Showing posts with label cancer. Show all posts
Showing posts with label cancer. Show all posts

Thursday, March 15, 2018

What’s Epstein-Barr virus got to do with cancer?

I am a history buff, when it comes to medicine; I am naturally fascinated by the history of medicine, having a penchant of wanting to know how things came into being in medicine.

The story of Epstein-Barr virus (EBV) infectious mononucleosis is a good example.  Recently a friend as me about a relationship between mononucleosis and some sort of lymphoma.  I have to tell a story (which is history) to answer this question.

First a few facts:

  • Infectious mononucleosis is transmitted by EB virus.
  • Burkitt lymphoma is caused by EB virus, mostly in Africa.
  • Nasopharyngeal cancer (鼻咽癌)is caused by EB virus, mostly in China,Taiwan
  • Some of the stomach cancers are caused by EB virus.
  • Mononucleosis may lead to Hodgkin’s lymphoma.
From above facts, one can see EB virus can cause seemingly harmless mononucleosis, but may cause various cancers, including lymphoma.  It should come no surprise that it has been observed that mononucleosis may lead to Hodgkin’s lymphoma.

Dr. Denis Burkitt
The British surgeon (Dr. Denis Burkitt) served in Africa during WWII and he stayed to do missionary medical practice in Uganda after the war.  He observed that many young children were stricken with an aggressive tumor/cancer, and the distribution seemed to be corresponded to the rainy areas with a high year-round temperature.  He suspected it could be caused by some sort of viral infection.  He first reported in the British Journal of Surgery in 1958, the tumor now bears his name.

On March 22, 1961 Dr. Burkitt returned to England and gave a talk about his findings in Africa at a medical school in London, Dr. Michael Anthong Epstein was among the audience.  After the talk Dr. Epstein asked Dr. Burkitt to send him the tumor samples so he could do further research. 

Dr. Michael Anthony Epstein
Dr. Epstein has worked on Rous sarcoma virus.  Dr. Rous was the first one to discover a virus (now bears his name) can cause cancer in chicken, whereas EBV was the first virus known to cause cancer in human.  Dr. Rous was in his 80s when he was awarded a Nobel Prize in 1966, 40 years after his discovery.

Dr. Yvonne Barr joined Dr. Epstein in her PhD study.  There are numerous others, including several distinguished American virologists, made contribution in establishing EBV as the culprit in causing Burkitt lymphoma; an oncogene was also identified.  The intriguing course of discovery is beyond the scope of this writing.

Dr. Yvonne Barr
The virus was christened as Epstein-Barr virus in 1965.  The historical paper was published in Lancet (3/28/1964) with a title of “Virus particles in cultured lymphoblasts from Burkitt Lymphoma”.  Actually, Dr Burt Achong was also the co-author, but, poor Dr Achong, his name was somehow dropped at the naming of the virus and forgotten, except by a history buff like me. Dr Achong was a pathologist, using electron microscope to identify the virus.

There is an article in New England Journal of Medicine (NEJM) with a title of Hodgkin's lymphoma after infectious mononucleosis, in which it states there is casual connection between mononucleosis and Hodgkin’s lymphoma.

The evidence is that 40-50% of the Reed-Sternberg cells (the hallmark of Hodgkin’s lymphoma, 我看連退休或生銹的婦產科醫師都還記得) contain Epstein-Barr virus antigen.  And those patients did have history of mononucleosis.  The median interval between getting mononucleosis and the onset of Hodgkin’s lymphoma is only 4.1 years.

Dr. Burt Achong
Fortunately in this report among the 38,000 patients with mononucleosis, only 29 cases of Hodgkin’s lymphoma discovered.  Still some uncertainty present, as only one third of the adolescents with Hodgkin’s lymphoma with Reed-Sternberg cells containing EBV; so there is still much we don't know.

It is regrettable that none of these four British doctor-scientists was honored with Lasker awards ("American Nobel"), I think this an oversight.

EBV is also implicated in causing chronic fatigue syndrome; that calls for another post.




Sunday, November 5, 2017

The basis of cancer is genetic, using hepatitis B virus to illustrate the case

The main theme of this post is to say “the basis of cancer is genetic; the cancerous state is maintained by genes.”

The difference of germ cell mutation and somatic cell mutation  
Speaking of ‘genetic’, many automatically relate that it comes from parents and will pass along to children.  But, that is not the case.  There are two main types of cells: germ cells and somatic cells.  Germ cells are sex cells (gametes) that include sperms and eggs.  Each gamete contains one set of chromosomes (23).  When a boy (sperm) meets a girl (egg); they unite to form zygote (contains 2 sets of chromosomes or 46) which is the very beginning of an embryo.

