Zinc associated nanomaterials and their intervention in emerging respiratory viruses: Journey to the field of biomedicine and biomaterials

Respiratory viruses represent a severe public health risk worldwide, and the research contribution to tackle the current pandemic caused by the SARS-CoV-2 is one of the main targets among the scientific community. In this regard, experts from different fields have gathered to confront this catastrophic pandemic. This review illustrates how nanotechnology intervention could be valuable in solving this difficult situation, and the state of the art of Zn-based nanostructures are discussed in detail. For virus detection, learning from the experience of other respiratory viruses such as influenza, the potential use of Zn nanomaterials as suitable sensing platforms to recognize the S1 spike protein in SARS-CoV-2 are shown. Furthermore, a discussion about the antiviral mechanisms reported for ZnO nanostructures is included, which can help develop surface disinfectants and protective coatings. At the same time, the properties of Zn-based materials as supplements for reducing viral activity and the recovery of infected patients are illustrated. Within the scope of noble adjuvants to improve the immune response, the ZnO NPs properties as immunomodulators are explained, and potential prototypes of nanoengineered particles with metallic cations (like Zn2+) are suggested. Therefore, using Zn-associated nanomaterials from detection to disinfection, supplementation, and immunomodulation opens a wide area of opportunities to combat these emerging respiratory viruses. Finally, the attractive properties of these nanomaterials can be extrapolated to new clinical challenges.

Development of an alternative saliva test for diagnosis of SARS-CoV-2 using TRIzol: Adapting to countries with lower incomes looking for a large-scale detection program

The use of saliva for the diagnosis of SARS-CoV-2 has shown to be a good alternative to nasopharyngeal swabs (NPS), since it permits self-collection, avoids the exposure of healthy persons to infected patients, reduces waiting times, eliminates the need of personal protective equipment and is non-invasive. Yet current saliva testing is still expensive due to the need of specialized tubes containing buffers to stabilize the RNA of SARS-CoV-2 and inactivate the virus. These tubes are expensive and not always accessible in sufficient quantities. We now developed an alternative saliva testing method, using TRIzol for extraction, viral inactivation, and storage of SARS-CoV-2 RNA, combined with RT-qPCR, which was comparable in its performance to NPS. Paired saliva samples and NPS were taken from 15 asymptomatic healthcare workers and one patient with SARS-CoV-2. Further 13 patients with SARS-CoV-2 were only saliva-tested. All the tests were performed according to CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel. Saliva (4 mL) was taken in sterile 50 mL tubes, 1.5 mL TRIzol were added and mixed. Our results show that 5 μL of saliva RNA extracted with TRIzol allow for an adequate detection of the virus in patients positive for SARS-CoV-2 and was equally sensitive to NPS in TRIzol. We conclude that saliva testing using TRIzol is a recommendable method for diagnosis of SARS-CoV-2 since it has several advantages over currently used saliva tests: it can be done with normal sterile tubes, does not need cold-chain handling, is stable at room temperature, is non-invasive and less costly, making it more accessible for low-income countries. Cheaper saliva testing using TRIzol is especially relevant for low-income countries to optimize diagnosis and help define quarantine durations for families, healthcare workers, schools, and other public workplaces, thus decreasing infections and mortality caused by SARS-CoV-2.

National Clinical Practice Guidelines for the management of non-small cell lung cancer in early, locally advanced and metastatic stages. Extended version

OBJECTIVE

Lung cancer is one the leading causes of mortality worldwide. Symptomatic manifestations of the disease generally occur in the advanced-stage setting, and therefore an important number of patients have advanced or metastatic disease by the time they are diagnosed. This situation contributes to a poor prognosis in the treatment of lung cancer. Evidencebased clinical recommendations are of great value to support decision-making for daily practice, and thus improving health care quality and patient outcomes.

MATERIALS AND METHODS

This document was an initiative of the Mexican Society of Oncology (SMEO) in collaboration with Mexican Center of Clinical Excellence (Cenetec) according to Interna- tional Standards. Such standards included those described by the IOM, NICE, SIGN and GI-N. An interdisciplinary Guideline Development Group (GDG) was put together which included medical oncologists, surgical oncologistsc, radiation therapists, and methodologists with expertise in critical appraisal, sys- tematic reviews and clinical practice guidelines development.

RESULTS

62 clinical questions were agreed among members of the GDG. With the evidence identified from systematic reviews, the GDG developed clinical recommendations using a Modified Delphi Panel technique. Patients' representatives validated them.

CONCLUSIONS

These Clinical Practice Guideline aims to support the shared decision-making process for patients with different stages of non-small cell lung cancer. Our goal is to improve health-care quality on these patients.

DNA Repair Proteins as Therapeutic Targets in Ovarian Cancer

Epithelial ovarian cancer is a serious public health problem worldwide with the highest mortality rate of all gynecologic cancers. The current standard-of-care for the treatment of ovarian cancer is based on chemotherapy based on adjuvant cisplatin/carboplatin and taxane regimens that represent the first-line agents for patients with advanced disease. The DNA repair activity of cancer cells determines the efficacy of anticancer drugs. These features make DNA repair mechanisms a promising target for novel cancer treatments. In this context a better understanding of the DNA damage response caused by antitumor agents has provided the basis for the use of DNA repair inhibitors to improve the therapeutic use of DNA-damaging drugs. In this review, we will discuss the functions of DNA repair proteins and the advances in targeting DNA repair pathways with special emphasis in the inhibition of HRR and BER in ovarian cancer. We focused in the actual efforts in the development and clinical use of poly (ADPribose) polymerase (PARP) inhibitors for the intervention of BRCA1/BRCA2-deficient ovarian tumors. The clinical development of PARP inhibitors in ovarian cancer patients with germline BRCA1/2 mutations and sporadic high-grade serous ovarian cancer is ongoing. Some phase II and phase III trials have been completed with promising results for ovarian cancer patients.

