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S Litwin

Publications and source records attributed to S Litwin.

At least 19 recordsLinked to original sources
PubMed1992

Phase II study of estramustine and vinblastine, two microtubule inhibitors, in hormone-refractory prostate cancer.

PURPOSE: Estramustine phosphate (EMP) and vinblastine are two microtubule inhibitors with distinct molecular targets and at least additive antimicrotubule effects in vitro. Their modest single-agent activities in hormone-refractory prostate cancer, nonoverlapping toxicities, and lack of cross-resistance prompted a phase II trial in hormone-refractory prostate cancer. PATIENTS AND METHODS: Thirty-six assessable patients at the Fox Chase Cancer Center and seven Fox Chase Cancer Center Network institutions were treated with oral EMP 600 mg/m2 on days 1 to 42 and vinblastine 4 mg/m2 intravenously (IV) once a week for 6 weeks. Courses were repeated every 8 weeks. Response assessment was based on a change in serum prostate-specific antigen (PSA) levels and was correlated with change in pain scores. RESULTS: PSA decreased from baseline by at least 50% in 22 patients (61.1%) and by > or = 75% in eight patients (22.2%). A 50% or more decrease in PSA on three successive 2-week measurements together with an improved or stable pain score, performance status, and measurable soft tissue disease (if present) was required for a partial response (PR), which occurred in 11 patients for an overall response rate of 30.5% (95% confidence interval, 15.6% to 45.6%). In seven patients with measurable nonosseous disease, there was one PR (14%) and one minor response (MR). In 28 patients with assessable pain, major pain responses occurred in 12 (42.9%). PSA response (> or = 50% decrease times three measurements) was predictive of major pain response with a 93.7% specificity, a 50% sensitivity, and a positive predictive value of 85.7%. CONCLUSION: We conclude that EMP and vinblastine is an active combination in hormone-refractory prostate cancer.

Aged↗
PubMed1992

Effects of formaldehyde on xenotransplanted human respiratory epithelium.

A laboratory animal model that permits the exposure of xenotransplanted human respiratory epithelium to formaldehyde was used to study the effects of formaldehyde alone or in combination with the ultimate carcinogenic metabolite of benzo[a]pyrene, benzo[a]pyrene diol epoxide. Epithelial cells obtained from autopsies of full-term human fetuses or infants less than one year old were isolated, amplified in primary cultures, and then inoculated into rat tracheas from which the epithelial layer had been removed. These tracheas then were sealed and transplanted subcutaneously into irradiated athymic nude mice. Four weeks after transplantation, the tracheal lumen was completely covered by epithelium, most of which was of the mucociliary respiratory type. At this stage, tracheal transplants containing tracheobronchial epithelium from 20 different human infant donors were exposed to silastic devices containing 0, 0.5, 1, or 2 mg of formaldehyde. The tracheal transplants were examined histologically 2, 4, 8, or 16 weeks after transplantation. Before being killed, all animals were injected with a single pulse of tritiated thymidine. Important epithelial alterations were seen in the transplants treated with formaldehyde, with a maximum effect visible two weeks after exposure. In most cases, the highest dose of 2 mg produced numerous areas of epithelial erosion and inflammation; however, this effect was not as evident with the lower doses. All doses produced areas of hyperplastic epithelium alternating with areas of atrophic epithelium. Although the differences in predominance of different types of epithelium were not clearly dependent on dose, the labeling index showed dose dependence between two and four weeks after the initiation of exposure. The maximum mean labeling index was three to four times higher than normal, although in some focal hyperplastic-metaplastic lesions the labeling index increased up to 20 times. These studies show that formaldehyde, although toxic at higher doses, is able to elicit at lower doses a proliferative response of the human infant tracheobronchial epithelium that is not preceded by a massive toxic effect. Similar studies were performed using xenotransplanted human adult nasal respiratory epithelium (Study 2). The response pattern was very similar to that of the xenotransplanted human tracheobronchial epithelium from human infants (Study 1). In Study 3, using cells obtained from 11 human infant tracheobronchial epithelia, the formaldehyde applied simultaneously or sequentially with benzo[a]pyrene diol epoxide did not induce epithelial alterations different from those observed with formaldehyde treatments alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Phase I study of thiotepa in combination with the glutathione transferase inhibitor ethacrynic acid.

