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INTRODUCTION:Onapristone is a type I progesterone receptor (PR) antagonist, which prevents PR- mediated DNA transcription. Onapristone is active in multiple preclinical models and two prior studies demonstrated promising activity in patients with breast cancer. We conducted a study of extended release (ER) Onapristone to determine a recommended dose and explore the role of transcriptionally-activated PR (APR), detected as an aggregated subnuclear distribution pattern, as a predictive biomarker. METHODS:An open-label, multicenter, randomized, parallel-group, phase 1 study (target n = 60; NCT02052128) included female patients ≥18 years with PRpos tumors. APR analysis was performed on archival tumor tissue. Patients were randomized to five cohorts of extended release (ER) onapristone tablets 10, 20, 30, 40 or 50 mg BID, or immediate release 100 mg QD until progressive disease or intolerability. Primary endpoint was to identify the recommended phase 2 dose. Secondary endpoints included safety, clinical benefit and pharmacokinetics. RESULTS:The phase 1 dose escalation component of the study is complete (n = 52). Tumor diagnosis included: endometrial carcinoma 12; breast cancer 20; ovarian cancer 13; other 7. Median age was 64 (36-84). No dose limiting toxicity was observed with reported liver function test elevation related only to liver metastases. The RP2D was 50 mg ER BID. Median therapy duration was 8 weeks (range 2-44), and 9 patients had clinical benefit ≥24 weeks, including 2 patients with APRpos endometrial carcinoma. CONCLUSION:Clinical benefit with excellent tolerance was seen in heavily pretreated patients with endometrial, ovarian and breast cancer. The data support the development of Onapristone in endometrial endometrioid cancer. Onapristone should also be evaluated in ovarian and breast cancers along with APR immunohistochemistry validation.

The purpose of this study was to examine female varsity athletes' perceptions of teammate conflict. Semistructured interviews were conducted with 19 female varsity athletes (M age = 21.17 years) from four sport teams. Analysis revealed that conflict was a prevalent feature of playing on their teams. Conflict relating to performance and relationships was identified. Strategies athletes thought may help create conditions for managing conflict were to (a) engage in team building early in the season, (b) address conflict early, (c) engage mediators in the resolution of conflict, and (d) hold structured (rather than unstructured) team meetings. It also seemed that athletes required personal conflict resolution skills. These findings are compared with previous research and offered as implications for professional practice. [ABSTRACT FROM AUTHOR]

Introduction: Onapristone is a type I progesterone receptor (PR) antagonist, which prevents PR- mediated DNA transcription. Onapristone is active in multiple preclinical models and two prior studies demonstrated promising activity in patients with breast cancer. We conducted a study of extended release (ER) Onapristone to determine a recommended dose and explore the role of transcriptionally-activated PR (APR), detected as an aggregated subnuclear distribution pattern, as a predictive biomarker. Methods: An open-label, multicenter, randomized, parallel-group, phase 1 study (target n = 60; NCT02052128) included female patients ≥18 years with PRpos tumors. APR analysis was performed on archival tumor tissue. Patients were randomized to five cohorts of extended release (ER) onapristone tablets 10, 20, 30, 40 or 50 mg BID, or immediate release 100 mg QD until progressive disease or intolerability. Primary endpoint was to identify the recommended phase 2 dose. Secondary endpoints included safety, clinical benefit and pharmacokinetics. Results: The phase 1 dose escalation component of the study is complete (n = 52). Tumor diagnosis included: endometrial carcinoma 12; breast cancer 20; ovarian cancer 13; other 7. Median age was 64 (36–84). No dose limiting toxicity was observed with reported liver function test elevation related only to liver metastases. The RP2D was 50 mg ER BID. Median therapy duration was 8 weeks (range 2–44), and 9 patients had clinical benefit ≥24 weeks, including 2 patients with APRpos endometrial carcinoma. Conclusion: Clinical benefit with excellent tolerance was seen in heavily pretreated patients with endometrial, ovarian and breast cancer. The data support the development of Onapristone in endometrial endometrioid cancer. Onapristone should also be evaluated in ovarian and breast cancers along with APR immunohistochemistry validation. [ABSTRACT FROM AUTHOR]

