Molecular targets and mechanisms of different aberrant alternative splicing in metastatic liver cancer

Metastasis remains a major challenge in the successful management of malignant diseases. The liver is a major site of metastatic disease and a leading cause of death from gastrointestinal malignancies such as colon, stomach, and pancreatic cancers, as well as melanoma, breast cancer, and sarcoma. As an important factor that influences the development of metastatic liver cancer, alternative splicing drives the diversity of RNA transcripts and protein subtypes, which may provide potential to broaden the target space. In particular, the dysfunction of splicing factors and abnormal expression of splicing variants are associated with the occurrence, progression, aggressiveness, and drug resistance of cancers caused by the selective splicing of specific genes. This review is the first to provide a detailed summary of the normal splicing process and alterations that occur during metastatic liver cancer. It will cover the role of alternative splicing in the mechanisms of metastatic liver cancer by examining splicing factor changes, abnormal splicing, and the contribution of hypoxia to these changes during metastasis.

[Research progress of non-alcoholic fatty liver disease in postmenopausal women]

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease with a risk of developing non-alcoholic hepatitis, cirrhosis and liver cancer. Postmenopausal women have an increased risk of developing metabolic diseases including NAFLD under the influence of various factors such as aging, endocrine and metabolic changes. This article summarizes the latest research of NAFLD in postmenopausal women to elaborate and analyze the epidemiological characteristics, correlation between NAFLD and postmenopause, possible pathogenesis as well as feasible prevention and treatment methods.

GENOME-WIDE MAPPING OF COPY NUMBER VARIATIONS IN COMMERCIAL HYBRID PIGS USING A HIGH-DENSITY SNP GENOTYPING ARRAY

Copy number variations (CNVs) are important forms of structural variation in human and animals and can be considered as a major genetic component of phenotypic diversity. Here we used the Illumina PorcineSNP60 BeadChip V2 and a DLY [Duroc x (Large White x Landrace)] commercial hybrid population to identify 272 CNVs belonging to 165 CNV regions (CNVRs), of which 66 are new. As CNVRs are specific to origin of population, our DLY-specific data is an important complementary to the existing CNV map in the pig genome. Eight CNVRs were selected. for validation by quantitative real-time PCR (qRT-PCR) and the accurate rate was high (87.25%). Gene function analysis suggested that a common CNVR may play an important role in multiple traits, including growth rate and carcass quality.

Spinocerebellar ataxia type 1 in China: molecular analysis and genotype-phenotype correlation in 5 families

BACKGROUND

Twelve genetic types of autosomal dominant hereditary ataxia have been recently identified and the genes responsible for most of them cloned. Molecular identification of the type of ataxia is important to determine the disease prevalence and its natural history in various populations.

OBJECTIVES

To perform molecular analysis of 75 Chinese families affected with spinocerebellar ataxia (SCA) and to evaluate the spectrum of mutations in these genes and the correlation between genotypes and phenotypes in Chinese patients.

SETTING

Neurogenetics Unit, China-Japan Friendship Hospital, Beijing, China.

METHODS

One hundred nine patients from 75 kindreds diagnosed as having autosomal dominant SCA, 16 patients with sporadic SCA or spastic paraplegia, 280 control chromosomes of the Chinese population, and 120 control chromosomes of the Sakha population were selected for this study. We conducted detailed mutational analysis by direct sequencing of polymerase chain reaction products amplified from genomic DNA.

RESULTS

Spinocerebellar ataxia type 1 (SCA1) was identified in 5 families with 12 studied patients. All affected family members were heterozygous for a CAG repeat expansion in the SCA1 gene containing 51 to 64 trinucleotide repeats. Normal alleles had 26 to 35 repeats. Spinocerebellar ataxia type 1 accounted for 7% of the studied Chinese families with ataxia. In addition, we determined the frequency of a single vs double CAT interruption in 120 control chromosomes of the Siberian Sakha population, which has the highest known prevalence of SCA1, and compared this with 280 control chromosomes from the Chinese populations. The results show that 64.7% of the Siberian normal alleles contain a single CAT interruption, whereas 92% of the Chinese had more than 1 interruption.

