Alveolar bone histological necrosis observed prior to extractions in patients, who received bone-targeting agents.

OBJECTIVE: We reported the alveolar bone histology prior to dental extractions in cancer patients, who received bone-targeting agents (BTA). SUBJECTS AND METHODS: Fifty-four patients were included. Patients underwent extractions, and bone biopsies were taken. RESULTS: Extractions were performed due to pain, swelling, purulence, fistula, and numbness, not responding to treatment, in 40 patients (group A); extractions due to asymptomatic, non-restorable teeth, were performed in 14 patients (group B). Complete alveolar jaw bone histological necrosis was observed in 28 of 40 (70%) patients of group A and none of group B (p < .001). The development of clinical osteonecrosis (MRON) was assessed in 44 patients; 10 patients, who were also treated with Low Level Laser Treatments-LLLT, were excluded from this analysis, as the alternative therapies were a confounding factor. Twelve patients, with alveolar bone histological necrosis prior to extraction, developed medication-related osteonecrosis of the jaw (MRONJ) compared with two patients with vital or mixed vital/non-vital bone (p < .0007). BTAs >1 year and concurrent targeted therapy were also significantly associated with MRONJ (p = .016 and p = .050). CONCLUSION: Pain, swelling, purulence, fistula, and numbness were significantly associated with complete bone histological necrosis prior to extractions and increased MRONJ development. Research is justified to explore whether histological necrosis represents an early stage of osteonecrosis.

Microsatellite Instability Is Insufficiently Used as a Biomarker for Lynch Syndrome Testing in Clinical Practice.

PURPOSE: The pan-cancer presence of microsatellite instability (MSI)-positive tumors demonstrates its clinical utility as an agnostic biomarker for identifying immunotherapy-eligible patients. Additionally, MSI is a hallmark of Lynch syndrome (LS), the most prevalent cancer susceptibility syndrome among patients with colorectal and endometrial cancer. Therefore, MSI-high results should inform germline genetic testing for cancer-predisposing genes. However, in clinical practice, such analysis is frequently disregarded. METHODS: A next-generation sequencing (NGS)-based technique was used for MSI analysis in 4,553 patients with various tumor types. Upon request, somatic BRAF gene analysis was conducted. In addition, hereditary testing of cancer-associated genes was performed in MSI-high cases using a capture-based NGS protocol. MLH1 promoter methylation analysis was conducted retrospectively in patients with colorectal and endometrial cancer to further investigate the origin of MSI at the tumor level. RESULTS: The MSI positivity rate for the entire cohort was 5.27%. Endometrial, gastric, colorectal, urinary tract, and prostate cancers showed the highest proportion of MSI-high cases (15.69%, 8.54%, 7.40%, 4.55%, and 3.19%, respectively). A minority of 45 patients (22.73%) among the MSI-high cases underwent germline testing to determine whether the mismatch repair pathway deficiency was inherited. 24.44% of those who performed the genetic test carried a pathogenic variant in an LS-associated gene. Three MSI-high individuals had non-LS gene alterations, including BRCA1, BRCA2, and CDKN2A pathogenic variants, indicating the presence of non-LS-associated gene alterations among MSI-high patients. CONCLUSION: Although MSI analysis is routinely performed in clinical practice, as many as 77% of MSI-high patients do not undergo LS genetic testing, despite international guidelines strongly recommending it. BRAF and MLH1 methylation analysis could shed light on the somatic origin of MSI in 42.50% of the MSI-high patients; however, MLH1 analysis is barely ever requested in clinical practice.

The Impact of Enhanced Recovery after Surgery Protocol Implementation on Postoperative Pain Management in the Era of Opioid Crisis: The Postchemotherapy Open RPLND Experience.

