Cancer epidemiology: researchers take a broader approach

Elizabeth Platz at 2012 Johns Hopkins Nano-Bio Symposium. Photo by Stephanie Fraley

“Where do cancer data even come from?” This was the question posed to Dr. Elizabeth Platz prior to the 2012 Johns Hopkins University Nano-Bio Symposium. Dr. Platz is the Martin D. Abeloff, MD Scholar in Cancer Prevention and director of the Cancer Epidemiology, Prevention, & Control Training Program at the Johns Hopkins Bloomberg School of Public Health. As a cancer epidemiologist, Platz studies the frequency, distribution, and causes of cancer using data collected by the National Cancer Institute. By looking at these data, epidemiologists hope to understand why cancer occurs and what might be done to prevent it. “Cancer mortality in the US is declining and has been for some time,” Platz said. “The question is why.”

Dr. Platz and other cancer epidemiologists work on answering this “why.” Platz explained that cancer epidemiologists hypothesize why cancer rates may be high in certain segments of the population, follow a cohort of at-risk patients to see if they develop disease, and then try to figure out if some risk factor could be partially responsible for the disease. By identifying risk factors, cancer epidemiologists can influence public policy and promote preventative action.

Increasingly, cancer epidemiologists are working with researchers trying to answer basic science questions. An example of Dr. Platz’s recent interdisciplinary work involves finding tissue-based markers for prostate cancer, which could inform diagnoses and treatment decisions made by clinicians. One potential marker the researchers found is telomere length. Telomeres are repeated units on the ends of all chromosomes. Platz and her team of collaborators at Johns Hopkins showed that variability in tumor cell telomere length gave a 40-times greater risk for recurrence when compared with low telomere length variability. In the future, telomere length may be quantified following removal of a patient’s primary tumor before deciding on the next course of treatment.

Dr. Platz finished her talk by discussing the importance of having scientists in the nanobiotechnology fields work with cancer epidemiologists. Nanobiotechnology could greatly help epidemiologists measure exposure to environmental toxins and handle large amounts of data, allowing the epidemiologists to better make and test hypotheses about why cancer occurs. Future collaborations have the potential to drastically improve cancer care and patient survival rates.

Story by Colin Paul, a Ph.D. student in the Department of Chemical and Biomolecular Engineering at Johns Hopkins with interests in microfabrication and cancer metastasis.

 

Four students honored at INBT research symposium

Spyros Stamatelos with INBT director Peter Searson. Photo by Mary Spiro

Four students were honored for their research efforts at Johns Hopkins Institute for NanoBioTechnology’s sixth annual symposium. A poster session with more than 75 research posters from every division of the university was held in the afternoon and four posters were selected for top honors.

A poster by Yu-Ja Huang, Justin Samorajski, Rachel Kreimer, Denis Wirtz and Peter Searson won first prize, and first author Huang was awarded the $200 gift card from Best Buy. Their poster was entitleThe Influence of Electric Field and Confinement on U-87 Glioblastoma Cells.

Jack Andraka describing his research at the INBT poster session. Photo by Mary Spiro

Taking second place was Anirudha Sing, Jianan Zhan and Jennifer Elisseeff with the poster Directed Stem Cell Differentiation Using PEG-alpha CD-derived biomaterials. First author Singh claimed the $100 Best Buy card.

A $50 Best Buy card was presented to Spyros Stamatelos who was first author with Eugene Kim, Arvind Pathak and Aleksander Popel on the poster Characterization of the Heterogeneity of Tumor Vasculature using Hemodynamic Modeling and High Resolution Imaging Implications for Drug Delivery.

Honorable mention was given to Jack Andraka, a high school research intern in the lab of Anirban Maitra who worked with Venugopal Chenna. Andraka’s poster, A Novel Paper Sensor for the Detection of Pancreatic Cancer, helped him win a free book from Springer.

The event was held  at the Johns Hopkins medical campus in the Owens Auditorium on May 4 with six faculty expert speakers and approximately 400 people in attendance.

