Perceived barriers and facilitators to female condoms among UK based healthcare professionals.

OBJECTIVES: The female condom (FC) is an effective strategy against sexually transmitted infections (STIs) in susceptible women and men who have sex with men. FCs are the only female-initiated dual protection method that protects against both STIs and unintended pregnancy. As healthcare professionals (HCPs) are a key element in the promotion of contraceptive use, it is important to examine attitudes towards FCs among this group. Study participants: 15 male and female HCPs aged between 22 and 57 years recruited from sexual and reproductive health settings located in Brighton, London, and Glasgow. Sampling method: Purposive sampling with targeted advertisements (newsletters and bulletins). Study design: face-to-face and telephone interviews with sexual health HCPs. Main outcome measure: potential barriers and facilitators to FCs in the UK. Data were analysed thematically to identify common views and perspectives. RESULTS: FCs were thought to be unacceptable to most women due to stigma, design, negative visual appeal, insertion difficulties and lack of familiarity. The perceived unavailability and higher cost of FCs, in comparison to male condoms, are major barriers to their use. CONCLUSIONS: HCPs are reluctant to promote FCs, often due to the perceived social stigma surrounding FCs. Further education and promotion are needed to increase acceptability and correct usage. Future research needs to explore strategies to increase the acceptability of FCs among women, men who have sex with men and HCPs.

Targeted advertisement of chlamydia screening on social media: A mixed-methods analysis.

OBJECTIVE: Chlamydia is one of the most common sexually transmitted infections in teenagers and young adults. This study used a mixed-methods analysis to investigate targeted promotion of chlamydia home-testing on social media. METHODS: Our first study, in which face-to-face interviews with young women were conducted, sought to explore their attitudes and preferences towards social media-based health promotion. Our second study used Facebook and Google analytics to examine visits to a chlamydia testing page (where chlamydia testing kits could be ordered online), both before and after a targeted Facebook-based health promotion campaign was conducted. RESULTS: The interviews revealed Facebook to be the preferred choice of social media, with participants perceiving it to be a powerful and far-reaching platform for social interaction. Participants also highlighted several aspects of promotional content to be important at increasing engagement with the target population, including appropriate use of colour, level of interactivity, use of humour and anonymity. The website analysis showed a 277% increase in the direct entrance on the chlamydia testing kit page and a 41% increase in chlamydia test kit orders, in comparison with the baseline period prior to the intervention. CONCLUSIONS: The findings support social media as an engaging medium for the online promotion of chlamydia self-testing and implicate Facebook advertising as a useful tool in addition to community-based chlamydia screening services. Future research needs to identify whether targeted social media-based health promotion could lead to higher chlamydia diagnosis rate in comparison to traditional communication channels.

New agents and approaches to the treatment of B-cell non-Hodgkin lymphoma.

IMPORTANCE OF THE FIELD: B-cell non-Hodgkin lymphoma (NHL) is a significant public health problem as the most common hematologic malignancy in many areas of the world. Current treatments are generally effective, but only a minority of this large group of patients can be cured. AREAS COVERED IN THIS REVIEW: Progress in clinical development of novel, targeted agents and newer cytotoxic agents has led to improved, more durable responses in all major subtypes of NHL. This article covers novel therapeutic agents, which are investigational or registered recently for NHL and/or other cancers. Subtypes of B-cell NHL are addressed separately including relevant papers over the past 20 years. WHAT THE READER WILL GAIN: This review provides a better understanding of studies that have formed the basis for current treatment approaches for B-cell NHL. Also, areas of unmet need are covered. Novel agents are described along with their mechanisms of action, as well as how they might advance the treatment of B-cell NHL. TAKE HOME MESSAGE: This review highlights advancements and the current state of knowledge by presenting clinical trial results as well as preclinical data and advances in prognostic and predictive factors that will pave the way to further progress in NHL.

Enhanced expression of CD74 in gastrointestinal cancers and benign tissues.

