Inbreeding and Gallbladder Cancer Risk: Homozygosity Associations Adjusted for Indigenous American Ancestry, BMI, and Genetic Risk of Gallstone Disease.

Latin Americans have a rich genetic make-up that translates into heterogeneous fractions of the autosomal genome in runs of homozygosity (F) and heterogeneous types and proportions of indigenous American ancestry. While autozygosity has been linked to several human diseases, very little is known about the relationship between inbreeding, genetic ancestry, and cancer risk in Latin Americans. Chile has one of the highest incidences of gallbladder cancer (GBC) in the world, and we investigated the association between inbreeding, GBC, gallstone disease (GSD), and body mass index (BMI) in 4029 genetically admixed Chileans.

Gallbladder Cancer Risk and Indigenous South American Mapuche Ancestry: Instrumental Variable Analysis Using Ancestry-Informative Markers.

A strong association between the proportion of indigenous South American Mapuche ancestry and the risk of gallbladder cancer (GBC) has been reported in observational studies. Chileans show the highest incidence of GBC worldwide, and the Mapuche are the largest indigenous people in Chile. We set out to assess the confounding-free effect of the individual proportion of Mapuche ancestry on GBC risk and to investigate the mediating effects of gallstone disease and body mass index (BMI) on this association.

Development and internal validation of a multifactorial risk prediction model for gallbladder cancer in a high-incidence country.

Since 2006, Chile has been implementing a gallbladder cancer (GBC) prevention program based on prophylactic cholecystectomy for gallstone patients aged 35 to 49 years. The effectiveness of this prevention program has not yet been comprehensively evaluated. We conducted a retrospective study of 473 Chilean GBC patients and 2137 population-based controls to develop and internally validate three GBC risk prediction models.

Identification of Circulating lncRNAs Associated with Gallbladder Cancer Risk by Tissue-Based Preselection, Cis-eQTL Validation, and Analysis of Association with Genotype-Based Expression.

Long noncoding RNAs (lncRNAs) play key roles in cell processes and are good candidates for cancer risk prediction. Few studies have investigated the association between individual genotypes and lncRNA expression. Here we integrate three separate datasets with information on lncRNA expression only, both lncRNA expression and genotype, and genotype information only to identify circulating lncRNAs associated with the risk of gallbladder cancer () using robust linear and logistic regression techniques.

Validation of an NGS Panel Designed for Detection of Actionable Mutations in Tumors Common in Latin America.

Next-generation sequencing (NGS) is progressively being used in clinical practice. However, several barriers preclude using this technology for precision oncology in most Latin American countries. To overcome some of these barriers, we have designed a 25-gene panel that contains predictive biomarkers for most current and near-future available therapies in Chile and Latin America.

Epigenome-Wide Analysis of Methylation Changes in the Sequence of Gallstone Disease, Dysplasia, and Gallbladder Cancer.

Background And Aims: Gallbladder cancer (GBC) is a highly aggressive malignancy of the biliary tract. Most cases of GBC are diagnosed in low-income and middle-income countries, and research into this disease has long been limited. In this study we therefore investigate the epigenetic changes along the model of GBC carcinogenesis represented by the sequence gallstone disease → dysplasia → GBC in Chile, the country with the highest incidence of GBC worldwide.

Gallstones, Body Mass Index, C-Reactive Protein, and Gallbladder Cancer: Mendelian Randomization Analysis of Chilean and European Genotype Data.

Background And Aims: Gallbladder cancer (GBC) is a neglected disease with substantial geographical variability: Chile shows the highest incidence worldwide, while GBC is relatively rare in Europe. Here, we investigate the causal effects of risk factors considered in current GBC prevention programs as well as C-reactive protein (CRP) level as a marker of chronic inflammation.

Approach And Results: We applied two-sample Mendelian randomization (MR) using publicly available data and our own data from a retrospective Chilean and a prospective European study.

ABCB1/4 gallbladder cancer risk variants identified in India also show strong effects in Chileans.

Background: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence.

Methods: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication.

[Porphyria cutanea tarda. Case report].

