Transplantation resistance to a Rous sarcoma virus-induced tumor in mice immunized with v-src protein.

It is of great interest in tumor immunology to know whether oncogene products could be used not only as tumor markers for cancer diagnosis, but also as immunogens for cancer therapy. BALB/c mice immunized with syngeneic fibroblasts, Escherichia coli cells producing p60v-src, or the purified p60v-src protein extracted from the E. coli producer cells showed transplantation resistance to a Rous sarcoma virus-induced tumor but not a Kirsten sarcoma virus-induced tumor. In contrast, mice immunized with cells not producing p60v-src or their derived proteins or with chicken ovalbumin did not show any significant resistance. These findings suggest that p60v-src can act as a specific transplantation rejection antigen in mice.

Identification of genes that exhibit increased expression after flat reversion of NIH/3T3 cells transformed by human activated Ha-ras oncogene.

By differential hybridization, we have isolated 14 cDNA clones corresponding to genes that are more highly expressed in the flat revertant cell line R1 than in the parental human Ha-ras oncogene-transformed NIH/3T3 cell line (EJ-NIH/3T3). From cross-hybridization experiments, we determined that 5 sequence families accounted for the 14 clones. DNA sequencing revealed that four out of five selected cDNA clones represented mitochondrial genes (cytochrome b, cytochrome c oxidase subunit II, NADH dehydrogenase subunits 1 and 4, respectively), whereas one cDNA clone was homologous to the alpha 2 (type I collagen gene. Although a Southern blot analysis of the studied cell lines showed similar copy numbers of mitochondrial genomes, the transcript levels of the mitochondrial genes were high in R1, intermediate in NIH/3T3 and low in EJ-NIH/3T3 and partially revertant R2 cell lines. alpha 2 (type I) collagen mRNA levels were high in R1 and NIH/3T3, intermediate in R2 and low in EJ-NIH/3T3 cells. These results suggest that a complex alteration of the expression of mitochondrial and extracellular matrix components may be closely associated with the flat reversion of the transformed cells.

Reduced drug accumulation in a newly established human lung squamous-carcinoma cell line resistant to cis-diamminedichloroplatinum(II).

A human lung squamous-carcinoma cell line resistant to cis-diamminedichloroplatinum(II) (CDDP), designated PC10-B3, has been established from the original cell line PC10 by a stepwise increment of the CDDP concentration. This is the first report, to our knowledge, to establish a CDDP-resistant lung squamous-carcinoma cell line. PC10-B3 has continued to proliferate in the presence of 0.5 micrograms/mL CDDP, whereas PC10 could not survive. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that PC10-B3 was 11.4-fold more resistant to CDDP than PC10 and cross-resistant to diammine(1,1-cyclobutanecarboxylate)platinum(II) (CBDCA) and 254-S, but not to doxorubicin or etoposide. PC10-B3 was characterized by a smaller DNA index and a larger cell size compared to PC10. The level of intracellular platinum accumulation was reduced by about 5- to 8-fold in PC10-B3 when compared with PC10, suggesting that reduced drug accumulation may be one of the important factors in contributing to CDDP resistance in PC10-B3.

Marked reduction of type I keratin (K14) in cisplatin-resistant human lung squamous-carcinoma cell lines.

We have established two cisplatin-resistant human lung squamous-carcinoma cell lines, PC10-B3 and PC10-E5, from their original cell line PC10. To discover which proteins are associated with cisplatin resistance, we carried out a two-dimensional gel electrophoresis to analyze differences in protein alteration between PC10, PC10-B3 and PC10-E5. A protein spot M(r) 50 kDa, pI5.3, was reduced markedly and a spot M(r) 50 kDa, pI4.9 was increased when PC10-B3 and PC10-E5 were compared with PC10. A spot M(r) 58 kDa, pI5.8 newly appeared only in PC10-E5. Cell fractionation showed that the M(r) 50 kDa, pI5.3 (p50-5.3) and the M(r) 50 kDa, pI4.9 fell within the nuclear fraction, while the M(r) 58 kDa, pI5.8 was found among the cytosol and microsomal fractions. Microsequencing after in situ digestion of the dramatically reduced spot p50-5.3 revealed that it was identical to 50 kDa, type I keratin (K14). Moreover, a retinoic acid-mediated K14 reduction was concomitant with a 4.0-fold increase in cisplatin resistance in PC10. Our report is the first to suggest the possible association of marked K14 reduction and cisplatin resistance in PC10-B3 and PC10-E5.

