The Unexplored Wound Healing Activity of Urtica dioica L. Extract: An In Vitro and In Vivo Study.

Wound healing is a great challenge in many health conditions, especially in non-healing conditions. The search for new wound healing agents continues unabated, as the use of growth factors is accompanied by several limitations. Medicinal plants have been used for a long time in would healing, despite the lack of scientific evidence veryfying their efficacy. Up to now, the number of reports about medicinal plants with wound healing properties is limited. Urtica dioica L. is a well-known plant, widely used in many applications. Reports regarding its wound healing potential are scant and sparse. In this study, the effect of an Urtica dioica L. extract (containing fewer antioxidant compounds compared to methanolic or hydroalcoholic extracts) on cell proliferation, the cell cycle, and migration were examined. Additionally, antioxidant and anti-inflammatory properties were examined. Finally, in vivo experiments were carried out on full-thickness wounds on Wistar rats. It was found that the extract increases the proliferation rate of HEK-293 and HaCaT cells up to 39% and 30% after 24 h, respectively, compared to control cells. The extract was found to increase the population of cells in the G2/M phase by almost 10%. Additionally, the extract caused a two-fold increase in the cell migration rate of both cell lines compared to control cells. Moreover, the extract was found to have anti-inflammatory properties and moderate antioxidant properties that augment its overall wound healing potential. Results from the in vivo experiments showed that wounds treated with an ointment of the extract healed in 9 days, while wounds not treated with the extract healed in 13 days. Histopathological examination of the wound tissue revealed, among other findings, that inflammation was significantly reduced compared to the control. Urtica dioica L. extract application results in faster wound healing, making the extract ideal for wound healing applications and a novel drug candidate for wound healing.

PAPOLA contributes to cyclin D1 mRNA alternative polyadenylation and promotes breast cancer cell proliferation.

Poly(A) polymerases add the poly(A) tail at the 3' end of nearly all eukaryotic mRNA, and are associated with proliferation and cancer. To elucidate the role of the most-studied mammalian poly(A) polymerase, poly(A) polymerase α (PAPOLA), in cancer, we assessed its expression in 221 breast cancer samples and found it to correlate strongly with the aggressive triple-negative subtype. Silencing PAPOLA in MCF-7 and MDA-MB-231 breast cancer cells reduced proliferation and anchorage-independent growth by decreasing steady-state cyclin D1 (CCND1) mRNA and protein levels. Whereas the length of the CCND1 mRNA poly(A) tail was not affected, its 3' untranslated region (3'UTR) lengthened. Overexpressing PAPOLA caused CCND1 mRNA 3'UTR shortening with a concomitant increase in the amount of corresponding transcript and protein, resulting in growth arrest in MCF-7 cells and DNA damage in HEK-293 cells. Such overexpression of PAPOLA promoted proliferation in the p53 mutant MDA-MB-231 cells. Our data suggest that PAPOLA is a possible candidate target for the control of tumor growth that is mostly relevant to triple-negative tumors, a group characterized by PAPOLA overexpression and lack of alternative targeted therapies.

mTORC2 deploys the mRNA binding protein IGF2BP1 to regulate c-MYC expression and promote cell survival.

mTORC2 promotes cell survival by phosphorylating AKT and enhancing its activity. Inactivation of mTORC2 reduces viability through down-regulation of E2F1 caused by up-regulation of c-MYC. An additional target of mTORC2 is IGF2BP1, an oncofetal RNA binding protein expressed de novo in a wide array of malignancies. IGF2BP1 enhances c-MYC expression by protecting the coding region instability sequence (CRD) of its mRNA from endonucleolytic cleavage. Here we show that repression of mTORC2 signalling and prevention of Ser181 phosphorylation of IGF2BP1 enhanced translation and destabilization of the endogenous c-myc mRNA as well as the mRNA of reporter transcripts carrying the CRD sequence in frame. The consequent increase in c-MYC protein was accompanied by the emergence of an apoptotic c-MYC overexpressing population. On the other hand, preventing phosphorylation of IGF2BP1 on Tyr396 by Src kinase caused the accumulation of translationally silent transcripts through sequestration by IGF2BP1 into cytoplasmic granules. The apoptotic effect of mTORC2 signalling deprivation was augmented when preceded by inhibition of IGF2BP1 phosphorylation by the Src kinase in concert with further increase of c-MYC levels because of enhanced translation of the previously stored mRNA only in the presence of IGF2BP1. Furthermore, the combined administration of mTORC2 and Src inhibitors exhibited synergism in delaying xenograft growth in female NOD.CB17-Prkdcscid/J mice. The above in vitro and in vivo findings may be applied for the induction of targeted apoptosis of cells expressing de novo the oncofetal protein IGF2BP1, a feature of aggressive malignancies resulting in a more focused anticancer therapeutic approach.

