16 June 2015: Clinical Research
Molecular Analysis by Gene Expression of Mitochondrial ATPase Subunits in Papillary Thyroid Cancer: Is ATP5E Transcript a Possible Early Tumor Marker?
Luis Mauricio Hurtado-López ABCDEFG , Fernando Fernández-Ramírez BCD , Eva Martínez-Peñafiel CD , José Damián Carrillo Ruiz DEFG , Norma Estela Herrera González ABCDEFG
DOI: 10.12659/MSM.893597
Med Sci Monit 2015; 21:1745-1751
Abstract
BACKGROUND: Cancer development involves an “injury” to the respiratory machinery (Warburg effect) due to decreased or impaired mitochondrial function. This circumstance results in a down regulation of some of the ATPase subunits of the malignant tissue. The objective of this work was to assess and compare the relative expression of mRNA of mitochondrial ATPase subunits between samples of thyroid cancer and benign nodules.
MATERIAL AND METHODS: Samples from 31 patients who had an operation for PTC at the General Hospital of Mexico were snap-frozen and stored at –70°C. Thirty-five patients who had an operation for benign tumors were also included in the study. mRNA expression levels of alpha, beta, gamma, and epsilon subunits of F1 and “c12” of subunit Fo were determined by real-time RT-PCR (by duplicate), in order to determine if abnormal expression of these genes could partially explain the Warburg effect in papillary thyroid cancer (PTC).
RESULTS: ATP5E transcript alteration (down-expression) was highly associated to PTC diagnosis OR=11.76 (95% confidence interval, 1.245–237.98; p=0.04).
CONCLUSIONS: Relative down-expression of ATP5E transcript was highly associated with PTC diagnosis. This transcript alteration may be used as a tumoral marker in papillary thyroid cancer.
Keywords: Biomarkers, Tumor - genetics, Adolescent, Carcinoma - pathology, Mitochondrial Proton-Translocating ATPases - genetics, Prospective Studies, Proteins - metabolism, RNA, Messenger - metabolism, Thyroid Neoplasms - pathology, young adult
Background
The most commonly used tool for diagnosis of non-functional thyroid nodules is fine-needle aspiration biopsy (FNAB) [1–3]. However, FNAB still do not provide a diagnosis in 30–40% of cases [4–11]; consequently, non-diagnosed patients must be subjected to diagnostic surgery, which could impact in recurrent laryngeal nerve and parathyroid gland [12–14]morbidity.
Many groups have used diverse alternate diagnostic methods in attempting to define this situation. These methods include ultrasound [15–18], ultrasonographic elastography [19–21], repeated FNAB [22], determination of mutations of BRAFv600e and rearrangements of RET/PTC [23–27], and assessing genetic panels [28,29]. Despite these efforts, when it is decided not to operate on a patient based on these alternate diagnostic tools, the risk exists of not diagnosing a cancer and leaving it to evolve freely in at least 25–30% of the cases.
In an attempt to resolve this problem, metabolic assessment of the thyroid nodule by gammagraphy with technetium-99m (Tc-99m) and Tc-99m-methoxyisobutylisonitrile (MIBI) was proposed. It was found that all thyroid cancer lesions accumulate MIBI (understood as accumulation of the net result of uptake and outflow of the radio-molecule), obtaining a 100% sensitivity and a negative predictive value of 100% [30]. This negative predictive value has been of great clinical use in ruling-out cancer. This characteristic has been found since use of the first
The same diagnostic value (negative predictive value of 97–100% [42–46]) can be achieved in thyroid nodules assessed through non-diagnostic aspiration biopsy by means of 18F-fluorodeoxyglucose positron emission tomography (PET).
MIBI is not retained in benign cells; it enters into the mitochondrial matrix because it is a lipophilic cation and there is a natural negative charge in the mitochondrial matrix, but the moment at which oxidative phosphorylation occurs, MIBI is washed out of the mitochondrial matrix [47–49]. In cancer cells, oxidative phosphorylation and ATP production are altered, since conversion of ADP to ATP by ATPases is inhibited. In contrast, pumping of hydrogen ions (protons) from the mitochondrial matrix to the intermembrane space continues due to the function of the respiratory chain, which intensifies the negative polarity in the mitochondrial matrix (Warburg effect); in consequence, MIBI retention in the mitochondrial matrix is higher and persistent [50–53]. It has been demonstrated that the electrical gradient difference of the mitochondrial transmembrane potential (δΨm) increases from −60 mV (normal in the mitochondrial matrix) to between −150 and −170 mV [54–59] in cancerous tissue.