Circumvention of Cisplatin resistance in h-ras transformed-nih/3t3 cells by suppressor mutant of h-ras.

The expression of H-ras oncogene, it has been shown, induces cisplatin resistance in vitro. Using two types of flat revertants (R1, F32/F33) which lost the transformed phenotypes, we studied the mechanism of the cisplatin resistance. R1 cells, which expressed an activated c-H-ras oncogene, exhibited increased cisplatin resistance. Further, F32/F33 cell lines, which were suppressed the H-ras function by a suppressor mutant of H-ras, restored the cisplatin sensitivity. These results implicate that the cisplatin resistance was directly related to the expression of H-ras and can be circumvented by suppression of the H-ras functions.

Frequent cyclin D1 expression in chromate-induced lung cancers.

Ex-chromate workers are frequently afflicted with lung cancers, especially central-type squamous cell carcinomas (SCCs) of the lung. However, little is known about the molecular and cellular biologic characteristics of chromate-induced lung cancers. We investigated expression of cyclin D1, bcl-2, and p53 proteins in chromate-induced lung cancers by immunohistochemistry, compared with those in lung cancers from nonexposed individuals and those in individuals with pneumoconiosis. Of 19 chromate-induced lung cancers, 16 tumors were SCCs, including 11 central and 5 peripheral types. Eleven (69%) of 16 chromate SCCs showed cyclin D1 expression. In contrast, cyclin D1 expression was observed in only 3 (12%) of 26 SCCs from nonexposed individuals and 6 (16%) of 37 SCCs that developed in patients with pneumoconiosis, respectively. The frequency of cyclin D1 expression proved to be significantly higher in chromate-induced SCCs than in SCCs from nonexposed individuals and from those with pneumoconiosis (P < .001). When comparisons were extended to all histologic types of lung cancer, cyclin D1 expression was observed significantly more often in chromate-induced lung cancers than in lung cancers from nonexposed subjects and those from patients with pneumoconiosis (11 [58%] of 19 v 5 [10%] of 52, P < .001, and 7 [11%] of 63, P < .001, respectively). Frequencies of bcl-2 and p53 expression were not significantly different among lung cancers from ex-chromate workers, nonexposed individuals and those with pneumoconiosis. The current study suggests that cyclin D1 expression may be involved in the development of chromate-induced lung cancers, although its underlying mechanism remains to be determined.

[Establishment and characterization of human lung squamous-carcinoma sublines resistant to cis-diamminedichloroplatinum (II)].

I have established human lung squamous-carcinoma cell lines resistant to cis-Diamminedichloroplatinum (II) (CDDP), designated PC10-B3 and PC10-E5, from the original cell line PC10, by a stepwise increment of CDDP concentration. An MMT assay revealed that PC10-B3 was 11.4-fold, and PC10-E5 was 19.9-fold more resistant to CDDP than PC10, respectively. PC10-B3 was cross-resistant to CBDCA and 254-S, but not to doxorubicin and etoposide. The level of intracellular platinum accumulation was reduced by about 5 to 8-fold in PC10-B3 when compared with PC10. A two-dimensional gel electrophoresis was used to analyse the relative amount of proteins as between PC10 and its CDDP resistant sublines. The protein spot MW50 kD, pI5.3 was markedly reduced, and the spot MW50kD, pI4.9 was increased in PC10-B3 and PC10-E5 when compared to PC10. The spot MW58kD, pI5.8 newly appeared only in PC10-E5. I collected the most dramatically changed spot, MW50kD, pI5.3 (50kD-5.3), and processed it to determine its peptide sequence. I found that 50kD-5.3 was identical to 50kD, type I keratin (K14). Moreover, a retinoic acid-mediated K14 reduction was concomitant with a 4.0-fold transient increase in CDDP resistance in PC10. Taken together, the reduced intracellular platinum accumulation and the marked decrease of K14 imply that they are important factors in contributing to CDDP resistance in PC10-B3.