Exploring the crosstalk of glycolysis and mitochondrial metabolism in psychiatric disorders and brain tumours.

Dysfunction of metabolic pathways characterises a plethora of common pathologies and has emerged as an underlying hallmark of disease phenotypes. Here, we focus on psychiatric disorders and brain tumours and explore changes in the interplay between glycolysis and mitochondrial energy metabolism in the brain. We discuss alterations in glycolysis versus core mitochondrial metabolic pathways, such as the tricarboxylic acid cycle and oxidative phosphorylation, in major psychiatric disorders and brain tumours. We investigate potential common patterns of altered mitochondrial metabolism in different brain regions and sample types and explore how changes in mitochondrial number, shape and morphology affect disease-related manifestations. We also highlight the potential of pharmacologically targeting mitochondria to achieve therapeutic effects.

Unraveling the Serum Metabolomic Profile of Post-partum Depression.

Post-partum depression (PPD) is a severe psychiatric disorder affecting ∼15% of young mothers. Early life stressful conditions in periconceptual, fetal and early infant periods or exposure to maternal psychiatric disorders, have been linked to adverse childhood outcomes interfering with physiological, cognitive and emotional development. The molecular mechanisms of PPD are not yet fully understood. Unraveling the molecular underpinnings of PPD will allow timely detection and establishment of effective therapeutic approaches. To investigate the underlying molecular correlates of PPD in peripheral material, we compared the serum metabolomes of an in detail characterized group of mothers suffering from PPD and a control group of mothers, all from Heraklion, Crete in Greece. Serum samples were analyzed by a mass spectrometry platform for targeted metabolomics, based on selected reaction monitoring (SRM), which measures the levels of up to 300 metabolites. In the PPD group, we observed increased levels of glutathione-disulfide, adenylosuccinate, and ATP, which associate with oxidative stress, nucleotide biosynthesis and energy production pathways. We also followed up the metabolomic findings in a validation cohort of PPD mothers and controls. To the very best of our knowledge, this is the first metabolomic serum analysis in PPD. Our data show that molecular changes related to PPD are detectable in peripheral material, thus paving the way for additional studies in order to shed light on the molecular correlates of PPD.

Docosahexaenoic Acid Inhibits Proliferation of EoL-1 Leukemia Cells and Induces Cell Cycle Arrest and Cell Differentiation.

Τhe effect of docosahexaenoic acid (DHA, an omega-3 polyunsaturated fatty acid) upon the proliferation of EoL-1 (Eosinophilic leukemia) cell line was assessed, while additional cellular events during the antiproliferative action were recorded. DHA inhibited EoL-1 cells growth dose-dependently by inducing growth arrest at G0/1 phase of the cell cycle. After DHA addition to the cells, the expression of MYC oncogene was decreased, PTAFR-mRNA overexpression was observed which was used as a marker of differentiation, and PLA2G4A-mRNA increase was recorded. The enzymatic activities of phospholipase A2 (PLA2), a group of hydrolytic enzymes, whose action precedes and leads to PAF biosynthesis through the remodeling pathway, as well as platelet activating factor acetylhydrolase (PAFAH) which hydrolyses and deactivates PAF, were also measured. DHA had an effect on the levels of both the intracellular and secreted activities of PLA2 and PAFAH. The inflammatory cytokines IL-6 and TNF-α were also detected in high levels. In conclusion, DHA-induced EoL-1 cells differentiation was correlated with downregulation of MYC oncogene, overexpression of PTAFR and PLA2G4A-mRNAs, increase of the inflammatory cytokines production, and alteration of the enzymatic activities that regulate PAF levels. DHA is a natural substance and the understanding of its action on EoL-1 cells on molecular level could be useful in further investigation as a future therapeutic tool against F/P ⁺ hypereosinophilic syndrome.

