Willingness toward post-mortem body donation to science at a Mexican university: an exploratory survey.

BACKGROUND: Voluntary post-mortem donation to science (PDS) is the most appropriate source for body dissection in medical education and training, and highly useful for biomedical research. In Mexico, unclaimed bodies are no longer a legal source, but PDS is legally possible, although scarcely facilitated, and mostly ignored by the general population. Therefore, we aimed to evaluate the attitude and willingness for PDS and to identify a sociodemographic profile of people with willingness toward PDS. METHODS: A validated on-line survey was distributed by the convenience method via the social networks of a Catholicism-inspired, private university in northern Mexico. Frequency analyses of all variables and coded free comments were complemented with association studies. RESULTS: Although the responder cohort (n = 143) was too small and biased to be representative of the university community (n = 13,500), willingness to post-mortem organ donation was 90.7% and to PDS 70.7%. In this cohort, PDS willingness had the strongest association with mature age (> 40 years old; P, 0.0008). Among young adults, willingness to PDS was the lowest among volunteers from technical and business schools and the highest among those from the social sciences (P, 0.009). Respondents from the social sciences were also the most consistent between attitude and behavior with respect to organ donation. A free comment option revealed respondents were interested in the unusual taboo topic. CONCLUSIONS: A small, but sufficiently large proportion expressed willingness toward PDS. In our university cohort, which was biased in higher education and altruism, mature age and social interest were associated with PDS willingness.

Psychiatric polygenic risk as a predictor of COVID-19 risk and severity: insight into the genetic overlap between schizophrenia and COVID-19.

Despite the high contagion and mortality rates that have accompanied the coronavirus disease-19 (COVID-19) pandemic, the clinical presentation of the syndrome varies greatly from one individual to another. Potential host factors that accompany greater risk from COVID-19 have been sought and schizophrenia (SCZ) patients seem to present more severe COVID-19 than control counterparts, with certain gene expression similarities between psychiatric and COVID-19 patients reported. We used summary statistics from the last SCZ, bipolar disorder (BD), and depression (DEP) meta-analyses available on the Psychiatric Genomics Consortium webpage to calculate polygenic risk scores (PRSs) for a target sample of 11,977 COVID-19 cases and 5943 subjects with unknown COVID-19 status. Linkage disequilibrium score (LDSC) regression analysis was performed when positive associations were obtained from the PRS analysis. The SCZ PRS was a significant predictor in the case/control, symptomatic/asymptomatic, and hospitalization/no hospitalization analyses in the total and female samples; and of symptomatic/asymptomatic status in men. No significant associations were found for the BD or DEP PRS or in the LDSC regression analysis. SNP-based genetic risk for SCZ, but not for BD or DEP, may be associated with higher risk of SARS-CoV-2 infection and COVID-19 severity, especially among women; however, predictive accuracy barely exceeded chance level. We believe that the inclusion of sexual loci and rare variations in the analysis of genomic overlap between SCZ and COVID-19 will help to elucidate the genetic commonalities between these conditions.

Gravedad de COVID-19 atribuible a obesidad según IMC y CUN-BAE / Severity of COVID-19 attributable to obesity according to BMI and CUN-BAE

Introducción La obesidad es considerada un factor de riesgo en casos graves de la COVID-19, habiendo sido analizada mediante el índice de masa corporal (IMC), estimador que no correlaciona adecuadamente con el porcentaje de grasa corporal (GC). El objetivo de este estudio ha sido analizar la fracción atribuible poblacional a la GC en formas graves de COVID-19 atendiendo al IMC y al CUN-BAE. Material y métodos Estudio multicéntrico observacional de prevalencia. Se recogió información sociodemográfica, antecedentes personales, IMC y CUN-BAE, de casos positivos SARS-CoV-2, de las provincias de León y La Rioja. Mediante modelos de regresión logística se calcularon odds ratio con sus respectivos intervalos de confianza del 95% ajustando por edad y antecedentes personales, así como la fracción atribuible poblacional a la GC. Resultados Participaron 785 pacientes, 123 (15,7%) fueron graves. Se detectaron como factores de riesgo la edad, la obesidad (tanto por IMC como por CUN-BAE) y los antecedentes personales. Un 51,6% de casos graves podrían ser atribuidos a un exceso de IMC y un 61,4% a exceso de GC estimada según CUN-BAE, observándose una mayor infraestimación del riesgo en mujeres. Conclusiones El exceso de GC es un factor de riesgo para formas graves de la COVID-19 junto con la edad avanzada y la presencia de enfermedades cardiovasculares, respiratorias crónicas u oncohematológicas. El IMC infraestima el riesgo, especialmente en mujeres, siendo el CUN-BAE el predictor seleccionado por su mejor estimación del porcentaje de GC (AU)

