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D R Vlock

Publications and source records attributed to D R Vlock.

At least 19 recordsLinked to original sources
PubMed2001

Phase III comparison of high-dose paclitaxel + cisplatin + granulocyte colony-stimulating factor versus low-dose paclitaxel + cisplatin in advanced head and neck cancer: Eastern Cooperative Oncology Group Study E1393.

PURPOSE: To determine dose-response effects and the activity of paclitaxel combined with cisplatin in patients with incurable squamous cell carcinoma of the head and neck. PATIENTS AND METHODS: Two hundred ten patients with locally advanced, recurrent, or metastatic disease were randomly placed in either Arm A, paclitaxel 200 mg/m(2) (24-hour infusion) + cisplatin 75mg/m(2) + granulocyte colony-stimulating factor, or Arm B, paclitaxel 135 mg/m(2) (24-hour infusion) + cisplatin 75 mg/m(2). Cycles were repeated every 3 weeks until progression or a total of 12 cycles for complete responses. Primary outcomes were event-free and overall survival. RESULTS: No significant differences in outcomes were observed between the high- and low-dose paclitaxel regimens. The estimated median survival was 7.3 months (95% confidence interval, 6.0 to 8.6). The 1-year survival rate was 29%, and event-free survival was 4.0 months. The objective response rate (complete response plus partial response) was 35% for the high-dose patients and 36% for the low-dose patients. Myelosuppression was the most frequent toxicity: grade 3 or 4 granulocytopenia, 70% of patients in Arm A and 78% in Arm B; febrile neutropenia, 27% of patients in Arm A and 39% in Arm B. Grade 5 toxicities occurred in 22 patients (10.5%). Treatment was terminated early in 31% because of excessive toxicity or patient refusal. CONCLUSION: This phase III multicenter trial showed (1) no advantage for high-dose paclitaxel and (2) excessive hematologic toxicity associated with both regimens. Therefore, neither of the paclitaxel regimens evaluated in this trial can be recommended.

Adult↗
PubMed2000

Analysis of therapeutic and immunologic effects of R(24) anti-GD3 monoclonal antibody in 37 patients with metastatic melanoma.

BACKGROUND: Antitumor effects of antibodies against ganglioside antigens of melanoma have been reported, but neither optimal doses nor mechanisms have been established. METHODS: This Phase IB trial of the murine immunoglobulin IgG(3) monoclonal antibody R(24) against disialoganglioside GD3 was conducted with 37 patients to define better the dose-response relation and mechanism of action of R(24) in patients with metastatic melanoma. RESULTS: Dose-limiting toxicity consisted of a pulmonary capillary leak syndrome in 3 of 5 patients in the 80 mg/M(2)/day dosage tier. Serial blood and tumor biopsy samples were obtained prior to therapy and on Days 5, 9, and 22 following R(24) infusion. Tumor biopsy-infiltrating lymphocytes were enumerated in peritumoral, endotumoral, and perivascular compartments: endotumoral CD4(+) and CD8(+) T cells and HLA-DR(+) T cells increased over time on R(24) antibody. Endotumoral CD4 lymphoid infiltrate activation (DR expression) and antibody-dependent cytotoxicity were the greatest in the one patient who achieved a complete response. CONCLUSIONS: Clinical response was associated with depression in natural killer (CD56(+) and CD56(+)DR(+)) blood cells (P = 0.03) and was associated with R(24) dosage (P = 0.01). A complete response that lasted 2 years and a partial response that lasted 2 months occurred at a dose of 1 mg/M(2)/day. The limited number of clinical responses observed in this trial hampered the correlation of antitumor and immune parameters but provided a rational foundation for the future evaluation of antiganglioside antibodies.

Adult↗
PubMed1997

Biologic response modulation by tumor necrosis factor alpha (TNF alpha) in a phase Ib trial in cancer patients.

