Gurkamal S. Chatta

Double-Blinded Randomized Study of High-Dose Calcitriol Plus Docetaxel Compared With Placebo Plus Docetaxel in Androgen-Independent Prostate Cancer: A Report From the ASCENT Investigators

PURPOSE To compare the safety and activity of DN-101, a new high-dose oral formulation of calcitriol designed for cancer therapy, and docetaxel with placebo and docetaxel. PATIENTS AND METHODS Patients with progressive metastatic androgen-independent prostate cancer and adequate organ function received weekly docetaxel 36 mg/m2 intravenously for 3 weeks of a 4-week cycle combined with either 45 microg DN-101 or placebo taken orally 1 day before docetaxel. The primary end point was prostate-specific antigen (PSA) response within 6 months of enrollment, defined as a 50% reduction confirmed at least 4 weeks later. RESULTS Two hundred fifty patients were randomly assigned. Baseline characteristics were similar in both arms. Within 6 months, PSA responses were seen in 58% in DN-101 patients and 49% in placebo patients (P = .16). Overall, PSA response rates were 63% (DN-101) and 52% (placebo), P = .07. Patients in the DN-101 group had a hazard ratio for death of 0.67 (P = .04) in a multivariate analysis that included baseline hemoglobin and performance status. Median survival has not been reached for the DN-101 arm and is estimated to be 24.5 months using the hazard ratio, compared with 16.4 months for placebo. Grade 3/4 adverse events occurred in 58% of DN-101 patients and in 70% of placebo-treated patients (P = .07). Most common grade 3/4 toxicities for DN-101 versus placebo were neutropenia (10% v 8%), fatigue (8% v 16%), infection (8% v 13%), and hyperglycemia (6% v 12%). CONCLUSION This study suggests that DN-101 treatment was associated with improved survival, but this will require confirmation because survival was not a primary end point. The addition of weekly DN-101 did not increase the toxicity of weekly docetaxel.

Trastuzumab, Paclitaxel, Carboplatin, and Gemcitabine in Advanced Human Epidermal Growth Factor Receptor-2/neu–Positive Urothelial Carcinoma: Results of a Multicenter Phase II National Cancer Institute Trial

PURPOSE We investigated the safety and efficacy (response rates, time to disease progression, survival) of trastuzumab, carboplatin, gemcitabine, and paclitaxel in advanced urothelial carcinoma patients and prospectively evaluated human epidermal growth factor receptor-2 (Her-2/neu) overexpression rates. PATIENTS AND METHODS Advanced urothelial carcinoma patients were screened for Her-2/neu overexpression. Eligibility for therapy required human epidermal growth factor receptor-2 (Her-2/neu) overexpression by immunohistochemistry (IHC), gene amplification and/or elevated serum Her-2/neu, no prior chemotherapy for metastasis, and adequate organ function including a normal cardiac function. Treatment consisted of trastuzumab (T) 4 mg/kg loading dose followed by 2 mg/kg on days 1, 8, and 15; paclitaxel (P) 200 mg/m2 on day 1; carboplatin (C; area under the curve, 5) on day 1; and gemcitabine (G) 800 mg/m2 on days 1 and 8. The primary end point was cardiac toxicity. RESULTS Fifty-seven (52.3%) of 109 registered patients were Her-2/neu positive, and 48.6% were positive by IHC. Her-2/neu-positive patients had more metastatic sites and visceral metastasis than did Her-2/neu negative patients. Forty-four of 57 Her-2/neu-positive patients were treated with TPCG. The median number of cycles was six (range, 1 to 12 cycles). The most common grade 3/4 toxicity was myelosuppression. Grade 3 sensory neuropathy occurred in 14% of patients, and 22.7% experienced grade 1 to 3 cardiac toxicity (grade 3, n = 2: one left ventricular dysfunction, one tachycardia). There were three [corrected] therapy-related deaths. Thirty-one (70%) of 44 patients responded (five complete and 26 partial), and 25 (57%) of 44 were confirmed responses. Median time to progression and survival were 9.3 and 14.1 months, respectively. CONCLUSION We prospectively characterized Her-2/neu status in advanced urothelial carcinoma patients. TPCG is feasible; cardiac toxicity rates were higher than projected, but the majority were grade two or lower. Determining the true contribution of trastuzumab requires a randomized trial.