Introduction Obesity is considered a risk factor in severe cases of COVID-19, which has been analysed using body mass index (BMI), an estimator that does not correlate adequately with body fat (BF) percentage. The aim of this study was to analyse the population attributable fraction to BF in severe forms of COVID-19 based on BMI and CUN-BAE. Material and methods Multicentre observational prevalence study. Sociodemographic information, personal history, BMI and CUN-BAE were collected in SARS-CoV-2 positive cases from the provinces of León and La Rioja. Logistic regression models were used to calculate odds ratios with their respective 95% confidence intervals adjusting for age and personal history, as well as the population attributable fraction to BF. Results Seven hundred eighty-five patients participated, 123 (15.7%) were severe. Age, obesity (both by BMI and CUN-BAE) and personal history were detected as risk factors. 51.6% of severe cases could be attributed to excess BMI and 61.4% to excess BF estimated according to CUN-BAE, with a higher underestimation of risk in women. Conclusions Excess BF is a risk factor for severe forms of COVID-19 together with advanced age and the presence of cardiovascular, chronic respiratory or oncohematological diseases. BMI underestimates the risk especially in women, being CUN-BAE the predictor selected for its better estimation of the percentage of BF (AU)

[Severity of COVID-19 attributable to obesity according to BMI and CUN-BAE]. / Gravedad de COVID-19 atribuible a obesidad según IMC y CUN-BAE.

INTRODUCTION: Obesity is considered a risk factor in severe cases of COVID-19, which has been analysed using body mass index (BMI), an estimator that does not correlate adequately with body fat (BF) percentage. The aim of this study was to analyse the population attributable fraction to BF in severe forms of COVID-19 based on BMI and CUN-BAE. MATERIAL AND METHODS: Multicentre observational prevalence study. Sociodemographic information, personal history, BMI and CUN-BAE were collected in SARS-CoV-2 positive cases from the provinces of León and La Rioja. Logistic regression models were used to calculate odds ratios with their respective 95% confidence intervals adjusting for age and personal history, as well as the population attributable fraction to BF. RESULTS: Seven hundred eighty-five patients participated, 123 (15.7%) were severe. Age, obesity (both by BMI and CUN-BAE) and personal history were detected as risk factors. 51.6% of severe cases could be attributed to excess BMI and 61.4% to excess BF estimated according to CUN-BAE, with a higher underestimation of risk in women. CONCLUSIONS: Excess BF is a risk factor for severe forms of COVID-19 together with advanced age and the presence of cardiovascular, chronic respiratory or oncohematological diseases. BMI underestimates the risk especially in women, being CUN-BAE the predictor selected for its better estimation of the percentage of BF.

Case report: Disease phenotype associated with simultaneous biallelic mutations in ABCA4 and USH2A due to uniparental disomy of chromosome 1.

Inherited retinal diseases (IRDs) represent a spectrum of clinically and genetically heterogeneous disorders. Our study describes an IRD patient carrying ABCA4 and USH2A pathogenic biallelic mutations as a result of paternal uniparental disomy (UPD) in chromosome 1. The proband is a 9-year-old girl born from non-consanguineous parents. Both parents were asymptomatic and denied family history of ocular disease. Clinical history and ophthalmologic examination of the proband were consistent with Stargardt disease. Whispered voice testing disclosed moderate hearing loss. Next-generation sequencing and Sanger sequencing identified pathogenic variants in ABCA4 (c.4926C>G and c.5044_5058del) and USH2A (c.2276G>T). All variants were present homozygously in DNA from the proband and heterozygously in DNA from the father. No variants were found in maternal DNA. Further analysis of single nucleotide polymorphisms confirmed paternal UPD of chromosome 1. This is the first known patient with confirmed UPD for two recessively mutated IRD genes. Our study expands on the genetic heterogeneity of IRDs and highlights the importance of UPD as a mechanism of autosomal recessive disease in non-consanguineous parents. Moreover, a long-term follow-up is essential for the identification of retinal features that may develop as a result of USH2A-related conditions.

