EP0544898A1

EP0544898A1 - Early diagnosis of lung cancer using anti-carbohydrate antibody combinations

Info

Publication number: EP0544898A1
Application number: EP19920915038
Authority: EP
Inventors: Daizo Saito; Sen-Itiroh Hakomori; Satoshi c/o Showa Univ. School of Med. KIMURA
Original assignee: Biomembrane Institute
Current assignee: Biomembrane Institute
Priority date: 1991-06-26
Filing date: 1992-06-25
Publication date: 1993-06-09
Also published as: WO1993000588A1; JPH06503177A

Abstract

Des procédés sont décrits pour la détection du cancer du poumon utilisant des combinaisons d'anticorps dirigés contre des séquences d'hydrates de carbone dans des molécules de lipide ou de protéine résidant à la surface des cellules cancéreuses. La présente invention concerne également les procédés de contrôle de l'efficacité de la thérapie contre le cancer du poumon.Methods are described for the detection of lung cancer using combinations of antibodies to carbohydrate sequences in lipid or protein molecules residing on the surface of cancer cells. The present invention also relates to methods of monitoring the effectiveness of therapy against lung cancer.

Description

EARLY DIAGNOSIS OF LUNG CANCER USING ANTI-CARBOHYDRATE ANTIBODY COMBINATIONS

Technical Field

The present invention is generally directed toward the detection of lung cancer, and more specifically, toward such detection through the use of combinations of anti-carbohydrate antibodies.

Background of the Invention

Lung cancer is a leading cause of cancer deaths in the United States. For example, small cell carcinoma of the lung (SCLC), which accounts for 20%-25% of all lung cancer cases, is a highly malignant type of cancer, killing 95%-99% of the patients who contract it. While a combination of chemo- and radiation therapy has successfully increased the two-year survival of patients with limited stage disease from 1% to 30%, the two-year survival of patients with extensive disease has not been improved by current therapies. The disease metastasizes early and widely, generally rendering it inoperable.

Early and accurate diagnosis of SCLC is, therefore, essential in the proper management of patients with this disease and any approach which significantly improves the accuracy of diagnosis would be of benefit.

Due to the difficulties in the current approaches to the early diagnosis of lung cancer, there is a need in the art for improved methods. The present invention fills this need, and further provides other related advantages.

Summary of the Invention

Briefly stated, in one aspect, the present invention provides methods for the early diagnosis of lung cancer using combinations of anti-carbohydrate antibodies. In one embodiment, the method comprises contacting a sputum specimen with a panel of three or more antibodies, wherein there is at least one antibody specific for each of three antigens selected from the group consisting of Le^x, sialosyl Le^x, Le^y, Tn, sialosyl Tn and Le^a; and detecting the presence or absence of immunocomplex formation by each of the antibodies, whereby the presence of immunocomplex formation by any one antibody is indicative of the presence of lung cancer.

In another embodiment, the method comprises the steps of: (a) contacting one or more aliquots of a sputum specimen, taken from a warm-blooded animal, with an antibody specific for Le^x under conditions and for a time sufficient to allow immunocomplexes to form therefrom; (b) detecting the presence or absence of immunocomplexes formed between the antibody and the aliguot; (c) repeating steps (a) and (b) with an antibody specific for sialosyl Le^x; (d) repeating steps (a) and (b) with an antibody specific for Le^y; (e) repeating steps (a) and (b) with an antibody specific for Tn; (f) repeating steps (a) and (b) with an antibody specific for sialosyl Tn; and (g) repeating steps (a) and (b) with an antibody specific for Le^a; wherein the presence of immunocomplexes generated in any of steps (a) - (g) is indicative of the presence of lung cancer.

In another aspect of the present invention, methods are provided for monitoring the effectiveness of cancer therapy in a warm-blooded animal with lung cancer. In one embodiment, the method comprises contacting a first sputum specimen, taken from the warm-blooded animal prior to initiation of therapy, with a panel of three or more antibodies, wherein there is at least one antibody specific for each of three antigens selected from the group consisting of Le^x, sialosyl Le^x, Le^y, Tn, sialosyl Tn and Le^a; detecting the presence or absence of immunocomplex formation by each of the antibodies, wherein the presence of immunocomplex formation by any one antibody is indicative of the presence of lung cancer; and repeating the contacting and the detecting steps on a second sputum specimen taken from the animal subsequent to the initiation of therapy, thereby monitoring the effectiveness of the therapy in the animal.

