International multicenter tool to predict the risk of four or more tumor-positive axillary lymph nodes in breast cancer patients with sentinel node macrometastases.

Recently, many centers have omitted routine axillary lymph node dissection (ALND) after metastatic sentinel node biopsy in breast cancer due to a growing body of literature. However, existing guidelines of adjuvant treatment planning are strongly based on axillary nodal stage. In this study, we aim to develop a novel international multicenter predictive tool to estimate a patient-specific risk of having four or more tumor-positive axillary lymph nodes (ALN) in patients with macrometastatic sentinel node(s) (SN). A series of 675 patients with macrometastatic SN and completion ALND from five European centers were analyzed by logistic regression analysis. A multivariate predictive model was created and validated internally by 367 additional patients and then externally by 760 additional patients from eight different centers. All statistical tests were two-sided. Prevalence of four or more tumor-positive ALN in each center's series (P = 0.010), number of metastatic SNs (P < 0.0001), number of negative SNs (P = 0.003), histological size of the primary tumor (P = 0.020), and extra-capsular extension of SN metastasis (P < 0.0001) were included in the predictive model. The model's area under the receiver operating characteristics curve was 0.766 in the internal validation and 0.774 in external validation. Our novel international multicenter-based predictive tool reliably estimates the risk of four or more axillary metastases after identifying macrometastatic SN(s) in breast cancer. Our tool performs well in internal and external validation, but needs to be further validated in each center before application to clinical use.

Radiolabeled monoclonal antibody 15 and its fragments for localization and imaging of xenografts of human lung cancer.

Monoclonal antibody (MAb) 15 and its F(ab')2 and Fab fragments were radioiodinated, and their biodistribution and imaging were compared in BALB/c nude mice bearing a xenograft of a human lung cancer (TKB-2). Association constants for 125I-labeled MAb 15 IgG, F(ab')2, and Fab were 1.9 X 10(9), 1.8 X 10(9), and 3.7 X 10(8) M-1, respectively. Immunoreactive fractions ranged from 0.59 to 0.50. Cultured TKB-2 cells expressed 1.1 X 10(4) binding sites/cell for MAb 15 IgG in vitro. The binding of a control antibody and the binding of its fragments to TKB-2 cells were less than 3% of the input doses. The mice with the TKB-2 tumors were given simultaneous injections of 10 microCi of 131I-labeled MAb 15 or its fragments and 10 microCi of 125I-labeled control IgG or its fragments. With MAb 15 IgG, the percentage of the injected dose bound per gram of tissue (ID/g) of the tumor was 3.68% at day 7, when the localization index (LI) was 4.38. At day 2 after MAb 15 F(ab')2 injection, 1.12% of the ID/g was localized in the tumor and the LI was 3.04. After MAb 15 Fab injection, the percentage of the ID/g of the tumor was 0.31% and the LI was 2.58 at day 1. MAb 15 IgG, F(ab')2, and Fab cleared from the blood early, with a half-life of 33, 16, and 9 hours, respectively. The distributions of MAb 15 and its fragments in the normal organs did not differ from those of the control. Radioimaging with 100 microCi of 131I-labeled MAb 15 and its fragments showed that 42%, 44%, and 32% of the total-body count were localized in the tumor with IgG at day 7, F(ab')2 at day 2, or Fab at day 1, respectively. Because the radioactivity remaining in the tumor with Fab was low, the image was insufficient. Throughout the period, less than 10% of the control IgG and its fragments remained in the tumor. Microautoradiography confirmed the binding of MAb 15 and its fragments to the tumor cells. In this study the F(ab')2 was the best compromise between the slowly cleared IgG and the poorly localized Fab in tumor imaging.

Two murine monoclonal antibodies against human lung cancer-associated antigens.