Population structure and relatedness estimates in a Mexican sample.

Population stratification (PS) is a confounding factor in genome-wide association studies (GWASs) and also an interesting process itself. Latin American populations have mixed genetic ancestry, which may account for PS. We have analyzed the relatedness, by means of the identity-by-descent (IBD) estimations, in a sample of 1805 individuals and 1.006.703 autosomal mutations from a case-control study of colorectal cancer in Mexico. When using the recommended protocol for quality control assessment, 402 should have been removed due to relatedness. Our purpose was to analyze this value in the context of an admixed population. For that aim, we reanalyzed the sample using two software designed for admixed populations, obtaining estimates of 110 and 70 related individuals to remove. The results showed that the first estimation of relatedness was an effect of the higher Native American contribution in part of the data samples, being a confounding factor for IBD estimations. We conclude in the importance of considering PS and genetic ancestry in order to avoid spurious results, not only in GWAS but also in relatedness analysis.

Exome sequencing reveals three homozygous missense variants in SNRPA in two sisters with syndromic intellectual disability.

Splicing-related gene mutations might affect the expression of a single gene or multiple genes and cause clinically heterogeneous diseases. With the advent of next-generation sequencing, several splicing gene mutations have been exposed, yet most major spliceosome genes have no reports of germline mutations and therefore, their effects are largely unknown. We describe the previously unreported concurrence of intellectual disability, short stature, poor speech, and minor craniofacial and hand anomalies in 2 female siblings with 3 homozygous missense variants in SNRPA (a component of the U1 small nuclear ribonucleoprotein complex) characterized by homozygosity mapping and whole exome sequencing. Combined, c.97A>G, c.98T>C, and c.100T>A, in exon 2 of SNRPA lead to p.Ile33Ala and p.Phe34Ile exchanges, which were predicted in silico to be deleterious. Although both patients exhibited some clinical features seen in other spliceosomal disorders, their complete clinical phenotype appears to be rather uncommon, a finding that may further support the notion that mutations in components of the major spliceosome do not strictly lead to the same syndromes/phenotypes.

MRPL53, a New Candidate Gene for Orofacial Clefting, Identified Using an eQTL Approach.

A valuable approach to understand how individual and population genetic differences can predispose to disease is to assess the impact of genetic variants on cellular functions (e.g., gene expression) of cell and tissue types related to pathological states. To understand the genetic basis of nonsyndromic cleft lip with or without cleft palate (NSCL/P) susceptibility, a complex and highly prevalent congenital malformation, we searched for genetic variants with a regulatory role in a disease-related tissue, the lip muscle (orbicularis oris muscle [OOM]), of affected individuals. From 46 OOM samples, which are frequently discarded during routine corrective surgeries on patients with orofacial clefts, we derived mesenchymal stem cells and correlated the individual genetic variants with gene expression from these cultured cells. Through this strategy, we detected significant cis-eQTLs (i.e., DNA variants affecting gene expression) and selected a few candidates to conduct an association study in a large Brazilian cohort (624 patients and 668 controls). This resulted in the discovery of a novel susceptibility locus for NSCL/P, rs1063588, the best eQTL for the MRPL53 gene, where evidence for association was mostly driven by the Native American ancestry component of our Brazilian sample. MRPL53 (2p13.1) encodes a 39S protein subunit of mitochondrial ribosomes and interacts with MYC, a transcription factor required for normal facial morphogenesis. Our study illustrates not only the importance of sampling admixed populations but also the relevance of measuring the functional effects of genetic variants over gene expression to dissect the complexity of disease phenotypes.

