Ras oncoprotein expression in erionite- and asbestos-induced Turkish malignant pleural mesothelioma patients--a pilot study

Our plain-English summary of Ras oncoprotein expression in erionite- and asbestos-induced Turkish malignant pleural mesothelioma patients--a pilot study, by A. Olut, P. Firat, D. Ertugrul, et al (Respiratory Medicine, 2001).

The study

• Authors: A. Olut, P. Firat, D. Ertugrul, Y. Gungen, S. Emri
• Journal: Respiratory Medicine
• Published: 2001;95(8):697-8
• Cited by: 7 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Summary of the article

This short report examined whether ras oncoprotein expression plays a role in malignant pleural mesothelioma caused by environmental exposure to asbestos or erionite (a fibrous zeolite) in Turkey. In some villages of rural Anatolia, this disease accounts for more than 50% of total deaths. The study included 31 patients with malignant pleural mesothelioma at Hacettepe University School of Medicine, Ankara. Diagnosis was based on histological examination of tissue obtained by percutaneous pleural biopsy, thoracoscopy or thoracotomy. Patients were grouped by the mineral to which they had been exposed, based on previously documented environmental exposure in the villages where they lived: asbestos for 16 patients and erionite for 15. The study dates were not stated. Expression of p21 ras oncoprotein was measured by immunohistochemistry on paraffin-embedded tissue sections, using a commercial antibody that detects H-, K- and N-ras products. Groups were compared with Fisher's exact test. Five of the 31 samples (16%) showed ras expression: 3 of 21 epithelial, 2 of 8 mixed-type and none of 2 fibrous mesotheliomas. Staining was only focal and cytoplasmic, and its intensity ranged from mild to moderate. Expression was found in 4 of 15 erionite-induced cases (27%) and 1 of 16 asbestos-induced cases (6%). This difference was not statistically significant. The authors concluded that ras oncoprotein expression does not seem to be significantly involved in the development of environmentally induced mesothelioma in Turkey. They described the expression in more than a quarter of erionite-induced cases as a new finding and recommended further investigation using molecular techniques.

PubMed has no abstract for this study, and the article doesn't print one. We wrote this summary from the full article with the help of AI. It is not the authors' wording.

In plain English

This short report described a pilot study from Hacettepe University in Ankara, Turkey. It looked at whether a cancer-related protein called p21 ras appeared in tumour tissue from 31 Turkish patients with malignant pleural mesothelioma. The authors grouped patients by the mineral they had been exposed to in their villages: asbestos for 16 patients and erionite, a fibrous zeolite mineral, for 15. The asbestos fiber type was not named. Exposure was based on earlier records of minerals in the patients' villages. Tissue samples were stained with an antibody that detects the H-, K- and N-ras proteins. Five of the 31 samples (16%) showed ras staining, and the staining was only focal and mild to moderate. Four of 15 erionite-related cases (27%) and one of 16 asbestos-related cases (6%) showed it. This difference was not statistically significant. The authors concluded that ras expression did not seem to be significantly involved in these environmentally caused mesotheliomas. They called the erionite finding new and said erionite's possible role in ras gene mutations should be investigated with molecular methods rather than immunohistochemistry.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Pilot study (short report) using immunohistochemical staining of tumour tissue, comparing two exposure groups with Fisher's exact test
• Who was studied: 31 Turkish patients with malignant pleural mesothelioma from villages where environmental exposure was documented, diagnosed by percutaneous pleural biopsy, thoracoscopy or thoracotomy at Hacettepe University, Ankara; study dates not given
• Exposure: Environmental exposure to asbestos (fiber type not specified; 16 patients) or erionite, a fibrous zeolite (15 patients), assigned from earlier documentation of the minerals present in each patient's village
• Main results:
  • 5 of 31 samples (16%) showed ras expression: 3 of 21 epithelial, 2 of 8 mixed type, and none of the 2 fibrous mesotheliomas
  • Staining in positive cases was only focal and cytoplasmic, with mild to moderate intensity
  • 4 of 15 erionite-related mesotheliomas (27%) and 1 of 16 asbestos-related mesotheliomas (6%) showed p21 expression
  • The difference between the erionite and asbestos groups was reported as not statistically significant
• The authors' conclusion: The authors concluded that ras oncoprotein expression did not seem to be significantly involved in the development of environmentally caused malignant pleural mesothelioma in Turkey. They described the finding that more than one quarter of erionite-related cases showed ras oncoprotein expression as new. They said the contribution of erionite to ras oncogene mutations should be investigated by more specific techniques, such as molecular analysis.
• Limitations the authors state:
  • The authors indicated that immunohistochemistry, the method used here, is less specific than molecular analysis for investigating erionite's contribution to ras oncogene mutations

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma.

Medical terms in this study, explained in our Lexicon: erionite, Pleural Mesothelioma, Environmental Exposure, Zeolite, Pleural Biopsy, Thoracoscopy, Thoracotomy, Immunohistochemistry.

Related studies

• Prognostic significance of Bax and Fas ligand in erionite and asbestos induced Turkish malignant pleural mesothelioma — N. Kokturk, P. Firat, et al. (2005)
• Erionite exposure in North Dakota and Turkish villages with mesothelioma — M. Carbone, Y.I. Baris, et al. (2011)
• Lung diseases due to environmental exposures to erionite and asbestos in Turkey — S. Emri, A. Demir, et al. (2002)
• Erionite bodies and fibres in bronchoalveolar lavage fluid (BALF) of residents from Tuzköy, Cappadocia, Turkey — P. Dumortier, L. Coplü, et al. (2001)
• The role of environmental and occupational exposures in Turkish immigrants with fibre-related disease — P. Dumortier, A. Göcmen, et al. (2001)
• Patterns of c-fos and c-jun proto-oncogene expression, apoptosis, and proliferation in rat pleural mesothelial cells exposed to erionite or asbestos fibers — C.R. Timblin, G.D. Guthrie, et al. (1998)

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