CD74, a transmembrane glycoprotein that associates with MHC II, is an important chaperone that regulates antigen presentation for immune response. In addition, CD74 is the receptor for macrophage migration-inhibitory factor which, when bound to CD74, initiates survival pathways and cell proliferation. Formalin fixed, paraffin embedded clinical specimens were evaluated by immunohistochemical procedures for expression of CD74. Overall, expression of CD74 within gastrointestinal carcinomas showed a statistically greater expression than in the normal tissue counterparts (P<0.001 or better). CD74 expression was observed in 95% of pancreatic carcinomas with the majority of cases presenting a mostly intense, diffuse labeling pattern. The results suggested a trend towards greater expression within the higher grade carcinomas (P=0.06). Colorectal and gastric carcinomas gave similar results with 60% and 86%, respectively, positive for CD74 with an intense, diffuse staining pattern. We hypothesized that precursor lesions would express levels of CD74 as high, or higher, than their respective carcinomas, since activation of survival pathways would be of particular importance at the early stages of neoplastic development. For PanIN lesions there was greater expression of CD74 within higher grade, PanIN-3 lesions, whereas the colonic adenomas showed no such trend, but overall, a higher frequency and intensity of CD74 labeling than was observed within the colon carcinomas. These findings are supportive of a role for CD74 in the development and maintenance of gastrointestinal neo-plasia, and provide a rationale for development of therapeutic agents that are able to block CD74 function, specifically within the tumor cell.

A phase I/II trial of fixed-dose docetaxel plus irinotecan and escalating doses of estramustine phosphate for second-line or greater treatment of selected advanced solid tumors.

This phase I/II study evaluated the safety of the combination of irinotecan, docetaxel, and estramustine for selected advanced solid tumors and also obtained initial efficacy data. Twenty-two patients were enrolled in the study. The regimen consisted of docetaxel 30 mg/m(2) and irinotecan 60 mg/m(2) both given intravenously on days 1 and 8 every 21 days in combination with escalating doses of estramustine (500 mg/m(2)/day escalated to 750 mg/m(2)/day on days 0, 1, 2, 7, 8, and 9 given every 21 days) during phase I. Dose escalation was continued until the maximum planned dose level of estramustine (750 mg/m(2)/day) was reached. After the appropriate phase II dose of estramustine was found additional patients were enrolled. Twenty-one of the 22 patients were evaluable for toxicity and 17 for tumor response. The recommended phase II dose of estramustine was found to be 750 mg/m(2)/day orally on days 0, 1, 2, 7, 8, and 9 given every 21 days. Hematologic toxicity was fairly mild, with only one episode of grade 3 neutropenia. Diarrhea was the most common nonhematologic toxicity with grade 3 toxicity occurring in five of 21 patients. Only one episode of venous thrombosis was observed. Objective response rate was 15.8%, overall clinical benefit rate was 63%, and median time to progression was 15 weeks. Estramustine in combination with the doublet of docetaxel and irinotecan is a well-tolerated regimen with minimal hematologic toxicity, mild to moderate nonhematologic toxicity, and promising initial antitumor activity in previously treated patients with advanced solid tumors.

Enhanced histone deacetylase enzyme activity in primary myelofibrosis.

We measured histone deacetylase (HDAC) activity in 17 patients with primary myelofibrosis (PMF); 19 with other myeloproliferative neoplasm (MPN) and 16 normal volunteers. Significantly elevated HDAC levels were shown in patients with PMF compared with other MPN patients and normal volunteers (p<0.05). Sixteen patients with PMF were also studied for correlation between JAK2 mutation status and HDAC levels; no significant correlation was found. We further correlated HDAC levels with clinical features in PMF: there was no correlation with WBC, platelet counts, Hb levels or degree of bone marrow fibrosis, but HDAC levels were correlated to the degree of splenomegaly. This suggests that HDAC may be recruited as essential thrombocythemia or polycythemia vera progresses into myelofibrosis or PMF progresses into more advanced stage. We then used the qRT-PCR cycle threshold (CT) method to study which HDACs were elevated in PMF. The results showed that, in general, Class 1 HDACs were elevated (HDAC1,2,8) except HDAC3, Class II HDACs were depressed (HDAC4,5) except HDAC6 and 10, and Class III HDACs were generally elevated. The current study may form the basis for using HDAC inhibitor in the treatment of patients with PMF and may implicate a possible role of HDAC in the association of pathogenesis of PMF.

Potential of peroxisome proliferator-activated receptor gamma antagonist compounds as therapeutic agents for a wide range of cancer types.