HypoxamiRs Profiling Identify miR-765 as a Regulator of the Early Stages of Vasculogenic Mimicry in SKOV3 Ovarian Cancer Cells

Vasculogenic mimicry (VM) is a novel cancer hallmark in which malignant cells develop matrix-associated 3D tubular networks with a lumen under hypoxia to supply nutrients needed for tumor growth. Recent studies showed that microRNAs (miRNAs) may have a role in VM regulation. In this study, we examined the relevance of hypoxia-regulated miRNAs (hypoxamiRs) in the early stages of VM formation. Data showed that after 48 h hypoxia and 12 h incubation on matrigel SKOV3 ovarian cancer cells undergo the formation of matrix-associated intercellular connections referred hereafter as 3D channels-like structures, which arose previous to the apparition of canonical tubular structures representative of VM. Comprehensive profiling of 754 mature miRNAs at the onset of hypoxia-induced 3D channels-like structures showed that 11 hypoxamiRs were modulated (FC>1.5; p < 0.05) in SKOV3 cells (9 downregulated and 2 upregulated). Bioinformatic analysis of the set of regulated miRNAs showed that they might impact cellular pathways related with tumorigenesis. Moreover, overall survival analysis in a cohort of ovarian cancer patients (n = 485) indicated that low miR-765, miR-193b, miR-148a and high miR-138 levels were associated with worst patients outcome. In particular, miR-765 was severely downregulated after hypoxia (FC < 32.02; p < 0.05), and predicted to target a number of protein-encoding genes involved in angiogenesis and VM. Functional assays showed that ectopic restoration of miR-765 in SKOV3 cells resulted in a significant inhibition of hypoxia-induced 3D channels-like formation that was associated with a reduced number of branch points and patterned tubular-like structures. Mechanistic studies confirmed that miR-765 decreased the levels of VEGFA, AKT1 and SRC-α transducers and exerted a negative regulation of VEGFA by specific binding to its 3‘UTR. Finally, overall survival analysis of a cohort of ovarian cancer patients (n = 1435) indicates that high levels of VEGFA, AKT1 and SRC-α and low miR-765 expression were associated with worst patients outcome. In conclusion, here we reported a novel hypoxamiRs signature which constitutes a molecular guide for further clinical and functional studies on the early stages of VM. Our data also suggested that miR-765 coordinates the formation of 3D channels-like structures through modulation of VEGFA/AKT1/SRC-α axis in SKOV3 ovarian cancer cells.

MicroRNA-143 is Associated With Pathological Complete Response and Regulates Multiple Signaling Proteins in Breast Cancer

Almost 55% to 80% of patients with breast cancer have an unfavorable pathological complete response to chemotherapy. MicroRNAs are small noncoding RNAs involved in cancer progression; however, their utility as predictors of pathological complete response to neoadjuvant chemotherapy is unclear. Here, we investigated if miR-143 could discriminate between pathological complete response and no-polymerase chain reaction of patients with locally advanced triple negative breast cancer that have received a fluorouracil-cisplatin/paclitaxel-based neoadjuvant treatment. Data showed that miR-143 exhibited a significant low expression (P < .0006) in patients that achieved pathological complete response in comparison to nonresponder group. Receiver operating characteristic curve analysis suggested that miR-143 could be a good predictor of pathological complete response (area under curve = 0.849, P < .0006). Moreover, Kaplan-Meier analysis indicated that before neoadjuvant therapy low levels of miR-143 were associated to increased disease free survival. To gain insights into cellular functions of miR-143, we firstly showed that miR-143 was severely repressed in breast cancer cell lines and tumors in comparison to normal mammary cells and tissues. Ectopic restoration of miR-143 using RNA mimics inhibited both cell proliferation and migration and sensitized breast cancer cells to cisplatin therapy in vitro. To decipher the signaling networks regulated by miR-143, we used a high-throughput enzyme-linked immunosorbent assay-based phosphorylation antibody array. Phospho-proteomic profiling revealed that miR-143 coordinately reduced the protein levels and phosphorylation status of multiple oncoproteins involved in AKT, WNT/β-catenin, SAPK/JNK, FAK, and JAK/STAT signaling pathways. Moreover, low miR-143 and high GSK3-β, RAF1, paxillin, and p21CIP1 expression levels in a large cohort of patients with breast cancer were associated with worst outcome. In summary, miR-143 could be a potential predictor of response to neoadjuvant therapy and it may function as a divergent regulator of diverse signaling networks to suppress cell proliferation and migration in breast cancer.

Dietary Compounds as Epigenetic Modulating Agents in Cancer

Epigenetic mechanisms control gene expression during normal development and their aberrant regulation may lead to human diseases including cancer. Natural phytochemicals can largely modulate mammalian epigenome through regulation of mechanisms and proteins responsible for chromatin remodeling. Phytochemicals are mainly contained in fruits, seeds, and vegetables as well as in foods supplements. These compounds act as powerful cellular antioxidants and anti-carcinogens agents. Several dietary compounds such as catechins, curcumin, genistein, quercetin and resveratrol, among others, exhibit potent anti-tumor activities through the reversion of epigenetic alterations associated to oncogenes activation and inactivation of tumor suppressor genes. In this review, we summarized the actual knowledge about the role of dietary phytochemicals in the restoration of aberrant epigenetic alterations found in cancer cells with a particular focus on DNA methylation and histone modifications. Furthermore, we discussed the mechanisms by which these natural compounds modulate gene expression at epigenetic level and described their molecular targets in diverse types of cancer. Modulation of epigenetic activities by phytochemicals will allow the discovery of novel biomarkers for cancer prevention, and highlights its potential as an alternative therapeutic approach in cancer.

