The frequency of NRAS mutation in stool samples of Iranian colorectal cancers compared to Finnish patients

Background

Stools from colorectal cancer patients are noninvasive samples that could be used to compare the frequency of hotspot mutations between two different ethnic cohorts.

Materials and Methods

We collected stool samples from the Iranian cohort (52 patients and 49 controls) and the Finnish cohort (40 patients and 14 controls). Following stool DNA extraction, we used the AmpliSeq Colon and Lung Cancer panel to prepare DNA libraries before sequencing.

Results

The Iranian cohort exhibited 35 hotspot mutations in the BRAF, ERBB4, FBXW7, FGFR1, FGFR3, KRAS, MAP2K, MET, NRAS, PIK3C, SMAD4, and TP53 genes. In the Finnish cohort, 13 hotspot mutations were found in the AKT1, APC, KIT, KRAS, SMO, STK11, and TP53 genes. Mutations in NRAS and FGFR3 were observed only in the Iranian cohort, while APC mutations were exclusive for the Finnish cohort.

Conclusion

Genes involved in MAPK and PI3K-MAPK pathways showed a higher frequency of mutations in Iranian patients which may have therapeutic implications.

A Review of Heavy Metals Accumulation in Red Meat and Meat Products in the Middle East

The problem of food contamination is a matter of concern, which cancausehealthcomplications in consumers.Severalinternational organizations have created standard permissible limits for heavy metals in meat products. Livestock such as sheep, cattle, camels, and goats are the most important sources of protein meat in the Middle East (ME) countries. Contamination of meat products with heavy metals (HMs) may be a threat to human health. Various scattered studies have been conducted in the Middle East on the contamination of red meat and meat products with HMs however, a comprehensive review on this subject has not yet been published. This study aimed to investigate the status of HMs in both raw andprocessedtypes of meatin the ME. Theresultsof thisnarrativereviewrevealed that in many ME countries, contamination of red meat with HMs was excessive. Therefore, more monitoringoflivestockconditionsandred meat products consumed in some Middle East countries seems necessary.

Gut Microbiota and Host Gene Mutations in Colorectal Cancer Patients and Controls of Iranian and Finnish Origin

BACKGROUND/AIM

Gut microbiota plays an important role in colorectal cancer (CRC) and its composition in CRC patients can be influenced by ethnicity and tumour genomics. Herein, the aim was to study the possible associations of ethnicity and gene mutations with the gut microbiota in CRC patients.

MATERIALS AND METHODS

Bacterial composition in stool samples of 83 CRC patients and 60 controls from Iran and Finland was studied by 16S rRNA gene sequencing. The association of gut microbiota composition with CRC, host mutations in KRAS, NRAS and TP53, and ethnicity analysed.

RESULTS

Beta diversity analysis indicated significant differences between the Iranian and Finnish gut microbiota composition, in both controls and patients' groups. The Iranian controls had higher abundance of Prevotella and lower abundance of Bacteroides compared to the Finnish controls, while the Finnish patients had higher abundance of Clostridium compared to Iranian patients. Abundance of Ruminococcus was higher in patients compared to the controls. Higher abundances of Herbaspirillum, Catenibacterium and lower abundances of Barnesiella were associated with mutations in NRAS, TP53, and RAS respectively.

CONCLUSION

A possible link of host gene mutations with gut bacterial composition is suggested.

Single nucleotide polymorphism rs696 in miR449a binding site of NFKBIA gene is correlated with risk of colorectal cancer

AIM

In present study we have elucidated the role of 2758 A>G (rs696), in the recognition site of miR449a in the 3' UTR of NFKB inhibitor alpha (NFKBIA) gene, in development of sporadic colorectal cancer.

BACKGROUND

Colorectal cancer (CRC) is rated as second cause of cancer death. Genetic determinants are considered as driving forces in development of sporadic CRC. Single nucleotide polymorphisms (SNPs), are attributed as the main genetic factor in cancers susceptibility. MicroRNAs, are key players in post-translational gene regulation by binding to their specific recognition sequences located at 3' untranslated region (UTR) of mRNAs.

METHODS

A case-control study using 143 CRC patients and 137 noncancerous counterparts were undertaken in order to determine rs696 genotypes using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

There was a significant difference for the genotype frequencies of rs696 between patients and controls. The frequencies of GG, AG, AA genotypes in the control group were 38.7, 45.3, and 16.1 %, respectively, and the genotype frequencies in case group were 19.6, 40.6, and 39.9 %, respectively.

