Differences in Pathology and Mutation Status Among Colorectal Cancer Patients Younger Than, Older Than, and of Screening Age.

BACKGROUND: Screening protocols for colorectal cancer are broadly recommended and effective in reducing mortality. However, populations from different age groups can harbor distinct pathologic and molecular profiles that can also be influenced by screening and polyp resection, especially in older ages. PATIENTS AND METHODS: We retrospectively analyzed tumors from stage IV colorectal cancer patients from a central pathology laboratory in Brazil that is a reference for mutational profiling countrywide. Patients were classified into age groups as follows: prescreening age (PrSA; < 45 years old), screening age (SA; 45-75 years old), and postscreening age (PoSA; > 75 years old). Every tumor was centrally reviewed by the pathologist. Groups were compared regarding clinicopathologic features, and the presence of RAS (renin-angiotensin system) and BRAF (v-Raf murine sarcoma viral oncogene homolog B) mutations. RESULTS: We included 1635 patients (215 PrSA, 1213 SA, 207 PoSA). There was no difference among groups regarding sidedness (P = .65) and KRAS (Kirsten rat sarcoma viral oncogene) mutations (P = .57). Stage IV disease at diagnosis (P = .04), the presence of a signet-ring cell component (P < .001), and poorly differentiated tumors (P = .02) were most common in young patients, while BRAF and NRAS (neuroblastoma RAS viral (v-ras) oncogene homolog) mutations were significantly more common among PoSA patients (P = .002 and .03, respectively). When divided by age decade, KRAS mutations seem to have a stable frequency among all ages, while the BRAF mutation rate increased with increasing age. CONCLUSION: BRAF mutations are more frequent among PoSA patients, and this seems to be a continuous trend. PrSA and PoSA patients seem to present a distinct profile from SA, including differences in molecular and pathologic aspects. These findings could impact the frequency of screening tests among different age groups.

Identification of target genes using gene expression profile of granulocytes from patients with chronic myeloid leukemia treated with tyrosine kinase inhibitors.

Differential gene expression analysis by suppression subtractive hybridization with correlation to the metabolic pathways involved in chronic myeloid leukemia (CML) may provide a new insight into the pathogenesis of CML. Among the overexpressed genes found in CML at diagnosis are SEPT5, RUNX1, MIER1, KPNA6 and FLT3, while PAN3, TOB1 and ITCH were decreased when compared to healthy volunteers. Some genes were identified and involved in CML for the first time, including TOB1, which showed a low expression in patients with CML during tyrosine kinase inhibitor treatment with no complete cytogenetic response. In agreement, reduced expression of TOB1 was also observed in resistant patients with CML compared to responsive patients. This might be related to the deregulation of apoptosis and the signaling pathway leading to resistance. Most of the identified genes were related to the regulation of nuclear factor κB (NF-κB), AKT, interferon and interleukin-4 (IL-4) in healthy cells. The results of this study combined with literature data show specific gene pathways that might be explored as markers to assess the evolution and prognosis of CML as well as identify new therapeutic targets.

Prevalência de talassemias e hemoglobinas variantes no estado de Goiás, Brasil / Prevalence of thalassemias and variant hemoglobins in the state of Goiás, Brazil

As anemias hereditárias, em especial as talassemias e hemoglobinas (Hb) variantes, são as mais comuns das alterações genéticas humanas; sua frequência na população brasileira é muito variável, dependendo dos grupos raciais formadores de cada região. O povoamento de Goiás, que teve início logo após o seu descobrimento, em 1726, motivado pela procura de ouro, foi composto principalmente por portugueses e escravos africanos, contexto que favoreceu a mestiçagem entre eles. Considerando que esses povos apresentam genes para as hemoglobinas anormais com frequências variadas, é esperado que se encontrem essas alterações genéticas na nossa população. O objetivo deste trabalho foi avaliar a a prevalência de talassemias e hemoglobinas variantes na população de Goiás. Para isso a casuística foi composta por 404 alunos participantes dos diversos cursos da Universidade Católica de Goiás (UCG), oriundos de 55 cidades do estado de Goiás. A prevalência de anemia hereditária por talassemias e hemoglobinas variantes em Goiás foi de 10,1 por cento, cuja ordem decrescente foi a seguinte: talassemia alfa heterozigótica (5,2 por cento), heterozigose para hemoglobina S (Hb AS) (2,2 por cento), heterozigose para hemoglobina C (Hb AC) (1 por cento), talassemia beta menor (0,7 por cento), associa��o entre talassemia alfa e heterozigose para Hb S (0,5 por cento), associação entre talassemia alfa e heterozigose para Hb C (0,3 por cento) e heterozigose para hemoglobina D (Hb AD) (0,3 por cento). Nenhum caso de homozigose foi encontrado no presente estudo. Este trabalho demonstrou a dispersão dos genes para Hb S, Hb C e Hb D, bem como de talassemias alfa e beta em uma população do estado de Goiás. Por essa razão, concluímos que é importante realizar programas com maior abrangência da população para estudo da epidemiologia das talassemias e hemoglobinas variantes no estado de Goiás.

The hereditary anemias, especially the thalassemies and hemoglobinopathies are the most common human genetic abnormalities. Their frequency in the Brazilian population is very variable depending on the racial groups typical of each region. The settlement of Goiás, that had its beginning after discovery in 1726 owing to the search for gold, was composed basically by Portuguese and African slaves, a context that favored the racial mixing among them. Considering that these groups present genes for abnormal hemoglobins with varied frequencies it is expected the finding of these genetic abnormalities within our population. The objective of this study was to evaluate the prevalence of thalassemies and variant hemoglobins in the population of Goiás. For this purpose the sample was composed by 404 participating students from several graduate courses of the Catholic University of Goiás originally from 55 cities of the state of Goiás. Laboratory tests were used taking into account the historical and demographic factors of the population. The prevalence of hereditary anemias by thalassemias and variant hemoglobins in Goiás was 10.1 percent, in which the decreasing order of these abnormalities was: alfa heterozygous thalassemy (5.2 percent); heterozygous hemoglobin S (Hb AS) (2.2 percent); heterozygous hemoglobin C (Hb AC) (1 percent); beta short thalassemy (0.7 percent); association between alpha thalassemy and heterozygous for hemoglobin S (0.5 percent); association between alpha thalassemy and heterozygous for hemoglobin C (0.3 percent); and heterozygous for hemoglobin D (0.3 percent). No homozygosity was found in the study group. This study demonstrates the need for large scale screening in human populations for epidemiological studies of the thalassemies and variant hemoglobins in the state of Goiás.