Abstract 4221: Association between SOX9 expression in Mexican patients with early colon cancer stage

Introduction. Colon cancer is the fourth leading cause of mortality worldwide. Between 30-40% of patients are diagnosed at early stage (I or II), sadly 20% will relapse. It is necessary to have a biomarker that identifies patients at high risk. SOX 9 is a transcription factor required for differentiation of different cells and is important for cell proliferation, senescence and lineage commitment. The exact role of SOX9 in carcinogenesis and cancer progression is controversial because could have oncogenic and tumor-suppressing functions. Reports show that strong levels of SOX 9 in colon cancer stage II are linked to low risk of relapse. Objective. The aim of this study was to investigate if the protein expression of SOX9 was associated with the stage, clinical characteristics and relapse of Mexican colon cancer patients. Methods. We obtained 97 samples embedded in paraffin. A pathologist blinded to the clinical information determined the immunoreactivity of SOX9 into 2 groups: low and high expression (by evaluating the percentage of positive nucleus and the tissue staining intensity). All statistical analyses were conducted with SPSS v.22 Statistics. Results. We include stage I (N= 34) and stage II (N=63) patients. The median follow-up period was 42 months. We found statistical difference between SOX9 expression and age (p=0.003), tumor localization (p=0.048) and stage (p&lt0.001) for whole patients group. Twelve patients (12.3%) relapsed, 7 (at locally level) and 5 with distant metastasis: liver (N=3) and retroperitoneal nodes (N=2), all had low SOX9 expression; one patient with local relapse had died (because of surgical complications). In the relapse group, we found a significant correlation between SOX9 expression and stage (p=0.038) but not with relapse free survival (RFS). Conclusion. We found interesting data even though this is a retrospective study with limitations. This study could not associated SOX9 and RFS, because there are few events. Nevertheless, we observe that 41% patients had a systemic relapse. In the other hand, the youngest patients (&lt40 y) and the right colon had the highest SOX9 expression. With this result, we have decided to increase the sample size before any assumption, and perform NGS to the five systemic relapses.

Citation Format: Erika Ruiz-Garcia, Tatiana Galicia, Edith Fernandez Figueroa, Saul Lino-Silva, Cesar Lopez-Camarillo, Laurence Marchat, German Calderillo, Juan Zinser, Abelardo Meneses-Garcia, Horacio Astudillo-de la Vega. Association between SOX9 expression in Mexican patients with early colon cancer stage [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4221.

Gastric cancer in Latin America

Every year, cancer affects more than one million Latin Americans. The increasing incidence of cancer could be secondary to an aging population, westernization of life style, and urbanization. LA has among the highest incidence rates of gastric cancer, compared to other countries. In this review, different studies on gastric cancer and its relation with risks factors, such as infections, diet and life styles typical of LA, besides the different molecular alterations of that specific population (mainly at a genetic polymorphism level) are analyzed. An exhaustive research was made in PubMed, MEDLINE and Embase of the most relevant studies conducted in the last 27 years (1990-2017) in LA.

Reduction in Hepatocyte Growth Factor Serum Levels is Associated with Improved Prognosis in Advanced Lung Adenocarcinoma Patients Treated with Afatinib: a Phase II Trial

BACKGROUND

C-met and its ligand, hepatocyte growth factor (HGF) have been associated with the resistance mechanism of EGFR-TKIs. HGF was evaluated as a clinical-marker of response in NSCLC patients treated with afatinib.

METHODS

Sixty-six patients with stage IIIB/IV lung adenocarcinoma and progression to any-line chemotherapy received afatinib 40 mg/day. Mutational EGFR and HER2 status were assessed by RT-PCR. HER2 amplification was evaluated by FISH. Serum HGF content was measured by ELISA before and 2 months after the start of treatment. HGF levels were assessed with the objective response rate (ORR), progression-free-survival (PFS), and overall survival (OS). This trial was registered on ClinicalTrials.gov: NCT01542437.

RESULTS

Fifty patients (75 %) were EGFR mutation positive. Response was achieved in 59 % of all patients and 78 % of EGFR mutated patients. Median PFS was 10 [95 % CI 6.8-13.1] and 14.5 months [10.9-18.9] for all and EGFR mutated patients, respectively. Median OS was 22.8 [17.5-28.1] and 32.4 months [18.3-46.6] for all and EGFR mutated patients, respectively. Patients with reduced serum HGF levels had improved ORR (75 % vs 44 %; p = 0.011), PFS (15.1 [2.9-27.3] vs 6.5 months [3.9-9.1]; p = 0.005) and OS (NR vs 14.5 months [7.8 - 21.3] p = 0.007). A reduction in serum HGF levels was an independent factor associated with longer PFS (HR 0.40; p = 0.021) and OS (HR 0.31; p = 0.006) in all and EGFR mutated patients.

CONCLUSIONS

A reduction in serum HGF levels was associated with improved outcomes in patients treated with afatinib. These results suggest HGF might have a role as a mechanism of resistance to EGFR-TKIs. HGF could represent a potential therapeutic target to prevent or reverse resistance particularly in EGFR mutated patients.

A microRNA signature associated with pathological complete response to novel neoadjuvant therapy regimen in triple-negative breast cancer

Neoadjuvant chemotherapy aims to improve the outcome of breast cancer patients, but only few would benefit from this treatment. Pathological complete response has been proposed as a surrogate marker for the prediction of long-term clinical benefits; however, 50%-85% patients have an unfavorable pathological complete response to chemotherapy. MicroRNAs are known biomarkers of breast cancer progression; nevertheless, their potential to identify patients with pathological complete response remains poorly understood. Here, we investigated whether a microRNA profile could be associated with pathological complete response in triple-negative breast cancer patients receiving 5-fluorouracil, adriamycin, cyclophosphamide-cisplatin/paclitaxel as a novel neoadjuvant chemotherapy. In the discovery cohort, the expression of 754 microRNAs was examined in tumors from 10 triple-negative breast cancer patients who achieved pathological complete response and 8 without pathological complete response using TaqMan Low-Density Arrays. Unsupervised hierarchical cluster analysis identified 11 microRNAs with significant differences between responder and no-responder patients (fold change ≥ 1.5; p < 0.05). The differential expression of miR-30a, miR-9-3p, miR-770, and miR-143-5p was validated in an independent group of 17 patients with or without pathological complete response. Moreover, Kaplan-Meier analysis showed that expression of these four microRNAs was associated with an increased disease-free survival. Gene ontology classification of predicted microRNA targets indicated that numerous genes are involved in pathways related to chemoresistance, such as vascular endothelial growth factor, focal adhesion kinase, WNT, ERbB, phosphoinositide 3-kinase, and AKT signaling. In summary, we identified a novel microRNA expression signature associated with pathological complete response in breast cancer. We propose that the four validated microRNAs could be used as molecular biomarkers of clinical response in triple-negative breast cancer patients with pathological complete response to neoadjuvant therapy.