Thus gamete (either sperm or egg) mutation can pass along to offspring, such as sickle cell anemia, cystic fibrosis or color blindness. Somatic (body) cells mutation will not pass along to offspring, but may cause cancer.

The basis of cancer is genetic                      
One needs to grasp two concepts to understand the story of why the basis of cancer is genetic:                              
(1)  Virus infection may lead to cancer; virus does it by ‘manipulating’ our genes.                                                 
(2)  Mutation of our genes (caused by virus or by chemical agents or radiation) leads to cancer.

Renato Dulbecco first demonstrated a viral infection may lead to cancer 
Dr. Renato Dulbecco
I wrote an obituary of Renato Dulbecco in February 2012 when he died, I called it “Remembrance (which is the obituary for Wall Street Journal): Renato Dulbecco”, to protest WSJ for not having a “Remembrance” for such a medical giant.

Dulbecco (at Caltech in 1960s) was the one demonstrated that DNA of a virus can integrate into the chromosomal DNA of the host cell, causing the uncontrolled cell growth, which is the genetic basis of cancer, and for which he was awarded a Nobel Prize in 1975, thus viral genes transform normal cells into cancer cells.

Michael Bishop and Harold Varmus (at UC Medical School at San Francisco in 1975) discovered the origin of so-called ‘cancer gene”, which is not of virus, but of our own gene.

Michael Bishop and Harold Varmus: The concept of proto-oncogene and oncogene 
Dr.Michael Bishop
If a given (human) gene is picked up and transduced/transformed by retrovirus (i.e. when cell is infected by retrovirus) into an oncogene, then this given human gene is called proto-oncogene.

In addition to virus being the culprit to transform a proto-oncogene to oncogene, certain chemical agents or radiation can cause a mutation of a proto-oncogene to become an oncogene, these chemical agents are called carcinogens, which are usually mutagens.

Michael Bishop and Harold Varmus worked on the Rous sarcoma virus (see the story later) in the early 1970s to make this discovery.  Even though the cancer is caused by virus, but the so-called ‘viral oncogenes’ are not truly viral at all but are of human genes in origin.  They discovered the retrovirus genomes are incorporated into the human gene and exploited to wreak havoc.  Michael Bishop and Harold Varmus were honored with Nobel Prizes in Medicine for this pivotal discovery in 1989.

Dr. Harold Varmus
The sequence of nucleotide in an oncogene can be different by only a single nucleotide from the sequence of the corresponding proto-oncogene, which is still normal and healthy.

Since the nucleotides sequence of a gene (DNA) is translated into the amino acid sequence of a protein the gene makes, so the sequence of amino acid of a oncogene protein [made by oncogene] can be different by only a single amino acid from the sequence of the corresponding proto-oncogene protein [made by proto-oncogene].
Dr. Peyton Rous

This is a good example that a single amino acid (among millions) goes astray can wreak havoc to cause cancer or sickle cell anemia.

Peyton Rous started it all 
Peyton Rous was honored with a Nobel Prize in Medicine in 1966, almost 40 years after he first discovered a virus (now bears his name) cause cancer in chicken.  This is the main reason why Michael Bishop and Harold Varmus picked Rous sarcoma virus to work.

A visit by Dr. Chih-Wen Lin whose article in the Journal of Hepatology prompted me to write this article article
Last week our friend, Dr. Chih-Wen Lin came to visit us from Taiwan.  有朋自遠方來,不亦樂乎.  His article (“Heavy alcohol consumption increases the incidence of hepatocellular carcinoma in hepatitis B virus-related cirrhosis”) in 2013 Journal of Hepatology (see photo) prompted my writing of this article.


Dr. Lin is the Director of the Department of Gastroenterology at E-DA Hospital/I-Shou University in Kao-Hsiung, Taiwan.  Their data showed that the 5-year cumulative incidence of hepatocellular carcinoma (HCC) is 10.7% in alcoholic cirrhotic patients, and the alcoholic cirrhotic patients with concomitant hepatitis B virus (HBV) infection have significantly higher incidence of HCC (36.8%) than those with HBV infection alone or alcoholism alone.

The focus of this post is not to discuss Dr. Lin’s article, but to show you that alcoholic cirrhosis without HBV infection can also lead to HCC (liver cancer).  In fact, cirrhosis from steatohepatitis (the most severe form of fatty liver), hemochromatosis or Wilson disease can also lead to HCC, less frequent though it may be.