Baby crystal discovery big step for nanoscience

How small can a chemical compound be and still retain the properties of that same compound in bulk? With computer models and laboratory experiments, researchers at Johns Hopkins University, collaborating with those at McNeese State University in Lake Charles, LA, and the University of Konstanz in Germany, have determined the smallest crystal configuration, or as they call it, a “baby crystal,” of lead sulfide.

Predicted dimensions of nano-blocks achieved by growing individual (PbS)32 baby crystals. STM images confirmed these dimensions. (Illustration courtesy Bowen Lab)

The team first determined the structure theoretically with computer modeling. They then proved their model experimentally in the laboratory by carefully depositing clusters of (PbS)32 onto a graphite surface, where the clusters could migrate together into larger nanoscale units.

“By using scanning tunneling microscope (STM) images to measure the dimensions of the resultant lead sulfide nano-blocks, we confirmed that (PbS)32 baby crystals had indeed stacked together as predicted by theory,” said Kit Bowen Jr., the E. Emmet Reid Professor in the Department of Chemistry at Johns Hopkins. Bowen worked on the project with, Howard Fairbrother, also a professor of chemistry. Both are affiliated faculty members of the Institute for NanoBioTechnology.

Bowen explained that the baby crystal needed just 32 units of lead sulfide to “exhibit the same structural coordination properties” of the same material at macroscale. Nanoblocks this small would have photovoltaic (solar power) applications.

“Determining the size of nano and sub-nano scale assemblies of atoms or molecules at which they first take-on recognizable properties of the same substance in the macroscopic world is an important goal in nanoscience,” Bowen said.

Their research can be found in the Journal of Chemical Physics and The Virtual Journal of Nanoscale Science & Technology. A Department of Energy grant funded this research.

 The Virtual Journal of Science & Technology

Bowen Lab

 

INBT obtains funding for engineering and science missions

Johns Hopkins students helped develop a bicycle-powered grain mill in Tanzania.

Engineering Missions for Graduate Student Education and Local Innovation

Applications are now being accepted for Global Engineering Innovation projects designed to give Johns Hopkins’ graduate students and select undergraduates an opportunity to investigate and tackle engineering challenges in the developing world. Undergraduate and graduate opportunities are available. Application deadline is April 5, 2013.

An information session on the Global Engineering Innovation program will be held on April 12  at 6 p.m. in  room G40 (ground floor conference room) in the New Engineering Building.

Johns Hopkins Institute for NanoBioTechnology has obtained funding to support three engineering mission teams composed of two to four students at a variety of international host sites. Teams will be mentored by an engineering faculty and a faculty member from the host site. Budgets, time lines and project plans will be developed by the team members with assistance by the host site faculty member.

To be eligible to apply, undergraduate and graduate students should be science or engineering majors (other majors will be considered if a fit is evident based on application material). Teams can be predefined by the students prior to applying but each team member must submit all application material. We will attempt to keep predefined teams together but the final decision will be made by the coordination committee (we will add or remove members if we feel a better team composition can be made).

To apply for this unique opportunity, send the following items to Ashanti Edwards at ashanti@jhu.edu.

  • Your resume including any outreach experience (domestic or international) and any foreign language capability (not required)
  • A brief (300 words max.) statement of your interest in Global Engineering Innovation
  • The name and contact information of at least one referee, preferably your faculty research advisor (or academic advisor for undergraduate students)

After teams, mentors and challenges are defined, the team or team leader will travel to the site to further evaluate challenge and design constraints. After return to Baltimore, the teams will meet to further research the challenge and brainstorm potential solutions. The JHU School for Advanced International Studies (SAIS) will be consulted so that students will be aware of the social and political atmosphere that may impact utilization and potential distribution of the engineering solutions. By the end of the first year, the students will have designed a working prototype. The teams will then travel to the Global Site with their working prototype to test solution feasibility and modify as needed. If successful, potential avenues of translation will be investigated with advisory board members with relevant experience.

 

Students talk cancer nanotech at Homewood March 21

Students affiliated with the Center of Cancer Nanotechnology Excellence (CCNE) and the Physical Sciences-Oncology Center (PS-OC) at Johns Hopkins University have organized a spring mini-symposium for March 21, 10 a.m. in the Hackerman Hall Auditorium at the Johns Hopkins University Homewood campus.

