Luz del Carmen Alarcón-Romero

Prevalence and distribution of human papillomavirus types in cervical cancer, squamous intraepithelial lesions, and with no intraepithelial lesions in women from Southern Mexico

OBJECTIVE This study was to establish the frequency of HPV infection and which HPV types are circulating in women with cervical cancer (CC), with squamous intraepithelial lesions (SIL), and with no intraepithelial lesion (non-IL) from the State of Guerrero in Southern Mexico. Additionally, we investigated the frequency and distribution of HPV 16 intratypic variants found in this population. METHODS This cross-sectional study was conducted in 4150 women who attended five public health centers seeking cytological screening or for gynecological complaints. Pap smears or biopsies, as appropriate, were obtained for cytological and/or histological diagnosis. HPV detection was done by MY09/11 and GP5+/GP6+ PCR systems and typing by restriction fragment length polymorphism or DNA sequencing. HPV 16 variants were also analyzed. RESULTS HPV was found in 100% of CC, 83.5% in HSIL, 94.5% in LSIL, and 40.9% in non-IL. HR-HPV was the most frequent in all groups. HPV 16 was the most commonly identified HPV genotype in CC and HSIL. HPV 33 was the most frequent in LSIL and non-IL. The highest HPV prevalence was found in the youngest women, HR-HPV and HPV 16 were more frequent in women less than 25 years and more than 55 years of age. The HPV 16 variants E, AA-a and AA-c were found, AA-c was found only in CC. CONCLUSION This study contributes to the knowledge of regional prevalence of HPV types in the whole spectrum of disease, which can be useful in the application of prophylactic vaccines against HPV and in the viral screening methods.

Nuclear expression of Rac1 in cervical premalignant lesions and cervical cancer cells

BackgroundAbnormal expression of Rho-GTPases has been reported in several human cancers. However, the expression of these proteins in cervical cancer has been poorly investigated. In this study we analyzed the expression of the GTPases Rac1, RhoA, Cdc42, and the Rho-GEFs, Tiam1 and beta-Pix, in cervical pre-malignant lesions and cervical cancer cell lines.MethodsProtein expression was analyzed by immunochemistry on 102 cervical paraffin-embedded biopsies: 20 without Squamous Intraepithelial Lesions (SIL), 51 Low- grade SIL, and 31 High-grade SIL; and in cervical cancer cell lines C33A and SiHa, and non-tumorigenic HaCat cells. Nuclear localization of Rac1 in HaCat, C33A and SiHa cells was assessed by cellular fractionation and Western blotting, in the presence or not of a chemical Rac1 inhibitor (NSC23766).ResultsImmunoreacivity for Rac1, RhoA, Tiam1 and beta-Pix was stronger in L-SIL and H-SIL, compared to samples without SIL, and it was significantly associated with the histological diagnosis. Nuclear expression of Rac1 was observed in 52.9% L-SIL and 48.4% H-SIL, but not in samples without SIL. Rac1 was found in the nucleus of C33A and SiHa cells but not in HaCat cells. Chemical inhibition of Rac1 resulted in reduced cell proliferation in HaCat, C33A and SiHa cells.ConclusionRac1 is expressed in the nucleus of epithelial cells in SILs and cervical cancer cell lines, and chemical inhibition of Rac1 reduces cellular proliferation. Further studies are needed to better understand the role of Rho-GTPases in cervical cancer progression.

Polymorphisms of the γ-glutamyl hydrolase gene and risk of relapse to acute lymphoblastic leukemia in Mexico

This study evaluated the association of -401C/T and +452C/T polymorphisms of gamma-glutamyl hydrolase and the risk of relapse to acute lymphoblastic leukemia. Genotyping was performed in 70 children with acute lymphoblastic leukemia and 140 healthy children. An association between the -401C/T polymorphism and the risk of relapse was found (p=0.028), patients with the -401T/T genotype have 10.83 (95% CI 1.30-90.14) more chance of a relapse of leukemia. No association was found between the +452C/T polymorphism and the risk of relapse. Therefore, our investigation suggests that the -401C/T polymorphism in the gamma-glutamyl hydrolase may be a factor involved in the generation of relapse to disease in patients with ALL.