AIM: Enhanced Recovery After Surgery (ERAS) protocols have been proven to optimize postoperative outcomes; however, misuse of opioid analgesics can still hinder postoperative recovery due to related side effects and potential complications. INTRODUCTION: To determine if the implementation of ERAS protocol in post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND) patients could help with reducing postoperative pain and opioid use. METHODS: A case-control study of consecutive testicular cancer patients with indications for PCRLPND, who were offered Conventional Post-operative Management (CPM) or ERAS protocol. Outcomes of interest included Visual Analogue Scale (VAS)-assessed pain level at postoperative days 3, 7, and 30, and Morphine-Equivalent Doses (MEDs)/postoperative day. Intraoperative parameters and postoperative complications were recorded. Parametric and non-parametric tests were used for statistical analysis. RESULTS: In total, 100 opioid-naïve PC-RPLND patients were studied. CPM and ERAS groups (36 and 64 patients, respectively) had similar demographic and baseline clinical characteristics). ERAS group patients had significantly lower blood loss (p = 0.005), blood transfusion rate (p < 0.001), and duration of the procedure (p < 0.001). Post-operative complications were comparable between groups. Nausea and bowel disorders were numerically but not statistically more frequent in the CPM group. ERAS patients had shorter mean hospital stay (5.3 ± 1.4 vs. 7.4 ± 1.6 days, p < 0.001), lower daily MEDs (4.73 ± 2.63 vs. 7.04 ± 2.29, p < 0.001), and lower VAS scores on post-operative day 7 (3.89 ± 1.07 vs. 4.67 ± 1.17, p = 0.001). Post-operative pain was similar between groups on post-operative days 3 and 30. CONCLUSION: Systematic implementation of ERAS protocol after PC-RPLND improves pain management, optimizes patient recovery, and prevents over-prescription of opioid analgesics.

Lack of prognostic significance of p16 and p27 after radical prostatectomy in hormone-naïve prostate cancer.

BACKGROUND: Loss of normal cell cycle control is an early event in the evolution of cancer. The expression of cyclin-dependent kinase (CDK) inhibitors p16 and p27 has been previously associated with progression of prostate cancer (PC). 70 patients diagnosed with early stage PCwere treated with radical prostatectomy (RP) at our institution and their tumor specimens were immunohistochemically evaluated for expression of p16 and p27. Available clinical data of time to PSA recurrence were correlated with the examined parameters and combined with pre-operative PSA level, Gleason score and pathological TNM (pT) stage assessment. RESULTS: Nuclear overexpression of p16 was not associated with time to biochemical failure (BF) (p = 0.572). Same was the case for nuclear p27 overexpression (p = 1.000). Also, no significant correlations were found between either p16 or p27, and pre-operative PSA level, pT stage and Gleason grade. pT stage emerged as the only independent prognostic factor for biochemical recurrence (p = 0.01). CONCLUSIONS: These data question previously reported data supporting the prognostic relevance of both p16 and p27 proteins in early PC.

CD10 is inversely associated with nuclear factor-kappa B and predicts biochemical recurrence after radical prostatectomy.

INTRODUCTION: The cell surface endopeptidase CD10 (neutral endopeptidase) and nuclear factor-κB (NF-κB) have been independently associated with prostate cancer (PC) progression. We investigated the correlations between these two factors and their prognostic relevance in terms of biochemical (prostate-specific antigen, PSA) relapse after radical prostatectomy (RP) for localized PC. PATIENTS AND METHODS: The immunohistochemical expression of CD10 and NF-κB in samples from 70 patients who underwent RP for localized PC was correlated with the preoperative PSA level, Gleason score, pathological stage and time to PSA failure. RESULTS: CD10 expression was inversely associated with NF-κB expression (p < 0.001), stage (p = 0.03) and grade (p = 0.003), whereas NF-κB was directly related with stage (p = 0.006) and grade (p = 0.002). The median time to PSA failure was 56 months. CD10 and NF-κB were directly (p < 0.001) and inversely (p < 0.001) correlated with biochemical recurrence-free survival, respectively. CD10 expression (p = 0.022) and stage (p = 0.018) were independently associated with time to biochemical recurrence. CONCLUSION: Low CD10 expression is an adverse prognostic factor for biochemical relapse after RP in localized PC, which is also associated with high NF-κB expression. Decreased CD10 expression which would lead to increased neuropeptide signaling and NF-κB activity may be present in a subset of early PCs.

Bortezomib reverses the proliferative and antiapoptotic effect of neuropeptides on prostate cancer cells.

