The non-vesicle cell-free DNA (cfDNA) induces cell transformation associated with horizontal DNA transfer

BACKGROUND

Cell-free DNA (cfDNA) is a source for liquid biopsy used for cancer diagnosis, therapy selection, and disease monitoring due to its non-invasive nature and ease of extraction. However, cfDNA also participates in cancer development and progression by horizontal transfer. In humans, cfDNA circulates complexed with extracellular vesicles (EV) and macromolecular complexes such as nucleosomes, lipids, and serum proteins. The present study aimed to demonstrate whether cfDNA not associated with EV induces cell transformation and tumorigenesis.

METHODS

Supernatant of the SW480 human colon cancer cell line was processed by ultracentrifugation to obtain a soluble fraction (SF) and a fraction associated with EV (EVF). Primary murine embryonic fibroblast cells (NIH3T3) underwent passive transfection with these fractions, and cell proliferation, cell cycle, apoptosis, cell transformation, and tumorigenic assays were performed. Next, cfDNA was analyzed by electronic microscopy, and horizontal transfer was assessed by human mutant KRAS in recipient cells via PCR and recipient cell internalization via fluorescence microscopy.

RESULTS

The results showed that the SF but not the EVF of cfDNA induced proliferative and antiapoptotic effects, cell transformation, and tumorigenesis in nude mice, which were reduced by digestion with DNAse I and proteinase K. These effects were associated with horizontal DNA transfer and cfDNA internalization into recipient cells.

CONCLUSIONS

The results suggest pro-tumorigenic effects of cfDNA in the SF that can be offset by enzyme treatment. Further exploration of the horizontal tumor progression phenomenon mediated by cfDNA is needed to determine whether its manipulation may play a role in cancer therapy.

PaSTe. Blockade of the Lipid Phenotype of Prostate Cancer as Metabolic Therapy: A Theoretical Proposal

BACKGROUND

Prostate cancer is the most frequently diagnosed malignancy in 112 countries and is the leading cause of death in eighteen. In addition to continuing research on prevention and early diagnosis, improving treatments and making them more affordable is imperative. In this sense, the therapeutic repurposing of low-cost and widely available drugs could reduce global mortality from this disease. The malignant metabolic phenotype is becoming increasingly important due to its therapeutic implications. Cancer generally is characterized by hyperactivation of glycolysis, glutaminolysis, and fatty acid synthesis. However, prostate cancer is particularly lipidic; it exhibits increased activity in the pathways for synthesizing fatty acids, cholesterol, and fatty acid oxidation (FAO).

OBJECTIVE

Based on a literature review, we propose the PaSTe regimen (Pantoprazole, Simvastatin, Trimetazidine) as a metabolic therapy for prostate cancer. Pantoprazole and simvastatin inhibit the enzymes fatty acid synthase (FASN) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), therefore, blocking the synthesis of fatty acids and cholesterol, respectively. In contrast, trimetazidine inhibits the enzyme 3-b-Ketoacyl-CoA thiolase (3-KAT), an enzyme that catalyzes the oxidation of fatty acids (FAO). It is known that the pharmacological or genetic depletion of any of these enzymes has antitumor effects in prostatic cancer.

RESULTS

Based on this information, we hypothesize that the PaSTe regimen will have increased antitumor effects and may impede the metabolic reprogramming shift. Existing knowledge shows that enzyme inhibition occurs at molar concentrations achieved in plasma at standard doses of these drugs.

CONCLUSION

We conclude that this regimen deserves to be preclinically evaluated because of its clinical potential for the treatment of prostate cancer.

Targeting Breast Cancer Cells with G4 PAMAM Dendrimers and Valproic Acid Derivative Complexes

BACKGROUND

Our research group has developed some Valproic Acid (VPA) derivatives employed as anti-proliferative compounds targeting the HDAC8 enzyme. However, some of these compounds are poorly soluble in water.

OBJECTIVE

Employed the four generations of Polyamidoamine (G4 PAMAM) dendrimers as drug carriers of these compounds to increase their water solubility for further in vitro evaluation.

METHODS

VPA derivatives were subjected to Docking and Molecular Dynamics (MD) simulations to evaluate their affinity on G4 PAMAM. Then, HPLC-UV/VIS, 1H NMR, MALDI-TOF and atomic force microscopy were employed to establish the formation of the drug-G4 PAMAM complexes.

RESULTS

The docking results showed that the amide groups of VPA derivatives make polar interactions with G4 PAMAM, whereas MD simulations corroborated the stability of the complexes. HPLC UV/VIS experiments showed an increase in the drug water solubility which was found to be directly proportional to the amount of G4 PAMAM. 1H NMR showed a disappearance of the proton amine group signals, correlating with docking results. MALDI-TOF and atomic force microscopy suggested the drug-G4 PAMAM dendrimer complexes formation.

DISCUSSION

In vitro studies showed that G4 PAMAM has toxicity in the micromolar concentration in MDAMB- 231, MCF7, and 3T3-L1 cell lines. VPA CF-G4 PAMAM dendrimer complex showed anti-proliferative properties in the micromolar concentration in MCF-7 and 3T3-L1, and in the milimolar concentration in MDAMB- 231, whereas VPA MF-G4 PAMAM dendrimer complex didn't show effects on the three cell lines employed.

CONCLUSION

These results demonstrate that G4 PAMAM dendrimers are capableof transporting poorly watersoluble aryl-VPA derivate compounds to increase its cytotoxic activity against neoplastic cell lines.

A Cohort Study of the Prognostic Impact of Exon-16 EZH2 Mutations in a Mexican-Mestizo Population of Patients with Diffuse Large B-Cell Lymphoma

BACKGROUND

Novel prognostic factors in patients with diffuse large B-cell lymphoma (DLBCL) are required in the era of Rituximab.

OBJECTIVE

The objective of the study was to study the prognostic impact of exon-16 enhancer-of-zeste homolog-2 (EZH2) mutations in patients with DLBCL.

METHODS

In a cohort of patients with DLBCL treated between 2015 and 2017, we analyzed the presence of EZH2 mutations and their association with clinical response (CR), relapse, progression-free survival (PFS), and overall survival (OS).

RESULTS

A total of 198 patients were included; of them, 30 (15.2%) had mutations at codon 641, in exon 16 of EZH2. Response was achieved in 151 patients (76.3%), and 43 (21.7%) relapsed or progressed during follow-up. EZH2 mutations were associated with relapse/progression (risk ratio [RR] 1.18; 95% confidence interval [CI] 0.98-1.42; p = 0.031), while a trend for not achieving a complete response was observed (RR: 0.876; 95%CI 0.74-1.038; p = 0.071). Of note, Tyr641His and Tyr641Ser EZH2 mutations were associated with shorter PFS (hazard ratio 3.234; 95% CI 1.149-9.1; p = 0.026).

CONCLUSION

The presence of EZH2 mutations was negatively associated with relapse/progression and showed a trend for lack of complete response. Further studies are needed to define better the prognostic significance of these mutations in Mexican-Mestizo DLBCL patients.

The role of extracellular DNA (exDNA) in cellular processes

Nowadays, extracellular DNA or circulating cell-free DNA is considered to be a molecule with clinical applications (diagnosis, prognosis, monitoring of treatment responses, or patient follow-up) in diverse pathologies, especially in cancer. Nevertheless, because of its molecular characteristics, it can have many other functions. This review focuses on the participation of extracellular DNA (exDNA) in fundamental processes such as cell signaling, coagulation, immunity, evolution through horizontal transfer of genetic information, and adaptive response to inflammatory processes. A deeper understanding of its role in each of these processes will allow development of better tools to monitor and control pathologies, as well as helping to generate new therapeutic options, beyond the applicability of DNA in liquid biopsy.

