First-in-Human Phase 1b Trial of Quinacrine Plus Capecitabine in Patients With Refractory Metastatic Colorectal Cancer

BACKGROUND

Quinacrine plus a fluoropyrimidine has in vivo efficacy against metastatic colorectal cancer (mCRC). This phase 1b trial evaluated the combination of quinacrine plus capecitabine in patients with treatment-refractory mCRC.

PATIENTS AND METHODS

Using a modified Simon accelerated titration design, adults with treatment-refractory mCRC were treated with capecitabine 1000 mg/m² twice daily for 14/21-day cycle, and escalating doses of quinacrine 100 mg daily, 100 mg twice daily, and 200 mg twice daily for 21 days. The primary endpoint was identifying the maximum tolerated dose, determining tolerability and safety. In an expansion cohort, it was overall response rate and time to tumor progression (TTP).

RESULTS

Ten patients (median age of 60 years) were treated in phase 1b. The first 2 quinacrine dosing levels were well tolerated. Dose-limiting toxicities were seen in 3 patients treated with quinacrine 200 mg twice daily. Five additional patients tolerated quinacrine 100 mg twice daily without further dose-limiting toxicities, thus establishing the maximum tolerated dose. Seven additional expansion-cohort patients enrolled onto the study before quinacrine manufacturing ceased within the United States. Five patients experienced stable disease, 1 partial response, and 10 disease progression. Median TTP overall was 2.12 months and median overall survival 5.22 months for the 17 patients.

CONCLUSION

Capecitabine and quinacrine can be safely administered at the maximum tolerated dose of capecitabine 1000 mg/m² by mouth twice daily on days 1-14 and quinacrine 100 mg by mouth twice daily on days 1-21 of a 21-day cycle in mCRC patients. Although the expansion study was halted early, TTP was in line with other studies of refractory mCRC, suggesting activity of this regimen in heavily pretreated patients.

A phase ib trial to evaluate the safety and efficacy of quinacrine plus capecitabine in patients with refractory metastatic colorectal cancer

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Background: Acridines emerged from a cell-based screen for p53-pathway restoring compounds. Quinacrine, an acridine demonstrating p53 pathway restoration properties, displayed preclinical anti-tumor effects when used as monotherapy in colorectal cancer (CRC) cell culture and in vivo xenografts. Quinacrine suppresses survival pathways by inhibiting Mcl-1 expression, NFkB, STAT3, and angiogenesis. The combination of quinacrine plus 5-FU showed in-vivo preclinical efficacy against CRC with mutant KRAS, BRAF, or p53. Capecitabine, an oral 5-FU prodrug, is FDA-approved to treat metastatic (m)CRC. This phase I trial evaluated the safety and efficacy of quinacrine plus capecitabine in patients with refractory mCRC. Methods: Patients ≥18 years old with histologically confirmed mCRC refractory to standard therapy or with no standard therapy options available were eligible for the study. Using a modified 4B Simon’s accelerated titration design, patients were treated with a fixed dose of capecitabine 1000 mg/m2 twice daily (bid) for 14 days of a 21-day cycle, and escalating doses of quinacrine 100 mg daily, 100 mg bid, and 200 mg bid for 21 days. The primary endpoint was to identify the maximum tolerated dose (MTD) of quinacrine in combination with capecitabine and to determine their tolerability and safety. Results: Ten patients were enrolled, median age 60-years old (range: 56-79). Quinacrine 100 mg daily and 100 mg bid were well tolerated by the first two patients. Dose Limiting Toxicities (DLTs) were seen in 3 patients treated with quinacrine 200 mg bid and included hyperbilirubinemia, transaminitis, increased alkaline phosphatase, hypokalemia, diarrhea, vomiting, and dehydration. No grade 4 or 5 toxicities were seen. 5 additional patients tolerated treatment with quinacrine 100 mg bid and capecitabine without further DLTs making this the MTD. The median time on treatment was 63 days. Three patients came off study prior to their first response evaluation. In 7 patients evaluable for response, 4 had stable disease (57%), while 3 (43%) had disease progression. Median overall survival was 196.5 days. Conclusions: Capecitabine and quinacrine can be safely administered at the MTD of capecitabine 1000 mg/m2 PO bid D1-14 and quinacrine 100 mg PO bid D1-21 of a 21-day cycle for patients with mCRC. A phase II study is ongoing. Clinical trial information: NCT01844076.

A Novel Cross-Disciplinary Multi-Institute Approach to Translational Cancer Research: Lessons Learned from Pennsylvania Cancer Alliance Bioinformatics Consortium (PCABC)

Background

The Pennsylvania Cancer Alliance Bioinformatics Consortium (PCABC, http://www.pcabc.upmc.edu ) is one of the first major project-based initiatives stemming from the Pennsylvania Cancer Alliance that was funded for four years by the Department of Health of the Commonwealth of Pennsylvania. The objective of this was to initiate a prototype biorepository and bioinformatics infrastructure with a robust data warehouse by developing a statewide data model (1) for bioinformatics and a repository of serum and tissue samples; (2) a data model for biomarker data storage; and (3) a public access website for disseminating research results and bioinformatics tools. The members of the Consortium cooperate closely, exploring the opportunity for sharing clinical, genomic and other bioinformatics data on patient samples in oncology, for the purpose of developing collaborative research programs across cancer research institutions in Pennsylvania. The Consortium's intention was to establish a virtual repository of many clinical specimens residing in various centers across the state, in order to make them available for research. One of our primary goals was to facilitate the identification of cancer-specific biomarkers and encourage collaborative research efforts among the participating centers.

Methods

The PCABC has developed unique partnerships so that every region of the state can effectively contribute and participate. It includes over 80 individuals from 14 organizations, and plans to expand to partners outside the State. This has created a network of researchers, clinicians, bioinformaticians, cancer registrars, program directors, and executives from academic and community health systems, as well as external corporate partners - all working together to accomplish a common mission. The various sub-committees have developed a common IRB protocol template, common data elements for standardizing data collections for three organ sites, intellectual property/tech transfer agreements, and material transfer agreements that have been approved by each of the member institutions. This was the foundational work that has led to the development of a centralized data warehouse that has met each of the institutions’ IRB/HIPAA standards.

Results

Currently, this “virtual biorepository” has over 58,000 annotated samples from 11,467 cancer patients available for research purposes. The clinical annotation of tissue samples is either done manually over the internet or semi-automated batch modes through mapping of local data elements with PCABC common data elements. The database currently holds information on 7188 cases (associated with 9278 specimens and 46,666 annotated blocks and blood samples) of prostate cancer, 2736 cases (associated with 3796 specimens and 9336 annotated blocks and blood samples) of breast cancer and 1543 cases (including 1334 specimens and 2671 annotated blocks and blood samples) of melanoma. These numbers continue to grow, and plans to integrate new tumor sites are in progress. Furthermore, the group has also developed a central web-based tool that allows investigators to share their translational (genomics/proteomics) experiment data on research evaluating potential biomarkers via a central location on the Consortium's web site.

Conclusions

The technological achievements and the statewide informatics infrastructure that have been established by the Consortium will enable robust and efficient studies of biomarkers and their relevance to the clinical course of cancer.

Immunotherapy for triple-negative breast cancer: Existing challenges and exciting prospects

Patients with breast tumors that do not express the estrogen receptor, the progesterone receptor, nor Her-2/neu are hence termed "triple negatives", and generally have a poor prognosis, with high rates of systemic recurrence and refractoriness to conventional therapy regardless of the choice of adjuvant treatment. Thus, more effective therapeutic options are sorely needed for triple-negative breast cancer (TNBC), which occurs in approximately 20% of diagnosed breast cancers. In recent years, exploiting intrinsic mechanisms of the host immune system to eradicate cancer cells has achieved impressive success, and the advances in immunotherapy have yielded potential new therapeutic strategies for the treatment of this devastating subtype of breast cancer. It is anticipated that the responses initiated by immunotherapeutic interventions will explicitly target and annihilate tumor cells, while at the same time spare normal cells. Various immunotherapeutic approaches have been already developed and tested, which include the blockade of immune checkpoints using neutralizing or blocking antibodies, induction of cytotoxic T lymphocytes (CTLs), adoptive cell transfer-based therapy, and modulation of the tumor microenvironment to enhance the activity of CTLs. One of the most important areas of breast cancer research today is understanding the immune features and profiles of TNBC and devising novel immune-modulatory strategies to tackling TNBC, a subtype of breast cancer notorious for its poor prognosis and its imperviousness to conventional treatments. On the optimal side, one can anticipate that novel, effective, and personalized immunotherapy for TNBC will soon achieve more success and impact clinical treatment of this disease which afflicts approximately 20% of patients with breast cancer. In the present review, we highlight the current progress and encouraging developments in cancer immunotherapy, with a goal to discuss the challenges and to provide future perspectives on how to exploit a variety of new immunotherapeutic approaches including checkpoint inhibitors and neoadjuvant immunotherapy for the treatment of patients with TNBC.

