Saturday, January 10, 2009

Gene Function 'Lost' In Melanoma And Glioblastoma

Gene Function 'Lost' In Melanoma And Glioblastoma
Main Category: Cancer / Oncology
Also Included In: Dermatology; Neurology / Neuroscience; Genetics
Article Date: 18 Dec 2008 - 0:00 PST

Researchers at Georgetown University Medical Center have found a gene they say is inactivated in two aggressive cancers - malignant melanoma, a form of skin cancer, and glioblastoma multiforme, a lethal brain tumor. They add that because this gene, known as PTPRD, has recently been found to be inactivated in several other cancers as well, their discovery suggests that PTPRD may play a tumor suppressor role in a wide variety of different cancers.

The findings are published in the December 15 issue of Cancer Research.

"Over the past decade several dozen tumor suppressor genes have been identified, but only a minority of them is important in causing many different tumor types. PTPRD seems to be one of these broad spectrum tumor suppressor genes," says the study's lead investigator, Todd Waldman, MD, PhD, an associate professor of oncology at Georgetown's Lombardi Comprehensive Cancer Center.

If the hypothesis is true - and Waldman and his team are now investigating loss of PTPRD in a number of additional cancers -then it may be possible to design a therapy that has wide applicability in oncology, he says.

"Most targeted cancer drugs today work by inhibiting gene products that are overactive in cancer cells. In this case, it is loss of the PTPRD gene that leads to cancer," Waldman says. "Therefore, we are trying to discover the molecules that PTPRD's protein controls, and then we plan to target these downstream molecules with a novel agent."

Waldman found that when the researchers restored production of the gene's protein in cancer cells that harbored PTPRD deletions or mutations, these tumors stopped growing and initiated a program of cell suicide.

The researchers also discovered PTPRD mutations in both the blood and in tumors of a patient with multiple different kinds of cancers. "This suggests that the gene could be responsible for an inherited predisposition to cancer," Waldman says

PTPRD produces a receptor protein tyrosine phosphatase that bisects the outer membrane of a cell. The part that protrudes outside the cell body is thought to be involved in helping cells stick to each other to form a tissue as well as in cell-to-cell communication. The part that juts into the cell is an enzyme that removes phosphates from other proteins - in other words, it changes the activity of proteins either by activating or deactivating them, Waldman says.

"In the absence of PTPRD, there are as yet unknown proteins floating around inside the cell with more phosphate residues than they should have, and it is a well known fact that the presence of these residues activates cellular growth pathways," he says. But it is not yet known which specific proteins PTPRD regulates, Waldman says.

Deletions of PTPRD in human cancer cells were first discovered in 2005, and since then, deletions or mutations of the gene have been discovered in several cancer types, including those of the colon and lung.

In this study, Waldman and his research team, which includes investigators from the National Cancer Institute, the University of Iowa and Duke University, used a laboratory technique known as copy number analysis to look for PTPRD in melanoma cell lines and in samples of human glioblastoma multiforme, the deadliest of brain cancers.

This technique uses a gene microarray that contains millions of probes that can stick to different regions of the human genome. The researchers purified DNA from tumors and then used the microarray chip to quantify genomic copy number. They found that PTPRD was deleted or mutated in 12 percent of melanoma tumors and in 14 percent of glioblastoma tumors examined. "That makes PTPRD one of the most commonly mutated genes discovered yet in melanoma," Waldman says.

"Before this study, no single tyrosine phosphatase was thought to play a generally important role as a tumor suppressor gene n multiple tumor types," Waldman says. "Now we have provided the first functional evidence that PTPRD is a tumor suppressor gene, and potentially an important one at that."

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Article adapted by Medical News Today from original press release.
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The study was supported by an intramural research grant from the Georgetown University School of Medicine. The authors have no financial interests to disclose.

If you read carefully you will find the words cell to cell communication.

WHERE DID YOU HEAR THAT BEFORE????

jimmy B

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Greetings to One and All

This Blog is dedicated My Brother Kenny B. who passed away in the late 1970's with Cancer before the Internet.

It was he, who showed me How to live and give back. He was wise beyond his years.



