The role of tumor necrosis factor (TNF)-α in the antitumor effect of intrapleural injection of Lactobacillus casei strain Shirota in mice

The involvement of several cytokines in the antitumor effect induced by intrapleural (i.pl.) injection of heat-killed cells of Lactobacillus casei strain Shirota (LC 9018) in mice was investigated. Injection of LC 9018 i.pl. into Meth A fibrosarcoma (Meth A)-bearing mice not only significantly prolonged the survival of the mice, but also effectively inhibited the accumulation of malignant pleural fluid in the thoracic cavity. In the thoracic cavity of tumor-bearing mice treated with LC 9018, we observed large amounts of several cytokines including interleukin (IL)-1β, interferon (IFN)-γ, IL-12 and tumor necrosis factor (TNF)-α. Both anti-IFN-γ and anti-IL-12 monoclonal antibody (mAb) treatments partially diminished the antitumor activity of LC 9018 in vivo, while the treatment of anti-IL-1β mAb did not influence the survival of the mice. However, anti-TNF-α mAb treatment completely abolished the antitumor effect of LC 9018 in vivo, suggesting that in this model LC 9018 has a survival-prolonging effect involving certain cytokines. Moreover, i.pl. injection of mouse recombinant TNF-α into Meth A-bearing mice pretreated with anti-TNF-α mAb partially restored the survival-enhancing effect of LC 9018. These results led us to conclude that TNF-α induced by i.pl. injection of LC 9018 plays an important role in the antitumor effect of LC 9018 in vivo. Received: 22 February 1999     

Translocation chromosome 7 of A431 cells contains amplification and rearrangement of EGF receptor gene responsible for production of variant mRNA

The epidermal growth factor (EGF) receptor, along with several oncogene protein products, possesses tyrosine-specific protein kinase activity. Furthermore, the EGF receptor has structural similarity to the putitive v-erb-B transforming protein. Because of these closely shared characteristics, it is important to elucidate the possible involvement of the EGF receptor in malignant transformation. The epidermal carcinoma cell line A431 exhibits an abnormally high number of EGF receptors, which is associated with the presence of translocation chromosome M4. Recently, A431 cells have been shown to contain amplified sequences for the EGF receptor gene(s) and also to produce a variant mRNA which diverges from the normal EGF receptor mRNA at the 3 end. Here we report, using the human EGF receptor cDNA probe pE7, that the chromosome M4 has a six-to sevenfold amplification of the EGF receptor gene. Furthermore, the presence of M4 in somatic cell hybrids correlates with the production of the variant 2.9-kb mRNA. This aberrant mRNA is apparently generated by an intrachromosomal rearrangement which was detected using as a probe a fragment of the pE15cDNA encoding the variant mRNA.     

Axillary management based on American college of surgeons oncology group Z0011 criteria makes it possible to omit intraoperative diagnosis of sentinel lymph nodes in early breast cancer patients

The ACOSOG Z0011 trial has resulted in the omission of axillary lymph node dissection (ALND) in early breast cancer patients with one or two metastatic sentinel lymph nodes (SLNs). There has been increasing interest in the necessity of intraoperative assessment of SLNs in patients treated based on the Z0011 criteria. We evaluated the utility of intraoperative assessment in these eligible patients. A total of 1396 patients were treated following the Z0011 criteria from April 2012 to December 2019. We examined the proportion and clinicopathological features of patients who underwent ALND due to three or more metastatic SLNs and the sensitivity of intraoperative assessment. Only 16 (1.1%) patients had three or more metastatic SLNs diagnosed by intraoperative assessment, and they immediately underwent ALND. Of the clinicopathological factors, high clinical tumor stage (p = 0.002) and high Ki-67 labeling index value (p = 0.056) were more likely to be associated with the presence of three or more metastatic SLNs. The major independent risk factor for three or more metastatic SLNs was high clinical tumor stage (OR 3.94 [95% CI 1.42–11.0]; p = 0.009). Intraoperative assessment had low sensitivity (70.5%) and a high false-negative rate (29.5%) in detecting SLN metastases. The main finding of our study was the small proportion of patients who required ALND due to three or more metastatic SLNs according to the Z0011 criteria. The Z0011 strategy enables intraoperative assessment of SLNs to be omitted in early breast cancer patients.     

Previous exposure to VTA amphetamine enhances cocaine self-administration under a progressive ratio schedule in an NMDA, AMPA/kainate, and metabotropic glutamate receptor-dependent manner.

Previous exposure to amphetamine (AMPH) in the ventral tegmental area (VTA) enhances cocaine self-administration in a D(1) dopamine receptor-dependent manner. The present study examined the contribution of VTA NMDA, AMPA/kainate, and metabotropic glutamate (mGlu) receptors to this effect. Rats in different groups received three intra-VTA injections, one every third day, of either saline (0.5 microl/side), AMPH (2.5 microg/0.5 microl/side), AMPH+CPP (NMDA receptor antagonist; 10 microM or 100 microM/0.5 microl/side), AMPH+CNQX (AMPA/kainate receptor antagonist; 0.3 mM or 1 mM/0.5 microl/side), AMPH+MCPG (mGlu receptor antagonist; 0.5 mM or 50 mM/0.5 microl/side), or the glutamate receptor antagonists alone. Starting 7-10 days after the last pre-exposure injection, rats were trained to self-administer cocaine (0.3 mg/kg/infusion) and then tested under a progressive ratio (PR) schedule of reinforcement for 6 consecutive days. As reported previously, VTA AMPH pre-exposed rats worked more and obtained more infusions of cocaine than saline pre-exposed animals. Coadministration of CPP, CNQX, or MCPG with AMPH during pre-exposure dose-dependently blocked this enhancement of cocaine self-administration. Rats pre-exposed to the glutamate receptor antagonists alone did not differ on the test days from the saline pre-exposed controls. These results indicate that, in a manner paralleling the induction of sensitization of the locomotor stimulating effects of AMPH, activation of NMDA, AMPA/kainate, and mGlu receptors during pre-exposure to AMPH in the VTA is necessary for the enhancement of cocaine self-administration to develop.     