This Warburg effect is the reason why PET also has the above-mentioned diagnostic value, because by not producing ATP the cell must consume a large amount of glucose [60–63].
Accordingly, this situation could be related to differences in mitochondrial ATPases between normal and neoplastic cells. The mitochondrial ATPase is characterized as having 2 main multiprotein components: F0, immersed in the internal mitochondrial membrane and consisting of 3 types of proteins (subunits) called a1, b2 and c12; and F1, which is oriented towards the mitochondrial matrix and has 5 different polypeptides (subunits) called alpha3, beta3, delta, gamma, and epsilon [65].
Under normal conditions, the flow of protons produced by oxidative phosphorylation is pumped from the mitochondrial matrix to the mitochondrial intermembrane space. Subsequently, these protons return to the mitochondrial matrix by means of the proton channel located in subunit a1 of component F0, inducing rotation of subunit c12 of F0 and this in turn induces rotation of subunits gamma and epsilon of component F1. This rotation produces changes in the binding affinity of ATPase induced by ADP and Pi, which finally leads to production of 3 ATP molecules for each 360º rotation of subunit gamma. In cancer cells this ATP is not produced at the same level (Warburg effect). It is still not known whether any subunit of F0 or F1 presents a structural dysfunction. However, some authors have attributed this dysfunction to component F1; protein beta has specifically been involved in liver cancer [65–78].
Based on the above, we studied the difference in the relative expression of mRNA of the ATPase subunits between paired malignant lesions and healthy tissues from papillary thyroid cancer patients. Benign tumors of the thyroid gland were analyzed as well. We measured alpha, beta, gamma, and epsilon of subunit F1 and that of the “c12” of subunit F0.
The objective of this work was to assess the difference in the relative mRNA expression of the thyroid mitochondrial ATPase subunits between benign and malignant lesions.
Material and Methods
PATIENTS:
Thirty-one PTC patients were included in this study, with an average age of 43.7 years (range 18–78); 29 were women (93.5%), having an average age of 44.2 years.
Thirty-five patients with colloid goiter were studied, with an average age of 45 years (range 20–87); 32 were women (91.4%), with an average age of 44.5 years. Both groups were homogenous in terms of age and sex.
Results
ATP5A1:
Eleven patients showed down-regulation of this transcript in PTC. In this group, just 1 patient had equal to or less than Z=−1.96. Twenty patients showed up-regulation in PTC; in this group, only 1 had equal to or more than Z=+1.96. The colloid goiter group had 12 patients with down-regulated transcript level, of which none had equal to or less than Z=−1.96 and 23 had up-regulation, of which none had equal to or more than Z=+1.96. In comparing down-regulation (equal or less than Z=−1.96), the 1-sided Fisher’s exact test result was p=0.478.
ATP5B:
In the papillary cancer group, 7 patients had down-regulated transcript level, of which none had equal to or less than Z=−1.96. Twenty-four patients had up-regulation, of which none had equal to or more than Z=+1.96. In the colloid goiter group, 3 patients had down-regulated transcript level, of which none had equal to or less than Z=−1.96 and 32 patients had up-regulation, of which none had equal to or more than Z=+1.96. In comparing down-regulation (equal or less than Z=−1.96), the 1-sided Fisher’s exact test score was p=0.277.
ATP5C1:
The papillary cancer group had 12 patients with down-regulated transcript level, of which none had equal or less than Z=−1.96 and 19 had up-regulation, of which no patients had equal to or more than Z=+1.96. The colloid goiter group had 12 patients with down-regulated transcript level. In this group no patients had equal to or less than Z=−1.96; 23 had up-regulation, of which no patients had equal to or more than Z=+1.96. In comparing down-regulation (equal to or less than Z=−1.96), the 1-sided Fisher’s exact test score was p=1.
ATP5E:
Sixteen patients with PTC showed down-regulation of this transcript, of which 6 patients had equal to or less than Z=−1.96 and 15 showed up-regulation, of which none had equal to or more than Z=+1.96. The colloid goiter group had 9 patients with down-regulation of the transcript, of which none had equal to or less than Z=−1.96; 26 patients had up-regulation, of which none had equal to or more than Z=+1.96. The OR was 11.76 (95% confidence interval, 1.245–237.98) in comparing down-regulation (equal or less than Z=−1.96) and the 1-sided Fisher’s exact test score was p=0.045 (Figure 1).