During a phase I study of recombinant human tumor necrosis factor (TNF) in cancer patients, serial immune studies were performed and analyzed for effects of TNF. The TNF (specific activity 9.6 x 10(6) U/mg protein, < 5.0 endotoxin units/mg protein) was given over 2 h intravenously on days 1, 8-12, 29-33, 50-54, and 71-75 at doses of 40, 80, 160, 200, and 240 micrograms/m2. Immunologic testing was performed before therapy three times and subsequently on days 2, 8, 10, 12, 29, 33, 50, 54, 71, 75, and off-study two times. Immune parameters evaluated included cytotoxicity [natural killer (NK), spontaneous lymphokine activated killer cells (LAK), LAK, and monocyte], cytokine production [spontaneous and stimulated interferon (IFN)-gamma and interleukin (IL)-2], superoxide production [resting and stimulated polymorphonuclear (PMN) and mononuclear cells (MNC)], and phenotype of peripheral blood lymphocyte subsets (CD3, CD4, CD8, CD16, CD56, CD19). Data were analyzed for long-term effects, the effect after 1 day of treatment (day 1), and for weekly effect (change from day 1 to day 5 of a given treatment week). Significant decreases were seen in the spontaneous cytotoxicity of peripheral blood NK cells and IL-2-inducible LAK cells, whereas increases in spontaneous peripheral blood LAK activity were seen with TNF treatment. Consistent increases in superoxide production of resting PMN and MNC were demonstrated, with late increases in superoxide production by opsonized, zymosan-treated PMN. No spontaneous IFN-gamma or IL-2 were noted in sera with treatment, but production of IL-2 by MNCs rose with TNF treatment. During 5 days of TNF treatment, the percentages of circulating CD8+ and CD56+ cells decreased, whereas that of CD4+ and CD19+ cells increased significantly and consistently, as determined by a multivariate analysis. Significant changes in several independently measured parameters were observed, including a dose-related diminished production of IFN-gamma by MNC stimulated by phytohemagglutinin and increased in vitro-generated LAK activity. Because there was no clinical response in this trial, no association of immunologic change with clinical response can be made. No biologically optimal dose of TNF was evident. The data suggest that TNF may act as a trigger cytokine, initiating a broad immune/inflammatory response.

Dose-Response Relationship, Immunologic↗
PubMed1996

Phase II trial of interferon-alpha in locally recurrent or metastatic squamous cell carcinoma of the head and neck: immunological and clinical correlates.

The objective of this study was to study the antitumor, host toxicity, and immunomodulatory effects of recombinant interferon-alpha 2b (IFN) in patients with recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN). Seventy-one patients with recurrent or metastatic SCCHN were entered into a phase II noncomparative randomized trial of IFN at two dosage schedules. Eligible patients with histologically proven SCCHN were randomized to receive low-dose IFN, 6 x 10(6) U/m2 daily x 3 every 4 weeks or high-dose IFN, 12 x 10(6) U/m2, 3 x/week. Pretreatment levels of natural killer (NK) activity, CD3, CD4, CD5, CD8, CD16, CD19, CD56, DR, and the CD4/CD8 ratio were evaluated for any relationship with survival. The toxicity encountered in patients receiving low-dose IFN was for the most part mild to moderate. With high-dose IFN, toxicity was greater with significantly more episodes of grade 3 and 4 toxicity encountered. Dosage reduction was required in the majority of patients receiving high-dose IFN. Of the four lethal complications, only one was thought to be possibly associated with therapy. Of the 32 evaluable patients receiving low-dose IFN, there were 1 complete response, 1 stable disease, 24 patients with progressive disease, and 6 unevaluable. Of the 29 evaluable patients taking high-dose IFN, there were 2 complete responses, 7 with stable disease, 16 with progressive disease, and 4 patients were unevaluable. Median survival in the two arms was similar (6.2 months). Because it was postulated that a more prolonged exposure to IFN might be needed for it to be effective, patients receiving > or = 6 weeks of therapy were evaluated. Median survival in that subset was 10 and 12 months for patients receiving low- and high-dose IFN, respectively. None of the immune parameters tested was a significant predictor of survival when evaluated in all cases entered into study regardless of therapy duration. No difference in baseline NK activity was noted between patients who received < 6 or > or = 6 weeks of IFN (p = 0.90). However, among the 35 patients who received > or = 6 weeks of therapy, a high baseline NK activity was a significant predictor of the duration of survival (p = 0.04). IFN was well tolerated in patients with recurrent or metastatic SCCHN. The higher incidence of toxicity encountered in the high-dose arm could be ameliorated by reducing the dose 50%. In patients receiving 6 or more weeks of therapy, elevated baseline NK activity was associated with increases in survival, suggesting that IFN may play an immunomodulatory role. Although the overall response rates were low, disease stabilization was noted, suggesting an antiproliferative, noncytotoxic role of IFN in this group of heavily pretreated patients.