The glutathione transferases comprise a family of isoenzymes, one or more of which are involved in the conjugation of alkylating agents to glutathione (GSH). Increased GSH transferase activity has been shown to underlie acquired resistance to several alkylating agents. Ethacrynic acid inhibits the isoenzymes of GSH transferase with 50% inhibitory concentration values ranging from 0.3 to 6.0 microM and has been shown to restore sensitivity to alkylating agents in drug-resistant animal tumor models. We entered 27 previously treated patients with advanced cancer on a study of ethacrynic acid (25 to 75 mg/m2 p.o. every 6 h for 3 doses) and thiotepa (30 to 55 mg/m2 i.v. 1 h after the second dose of ethacrynic acid). The major toxicity of ethacrynic acid was diuresis, which was observed at every dose level; in addition, severe metabolic abnormalities occurred at 75 mg/m2. At 50 mg/m2, the diuretic effects were manageable. Myelosuppression was the most important effect of the combination. Two of seven courses of ethacrynic acid, 50 mg/m2, and thiotepa, 55 mg/m2, were associated with grade 3 or 4 neutropenia and/or thrombocytopenia. Nausea/vomiting greater than or equal to grade 2 was observed in 16% of courses. GSH transferase activity was assayed spectrophotometrically in the peripheral mononuclear cells of all patients. At each dose level, activity decreased following ethacrynic acid administration, with recovery by 6 h. Administration of ethacrynic acid, 50 mg/m2, resulted in a mean nadir of transferase activity of 37% of control. The pharmacokinetics of thiotepa and its principal metabolite TEPA were studied in 23 patients. The plasma disappearance of thiotepa fit a two-compartment open model with a terminal half-life of approximately 2 h. Plasma TEPA levels peaked at a mean of 2.16 h following thiotepa administration. The harmonic mean terminal half-life of TEPA was 10.4 h, and the TEPA area under the curve (AUC) did not increase with increasing thiotepa dose. The AUC of thiotepa was approximately twice, and the clearance about one-half, of the values obtained in a previous study of single agent thiotepa. The AUC of TEPA was lower than that previously observed. The data suggest that ethacrynic acid inhibits enzymes involved in the metabolic disposition of thiotepa, including its oxidative desulfuration to TEPA. The severity of the platelet toxicity was correlated with the AUC of thiotepa, but not with that of TEPA. This combination of thiotepa and ethacrynic acid will be tested further in Phase II trials.

Adult↗
PubMed1991

Phase I evaluation of combination therapy with interleukin 2 and gamma-interferon.