IMMUNOTHERAPY TREATMENT AGAINST CERVICAL CANCER

Cervical cancer (CC) is one of the most common gynecological tumors and an important health problem, especially in developing countries. The vast majority of patients in early stages are cured of the disease with surgical treatment and with concomitant chemoradiotherapy in locally advanced stages. However, in patients with recurrent, persistent, or metastatic cervical CC, the effectiveness of treatment is limited, except for the combination of chemotherapy based on platinum doublets plus bevacizumab, the treatment that has achieved the best results to date. Programmed cell death-1/PD ligand-1 (PD-1/PD-L1) inhibitors could be a novel and cutting-edge therapeutic option to improve clinical outcomes in this group of patients. Thus far, there are a few Phase I/II clinical trials that have assessed the usefulness of pembrolizumab and nivolumab in this group of patients; these include the KEYNOTE 028, KEYNOTE 158, and CHECKMATE 358 trials, in which clinical benefit has been proven with PD-1/PD-L1 inhibitors in recurrent, persistent, or metastatic CC, as second-line treatment. There are also some ongoing trials that could provide further evidence on the PD-1/PD-L1 pathway as a therapeutic target in CC. In this review, we will focus on the usefulness of these PD-1/PDL1 inhibitors in CC, as well as on trials that are still in the recruitment phase, to confirm their effectiveness in this clinical setting.

Late-Onset Hematological Toxicity (LOHT) in Patients with B-Cell Lymphomas: A Survey in 758 Cases

BACKGROUND

The increasing survival of patients with non-Hodgkin lymphoma has allowed the diagnosis of long-term com- plications, including late-onset hematological toxicity (LOHT), transitory cytopenias, or therapy-related myeloid neoplasm (t-MDS/t-AML).

OBJECTIVE

The objective of the study was to determine the frequency and clinical evolution of LOHT in patients with lymphoproliferative malignancies.

MATERIALS AND METHODS

Two cohorts of patients B-cell lymphomas were reviewed. Patients who achieved full hematologic recovery at the end of treatment, and thereafter developed any degree of cytopenia were included in the study. Clinical and biochemical parameters were compared between patients with and without cytopenias with X2 test. Bi-and multivariate analyses were performed to evaluate factors associated with the development of late-onset cytopenias.

RESULTS

Of 758 patients enrolled, 19 developed cytopenias (2.5%). Transitory cytopenia was documented in 6 cases, 3 developed ICUS, 8 t-MDS, and 2 t-AML. In patients with FL, only hemoglobin < 12 g/dL (p = 0.032) and >6 nodal areas (p = 0.037) at diagnosis were factors statistically significant for the development of cytopenia. During cytopenias, 55% of patients died.

CONCLUSIONS

LOHT constitutes a cause of morbidity and mortality in 2.5% of lymphoma patients treated with different therapy regimens.

In Vitro Employment of Recombinant Taenia solium Calreticulin as a Novel Strategy Against Breast and Ovarian Cancer Stem-like Cells

BACKGROUND AND AIMS

Calreticulin is a chaperone and master regulator of intracellular calcium homeostasis. Several additional functions have been discovered. Human and parasite calreticulin have been shown to suppress mammary tumor growth in vivo. Here, we explored the capacity of recombinant Taenia solium calreticulin (rTsCRT) to modulate cancer cell growth in vitro.

METHODS

We used different concentrations of rTsCRT to treat cancer cell lines and analyzed viability and colony formation capacity. We also tested the combination of the IC₂₀ or IC₅₀ doses of rTsCRT and of the chemotherapeutic drug 5-fluorouracil on MCF7 and SKOV3 cell lines. As a control, the non-tumorigenic cell line MCF10-A was employed. The effect of the drug combinations was also assessed in cancer stem-like cells. Additionally, scavenger receptor ligands were employed to identify the role of this receptor in the rTsCRT anti-tumoral effect.

RESULTS

rTsCRT has a dose-dependent in vitro anti-tumoral effect, being SKOV3 the most sensitive cell line followed by MCF7. When rTsCRT/5-fluorouracil were used, MCF7 and SKOV3 showed a 60% reduction in cell viability; colony formation capacity was also diminished. Treatment of cancer stem-like cells from MCF7 showed a higher reduction in cell viability, while those from SKOV3 were more sensitive to colony disaggregation. Finally, pharmacological inhibition of the scavenger receptor, abrogated the reduction in viability induced by rTsCRT in both the parental and stem-like cells.

CONCLUSION

Our data suggest that rTsCRT alone or in combination with 5-fluorouracil inhibits the growth of breast and ovarian cancer cell lines through its interaction with scavenger receptors.

Drug repurposing for cancer therapy, easier said than done

Drug repurposing for cancer therapy is currently a hot topic of research. Theoretically, in contrast to the known hurdles of developing new molecular entities, the approach of repurposing has several advantages. Mostly, it is said that it is faster, safer, easier, and cheaper. In the real world, however, there are only three repurposed drugs so far, that are listed in widely recognized cancer guidelines, but a large number of them are being studied. Among the many barriers to repurposing cancer drugs, economical-driven are the most important that difficult the clinical development of them. In this review, we provide an overview of the current status of drug repurposing for cancer therapy and the barriers that need to be overcome to realize the benefit of this approach. It means to have repositioned drugs for cancer therapy accepted as standard therapy for cancer indications at low cost.

Computational Study of the Binding Modes of Diverse DPN Analogues on Estrogen Receptors (ER) and the Biological Evaluation of a New Potential Antiestrogenic Ligand

Estrogen (17β-estradiol) is essential for normal growth and differentiation in the mammary gland. In the last three decades, previous investigations have revealed that Estrogen Receptor Alpha (ERα) plays a critical role in breast cancer. More recently, observations regarding the widespread expression of ERβ-like proteins in normal and neoplastic mammary tissues have suggested that ERβ is also involved in the mentioned pathology. Design of new drugs both steroidal and nonsteroidal that target any of these receptors represents a promise to treat breast cancer although it remains a challenge due to the sequence similarity between their catalytic domains. In this work, we propose a new set of compounds that could effectively target the estrogen receptors ERα and ERβ. These ligands were designed based on the chemical structure of the ERβ-selective agonist Diarylpropionitrile (DPN). The designed ligands were submitted to in silico ADMET studies, yielding in a filtered list of ligands that showed better drug-like properties. Molecular dynamics simulations of both estrogen receptors and docking analysis were carried-out employing the designed compounds, from which two were chosen due to their promising characteristics retrieved from theoretical results (docking analysis or targeting receptor predictions). They were chemically synthetized and during the process, two precursor ligands were also obtained. These four ligands were subjected to biological studies from which it could be detected that compound mol60b dislplayed inhibitory activity and its ability to activate the transcription via an estrogenic mechanism of action was also determined. Interestinly, this observation can be related to theoretical binding free energy calculations, where the complex: ERβ-mol60b showed the highest energy ΔGbind value in comparison to others.

Selection of a GPER1 Ligand via Ligand-based Virtual Screening Coupled to Molecular Dynamics Simulations and Its Anti-proliferative Effects on Breast Cancer Cells

BACKGROUND

Recent reports have demonstrated the role of the G Protein-Coupled Estrogen Receptor 1 (GPER1) on the proliferation of breast cancer. The coupling of GPER1 to estrogen triggers cellular signaling pathways related to cell proliferation.

OBJECTIVE

Develop new therapeutic strategies against breast cancer.

METHOD

We performed in silico studies to explore the binding mechanism of a set of G15 /G1 analogue compounds. We included a carboxyl group instead of the acetyl group from G1 to form amides with several moieties to increase affinity on GPER1. The designed ligands were submitted to ligand-based and structure-based virtual screening to get insights into the binding mechanism of the best designed compound and phenol red on GPER1.

RESULTS

According to the in silico studies, the best molecule was named G1-PABA ((3aS,4R,9bR)-4-(6- bromobenzo[d][1,3]dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-carboxylic acid). It was synthesized and assayed in vitro in breast cancer (MCF-7 and MDA-MB-231) and normal (MCF-10A) cell lines. Experimental studies showed that the target compound was able to decrease cell proliferation, IC50 values of 15.93 µM, 52.92 µM and 32.45 µM in the MCF-7, MDA-MB-231 and MCF-10A cell lines, respectively, after 72 h of treatment. The compound showed better IC50 values without phenol red, suggesting that phenol red interfere with the G1-PABA action at GPER1, as observed through in silico studies, which is present in MCF-7 cells according to PCR studies and explains the cell proliferation effects.

CONCLUSION

Concentration-dependent inhibition of cell proliferation occurred with G1-PABA in the assayed cell lines and could be due to its action on GPER1.