Adult↗
PubMed1994

Potentiation by interleukin 1 alpha of cisplatin and carboplatin antitumor activity: schedule-dependent and pharmacokinetic effects in the RIF-1 tumor model.

We have previously demonstrated that the cytokine interleukin 1 alpha (IL-1 alpha) significantly potentiates the antitumor activity of a variety of chemotherapeutic agents, including cisplatin (cDDP). In studies described here, we examined the potential of combining IL-1 alpha and the platinum analogue carboplatin (CBDCA) and compared the schedule-dependent and pharmacokinetic effects for IL-1 alpha combinations with cDDP and CBDCA. RIF-1 tumor-bearing mice (C3H/HeJ) received i.p. injections of varying doses of CBDCA, alone or concurrently with IL-1 alpha (48 or 480 micrograms/kg). Clonogenic cell kill and tumor regrowth delay were significantly increased when CBDCA was combined with IL-1 alpha, at both doses, compared to either CBDCA or IL-1 alpha alone (P < 0.001 and P < 0.01, respectively). Although pretreatment with IL-1 receptor antagonist blocked the acute tumor hemorrhagic response induced by IL-1 alpha alone, IL-1 receptor antagonist only partially blocked IL-1 alpha enhancement of CBDCA or cDDP-mediated tumor cell kill. The IL-1 alpha enhancement of CBDCA-mediated tumor cell kill was highly schedule dependent, with maximum antitumor activity observed when IL-1 alpha was administered 4-12 h before CBDCA. In contrast, administration of IL-1 alpha from 24 h before or as late as 6 h after cDDP resulted in the same antitumor activity as simultaneous administration of cDDP and IL-1 alpha. Tumor and normal tissue platinum content were significantly increased by IL-1 alpha in animals treated with CBDCA (P < 0.01) but not in those treated with cDDP. The observed differences between cDDP and CBDCA may be explained by their known differential rates of clearance and protein binding affinities and are compatible with an induced alteration in CBDCA pharmacokinetics.

Animals↗
PubMed1994

Phase Ib trial of the effect of peritumoral and intranodal injections of interleukin-2 in patients with advanced squamous cell carcinoma of the head and neck: an Eastern Cooperative Oncology Group trial.

Thirty-six patients with unresectable squamous cell carcinoma of the head and neck were entered into a phase Ib trial evaluating the toxicity, maximally tolerated dose (MTD), and immunomodulating effects of locally administered interleukin-2 (IL-2). Patients received daily IL-2 injected perilesionally in divided doses in each of four quadrants and bilaterally into the superior jugular lymph nodes. The dose of IL-2 began at 200 U/day and was escalated to 4 x 10(6) U/day in groups of six patients. Overall, regionally administered IL-2 was well tolerated. The most frequently encountered toxicities were fever, hepatotoxicity, and hypotension. Dose-limiting toxicity was encountered at 4 x 10(6) U. Of the 36 patients treated, 2 partial responses were noted at 2,000 and 4 x 10(6) U. We conclude that regionally administered IL-2 is well tolerated in patients with head and neck cancer and that the MTD is 2 x 10(6) U/day, similar to what has been reported with systemically administered IL-2. Although the overall response rate was low, it may be improved with prolonged administration of IL-2 or by combining it with other biologic or cytotoxic agents.