Two murine monoclonal antibodies, MAb 8 (immunoglobulin G3 kappa) and MAb 15 (immunoglobulin G1 kappa), were produced after immunization with TKB-2, a variant cell line of human small cell carcinoma of the lung. In enzyme-linked immunosorbent assay, these antibodies reacted with four major types of lung cancer cell lines and various extrapulmonary tumor cell lines. Immunohistological study, however, showed highly specific binding to lung cancers; MAb 8 bound to 68% of 65 lung cancers, and MAb 15 bound to 72% of them. Interestingly, both antibodies were more reactive with non-small cell than small cell lung cancers and bound most frequently to large cell carcinoma. Most extrapulmonary tumor tissues were negative in staining with a few exceptions; endodermal sinus tumor (two of two) was positive to both antibodies, breast carcinoma (one of five) to MAb 8, gastric carcinoma (one of three), and malignant melanoma (one of one) to MAb 15. Cross-reactions with normal tissues were limited; MAb 8 reacted with adult and fetal lung, and MAb 15 with esophagus and renal tubules. MAb 8 recognized a Mr 48,000 glycoprotein antigen (carbohydrates as its epitope), and MAb 15 recognized two proteins (Mr 85,000 and 45,000) (peptides as their epitopes). These two antibodies, detecting novel antigens extensively associated with and highly specific to lung cancers, are potentially useful for the study of lung cancer.

Radiolocalization of xenografted human lung cancer with monoclonal antibody 8 in nude mice.

A monoclonal antibody (MAb) 8 [immunoglobulin G3 (IgG3)], directed against a Mr 48,000 human lung cancer-associated antigen, was radiolabeled with either 125I or 131I, and its biodistribution was studied in nude mice bearing human lung cancer (TKB-2) over a 7-day period. 125I-labeled MAb 8 increased its binding to the tumor during the period, while the binding of 125I-labeled control IgG3 declined after initial uptake. At Day 7, percentages of injected dose of 125I-labeled MAb 8 bound to the tumor rose to 7.4%, which was a 4.4-fold increase from Day 1 and 16-fold binding of 125I-labeled control IgG3 at the same day. Tumor:blood ratios became 2.7:1 at Day 7, and tumor:liver, tumor:spleen, and tumor:kidney ratios were more than 9:1. Normal organs showed no significant uptake of 125I-labeled MAb 8, compared with those of 125I-labeled control IgG3. A clear image of the xenografted tumor was obtained at Day 5, and it further improved at Day 7, when 60% of whole body radioactivity was localized to the tumor. Autoradiography of the mouse with tumor confirmed the excellent localization of 125I-labeled MAb 8 to the tumor, although the radioactivity of the tumor was not uniformly distributed. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that most of the radioactivity was present at the tumor in the form of degraded immunoglobulin. MAb 8 has a potential usefulness in the diagnosis and treatment of lung cancer.

Lung cancer-associated monoclonal antibody 15 that recognizes cell growth-related membrane antigens gp85/45 and its growth-inhibitory effect on human lung cancer cells in vitro.

In order to find lung cancer-specific markers, monoclonal antibody 15 (MAb15) was produced against a variant-type cell of small cell lung carcinoma. Its gp85/45 antigens were demonstrated in 70% of lung cancers, and particularly in the proliferating zone of cancer cell nests, but they are scarcely detected in noncancerous tissues. Immunoelectron microscopy revealed that gp85/45 antigens were expressed alternatively on the cell membrane of living cancer cells according to their biological states. MAb15 added to the culture medium inhibited the proliferation of lung cancer cells, depending on its concentration, but cell death rate did not increase. The growth inhibition by MAb15 was reevaluated by a colonogenic assay. On DNA histogram, MAb15 decreased the number of DNA-synthesizing cells in the S phase with an elevation of the G1 peak, indicating a G1-S boundary block in the cell cycle. gp85/45 detected by this lung cancer-associated monoclonal antibody could be a functional membrane unit, such as a growth factor receptor, which is related to the cell proliferation of lung cancer. The growth inhibition by MAb15 may be caused by the blocking of a growth factor receptor which is specific to lung cancer.

Testis- and developmental stage-specific expression of hnRNP A2/B1 splicing isoforms, B0a/b.