OBJECTIVES: Neuropeptides are important signal initiators in advanced prostate cancer, partially acting through activation of nuclear factor kappa B. Central to nuclear factor kappa B regulation is the ubiquitin-proteasome system, pharmacological inhibition of which has been proposed as an anticancer strategy. We investigated the putative role of the proteasome inhibitor bortezomib in neuropeptides signaling effects on prostate cancer cells. METHODS: Human prostate cancer cell lines, LNCaP and PC-3, were used to examine cell proliferation, levels of proapoptotic (caspase-3, Bad) and cell cycle regulatory proteins (p53, p27, p21), as well as total and phosphorylated Akt and p44/42 mitogen-activated protein kinase proteins. Furthermore, 20S proteasome activity, subcellular localization of nuclear factor kappa B and transcription of nuclear factor kappa B target genes, interleukin-8 and vascular endothelial growth factor, were assessed. RESULTS: Neuropeptides (endothelin-1, bombesin) increased cell proliferation, whereas bortezomib decreased proliferation and induced apoptosis, an effect maintained after cotreatment with neuropeptides. Bad, p53, p21 and p27 were downregulated by neuropeptides in PC-3, and these effects were reversed with the addition of bortezomib. Neuropeptides increased proteasomal activity and nuclear factor kappa B levels in PC-3, and these effects were prevented by bortezomib. Interleukin-8 and vascular endothelial growth factor transcripts were induced after neuropeptides treatment, but downregulated by bortezomib. These results coincided with the ability of bortezomib to reduce mitogen-activated protein kinase signaling in both cell lines. CONCLUSIONS: These findings are consistent with bortezomib-mediated abrogation of neuropeptides-induced proliferative and antiapoptotic signaling. Thus, the effect of the drug on the neuropeptides axis needs to be further investigated, as neuropeptide action in prostate cancer might entail involvement of the proteasome.

Inverse baseline expression pattern of the NEP/neuropeptides and NFκB/proteasome pathways in androgen-dependent and androgen-independent prostate cancer cells.

BACKGROUND: Castration-resistance in prostate cancer (PC) is a critical event hallmarking a switch to a more aggressive phenotype. Neuroendocrine differentiation and upregulation of NFκB transcriptional activity are two mechanisms that have been independently linked to this process. METHODS: We investigated these two pathways together using in vitro models of androgen-dependent (AD) and androgen-independent (AI) PC. We measured cellular levels, activity and surface expression of Neutral Endopeptidase (NEP), levels of secreted Endothelin-1 (ET-1), levels, sub-cellular localisation and DNA binding ability of NFκB, and proteasomal activity in human native PC cell lines (LnCaP and PC-3) modelling AD and AI states. RESULTS: At baseline, AD cells were found to have high NEP expression and activity and low secreted ET-1. In contrast, they exhibited a low-level activation of the NFκB pathway associated with comparatively low 20S proteasome activity. The AI cells showed the exact mirror image, namely increased proteasomal activity resulting in a canonical pathway-mediated NFκB activation, and minimal NEP activity with increased levels of secreted ET-1. CONCLUSIONS: Our results seem to support evidence for divergent patterns of expression of the NFκB/proteasome pathway with relation to components of the NEP/neuropeptide axis in PC cells of different level of androgen dependence. NEP and ET-1 are inversely and directly related to an activated state of the NFκB/proteasome pathway, respectively. A combination therapy targeting both pathways may ultimately prove to be of benefit in clinical practice.

Nonbacterial thrombotic (marantic) endocarditis in a patient with colorectal cancer.

BACKGROUND: Marantic endocarditis, presently termed nonbacterial thrombotic endocarditis (NBTE), is an infrequent post-mortem diagnosis in the adult population but a not so rare event in the course of neoplastic conditions. CASE REPORT: We describe the case of a 74-year-old woman with advanced sigmoid adenocarcinoma, who developed aseptic vegetations in the right atrium of the heart. Systemic anticoagulation therapy was started, and upon clinical improvement systemic chemotherapy was added, resulting in partial response to antineoplastic therapy along with improvement of her cardiopulmonary status. A new cardiac assessment upon tumor recurrence was unable to distinguish the previously described lesions but disclosed a small mitral valve vegetation, in the absence of any signs or symptoms. The patient was again treated with chemotherapy and remains asymptomatic with stable disease. CONCLUSIONS: Although a hypercoagulable state may be etiologically related to malignant conditions, a strong clinical suspicion of NBTE is required. In these cases, it is often difficult to establish a definite diagnosis; however, immediate anticoagulation treatment is mandatory for the prevention of de novo or further thromboembolic events.