Adult↗
PubMed1993

Cross-reactivity between murine melanoma antigen B700 and a human melanoma-associated antigen (M-66) recognized by autologous antibody: evidence suggesting shared epitopes.

We have previously reported the purification and partial characterization of a human melanoma-associated antigen (M-66) recognized by autologous antibody. This antigen was found to be an unusually acidic 66 kDa glycoprotein. In studies of murine melanoma, a 67-kDa albumin-like melanoma-associated antigen (MAA) isolated from B16 melanoma cells has also been reported by our laboratories. Because the murine MAA, B700, has a molecular weight that is nearly the same as M-66, we sought to determine what similarities and differences existed between these two antigens. Human sera S150, which is known to recognize M-66, was found to bind to murine melanoma cell line B16. The addition of purified M-66 inhibited binding of S150 to B16 cells. Binding by S150 was not noted against murine melanoma cell line S91, which is known not to express cell surface B700. Conversely, reactivity of S150 against Y-Mel 84:420, known to express M-66, could be inhibited by preincubation with B16 cells. Four monoclonal antibodies known to recognize B700 were evaluated for-binding against murine B16 and human melanoma cell line Y-Mel 84:420. Binding was noted against both B16 and Y-Mel 84:420 which could be inhibited by the addition of M-66. Binding of S150 was also noted against purified B700 as tested by ELISA. While a comparison of the amino acid composition of the two antigens revealed similarities, M-66 contained 2.8 times as much serine and 0.4 times as much proline as B700. B700 has been reported to be related to serum albumin, which is not the case for M-66.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Isolation and purification of a squamous cell carcinoma of the head and neck-associated antigen identified by autologous antibody.

We have previously shown that detection of autologous antibody activity to squamous cell carcinoma of the head and neck may be augmented by dissociation of immune complexes. Western blot analysis with autologous antibody has identified a 60 kDa squamous cell carcinoma of the head and neck-associated antigen in spent media and immune complex-dissociated serum ultrafiltrate not recognized by normal human sera. Antigen-containing fractions of spent media were eluted from anion exchange columns immediately after serum albumin indicating that the antigen has an acidic pI < 4. Preparative purification of the squamous cell carcinoma antigen was accomplished by anion exchange of concentrated spent media (protein concentration 300 mg/ml) followed by lectin affinity chromatography with a Triticum vulgaris column. A single 60 kDa band was detected by silver stain and Western blot in antigen-containing fractions eluted following lectin affinity chromatography and SDS-PAGE. Final concentration of the antigen was determined to be 1 microgram/ml of protein with relative activity increased 1600 x over unfractionated spent media. We conclude that a squamous cell carcinoma of the head and neck-associated antigen, detected by autologous antibody, is an acidic 60 kDa glycoprotein.

Antibodies↗
PubMed1993

Synergistic enhancement by interleukin-1 alpha of cisplatin-mediated antitumor activity in RIF-1 tumor-bearing C3H/HeJ mice.

Administration of interleukin-1 alpha (IL-1 alpha) plus certain cytotoxic drugs causes substantially greater clonogenic tumor-cell kill and tumor-regrowth delay than does treatment with either agent alone. IL-1 alpha itself has little effect on tumor growth despite its ability to induce acute hemorrhagic necrosis, restrict tumor blood flow, and cause microvascular injury in a variety of murine model systems. To investigate further IL-1 alpha's ability to enhance the antitumor activity of cytotoxic drugs, we initiated studies to examine the effect of IL-1 alpha on cisplatin (cDDP)-mediated cytotoxicity using the RIF-1 tumor system. The antitumor activity of IL-1 alpha and cDDP was quantitated through standard clonogenic tumor-cell survival assays, a tumor hemorrhagic necrosis assay and tumor-regrowth delay studies, with the interaction between IL-1 alpha and cDDP being analyzed through median dose-effect. In vitro, IL-1 alpha had no enhancing effect on the cDDP-mediated tumor-cell kill. For examination of the in vivo efficacy of this regimen, RIF-1 tumor-bearing C3H/HeJ mice (14 days postimplantation) were treated concurrently with single i.p. injections of IL-1 alpha and/or cDDP at various doses. The increased clonogenic tumor-cell kill obtained with IL-1 alpha/cDDP was dose-dependent, with significant enhancement by IL-1 alpha being observed (P < 0.001), even at the lowest doses tested (2 mg/kg and 6 micrograms/kg for cDDP and IL-1 alpha, respectively), but it did not correlate with an increase in tumor hemorrhage. Using median dose-effect analysis, this interaction was determined to be strongly synergistic. When treated animals were monitored for long-term antitumor effects, combinations with IL-1 alpha significantly increased the tumor-regrowth delay and decreased the fractional tumor volume (P < 0.001). These results demonstrate that IL-1 alpha synergistically enhances cDDP mediated in vivo antitumor activity and suggest that the combination of IL-1 alpha and cDDP may have potential therapeutic application in the design of effective treatment modalities for cancer.