Antimetastatic effect of epigenetic drugs, hydralazine and valproic acid, in Ras-transformed NIH 3T3 cells

Introduction

Metastasis involves the accumulation of genetic and epigenetic alterations leading to activation of prometastatic genes and inactivation of antimetastatic genes. Among epigenetic alterations, DNA hypermethylation and histone hypoacetylation are the focus of intense translational research because their pharmacological inhibition has been shown to produce antineoplastic activity in a variety of experimental models.

Aims

This study aimed to evaluate the antimetastatic effect of the DNA-methylation inhibitor, hydralazine, and the histone deacetylase inhibitor, valproic acid.

Methods

NIH 3T3-Ras murine cells were treated with hydralazine and valproic acid to evaluate their effects upon cell proliferation, cell motility, chemotaxis, gelatinase activity, and gene expression. Lung metastases were developed by intravenous injection of NIH 3T3-Ras cells in BALB/c nu/nu mice and then treated with the drug combination.

Results

Treatment induced a growth-inhibitory effect on NIH 3T3-Ras cells, showed a trend toward increased gelatinase activity of MMP2 and MMP9, and inhibited chemotaxis and cell motility. The combination led to a strong antimetastatic effect in lungs of nude mice.

Conclusion

Hydralazine and valproic acid, two repositioned drugs as epigenetic agents, exhibit antimetastatic effects in vitro and in vivo and hold potential for cancer treatment.

Epidemiological Data on the Nutritional Status of Cancer Patients Receiving Treatment with Concomitant Chemoradiotherapy, Radiotherapy or Sequential Chemoradiotherapy to the Abdominopelvic Area

Cancer patients are particularly susceptible to undernourishment so associated weight loss is frequent. Approximately 15% of patients lose >10% of their usual body weight, 40-80% become undernourished, and about 20% die as a result. Well-nourished patients have a higher survival rate when compared with patients at risk of undernourishment (19.9 vs. 3.7 months); hence, nutritional intervention is pivotal. Undernourishment negatively influences the patient's prognosis, and its prevalence depends on the tumor type and location, disease stage, treatment, and the applied nutritional evaluation tool. During abdominopelvic radiotherapy, up to 90% of patients experience symptoms of varying severity; weight loss during radiotherapy is an early indicator of nutritional deterioration, and he the use of radiation is associated with a higher likelihood of undernourishment. In patients with gynecological malignancies, 12.5-54% are malnourished before receiving oncological treatment, worsening after treatment in 35.8-82% of cases. There is also deterioration of the nutritional status in patients with colorectal cancer once pelvic radiotherapy is initiated, whereby 50% of cases are malnourished at the beginning of treatment, and 66.7% are so when it ends. Although there are notable differences in the impact of radiotherapy on weight according to the radiated region, 88% patients receiving abdominal radiotherapy were found to lose weight compared to 38% of patients whose treatment was limited to the pelvis.

Advancing clinical research globally: Cervical cancer research network from Mexico

Cervical cancer is the fourth most common cancer in women with 85% of the mortality burden occurring in less-developed regions of the world. The Cervix Cancer Research Network (CCRN) was founded by the Gynecologic Cancer InterGroup (GCIG) with a mission to improve outcomes in cervix cancer by increasing access to high-quality clinical trials worldwide, with particular attention to less-developed, underrepresented sites. The CCRN held its second international educational symposium in Mexico City with ninety participants from fifteen Latin America countries in January 2017. The purpose of this symposium was to advance knowledge in cervix cancer therapy, promote recruitment to CCRN clinical trials, and to identify relevant future CCRN clinical trial concepts that could improve global care standards for women with cervical cancer.

•

Cervix cancer is the fourth most common cancer in women worldwide with up to an 18-fold disparity in mortality rates.

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The Cervix Cancer Research Network (CCRN) aims to increase access to clinical trials in order to improve outcomes for women.

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The 2nd CCRN international symposium was held in Mexico City including 90 participants from 15 Latin American countries.

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CCRN clinical trials were discussed, including new trials proposed of hypofractionation and HPV targeted therapy.

Comparison of DNA demethylating and histone deacetylase inhibitors hydralazine-valproate versus vorinostat-decitabine incutaneous t-cell lymphoma in HUT78 cells

PURPOSE

Cutaneous T-cell lymphoma (CTCL) is an uncommon extranodal non-Hodgkin T-cell lymphoma that originates from mature T lymphocytes homed at the skin. Epigenetic alterations observed in CTCL are not limited to overexpression of Histone Deacetylases but also to DNA hypermethylation. The known synergy between Histone deacetylase inhibitors (HDACi) and DNA methyltransferases inhibitors (DNMTi) suggests that combining these agent classes could be effective for CTCL.

METHODS

In this study, the combinations of the HDACi and DNMTi hydralazine/valproate (HV) and vorinostat/decitabine (VD) were compared in regard to viability inhibition, clonogenicity, pharmacological interaction and cell cycle effects in the CTCL cell line Hut78. In addition, the effect of these combinations was evaluated in normal peripheral blood mononuclear cells.

RESULTS

The results show that each of the DNMTi and HDACi exerts growth inhibition, mostly by inducing apoptosis as shown in the cell cycle distribution. However, in the combination of HV the interaction is more synergic and also it inhibits the clonogenic capacity of cells over time. Additionally, the HV combination seems to affect in a minor degree the viability of peripheral blood mononuclear cells.

CONCLUSIONS

The results of this study and the preclinical and clinical evidence on the efficacy of combining HDACi with DNMTi strongly suggest that more studies are needed with this drug class combination in CTCL, particularly with the hydralazine-valproate scheme, which is safe, and these drugs are widely available and administered by oral route.

Orlistat as a FASN inhibitor and multitargeted agent for cancer therapy

INTRODUCTION

Cancer cells have increased glycolysis and glutaminolysis. Their third feature is increased de novo lipogenesis. As such, fatty acid (FA) synthesis enzymes are over-expressed in cancer and their depletion causes antitumor effects. As fatty acid synthase (FASN) plays a pivotal role in this process, it is an attractive target for cancer therapy.

AREAS COVERED

This is a review of the lipogenic phenotype of cancer and how this phenomenon can be exploited for cancer therapy using inhibitors of FASN, with particular emphasis on orlistat as a repurposing drug.

EXPERT OPINION

Disease stabilization only has been observed with a highly selective FASN inhibitor used as a single agent in clinical trials. It is too early to say whether the absence of tumor responses other than stabilization results because even full inhibition of FASN is not enough to elicit antitumor responses. The FASN inhibitor orlistat is a 'dirty' drug with target-off actions upon at least seven targets with a proven role in tumor biology. The development of orlistat formulations suited for its intravenous administration is a step ahead to shed light on the concept that drug promiscuity can or not be a virtue.

Ultrasound, histopathological, and genetic features of uveal melanoma in a Mexican-Mestizo population

OBJECTIVE

To describe the ultrasound, histopathological and genetic characteristics of uveal melanoma in a Mexican-Mestizo population.

MATERIAL AND METHODS

A total of 39 enucleated eyes with a histopathological diagnosis of uveal melanoma were assessed by describing the clinical findings, and ultrasound, histopathological and genetic features.

RESULTS

A high correlation was observed between tumour height measurement using ultrasound and histopathology. In our cases, tumour size and reflectivity were higher compared with those reported in the literature. The preliminary data on the molecular assessment of the tumours show the presence of an unreported polymorphism (T>C IVS5+34) and one sample with GNAQ mutation (A>C CAA>CCA Gln 209 Pro).

CONCLUSION

Ultrasound is a reliable method to identify the size of the tumour. Furthermore, knowledge of the molecular mechanisms promises new perspectives for the development of new targeted therapeutics. Fortunately this leads to progress in the treatment of patients with metastatic disease or prevents it in those at high risk.