Efficacy of the PARP Inhibitor Veliparib with Carboplatin or as a Single Agent in Patients with Germline BRCA1- or BRCA2-Associated Metastatic Breast Cancer: California Cancer Consortium Trial NCT01149083

Purpose: We aimed to establish the MTD of the poly (ADP-ribose) (PAR) polymerase inhibitor, veliparib, in combination with carboplatin in germline BRCA1- and BRCA2- (BRCA)-associated metastatic breast cancer (MBC), to assess the efficacy of single-agent veliparib, and of the combination treatment after progression, and to correlate PAR levels with clinical outcome.Experimental Design: Phase I patients received carboplatin (AUC of 5-6, every 21 days), with escalating doses (50-20 mg) of oral twice-daily (BID) veliparib. In a companion phase II trial, patients received single-agent veliparib (400 mg BID), and upon progression, received the combination at MTD. Peripheral blood mononuclear cell PAR and serum veliparib levels were assessed and correlated with outcome.Results: Twenty-seven phase I trial patients were evaluable. Dose-limiting toxicities were nausea, dehydration, and thrombocytopenia [MTD: veliparib 150 mg po BID and carboplatin (AUC of 5)]. Response rate (RR) was 56%; 3 patients remain in complete response (CR) beyond 3 years. Progression-free survival (PFS) and overall survival (OS) were 8.7 and 18.8 months. The PFS and OS were 5.2 and 14.5 months in the 44 patients in the phase II trial, with a 14% RR in BRCA1 (n = 22) and 36% in BRCA2 (n = 22). One of 30 patients responded to the combination therapy after progression on veliparib. Higher baseline PAR was associated with clinical benefit.Conclusions: Safety and efficacy are encouraging with veliparib alone and in combination with carboplatin in BRCA-associated MBC. Lasting CRs were observed when the combination was administered first in the phase I trial. Further investigation of PAR level association with clinical outcomes is warranted. Clin Cancer Res; 23(15); 4066-76. ©2017 AACR.

Molecular profiling of 6,892 colorectal cancer samples suggests different possible treatment options specific to metastatic sites

Metastatic colorectal cancer (mCRC) carries a poor prognosis with an overall 5-year survival of 13.1%. Therapies guided by tumor profiling have suggested benefit in advanced cancer. We used a multiplatform molecular profiling (MP) approach to identify key molecular changes that may provide therapeutic options not typically considered in mCRC. We evaluated 6892 mCRC referred to Caris Life Sciences by MP including sequencing (Sanger/NGS), immunohistochemistry (IHC) and in-situ hybridization (ISH). mCRC metastases to liver, brain, ovary or lung (n = 1507) showed differential expression of markers including high protein expression of TOPO1 (52%) and/or low RRM1 (57%), TS (71%) and MGMT (39%), suggesting possible benefit from irinotecan, gemcitabine, 5FU/capecitabine and temozolomide, respectively. Lung metastases harbored a higher Her2 protein expression than the primary colon tumors (4% vs. 1.8%, p = 0.028). Brain and lung metastases had higher KRAS mutations than other sites (65% vs 59% vs 47%, respectively, p = 0.07, <0.01), suggesting poor response to anti-EGFR therapies. BRAF-mutated CRC (n = 455) showed coincident high protein expression of RRM1 (56%), TS (53%) and low PDGFR (22%) as compared with BRAF wild-type tumors. KRAS-mutated mCRC had higher protein expression of c-MET (47% vs. 36%) and lower MGMT (56% vs. 63%), suggesting consideration of c-MET inhibitors and temozolomide. KRAS-mutated CRC had high TUBB3 (42% vs. 33%) and low Her2 by IHC (0.5%) and HER2 by FISH (3%, p <0.05). CRC primaries had a lower incidence of PIK3CA and BRAF mutations in rectal cancer versus colon cancer (10% and 3.3%, respectively). MP of 6892 CRCs identified significant differences between primary and metastatic sites and among BRAF/KRAS sub-types. Our findings are hypothesis generating and need to be examined in prospective studies. Specific therapies may be considered for different actionable targets in mCRC as revealed by MP.

Primary female breast sarcoma: clinicopathological features, treatment and prognosis

Primary breast sarcoma (PBS) is a rare and heterogeneous group of malignancies with limited publications. We obtained data from the Surveillance, Epidemiology, and End Results Program and performed analysis to determine clinicopathological characteristics of PBS and estimate their associations with overall survival (OS) and cancer-specific survival (CSS). Median age of PBS was 55–59 years and median OS was 108 months. Age, overlap or entire breast involvement, tumor histology, and tumor spread were associated with poor survival outcomes. In the multivariable analysis, tumor size, lymph node involvement, distant metastasis and histologic grade were correlated with survival outcomes (P < 0.001). In M0 patients, mastectomy was associated with worse survival outcomes compared with breast conservative surgery (BCS) (adjusted hazard ratio [adjHR], 1.80; 95% CI, 1.31–2.47), regardless of tumor size, tumor grade, tumor histology or radiation history. Adjuvant radiation improved survival outcomes in patients with tumor size >5 cm (adjHR, 0.63; 95% CI, 0.43–0.91), but not in patients with tumor size ≤ 5 cm. Our study demonstrated clinicopathological characteristics of PBS in the US population and supports performing BCS if R0 resection can be achieved, with radiation if tumor size is over 5 cm.

Neoadjuvant Chemotherapy for Muscle-Invasive Bladder Cancer: A Systematic Review and Two-Step Meta-Analysis

BACKGROUND

Platinum-based neoadjuvant chemotherapy has been shown to improve survival outcomes in muscle-invasive bladder cancer patients. We performed a systematic review and meta-analysis to provide updated results of previous findings. We also summarized published data to compare clinical outcomes of methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) versus gemcitabine and cisplatin/carboplatin (GC) in the neoadjuvant setting.

METHODS

A meta-analysis of 15 randomized clinical trials was performed to compare neoadjuvant chemotherapy plus local treatment with the same local treatment alone. Because no randomized trials have investigated MVAC versus GC in the neoadjuvant setting, a meta-analysis of 13 retrospective studies was performed to compare MVAC with GC.

RESULTS

A total of 3,285 patients were included in 15 randomized clinical trials. There was a significant overall survival (OS) benefit associated with cisplatin-based neoadjuvant chemotherapy (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.79-0.96). A total of 1,766 patients were included in 13 retrospective studies. There was no significant difference in pathological complete response between MVAC and GC. However, GC was associated with a significantly reduced overall survival (HR, 1.26; 95% CI, 1.01-1.57). After excluding carboplatin data, GC still seemed to be inferior to MVAC in OS (HR, 1.31; 95% CI, 0.99-1.74), but the difference was no longer statistically significant.

CONCLUSION

These results support the use of cisplatin-based combination neoadjuvant chemotherapy in muscle-invasive bladder cancer. Although GC and MVAC had similar treatment response rates, the different survival outcome observed in this study requires further investigation.

IMPLICATIONS FOR PRACTICE

Platinum-based neoadjuvant chemotherapy (NCT) has been shown to improve survival outcomes in muscle-invasive bladder cancer (MIBC) patients, but the optimal neoadjuvant regimen has not been established. Methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) and gemcitabine and cisplatin/carboplatin (GC) are two of the most commonly used chemotherapy regimens in modern oncology. In this two-step meta-analysis, an updated and more precise estimate of the survival benefit of cisplatin-based NCT in MIBC is provided. This study also demonstrated that MVAC might have superior overall survival compared with GC (with or without carboplatin data) in the neoadjuvant setting. The findings suggest that NCT should be standard care in MIBC, and MVAC could be the preferred neoadjuvant regimen.