Bronchogenic glomangiomyoma with local intravenous infiltration.

Most glomus tumours occur in the dermis and subcutaneous tissues. Lung glomus tumours are quite rare. The current authors present the first reported case of a lung-derived glomangiomyoma, the rarest variant of glomus tumour. A 56-yr-old female was admitted with haemoptysis. Chest computed tomography showed an approximately 5-cm-diameter mass in the right lower lobe with mucoid impaction. After a right lower lobectomy, a diagnosis of glomangiomyoma was made. The tumour had grown endobronchially and its maximal diameter was 5.5 cm. Although cytologically benign, glomus tumour cells had visibly infiltrated neighbouring vessels. These results suggest that a bronchogenic glomangiomyoma has a low-grade malignancy potential and warrants close follow-up.

[A case report of the pathognomonic relationship between idiopathic interstitial pneumonia and silicosis].

A 67 year-old male complaining of cough and exertional dyspnea was hospitalized for evaluation of an abnormal chest shadow. Chest X-ray films revealed bilateral diffuse nodular shadows, honeycombing in the lower lung fields and pleural thickening suggestive of idiopathic interstitial pneumonia. He had worked as a boilerman and painting using various materials. Transbronchial lung biopsy did not reveal silicotic nodules or asbestos bodies. Analytical electron microscopic study demonstrated amounts of free silica without other elements and asbestos fibers. This case suggests a pathognomonic relationship between idiopathic interstitial pneumonia and silica inhalation.

Bcl-2 expression in non-small cell lung cancers: higher frequency of expression in squamous cell carcinomas with earlier pT status.

Abnormal expression of the bcl-2 gene product (Bcl-2) has been found in a wide variety of tumors, including lung cancer. In the present study, a total of 116 tumor specimens from surgically resected non-small cell lung cancer (NSCLC) patients, that were previously studied for p53 protein expression, were analyzed with immunohistochemistry for Bcl-2 expression. Forty (34%) of 116 tumor specimens showed Bcl-2 expression, which was found to occur more frequently in males than females (p = 0.049) and to be associated with smoking (p = 0.047). Bcl-2 expression was more frequently observed in squamous cell carcinomas (27 of 51, 53%) than in adenocarcinomas (12 of 55, 22%; p = 0.002), and in pT1 tumors (11 of 13, 85%) than in pT2 and pT3 tumors (16 of 38, 42%) in squamous cell carcinomas (p = 0.01). Bcl-2 expression did not correlate either with p53 protein status. We compared Bcl-2 expression in primary tumors and metastatic tumors of regional lymph nodes. Of 11 cases with Bcl-2-negative primary tumors, 10 were Bcl-2-negative in metastatic tumors except 1 case. In contrast, of 10 cases with Bcl-2-positive primary tumors, 6 lost Bcl-2 expression in metastatic tumors, while the remaining 4 cases still showed Bcl-2 expression in metastatic tumors. In the 89 potentially curatively treated patients, those with Bcl-2-positive and Bcl-2-negative tumors did not show a significant difference in survival (5-year survival rates, 56 and 42%, respectively, p = 0.2 by the generalized Wilcoxon test). These data indicate that Bcl-2 expression is frequently observed in squamous cell carcinomas with early pT status, and that it does not predict prognosis of patients with NSCLC.

