Vol. 305. No.4. October 2011
A New Ally Against Cancer
Author: Eric von Hofe
Cancer was used to be thought as a death sentence just a few decades ago. However, increasing technology and advanced researches have been making it possible for patients to live longer and even completely cure cancer. Von Hofe, a president of Antigen Express (a company that is developing a vaccine for active immunotherapy) in Worcester, Massachusetts, introduced a brief history of cancer treatments including a development of cancer vaccination, its failure, and its recent resurgence.
Before a recent introduction of a new cancer treatment, immunotherapy, we knew only three therapies: surgery, chemotherapy, and radiation. However, the concept of immunotherapy, which treats cancer by inducing, enhancing and/or suppressing its own immune system, was already developed in 1890s by William B. Coley. In those days, no one knew anything about immune cells such as CD4 and CD8 T cells that take a role in killing foreign matters and cancer cells in the body. However, Coley hypothesized that a high fever (one of the immune responses) would kill malignant cells in the body. By using a treated, harmless bacteria solution that he created, he discovered that patients who received this solution developed a fever and lived longer than those who did not receive it.
Even though this was a remarkable findings that will eventually lead to the present cancer vaccination, chemotherapy appeared in 1950s has been taking over the throne of the cancer treatment for a long time until today. This was due to a fact that chemotherapy, even its high toxicity, showed its results much quicker than the immunotherapy.
Even under such an out-of-spotlight, some scientist have been researching and attempting the development of cancer vaccine that triggers only as much side effects as a flu. In 2002, researchers at the National Cancer Institute (NCI) revealed more detailed immune system and proved that a cancer treatment by boosting T-cells (immune cells that kill foreign invaders and tumors) is possible and requires the presence of two types of T-cells: CD8+ T-cells and CD4+ T-cells. However, the method they used in their experiment with melanoma patients was not called as a cancer vaccination, because they took out CD8+ and CD4+ T-cells from the patients, proliferated them in a test tube, and put them back into the patients' bodies. In order to apply this method to a cancer vaccine, the proliferation process must be done inside the body.
The key is to make both T-cells proliferate in a large number in a relatively short period of time in order to overstep the growth of cancer. The number of cloned immune cells used by NCI's experiment was more than 70 billion for each patient! In general, cancer cells divide at a much faster rate than normal cells do, so a great number of T-cells are required to catch up with the cancer cells's pace. Furthermore, as cancer cells grow, they secret chemicals that diminish activities of T-cells, preventing them from being killed by the immune cells. Thus, to compensate these two factors, cancer vaccine must trigger effectively both T-cells to proliferate in a very large number.
In 2010, the first cancer vaccine was approved by FDA for advanced prostate cancer. It is called Provenge, manufactured by Dendreon and some other companies. Provenge provides a dendritic cell (another immune cell) targeted to a specific type of cancer cells. A role of the dendritic cells is to patrol an entire body and to report the existence of cancer cells to T-cells, sitting in lymph nodes, so that T-cells start cloning specific for the cancer. Even though this vaccine causes only mild side effects and proved an effectiveness in prostate cancer patients, one big problem is that this vaccine is a custom-made for each patient. In other words, this vaccine must be made from individual patient by taking out dendritic cells from him/her, loading the cells with the cancer-specific protein, and then putting them back to the patient. Since this vaccine is not universal for everyone and must be developed from each patient one at a time, it costs about $93,000 for a full course of treatment.
In order to reduce the cost and to develop a vaccine that one type of vaccine can be used for all people in any kind of cancer, von Hof's company, Antigen Express, is researching a new approach. They found so far that a few modification of a peptide (a piece of protein), found on the surface of breast cancer cells, drastically increased its ability to stimulate both CD8+ and CD4+ T-cells. This means that providing this modified peptide as a vaccine to breast cancer patients would trigger a production of both T-cells in large number and kill the breast cancer cells. Von Hof believes that using a peptide instead of a dendritic cell is more cost effective because peptides are small in size, easily synthesized, and readily manipulated. Also, the peptides, which they identified, are shown in many people with various cancer types, so it would be possible that one kind of peptide can be used to cure many different cancers. In the end, von Hof concluded that cancer vaccinations are still under clinical trials, but they will be a crucial role in cancer treatments in the future.