Loss of New Chemokine CXCL14 in Tumor Tissue Is Associated with Low Infiltration by Dendritic Cells (DC), while Restoration of Human CXCL14 Expression in Tumor Cells Causes Attraction of DC Both In Vitro and In Vivo

Breast and kidney-expressed chemokine (BRAK) CXCL14 is a new CXC chemokine with unknown function and receptor selectivity. The majority of head and neck squamous cell carcinoma (HNSCC) and some cervical squamous cell carcinoma do not express CXCL14 mRNA, as opposed to constitutive expression by normal oral squamous epithelium. In this study, we demonstrate that the loss of CXCL14 in HNSCC cells and at HNSCC primary tumor sites was correlated with low or no attraction of dendritic cell (DC) in vitro, and decreased infiltration of HNSCC mass by DC at the tumor site in vivo. Next, we found that recombinant human CXCL14 and CXCL14-positive HNSCC cell lines induced DC attraction in vitro, whereas CXCL14-negative HNSCC cells did not chemoattract DC. Transduction of CXCL14-negative HNSCC cell lines with the human CXCL14 gene resulted in stimulation of DC attraction in vitro and increased tumor infiltration by DC in vivo in chimeric animal models. Furthermore, evaluating the biologic effect of CXCL14 on DC, we demonstrated that the addition of recombinant human CXCL14 to DC cultures resulted in up-regulation of the expression of DC maturation markers, as well as enhanced proliferation of allogeneic T cells in MLR. Activation of DC with recombinant human CXCL14 was accompanied by up-regulation of NF-κB activity. These data suggest that CXCL14 is a potent chemoattractant and activator of DC and might be involved in DC homing in vivo.

Intratumoral cytokines/chemokines/growth factors and tumor infiltrating dendritic cells: friends or enemies?

The tumor microenvironment consists of a variable combination of tumor cells, stromal fibroblasts, endothelial cells and infiltrating leukocytes, such as macrophages, T lymphocytes, and dendritic cells. A variety of cytokines, chemokines and growth factors are produced in the local tumor environment by different cells accounting for a complex cell interaction and regulation of differentiation, activation, function and survival of multiple cell types. The interaction between cytokines, chemokines, growth factors and their receptors forms a comprehensive network at the tumor site, which is primary responsible for overall tumor progression and spreading or induction of antitumor immune responses and tumor rejection. Although the general thought is that dendritic cells are among the first cells migrating to the tumor site and recognizing tumor cells for the induction of specific antitumor immunity, the clinical relevance of dendritic cells at the site of the tumor remains a matter of debate regarding their role in the generation of successful antitumor immune responses in human cancers. While several lines of evidence suggest that intratumoral dendritic cells play an important role in antitumor immune responses, understanding the mechanisms of dendritic cell/tumor cell interaction and modulation of activity and function of different dendritic cell subtypes at the tumor site is incomplete. This review is limited to discussing the role of intratumoral cytokine network in the understanding immunobiology of tumor-associated dendritic cells, which seems to possess different regulatory functions at the tumor site.

Intermittent chemotherapy in patients with metastatic androgen-independent prostate cancer: results from ASCENT, a double-blinded, randomized comparison of high-dose calcitriol plus docetaxel with placebo plus docetaxel.

Survival in patients with metastatic, chemotherapy‐naive, androgen‐independent prostate cancer (AIPC) is improved with 10 to 12 cycles of docetaxel‐containing chemotherapy but further management is undefined. In the current study, the authors examined retreatment with the same regimen after a treatment holiday.

The AKT inhibitor perifosine in biochemically recurrent prostate cancer: a phase II California/Pittsburgh cancer consortium trial.

