Establishment of lung cancer cell line producing parathyroid hormone-related protein

Parathyroid hormone-related protein (PTHrP) producing cell line (KCC-C1) was established from malignant pleural effusion of a patient with squamous cell lung carcinoma. Hypercalcemia and granulocytosis were noted in the patient. The serum level of PTHrP, measured by N-terminal specific radioimmunoassay, was 110 pg/ml (normal < 20 pg/ml). The established KCC-C1 tumor cells proved to have PTHrP RNA transcripts and produce a large amount of PTHrP. Besides the production of PTHrP, the culture medium contained a significant level of interleukin 1 (IL-1). However, tumor necrosis factor or colony stimulating factor was not defected. Transplantation of KCC-C1 tumor cells into nude mice resulted in tumor formation with hypercalcemia. As IL-1 is also known to have bone-resorbing activity, KCC-C1 which may prove valuable in the study of the interaction between PTHrP and IL-1 for induction of hypercalcemia.

The effect of caloric restriction on the lateral diffusion constant of hepatocyte membrane proteins in C57BL/6 male mice of different ages: FRAP studies on liver smears

The lateral mobility of proteins in hepatocyte plasma membranes was compared in calorically restricted and ad libitum (AL)-fed C57BL/6 male mice in age groups from 7 to 28 months. Caloric restriction was achieved by means of the every-other-day (EOD) feeding regimen, maintained for various periods from 1 to 15 months. Protein lateral diffusion constant (D) in hepatocyte membranes was measured by means of fluorescence recovery after photobleaching (FRAP) in liver smears. The peroxide-induced autofluorescence (PIAF) was utilized as a fluorescent label. A mild (1 mM for 10 min) H2O2 treatment of liver smears produces oxidation of riboflavin that is bound to all proteins of the cell membrane. Using this technique, the average lateral diffusion constant (D) and the fractional recovery (FR) of these proteins can be measured. EOD feeding resulted in a significant decrease in body weights and also a significant increase in the values of D in all age groups after 1 month of EOD feeding. After 3.5 months of EOD feeding a further increase of D was observed (up to about 15%). Nevertheless no further change in D occurred if the EOD feeding was maintained for 6.5 or even 15 months. The negative linear age correlation of D observed in the AL-fed animals was present also under the EOD feeding; however, the whole regression equation shifted towards higher values. These experiments indicate that caloric restriction influences the lateral diffusion constant of membrane proteins in hepatocytes. The results are interpreted as a result of an increased protein turnover caused by the caloric restriction.

Expression of highly polysialylated neural cell adhesion molecule in calcitonin-producing cells

Calcitonin-producing cells are endocrine derivatives of the neural crest and have several neuron-like properties. Expression of the neural cell adhesion molecule in calcitonin-producing cells was examined using two types of antibodies to neural cell adhesion molecule: monoclonal antibody 12E3 recognizes the polysialic acid portion of highly polysialylated neural cell adhesion molecule, and monoclonal antibody AF11 and polyclonal antiserum react with the polypeptide portion common to three major isoforms of neural cell adhesion molecule. An immunohistochemical study revealed that highly polysialylated neural cell adhesion molecule was expressed both in fetal rat thyroidal calcitonin-producing cells and in a calcitonin-producing cell line, rMTC 6-23, established from explantable neoplasm of rat calcitonin-producing cells. The neural cell adhesion molecule in the rMTC 6-23 cells was further characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis. Two anti-neural cell adhesion molecule monoclonal antibodies, 12E3 and AF11, revealed a broad positive band around 200,000-250,000 mol. wt in solubilized proteins. When the polysialic acids were eliminated by neuraminidase treatment, the immunoreactivity to monoclonal antibody 12E3 was completely abolished, and core polypeptide corresponding to neural cell adhesion molecule with a molecular weight of 120,000 was detected by monoclonal antibody AF11. These results suggest that cells of the calcitonin-producing cell line express on their surfaces highly polysialylated 120,000 mol. wt form of neural cell adhesion molecule polypeptide.