The ubiquitin-proteasome system in cancer, a major player in DNA repair. Part 2: transcriptional regulation.

DNA repair is an indispensable part of a cell's defence system against the devastating effects of DNA-damaging conditions. The regulation of this function is a really demanding situation, particularly when the stressing factors persist for a long time. In such cases, the depletion of existing DNA repair proteins has to be compensated by the induction of the analogous gene products. In addition, the arrest of transcription, which is another result of many DNA-damaging agents, needs to be overcome through regulation of transcription-specific DNA repair pathways. The involvement of the ubiquitin-proteasome system (UPS) in cancer- and chemotherapy-related DNA-damage repair relevant to the above transcriptional modification mechanisms are illustrated in this review. Furthermore, the contribution of UPS to the regulation of localization and accessibility of DNA repair proteins to chromatin, in response to cellular stress is discussed.

The ubiquitin-proteasome system in cancer, a major player in DNA repair. Part 1: post-translational regulation.

DNA repair is a fundamental cellular function, indispensable for cell survival, especially in conditions of exposure to environmental or pharmacological effectors of DNA damage. The regulation of this function requires a flexible machinery to orchestrate the reversal of harmful DNA lesions by making use of existing proteins as well as inducible gene products. The accumulation of evidence for the involvement of ubiquitin-proteasome system (UPS) in DNA repair pathways, that is reviewed here, has expanded its role from a cellular waste disposal basket to a multi-dimensional regulatory system. This review is the first of two that attempt to illustrate the nature and interactions of all different DNA repair pathways where UPS is demonstrated to be involved, with special focus on cancer- and chemotherapy-related DNA-damage repair. In this first review, we will be presenting the proteolytic and non-proteolytic roles of UPS in the post-translational regulation of DNA repair proteins, while the second review will focus on the UPS-dependent transcriptional response of DNA repair after DNA damage and stress.

Prospective assessment of systemic therapy followed by surgical removal of metastases in selected patients with renal cell carcinoma.

OBJECTIVE: To prospectively establish objective selection criteria for metastasectomy in patients with metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS: Between 1991 and 1999, 38 patients with mRCC with responsive or stable disease after initial systemic therapy, and with potentially resectable disease, were enrolled. Patients had a metastasectomy with curative intent and received consolidative adjuvant systemic therapy. RESULTS: Of the patients enrolled, 79% had stable disease after initial systemic therapy and 21% had a partial or complete response. Most (84%) had metastasectomy of one organ site. There was surgically no evidence of disease (sNED) in 76%. Operative morbidity and mortality were acceptable and 90% of the patients received adjuvant systemic therapy. The median (95% confidence interval) survival was 4.7 (3.0-7.8) years, and the median time to progression was 1.8 (0.8-3.1) years. Eight of 38 patients (21%) remained free of disease by the end of the study. Significant predictors of outcome were lack of sNED after metastasectomy, and the presence of pulmonary metastases. The median overall survival for those who had sNED was 5.6 years, vs 1.4 years for those who did not (P < 0.001). CONCLUSIONS: Metastasectomy in patients with mRCC not progressing after systemic therapy is feasible, with acceptable morbidity. Predictive factors for long-term outcome include pulmonary metastases and sNED. Future work evaluating treatments that can convert patients into surgical candidates will increase the cure rate of patients with mRCC.

CT quantification of effects of thalidomide in patients with metastatic renal cell carcinoma.