In another embodiment, the method comprises the steps of: (a) contacting one or more aliquots of a first sputum specimen, taken from the warm-blooded animal prior to initiation of therapy, with an antibody specific for Le^x under conditions and for a time sufficient to allow immunocomplexes to form therefrom; (b) detecting the presence or absence of immunocomplexes formed between the antibody and the aliquot; (c) repeating steps (a) and (b) with an antibody specific for sialosyl Le^x; (d) repeating steps (a) and (b) with an antibody specific for Le^y; (e) repeating steps (a) and (b) with an antibody specific for Tn; (f) repeating steps (a) and (b) with an antibody specific for sialosyl Tn; (g) repeating steps (a) and (b) with an antibody specific for Le^a; wherein the presence of immunocomplexes generated in any of steps (a) - (g) is indicative of the presence of lung cancer; and (h) repeating steps (a) - (g) on a second sputum specimen taken from the warm-blooded animal subsequent to the initiation of therapy, thereby monitoring the effectiveness of the therapy in the animal.

These and other aspects of the present invention will become evident upon reference to the following detailed description and attached drawings. Brief Description of the Drawings

Figure 1 depicts a flowchart illustrating a procedure for preparing sputum specimens for staining, i.e., immunohistochemical or otherwise.

Figure 2 graphically illustrates the reactivity of various anti-carbohydrate antibodies with sputum specimens. The scores presented represent averages from immunohistochemical stainings of malignant or borderline cells in sputa. A total of 38 cases were collected; 11 Class C or B and 26 Class D or E.

Detailed Description of the Invention

The present invention is generally directed towards methods for early diagnosis of lung cancer or for monitoring the effectiveness of cancer therapy in a warm- blooded animal with lung cancer. More specifically, the disclosure of the present invention shows that combinations of anti-carbohydrate antibodies may be used to detect lung cancer.

A traditional method for detecting lung cancer has been Papanicolaou's stain. A problem with this method is that it does not detect cancer cells sufficiently early for therapeutic purposes. As disclosed within the present invention, lung cancer may be detected prior to clinical manifestations by the use of combinations of antibodies to certain antigens. Further it is easier to find malignant cells by the methods of the present invention than by Papanicolaou's staining.

The antigens found to be useful within the methods of the present invention include Le^x, dimeric Le^x, sialosyl Le^x, Le^y, sialosyl Tn, fucosyl GMl, Tn and Le^a. The structures of these antigens are depicted in Table 1.

Table 1

Antigen Structure Le^x Galβ1→4GlcNAcβ1→3Galβ1→4Glcβ1→1Cer

3

↑

Fucαl

dimeric Le^x

Galβ1→4GlcNAcβ1→3Ga1β1→4GlcNAcβ1→3Galβ1→4Glcβ1→1Cer

3 3

↑ ↑

Fucα1 Fucα1 sialosyl Le^x NeuAcα2→3Galβ1→4GlcNAcβ1→3Galβ1→4Glcβ1→1Cer

3

↑

Fucαl

Le^y Galβ1→4GlcNAcβ1→3Galy31→4Glcβ1→1Cer

2 3

↑ ↑

Fucα1 Fucα1

Sialosyl Tn NeuAcα2→6GalNAcα1→O-Ser/Thr fucosyl GMl Galβ1→3GalNAcβ1→4Gal β1→4Glcβ1→1Cer

2 3

↑ ↑

Fucα1 Fucα2

Tn GalNAcαl→o-Ser/Thr Le^a Galβ1→3GlcNAcβ1→3Galβ1→4Glcβ1→1Cer

4

↑

Fucα1 Gal represents galactose; GlcNAc represents N-acetylglucoseamine; Glc represents glucose; Fuc represents fucose; NeuAc represents N-acetylneuraminic acid; GalNAc represents N-acetylgalactoseamine; Ser represents serine; Thr represents threonine; and Cer represents ceramide. Ceramides are sphingolipid bases which are acylated on the amine with a fatty acid.

