Miriam Guido

Universidad Nacional Autónoma de México | UNAM · Departament of Molecular Biology and Biotechnology

An important characteristic of cancers associated with high-risk human papillomaviruses (HR-HPV) is the inability of p53 to activate apoptosis due to the effect of the oncoprotein E6. However, the effect of HPV-16 E6 splice variant isoforms (namely E6*I and E6*II), their interaction with the existing p53 isoforms, and their influence on apoptosis i...

Background: Survival of patients with oral squamous cell carcinoma (OSCC) is generally low, with the likelihood of locoregional recurrence or disease progression (LR/DP). Knowledge of prognostic factors for survival is key to achieving an understanding and increased survival. The present study aimed to identify prognostic factors for patients with...

Persistent infections with some types of human papillomavirus (HPV) constitute the major etiological factor for cervical cancer development. Nanog, a stem cell transcription factor has been shown to increase during cancer progression. We wanted to determine whether Nanog could modulate transcription of E6 and E7 oncogenes. We used luciferase report...

Background: Incidence of anal and oral infections with Human Papillomavirus (HPV) is increasing, particularly among Human Immunodeficiency Virus-positive (HIV+) men. HPV type 16 has exhibited the highest incidence and only limited data is available on other prevalent types, variants of HPV16, as well as associated factors. We were interested in id...

Background: Although HPV emerged as a crucial carcinogenic and prognostic biomarker in head and neck cancer, and considering the increase in HPV-associated oral lesions (HPV-OLs) in HIV individuals, molecular information about HPV-OLs is scarce; thus, our aim was to determine viral loads in HPV-OLs from HIV/AIDS individuals. Methods: HIV/AIDS su...

Development of cervical cancer is associated with persistent infections by high-risk human papillomavirus (HPV). Although current HPV L1-based prophylactic vaccines prevent infection, they do not help to eliminate prevalent infections or lesions. Our aims were (i) to generate a vaccine combining prophylactic and therapeutic properties by producing...

Since the introduction of highly active antiretroviral therapy (HAART), an increase in the frequency of human papillomavirus-associated oral lesions (HPV-OL) has been observed. Thus, the aim of this study was to determine the prevalence and factors associated with HPV-OL in Mexican HIV-infected patients, as well as its genotyping, in the HAART era....

All major ABO blood alleles are found in most populations worldwide, whereas the majority of Native Americans are nearly exclusively in the O group. O allele molecular characterization could aid in elucidating the possible causes of group O predominance in Native American populations. In this work, we studied exon 6 and 7 sequence diversity in 180...

The aim of the present study was to determine the association of high-risk human papillomavirus (HR-HPV) in Mexican individuals with oral squamous cell carcinoma (OSCC) and their association with various risk factors. We designed a matched case-control study. Cases were individuals with newly diagnosed OSCC, age- and sex-matched with controls (1:4)...

Infection with human papillomavirus-16 (HPV-16) is the cause of most anogenital carcinomas. This virus is also detected in about 20% of all head and neck squamous cell carcinomas. While there is strong evidence for a causal etiological role in the case of tonsillar carcinomas, causal association with malignant lesions of the oral cavity is not yet...

Our objective was to determine the association between viral load of high risk human papilloma virus (HPV) using the Hybrid Capture II (HC II) system and cervical intraepithelial neoplasia (CIN) lesion stage. A total of 182 consecutive women with confirmed diagnoses of CIN 1-3 and 182 healthy women with negative Pap were included. All subjects unde...

To determine the high risk HPV (HR-HPV) association with Cervical Intraepithelial Neoplasia (CIN) in women of two Dysplasia Clinics in Mexico City. Prolective case-control study was done. Women with and without security affiliation attended in Instituto Mexicano del Seguro Social (Hospital 1) and Hospital General de México (Hospital 2) were include...

Human-papillomavirus (HPV)-E2 protein is involved in gene-expression regulation and replication of HPV genome. Disruption of the E2 gene during viral integration has been proposed as a mechanism of tumoral progression, since the expression of E6/E7 viral oncogenes is allowed. However, retention of E1/E2 genes and high viral amplification are freque...

Human-papillomavirus (HPV)-E2 protein is involved in gene-expression regulation and replication of HPV genome. Disruption of the E2 gene during viral integration has been proposed as a mechanism of tumoral progression, since the expression of E6/E7 viral oncogenes is allowed. However, retention of E1/E2 genes and high viral amplification are freque...

Micromanipulation of living cells was first used in electrophysiology studies during the first half of this century. Reliable techniques for intracellular recording were developed in the late 1940s. Less than one decade later, similar techniques were applied to perform direct transfer of biological material into cells (see Chambers and Chambers 196...

Human papillomavirus (HPV) DNA sequences are found in most carcinomas originating from the uterine cervix. HPV E6 and E7 oncogenes have been shown to cooperate with ras oncogenes to fully transform human epithelial cells. We investigated the effect of the Ha-ras oncogene on the transcriptional activity of HPV-18 and found that it induced the transc...

Human papillomavirus (HPV) DNA sequences are found in most carcinomas originating from the uterine cervix. HPV E6 and E7 oncogenes have been shown to cooperate with ras oncogenes to fully transform human epithelial cells. We investigated the effect of the Ha-ras oncogene on the transcriptional activity of HPV-18 and found that it induced the transc...

High-risk-type human papillomavirus DNA sequences are found in a high percentage of carcinomas from the uterine-cervix, with the viral E1-E2 gene region usually disrupted and the E6 and E7 oncoproteins consistently expressed. The E2 protein is known to repress early transcription from genital HPV promoters having a proximal E2 binding site (E2BS) c...

The physical state of the human papillomavirus (HPV) genome is usually different in malignant lesions of the skin, in which it is generally found in episomal form, and genital mucosa, in which it is frequently integrated with disruption of the E2 gene. Using chimeric or natural HPV promoters in the presence of the bovine papillomavirus type 1 E2 ge...