Detection and characterization of blocking-type anti-acetylcholine receptor antibodies in sera from patients with myasthenia gravis

We developed a highly sensitive, convenient assay for measuring blocking-type anti-acetylcholine receptor antibodies, which inhibit the binding of 125I-labeled alpha-bungarotoxin (alpha-BuTx) to the acetylcholine receptor (AChR). This procedure detected inhibitory activities in sera from 76% of patients with myasthenia gravis. Results of an experiment done with synthetic peptide corresponding to the alpha-BuTx binding region in the alpha-subunit of Torpedo AChR suggested that this inhibition is due to nonspecific steric hindrance caused by the binding of antibodies to a region other than the alpha-BuTx site, rather than by direct binding to the latter site. The inhibitory activities of the blocking-type antibodies and the titers of non-blocking-type antibodies were correlated. Moreover, the blocking-type antibodies could dissociate 125I-labeled alpha-BuTx from 125I-labeled alpha-BuTx-human AChR complex, and their dissociation activities showed good correlation with the inhibitory activities.

Detection and characterization of blocking-type anti-acetylcholine receptor antibodies in sera from patients with myasthenia gravis

We developed a highly sensitive, convenient assay for measuring blocking-type anti-acetylcholine receptor antibodies, which inhibit the binding of 125I-labeled alpha-bungarotoxin (alpha-BuTx) to the acetylcholine receptor (AChR). This procedure detected inhibitory activities in sera from 76% of patients with myasthenia gravis. Results of an experiment done with synthetic peptide corresponding to the alpha-BuTx binding region in the alpha-subunit of Torpedo AChR suggested that this inhibition is due to nonspecific steric hindrance caused by the binding of antibodies to a region other than the alpha-BuTx site, rather than by direct binding to the latter site. The inhibitory activities of the blocking-type antibodies and the titers of non-blocking-type antibodies were correlated. Moreover, the blocking-type antibodies could dissociate 125I-labeled alpha-BuTx from 125I-labeled alpha-BuTx-human AChR complex, and their dissociation activities showed good correlation with the inhibitory activities.

Adaptive changes in zonation for gluconeogenic capacity in liver lobules of cold-exposed rats

The rate of gluconeogenesis from lactate increased in perfused livers after exposure of rats to cold for 5 days, and it returned to the control rate after 20 days [M. Shiota, T. Tanaka, and T. Sugano. Am. J. Physiol. 249 (Endocrinol. Metab. 12): E281-E286, 1985.]. The relationship between the increased gluconeogenic activity and its zonal distribution in liver lobules was studied in cold-exposed rats that had been starved for 24 h by examination of preparations enriched for periportal hepatocytes (PP-H) and for perivenous hepatocytes (PV-H), which had been isolated by the digitonin-collagenase perfusion technique. In the control group, the rate of gluconeogenesis from lactate or alanine was three times higher in PP-H than in PV-H. The rate of gluconeogenesis from these substrates in PP-H was not changed by exposure of rats to cold. The rates of PV-H increased to the level in PP-H after 5 days of exposure of rats to cold and then returned to the control rates after 20 days. The rate of gluconeogenesis from fructose was not altered in either preparation of cells by cold treatment of rats. The change in gluconeogenic capacity in PV-H caused by exposure of rats to cold was unrelated to changes in the activity of the malate-aspartate shuttle and of pyruvate kinase. The increased capacity in mitochondrial respiration was observed in both preparations of cells by cold treatment of rats for 5 days. The activity of phosphoenolpyruvate carboxykinase was higher in PP-H than in PV-H in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvant chemotherapy for completely resected stage III non-small-cell lung cancer. Results of a randomized prospective study. The Japan Clinical Oncology Group

Two hundred nine patients with completely resected stage III non-small-cell lung cancer were randomized to receive postoperative cisplatin and vindesine chemotherapy or no further treatment. Before randomization, patients were stratified by the histologic characteristics of their tumors (squamous versus nonsquamous cell carcinoma). Prognostic variables such as histology, performance status, extent of operation, and tumor and nodal status of the eligible patients in chemotherapy (n = 90) and control groups (n = 91) were equally distributed. There was no statistically significant difference in disease-free and overall survival between the two groups. The 3-year disease-free survivals of the chemotherapy and control groups were 37% and 42%, respectively. The median survival times (5-year survival) were 31 months (35%) in the chemotherapy group and 37 months (41%) in the control group. These was no different pattern in the first site of recurrence (local versus systemic) between the two groups. This study failed to demonstrate the therapeutic benefits of postoperative cisplatin and vindesine chemotherapy.