Ivermectin as an inhibitor of cancer stem‑like cells

The aim of the present study was to demonstrate that ivermectin preferentially inhibited cancer stem‑like cells (CSC) in breast cancer cells and downregulated the expression of 'stemness' genes. Computational searching of DrugBank, a database of approved drugs, was performed using the principles of two‑dimensional similarity searching; the chemical structure of salinomycin was used as a query. Growth inhibition of the breast cancer cell lin e MDA‑MB‑231 by ivermectin was investigated in the total cell population, in cell spheroids and in sorted cells that expressed cluster of differentiation (CD)44+/CD24‑. The effects of ivermectin treatment on the expression of pluripotency and self‑renewal transcription factors, such as homeobox protein nanog (nanog), octamer‑binding protein 4 (oct‑4) and SRY‑box 2 (sox‑2), were evaluated by reverse transcription‑quantitative polymerase chain reaction and western blotting. Ivermectin exhibited a similarity value of 0.78 in reference to salinomycin. Ivermectin demonstrated an inhibitory effect upon the growth of MDA‑MB‑231 cells in the range of 0.2‑8 µM. Ivermectin preferentially inhibits the viability of CSC‑enriched populations (CD44+/CD24‑ and cells growing in spheroids) compared with the total cell population. The opposite pattern was observed with paclitaxel treatment. Ivermectin exposure reduced the expression of nanog, oct‑4 and sox‑2 at the mRNA and protein levels. Ivermectin preferentially inhibited the CSC subpopulation in the MDA‑MB‑231 cells and downregulated the expression of genes involved in the maintenance of pluripotency and self‑renewal.

Exploring disparities in incidence and mortality rates of breast and gynecologic cancers according to the Human Development Index in the Pan-American region

OBJECTIVE

To evaluate whether a country's Human Development Index (HDI) can help explain the differences in the country's breast cancer and gynecological cancer incidence and mortality rates in the Pan-American region.

STUDY DESIGN

Ecological analysis.

METHODS

Pan-American region countries with publicly available data both in GLOBOCAN 2012 and the United Nations Development Report 2012 were included (n = 28). Incidence and mortality rates age-standardized per 100,000 were natural log-transformed for breast cancer, ovarian cancer, corpus uteri cancer, and cervical cancer. The mortality-to-incidence ratio (MIR) was calculated for each site. Pearson's correlation test and a simple linear regression were performed.

RESULTS

The HDI showed a positive correlation with breast cancer and ovarian cancer incidence and mortality rates, respectively, and a negative correlation with cervical cancer incidence and mortality rates. The HDI and corpus uteri cancer showed no association. MIR and the HDI showed a negative correlation for all tumor types except ovarian cancer. An increment in 1 HDI unit leads to changes in cancer rates: in breast cancer incidence β = 4.03 (95% confidence interval [CI] 2.61; 5.45) P < 0.001, breast cancer mortality β = 1.76 (95% CI 0.32; 3.21) P = 0.019, and breast cancer-MIR β = -0.705 (95% CI 0.704; 0.706) P < 0.001; in cervical cancer incidence β = -3.28 (95% CI -4.78; -1.78) P < 0.001, cervical cancer mortality β = -4.63 (95% CI -6.10; -3.17) P < 0.001, and cervical cancer-MIR β = -1.35 (95% CI -1.83; -0.87) P < 0.001; in ovarian cancer incidence β = 3.26 (95% CI 1.78; 4.75) P < 0.001, ovarian cancer mortality β = 1.82 (95% CI 0.44; 3.20) P = 0.012, and ovarian cancer-MIR β = 5.10 (95% CI 3.22; 6.97) P < 0.001; in corpus uteri cancer incidence β = 2.37 (95% CI -0.33; 5.06) P = 0.83, corpus uteri cancer mortality β = 0.68 (95% CI -2.68; 2.82) P = 0.96, and corpus uteri cancer-MIR β = -2.30 (95% CI -3.19; -1.40) P < 0.001.

CONCLUSIONS

A country's HDI should be considered to understand disparities in breast cancer and gynecological cancer in the Pan-American region.

Understanding tumor anabolism and patient catabolism in cancer-associated cachexia

Cachexia is a multifactorial paraneoplastic syndrome commonly associated with advanced stages of cancer. Cachexia is responsible for poor responses to antitumoral treatment and death in close to one-third of affected patients. There is still an incomplete understanding of the metabolic dysregulation induced by a tumor that leads to the appearance and persistence of cachexia. Furthermore, cachexia is irreversible, and there are currently no guidelines for its diagnosis or treatments for it. In this review, we aim to discuss the current knowledge about cancer-associated cachexia, starting with generalities about cancer as the generator of this syndrome, then analyzing the characteristics of cachexia at the biochemical and metabolic levels in both the tumor and the patient, and finally discussing current therapeutic approaches to treating cancer-associated cachexia.

Efficacy of hydralazine and valproate in cutaneous T-cell lymphoma, a phase II study

OBJECTIVES

To evaluate the activity and safety of hydralazine and valproate (Transkrip) in cutaneous T-cell lymphoma (CTCL).

METHODS

Previously untreated and progressive/refractory CTCL patients received hydralazine at 83 mg or 182 mg/day for slow and rapid acetylators respectively plus magnesium valproate at a total dose of 30 mg/Kg t.i.d daily in continuous 28-day cycles in this phase II study. The primary objective was overall response rate (ORR) measured by the modified severity weighted assessment tool (m-SWAT), secondary end-points were time to response (TTR), time to progression (TTP), duration of response (DOR), progression-free survival (PFS), overall survival (OS) and safety.

RESULTS

Fourteen patients were enrolled (7 untreated and 7 pretreated). ORR was 71% with 50% complete and 21% partial. Two had stable disease and two progressed. At a median follow-up of 36 months (5-52), median TTR was 2 months (1-4); median DOR was 28 months (5-45); median PFS 36 and not reached for OS. There were no differences in median TTR, DOR, and PFS between treated and pretreated patients. Pruritus relieve was complete in 13 out of 14 patients. No grade 3 or 4 toxicities were observed.

CONCLUSION

The combination of hydralazine and valproate is safe, very well tolerated and effective in CTCL.

N-(2-hydroxyphenyl)-2-propylpentanamide, a valproic acid aryl derivative designed in silico with improved anti-proliferative activity in HeLa, rhabdomyosarcoma and breast cancer cells

Epigenetic alterations are associated with cancer and their targeting is a promising approach for treatment of this disease. Among current epigenetic drugs, histone deacetylase (HDAC) inhibitors induce changes in gene expression that can lead to cell death in tumors. Valproic acid (VPA) is a HDAC inhibitor that has antitumor activity at mM range. However, it is known that VPA is a hepatotoxic drug. Therefore, the aim of this study was to design a set of VPA derivatives adding the arylamine core of the suberoylanilide hydroxamic acid (SAHA) with different substituents at its carboxyl group. These derivatives were submitted to docking simulations to select the most promising compound. The compound 2 (N-(2-hydroxyphenyl)-2-propylpentanamide) was the best candidate to be synthesized and evaluated in vitro as an anti-cancer agent against HeLa, rhabdomyosarcoma and breast cancer cell lines. Compound 2 showed a better IC₅₀ (μM range) than VPA (mM range) on these cancer cells. And also, 2 was particularly effective on triple negative breast cancer cells. In conclusion, 2 is an example of drugs designed in silico that show biological properties against human cancer difficult to treat as triple negative breast cancer.

Antitumor Effects of Systemic DNAse I and Proteases in an In Vivo Model

Background. Cell-free DNA circulates in cancer patients and induces in vivo cell transformation and cancer progression in susceptible cells. Based on this, we hypothesized that depletion of circulating DNA with DNAse I and a protease mix could have antitumor effects. Study design. The study aimed to demonstrate that DNAse I and a protease mix can degrade in vitro DNA and proteins from the serum of healthy individuals and cancer patients, and in vivo in serum of Wistar rats,. Moreover, the antitumor effect of the systemically administered enzyme mix treatmentwas evaluated in nude mice subcutaneously grafted with the human colon cancer cell line SW480. Results. The serum DNA of cancer patients or healthy individuals was almost completely degraded in vitro by the enzymatic treatment, but no degradation was found with the enzymes given separately. The intravenous administration of the enzymes led to significant decreases in DNA and proteins from rat serum. No antitumor effect was observed in immunodeficient mice treated with the enzymes given separately. In contrast, the animals that received both enzymes exhibited a marked growth inhibition of tumors, 40% of them having pathological complete response. Conclusion. This study demonstrated that systemic treatment with DNAse I and a protease mix in rats decreases DNA and proteins from serum and that this treatment has antitumor effects. Our results support the hypothesis that circulating DNA could have a role in tumor progression, which can be offset by depleting it. Further studies are needed to prove this concept.

