microRNA (miRNA)

ARE REGULATORY 20-23 NUCLEOTIDE STRANDS OF RNA

 

MicroRNA (miRNA) are short strands of RNA (~22 nucleotides long) that are used in cells for post-transcriptional gene regulation [1]. miRNAs are stably expressed and detected in tissue and blood samples of cancer patients, and therefore acts as potential biomarkers reflective of various cellular events. An abnormal concentration of miRNAs has been shown to be associated with multiple classes of diseases such as cancer, heart disease, and neurological illnesses.

Currently, qPCR is used to quantify miRNA in human serum in research laboratories. However, qPCR is not used as a diagnostic tool because it is labor-intensive and requires purification of miRNAs from serum, which can be costly and results in a considerable amount of loss or damage to the miRNAs [1]. In addition, the time-consuming steps needed for both purification and qPCR make running two or more samples not feasible. The microarrays that have been developed to replace qPCR have not been able to provide reliable quantitative data [2]. As a result, even though miRNA characterization can be very effective in the clinical diagnosis, it is often not used.

By utilizing the power of biomolecular nanotechnology, UBC BIOMOD has aimed to improve the feasibility of miRNA detection in disease diagnosis. Specifically, in non-small cell lung cancer, there are four miRNAs (miR-193b, miR-301, miR-141, and miR-200b) that provide a distinct signature, which can be used for the early diagnosis of lung cancer [3]. In our project, we have targeted miR-193b but our system could be easily modified to target any other miRNA. Through combining DNA probes that are highly specific and sensitive to miRNA with rolling circle amplification and precise quantification techniques, UBC BIOMOD is developing an easy, quick, accessible, cheap assay for detecting miRNAs and diagnosing small cell lung cancer.

Sources: 

  1. Micro-RNA profiling: Approaches and Considerations
  2. MicroRNA assay methods: A review of current technologies
  3. A Novel Serum 4-microRNA Signature for Lung Cancer Detection

 

Lung cancer accounts for the most deaths of any type of cancer in the U.S. In 2017, it’s estimated that over 150,000 people will die from lung cancer. Non-small cell lung cancer (NSCLC) is the most aggressive type of lung cancer and it accounts for 15-20% of all lung cancer cases. The five-year survival rate for stage I non-small cell lung cancer is 49%, whereas for stage IV it is only at 1% [4]. Early detection plays a large role in prognosis and survival.

Generally, discomfort due to lung cancer starts in the late-stages, making annual screening an essential tool for detecting lung cancer early. Currently, screening methods are image-based: chest X-rays and low dose CT Scans (LDCT). Chest X-rays have failed to reduce mortality of lung cancer, while LDCT has shown promise by lowering mortality rates by 20% – it still is not able to detect lung cancer at its earliest stages. In addition, due to its subjective nature, it has led to overdiagnosis of lung cancer [5].

LDCT requires extremely expensive equipment and has a high cost associated with each test, limiting its feasibility, particularly around the world in less well-funded healthcare systems.

miRNAs provide a much better solution to the early detection of lung cancer as abnormal miRNA concentrations appear much earlier than irregularities that could be observed by LCDT. These irregularities are also very specific to the type of cancer that is progressing. Based on the concentrations of miRNA, the severity and aggressiveness of the tumors could also be characterized.

Sources: 

  1. Survival Rates (Cancer.org)
  2. Circulating miRNA in diagnosing SCLC (Journal of Molecular Medicine)

Non-Small Cell Lung Cancer

IS ONE OF THE MOST AGRESSIVE TYPES OF CANCER

5 Year Survival Rates

  • Stage I (Small Cell Lung Cancer) 49%
  • Stage II (Small Cell Lung Cancer) 35%
  • Stage III (Small Cell Lung Cancer) 14%
  • Stage IV (Small Cell Lung Cancer) 1%

Our Mission

UBC BIOMOD 2017 in a nutshell (or rather, a paragraph!)

UBC BIOMOD’s mission is to work on a project that would help people and have a positive impact on society. We used biomolecular nanotechnology to create a cost-effective assay that could be used for early detection of lung cancer through miRNA. By achieving this, we aim for a more successful prognosis and to ultimately increase rates of patient survival.