CONCLUSIONS

Spinocerebellar ataxia type 1 is responsible for 7% of affected families in the Chinese population. A correlation between the prevalence of SCA1 and the number of CAT interruptions in the trinucleotide chain suggests that a CAT-to-CAG substitution may have been the initial event contributing to the generation of expanded alleles and influencing relative prevalence of SCA1.

Spinocerebellar ataxia type 2 in China: molecular analysis and genotype-phenotype correlation in nine families

Sixteen patients from nine Chinese families with spinocerebellar ataxia type 2 (SCA2) were heterozygous for a CAG repeat expansion in the SCA2 gene containing 37 to 56 repeats, whereas the normal alleles carried 14 to 28 repeats. One or two CAA triplets within the CAG tract were seen in normal, but not in the expanded alleles. A strong inverse correlation was established between the number of CAG repeats and the age of disease onset. SCA2 accounted for 12% of the known Chinese families with spinocerebellar ataxia.

Machado-Joseph disease in four Chinese pedigrees: molecular analysis of 15 patients including two juvenile cases and clinical correlations

Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative disorder associated with the expansion of a (CAG)n array in the MJD1 gene. We analyzed the sizes of the (CAG)n array using DNA samples from 61 members of four Chinese MJD families and 18 Chinese normal control subjects and confirmed that the (CAG)n array in 15 MJD chromosomes was expanded to 72-86 repeat units. There were no subjects with (CAG)n array sizes intermediate between those of normal and MJD affected groups. Meanwhile, we found a significant negative correlation between the age of onset of symptoms and (CAG)n array size. The largest (CAG)n array of 86 repeat units was in the youngest patient, whose age of onset was 5 years. The intergenerational increase in number of CAG repeat units was associated with the clinical phenomenon of anticipation.

[Bone metabolism in pregnant women]

Serum ionized calcium, tartrate-resistant acid phosphatase (TR-ACP) and alkaline phosphatase (ALP) were measured in 80 pregnant women in different gestational weeks. The results showed that calcium level decreased significantly as the gestation week increased. Calcium level of umbilical cord was higher than that of third trimester of pregnancy. It indicated that calcium could be transported to fetus across the placenta against the concentration gradient. Both TR-ACP and ALP activity elevated as gestation week increased. This may suggest that the bone metabolism is very active in pregnant women.

Alpha-tocopherol content of breast milk in China

The alpha-tocopherol content of breast milk was measured in 71 mothers of preterm and term infants in China. The mean alpha-tocopherol content of breast milk was much lower than that reported in developed countries. alpha-Tocopherol levels were higher in colostrum and then decreased in the transition milk. Mothers of preterm infants produced colostrum with a slightly higher alpha-tocopherol content than that of the mothers of term infants. However, alpha-tocopherol levels in transition milk were similar in both groups.

Alpha-tocopherol concentrations in human milk from mothers of preterm and full-term infants in China

alpha-Tocopherol content in breast milk of 28 mothers who delivered preterm infants (preterm milk) and 43 mothers who delivered full-term infants (term milk) were measured. alpha-Tocopherol concentration in preterm milk did not differ significantly from that of term milk in the first 12 days of lactation (P > 0.05). There is a higher alpha-tocopherol concentration in the early colostrum, however, it decreases with the lactational days significantly. The investigation suggests that early breast-feeding would be beneficial to the improvement of vitamin E intake in neonates during the early life.

Effects of seasonality on blood ionized calcium in early neonatal periods

The levels of whole blood ionized calcium were observed in 200 healthy neonates in the first week of life in spring and in summer. Levels of blood ionized calcium were lower in neonates born in spring compared to those of neonates born in summer. The levels of blood ionized calcium in adults did not change in different seasons. This study suggested that seasonality had a significant effect on blood ionized calcium in early neonatal life.