ATP5G1:
In the papillary cancer group 21 patients had down-regulated transcript level, of which 5 patients had equal to or less than Z=−1.96 and 8 had up-regulation, of which none had equal to or more than Z=+1.96. The colloid goiter group had 23 patients with down-regulated transcript level, of which 2 patients had equal to or less than Z=−1.96 and 12 up regulation, of which none had equal to or more than Z=+1.96. OR=3.28 (95% confidence interval, 0.56–19.15). In comparing down-regulation (equal or less than Z=−1.96), the 1-sided Fisher’s exact test score was p= 0.17.
ATP5G2:
In the papillary cancer group 16 patients had down-regulated transcript level, of which only 1 patient had equal to or less than Z=−1.96 and 15 had up-regulation, of which none had equal to or more than Z=+1.96. The colloid goiter group had 15 patients with down-regulated transcript level, of which none had equal to or less than Z=−1.96 and 20 had up-regulation, of which none had equal to or more than Z=+1.96. The OR was 3.0 (95% confidence interval, 0.11–79.49). In comparing down-regulation (equal or less than Z=−1.96), the 1-sided Fisher’s exact test score was p=0.51.
ATP5G3:
In the papillary cancer group 13 patients had down-regulated transcript level, of which 4 had equal to or less than Z=−1.96, and 18 patients had up-regulation, of which none had equal to or more than Z=+1.96. In the colloid goiter group 21 patients had down-regulated transcript level, of which 4 had equal to or less than Z=−1.96 and 14 patients had up-regulation, of which none had equal to or more than Z=+1.96. The OR was 1.88 (95% confidence interval, 0.37–9.39). In comparing down-regulation (equal or less than Z=−1.96), the 1-sided Fisher’s exact test result was p=0.35.
According to several distance-based clustering algorithms (Figure 2), at the level of genes (Y axis), the behavior of ATP5G1 and ATP5G2 was similar since they are located in the same branch. The order of similarity was ATP5E, ATP5C1, and finally ATP5G2, all of which belong to 1 major cluster. The other cluster includes ATP5A1 and ATP5B, which segregate in a separate branch. This may represent biological coherence, as each major branch corresponds to F0 and F1 complexes, respectively.
Discussion
It is well established that during cancer progression, alteration of the mitochondrial respiratory chain occurs. Some of the changes that the mitochondria may exhibit during the development and progression of most cancer cells are the differential expression of respiratory chain subunits and of glycolytic enzymes. It is important to remember that elevated glycolysis in cancer cells does not necessarily mean that these cells only use the glycolytic pathway for ATP generation. However, this peculiar aerobic metabolism of cancer cells, now called the “seven hallmarks” of the cancer phenotype, may in the future help in the diagnosis, prognosis, and treatment of the disease [82].
Under aerobic conditions, normal cells utilize glucose, which is converted to pyruvate and then to CO2, and water through the Tricarboxylic acid cycle (TCA) and oxidative phosphorylation in mitochondria. Oxygen acts as an electron acceptor, allowing the recycling of NADH to NAD+. When the cells have a limited supply of oxygen or have an impairment that impedes oxidation of pyruvate, this molecule then is reduced to lactate in the cytoplasm. This is an inefficient process producing 2 moles of ATP for every mole of glucose consumed. Cancer cells convert most of their glucose into lactate (regardless of presence of oxygen), aiding their own natural selection [83]. In accordance with these findings, it has been shown that most cancer cells have mutations in the TCA cycle enzymes, such as succinate dehydrogenase and fumarate hydratase, leading to metabolic changes that have already been observed at the RNA level [84,85]. Transcriptome changes in carcinogenesis have been widely studied and a great amount of data has been published [86–89]. However, most of these data require confirmation by means of a highly accurate method of quantitative real-time PCR.
Finding a considerable differential gene expression of mitochondrial F0 and F1 ATPase subunits between papillary thyroid cancer and a benign condition would be of great help because the diagnosis of malignancy in the thyroid nodule has not yet been resolved. Genes encoding alpha, beta, gamma, and epsilon of F1, and “c12” of subunit F0, were analyzed at the RNA level (q PCR by duplicate) to determine if abnormal expression of these genes could partially explain the Warburg effect occurring in PTC.
We propose that transcriptional analysis of several ATPase genes expressed by thyroid tumors should provide a means to define a signature fingerprint of molecular mechanisms underlying this type of cancer and might progressively improve conventional diagnosis parameters. Simultaneous expression levels of several genes offer better possibilities to understand and characterize the molecular mechanisms underlying PTC. Other studies have found correlations among mRNA expression and clinical characteristics of the disease. For example, in breast cancer Sorlie found certain expression patterns of mRNA related to tumor subclasses with clinical implications [90].