Crisis drepanocítica y tratamiento del dolor / Sickle cell crisis and treatment of pain

La drepanocitosis incluye un grupo de desórdenes genéticamente heredados en los que a baja saturación de oxígeno ocurre la agregación de polímeros rígidos de hemoglobina S desoxigenada, otorgando forma de hoz al hematíe y dañando el endotelio vascular por medio de múltiples mecanismos, obstruyendo concomitantemente la microcirculación y produciendo una estimulación de nociceptores. Los pacientes con drepanocitosis pueden presentar múltiples tipos de dolor dependiendo de las estructuras lesionadas, siendo el de tipo músculo-esquelético el más frecuente. La base del manejo del dolor es el reconocimiento y la evaluación de la severidad, ya que de esta dependerá la prescripción del tratamiento analgésico. Las crisis vasooclusivas son la manifestación más característica de esta enfermedad. Una vez instaurado el dolor, el manejo inicial debe enfocarse en proveer control rápido del mismo, garantizándose dosis terapéuticas de los fármacos, y en la detección de complicaciones. Debe evitarse el uso no indicado de las terapias y el tratamiento infraterapéutico, acompañado de un seguimiento cuidadoso, prevención y tratamiento de los efectos adversos. El tratamiento del dolor crónico se hace de forma multidisciplinaria, considerando estrategias no farmacológicas (AU)

Drepanocytosis includes a group of genetically inherited disorders in which low oxygen saturation rigid polymers aggregation deoxygenated hemoglobin S occurs, giving the red cell sickling and damaging the vascular endothelium through multiple mechanisms, and concomitantly blocking microcirculation producing a stimulation of nociceptors. Patients with sickle cell disease may have multiple types of pain depending on the injured structures, being the most common musculoskeletal type. The basis of pain management is the recognition and assessment of severity, since this will depend prescription analgesic treatment. The vaso-occlusive crises are the most characteristic manifestation of this disease. Once established pain, initial management should focus on providing rapid control of it, ensuring therapeutic doses of drugs, and the detection of complications. The not indicated therapies, accompanied by careful monitoring, prevention and treatment of adverse effects subtherapeutic use and treatment should be avoided. We report a 14 year old, of African origin, diagnosed with drepanocytosis and alpha thalassemia heterozygous with acute severe pain in lower limbs. The treatment of chronic pain is a multidisciplinary manner, considering nonpharmacologic strategies (AU)

Strong association of variants around FOXE1 and orofacial clefting.

Nonsyndromic orofacial clefting (nsOFC) is a common, complex congenital disorder. The most frequent forms are nonsyndromic cleft lip with or without cleft palate (nsCL/P) and nonsyndromic cleft palate only (nsCPO). Although they are generally considered distinct entities, a recent study has implicated a region around the FOXE1 gene in both nsCL/P and nsCPO. To investigate this hypothesis, we analyzed the 2 most strongly associated markers (rs3758249 and rs4460498) in 2 independent samples of differing ethnicities: Central European (949 nsCL/P cases, 155 nsCPO cases, 1163 controls) and Mayan Mesoamerican (156 nsCL/P cases, 10 nsCPO cases, 338 controls). While highly significant associations for both single-nucleotide polymorphisms were obtained in nsCL/P (rs4460498: p Europe = 6.50 × 10(-06), p Mayan = .0151; rs3758249: p Europe = 2.41 × 10(-05), p Mayan = .0299), no association was found in nsCPO (p > .05). Genotyping of rs4460498 in 472 independent European trios revealed significant associations for nsCL/P (p = .016) and nsCPO (p = .043). A meta-analysis of all data revealed a genomewide significant result for nsCL/P (p = 1.31 × 10(-08)), which became more significant when nsCPO cases were added (p nsOFC = 1.56 × 10(-09)). These results strongly support the FOXE1 locus as a risk factor for nsOFC. With the data of the initial study, there is now considerable evidence that this locus is the first conclusive risk factor shared between nsCL/P and nsCPO.

Positive association between vascular endothelial growth factor (VEGF) -2578 C/A variant and prostate cancer.