PPARgamma is a therapeutic target that has been exploited for treatment of type II diabetes mellitus (T2DM) with agonist drugs. Since PPARgamma is expressed by many hematopoietic, mesodermal and epithelial cancers, agonist drugs were tested and shown to have both preclinical and clinical anticancer activities. While preclinical activity has been observed in many cancer types, clinical activity has been observed only in pilot and phase II trials in liposarcoma and prostate cancer. Most studies address agonist compounds, with substantially fewer reports on anticancer effects of PPARgamma antagonists. In cancer model systems, some effects of PPARgamma agonists were not inhibited by PPARgamma antagonists, suggesting noncanonical or PPARgamma-independent mechanisms. In addition, PPARgamma antagonists, such as T0070907 and GW9662, have exhibited antiproliferative effects on a broad range of hematopoietic and epithelial cell lines, usually with greater potency than agonists. Also, additive antiproliferative effects of combinations of agonist plus antagonist drugs were observed. Finally, there are preclinical in vivo data showing that antagonist compounds can be administered safely, with favorable metabolic effects as well as antitumor effects. Since PPARgamma antagonists represent a new drug class that holds promise as a broadly applicable therapeutic approach for cancer treatment, it is the subject of this review.

CD74: a new candidate target for the immunotherapy of B-cell neoplasms.

CD74 is an integral membrane protein that functions as a MHC class II chaperone. Moreover, it has recently been shown to have a role as an accessory-signaling molecule and has been implicated in malignant B-cell proliferation and survival. These biological functions combined with expression of CD74 on malignant B cells and limited expression on normal tissues implicate CD74 as a potential therapeutic target. The anti-CD74 monoclonal antibody LL1 has been humanized (hLL1 milatuzumab or IMMU-115) and can provide the basis for novel therapeutic approaches to B-cell malignancies, particularly because this antibody shows rapid internalization into CD74+ malignant cells. This article reviews the preclinical evaluations of LL1, its humanized form, and isotope, drug, and toxin conjugates. These studies show that unconjugated hLL1 and conjugates of hLL1 constructs with radioisotopes, doxorubicin, and frog RNase have high antitumor activity in non-Hodgkin's lymphoma and multiple myeloma in vitro and in tumor xenograft models. Single-dose studies of hLL1 in monkeys showed no adverse effects but did decrease circulating B and T lymphocytes and natural killer cells. When evaluated in combination with rituximab, either equivalent or improved efficacy, compared with either antibody alone, was observed. CD74 is a new candidate target for the immunotherapy of neoplasms expressing this antigen, which can be exploited using either a naked antibody or conjugated to isotopes, drugs, or toxins.

Peroxisome proliferator-activated receptor-gamma antagonists exhibit potent antiproliferative effects versus many hematopoietic and epithelial cancer cell lines.

Peroxisome proliferator-activated receptor-gamma ligands have preclinical and clinical anticancer activity. Most studies in this area address agonists, with relatively few reports on anticancer effects of peroxisome proliferator-activated receptor-gamma antagonists. Thus, we evaluated the two pure peroxisome proliferator-activated receptor-gamma antagonists, T0070907 and GW9662, on a panel of hematopoietic and epithelial cell lines. The peroxisome proliferator-activated receptor-gamma antagonists and a reference agonist (pioglitazone) were tested in an in-vitro proliferation assay on a panel of seven hematopoietic and nine epithelial cancer cell lines, some of which are chemoresistant. Peroxisome proliferator-activated receptor-gamma expression was measured by immunoblotting, as was the effect of treatment with these agents on peroxisome proliferator-activated receptor-gamma levels. The effect of exogenous interleukin-6, an antiapoptotic cytokine, on growth inhibition was evaluated as well as the apoptotic effects of these drugs. The peroxisome proliferator-activated receptor-gamma antagonists showed significantly greater potency on all cell lines (IC50s of 3.2-29.7 versus 26.5-78.7 micromol/l for pioglitazone) and greater maximum growth inhibition. Peroxisome proliferator-activated receptor-gamma levels did not correlate with growth inhibition in this panel of cell lines. Combinations of peroxisome proliferator-activated receptor-gamma antagonists and the agonist actually showed schedule-dependent increases in growth inhibition. Exogenous interleukin-6 did not induce resistance to these agents. Both the antagonists and the agonist induced apoptosis, but only the former drugs showed caspase dependence. These two peroxisome proliferator-activated receptor-gamma antagonists have significantly more potent in-vitro antiproliferative effects versus hematopoietic and epithelial cancer cell lines. This effect does not correlate with peroxisome proliferator-activated receptor-gamma levels, suggesting alternative mechanisms or other targets of action. These findings support further translational studies to explore the mechanism of action and therapeutic potential of this class of agents.

