A New Use for One of the Oldest “New” Drugs

With the profusion of new targeted agents entering the clinical arena, a report from the American Society of Hematology bears consideration.

The trial known as the SORAML trial enrolled 276 patients with newly diagnosed acute myelogenous leukemia. The patients were between the ages of 18 and 60. All patients received a standard chemotherapy regimen. The patients were then randomized to receive Sorafenib or placebo. Patients on the Sorafenib arm then remained on a maintenance therapy for twelve months.

While the achievement of complete remission was almost identical between the two arms at 59% and 60%, the event free survival demonstrably favored the Sorafenib group at 20.5 months versus 9.2 months. At three years of follow-up 40% of the Sorafenib group were well with only 22% of the placebo group still in remission. This corresponds to a three-year relapse free survival of 38% for placebo and 56% for Sorafenib (P=0.017).

The results are of interest on several levels.
1.    Sorafenib a multitargeted tyrosine kinase inhibitor was approved in December 2005 for the treatment of renal cell carcinoma. This makes Sorafenib one of the first targeted agents to achieve FDA approval.

2.     Sorafenib has many modes of action and it is not entirely clear which of its functions were responsible for the superior survival in this AML study.

3.    Sorafenib’s approval reflects a rather convoluted and interesting history. When first developed the drug was designed to target the oncogene B-Raf. As a result the drug was introduced into early clinical trials for the treatment of advanced melanoma, a disease known to be associated with B-Raf mutation. As the drug proved ineffective, it appeared unlikely to gain FDA approval. That is, until it showed cross reactivity with VEGF pathway associated with tumor cell vascularity. A successful trial published in the New England Journal of Medicine then led to the approval.

Now, nine years later this old new drug has gained new life. This time in acute myelogenous leukemia.

The term “dirty drug” refers to agents that target many kinases at the same time. Sorafenib is an example of a “dirty drug.” However it is Sorafenib’s “dirty drug” quality that led first to its approval and most likely now leads to its application in AML. This reflects the fact that Sorafenib may be inhibiting B-Raf signaling associated with the common mutation in Ras upstream of B-Raf or it may reflect Flt3 a secondary activity associated with Sorafenib.

Indeed B-Raf and Flt3 may not be upregulated in every patient, but could serve a function of permissive activity granting an additional survival signal to the AML cells as they go through induction therapy. These subtleties of drug effect may escape genomic analysis as the true “target” may not be mutated, upregulated or amplified. No doubt the investigators in this study will conduct gene sequencing to determine whether there is a driver mutation associated with the advantage reported in this clinical study. What will be intriguing is to determine whether that advantage is an abnormal gene functioning within these cancerous cells or possibly a normal gene functioning abnormally in these cancer cells. More to come.

The Case for the Metabolic Basis of Cancer Gains Traction

Researchers from the Huntsman Cancer Institute at the University of Utah reported an interesting finding with far-reaching implications.

In their study of the rare tumor known as alveolar soft part sarcoma (ASPS), they examined the well-established chromosomal translocation that occurs between chromosomes 17 and X. This results in the 250px-Protein_ASPSCR1_PDB_2al3production of a fusion protein dubbed ASPSCR1-TFE3. Like other fusion proteins described in malignancies such as lymphoma, acute pro-myelocytic leukemia and chronic myelogenous leukemia, a novel function occurs when two disparate genomic elements are spliced together.

In this instance, the ASPSCR1-TFE3 gene product functions as a lactate transporter. Strikingly, every mouse in which the gene was up regulated developed a tumor. The locations of tumor, in the skull and near the eye, both represented areas of high lactate concentration. In humans, this tumor occurs in skeletal muscle, also associated with high lactate production.

Since 1930, when Otto Warburg first described increased glycolysis (preferential use of sugars) in tumor cells, investigators have pondered the implication of inefficient glucose metabolism in the face of adequate oxygenation.