Taurine conjugate of ursodeoxycholate plays a major role in the hepatoprotective effect against cholestasis induced by taurochenodeoxycholate in rats

Rats which were taurine-deprived through beta-alanine administration and untreated rats were used to elucidate the mechanism of hepatoprotective effects of ursodeoxycholate (UDC). Animals were infused with taurochenodeoxycholate (TCDC, 0.4 mumol.min-1.100 g-1) alone or in combination with tauroursodeoxycholate (TUDC), or with UDC (both 0.6 mumol.min-1.100 g-1) for 2 h. Ursodeoxycholate as well as TUDC prevented severe cholestasis and liver damage induced by TCDC infusion in both untreated and taurine-deprived rat groups. In untreated rats, however, UDC was less effective in hepatoprotection than TUDC as indicated by sequential changes in biliary LDH output during the period of 30 to 120 min (P < 0.05). In rats receiving UDC and TCDC, total biliary output of LDH for 2 h was significantly higher in taurine-deprived rats than that in the control (73.40 +/- 10.10 vs 41.14 +/- 12.56: P < 0.05), suggesting that the difference became greater upon taurine deprivation. In contrast, in rats receiving TUDC and TCDC, the protective effect was comparable for the taurine-deprived and untreated rats. When the animals were infused with UDC and TCDC, taurine-deprived rats exhibited a biliary excretion rate for TUDC half that of control rats (P < 0.05). Furthermore, a highly significant correlation was observed between the biliary excretion rate of TUDC and biliary output of LDH (r = -0.886, P < 0.0001). These results suggest that UDC conjugates, especially TUDC, and not UDC may play a major role in the prevention of cholestasis and liver cell damage caused by TCDC infusion.

Laparoscopic oversewing of a bleeding Mallory-Weiss tear under endoscopic guidance

Continuous bleeding from a Mallory-Weiss tear required laparoscopic surgery to halt the bleeding. The oversewing of the laceration at the esophagogastric junction was readily performed under video control with endoscopic guidance and the bleeding ceased. To stop bleeding from such a tear, we prefer to use this modern approach.

Two truncated forms of rat insulin receptor-related receptor

The insulin receptor-related receptor (IRR) (1271 amino acids) is expected to have unique functions as a novel member of the insulin receptor family. In this paper, we report two alternatively spliced variants of rat IRR mRNA, which are predicted to encode two truncated forms of IRR, sIRR-1 (410 amino acids) and sIRR-2 (469 amino acids). The amino acid sequence of sIRR-1 is identical to the N-terminal 410-amino acid sequence of IRR. sIRR-2 has an additional 59-amino acid insertion in the C-terminal region. Both truncated forms retain the N-terminal and cysteine-rich domains but lack the transmembrane and intracellular tyrosine kinase domains, indicating that the truncated forms are the secreted forms. The translation products of the truncated form mRNAs were detected in the stomach and kidney by Western analysis. However, the physiological significance of the secreted forms remains to be elucidated.

Cloning, expression and characterization of horse L-ferritin in Escherichia coli

Horse L-ferritin cDNA was cloned from horse liver, and the base sequence was determined. The L-ferritin was expressed using pTZ18U encoding lac promoter, and found to possess an additional 8-amino acid sequence at the N-terminus as compared with commercially obtained horse spleen (natural) ferritin. It was determined that there was Pro at position 94 in both the recombinant and natural L-ferritin, although it was previously reported that Leu was in this position in the natural species. Transmission electron microscopy showed that this recombinant ferritin formed a 24-mer shell.

Nicotinic acetylcholine receptor mRNAs in myasthenic thymuses: association with intrathymic pathogenesis of myasthenia gravis

Reverse transcription and the polymerase chain reaction showed that the alpha-, beta- and gamma-subunit genes of nicotinic acetylcholine receptor (AChR) in human skeletal muscle were expressed in myasthenia gravis (MG) thymuses (3 thymomas and 7 hyperplastic thymuses). A study of the expression of these subunit mRNAs in a variety of human tissues showed that alpha-subunit mRNA was expressed in human thymus and cerebral cortex, and that all three subunits were expressed only in human child thymus. Our results suggest that a complete AChR similar to extrajunctional (embryonic) muscle AChR is expressed in MG thymuses and that intrathymic AChR might be the primary antigen which induces autoimmune responses to muscle AChR.