Elevated gelsolin and alpha-actin expression in a flat revertant R1 of Ha-ras oncogene-transformed NIH/3T3 cells.

Expressions of gelsolin and alpha-actin have been investigated in a revertant cell line R1 and compared with the parental human activated Ha-ras oncogene-transformed NIH/3T3 (EJ-NIH/3T3), untransformed NIH/3T3 and partially revertant R2 cells. Gelsolin mRNA expression was strongest in R1 cells, intermediate in R2 and NIH/3T3 cells, and low in EJ-NIH/3T3 cells. Southern blot analysis gave neither signs of gross rearrangements nor amplification of the gelsolin gene. alpha-actin mRNA expression was restored in R1 cells to the level of NIH/3T3 cells. In R2 and EJ-NIH/3T3 cell lines, no alpha-actin transcript was detected. High gelsolin expression and restoration of alpha-actin expression may be associated with the acquirement of flat morphology and ordered cell growth pattern, which imply loss of tumorigenicity of R1 cells.

A polymorphic DNA marker genetically linked to congenital malformations.

Unusual restriction fragments were detected by DNA blot hybridization with PCNA (DNA polymerase-delta auxiliary protein) probe in one of seven cases of congenital malformations. Chromosomal in situ hybridization localized PCNA gene to region q31-35 of human chromosome 2. To discover the locus more closely associated with congenital malformations, a cloned DNA segment which has been mapped to chromosomal region 2q33-36 was tested for restriction fragment length polymorphisms (RFLPs) in these patients. The 2q33-36 probe hybridized with 2.1-kb, 1.9-kb and 1.7-kb fragments in ten normal control samples. In seven cases of congenital malformations examined, however, the band of 2.1 kb is absent in six cases and the band of 1.7 kb in one case. These results indicate that the locus closely linked to congenital malformations is present in the proximity of PCNA locus.

The relationship of the proliferating cell nuclear antigen protein to cis-diamminedichloroplatinum (II) resistance of a murine leukemia cell line P388/CDDP.

We investigated whether the proliferating cell nuclear antigen (PCNA) protein takes part in cis-diamminedichloroplatinum (II) (CDDP) resistance, using a murine leukemia cell line P388 and its CDDP resistant cell line. P388/CDDP was 4 times more resistant to CDDP than P388. The cell lines were maintained in the DBA/2 female mouse peritoneal space. In total cells, the amount of the PCNA protein decreased to 90% in P388 after 1 h CDDP treatment, but that of P388/CDDP increased to 127%. The difference was statistically significant (p = 0.012, n = 5). As for G2/M phase cells, the difference was also significant at 1 h (p = 0.016, n = 5) and at 2 h (p = 0.036, n = 5) after treatment. In P388 the amount of the PCNA protein decreased in accordance with the inhibited cell proliferation, whereas in P388/CDDP, the amount of the PCNA protein increased in spite of the inhibited cell proliferation. This increase of the PCNA protein suggests that the PCNA protein is involved in CDDP resistance of P388/CDDP through enhanced DNA repair synthesis.

[Clinical study of multiple primary cancers including lung cancer].

Out of a total of 506 lung cancers treated between 1977 to 1988, a total of 27 (5.3%) multiple primary cancers were uncovered. The patients consisted of 20 males and 7 females and their average age was 67 (48-81) years. The frequency seen in the histological type of patient with multiple primary cancers was the same as that seen in their background lung cancers. Twenty-one (78%) patients were smokers. Thirteen patients (45%) had a family history of cancer. Two cases had 3 family members who had a cancer history. The tumor DNA contents of 2 cases with multiple primary cancers were analyzed. In both cases, the DNA indices were found to differ between the first and the second cancer. Thus, it may be possible to identify multiple primary cancers by determining the tumoral DNA content.

p53 and Bcl-2 expression in pneumoconiosis-related pre-cancerous lesions and lung cancers: frequent and preferential p53 expression in pneumoconiotic bronchiolar dysplasias.