Abstract 2728: Frequency and prognostic value of PI3KCA mutations in early stage of colorectal cancer in Mexican patients

Background: There are molecular associations between mutated profiles and microsatelital instability, both related with tumor growth and oncogenic development by activating tyrosine receptors families in colorectal cancer (CRC). It is known that exon 9 and exon 20 (H1047R) mutations in PIK3CA increased PI3K activity. Moreover, PIK3CA mutations are significantly associated with tumor recurrence and poor overall survival. The frequency of PIK3CA mutations in CCR occurs in 15-20%, being the catalytic subunit more frequently affected. The aim of our study was to investigate the frequencies and clinical implications of these genetic alterations in advanced CRC.

Methods: Retrospectively, we analyzed the initial paraffin embedded tissue block of 71 Mexican patients with CCR stage II. We evaluated mutations frequency of PIK3CA exon 9 (E542K, E545K) and exon 20 (H1047R) using qBiomarker Somatic Mutation PCR for real-time PCR-based. These methodology increases specificity, multiplex PCR and allelic discrimination. The data analysis was done using Ct values and Analysis Webportal.

Results: We found in our population a frequency of PIK3CA mutations of 26%. Of those, double mutants were present in 7% with a higher frequency for E545K/H1047R. Clinical implication that we found is that any active mutation of PIK3CA is associated to an increase of recurrence risk (HR 1.86;CI 95% =0.46-7.5), but most important is for E545K mutation (HR 4.17; CI 95% 0.85-20.39), meanwhile comparing no mutated with H1074R mutated samples there were no differences in HR (0.53 vs. 0.60, respectively).

Conclusions: We found a higher number of PI3KCA mutations that literature reports and that E545K mutation have a worst prognostic implication but we need to increase our sample looking for statistical significance results. Data from H1047R mutation raise de hypothesis that it could exist a compensatory mechanism related to structural interactions between both helicoidal and catalitic domains.

Citation Format: Erika Ruiz-Garcia, Alette Ortega, Antonio Bahena, Edith Fernandez, German Calderillo, Cesar Lopez Camarillo, Laurence Marchat, Jorge Guadarrama, Abelardo Meneses-Garcia, Horacio Astudillo-de la Vega. Frequency and prognostic value of PI3KCA mutations in early stage of colorectal cancer in Mexican patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2728. doi:10.1158/1538-7445.AM2017-2728

Abstract 1786: Predictive value of LRP8, KPNA2 and GDF15 expression to anthracycline/taxane based chemotherapy response in patients with locally advanced breast cancer

Background: Chemotherapy plays a major role in its treatment, though overtreatment is frequent since its choice is based on clinicopathological prognostic data. The identification and validation of new predictive profiles or markers continues to be relevant. New findings may contribute to achieve better results in this area, as well as to provide new targets of the pathways involved in chemoresistance. Karyopherin α2 (KPNA2), low density lipoprotein receptor-related protein 8 (LRP8) and growth and differentiation factor 15 (GDF15), are three candidate predictive biomarkers in breast cancer, previously identified on DNA microarrays reports.

Methods: Using tissue microarrays technology and immunohistochemistry, we compared the expression of these three markers between cases of breast cancer with response to chemotherapy (absence of recurrence), and those with failure (with recurrence). All patients received chemotherapy based on anthracyclines and taxanes. Potential confounding factors, as known recurrence and progression risk factors, were controlled for during the comparison.

Results: 20 out of 63 patients had tumor recurrence. Potential confounding factors were similar among cases with response and failure to chemotherapy. For KPNA2 no differences were found between cases with response or failure. LRP8 showed higher expression in cases with failure to chemotherapy (mean 7.22 vs 14.01%, p =0.025). In Cox multivariable regression analysis, which included potential confounding factors as covariates, only LRP8 remained as a significant predictive factor (HR 1.28, p=0.016). GDF15 showed no expression in our cases, nor in an external set of cases.

Conclusions: We demonstrated increased expression of LRP8 in breast cancer cases recurring after chemotherapy. KPNA2 and GDF 15 showed no predictive value for chemotherapy response in our study. LRP8 is a potential predictive marker worth of further investigation for its role in chemoresistance as well as for its potential validation.

Note: This abstract was not presented at the meeting.

Citation Format: Hector Maldonado-Mtz, Alonso-Luna Oscar, Ali Flores-Perez, Meneses-Garcia Abelardo, Erika B. Ruiz-Garcia, Cesar Lopez-Camarillo, Horacio Astudillo-de la Vega. Predictive value of LRP8, KPNA2 and GDF15 expression to anthracycline/taxane based chemotherapy response in patients with locally advanced breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1786. doi:10.1158/1538-7445.AM2017-1786

Frequency of BRAF V600E Mutation in the Mexican Population of Patients With Metastatic Melanoma

Purpose

The BRAF V600E mutation has been described in melanomas occurring in the Caucasian, European, and Asian populations. However, in the Mexican population, the status and clinical significance of BRAF mutation has not been researched on a large scale.

Methods

Consecutive BRAF-tested Mexican patients with metastatic melanoma (n = 127) were analyzed for mutations in exon 15 of the BRAF gene in genomic DNA by real-time polymerase chain reaction technology for amplification and detection. The results were correlated with the clinical-pathologic features and the prognosis of the patients.

Results

The frequency of somatic mutation V600E within the BRAF gene was 54.6% (43 of 127 patients). Nodular melanoma was the most prevalent subtype in our population, with BRAF mutations in 37.2% (16 of 55 patients). In contrast, superficial spread had a frequency of 18.6% BRAF mutation (eight of 24). Other clinicopathologic features were assessed to correlate with the mutation status.

Conclusion

This study searched for the most prevalent BRAF V600E mutation type in melanoma in a heterogeneous population from Mexico. Nodular melanoma was found to be the most prevalent in metastatic presentation and the presence of BRAF V600E mutation, perhaps related to the mixed ancestry; in the north, ancestry is predominantly European and in the south, it is predominantly Asian. The outcomes of the mutation correlations were similar to those found in other populations.