OBJECTIVE: Our objective was to use functional CT to evaluate the effects of thalidomide in patients with metastatic renal cell carcinoma. SUBJECTS AND METHODS: Patients with proven metastatic renal cell carcinoma were examined prospectively with functional CT. Functional CT studies (cine mode, 4 x 5 mm) were performed through the tumor after i.v. administration of a bolus of contrast material before and every 12 weeks after treatment with thalidomide. Quantitative values for blood flow, blood volume, mean transit time, and permeability-surface area product were calculated with commercial software. The average difference in percentage change in functional CT parameters from pretreatment to 12 and 24 weeks after treatment and the median difference in percentage change in functional CT parameters between response groups were assessed. We also tested whether percentage changes in functional CT parameters 12 weeks after treatment correlated with time to progression of disease and size of the perfused lesion. RESULTS: Sixteen patients with a total of 23 tumors underwent at least one follow-up functional CT examination. Blood flow, blood volume, and permeability-surface area product decreased significantly 12 weeks (-18%, p = 0.0039; -15%, p = 0.0350; -24%, p = 0.0010) and 24 weeks (-28%, p = 0.017; -19%, p = 0.0300; -25%, p = 0.0031) after treatment with thalidomide. Time to progression correlated significantly with percentage change in blood flow (r = -0.34; p = 0.040) and permeability-surface area product (r = -0.36, p = 0.023) at 12 weeks. Responders had a significantly larger decrease in blood flow 12 weeks after treatment than did nonresponders (-29% vs -6%; p = 0.032). We also found a significant correlation between decrease in size of the perfused lesion and percentage decrease in blood flow 12 weeks after treatment (r = 0.50; p = 0.019). CONCLUSION: Changes in functional CT parameters 12 weeks after treatment may be useful for monitoring the effects of thalidomide and predicting treatment outcome among patients with metastatic renal cell carcinoma. Further study with a larger clinical trial is needed.

Phase II study of capecitabine single-agent therapy in patients with metastatic renal cell carcinoma.

Fluoropyrimidines are known to have modest activity in the treatment of metastatic renal cell carcinoma (RCC). Capecitabine is an orally administered prodrug that is converted to fluorouracil and is of potential use in the treatment of this disease. We conducted a Phase II clinical trial of capecitabine administered as a single agent to patients with metastatic RCC. The treatment consisted of 1250 mg/m(2) capecitabine orally, twice daily (2500 mg/m(2) per day) days 1-14, repeated every 21 days. There were 15 patients, including 13 men and 2 women, who underwent a total of 67 cycles (median 3.5; range 1-15). Nine patients had undergone prior systemic therapy consisting of interferon-alpha in 3, interleukin-2 in 1, interferon-alpha plus interleukin-2 in 4, and investigational therapy with bryostatin-1 in 1. There were 14 patients assessable for response (one withdrew), and no responses were seen. Median time to progression was 9 weeks (range 1-45). There were 3 patients (21%) who had stable disease for 18, 39, and 45 weeks. Hematologic toxicity was mild. Three patients had grade 3 or 4 gastrointestinal toxicity, and 3 required dose reductions. There were 2 early deaths, including 1 patient with pulmonary edema and 1 with hypotension. The study was terminated because there were no responses in the first 14 assessable patients, indicating that the response rate was likely to be less than 20%. We conclude that single-agent capecitabine has minimal activity for the treatment of metastatic RCC.

Thalidomide/estramustine/paclitaxel in metastatic androgen-independent prostate cancer.

BACKGROUND: This is a phase I/II trial of thalidomide with estramustine and paclitaxel in men with androgen-independent prostate cancer (AIPC) who underwent previous chemotherapy. PATIENTS AND METHODS: Men with progressive AIPC were treated with oral thalidomide (200 mg, 400 mg, or 600 mg daily), intravenous paclitaxel (100 mg/m2 over 3 hours on days 3 and 10), and oral estramustine (140 mg 3 times daily on days 1-5 and days 8-12) every 21 days. RESULTS: Phase I: first cycle dose-limiting toxicity occurred in 0 of 3 patients at 200 mg thalidomide daily, 0 of 3 at 400 mg daily, and 1 of 3 at 600 mg daily (the designated maximum tolerated dose). Phase II: twenty-nine of 38 evaluable patients (76%; 95% confidence interval, 67%-87%) experienced a 50% decrease in prostate-specific antigen level. Five of 18 patients (28%) with measurable disease exhibited an objective response. Nine of 14 patients (64%) with disease refractory to previous taxane therapy had 50% decreases in prostate-specific antigen level. Grade 3/4 adverse events included neutropenia (9 of 39 [23%]), fatigue (9 of 39 [23%]), dyspnea (8 of 39 [21%]), and thromboembolic events (7 of 39 [18%]). Cumulative dose-limiting toxicity rates were minimal (13%) with thalidomide at 200 mg daily. CONCLUSION: The profile of activity of thalidomide/paclitaxel/estramustine in taxane-refractory AIPC warrants further investigation.