Few alterations have been reported to be associated with PTC at the molecular level. To the best of our knowledge, assessment of mitochondrial RNA expression of the ATPase subunits from thyroid tissue has not been analyzed by qPCR.
It is very clear from the results of the present study that there is a high degree of individual variability of the ATPase subunits expression for each patient (regardless of the type of illness), showing a unique profile of mRNA expression for each of the 6 genes measured.
From all 6 genes included in the present study, ATP5E transcript down-expression was highly associated only with PTC diagnosis OR=11.76 (95% CI 1.245–237.98, p=0.04). Many PTC patients displayed deregulation of this transcript. We recognize the limitation of having a very wide confidence interval, which means that we must confirm this initial information with a larger sample. This deregulation in PTC may explain why the rotation of gamma and epsilon F1 subunits stops, thus, avoiding changes in the binding affinity of the catalytic subunits for ADP and Pi, and finally altering the ATP production [91,92].
Conclusions
ATP5E down-regulation transcript expression was highly associated only with PTC diagnosis and not with colloid goiter.
References
1. Cooper DS, Doherty GM, Haugen BR, Management guidelines for patients with thyroid nodules and differentiated thyroid cancer: Thyroid, 2006; 16; 109-42, pmid: 16420177
2. , American Association of Clinical Endocrinologists and Associazione Medici Endocrinologi Medical Guidelines for Clinical Practice for the Diagnosis and Management of Thyroid Nodules Endocrine Practice, 2006; 12; 63-102
3. Hegedus L, Clinical practice. The thyroid nodule: N Engl J Med, 2004; 351; 1764-71, pmid: 15496625
4. Layfield LJ, Cibas ES, Gharib H, Mandel SJ, Thyroid Aspiration Cytology: Current Status: Cancer J Clin, 2009; 59; 99-110
5. Peng Y, Wang HH, A meta-analysis of comparing fine-needle aspiration and frozen section for evaluating thyroid nodules: Diagn Cytopathol, 2008; 36; 916-20, pmid: 18855886
6. Basolo F, Ugolini C, Proietti A, Role of frozen section associated with intraoperative cytology in comparison to FNA and FS alone in the management of thyroid nodules: Eur J Surg Oncol, 2007; 6; 769-75, pmid: 17223305
7. Wang HH, Reporting thyroid fine-needle aspiration: literature review and a proposal: Diagn Cytopathol, 2006; 34; 67-76, pmid: 16355378
8. Carmeci C, Jeffrey RB, McDougall IR, Ultrasound-guided fine-needle aspiration biopsy of thyroid masses: Thyroid, 1998; 8; 283-89, pmid: 9588492
9. Mazzaferri ELN, Management of a solitary thyroid nodule: N Engl J Med, 1993; 328; 553-59, pmid: 8426623
10. Gharib H, Goellner JR, Fine-needle aspiration biopsy of the thyroid: an appraisal: Ann Intern Med, 1993; 118; 282-89, pmid: 8420446
11. Alexander EK, Hurwitz S, Heering JP, Natural history of benign solid and cystic thyroid nodules: Ann Intern Med, 2003; 138; 315-18, pmid: 12585829
12. Chiang FY, Wang LF, Huang YF, Recurrent laryngeal nerve palsy after thyroidectomy with routine identification of the recurrent laryngeal nerve: Surgery, 2005; 137; 342-47, pmid: 15746790
13. Sevim T, Risk factors for permanent laryngeal nerve paralysis in patients with thyroid carcinoma: Clin Otolaryngol, 2007; 32(5); 378-83, pmid: 17883559
14. Glinoer D, Andry G, Chantrain G, Samil N, Clinical aspects of early and late hypocalcaemia after thyroid surgery: Eur J Surg Oncol, 2000; 26; 571-77, pmid: 11034808
15. Ito Y, Amino N, Yokozawa T, Ultrasonographic evaluation of thyroid nodules in 900 patients: comparison among ultrasonographic, cytological, and histological findings: Thyroid, 2007; 17; 1269-76, pmid: 17988196