Search of the p.M918T Mutation in the RET Oncogene in Mexican Adult Patients with Medullary Thyroid Carcinoma

Inherited mutations in the RET proto-oncogene, which encodes a receptor tyrosine kinase, predispose individuals to the multiple endocrine neoplasia type 2 (MEN 2) cancer syndromes. The major component tumor of these syndromes is medullary thyroid carcinoma (MTC). To date, somatic mutations in RET have been identified in tumors from individuals with MEN 2 finding. RET M918T mutation is present in 95% of the MEN2B cases, and approximately 50% of sporadic MTCs harbor this mutation. We performed a mutational analysis in 17 cases of Medullary thyroid carcinoma, the somatic missense mutation at codon 918 of RET was found in 2 of the 17 MTCs, and one case presented MEN2 phenotype including MTC. The percentage of RET M918T mutation is similar in Mexican MTC patients to other series, although other mutations could be implicated in our population.

Dual targeting of ANGPT1 and TGFBR2 genes by miR-204 controls angiogenesis in breast cancer

Deregulated expression of microRNAs has been associated with angiogenesis. Studying the miRNome of locally advanced breast tumors we unsuspectedly found a dramatically repression of miR-204, a small non-coding RNA with no previous involvement in tumor angiogenesis. Downregulation of miR-204 was confirmed in an independent cohort of patients and breast cancer cell lines. Gain-of-function analysis indicates that ectopic expression of miR-204 impairs cell proliferation, anchorage-independent growth, migration, invasion, and the formation of 3D capillary networks in vitro. Likewise, in vivo vascularization and angiogenesis were suppressed by miR-204 in a nu/nu mice model. Genome-wide profiling of MDA-MB-231 cells expressing miR-204 revealed changes in the expression of hundred cancer-related genes. Of these, we focused on the study of pro-angiogenic ANGPT1 and TGFβR2. Functional analysis using luciferase reporter and rescue assays confirmed that ANGPT1 and TGFβR2 are novel effectors downstream of miR-204. Accordingly, an inverse correlation between miR-204 and ANGPT1/TGFβR2 expression was found in breast tumors. Knockdown of TGFβR2, but not ANGPT1, impairs cell proliferation and migration whereas inhibition of both genes inhibits angiogenesis. Taken altogether, our findings reveal a novel role for miR-204/ANGPT1/TGFβR2 axis in tumor angiogenesis. We propose that therapeutic manipulation of miR-204 levels may represent a promising approach in breast cancer.

Abstract 3173: Next generation sequencing (NGS) of dihydropyrimidine dehydrogenase (DPYD) gene in Mexican patients with gastrointestinal (GI) carcinomas

Background: Fluoropyrimidines (5-fluorouracil (5-FU), capecitabine and tegafur) are the mainstay chemotherapeutic drugs for gastrointestinal cancer. Patients with deficiency of dihydropyrimidine dehydrogenase enzyme (DPD), which interfere with the pyrimidine metabolism, could be at risk toxicity (mild, severe or lethal) because &gt;80% of the administered 5-FU is catabolized by DPD. Previously, our group studied DPYD single-nucleotide polymorphism (SNPs) by real-time PCR assay, in 72 Mexicans. We found that frequency of SNP 85T&gt;C and 85T&gt;T was similar as Oriental race (2-3%), but contrast with Caucasians (0.19%), meanwhile, for SNP 496A&gt;G which Caucasian prevalence was reported 0.8%, in our Mexican sample was very high (14%). Even though, none of our patients with toxicity grade 3-4, were positive to the SNP associated to higher toxicity (IVS14 + 1G&gt;A). Because of this heterogeneity, we decide to sequence the complete gen in our population.

Methods: We included prospectively, 19 patients of the GI Oncology Department of the National Cancer Institute of Mexico, who were treated with fluoropyrimidines. We follow them during the whole treatment. DNA was extracted from whole blood using the DNeasy blood and tissue kit (Qiagen Ltd, Crawley, UK). We use the AmpliSeq™ Designer for the full coverage of all 23 exons of DPYD gene; 25 μg of DNA was used for library construction (Ion Ampliseq Library kit 2.0), we follow the manufacturer's instructions for the target sequencing of DPYD gene with the Ion Torrent PGM platform. The data management was performed with the Ion Reporter Software of Thermo Fisher.

Results: We found that 89.5% of the patients had SNPs (c.85C&gt;T), 44.1% (c.1627A&gt;G) and 5.2% (c.496A&gt;G). Mean while SNPs: c.1896T&gt;C, c.451A&gt;G, c.771C&gt;T, c.2384G&gt;A, c.2605G&gt;A, c.1462A&gt;G, c.1422_1422delA were present in a lower frequencies. These results were associated to clinical toxicity (mucositis, neurotoxicity, hand foot syndrome, hematological toxicity and diarrhea grade &gt;2) but there wasn't any association (chi2 test). Not a single patient were positive for IVS14 + 1G&gt;A.

Conclusion: These are the first results using NGS for DPYD gene in Mexican people. We confirm that our population had a different molecular profile that Caucasians. We need to improve the sample size, to see if we could find an association between SNPs and clinical toxicity.

Citation Format: Erika Ruiz-Garcia, Alicia Lopez-Yanez, Alette Ortega, Jorge Guadarrama-Orozco, Gisela Hernandez-Luis, Fabiola De la Rosa, Abelardo Meneses-Garcia, Horacio Astudillo-de la Vega. Next generation sequencing (NGS) of dihydropyrimidine dehydrogenase (DPYD) gene in Mexican patients with gastrointestinal (GI) carcinomas. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3173.

Suppression of cell migration is promoted by miR-944 through targeting of SIAH1 and PTP4A1 in breast cancer cells

Background

Aberrant expression of microRNAs has been associated with migration of tumor cells. In this study, we aimed to investigate the biological significance of miR-944 whose function is unknown in breast cancer.

Methods

MiR-944 expression in breast cancer cells and tumors was evaluated by Taqman qRT-PCR assays. Transcriptional profiling of MDA-MB-231 cells expressing miR-944 was performed using DNA microarrays. Cell viability, migration and invasion were assessed by MTT, scratch/wound-healing and transwell chamber assays, respectively. The luciferase reporter assay was used to evaluate targeting of SIAH1, PTP4A1 and PRKCA genes by miR-944. SIAH1 protein levels were measured by Western blot. Silencing of SIAH1 gene was performed by RNA interference using shRNAs.