Human metabolism relies upon mitochondrial function to efficiently liberate the maximum amount of energy in the form of ATP from each glucose molecule. Glycolysis occurring in the cell cytoplasm is highly inefficient and produces only 1/18 of the amount of ATP that a full molecule of glucose can produce through mitochondrial oxidative phosphorylation. Recent molecular biological studies have established that the preferential use of glycolysis may represent the cells need to direct glucose away from energy production and toward the creation of essential structures like amino acids, lipids, and nucleic acids. With the rapid turnover of glucose, cells produce an overwhelming amount of lactate, which is then transported out of the cell. At least this has been the working hypothesis over many years.

More recently, investigators have begun to examine how lactate metabolism may represent the interplay between stromal fibroblast cells and tumor cells. Indeed, many tumor cells are now known to increase lactate uptake reflecting increased lactate production by fibroblasts that have been commandeered in the tumor microenvironment.

Lactate uptake is under the control of a family of transporters known as monocarboxylate transporters, of which nine have been described. These are expressed differently in various tissues, have different affinities for lactate and transport in one direction or another. These processes appear to be under the control of the major regulator of oxygen metabolism known as HIF-1 alpha. As cancer cells adapt to a high lactate environment, they can survive in low oxygen tension.

The preferential use of lactate as a source of energy is contrary to many dictates of current metabolic research that suggest that tumor cells preferentially use glucose and have limited capacity to utilize non-glucose energy sources like the ketone bodies acetoacetate and beta-hydroxybutyrate. Substantial literature on ketogenic diets suggests that these ketone bodies deprive cancer cells of needed nutrition and energy. The current discovery by the Utah investigators, as well as interesting work conducted by researchers in Italy on the prostate cancer, provide a new angle on some of these principles of cancer metabolism.

As the investigators from Utah note, the alveolar soft part sarcoma is a rare tumor, but the implications of these findings could be profound, as they force us to re-think tumorigenesis and the metabolic basis of cancer.

Genomic Profiling for Lung Cancer: the Good, the Bad and the Ugly

Genomic profiling has gained popularity in medical oncology. Using NextGen platforms, protein coding regions of human tumors known as exomes can be examined for mutations, amplifications, deletions, splice variants and SNPs. In select tumors the results can be extremely helpful. Among the best examples are adenocarcinomas of the lung where EGFr, ALK and ROS-1 mutations, deletions and/or re-arrangements identified by DNA analysis can guide the selection of “targeted agents” like Erlotinib and Crizotinib.

An article published in May 2014 issue of JAMA reported results using probes for 10 “oncogenic driver” mutations in lung cancer patients. They screened for at least one gene in 1,007 patients and all 10 genes in 733. The most common was k-ras at 25%, followed by EGFR in 17% and ALK in 8%. The incidence then fell off with other EGFr mutations in 4%, B-raf mutations in 2%, with the remaining mutations each found in less than 1%.

Median survival at 3.5 vs 2.4 years was improved for patients who received treatments guided by the findings (Kris MG et al, Using multiplex assays of oncogenic drivers in lung cancers to select targeted drugs. JAMA, May 2014). Do these results indicate that genomic analyses should be used for treatment selection in all patients? Yes and no.

Noteworthy is the fact that 28% of the patients had driver mutations in one of three genes, EGFr, HER2 or ALK. All three of these mutations have commercially available chemotherapeutic agents in the form of Erlotinib, Afatinib and Crizotinib. Response rates of 50% or higher, with many patients enjoying durable benefits have been observed. Furthermore, patients with EGFr mutations are often younger, female and non-smokers whose tumors often respond better to both targeted and non-targeted therapies. These factors would explain in part the good survival numbers reported in the JAMA article. Today, a large number of commercial laboratories offer these tests as part of standard panels. And, like k-ras mutations in colon cancer or BCR-abl in CML (the target of Gleevec), the arguments in favor of the use of these analyses is strong.

Non-small cell lung cancer

Non-small cell lung cancer

But what of the NSCLC patients for whom no clear identifiable driver can be found? What of the 25% with k-ras mutations for whom no drug exists? What of those with complex mutational findings? And finally what of those patients whose tumors are driven by normal genes functioning abnormally? In these patients no mutations exists at all. How best do we manage these patients?