Clinical characterization of a novel calcium sensing receptor genetic alteration in a Greek patient with autosomal dominant hypocalcemia type 1.

OBJECTIVE: Autosomal dominant hypocalcemia (ADH) is a rare familial or sporadic syndrome associated with activating mutations in the calcium sensing receptor (CaSR) gene. The aim of this study was to assess the functional significance of a novel CaSR mutation and, moreover, to present the clinical characteristics and the bone mineral density (BMD) progression from early childhood to late puberty in a patient with ADH. DESIGN: Genetic analysis of the CaSR gene was performed in a patient who presented in the neonatal period with hypocalcemic seizures and biochemical features of ADH. The functional impact of the novel mutation identified was assessed in cultured HEK 293T cells, transfected with either the wild type (WT) or mutant CaSR, by evaluating intracellular calcium ([Ca2+]i) influx after stimulation with extracellular calcium (Ca2+). Several BMD measurements were performed during the patient's follow-up until late puberty. RESULTS: A novel CaSR mutation (p.L123S) was identified, which, as demonstrated by functional analysis, renders CaSR more sensitive to extracellular changes of Ca2+ compared with the WT, although the difference is not statistically significant. BMD measurements, from early childhood to late puberty, revealed high normal to elevated BMD. CONCLUSION: We present the first Greek patient, to our knowledge, with sporadic ADH due to a novel gain-of-function mutation of the CaSR gene.

Systematic analysis of the contribution of c-myc mRNA constituents upon cap and IRES mediated translation.

Fine tuning of c-MYC expression is critical for its action and is achieved by several regulatory mechanisms. The contribution of c-myc mRNA regulatory sequences on its translational control has been investigated individually. However, putative interactions have not been addressed so far. The effect of these interactions upon the translatability of monocistronic and bicistronic chimaeric mRNAs, carrying combinations of the c-myc mRNA 5'-untranlated region (UTR), 3'-UTR, and coding region instability element (CRD) was investigated on this study. The presence of the 5'-UTR induced an increase in translatability of 50%. The presence of the CRD element, when in frame, reduced translatability by approximately 50%, regardless of the expression levels of the wild type CRD- binding protein (CRD-BP/IMP1). Conversely, overexpression of a mutated CRD-BP/IMP1 (Y396F) further impeded translation of the chimaeric mRNAs carrying its cognate sequences. The presence of the c-myc 3'-UTR increased translatability by approximately 300% affecting both cap and c-myc internal ribosome entry site (IRES) mediated translation. In addition, 3'-UTR rescued the cap mediated translation in the presence of the polyadenylation inhibitor cordycepin. Furthermore, the 3'-UTR rescued cap mediated translation under metabolic stress conditions and this was enhanced in the absence of a long poly (A) tail.

Expression of Stem Cell Marker Nestin and MicroRNA-21 in Meningiomas.

AIM: Meningiomas are one of the most common benign intracranial tumors, making up nearly one third of all primary intracranial tumors. The majority of meningiomas have benign histological features and total resection is associated with favourable prognosis. Atypical and malignant meningiomas are associated with increased risk of recurrence. In the present study we set out to investigate the role of nestin mRNA levels and miR-21 in meningiomas. MATERIAL AND METHODS: We studied 17 patients with meningiomas that were treated surgically in our institute. Clinical variables that were analyzed were age, sex and histology. The expression of stem cell marker nestin mRNA levels and miR-21 was investigated in tissue samples by qRT-PCR. RESULTS: Considerable levels of both miR-21 and nestin mRNA were found. Atypical and anaplastic meningiomas had higher expression of both miR-21 and nestin compared to benign tumors. Furthermore, a trend towards a positive correlation between miR-21 and nestin mRNA levels was also found. CONCLUSION: Increased miR-21 and nestin mRNA levels were found in anaplastic meningiomas, in which recurrence is common, and the role of miR-21 and Nestin in meningiomas therefore warrants further investigation.

Dipalmitoyl-phosphatidylcholine biosynthesis is induced by non-injurious mechanical stretch in a model of alveolar type II cells.