Heterogeneous nuclear ribonucleoproteins (hnRNPs) A2 and B1 are abundant nuclear proteins that bind to nascent RNAs synthesized by RNA polymerase II. Previously we had found that the splicing isoforms hnRNP B0a/b, from which the ninth exon of the A2/B1 gene is excluded, are abundantly expressed in testis. We postulated that B0a/b are testis-specific isoforms, and investigated the expression of A2/B1 and B0a/b in rat tissues and in postnatal development of rat testes using RNase protection assay, immunoblotting, and immunohistochemistry. We found that hnRNP B0a/b mRNAs are expressed in several tissues but that the testis alone expresses B0a/b proteins. A sequential study using neonatal rat testes demonstrated that B0a/b mRNAs are produced after 17 days of age, but not translated until 4 weeks of age when round spermatids appear in addition to spermatogonia and spermatocytes. Immunohistochemically, hnRNP A2/B1 isoforms are expressed during spermatogenesis from spermatogonia through round spermatids, whereas the expression of A1 is restricted to spermatogonia. This expression pattern in the rat testis is maintained from birth through adulthood. These results suggest that the expression of the hnRNP A2/B1 gene is partly regulated by a testis-specific post-transcriptional mechanism, and that the products of the A2/B1 gene, especially hnRNP B0a/b, are involved in spermatogenesis.

MUC 1 core protein as a marker of gallbladder malignancy.

AIM: The significance of MUC 1 expression in the gallbladder tissues in relation to cancer and non-cancer disease is not well understood. The aim of this study was to clarify the significance of MUC 1 expression. MATERIALS AND METHODS: A monoclonal antibody (CA 15--3; DF 3) was applied to stain MUC 1 core protein in surgical specimens. RESULTS: MUC 1 expression is significantly higher (p<0.0001) in gallbladder cancer (69/88) compare to non-cancerous tissue, while, very trace in normal and inflammatory tissues. The expression rate was significantly lower (p<0.0001) when the cancer did not penetrate the mucosal layer than when cancers did penetrate this layer. The MUC 1 expression rate was (4/14) in T1 tumours, (11/14) in T4, (40/45) in T3, and (14/15) in T2, respectively. Every cell of normal and inflammatory mucosa, and T1 cancers had the polarized pattern. The depolarized pattern was dominant in cancer cells from the advanced tumours of T2, T3 and T4. That is, (45/74) of cancer cells from the mucosal layer and (58/74) of penetrating cancer cells in submucosal layer had the depolarized pattern. There was no significant correlation of MUC 1 expression rate and staining pattern with cancer differentiation and microscopic venous invasion. On the other hand, lymphatic vessel invasion was significantly correlated with the staining pattern but not with expression rate. CONCLUSION: MUC 1 core protein expression rate and pattern are suggesting that MUC 1 core protein would be a marker of malignant transformation of gallbladder epithelium and its depolarized expression would also be a marker of invasion of gallbladder cancer.

Serum sialyl lewis X-i antigen levels in non-small cell lung cancer: correlation with distant metastasis and survival.

To evaluate the correlation between serum levels of sialyl Lewis X-i antigen and distant metastasis and survival in patients with non-small cell lung cancer (NSCLC), we measured the serum levels of the tumor marker in 371 patients with untreated NSCLC. The sialyl Lewis X-i antigen level was measured using a RIA kit. In patients with adenocarcinoma or other NSCLC subtypes, there was a correlation between serum sialyl Lewis X-i antigen and stage of the disease (P = 0.0001 and P = 0.0015, respectively). Levels of the marker varied significantly depending on the number of metastatic organs in adenocarcinoma (P = 0.0089) and in other NSCLC subtypes (P = 0.002). Univariate analysis showed that survival of NSCLC patients with high (more than 100 units/ml) sialyl Lewis X-i antigen levels was significantly poorer than that of patients with low antigen levels (P = 0.0001). Multivariate analysis using Cox's proportional hazard model showed that high sialyl Lewis X-i antigen levels correlated significantly with poor survival (P = 0.004). Our data suggest that a high serum level of sialyl Lewis X-i antigen seems to be an indicator of the presence of metastasis and might indicate the need for a careful investigation of all putative metastatic sites. The serum levels of sialyl Lewis X-i antigen may reflect the extension of metastasis and would be helpful in considering treatment options.

Molecular characterization of a mouse heterogeneous nuclear ribonucleoprotein D-like protein JKTBP and its tissue-specific expression.