Endoscopic ultrasound-guided ethanol ablation of a large metastatic carcinoid tumor: success with a note of caution

Endoscopic ultrasonography with fine needle infusion (EUS-FNI) of alcohol is the most reported method for EUS-guided tumor ablation. Several studies have reported successful EUS-guided ablation of pancreatic neuroendocrine tumors. However, these tumors have been relatively small (< 3 cm). In this report, a 50-year-old man with a metastatic carcinoid tumor with a large porta hepatis mass was referred to our clinic for EUS-guided ethanol ablation. After two separate EUS-FNI ablations, there was a 36 % reduction in tumor size (9.0 × 11.4 cm to 6.7 × 9.8 cm) with associated tumor lysis syndrome. Chromogranin A levels decreased from 460 to 132 ng/mL. The patient reported complete resolution of abdominal pain within 2 weeks, but only mild improvement in flushing and diarrhea. In conclusion, large metastatic neuroendocrine tumors can be successfully treated with EUS-guided ethanol ablation. Evidence-based guidelines are needed with regard to the appropriate volume of ethanol injected in EUS-guided ablation to promote the efficacy and safety of this emerging procedure.

Personalized dosing via pharmacokinetic monitoring of 5-fluorouracil might reduce toxicity in early- or late-stage colorectal cancer patients treated with infusional 5-fluorouracil-based chemotherapy regimens

INTRODUCTION

Therapeutic plasma 5-fluorouracil (5-FU) levels are achieved in only 20% to 30% of patients with the current practice of administering 5-FU doses based on body surface area (BSA). Alternatively, 5-FU doses can be adjusted based on 5-FU pharmacokinetic (PK) monitoring. Although benefits of PK monitoring of 5-FU in metastatic colorectal cancer (CRC) have been reported, its utility among patients with early stage disease has not been reported.

PATIENTS AND METHODS

We retrospectively examined the effect of 5-FU PK monitoring in 84 CRC patients (49 stage IV and 35 stage II/III) receiving mFOLFOX6 (modifiedFOLFOX6; modified 5-fluorouracil, leucovorin, oxaliplatin protocol) or mFOLFIRI (modified 5-fluorouracil, leucovorin, irinotecan protocol). Forty-six of the 84 patients received 5-FU doses based on BSA and 38 received doses that were adjusted with PK monitoring. 5-FU plasma levels were measured using a nanoparticle immunoassay method.

RESULTS

5-fluorouracil PK monitoring significantly improved disease-free survival in stage II/III patients (P = .0429). There was also a trend towards improved progression-free survival among stage IV patients who had their 5-FU levels PK-monitored (P = .16). Moreover, 5-FU PK monitoring significantly reduced (P = .0437) and delayed (P = .0144) adverse effects in stage II/III patients. Toxicity occurred after the second 5-FU dose in the BSA group and after the sixth to seventh dose in the PK monitoring group. In stage IV patients, the onset of toxicities was also delayed with PK monitoring (P = .0605).

CONCLUSION

We provide evidence that PK monitoring of 5-FU is potentially beneficial for late stage and early stage CRC. These results contribute to the growing body of evidence regarding patient benefit when treatment decisions are based on the individual patient characteristics, in this case, a patients' 5-FU levels.

Predicting therapy response in live tumor cells isolated with the flexible micro spring array device

Cells disseminated from primary epithelial tumors into peripheral blood, called circulating tumor cells (CTCs), can be monitored to assess metastases and to provide a surrogate marker of treatment response. Here, we demonstrate how the flexible micro spring array (FMSA) device—a novel microfluidic device that enriches CTCs by two physical parameters: size and deformability—could be used in the rational development of treatment intervention and as a method to study the fundamental biology of CTCs. Cancer cells of different origins were spiked into healthy samples of donor blood to mimic blood samples of metastatic cancer patients. This spiked human blood was filtered using the FMSA device, and the recovered cells were successfully expanded in vitro and in a novel in vivo system. A series of experiments were performed to characterize these cells and to investigate the effect of chemotherapy on the resulting cultures. As few as 20 colon cancer cells in 7.5 mL blood could be isolated with the FMSA device, expanded both in vitro and in vivo and used at 25 cells per well to obtain significant and reliable chemosensitivity data. We also show that isolating a low number of viable patient CTCs and maintaining them in culture for a few weeks is possible. The isolation of viable cancer cells from human blood using the FMSA device provides a novel and realistic means for studying the biology of viable CTCs and for testing drug efficacy on these rare cells—a hypothesis that can be tested in future clinical trials.

Efficacy of the combination of ABT-888 (veliparib) and carboplatin in patients with BRCA-associated breast cancer

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Background: The combination of platinum agents and PARP inhibitors may benefit patients (pts) with BRCA-associated metastatic breast cancer (MBC). We report on the response and clinical benefit rates when combining the PARP inhibitor veliparib (V) and carboplatin (carb) in a phase I trial. Methods: BRCA carriers with MBC were eligible. Carb starting at an AUC of 6 was given IV in 21-day cycles (C) and V was given orally twice daily (BID) at dose levels (L) L1 through L5. Results: Twenty-eight pts (26 eligible) carrying BRCA1 (12) or BRCA2 (15), or both (1) mutations were accrued between June 2010 and June 2012. The median age (32-66) was 45 years. The number (#) of prior chemotherapy regimens given for MBC was 1 (0-5); 70% of BCs were ER+, and 7% were HER2+. The schema, dose limiting toxicities (DLT) during C 1, median # of Cs on trial, and maximum tolerated dose (MTD) are shown. There were 3 (12%) complete and 9 (35%) partial responses (PR). Unconfirmed PR or stable MBC (median duration: 8 months [6-10+]) were seen in 7 pts (27%); the clinical benefit rate was74%. The median progression-free survival (PFS) is 7.8 months (95% CI 7.3-9.5). The pt with Fallopian tube cancer had a CR. DLTs with C 1 were seen in 2/6 evaluable pts at L1 (1 pt w/grade 3 hyponatremia and dehydration, and 1pt w/grade 4 thrombocytopenia [PLT]), leading to de-escalation of carb. At L2, 1 pt had grade 4 PLT. At L5, 1 pt had grade 4 PLT, and 2 pts grade 3 PLT (1 pt also experienced grade 4 granulocytopenia [ANC]), defining the MTD at carb AUC 5 and V 150 mg BID (L4). Dose delays and/or dose adjustments due to grade ≥ 2 toxicities for ANC or PLT were seen during the first 3 Cs at L1 (100%), L2 (50 %), L3 (67%), L4 (83 %), and at L5 (67%). Conclusions: The combination of carb and V is active, and is associated with substantial clinical benefit rate and managable hematologic toxicities in BRCA carriers with MBC. Further definition of the role of V is warranted. [Table: see text]

Gastrointestinal stromal tumor (GIST) recurrence following surgery: review of the clinical utility of imatinib treatment

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. Surgery with complete removal of the tumor is the primary treatment for resectable GIST and the only chance of cure. However, recurrence after surgery is common. The 2 main prognostic factors are the mitotic activity and the size of the tumor. Tumor rupture is also a risk factor for postoperative recurrence, and extra care should be taken while manipulating this soft and friable tumor. Imatinib mesylate (IM, Gleevec(®), Novartis, Basel, Switzerland) is a tyrosine kinase inhibitor and was first studied in the palliative setting for metastatic GIST patients in the year 2000. It is now the cornerstone of metastatic GIST treatment. IM also plays an important role as an adjuvant treatment for resectable GIST and has been shown to increase the recurrence-free survival in phase III studies. However, some points remain to be clarified. Notably, the ideal duration of adjuvant IM after surgery is still unclear. It is also difficult to determine the exact place of surgery in metastatic or recurrent GIST patients in the IM era. A multidisciplinary approach is, therefore, mandatory to offer GIST patients the best treatment available.