Porphyria cutanea tarda (PCT) is the most common type of porphyria: it is characterized by blistering lesions, erosions and crusts on the back of the hands, associated with photosensitivity and facial hypertrichosis. It is produced by acquired or hereditary deficiency of the enzyme UROD, fifth enzyme in the chain of production of the Heme group. This causes accumulation of porphyrins in the liver, which are subsequently mobilized to the skin, where lesions are generated by photosensitivity.

Expression of Peripheral Node Addressins by Plasmacytic Plaque of Children, APACHE, TRAPP, and Primary Cutaneous Angioplasmacellular Hyperplasia.

High-endothelial venules are a common feature of 3 types of cutaneous pseudolymphomas: pretibial lymphoplasmacytic plaque (PLP) of children, acral pseudolymphomatous angiokeratoma of children (APACHE), and T-cell rich angiomatoid polypoid pseudolymphoma (TRAPP). In addition, primary cutaneous angioplasmacellular hyperplasia (PCAH) overlaps with these other 3 conditions. We intend to study the expression of peripheral node addressins in PLP, APACHE, TRAPP, and PCAH.

[Morphea or juvenile localised scleroderma: Case report].

Introduction: Morphea or juvenile localised scleroderma (JLS) is an autoimmune, inflammatory, chronic, slowly progressive connective tissue disease of unknown cause that preferably affects skin and underlying tissues.

Objective: To report a case of Juvenil Localised scleroderma in an 8-year old girl, contributing to an early diagnosis and treatment.

Clinical Case: The case is presented of an 8 year-old girl who presented with indurated hypopigmented plaques, of linear distribution in the right upper extremity of two years onset, together with papery texture hyperpigmented indurated plaques with whitish areas of thinned skin in right lower extremity, and leg and ankle swelling.

Somatic Mutations of PI3K in Early and Advanced Gallbladder Cancer: Additional Options for an Orphan Cancer.

Gallbladder cancer (GBC) is the second-leading cause of death from malignant tumors in Chilean women. The phosphatidylinositol 3-kinase (PI3K) pathway is involved in proliferation, cell survival, and growth. We investigated mutations in exons 9 and 20 of the PI3K gene in GBC.

Inactivation of tumor suppressor gene pten in early and advanced gallbladder cancer.

Background: PTEN is a tumor suppressor gene that regulates the PTEN/PI3k/AKT/mTOR pathway, which is frequently altered in human cancers including gallbladder cancer (GBC). To determine the frequency of PTEN expression in GBC and to establish its relation to clinical and morphological parameters and survival in GBC.

Methods: The immunohistochemical expression of PTEN was studied in 108 GBC.

Overexpression of the HER2/neu Gene: A New Therapeutic Possibility for Patients With Advanced Gallbladder Cancer.

Background: The HER2/neu gene is a proto-oncogene that can predict the response to treatment with trastuzumab, pertuzumab, and lapatinib. This study was conducted to determine the frequency of HER2/neu overexpression and to identify a subgroup of patients with gallbladder cancer who would benefit from targeted therapy.

Methods: Patients with gallbladder cancer (n = 187; 165 women and 22 men) with a recorded follow-up of at least 5 years were included, along with control subjects (n = 75).

[Quality of DNA from archival pathological samples of gallbladder cancer].

Background: The quality of the archival samples stored at pathology services could be a limiting factor for molecular biology studies.

Aim: To determine the quality of DNA extracted from gallbladder cancer samples at different institutions.

Material And Methods: One hundred ninety four samples coming from five medical centers in Chile, were analyzed.

[HER2 gene amplification and overexpression in advanced gastric cancer].

Background: Overexpression/amplification of the HER2 gene in advanced gastric cancer is a predictor of response to adjuvant therapy with monoclonal antibodies.

Aim: To determine the frequency of HER2 gene overexpression and amplification in advanced gastric cancer.

Material And Methods: One hundred nine advanced gastric cancer biopsy specimens, from 76 men and 33 women aged 67 ± 14 and 62 ± 12 years respectively, were selected.

[Concomitant presence of a gastric adenocarcinoma and gastrointestinal stromal tumor: report of one case].

The concomitant presence of a primary gastric adenocarcinoma and a gastrointestinal stromal tumor in the stomach is uncommon. We report a 68-year-old male with an advanced gastric adenocarcinoma. During gastrectomy, a nodular intramural lesion was found.