements must be satisfied. More important, it is crucial to demonstrate that modulation of the frequency of the biomarker decreases the rate of cancer development.

Quantification of G250 mRNA expression in renal epithelial neoplasms by real-time reverse transcription-PCR of dissected tissue from paraffin sections.

AIM: Renal cell carcinoma (RCC) represents the most common malignant tumour in the kidney and is resistant to conventional therapies. G250 is a tumour-associated antigen and is expressed mainly in clear cell RCC. It is a potential therapeutic target as well as a diagnostic marker for RCC. Previous studies relating to G250 protein or G250 mRNA expression in RCC using human tissue have largely been limited to immunohistochemical or conventional RT-PCR approaches that lack reproducibility, are subject to observer bias and are at most semi-quantitative. In this study, we evaluated the feasibility of using real-time RT-PCR in quantifying G250 mRNA expression using tissue dissected from paraffin sections of renal epithelial neoplasms. Using this approach, we performed a preliminary study investigating the relationship between G250 expression and tumor behavior in clear cell RCC. METHODS: A total of 53 radical nephrectomy specimens with renal epithelial neoplasms (nine oncocytoma, seven chromophobe RCC, four papillary RCC and 33 clear cell RCC) were included in this study. SYBR Green real-time RT-PCR was performed using the ABI PRISM 7700 Sequence Detection System. A TATA box-binding protein (TBP) was used as an endogenous reference gene. RESULTS: Our study showed that real-time RT-PCR is a reliable approach in quantifying G250 mRNA expression using paraffin sections. Using this methodology, G250 mRNA was detected in all of the clear cell RCCs, but none of the other types of tumours studied or in normal kidney tissue. Our study also suggested that the expression of G250 mRNA might correlate with tumour stage and overall survival. CONCLUSION: Among common renal epithelial neoplasms, G250 is a specific marker for clear cell RCC. Quantification of G250 mRNA expression by real-time RT-PCR using paraffin sections is a feasible approach for future clinical studies in evaluating the prognostic and predictive value of G250 in clear cell RCC.