METHODS: COVID-19 samples that tested positive by reverse transcription polymerase chain reaction and with cycle threshold values <30 were obtained throughout Malaysia. Sequencing of SARS-CoV-2 complete genomes was performed using Illumina, Oxford Nanopore, or Ion Torrent platforms. A total of 6163 SARS-CoV-2 complete genome sequences were generated over the surveillance period. All sequences were submitted to the Global Initiative on Sharing All Influenza Data database.
RESULTS: From June 2021 to January 2022, Malaysia experienced the fourth wave of COVID-19 dominated by the Delta variant of concern, including the original B.1.617.2 lineage and descendant AY lineages. The B.1.617.2 lineage was identified as the early dominant circulating strain throughout the country but over time, was displaced by AY.59 and AY.79 lineages in Peninsular (west) Malaysia, and the AY.23 lineage in east Malaysia. In December 2021, pilgrims returning from Saudi Arabia facilitated the introduction and spread of the BA.1 lineage (Omicron variant of concern) in the country.
CONCLUSION: The changing trends of circulating SARS-CoV-2 lineages were identified, with differences observed between west and east Malaysia. This initiative highlighted the importance of leveraging research expertise in the country to facilitate pandemic response and preparedness.
METHOD: Several methods were employed to assess the function of LOC285629 such as gene silencing, qPCR, proliferation assay, BrdU assay, transwell migration assay, ELISA and protein profiler.
RESULTS: Via in silico analyses, we identified significant downregulation of LOC285629, a novel lncRNA, across CRC stages. LOC285629 expression was significantly downregulated in advanced stages (Stage III and IV) compared to Stage I (Kruskal-Wallis Test; p = 0.0093). Further in-house validation showed that the expression of LOC285629 was upregulated in colorectal cancer tissues and cell lines compared to the normal counterparts, but was downregulated in advanced stages. By targeting LOC285629, the viability, proliferative abilities, invasiveness and resistance of colorectal cancer cells towards 5-fluorouracil were reduced. It was also discovered that LOC285629 may regulate cancer progression by targeting several different proteins, namely survivin, BCL-xL, progranulin, PDGF-AA, enolase 2 and p70S6 K.
CONCLUSION: Our findings suggest that LOC285629 may be further developed as a potential therapeutic target for CRC treatment.