I was reminded of this question as I reviewed a genomic analysis reported to one of my colleagues. He had submitted a tissue block to an east coast commercial lab when one of his lung cancer patients relapsed. The results revealed mutations in EGFr L858R & T790M, ERBB4, HGF, JAK2, PTEN, STK11, CCNE1, CDKN2A/B, MYC, MLL2 W2006, NFKB1A, and NKX2-1. With a tumor literally bristling with potential targets, what is a clinician to do? How do we take over a dozen genetically identified targets and turn them into effective treatment strategies? In this instance, too much information can be every bit as paralyzing as too little.

Our preferred approach is to examine the small molecule inhibitors that target each of the identified aberrancies in our laboratory platform. We prefer to drill down to the next level of certainty e.g. cellular function. After all, the presence of a target does not a response make.

In this patient I would conduct a biopsy. This would enable us to examine the drugs and combinations that are active against the targets. A “hit” by the EVA-PCD assay would then isolate the “drivers” from the “passengers” and enable the clinician to intelligently select effective treatments. Combining genomic analyses with functional profiling (phenotypic analyses) provides the opportunity to turn speculative observations into actionable events.

This is the essence of Rational Therapeutics.

Pigment, Color and Cancer

An interesting story reported by National Public Radio on November 12 described the origins of color in biology. Andrew Parker, a biologist from London’s Natural History Museum, described the development of sightedness in living organisms.

Until 600 million years ago animals were sightless. Then predatory organisms developed vision and used it to pursue prey. From that point color became an integral part of biological existence. Colors could attract mates, serve as camouflage, protect against predators and attract other organisms such as pollinating bees.

One of the more interesting aspects of the discussion was the fact that vertebrates have no capacity to produce the color blue. Indeed green is also quite difficult. So how, one might ask, do butterflies, peacocks and people with blue eyes create the appearance of the color blue? The answer is quite interesting and may be instructive when we examine other biological phenomena.

Pigments, known as biochromes, are substances produced by living organisms that have the capacity to absorb or reflect light o220px-Lightmatter_flamingo2f specific wavelengths. Their chemical structure captures the energy of the light wave resulting in the excitation of electrons to higher energy states. Among the colors commonly found are heme porphyrins, chlorophyll, carotenoids, anthocyanins, and betalains. While it is comparatively easy for plants to produce a broad spectrum of colors, animals have a more limited palate. They can borrow pigments from other species, like the flamingo whose pink hue is borrowed from the shrimp it eats. It seems however, that blue and green pose unique problems and must be created through an ingenuous melding of chemical biochromes and what is known as “structural pigmentation.”

The wings of a bluebird or those of a Morpho butterfly use specialized structures that are capable of capturing light at just the right angle. In so doing, they selectively reflect light and combine specific wavelengths with chemical pigments to create the illusion of color. Blue butterflies and green parrots are, in reality, sophisticated illusionists.

So what of other biological phenomena, specifically cancers? Quite a lot it seems. We have come to think of cancer as a product of genetic information. Our linear thinking with origins in cancer biology dating to the 1950s has long held that biological phenomena reflect the presence (or absence) of genes. The principal known as Central Dogma dictated that DNA produced RNA, that RNA produced protein and that protein produced function.

Our tidy principles were dealt their first blow by the discovery of epigenetics and then by small interfering RNAs. Most recently noncoding DNAs have further clouded the picture. It seems that the behavior of cancers may be every bit as deceptive as the bright blue hue that we ascribe to our avian and insect brethren.

Like butterflies or birds, cancers cloak themselves in a mixture of genetic and structural elements. While their behavior may appear to reflect genetic aberrancies, it may be structural (e.g. micro-environmental) perturbations that confer their unique biology. One can no more grind up and extract a parrot’s wings to find blue pigment than can we grind up and extract the genetic information of cancer to recreate its cobrilliance-clipart-canstock1498651mplexity. This however has not prevented the reductionists among us from trying. Unfortunately for them, cancers are demonstrably more complex than their genetic makeup.