The MTT assay to evaluate chemosensitivity.

The assessment of the degree or rate of cellular proliferation and cell viability is critical to the assessment of the effects of drugs, antibodies, or cytokines on both normal and malignant cell populations. This can be accomplished by either direct or indirect counting methods. Direct counting by manual or automated methods, using a hemacytometer or particle counter, respectively, allows for serial cell counting at multiple time points, but these are low-throughput approaches. High-throughput and robust alternatives to direct counting utilize either radiotracers (e.g., 3H-thymidine) or dye compounds, which can be adapted to multiwell culture plate formats. This chapter focuses on the use of tetrazolium-type indicator dyes, of which the compound 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) has been the most widely utilized. Newer tetrazolium dyes that yield water-soluble products and offer added flexibility, increases in sensitivity, and fewer steps, which are offset by increased costs, are also covered.

A phase I trial combining high-dose 90Y-labeled humanized anti-CEA monoclonal antibody with doxorubicin and peripheral blood stem cell rescue in advanced medullary thyroid cancer.

UNLABELLED: This trial determined the pharmacokinetics, dosimetry, and dose-limiting toxicity of 90Y-hMN-14 IgG (humanized anticarcinoembryonic antigen [CEA, or CEACAM5] monoclonal antibody; labetuzumab), combined with doxorubicin and peripheral blood stem cell (PBSC) support in advanced medullary thyroid cancer (MTC) patients. METHODS: Fifteen patients received an infusion of 111In-hMN-14 IgG. One to 2 wk later, 14 patients received 90Y-hMN-14 IgG, starting at 740 MBq/m2, followed 24 h later with a fixed intravenous bolus dose of doxorubicin (60 mg/m2). Preharvested PBSCs were reinfused when the 90Y activity in the body was < or =111 MBq/m2. RESULTS: The mean red marrow dose estimated for the 90Y-hMN-14 IgG was 1.65 +/- 0.59 mGy/MBq (n = 11), with normal organs ranging from approximately 2.3 to 4.4 mGy/MBq. Eighty percent of all known lesions (125/156), including 78 of 79 bone and 16 putatively occult lesions, were targeted. The average radiation dose to the tumor was 15.1 +/- 10.8 mGy/MBq (55.8 +/- 39.8 cGy/mCi) 90Y-hMN-4 IgG (n = 29 tumors in 8 patients), with a majority of the lesions receiving >2,000 cGy at an administered dose of < or =1,480 MBq/m2. The average tumor-to-red marrow, tumor-to-liver, tumor-to-lungs, and tumor-to-kidneys ratios were 15.0 +/- 11.0, 5.1 +/- 3.6, 6.9 +/- 6.1, and 9.0 +/- 8.7, respectively. Cardiopulmonary toxicity was dose limiting at 1,850 MBq/m2. Minor responses were noted in 2 patients and 1 patient had a partial response (68% reduction in local and hepatic metastatic disease). CONCLUSION: This treatment combination was well tolerated with complete recovery of blood counts and reversible nonhematologic toxicities at the maximum tolerated dose of 1,480 MBq/m2. Evidence of antitumor response in these patients with advanced cancer was modest, but encouraging; this type of treatment may be more successful if applied to more limited, earlier-stage disease.

Radioimmunotherapy of non-Hodgkin's lymphoma: a critical appraisal.

Radioimmunotherapy is a unique form of radiation therapy that uses antibodies to specifically target radionuclides for systemic cancer treatment. While chemotherapy remains the frontline treatment for non-Hodgkin's lymphoma, two radioimmunotherapy agents are approved for use in certain follicular and transformed forms of recurrent non-Hodgkin's lymphoma as a second- or third-line treatment option. However, there are number of clinical trials underway that will likely lead to a more expanded use of this treatment modality in the future. New agents and approaches for radioimmunotherapy are also being developed that could offer an even greater potential for this new form of therapy.

CD74 is expressed by multiple myeloma and is a promising target for therapy.