Dipalmitoylphosphatidylcholine, (DP-PtdCho), the major phospholipid component of lung surfactant is biosynthesized via a de novo pathway, the last step of which is catalyzed by CDP-choline:cholinephosphotransferase (CPT) and two remodeling steps: a deacylation and a reacylation one, catalyzed by an acidic, Ca²âº-independent phospholipase A2 (aiPLA2) and a lyso-phosphatidylcholine acyltransferase (LPCAT), respectively. The aim of our study was to investigate whether a low magnitude, non-injurious static mode of mechanical stretch can induce phosphatidylcholine (PtdCho) biosynthesis and its remodeling to DP-PtdCho in the A549 cell-line, a model of alveolar type II cells. The deformation of A549 cells did not cause any release of lactate dehydrogenase, or phospholipids into the cell culture supernatants. An increase in PtdCho levels was observed after 1 h of static stretching, especially among the DP-PtdCho molecular species, as indicated by targeted lipidomics approach and site-directed fatty acyl-chain analysis. Moreover, although sphingomyelin (CerPCho) levels were unaffected, the DP-PtdCho/CerPCho ratio increased. Induction was observed in CPT, LPCAT and aiPLA2 enzymatic activities and gene expression. Finally, incubation of the cells with MJ33 suppressed aiPLA2 activity and DP-PtdCho production. Our data suggest that mild static mechanical stretch can promote the biosynthesis of PtdCho and its remodeling to DP-PtdCho in lung epithelial cells. Thus, low magnitude stretch could contribute to protective mechanisms rather than to injurious ones.

Study of genetic and epigenetic alterations in urine samples as diagnostic markers for prostate cancer.

BACKGROUND: Early diagnosis of prostate cancer and identification of new prognostic factors remain main issues in prostate cancer research. In this study, we sought to test a panel of cancer-specific markers in urine samples as an aid for early cancer diagnosis. MATERIALS AND METHODS: Sedimented urine samples of 66 candidates for needle biopsy were tested. Real time-polymerase chain reaction (RT-PCR) was applied to detect the expression of transmembrane protease serine-2 and Ets-related gene fusion (TMPRSS2-ERG), Ets-related gene (ERG), prostate cancer antigen-3 (PCA3), and serine peptidase inhibitor kazal type-1 (SPINK1) transcripts. For testing of the methylation status of Glutahione S-tranferase P (GSTP1) and Ras association domain family member-1(RASSF1A) promoter region, methylation-specific PCR (MSP-PCR) was applied. RESULTS: Among the tested parameters, the presence of TMPRSS2-ERG (OR=9.044, 95% CI=2.207-37.066, p=0.002), as well as a positive test result for PCA3 (OR=7.549, 95% CI=1,858-30,672, p=0.005) were associated with the subsequent diagnosis of prostate cancer. A multivariable logistic regression including all the significantly associated variables [prostate-specific antigen (PSA), digital rectal examination (DRE), TMPRSS2-ERG and PCA3], yielded a model with area under the receiver-operating characteristic curve (AUC) =0.894 (95% CI=0.772-1.00). CONCLUSION: A multiplexed quantitative PCR analysis on sedimented urine, in conjunction with the results of serum PSA levels and DRE, has the potential to accurately foresee subsequent needle biopsy outcomes. On the basis of the above, algorithms may be designed to guide decisions for needle biopsy.

Parallel overexpression and clinical significance of kallikrein-related peptidases 7 and 14 (KLK7KLK14) in colon cancer.

Currently available colon cancer (CC) markers lack sensitivity and specificity. Kallikrein-related peptidases (KLKs) present a new class of biomarkers under investigation for diverse diseases, including cancer. KLKs are co-expressed in various tissues participating in proteolytic cascades. KLK7 in human tumours facilitates metastasis by degrading components of the extracellular matrix. KLK14 promotes tumourigenesis by activating proteinase-activated receptors. In the present study we examined the concomitant expression of KLK7 and KLK14 in245 colonic tissue specimens from 175 patients; 70 were pairs of cancerous-normal tissues, 31 were cancerous tissues and 74 were colonic adenomas. We used quantitative real-time PCR and proved that both genes are up-regulated in CC at the mRNA level. Receiver-operating characteristic (ROC) analysis of our results showed that both genes have discriminatory value between CC and adenoma tissues, with KLK14 obtaining greater distinguishing power (area under the curve [AUC]=0.708 for KLK14; AUC=0.669 for KLK7). Current work showed that the two genes are fairly co-expressed in all three types of colon tissues examined (normal rs=0.667, p<0.001, adenomas rs=0.373, p=0.001, carcinomas rs=0.478, p<0.001). KLK14 is associated with shorter disease-free survival (DFS) and overall survival (OS) of patients (p=0.003, p=0.016 respectively), whereas KLK7only with shorter DFS (p=0.004). KLK7 and KLK14 gene expression can be regarded as markers of poor prognosis for CC patients with discriminating power between CC and adenoma patients.