Recombinant interleukin 2 (IL-2) is a potent inducer of lymphokine-activated killer (LAK) activity directed against autologous and allogeneic tumors; these effects are mediated by CD3-negative, CD56-positive, and CD16-positive lymphocytes. Although IL-2 therapy has been associated with clinical responses, particularly in patients with renal cell carcinoma and melanoma, these responses have occurred with high, toxic doses of this cytokine. Since gamma-interferon (IFN-gamma) potentiates LAK activity in vitro and in animal models, we initiated a dose-escalating Phase I trial of IFN-gamma and IL-2 in patients with advanced cancer. Patients were treated three times weekly (Monday, Wednesday, and Friday) for 6 weeks with bolus injections of IL-2; each dose was preceded 2 h earlier by a s.c. injection of IFN-gamma. Patients were treated with IFN-gamma at 0.01, 0.05, 0.1, or 0.25 mg/m2/dose. At each IFN-gamma dose, cohorts of at least three patients were treated with IL-2 at 1, 2.5, 5.0, or 7.5 x 10(6) Cetus units/m2 dose. Patients with clinical responses continued therapy three times weekly, while those with stable disease at 6 weeks were then treated twice weekly. A total of 41 patients were treated, all with Eastern Cooperative Oncology Group performance status 0 or 1. All patients were evaluable for toxicity. Dose-limiting toxicities were cumulative fatigue and constitutional symptoms. One documented transmural myocardial infarct occurred. The maximally tolerated dose combination, based on analysis of IL-2 dose intensity, was 0.1 mg IFN-gamma/m2 and 7.5 x 10(6) Cetus units IL-2/m2 per dose. Two partial responses and two minor responses were observed. Treatment was not associated with dose-associated changes in peripheral blood lymphocyte phenotype, but there was a trend favoring IFN-gamma dose-associated rises in IL-2 induction of natural killer and LAK activity by treated patients' lymphocytes. Analysis of the cumulative effects of therapy on induction of natural killer and LAK activity by measurement of the median area under the curve of activation showed clear evidence of IFN-gamma and IL-2 dose-associated changes. The IL-2 dose effects on cell lysis were monotone, while the optimal IFN-gamma dose appeared to be 0.1 mg/m2/dose, with a bell-shaped dose-response curve described previously for other effects of this cytokine. Using this novel statistical method of evaluating the biological effects of treatment, the optimal biological dose was identical to the maximally tolerated dose.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Phase I/pharmacokinetic reevaluation of thioTEPA.

Because the initial evaluation of N,N',N''-triethylenethiophosphoramide (thioTEPA) preceded the standardized approach to the Phase I trials, uncertainty surrounds the recommended dose. Since it has recently been demonstrated that an almost 100-fold increase in dose can be administered in bone marrow transplant regimens, we conducted a Phase I reevaluation of thioTEPA. ThioTEPA was administered i.v. in 50 ml 5% dextrose in water over 10 min. Twenty-seven patients were entered at doses ranging from 30 to 75 mg/m2. The major toxic effect was myelosuppression; thrombocytopenia greater than or equal to grade 3 occurred in four of seven patients, and leukopenia greater than or equal to grade 3 in two of seven patients at 75 mg/m2. Among eight patients at 65 mg/m2 only two had greater than or equal to grade 3 myelosuppression making this the recommended new phase II dose for the majority of patients. Moderate (grade 2) easily controlled nausea and vomiting was the only other major side effect. There was no alopecia or mucosal or neurological toxicity. Three partial remissions were observed among nine previously treated ovarian cancer patients. Plasma concentrations of thioTEPA and its major active metabolite triethylenephosphoramide (TEPA) were measured by gas chromatography. The half-life of thioTEPA ranged from 51.6 to 211.8 min, and its pharmacokinetics was dose dependent; total body thioTEPA clearance decreased with increasing dose. The half-life of TEPA was considerably longer than that of the parent compound (3.0 to 21.1 h); as a result, the area under the plasma concentration-time curve (AUC) of TEPA was severalfold greater than that of the parent compound. The ratio of TEPA AUC to thioTEPA AUC decreased with increasing dose, suggesting that formation of TEPA is a saturable step in elimination. The AUC and total body clearance of thioTEPA, but not of TEPA, were closely correlated with neutrophil but not platelet toxicity.

Dose-Response Relationship, Drug↗
PubMed1991

Pharmacokinetic study of trimetrexate in combination with cisplatin.