Biology of bone metastases: causes and consequences

Breast cancer is a highly osteotropic neoplasm, and as many as 75% of patients with metastatic disease will have involvement of the bony skeleton. On radiologic examination, these metastases are predominantly osteolytic but can be osteoblastic or mixed. The mechanisms by which metastases are formed are complex, involving many steps that include angiogenesis, invasion, and proliferation in the bone microenvironment. Tumor cells in the bone microenvironment produce a large number of cytokines that stimulate osteoclastic activity. Increased osteoclastic activity, in turn, leads to production of a variety of lymphokines and growth factors that can increase tumor cell proliferation. Thus, a cytokine network is established, which results in an imbalance of the processes of bone formation and bone resorption. As tumor burden in bone increases, osteoclast-mediated bone resorption is accelerated, resulting in loss of bone strength, fractures, pain, and other morbidities. Tumor cells metastatic to bone can also secrete growth factors, leading to increased osteoblastic activity. Osteoblasts lay down an excess of new bone that is structurally weak. There is considerable crosstalk between osteoclasts, osteoblasts, macrophages, and other cellular elements within the bone environment. The increasing understanding of the biology of bone metastases has opened the door to improved management of this important clinical problem. Current treatment strategies include approaches to reduce tumor burden and developing treatments that directly inhibit osteoclast function. The bisphosphonates are a class of drugs that inhibit osteoclast recruitment and function. Several highly potent bisphosphonates are now available for clinical use and represent an important adjunct in the management of bone metastases from breast cancer, multiple myeloma, and several other types of malignancies. Some newer therapeutic approaches include agents designed to inhibit the osteoclast-osteoblast signaling interactions or alter processes of adhesion and invasion.

Toremifene: an evaluation of its safety profile

Toremifene has been in clinical use for 8 years for the treatment of advanced hormone-sensitive breast cancer and the adjuvant treatment of early breast cancer. More than 350,000 patient treatment years have accumulated, sufficient to allow evaluation of its longer-term safety profile in comparison with tamoxifen and, where possible, with raloxifene and aromatase inhibitors. We reviewed all preclinical and clinical safety data from 1978 to 2004 and comparative clinical safety data between October 1995 and the end of 2004. Secondary endometrial cancer incidence was lower with toremifene than with tamoxifen and was similar to that with raloxifene. It is speculated that toremifene may unmask existing endometrial tumors rather than induce new events. The risk of stroke, pulmonary embolism, and cataract may be lower with toremifene than with tamoxifen and the risk of pulmonary embolism and deep vein thrombosis lower than with raloxifene. Beneficial estrogen agonistic effects were equivalent to those of tamoxifen regarding bone mineral density and superior regarding lipid profiles.

Serum HER-2/neu conversion to positive at the time of disease progression in patients with breast carcinoma on hormone therapy

BACKGROUND

Prolonged exposure of breast carcinoma cells in vitro to tamoxifen results in tamoxifen resistance. Tamoxifen-resistant cells express increased HER-2/neu mRNA and protein. The objective of this study was to determine whether patients with metastatic or locally advanced breast carcinoma who have negative serum HER-2/neu status at the initiation of first-line hormone therapy with letrozole or tamoxifen convert to positive serum HER-2/neu status at the time of disease progression and to determine whether serum HER-2/neu conversion to positive status is associated with response to therapy and overall survival.

METHODS

Serum samples were obtained at baseline and at the time of disease progression from 240 patients who initially had negative serum HER-2/neu status (< 15 ng/mL). A manual microtiter, enzyme-linked immunosorbent assay that was specific for the extracellular domain of the HER-2/neu (c-erbB-2) oncoprotein product was used to quantitate serum levels.

RESULTS

Among 240 patients, 61 patients (26%) converted from serum HER-2/neu negative to positive (> 15 ng/mL) at the time of disease progression. Thirty-two of 129 patients (25%) who were treated with tamoxifen and 29 of 111 patients (26%) who were treated with letrozole became converted to positive serum HER-2/neu status at the time of disease progression. The response rate and the time to disease progression on first-line hormone therapy were not affected by serum HER-2/neu conversion. The survival of patients who converted to positive serum HER-2/neu status was significantly shorter compared with the survival of patients who remained negative for serum HER-2/neu. A multivariate analysis revealed that conversion to positive serum HER-2/neu status was an independent prognostic variable for survival.

CONCLUSIONS

Conversion to positive serum HER-2/neu status occurred in approximately 25% of patients who received first-line hormone therapy. Conversion to serum HER-2/neu-positive status occurred with equal frequency in antiestrogen and aromatase-inhibitor therapy. The current results showed that serum conversion to HER-2/neu-positive status was an independent risk factor for decreased survival in patients with breast carcinoma.

Optimizing bisphosphonate therapy in patients with breast cancer on endocrine therapy

Deterioration of bone health is a major concern during progression and treatment of patients with breast cancer, especially in postmenopausal women. Disease- and treatment-associated skeletal-related events include fractures, spinal compression, bone pain, and hypercalcemia of malignancy. Bisphosphonates, which inhibit osteoclastic bone resorption, are important new agents in the management of skeletal-related events, and their impact on breast cancer-related bone metastases and on bone loss during long-term estrogen deprivation therapies such as aromatase inhibitors is reviewed. Intravenous pamidronate has become the standard bisphosphonate to reduce or delay skeletal complications of advanced breast cancer bone metastases, but the more potent agent, zoledronic acid, appears to be at least as effective. Another agent, ibandronate, is also active but has not been investigated in comparison with the other intravenous bisphosphonates. Zoledronic acid is the most convenient to administer, requiring only a short infusion. The effects of bisphosphonates on bone health in women with early breast cancer are also being investigated. A single yearly infusion of zoledronic acid has been shown to significantly increase bone mineral density in osteoporotic postmenopausal women and to reduce biochemical markers of bone turnover. The possibility of such treatment-reversing aromatase inhibitor-associated bone loss during adjuvant therapy of breast cancer is being evaluated in a trial of letrozole, with zoledronic acid added initially or after the onset of bone loss or fracture.

Baseline serum NTx levels are prognostic in metastatic breast cancer patients with bone-only metastasis

BACKGROUND

There is significant heterogeneity in survival of patients with metastatic breast cancer who have bone-only metastasis. We studied the correlation of serum N-telopeptide (NTx), a marker of bone resorption, and its correlation with clinical outcomes in patients with metastatic breast cancer with bone-only or bone plus soft tissue metastasis.

PATIENTS AND METHODS

Serum was taken from 250 metastatic breast cancer patients with bone-only or bone plus soft tissue metastasis who participated in two similar randomized studies of second-line hormone therapy. An enzyme-linked immunosorbent assay specific for NTx of type I bone collagen was used to detect serum levels.

RESULTS

Sixty patients (24%) had elevated serum NTx levels, using the mean + 2 standard deviations (26 nanomoles Bone Collagen Equivalents per liter) of healthy women as a cut-off. The median duration of clinical benefit was significantly shorter in the group with elevated serum NTx levels compared with the group that had normal serum NTx levels (P=0.0004). Time to progression (TTP) was also significantly shorter in the patients with elevated serum NTx at 139 days compared with 220 days (P=0.0006). Median survival was also significantly shorter in patients with elevated baseline serum NTx levels at 663 days compared with 941 days (P<0.0001).

CONCLUSION

In this study, breast cancer patients with bone-only or bone plus soft tissue metastasis and elevated serum NTx levels have a shorter duration of clinical benefit, TTP and overall survival.

Treatment of advanced pancreatic cancer with opioid growth factor: phase I

Opioid growth factor (OGF) is an endogenous pentapeptide that inhibits growth of human pancreatic cancer cells in culture, as well as xenografts in nude mice. To establish the maximum tolerated dose (MTD), and determine safety and toxicity of OGF, a phase I trial was performed in patients with advanced unresectable pancreatic cancer. Patients with unresectable pancreatic adenocarcinoma were treated with escalating doses of OGF for 30 min i.v. to determine the MTD. The s.c. route of administration also was evaluated. Once the MTD was established, a group of patients was treated chronically, and monitored for safety and toxicity. Hypotension was the dose-limiting toxicity, resulting in a MTD of 250 microg/kg i.v. Due to limited solubility of OGF in small volumes, a maximum dose of 50 microg/kg twice daily was determined by the s.c. route of administration. No adverse events were reported for oxygen saturation, cardiac rhythm, laboratory values or neurological status in either the acute or chronic parts of the study with the i.v. or s.c. routes. During the chronic i.v. phase, two subjects had resolution of liver metastases and one showed regression of the pancreatic tumor. Mean survival from the time of diagnosis was 8.7 months (range 2-23 months) in the i.v. group and 9.5 months (range 1-18 months) in the s.c. group. We conclude that OGF can be safely administered to patients with advanced pancreatic cancer. Further studies are needed to determine the efficacy of OGF alone or in combination with present modes of therapy for the treatment of pancreatic cancer.