Enhancement of extracapsular polysaccharide synthesis in Klebsiella pneumoniae by RmpA2, which shows homology to NtrC and FixJ

We determined the complete nucleotide sequence of a 2.1-kb HindIII-EcoRI fragment that was cloned from a resident large plasmid of Klebsiella pneumoniae Chedid, a highly virulent and mucoviscous strain of the O1:K2 serotype. This fragment encoded an ability to enhance K2 capsular polysaccharide synthesis in K. pneumoniae, and a 636-bp open reading frame (rmpA2) was found. The 411-bp rmpA reported to be involved in the virulence and mucoid phenotypes of K. pneumoniae by Nassif et al. (Mol. Microbiol. 3:1349-1359, 1989) was a part of rmpA2. Eighty percent homology in nucleotide sequence was found between rmpA2 and rmpA in the corresponding regions. The central domain of the deduced amino acid sequence of RmpA2 showed considerable homology to the central domains of NtrC of K. pneumoniae and Escherichia coli, to which the sigma factor of RNA polymerase binds. The C-terminal domain of RmpA2 also demonstrated considerable homology with the putative helix-turn-helix motifs of LuxR of Vibrio fischeri and FixJ of Rhizobium meliloti. Moreover, RmpA2 also showed some homology in its N- and C-terminal regions to those of RcsA, a transcriptional activator for colanic acid synthesis in E. coli. On the other hand, a sequence upstream of rmpA2 was found to be highly homologous to insertion sequence 3 of members of the family Enterobacteriaceae. Southern hybridization analysis suggested that rmpA2 exists on the large plasmids of all mucoviscous virulent K2 strains but not on those of the slightly mucoviscous avirulent strains. Freeze substitution electron microscopy and fluorescent-antibody staining with anti-K2 serum revealed that K. pneumoniae Chedid has a dense and thick capsule (180 nm) with dense extracapsular substance, whereas K. pneumoniae K2-215, one of the slightly mucoviscous and avirulent strains, has a capsule which is looser and thinner (120 nm) than that of strain Chedid and no extracapsular substance. Introduction of rmpA2 into K2-215 as well as reference strains K. pneumoniae K9 and K72 resulted in a change of the colony phenotype to highly mucoviscous through abundant production of extracapsular substance which reacted with anti-K2, -K9, or -K72, respectively, as did their parental strains. From these results, it is suggested that RmpA2 belongs to the family of transcriptional regulators and confers a highly mucoviscous phenotype on cells of various serotypes of K. pneumoniae by enhancing extracapsular polysaccharide synthesis.

Conversion of a NADPH-dependent aldehyde reducing enzyme into aldose reductase

1. Aldose reductase, aldehyde reductase and high-Km aldose reductase were purified from the inner medulla of dog kidney. 2. Compared with aldose reductase, high-Km aldose reductase had a lower isoelectric point, a lower activity for aldo-sugars and a lower sensitivity for aldose reductase inhibitors, and it was not activated by sulfate ions. Both reductases had the same molecular weight (38,500) and immunochemical properties. 3. High-Km aldose reductase was easily converted into an aldose reductase-like enzyme, namely a generated reductase upon incubation in neutral buffer solution. 4. The generated reductase was identical with aldose reductase with respect to the isoelectric point, substrate specificity, activation by sulfate ions and IC50 values for aldose reductase inhibitors. The generated reductase revealed immunochemical identity with aldose reductase as well as high-Km aldose reductase.

Isolation of rfb gene clusters directing the synthesis of O polysaccharides consisting of mannose homopolymers and serological analysis of lipopolysaccharides

Four serotypes of two genera, Escherichia coli O8 and O9 and Klebsiella O3 and O5, produce the O polysaccharides consisting of mannose homopolymers. Previously, we reported the isolation and expression of E. coli O9 rfb in E. coli K-12 strains (Kido et al, J. Bacteriol., 171: 3629-3633, 1989). In this study, R' plasmids carrying his-rfb region of the other three strains were isolated and expressed in E. coli K-12 strain. Serological study of lipopolysaccharides (LPS) synthesized in E. coli K-12 strain was carried out. His-linked rfb genes from E. coli O9 and Klebsiella O3 directed the synthesis of O polysaccharides with the same antigenicity as those of the parental strains in E. coli K-12 strain. On the other hand, rfb genes from E. coli O8 and Klebsiella O5 directed the synthesis of O polysaccharides which were antigenically not identical but partially common to those of the parental strains. A rough strain derived from E. coli O8 synthesized LPS which showed the identical antigenicity as the wild strain when the his-rfb region of E. coli O8 was introduced. The results suggest that some genes located distantly from his are additionally required to complete the synthesis of O polysaccharides of E. coli O8 and Klebsiella O5.