CONCLUSION

Our results suggest significant correlation between rs696 polymorphism and colorectal cancer risk.

The effect of short duration sperm exposure on development of preeclampsia in primigravid women

BACKGROUND

Preeclampsia is one of the most serious complications, and affecting about 3% of pregnancies. The aim of this study was to estimate the impact short duration of exposure to sperm on development of preeclampsia.

METHODS

The duration of sperm exposure with the biological father (cohabitation without barrier methods) <3, <6 months were evaluated among 120 primigravid women with preeclampsia and 120 women without preeclampsia in a case-control study.

RESULTS

The short duration of exposure to sperm was more common in women with preeclampsia compared with controls (29.2 versus 14.2 for <3 months, adjOR 2.6 (95% CI=1.32-5.13) and (45 versus 29.2 for <6 months, adjOR 2.4 (95% CI=1.35-4.32). Regardless of the contraceptive method, short duration of cohabitation was more common in preeclamptic group (14.2 versus 5.8 for <3 months, adjOR 3.38 (95% CI=1.28-8.92) and (29.7 versus 13.3 for <6 months, adjOR 2.64(95% CI=1.24-5.79).

CONCLUSION

It was concluded that short duration of exposure to sperm was more common in women with preeclampsia compared with controls.

Assessment of quality of life in menopausal periods: a population study in kashan, iran

BACKGROUND

Menopause is a physiological process in women's life. The aim of this study was to assess QOL and related factors among menopausal women in Kashan city in Iran.

METHODS

Seven hundred women aged 40-60 years were assessed using cluster sampling. Women with mental and physical problems or systemic diseases were excluded. Data were collected by standard questionnaire of quality of life in the menopause.

RESULTS

The mean menopausal age was 47.6±4.1 years. 55.6% of women had been postmenopausal for less than 5 years. The overall mean scores obtained for each domain was 2.82±1.64 for vasomotor, 2.71±1.2 for psychosocial, 2.46±0.99 for physical and 2.89±1.73 for sexual domains.

CONCLUSION

Age, working status, physical activity, educational level, duration of menopause, income satisfaction, marriage satisfaction and the number of children in those living with family had influence on quality of life in menopausal women.

Functionally null mutations in patients with the cblG-variant form of methionine synthase deficiency

Methionine synthase (MS) catalyses the methylation of homocysteine to methionine and requires the vitamin B12 derivative, methylcobalamin, as cofactor. We and others have recently cloned cDNAs for MS and described mutations associated with the cblG complementation group that correspond to MS deficiency. A subset of cblG, known as "cblG variant," shows no detectable MS activity and failure of [57Co]CN cobalamin to incorporate into MS in patient fibroblasts. We report the mutations responsible for three cblG-variant patients, two of them siblings, who presented with neonatal seizures, severe developmental delay, and elevated plasma homocysteine. Cell lines from all three patients were negative by northern blotting, though trace MS mRNA could be detected by means of phosphorimage analysis. Reverse transcriptase-PCR, SSCP, and nucleotide sequence analysis revealed four mutations. All were functionally null, creating either a frameshift with a downstream stop codon or an insert containing an internal stop codon. Of the two mutations found in the siblings, one of them, intervening sequence (IVS)-166A-->G, generates a cryptic donor splice site at position -166 of an intron beginning after Leu113, resulting in a 165-bp insertion of intronic sequence at junction 339/340. The second is a 2-bp deletion, 2112delTC. Mutations in the third patient include a G-->A substitution, well within the intron after Lys203, which results in intronic inserts of 128 or 78 bp in the mRNA. The second mutation is a 1-bp insertion, 3378insA. We conclude that the absence of MS protein in these cblG variants is due to mutations causing premature translation termination and consequent mRNA instability.