The human DNA- and RNA-binding protein JKTBP is a new member of heterogeneous nuclear ribonucleoproteins (hnRNPs) that are involved in mRNA biogenesis. We cloned and characterized a mouse homolog and studied its expression in mouse tissues. The cDNA encoded a 301-residue polypeptide. There is only a single amino acid difference between the mouse and human sequences. Northern blotting indicated ubiquitous but varied expressions of approximately 1.4 and 2.8kb mRNAs in various tissues. Immunoblotting indicated that the amounts of protein of about 38kDa were higher in the brain and testis than in other tissues. An additional protein of about 53kDa was found in the brain and testis. Germ cell-deficient W/W(v) mutant mice and aged mice had the reduced amounts of JKTBP in the testes. Immunohistochemical staining indicated cell type-specific expression of JKTBP in tissues: neurons and spermatocytes displayed strong signal intensities. The signals were confined to the nucleus. The amount of 38kDa JKTBP was estimated to be approximately 1.3x10(7) molecules per HL-60 cell. These results indicate that JKTBP is an abundant, highly conserved nuclear protein.

Characterization of hnRNP A2 and B1 using monoclonal antibodies: intracellular distribution and metabolism through cell cycle.

Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 are nuclear RNA binding proteins involved in pre-RNA processing. The alternative splicing of the second mini exon of A2/B1 gene produces A2 and less abundant B1. It has been reported that patients with autoimmune diseases frequently have blood autoantibody valence for A2/B1, and recently that the overexpression, especially of B1, is useful for detecting cancers in early stage. Three anti-A2/B1 monoclonal antibodies were developed using recombinant A2 protein and synthesized peptides around the second splicing site. Three antibodies could separately recognize A2 and B1, and their specificity made them useful in the study of the biochemical and functional properties of A2 and B1. These antibodies have demonstrated differences between A2 and B1 in the intracellular distribution and in the metabolism through cell cycle. They are valuable reagents to clarify the clinical significance of A2/B1 in autoimmune diseases and cancers.

Expression of hnRNP A2/B1 proteins in human cancer cell lines.

The overexpression of heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 is recently reported informative as a marker of lung cancer for early detection. To examine whether the expression of the proteins is specific for lung cancer, immunological analyses were performed both in lung and non-lung cancer cell lines. In immunostaining and Western blotting, the expression of A2/B1 was observed not only in the lung cancer cells but also in non-lung cancer cells. The expression of hnRNP A2/B1 is not specific for lung cancer and quantitative determination of A2/B1 is required to elucidate their significance in carcinogenesis.

Topographical analysis of p53 expression and DNA ploidy in early bronchial squamous cell carcinoma and preneoplastic lesions.

The significance of p53 mutations and DNA aneuploidy in carcinoma cells has been investigated on the basis of a multi-step development theory of carcinogenesis. It has, however, not been determined whether these alterations can be used as diagnostic markers for the early detection of bronchial squamous cell carcinoma (BSqCC). To address this problem, we topographically investigated p53 alterations and DNA aneuploidy in 24 X-ray-negative, early BSqCC patients with various preneoplastic lesions and in 25 non-carcinoma patients with preneoplastic lesions. Bronchial lesions (n=88) were morphologically classified as hyperplasia (HP, n=5), squamous metaplasia (SM, n=23), low-grade dysplasia (LGD, n=14), high-grade dysplasia (HGD, n=11), intraepithelial carcinoma including 'carcinoma in situ' (CIS) (IEC, n=15), and microinvasive carcinoma (MIC, n=20). Immunohistochemistry for the p53 protein and image cytometry for DNA ploidy detection were performed in serial sections of each lesion. Overexpression of p53 protein was detected in 36, 73, and 65% of the HGD, IEC, and MIC lesions, respectively. Aneuploid DNA profiles were found only in carcinoma lesions, 33% in IEC and 85% in MIC. The topographical analysis revealed two types of early BSqCCs, one with adjacent preneoplastic lesions (sequential type, n=8) and another without such lesions (de novo type, n=16). The p53 protein was frequently overexpressed in both types (sequential type, 79%; de novo type, 62%). In the sequential type, however, the p53 protein was overexpressed in HGD lesions that were directly adjacent to p53-overexpressing carcinoma lesions without exception. The present topographical study suggests that p53 mutations play an important role in the carcinogenesis of BSqCC and that p53-overexpressing HGD lesions in sequential types should be regarded as 'truly' preneoplastic lesions that actually develop into carcinomas. In addition, our study demonstrated that DNA aneuploidy might occur at times after p53 alteration with increasing frequency, as invasive growth begins. Such combination analysis of p53 immunohistochemistry and nuclear DNA ploidy in routine histology may contribute to estimates of malignant potential in preneoplastic and intraepithelial squamous lesions and provide additional information for early detection of BSqCC.