G80A Single Nucleotide Polymorphism in Reduced Folate Carrier-1 Gene in a Mexican Population and its Impact on Survival in Patients with Acute Lymphoblastic Leukemia

BACKGROUND

Hyper-CVAD is the treatment for patients with acute lymphoblastic leukemia in our institution.

OBJECTIVE

To evaluate the impact of single nucleotide polymorphisms at genes associated with methotrexate metabolism on survival.

METHODS

The presence of the single nucleotide polymorphisms G80A at reduced folate carrier-1 gene and C677T in the methylenetetrahydrofolate reductase gene was determined by denaturing high performance liquid chromatography and validated by sequencing. Both single nucleotide polymorphisms were evaluated in 71 healthy donors and in an exploratory pilot trial with acute lymphoblastic leukemia patients to determine the influence of these single nucleotide polymorphisms on clinical outcome. Clinical characteristics, response, and outcome were registered. A Cox regression analysis was done to evaluate factors influencing response and overall survival.

RESULTS

There were no differences in the frequency of single nucleotide polymorphisms between volunteers and acute lymphoblastic leukemia patients according to the Hardy-Weinberg test. Sensitivity and specificity were 72 and 91% for the G80A, and 64 and 75% for the C677T, respectively. The multivariate analysis showed that the T-immunophenotype and the presence of single nucleotide polymorphism G80A reduced folate carrier-1 were associated with a shorter relapse-free survival and overall survival.

CONCLUSIONS

The presence of G80A single nucleotide polymorphism at reduced folate carrier-1 gene in acute lymphoblastic leukemia patients was associated with a poorer prognosis.

A pilot study of nimotuzumab plus single agent chemotherapy as second- or third-line treatment or more in patients with recurrent, persistent or metastatic cervical cancer

Nimotuzumab is a humanized IgG1 monoclonal antibody against the EGFR extracellular domain that has been evaluated in solid tumors as a single agent or in combination with chemotherapy and radiation. Cervical cancer patients who are refractory or progressive to first-line chemotherapy have a dismal prognosis, and no second- or third-line chemotherapy is considered standard. This pilot trial aimed to evaluate the efficacy and safety of nimotuzumab in 17 patients with pre-treated advanced refractory or progressive cervical cancer. Nimotuzumab was administered weekly at 200 mg/m(2) as single agent for 4 weeks (induction phase), then concurrent with 6 21-day cycles of gemcitabine (800 mg/m(2)) or cisplatin (50 mg/m(2)) for 18 weeks (concurrent phase) and then once every 2 weeks (maintenance phase). Nimotuzumab could be continued beyond disease progression. Seventeen patients were accrued and evaluated for safety and efficacy. The median number of nimotuzumab applications was 20 (5-96). The median number of chemotherapy cycles administered was 6 (1-6). No toxicity occurred during induction and maintenance phases (single agent nimotuzumab). In the concurrent phase, grade 3 toxicity events observed were leucopenia, anemia and diarrhea in 11.7%, 5.8% and 11.7% respectively. No complete or partial responses were observed. The stable disease (SD) rate was 35%. The median PFS and OS rates were 163 days (95% CI, 104 to 222), and 299 days (95% IC, 177 to 421) respectively. Nimotuzumab is well tolerated and may have a role in the treatment of advanced cervical cancer.

The safety of drug treatments for cervical cancer

INTRODUCTION

The treatment of some early-stage and most locally advanced disease cervical cancer patients consists of concurrent chemoradiation, while almost all with advanced disease require palliative chemotherapy.

AREAS COVERED

This review is aimed to analyze the safety issues emerging from trials of chemoradiation for early-stage high-risk disease and locally advanced stages, as well as safety issues of trials of palliative chemotherapy for advanced disease. Safety issues on fertility preservation are also discussed.

EXPERT OPINION

Cisplatin chemoradiation produces higher toxicity as compared to radiation alone, yet it is well-tolerated. Further advances would require (i) the development of more effective and tolerated combination chemoradiation regimens, (ii) demonstration of the efficacy and tolerability of adjuvant chemotherapy after cisplatin chemoradiation, and (iii) incorporation of targeted therapies into radiosensitizing regimens. A major problem continues to be the population of patients with advanced disease. The recent incorporation of bevacizumab into chemotherapy regimens represents a step forward; however, toxicity as well as economic issues may impede its wide acceptance worldwide. Preserving fertility in young women with cervical cancer is an issue that must be fully addressed. In this setting, neoadjuvant chemotherapy seems to increase fertlity rate without compromising oncological outcomes.

Reviving Lonidamine and 6-Diazo-5-oxo-L-norleucine to Be Used in Combination for Metabolic Cancer Therapy

Abnormal metabolism is another cancer hallmark. The two most characterized altered metabolic pathways are high rates of glycolysis and glutaminolysis, which are natural targets for cancer therapy. Currently, a number of newer compounds to block glycolysis and glutaminolysis are being developed; nevertheless, lonidamine and 6-diazo-5-oxo-L-norleucine (DON) are two old drugs well characterized as inhibitors of glycolysis and glutaminolysis, respectively, whose clinical development was abandoned years ago when the importance of cancer metabolism was not fully appreciated and clinical trial methodology was less developed. In this review, a PubMed search using the words lonidamine and 6-diazo-5-oxo-L-norleucine (DON) was undertaken to analyse existing information on the preclinical and clinical studies of these drugs for cancer treatment. Data show that they exhibit antitumor effects; besides there is also the suggestion that they are synergistic. We conclude that lonidamine and DON are safe and potentially effective drugs that need to be reevaluated in combination as metabolic therapy of cancer.

Antitumor effects of a drug combination targeting glycolysis, glutaminolysis and de novo synthesis of fatty acids

There is a strong rationale for targeting the metabolic alterations of cancer cells. The most studied of these are the higher rates of glycolysis, glutaminolysis and de novo synthesis of fatty acids (FAs). Despite the availability of pharmacological inhibitors of these pathways, no preclinical studies targeting them simultaneously have been performed. In the present study it was determined whether three key enzymes for glycolysis, glutaminolysis and de novo synthesis of FAs, hexokinase-2, glutaminase and fatty acid synthase, respectively, were overexpressed as compared to primary fibroblasts. In addition, we showed that at clinically relevant concentrations lonidamine, 6-diazo-5-oxo-L-norleucine and orlistat, known inhibitors of the mentioned enzymes, exerted a cell viability inhibitory effect. Genetic downregulation of the three enzymes also reduced cell viability. The three drugs were highly synergistic when administered as a triple combination. Of note, the cytotoxicity of the triple combination was low in primary fibroblasts and was well tolerated when administered into healthy BALB/c mice. The results suggest the feasibility and potential clinical utility of the triple metabolic targeting which merits to be further studied by using either repositioned old drugs or newer, more selective inhibitors.

Emerging drugs for the treatment of cervical cancer

INTRODUCTION

Worldwide, most cervical cancer (CC) patients require the use of drug therapy either adjuvant, concurrent with radiation or palliative.

AREAS COVERED

This review briefly discusses the current achievements in treating CC with an emphasis in emerging agents.

EXPERT OPINION

Concurrent cisplatin with radiation and lately, gemcitabine-cisplatin chemoradiation has resulted in small but significant improvements in the treatment of locally advanced and high-risk early-stage patients. So far, only antiangiogenic therapy with bevacizumab added to cisplatin chemoradiation has demonstrated safety and encouraging results in a Phase II study. In advanced disease, cisplatin doublets yield median survival rates not exceeding 14 months. The first Phase III study of bevacizumab, added to standard chemotherapy cisplatin- or non-cisplatin-containing doublet, has shown significant increase in both overall survival and progression-free survival. Further studies are needed before bevacizumab plus chemotherapy can be considered the standard of care for advanced disease. The characterization of the mutational landscape of CC and developments of novel targeted therapies may result in more effective and individualized treatments for CC. The potential efficacy of knocking down the key alterations in CC, E6 and E7 human papilloma virus oncoproteins must not be overlooked.