The addition of the antifol methotrexate to cisplatin (DDP) produces supraadditive antitumor effects in preclinical studies, but in the clinic this combination of two nephrotoxic drugs is limited by excessive toxicity. Trimetrexate (TMTX) is a second generation antifol with predominantly nonrenal elimination and antitumor activity superior to that of methotrexate in preclinical models. In early clinical trials TMTX demonstrated promising activity in non-small cell lung cancer, and nephrotoxicity was rare. We performed a Phase I clinical and pharmacological study of TMTX (escalating doses) in combination with DDP (20 mg/m2), both administered i.v. for 5 consecutive days, every 4 wk. The pharmacokinetics of TMTX was determined in 15 patients after administration of the single agent (baseline study) and following the Day 1 and Day 5 doses in the TMTX-DDP combination. The recommended Phase II single-agent dose of TMTX on this schedule, 8 mg/m2, did not produce excessive toxicity when given concurrently with DDP. Significant drug-related nephrotoxicity was not observed, even in patients receiving multiple courses of TMTX-DDP. The mean renal clearance of TMTX increased 1.4-fold and 2.8-fold over baseline on Days 1 and 5, respectively, of TMTX-DDP. Urinary flow was similarly greater on days of TMTX-DDP treatment. The nonrenal clearance of TMTX was unaffected by concurrent DDP. The steady-state volume of distribution, Vdss, and terminal elimination half-life were significantly greater on Day 5 of TMTX-DDP compared to baseline. The plasma protein-binding of TMTX in vitro was not altered by DDP, and the disappearance of ultrafilterable DDP from normal plasma in vitro was unchanged by TMTX. Although a protein-binding interaction of TMTX and DDP was not detected in normal plasma in vitro, the changes in renal clearance, Vdss, and the terminal half-life were consistent with a greater fraction of unbound TMTX in plasma following Day 5 of TMTX-DDP. Effects of DDP on the binding of TMTX to extravascular tissue components, or on the renal handling of TMTX, cannot be excluded. The increase in TMTX renal clearance correlated with increased urinary flow, which may improve the therapeutic index of TMTX as both an antineoplastic and antiparasitic agent.

Antineoplastic Agents↗
PubMed1991

Somatic hypermutation of the JC intron is markedly reduced in unrearranged kappa and H alleles and is unevenly distributed in rearranged alleles.

Somatic hypermutation of the Ig genes occurs in rearranged V(D)J and its flanking sequences after Ag stimulation. Even though C regions and unrearranged V segments have been found to lack mutations, it is not known whether the mutational mechanism can be active in unrearranged J segments and their flanking regions. By polymerase chain reaction and direct sequencing of the 500 bp at the 5' end of the JC intron of hybridoma DNA derived from splenic B cells, we show that the frequency of mutations in unrearranged J regions of kappa and H chain genes is 0/7849 bp (upper 95% confidence interval, less than 0.00038) and 1/3209 bp (upper 95% confidence interval, less than 0.0015), respectively. The frequency (f) for the same region of rearranged kappa and H chain genes was 29/9380 bp (95% confidence, 0.0021 less than f less than 0.0044) and 16/2750 bp (95% confidence, 0.0033 less than f less than 0.0094), respectively. The significantly higher frequency of mutations in the rearranged alleles indicates that rearrangement is needed to effect full activation of the mutational mechanism. The data also show that mutations occur predominantly in the 5'-most 250 bp of the JC kappa intron. Statistical analysis of the distribution of mutations within the 5'-most 521 bp of the JC kappa intron reveals significant deviation (p = 0.000085) from a theoretically determined uniform distribution, indicating that mutations are not evenly distributed within this region.

Alleles↗
PubMed1991

Phase II study of weekly 5-fluorouracil, cisplatin and vinblastine in advanced non-small cell lung cancer.

The scheduling of chemotherapeutic agents may be important in optimising their antitumour actions. This has been explored in non-Hodgkin lymphoma, osteogenic sarcoma and bladder cancer with improved results using intensive, weekly dosing schemas. We began a phase II study of cisplatin, 5-fluorouracil and vinblastine in non-small cell lung cancer (NSCLC) on a weekly schedule. 38 patients with advanced or metastatic NSCLC were entered; 32 are evaluable for response. 11 patients were treated with 5-fluorouracil 1.5 g/m2 and vinblastine 4 mg/m2 by 24-h continuous infusion, and cisplatin 30 mg/m2 over 30 min, 6-8 h after the start of the infusion. Because of prohibitive myelotoxicity, the next 27 patients received 5-fluorouracil 1.2 g/m2 and vinblastine 3 mg/m2. None had had prior chemotherapy while 6 had had previous radiation therapy. Myelosuppression was the predominant toxic effect. Other side-effects included neuropathy, diarrhoea, mucositis, nausea and vomiting. 32 patients are evaluable for response: there have been 14 partial remissions (44%). Responses have occurred chiefly in lung and lymph nodes. The median survival on this study is 7 months, and responders did not live longer than non-responders. While this regimen is well tolerated by the majority of patients and has a response rate comparable to other active regimens identified in single institution studies, survival does not appear to be enhanced. We conclude that the schedule manipulation described here does not enhance the therapeutic index of these drugs in NSCLC.