The mechanisms of liver cancer-making in hepatitis B and hepatitis C are different                
Up to 90% of patients with hepatocellular carcinoma are known to have chronic liver disease and cirrhosis, hepatitis B infection may be a rare exception; HBV can cause HCC in the absence of cirrhosis, in contrast to HCV-related HCC which is found almost exclusively in patients with cirrhosis.

Hepatitis B virus (a DNA-containing virus) is able to integrate its DNA into the DNA of the host cells to transform it into oncogene, whereas hepatitis C virus (an RNA-containing virus) doesn’t have this ability.

The mechanism of how HCC (liver cancer) is formed is quite heterogeneous and complex, hepatitis B and hepatitis C play a big role, but they are not the sole perpetrators.  Alcohol is an important cofactor in patients with either hepatitis B or C infection with cirrhosis that leads to HCC (liver cancer), the mechanism of which is not clear, or at least unknown to me.  I read somewhere that telomerase is even involved.

Dr. Baruch Blumberg: A towering figure in medicine, a humble scientist and a great man           
It would be remiss of me not to mention Dr. Baruch Blumberg while talking about hepatitis B.  He discovered Australia antigen, later proved to be hepatitis B surface antigen (HBsAg), the origin of hepatitis B infection in mid-1960s, leading to the Nobel Prize in Medicine in 1976. His memoir is “The Hunt for a Killer virus: Hepatitis B”, a fascinating story.

He also made the first hepatitis B vaccine that was used in Taiwan.  His The Lancet article (Nov. 1, 1969) connected hepatitis B related cirrhosis to hepatocellular carcinoma (primary liver cancer).  Another related article was also published on July 5, 1975 Lancet



Medicine is complex                                                                                                                          Like Oppenheimer told his students at U.C. Berkeley, “I can make it clearer, but I cannot make it simpler.”  I am hoping you would paraphrase Enrico Fermi that before you read this article, you’re confused, and after reading this article, you’re still confused, but at a higher level.

Friday, February 3, 2017

Dr. Emil Frei III and Dr. Emil Freireich and the conquer of the childhood leukemia: The incomparable pair

Of the many books and ebook Christmas gifts I received this year, one is a Kindle ebook (The Undoing Project by Michael Lewis), which is a story of the friendship and collaboration between two Israel psychologists, about whom I knew nothing before receiving this gift.  I must have talked about the collaboration and the friendship between two scientists all the time, as my daughters told me that was the reason why the ebook was chosen.

I never tired of telling the stories of James Watson and Francis Crick, Michael Brown and Joseph Goldstein (LDL receptor), Lise Meitner and Otto Hahn (nuclear fission and the gender discrimination of Nobel Prize).

Fathers of combination chemotherapy and the conquer of childhood leukemia
The focus of this post is about the story of the fathers of combination cancer chemotherapy and the conquer of the childhood leukemia.  It is less well known to the general public, but no less important or impact to the clinical medicine.

It is a story of the two “near-namesakes” physicians.

Dr. Emil Frei III
Dr. Emil Freireich

‘Personal connection’ to a medical giant
I am writing this with reverence as well as “affection”, as we have a slight ‘personal’ connection to Dr. Emil Frei, who is the uncle of one of our best friends in Waynesburg.  We heard the first-hand stories about him from time to time until his passing in 2013.  Dr. Emil Freireich, ages 89, is still at MD Anderson Cancer Center in Houston.

Through our friend’s kind consideration and arrangement, Janice, during her freshman year in Boston, was fortunate to be invited to a party in Dr. and Mrs. Frei’s home, at which time Dr. Frei was the Director of the Dana Farber Cancer Institute. 

Janice was overwhelmed by the cordial, friendly and intellectual gathering.  She said, without knowing his profession, one would guess Dr. Frei is a musician.


The birth of combination chemotherapy
Up to early 1950s the childhood leukemia is always fatal.  Dr. Sidney Farber (the founder of Dana Farber Cancer Institute) was considered the father of modern chemotherapy.  His article, using amniopterin (an anti-folic acid agent) to treat leukemia, at NEJM in 1948, was made with ridicule.


The response to the single agent chemotherapy was very temporary and dismal.  The breakthrough came from the idea of combination chemotherapy that was pioneered by Dr. Frei and Dr. Freireich in mid-1950s.  By 1965, the invariably fatal childhood leukemia had achieved the long term survival of 40%.  It is now more than 80%.

