|
|
Cancer knows no boundaries and as
such affects children throughout the world. It is estimated that about 160,000 children
world-wide are diagnosed with cancer each year, and approximately 90,000 will eventually
die from their illness.1 The exact number
of new cases is not known because the number of children with cancer is not registered
in many countries.
In developed countries like the
United States
,
Canada
, Western European countries,
Japan
and
Australia
, cancer remains the most common disease killer of children. In developing countries,
more than one in two children diagnosed with cancer are likely to die.2
This is because cancer is detected late and only a small proportion of children
have access to the comprehensive cancer treatments currently available in the developed
world. Childhood cancer is becoming a more important health issue for these countries
and the world community as infectious diseases and diarrhea become increasingly
eliminated.
In the U.S. and other developed countries,
the 1970s-80s brought the advent of chemotherapy ‘cocktails’ applied to childhood
cancer, where toxic compounds that preferentially killed the tumor cells kept many
children from death. In spite of tens of millions of public dollars being allocated
towards clinical trial research in the
U.S. in the past decade, there has been no change in survivorship of childhood cancer in the past 10 years.2 From 1975 to 1998 the annual death rate from childhood cancer in the U.S. declined at a rate of 2.7% per year. Despite very aggressive therapies that approach the limits of tolerability for the child, the overall survival rate for
|
|
|
childhood cancer has remained unchanged since 1998. One in four children who are
diagnosed with cancer in the U.S. will die within five years of their diagnosis,
and 30% of those that do survive have severe side effects, including cognitive deficits,
kidney failure, heart failure, and secondary cancers caused from the traditional
toxic treatments. Because of the high level of toxicity
associated with many current treatments and the plateau in survivorship rates, future
success is dependent upon the development of new therapeutic approaches.
Newly emerging adult cancer therapy
is focused on drugs that kill only the cancer, and are not toxic to the normal cells
of the patient. They accomplish this by using molecular genetic approaches to identify
the ‘Achilles heel’ of each specific tumor type, then attacking this weak spot in
a highly specific manner. This “targeted therapeutics” has had great success in
a number of adult cancers. Unfortunately, pediatric cancers are so different from
adult cancers that targeted therapeutics must be developed specifically for pediatric
cancer. It is imperative that research initiatives take place for childhood cancer
that utilizes and integrates the latest molecular techniques for pediatric cancers,
including: comparative genomic hybridization, large-scale re-sequencing of key oncogenes,
proteomic profiling (particularly signaling pathways; phosphoproteomic profiling),
and mRNA profiling.
The identification of such therapeutic
targets is essential to the future progress in identifying more effective therapies
for children with cancer. Specifically, “target identification” is the first step
in the high throughput drug screening pipeline (HTS), enabling subsequent assay
development, high throughput screening, drug development, and pre-clinical and clinical
studies. Through the development of molecularly targeted drugs for children with
cancer, children world-wide could benefit from cancer therapies that would require
minimal supportive care in contrast to today’s toxic therapy. Children would benefit
from additional drugs leading to a greater number of cures, and cures that would
not be associated with life-long severe medical late-effects currently caused by
standard cancer treatments.
|
|
|
|
|
|
|
|
|
|