LUISA LINA VILLA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
LIM/24 - Laboratório de Oncologia Experimental, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/24 - Laboratório de Oncologia Experimental, Hospital das Clínicas, Faculdade de Medicina - Líder
7 resultados
Resultados de Busca
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- Cervical Cancer in Latin America and the Caribbean: The Problem and the Way to Solutions(2012) VILLA, Luisa LinaLatin America and the Caribbean have one of the highest incidence and mortality rates from cervical cancer in the world. In this region, age-adjusted incidence rates range from 20 to 80 per 100,000 women per year. Overall, the mortality rates are extremely high in spite of the availability of Pap screening in several countries. Women from lower socioeconomic status, often less educated, are unaware of cervical cancer screening or have no access to it. Despite the efforts to reorganize screening programs in the region, in a few countries, only a slight decrease in cervical cancer mortality has been observed. New modalities for primary and secondary screening should be evaluated and disseminated, including HPV testing and vaccination against the most common HPV types. HPV prophylactic vaccines were approved in most Latin American countries, but only few are considering its implementation in national immunization programs. Besides cost and other logistical issues, lack of recommendation by policy makers or lawmakers is deterring the introduction of HPV vaccines in the region. Furthermore, studies conducted in the region have indicated that HPV vaccination only or vaccination supplemented with screening may be considered a cost-effective strategy to reduce mortality by cervical cancer. Cancer Epidemiol Biomarkers Prev; 21(9); 1409-13. (C) 2012 AACR.
- Identification of Novel Cellular Transcription Factors that Regulate Early Promoters of Human Papillomavirus Types 18 and 16(2012) SICHERO, Laura; SIMAO SOBRINHO, Joao; VILLA, Luisa LinaBackground. The long control region (LCR) of human papillomavirus (HPV) regulates early gene transcription by interaction with several viral and cellular transcription factors (TFs). Methods. To identify novel TFs that could influence early expression of HPV type 18 (HPV-18) and HPV type 16 (HPV-16), a high-throughput transfection array was used. Results. Among the 704 TFs tested, 28 activated and 36 inhibited the LCR of HPV-18 by more than 2-fold. For validation, C33 cells were cotransfected with increasing amounts of selected TF expression plasmids in addition to LCR-luciferase vectors of different molecular variants of HPV-18 and HPV-16. Among the TFs identified, only GATA3, FOXA1, and MYC have putative binding sites within the LCR sequence, as indicated using the TRANSFAC database. Furthermore, we demonstrated FOXA1 and MYC in vivo binding to the LCR of both HPV types using chromatin immunoprecipitation assay. Conclusions. We identified new TFs implicated in the regulation of the LCR of HPV-18 and HPV-16. Many of these factors are mutated in cancer or are putative cancer biomarkers and could potentially be involved in the regulation of HPV early gene expression.
conferenceObject Role of Monocarboxylate Transporters (MCTs) in the Regulation of the Metabolic Profile of Cervical Cancer Cells by Hypoxia(2012) PINHEIRO, C.; SANTOS, F.; MIRANDA-GONCALVES, V.; BOCCARDO, E.; LEPIQUE, A. P.; LONGATTO-FILHO, A.; VILLA, L. L.; BALTAZAR, F.Background: Due to the high growth rates of some tumors, cells are exposed to hypoxia, leading to a metabolic switch from oxidative phosphorylation to glycolysis. High glycolytic rates, in turn, lead to production of important amounts of lactate, which are exported to the extracellular milieu, contributing to the acidic microenvironment. Low oxygen concentrations lead to stabilization of hypoxia-inducible factor 1 alpha (HIF-1a), which regulates the expression of several glycolytic markers, as well as pH regulators. Thus, monocarboxylate transporters (MCTs) by mediating the co-transport of lactate with a proton, allow the maintenance of the glycolytic phenotype and intracellular pH, contributing to the tumour acidic microenvironment. However, MCT regulation by hypoxia is not fully understood, being sometimes controversial such as the case of MCT1. Aims: We aimed to characterize the expression of MCT1 and MCT4 and other glycolytic markers, as well as lactate transport activity under hypoxia conditions. The sensitivity of uterine cervix tumour cells to the MCT1 inhibitor CHC (a-cyano-4-hydroxycinnamic acid) was compared between normoxic and hypoxic conditions. Material and Methods: Hypoxia was induced by incubation of human cervical cancer cell lines in a hypoxic chamber (<1% O2). Expression of MCT1, MCT4, CD147, GLUT-1, CAIX and LDH was evaluated by immunocytochemistry and Western blot. Glycolytic metabolism was assessed through quantification of glucose consumption and lactate production. The effect of CHC on cell biomass was performed through the Sulforhodamine B assay. Results and Discussion: In general, the expression of the glycolytic metabolic markers GLUT-1, CAIX and LDH increased with hypoxia, which was accompanied by an increase in MCT1 expression in C33 cells and increased plasma membrane expression of MCT1 of SiHa cells. However, the expected increase in MCT4 expression was not observed. Interestingly, the expression of the MCT1/4 chaperone CD147 decreased in C33 and SiHa cells, pointing to the possible association with a different chaperone. Consistent with the increase in MCT1 expression, the sensitivity to CHC decreased in hypoxic conditions. Conclusion: We showed that hypoxia upregulates the expression of MCT1 in cervical cancer cells, rather than MCT4, and decreased the sensitivity to the MCT1 inhibitor CHC. These findings provide evidence for MCT regulation by hypoxia in cervical cancer and for the role of MCT1 in glycolytic metabolism. Acknowledgements: Part of this work was supported by FAPESP-São Paulo Research Foundation: 2008/03232−1 and the FCT grant ref. PTDC/SAU-FCF/104347/2008, under the scope of 'Programa Operacional Temático Factores de Competitividade' (COMPETE) of ‘Quadro Comunitário de Apoio III’ and co-financed by Fundo Comunitário Europeu FEDER.- Ricardo Renzo Brentani: In Memoriam (1937-2011) Obituary(2012) VILLA, Luisa L.; FRANCO, Eduardo L.