Lessons Learned: The fibrolamellar carcinoma-associated DNAJB1-PRKACA gene fusion transcript RNA codes for the catalytic domain of protein kinase A and, thus, overexpression of Aurora kinase A. ENMD-2076 showed a favorable toxicity profile. The limited results, one patient (3%) with a partial response and 57% of patients with stable disease, do not support further evaluation of ENMD-2076 as single agent. Future studies will depend on the simultaneous targeting approach of DNAJB1-PRKACA and the critical downstream components., Background: Fibrolamellar carcinoma (FLC) represents approximately 0.85% of liver cancers. The associated DNAJB1-PRKACA gene fusion transcript RNA codes for the catalytic domain of protein kinase A and overexpression of Aurora kinase A (AURKA). ENMD-2076 is a selective anti-AURKA inhibitor., Methods: Patients aged >12 years with pathologically confirmed incurable FLC, with measurable disease, Eastern Cooperative Oncology Group performance status 0-2 or Lansky 70-100, and adequate organ function were eligible. Patients were prescribed ENMD-2076 based on body surface area. The primary endpoint was overall objective response rate by RECIST v1.1, with a null hypothesis of true response rate of 2% versus one-sided alternative of 15%. Secondary endpoints included 6-month progression-free survival (PFS) rate (Fig. 1), median PFS, time to progression (TTP), and overall survival (OS). Safety was evaluated throughout the study., Results: Of 35 patients who enrolled and received treatment, 1 (3%) had a partial response (PR) and 20 (57%) had stable disease (SD). Median TTP, PFS, and OS were 5, 3.9, and 19 months, respectively. The most frequently reported drug-related serious adverse event was hypertension in three patients. Three deaths were reported on-study-two due to disease progression and one due to pulmonary embolism not related to ENMD-2076., Conclusion: The study provided no rationale for further studying ENMD-2076 as a single agent in FLC., (© AlphaMed Press; the data published online to support this summary is the property of the authors.)

Prion diseases are fatal infectious neurodegenerative disorders that affect both humans and animals. The autocatalytic conversion of the cellular prion protein (PrP C ) into the pathologic isoform PrP Sc is a key feature in prion pathogenesis. AR-12 is an IND-approved derivative of celecoxib that demonstrated preclinical activity against several microbial diseases. Recently, AR-12 has been shown to facilitate clearance of misfolded proteins. The latter proposes AR-12 to be a potential therapeutic agent for neurodegenerative disorders. In this study, we investigated the role of AR-12 and its derivatives in controlling prion infection. We tested AR-12 in prion infected neuronal and non-neuronal cell lines. Immunoblotting and confocal microscopy results showed that AR-12 and its analogue AR-14 reduced PrP Sc levels after only 72 hours of treatment. Furthermore, infected cells were cured of PrP Sc after exposure of AR-12 or AR-14 for only two weeks. We partially attribute the influence of the AR compounds on prion propagation to autophagy stimulation, in line with our previous findings that drug-induced stimulation of autophagy has anti-prion effects in vitro and in vivo. Taken together, this study demonstrates that AR-12 and the AR-14 analogue are potential new therapeutic agents for prion diseases and possibly protein misfolding disorders involving prion-like mechanisms.