Like a bird or a butterfly we must witness the creature in its entirety to grasp its function and behavior. Genomic analyses conducted in a vacuum cannot define the complexity of cancer biology. To create successful cancer treatment outcomes, we need to determine cellular phenotype. And, the EVA-PCD assay is quintessentially phenotypic. This is why the functional profile resulting from the EVA-PCD assay can identify accurate targets and select therapies.

The Cost of Chemotherapy Comes Home to Roost

NY TImes rotatedMedical care in the United States is a $2.7 trillion industry. That translates into almost $8,000 per person per year. One of the most expensive aspects is cancer care. This has caught the attention of the medical oncology community. A highly touted editorial in the October, 2012 New York Times described the unwillingness of physicians at Memorial Sloan Kettering Cancer Center to add a new and expensive drug to their formulary. The authors opined that the new drug provided outcomes similar to those for an existing drug, yet cost twice the price.

A subsequent editorial in the Journal of Clinical Oncology from MD Anderson (Cancer Drugs in the United States: Justum Pretium – The Just Price) further examined the cost of cancer therapy, profit margins and some of the drivers. Among the points raised was the fact that the monthly cost of chemotherapy had more than doubled from $4,500 to $10,000 in just one decade. Furthermore, of twelve anticancer drugs approved in 2012, only three prolonged survival and for 2 of 3 by less than two months. Despite these marginal benefits, nine of the twelve drugs were priced at more than $10,000 a month.
60 Minutes
This caught the attention of the media with 60 Minutes recently conducting an interview with the authors of the New York Times editorial. While Lesley Stahl pointedly decried the rather marginal 4 – 6% markups that many physicians apply to cover their costs of chemotherapy drug administration, there are in fact much darker forces at work.

The cost of cancer drug development reflects the expense of human subject trials, cost of R & D, the regulatory burden, as well as an extraordinary new drug failure rate. Fully 50% of new agents fail at Phase III (the last and most expensive type of study). Phase III trials cost tens to hundreds of millions of dollars. An article in Forbes magazine stated that the average drug approved by the FDA now costs, not the one billion dollars often cited but instead five billion dollars when one factors in the failures against the rare successes.

Drug development begins with a novel idea, a small molecule and a few preliminary results. At this point the expenses are low but the drug is of little commercial value. As one moves from cell lines to animal models, the price goes up but the value remains low. The cost of formulation, toxicology and animal studies continue to add up but doesn’t influence interest in the agent. Then come human studies as the Phase I trials begin. Specialized institutions across the United States accept contracts with the pharmaceutical industry to examine the tolerability of the drug. I use that term advisably as the intent of Phase I trials is only to determine safety not efficacy. If the drug proves tolerable, it then moves to Phase II to explore it’s activity against cancer. This is where the money starts flowing.

Phase II clinical trials are conducted by university medical centers. Each patient accrued costs the pharmaceutical sponsors from $25,000 to more than $50,000 per patient. As drugs are tested in many schedules against many diseases it can take hundreds or even thousands of patients for statistical analysis. Nonetheless, a successful Phase II trial showing meaningful benefit in a cancer population generates a buzz and the drug’s value begins to gain traction. With hundreds of millions already expended, the final testing pits the new drug against an existing standard in one or more Phase III trials. Endpoints like progression-free-survival must then fold into overall survival if the drug has any hope to gain full approval by the FDA. These registration triaus-money-with-black-backdrop-1024x640ls at the national or international Phase III level cost up to $100,000 per patient and most of the participating institutions are university-based medical centers or their affiliates.

So, why do chemotherapy drugs cost so much? While it may be convenient to point fingers at the pharmaceutical industry, private practitioners or the smaller institutions, the university medical centers and their affiliates have added greatly to the costs of drug development as have the increasingly byzantine regulatory standards that have so encumbered the process that it is now increasingly only a rich man’s game.

We applaud the investigators at Memorial Sloan-Kettering for focusing attention upon this important matter. We applaud 60 Minutes and the authors of the Journal of Clinical Oncology editorial for their exploration of the same. While the willingness of these physicians to raise the issue is laudable, the solution may be somewhat more complex than these authors have been willing to admit. Before we vilify private practitioners who have time and again proven to be more efficient and less expensive purveyors of cancer care than their university brethren we should examine other drivers.