BACKGROUND: Vascular endothelial growth factor (VEGF) gene is an important angiogenesis regulator related to cancer development and progression. We evaluated the association between -2578 C/A (rs699947) VEGF polymorphism and PCa in Mexican subjects, to contribute to knowledge of VEGF role in genetic epidemiology of prostate cancer (PCa). OBJECTIVE: The aim of this study was to evaluate the association between -2578 C/A VEGF variant and PCa in Mexican population. METHODS: A total of 249 men (77 PCa cases and 172 controls) from the Northwestern region of Mexico were screened for the -2578 C/A VEGF variant. The polymorphism was determined by polymerase chain reaction-based restriction analysis. RESULTS: Genotype frequencies for C/C, C/A, and A/A, were 0.48, 0.49, 0.03 for cases and 0.41, 0.45, 0.14 for controls respectively. Genotype A/A of -2578 VEGF variant reduces the risk of PCa in an 84% among studied population (Odds Ratio 0.16; 95% CI: 0.04-0.71, P=0.007). C/C carriers showed an increased PCa risk of 6.1 times among the study population. CONCLUSIONS: Inheritance of -2578 A/A genotype of VEGF gene may modify PCa susceptibility risk in Mexican population.

Delineation of a de novo 7q21.3q31.1 Deletion by CGH-SNP Arrays in a Girl with Multiple Congenital Anomalies Including Severe Glaucoma.

In this study, we present a female patient with a constitutional de novo deletion in 7q21.3q31.1 as determined by G-banding and CGH-SNP arrays. She exhibited, among other features, psychomotor retardation, congenital severe bilateral glaucoma, a cleft palate, and heart defect. Microarray assay disclosed a deleted 12.5-Mb region roughly 88 kb downstream the ectrodactyly critical region; thus, the patient's final karyotype was 46,XX.arr 7q21.3q31.1(96,742,140-109,246,085)×1 dn. This girl represents the fourth patient described so far with congenital glaucoma and a deletion encompassing or overlapping the 7q21.3q31.1 region, and confirms the presence of a locus or loci related to such a clinical feature. According to our results, the proneness to ocular defects secondary to 7q intermediate deletions could be caused by co-deletion of TAC1, HBP1, and a small cluster of cytochrome P450 genes (subfamily 3A). This conclusion is supported by their functional roles and expression locations as well as because TAC1 is related to the functional pathway of the MYOC gene whose mutations are linked to glaucoma. Moreover, given that this girl is clinically reminiscent of several phenotypes related to diverse deletions within 7q21q32, our results and observations offer a general overview of the gene content of deletions/phenotypes overlapping 7q21.3q31.1 and confirm that loci distal to DLX genes including the CUX1 gene and potential regulatory elements downstream from DLX5 are unrelated to ectrodactyly.

Intraprostatic distribution and long-term follow-up after AdV-tk immunotherapy as neoadjuvant to surgery in patients with prostate cancer.

A phase I-II study to evaluate gene-mediated cytotoxic immunotherapy in newly diagnosed prostate cancer before radical prostatectomy was conducted in Monterrey, Mexico. First, to investigate delivery of adenovirus to the prostate, fluorescently labeled vector was injected into fresh prostatectomy specimens and distribution was visually analyzed. The optimal volume and site instillation was then used for transrectal ultrasound guided intraprostatic injection in 10 patients with adenocarcinoma scheduled for radical prostatectomy. Each received two apical and two basal 0.5 ml injections of AdV-tk for a total of 1 × 10(11) vp followed by 14 days of prodrug. Nine patients continued to tumor resection: six high risk, one intermediate and two low risk. In vivo vector distribution was analyzed from the resected tissue of four patients. Patients were monitored for tumor progression and acute and long-term safety. For vector delivery, two apical and two basal injections of 0.5 ml led to optimal organ-wide distribution ex vivo and in vivo. Cytotoxicity was evidenced by transient rise in PSA and tumor histology. There were no significant adverse events deemed related to the treatment and no late toxicities after median follow-up of 11.3 years. All six high-risk patients had positive surgical margins and one had seminal vesicle involvement. Despite slow PSA rise post surgery in three of these patients, none developed metastases. The intermediate- and low-risk patients had complete resections and none have progressed. In conclusion, in vivo transrectal ultrasound guided instillation of an adenoviral vector into four sites in the prostate was practical as an outpatient procedure, well tolerated and led to distribution throughout the intraprostatic tumor mass. AdV-tk demonstrated no significant acute or late toxicities. Trends in PSA and disease progression conveyed the possibility of a sustained immune response against residual disease.

