The Effect on Cognition of Mitochondrial Respiratory System Proteins in Peripheral Blood Mononuclear Cells in the Course of Lung Cancer

Factors associated with cancer-related cognitive impairment in patients with lung cancer: A systematic review

PURPOSE

Cognitive impairment is common in lung cancer patients and impacts their quality of life. Little is known about the etiology of cognitive impairment in lung cancer patients. However, the associated factors of cognitive impairment among lung cancer patients have not been systematically reviewed. This review aimed to summarize the factors related to cognitive impairment among lung cancer patients.

METHODS

PubMed, EMBASE, PsycINFO, CINAHL Plus, and Web of Science were searched to retrieve articles published from data inception until January 21, 2024, focusing on factors associated with cognitive impairment among lung cancer patients. Critical appraisal was undertaken by two reviewers independently using the Newcastle-Ottawa Scale.

RESULTS

A total of 17 observational studies were included. The results showed that 20 factors are associated with cognitive impairment, including psychological factors (loneliness, fatigue, anxiety, depression, high symptom burden, and baseline cognitive impairment), lifestyle and functional factors (daily step counts, smoking, and activities of daily living or instrumental activities of daily living impairments), medical treatment factors (cranial irradiation, chemotherapy, lobar resection, postoperative delirium, and on medication), and neuroimmunological factors (have neuronal autoantibodies, altered Default Mode Network connectivity, dysregulation in glutamate and glutamate metabolism, mitochondrial dysfunction, blood-brain barrier leakage, and reduced T-lymphocytes).

CONCLUSION

This is the first study to systematically review 20 factors associated with cognitive impairment among lung cancer patients, encompassing psychology, lifestyle and functional, medical treatment, and neuroimmunological factors. These findings can help clinicians identify at-risk patients and develop evidence-based interventions to prevent cognitive impairment among lung cancer patients.

Quantitative analysis of the mitochondrial proteome in human ovarian carcinomas

Mitochondria play important roles in growth, signal transduction, division, tumorigenesis and energy metabolism in epithelial ovarian carcinomas (EOCs) without an effective biomarker. To investigate the proteomic profile of EOC mitochondrial proteins, a 6-plex isobaric tag for relative and absolute quantification (iTRAQ) proteomics was used to identify mitochondrial expressed proteins (mtEPs) in EOCs relative to controls, followed by an integrative analysis of the identified mtEPs and the Cancer Genome Atlas (TCGA) data from 419 patients. A total of 5115 quantified proteins were identified from purified mitochondrial samples, and 262 proteins were significantly related to overall survival in EOC patients. Furthermore, 63 proteins were identified as potential biomarkers for the development of an EOC, and our findings were consistent with previous reports on a certain extent. Pathway network analysis identified 70 signaling pathways. Interestingly, the results demonstrated that cancer cells exhibited an increased dependence on mitophagy, such as peroxisome, phagosome, lysosome, valine, leucine and isoleucine degradation and fatty acid degradation pathways, which might play an important role in EOC invasion and metastasis. Five proteins (GLDC, PCK2, IDH2, CPT2 and HMGCS2) located in the mitochondrion and enriched pathways were selected for further analysis in an EOC cell line and tissues, and the results confirmed reliability of iTRAQ proteomics. These findings provide a large-scale mitochondrial proteomic profiling with quantitative information, a certain number of potential protein biomarkers and a novel vision in the mitophagy bio-mechanism of a human ovarian carcinoma.

The Markers of Glutamate Metabolism in Peripheral Blood Mononuclear Cells and Neurological Complications in Lung Cancer Patients

Objective. To evaluate the involvement of glutamate metabolism in peripheral blood mononuclear cells (PBMC) in the development of neurological complications in lung cancer and during chemotherapy. Methods. The prospective study included 221 lung cancer patients treated with chemotherapeutics. Neurological status and cognitive functions were evaluated at baseline and after 6-month follow-up. Glutamate level, the activities of glutaminase- (GLS-) glutamate synthetizing enzyme, glutamate dehydrogenase (GDH), and glutamate decarboxylase catalyzing glutamate degradation were analyzed in PBMC and in sera of lung cancer patients by means of spectrophotometric and colorimetric methods. Results. Chemotherapy of lung neoplasms induced increase of glutamate content in PBMC and its concentration in serum increased the activity of GDH in PBMC and decreased activity of glutaminase in PBMC. The changes in glutamate metabolism markers were associated with initial manifestation of neurological deficit in lung cancer patients and with new symptoms, which appear as a complication of chemotherapy. Moreover, the analyzed parameters of glutamate control correlated with a spectrum of cognitive functions measures in lung cancer patients. Conclusion. We have demonstrated dysregulation in glutamate and glutamate metabolism controlling enzymes as promising indicators of risk for chemotherapy-induced neurological complications in lung cancer patients with particular emphasis on cognitive impairment.