To wit, a review of one of the NY Times editorial author’s conflicts of interest statement listed in the 2012 American Society of Clinical Oncology proceedings revealed that his co-presenters at this national meeting disclosed fully 16 separate pharmaceutical affiliations for employment or leadership positions, consultant or advisory roles, stock ownership, honoraria, research funds, expert testimony, or other remuneration. With the research community enjoying these levels of compensation, it must be surmised that the costs of clinical trials reflect in part these expenditures. When one adds to this, the increasingly burdensome regulatory environment, the cost of cancer chemotherapy development appears to have plenty of blame to go around.

Future (Cancer) Shock

Two related clinical trials were reported in the last several months describing the use of heat shock protein 90 (HSP90) inhibitors in lung cancer. Both trials fell short of their pre-specified endpoints casting a pall upon these drugs. However, the study of HSP90 inhibitors should not be abandoned based on these finding, as this is a fertile area of investigation and offers opportunities for the future.

Human cells marshal many defenses against stress. Thermal injury can damage basic cellular functions by denaturing (inactivating) proteins. The machinery of cells is largely comprised of protein enzymes. Excessive heat coagulates proteins much the way the albumin of an egg turns white during cooking. The loss of fluidity and function ultimately results in cell death. The heat shock proteins come to the rescue by shepherding these proteins away from injury and protecting them from denaturation.

220px-Hsp90There are many different heat shock proteins found in human cells, but one of the most abundant and active in cancer cells is known as HSP90 for its molecular weight in the range of 90-kilodaltons. Over the last two decades investigators have explored the use of small molecules to inhibit these important proteins. Among the first compounds to be isolated and applied were derivatives of geldenamycin. Although geldenamycin itself is a poison that causes severe liver damage, its derivative 17-AAG, also known as tanespimycin, has successfully entered clinical trials.

The current studies examined two other HSP90 inhibitors. One retaspimycin, has been developed by Infinity Pharmaceuticals. This clinical trial combined retaspimycin with docetaxel and compared results with docetaxel alone in 226 patients with recurrent lung cancer. None of the patients had received docetaxel prior to the trial. Drugs were administered every three weeks and the efficacy endpoint was survival with a subset analysis focused on those with squamous cell cancer. The trial fell short of its pre-designated endpoint. Interestingly, the study failed to provide benefit even in patients who were specifically targeted by their tumor’s expression of the K-Ras, p53 or by elevated blood levels of HSP90, the putative biomarkers for response.

The second trial examined a different HSP90 inhibitor developed by Synta Pharmaceuticals. The drug ganetespib was combined with docetaxel and the combination was compared with docetaxel alone. The results just reported indicate that the combination provided a median survival of 10.7 months, while docetaxel alone provided a median survival of 7.4 month. Although this represented a three month improvement, it did not meet the pre-specified target.

Taken together, these results could dampen enthusiasm for these agents. This would be unfortunate, for this class of drugs is active in a number of human tumors. We observed favorable activity and synergy for the HSP90 inhibitor geldenamycin and its derivative 17-AAG as we reported (Nagourney RA et al Proc. AACR, 2005). More importantly, 17-AAG (tanespimycin) provided objective responses in 22% and clinical benefit in 59% of patients with recurrent HER2 positive breast cancer after these patients had failed therapy with Herceptin. This clearly supports the role of HSP90 inhibition in breast cancer and would suggest that other more carefully selected target diseases could benefit as well.

The function of HSP90 is not completely understood as it influences the intracellular trafficking of dozens ofHsp90cycle proteins. One of the complexities of this class of drugs is that they protect and enhance the function of both good and bad proteins. After all, the HSP90 protein doesn’t know which proteins we, as cancer doctors, would like it to protect.

When we apply the EVA-PCD analysis to these and related classes of compounds we focus our attention upon the downstream effects, namely the loss of cell survival. That is, whatever proteins are influenced, the important question remains “did that effect cause the cells to die?” Classes of compounds with nonspecific targets like the HSP90 inhibitors will surely be the most difficult to characterize at a genomic or proteomic level: What protein? What gene?