A de novo sSMC(22) Characterized by High-Resolution Arrays in a Girl with Cat-Eye Syndrome without Coloboma.

Cat-eye syndrome (CES) results from trisomy or tetrasomy of proximal 22q originated by a small supernumerary marker chromosome (sSMC). Two critical regions for the major clinical features of CES (CESCRs) have been suggested; however, CES clinical presentation often does not correlate with the sSMC genetic content. We report here a CES girl without coloboma and carrier of a de novo type I sSMC(22) as determined by G- and C-banding, NOR staining and microarrays. This sSMC included 6 distal genes outside the original CESCR and led to a tetrasomy for 22q11.1-22q11.21. The patient's final karyotype was 47,XX,+psu dic(22)(q11.21).arr 22q11.1q11.21(15,250,000-17,035,860)×4 dn. The amplified region outside of CESCR included some genes that may be related to neurologic, heart and renal abnormalities. Conversely, even though the amplification included the CECR2 gene, a major candidate for eye features, there was no coloboma in the patient. The genetic delineation of the present sSMC further strengthens that the CES clinical presentation does not fit completely with the duplicated genetic content and that CES is actually a genomic disorder. Furthermore, since we observed no mosaicism, we believe that other mechanisms might be behind the variability of CES phenotypes as well, mainly those related with functional interactions among amplified genes.

Adenovirus-mediated thymidine kinase gene therapy for recurrent ovarian cancer: expression of coxsackie-adenovirus receptor and integrins alphavbeta3 and alphavbeta5.

OBJECTIVE: Ten patients with recurrent ovarian cancer received a combined treatment of optimal tumor debulking, adenovirus-mediated herpes simplex virus thymidine kinase gene therapy (GT), and systemic application of acyclovir or valacyclovir and topotecan. Biopsies were taken at the time of secondary debulking about 1 month after the application of GT and chemotherapy and were analyzed for expression of coxsackie-adenovirus receptor (CAR) and integrins alphavbeta3 and alphavbeta5 with respect to treatment response. METHODS: Treatment modalities and study design have been described recently. Immunohistochemistry was used to visualize expression of CAR and integrins alphavbeta3 and alphavbeta5 in tumor samples taken before and after application of GT. RESULTS: Before GT six of ten patients presented with CAR-positive and four with CAR-negative tumors. After GT all tumors showed CAR expression. Integrin alphavbeta3 was found in all tumors before and after GT. Expression of integrin alphavbeta5 was seen in eight of ten tumor samples before GT and in all samples after GT. CONCLUSION: Despite the importance of CAR and integrin expression for successful adenovirus internalization, other cell surface receptors might be involved in this process. It is too early to decide whether expressions of CAR and integrin alphavbeta3/alphavbeta5 on tumor cells are appropriate additional inclusion criteria for the enrollment of patients in GT trials. Further research is necessary to evaluate the effect of GT plus chemotherapy on CAR and integrin expression.

Histologic and immunohistochemical analysis of tissue response to adenovirus-mediated herpes simplex thymidine kinase gene therapy of ovarian cancer.

Herpes simplex virus (HSV) thymidine kinase (tk) gene incorporated into adenovirus was delivered intraperitoneally (ip) followed by an antiherpetic prodrug and topotecan in patients with recurrent epithelial ovarian cancer. Tissue response was evaluated. Ten patients underwent secondary debulking with subsequent delivery of ADV-HSV-tk therapy. Two patients each were treated at dose level 1 (2 x 10(10) vector particles = VP), 2 (2 x 10(11) VP), and 3 (2 x 10(12) VP); four patients were treated at dose level 4 (2 x 10(13) VP). Five patients underwent second-look surgery about one month after gene therapy (GT). Treatment response, presence of vector DNA, protein expression of steroid hormone receptors, p53, c-erbB2 and Ki67 protein were analyzed. At second-look, two out of five patients were tumor-free and none of their peritoneal biopsies showed vector DNA. After GT, the vital tumor mass was smaller, desmoplastic reaction had increased, and tumors were less differentiated with an increase of Ki67 expression. There was no change in expression of hormone receptors, p53, or c-erbB2. ADV-HSV-tk GT appears to eliminate cells with higher differentiation first and might induce fibrosis. Dedifferentiation might render residual cells more sensitive to chemotherapy secondary to their subsequent higher mitotic activity.