- Oncogenic potential diverge among human papillomavirus type 16 natural variants(2012) SICHERO, Laura; SIMAO SOBRINHO, Joao; VILLA, Luisa LinaWe compared E6/E7 protein properties of three different HPV-16 variants: AA. E-P and E-350G. Primary human foreskin keratinocytes (PHFK) were transduced with HPV-16 E6 and E7 and evaluated for proliferation and ability to grow in soft agar. E-P infected keratinocytes presented the lowest efficiency in colony formation. AA and E-350G keratinocytes attained higher capacity for in vitro transformation. We observed similar degradation of TP53 among HPV-16 variants. Furthermore, we accessed the expression profile in early (p5) and late passage (p30) transduced cells of 84 genes commonly involved in carcinogenesis. Most differences could be attributed to HPV-16 E6/E7 expression. In particular, we detected different expression of ITGA2 and CHEK2 in keratinocytes infected with AA and AA/E-350G late passage cells, respectively, and higher expression of MAP2K1 in E-350G transduced keratinocytes. Our results indicate differences among HPV-16 variants that could explain, at least in part, differences in oncogenic potential attributed to these variants.
- Immunomarkers in Gynecologic Cytology: The Search for the Ideal 'Biomolecular Papanicolaou Test'(2012) PINTO, Alvaro P.; DEGEN, Martin; VILLA, Luisa Lina; CIBAS, Edmund S.Harnessing the knowledge we have gained on the cell cycle disruption caused by human papillomaviruses (HPV) will likely lead to improved screening modalities for cervical cancer and its precursors. An easily applied biomarker that has high specificity and sensitivity would represent an attractive alternative or complement to cytology and HPV testing. To date, a number of promising markers have been investigated. These include p16(IN4A), MIB-1, BD-ProEx C, and U. Newer possibilities involve a variety of gene products associated with aberrations of chromosome 3q, such as telomerase, p63, and PIK3CA, as well the combination of biomarkers such as p16(INK4A) and MIB-1 in the same assay. Although none of them has yet been incorporated into screening algorithms or found its way into routine practice, their performance characteristics remain a focus of current investigations. This review summarizes what we know and where we hope to go in translating basic pathobiology into clinical practice.
conferenceObject Exploring the ""Warburg Effect"" for Cancer Therapy - Targeting Lactate Transport in Cervical Cancer(2012) PINHEIRO, C.; SANTOS, F.; MIRANDA-GONCALVES, V.; PINHEIRO, S.; BOCCARDO, E.; LEPIQUE, A. P.; LONGATTO-FILHO, A.; VILLA, L. L.; BALTAZAR, F.Introduction: The Warburg effect, which consists in the up-regulation of the glycolytic metabolism, even in the presence of oxygen, has been described as an important adaptive mechanism to overcome intermittent hypoxia in pre-malignant lesions. In this context, monocarboxylate transporters (MCTs) emerge as important players due to their dual function as lactate exporters and tumour intracellular pH regulators. We have recently described the up-regulation of monocarboxylate transporter 1 (MCT1) along the progression towards invasive cervical carcinoma. Therefore, we aimed to evaluate the role of MCTs in cervical cancer survival and aggressiveness. Material and Methods: The metabolic profile of the human cervical cancer cell lines SiHa, CaSki, HeLa, Sw756, C33 and HaCat was characterised by quantification of lactate production and glucose consumption as well as evaluation of the expression of different key metabolic proteins. Additionally, MCT1 activity was inhibited using the classical inhibitor alpha-cyano-4-hydroxycinnamate (CHC) and the inhibitory effects were estimated on cell biomass (Sulforhodamine B assay), cell proliferation (BrdU incorporation), induction of apoptosis (Annexin V/PI), cell migration (‘wound healing assay’) and cell invasion (matrigel invasion chamber). Statistical analysis was performed using the GraphPad statistical software. Results and Discussion: Glucose consumption and lactate production varied among cell lines, with CaSki, HeLa and HaCat being the most glycolytic cell lines and SiHa showing the lowest rates of glucose consumption and lactate production.WhenexposingcervicalcancercellstoCHC,wefoundasignificant decrease in total cell biomass, proliferation, migration and invasion, but little effect on cell death. Further MCT1 silencing studies (shMCT1) are being conducted to validate the role of MCT1 in cervical cancer. Conclusions: In this study, we characterised for the first time the effect of MCT1 inhibition in cervical cancer cells’ survival and aggressiveness. The results herein presented point at MCT1 as a promising therapeutic target for cervical cancer therapy. Acknowledgements: Part of this work was supported by the FAPESP - São Paulo Research Foundation grant ref. 2008/03232−1 and the FCT grant ref. PTDC/SAU-FCF/104347/2008, under the scope of “Programa Operacional Temático Factores de Competitividade” (COMPETE) of “Quadro Comunitário de Apoio III” and co-financed by Fundo Comunit ́ario Europeu FEDER.