Results of a phase II study with doxorubicin, etoposide, and cisplatin in patients with fully characterized small-cell carcinoma of the prostate.

PURPOSE: To determine the activity and toxicity of doxorubicin in combination with cisplatin and etoposide in patients with small-cell prostate carcinoma (SCPCa) and to characterize the clinicopathologic features of SCPCa. PATIENTS AND METHODS: Patients with SCPCa (pure or mixed), measurable disease, good organ function, and no prior treatment with doxorubicin, etoposide, or cisplatin were treated every 4 weeks with doxorubicin 50 mg/m(2) as a 24-hour intravenous (IV) infusion followed by etoposide 120 mg/m(2)/d and cisplatin 25 mg/m(2)/d IV on days 2 to 4. RESULTS: Thirty-eight patients (36 assessable for response) were treated for a median of four cycles. Twenty-nine (81%) of 36 patients had prior hormonal therapy. Study patients had visceral metastases, lytic bone disease, and relatively low serum prostate-specific antigen (PSA). We observed 22 partial responses (response rate, 61% in an intent-to-treat analysis); toxicity was severe (grade 3 or 4 neutropenia 100%, thrombocytopenia 66%, mucositis 21%, and infection 68%). Three patients died of toxicity. Median time to progression and overall survival time were 5.8 months and 10.5 months, respectively. Performance status, serum albumin, and number of organs involved (but not PSA, carcinoembryonic antigen, or neuroendocrine markers) were predictors of survival. CONCLUSION: SCPCa presents unique clinicopathologic features. Addition of doxorubicin to the etoposide/cisplatin regimen caused higher toxicity in this patient population and failed to improve outcome. Given these results, we do not recommend further development of this regimen for patients with SCPCa. Improvement in therapy will come from understanding the biology of SCPCa progression and integrating new targeted therapies into the treatment of SCPCa.

Cisplatin, gemcitabine, and ifosfamide as weekly therapy: a feasibility and phase II study of salvage treatment for advanced transitional-cell carcinoma.

PURPOSE: We investigated the feasibility, safety, and antitumor activity of weekly gemcitabine given in combination with low doses of cisplatin and ifosfamide in previously treated patients with advanced transitional-cell carcinoma (TCC) of the urothelium. PATIENTS AND METHODS: Patients with measurable, metastatic or unresectable TCC who had received one or two prior chemotherapy regimens were eligible. On a 28-day course, doses of cisplatin 30 mg/m(2), gemcitabine 800 mg/m(2), and ifosfamide 1 g/m(2) were given on day 1 and then repeated on day 8 and day 15 unless there was dose-limiting hematologic toxicity. RESULTS: Fifty-one patients were registered; 10 patients participated in a pilot study, after which 41 patients were registered onto the phase II protocol. Forty-eight patients (94.1%) had dose-limiting hematologic toxicity on day 8 or day 15. Nonhematologic toxicity of grade 3 or greater consisted mainly of nausea and vomiting (seven patients, 13.7%) and infection (seven patients, 13.7%). Responses could be assessed in 49 of 51 eligible patients; two complete responses (4.1%) and 18 partial responses (36.7%) were observed for an overall response rate of 40.8% (exact 95% confidence interval, 27% to 56%). CONCLUSION: This regimen of cisplatin, gemcitabine, and ifosfamide is not feasible for weekly administration because of hematologic toxicity. Nevertheless, there was promising activity with only two doses per 28-day cycle. On the basis of these results, we have initiated a phase II trial of this combination given as a single dose every 14 days in patients with untreated, metastatic urothelial carcinoma.