This article greatly appeals to my curiosity in cancer. When I saw "cancer vaccination" in the beginning of this article, my heart leaped up, and I was excited that finally a cancer-free era came! As I continued reading it, however, I realized that this vaccination is not the one I imagined. The cancer vaccine here is not a regular vaccine that we are familiar with. Regular vaccines trigger our body to make antibodies for specific pathogens such as flu virus so that our immune system can quickly make more antibodies to fight against the pathogens once we encounter them in the future. Therefore, our immune system kills them before we have a symptom. On the other hand, the cancer vaccine is not given in prior to a cancer development but given AFTER that along with other treatments such as chemotherapy. Thus, the cancer vaccination does not prevent having cancer but does potentially prevent recurrence of the disease for cancer survivors. Even so, this scientific improvement is remarkable, because one of the scary aspects of cancer is a recurrence. If this vaccine became readily available to many patients with various cancer types in the near future, this would give them and their family a hope that they can live much longer life.
The following has been edited;
Scientific American
Cancer was used to be thought as a death sentence just a few decades ago. However, increasing technology and advanced researches have been making it possible for patients to live longer and even completely cure cancer. Von Hofe, a president of Antigen Express (a company that is developing a vaccine for active immunotherapy) in Worcester, Massachusetts, introduced a brief history of cancer treatments including a development of cancer vaccination, its failure, and its recent resurgence.
Before a recent introduction of a new cancer treatment, immunotherapy, we knew only three therapies: surgery, chemotherapy, and radiation. However, the concept of immunotherapy, which treats cancer by inducing, enhancing and/or suppressing its own immune system, was already developed in 1890s by William B. Coley. In those days, no one knew anything about immune cells such as CD4 and CD8 T cells that take a role in killing foreign matters and cancer cells in the body. However, Coley hypothesized that a high fever (one of the immune responses) would kill malignant cells in the body. By using a treated, harmless bacteria solution that he created, he discovered that patients who received this solution developed a fever and lived longer than those who did not receive it.
Even though this was a remarkable findings that will eventually lead to the present cancer vaccination, chemotherapy appeared in 1950s has been taking over the throne of the cancer treatment for a long time until today. This was due to a fact that chemotherapy, even its high toxicity, showed its results much quicker than the immunotherapy.
Even under such an out-of-spotlight, some scientist have been researching and attempting the development of cancer vaccine that triggers only as much side effects as a flu. In 2002, researchers at the National Cancer Institute (NCI) revealed more detailed immune system and proved that a cancer treatment by boosting T-cells (immune cells that kill foreign invaders and tumors) is possible and requires the presence of two types of T-cells: CD8+ T-cells and CD4+ T-cells. However, the method they used in their experiment with melanoma patients was not called as a cancer vaccination, because they took out CD8+ and CD4+ T-cells from the patients, proliferated them in a test tube, and put them back into the patients' bodies. In order to apply this method to a cancer vaccine, the proliferation process must be done inside the body.
The key is to make both T-cells proliferate in a large number in a relatively short period of time in order to overstep the growth of cancer. The number of cloned immune cells used by NCI's experiment was more than 70 billion for each patient! In general, cancer cells divide at a much faster rate than normal cells do, so a great number of T-cells are required to catch up with the cancer cells's pace. Furthermore, as cancer cells grow, they secret chemicals that diminish activities of T-cells, preventing them from being killed by the immune cells. Thus, to compensate these two factors, cancer vaccine must trigger effectively both T-cells to proliferate in a very large number.
In 2010, the first cancer vaccine was approved by FDA for advanced prostate cancer. It is called Provenge, manufactured by Dendreon and some other companies. Provenge provides a dendritic cell (another immune cell) targeted to a specific type of cancer cells. A role of the dendritic cells is to patrol an entire body and to report the existence of cancer cells to T-cells, sitting in lymph nodes, so that T-cells start cloning specific for the cancer. Even though this vaccine causes only mild side effects and proved an effectiveness in prostate cancer patients, one big problem is that this vaccine is a custom-made for each patient. In other words, this vaccine must be made from individual patient by taking out dendritic cells from him/her, loading the cells with the cancer-specific protein, and then putting them back to the patient. Since this vaccine is not universal for everyone and must be developed from each patient one at a time, it costs about $93,000 for a full course of treatment.