Adenovirus-mediated thymidine kinase gene therapy in combination with topotecan for patients with recurrent ovarian cancer: 2.5-year follow-up.

OBJECTIVE: Patients with recurrent ovarian cancer were treated intraperitoneally (ip) with a replication-deficient recombinant adenovirus (ADV) containing the herpes simplex virus thymidine kinase gene. Vector delivery was followed by intravenous administration of an antiherpetic prodrug and a topoisomerase I inhibitor. METHODS: Ten patients with stage IIIc epithelial ovarian cancer underwent secondary debulking to < or =0.5 cm residual tumor. Patients with normal ip flow received delivery of ip ADV. Two patients each were treated on dose level 1 (2 x 10(10) vector particles), dose level 2 (2 x 10(11)), and dose level 3 (2 x 10(12)); four patients were on dose level 4 (2 x 10(13)). Acyclovir and topotecan were started 24 h after vector delivery. Five patients underwent second-look surgery about 4 weeks after application of gene therapy (GT). RESULTS: At the time of the second-look surgery, two out of five patients were free of tumor. Four weeks after GT none of the peritoneal biopsies showed residual vector DNA. Patients pretreated with an average of three different chemotherapeutic drugs and two different chemotherapy regimens had a median overall survival (OS) of 18.5 months. Three patients are still alive 30, 30, and 31 months after GT. CONCLUSION: With the combination of secondary optimal debulking, GT, and topotecan, median OS was about one-third longer than in previously reported second-and third-line trials. Survival was comparable to that of patients of other studies with secondary cytoreductive surgery in combination with chemotherapy.

[677T mutation of the MTHFR gene in adenomas and colorectal cancer in a population sample from the Northeastern Mexico. Preliminary results]. / Mutación 677T del gen MTHFR en adenomas y cáncer colorrectal en una muestra de la población del noreste de México. Resultados preliminares.

INTRODUCTION: Adequate intake of folates has been associated to low prevalence of colon cancer. Methylenetetrahydrofolate reductase enzyme (MTHFR) plays an important role in folate metabolism. The role of the 677 mutation at the MTHFR gene in the risk for colorectal cancer remains controversial. A recent report established that this mutation has a high prevalence in the healthy Mexican population. AIMS: To analyze the prevalence of 677T MTHFR mutation in patients with colorectal cancer and controls without chronic gastrointestinal disorders. METHODS: Seventy-four colorectal cancer, 32 adenomas and 110 normal samples were analyzed. Patients and controls were matched for sex and age. For each sample, DNA isolation, PCR, and mutation detection by restriction enzyme digestion were performed to determine the allele at the 677 position in the MTHFR gene. RESULTS: Genotype 677C/677C was found in 18.7, 20.3, and 30.9% in adenomas, cancer lesions and controls, respectively. Frequencies of the 677C/677T genotype were 59.4, 56.7, and 47.3%, in adenomas, cancer lesions, and controls, respectively. Genotype 677T/677T was found in 21.9, 23.0, and 21.8% in adenomas, cancer lesions, and controls, respectively. The odds ratio between genotypes carrying the mutation (T/T and C/T) and normal genotype (CC) was 1.81 (IC 95% 0.97-3.3), chi 2 = 3.5, p = 0.06. CONCLUSION: Our results showed that persons who carry the 677T mutation at MTHFR locus have a tendency for an increased risk for colorectal cancer. This study supports the basic concept that low levels of folic acid contribute with the colorectal cancer pathogenesis. Our lack of statistic significance may be due to reduced sample size.