We have recently demonstrated that AR-12 (OSU-03012) reduces the function and ATPase activities of multiple HSP90 and HSP70 family chaperones. Combined knock down of chaperones or AR-12 treatment acted to reduce the expression of virus receptors and essential glucosidase proteins. Combined knock down of chaperones or AR-12 treatment inactivated mTOR and elevated ATG13 S318 phosphorylation concomitant with inducing an endoplasmic reticulum stress response that in an eIF2α-dependent fashion increased Beclin1 and LC3 expression and autophagosome formation. Over-expression of chaperones prevented the reduction in receptor/glucosidase expression, mTOR inactivation, the ER stress response, and autophagosome formation. AR-12 reduced the reproduction of viruses including Mumps, Influenza, Measles, Junín, Rubella, HIV (wild type and protease resistant), and Ebola, an effect replicated by knock down of multiple chaperone proteins. AR-12-stimulated the co-localization of Influenza, EBV and HIV virus proteins with LC3 in autophagosomes and reduced viral protein association with the chaperones HSP90, HSP70, and GRP78. Knock down of Beclin1 suppressed drug-induced autophagosome formation and reduced the anti-viral protection afforded by AR-12. In an animal model of hemorrhagic fever virus, a transient exposure of animals to low doses of AR-12 doubled animal survival from ∼30% to ∼60% and suppressed liver damage as measured by ATL, GGT and LDH release. Thus through inhibition of chaperone protein functions; reducing the production, stability and processing of viral proteins; and stimulating autophagosome formation/viral protein degradation, AR-12 acts as a broad-specificity anti-viral drug in vitro and in vivo. We argue future patient studies with AR-12 are warranted. J. Cell. Physiol. 231: 2286-2302, 2016. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

We performed proteomic studies using the GRP78 chaperone-inhibitor drug AR-12 (OSU-03012) as bait. Multiple additional chaperone and chaperone-associated proteins were shown to interact with AR-12, including: GRP75, HSP75, BAG2; HSP27; ULK-1; and thioredoxin. AR-12 down-regulated in situ immuno-fluorescence detection of ATP binding chaperones using antibodies directed against the NH2-termini of the proteins but only weakly reduced detection using antibodies directed against the central and COOH portions of the proteins. Traditional SDS-PAGE and western blotting assessment methods did not exhibit any alterations in chaperone detection. AR-12 altered the sub-cellular distribution of chaperone proteins, abolishing their punctate speckled patterning concomitant with changes in protein co-localization. AR-12 inhibited chaperone ATPase activity, which was enhanced by sildenafil; inhibited chaperone - chaperone and chaperone - client interactions; and docked in silico with the ATPase domains of HSP90 and of HSP70. AR-12 combined with sildenafil in a GRP78 plus HSP27 -dependent fashion to profoundly activate an eIF2α/ATF4/CHOP/Beclin1 pathway in parallel with inactivating mTOR and increasing ATG13 phosphorylation, collectively resulting in formation of punctate toxic autophagosomes. Over-expression of [GRP78 and HSP27] prevented: AR-12 -induced activation of ER stress signaling and maintained mTOR activity; AR-12 -mediated down-regulation of thioredoxin, MCL-1 and c-FLIP-s; and preserved tumor cell viability. Thus the inhibition of chaperone protein functions by AR-12 and by multi-kinase inhibitors very likely explains why these agents have anti-tumor effects in multiple genetically diverse tumor cell types.

Based on preclinical studies which reveal enhanced antitumor activity of tumor necrosis factor (TNF) when combined with actinomycin D in human prostate cancer cell lines, we performed a phase I clinical study combining TNF and actinomycin D. All patients had metastatic prostatic carcinoma exhibiting androgen-independent growth. Patients were treated with a combination of a short infusion of actinomycin D followed by a TNF infusion daily for five consecutive days. Soluble TNF receptor p60 was not modulated by treatment but p80 receptor increased significantly following treatment with a combination of TNF and actinomycin D (baseline median 3.4 ng/ml) range 2.5-6.6 ng/ml follow up (9.3 ng/ml) range 6-24 ng/ml. We concluded that the maximum tolerated dose of continuous infusion TNF and short infusion actinomycin D is 400 micrograms/m2 of actinomycin D and 400 micrograms/m2 of TNF. The increased soluble receptor isoform (p80) may account for the lack of clinical activity seen in this trial. Should these results be confirmed, a strategy focused on overcoming the upregulation of the TNF soluble receptor will be required before further study of TNF should be considered.