Effect of endothelin-A receptor blockade with atrasentan on tumor progression in men with hormone-refractory prostate cancer: a randomized, phase II, placebo-controlled trial.

PURPOSE: To evaluate the efficacy and safety of atrasentan (ABT-627), an endothelin-A receptor antagonist, in the treatment of asymptomatic, hormone-refractory prostatic adenocarcinoma. PATIENTS AND METHODS: A double-blind, randomized, placebo-controlled clinical trial of hormone-refractory prostate cancer (HRPCa) patients was conducted in the United States and Europe. Two hundred eighty-eight asymptomatic patients with HRPCa and evidence of metastatic disease were randomly assigned to one of three study groups receiving a once-daily oral dose of placebo, 2.5 mg atrasentan, or 10 mg atrasentan, respectively. Primary end point was time to progression; secondary end points included time to prostate-specific antigen (PSA) progression, bone scan changes, and changes in bone and tumor markers. RESULTS: The three treatment groups were similar in all baseline characteristics. Median time to progression in intent-to-treat (ITT) patients (n = 288) was longer in the 10-mg atrasentan group compared with the placebo group: 183 v 137 days, respectively; (P =.13). Median time to progression in evaluable patients (n = 244) was significantly prolonged, from 129 days (placebo group) to 196 days (10-mg atrasentan group; P =.021). For both ITT and evaluable populations in the 10-mg atrasentan group, median time to PSA progression was twice that of the placebo group (155 v 71 days; P =.002). Patients who received placebo continued to have significant increases from baseline in serum (lactate dehydrogenase [LDH]), a marker of disease burden; elevations in LDH were uniformly attenuated by atrasentan in the ITT population. Headache, peripheral edema, and rhinitis were primary side effects, typically of mild to moderate severity. Quality of life was not adversely affected by atrasentan. CONCLUSION: Atrasentan is an oral, targeted therapy with favorable tolerability and the potential to delay progression of HRPCa.

Phase I trial of the proteasome inhibitor bortezomib in patients with advanced solid tumors with observations in androgen-independent prostate cancer.

PURPOSE: To determine the dose-limiting toxicity and maximum-tolerated dose of the proteasome inhibitor bortezomib administered intravenously weekly for 4 every 5 weeks; to determine the bortezomib pharmacokinetics and pharmacodynamics using plasma levels and an assay for 20S proteasome inhibition (PI) in whole blood; to correlate toxicity with bortezomib dose and degree of 20S PI; and to conduct a preliminary determination of the antitumor activity of bortezomib in patients with androgen independent prostate cancer (AIPCa). PATIENTS AND METHODS: Fifty-three patients (48 with AIPCa) received 128 cycles of bortezomib in doses ranging from 0.13 to 2.0 mg/m(2)/dose, utilizing a careful escalation scheme with a continuous reassessment method. Pharmacokinetic and pharmacodynamic studies were performed in 24 patients (at 1.45 to 2.0 mg/m(2)). RESULTS: A dose-related 20S PI was seen, with dose-limiting toxicity at 2.0 mg/m(2) (diarrhea, hypotension) occurring at an average 1-hour post-dose of >/= 75% 20S PI. Other side effects were fatigue, hypertension, constipation, nausea, and vomiting. No relationship was seen between body-surface area and bortezomib clearance over the narrow dose range tested. There was evidence of biologic activity (decline in serum prostate-specific antigen and interleukin-6 levels) at >/= 50% 20S PI. Two patients with AIPCa had prostate-specific antigen response and two patients had partial response in lymph nodes. CONCLUSION: The maximum-tolerated dose and recommended phase II dose of bortezomib in this schedule is 1.6 mg/m(2). Biologic activity (inhibition of nuclear factor-kappa B-related markers) and antitumor activity is seen in AIPCa at tolerated doses of bortezomib. This agent should be further explored with chemotherapy agents in advanced prostate cancer.

Prostate cancer cells-osteoblast interaction shifts expression of growth/survival-related genes in prostate cancer and reduces expression of osteoprotegerin in osteoblasts.

