• by Bruce Carlson
  • September 26 2017

Malignant Mesothelioma: Another Job for Liquid Biopsy

Malignant Mesothelioma: Another Job for Liquid Biopsy

Mesothelioma is a challenging form of cancer because of late detection.   Despite advances in chemotherapy, radiation therapy and surgical management of LC and MM, the median survival remains less than 12 months.  How to change that has been a challenge, but new IVD technologies including liquid biopsy to detect biomarkers could help.  Early detection represents one of the most promising approaches to reducing the growing cancer burden by increasing chemotherapy treatment efficiency.   Malignant mesothelioma (MM), a malignancy linked to environment  or occupational, is increasing in incidence.   The diagnosis of mesothelioma is complex and is based on CT imaging and biopsy. Biopsy is the standard detection method but it is invasive and , cannot ensure the withdrawal of available and sufficient material to test.   Cytological analysis of pleural effusion is used in some cases, but it cannot distinguish MPM from benign cells, resulting in poor sensitivity.  Radologic detection is difficult because asbestos alters the patients histopathology. CT), which is costly, exposes patients to repeated high doses of radiation, and typically detects the malignancy at its advanced stage. 
Now with a biomarker discovery and test, there's a possibility for liquid biopsy technology to aid in early diagnosis.  .Liquid biopsy encompasses various diagnostic methods that use liquid, non-tissue specimens to provide information that can aid in the diagnosis, treatment and monitoring of cancer. Currently, tissue biopsies, along with imaging techniques, are the standard methods used in the diagnosis of solid cancers, but despite their widespread use, they have many limitations that open the door for other diagnostic technologies in oncology clinical settings.   Up to the present, several liquid biopsy diagnostic tests have been developed based on these technologies, and are currently commercialized for different types of cancers and applications.  Although in its early stages of development, Kalorama finds that the overall market is a dynamic and fast-developing one that is expected to evolve into a billion-dollar market by 2021. Kalorama covers Liquid Biopsy in its report Liquid Biopsy Markets

According to Mesothelioma.com, a blog published by the Mesothelioma Cancer Alliance, a study published in the journal Clinical Cancer Research shows promise.  It indicates that a blood test can speed the diagnosis of mesothelioma. Diagnosis is often delayed and usually requires surgery to obtain a tissue sample for examination, and early identification of mesothelioma has been shown to be one of the best ways to improve the effectiveness of treatment. As such, researchers have been working to develop new blood tests to diagnose mesothelioma, and this study shows that a blood protein commonly referred to as HMGB1 can be used with near 100% accuracy.

Our results are significant and clinically relevant as they provide the first biomarker of asbestos exposure and indicate that hyperacetylated HMGB1 is an accurate biomarker to differentiate malignant mesothelioma patients from individuals occupationally exposed to asbestos and unexposed controls.

Recently, a virtually non-invasive 'liquid biopsy' has emerged as source to characterize tumour heterogeneity.   Therefore, increasingly interest has been paid to circulating (cell-free) nucleic acids (cfDNA/cfmiRNAs) epigenetically modulated during cell transformation. Hypermethylation of tumour suppressor genes is frequently observed in cancers, and such epigenetic changes are potential markers for detecting and monitoring tumours. The same predictive biomarkers can be used as therapy targets.

 miRNA is an important area of focus because their alterations drive cancer development and progression.  miRNAs are distributed throughout the human genome, but the majority are at fragile sites that are frequently deleted in human cancers.       Panels of specific extracellular microRNAs are also emerging as a new tool for the secondary (selection of high-risk individuals to undergo screening) and tertiary (relapse) prevention of cancer, according to a 2016 American Journal of Cancer Research article (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4969398/)   Extra-cellular microRNAs have been detected in biological fluids and studied as possible cancer markers that can be detected by noninvasive procedures.  The panels may be used not only for early diagnosis but also to recognize different types of mesothelioma, which facilitates individualized therapy.   One study found that miR-126 exhibits the strongest correlation with malignant pleural mesothelioma; specifically, it is downregulated in patient sera [60,69]. miR-125 may distinguish mesothelioma patients from healthy individuals, but it is not downregulated in lung cancer patients. Therefore, it is also interesting as a marker to differentiate mesothelioma from lung cancer.