Activation of the nuclear oncogenes N-myc and c-jun in carcinoid [correction of cartinoid] tumors of transgenic mice carrying the human adenovirus type 12 E1 region gene.

The adenovirus (Ad) E1 region genes, E1A and E1B, are well known cooperatively to transform primary rodent cells and activate a number of cellular promoters, including nuclear oncogenes such as N-myc and c-jun, in transfected cell lines. However, there is still less information available on the in vivo mechanism(s) by which the E1 region gene, when chromosomally integrated in the living animals, exerts its effect on nuclear oncogene activation coupled with transformation. To investigate such in vivo activity of E1A we have used a series of microinjection experiments into fertilized eggs to generate three transgenic mice carrying the Ad12-type E1A/E1B genes under the control of the human renin gene. This transgene caused an early onset of bowel cartinoid tumors that express neural cell adhesion molecules, but do not metastasize to any region. Northern blot analysis revealed that the transgenes were considerably expressed in the tumors, but not in other tissues at detectable levels. Interestingly, the levels of N-myc and c-jun mRNAs in the cartinoid tumors were elevated 19- and 8-fold, respectively, as compared with those found in the control intestine. In contrast, the major histocompatibility complex (MHC) class I mRNA level was not altered between the tumor and control intestines, suggesting that this unchanged expression may reflect the loss of tumor metastasis. These findings provide the first in vivo evidence that the expression of the Ad12 E1 region gene induces cartinoid tumors associated with the activation of the nuclear oncogenes N-myc and c-jun.

Immunohistochemical study of the hnRNP A2 and B1 in the rat forebrain.

Immunohistochemical techniques were employed to examine the distribution of RNA-binding proteins A2 and B1 in the rat forebrain. Intense A2 and B1 immunolabeling were observed in the nucleoplasm of the neurons in the cerebral cortices, hippocampal formation, olfactory regions, caudate-putamen as well as the supraoptic nucleus of hypothalamus. In contrast, within the bed nucleus of the stria terminalis, as well as the medial and lateral habenular nucleus of thalamus, immunoreactivity for both proteins was weak. Within the globus pallidus and thalamic nucleus immunoreactivity for A2 was hardly detectable despite of intense B1 immunolabeling, while within the endopiriform nucleus and lateral and basolateral nucleus of amygdala intensity of B1 immunolabeling was relatively weak compared to A2. Our study suggests that the distribution of A2 and B1 are not constant throughout the forebrain and this diversity may reflect the post-transcriptional regulation of cell-specific gene expression of neuronal cells.

The effect of TNP-470 on cell proliferation and urokinase-type plasminogen activator and its inhibitor in human lung cancer cell lines.

The plasminogen activator system has been found to modulate neoplastic spread and angiogenesis in tumors. An angiogenesis inhibitor, TNP-470, has been shown to possess potent antitumor activities in various types of cancer cells. We therefore investigated the inhibitory effect of TNP-470 on cancer cell proliferation, and the suppressive effect of TNP-470 on urokinase-type plasminogen activator (u-PA) and its inhibitor (PAI-1), in human lung cancer cell lines in vitro. TNP-470 inhibited cell proliferation in a dose-dependent manner in both cell lines. u-PA and PAI-1 in culture supernatants were suppressed with the concentrations of TNP-470, in association with a decrease in viable cancer cells. Unchanged serum levels of u-PA and PAI-1 would be of great advantage to the diseased patients, since the plasminogen activator system has a crucial function in the process of distant metastasis.

Imbalance between apoptosis and telomerase activity in myelodysplastic syndromes: possible role in ineffective hemopoiesis.