Adult↗
PubMed1991

Risk factors for immediate prosthetic postmastectomy reconstruction.

The charts of 44 women who underwent 47 immediate postmastectomy prosthetic breast reconstructions (IPMPBR) with subpectoral prostheses (long-term implant, long-term expandable implant or tissue expanders followed by long-term prosthetic placement) were retrospectively reviewed. Follow-up was from 3 to 49 months (median 18 months). Patient ages ranged from 31 to 77 years (median 42) but 82 per cent were under 60 years old. Indications for mastectomy were infiltrating cancer in 30 patients, intraductal cancer in 11, lobular carcinoma in situ in two and prophylaxis in one. There were 11 patients with pathologic Stage I, 15 with Stage II, three with Stage III and one with Stage IV breast cancer. Adjuvant chemotherapy (CTX) was given to 17 women, adjuvant hormonal treatment to nine, and radiation therapy (RT) to five. One patient had prosthesis extrusion and removal. Two patients had late periprosthetic infections (PPI) with consequent prosthesis removal. CTX did not have a significant association with PPI (two of 14 with CTX vs 0 of 29 without, P = 0.1). However, fill port migrations, prosthesis deflations, and greater than 1 complication were significantly associated with these infections (two of three vs 0 of 38, P = 0.004; two of two vs 0 of 45, P = 0.001; two of four vs 0 of 43, P = 0.006). Skin flap cellulitis and postoperative seroma were also associated with PPI (P less than 0.003 and less than 0.006, respectively). These factors were all also significantly associated with involuntary prosthesis loss (n = 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Properties of ornithine decarboxylase in human colorectal adenocarcinomas.

Ornithine decarboxylase (ODC) activity was measured in colon adenocarcinomas and adjacent normal-appearing colon mucosa from a total of 40 patients undergoing surgical resections. The enzyme activity was measured in the presence and absence of GTP, since recent work has demonstrated a GTP-activatable form of ODC in some murine and human tumors. In general, ODC specific activity was higher in adenocarcinomas than in adjacent normal-appearing mucosa. Of greater interest, however, was the finding that 13 of 40 tumors and 3 of 40 mucosae contained a GTP-activatable form of ODC. These are minimal estimates of the proportion of tissues positive for this enzyme form, since a multiple sampling protocol indicated that expression of a GTP-activatable ODC was not uniform throughout a given tumor. Chromatographic analyses of tumor extracts revealed the presence in some tumors of multiple size forms of ODC, only some of which were activated by GTP. Enzyme kinetic data indicated that the multiple forms of ODC can have different affinities for L-ornithine and that GTP can "normalize" the aberrant kinetic properties of these forms. While there was no statistically significant correlation of the presence of a GTP-activatable ODC with stage of disease, analysis of our data revealed a positive association of a GTP-activatable ODC with tumor site; a much higher percentage of tumors of the cecum contained this ODC isoform than tumors of other colonic segments (64% versus less than or equal to 25% for other sites). These results demonstrate (a) the presence of a functionally distinct form of ODC in some human colon adenocarcinomas and (b) a distinct regional distribution of this ODC form within the colon. We suggest this alteration in a key enzyme in the growth-associated pathway of polyamine biosynthesis may play a role in colon tumor progression.

Adenocarcinoma↗
PubMed1990

Phase II study of biochemical modulation of fluorouracil by low-dose PALA in patients with colorectal cancer.

