Findings and Challenges in Replacing Traditional Uterine Cervical Cancer Diagnosis with Molecular Tools in Private Gynecological Practice in Mexico.

We have been encouraging practicing gynecologists to adopt molecular diagnostics tests, PCR, and cancer biomarkers, as alternatives enabled by these platforms, to traditional Papanicolaou and colposcopy tests, respectively. An aliquot of liquid-based cytology was used for the molecular test [high-risk HPV types, (HR HPV)], another for the PAP test, and one more for p16/Ki67 dual-stain cytology. A total of 4499 laboratory samples were evaluated, and we found that 25.1% of low-grade samples and 47.9% of high-grade samples after PAP testing had a negative HR HPV-PCR result. In those cases, reported as Pap-negative, 22.1% had a positive HR HPV-PCR result. Dual staining with p16/Ki67 biomarkers in samples was positive for HR HPV, and 31.7% were also positive for these markers. Out of the PCR results that were positive for any of these HR HPV subtypes, n 68.3%, we did not find evidence for the presence of cancerous cells, highlighting the importance of performing dual staining with p16/Ki67 after PCR to avoid unnecessary colposcopies. The encountered challenges are a deep-rooted social reluctance in Mexico to abandon traditional Pap smears and the opinion of many specialists. Therefore, we still believe that colposcopy continues to be a preferred procedure over the dual-staining protocol.

SARS-CoV-2: Challenges in Reconverting Diagnostic Laboratories to Combat the Pandemic.

Coronavirus disease 2019 (COVID-19) was first detected in Mexico in February 2020. Even though health authorities did not perceive then the value of viral detection tests, we anticipated the demand for them. We set up to develop an expeditious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) molecular diagnostic service through the implementation of standardized protocols for biospecimen sampling, transportation, biobanking, preanalytical validation, and nucleic acids (NA) testing (NAT). Nasopharyngeal and oropharyngeal swabs collected in a special transportation medium were the biospecimens from which NAs were purified either manually or automatically. Viral RNA genome presence was determined using commercial SARS-CoV-2 detection kits (based on reverse transcription coupled with real-time PCR [RT-PCR]). Improvements in laboratory processing speed and reliability resulted from semi-automatizing laboratory processes and adopting a quality control/quality assurance system (QC/QA), respectively. NAs that were purified, either manually or automatically, were validated by preanalytical spectrophotometric characterization. Automated purification was less prone to contamination and reduced the processing time. The following six RT-PCR kits were evaluated for their convenience, specificity, sensitivity, time consumption, and required materials (in order, starting with the kit with the best results): RIDA gene and Viasure (tied), Vircell, LightMix, 1copy, and Logix Smart. Redesigning the laboratories' working areas, equipment, fluxes of personnel and material, and personnel skills, and overemphasizing biosafety safeguards were major challenges encountered in the middle of the sanitary crisis. Adopting a QC/QA system, utilizing automatization processes, and working closely with health authorities were key factors in our success. IMPORTANCE Rearranging our diagnostic laboratories to improve the fight against a new unexpected, unpredictable, and sudden public health threat demanded that we move quickly to redesign not only the laboratory processes but also the distribution of space, personnel activities, and fluxes of material coming in and out. We also had to work closely with governmental health authorities to gain their trust in our technical competence. Gaining the confidence of the clients, i.e., mainly individuals, the human resource departments of factories and corporations sending employees for testing, and medical institutions, and implementing as much automatization as possible of processes, in which only officially approved reagents (for extraction and analysis of NA) were used to generate opportune trustable testing results, were key factors. Our laboratories have gathered a considerable amount of experience and significant number of solutions, considering our geographic contexts alongside this continuously morphing pandemic, validating many techniques that might help other laboratories find a better and more precise workflow.

Pharmacogenetic Evaluation of Metformin and Sulphonylurea Response in Mexican Mestizos with Type 2 Diabetes.

BACKGROUND: In Mexico, approximately 25% of patients with type 2 diabetes (T2D) have adequate glycemic control. Polymorphisms in pharmacogenetic genes have been shown to have clinical consequences resulting in drug toxicity or therapeutic inefficacy. OBJECTIVE: The study aimed to evaluate the impact of variants in genes known to be involved in response to oral hypoglycemic drugs, such as CYP2C9, OCT, MATE, ABCA1 and C11orf65, in the Mexican Mestizo population of T2D patients. METHODS: In this study, 265 patients with T2D were enrolled from the Hospital Juárez de México, Mexico City. Genotyping was performed by TaqMan® assays. SNP-SNP interactions were analyzed using the multifactor dimensionality reduction (MDR) method. RESULTS: Carriers of the del allele of rs72552763 could achieve better glycemic control than noncarriers. There was a significant difference in plasma glucose and HbA1c levels among rs622342 genotypes. The results suggested an SNP-SNP interaction between rs72552763 and rs622342 OCT1 and rs12943590 MATE2. CONCLUSION: The interaction between rs72552763 and rs622342 in OCT1, and rs12943590 in MATE2 suggested an important role of these polymorphisms in metformin response in T2D Mexican Mestizo population.

Genetic variability of CYP2C9*2 and CYP2C9*3 in seven indigenous groups from Mexico.

AIM: CYP2C9 is one of the major drug metabolizing enzymes, however, little is known about polymorphisms in CYP2C9 gene and pharmacological implications in Mexican indigenous populations. Thus, frequencies of CYP2C9*2 and CYP2C9*3 alleles were evaluated in indigenous groups located in northwest (Cora), center (Mazahua and Teenek), south (Chatino and Mixteco) and southeast (Chontal and Maya) regions Mexico. MATERIALS & METHODS: Allelic discrimination was performed by real-time PCR. RESULTS: CYP2C9*2 allele was found only in Chontal and Maya groups, despite the low contribution of Caucasian component in these populations. CYP2C9*3 allele was present in all populations except in Mazahua, showing a wide genetic variability in the studied populations. Interestingly, we found significant differences between indigenous groups in CYP2C9*3 allele, even in groups located at the same region and belonging to the same linguistic family. CONCLUSION: These results contribute to laying the pharmacogenetic bases in Mexico, in addition to improving treatment, taking into account the genetic interethnic differences.