Characterization of the testis and epididymis in mouse models of human Tay Sachs and Sandhoff diseases and partial determination of accumulated gangliosides

Beta-hexosaminidase (Hex) is an essential lysosomal enzyme whose activity is higher in the epididymis than in other tissues. The enzyme is also present in sperm and has been postulated to be required for fertilization. To better understand the role of Hex in reproduction, we have examined the testes and epididymides of mouse models of human Tay Sachs and Sandhoff diseases, produced by targeted disruption of the Hexa (alpha-subunit) or Hexb (beta-subunit) genes, respectively, encoding the enzymes Hex A (structure, alphabeta) and Hex B (betabeta). Testis weight, morphology, and sperm counts were unaffected in Hex-deficient mice. In the epididymis of the Hex A-deficient Hexa-/- mice, there was a large increase in the size and number of lysosomes in the initial segment/intermediate zone. In Hexb-/- mice (Hex A and B-deficient), the epididymal defects were much more extensive and the cytoplasm of all cell types throughout the efferent ducts and epididymis was filled with pale, uncondensed, enlarged lysosomes. In contrast to the brain where GM2 ganglioside accumulates, both mutant mice accumulated two non-GM2 gangliosides in the epididymis. The major accumulated species was characterized by electrospray ionization tandem mass spectrometry. The Hexa-/- male mice were fertile; however, litter sizes were reduced. The Hexb-/- males were able to sire normal sized litters up to nine weeks of age and remained healthy until 16-20 weeks of age. The extensive abnormalities in the Hexb-/- mice, in contrast to region-specific effects in the Hexa-/-mice, indicate an important and novel role for the Hex B isozyme in the epididymis and a region-specific role for Hex A in the initial segment/intermediate zone. In contrast to other reports, our results indicate that Hex is not essential for fertilization in young adult male mice. To explain the extensive epididymal abnormalities in the Hexb-/- mice, we propose that substrates for Hex, such as testis-derived glycolipids, cannot be catabolized and accumulate in lysosomes, leading to epididymal dysfunction and abnormalities in the epididymal luminal environment that supports sperm maturation.

Cloning of the cDNA and gene encoding mouse lysosomal sialidase and correction of sialidase deficiency in human sialidosis and mouse SM/J fibroblasts

Lysosomal sialidase occurs in a multienzyme complex that also contains beta-galactosidase and cathepsin A. We previously cloned the human lysosomal sialidase cDNA and characterized mutations in human sialidosis patients. Here, we report the cloning and expression of the mouse lysosomal sialidase cDNA and gene. The 1.77 kb cDNA encodes an open reading frame of 408 amino acids which shows high homology to the human lysosomal sialidase (80%), the rat cytosolic sialidase (65%) and viral and bacterial sialidases (50-55%). The sialidase gene is approximately 4 kb long and contains six exons. The five introns range in size from 96 to 1200 bp. Northern blot analysis revealed high expression of multiple sialidase transcripts in kidney and epididymis, moderate levels in brain and spinal cord, and low levels in adrenal, heart, liver, lung and spleen. Transient expression of the cDNA clone in sialidase-deficient SM/J mouse fibroblasts and human sialidosis fibroblasts restored normal levels of sialidase activities in both cell types. Immunocytochemically expressed sialidase co-localized with a lysosomal marker, LAMP2, confirming its lysosomal nature. Since sialidase activity requires its association with beta-galactosidase and cathepsin A, the expression of mouse sialidase within human sialidosis cells underlines the structural similarity between mouse and human enzymes and suggests that the mechanism for complex formation and function is highly conserved.

Expression and characterization of Aplysia protein kinase C: a negative regulatory role for the E region

The Aplysia nervous system contains two phorbol ester-activated protein kinase C isoforms, the Ca(2+)-activated Apl I and the Ca(2+)-independent Apl II. Short-term applications of the facilitatory transmitter serotonin (5-HT) activates Apl I, but not Apl II. In contrast, Apl II, but not Apl I, can form an autonomous kinase. To investigate the biochemical characteristics of the Aplysia kinases that might underlie their differential activation, we expressed Apl I, Apl II, and two derivatives of Apl II with deletions in the amino-terminal 150 amino acid E region in insect cells using the baculovirus system. Similar to nervous system extracts, expressed Apl II has more autonomous activity than Apl I. Removal of the E region lowered the amount of phosphatidylserine required for activation of Apl II, but did not remove the autonomous kinase activity. In addition, phosphatidylserine vesicles could sediment fusion proteins containing the E region, consistent with a role for the E region in lipid interactions. A partial deletion of the E region modifies activation of Apl II by phorbol esters and oleic acid, suggesting that in the intact enzyme the E region interacts with the phorbol ester-binding domain of the kinase. These results introduce a model whereby the E region acts as a negative regulator of Apl II activation and suggest that this inhibition may explain the inability of short-term applications of 5-HT to activate Apl II.