Metastatic breast cancer: overview of treatment

Patients with metastatic breast cancer have a median survival of 2 to 3 years. Twenty percent of the patients who present with bone-only metastasis will be alive at 5 years from diagnosis. Current therapies are aimed at improving the quality of life, symptom control, and prolongation of survival. Newer endocrine and chemotherapeutic drugs are available to the medical oncologist for care of patients with metastatic breast cancer. We will briefly review the new advances in the treatment of metastatic breast cancer.

Serum HER-2/neu and response to the aromatase inhibitor letrozole versus tamoxifen

PURPOSE

To determine the effect of elevated serum HER-2/neu on the response of metastatic breast cancer patients to an aromatase inhibitor versus an antiestrogen.

PATIENTS AND METHODS

Five hundred sixty-two estrogen receptor-positive metastatic breast cancer patients were randomized to first-line hormone therapy with either letrozole or tamoxifen. An automated enzyme-linked immunosorbent assay was used to detect serum HER-2/neu.

RESULTS

For patients with normal serum HER-2/neu (70.5%), objective response rate (ORR; 39% in letrozole-treated patients v 26% in tamoxifen-treated patients; P =.008), clinical benefit (CB; 57% v 45%; P =.016), time to progression (TTP; median, 12.2 v 8.5 months; P =.0019), and time to treatment failure (TTF; median, 11.6 v 6.2 months; P =.0066) were significantly better in patients treated with letrozole. In the elevated HER-2/neu group (29.5%), there was no significant difference in ORR (17% in letrozole-treated patients v 13% in tamoxifen-treated patients; P =.45) or CB (33% v 26%; P =.31), but there was a strong trend in favor of a longer TTP with letrozole (median, 6.1 v 3.3 months; P =.0596) and a significantly longer TTF with letrozole (median, 6.0 v 3.2 months; P =.0418). Multivariate analysis revealed that elevated serum HER-2/neu was a negative predictor for ORR and TTP.

CONCLUSION

Patients with normal serum HER-2/neu receiving letrozole demonstrated a significantly greater ORR and CB and longer TTP and TTF than patients receiving tamoxifen. Although in patients with elevated serum HER-2/neu there was no significant difference between letrozole and tamoxifen in ORR or CB, there was a strong trend favoring longer TTP and significantly longer TTF with letrozole.

Relationship of Serum HER-2/neu and Serum CA 15-3 in Patients with Metastatic Breast Cancer

Background: Serum HER-2/neu antigen concentrations have been reported to correlate with increased tumor volume in patients with breast cancer. We measured serum CA 15-3, a surrogate marker of disease burden, and correlated serum CA 15-3 with serum HER-2/neu and analyzed the association of both markers with clinical outcomes.

Methods: Pretreatment serum samples from 566 patients were retrospectively analyzed from 2 phase III clinical trials of estrogen receptor-positive (ER+), ER−/progesterone receptor-positive, or ER status unknown metastatic breast cancer patients randomized in two similar studies to receive second-line hormone therapy with either megestrol acetate or an aromatase inhibitor (fadrozole). The extracellular domain of the HER-2/neu (c-erbB-2) oncogene and serum CA 15-3 were measured by ELISA on the Bayer Immuno 1.

Results: Serum HER-2/neu protein was increased in 168 patients (30%), and CA 15-3 was increased in 337 (60%) patients. Serum CA 15-3 and HER-2/neu were weakly correlated (r = 0.39; P &lt;0.0001). The clinical benefit (complete responses plus partial responses plus stable disease) of endocrine therapy was significantly lower in patients with increased serum HER-2/neu. When adjusted for serum HER-2/neu, serum CA 15-3 was not predictive of response rates. The median time to progression was shorter in patients with increased serum HER-2/neu (89 days) compared with patients with normal serum HER-2/neu (176 days). Survival was significantly shorter in patients with increased serum HER-2/neu (513 vs 869 days; P &lt;0.0001) or increased serum CA 15-3 (689 vs 939 days; P &lt;0.0001). This observation was confirmed by multivariate analysis.

Conclusions: Serum HER-2/neu is a significant independent predictive and prognostic factor in hormone receptor-positive metastatic breast cancer, even when adjusted for tumor burden as measured by CA 15-3. The combination of increased serum HER-2/neu and increased serum CA 15-3 predicts a worse prognosis than does increased CA 15-3 alone.

Relationship of serum HER-2/neu and serum CA 15-3 in patients with metastatic breast cancer

BACKGROUND

Serum HER-2/neu antigen concentrations have been reported to correlate with increased tumor volume in patients with breast cancer. We measured serum CA 15-3, a surrogate marker of disease burden, and correlated serum CA 15-3 with serum HER-2/neu and analyzed the association of both markers with clinical outcomes.

METHODS

Pretreatment serum samples from 566 patients were retrospectively analyzed from 2 phase III clinical trials of estrogen receptor-positive (ER(+)), ER(-)/progesterone receptor-positive, or ER status unknown metastatic breast cancer patients randomized in two similar studies to receive second-line hormone therapy with either megestrol acetate or an aromatase inhibitor (fadrozole). The extracellular domain of the HER-2/neu (c-erbB-2) oncogene and serum CA 15-3 were measured by ELISA on the Bayer Immuno 1.

RESULTS

Serum HER-2/neu protein was increased in 168 patients (30%), and CA 15-3 was increased in 337 (60%) patients. Serum CA 15-3 and HER-2/neu were weakly correlated (r = 0.39; P <0.0001). The clinical benefit (complete responses plus partial responses plus stable disease) of endocrine therapy was significantly lower in patients with increased serum HER-2/neu. When adjusted for serum HER-2/neu, serum CA 15-3 was not predictive of response rates. The median time to progression was shorter in patients with increased serum HER-2/neu (89 days) compared with patients with normal serum HER-2/neu (176 days). Survival was significantly shorter in patients with increased serum HER-2/neu (513 vs 869 days; P <0.0001) or increased serum CA 15-3 (689 vs 939 days; P <0.0001). This observation was confirmed by multivariate analysis.

CONCLUSIONS

Serum HER-2/neu is a significant independent predictive and prognostic factor in hormone receptor-positive metastatic breast cancer, even when adjusted for tumor burden as measured by CA 15-3. The combination of increased serum HER-2/neu and increased serum CA 15-3 predicts a worse prognosis than does increased CA 15-3 alone.

Elevated serum Her-2/neu level predicts decreased response to hormone therapy in metastatic breast cancer

PURPOSE

To determine the effect of elevation of serum HER-2/neu on response to hormone therapy.

PATIENTS AND METHODS

Seven hundred nineteen metastatic patients with estrogen receptor-positive (ER(+)), progesterone receptor-positive, or both or ER status unknown breast cancer were randomized in three independent clinical trials to receive second-line hormone therapy with either megestrol acetate or an aromatase inhibitor (fadrozole or letrozole). An automated enzyme-linked immunosorbent assay specific for the extracellular domain of the HER-2/neu (c-erbB-2) oncoprotein product was used to detect serum levels.

RESULTS

Two hundred nineteen patients (30%) had elevated serum HER-2/neu protein levels, using the mean + 2 SD (15 ng/mL) from the serum of healthy women as an upper limit. Response to treatment was available for 711 patients. The response rate (complete responses plus partial responses plus stable disease) to endocrine therapy was 45% in 494 patients with non-elevated and 23% in 217 patients with elevated serum HER-2/neu levels (P <.0001). Median duration of treatment response (using the time to progression [TTP] variable for patients who responded) was shorter in the group with elevated serum HER-2/neu levels (11.7 months) compared with the patient group with non-elevated levels (17.4 months). TTP, time to treatment failure, and median survival (17.2 months v 29.6 months) were also significantly shorter in the patients with elevated serum HER-2/neu levels (P <.0001).

