UH Biochemist Works To Revolutionize Ovarian Cancer Treatment By Unleashing the Power of MicroRNAs & Nanotechnology

The day when an ovarian cancer patient can treat her tumor with a single, painless pill instead of a toxic drug cocktail is the ultimate goal of the pioneering research of a University of Houston (UH) scientist.  Preethi Gunaratnee, assistant professor in the department of biology and biochemistry, is studying a class of tiny genetic molecules known as microRNAs and pinpointing those that could unleash the body’s natural cancer-fighting agents.

The day when an ovarian cancer patient can treat her tumor with a single, painless pill instead of a toxic drug cocktail is the ultimate goal of the pioneering research of a University of Houston (UH) scientist.

Preethi Gunaratnee, Ph.D., Assistant Professor, Department of Biology & Biochemistry, University of Houston

Preethi Gunaratnee, assistant professor in the department of biology and biochemistry, is studying a class of tiny genetic molecules known as microRNAs and pinpointing those that could unleash the body’s natural cancer-fighting agents. Additionally, she is developing a novel method to effectively deliver this treatment to the targeted cells by using an unusual carrier – nanoparticles of gold – through the work of Lalithya Jayarathne, a postdoctoral researcher in Gunaratne’s lab.

Gunaratne’s potentially groundbreaking work in ovarian cancer has gained exceptional notice and momentum this year with a series of high-profile research grants. In October, her ovarian cancer project was awarded a $200,000 High Impact/High Risk grant from the Cancer Prevention and Research Institute of Texas (CPRIT), which oversees the state’s billion-dollar war on cancer. In November, she was approved for a $250,000 grant from Houston’s Cullen Foundation. Earlier this year, she was chosen a beneficiary of the Baylor College of Medicine Partnership Fund.

Each year, the Baylor partnership undertakes a major fundraising campaign for a specific health project. For 2010-11, the partnership is raising money to fund the collaborative ovarian cancer project of Gunaratne and Baylor researchers Matthew Anderson, M.D., Ph.D. and Martin Matzuk, M.D., Ph.D.

All this promising research has its origins in a revolution in genetic science that began just a few years ago. Attention has long centered on nucleic acids known as DNA, with little consideration given to its cousin RNA or to microRNAs, which were considered “genetic junk” that played no significant role in the human genome, Gunaratne said.

MicroRNA Expression (Rosetta Genomics)

That began to change earlier this decade as scientists discovered that microRNAs might actually be the hidden regulators that control the 30,000 genes in the human body by silencing gene expression. Gunaratne has been at the vanguard of this development. With its 2008 acquisition of a $1 million genome sequencer device – the Illumina Genome Analyzer – UH instantly became a major player in this cutting-edge research. This state-of-the-art machine can rapidly deconstruct and analyze millions of pages worth of genetic data and allowed Gunaratne’s lab to sequence hundreds of normal and diseased tissue samples.

Gunaratne set her sights on a variety of cancers, including ovarian tumors, pediatric neuroblastoma and multiple myeloma. Using the sequencer in collaboration with Baylor, Texas Children’s Cancer Center and the Lurie Cancer Center at Northwestern University, her team created a unique database documenting genome-wide patters of microRNA and gene expression across an array of human tissues and cancers. The ultimate goal is to connect specific microRNAs with the genes they regulate, individualized to attack specific genomes.

From this database, Gunaratne’s team was able to pinpoint a handful of microRNAs in the human body that can significantly or completely suppress the growth of cancer cells. One in particular, miR-31, discovered by Baylor collaborators and Gunaratne, shows promise as a potent tumor suppressor in ovarian cancer, glioblastoma, osteosarcoma and prostate cancer.

They discovered that miR-31 can specifically target and kill cancer cells that are deficient in p53, a crucial gene that guards the integrity of the genome and prevents cancer. More than half of all cancers and 90 percent of papillary serous tumors – the most common type of malignant ovarian cancer – are p53-deficient.

In cell cultures miR-31 suppressed and killed tumor cells deficient in p53, while sparing cells with a normal p53 gene. Since all non-cancerous cells in the body would be resistant to miR-31, it can fight tumors without the side effects associated with chemotherapy.

“Delivering these microRNAs into human patients is a much trickier proposition than working on cell cultures and has never been done,” Gunaratne said. “Other types of gene therapy have been delivered with modified viruses in clinical trials, but ongoing safety concerns will likely prevent its widespread use.”

However, Gunaratne believes gold, which is biocompatible and easily functionalized to carry hundreds of microRNAs on the surface, can act as an effective carrier of genetic molecules. In lab tests, gold nanoparticles containing miR-31 penetrated 90 percent of targeted cells within 20 minutes, killing cancer cells three times faster than microRNAs delivered through lentiviruses, which are traditionally used in carrying gene-based treatments to diseased cells.