BACKGROUND Perifosine is an oral alkylphospholipid that inhibits cancer cell growth through decreased Akt phosphorylation. We conducted a phase II trial of perifosine in patients with biochemically recurrent, hormone-sensitive prostate cancer. PATIENTS AND METHODS Eligible patients had histologically confirmed prostate cancer, previous prostatectomy and/or radiation therapy, and rising prostate-specific antigen (PSA) without radiographic evidence of metastasis. Previous androgen deprivation therapy < 9 months in duration (completed >or= 1 year before registration) was allowed. The primary endpoint was PSA response, defined as a decrease by >or= 50% from the pretreatment value. Treatment was composed of a loading dose of perifosine 900 mg orally on day 1, then 100 mg daily starting 24 hours later. RESULTS Of 25 patients, 24 were evaluable for response. After a median follow-up of 8 months, 5 patients (20%) had a reduction in serum PSA levels, but none met criteria for PSA response. Three patients immediately progressed with no response to therapy. Median progression-free survival was 6.64 months (range, 4.53-12.81 months). No change in the PSA doubling time (7 months) was observed before and after treatment initiation. Dose-limiting toxicities (all grade 3) included hyponatremia, arthritis, hyperuricemia, and photophobia. CONCLUSION Although well tolerated, perifosine did not meet prespecified PSA criteria for response as a single agent in biochemically recurrent prostate cancer. However, 20% of patients had evidence of PSA reduction, suggesting modest single-agent clinical activity. The role of perifosine in combination with androgen deprivation or chemotherapy is currently under investigation.

A phase II trial of the Src-kinase inhibitor AZD0530 in patients with advanced castration-resistant prostate cancer: A California Cancer Consortium study

Prostate cancer cells undergo neuroendocrine differentiation during androgen deprivation and secrete neuropeptides, hence activating androgen receptor-regulated genes. Src-family protein kinases are involved in neuropeptide-induced prostate cancer growth and migration. A phase II trial of AZD0530, an oral Src-family kinase inhibitor, in patients with advanced castration resistant prostate cancer was conducted. The primary endpoint was prostate cancer-specific antigen (PSA) response rate, defined as a 30% or greater decrease. A two-stage Simon design was used. Eligibility criteria included documentation of castration resistance (including antiandrogen withdrawal), adequate end-organ function, and performance status, and not more than one prior taxane-based chemotherapy regimen. AZD0530 was given at 175 mg orally once daily continuously. Rapid accrual led to 28 patients registering in the first stage. Median age was 67 years. Sixteen patients had performance status (PS) 0, eight patients had PS 1, and four patients had PS 2. Nine patients (32%) had prior docetaxel-based chemotherapy. Five patients had transient PSA reductions not meeting PSA response criteria. Median progression-free survival time was 8 weeks. Treatment was generally well tolerated. AZD0530, a potent oral Src kinase inhibitor, is feasible and tolerable in this pretreated patient population but possessed little clinical efficacy as monotherapy. Strong preclinical evidence warrants further investigation of AZD0530 in earlier-stage prostate cancer or as combination therapy.

Phase I and Pharmacodynamic Study of 17-(Allylamino)-17-Demethoxygeldanamycin in Adult Patients with Refractory Advanced Cancers