Discovery and development of DNA methyltransferase inhibitors using in silico approaches

Multiple strategies have evolved during the past few years to advance epigenetic compounds targeting DNA methyltransferases (DNMTs). Significant progress has been made in HTS, lead optimization and determination of 3D structures of DNMTs. In light of the emerging concept of epi-informatics, computational approaches are employed to accelerate the development of DNMT inhibitors helping to screen chemical databases, mine the DNMT-relevant chemical space, uncover SAR and design focused libraries. Computational methods also synergize with natural-product-based drug discovery and drug repurposing. Herein, we survey the latest developments of in silico approaches to advance epigenetic drug and probe discovery targeting DNMTs.

Nicotinamide sensitizes human breast cancer cells to the cytotoxic effects of radiation and cisplatin

Poly(ADP-ribose) polymerase (PARP) inhibitors enhance the effect of DNA alkylating agents on BRCA1‑ and BRCA2-deficient cell lines. The aim of this study was to analyze the effect of the PARP inhibitor nicotinamide (NAM) on breast cancer cells with different BRCA1 expression or function, such as BRCA1‑deficient MDA-MB-436 cells, low expression BRCA1 MCF-7 cells, and the BRCA1 wild‑type MDA-MB-231 cells, to demonstrate its effects as a chemo‑ or radiosensitizing agent. PARP activity was analyzed in MDA-MB-436, MCF-7 and MDA-MB-231 breast cancer cells subjected or not to NAM. Inhibition of PARP by NAM in the presence of DNA damage was examined by Alexa Fluor 488 immunofluorescence. Crystal violet assays were used to test growth inhibition and the chemo‑ and radiosensitization effects of NAM were investigated using clonogenic assays. Significant differences among data sets were determined using two-tailed ANOVA and Bonferroni tests. We demonstrated that NAM reduces PARP activity in vitro, and in cells subjected or not to DNA damage, it also reduces the viability of breast cancer cell lines and synergyzes the cytotoxicity of cisplatin in MDA-MB-436 and MCF-7 cells. Downregulation of PARP1 with siRNA led to modest growth inhibition, which was further increased by cisplatin. Nicotinamide also induced radiosensitization in MDA-MB-436 and MDA-MB-231 cells. In conclusion, NAM may be used as a chemo‑ or radiosensitizing agent regardless of the BRCA1 status in breast cancer.

Genetic selection of volunteers and concomitant dose adjustment leads to comparable hydralazine/valproate exposure

WHAT IS KNOWN AND OBJECTIVE

Hydralazine is an inhibitor of DNA methyltransferases, whereas valproate interferes with histone deacetylation. In combination, they show a marked synergism in reducing tumour growth as well as development of metastasis and inducing cell differentiation. Hydralazine is metabolized by the highly polymorphic N-acetyltransferase 2. The current pilot study was performed to analyse the pharmacokinetic parameters of a single dose of hydralazine in 24 h (one tablet with 83 mg for slow acetylators and one tablet with 182 mg for fast acetylators) and three fixed doses of valproate (one tablet of controlled liberation with 700 mg every 8 h) in healthy genetically selected volunteers. Selection was performed based on their NAT2 activity as deduced from their genotype.

METHODS

An open label non-randomized single arm study was conducted in two groups of six healthy volunteers of both genders aged 20-45 years with a body mass index 22·2-26·9 which were classified as fast or slow acetylators after genotyping 3 SNPs that cover 99·9% of the NAT2 variants in the Mexican population. Blood samples were collected predose and serially post-dose in an interval of 48 h. Hydralazine and valproate concentrations were determined by ultra-high performance liquid chromatography (UPLC) coupled to tandem mass spectroscopy (MS/MS).

RESULTS AND DISCUSSION

The AUC0-48 h and Cmax of hydralazine were almost identical (1410 ± 560 vs. 1446 ± 509 ng h/mL and 93·4 ± 16·7 vs. 112·5 ± 42·1 ng/mL) in both groups with NAT2 genotype-adjusted doses, whereas the multidose parameters of valproate were not significantly affected neither by the selection of the NAT2 genotype (AUC0-48 h 2064 ± 455 vs. 1896 ± 185 μg h/mL; Cmax 96·4 ± 21·1 vs. 88·8 ± 7·2 μg/mL, for the fast and slow acetylators, respectively) nor the co-administration of 83 or 182 mg of hydralazine.

WHAT IS NEW AND CONCLUSION

Comparable hydralazine exposures (differences in AUC0-inf of only 7%) were observed in this study with genetic selection of volunteers and concomitant dose adjustment. However, the conclusions have yet to be confirmed with a full-powered 2 × 2 crossover study.

In vivo rat model to study horizontal tumor progression

Most cancer deaths are due to metastases. Metastasis is an extraordinarily complex process by which cancer cells complete a sequential series of steps before they transform into a clinically detectable lesion. These steps typically include separation from the primary tumor, invasion through surrounding tissues and basement membranes, entry and survival in the circulation, lymphatic or peritoneal space, and arrest in a distant target organ and the formation of secondary tumors in distant organs.While proposed or accepted models and mechanisms of metastatic progression, have been demonstrated in experimental systems, none of them sufficiently explain all of the complexities associated with this process. These models can broadly be classified into two types, those occurring by vertical gene transfer (Darwinian) and those involving horizontal or lateral DNA transfer. Here, we describe an experimental system to study the metastatic process involving the horizontal transfer of circulating DNA.

Radiosensitization of cervical cancer cells with epigenetic drugs hydralazine and valproate

PURPOSE

To evaluate the radiosensitizing effects of the DNA methylation inhibitor hydralazine in combination with valproic acid, a histone deacetylase inhibitor in cervical cancer cells.

MATERIALS AND METHODS

Cell viability assays were performed in the SiHa cervical cancer cell line treated with hydralazine and valproic acid for five days with and without cisplatin. Cell irradiation was performed using teletherapy (1.25 MV).

RESULTS

Neither hydralazine, valproic acid or cisplatin as single agents increased the cytotoxicity from radiation, however, the combination of hydralazine with valproic acid at ten microM and one mM, respectively, did induce radiosensitization (p = 0.046). Interestingly, this effect was further increased with the triple combination of hydralazine, valproic acid, and cisplatin (p = 0.041), where cell viability decreased more than 50% as compared to radiation alone.

CONCLUSIONS

The present results demonstrate that epigenetic drugs increase the efficacy of cisplatin chemoradiation in cervical cancer cells.

Cancer progression mediated by horizontal gene transfer in an in vivo model

It is known that cancer progresses by vertical gene transfer, but this paradigm ignores that DNA circulates in higher organisms and that it is biologically active upon its uptake by recipient cells. Here we confirm previous observations on the ability of cell-free DNA to induce in vitro cell transformation and tumorigenesis by treating NIH3T3 recipient murine cells with serum of colon cancer patients and supernatant of SW480 human cancer cells. Cell transformation and tumorigenesis of recipient cells did not occur if serum and supernatants were depleted of DNA. It is also demonstrated that horizontal cancer progression mediated by circulating DNA occurs via its uptake by recipient cells in an in vivo model where immunocompetent rats subjected to colon carcinogenesis with 1,2-dimethylhydrazine had increased rate of colonic tumors when injected in the dorsum with human SW480 colon carcinoma cells as a source of circulating oncogenic DNA, which could be offset by treating these animals with DNAse I and proteases. Though the contribution of biologically active molecules other than DNA for this phenomenon to occur cannot be ruled out, our results support the fact that cancer cells emit into the circulation biologically active DNA to foster tumor progression. Further exploration of the horizontal tumor progression phenomenon mediated by circulating DNA is clearly needed to determine whether its manipulation could have a role in cancer therapy.

Epigenetic therapy with hydralazine and magnesium valproate reverses imatinib resistance in patients with chronic myeloid leukemia

The epigenetic drugs hydralazine and valproate were administered in a compassionate manner to 8 patients with chronic myeloid leukemia (CML) refractory to imatinib. Two patients had a complete hematologic response (25%),1 major cytogenetic response, 1 complete cytogenetic response (25% any cytogenetic response), and 3 (37.5%)stable disease. No grade 3 or 4 toxicity was observed. These results show the ability of epigenetic therapy to revert imatinib resistance.

BACKGROUND

Epigenetic alterations participate in the development of acquired resistance to imatinib, hence, the DNA methylation, and histone deacetylase inhibitors hydralazine and valproate, respectively, has the potential to overcome it.