Functional platforms like the EVA-PCD offer unique opportunities to study these classes of agents. We are convinced that the HSP90 inhibitors have a role in cancer therapy. It would be unfortunate if these setbacks led us to “throw the baby out with the (hot) bathwater,” thus slowing or preventing their use in cancer treatment.

A Tribute to Loretta Stamos 1939 – 2014

RAN & Loretta cropped lo res

Dr. Nagourney and Loretta Stamos

On Monday, September 22, 2014, we lost a great ally and a better friend.

Loretta Stamos lost her own fight with cancer, the very disease that she had worked so tirelessly to defeat. I first met Loretta in 1995 when her brother Jake was diagnosed with advanced lung cancer. His physicians didn’t offer much hope. At our meeting, I explained my approach to cancer therapy using each patient’s cells to select drugs (EVA-PCD functional profile).

“Let’s do it,” said Loretta.

“Now?” I asked.

“Why not?” she replied. As I would come to know over our 20 year friendship, Loretta didn’t mince words and was not one to take no for an answer.

A simple two drug combination was recommended for Jake, but his physicians declined. Loretta asked if I would assume his care. As I was out-of-network for his HMO, each time we treated her brother, Loretta generously covered the chemotherapy costs. After two cycles of treatment, the pleural fluid stopped accumulating. Jake gained weight and returned to some of his normal activities.

The in-network physicians began to realize that they were on the wrong side of this equation and suddenly offered to continue the treatments at their facility. Jake’s cancer ultimately progressed. His extensive metastatic disease involving his lung and bones was too aggressive for even the best chemotherapy to cure. Despite the sad loss, we had succeeded in showing that every patient deserved the chance to get better regardless of their insurance or finances.

Loretta wondered what would have happened if she had not been there to help. I explainRAN_LS_JS2 lo resed that the laboratory analyses were too costly for me to donate. Though they came in at a fraction of the price of a single dose of chemotherapy, many insurers refused to cover them. Loretta said, “I’m going to make sure that people who need these tests will never be denied.” And the Vanguard Cancer Foundation (VCF) was born.

Months of work, committee meetings and planning sessions culminated in a “A Night in Brazil,” a gala benefit that raised $100,000. John Stamos, Dave Coulier and Bob Saget turned in stellar performances as the MCs and a great time was had by all. More importantly, for the first time we could to say to patients, “We can find the treatment that’s right for you and if you can’t afford it, we’ll give it to you.” With each passing year the fund grew as did the number of patients we could help.

John and Loretta Stamos w-Sarah AmentoWhat a luxury to never turn a patient away. What an opportunity to help uninsured and younger patients. What a pleasure to see the good responses, even in some patients considered previously “untreatable.” I was overwhelmed by Loretta’s dedication and the kindness that she and the VCF members showed to patients in need. Every year we would recognize Loretta and her family for their hard work and generous contributions, and every year Loretta would say that she did this because “I made her brother smile.”

There is a silver lining to even the darkest cloud. It was Loretta who put it most poignantly when she defined the mission of the Vanguard Cancer Foundation as providing lifesaving care to “persons of worth but not of means.” The most fitting tribute of all for this noble soul is the more than 400 patients who can thank Loretta Stamos for a second chance at life.

New Diagnostic Test for the Early Detection of Lung Cancer

I was invited to discuss a new diagnostic test for the early detection of lung cancer by Gerri Willis of Fox Business News’ Willis Report.
An Italian clinical study presented at the September 2014 European Respiratory Society described 82 patients with abnormal chest x-rays. Patients breathed into a machine that measured the temperature of the exhaled air. Forty of the patients ultimately proved to have cancer and 42 did not, as confirmed by subsequent biopsy. They found a correlation between the temperature of the exhaled breath and presence of lung cancer. They also found that long term smokers had higher breath temperatures, as did those with higher stage disease.

For a variety of reasons, a test as simple as breath temperature seems unlikely to be highly specific. After all, the temperature of the exhaled breath could reflect infection, inflammation, or even activity level, as vigorous exercise can raise the body’s core temperature. Nonetheless, the fact that there is any correlation at all is of interest.