Higher response rates in colorectal cancer have been observed with regimens that increase the cytotoxicity of fluorouracil (5-FU) by altering the biochemical milieu at its site(s) of action. Phosphonacetyl-L-aspartate (PALA), which inhibits aspartate transcarbamylase and depletes uridine nucleotide pools in vitro and in vivo, selectively potentiates the antitumor activity of 5-FU in preclinical models. In a phase I/II study in patients with advanced colorectal cancer, PALA 250 mg/m2 was given on day 1, followed 24 hours later by 5-FU 2,600 mg/m2 by 24-hour infusion repeated weekly. Through the use of subcutaneous ports and portable infusion pumps, all patients were treated outside the hospital setting. Thirty-nine patients without prior chemotherapy received 884 courses of treatment. The primary site was colon in 31, rectum in eight. Toxicity was generally mild to moderate except among four patients who were escalated to 5-FU 3,250 mg/m2: two developed severe gastrointestinal toxicity and myelosuppression. Among the remaining 35 patients, gastrointestinal and neurologic toxicities predominated, but usually did not develop until the third or fourth month of treatment. Two patients were inevaluable for response. Among the 37 evaluable patients there were three complete and 13 partial remissions for a total response rate of 43% (95% confidence interval [Cl], 27% to 59%). The median duration of response was 5 months (range, 1.5 to 15 months). The projected mean survival is in excess of 17 months. This high response rate is comparable to the best results obtained with other means of modulation of 5-FU. Demonstration of a survival benefit will require larger phase III studies.

Adenocarcinoma↗
PubMed1989

Relationship of variable region genes expressed by a human B cell lymphoma secreting pathologic anti-Pr2 erythrocyte autoantibodies.

To study the biology of cold agglutinin disease we previously established EBV-transformed B cell clones isolated from a patient with splenic lymphoma of an early plasmacytic cell type and immune hemolysis due to an anti-Pr2 cold agglutinin. These clones had an aberrant chromosomal marker identical to the patient's B cell lymphoma and each secreted IgMk anti-Pr2 similar to the pathologic autoantibody in the serum of the patient. In this study, we have further investigated the Pr2-specific autoimmune response through nucleotide sequencing of VH and VL region genes. We have shown that the seven clones share the same VDJ/VJ gene segments and junctional elements confirming their clonal origin. The VH sequences were 88% homologous to a VHI germline gene while the VL sequences were 97% homologous to a VkIII germline gene. Only 4 somatic mutations (3 silent and 1 conservative) were found in greater than 5,000 bp sequenced, suggesting that a low mutation rate existed. Based on a tumor mass of 10(12) cells and a minimum of 40 divisions, we estimated the somatic mutation rate to be 4.45 x 10(-5) m/bp/d. This somatic mutation rate is similar to those estimated for acute lymphocytic leukemia (pre-B cell) and chronic lymphocytic leukemia (intermediate B cell), but significantly lower than the mutation frequency in follicular lymphomas (activated B cell). We propose that the difference in somatic mutation frequency of a B cell tumor may be related to the stage of B cell differentiation. In addition, the low mutation frequency observed in the Pr2-specific B cell tumor may also reflect, in part, selection by autoantigen to conserve sIg structure and specificity.

Agglutinins↗
PubMed1989

Surface immunoglobulin light chain restriction in B-cell non-Hodgkin's malignant lymphomas.

Twenty-four control cases of reactive follicular hyperplasia (RFH) and 28 cases of B-cell non-Hodgkin's malignant lymphoma (ML) were evaluated for surface immunoglobulin (sIg) light chain expression with flow cytometry. Because there was no significant difference between the distribution of the ML kappa/lambda ratios for which kappa/lambda greater than 1 compared with those ML lambda/kappa ratios for which lambda/kappa greater than 1 using the Kolmogorov-Smirnov statistic, the authors treated kappa/lambda and lambda/kappa data symmetrically. By transforming all kappa/lambda ratios to maximum ratios, that is, Rmax = max (kappa/lambda, lambda/kappa), so that all resulting ratios were at least one, the authors defined a new statistic for evaluating sIg light chain restriction. There was a highly significant difference for equality of distribution of the data using the Mann-Whitney test (P less than 0.0001). By choosing cut-points based on the Rmax statistic, the authors were able to separate the RFH and ML cases with sensitivity = 0.96 +/- 0.07 (95% confidence) and with specificity = 0.91 +/- 0.11 (95% confidence). These point estimates of sensitivity and specificity appear to be promising for the clinical utility of the Rmax statistic, even for cases of B-cell ML with discordantly low expression of sIg light chains. The Rmax statistic will facilitate the comparison of data between different laboratories because it does not require prior assignment of cut-points and can be made using a simple nonparametric test.