Results

Our data showed that miR-944 expression was severely repressed in clinical specimens and breast cancer cell lines. Suppression of miR-944 levels was independent of hormonal status and metastatic potential of breast cancer cells. Gain-of-function analysis indicated that miR-944 altered the actin cytoskeleton dynamics and impaired cell migration and invasion. Genome-wide transcriptional profiling of MDA-MB-231 cells that ectopically express miR-944 showed that 15 genes involved in migration were significantly repressed. Notably, luciferase reporter assays confirmed the ability of miR-944 to bind the 3´UTR of SIAH1 and PTP4A1 genes, but not PRKCA gene. Congruently, an inverse correlation between miR-944 and SIAH1 protein expression was found in breast cancer cells. Moreover, SIAH1 was upregulated in 75 % of miR-944-deficient breast tumors. Finally, SIAH1 gene silencing by RNA interference significantly impaired cell migration of breast cancer cells.

Conclusions

Our results pointed out that miR-944 is a novel upstream negative regulator of SIAH1 and PTP4A1 genes and provided for the first time evidence for its functional role in migration and invasion of breast cancer cells. They also suggest that miR-944 restoration may represent a potential strategy for breast cancer therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2470-3) contains supplementary material, which is available to authorized users.

Methylation Landscape of Human Breast Cancer Cells in Response to Dietary Compound Resveratrol

Aberrant DNA methylation is a frequent epigenetic alteration in cancer cells that has emerged as a pivotal mechanism for tumorigenesis. Accordingly, novel therapies targeting the epigenome are being explored with the aim to restore normal DNA methylation patterns on oncogenes and tumor suppressor genes. A limited number of studies indicate that dietary compound resveratrol modulates DNA methylation of several cancer-related genes; however a complete view of changes in methylome by resveratrol has not been reported yet. In this study we performed a genome-wide survey of DNA methylation signatures in triple negative breast cancer cells exposed to resveratrol. Our data showed that resveratrol treatment for 24 h and 48 h decreased gene promoter hypermethylation and increased DNA hypomethylation. Of 2476 hypermethylated genes in control cells, 1,459 and 1,547 were differentially hypomethylated after 24 h and 48 h, respectively. Remarkably, resveratrol did not induce widespread non-specific DNA hyper- or hypomethylation as changes in methylation were found in only 12.5% of 27,728 CpG loci. Moreover, resveratrol restores the hypomethylated and hypermethylated status of key tumor suppressor genes and oncogenes, respectively. Importantly, the integrative analysis of methylome and transcriptome profiles in response to resveratrol showed that methylation alterations were concordant with changes in mRNA expression. Our findings reveal for the first time the impact of resveratrol on the methylome of breast cancer cells and identify novel potential targets for epigenetic therapy. We propose that resveratrol may be considered as a dietary epidrug as it may exert its anti-tumor activities by modifying the methylation status of cancer -related genes which deserves further in vivo characterization.

Differential proteomic analysis reveals that EGCG inhibits HDGF and activates apoptosis to increase the sensitivity of non-small cells lung cancer to chemotherapy

PURPOSE

To search for regulated proteins in response to green tea (-)-epigallocatechin-3-gallate (EGCG) in A549 lung cancer cells.

EXPERIMENTAL DESIGN

2DE and ESI/multistage MS (ESI-MS/MS) were performed to identify modulated proteins in A549 cells treated with EGCG. Cell migration was evaluated by transwell assays. RNA interference was used to silence the hepatoma-derived growth factor (HDGF). Caspase-3, caspase-9, and HDGF were immunodetected by Western blot assays. Flow cytometry was used for detection of mitochondrial membrane potential and apoptosis.

RESULTS

We found that HDGF expression was threefold suppressed by EGCG treatment. Downregulation of HDGF by EGCG was confirmed using anti-HDGF antibodies in three lung cancer cell lines. EGCG treatment and HDGF abrogation by RNA interference resulted in a decreased migration of A549 cells. In addition, EGCG induced a marked synergistic effect with cisplatin in cell death. Consistently, an enhanced cytotoxicity in HDGF-silenced cells was also found. Cell death was associated to increased apoptosis, disruption of the mitochondrial membrane potential, and activation of caspase-3 and caspase-9.

CONCLUSION AND CLINICAL RELEVANCE

Our data suggest for the first time that abrogation of HDGF by EGCG enhances cisplatin-induced apoptosis and sensitize A549 cells to chemotherapy. Therefore, we propose that decreasing the HDGF levels by using EGCG may represent a novel strategy in lung cancer therapy.

Proteomic analysis identifies endoribouclease EhL-PSP and EhRRP41 exosome protein as novel interactors of EhCAF1 deadenylase

In higher eukaryotic cells mRNA degradation initiates by poly(A) tail shortening catalyzed by deadenylases CAF1 and CCR4. In spite of the key role of mRNA turnover in gene expression regulation, the underlying mechanisms remain poorly understood in parasites. Here, we aimed to study the function of EhCAF1 and identify associated proteins in Entamoeba histolytica. By biochemical assays, we evidenced that EhCAF1 has both RNA binding and deadenylase activities in vitro. EhCAF1 was located in cytoplasmic P-bodies that increased in number and size after cellular stress induced by DNA damage, heat shock, and nitric oxide. Using pull-down assays and ESI-MS/MS mass spectrometry, we identified 15 potential EhCAF1-interacting proteins, including the endoribonuclease EhL-PSP. Remarkably, EhCAF1 colocalized with EhL-PSP in cytoplasmic P-bodies in trophozoites. Bioinformatic analysis of EhL-PSP network proteins predicts a potential interaction with EhRRP41 exosome protein. Consistently, we evidenced that EhL-PSP colocalizes and physically interacts with EhRRP41. Strikingly, EhRRP41 did not coimmunoprecipitate EhCAF1, suggesting the existence of two EhL-PSP-containing complexes. In conclusion, our results showed novel interactions between mRNA degradation proteins and evidenced for the first time that EhCAF1 is a functional deadenylase that interacts with EhL-PSP endoribonuclease in P-bodies, while EhL-PSP interacts with EhRRP41 exosome protein in this early-branched eukaryote.