Animals↗
PubMed1993

Phase I/II study of murine monoclonal antibody-ricin A chain (XOMAZYME-Mel) immunoconjugate plus cyclosporine A in patients with metastatic melanoma.

XOMAZYME-Mel (XMMME-001-RTA) is an immunoconjugate comprised of ricin A chain conjugated to a murine monoclonal antibody directed against high molecular weight melanoma antigens. Although not necessarily related to increased toxicity or decreased efficacy, the development of anti-immunoconjugate antibodies may limit repetitive dosing with an immunoconjugate. We evaluated the role of cyclosporine A in blocking the antibody response in patients with melanoma treated with XMMME-001-RTA. Patients received cyclosporine in divided daily doses to achieve serum levels by HPLC of 150-200 ng/ml on days 1-22. On day 3, XMMME-001-RTA was begun at dosages 0.2-0.6 mg/kg daily for 5 days. Treatment was repeated every 35 days. Three patients were treated in each dosage tier (0.2, 0.4, 0.6 mg/kg). Nine patients were entered and all nine were evaluable. Patients had histologically confirmed melanoma. Metastatic sites included skin, soft tissue, and lymph nodes (seven), lung (two), liver (one), and spleen (one). There were four men and five women aged 46-75 years. Toxicities included myalgia, arthralgia, hypoalbuminemia, fatigue, elevations in liver function tests, and increased peripheral edema. Four patients received two to five repeated dosages of XMMME-001-RTA. One wheal-and-flare reaction from an immunotoxin test dose of XMMME-001-RTA was noted after five cycles. After a test dose subsequent to one cycle, two patients experienced chest tightness without ECG changes and were removed from the study. All toxicities resolved without sequelae. One patient experienced partial lymph node remission for 9 months. A second patient had stable mediastinal disease for 20 months. XMMME-001-RTA is safe when given repeatedly with cyclosporine.

Aged↗
PubMed1993

Clinical correlates of circulating immune complexes and antibody reactivity in squamous cell carcinoma of the head and neck. The Department of Veterans Affairs Laryngeal Cancer Study Group.

PURPOSE: To evaluate the correlation between the presence and titer of host-derived antibody reactivity, circulating immune complexes, and clinical course and prognosis in patients with squamous cell carcinoma of the head and neck (SCCHN). MATERIALS AND METHODS: Serum samples, obtained from untreated patients with squamous cell carcinoma of the larynx entered onto a multiinstitutional trial, were evaluated for the presence of elevated circulating immune complexes (221 patients) and host-derived antibody directed against two SCCHN cell lines (107 patients). RESULTS: Patients had significantly elevated levels of circulating immune complexes as measured by C1q binding compared with normal controls. Patients with higher levels of circulating immune complexes were less likely to respond to chemotherapy. No correlations were noted between immune complex levels and stage of disease, nodal status, site of disease, recurrence, or survival. Evaluation of native antibody titers for their relationship to clinical correlates showed no statistically significant associations. In sera subjected to immune complex dissociation, patients with moderately or poorly differentiated tumors had significantly higher antibody titers when compared with patients with well-differentiated tumors. Because marked variation in the increase of antibody titers following immune complex dissociation was noted, the ratio of immune complex-dissociated to native antibody titer was examined. Patients with a high ratio had a lower proportion of complete and partial responses to chemotherapy. CONCLUSION: Our results support the conclusion that the formation of tumor-associated immune complexes in patients with SCCHN is associated with a decreased response to chemotherapy.