In order to reduce the cost and to develop a vaccine that one type of vaccine can be used for all people in any kind of cancer, von Hof's company, Antigen Express, is researching a new approach. They found so far that a few modification of a peptide (a piece of protein), found on the surface of breast cancer cells, drastically increased its ability to stimulate both CD8+ and CD4+ T-cells. This means that providing this modified peptide as a vaccine to breast cancer patients would trigger a production of both T-cells in large number and kill the breast cancer cells. Von Hof believes that using a peptide instead of a dendritic cell is more cost effective because peptides are small in size, easily synthesized, and readily manipulated. Also, the peptides, which they identified, are shown in many people with various cancer types, so it would be possible that one kind of peptide can be used to cure many different cancers. In the end, von Hof concluded that cancer vaccinations are still under clinical trials, but they will be a crucial role in cancer treatments in the future.
This article greatly appeals to my curiosity in cancer. When I saw "cancer vaccination" in the beginning of this article, my heart leaped up, and I was excited that finally a cancer-free era came! As I continued reading it, however, I realized that this vaccination is not the one I imagined. The cancer vaccine here is not a regular vaccine that we are familiar with. Regular vaccines trigger our body to make antibodies for specific pathogens such as flu virus so that our immune system can quickly make more antibodies to fight against the pathogens once we encounter them in the future. Therefore, our immune system kills them before we have a symptom. On the other hand, the cancer vaccine is not given in prior to a cancer development but given AFTER that along with other treatments such as chemotherapy. Thus, the cancer vaccination does not prevent having cancer but does potentially prevent recurrence of the disease for cancer survivors. Even so, this scientific improvement is remarkable, because one of the scary aspects of cancer is a recurrence. If this vaccine became readily available to many patients with various cancer types in the near future, this would give them and their family a hope that they can live much longer life.
The following has been edited;
Vol. 305. No.4. October 2011
A New Ally Against Cancer
Author: Eric von Hofe
Cancer used to be thought of as a death sentence just a few decades ago. However, increasing technology and advanced research has been making it possible for patients to live longer and even completely be cured of cancer. Von Hofe, a president of Antigen Express (a company that is developing a vaccine for active immunotherapy) in Worcester, Massachusetts, introduced a brief history of cancer treatments including a development of cancer vaccination, its failure, and its recent resurgence.
Before a recent introduction of a new cancer treatment, immunotherapy, we knew only three therapies: surgery, chemotherapy, and radiation. However, the concept of immunotherapy, which treats cancer by inducing, enhancing and/or suppressing its own immune system, was already developed in 1890s by William B. Coley. In those days, no one knew anything about immune cells such as CD4 and CD8 T cells that take a role in killing foreign matters and cancer cells in the body. However, Coley hypothesized that a high fever (one of the immune responses) would kill malignant cells in the body. By using a treated, harmless bacteria solution that he created, he discovered that patients who received this solution developed a fever and lived longer than those who did not receive it.
Even though this was a remarkable finding that would eventually lead to the present cancer vaccination, chemotherapy which appeared in the 1950s still remains at the throne of cancer treatment even today. This is due to the fact that chemotherapy, even its high toxicity, shows its results much quicker than the immunotherapy.
Outside of the spotlight, some scientists have been researching and attempting the development of cancer vaccines that trigger only as much side effects as a flu. In 2002, researchers at the National Cancer Institute (NCI) revealed a more detailed immune system and proved that boosting T-cells (immune cells that kill foreign invaders and tumors) is an effective cancer treatment that requires the presence of two types of T-cells: CD8+ T-cells and CD4+ T-cells. However, the method they used in their experiment with melanoma patients was not called a cancer vaccination, because they took out CD8+ and CD4+ T-cells from the patients, proliferated them in a test tube, and put them back into the patients' bodies. In order to apply this method to a cancer vaccine, the proliferation process must be done inside the body.