16. Zhang B, Jiang YX, Liu JB, Utility of contrast-enhanced ultrasound for evaluation of thyroid nodules: Thyroid, 2010; 20; 51-57, pmid: 20067379
17. Kwak JY, Koo H, Youk JH, Value of US correlation of a thyroid nodule with initially benign cytologic results: Radiology, 2010; 254; 292-300, pmid: 20019136
18. Sipos JA, Advances in ultrasound for the diagnosis and management of thyroid cancer: Thyroid, 2009; 19; 1363-72, pmid: 20001718
19. Asteria C, Giovanardi A, Pizzocaro A, US-Elastography in the differential diagnosis of benign and malignant thyroid nodules: Thyroid, 2008; 18; 523-31, pmid: 18466077
20. Park SH, Kim SJ, Kim EK, Interobserver agreement in assessing the sonographic and elastographic features of malignant thyroid nodules: Am J Roentgenol, 2009; 193; W416-23, pmid: 19843721
21. Hong Y, Liu X, Li Z, Real-time ultrasound elastography in the differential diagnosis of benign and malignant thyroid nodules: J Ultrasound Med, 2009; 28; 861-67, pmid: 19546328
22. Oertel YC, Miyahara-Felipe Leika, Mayo G, Value of repeated fine needle aspirations of the thyroid: an analysis of over ten thousand FNAs: Thyroid, 2007; 17; 1061-66, pmid: 17910525
23. Pizzolanti G, Russo L, Richiusa P, Fine-needle aspiration molecular analysis for the diagnosis of papillary thyroid carcinoma through BRAFV600E mutation and RET/PTC rearrangement: Thyroid, 2007; 17; 1109-15, pmid: 17727338
24. Ball DW, Selectively targeting mutant BRAF in thyroid cancer: J Clin Endocrinol Metab, 2010; 95; 60-61, pmid: 20056810
25. Xing M, BRAF mutation in papillary thyroid cancer: pathogenic role, molecular bases, and clinical implications: Endocr Rev, 2007; 28; 742-62, pmid: 17940185
26. Greco A, Borrello MG, Miranda C, Molecular pathology of differentiated thyroid cancer: Q J Nucl Med Mol Imaging, 2009; 53; 440-53, pmid: 19910897
27. Pilli T, Prasad KV, Jayarama S, Potential utility and limitations of thyroid cancer cell lines as models for studying thyroid cancer: Thyroid, 2009; 19; 1333-42, pmid: 20001716
28. Nikiforov YE, Ohori NP, Hodak SP, Impact of mutational testing on the diagnosis and management of patients with cytologically indeterminate thyroid nodules: a prospective analysis of 1056 FNA samples: J Clin Endocrinol Metab, 2011; 96; 3390-97, pmid: 21880806
29. Alexander EK, Kennedy GC, Baloch ZW, Preoperative diagnosis of benign thyroid nodules with indeterminate cytology: N Engl J Med, 2012; 367; 705-15, pmid: 22731672
30. Hurtado LLM, Arellano-Montano S, Torres-Acosta EM, Combined use of fine-needle aspiration biopsy, MIBI scans and frozen section biopsy offers the best diagnostic accuracy in the assessment of the hypofunctioning solitary thyroid nodule: Eur J Nucl Med Mol Imaging, 2004; 31; 1273-79, pmid: 15133637
31. Hassan IM, Sahweil A, Constantinides C, Uptake and kinetics of Tc-99m hexakis 2-methoxy isobutyl isonitrile in benign and malignant lesions in the lungs: Clin Nucl Med, 1989; 14; 333-40, pmid: 2721076
32. Hurtado-Lopez LM, Martinez Duncker C, Negative MIBI thyroid scans exclude differentiated and medullary thyroid cancer in 100% of patients with hypofunctioning thyroid nodules: Eur J Nucl Med Mol Imaging, 2007; 34; 1701-3, pmid: 17581750
33. Kresnik E, Gallowitsch HJ, Mikosch P, Technetium-99m-MIBI scintigraphy of thyroid nodules in an endemic goiter area: J Nucl Med, 1997; 38; 62-65, pmid: 8998152
34. Erdil TY, Ozker K, Kabasakal L, Correlation of technetium-99m MIBI and thallium-201 retention in solitary cold thyroid nodules with postoperative histopathology: Eur J Nucl Med, 2000; 27; 713-20, pmid: 10901459
35. Sarikaya A, Huseyinova G, Irfanoglu ME, The relationship between 99Tcm-sestamibi uptake and ultrastructural cell types of thyroid tumours: Nucl Med Commun, 2001; 22; 39-44, pmid: 11233550