Antibodies employed in the present invention selectively bind (i.e., with an affinity of about 10⁷ liters/mol or higher) to the antigens listed above. The term "antibody," as used herein, includes both monoclonal and polyclonal antibodies and may be an intact molecule, a fragment thereof, or a functional equivalent thereof. The antibody may be genetically engineered. Examples of antibody fragments include F(ab')₂, Fab', Fab and Fv.

Briefly, polyclonal antibodies may be produced by immunization of an animal and subsequent collection of its sera. Immunization is accomplished, for example, by a systemic administration, such as by subcutaneous. intrasplenic or intramuscular injection, into a rabbit, rat or mouse. It is generally preferred to follow the initial immunization with one or more booster immunizations prior to sera collection. Such methodology is well known and described in a number of references.

While polyclonal antibodies may be employed in the present invention, monoclonal antibodies (MAbs) are preferred. MAbs suitable within the present invention include those of murine or human origin, or chimeric antibodies such as those which combine portions of both human and murine antibodies (i.e., antigen binding region of murine antibody plus constant regions of human antibody). Human and chimeric antibodies may be produced using methods known by those skilled in the art. Human antibodies and chimeric human-mouse antibodies are advantageous when administered clinically because they are less likely than murine antibodies to cause the production of anti-antibodies.

MAbs may be generally produced by the method of Kohler and Milstein (Nature 256:495-497, 1975; Eur. J. Immunol. 6:511-519, 1976). Briefly, the lymph nodes and/or spleens of an animal immunized with one of the antigens listed in Table 1 are fused with myeloma cells to form hybrid cell lines ("hybridomas" or "clones"). Each hybridoma secretes a single type of immunoglobulin and, like the myeloma cells, has the potential for indefinite cell division. It may be desirable to couple such molecules to a carrier to increase their immunogenicity. Suitable carriers include keyhole limpet hemocyanin, thyroglobulin, bovine serum albumin and derivatives thereof. An alternative to the production of MAbs via hybridomas is the creation of MAb expression libraries using bacteriophage and bacteria (e.g., Sastry et al., Proc. Natl. Acad. Sci USA 86:5728, 1989; Huse et al., Science 246:1275, 1989). Selection of antibodies exhibiting appropriate specificity may be performed in a variety of ways which will be evident to those skilled in the art.

Representative examples of MAbs suitable within the present invention include SH1, SH2, SNH3, AH6, TKH2, TKH6, and CA3F4. SH1 is an IgG₃ directed against Le^x (Singhal et al.. Cancer Res. 50: 1375-1380, 1990). SH2 is an IgG directed against SH2 (Singhal et al., ibid.). SNH3 is an IgM directed against sialosyl Le^x and has a specificity similar to that of CS-LEX (Fukushima et al., Cancer Res. 44:5279-5285, 1984). AH6 is an IgM directed against Le^y (Abe et al., Cancer Res. 46:2639-2644, 1986). TKH2 is an IgG₁ directed against sialosyl Tn (Kjeldsen et al., Cancer Res. 48:2214-2220, 1988). TKH5 is an IgG₃ directed against fucosyl GM1 (Kjeldsen et al., ibid.). TKH6 is an IgM directed against Tn (Kjeldsen et al., ibid.). CA3F4 is an IgG directed against Le^a (Young et al., J. Biol. Chem. 258:4890-4894. 1983). Numerous other MAbs to these antigens have been described (see Hakomori, Advances in Cancer Research 52:257-331, 1989 and the references cited within).