Purpose: Hematopoietic growth factors have been shown to ameliorate the side effects of chemotherapy. Here we assess the ability of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) to increase the dose-intensity and reduce the side effects of escalated methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) chemotherapy., Patients and Methods: A prospective randomized trial to compare escalated MVAC versus escalated MVAC with rhGM-CSF was conducted. All patients were treated at The University of Texas M.D. Anderson Cancer Center (UTMDACC) and had a metastatic or unresectable urothelial tumor. Forty-eight patients were randomized (25 to MVAC with rhGM-CSF and 23 to escalated MVAC alone). The clinical characteristics of the study populations were similar (ie, degree of tumor dissemination and performance status)., Results: The dose-intensity in the two arms of the study did not differ significantly. No difference in the frequency of bacteriologically documented infections occurred between the two study arms., Conclusion: The use of the hematopoietic growth factor rhGM-CSF did not result in an increased dose-intensity of escalated MVAC. The inability to increase the dose-intensity of MVAC further was a result of nonhematologic side effects of the chemotherapy. Escalation of treatment delivered at its median-tolerated dose is unlikely to result in additional therapeutic benefit for patients with common solid tumors. Future development of therapy may require the development of new agents or concepts, rather than modification of existing therapies.

We conducted a phase II trial to confirm the activity of fixed, low dose gamma-interferon in metastatic renal cell carcinoma. A total of 35 patients with metastatic renal cell carcinoma, who had not received prior immunotherapy and who had a Zubrod performance status of 2 or less, was enrolled in this study. Primary tumors were controlled by nephrectomy or embolization before treatment began. gamma-Interferon was administered weekly as a subcutaneous injection at a fixed dose of 100 micrograms. Toxic effects were limited to low grade fever, chills and myalgias within 24 hours of injection. There were no incidences of grade 3 or 4 toxicity. Responses could be evaluated in 34 patients. There were 1 complete and 4 partial responses, for an objective response rate of 15% (95% confidence interval 5 to 32%). Durations of response to date are 21+, 17+, 13+, 9 and 2 months. We conclude that gamma-interferon is an active agent for metastatic renal cell carcinoma when administered according to this dose and schedule. The response rate compares favorably with those of alpha-interferon and interleukin-2, and toxicity is minimal. gamma-Interferon has excellent potential for use in combination with other biological or chemotherapeutic agents and in the adjuvant setting.

Interferon-alpha (IFN-alpha) and interleukin-2 (IL-2) each has produced a 15%-20% response in metastatic renal cell cancer. Combining IFN-alpha with either IL-2 or 5-fluorouracil (5-FU) enhanced IFN-alpha activity. We have therefore conducted a Phase I Study combining IL-2, IFN-alpha, and 5-FU. The patients were continuously infused with IL-2 (1-3 x 10(6) u/m2) and 5-FU (600-750 mg/m2) for a 5-day period every 28 days, and IFN-alpha (4-5 x 10(6) u/m2) was injected subcutaneously daily. Lymphokine-activated killer (LAK) and natural killer (NK) cell activity was measured on days 0 and 8. Twenty-one patients received 76 courses. All primary tumors were controlled by surgery (81%) or angioinfarction. Hematologic toxicity was mild; median nadir of platelets was 117 K/microL and of granulocytes was 1.2 K/microL. Dose-limiting toxicity included mucositis, liver damage, and hypotension. No treatment-related death occurred, and only one patient required intensive-care-unit support. Two patients had an objective response, one of which was a complete response. Increased LAK cell and NK cell activity occurred at all IL-2 dose levels. Simultaneous delivery of IL-2, IFN-alpha, and 5-FU is safe and shows antitumor and biologic activity. 5-FU did not appear to suppress IL-2-induced LAK and NK cell activation. Maximum tolerated dose of the three-drug combination is IL-2, 2 x 10(6) u/m2, 5-FU 600 mg/m2, and IFN-alpha, 4 x 10(6) u/m2.