The student-run mini-symposiums aim to bring together researchers from across the campus affiliated with the PS-OC and CCNE. Graduate students training in these centers, both administered by Johns Hopkins Institute for NanoBioTechnology, work in various disciplines from physics to engineering to the basic biological sciences but with an emphasis on understanding cancer metastasis and developing methods for cancer diagnosis or therapy.

The invited speaker for the symposium is postdoctoral researcher Megan Ho of Duke University. Ho earned her PhD in mechanical engineering in the Wang lab in 2008. She is currently focused on developing microfluidic devices to investigate and control the fundamental reactions that form nanocomplexes for gene delivery. (10 a.m.)

Student apeakers, who will talk for 15 minutes, include:

  • Jane Chisholm (Justin Hanes lab/Ophthalmology): Cisplatin nanocomplexes for the local treatment of small cell lung cancer (10:20 a.m.)
  • Yunke Song (Jeff Wang Lab/Mechanical Engineering): Single Quantum Dot-Based Multiplexed Point Mutation Detection by Gap Ligase Chain Reaction (10:35 a.m.)
  • Andrew Wong (Peter Searson Lab/Materials Science and Engineering): Intravisation into an artificial blood vessel (10:50 a.m.)
  • Brian Keeley: (Jeff Wang Lab/Mechanical Engineering): Overcoming detection limitations of DNA methylation in plasma and serum of cancer patients through utilization of nanotechnology. (11:05 a.m.)
  • Sebastian Barretto (Sharon Gerecht Lab/Chemical and Biomolecular Engineering): Development of Hydrogel Microfibers to Study Angiogenesis (11:20 a.m.)

View the symposium flyer here. The mini-symposium is free and open to the entire Johns Hopkins University community. No RSVP is required, although seating is limited.

Johns Hopkins Physical Sciences-Oncology Center

Center of Cancer Nanotechnology Excellence

It’s a small world: Micro/nanotechnology in regenerative medicine and cancer

Sageeta Bhatia

Nanotechnology, regenerative medicine and cancer will be the topic of a special biomedical engineering seminar on March 6 at 3 p.m. in the Darner Conference Room, Ross Building, Room G007 at the Johns Hopkins School of Medicine. Speaker Sangeeta Bhatia, MD, PhD, director, of the Laboratory for Multiscale Regenerative Technologies at Massachusetts Institute of Technology will present “It’s a small world: Micro/Nanotechnology in Regenerative Medicine and Cancer. ” She will discuss the role of micro and nanotechnology for mimicking, monitoring and perturbing the tissue microenvironment.

“I will present our work on reconstructing normal liver microenvironments using microtechnology, biomaterials and induced pluripotent stem cells as well as our work on normalizing diseased cancer microenvironments using both inorganic and organic nano materials,” Bhatia noted in an announcement.  Bhatia is a professor of Health Sciences and Technology and professor of Electrical Engineering and Computer Science at MIT.

The talk is hosted by associate professor of Materials Science and Engineering and affiliated faculty member of the Institute for NanoBioTechnology Hai-Quan Mao. The event is free and open to the Johns Hopkins Community. Refreshments will be served.

 

 

Hopkins’ Herrera-Alonso earns NSF CAREER award

Margarita Herrera-Alonso

Margarita Herrera-Alonso, assistant professor in the Department of Materials Science and Engineering, has received the National Science Foundation CAREER Award. Herrera’s CAREER funding will support her goal of better understanding the structure and property relationships of new polymers inspired by nature.

Her research will enable these building blocks to be used in the context of other bio-inspired materials applications, such as drug carrier design. The CAREER Award recognizes the highest levels of excellence and promise in early-career scholars and teachers.

Herrera joined the Johns Hopkins University faculty in early 2010. She is an affiliated faculty member of Johns Hopkins Institute for NanoBioTechnology. She earned her PhD in polymer science and engineering from the University of Massachusetts at Amherst. Find out more about the projects the Herrera Group is working on at this website.