The myelodysplastic syndromes (MDS) are a group of disorders characterized by peripheral pancytopenia despite normo- or hyper-cellular bone marrow. This is thought to be due to apoptosis of hematopoietic bone marrow cells, resulting in ineffective hematopoiesis. The heterogeneous nuclear ribonucleoprotein (hnRNP) B1 is involved in pre-mRNA processing and binds to telomeric cDNA repeats. The hnRNP B1 is a marker for early cancer. The aim of our study was to clarify the relationships between prognosis and apoptosis, telomerase activity (TA) and hnRNP expression in the bone marrow. The subjects were 51 patients with MDS, including patients with refractory anemia (RA) (n = 32), refractory anemia with ringed sideroblasts (RARS) (n = 1), refractory anemia with excess blasts (RAEB) (n = 7), refractory anemia with excess blasts in transformation (RAEB-t) (n = 8) and chronic myelomonocytic leukemia (CMMoL) (n = 3). We also studied 6 cases with acute myelogenous leukemia (AML) arising from MDS (AML-MDS) and 10 control subjects. Bone marrow biopsies were stained immunohistochemically for caspase-3 (marker of apoptotic activity) and human telomerase reverse transcriptase (hTERT), and hnRNP B1. Fatal pancytopenia was the cause of death in 19 of the 51 patients. The caspase-3 positive cell rate was higher in MDS (16.3%) than in controls (4.4%) and AML-MDS (0.5%). The percentage of hnRNP B1-positive cells was higher in MDS (15.3%) and AML-MDS (56.3%) than in controls (5.6%). In MDS, hnRNP B1 levels were higher in RAEB and RAEB-t subtypes than in RA and RARS. The percentage of hTERT-positive cells was higher in AML-MDS (50.0%) than in controls (20.2%) and MDS (23.6%). Our findings suggest that activation of apoptosis occurs in MDS in the absence of hTERT expression, implicating high apoptosis in the absence of high TA with ineffective hematopoiesis. Poor prognosis correlated with higher caspase-3 and lower hTERT rates. In MDS, hnRNP B1 activity may be associated with leukemic transformation.

Breast cancer shortly after the diagnosis of interstitial pneumonia associated with polymyositis.

Polymyositis is sometimes associated with pulmonary fibrosis or malignant diseases, however, rarely with both simultaneously. For such patients, no criterion for initial treatment and tapering of steroid has been reported. We describe a patient who had breast cancer and interstitial pneumonia associated with polymyositis. In this case, slow tapering of the steroid was an important aspect of the treatment, and close clinical follow-up was necessary to monitor for disease exacerbation.

Long-term cure of a malignant lymphoma of the pleural cavity treated by irradiation.

Malignant lymphomas arise in the pleura in association with a long-standing chronic tuberculous pyothorax. We report a case of a non-Hodgkin's lymphoma of the pleural cavity, inoperable because of local invasion into thoracic wall, who has survived more than 6 years without recurrence. This patient represents the longest reported survival after radiation therapy alone. Radiotherapy holds an important role in the treatment of locally advanced lymphoma of the pleural cavity.

Does earlier detection of lung cancer on mass screening improve outcome in younger and middle-age patients?

In order to demonstrate clinicopathological features, especially in relation to the detection of lung cancer in younger (<40 years) and middle-aged patients, a total of 850 patients with lung cancer were analyzed with reference to their basis for detection. Asymptomatic patients in their forties and fifties diagnosed on mass screening had higher prevalence rate of surgically resectable disease and better three-year survival compared with patients who required medical attention because of symptoms. Our results suggest that mass screening for patients under the age of 50 years does not change the outcome, however, patients in the age group 50-59 years receive some benefit in our screening system.

Lung cancer in middle-aged patients.

Clinicopathological features of middle-aged lung cancer patients were investigated in 1016 consecutive patients. Among them, 22.8% of patients were in their forties and fifties. The preponderance of adenocarcinomas and the higher female/male ratio in middle-aged groups compared with the older group were findings similar to those observed in younger patients. Smoking habit increased according to the age groups. Middle-aged patients had a propensity for advanced stage, however, survival was not inferior to younger patients. Middle-aged patients consisted of two different groups of patients, whose characteristics were similar to those observed in either younger or elderly patients.