The key is to make both T-cells proliferate in a large number in a relatively short period of time in order to overstep the growth of cancer. The number of cloned immune cells used by NCI's experiment was more than 70 billion for each patient! In general, cancer cells divide at a much faster rate than normal cells do, so a great number of T-cells are required to catch up with the cancer cells's pace. Furthermore, as cancer cells grow, they secrete chemicals that diminish the activities of T-cells, preventing them from being killed by the immune cells. Thus, to compensate for these two factors, cancer vaccine must effectively trigger both T-cells to proliferate in very large numbers.
In 2010, the first cancer vaccine was approved by the FDA for advanced prostate cancer. It is called Provenge, manufactured by Dendreon and some other companies. Provenge provides a dendritic cell (another immune cell) targeted to specific types of cancer cells. A role of the dendritic cells is to patrol an entire body and to report the existence of cancer cells to T-cells, sitting in lymph nodes, so that T-cells start cloning specific for the cancer. Even though this vaccine causes only mild side effects and has proven to be effective in prostate cancer patients, one big problem is that this vaccine is a custom-made for each patient. In other words, this vaccine must be made from each individual patient by taking out their dendritic cells, loading the cells with the cancer-specific protein, and then putting them back into the patient. Since this vaccine is not universal for everyone and must be developed from each patient one at a time, it costs about $93,000 for a full course of treatment.
In order to reduce the cost and to develop a vaccine that can be used for all people with any kind of cancer, von Hof's company, Antigen Express, is researching a new approach. They found so far that a few modifications of a peptide (a piece of protein), found on the surface of breast cancer cells, drastically increased the ability to stimulate both CD8+ and CD4+ T-cells. This means that providing this modified peptide as a vaccine to breast cancer patients would trigger a production of both T-cells in large number and kill the breast cancer cells. Von Hof believes that using a peptide instead of a dendritic cell is more cost effective because peptides are small in size, easily synthesized, and readily manipulated. Also, the peptides, which they identified, are shown in many people with various cancer types, so it would be possible that one kind of peptide could be used to cure many different cancers. In the end, von Hof concluded that cancer vaccinations are still under clinical trials, but they will be a crucial role in cancer treatments in the future.
This article greatly appeals to my curiosity in cancer. When I saw "cancer vaccination" in the beginning of this article, my heart leaped up, and I was excited that finally a cancer-free era had arrived! As I continued reading it, however, I realized that this vaccination is not the one I imagined. The cancer vaccine here is not a regular vaccine that we are familiar with. Regular vaccines trigger our body to make antibodies for specific pathogens such as the flu virus so that our immune system can quickly make more antibodies to fight against the pathogens once we encounter them in the future. Therefore, our immune system kills them before we have a symptom. On the other hand, the cancer vaccine is not given prior to a cancer development but given AFTERWARDS along with other treatments such as chemotherapy. Thus, the cancer vaccination does not prevent having cancer but does potentially prevent the recurrence of the disease for cancer survivors. Even so, this scientific improvement is remarkable, because one of the scary aspects of cancer is a recurrence. If this vaccine became readily available to many patients with various cancer types in the near future, this would give them and their family a hope that they can live a much longer life.
Cancer used to be thought of as a death sentence just a few decades ago. However, increasing technology and advanced research has been making it possible for patients to live longer and even completely be cured of cancer. Von Hofe, a president of Antigen Express (a company that is developing a vaccine for active immunotherapy) in Worcester, Massachusetts, introduced a brief history of cancer treatments including a development of cancer vaccination, its failure, and its recent resurgence.
Before a recent introduction of a new cancer treatment, immunotherapy, we knew only three therapies: surgery, chemotherapy, and radiation. However, the concept of immunotherapy, which treats cancer by inducing, enhancing and/or suppressing its own immune system, was already developed in 1890s by William B. Coley. In those days, no one knew anything about immune cells such as CD4 and CD8 T cells that take a role in killing foreign matters and cancer cells in the body. However, Coley hypothesized that a high fever (one of the immune responses) would kill malignant cells in the body. By using a treated, harmless bacteria solution that he created, he discovered that patients who received this solution developed a fever and lived longer than those who did not receive it.