As disclosed within the present invention, antibodies against combinations of the above antigens may be used to detect lung cancer in a sample of lung cells, such as a sputum specimen. More than one antibody against a particular antigen may be employed, so long as there is at least one antibody for each of the other antigens selected. In a preferred embodiment, a panel of at least one antibody for each of the antigens Le^x, sialosyl Le^x, Le^y, sialosyl Tn, Tn and Le^a, is used. Particularly preferred antibodies for these antigens are, respectively, the MAbs SH1, SNH3, AH6, TKH2 , TKH6 and CA3F4. In other preferred embodiments, panels of at least one antibody for each of two or three antigens selected from Le^x, sialosyl Le^x, Le^y, sialosyl Tn, Tn and Le^a, may be used. For example, one or more antibodies for each of the antigens Le^x, Le^y and Le^a may form a panel. Given the teachings provided herein, it will be evident to those of ordinary skill in the art that other combinations of antibodies may be utilized.

Typically, antibodies for a combination of antigens are reacted individually with separate aliquots from a sputum specimen. However, where there is no interference between the antibodies in the binding to their respective antigens, a single aliquot may be analyzed either sequentially or simultaneously. The order in which testing of multiple aliquots (or testing of a single aliquot sequentially) by different antibodies is performed may be varied.

Detection of the presence of immunocomplexes formed between an antigen described above and an antibody specific for the antigen may be accomplished by a variety of known techniques, such as radioimmunoassays (RIA) and enzyme-linked immunosorbent assays (ELISA). Suitable immunoassays include the double monoclonal antibody sandwich immunoassay technique of David et al. (U.S. Patent 4,376,110); monoclonal-polyclonal antibody sandwich assays (Wide et al., in Kirkham and Hunter, eds., Radioimmunoassay Methods, E. and S. Livingstone, Edinburgh, 1970); the "western blot" method of Gordon et al. (U.S. Patent 4,452,901); immunoprecipitation of labeled ligand (Brown et al., J. Biol. Chem. 255:4980-4983, 1980); enzyme-linked immunosorbent assays as described by, for example, Raines and Ross (J. Biol. Chem. 257:5154-5160. 1982); immunocytochemical techniques, including the use of fluorochromes (Brooks et al., Clin. Exp. Immunol. 39: 477, 1980); and neutralization of activity (Bowen-Pope et al., Proc. Natl. Acad. Sci. USA 81:2396-2400, 1984). In addition to the immunoassays described above, a number of other immunoassays are available, including those described in U.S. Patent Nos.: 3,817,827; 3,850,752; 3,901,654; 3,935,074; 3,984,533; 3,996,345; 4,034,074; and 4,098,876.

For detection purposes, the antibodies may either be labeled or unlabeled. When unlabeled, the antibodies find use in agglutination assays. In addition, unlabeled antibodies can be used in combination with labeled molecules that are reactive with immunocomplexes, or in combination with labeled antibodies (second antibodies) that are reactive with the antibody directed against the compound, such as antibodies specific for immunoglobulin. Alternatively, the antibodies can be directly labeled. Where they are labeled, the reporter group can include radioisotopes, fluorophores, enzymes, luminescers, or dye particles. These and other labels are well known in the art and are described, for example, in the following U.S. patents: 3,766,162; 3,791,932; 3,817,837; 3,996,345; and 4,233,402.

In one preferred embodiment for detecting immunocomplexes, a reporter group is bound to the antibody. The step of detecting immunocomplexes involves removing substantially any unbound antibody and then detecting the presence of the reporter group. Unbound antibody is antibody which has not bound to the antigen.

In another preferred embodiment, a reporter group is bound to a second antibody capable of binding to the antibodies specific for the antigen. The step of detecting immunocomplexes involves (a) removing substantially any unbound antibody (i.e., antibody not bound to the antigen), (b) adding the second antibody, (c) removing substantially any unbound second antibody and then (d) detecting the presence of the reporter group. Where the antibody specific for the antigen is derived from a mouse, the second antibody is an anti-murine antibody.

In a third preferred embodiment for detecting immunocomplexes, a reporter group is bound to a molecule capable of binding to the immunocomplexes. The step of detecting involves (a) adding the molecule, (b) removing substantially any unbound molecule, and then (c) detecting the presence of the reporter group. An example of a molecule capable of binding to the immunocomplexes is protein A.

