Identification of Novel FAM134B (JK1) Mutations in Oesophageal Squamous Cell Carcinoma

Abstract

Mutation of FAM134B (Family with Sequence Similarity 134, Member B) leading to loss of function of its encoded Golgi protein and has been reported induce apoptosis in neurological disorders. FAM134B mutation is still unexplored in cancer. Herein, we studied the DNA copy number variation and novel mutation sites of FAM134B in a large cohort of freshly collected oesophageal squamous cell carcinoma (ESCC) tissue samples. In ESCC tissues, 37% (38/102) showed increased FAM134B DNA copies whereas 35% (36/102) showed loss of FAM134B copies relative to matched non-cancer tissues. Novel mutations were detected in exons 4, 5, 7, 9 as well as introns 2, 4-8 of FAM134B via HRM (High-Resolution Melt) and Sanger sequencing analysis. Overall, thirty-seven FAM134B mutations were noted in which most (31/37) mutations were homozygous. FAM134B mutations were detected in all the cases with metastatic ESCC in the lymph node tested and in 14% (8/57) of the primary ESCC. Genetic alteration of FAM134B is a frequent event in the progression of ESCCs. These findings imply that mutation might be the major driving source of FAM134B genetic modulation in ESCCs.

Electrochemical Detection of FAM134B Mutations in Oesophageal Cancer Based on DNA‐Gold Affinity Interactions

“…FAM134B gene encodes a cis‐Golgi transmembrane protein that controls its expression patterns and regulates apoptosis in gastrointestinal carcinomas and neurological diseases ,,. More recently, we have reported 37 mutations in different exons of FAM134B gene and its significant DNA copy number variations in ESCC tissues .…”

“…Nine fresh frozen tissue samples from six metastatic lymph node tissues of ESCC patients and three matched non‐cancer oesophageal tissues (near the surgical section margin) were selected based on our previous findings on the detection of FAM134B mutations . Ethical approval has been acquired for the use of these samples from human research ethics committee of Griffith University (GU Ref No: MED/19/08/HREC).…”

“…DNA copy number normalization was performed according to the procedure of our previous study . To achieve the amplified amplicons of exon 4 of FAM134B gene, genomic DNA were amplified in a 10 μL reaction containing 5 μL of 2XSensiMix SYBR No‐ROX master mix (Bioline, London, UK), 1 μL of each 10 picomole/μL forward and reverse primer, 1 μL of genomic DNA at 20–50 ng/μL and 2 μL of nuclease‐free water.…”

“…Additionally, the accuracy of the electrochemical analysis was confirmed with our recently reported Sanger sequencing of FAM134B mutation . Sanger sequencing was performed and analyzed using a 3730xl Capillary sequencer (Applied Biosystems) under standardized cycling PCR conditions in the Australian Genome Research Facility (AGRF, Brisbane).…”

“…The FAM134B gene, one of the best in‐silico biomarkers for pluripotent stem cell , acts as an important player in the progression of oesophageal squamous cell carcinoma (ESCC) , colorectal cancer , and neurological diseases via regulating its expression patterns and regulating apoptosis. More recently, we have reported that FAM134B gene is frequently mutated in metastatic lymph node tissues and is correlated with tumour progression in ESCCs . Therefore, simple, inexpensive, accurate, and sensitive method for detecting FAM134B gene mutations in ESCC could be potentially useful in future targeted molecular therapies in this carcinoma.…”