CONCLUSION

Patients with ER(+) and serum HER-2/neu-positive metastatic breast cancer are less likely to respond to hormone treatment and have a shorter duration of response than ER(+) and serum HER-2/neu-negative patients. Their survival duration is also shorter.

Receptor-mediated endocytosis of Neisseria gonorrhoeae into primary human urethral epithelial cells: the role of the asialoglycoprotein receptor

Urethral epithelial cells are invaded by Neisseria gonorrhoeae during gonococcal infection in men. To understand further the mechanisms of gonococcal entry into host cells, we used the primary human urethral epithelial cells (PHUECs) tissue culture system recently developed by our laboratory. These studies showed that human asialoglycoprotein receptor (ASGP-R) and the terminal lactosamine of lacto-N-neotetraose-expressing gonococcal lipooligosaccharide (LOS) play an important role in invasion of PHUECs. Microscopy studies showed that ASGP-R traffics to the cell surface after gonococcal challenge. Co-localization of ASGP-R with gonococci was observed. As ASGP-R-mediated endocytosis is clathrin dependent, clathrin localization in PHUECs was examined after infection. Infected PHUECs showed increased clathrin recruitment and co-localization of clathrin and gonococci. Preincubating PHUECs in 0.3 M sucrose or monodansylcadaverine (MDC), which both inhibit clathrin-coated pit formation, resulted in decreased invasion. N. gonorrhoeae strain 1291 produces a single LOS glycoform that terminates with Gal(beta1-4)GlcNac(beta1-3)Gal(beta1-4)Glc (lacto-N-neotetraose). Invasion assays showed that strain 1291 invades significantly more than four isogenic mutants expressing truncated LOS. Sialylation of strain 1291 LOS inhibited invasion significantly. Preincubation of PHUECs in asialofetuin (ASF), an ASGP-R ligand, significantly reduced invasion. A dose-response reduction in invasion was observed in PHUECs preincubated with increasing concentrations of NaOH-deacylated 1291 LOS. These studies indicated that an interaction between lacto-N-neotetraose-terminal LOS and ASGP-R allows gonococcal entry into PHUECs.

The mimicry of human glycolipids and glycosphingolipids by the lipooligosaccharides of pathogenic neisseria and haemophilus

It has been known for many years that bacteria can induce autoimmune responses in humans resulting in serious disease. Recent work has shown that a number of bacteria that colonize human mucosal surfaces exclusively express antigens on their surfaces which are molecular mimics of glycosphingolipids found on human cells. These structures are important in the pathogenesis of Neisseria and Haemophilus species for both immune evasion and in the adherence and invasion of human cells. There is no evidence that colonization or infections by these bacterial species is associated with autoimmune disease.

Modulation of gonococcal piliation by regulatable transcription of pilE

The gonococcal pilus, a member of the type IV family of pili, is composed of numerous monomers of the pilin protein and plays an important role in the initiation of disease by providing the primary attachment of the bacterial cell to human mucosal tissues. Piliation also correlates with efficient DNA transformation. To investigate the relationships between these pilus-related functions, the piliation state, and the availability of pilin, we constructed a derivative of MS11-C9 (DeltapilE1) in which the lacIOP regulatory sequences control pilE transcription. In this strain, MS11-C9.10, the steady-state levels of pilin mRNA and protein directly correlate with the concentration of IPTG (isopropyl-beta-D-thiogalactopyranoside) in the growth medium and can reach near-wild-type levels of expression. Transmission electron microscopy (TEM) demonstrated that the number of pili per cell correlated with the steady-state expression levels: at a low level of transcription, single long pili were observed; at a moderate expression level, many singular and bundled pili were expressed; and upon full gene expression, increased lateral association between pili was observed. Analysis of pilus assembly by TEM and epithelial cell adherence over a time course of induction demonstrated that pili were expressed as early as 1 h postinduction. Analysis at different steady-state levels of transcription demonstrated that DNA transformation efficiency and adherence of MS11-C9.10 to transformed and primary epithelial cells also correlated with the level of piliation. These data show that modulation of the level of pilE transcription, without a change in pilE sequence, can alter the number of pili expressed per cell, pilus bundling, DNA transformation competence, and epithelial cell adherence of the gonococcus.

Gonococcal lipooligosaccharide is a ligand for the asialoglycoprotein receptor on human sperm

In the present study, we show that Neisseria gonorrhoeae lipooligosaccharide (LOS) can bind to the asialoglycoprotein receptor (ASGP-R) on human sperm. This work demonstrates the presence of ASGP-R on human sperm. Binding of purified ASGP-R ligand decreased in the presence of gonococci. Binding of purified iodinated gonococcal LOS identified a protein of molecular weight corresponding to that of human ASGP-R. The presence of excess unlabelled LOS blocked binding of iodinated gonococcal LOS. Binding of wild-type gonococcal LOS to sperm was higher than that of mutant LOS lacking the galactose ligand for ASGP-R. These data suggest that the ASGP-R on human sperm cells recognizes and binds wild-type gonococcal LOS. This interaction may contribute to the transmission of gonorrhea from infected males to their sexual partners.

Macropinocytosis as a mechanism of entry into primary human urethral epithelial cells by Neisseria gonorrhoeae

Gonococcal entry into primary human urethral epithelial cells (HUEC) can occur by macropinocytosis. Scanning and transmission electron microscopy revealed lamellipodia surrounding gonococci, and confocal laser scanning microscopy analysis showed organisms colocalized with M(r) 70,000 fluorescein isothiocyanate-labeled dextran within the cells. Phosphoinositide 3-kinase inhibitors and an actin polymerization inhibitor prevented macropinocytic entry of gonococci into HUEC.

Combined chemoradiotherapy for unresectable pancreatic cancer

This study was undertaken to evaluate the efficacy of a regimen of combined chemoradiotherapy in patients with unresectable adenocarcinoma of the pancreas. An analysis was undertaken on 27 patients from January 1992 to May 1996. Patients had a median age of 70 years (range, 40-78) and Eastern Cooperative Oncology Group Performance Status of 0-2. Eighteen patients had locoregional disease (T2-T3, N0-N1, M0), and nine had metastatic disease. Chemotherapy consisted of four cycles of 5-fluorouracil 1 gm/m2/day as a continuous infusion over 110 hours, streptozotocin 300 mg/m2/day over 30 minutes on days 2-4, and cisplatin 100 mg/m2 over 2 hours on day 4 only, followed by a maintenance regimen of 5-fluorouracil and leucovorin every 2 weeks. The radiotherapy was administered as a split course concurrently with chemotherapy to a total dose of 6000 cGy. Toxicity was frequent, but there were no treatment-related deaths. Grade III and IV toxicity was primarily limited to myelosuppression, stomatitis, and gastrointestinal side effects. Fifteen patients (56%) were able to complete either three or four cycles of chemoradiotherapy. All patients were evaluable for toxicity, response, and survival. Nine patients (33%) had an objective response (four complete response 5 partial response), two remained stable, and 16 (59%) had disease progression. Median survival for the entire group was 19 weeks (2-139), and the median survival for overall responders was 56 weeks (15-139). No patient with localized disease underwent subsequent surgical resection. The authors conclude that those patients who are able to tolerate the entire treatment regimen may achieve a useful prolongation of time to tumor progression.

Use of aromatase inhibitors in breast carcinoma

Aromatase, a cytochrome P-450 enzyme that catalyzes the conversion of androgens to estrogens, is the major mechanism of estrogen synthesis in the post-menopausal woman. We review some of the recent scientific advances which shed light on the biologic significance, physiology, expression and regulation of aromatase in breast tissue. Inhibition of aromatase, the terminal step in estrogen biosynthesis, provides a way of treating hormone-dependent breast cancer in older patients. Aminoglutethimide was the first widely used aromatase inhibitor but had several clinical drawbacks. Newer agents are considerably more selective, more potent, less toxic and easier to use in the clinical setting. This article reviews the clinical data supporting the use of the potent, oral competitive aromatase inhibitors anastrozole, letrozole and vorozole and the irreversible inhibitors 4-OH androstenedione and exemestane. The more potent compounds inhibit both peripheral and intra-tumoral aromatase. We discuss the evidence supporting the notion that aromatase inhibitors lack cross-resistance with antiestrogens and suggest that the newer, more potent compounds may have a particular application in breast cancer treatment in a setting of adaptive hypersensitivity to estrogens. Currently available aromatase inhibitors are safe and effective in the management of hormone-dependent breast cancer in post-menopausal women failing antiestrogen therapy and should now be used before progestational agents. There is abundant evidence to support testing these compounds as first-line hormonal therapy for metastatic breast cancer as well as part of adjuvant regimens in older patients and quite possibly in chemoprevention trials of breast cancer.