Seventy-seven patients with metastatic transitional cell carcinoma of the bladder who were unable to receive primary Cisplatin-based therapy or failed primary chemotherapy received one of three sequential 5-Fluorouracil-based salvage regimens: a) 5-Fluorouracil (1000 mg/m2 B.S.A. x 5 days) and Mitomycin-C (14 mg/m2 B.S.A. 6 week intervals), b) 5-Fluorouracil (750 mg/m2 B.S.A. x 5 days) and a-Interferon (5 miu/m2 B.S.A. daily x 5 then 3 times a week (TIW), c) 5-Fluorouracil (500 mg/m2 B.S.A. x 5 days), a-Interferon (5 miu/m2 B.S.A. x 5 days then TIW) and 13-Cis Retinoic Acid in escalating doses daily. Only 1 (6%) of the patients with regimen A responded, whereas 9 (30%) of the patients with regimen B and 8 (27%) in regimen C responded. Although all responses were partial remissions, responses were seen in patients with advanced and initially refractory transitional cell carcinomas. This data reveals that a-Interferon and 5-Fluorouracil is an effective combination in the treatment of metastatic transitional cell carcinoma and worthy of further study.

Purpose: A phase II clinical trial was performed to assess the antitumor activity and toxicity of ketoconazole in combination with doxorubicin (Adriamycin; Adria Laboratories, Columbus, OH) in patients with androgen-independent prostate cancer (AI PCa)., Patients and Methods: Thirty-nine consecutive patients whose disease progressed following castration were treated with oral ketoconazole (1,200 mg) daily and Adriamycin (20 mg/m2 in a 24-hour infusion) once weekly. Antitumor activity was assessed by the level of prostatic-specific antigen (PSA) decline., Results: PSA levels decreased > or = 50% from baseline in 21 (55%; 95% confidence interval, 38% to 71%) of 38 assessable patients. We observed partial responses (PRs) in seven (58%) of 12 patients with measurable soft tissue disease (in the lung, lymph nodes, and liver). Two patients with history of atherosclerotic heart disease had a sudden cardiac death. Serious toxic reactions included grade III to V stomatitis and grade III to IV acral erythema in 11 patients (29%), and grade III to IV anal and urethral mucositis in five patients (13%). Grade III to IV neutropenia occurred in 11 patients (29%). Seventeen patients (45%) required hospitalization for complications. Fifteen patients (39%) developed hypokalemia, and 24 patients (63%) developed clinical adrenal insufficiency., Conclusion: The combination of ketoconazole and Adriamycin has a 55% PSA response rate in patients with AI PCa and is worthy of additional study. This treatment results in frequent adrenal insufficiency. Therefore, future studies should incorporate routine corticosteroid replacement. The cardiac complications caused by this combination should be studied further before it is widely used.