36. Riazi A, Kalantarhormozi M, Nabipour I, Technetium-99m methoxyisobutylisonitrile scintigraphy in the assessment of cold thyroid nodules: is it time to change the approach to the management of cold thyroid nodules?: Nucl Med Commun, 2014; 35; 51-57, pmid: 24128898
37. Demirel K, Kapucu O, Yucel C, A comparison of radionuclide thyroid angiography, 99mTc-MIBI scintigraphy and power Doppler ultrasonography in the differential diagnosis of solitary cold thyroid nodules: Eur J Nucl Med Mol Imaging, 2003; 30; 642-50, pmid: 12612810
38. Foldes I, Levay A, Stotz G, Comparative scanning of thyroid nodules with technetium-99m pertechnetate and technetium-99m methoxyisobutylisonitrile: Eur J Nucl Med, 1993; 20; 330-33, pmid: 8387921
39. Alonso O, Mut F, Lago G, 99Tcm-MIBI scanning of the thyroid gland in patients with markedly decreased pertechnetate uptake: Nucl Med Commun, 1998; 19; 257-61, pmid: 9625501
40. Saggiorato E, Angusti T, Rosas R, 99mTc-MIBI imaging in the presurgical characterization of thyroid follicular neoplasms: relationship to multidrug resistance protein expression: J Nucl Med, 2009; 50; 1785-93, pmid: 19837765
41. Giovanella L, Suriano S, Maffioli M, (99m)Tc-sestamibi scanning in thyroid nodules with nondiagnostic cytology: Head Neck, 2010; 32; 607-11, pmid: 19693945
42. Mitchell JC, Grant F, Evenson AR, Preoperative evaluation of thyroid nodules with 18FDG-PET/CT: Surgery, 2005; 138; 1166-74, pmid: 16360405
43. Sebastianes FM, Cerci JJ, Zanoni PH, Role of 18F-fluorodeoxyglucose positron emission tomography in preoperative assessment of cytologically indeterminate thyroid nodules: J Clin Endocrinol Metab, 2007; 92; 4485-88, pmid: 17684046
44. Traugott AL, Dehdashti F, Trinkaus K, Exclusion of malignancy in thyroid nodules with indeterminate fine-needle aspiration cytology after negative 18F-fluorodeoxyglucose positron emission tomography: interim analysis: World J Surg, 2010; 34; 1247-53, pmid: 20140435
45. Giovanella L, Suriano S, Maffioli M, Ceriani L, 18FDG-positron emission tomography/computed tomography (PET/CT) scanning in thyroid nodules with nondiagnostic cytology: Clin Endocrinol (Oxf), 2011; 74; 644-48, pmid: 21470288
46. Pak K, Kim SJ, Kim IJ, The role of 18F-fluorodeoxyglucose positron emission tomography in differentiated thyroid cancer before surgery: Endocr Relat Cancer, 2013; 20; R203-13, pmid: 23722225
47. Chiu ML, Kronauge JF, Piwnica-Worms D, Effect of mitochondrial and plasma membrane potentials on accumulation of hexakis(2-methoxyisobutylisonitrile) technetium(I) in cultured mouse fibroblasts: J Nucl Med, 1990; 31; 1646-53, pmid: 2213187
48. Vergote J, Moretti JL, de Vries EG, Garnier-Suillerot A, Comparison of the kinetics of active efflux of 99mTc-MIBI in cells with P-glycoprotein-mediated and multidrug-resistance protein-associated multidrug-resistance phenotypes: Eur J Biochem, 1998; 252; 140-46, pmid: 9523723
49. Caldarella C, Treglia G, Pontecorvi A, Giordano A, Diagnostic performance of planar scintigraphy using 99mTc-MIBI in patients with secondary hyperparathyroidism: a meta-analysis: Ann Nucl Med, 2012; 26; 794-803, pmid: 22875577
50. Warburg O, On the origin of cancer cells: Science, 1956; 123; 309-14, pmid: 13298683
51. Chen Z, Lu W, Garcia-Prieto C, Huang P, The Warburg effect and its cancer therapeutic implications: J Bioenerg Biomembr, 2007; 39; 267-74, pmid: 17551814
52. López-Lázaro M, The warburg effect: why and how do cancer cells activate glycolysis in the presence of oxygen?: Anticancer Agents Med Chem, 2008; 8; 305-12, pmid: 18393789
53. Moretti JL, Hauet N, Caglar M, To use MIBI or not to use MIBI? That is the question when assessing tumour cells: Eur J Nucl Med Mol Imaging, 2005; 32; 836-42, pmid: 15902437
54. Chen LB, Mitochondrial membrane potential in living cells: Annu Rev Cell Biol, 1988; 4; 155-81, pmid: 3058159