Antibodies, Neoplasm↗
PubMed1992

Homozygous deletions within human chromosome band 9p21 in melanoma.

Genetic studies have implicated the early involvement of a gene on chromosome arm 9p in the development of cutaneous melanoma. We have performed loss-of-heterozygosity studies to confirm these original findings and identify the most frequently rearranged or deleted region of 9p. Eight markers were analyzed, including (from 9pter to proximal 9q) D9S33, the beta-interferon (IFNB1) locus, the alpha-interferon (IFNA) gene cluster, D9S126, D9S3, D9S19, the glycoprotein 4 beta-galactosyltransferase (GGTB2) gene, and the argininosuccinate synthetase pseudogene 3 (ASSP3). Two or more of these loci were found to be hemizygously reduced in 12 of 14 (86%) informative metastatic melanoma tumor and cell line DNAs, and homozygous deletions of the marker D9S126 were observed in 2 of 20 (10%) melanoma cell lines. These findings have resulted in the identification of a small critical region of 2-3 megabases on 9p21 in which a putative melanoma tumor-suppressor gene appears likely to reside. Several 9p candidate genes, including IFNB1, the IFNA gene cluster, GGTB2, and the tyrosinase-related protein (TYRP) locus, have all been eliminated as potential targets because they are located outside of the homozygously deleted regions.

Base Sequence↗
PubMed1992

Serial studies of autologous antibody reactivity to squamous cell carcinoma of the head and neck.

In previous studies we evaluated the incidence and specificity of autologous antibody reactivity against squamous cell carcinoma of the head and neck (SCCHN). We were able to demonstrate that autologous antibody reactivity is present in native sera but was usually of too low a titer to allow further analysis. Dissociation of immune complexes by acidification and ultrafiltration of serum augmented autologous antibody reactivity in nine out of nine autologous systems tested. Native antibody and antibody derived from immune complexes produced by the host and reactive with autologous tumor cells may be directed against physiologically relevant antigens. Therefore, correlations of antibody titers with clinical course may provide insight into the nature of the host response to cancer. In the present analysis, serological studies of six patients with SCCHN were performed with serum samples obtained over many months. Results of serial serological assays were correlated to tumor progression and clinical course. Fluctuations in autologous antibody reactivity were noted over time. In four cases, rises in autologous antibody titers preceded the clinical diagnosis of recurrence by several months. Drops in autologous antibody reactivity were noted in two cases following surgery or radiation therapy. In two cases of long-term survivors, no correlation between antibody reactivity and clinical course was noted. Specificity analysis of the six autologous systems demonstrated reactivity against autologous and allogeneic SCCHN as well as melanoma cell lines. These sera did not react with glioma, neuroblastoma, renal cell, breast, bladder and colon carcinoma cell lines nor with fetal calf serum, pooled lymphocytes, red blood cells and platelets. Autologous serial serological studies may provide a means by which to evaluate the host/tumor relationship in patients with SCCHN.

Aged↗
PubMed1992

Modulation by interferon alpha and gamma of the expression of a melanoma-associated antigen detected by autologous antibody.