Purpose: The purpose of this phase I trial was to determine the toxicity and maximum-tolerated dose (MTD) of murine monoclonal antibody (Mab) 14G2a (anti-GD2) in cancer patients., Patients and Methods: Following tracer doses of iodine-131-labeled 14G2a to determine tumor uptake, 18 patients with refractory melanoma, neuroblastoma, or osteosarcoma received unlabeled 14G2a at total concentrations of 50, 100, and 200 mg/m2 administered as daily 24-hour infusions for 5 days., Results: The overall sensitivity of external immunoscintigraphy was 64 of 74 known metastases (86%). Toxicity from prolonged infusion of 14G2a consisted of severe generalized pain, hyponatremia, fever, rash, paresthesias, weakness, and chronic refractory postural hypotension (two patients). Toxicity was less severe in pediatric patients. The MTD of Mab was 100 mg/m2. Sixteen of 18 patients developed human antimouse antibodies (HAMA) to 14G2a. Terminal-phase half-life (T1/2) of unlabeled Mab was 6.6 +/- 1.8 hours for patients receiving 50 mg/m2 and 39.5 +/- 13.3 hours at the 100-mg/m2 level. Tumor biopsies from six melanoma patients were positive for GD2 antigen, but only two of six had trace amounts of 14G2a present. Three mixed responses (two melanoma, one osteosarcoma) and two partial responses (PRs; neuroblastoma) were observed., Conclusion: Mab 14G2a has modest antitumor activity at the expense of significant toxicity. Dose-limiting neurologic sequelae may significantly limit phase II studies other than in pediatric patients with neuroblastoma.

To determine the maximally tolerated dose of a ricin A chain-conjugated antimelanoma antibody (XomaZyme-Mel), 20 patients with metastatic melanoma were treated with escalating doses of the murine immunotoxin given as single intravenous infusion over 30 minutes. The starting dose was 0.6 mg/kg and was escalated in five groups to a maximum of 1.6 mg/kg. The maximally tolerated dose was 1.25 mg/kg as three of six patients treated at 1.6 mg/kg developed unacceptable toxicity. The dose-limiting toxicity consisted of profound fatigue, myalgias, and arthralgias. These occurred within 4 days and resolved in 7 to 10 days. Other non-dose-limiting toxicities encountered consisted of hypoalbuminemia, weight gain, peripheral edema, mild hypotension, and flu-like syndrome; the severity of these was also dose related. In addition, two allergic reactions occurred, one severe. There was one durable complete response of 12+ months' duration and one brief mixed response lasting 3 months. We conclude that the maximum tolerated single dose of XomaZyme-Mel is 1.25 mg/kg. Phase I studies evaluating 1.25 mg/kg given in multiple doses at 2- to 4-week intervals and phase II studies to determine the response rate of a single 1.25 mg/kg dose are warranted.

Immunological properties of melanoma TILs before and/or after IL-2-based biotherapies were investigated. TILs harvested before therapies, including those for adoptive transfer, proliferated well in culture with IL-2 and displayed cytotoxicity relatively restricted to autologous tumor cells. In contrast, TILs during or at the end of IL-2 based therapies did not proliferate in culture with IL-2. TILs from tumors even harvested 45 days after the end of IL-2 therapy modestly proliferated in culture with IL-2 and showed MHC-nonrestricted cytotoxicity. The number of live tumor cells that were yielded from melanomas during or at the end of IL-2-based therapies significantly decreased in all nine patients with metastatic melanomas, regardless of their clinical responses (2 PR, 2 MR, 2 SD, and 3 PD). Collectively, these results suggest that current IL-2-based therapies resulted in both transient nonresponsiveness of TILs to IL-2 and transient decrease in the number of live tumour cells in most melanoma patients.

To determine whether recombinant human alpha-interferon (rIFN alpha A) could enhance tumor uptake of an antimelanoma monoclonal antibody (Mab) 96.5 in vivo, groups of nude mice bearing P97 antigen-positive human melanoma subcutaneous xenografts were given i.m. injections of normal saline or rIFN alpha A daily for 10 days. On day 7, mice received either 5 micrograms of 111In-labeled Mab 96.5 or irrelevant 111In-labeled subclass-matched or non-subclass-matched control Mabs. Animals were killed 72 h later and the percent injected dose per gram (%ID/g) in tumor and normal organs was determined. There was a significant (p less than 0.001) increase in 96.5 in tumors of IFN-treated mice compared to saline-treated mice and mice receiving irrelevant Mabs. There was also a significantly increased uptake of 96.5 in blood, heart, lung, kidney, and muscle of IFN-treated vs. control mice (p less than 0.05). This finding was most likely due to increased antigen shedding since significant differences in %ID/g were not observed between IFN-treated and control mice bearing antigen-negative tumors. Furthermore, P97 content in tumor and tissues of IFN-treated mice bearing melanoma xenografts was significantly higher than in mice without tumors. In summary, IFN enhanced targeting of 96.5 via an antigen-specific mechanism. These data confirm and extend previous studies in other tumor systems, and suggest that clinical trials of Mabs plus IFN might be useful in overcoming poor Mab localization that occurs as a result of antigenic heterogeneity in humans.

