Investigation of Expression Profile of Placenta-specific 1 (PLAC1) in Acute Myeloid and Lymphoid Leukemias

Background

Placenta-specific 1 (PLAC1) is one of the cancer-testis-placenta antigens that has no expression in normal tissue except placenta trophoblast and testicular germ cells, but is overexpressed in a variety of solid tumors. There is a lack of studies on the expression of PLAC1 in leukemia. We investigated expression of PLAC1 in Acute Myeloid Leukemia (AML) and Acute Lymphoblastic Leukemia (ALL).

Methods

In this study, we investigated expression pattern of PLAC1 gene in peripheral blood and bone marrow mononuclear cells of newly-diagnosed patients with AML (n=31) and ALL (n=31) using quantitative real-time PCR. Normal subjects (n=17) were considered as control. The PLAC1 protein expression in the samples were also detected using western blotting.

Results

Our data demonstrated that PLAC1 transcripts had 2.7 and 2.9 fold-change increase in AML and ALL, respectively, compared to normal samples. PLAC1 transcript expression was totally negative in all studied normal subjects. Level of PLAC1 mRNA expression in ALL statistically increased compared to normal samples (p=0.038). However, relative mRNA expression of PLAC1 in AML was not significant in comparison to normal subjects (p=0.848). Furthermore, relative mRNA expression of PLAC1 in AML subtypes was not statistically significant (p=0.756). PLAC1 gene expression showed no difference in demographical clinical and para-clinical parameters. Western blotting confirmed expression of PLAC1 in the ALL and AML samples.

Conclusion

Considering PLAC1 expression profile in acute leukemia, PLAC1 could be a potential marker in leukemia which needs complementary studies in the future.

Proteome Analysis of Adult Acute Lymphoblastic Leukemia by Two-dimensional Blue Native/Sodium Dodecyl Sulfate Gel Electrophoresis

Background

Despite the significant progress in the treatment of Acute Lymphoblastic Leukemia (ALL) in children, it still remains as one of the most challenging malignancies in adults. Identification of new biomarkers may improve the management of adult ALL. Proteins expressed on the cell surface can be considered as disease-associated biomarkers with potential for diagnosis and targeted therapies. Thus, membrane proteome studies give essential information about the disease-related biomarkers.

Methods

We applied 2-dimensional blue-native SDS-PAGE technique followed by MALDI-TOF/TOF-mass spectrometry to study the cell membrane proteome of peripheral blood mononuclear cells of adult B-ALL patients in comparison to that of the healthy controls.

Results

Sixty seven differentially expressed protein spots were detected, among them 52 proteins were found to be up-regulated but the other 15 proteins were down-regulated in B-ALL. Five differentially expressed proteins, involved in energy metabolism pathways, were detected in B-ALL patients compared to the healthy control group.

Conclusion

Differentially expressed proteins provide an insight into the molecular biology of B-ALL. Further studies must be done to confirm our data to be considered as potential targets for detection and treatment of B-ALL.

Mirizzi syndrome with endoscopic ultrasound image

We describe a 66-year-old Caucasian man with type 1 Mirizzi syndrome diagnosed on endoscopic ultrasound. He presented with acute onset of jaundice, malaise, dark urine over 3-4 days, and was found to have obstructive jaundice on lab testing. CT scan of the abdomen showed intrahepatic biliary ductal dilation, a 1.5 cm common bile duct (CBD) above the pancreas, and possible stones in the CBD, but no masses. Endoscopic retrograde cholangiopancreatography (ERCP) by a community gastroenterologist failed to cannulate the CBD. At the University Center, type 1 Mirizzi syndrome was noted on endoscopic ultrasound with narrowing of the CBD with extrinsic compression from cystic duct stone. During repeat ERCP, the CBD could be cannulated over the pancreatic duct wire. A mid CBD narrowing, distal CBD stones, proximal CBD and extrahepatic duct dilation were noted, and biliary sphincterotomy was performed. A small stone in the distal CBD was removed with an extraction balloon. The cystic duct stone was moved with the biliary balloon into the CBD, mechanical basket lithotripsy was performed and stone fragments were delivered out with an extraction balloon. The patient was seen 7 weeks later in the clinic. Skin and scleral icterus had cleared up and he is scheduled for an elective cholecystectomy. Mirizzi syndrome refers to biliary obstruction resulting from impacted stone in the cystic duct or neck of the gallbladder and commonly presents with obstructive jaundice. Type 1 does not have cholecystocholedochal fistulas, but they present in types 2, 3 and 4. Surgery is the mainstay of therapy. Endoscopic treatment is effective and can also be used as a temporizing measure or definitive treatment in poor surgical risk candidates.

Raw shellfish consumption among renal disease patients. A risk factor for severe Vibrio vulnificus infection

BACKGROUND

Raw shellfish-associated Vibrio vulnificus septicemia, with a case-fatality rate of nearly 50%, occurs most commonly in immunocompromised patients or those with liver disease.

METHODS

Sixty patients with renal disease treated with hemodialysis at The George Washington University and awaiting renal transplantation completed an initial survey that assessed their raw shellfish eating habits and knowledge regarding the pathogen V. vulnificus. Patients were then given educational materials describing the risks of eating raw shellfish and, one month later, completed a second survey that assessed their knowledge retention and intent to eat or not eat raw shellfish in the future.

RESULTS

Sixty of 68 (88%) eligible patients completed the survey. Forty-eight percent of patients reported having eaten raw shellfish after being diagnosed with kidney disease, with the highest rates reported among subjects < or = 49 years old and subjects with more than a high school education. Prior to receiving the educational materials, no patient had heard of the pathogen V. vulnificus. Three quarters of patients reported never having been advised by a physician to avoid eating raw shellfish. One month after reading the educational materials, 75% of patients said they would refrain from eating raw shellfish in the future.

CONCLUSIONS

In view of their immunocompromised status, patients with end-stage renal disease should be counseled to abstain from eating raw shellfish.