Interferons (IFN) are known to alter the expression of histocompatibility and tumour-associated antigens. We have reported the isolation and purification of a 66-kD melanoma-associated antigen (MAA) that is recognized by the host. Competitive binding with MAA reduced autologous antibody binding to five melanoma cell lines, suggesting that a similar antigen is detected by other patients with melanoma. Nine melanoma cell lines were incubated for 3 days with 0.01-100 units/ml of interferon alpha (IFN-alpha) or interferon gamma (IFN-gamma) and the maximum titre of autologous antibody reactivity was determined by protein A haemadsorption. Incubation with IFN-alpha or IFN-gamma resulted in a decrease in maximum titre of autologous antibody reactivity directed against all melanoma cell lines. A 3-day incubation of three melanoma cell lines with IFN-gamma augmented the expression of HLA-DR, as has been reported by others. Incubation with spent media from autologous melanoma cells exposed to IFN-alpha inhibited autologous antibody binding less than control media from melanoma cells to which no IFN was added, indicative of decreased production or internalization of MAA. Conversely, incubation with spent media obtained after exposure to IFN-gamma inhibited autologous antibody binding to a greater degree than control spent media, consistent with increased shedding of antigen. These results suggest that IFN-alpha and IFN-gamma down-regulate the expression of MAA detected by autologous antibody by different mechanisms of action.

Antigenic Modulation↗
PubMed1991

Purification and partial characterization of a shed 66 kDa melanoma-associated antigen identified by autologous antibody.

We have previously reported the isolation of a 66 kDa melanoma-associated antigen, identified by autologous antibody, in serum and unfractionated spent tissue culture media by Western blot analysis. The antigen, detected by autologous serum S150, was found to be broadly represented on melanoma, glioma, renal cell carcinoma, neuroblastoma and head and neck carcinoma cell lines. S150 did not react with bladder or colon carcinoma, fetal fibroblasts, pooled platelets, lymphocytes and red blood cells, autologous cultured lymphocytes or fetal calf serum. To further characterize the antigen, spent tissue culture media, obtained from autologous melanoma cell line, Y-Mel 84:420, was separated by an isoelectric focusing column. Unabsorbed control serum S150 was noted to have a maximum titer of 1:2040 against autologous melanoma cells as measured by protein A hemadsorption. Following isoelectric focusing the greatest decrease in autologous antibody titer (30-fold) occurred with fractions having a pI between 2 and 3. Further resolution of the antigen was accomplished with high-pressure ion-exchange chromatography. One of these fractions showed a significantly higher concentration of antigen and was distinctly resolved from bulk serum albumin. Subsequent Western blot analysis, with autologous antibody, of the isolated antigen-containing fraction, confirmed the presence of a single 66 kDa band. Exposure of the antigen, purified by high-pressure ion-exchange chromatography, to neuraminidase ablated recognition by autologous antibody and suggests that sialic acid is present on the protein and may be part of the antigenic epitope. Binding of antigen, obtained following DEAE anion exchange chromatography, was noted to lectins derived from Triticum vulgaris, Dolichos biflorus and Lycopersicon esculentum. Preparative purification of the antigen was accomplished by anion exchange followed by lectin affinity chromatography with a Dolichos biflorus column. Antigen obtained following lectin affinity chromatography subjected to SDS-PAGE and silver stain revealed a single band at 66 kDa. We conclude that a melanoma-associated antigen detected by autologous antibody in spent tissue culture media is an unusually acidic glycoprotein (pI 2-3).

Antigens, Neoplasm↗
PubMed1991

Immunobiologic aspects of head and neck cancer. Clinical and laboratory correlates.

The role of the immune system in the pathogenesis and treatment of cancer remains to be determined. Impairment of humoral and cellular immunity has been associated with various factors implicated in head and neck cancer--tobacco, alcohol, and malnutrition. Whether these immune dysfunctions are causative or a secondary effect is not known. Patients with head and neck cancer have well-documented defects in immune function. In general, depression in cellular immunity has been noted, which can be correlated with stage of disease and prognosis. Conversely, increased humoral immune responses are seen, especially salivary IgA and circulating immune complexes. It may be that IgA or immune complexes are capable of suppressing the cellular immune response. Clinical trials utilizing biologic response modifiers in head and neck cancer have begun. Preliminary studies with heavily pretreated patients have demonstrated antitumor activity, suggesting that immunotherapy may provide a treatment alternative. In conclusion, the weight of evidence suggests that the immune response to head and neck cancer does play a role in the pathogenesis of the disease. A better understanding of the host-tumor interaction will allow for improved utilization of biologic response modifiers in the treatment of head and neck cancer.

Antibody Formation↗