Twenty patients with metastatic malignant melanoma were studied with 99mTc-labeled monoclonal antibody (MoAb) Fab fragment (NR-Ml-05) reactive with a high molecular weight (Mr 240,000) melanoma associated antigen. Patients received 40 mg unlabeled irrelevant MoAb (NR-2AD-IgG) and 7.5 mg unlabeled NR-Ml-05 (whole IgG) prior to infusion of 10 mg 99mTc-labeled (10-25 mCi) NR-Ml-05 Fab. Unlabeled MoAb were given to block nonspecific and specific binding sites. Gamma camera scans and single photon emission computed tomography were performed at 8 and 24 h postadministration. Of 172 preexisting lesions, 136 were imaged for a sensitivity of detection of 79%. Imaging was site and size dependent with the greatest sensitivity for liver lesions (100%) and the least for bowel (0%). Six sites (2 skin, 1 lung, 3 liver) were detected by single photon emission computed tomography that were missed on routine planar images. Forty-one additional unconfirmed sites were seen. Of these, 7 (17%) have been confirmed as tumor after a median follow-up time of 6 months. False positive scans included scar tissue, areas of chronic inflammation, an infected femoral aneurysm, and septic emboli. Nonspecific uptake of radioactivity occurred in kidney, gallbladder, bowel, thyroid, and myocardium. Human anti-mouse antibodies were detected in up to 69% of patients. In summary, radioimaging with 99mTc-NR-Ml-05 is a sensitive test, especially for detecting liver lesions. It is safe, simple to administer, and convenient for the patient. Biodistribution and imaging sensitivity differ significantly from studies in which 111In-labeled anti-melanoma MoAb have been used.

In an attempt to improve the therapeutic index of recombinant interleukin-2 (rIL-2) by generating or activating lymphokine-activated killer (LAK) cells and tumor-infiltrating lymphocytes (TIL) regionally and/or in situ, we randomly assigned 28 patients with liver metastases to receive rIL-2 by continuous infusion for 5 days via either the splenic artery or the hepatic artery. Clinically significant and lasting tumor regression was observed only in two of 28 patients (7%), one in each of the two treatment arms. The maximum-tolerated daily dosage of rIL-2 was 3 x 10(6) U/m2; beyond this dosage, toxicity was excessive. Peripheral LAK cell activity measured in vitro and clinical tumor regression did not correlate. This observation, coupled with the equal distribution of regressions between the two treatment arms, raises the possibility that tumor regression, rare though it may be in response to rIL-2 administration, is largely mediated by TIL activation and not by LAK cell generation.

The clinical data that have been accumulated so far suggests a significant influence of IL-2 dose and schedule on the immunobiological effects and clinical toxicities observed with this cytokine. Consequently, the series of Phase I and Phase II clinical trials conducted at the University of Texas M. D. Anderson Cancer Center in patients with advanced malignant melanoma investigating the use of IL-2 in combination with other cytokines, monoclonal antibodies, or ex vivo activated effector cells have used a common dose and schedule of IL-2 administration for which abundant immunobiological information already exists. This approach allows cross-trial comparison of experience with toxicities, immunobiological observations and clinical activity by a group of investigators within a single institution, and more rapid and valid evolution towards combination biological therapy, which preclinical data suggest will have greater activity than single agent therapy.