Effect of the potent aromatase inhibitor fadrozole hydrochloride (CGS 16949A) in postmenopausal women with breast carcinoma

BACKGROUND

Fadrozole hydrochloride (CGS 16949A) is a highly potent, nonsteroidal aromatase inhibitor that significantly lowers estrogen levels in postmenopausal women and can be effective therapy for patients with advanced hormone-dependent breast carcinoma. Circulating estradiol, estrone, and estrone sulfate are reduced to undetectable levels within weeks of the initiation of therapy. Before this study, it was not known whether this decrease in serum estrogen levels results in altered parameters associated with cardiovascular disease. The authors examined the levels of several critical blood parameters that are important to cardiovascular risk for heart disease and thromboembolic disorders in patients treated with fadrozole.

METHODS

Cholesterol, triglyceride, low density lipoprotein (LDL), high density lipoprotein (HDL), very low density lipoprotein (VLDL), antithrombin III, protein C, protein S, and fibrinogen were serially measured in 21 postmenopausal women with advanced breast carcinoma treated with various doses of fadrozole (1.8 mg/day, n=3; 2.0 mg/day, n=13; 4.0 mg/day, n=5) over 3-24 months (mean, 15.8 months). A repeated measure analysis of variance was applied to each cardiovascular variable to assess changes in the response over time. Analyses were performed separately for each dose group and were also pooled over the dose groups.

RESULTS

There was no statistically significant change over time in lipid parameters, namely, total cholesterol (P=0.57), triglyceride (P=0.27), LDL (P=0.99), HDL (P=0.30), and VLDL (P=0.43), over the 24 months of therapy. There were also no significant changes in coagulation factors, namely, antithrombin III (P=0.41), protein C (P=0.49), or protein S (P=0.31), over the 24 months. However, an increase in fibrinogen that occurred over time did reach statistical significance (P=0.011).

CONCLUSIONS

With the exception of acute phase reactant fibrinogen, this study did not identify an increase in parameters associated with cardiovascular disease in women treated with fadrozole, a potent aromatase inhibitor.

Emerging role of aromatase inhibitors in the treatment of breast cancer

The new generation of potent steroidal and nonsteroidal inhibitors of the enzyme aromatase act by decreasing estrogen production throughout the body in postmenopausal women. The most potent of these agents may also inhibit estrogen synthesis within metastatic breast cancer tissue. The newly developed, orally administered, nonsteroidal competitive inhibitors, such as anastrozole (Arimidex), letrozole (Femara), and vorozole (Rizivor), are a thousand times more potent inhibitors of aromatase than is aminoglutethimide. Furthermore, these agents are highly selective. In several large randomized trials, the new inhibitors produced similar response rates as megestrol acetate (160 mg/d) in postmenopausal women with hormone-dependent breast cancer, but showed a trend toward improved response duration and survival. They also produced less weight gain and fewer cardiovascular and thromboembolic side effects. In addition, letrozole proved superior to aminoglutethimide in another randomized trial. Both anastrozole (1.0 mg/d) and letrozole (2.5 mg/d) have now been approved as second-line treatment for hormone-dependent breast cancer in postmenopausal women in whom disease has progressed following tamoxifen treatment. Either drug should replace the routine use of megestrol acetate in this setting. Ongoing clinical studies are comparing anastrozole and letrozole to antiestrogens as first-line endocrine therapy for metastatic breast cancer. Other trials will study the possible roles of these compounds as adjuvant therapy and chemoprevention for breast cancer.

Issues concerning the role of chemotherapy and hormonal therapy of bone metastases from breast carcinoma

A significant percentage (50-70%) of patients with metastatic breast carcinoma (MBC) will have disease involving the bony skeleton. Clonal selection mediated by parathyroid hormone-related protein and other factors may explain the high incidence of osseous metastases in MBC. The presence of specific growth factors and cytokines in the microenvironment of bone may contribute to the successful establishment and growth of metastatic lesions and also might determine response or resistance of these lesions to chemotherapy or hormonal therapy. Osteolytic bone lesions in MBC frequently give rise to serious clinical problems including bone pain, pathologic fracture, hypercalcemia, and neurologic complications. MBC often is treated with systemic chemotherapy or hormonal therapy. The purpose of this article was to review the recent published literature describing the impact of systemic chemotherapy and hormonal therapy of MBC on the response of bone lesions and their clinical course and complications. Evaluating the response of bone lesions can be problematic and may be complicated by the phenomenon of "tumor flare" that may be observed with either chemotherapy or hormonal therapy. Use of the International Union Against Cancer criteria for the response of bone lesions is recommended. Several studies report objective responses (20-60%) of lytic bone metastases to standard combination chemotherapy regimens such as cyclophosphamide, methotrexate, and 5-fluorouracil and cyclophosphamide, doxorubicin, and 5-fluorouracil, mitoxantrone and 5-FU, newer combinations, and single agents including paclitaxel and docitaxel but responses to vinorelbine may be less frequent. Complete responses of bone lesions to chemotherapy are rare but partial responses and disease stabilization can lead to long term patient benefit. A series from the M. D. Anderson Cancer Center of patients with bone metastases treated with 5-FU, doxorubicin, and cyclophosphamide chemotherapy reported a median duration of response of 14 months. In a recent multicenter study of 195 patients with lytic lesions from MBC treated with chemotherapy, the objective response rate (complete response + partial response) in bone was 18% and 65% of the patients developed at least 1 morbid skeletal event with a median onset of 7.0 months from the start of chemotherapy. Hormone-dependent breast carcinoma has a proclivity to metastasize to bone. In earlier studies comparing aminoglutethimide or medroxyprogesterone acetate with tamoxifen, a higher response rate of bone metastases was observed for the first two agents. However, in more recent studies comparing newer aromatase inhibitors, such as anastrozole, fadrozole, and letrozole, with megestrol acetate, there were no significant differences in rates of response in bone. Patients with MBC with bony lesions respond to both chemotherapy and hormonal therapy and can have a prolonged survival. Therefore such patients are in a more favorable position to benefit from adjunctive supportive therapy such as bisphosphonates intended to reduce skeletal morbidity.

Phase I study combining tumor necrosis factor with interferon-alpha and interleukin-2

We evaluated the effects of the addition of escalating doses of tumor necrosis factor (TNF) to two fixed doses and schedules of a combination of interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) to determine the maximum tolerated dose of this three-cytokine combination and its feasibility as an outpatient regimen. Eighteen patients with metastatic cancer were enrolled. Each course consisted of 3 consecutive weeks of treatment with IFN-alpha 9 x 10(6) IU/m2/day intramuscularly (i.m.) or subcutaneously (s.c.) days 1, 3, and 5 each week for 3 weeks plus IL-2 continuous infusion 1 x 10(6) IU/m2/day (group A) or 3 x 10(6) IU/m2/day (group B) days 1-5 each week for 3 weeks. TNF was administered only during the first week of each course intravenously (i.v.) for 2 h on days 1-5. The dose of TNF was escalated (40, 80, 120 micrograms/m2) in cohorts of 3 patients. The most common side effects were fever, chills, and fatigue in all patients. Grade 3-4 toxicity included anemia (3 patients), thrombocytopenia (1 patients), arrhythmia (2 patients), pulmonary edema (3 patients),- and weight loss (1 patient). Five patients withdrew from study due to toxicity. The combination of the three cytokines is feasible as an outpatient regimen in one of the following combinations: (a) TNF 80 micrograms/m2/day as 2-h infusion on days 1-5 + IL-2 1 x 10(6) IU/m2/day continuous infusion on days 1-5 for 3 weeks + IFN-alpha 9 x 10(6) IU/m2/day s.c. or i.m. on days 1, 3, and 5 for 3 weeks, or (b) TNF 40 micrograms/m2/day as a 2-h infusion on days 1-5 + IL-2 3 x 10(6) IU/m2/day continuous infusion on days 1-5 for 3 weeks + IFN-alpha 9 x 10(6) IU/m2/day s.c. or i.m. on days 1, 3, and 5 for 3 weeks.