Even Dr. William Dameshek, the opinionated Harvard-trained hematologist and one of the most prominent early opponents, was convinced and wrote, “The mood among pediatric oncologists changed virtually overnight from one of ‘compassionate fatalism’ to one of ‘aggressive optimism’.”

The “butcher shop” and the “meat market”
However the road was not easy and smooth; to administer multiple toxic drugs to a very fragile and sick child was considered insane and cruel by many.  For a while the leukemia ward at the National Cancer Institute (NCI) was dubbed as “butcher shop”. 

In his “The Death of Cancer”, Dr. Vincent DeVita had a candid and vivid description of what Dr. Frie and Freireich had to endure.  The medical community was scandalized.  When the two doctors talked in the Grand Round at the National Cancer Institute, it was a verbal bloodbath.  Some of the doctors in the audience would scream out loud, “This is meat market!  What a butcher shop!”

Without the resilience and perseverance of Dr. Frei and Freireich, the fruit of the sweet success cannot be born.

The complementary and synergistic relationship
The two doctors arrived at NCI almost the same time; Dr. Frei a few months earlier. In an interview Dr. Freireich recalled how they first met at NCI.  It was Dr. Freireich reporting to NCI.

I looked up; I was looking at the name of the doors. It was rows of rooms. Twelve---said, Emil Frei III. Damn! It's government typical government stuff--cannot even spell my name! So I walked into this room. And here is this tall, skinny guy with no hair.  So I said Sir! Dr. Zubrod told me this was my office.  You're in my office. He said, Are you kidding? This is my office! What's your name? So that's how Frei and Freireich met the first time.  He said You got the wrong number: You're next door.It actually was next door. . .. so we've been friends from April 10, 1955 to this day--friends and intellectual collaborators.  I have very high regard for Emil Frei III, and we really fought the war there in the clinical center.”

These two intellectuals didn’t share the same personality.  Dr. Freireich was as aggressive and impulsive as Dr. Frei was calm and serene.  Their personal and professional relationship was complementary and synergistic.  Many doctors at NCI wondered they both were maniacs or geniuses in those days of trial and tribulation, though.

In his “The Emperor of All Maladies: A Biography of Cancer,” Dr. Siddhartha Mukherjee said of Dr. Frei, “He was charming, soft-spoken and careful. To watch him manage critically ill children and their testy, nervous parents was to watch a champion swimmer glide through water—so adept in the art that he made artistry vanish.

After the passing of Dr. Frei in 2013, Dr. Freireich reminisced, “It turned out my office was next door, and Tom and I became friends and colleagues then and for the rest of our lives.  He provided administrative and psychological leadership and served as a buffer for me at NCI. He was the perfect person to lead programs that innovate.”  Dr. Freireich also pointed out that Dr. Frei had saved him from being fired three times. It has been known within NCI that Frei’s job was to keep Freireich from getting in trouble.

Dr. Emil Freireich
I have never seen Francis Crick in a modest mood.” is how James Watson began his Double Helix.  Dr. Frei once quipped, “I have never seen Freireich in a moderate mood” along the same line.

Dr. Frei left NCI for MD Anderson Cancer Center in 1965; Dr. Freireich followed him there shortly thereafter and never left.  Dr. Frei then moved to Dana-Farber Cancer Institute in 1972 and took over as the director when Dr. Farber died in 1973.  No one would argue that Dr. Frei was the one who made NCI, MD Anderson Cancer Center and Dana-Farber Cancer Institute of what they are today.  His administrative skill and leadership matches his medical prowess and innovation.

A friend recalled Dr. Frei used to say, “We’re here to move the field.”  That was his mantra.

A great doctor and a great man
Dr. Frei, known to his colleagues, family, and friends as Tom, was optimistic, kind, generous and supportive, a great educator, training generation of first-rate oncologists.  One of them is Dr. Vincent DeVita, who also shared the 1972 Lasker Award with Dr. Frei and Dr. Freireich.  He was a favorite of young cancer patients in Dana-Farber's Jimmy Fund Clinic when he dressed up as Big Bird or Darth Vader for parties. “His sense of humor is legendary at Dana-Farber.

In Dr. Frei’s obituary of Oncology Times, I read,

Frei and Freireich used the same approach for Hodgkin lymphoma, also making it curable in many instances,. . .”

This is not quite correct; it was Dr. Vincent DeVita who used combination chemotherapy for Hodgkin lymphoma (for which he had the honor to share Lasker Award), not Dr. Frei or Dr. Freieich.