BIOLOGICAL SIGNIFICANCE

This study provides evidences for the functional deadenylase activity of EhCAF1 and shows a link between different mRNA degradation proteins in E. histolytica. By proteomic tools and pull down assays, we evidenced that EhCAF1 interacts with the putative endoribonuclease EhL-PSP, which in turn interacts with exosome EhRRP41 protein. Our data suggest for the first time the presence of two complexes, one containing the endoribonuclease EhL-PSP and the deadenylase EhCAF1 in P-bodies; and another containing the endoribonuclease EhL-PSP and the exosome EhRRP41 exoribonuclease. Overall, these results provide novel data that may help to understand mRNA decay mechanisms in this parasite.

Comparative proteomic profiling of triple-negative breast cancer reveals that up-regulation of RhoGDI-2 is associated to the inhibition of caspase 3 and caspase 9

There are no targeted therapeutic modalities for triple-negative breast cancer (TNBC), thus it is associated with poor prognosis and worst clinical outcome. Here, our aim was to identify deregulated proteins in TNBC with potential therapeutic applications. Proteomics profiling of TNBC and normal breast tissues through two-dimensional electrophoresis and ESI-MS/MS mass spectrometry revealed the existence of 16 proteins (RhoGDI-2, HSP27, SOD1, DJ1, UBE2N, PSME1, FTL, SH3BGRL, and eIF5A-1) with increased abundance in carcinomas. We also evidenced for the first time the deregulation of COX5, MTPN and DB1 proteins in TNBC that may represent novel tumor markers. Particularly, we confirmed the overexpression of the Rho-GDP dissociation inhibitor 2 (RhoGDI-2) in distinct breast cancer subtypes, as well as in metastatic cell lines derived from lung, prostate, and breast cancer. Remarkably, targeted disruption of RhoGDI-2 by RNA interference induced mitochondrial dysfunction, and facilitated caspase-3 and -9 activation in two breast cancer cell lines. Moreover, suppression of RhoGDI-2 resulted in a robust sensitization of breast cancer cells to cisplatin therapy. In conclusion, we identified novel proteins deregulated in TNBC, and confirmed the overexpression of RhoGDI-2. We propose that RhoGDI-2 inhibition may be exploited as a potential therapeutic strategy along cisplatin-based chemotherapy in breast cancer.

BIOLOGICAL SIGNIFICANCE

There are no useful biomarkers neither targeted therapeutic modalities for triple-negative breast cancer, which highly contributes to the poor prognosis of this breast cancer subtype. In this work, we used two-dimensional electrophoresis and ESI-MS/MS spectrometry to identify novel deregulated proteins in breast cancer tissues. Particularly, our results showed that RhoGDI-2, a protein that has been associated to metastasis and poor survival in human cancers, is overexpressed in different subtypes of breast tumors, as well as in metastatic cell lines derived from lung, prostate, and breast cancer. Our data also provided novel insights about the role of RhoGDI-2 in apoptosis through intrinsic pathway inhibition. Importantly, they suggested that targeted modulation of RhoGDI-2 levels might be a useful strategy for breast cancer therapy.

[Association between penoscopy data and urethral cytology among men with partners who had cervical lesions associated with human papilloma virus]

OBJECTIVE

The aim of this study was to identify human papillomavirus lesions in a group of men whose sexual partners had cervical intraepithelial lesions associated with low-grade HPV confirmed by PCR-DNA. We carried out a correlation between urethral cytology penoscopy data and PCR-DNA results.

METHODS

We studied 100 male volunteers with an age range of 21-45 (median 30 years) and divided them into two groups according to the identified virus; two groups were conformed, a high risk and a low risk virus.

RESULTS

For the penoscopy data we included the following: type of hirsutoide papillomatosis in 40 (40%) cases, common warts in 24 (24%) cases, papillomatosis in plaque in 6 (6%) and 47% displayed an urethra with a foamy appearance. In urethral cytology we did not find evidence of koilocytes in 58% and 42% showed no koilocytes. Inflammation was observed in 44 cases; an added infection was noted among 60 cases. Depending on the type of infection we found non-specific bacteria in 8%, bacillary in 10%, mixed infection in 12%, changes suggestive of Gardnerella vs 24%, and Chlamydia treatment in 6%. Dyskeratosis was noted in 47% of study participants. 67 patients were treated with imiquimod cream 5% and 33% received non-specific treatment. Regarding improvement we noted that 67 (67%) cases showed 46/67 hypochromic stains after treatment with imiquimod. Disappearance of the lesions in the penis were observed among 65 cases and only 35 remained with lesions. Regarding high-risk HPV we found a significant difference in odor (p = .004, phi = .004), urethral discharge (p = .007), pearly papules in raphe (p = .023), with inflammation, dyskeratosis and added infection (p = .000 respectively). We also noted hypochromic spots or skin discoloration after treatment with imiquimod among 5% of subjects (p = .046).

CONCLUSIONS

In our study we observed that high-risk HPV is associated with increased penile lesions and frank evidence of koilocytes in urethral cytology. We recommend that sexual partners of women with cervical lesions associated with HPV complete a control study with penoscopy data and urethral cytology, since most have concurrent infections and lesions that can treated in early stages.