Kenny B




Jimmy and Dee

Carepage: Jimmybreitfeller
Jimmy Breitfeller


My Profile as of 2009

My photo
Last July (2005)I was riding my bicycle to work at the Eastman Kodak Research Labs about 3 miles from home. I was wearing a knapsack to carry my things to and from the labs. I started noticing an ache on my back. So I decide to go to the dermatologist. To make the long story short, it was cancer. I knew from my research that I would be needing adjuvant therapy. So I started communicating with Sloan Kettering, University of Pittsburgh Cancer Center, and a couple of others including the Wilmot Cancer Center at Strong. I realized that by telling my story, I might help someone else out there in a similar situation. So to all who are linked by diagnosis or by relation to someone with melanoma, I wish you well. Stay positive, read as much as you can (information helps to eliminate the fear associated with the unknown), and live for today, as no one can predict what tomorrow may bring. Jimmy B. posted 12/15/08

Disclaimer

The information contained within this Blog is not meant to replace the examination or advice of your Oncologist or Medical Team. The educational material that is covered here or Linked to, does not cover every detail of each disorder discussed.

Only your physician/Oncologist can make medical decisions and treatment plans that are appropriate for you. But, An Educated Consumer is a Smart consumer.

As Dr. Casey Culberson Said:

"The BEST melanoma patient is an ACTIVE PARTICIPANT in his or her treatment
(not a PASSIVE RECIPIENT)"

Melanoma and the “Magic Bullet” (Monoclonal Antibodies)

Just to let you know I posted the first draft of the Melanoma and the “Magic Bullet” (Monoclonal Antibodies). on Melanoma Missionary In the Shared File Section. you can download it for 19.95 (Only kidding) it is Free for the taking.


It is 33 pages long and may help you in your quest for the Yellow Brick Broad. Just to let you know it is only the first draft. Revisions are sure to come. I wanted to get it to the people that need it the most, the Melanoma Patients.

Preview:

So, where does Interluekin-2 (IL-2) come into play? According to Byung-Scok et al and recent reports, IL-2 is not needed for developmental CD4+ CD25+ Treg cells in the thymus but does play an important role in the maintenance and function in the peripheral.18 Peripheral is defines as secondary system outside the bone marrow and thymus. It entails the site of antigen, immune system interaction. IL-2 is required for the peripheral generation of Tregs based Abbas’s and colleagues research.19

IL-2 prevents the spontaneous apoptosis of the CD4+ CD25+ Treg cells. It has been reported that patients with multiple advance-stage tumors have elevated levels of Tregs within the tumor microenviroment.20 Interluekin-2 is the survival factor for CD4+ CD25+ Treg cells.21 If the addition of IL-2 is on or before the maximum propagation of the CD4+ T cells, the Tregs population can increase 5-fold in a 96 hour period based on certain growth mediums.

By controlling the addition of the endogenous IL-2, one has a knob to turn and can lead to the control of the expansion of the Tregs. When you combined this control with the anti-CTLA-4 blockage, you can shift the balance of the immune response.

Now here is the catch. The maintenance and function of the CD8+ T-cells require CD4+ cells which secrete IL-2. So we don’t want to deplete the CD4+ cells, we want to control the expansion of the Tregs which are a subset of the CD4+ cells. It has been postulated by some researchers that the Anti-CTLA-4 blockage also suppresses the Treg function in a different mechanism. By using IL-2 as the rate limiting factor, we can suppress the CD4+ CD25+ Treg cell expansion by controlling the concentration and timing of the Inerluekin-2 at the tumor microenvironment.


The Interluekin-2 plays another role in this Melanoma Maze. In a study by Janas et al, Il-2 increases the expressions of the perforin and granzyme A, B and C genes in the CD8+ T-cells. This increase expression causes the CD8+ T-cells to mature into Cytoxic T Lymphocytes (CTLs). The exogenous IL-2 is required for the granzyme proteins. As stated previously, CTLs have cytoplasmic granules that contain the proteins perforin and granzymes. A dozen or more perforin molecules insert themselves into the plasma membrane of target cells forming a pore that enables granzymes to enter the cell. Once in the tumor cell, these enzymes are able to breakup (lyse) the cell and destroy it. This is the beginning of the end for the cancer cells. The tumors begin to shrink and the rest is history,



On the other hand, prolong therapy with Il-2 can result in causing apoptotic death of the tumor- specific CD8+ T-cells.23

Clearly in a clinical setting, timing, dose, and exposure to these drugs play a major roll in the immunotherapy, and can have dramatic effects on the outcome.