The next step is to test these microRNA-conjugated gold particles on tumors in mice to see if they can be delivered orally or through injection to shrink the tumors. If all goes as planned, this potentially revolutionary ovarian cancer treatment could be ready for phase I clinical trials in humans at the end of the two-year CPRIT grant, Gunaratne said.

Ovarian cancer is the fifth deadliest cancer among women, with about 15,000 deaths annually in the United States. Thus far, in cancer treatment generally, genetic markers have been helpful in assessing cancer patients’ risk and channeling them into the most effective treatment options. If scientists like Gunaratne are successful, doctors will go beyond just observing and reacting to a cancer patient’s gene expression to actually changing it, activating the body’s natural tumor suppressants. This could make chemotherapy a thing of the past.

“Although ovarian tumors are the focus of this project, our microRNA research is applicable to other cancers and diseases, too,” Gunaratne said. “Because a single microRNA can regulate hundreds of genes across diverse signaling pathways, they provide an especially promising way to control the patterns of gene expression that cause disease.”

Gunaratne also is a co-investigator with Baylor researchers on two other CPRIT grants announced in October, totaling $2.5 million. In one they will test siRNA-conjugated gold particles as an anti-cancer agent with Baylor’s Dr. Larry Donehower, and in the other they will use next-generation sequencing to look at epigenetic signals in malignant blood-related cancers with Dr. Margaret Goodell.

This most recent round of CPRIT grant awards marks the first time UH has received a research grant from CPRIT. Previous awards were for training graduate students and for raising cancer awareness.

“All these awards, CPRIT included, underscore UH’s growing role in biomedical research and demonstrate we can compete with other research powerhouses both locally and nationally,” Gunaratne said.

About the University of Houston

The University of Houston is a comprehensive national research institution serving the globally competitive Houston and Gulf Coast Region by providing world-class faculty, experiential learning and strategic industry partnerships. UH serves more than 38,500 students in the nation’s fourth-largest city, located in the most ethnically and culturally diverse region of the country.

About the College of Natural Sciences and Mathematics

The UH College of Natural Sciences and Mathematics, with 181 ranked faculty and approximately 4,500 students, offers bachelor’s, master’s and doctoral degrees in the natural sciences, computational sciences and mathematics. Faculty members in the departments of biology and biochemistry, chemistry, computer science, earth and atmospheric sciences, mathematics and physics conduct internationally recognized research in collaboration with industry, Texas Medical Center institutions, NASA and others worldwide.

Source: UH Biochemist Works to Revolutionize Ovarian Cancer Treatment – Preethi Gunaratne Wins Key Grants to Unleash Body’s Natural Cancer-fighting Agents, News Release, University of Houston, December 21, 2010.

2 thoughts on “UH Biochemist Works To Revolutionize Ovarian Cancer Treatment By Unleashing the Power of MicroRNAs & Nanotechnology

  1. Hi Paul,

    my mum is suffering from ovarian cancer, she finished her surgery and chemo, and has relapsed after 11months.

    can you please help me in find out if there is any further trail for the above research.

    Regards,
    Krishna

    Like

    • Dear Krishna,

      It is good to hear from you again. Unfortunately, all of the information that we have regarding the use of miRNA 31 and gold nanoparticles is listed in the article. It is our understanding that this therapeutic drug is not being studied in clinical trials, and will not be tested in phase I trials for at least 24 months, if not more. If you click on Dr. Preethi Gunaratnee’s picture, you will be taken to her biography page. This page provides her contact information in the event that you have additional questions.

      The only other miRNA-based therapy that is currently being tested in a phase I clinical trial involving CALAA-01. This drug is being studied in connection with solid tumors. Calando Pharmaceuticals is the manufacturer of this drug.

      Again, I have performed a search for all open ovarian cancer clinical trials in India and Australia. To view a list of open clinical trials in India, click here. Please note that the Avastin (bevacizumab) phase III clinical trial is going to be conducted at the following Indian locations:

      Bangalore, India, 560017
      Bangalore, India, 560054
      Hyderabad, India, 6500034
      Jaipur, India, 302013
      Kochi, India, 682 304
      Mumbai, India, 400 012
      Pune, India, 41104

      The Avastin trial is not yet recruiting patients, but you may want to contact Hoffman-LaRoche or Genentech to determine when the trial will begin. The formal Roche clinical trial list can be found at http://www.roche-trials.com/trialDetailsGet.action?studyNumber=MO22923&diseaseCategoryId=72&byLocation=true (Protocol #MO22923).

      To view a list of open clinical trials in Australia, click here. If you mom is able and willing to travel to Australia, there are three clinical trials testing a new ovarian cancer drug referred to as “AMG 386.”

      Krishna, we hope this information is helpful. If you have any additional questions, please feel free to contact us.

      Best regards,

      Paul

      Like

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