To explore the mechanism by which lung cancers excessively arise from pneumoconiosis, we determined the altered expression of p53 and Bcl-2 by immunohistochemistry (IHC) in lung cancers, dysplasias and non-cancerous pulmonary epithelia in pneumoconiotics in comparison with those from non-pneumoconiotic patients. We examined p53 expression in squamous cell carcinomas (SCCs) and dysplasias separately in the central and peripheral zones of bronchial trees, based on observations that SCCs from pneumoconiotic patients occurr more frequently in peripheral epithelia than those from non-pneumoconiotic patients (55 of 72 SCCs with pneumoconiosis vs. 33 of 72 SCCs without pneumoconiosis). Forty-one of 72 patients with pneumoconiosis-related lung cancers had altered p53 expression, which was comparable to the positivity of p53 expression in lung cancers without pneumoconiosis. p53 expression was observed significantly more frequently in bronchiolar dysplasias with pneumoconiosis than in those from non-pneumoconiotic patients (13 of 23 vs. 4 of 22), while p53 expression was found in bronchial dysplasias with pneumoconiosis as frequently as those without pneumoconiosis. Moreover, in patients with pneumoconiosis, bronchiolar dysplasias exhibited p53 expression more frequently than bronchial dysplasias (13 of 23 vs. 4 of 19). When comparison was restricted to bronchiolar dysplasias from patients without lung cancer, p53 expression had a strikingly higher frequency in the dysplasias with pneumoconiosis than in those from non-pneumoconiotic patients (8 of 15 vs. 0 of 14). Bcl-2 occasionally was expressed in squamous metaplasias and basal cell hyperplasias, in contrast to p53, for which immunostaining was negative in these lesions. Altogether, our results show that pre-cancerous and/or cancerous targets in pneumoconiosis may be distributed over a more peripheral zone than those in patients without pneumoconiosis.

Pneumoconiosis-related lung cancers: preferential occurrence from diffuse interstitial fibrosis-type pneumoconiosis.

It has been reported that patients with pneumoconiosis occasionally have a diffuse interstitial fibrosis (DIF) that resembles interstitial pneumonia, but little is known about the relation between pneumoconiosis-associated DIF and the risk of lung cancer. In the present study, we evaluated the incidence of DIF by chest CT and its contribution to lung cancer in 563 patients with nonasbestos pneumoconiosis. Fifty-five (10%) of the 563 patients had DIF. Pneumoconiosis with DIF had an exceedingly high concurrence of lung cancers when compared with pneumoconiosis without DIF (29 [53%] of 55 versus 78 [15%] of 508, p < 0.001). Squamous cell carcinomas (SCCs) of the lung from pneumoconiosis with DIF exclusively comprised peripheral-types, as compared with SCCs from pneumoconiosis without DIF (13 [100%] of 13 versus 33 [72%] of 46, p = 0.03). In addition, lung cancers arose frequently from the area of DIF in pneumoconiosis with DIF (20 [74%] of 27). Furthermore, our pathologic examination revealed that dysplasias from pneumoconiosis with DIF were significantly more frequently observed in peripheral bronchioli than were dysplasias from pneumoconiosis without DIF (11 [69%] of 16 versus 20 [30%] of 66, p = 0.01). p53 expression evaluated by immunohistochemistry was frequently observed in dysplasias from pneumoconiosis with DIF, although it was not significantly different compared with that in dysplasias from pneumoconiosis without DIF (5 [50%] of 10 versus 12 [38%] of 32). Taken together, these results may suggest a positive causal relationship between pneumoconiosis and peripheral-type SCCs of the lung, and further indicate a pivotal role of diffuse fibrosis for the excess incidence of lung cancers, especially peripheral-type SCCs, in DIF-type pneumoconiosis.