lewis-y-antigen and Carcinoma--Small-Cell

The advantage of tissue microarray (TMA) is its ability to efficiently analyze large numbers of tissue specimens in a methodologically uniform way. The reliability of TMAs, especially with regard to clinicopathological characterizations, when compared to conventional immunohistochemistry (IHC) was evaluated.. Seventy-two embedded tissue sections from lung cancer specimens were stained with monoclonal antibodies against the tumor-associated markers TA-MUC1 and Lewis Y. Three representative cores of every tumor were embedded in a paraffin array multiblock. The IHC was evaluated by the immunoreactive score (IRS).. The data for the TMA IHC and the conventional IHC were concordant (kappa > or = 80%) for both markers. Likewise, discordance (McNemar's test) was low, and sensitivity and specificity were above 80% for both markers. In the samples with high positive expression, the concordance increased (kappa > or = 90%), discordance disappeared (McNemar p = 1.0), and sensitivity and specificity increased above 90% for both markers. Using Cox regression models, all the clinicopathological dependencies were equivalent for both techniques and both markers.. Immunohistochemistry with tissue microarrays is valid and provides results equivalent to conventional immunohistochemistry with respect to expression patterns and clinicopathological characterizations.

Topics: Aged; Antibodies, Monoclonal; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Female; Humans; Immunohistochemistry; Lewis Blood Group Antigens; Lung Neoplasms; Male; Middle Aged; Mucin-1; Prognosis; Staining and Labeling; Tissue Array Analysis

Lewis Y (Le(y)) is a blood group antigen with robust expression on the surface of epithelial tumors, including small cell lung cancer (SCLC), making it a potential target for antibody-based immunotherapy. 3S193, an immunoglobulin G3 monoclonal antibody, has demonstrated superior specificity, affinity, and cytotoxicity over other anti-Le(y) antibodies. A phase I trial of humanized 3S193 (hu3S193) with dosing up to 40 mg/m2 demonstrated tumor targeting without serious toxicities or the development of human anti-human antibodies.. We tested the targeting and pharmacokinetics of hu3S193 in patients with SCLC. Eligibility required progressive SCLC treated with up to three previous chemotherapy regimens, measurable disease not previously irradiated, and tumor samples positive for 3S193 by immunohistochemistry. Patients received four weekly injections of hu3S193, five patients at 10 mg/m2 and five patients at 20 mg/m2. The first and fourth injections were radiolabeled with indium-111 for gamma camera imaging.. Of 40 patients screened, 25 of 34 (74%) assessable SCLC tumor samples were 3S193 positive by immunohistochemistry. Ten patients were treated with hu3S193; nine completed all four injections. All fluorodeoxyglucose (FDG)-avid lesions >2 cm were visualized on antibody single-photon emission computed tomography. Some lesions overlying vascular structures could not be visualized. No difference was noted in imaging or pharmacokinetics between the first and fourth injections. Toxicities included grade 2 urticaria (n = 1), grade 1 vomiting (n = 2), and grade 2 hypertension (n = 1) transiently after infusion at the higher dose.. Given the strong tumor targeting, particularly at the higher dose, the favorable toxicity profile, and the potential for immunomodulatory effects, hu3S193 warrants further investigation in SCLC.

Topics: Adult; Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Bone Neoplasms; Brain Neoplasms; Carcinoma, Small Cell; Female; Humans; Indium Radioisotopes; Lewis Blood Group Antigens; Liver Neoplasms; Lung Neoplasms; Male; Middle Aged; Pilot Projects; Radioimmunotherapy; Time Factors; Tissue Distribution; Treatment Outcome

The SGN-15 monoclonal antibody-doxorubicin immunoconjugate is toxic to Lewis(Y) antigen-expressing cells and is effective against intracerebral tumors in nude rats when delivery is enhanced with osmotic disruption of the blood-brain barrier (BBB). We tested whether doxorubicin released locally in antigen-expressing cells would affect adjacent non-antigen-expressing cells in heterogeneously expressing intracerebral tumors.. Nude rats with intracerebral xenografts of human small cell lung carcinoma cells with high (n = 10) or low (n = 23) Lewis(Y) antigen expression were treated with SGN-15 at a low (10 mg/kg) or high (140 mg/kg) antibody dose, administered intra-arterially with BBB disruption, and tumor volumes and antigen expression were evaluated after 6 days.. BBB disruption-enhanced delivery of SGN-15 (10 mg/kg) reduced the high-expressor tumor volume from 26.1 +/- 3.7 mm(3) (n = 7) in untreated control animals to 6.7 +/- 4.6 mm(3) (n = 3, P < 0.05). Untreated high-expressor tumors exhibited uniform prominent Lewis(Y) antigen staining (97.6 +/- 0.9% positive, n = 4), whereas treated tumors demonstrated areas of nil, moderate, and prominent staining (71.0 +/- 8.5% positive, n = 3, P < 0.05). In intracerebral tumors with low initial antigen expression, BBB disruption-enhanced delivery of a low dose of immunoconjugate was significantly effective, but treated tumors demonstrated low levels of antigen expression. An increase in the immunoconjugate dose did not significantly alter either efficacy or antigen expression.. Immunoconjugate delivered across the BBB was effective against antigen-positive tumor cells, but there was not an effective chemical bystander effect against antigen-negative tumor cells.

Topics: Animals; Antibodies, Monoclonal; Antigens, Heterophile; Brain Neoplasms; Carcinoma, Small Cell; Cell Line, Tumor; Disease Models, Animal; Doxorubicin; Female; Humans; Lewis Blood Group Antigens; Rats; Rats, Nude; Xenograft Model Antitumor Assays