E-cadherin expression in male urethral smears and correlation with PCR-based detection of human papillomavirus infection

We performed cytological examination of urethral brushing to study aberrant E-Cadherin expression as a possible marker for papillomavirus in cytological samples. A total of 30 cytobrush male urethral smears were examined E-cadherin expression and human papillomavirus (hpv) was confirmed using PCR-DNA. The age range was 19-36 years (mean: 27 years), 17 (56.7%) cases corresponded to low-risk HPV and 13 (43.3%) cases were high-risk HPV. The mean age ranges were 25.77 +/- 5.90 years for high-risk HPV and 26.77 +/- 4.31 years for low-risk HPV. Pap smears showed dyskeratosis in 23 (76.7%) cases, koilocytes in 13 (43.3%) cases, infection or bacterial background in 14 (43.7%) cases, suggestive changes of Gardnerella infection in 7 (23.3%) cases, and Chlamydia in 3 (10%) cases. Immunohistochemistry was positive for membrane E-Cadherin; there was weak expression in 13 (43.3%) cases, moderate expression in 11 (36.7%) cases (P = 0.109) (Figs. 3a and b), and strong expression in 6 (20%) cases. There were a statistically significant correlations between E-Cadherin expression and koilocytes (P = 0.007), individual cell dyskeratosis (P = 0.041), and HPV risk (P = 0.000). We concluded that the loss of E-Cadherin membrane expression was greater in high-risk HPV cases and was associated with individual cell dyskeratosis features and koilocytes. There were statistically significant correlations between E-Cadherin expression and dyskeratosis (P = 0.043), koilocytes (P = 0.007), and type of HPV (P = 0.000). Using male urethral smears to test for the loss of E-Cadherin membrane expression is simple, rapid, specific and more sensitive than conventional morphologic observations. We concluded that E-Cadherin can be used to discriminate between high- and low-risk papillomavirus in urethral cytologic specimens.

[Molecular hemato-oncology and new specific treatment strategies for leukemia]

Leukemia-associated fusion genes are detected in a significant proportion of newly diagnosed cases, where genes encoding transcription factors are usually found at one of the breakpoints. Activated fusion proteins such as Pml-Raralpha have been shown to inhibit cellular differentiation by recruitment of nuclear corepressor complexes, which maintain local histone deacetylase (HDAC) in a variety of hematologic lineage-specific gene promoters. This HDAC-dependent transcriptional repression appears as a common pathway in the development of leukemia and could constitute an important target for new therapeutic agents. Alternatively, the Bcr-Abl oncoprotein shows high tyrosine kinase activity and deregulates signal transduction pathways normally involved in both apoptosis and proliferation. This aberrant activity is affected by signal transduction inhibitors (STIs), which block or prevent the oncogenic pathway. In this review, we shed some light on our understanding of both the reversible transcriptional repression controlled by HDAC and the deregulated Bcr-Abl signal transduction pathway. In addition, the administration of low molecular weight drugs for human leukemia treatment based on this knowledge brings about a significant long-term clinical remission and an acceptable risk of toxic effects that should increase the cure rate.

Expression of triggering receptor on myeloid cell 1 and histocompatibility complex molecules in sepsis and major abdominal surgery

AIM

To evaluate the surface expression of triggering receptor on myeloid cell 1 (TREM-1), class II major histocompatibility complex molecules (HLA-DR), and the expression of the splicing variant (svTREM-1) of TREM-1 in septic patients and those subjected to major abdominal surgery.

METHODS

Using flow cytometry, we examined the surface expression of TREM-1 and HLA-DR in peripheral blood monocytes from 11 septic patients, 7 elective gastrointestinal surgical patients, and 10 healthy volunteers. svTREM-1 levels were analyzed by RT-PCR.

RESULTS

Basal expression of TREM-1 and HLA-DR in healthy volunteers was 35.91+/-14.75 MFI and 75.8+/-18.3%, respectively. In septic patients, TREM-1 expression was 59.9+/-23.9 MFI and HLA-DR expression was 44.39+/-20.25%, with a significant difference between healthy and septic groups (P<0.05) for both molecules. In the surgical patients, TREM-1 and HLA-DR expressions were 56.8+/-20.85 MFI and 71+/-13.8% before surgery and 72.65+/-29.92 MFI and 72.82+/-22.55% after surgery. TREM-1 expression was significantly different (P = 0.0087) between the samples before and after surgery and svTREM-1 expression was 0.8590+/-0.1451 MF1, 0.8820+/-0.1460 MF1, and 2.210+/-0.7873 MF1 in the healthy, surgical (after surgery) and septic groups, respectively. There was a significant difference (P = 0.048) in svTREM-1 expression between the healthy and surgical groups and the septic group.

CONCLUSION

TREM-1 expression is increased during systemic inflammatory conditions such as sepsis and the postoperative phase. Simultaneous low expression of HLA-DR molecules correlates with the severity of illness and increases susceptibility to infection. Additionally, TREM-1 expression is distinctly different in surgical patients at different stages of the inflammatory response before and after surgery. Thus, surface TREM-1 appears to be an endogenous signal during the course of the inflammatory response. svTREM-1 expression is significantly increased during sepsis, appearing to be an indicator of severity of illness. Together, these data indicate that TREM-1 may play an important role in establishing and amplifying the systemic inflammatory response. TREM-1, HLA-DR, and svTREM-1 expression analysis can provide useful diagnostic and prognostic indicators during SIRS, CARS, and sepsis.

A molecular analysis by gene expression profiling reveals Bik/NBK overexpression in sporadic breast tumor samples of Mexican females

Background

Breast cancer is one of the most frequent causes of death in Mexican women over 35 years of age. At molecular level, changes in many genetic networks have been reported as associated with this neoplasia. To analyze these changes, we determined gene expression profiles of tumors from Mexican women with breast cancer at different stages and compared these with those of normal breast tissue samples.

Methods

³²P-radiolabeled cDNA was synthesized by reverse transcription of mRNA from fresh sporadic breast tumor biopsies, as well as normal breast tissue. cDNA probes were hybridized to microarrays and expression levels registered using a phosphorimager. Expression levels of some genes were validated by real time RT-PCR and immunohistochemical assays.

Results

We identified two subgroups of tumors according to their expression profiles, probably related with cancer progression. Ten genes, unexpressed in normal tissue, were turned on in some tumors. We found consistent high expression of Bik gene in 14/15 tumors with predominant cytoplasmic distribution.

Conclusion

Recently, the product of the Bik gene has been associated with tumoral reversion in different neoplasic cell lines, and was proposed as therapy to induce apoptosis in cancers, including breast tumors. Even though a relationship among genes, for example those from a particular pathway, can be observed through microarrays, this relationship might not be sufficient to assign a definitive role to Bik in development and progression of the neoplasia. The findings herein reported deserve further investigation.