Dr. Emil Frei and Edward Kennedy Jr.
Dr. Frei’s most famous patient, Edward Kennedy, Jr.
While at Dana-Farber he turned his research to osteogenic sarcoma and non-Hodgkin lymphoma.  Famous physician tends to have famous patient, no exception for Dr. Frei.  In 1973 Edward Kennedy Jr., then aged 12 lost a leg to osteosarcoma.  He underwent intensive chemotherapy for two years.  In NY Times obituary of Dr. Frei, we read of what Edward Kennedy Jr. said, “I honestly believe that Dr. Frei saved my life. My father obviously had incredible resources in terms of being able to identify the most capable people. And of all the people in the world, he asked Dr. Frei to take care of me.”

Dr. David Ho: 1996 Man of the Year
Combination chemotherapy is a revolutionary concept
Recall 1996 Time’s Man of the Year, Dr. David Ho (who was born in Taiwan) who pioneers combination anti-retroviral therapy that helped lifting a death sentence for HIV patients.

The concept of combination chemotherapy that Dr. Frei and Dr. Freireich pioneered not only benefited leukemia patients, it also opened the paths to much more successful combination chemotherapies for other type of cancers.  The field was moved, indeed.

Wednesday, February 22, 2012

Remembrance: Renato Dulbecco 1914-2012

Renato Dulbecco died three days ago (Feb. 19) at age of 97, he would have been 98 today as he was born 2/22/1914NY Times had an obituary on him yesterday.  As yet I haven't read his “Remembrance” (WSJ obituary).  It would be an inexcusable oversight for not reporting the death of such a giant in medicine.  I am disappointed; here is my version of Remembrance of Renato Dulbecco.

He was the one demonstrated that DNA of a virus can integrate into the chromosomal DNA of the host cell, causing the uncontrolled cell growth, which is the genetic basis of cancer, and for which he was awarded a Nobel Prize in 1975.  His article in Science in 1986 helped starting the Human Genome Project.
photo credit: N.Y. Times
He was in the same class with Salvador Luria in a medical school in Italy.  As we know Luria and Max Delbrück spent the war (WWII) years as the “enemy scientists” in the States (Luria from Italy and Delbrück from Germany); they shared the Nobel Prizes in 1969.  After the war in 1947 Luria went back to Italy to bring Dulbecco to his Lab at Indiana University in Bloomington, Indiana.  Dulbecco and James Watson (Dulbecco was 14 years Watson’s senior) were with Luria in the same time.

Dulbecco wrote an article reminiscing their “Phages Days in Indiana” in “Inspiring Science: Jim Watson and the Age of DNA” (a 'must have' book for those who are interested in medicine and history).  Dulbecco wrote on the day Luria announced a “Whiz Kid” coming from University of Chicago, at which time he himself just arrived from Italy and didn’t know what “Whiz Kid” means.

Watson entered University of Chicago at age of 15, but Dulbecco was also a “Whiz Kid” himself entering the university at age of 16.  His initial interest was math and physics before entering medical school.  Dulbecco wrote “The plaque technique and the development of quantitative animal virology” in “Phage and the origins of molecular biology” (again a 'must have' book) which was a break through technique in the frontier field when molecular biology was being born.  He couldn’t have done it without his savvy and strength in math.

When Luria sent Watson to Cambridge University to eventually meet up with Francis Crick, Dulbecco was recruited to Caltech by Delbrück.  He later went to Salk Institute, of which he was one of the founding fellows and eventually became the president of the Institute.  Paul Berg worked with Dulbecco at Salk Institute and thus born the recombinant DNA technique, for which Berg was awarded the Nobel Chemistry Prize in 1980.  This is Chapter 22 “The creation of altered forms of life” in Alan Lightman’s The Discoveries.

Before coming to the States in 1947, Dulbecco also worked at Rita Levi-Montalcini’s Lab in Italy.  She was awarded the Nobel Prize for discovering the growth factor, the study she did in the Washington University at St. Louis (founded by T.S. Eliot's grandfather), where Paul Berg began to follow Arthur Kornberg before they moved to Stanford.  Rita Levi-Montalcini will be 103 years old next month.

Dulbecco wrote an addendum to his autobiography in the nobel.com site in 2005, “At the beginning of 2006, when I will reach 92 years of age, I will give up the Italian connections, and will retire at La Jolla, to follow the work going on at the Salk Institute, and to play the piano.”      

I recently read Malcolm Gladwell’s “Outliers: the Story of Success”; I was going to write a book report (a critique), but never got time to do it.  If you read the above story carefully, you’ll notice the secret (or not-so-secret) of getting a Nobel Prize is to go to work with a Nobel laureate or a future/potential one.