Adolescent↗
PubMed1989

Effects of formaldehyde on normal xenotransplanted human tracheobronchial epithelium.

Epithelial cells obtained from autopsies of full-term fetuses or infants less than 1 year old were isolated, amplified in primary cultures and inoculated in deepithelialized rat tracheas. These tracheas were then sealed and transplanted subcutaneously into irradiated athymic nude mice. Four weeks after transplantation the tracheal lumen was completely covered by epithelium, most of which was of mucociliary respiratory type. At this stage, tracheal transplants containing tracheobronchial epithelium from 20 different donors were exposed to silastic devices containing 0, 0.5, 1 and 2 mg paraformaldehyde. The tracheal transplants were examined histologically at 2, 4, 8, and 16 weeks after transplantation. Before sacrifice, all animals were injected with a single pulse of tritiated thymidine. Important epithelial alterations could be seen in the formaldehyde treated transplants with a maximum effect visible at 2 weeks after exposure. The highest dose of 2 mg produced, in most cases, numerous areas of epithelial erosion and inflammation whereas this effect was not as evident with the lower doses. All doses produced areas of hyperplastic epithelium alternating with areas of pleomorphic-atrophic epithelium. Although the differences in predominance of different types of epithelium was not clearly dose-dependent, the labeling index (LI) showed dose dependence between 2 and 4 weeks after initiation of exposure. The maximum mean LI was three to four times higher than normal, although in some focal hyperplastic-metaplastic lesions the LI was increased up to 20 times. These studies show that formaldehyde, although toxic at higher doses, is able to elicit at lower doses a proliferative response of the human respiratory epithelium that is not preceded by a massive toxic effect. This response is similar, although less intense than that of the rat respiratory epithelium in which formaldehyde proved to be a carcinogen.

Animals↗
PubMed1988

A phase I study of recombinant interleukin 2 plus recombinant beta-interferon.

Interleukin 2 (IL-2) therapies have antitumor activities against several neoplasms. In vitro these activities are enhanced by beta-interferon (IFN-beta). Therefore, we initiated a Phase I trial with a combination of IL-2 and IFN-beta three times weekly. The IFN-beta was administered i.v. Initially, the IL-2 was administered s.c. However, neutralizing antibody to the IL-2 developed in five patients, and the route of administration of the IL-2 was changed to i.v. Forty-seven patients were entered on the study. The maximum tolerated doses for the combination given i.v. were 5 x 10(6) units/m2 of IL-2 and 10 x 10(6) units/m2 of IFN-beta. Dose-limiting toxicities were profound fatigue/decreased performance status, anorexia/weight loss, depression, and arthralgias. Hypotension, exfoliative skin rash, thrombocytopenia, diarrhea, temperature greater than 40.6 degrees C, and peripheral edema were rarely dose limiting. Thirty-two patients were evaluable for response. After 4 weeks of treatment, 21 patients had stable disease, three patients had a minor response, and one patient had a partial response. Significant lymphokine-activated killer cell (LAK) activity was seen in seven patients (22%) and required 5 x 10(6) units/m2 of IL-2. Those who had progressive disease had significantly less LAK activity than those with either stable disease or a response. This therapy also induced more than 60 units/ml of endogenous gamma-interferon 4 h after the i.v. IL-2 administration. This study demonstrates that (a) intermittent i.v. bolus IL-2 therapy can generate LAK activity, (b) LAK activity may be associated with an antitumor response, (c) significant levels of gamma-interferon are induced by this therapy, and (d) IL-2 and IFN-beta given three times weekly i.v. is both tolerable and biologically active. The recommended Phase II dose is 5 x 10(6) units/m2 of IL-2 plus 6 x 10(6) units/m2 of IFN-beta.