PATIENT AND METHODS

A series of 8 patients with chronic myeloid leukemia (CML) refractory to imatinib mesylate with no access to second-generation tyrosine kinase inhibitors were treated with hydralazine and valproate in a compassionate manner. Clinical efficacy and safety of these drugs added to imatinib mesylate were evaluated.

RESULTS

Two patients were in the blast phase, 5 were in the accelerated phase, and 1 was in the chronic phase. All the patients continued with the same dose of imatinib that they had been receiving at the time of development of resistance, with a median dose of 600 mg daily (range, 400-800 mg). The median time from diagnosis of CML to the start of hydralazine and valproate was 53.6 months (range, 19-84 months). Two (25%) patients had a complete hematologic response, one (12.5%) had an major cytogenetic response, and one (12.5%) had a complete cytogenetic response. Three (37.5%) patients had stable disease, and only one (12.5%) patient failed to respond. At a median follow-up time of 18 months (range, 3-18 months), the median survival had not been reached, and the projected overall survival was 63%. All the patients had mild neurologic toxicity, including distal tremor and somnolence. No grade 3 or 4 toxicity was observed.

CONCLUSIONS

Our results suggest that the epigenetic drugs hydralazine and valproate revert the resistance to imatinib in patients with CML.

Upregulation of NKG2D ligands and enhanced natural killer cell cytotoxicity by hydralazine and valproate

Natural killer cells play a role in the immune antitumor response by recognizing and eliminating tumor cells through the engagement of NKG2D receptors with their ligands on target cells. This work aimed to investigate whether epigenetic drugs are able to increase MICA and MICB expression as well as NK cell cytotoxicity. Prostate, colon, breast and cervical cancer cell lines were analyzed for the expression of MICA and MICB at the mRNA and protein levels by RT-PCR, Western blot, flow cytometry and ELISA. The activating mark H3K4m2 at the MICA and MICB promoters was investigated by ChIP assays. Cytotoxicity of NK cells against the target epithelial cancer cells was investigated with the CD107 cytotoxicity assay. The results show that hydralazine and valproic acid not only increase the expression of MICA and MICB ligands of target cells, but also reduce their shedding to the supernatant. This upregulation occurs at the transcriptional level as revealed by increase of the H3K4 activating mark at the promoter of MICA and MICB genes. These effects are paralleled by increased cytotoxicity of NK cells, which was attenuated at different degrees by using blocking antibodies against the NKG2D receptor and ligands. In conclusion, our results demonstrate the ability of hydralazine and valproate to increase the NK activity against epithelial cancer cell lines and suggest that these drugs could reduce the levels of soluble MICA and MICB helping in avoiding tumor-induced suppression of NK cytotoxicity against the tumor.

The epigenetic origin of aneuploidy

Theodore Boveri, eminent German pathologist, observed aneuploidy in cancer cells more than a century ago and suggested that cancer cells derived from a single progenitor cell that acquires the potential for uncontrolled continuous proliferation. Currently, it is well known that aneuploidy is observed in virtually all cancers. Gain and loss of chromosomal material in neoplastic cells is considered to be a process of diversification that leads to survival of the fittest clones. According to Darwin’s theory of evolution, the environment determines the grounds upon which selection takes place and the genetic characteristics necessary for better adaptation. This concept can be applied to the carcinogenesis process, connecting the ability of cancer cells to adapt to different environments and to resist chemotherapy, genomic instability being the driving force of tumor development and progression. What causes this genome instability? Mutations have been recognized for a long time as the major source of genome instability in cancer cells. Nevertheless, an alternative hypothesis suggests that aneuploidy is a primary cause of genome instability rather than solely a simple consequence of the malignant transformation process. Whether genome instability results from mutations or from aneuploidy is not a matter of discussion in this review. It is most likely both phenomena are intimately related; however, we will focus on the mechanisms involved in aneuploidy formation and more specifically on the epigenetic origin of aneuploid cells. Epigenetic inheritance is defined as cellular information—other than the DNA sequence itself—that is heritable during cell division. DNA methylation and histone modifications comprise two of the main epigenetic modifications that are important for many physiological and pathological conditions, including cancer. Aberrant DNA methylation is the most common molecular cancer-cell lesion, even more frequent than gene mutations; tumor suppressor gene silencing by CpG island promoter hypermethylation is perhaps the most frequent epigenetic modification in cancer cells. Epigenetic characteristics of cells may be modified by several factors including environmental exposure, certain nutrient deficiencies, radiation, etc. Some of these alterations have been correlated with the formation of aneuploid cells in vivo. A growing body of evidence suggests that aneuploidy is produced and caused by chromosomal instability. We propose and support in this manuscript that not only genetics but also epigenetics, contribute in a major fashion to aneuploid cell formation.

Phase III, Open-Label, Randomized Study Comparing Concurrent Gemcitabine Plus Cisplatin and Radiation Followed by Adjuvant Gemcitabine and Cisplatin Versus Concurrent Cisplatin and Radiation in Patients With Stage IIB to IVA Carcinoma of the Cervix

Purpose

To determine whether addition of gemcitabine to concurrent cisplatin chemoradiotherapy and as adjuvant chemotherapy with cisplatin improves progression-free survival (PFS) at 3 years compared with current standard of care in locally advanced cervical cancer.

Patients and Methods

Eligible chemotherapy- and radiotherapy-naive patients with stage IIB to IVA disease and Karnofsky performance score ≥ 70 were randomly assigned to arm A (cisplatin 40 mg/m2 and gemcitabine 125 mg/m2 weekly for 6 weeks with concurrent external-beam radiotherapy [XRT] 50.4 Gy in 28 fractions, followed by brachytherapy [BCT] 30 to 35 Gy in 96 hours, and then two adjuvant 21-day cycles of cisplatin, 50 mg/m2 on day 1, plus gemcitabine, 1,000 mg/m2 on days 1 and 8) or to arm B (cisplatin and concurrent XRT followed by BCT only; dosing same as for arm A).

Results

Between May 2002 and March 2004, 515 patients were enrolled (arm A, n = 259; arm B, n = 256). PFS at 3 years was significantly improved in arm A versus arm B (74.4% v 65.0%, respectively; P = .029), as were overall PFS (log-rank P = .0227; hazard ratio [HR], 0.68; 95% CI, 0.49 to 0.95), overall survival (log-rank P = .0224; HR, 0.68; 95% CI, 0.49 to 0.95), and time to progressive disease (log-rank P = .0012; HR, 0.54; 95% CI, 0.37 to 0.79). Grade 3 and 4 toxicities were more frequent in arm A than in arm B (86.5% v 46.3%, respectively; P < .001), including two deaths possibly related to treatment toxicity in arm A.

Conclusion

Gemcitabine plus cisplatin chemoradiotherapy followed by BCT and adjuvant gemcitabine/cisplatin chemotherapy improved survival outcomes with increased but clinically manageable toxicity when compared with standard treatment.

F18-FDG-PET/CT in the evaluation of patients with suspected recurrent or persistent locally advanced cervical carcinoma

BACKGROUND

Cervical cancer (CC) represents the second most common neoplasm and the third cause of death by cancer among women. Recurrent or persistent disease depends on the clinical stage, but can be as high as 70%. Positron emission tomography/computed tomography (PET/CT) is an image study that can detect increased glucose uptake in tumor tissues.

MATERIAL AND METHODS

PET/CT was performed in patients with confirmed CC, who had been previously treated, who developed suspected symptoms of recurrence or persistent disease with or without evidence of disease on a CT scan. Sensitivity, specificity, predictive values from PET/CT, and CT scan were evaluated.

RESULTS

Sixteen patients with a mean age of 47.2 years were included in the study from April 2007 to June 2008. Thirteen patients (81.2%) were symptomatic. PET/CT was positive in 14/16 (85.7%), of these, 12 True positive (TP) and two, False positive (FP); meanwhile another two cases were True negative (TN) (12.5%). Cervix, retroperitoneal, iliac, obturator, and mediastinal lymph nodes were the most common anatomic sites detected by PET/CT. Mean number of anatomic sites with high Fluoro-deoxy-D-glucose (FDG) uptake was two sites (range 1-7 sites). PET/CT and CT scan had 100 and 91.7% sensitivity, respectively. Specificity for both was 50%. Positive predictive value (PPV) was 85.4 and 84.6%, respectively. Negative predictive value (NPV) was 100 and 66%, respectively, and accuracy was 88 vs. 81%, respectively.