An alternative to the use of labeled antibodies, labeled second antibodies or labeled molecules reactive with immunocomplexes generally, is an immunoassay employing a labeled antigen. In such an assay, an antigen present in a sample will compete with labeled antigen for the antibodies.

It will be evident to those skilled in the art that a variety of methods for detecting immunocomplexes may be employed within the present invention. Reporter groups suitable for use in any of the methods include radioisotopes, fluorosphores, enzymes, luminescers, and dye particles.

In a related aspect of the present invention, detection of immunocomplexes, formed between a sputum specimen and an antibody specific for one of the antigens identified above, may be used to monitor the effectiveness of lung cancer therapy. Sputum specimens taken from a warm-blooded animal, such as a human, prior to and subsequent to initiation of therapy may be analyzed by the methods of the present invention described above. The absence of specific immunocomplexes in the subsequent sample (post-therapy initiation) reflects successful therapy.

The following examples are offered by way of illustration and not by way of limitation.

EXAMPLES

EXAMPLE 1

IMMUNOSTAINING OF SPUTUM SPECIMENS

A. Sputum Collection

Sputum was collected from subjects every morning for three days and stored in "Sacomano's solution" (2% polyethylene glycol in 50% ethanol) at room temperature. "High-risk" subjects were heavy smokers, i.e., at least one pack of cigarettes per day for 20 years. Staining of sputum specimens is preferably done within a few days after collection. However, specimens may be stored for six months at 4°C.

B. Staining of Sputum

Mucus was removed from sputum using a blender (e.g.. Waring^® blender model 31 BL91; 11,000 rpm for 10 seconds). Cells were collected in sediment by centrifugation at 2,000 rpm for 5 minutes. The cells were smeared on glass slides for immunohistological staining, and fixed with 95% ethanol for 10 minutes at room temperature. Papanicolaou's staining was also performed for grading malignancies. Fixed cells on the slides were washed twice with phosphate buffered saline (PBS) for 10 minutes at room temperature.

To enhance the specificity of the immunohistochemical staining, nonspecific binding sites on the cells were blocked with diluted (10%) normal mouse serum (component of Vectastain^® ABC Kit, Burlingame, Cal.) for 30 minutes at room temperature. Reaction with an anti-carbohydrate antibody (~0.1-10 μg/ml) was performed at 4°C overnight in a moisture chamber. Following the overnight incubation, the slides were twice washed with PBS for 10 minutes at room temperature. Any intrinsic peroxidases (i.e., peroxidases of the cells) were blocked by treatment with 0.3% H₂O₂/methanol for 30 minutes at room temperature. The slides were again twice washed with PBS for 10 minutes.

The slides were reacted with biotinylated secondary antibody (Vectastain^® ABC Kit) for 20 minutes at room temperature in a moisture chamber. The slides were washed three times with PBS for 5 minutes at room temperature. A preformed avidin-biotinylated horseradish peroxidase complex (Vectastain^® ABC Kit) was added for 30 minutes at room temperature in a moisture chamber. The slides were again washed three times with PBS for 5 minutes to remove unreacted complex.

The slides were dipped in a solution containing diamino benzidine (DAB, a substrate for horseradish peroxidase) and H₂O₂ (20 mg DAB, 30 μl H₂O₂, 65 mg NaN₃, 0.05M Tris chloride buffer, pH 7.6, final volume of 100 ml) for 5 minutes at room temperature. The slides were washed with distilled water for 5 minutes and counterstained with Meyer's Hematoxylin (Muto Chemicals, Tokyo, Japan) without dilution for 20 seconds at room temperature. The slides were washed with running water for 10 minutes and then sealed and examined under a microscope (~40x - 200x magnification). C. Staining Results

The results of histological evaluation of the specimens is shown in Table 2 below.

Table 2

Histology of Specimens specimen differentiation total well moderate poor cases squamous cell carcinoma 9 12 9 30 adenocarcinoma 13 8 9 30 small cell carcinoma* 27 oat cell type 6, intermediate cell type 18, mixed type 3 cases.

The results of cytological evaluation of the specimens is shown in Table 3 below. Class "B" represents normal or benign, "C" represents borderline malignancy, and "D" or "E" represents malignancy.