Adult↗
PubMed1988

Antibody delivery and effector cell activation in a phase II trial of recombinant gamma-interferon and the murine monoclonal antibody CO17-1A in advanced colorectal carcinoma.

Murine monoclonal antibodies of the immunoglobulin G2a isotype interact with human effector cells to mediate antibody-dependent cellular cytotoxicity (ADCC) directed against malignant cells which express antigens recognized by these antibodies. gamma-Interferon enhances these effects in vitro. In a Phase I trial of murine monoclonal antibody CO17-1A and recombinant gamma-interferon (rIFN-gamma), we demonstrated that low doses of rIFN-gamma were superior to high doses in augmenting ADCC mediated by treated patients' monocytes. These results formed the basis for a Phase II trial of CO17-1A combined with low dose rIFN-gamma. Nineteen patients with metastatic colorectal carcinoma were treated with four consecutive daily infusions of 1.0 X 10(6) IU/m2 rIFN-gamma, with 150 mg of CO17-1A administered on days 2, 3, and 4. Therapy was tolerated well. Peripheral blood mononuclear cells were purified from patient samples obtained at baseline and at 1, 4, or 24 h following the start of the first rIFN-gamma infusion and were tested for their ability to lyse 111In-labeled cells of the SW1116 colorectal line. Enhancement of monocyte ADCC was seen by 24 h, while lymphocyte ADCC and natural killer activity directed against K562 cells were enhanced to a lesser extent. Nonspecific lysis of SW1116 cells by effectors was not seen at the time points examined. While CO17-1A antigen expression was observed in most biopsies, 131I-labeled CO17-1A imaged positively in less than one-half of the organs known to harbor metastases, and therapeutic antibody delivery was not always demonstrated by immunoperoxidase staining techniques of tissue obtained following therapy. In antigen-positive lesions, tissue pO2 levels appear to identify lesions which would image positively. No objective responses were seen. Our findings suggest that prolonged therapy with low doses of rIFN-gamma potentiates ADCC but that physiological obstacles to therapeutic antibody delivery are significant. In order to evaluate the validity of this therapeutic approach, measures to enhance antibody delivery are needed, starting with systematic evaluations of therapy with escalating doses of CO17-1A combined with low dose rIFN-gamma therapy.

Adult↗
PubMed1988

Noncorrelation of the expression of the c-myc oncogene in colorectal carcinoma with recurrence of disease or patient survival.

Our previous work has shown that 26 of 38 cases (68.4%) of primary adenocarcinoma of the colon exhibited significantly elevated levels of c-myc RNA compared to normal colonic mucosa (M. D. Erisman, P. G. Rothberg, R. E. Diehl, C. C. Morse, J. M. Spandorfer, and S. M. Astrin. Mol. Cell. Biol., 5: 1969-1976, 1985; P. G. Rothberg, J. M. Spandorfer, M. D. Erisman, R. N. Staroscik, H. F. Sears, R. O. Petersen, and S. M. Astrin. Br. J. Cancer, 52: 629-632, 1985). In this study, we have compared those levels of expression to the clinical profiles of the affected individuals in an effort to define useful correlates, especially with regard to recurrence of disease and patient survival. Log-rank comparisons of recurrence curves for the entire patient population, for those patients with low levels of c-myc RNA in resected tumor tissue, and for those patients with significantly elevated levels of RNA show no statistically significant differences. Similarly, no statistically significant difference was observed between the high- and low-myc RNA groups with respect to their survival during the postoperative period of observation (median, 25 months). Consequently, the levels of c-myc gene expression observed in primary tumor tissue did not help to define those individuals at higher or lower risk for recurrence of disease and did not point to the likelihood of increased or decreased survival in individuals undergoing surgery for adenocarcinoma of the colon.

Adenocarcinoma↗