55. Modica-Napolitano JS, Aprille JR, Delocalized lipophilic cations selectively target the mitochondria of carcinoma cells: Adv Drug Deliv Rev, 2001; 49; 63-70, pmid: 11377803
56. Chiu ML, Kronauge JF, Piwnica-Worms D, Effect of mitochondrial and plasma membrane potentials on accumulation of hexakis (2-methoxyisobutylisonitrile) technetium(I) in cultured mouse fibroblasts: J Nucl Med, 1990; 31; 1646-53, pmid: 2213187
57. Piwnica-Worms D, Kronauge JF, Chiu ML, Uptake and retention of hexakis (2-methoxyisobutyl isonitrile) technetium (I) in cultured chick myocardial cells: Circulation, 1990; 82; 1826-38, pmid: 2225379
58. Hockings PD, Rogers PJ, The measurement of transmembrane electrical potential with lipophilic cations: Biochim Biophys Acta, 1996; 1282; 101-6, pmid: 8679645
59. Pedersen PL, Transport ATPases into the year 2008: a brief overview related to types, structures, functions and roles in health and disease: J Bioenerg Biomembr, 2007; 39; 349-55, pmid: 18175209
60. Nijsten MW, van Dam GM, Hypothesis: using the Warburg effect against cancer by reducing glucose and providing lactate: Med Hypotheses, 2009; 73; 48-51, pmid: 19264418
61. Upadhyay M, Samal J, Kandpal M, The Warburg effect: insights from the past decade: Pharmacol Ther, 2013; 37; 318-30, pmid: 23159371
62. Bensinger SJ, Christofk HR, New aspects of the Warburg effect in cancer cell biology: Semin Cell Dev Biol, 2012; 23; 352-61, pmid: 22406683
63. Menendez JA, Joven J, Cufí S, The Warburg effect version 2.0: metabolic reprogramming of cancer stem cells: Cell Cycle, 2013; 12; 1166-79, pmid: 23549172
64. Lodish H, Berk A, Matsudaira P, Cellular energetic Chapter 8: Molecular Cell Biology, 2004; 301-50, New York, WH Freeman and Company
65. Zhou Y, Duncan TM, Cross RL: Proc Natl Acad Sci USA, 1997; 94; 10583-87, pmid: 9380678
66. Fillingame RH: J Exp Biol, 1997; 200; 217-24, pmid: 9050229
67. Xu R, Pelicano H, Zhou Y, JS , Inhibition of glycolysis in cancer cells: a novel strategy to overcome drug resistance associated with mitochondrial respiratory defect and hypoxia: Cancer Res, 2005; 65; 613-21, pmid: 15695406
68. Mayevsky A, Mitochondrial function and energy metabolism in cancer cells: past overview and future perspectives: Mitochondrion, 2009; 9; 165-79, pmid: 19460294
69. Pelicano H, Martin DS, Xu RH, Huang P, Glycolysis inhibition for anticancer treatment: Oncogene, 2006; 25; 4633-46, pmid: 16892078
70. Boyer PD, A perspective of the binding change mechanism for ATP synthesis: FASEB J, 1989; 3; 2164-78, pmid: 2526771
71. Boyer PD, A research journey with ATP synthase: J Biol Chem, 2002; 277; 39045-61, pmid: 12181328
72. Willers IM, Isidoro A, Ortega AD, Selective inhibition of beta-F1-ATPase mRNA translation in human tumours: Biochem J, 2010; 426; 319-26, pmid: 20028336
73. Cuezva JM, Ortega AD, Willers I, The tumor suppressor function of mitochondria: translation into the clinics: Biochim Biophys Acta, 2009; 1792; 1145-58, pmid: 19419707
74. Wittig I, Schägger H, Supramolecular organization of ATP synthase and respiratory chain in mitochondrial membranes: Biochim Biophys Acta, 2009; 1787; 672-80, pmid: 19168025
75. Semenza GL, Defining the role of hypoxia-inducible factor 1 in cancer biology and therapeutics: Oncogene, 2010; 29; 625-34, pmid: 19946328
76. Semenza GL, Tumor metabolism: cancer cells give and take lactate: J Clin Invest, 2008; 118; 3835-37, pmid: 19033652
77. Galluzzi L, Morselli E, Kepp O, Mitochondrial gateways to cancer: Mol Aspects Med, 2010; 31; 1-20, pmid: 19698742
78. Ortega AD, Sánchez-Aragó M, Giner-Sánchez D, Glucose avidity of carcinomas: Cancer Lett, 2009; 276; 125-35, pmid: 18790562