Even though this was a remarkable finding that would eventually lead to the present cancer vaccination, chemotherapy which appeared in the 1950s still remains at the throne of cancer treatment even today. This is due to the fact that chemotherapy, even its high toxicity, shows its results much quicker than the immunotherapy.
Outside of the spotlight, some scientists have been researching and attempting the development of cancer vaccines that trigger only as much side effects as a flu. In 2002, researchers at the National Cancer Institute (NCI) revealed a more detailed immune system and proved that boosting T-cells (immune cells that kill foreign invaders and tumors) is an effective cancer treatment that requires the presence of two types of T-cells: CD8+ T-cells and CD4+ T-cells. However, the method they used in their experiment with melanoma patients was not called a cancer vaccination, because they took out CD8+ and CD4+ T-cells from the patients, proliferated them in a test tube, and put them back into the patients' bodies. In order to apply this method to a cancer vaccine, the proliferation process must be done inside the body.
The key is to make both T-cells proliferate in a large number in a relatively short period of time in order to overstep the growth of cancer. The number of cloned immune cells used by NCI's experiment was more than 70 billion for each patient! In general, cancer cells divide at a much faster rate than normal cells do, so a great number of T-cells are required to catch up with the cancer cells's pace. Furthermore, as cancer cells grow, they secrete chemicals that diminish the activities of T-cells, preventing them from being killed by the immune cells. Thus, to compensate for these two factors, cancer vaccine must effectively trigger both T-cells to proliferate in very large numbers.
In 2010, the first cancer vaccine was approved by the FDA for advanced prostate cancer. It is called Provenge, manufactured by Dendreon and some other companies. Provenge provides a dendritic cell (another immune cell) targeted to specific types of cancer cells. A role of the dendritic cells is to patrol an entire body and to report the existence of cancer cells to T-cells, sitting in lymph nodes, so that T-cells start cloning specific for the cancer. Even though this vaccine causes only mild side effects and has proven to be effective in prostate cancer patients, one big problem is that this vaccine is a custom-made for each patient. In other words, this vaccine must be made from each individual patient by taking out their dendritic cells, loading the cells with the cancer-specific protein, and then putting them back into the patient. Since this vaccine is not universal for everyone and must be developed from each patient one at a time, it costs about $93,000 for a full course of treatment.
In order to reduce the cost and to develop a vaccine that can be used for all people with any kind of cancer, von Hof's company, Antigen Express, is researching a new approach. They found so far that a few modifications of a peptide (a piece of protein), found on the surface of breast cancer cells, drastically increased the ability to stimulate both CD8+ and CD4+ T-cells. This means that providing this modified peptide as a vaccine to breast cancer patients would trigger a production of both T-cells in large number and kill the breast cancer cells. Von Hof believes that using a peptide instead of a dendritic cell is more cost effective because peptides are small in size, easily synthesized, and readily manipulated. Also, the peptides, which they identified, are shown in many people with various cancer types, so it would be possible that one kind of peptide could be used to cure many different cancers. In the end, von Hof concluded that cancer vaccinations are still under clinical trials, but they will be a crucial role in cancer treatments in the future.
This article greatly appeals to my curiosity in cancer. When I saw "cancer vaccination" in the beginning of this article, my heart leaped up, and I was excited that finally a cancer-free era had arrived! As I continued reading it, however, I realized that this vaccination is not the one I imagined. The cancer vaccine here is not a regular vaccine that we are familiar with. Regular vaccines trigger our body to make antibodies for specific pathogens such as the flu virus so that our immune system can quickly make more antibodies to fight against the pathogens once we encounter them in the future. Therefore, our immune system kills them before we have a symptom. On the other hand, the cancer vaccine is not given prior to a cancer development but given AFTERWARDS along with other treatments such as chemotherapy. Thus, the cancer vaccination does not prevent having cancer but does potentially prevent the recurrence of the disease for cancer survivors. Even so, this scientific improvement is remarkable, because one of the scary aspects of cancer is a recurrence. If this vaccine became readily available to many patients with various cancer types in the near future, this would give them and their family a hope that they can live a much longer life.
