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Lactate is a ubiquitous molecule in cancer. In this exploratory study, our aim was to test the hypothesis that lactate could function as an oncometabolite by evaluating whether lactate exposure modifies the expression of oncogenes, or genes encoding transcription factors, cell division, and cell proliferation in MCF7 cells, a human breast cancer cell line. Gene transcription was compared between MCF7 cells incubated in (a) glucose/glutamine-free media (control), (b) glucose-containing media to stimulate endogenous lactate production (replicating some of the original Warburg studies), and (c) glucose-containing media supplemented with L-lactate (10 and 20 mM). We found that both endogenous, glucose-derived lactate and exogenous, lactate supplementation significantly affected the transcription of key oncogenes (MYC, RAS, and PI3KCA), transcription factors (HIF1A and E2F1), tumor suppressors (BRCA1, BRCA2) as well as cell cycle and proliferation genes involved in breast cancer (AKT1, ATM, CCND1, CDK4, CDKN1A, CDK2B) (0.001 < p < 0.05 for all genes). Our findings support the hypothesis that lactate acts as an oncometabolite in MCF7 cells. Further research is necessary on other cell lines and biopsy cultures to show generality of the findings and reveal the mechanisms by which dysregulated lactate metabolism could act as an oncometabolite in carcinogenesis.

Lactate is a ubiquitous molecule in cancer. In this exploratory study, our aim was to test the hypothesis that lactate could function as an oncometabolite by evaluating whether lactate exposure modifies the expression of oncogenes, or genes encoding transcription factors, cell division, and cell proliferation in MCF7 cells, a human breast cancer cell line. Gene transcription was compared between MCF7 cells incubated in (a) glucose/glutamine-free media (control), (b) glucose-containing media to stimulate endogenous lactate production (replicating some of the original Warburg studies), and (c) glucose-containing media supplemented with L-lactate (10 and 20 mM). We found that both endogenous, glucose-derived lactate and exogenous, lactate supplementation significantly affected the transcription of key oncogenes (MYC, RAS, and PI3KCA), transcription factors (HIF1A and E2F1), tumor suppressors (BRCA1, BRCA2) as well as cell cycle and proliferation genes involved in breast cancer (AKT1, ATM, CCND1, CDK4, CDKN1A, CDK2B) (0.001 < p < 0.05 for all genes). Our findings support the hypothesis that lactate acts as an oncometabolite in MCF7 cells. Further research is necessary on other cell lines and biopsy cultures to show generality of the findings and reveal the mechanisms by which dysregulated lactate metabolism could act as an oncometabolite in carcinogenesis.

Lactate is a ubiquitous molecule in cancer. In this exploratory study, our aim was to test the hypothesis that lactate could function as an oncometabolite by evaluating whether lactate exposure modifies the expression of oncogenes, or genes encoding transcription factors, cell division, and cell proliferation in MCF7 cells, a human breast cancer cell line. Gene transcription was compared between MCF7 cells incubated in (a) glucose/glutamine-free media (control), (b) glucose-containing media to stimulate endogenous lactate production (replicating some of the original Warburg studies), and (c) glucose-containing media supplemented with L-lactate (10 and 20 mM). We found that both endogenous, glucose-derived lactate and exogenous, lactate supplementation significantly affected the transcription of key oncogenes (MYC, RAS, and PI3KCA), transcription factors (HIF1A and E2F1), tumor suppressors (BRCA1, BRCA2) as well as cell cycle and proliferation genes involved in breast cancer (AKT1, ATM, CCND1, CDK4, CDKN1A, CDK2B) (0.001 < p < 0.05 for all genes). Our findings support the hypothesis that lactate acts as an oncometabolite in MCF7 cells. Further research is necessary on other cell lines and biopsy cultures to show generality of the findings and reveal the mechanisms by which dysregulated lactate metabolism could act as an oncometabolite in carcinogenesis.