Brefeldin A blocks the cytotoxicity of T cell receptor alpha/beta and gamma/delta cytotoxic T lymphocyte clones reacting against human autologous cancer cells

We studied the effector mechanism of T cell receptor (TCR) alpha/beta- and gamma/delta-type cytotoxic T lymphocyte (CTL) clones that react with human autologous tumor cells. Treatment of tumor cells with a fungal antibacterial reagent, brefeldin A (BFA), resulted in the inhibition of cytotoxicity of an autologous tumor (HST-2)-specific CD8+ TCR alpha/beta-type CTL, TcHST-2. Other anti-metabolites such as chloroquine, cycloheximide and colchicine did not affect the cytotoxicity. The cell-surface antigen expression, including MHC class I molecules, was not influenced by BFA treatment. Furthermore, BFA did not influence the cytotoxicity of lymphokine-activated killer cells and natural killer cells. Since BFA blocks the transport of peptides from endoplasmic reticulum to the Golgi apparatus, the above data suggest that BFA could affect washing out of the peptide fragments from the MHC class I groove. Consequently, target tumor cells were protected from killing by CTL. Moreover, we obtained a CD4-, 8-, TCR gamma/delta-type (V delta 1+) CTL clone, TcHOT, that reacts against an autologous ovarial carcinoma, HOT. BFA could also inhibit this cytotoxicity, and it is likely that different presenting molecules other than MHC class I proteins participate in the cytotoxicity of this TCR gamma/delta-type CTL. These studies suggest that both TCR alpha/beta- and gamma/delta-type CTL may require antigenic peptides that are most likely derived from the BFA-sensitive, intracellular endogenous target proteins.

Central effects of interleukin-1 on blood pressure, thermogenesis, and the release of vasopressin, ACTH, and atrial natriuretic peptide

To assess the central role of interleukin 1-beta (IL-1 beta) in the release of ACTH, vasopressin (AVP) and atrial natriuretic peptide (ANP) and in the regulation of blood pressure and thermogenesis, 3 ng (0.173 pM) x 100-1 x BW-1 (LIL), 30 ng (1.73 pM) x 100g-1 x BW-1 (MIL), and 150 ng (8.63 pM) x 100g-1 x BW-1 (HIL) of human IL-1 beta dissolved in sterile saline were injected intracerebroventricularly to conscious rats. In the control rats, saline alone (5 microliters) was administered. In three other groups, rats were pretreated with indomethacin, a cyclooxygenase inhibitor, given i.v. (1 mg x 100g-1 x BW-1); medium and high doses of IL-1 beta or its vehicle were given. In the LIL group, IL-1 beta increased blood pressure, body temperature and plasma AVP and ANP without any changes in heart rate (HR) and plasma ACTH. In the MIL group, plasma ACTH was increased, and changes in the other parameters were similar to those in the LIL group. In the HIL group, however, the pressor and thermogenetic responses were attenuated; plasma AVP, ACTH, and ANP were increased; and HR was unchanged. In the control (CON) group, none of these parameters was changed throughout the studies. Indomethacin abolished the AVP and ACTH responses to IL-1 beta, but potentiated the pressor and hypothermic responses and increased plasma ANP. These data suggest that the actions of IL-1 beta on AVP and ACTH release and thermogenesis, but not on blood pressure and the release of ANP, are modulated by the stimulated central production of prostaglandins.

[Double blind controlled study of ubenimex (Bestatin) against squamous cell lung cancer--a multicenter cooperative study]

To investigate effects of the combination of ubenimex, chemotherapy, and radiotherapy against unresectable advanced squamous cell carcinoma of the lung, a placebo controlled double-blind study was performed. Of 365 registered cases, there were 258 cases in the complete radiation group in which the treatment as specified in the protocol (irradiation of 40 Gy or more to the thorax subsequent to chemotherapy) was conducted; the 50% survival time was 449 days and 363 days in the ubenimex group and the placebo group, respectively. A significant (p = 0.0473) prolongation of the survival time was noted in the ubenimex group, and the response rate was 60.9% and 50.0% (p = 0.087). From these results it was confirmed that ubenimex, when used in combination with chemotherapy and radiotherapy, not only enhances the tumor-reducing effect but also prolongs the survival time.