The structure of the 5'-untranslated region of mammalian poly(A) polymerase-alpha mRNA suggests a mechanism of translational regulation.

Poly(A)polymerase-alpha (PAPOLA) has been the most extensively investigated mammalian polyadenylating enzyme, mainly in regard to its multifaceted post-translational regulation. The possibility of translational regulation of this enzyme was addressed. The transcription start site was mapped and two uORFs, highly conserved among several species, were identified in the 211-bp long, GC-rich, 5' UTR of the PAPOLA mRNA. Mutation of the 5' proximal AUG resulted in increased translational efficiency of the adjacent coding sequence, whereas no significant effect was observed after mutation of the second AUG. These observations imply that translational regulation is among the conserved mechanisms regulating PAPOLA expression.

Novel SYT-SSX fusion transcript variants in synovial sarcoma.

Synovial sarcoma (SS) is characterized by the t(X;18)(p11.2;q11.2) chromosomal translocation detected in >95% of cases. Through this translocation, one of the SYT genes, SYT4 on chromosome 18, is fused to one of the SSX genes on chromosome X. SYT4-SSX1 is the most common fusion subtype, present in approximately two thirds of the cases, followed by SYT4-SSX2 and, very rarely, SYT4-SSX4. Variant fusion transcripts occur less often, and most of the reported cases are the result of small insertions. Described here is a novel fusion variant containing a small deletion resulting in an alternative reading frame of the SSX part of the fusion gene. This fusion transcript may provide further insight into the oncogenic function of the SSX partner of the fusion gene.

Expression of oncofetal RNA-binding protein CRD-BP/IMP1 predicts clinical outcome in colon cancer.

The oncofetal CRD-BP/IMP1 RNA binding protein regulates posttranscriptionally a handful of RNA transcripts, implicated in cell adhesion and invadopodia formation and was recently identified as a target of the beta-catenin/Tcf transcription factor that is constitutively activated in colorectal carcinomas (CRCs). The expression of CRD-BP/IMP1 was studied in normal adult intestines and CRCs. In normal mucosa, CRD-BP/IMP1 immunoreactivity was observed in few scattered cells located predominantly at or near the bottom of the crypts, whereas in CRCs the protein was detectable in tumor cells of 50% of the specimens analyzed. CRD-BP/IMP1 mRNA expression was measured by qRT-PCR in 78 CRCs. Thirty-two (41%) of the specimens were negative or had negligible expression, whereas the remaining forty-six (59%) expressed a wide range of CRD-BP/IMP1 mRNA levels. CRD-BP/IMP1 mRNA expression correlated with that of the putative stem/progenitor cell marker Musashi-1 mRNA (p = 0. 035). CRD-BP/IMP1 positive tumors metastasized and/or recurred more frequently (p = 0.001) and its expression defined a group of patients with shorter survival (p = 0.014). Furthermore, in a multivariate analysis CRD-BP/IMP1 expression was found to be an independent predictor of survival (p = 0.015). For stage I & II patients, the differences in metastasis/recurrence and survival rates remained significant (p = 0.001 and 0.033, respectively). These findings indicate that CRD-BP/IMP1 positive tumors exhibit early disease dissemination and unfavorable prognosis.

Cytogenetic manifestations of multiple myeloma heterogeneity.

