Chromosomal imbalances are uncommon in chagasic megaesophagus

Antiproliferative effect and ultrastructural alterations induced by 5-O-methylembelin on Trypanosoma cruzi

BACKGROUND

Embelin (EMB), obtained from Oxalis erythrorhiza Gillies ex Hooker et Arnott (Oxalidaceae), was reported against Trypanosoma cruzi and Leishmania spp. Additionally, antiprotozoan activity against Plasmodium falciparum was reported for its methylated derivative (ME).

PURPOSE

To evaluate the potential anti-Trypanosoma cruzi activity of EMB, ME and 2,5-di-O-methylembelin (DME) and analyze the possible mechanism of action.

STUDY DESIGN/METHODS

EMB was isolated by a chromatographic method from the air-dried ground whole plant. To evaluate the effects of methylation, ME and DME were synthesized and tested against T. cruzi epimastigotes and trypomastigotes. The most active compound ME was evaluated against amastigotes. Ultrastructural alterations, ROS generation and the effect on mitochondrial activity of ME were measured.

RESULTS

Compounds inhibited the proliferation of epimastigotes. ME was also active against intracellular amastigotes. Mitochondrial alterations were observed by TEM. Additionally, ME modified the mitochondrial activity, and induced an increase in ROS levels. These evidences postulate the mitochondrion as a possible target of ME.

CONCLUSION

ME inhibited amastigotes proliferation, thus being a potential lead compound for the treatment of Chagas' disease.

Presence of microsatellite instability in esophageal squamous cell carcinoma associated with chagasic megaesophagus

AIM

The molecular pathogenesis of esophageal squamous cell carcinoma (ESCC) has been increasingly studied, but there is no report on the role of MSI in ESCC development associated with chagasic megaesophagus (CM).Results/methodology: In four ESCC/CM (4/19) we found microsatellite instability (MSI) alterations (21.1%), being three MSI-L (15.8%) and one MSI-H (5.3%). Four out of 35 ESCC cases showed MSI-L (11.4%) and only one out of 26 CM cases presented MSI-L (3.9%). The MSI-H was observed in an ESCC/CM patient that presents lack of MSH6 immunostaining corroborating deficiency in MMR pathway. Interestingly, the MSI-H ESCC/CM case also presented a deletion the HSP110 poly(T)17 gene.

DISCUSSION/CONCLUSION

Taking together, we concluded that MSI is a rare event in esophageal squamous cell carcinoma, but can be associated with CM.

Mutational profile of TP53 in esophageal squamous cell carcinoma associated with chagasic megaesophagus

Chaga's disease is an important communicable neglected disease that is gaining wider attention due to its increasing incidence worldwide. Achalasia due to chagasic megaesophagus (CM), a complication of this disease, is a known-yet, poorly understood-etiological factor for esophageal squamous cell carcinoma (ESCC) development. In this study, we aimed to perform the analysis of TP53 mutations in a series of Brazilian patients with ESCC that developed in the context CM (ESCC/CM), and to compare with the TP53 mutation profile of patients with benign CM and patients with nonchagasic ESCC. Additionally, we intended to correlate the TP53 mutation results with patient's clinical pathological features. By polymerase chain reaction (PCR) followed by direct sequencing of the hotspot regions of TP53 (exon 5 to 8), we found that TP53 mutations were present in 40.6% (13/32) of the ESCC/CM group, 45% (18/40) of the nonchagasic ESCC group, and in only 3% (1/33) of the benign CM group. Missense mutations were the most common in the three groups, yet, the type and mutated exon mutation varied significantly among the groups. Clinically, the groups exhibited distinct features, with both cancer groups (ESCC and ESCC/CM) been significantly associated higher consumption of alcohol and tobacco, older age, worse Karnofsky performance status, poor outcome than the patients with benign CM. No significant association was found between TP53 mutation profile and clinical-pathological features in any of the three groups. We describe first the time the analysis of TP53 mutations in ESCC that developed in the context of CM, and the observed high frequency of mutations, suggest that TP53 also plays an important role in the tumorigenic process of this unexplored etiological condition.

Parasite Infection, Carcinogenesis and Human Malignancy

Cancer may be induced by many environmental and physiological conditions. Infections with viruses, bacteria and parasites have been recognized for years to be associated with human carcinogenicity. Here we review current concepts of carcinogenicity and its associations with parasitic infections. The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic while the protozoan Trypanosoma cruzi, the causing agent of Chagas disease, has a dual role in the development of cancer, including both carcinogenic and anticancer properties. Although malaria per se does not appear to be causative in carcinogenesis, it is strongly associated with the occurrence of endemic Burkitt lymphoma in areas holoendemic for malaria. The initiation of Plasmodium falciparum related endemic Burkitt lymphoma requires additional transforming events induced by the Epstein-Barr virus. Observations suggest that Strongyloides stercoralis may be a relevant co-factor in HTLV-1-related T cell lymphomas. This review provides an overview of the mechanisms of parasitic infection-induced carcinogenicity.

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The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic.

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Trypanosoma cruzi has a dual role in cancer development including both carcinogenic and anticancer properties.

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Initiation of Plasmodium falciparum related endemic Burkitt lymphoma requires additional transforming events induced by EBV.

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Strongyloides stercoralis may be a relevant co-factor in HTLV-1-related T cell lymphomas.

We searched MEDLINE database and PubMed for articles from 1970 through June 30, 2016. Search terms used in various combinations were “parasite infection”, “carcinogenesis”, “cancer”, “human malignancy”, “parasite and cancer”, “infection-associated cancer”, “parasite-associated cancer” “schistosomiasis”, “opisthorchiasis”, “malaria”, “Chagas disease”, and “strongyloidiasis”. Articles resulting from these searches and relevant references cited in those articles were selected based on their related topics and were reviewed. Abstracts and reports from meetings were also included. Articles published in English were included.

Biologic and genetics aspects of chagas disease at endemic areas

The etiologic agent of Chagas Disease is the Trypanosoma cruzi, transmitted through blood-sucking insect vectors of the Triatominae subfamily, representing one of the most serious public health concerns in Latin America. There are geographic variations in the prevalence of clinical forms and morbidity of Chagas disease, likely due to genetic variation of the T. cruzi and the host genetic and environmental features. Increasing evidence has supported that inflammatory cytokines and chemokines are responsible for the generation of the inflammatory infiltrate and tissue damage. Moreover, genetic polymorphisms, protein expression levels, and genomic imbalances are associated with disease progression. This paper discusses these key aspects. Large surveys were carried out in Brazil and served as baseline for definition of the control measures adopted. However, Chagas disease is still active, and aspects such as host-parasite interactions, genetic mechanisms of cellular interaction, genetic variability, and tropism need further investigations in the attempt to eradicate the disease.