The relationship between epidermal growth factor receptor mutations and clinicopathologic features in non-small cell lung cancers.

PURPOSE: Recent studies reported that clinical responsiveness to gefitinib was associated with somatic mutation of epidermal growth factor receptor (EGFR) gene in non-small cell lung cancers (NSCLC). Here, we investigated the relationship between EGFR mutation and clinicopathologic features. EXPERIMENTAL DESIGN: EGFR mutational status of 120 NSCLCs was determined mainly in EGFR exons 18 to 21 by direct sequence and correlated with clinicopathologic parameters. RESULTS: EGFR mutations were present in 38 cases (32%) and the majority of mutations were in-frame deletions of exon 19 (19 cases) and a missense mutation in exon 21 (18 cases). EGFR mutations were frequently associated with adenocarcinoma (P < 0.0001), never smoker (P < 0.0001), and female gender (P = 0.0001). Of interest, increasing smoke exposure was inversely related to the rate of EGFR mutation (P < 0.0001). Multivariate analysis showed that smoking and histology were independent variables. Furthermore, gender difference was observed for the mutational location (P = 0.01) dominance of exon 19 for males and exon 21 for females. Twenty-one cases were treated with gefitinib and found that EGFR mutation was significantly related to gefitinib responsiveness (P = 0.002). In addition, median survival times of patients with and without EGFR mutations treated with gefitinib were 25.1 and 14.0 months, respectively. Patients with EGFR mutations had approximately 2-fold survival advantage; however, the difference was not significant. CONCLUSIONS: We show that EGFR mutations were significantly related to histology and smoke exposure and were a strong predictive factor for gefitinib responsiveness in NSCLC.     

Evaluation of community-acquired pneumonia guidelines of Japanese Respiratory Society: differentiation of atypical pneumonia and bacterial pneumonia]

To evaluate the usefulness of differentiation of atypical pneumonia and bacterial pneumonia in the community-acquired pneumonia guidelines of the Japanese Respiratory Society, we investigated 124 cases of three atypical pneumonias (Mycoplasma pneumonia, 62 cases; Chlamydia pneumoniae pneumonia, 46 cases; Chlamydia psittaci pneumonia, 13 cases) and 403 cases of bacterial pneumonia at our hospital over seven years. Overall, the sensitivity and specificity of the criteria in the guideline were 70.4% and 91.8%, respectively. High accordance was recognized in patients under 60 years old with atypical pneumonia. Items in the criteria that included subjective factors were considered inassessable. We found that the differentiation of pneumonias in the guideline is useful for the diagnosis of atypical pneumonia among younger patients, but it should be concise and objective. We therefore propose that the criteria would be more effective if they consisted of only 4 items: age under 60 years, no underlying disorders, presence of stubborn dry cough, and normal peripheral white blood cell count.     

Genetics of cell surface receptors for bioactive polypeptides: Binding of epidermal growth factor is associated with the presence of human chromosome 7 in human-mouse cell hybrids

Mouse A9 cells, L-cell-derived mutants deficient in hypoxanthine phosphoribosyltransferase (HPRT; IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) were found to be incapable of binding ¹²⁵I-labeled epidermal growth factor (EGF) to the cell surface. The A9 cells were fused with human diploid fibroblasts (WI-38) possessing EGF-binding ability, and human-mouse cell hybrids (TA series) were isolated after hypoxanthine/aminopterin/thymidine/ouabain selection. Analyses of isozyme markers and chromosomes of four representative clones of TA hybrids indicated that the expression of EGF-binding ability is correlated with the presence of human chromosome 7 or 19. Four subclones were isolated from an EGF-binding-positive line, TA-4, and segregation of EGF-binding was found to be concordant with the expression of human mitochondrial malate dehydrogenase (MDHM; L-malate:NAD⁺ oxidoreductase, EC 1.1.1.37), a marker for chromosome 7, but not with glucosephosphate isomerase (GPI; D-glucose-6-phosphate ketol-isomerase, EC 5.3.1.9), a marker for chromosome 19. Furthermore, evidence from 27 clones of AUG hybrids that were produced between A9 and another human fibroblast line, GM1696, carrying an X/7 chromosome translocation indicated that EGF-binding ability segregates together with human MDHM and two X-linked markers, HPRT and glucose-6-phosphate dehydrogenase (G6PD; D-glucose-6-phosphate:NADP⁺ 1-oxidoreductase, EC 1.1.1.49), that are located on the translocation chromosome 7p⁺. These results permit assignment of the gene, designated EGFS, which is associated with the expression of EGF-binding ability, to human chromosome 7 and its localization to the p22-qter region. Because the EGF receptor is reported to be a glycoprotein the EGFS could be either a structural gene(s) for receptor protein or a gene(s) for modifying the receptor protein through glycosylation.