PURPOSE: Prostate cancer specifically metastasizes to bone where it leads to bone formation. We previously reported that coculturing MDA PCa 2b prostate cancer cells with primary mouse osteoblasts (PMOs) induced PMO proliferation and differentiation. An osteoblastic reaction was also observed in vivo after injection of MDA PCa 2b cells into the bones of severe combined immunodeficient disease mice. The aim of this study was to identify the sequence of events that leads to these osteoblastic lesions in vivo and, using this in vitro model, to define the contributions of various genes and cellular pathways in the pathophysiology of osteoblastic bone metastases of prostate cancer. EXPERIMENTAL DESIGN AND RESULTS: We show histological evidence of de novo bone formation as early as 2 weeks after injection of MDA PCa 2b cells in the bone of severe combined immunodeficient disease mice. In vitro, we show that PMOs induce MDA PCa 2b proliferation, suggesting a synergistic paracrine loop between these cells and PMOs. Endothelin (ET)-1, which is a mitogen for several cell types, is produced by all prostate cancer cell lines tested, and Atrasentan, an antagonist of ET-1 receptor A, partially reversed PMO proliferation induced by MDA PCa 2b cells. ET-1 is known to be comitogenic with a number of growth factors, including insulin-like growth factor (IGF)-I. In this study, we report that IGF-binding protein (IGFBP)-3 transcripts (that regulate levels of free IGF) are down-regulated in prostate cancer cells cocultured with PMO, whereas prostate-specific antigen (a protease known to cleave IGFBP-3) is detected in the 150-400 ng/ml range. Accordingly, IGFBP-3 has antiproliferative effects in PMOs, which were attenuated in our in vitro system. Taken together, our studies also implicate the IGF axis to play a role in this model of bone metastases. Secondly, the transcript level of mouse double minute 2 (a protein that regulate p53) was increased in prostate cancer cells grown with PMOs. The p53-dependent and -independent oncogenic activities of mouse double minute 2 suggest that osteoblasts induce a survival advantage in prostate cancer cells. Lastly, we show that expression of osteoprotegerin is decreased and of receptor activator of nuclear factor-kappaB ligand is increased in PMOs cultured in the presence of MDA PCa 2b cells, two events associated with osteoclast activation and bone resorption. CONCLUSIONS: Our results provide evidence that multiple and distinct molecular events affecting both bone formation and bone resorption concur to the increase bone mass in prostate cancer bone metastases. These data also provide a rationale for developing therapeutic strategies designed to target these molecular changes.

Treatment of refractory urothelial carcinoma with alternating paclitaxel, methotrexate, cisplatin (TMP) and 5-fluorouracil, alpha-interferon, cisplatin (FAP).

We assessed the activity and safety of a biochemotherapy regimen in which courses of paclitaxel, methotrexate, and cisplatin were alternated with courses of 5-fluorouracil, alpha-interferon, and cisplatin in the treatment of refractory urothelial carcinoma. Forty patients were enrolled in the study. In the phase I portion, 15 patients were treated according to an escalating dosage regimen designed to determine the maximum tolerated dose. A total of 30 patients received treatment according to the maximum tolerated dose regimen: methotrexate (30 mg/m(2)) given iv on days 1 and 22; paclitaxel (175 mg/m(2)) given iv over 3 h on day 1; cisplatin (70 and 25 mg/m(2)) administered iv on days 1 and 22, respectively; 5-fluorouracil (400 mg/m(2)) given iv by continuous infusion daily for 5 days beginning on day 22; and alpha-interferon (4 mIU/m(2)) given SC daily for 5 days simultaneously with the 5-fluorouracil infusions. The regimen was repeated at 42-day intervals. The 40 treated patients had an overall response rate of 43%, a complete response rate of 18%, and a median survival time of 44 weeks. Most of the toxic effects were hematologic: Grade 4 neutropenia occurred in 30% of patients (12 patients) and Grade 3 thrombocytopenia in 20% (8 patients). Even though this alternating biochemotherapy regimen was active for patients with refractory urothelial carcinoma, its activity was not better than that of certain single cytotoxic agents. Furthermore, the complicated dosing schedule and toxic effects of the regimen precluded its routine use in the treatment of urothelial carcinoma.