CONCLUSIONS

PET/CT has the capability for detecting recurrent or persistent cervical cancer; it detects increased metabolic activity mainly in primary site or lymph nodes. Further PET/CT evaluation is required to confirm the real impact of this study on the early detection of CC recurrence.

[The first Mexican consensus of endometrial cancer. Grupo de Investigación en Cáncer de Ovario y Tumores Ginecológicos de México]

INTRODUCTION

Endometrial cancer (EC) is the second most common gynecologic malignancy worldwide in the peri and postmenopausal period. Most often for the endometrioid variety. In early clinical stages long-term survival is greater than 80%, while in advanced stages it is less than 50%. In our country there is not a standard management between institutions. GICOM collaborative group under the auspice of different institutions have made the following consensus in order to make recommendations for the management of patients with this type of neoplasm.

MATERIAL AND METHODS

The following recommendations were made by independent professionals in the field of Gynecologic Oncology, questions and statements were based on a comprehensive and systematic review of literature. It took place in the context of a meeting of four days in which a debate was held. These statements are the conclusions reached by agreement of the participant members.

RESULTS

Screening should be performed women at high risk (diabetics, family history of inherited colon cancer, Lynch S. type II). Endometrial thickness in postmenopausal patients is best evaluated by transvaginal US, a thickness greater than or equal to 5 mm must be evaluated. Women taking tamoxifen should be monitored using this method. Abnormal bleeding in the usual main symptom, all post menopausal women with vaginal bleeding should be evaluated. Diagnosis is made by histerescopy-guided biopsy. Magnetic resonance is the best image method as preoperative evaluation. Frozen section evaluates histologic grade, myometrial invasion, cervical and adnexal involvement. Total abdominal hysterectomy, bilateral salpingo oophorectomy, pelvic and para-aortic lymphadenectomy should be performed except in endometrial histology grades 1 and 2, less than 50% invasion of the myometrium without evidence of disease out of the uterus. Omentectomy should be done in histologies other than endometriod. Surgery should be always performed by a Gynecologic Oncologist or Surgical Oncologist, laparoscopy is an alternative, especially in patients with hypertension and diabetes for being less morbid. Adjuvant treatment after surgery includes radiation therapy to the pelvis, brachytherapy, and chemotherapy. Patients with Stages III and IV should have surgery with intention to achieve optimal cytoreduction because of the impact on survival (51 m vs. 14 m), the treatment of recurrence can be with surgery depending on the pattern of relapse, systemic chemotherapy or hormonal therapy. Follow-up of patients is basically clinical in a regular basis.

CONCLUSIONS

Screening programme is only for high risk patients. Multidisciplinary treatment impacts on survival and local control of the disease, including surgery, radiation therapy and chemotherapy, hormonal treatment is reserved to selected cases of recurrence. This is the first attempt of a Mexican Collaborative Group in Gynecology to give recommendations is a special type of neoplasm.

A double-blind, placebo-controlled, randomized phase III trial of chemotherapy plus epigenetic therapy with hydralazine valproate for advanced cervical cancer. Preliminary results

The reversing of epigenetic aberrations using the inhibitors of DNA methylation and histone deacetylases may have therapeutic value in cervical cancer. This is a randomized phase III, placebo-controlled study of hydralazine and valproate (HV) added to cisplatin topotecan in advanced cervical cancer. Patients received hydralazine at 182 mg for rapid, or 83 mg for slow acetylators, and valproate at 30 mg/kg, beginning a week before chemotherapy and continued until disease progression. Response, toxicity, and PFS were evaluated, and 36 patients (17 CT + HV and 19 CT + PLA) were included. The median number of cycles was 6. There were four PRs to CT + HV and one in CT + PLA. Stable disease in five (29%) and six (32%) patients, respectively, whereas eight (47%) and 12 (63%) showed progression (P = 0.27). At a median follow-up time of 7 months (1-22), the median PFS is 6 months for CT + PLA and 10 months for CT + HV (P = 0.0384, two tailed). Although preliminary, this study represents the first randomized clinical trial to demonstrate a significant advantage in progression-free survival for epigenetic therapy over one of the current standard combination chemotherapy in cervical cancer. Molecular correlates with response and survival from this trial are pending to analyze.

Pharmacotherapy options for locally advanced and advanced cervical cancer

Cervical cancer continues to be a significant health burden worldwide. Globally, the majority of cancers are locally advanced at diagnosis; hence, radiation remains the most frequently used therapeutic modality. Currently, the value of adding cisplatin or cisplatin-based chemotherapy to radiation for the treatment of locally advanced cervical cancer is strongly supported by randomized studies and meta-analyses. Nevertheless, despite these significant achievements, therapeutic results are far from optimal; thus, novel therapies need to be investigated. A recent, randomized, phase III trial has shown for the first time that combination chemotherapy with cisplatin and gemcitabine concurrently with radiation improves parameters of survival over cisplatin alone and establishes a new standard for the management of locally advanced cervical cancer. On the other hand, advanced disease, presenting either as an International Federation of Gynecology and Obstetrics (FIGO) stage IVB or as persistent or recurrent to primary therapy without local curative options, remains a devastating group of diseases with no options other than palliative chemotherapy. Recent results from the GOG (Gynecologic and Oncologic Group)-204 study demonstrate that cisplatin-doublets with paclitaxel, vinorelbine, gemcitabine or topotecan only produce small improvements in survival, although with different toxicity patterns; hence, patient-related factors are important when choosing any one of these regimens. The role of targeted therapies both in locally advanced and advanced disease is promising, but still at an investigational stage.

Epigenetic therapy and cisplatin chemoradiation in FIGO stage IIIB cervical cancer

INTRODUCTION

This trial aimed to evaluate the safety and efficacy of epigenetic therapy associated with cisplatin chemoradiation in FIGO Stage IIIB patients.

METHODS

Hydralazine containing either 182 mg for rapid-, or 83 mg for slow acetylators and magnesium valproate were administered at 30 mg/kg tid. Both drugs were taken until intracavitary therapy was finished. Pelvic external beam radiation and low-dose rate brachytherapy were administered at a total cumulative dose to point A of at least 85 Gy. Weekly cisplatin at 40 mg/m2 was delivered for six cycles.

RESULTS

Twenty-two patients were included and 18 (82%) patients completed treatment. Mean dose to point A was 84.6 + 2.2. Median number of cisplatin cycles was 5.5 (range, 1-6). Brachytherapy was delayed for technical reasons; the mean overall treatment time was 11.8 weeks. Grade 3 anemia, leucopenia, neutropenia, and thrombocytopenia were observed in 9%, 45%, 45%, and 9% of patients, respectively.

CONCLUSIONS

Hydralazine and valproate are well-tolerated and safe when administered with cisplatin chemoradiation. Unfortunately, the suboptimal administration of brachytherapy for technical reasons in this study, precluded assessing the efficacy of epigenetic therapy. However, the tolerability of this regimen administered concurrent to radiation needs to be further tested.

Identification of a novel germ-line mutation in the TP53 gene in a Mexican family with Li-Fraumeni syndrome

BACKGROUND

Germ-line mutations of the TP53 gene are known to cause Li-Fraumeni syndrome, an autosomal, dominantly inherited, high-penetrance cancer-predisposition syndrome characterized by the occurrence of a variety of cancers, mainly soft tissue sarcomas, adrenocortical carcinoma, leukemia, breast cancer, and brain tumors.

METHODS

Mutation analysis was based on Denaturing high performance liquid chromatography (DHPLC) screening of exons 2-11 of the TP53 gene, sequencing, and cloning of DNA obtained from peripheral blood lymphocytes.

RESULTS

We report herein on Li Fraumeni syndrome in a family whose members are carriers of a novel TP53 gene mutation at exon 4. The mutation comprises an insertion/duplication of seven nucleotides affecting codon 110 and generating a new nucleotide sequence and a premature stop codon at position 150. With this mutation, the p53 protein that should be translated lacks the majority of the DNA binding domain.

CONCLUSION

To our knowledge, this specific alteration has not been reported previously, but we believe it is the cause of the Li-Fraumeni syndrome in this family.