 

Johns Hopkins and UVa co-host 2-day imaging workshop

Learn about state-of-the-art imaging methods at the In Vivo Preclinical Imaging: an Introductory Workshop, March 20-21 at Johns Hopkins University’s School of Medicine Turner Auditorium. Co-hosted by Johns Hopkins University, the University of Virginia and the Society of Nuclear Medicine (SNM), this workshop will bring together gifted lecturers to cover the fundamentals of in vivo small animal imaging.

The workshop will cover an incredible breadth of material of interest and value to physicians, scientists (including postdoctoral fellows and graduate students) and scientific laboratory professionals interested in using molecular imaging for in vivo biomedical applications. Individuals with experience in small animal imaging as well as beginners are welcome. Participants learn the fundamentals of various small animal imaging modalities. A limited number of participants will also have the opportunity to register to attend a half-day, hands on workshop held on the afternoon of the second day, March 21. Registration for this unique opportunity is on first-come first-served, so don’t wait to register.

Speakers will address imaging modalities including MRI and MRS, PET, SPECT, optical imaging (bioluminescence & fluorescence imaging/tomography), ultrasound, x-ray CT, photoacoustic imaging and multimodality imaging. Speakers will also examine instrumentation, acquisition and reconstruction, MR/SPECT/PET imaging probes, targets and applications, small animal handling, techniques for imaging infectious disease models and data analysis.

More information about the workshop, including a full agenda of topics, registration and details about transportation and lodging can be found at the workshop website. www.snm.org/pci2012.

 

Hopkins to host colloid, surface science symposium

The Johns Hopkins University is hosting the 86th American Chemical Society’s Colloid and Surface Science Symposium in Baltimore, MD on June 10-13, 2012. The meeting includes 13 parallel sessions, a poster session, 28 invited speakers, and 28 session organizers. A new addition to this meeting is the Langmuir Student Awards presentation session with application details given on the conference website.

Abstract submission is now open and the deadline is February 7, 2012. Up-to-date information on the meeting can be found at the website: www.colloids2012.org.

For further details about this meeting please contact the symposium co-organizers Mike Bevan (mabevan@jhu.edu) and Joelle Frechette (jfrechette@jhu.edu). Bevan and Frechette are affiliated faculty members of Johns Hopkins Institute for NanoBioTechnology and members of the Department of Chemical and Biomolecular Engineering.

Download the symposium flyer here.

 

Engineered hydrogel helps grow new, scar-free skin

In early testing, this hydrogel, developed by Johns Hopkins researchers, helped improve healing in third-degree burns. Photo by Will Kirk/HomewoodPhoto.jhu.edu

Johns Hopkins researchers have developed a jelly-like material and wound treatment method that, in early experiments on skin damaged by severe burns, appeared to regenerate healthy, scar-free tissue.

In the Dec. 12-16 online Early Edition of Proceedings of the National Academy of Sciences, the researchers reported their promising results from mouse tissue tests. The new treatment has not yet been tested on human patients. But the researchers say the procedure, which promotes the formation of new blood vessels and skin, including hair follicles, could lead to greatly improved healing for injured soldiers, home fire victims and other people with third-degree burns.

The treatment involved a simple wound dressing that included a specially designed hydrogel—a water-based, three-dimensional framework of polymers. This material was developed by researchers at Johns Hopkins’ Whiting School of Engineering, working with clinicians at the Johns Hopkins Bayview Medical Center Burn Center and the Department of Pathology at the university’s School of Medicine.

Third-degree burns typically destroy the top layers of skin down to the muscle. They require complex medical care and leave behind ugly scarring. But in the journal article, the Johns Hopkins team reported that their hydrogel method yielded better results. “This treatment promoted the development of new blood vessels and the regeneration of complex layers of skin, including hair follicles and the glands that produce skin oil,” said Sharon Gerecht, an assistant professor of chemical and biomolecular engineering who was principal investigator on the study.