79. Sambrook J, Fritsch EF, Maniatis T: Molecular cloning: a laboratory manual, 1989, New York, Cold Spring Harbor Laboratory Press
80. Livak KJ, Schmittgen TD, Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method: Methods, 2001; 25; 402-8, pmid: 11846609
81. Eisen MB, Spellman PT, Brown PO, Botstein D, Cluster analysis and display of genome-wide expression patterns: Proc Natl Acad Sci USA, 1998; 95; 14863-68, pmid: 9843981
82. Molenaar D, van Berlo R, de Ridder D, Teusink B, Shifts in growth strategies reflect tradeoffs in cellular economics: Mol Syst Biol, 2009; 5; 323, pmid: 19888218
83. Locasale JW, Cantley LC, Altered metabolism in cancer: BMC Biol, 2010; 8; 88, pmid: 20598111
84. Vander Heiden MG, Cantley LC, Thompson CB, Understanding the Warburg effect: the metabolic requirements of cell proliferation: Science, 2009; 324; 1029-33, pmid: 19460998
85. Ding LH, Park S, Peyton M, Distinct transcriptome profiles identified in normal human bronchial epithelial cells after exposure to γ-rays and different elemental particles of high Z and energy: BMC Genomics, 2013; 14; 372, pmid: 23724988
86. Wojtaś B, Pfeifer A, Jarząb M, Unsupervised analysis of follicular thyroid tumours transcriptome by oligonucleotide microarray gene expression profiling: Endokrynol Pol, 2013; 64; 328-34, pmid: 24186587
87. Dong L, Jensen RV, De Rienzo A, Differentially expressed alternatively spliced genes in malignant pleural mesothelioma identified using massively parallel transcriptome sequencing: BMC Med Genet, 2009; 10; 149, pmid: 20043850
88. Ha KC, Lalonde E, Li L, Identification of gene fusion transcripts by transcriptome sequencing in BRCA1-mutated breast cancers and cell lines: BMC Med Genomics, 2011; 4; 75, pmid: 22032724
89. Bergeaud M, Mathieu L, Guillaume A: Cell Cycle, 2013; 12; 2781-93, pmid: 23966169
90. Sorlie T, Perou CM, Tibshirani R, Gene expression patterns of breast carcinomas distinguish tumor subclasses with clinical implications: Proc Natl Acad Sci USA; 98; 10869-74, pmid: 11553815 200
91. Capaldi RA, Aggeler R, Mechanism of the F(1)F(0)-type ATP synthase, a biological rotary motor: Trends Biochem Sci, 2002; 27; 154-60, pmid: 11893513
92. Tsunoda SP, Aggeler R, Yoshida M, Capaldi RA: Proc Natl Acad Sci USA, 2001; 98; 898-902, pmid: 11158567
In Press
Clinical Research
Institutional and Regional Variations in Access to Clinical Trials and Next-Generation Sequencing in Turkis...Med Sci Monit In Press; DOI: 10.12659/MSM.951027
Clinical Research
Low-Intensity Blood Flow-Restricted Multi-Joint Exercise Improves Muscle Function in Patients With Patellof...Med Sci Monit In Press; DOI: 10.12659/MSM.950516
Review article
Musculoskeletal Ultrasound and MRI in the Evaluation of Chemotherapy-Induced Peripheral Neuropathy: A ReviewMed Sci Monit In Press; DOI: 10.12659/MSM.951283
Clinical Research
Sensory Processing, Dissociation, and Affective Symptoms in Misophonia: A Cross-Sectional Study of 35 AdultsMed Sci Monit In Press; DOI: 10.12659/MSM.950938
Most Viewed Current Articles
17 Jan 2024 : Review article 10,187,196
Vaccination Guidelines for Pregnant Women: Addressing COVID-19 and the Omicron VariantDOI :10.12659/MSM.942799
Med Sci Monit 2024; 30:e942799
13 Nov 2021 : Clinical Research 3,708,487
Acceptance of COVID-19 Vaccination and Its Associated Factors Among Cancer Patients Attending the Oncology ...DOI :10.12659/MSM.932788
Med Sci Monit 2021; 27:e932788
14 Dec 2022 : Clinical Research 2,341,643
Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase LevelsDOI :10.12659/MSM.937990
Med Sci Monit 2022; 28:e937990
16 May 2023 : Clinical Research 706,524
Electrophysiological Testing for an Auditory Processing Disorder and Reading Performance in 54 School Stude...DOI :10.12659/MSM.940387
Med Sci Monit 2023; 29:e940387