PURPOSE: CD74 (HLA-DR-associated invariant chain) plays a role in antigen presentation. In addition to its expression on antigen-presenting cells, it is expressed by carcinomas of renal, lung, gastric, and thymic origin and by certain sarcomas. The restricted expression of CD74 by normal tissues and its very rapid internalization make CD74 an attractive therapeutic target for both cancer and immunologic diseases. Preclinical efficacy of anti-CD74 monoclonal antibody (mAb) therapy has been demonstrated in B-lymphoma models. Because there are few validated antigenic targets in multiple myeloma, CD74 expression was examined. EXPERIMENTAL DESIGN: CD74 expression was assessed by immunohistochemistry in bone marrow biopsies of known multiple myeloma cases. Its expression was measured by flow cytometry in multiple myeloma lines, and CD74 mRNA expression was determined by reverse transcription-PCR. In addition, the in vitro antiproliferative effect of LL1 mAb was evaluated on a CD74+ multiple myeloma cell line using a [3H]thymidine incorporation assay. RESULTS: CD74 expression was observed in 19 of 22 cases of multiple myeloma, with most expressing moderate to high levels in the majority of malignant plasma cells. CD74 was expressed by most multiple myeloma cell lines, as was CD74 mRNA, at levels mirroring CD74 protein. Also, unlabeled LL1 mAb mediated in vitro growth inhibition of a CD74+ multiple myeloma cell line. CONCLUSIONS: CD74 expression is frequent in multiple myeloma, with predominant expression by the malignant plasma cells. Because anti-CD74 mAbs internalize very rapidly and LL1 mAb has shown efficacy in B-lymphoma models, CD74 represents a novel and promising target for treatment of multiple myeloma. Therefore, LL1 mAb is well suited as a carrier of radionuclides, drugs, or toxins, and also has activity as an unlabeled mAb, thereby supporting its development for this unmet need in cancer therapy.

Radioimmunotherapy of non-Hodgkin's lymphoma with 90Y-DOTA humanized anti-CD22 IgG (90Y-Epratuzumab): do tumor targeting and dosimetry predict therapeutic response?

UNLABELLED: A DOTA (1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic acid)-conjugated, (111)In- and (90)Y-labeled humanized antibody to CD22, epratuzumab, was studied in patients with non-Hodgkin's lymphoma (NHL) to assess biodistribution and tumor targeting, pharmacokinetics, dosimetry, and anti-antibody response. Of particular interest was to evaluate whether pretherapy targeting and tumor dosimetry could predict therapeutic responses. METHODS: Patients received a pretherapy imaging study with (111)In-DOTA-epratuzumab IgG (0.75 mg/kg), followed about 1 wk later with (90)Y-DOTA-epratuzumab starting at a dose level of 0.185 GBq/m(2) (5 mCi/m(2)) in patients who had prior high-dose chemotherapy (group 2), and at 0.370 GBq/m(2) in patients who did not have a prior transplant (group 1), with escalation in 0.185-GBq/m(2) increments. RESULTS: The effective blood half-life for (111)In-DOTA epratuzumab was 36.1 +/- 7.9 h (n = 25) compared with 35.2 +/- 7.0 h for (90)Y-DOTA-epratuzumab (n = 22). The whole-body half-life for (90)Y-DOTA-epratuzumab estimated from (111)In-DOTA-epratuzumab scintigraphy was 58.3 +/- 4.7 h (n = 20), with urine collection confirming the loss of between 2.2% and 15.9% of the injected activity over 3 d (n = 3). One-hundred sixteen of 165 CT-confirmed lesions were visualized with (111)In-DOTA-epratuzumab. Radiation-absorbed doses to liver, lungs, and kidneys averaged 0.55 +/- 0.13 (n = 17), 0.28 +/- 0.06 (n = 17), and 0.38 +/- 0.07 mGy/MBq (n = 10), respectively, with 0.14 +/- 0.02 and 0.23 +/- 0.04 mGy/MBq delivered to the whole-body and red marrow, respectively. Tumor doses (n = 14 lesions in 10 patients) ranged from 1.0 to as much as 83 mGy/MBq for a 0.5-g lesion (median, 7.15 mGy/MBq). Group 2 patients were more likely to experience significant hematologic toxicities, but doses of up to 0.370 GBq/m(2) of (90)Y-DOTA-epratuzumab were tolerated with standard support measures, whereas patients in group 1 tolerated doses of up to 0.740 GBq/m(2) with the potential for further escalation. Anti-tumor effects were seen in both indolent and aggressive NHL. The data also suggest that anti-tumor responses of potentially equal magnitude can occur irrespective of tumor targeting and tumor size. Hence, tumor response did not correlate with the radiation dose delivered or with the tumor being visualized by external imaging. An anti-antibody response to epratuzumab was detected by an enzyme-linked immunosorbent assay in only 2 of 16 patients. CONCLUSION: These results suggest that (90)Y-DOTA-epratuzmab is a promising agent for the treatment of NHL and warrants further study. There was evidence suggesting that in this system, factors other than tumor radiation dose and targeting may be involved in the success of radioimmunotherapy.