To investigate the genetic basis of the great heterogeneity observed in the clinical behavior of multiple myeloma (MM), a combined approach of G-banding, interphase fluorescence in situ hybridization (FISH), and multicolor FISH (M-FISH) was employed to analyze 70 samples from 53 patients with MM. G-banding revealed abnormal karyotypes in 77% of the cases. The origin of 31 chromosome markers was identified or revised by M-FISH. Combined metaphase karyotypic data and interphase FISH findings, using the immunoglobulin heavy-chain (IGH), IGH/cyclin D1 gene (CCND1), and D13S319 probes, revealed chromosome abnormalities in all evaluated patients and marked inter- and intratumor cytogenetic heterogeneity in the investigated MM samples. Cytogenetically unrelated clones were detected in 26% of the cases, mostly MM evaluated at diagnosis, whereas cytogenetic clonal evolution, manifested as related clones in 20% of the cases, was associated with disease progression. Among the 14q32 rearrangements, present in 66% of the cases, at least three cytogenetic subsets could be identified: one with t(11;14), usually without 13q14 deletion; another with other IGH changes, often 13q14 deletion, and hypodiploid modal chromosome number; and a third without changes in 14q32 but with abnormalities of chromosome 17. The correlation found between cytogenetic and clinicopathologic characteristics provided support for the concept that general genomic features in conjunction with specific chromosome rearrangements define the malignant phenotype in the various subsets of MM.

Expression of the RNA-binding protein CRD-BP in brain and non-small cell lung tumors.

The coding region determinant-binding protein (CRD-BP) is an RNA binding protein that recognizes c-myc and IGF-II leader 3 mRNAs as well as the oncofetal H19 RNA. CRD-BP exhibits an oncofetal pattern of expression and has been detected in the majority of colon (81%), breast (58.5%) and sarcoma (73%) tumors. The study of CRD-BP expression was extended in brain tumors and Non small cell lung (NSCL) carcinomas and 12/24 malignant, 2/5 benign neuroepithelial tumors and 4/15 of NSCL carcinomas were found positive. All normal matching tissues tested were found negative. The highest frequency (60%) of CRD-BP positive tumors was observed in meningiomas, either benign (11/18) or atypical (3/3). These findings confirm that CRD-BP expression is restricted in tumors; the frequency of its de novo expression may vary according to tumor type and appears to be an early event in the transformation process.

Cytogenetic profile of unknown primary tumors: clues for their pathogenesis and clinical management.

Unknown primary tumors (UPTs) represent an entity of great clinical and biological interest, whose origin cannot be determined even after medical workup. To better understand their pathogenesis by outlining their genetic composition, 20 UPTs were investigated by G-banding, supplemented with Fluorescence In Situ Hybridization and Comparative Genomic Hybridization analyses. The data obtained were sufficient to reach a diagnosis in five cases-four lymphomas and one Ewing sarcoma-demonstrating that in a subset of UPTs, cytogenetics can be an adjunct for differential diagnosis. In the remaining 15 UPTs, an aggressive cytogenetic pattern was revealed. The most frequently rearranged chromosome regions were 1q21, 3p13, 6q15-23, 7q22, 11p12-5, and 11q14-24, pinpointing gene loci probably associated with the peculiar pathogenesis of UPTs. The preferential involvement of 4q31, 6q15, 10q25, and 13q22 in adenocarcinomas (whereas 11q22 is involved in the rest of the carcinomas)-in addition to the marked divergence in the mean average of chromosomal changes, 16 and 3, respectively-demonstrates genotypic differences between the two histologic subgroups. Furthermore, the significantly shorter survival in cases displaying massive chromosome changes compared with those having a few changes indicates that the cytogenetic pattern might be used as a tool to assess prognosis in UPTs, even without the detection of their primary site.

Telomerase activity and genetic alterations in primary breast carcinomas.

It has been proposed that the structural and numerical chromosome abnormalities recorded in breast cancer could be the result of telomere dysfunction and that telomerase is activated de novo to provide a survival mechanism curtailing further chromosomal aberrations. However, recent in vivo and in vitro data show that the ectopic expression of telomerase promotes tumorigenesis via a telomere length-independent mechanism. In this study, the relation between telomerase expression and the extent of chromosomal aberrations was investigated in 62 primary breast carcinomas. Telomerase activity was measured using a polymerase chain reaction-based telomeric repeat amplification protocol assay and 92% of the tumors were found to express telomerase with a relative activity ranging from 0 to 3839.6. Genetic alterations were determined by G-banding and comparative genomic hybridization analysis and 97% of the tumors exhibited chromosomal aberrations ranging from 0 to 44 (average: 10.98). In the overall series, the relationship between telomerase activity levels and genetic changes could be best described by a quadratic model, whereas in tumors with below-average genetic alteration numbers, a significant positive association was recorded between the two variables (coefficient=0.374, P=.017). The relationship between telomerase activity levels and the extent of genetic alteration may reflect the complex effect of telomerase activation upon tumor progression in breast carcinomas.