Guoming Sun, left, a postdoctoral fellow, and Sharon Gerecht, an assistant professor of chemical and biomolecular engineering, helped develop a hydrogel that improved burn healing in early experiments. Photo by Will Kirk/HomewoodPhoto.jhu.edu

Gerecht said the hydrogel could form the basis of an inexpensive burn wound treatment that works better than currently available clinical therapies, adding that it would be easy to manufacture on a large scale. Gerecht suggested that because the hydrogel contains no drugs or biological components to make it work, the Food and Drug Administration would most likely classify it as a device. Further animal testing is planned before trials on human patients begin. But Gerecht said, “It could be approved for clinical use after just a few years of testing.”

John Harmon, a professor of surgery at the Johns Hopkins School of Medicine and director of surgical research at Bayview, described the mouse study results as “absolutely remarkable. We got complete skin regeneration, which never happens in typical burn wound treatment.”

If the treatment succeeds in human patients, it could address a serious form of injury. Harmon, a coauthor of the PNAS journal article, pointed out that 100,000 third-degree burns are treated in U. S. burn centers like Bayview every year. A burn wound dressing using the new hydrogel could have enormous potential for use in applications beyond common burns, including treatment of diabetic patients with foot ulcers, Harmon said.

Guoming Sun, Gerecht’s Maryland Stem Cell Research Postdoctoral Fellow and lead author on the paper, has been working with these hydrogels for the last three years, developing ways to improve the growth of blood vessels, a process called angiogenesis. “Our goal was to induce the growth of functional new blood vessels within the hydrogel to treat wounds and ischemic disease, which reduces blood flow to organs like the heart,” Sun said. “These tests on burn injuries just proved its potential.”

Gerecht says the hydrogel is constructed in such a way that it allows tissue regeneration and blood vessel formation to occur very quickly. “Inflammatory cells are able to easily penetrate and degrade the hydrogel, enabling blood vessels to fill in and support wound healing and the growth of new tissue,” she said. For burns, the faster this process occurs, Gerecht added, the less there is a chance for scarring.

Originally, her team intended to load the gel with stem cells and infuse it with growth factors to trigger and direct the tissue development. Instead, they tested the gel alone. “We were surprised to see such complete regeneration in the absence of any added biological signals,” Gerecht said.

Sun added, “Complete skin regeneration is desired for various wound injuries. With further fine-tuning of these kinds of biomaterial frameworks, we may restore normal skin structures for other injuries such as skin ulcers.”

Gerecht and Harmon say they don’t fully understand how the hydrogel dressing is working. After it is applied, the tissue progresses through the various stages of wound repair, Gerecht said. After 21 days, the gel has been harmlessly absorbed, and the tissue continues to return to the appearance of normal skin.

The hydrogel is mainly made of water with dissolved dextran—a polysaccharide (sugar molecule chains). “It also could be that the physical structure of the hydrogel guides the repair,” Gerecht said. Harmon speculates that the hydrogel may recruit circulating bone marrow stem cells in the bloodstream. Stem cells are special cells that can grow into practically any sort of tissue if provided with the right chemical cue. “It’s possible the gel is somehow signaling the stem cells to become new skin and blood vessels,” Harmon said.

Additional co-authors of the study included Charles Steenbergen, a professor in the Department of Pathology; Karen Fox-Talbot, a senior research specialist from the Johns Hopkins School of Medicine; and physician researchers Xianjie Zhang, Raul Sebastian and Maura Reinblatt from the Department of Surgery and Hendrix Burn and Wound Lab. From the Whiting School’s Department of Chemical and Biomolecular Engineering, other co-authors were doctoral students Yu-I (Tom) Shen and Laura Dickinson, who is a Johns Hopkins Institute for NanoBioTechnology (INBT) National Science Foundation IGERT fellow. Gerecht is an affiliated faculty member of INBT.

The work was funded in part by the Maryland Stem Cell Research Fund Exploratory Grant and Postdoctoral Fellowship and the National Institutes of Health.

The Johns Hopkins Technology Transfer staff has filed a provisional patent application to protect the intellectual property involved in this project.

Related links:

Sharon Gerecht’s Lab

Johns Hopkins Burn Center

Johns Hopkins Institute for NanoBioTechnology

 

Story by Mary Spiro