The results of the binding of anti-carbohydrate

MAbs is shown in Figure 2 (cells in sputum) and Table 4 (stained lung cancer tissue sections). MAbs SH1, SNH3,

AH6, TKH2, TKH6 and CA3F4 exhibited the strongest binding to lung cancer specimens.

The scores of paraffin-embedded lung cancer tissue sections which were stained positively with a MAb of Figure 2 are shown in Table 4 below. The scale ranges from 0 to a maximum of 3.00.

The incidence of positively-stained cells by MAb and class is shown in Table 5 below. Class "C" represents borderline malignancy and "D" or "E" represent clinically diagnosed malignancy.

The reactivity of specimens from patients with clinically manifested cases of lung cancer is shown in Table 6 below. Specimens from every patient showed positive staining with at least one anti-carbohydrate MAb.

The combination of anti-carbohydrate MAbs AH6, TKH2, SNH3, SH1, TKH6 and CA3F4 detects lung cancer up to about 18 months prior to clinical manifestation. As shown in Table 7 below, the positive ratio of malignant cells is significantly higher (p < 0.05). Table 7

No Positive Positive staining with Staining at least one antibody

Cancer 3 35

Atypical metaplasia 16 26 *Borderline malignancy stayed tumor-free for at least 6 months.

Fifty-eight cases of borderline malignancies were followed up for 18 months (Table 8). If staining is negative with all six MAbs listed in Table 6, the subject stays cancer-free for 18 months.

Table 8

No Positive Positive staining with Staining at least one antibody

Group I:

Suffered Cancer 0 10

Group II:

Stayed cancer-free 18 30

EXAMPLE 2

PRODUCTION OF MAbs AGAINST TUMOR-ASSOCIATED CARBOHYDRATE

ANTIGENS

MAbs may be produced against tumor-associated carbohydrate antigens by immunization of mice with purified glycoplipid antigen coated on Salmonella minnesota (Young et al., J. Exp. Med. 150:1008-19, 1979). The procedure for the preparation of MAb SH-1 is representative. Lewis^3** antigen (III³ Fuc nLc⁴) is purified from a human liver tumor metastasized from colonic cancer. The tumor is homogenized three times in isopropanol:hexane:H₂O and filtered. The organic extract is evaporated to dryness and partitioned three times by the method of Folch (J. Biol. Chem. 191:819, 1951). The combined upper phase is evaporated and dialyzed against distilled water in a spectrapore 3 (3500 mol. wt. cut-off) dialysis tubing. The dialysate is evaporated using excess ethanol and subjected to ion-exchange chromatography on DEAE-Sephadex A-25 column (4 x 50 cm). The sample is applied in chloroform:methanol:water (30:60:8). The nonbinding pass-through fraction is collected which contains Lewis^x antigen. The sample is evaporated and subjected to high-pressure liquid chromatography (HPLC) on an iotrobead system consisting of isopropanol:hexane:water (55:40:5 to 55:25:20).

The fractions are pooled on the basis of staining with orcinol-sulfuric acid. The glycolipids migrating between standard H₁ and H₂ glycolipids are pooled and acetylated using pyridine-acetic anhydride. The acetylated glycolipids are applied to a preparative TLC plate and developed in dichloroethanol:acetone:water (40:60:0.03). Each isolated band is analyzed by NMR and permethylation analysis, and Le^x band is collected.

Balb/c mice (female, 8-week-olds) are immunized with the purified Lewis^x antigen (III³ Fuc nLc4). The antigen (40 μg/100 μl ethanol) is injected into 800 μl phosphate-buffered saline (PBS) at 37ºC. The solution is further mixed with 250 μg of acid-treated S. minnesota (1 mg/ml PBS). The mixture is incubated at 37ºC. for 30 min and lyophilized. The lyophilized powder is resuspended in 1 ml PBS. Mice are immunized every 10 to 14 days apart by tail vein injection of 250 μl of antigen suspension of PBS.