Ultrastructural analysis of primary human urethral epithelial cell cultures infected with Neisseria gonorrhoeae

In men with gonococcal urethritis, the urethral epithelial cell is a site of infection. To study the pathogenesis of gonorrhea in this cell type, we have developed a method to culture primary human urethral epithelial cells obtained at the time of urologic surgery. Fluorescent analysis demonstrated that 100% of the cells stained for keratin. Microscopic analyses indicated that these epithelial cells arrayed in a pattern similar to that seen in urethral epithelium. Using immunoelectron and confocal microscopy, we compared the infection process seen in primary cells with events occurring during natural infection of the same cell type in men with gonococcal urethritis. Immunoelectron microscopy studies of cells infected with Neisseria gonorrhoeae 1291 Opa+ P+ showed adherence of organisms to the epithelial cell membrane, pedestal formation with evidence of intimate association between the gonococcal and the epithelial cell membranes, and intracellular gonococci present in vacuoles. Confocal studies of primary urethral epithelial cells showed actin polymerization upon infection. Polyclonal antibodies to the asialoglycoprotein receptor (ASGP-R) demonstrated the presence of this receptor on infected cells in the primary urethral cell culture. In situ hybridization using a fluorescent-labeled probe specific to the ASGP-R mRNA demonstrated this message in uninfected and infected cells. These features were identical to those seen in urethral epithelial cells in exudates from males with gonorrhea. Infection of primary urethral cells in culture mimics events seen in natural infection and will allow detailed molecular analysis of gonococcal pathogenesis in a human epithelial cell which is commonly infected.

The impact of 2D versus 3D quantitation of tumor bulk determination on current methods of assessing response to treatment

PURPOSE

Measurements from sequential axial "2D" data in cancer patients are commonly used to assess treatment response or disease progression. This study compares the volume of tumor bulk calculated with 3D reconstructions with that calculated by conventional methods to determine if it might change patient classification.

METHOD

All medical, gynecologic, and pediatric oncology patients under treatment who were evaluated with serial CT scans between January 1, 1992, and July 31, 1994, for whom the digital data were available were included in this study. For each tumor site, the maximum diameter and its perpendicular were measured and multiplied together to yield an area. The sum of areas of the measured lesions was used as an approximation of overall 2D tumor volume. In addition, the 2D area of each site was multiplied by its height, yielding a 2D volume. Last, the digital data were loaded into a 3D computer system and total 3D tumor volumes determined. All medical and gynecologic oncology patients were treated based upon the 2D area of tumor. The pediatric oncology patients were treated based upon the 2D volume of tumor measured as per standard practice. The members of each treating oncologic service assessed their patients as to how the other two methods would have changed their classification of the patients' response category.

RESULTS

Four hundred thirty-three CT scans were performed in 139 patients, which included 204 baseline and 294 follow-up CT examinations. Seventy patients had new tumor foci and would have been classified as failure by all three methods of tumor bulk measurement. The 3D volume versus the 2D area method of tumor bulk assessment would have changed response categories in 52 of the 294 follow-up CT examinations (p < 0.0001). Thirty-five patients were recategorized from either "no response" to "failure" (21 patients) or "no response" to "response" (14 patients) categories. If only those follow-up studies without new metastatic foci are considered, the 3D volume versus the 2D area methods of tumor assessment would have changed the treatment response category in 23.2%. The use of the 2D volume method of calculating tumor volume of bulk tended to overestimate the overall tumor size by an average of 244 cm3 (p = 0.001).

CONCLUSION

The 3D method of tumor volume measurement differs significantly from conventional 2D methods of tumor volume determination. Large prospective studies analyzing the usefulness of 3D tumor volume measurements and assessing possible changes in patient response categories would be required for full utilization of this more accurate method of following disease bulk.

Aromatase inhibitors in clinical practice: current status and a look to the future

Aromatase inhibitors are a new class of agents that are of considerable interest for potential use as palliative therapy for hormone-dependent metastatic breast cancer in postmenopausal women. In the postmenopausal or castrate female, the process of aromatization accounts for the majority of circulating, biologically active estrogens. This report presents a clinical perspective on some of the most recent information concerning the biology and pharmacology of the aromatase enzyme and highlights the development of newer aromatase inhibitors with important therapeutic potential. Clinical questions addressed include the selection of aromatase inhibitors, the selection of the most appropriate patients for therapy with these new agents, and the positioning of these new agents with respect to other forms of endocrine therapy for breast cancer. Finally, we shall consider areas for future investigation of possible new indications for these agents in clinical medicine.

The role of bisphosphonates in the treatment of bone metastases--the U.S. experience

Frequent complications of bone metastases include pain, pathologic fracture, hypercalcemia and spinal cord compression. Lytic bone metastases result from excessive activation of osteoclasts by tumor-produced cytokines. Aredia (pamidronate) is a potent bisphosphonate that inhibits osteoclast activation. In two dose-seeking phase I trials in patients with breast cancer and prostate cancer, repeated intravenous infusion of Aredia was shown to be safe and effective in reducing bone resorption and pain. In a randomized phase III trial of 377 patients with multiple myeloma, Aredia was administered in a dosage of 90 mg i.v. every 4 weeks. Compared with placebo, treatment with Aredia was associated with a significant decrease in bone pain and in the incidence and time to development of all skeleton-related events. Data from two phase III breast cancer trials each involving 300 patients are now being analyzed. The newer bisphosphonates can safely be used together with standard anticancer therapy to provide effective palliation of symptoms caused by lytic bone metastases.

Phase I trial of recombinant platelet factor 4 (rPF4) in patients with advanced colorectal carcinoma

BACKGROUND

Recombinant platelet factor 4 (rPF4) is a naturally occurring protein found in platelet alpha granules that can inhibit angiogenesis.

METHODS

In this Phase I trial, 9 patients with metastatic colorectal cancer who had failed 5-FU treatment received rPF4 at doses ranging from 0.3 to 3.0 mg/kg via 30-minute infusion. Three additional patients were treated with the 3 mg/kg dose over a 6-hour period of infusion.

RESULTS

The only toxicity encountered was mild leg twitching in 2/3 patients treated with the 6-hour infusion. One patient with a history of phlebitis developed a lower extremity deep venous thrombosis after the first dose of rPF4. A mild rise in fibrinogen level was noted in several patients. Of the 11 evaluable patients, there were no clinical responses to treatment.

CONCLUSIONS

rPF4 is well tolerated at the doses and schedules tested. No clinical responses were observed. Prolonged infusion schedules should be investigated.

Growth inhibition of breast cancer cell lines by combinations of anti-P185HER2 monoclonal antibody and cytokines

The p185HER2 oncogene is associated with poor prognosis in patients with breast cancer. Both anti-p185HER2 MAb and cytokines have been shown to downregulate p185HER2 expression. We investigated the effect of combinations of humanized 4D5, and anti-p185HER2 MAB, and the cytokines IFN-alpha, IFN-gamma or TNF-alpha on the growth of three p185HER2 positive human abreast carcinoma cell lines, SK-BR-3, BT-474, and MDA-MB-453. All three cell lines were treated with IFN-alpha (1000 U/ml) or IFN-gamma (1000 U/ml) or TNF-alpha (100 U/ml) with or without huMAb 4D5 (100 microM), and cell growth was determined on days 3-7. While IFN-alpha, IFN-gamma, TNF-alpha, and huMAb 4D5 all inhibited growth, an apparently additive inhibitory effect occurred using combinations of huMAb 4D5 plus cytokine, with huMAb 4D5 plus TNF-alpha causing the greatest growth inhibition. These results demonstrate the potentiation of growth inhibition of breast cancer cell lines by the combination of anti p185HER2 MAb and cytokines, and suggest that combinations of anti-growth factor receptor MAb and cytokines may be useful in the treatment of breast cancer.