Phase I radioimmunotherapy trial with iodine-131--labeled humanized MN-14 anti-carcinoembryonic antigen monoclonal antibody in patients with metastatic gastrointestinal and colorectal cancer.

This trial was conducted to determine the pharmacokinetics, dosimetry, dose-limiting toxicity, and the maximum tolerated dose of iodine-131 humanized MN-14 immunoglobulin G (131I-hMN-14 IgG), a humanized complementary-determining region-grafted anti-carcinoembryonic antigen monoclonal antibody, in metastatic gastrointestinal and colorectal cancer patients. Patients were divided into 2 groups: group A consisted of patients who had prior external beam radiation therapy (n = 8), and group B included patients who had received standard chemotherapy (n = 13). All patients received a diagnostic infusion of 131I-hMN-14 IgG (approximately 8.0 mCi, 15 mg/m2) to study the pharmacokinetics, biodistribution, and dosimetry. One week later, 17 of 21 patients received infusional therapy of escalating radioactive doses of 131I-hMN-14 IgG. Blood pharmacokinetics and quantitative imaging were performed again after the therapeutic dose. Radiation-absorbed doses to normal organs and tumors were determined by MIRDOSE-3 algorithms. The primary dose-limiting toxicity was hematologic toxicity at 40 mCi/m2. The blood half-life (n = 20) was identical for the diagnostic and therapy infusions. The mean red marrow dose was 2.2 +/- 2.4 cGy/mCi. The mean tumor radiation dose (n = 8) was 24.2 +/- 22.6 cGy/mCi. Tumor targeting was seen in most large metastatic lesions. No objective responses were seen in these heavily pretreated and mostly advanced patients. In conclusion, 131I-hMN-14 IgG has good targeting, good tumor to normal organs radiation absorbed ratios, and an acceptable toxicity profile in advanced metastatic gastrointestinal and colorectal cancer patients.

Celecoxib exhibits the greatest potency amongst cyclooxygenase (COX) inhibitors for growth inhibition of COX-2-negative hematopoietic and epithelial cell lines.

Cyclooxygenase-2 (COX-2) is an important cellular target for both therapy and/or prevention of inflammatory disorders and cancer. The advent of selective COX-2 inhibitors now allows a more precise and safer treatment approach. The screening of an array of cancer cell lines for growth inhibitory effects of COX-2-selective and -nonselective inhibitors, including celecoxib (Celebrex) and rofecoxib (Vioxx), produced two unanticipated findings. Firstly, the antiproliferative effects of celecoxib were noted to be of very similar magnitude for both hematopoietic and epithelial cancer cell lines. Most hematopoietic cell lines had no detectable COX-2 expression by reverse transcription-PCR, and none expressed COX-2 protein. In addition, COX-2-negative epithelial lines were found to have IC50s for celecoxib that were very similar to their COX-2+ counterparts. Thus, important antiproliferative effects were observed that were independent of both the cell lineage and COX-2 status. Secondly, it was also observed that COX-2 inhibitor drugs, celecoxib and rofecoxib, with similar COX-2-selectivity and clinical efficacy for inflammatory indications, differed significantly in their in vitro antiproliferative effects on cancer cell lines. IC50s of 35-65 microM were observed for celecoxib across this entire panel of cell lines. Finally, no difference in the mode or degree of cytotoxicity was apparent between cell lines, because similar levels of apoptosis were observed in COX-2+ and -negative cell lines after treatment with celecoxib, with correspondingly lower levels after rofecoxib treatment. These data are important in that they provide the first direct comparison of epithelial and hematopoietic cancer cell lines, as well as a direct comparison of the in vitro anticancer effects of the two clinically available COX-2 inhibitors.