Three days after the last injection, animals are killed by cervical dislocation and spleens are aseptically excised. Lymphocytes are fused with mouse myeloma SP² cells (5:1) using polyethylene glycol. Clones are screened after 11 days of fusion. The clones at this stage are small. Clones were screened using a Pandex machine, in which antigen is coated on submicron polystyrene particles. Antigen-coated beads are mixed with the antibody supernatants, followed by the addition of FITC-goat anti-mouse IgG and IgM. This assay ("Pandex assay") is two- to fourfold more sensitive than traditional radioimmunoassay or ELISA assay and requires only 10 ng of antigen/well as opposed to 50 to 100 ng/well in other assays. This screening procedure further facilitates the selection of a high-affinity antibody to Lewis^x. The clones that test positive are cloned by single-cell dilution and are also tested by TLC immunostaining. Clones producing MAb SH-1, showing high reactivity in the Pandex assay and in TLC immunostaining, are selected and frozen.

All publications and patents mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent was specifically and individually indicated to be incorporated by reference.

From the foregoing, it will be evident that, although specific embodiments of the invention have been described herein for purposes of illustration, various modification may be made without deviating from the spirit and scope of the invention.

Claims

1. A method for detecting lung cancer, comprising: contacting a sputum specimen with a panel of three or more antibodies, wherein there is at least one antibody specific for each of three antigens selected from the group consisting of Le^x, sialosyl Le^x, Le^y, Tn, sialosyl Tn and Le^a; and

detecting the presence or absence of immunocomplex formation by each of said antibodies, whereby the presence of immunocomplex formation by any one antibody is indicative of the presence of lung cancer.

2. A method for detecting lung cancer, comprising the steps of:

(a) contacting one or more aliquots of a sputum specimen, taken from a warm-blooded animal, with an antibody specific for Le^x under conditions and for a time sufficient to allow immunocomplexes to form therefrom;

(b) detecting the presence or absence of immunocomplexes formed between said antibody and said aliquot;

(c) repeating steps (a) and (b) with an antibody specific for sialosyl Le^x;

(d) repeating steps (a) and (b) with an antibody specific for Le^y;

(e) repeating steps (a) and (b) with an antibody specific for Tn;

(f) repeating steps (a) and (b) with an antibody specific for sialosyl Tn; and

(g) repeating steps (a) and (b) with an antibody specific for Le^a;

wherein the presence of immunocomplexes generated in any of steps (a) - (g) is indicative of the presence of lung cancer.

3. A method for monitoring the effectiveness of cancer therapy in a warm-blooded animal with lung cancer, comprising:

contacting a first sputum specimen, taken from the warm-blooded animal prior to initiation of therapy, with a panel of three or more antibodies, wherein there is at least one antibody specific for each of three antigens selected from the group consisting of Le^x, sialosyl Le^x, Le^y, Tn, sialosyl Tn and Le^a;

detecting the presence or absence of immunocomplex formation by each of said antibodies, wherein the presence of immunocomplex formation by any one antibody is indicative of the presence of lung cancer; and

repeating said contacting and said detecting steps on a second sputum specimen taken from the animal subsequent to the initiation of therapy, thereby monitoring the effectiveness of the therapy in the animal.

4. A method for monitoring the effectiveness of cancer therapy in a warm-blooded animal with lung cancer, comprising the steps of:

(a) contacting one or more aliquots of a first sputum specimen, taken from the warm-blooded animal prior to initiation of therapy, with an antibody specific for Le^x under conditions and for a time sufficient to allow immunocomplexes to form therefrom;

(c) repeating steps (a) and (b) with an antibody specific for sialosyl Le^x;

(d) repeating steps (a) and (b) with an antibody specific for Le^y;

(e) repeating steps (a) and (b) with an antibody specific for Tn;

(f) repeating steps (a) and (b) with an antibody specific for sialosyl Tn; (g) repeating steps (a) and (b) with an antibody specific for Le^a;

wherein the presence of immunocomplexes generated in any of steps (a) - (g) is indicative of the presence of lung cancer; and

(h) repeating steps (a) - (g) on a second sputum specimen taken from the warm-blooded animal subsequent to the initiation of therapy, thereby monitoring the effectiveness of the therapy in the animal.