Cervical carcinoma in Southern Mexico: Human papillomavirus and cofactors

BACKGROUND This study was conducted to determine human papillomavirus (HPV) types in women with cervical cancer (CC) and normal cervical cytology in the Southern region of Mexico, and to know the contribution of HPV types and cofactors in cervical cancer etiology. METHODS A case-control study was performed in 133 women with CC and 256 controls. HPV detection was done by MY09/11 and GP5+/GP6+ PCR systems and typing by restriction fragment length polymorphism or DNA sequencing. RESULTS HPV was found in 100% of CC and 35.5% of controls. The genotype distribution in CC was: HPV 16 (66.8%), 18 (9%), 31 (7.5%), 45 (4.5%), 58 (3.7%), 69 (3%), 52 (1.6%), 6, 11, 33, 56, and 67 (0.8% each). Among controls, HPV 33 followed by HPV 16 were the most frequent. Cervical cancer was associated with HPV 16 (OR=573.5), HPV 18 (OR=804.4), and undetermined risk HPV (types 67 and 69) (OR=434.3). Age at first intercourse <16 years (OR=9.6) and > or =3 births (OR=16) were significant risk factors for CC. CONCLUSIONS HPV 16, by far, is the most frequent type in CC, HPV 16 and 18 are responsible for 75.8% of the CC cases and high-risk HPV for 94.7%, which is useful data to take into account in vaccination programs. HPV 33 is the most frequent type in controls and high-risk HPV are more common than low-risk HPV.

High miR-24 expression is associated with risk of relapse and poor survival in acute leukemia.

MicroRNAs (miRNAs) play an essential role in the development and progression of acute leukemia (AL). miR-24 promotes the survival of hematopoietic cells. However, little is known concerning the function of miR-24 in human AL. The aim of the present study was to investigate the clinical significance of miR-24 expression in AL. miR-24 expression in 147 patients with AL and 100 healthy individuals was measured by quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). The results showed that compared with the healthy individuals, the expression of miR-24 in AL patients was significantly higher (p<0.001). In addition, miR-24 was expressed at significantly higher levels in acute myeloid leukemia (AML) patients and at significantly lower levels in acute lymphoblastic leukemia (ALL) (p<0.001). More importantly, Kaplan-Meier analysis showed that AL patients with high miR-24 expression tended to have shorter overall survival (p<0.05). In the multivariate analysis stratified for known prognostic variables, miR-24 was identified as an independent prognostic marker. Our data indicated that miR-24 upregulation was associated with poor prognosis in AL. miR-24 was identified for the first time as an independent marker for predicting the clinical outcome of AL patients.

Polymorphisms in the LPL and CETP Genes and Haplotype in the ESR1 Gene Are Associated with Metabolic Syndrome in Women from Southwestern Mexico.

Metabolic syndrome (MetS) is a combination of metabolic disorders associated with an increased risk for cardiovascular disease (CVD). Studies in women reported associations between polymorphisms in ESR1, LPL and CETP genes and MetS. Our aim was to evaluate the association between variants in ESR1, LPL and CETP genes with MetS and its components. Four hundred and eighty women were analyzed, anthropometric features and biochemical profiles were evaluated, and genotyping was performed by real-time PCR. We found an association with elevated glucose levels (odds ratio (OR) = 2.9; p = 0.013) in carrying the AA genotype of rs1884051 in the ESR1 gene compared with the GG genotype, and the CC genotype of rs328 in the LPL gene was associated with MetS compared to the CG or GG genotype (OR = 2.8; p = 0.04). Moreover, the GA genotype of rs708272 in the CETP gene is associated with MetS compared to the GG or AA genotype (OR = 1.8; p = 0.006). In addition the ACTCCG haplotype in the ESR1 gene is associated with a decrease in the risk of MetS (OR = 0.02; p < 0.001). In conclusion, our results show the involvement of the variants of ESR1, LPL and CETP genes in metabolic events related to MetS or some of its features.

Risk of progression of early cervical lesions is associated with integration and persistence of HPV-16 and expression of E6, Ki-67, and telomerase.