Purpose: The primary objective was to establish the dose-limiting toxicity (DLT) and recommended phase II dose of 17-(allylamino)-17-demethoxygeldanamycin (17AAG) given twice a week. Experimental Design: Escalating doses of 17AAG were given i.v. to cohorts of three to six patients. Dose levels for schedule A (twice weekly × 3 weeks, every 4 weeks) were 100, 125, 150, 175, and 200 mg/m2 and for schedule B (twice weekly × 2 weeks, every 3 weeks) were 150, 200, and 250 mg/m2. Peripheral blood mononuclear cells (PBMC) were collected for assessment of heat shock protein (HSP) 90 and HSP90 client proteins. Results: Forty-four patients were enrolled, 32 on schedule A and 12 on schedule B. On schedule A at 200 mg/m2, DLTs were seen in two of six patients (one grade 3 thrombocytopenia and one grade 3 abdominal pain). On schedule B, both patients treated at 250 mg/m2 developed DLT (grade 3 headache with nausea/vomiting). Grade 3/4 toxicities seen in >5% of patients were reversible elevations of liver enzymes (47%), nausea (9%), vomiting (9%), and headache (5%). No objective tumor responses were observed. The only consistent change in PBMC proteins monitored was a 0.8- to 30-fold increase in HSP70 concentrations, but these were not dose dependent. The increase in PBMC HSP70 persisted throughout the entire cycle of treatment but returned to baseline between last 17AAG dose of cycle 1 and first 17AAG dose of cycle 2. Conclusions: The recommended phase II doses of 17AAG are 175 to 200 mg/m2 when given twice a week and consistently cause elevations in PBMC HSP70.

Phase II Study of Aflibercept (VEGF-Trap) in Patients With Recurrent or Metastatic Urothelial Cancer, a California Cancer Consortium Trial

OBJECTIVES To determine whether aflibercept, a recombinant fusion protein that binds and neutralizes multiple vascular endothelial growth factor isoforms, is effective in the treatment of urothelial cancer. The efficacy of systemic therapies for advanced urothelial cancer after failure of front-line platinum-based chemotherapy is limited. Evidence has shown that vascular endothelial growth factor is important in the pathophysiology of urothelial cancer. METHODS Patients with measurable, metastatic, or locally advanced urothelial cancer previously treated with 1 platinum-containing regimen were enrolled. Aflibercept was administered at 4 mg/kg intravenously every 2 weeks. The response rate (RR) and progression-free survival (PFS) were assessed in a 2-stage accrual design (22 + 18). A maximum of 40 patients were to be accrued to rule out a null hypothesis RR of 4% and PFS of 3 months versus an alternative RR of 15% and PFS of 5.4 months, with α = 0.12 and β = 0.19. RESULTS A total of 22 patients were accrued. One partial response (4.5% RR, 95% confidence interval 0.1%-22.8%) was seen. The median PFS was 2.79 months (95% confidence interval 1.74-3.88). Attributable Grade 3 toxicities included fatigue, hypertension, proteinuria, pulmonary hemorrhage, pain, hyponatremia, anorexia, and lymphopenia. No treatment-related Grade 4 or greater toxicities occurred. CONCLUSIONS Aflibercept was well tolerated, with toxicity similar to those seen with other vascular endothelial growth factor pathway inhibitors; however, it had limited single-agent activity in patients with urothelial carcinoma previously treated with platinum-containing chemotherapy.

Restoration by IL-15 of MHC Class I Antigen-Processing Machinery in Human Dendritic Cells Inhibited by Tumor-Derived Gangliosides

We have recently reported that MHC class I Ag-processing machinery (APM) component expression in dendritic cells (DC) might be down-regulated by tumor cells. However, the tumor-derived factors responsible for inhibition of the APM component expression in DC generated in the tumor microenvironment as well as potential protective mechanism have not yet been investigated. In this article, we demonstrate that expression of several MHC class I APM components, including MB1 (β5), LMP2, LMP7, LMP10, and ERp57, is significantly down-regulated in human DC generated in the presence of primary oral squamous cell carcinoma cell lines or coincubated with purified gangliosides. Suppression of MHC class I APM component expression in DC generated in the presence of tumor cells was significantly attenuated by the inhibition of glucosyl transferase in tumor cells, suggesting that tumor-induced MHC class I APM component down-regulation in DC was mediated in part by oral squamous cell carcinoma-derived gangliosides. Furthermore, rIL-15 restored both tumor cell-induced and ganglioside-induced MHC class I APM component expression in DC, as well as their ability to present Ags to autologous Ag-specific T cells. These results demonstrate that IL-15 restores MHC class I APM component expression in DC down-regulated by tumor-derived gangliosides.