Regeneracija in vitro gajenog biljnog tkiva kontrolisana je regulatorima rastenja, naročito citokininima i auksinima. Egzogeno primenjeni biljni regulatori rastenja mogu interagovati sa endogenim biljnim hormonima i uticati na njihovu biosintezu ili distribuciju, odnosno menjati hormonalnu homeostazu koja utiče na razviće in vitro. Proces regeneracije biljaka in vitro podrazumeva intenzivne ćelijske deobe, a centralnu ulogu u kontroli ćelijskog ciklusa i razvića organa imaju kompleksi ciklina i kinaza zavisnih od ciklina na čiju sintezu, odnosno aktivnost, utiču pomenuti biljni hormoni. U tom smislu, ciljevi ovog rada bili su uspostavljanje efikasnih protokola za regeneraciju biljaka kelerabe (Brassica oleracea L. var. gongylodes) in vitro, sa posebnim osvrtom na identifikaciju i kvantifikaciju različitih grupa citokinina i indol-3-sirćetne kiseline (IAA) u eksplantatskim tkivima sa regenerisanim izdancima, kao i analiziranje obrazaca i intenziteta ekspresije gena koji kodiraju cikline i kinaze zavisne od ciklina tokom de novo organogeneze izdanaka. Efikasan sistem za repetitivnu somatsku embriogenezu (SE) kod kelerabe, sorta Bečka Plava (BP), je uspostavljen iz nezrelih zigotskih embriona. Najveća frekvencija SE detektovana je kod nezrelih zigotskih embriona u ranom kotiledonarnom stadijumu razvića gajenih na hranljivoj podlozi bez regulatora rastenja. Uspešna indukcija de novo organogeneze izdanaka kelerabe, sorte BP i Bečka Bela (BB), postignuta je kod odsečaka hipokotila i intaktnih klijanaca, na podlogama sa pojedinačnim citokininima (CK): 6-benzilaminopurin (BAP), tidiazuron (TDZ), transzeatin (transZ) ili cis-zeatin (cisZ). Frekvencija regeneracije kao i vijabilnost regenerisanih izdanaka obe sorte je bila veća kod intaktnih klijanaca, dok su među primenjenim citokininima BAP i TDZ bili najefikasniji u indukciji de novo organogeneze. Kvantifikacija endogenog sadržaja citokinina i IAA u odsečcima hipokotila sa regenerisanim izdancima (HRI) kao i u intaktnim kl, vitro plant regeneration is under control of plant growth regulators (PGRs), especially cytokinins and auxins. Exogenously applied PGRs can affect the homeostasis of endogenous plant hormones by influencing their biosynthesis and distribution, subsequently altering in vitro development. Intensive cell divisions represent the basis of in vitro plant regeneration, and they are controlled by complexes of cyclins and cyclin-dependent kinases. The activity of these complexes during cell cycle and organ development is affected by plant hormones. Respecting this, the aims of this study were developing efficient protocols for in vitro regeneration of kohlrabi (Brassica oleracea L. var. gongylodes) with an emphasis on identification and quantification of different groups of endogenous cytokinins and indole-3-acetic acid (IAA) in explant tissue with respective regenerated shoots, as well as analyzing expression of genes encoding cyclins and and cyclin-dependent kinases during de novo shoot organogenesis. Efficient system for repetitive somatic embryogenesis (SE) was developed for kohlrabi cv. Vienna Purple (VP) using immature zygotic embryos. The highest frequency of SE was obtained from immature zygotic embryos at the early cotyledonary stage grown on PGR-free medium. Successful induction of de novo shoot organogenesis in kohlrabi cv VP and cv. Vienna White (VW) was achived using hypocotyl explants and intact seedlings, cultivated on media supplemented with single cytokinin (CK): 6-benzylaminopurine (BAP), thidiazuron (TDZ), trans-zeatin (transZ) or cis-zeatin (cisZ). Higher frequency of shoot regeneration as well as viability of regenerated shoots was detected for intact seedlings, with BAP and TDZ being the most efficient in de novo organogenesis induction. Quantification of endogenous cytokinin and IAA contents in both hypocotyl explants and seedlings with regenerated shoots (HRSs and SRSs, respectively) suggested that the observed differences in organogenic response betw

Atherosclerosis is characterized by excessive proliferation of neointimal leukocytes and vascular smooth muscle cells (VSMCs). In mice, the manipulation of cell cycle inhibitors such as CDKN1B (p27) and CDKN1A (p21) modifies the risk of developing atherosclerosis. In humans, CDKN1A, CDKN1B and CDKN1C (p57) are differentially expressed in normal versus atherosclerotic vessels. A DNA‑polymorphism within the CDKN1B promoter has been associated with myocardial infarction (MI). In the present study, we analyzed the effect of CDKN1A, CDKN1C and CDKN2A (p16) polymorphisms on MI‑risk. A total of 316 patients (all male, < 55 years) and 434 controls were genotyped, and the allele and genotype frequencies were compared between the two groups. Two CDKN1C polymorphisms, a promoter GT‑repeat and a variable number of repeats of the amino acid PAPA‑motif, were associated with MI. The presence of two alleles ≤ 11‑repeats (9/11, 10/11 and 11/11 genotypes) was significantly less frequent among patients (p < 0.001). This difference was also significant when analyzing the subpopulation of smokers (p = 0.004), suggesting a protective role for these low‑repeat genotypes (OR = 0.49, 95%CI = 0.32–0.73). The PAPA‑BB homozygotes were significantly less frequent in patients, but this could be attributed to a linkage disequilibrium between the 11‑repeats and B alleles. No significantly different frequencies between patients and controls for the four CDKN1A (‑1026A/G, ‑754G/C, ‑369G/C and Ser31Arg) and the three CDKN2A (‑523 G/A, +22 G/A and Ala148Thr) polymorphisms was found. In conclusion, we provide here genetic evidence for the association between DNA‑variants in the CDKN1C/p57 gene and the risk of atherosclerosis and MI.