Background: Low-grade squamous intraepithelial lesions (LSIL) are the earliest lesions of the uterine cervix, the persistence and integration of high-risk human papillomavirus (HR-HPV) as type 16, which promotes the development of more aggressive lesions. Aim: To select more aggressive lesions with tendency to progress to invasive cervical cancer. Materials and Methods: A total of 75 cytological specimens in liquid base (Liqui-PREP) were analyzed: 25 specimens were with no signs of SIL (NSIL) and without HPV; 25 NSIL with HPV-16, and 25 with both LSIL and HPV-16. The expression of Ki-67, telomerase, and viral E6 was evaluated by immunocytochemistry; and the detection of viral DNA was done by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLPs) for genotyping or sequencing of HPV-16. The physical state of HPV-16 was evaluated by in situ hybridization with amplification with tyramide. Results: Of the total group, 58.6% had LSIL associated with persistence and of these 59.3% was associated with integrated state of HPV as intense expression of E6, Ki-67 (P = 0.013, P = 0.055) has except for the expression of telomerase present a non-significant association (P<0.341). Conclusions: Overexpression of E6 and Ki-67 is associated with the integration of HPV-16, favoring viral persistence, and increasing the risk of progression in women with NSIL and LSIL.

AgNOR polymorphism association with squamous intraepithelial lesions and invasive carcinoma with HPV infection

OBJECTIVE Evaluate the relationships between AgNORs polymorphisms and squamous intraepithelial lesions (SIL) and squamous cell carcinoma (SCC) with HPV infection. MATERIALS AND METHODS A study was carried out on sixty women from the state of Guerrero, Mexico. HPV detection was performed by PCR. AgNORs were identified by argentic impregnation. One hundred cells per slide were counted and classified according to the polymorphism of AgNORs dots; typical (spherical) and atypical (large, kidney-shaped and clustered). RESULTS A total of 100% of the cases were positive for HPV infection. Nine different high-risk HPV genotypes were found, type 16 was the most common (48.6%). The AgNORs showed a significant decrease in spherical shape according to neoplastic development. The three atypical shapes showed a significant increase in SIL and SCC (p-trend<0.001). CONCLUSIONS AgNORs polymorphism rises progressively according to the grade of histological lesions that can be useful as a prognosis for progression of SCC.

Changes in global gene expression profiles induced by HPV 16 E6 oncoprotein variants in cervical carcinoma C33-A cells.

We analyzed the effects of the expression of HPV 16 E6 oncoprotein variants (AA-a, AA-c, E-A176/G350, E-C188/G350, E-G350), and the E-Prototype in global gene expression profiles in an in vitro model. E6 gene was cloned into an expression vector fused to GFP and was transfected in C33-A cells. Affymetrix GeneChip Human Transcriptome Array 2.0 platform was used to analyze the expression of over 245,000 coding transcripts. We found that HPV16 E6 variants altered the expression of 387 different genes in comparison with E-Prototype. The altered genes are involved in cellular processes related to the development of cervical carcinoma, such as adhesion, angiogenesis, apoptosis, differentiation, cell cycle, proliferation, transcription and protein translation. Our results show that polymorphic changes in HPV16 E6 natural variants are sufficient to alter the overall gene expression profile in C33-A cells, explaining in part the observed differences in oncogenic potential of HPV16 variants.

Differential proteins among normal cervix cells and cervical cancer cells with HPV-16 infection, through mass spectrometry-based Proteomics (2D-DIGE) in women from Southern México

BackgroundCervical cancer (CC) is the fourth most common cancer in women worldwide with an estimated 528,000 new cases in 2012. The same year México had an incidence of 13,960 and a mortality of 4769 cases. There are several diagnosis methods of CC; among the most frequents are the conventional Pap cytology (Pap), colposcopy, and visual inspection with acetic acid (VIA), histopathological examination, tests of imaging and detection of high-risk papilloma virus (HR-HPV) with molecular tests (PCR, hybridization, sequencing). Proteomics is a tool for the detection of new biomarkers that can be associated with clinical stage, histological type, prognosis, and/or response to treatment. In this study we performed a comparative analysis of CC cells with normal cervical cells. The proteomic analysis was carried out with the fluorescent two-dimensional electrophoresis (2D-DIGE) technique to subsequently identify differential protein profiles using Decyder Software, and the selected proteins were identified by Mass Spectrometry (MALDI-TOF).ResultsThe proteins that showed an increased expression in cervical cancer in comparison with normal cervix cells were: Mimecan, Actin from aortic smooth muscle and Lumican. While Keratin, type II cytoskeletal 5, Peroxiredoxin-1 and 14-3-3 protein sigma showed a decrease in their protein expression level in cervical cancer in comparison with normal cervix cells.ConclusionsThus, this study was successful in identifying biomarker signatures for cervical cancer, and might provide new insights into the mechanism of CC progression.