All it takes is that one magic bullet to start the immune reaction..

https://app.box.com/shared/kjgr6dkztj

Melanoma And The Magic Bullet (Monoclonal Antibodies)

Public Service Announcement

A call for Melanoma Patients by Dr. Steven A Rosenberg

"We continue to see a high rate of clinical responses in our cell transfer immunotherapy treatments for patients with metastatic melanoma", Dr. Rosenberg said.

"We are actively seeking patients for these trials and any note of that on a patient-directed web site would be appreciated."

If you would like to apply for his trials, here is the website and information.

Dr. Rosenberg's information


Dr. Rosenberg's Clinical Trials


For the Warriors




The Melanoma Research Alliance has partnered with Bruce Springsteen, the E Street Band, and the Federici family to alleviate suffering and death from melanoma. Please view Bruce Springsteen’s public service announcement inspired by Danny Federici. Danny was the E Street Band’s organist and keyboard player. He died on April 17, 2008 at Memorial Sloan-Kettering Cancer Center in New York City after a three year battle with melanoma.


http://www.melanomaresearchalliance.org/news/PSA/

Source Fastcures blog



Join the Relay for Life!!!

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Dear Family and Friends,

I’ve decided to take a stand and fight back against cancer by participating in the American Cancer Society Relay For Life® event right here in my community! Please support me in this important cause by making a secure, tax-deductible donation online using the link below.

To donate on line now, click here to visit my personal page.
Jimmy B AKA Melanoma_Missionary

Relay For Life® is a life-changing event that brings together more than 3.5 million people worldwide to:

CELEBRATE the lives of those who have battled cancer. The strength of survivors inspires others to continue to fight.

REMEMBER loved ones lost to the disease. At Relay, people who have walked alongside people battling cancer can grieve and find healing.

FIGHT BACK. We Relay because we have been touched by cancer and desperately want to put an end to the disease.

Whatever you can give will help - it all adds up! I greatly appreciate your support and will keep you posted on my progress.

Keep the Fire Burning!!!

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Sincerely,

Jimmy Breitfeller
Turn off Music before you "Click to Play"
Signs of Melanoma Carcinoma Skin Cancer

How Skin Cancer Develops by "About.com : Dermatology"

Call for Patients with Unresectable Liver Metastases Due to Melanoma



Delcath Systems Granted Orphan-Drug Designations for Cutaneous and Ocular Melanoma


Delcath is actively enrolling patients in a Phase III clinical trial testing its proprietary drug delivery system, known as Percutaneous Hepatic Perfusion (“PHP”), with melphalan for the treatment of ocular and cutaneous melanoma metastatic to the liver.

This NCI-led trial is enrolling patients at leading cancer centers throughout the United States. Commenting on these orphan-drug designations, Richard L. Taney, President and CEO of Delcath, stated, “These favorable designations are important steps in our efforts to secure Delcath’s commercial position upon conclusion of our pivotal Phase III trial for metastatic melanoma. We remain steadfast in our commitment to become the leader in the regional treatment of liver cancers and we continue to enroll patients in this study, and advance our technology and the promise that it offers to patients with these deadly forms of melanoma and other cancers of the liver, all with limited treatment options.”

Orphan drug designation, when granted by the FDA’s Office of Orphan Products Development, allows for up to seven years of market exclusivity upon FDA approval, as well as clinical study incentives, study design assistance, waivers of certain FDA user fees, and potential tax credits.


Current Trial Centers


Phase I Study of Hepatic Arterial Melphalan Infusion and Hepatic Venous Hemofiltration Using
Percutaneously Placed Catheters in Patients With Unresectable Hepatic Malignancies



James F. Pingpank, Jr., MD, FACS
Associate Professor of Surgery
Division of Surgical Oncology
Suite 406, UPMC Cancer Pavillion
5150 Centre Avenue
Pittsburgh, PA 15232
412-692-2852 (Office)
412-692-2520 (Fax)
PingpankJF@UPMC.edu


Blog Archive

Call For Melanoma Patients!!!!

Call For Melanoma Patients!!!!

Dr. Rosenberg Has a New Clinical Trial.

Our latest treatment has a 72% objective response rate with 36% complete responses.

We are currently recruiting patients for our latest trial.

Is there some way to post this “Call for Patients” on the web site?

Steve Rosenberg

Dr. Rosenberg's Clinical Trials



(For a copy of the research paper.. see My Shared files)

The news headlines shown above for Melanoma / Skin Cancer are provided courtesy of Medical News Today.