Responses to catecholamines in perfused livers of hypothalamic-lesioned rats

The responses of hepatic glycogenolysis to catecholamines in ventromedial hypothalamus (VMH)-lesioned male rats were examined in perfused livers. Seven days after bilateral electrical lesioning of the VMH, the livers were perfused. Isoproterenol, a beta-agonist, stimulated greater glucose production in VMH-lesioned rats than in controls (32.8 vs. 5.6 mumol glucose.h-1.g liver-1), while responses to phenylephrine, an alpha-agonist, decreased significantly compared with controls (44.4 vs. 69.8 mumol glucose.h-1.g liver-1). There were no significant differences in responses of livers to glucagon and vasopressin between control and VMH-lesioned rats. Adrenodemedullation showed the same effect on beta-responses as lesions in the VMH, but no effect on alpha-responses. Plasma epinephrine levels were not detectable with the high-performance liquid chromatography analysis in VMH-lesioned rats. The periodicity of plasma corticosterone levels was observed in both VMH-lesioned and control rats, although daytime increases in plasma corticosterone were blocked by VMH lesions. These results suggest that the lesions in the VMH cause changes in the levels of adrenergic receptor and that the increase in beta-responses is caused mostly by the reduction of plasma epinephrine.

Role of vagal nerves and atrial natriuretic hormone in vasopressin release and a diuresis under hypertonic volume expansion

To assess whether increases in circulating atrial natriuretic hormone (ANH) in response to the plasma volume expansion, besides the volume receptor-mediated mechanisms, attenuate the arginine vasopressin (AVP) response to increased plasma osmolality and whether changes in plasma AVP and ANH affect renal solute excretion under hypertonic plasma volume expansion, hypertonic saline (0.95 mol/l saline) alone, hypertonic saline with 6% dextran (6D-HS) and hypertonic saline with 9% dextran (9D-HS) were administered into anesthetized dogs. In the control study, 0.15 mol/l NaCl alone was administered. Plasma AVP and ANH and cardiovascular and renal functions were determined. Hypertonic saline and 9D-HS also were administered into the vagotomized and sham operated dogs, and the same parameters were determined. Mean blood pressure and heart rate never changed in all the groups, but central venous pressure and plasma volume increased markedly in 6D-HS and 9D-HS groups. In the control and hypertonic saline groups, central venous pressure increased slightly but plasma volume never changed. Plasma AVP increased in the order of hypertonic saline, 6D-HS and 9D-HS, but plasma ANH increased in reverse order. Vagotomy restored the AVP response to 9D-HS to 75% of its response to hypertonic saline, with a marked rise in plasma ANH. Urine sodium and potassium excretion and urine flow increased in hypertonic saline, 6D-HS and 9D-HS groups, but these increases were comparable among the groups. In the control group, these parameters never changed. These results suggest that the volume receptor-mediated vagal neural and ANH responses to the plasma volume expansion may have an effect on the suppression of the AVP response to osmotic stimuli, and increased plasma ANH release never potentiated the natriuresis under the hypertonic plasma volume expansion.

Is T factor of the TNM staging system a predominant prognostic factor in pathologic stage I non-small-cell lung cancer ? A multivariate prognostic factor analysis of 151 patients

We attempted to clarify whether the T factor of the TNM staging system should be viewed as a predominant prognostic factor in patients with pathologic stage I non-small-cell lung cancer when analyzed together with various histopathologic factors and deoxyribonucleic acid ploidy pattern of tumors. We studied 151 patients who were in this stage. Histopathologic factors used in the analysis were as follows: histologic cell type (squamous or nonsquamous cell carcinoma), grade of differentiation, and tumor invasion of visceral pleura and vessels. Deoxyribonucleic acid ploidy pattern of tumors was analyzed by flow cytometry, and the tumors were classified as diploid or aneuploid tumors. Significant prognostic factors (p < 0.05) that were demonstrated by univariate analysis of survival curves were as follows: (1) T1 versus T2; (2) well versus moderately or poorly differentiated tumor; (3) the absence versus presence of tumor exposed on pleura, (4) artery invasion, (5) lymphatic vessel invasion; and (6) diploid versus aneuploid tumor. Multivariate prognostic factor analysis showed the grade of differentiation and deoxyribonucleic acid ploidy pattern to be predominant prognostic factors. The T2 tumor group had significantly more cases with tumor invasion of lymphatic vessels that did the T1 tumor group and included 18 cases with tumor exposed on pleura. When these two factors were excluded from multivariate analysis, the T factor was marginally significant (p = 0.08). These observations suggest that the T factor is not necessarily a predominant prognostic factor in pathologic stage I non-small-cell lung cancer.