PET scan lung cancerWhat might underlie these findings? Accepting the shortfalls of this small study, it is an interesting point of discussion. First, cancer is a hyper metabolic state. Cancers consume increased quantities of glucose, proteins, and lipids. PET scans measure these phenomena every day. Second, cancer is associated with hyper vascularity. Up-regulation of VEGF could cause hyperemia (increased capillary blood flow) in the airways of lung cancer patients, resulting in the finding. Finally, cancer, in and of itself, is an inflammatory state. Inflammation reflects increased metabolic activity that could manifest as a whole body change in basal temperature.

Lung cancer is the leading cause of cancer death in the US, constituting 27% of all cancer deaths. Despite the over 224,000 new diagnoses and 160,000 deaths, the five-year survival for lung cancer today at 17% has not changed in several decades. Nonetheless patients who are detected early (Stage I) have a greater than 50% five-year survival.

We know from the National Lung Cancer Screening Trial published in 2010, that early detection by CT scans can reduce mortality from this disease by 20%. In the cancer literature, that is huge. The problem is that screening CTs are comparatively expensive, inconvenient, expose patients to radiation and are themselves fraught with false positives and false negatives. Furthermore, it is estimated that that broad application of spiral CT’s could cost over $9 billion a year. Thus, simple, non-invasive screening techniques are sorely needed.

The use of exhaled breath to diagnose cancers has been under in development for decades. Recently, investigators from The Cleveland Clinic and others from Israel have reported good results with a microchip that measures the concentration of volatile organic compounds in the breath and provides a colorimetric score. With several hundred patients the receiver-operating curves (ROC, a technique that gauges the sensitivity and specificity of a test) in the range of 0.85 (1.0 is perfect) are quite favorable. Although these techniques have not yet gained broad application, they are extremely interesting from the standpoint of what it is they are actually measuring.

For decades, the principal focus of scientific exploration in cancer has been genomic. Investigators at Boston University and others at MD Anderson in Texas have used genomic and methylation status of oro-and naso-pharyngeal swabs to identify the earliest hallmarks of malignant transformation. To the contrary, the breath tests described above measure phenomena that fall more in the realm of metabolomics. After all, these are measures of cellular biochemical reactions and identify the transformed state at a metabolic level.

Though still in its infancy, metabolomics reflects the most appealing of all cancer analyses. Examining cancer for what it is, rather than how it came to be, uses biochemistry, enzymology and quantitative analyses. These profile the tumor at the level of cellular function. Like the platforms that I utilize (EVA-PCD), these metabolic analyses examine the tumor phenotype.

I applaud these Italian investigators for using a functional approach to cancer biology. This is a highly productive direction and fertile ground for future research. Will breath temperature measurement prove sensitive and specific enough to diagnose cancer at early stage? It is much too early to say, but at least for now, I wouldn’t hold my breath.

Expert Advice – Another Wrinkle

Few dictates of modern medicine could be considered more sacrosanct than the prohibition of excess salt intake in our daily diets. For more then five decades every medical student has had the principle of dietary salt reduction drummed into his or her heads. Salt was the bane of human health, the poison that created hypertension, congestive heart failure, stroke, renal failure and contributed to the death of untold millions of people in the western society. At least so it seemed.

Three articles in the 08/14/2014 New England Journal of Medicine raise serious questions about the validity of that heretofore established principle of medical therapeutics.

Two of the articles utilized urinary sodium and potassium excretion as a surrogate for dietary intake to examine impact on blood pressure, mortality and cardiovascular events overall. A third article applied a Bayesian epidemiologic modeling technique to assess the impact of sodium intake on cardiovascular mortality.

salt shaker-nihThe first two articles were unequivocal. Low sodium intake, that is, below 1.5 to 2 grams per day was associated with an increase in mortality. High sodium intake that is, greater than 6 grams per day, was also associated with an increase in mortality; but the middle ground, that which reflects the usual intake of sodium in most western cultures did not pose a risk. Thus, the sodium intake associated with the western diet was safe. What is troubling however is the fact that very low sodium diets, those promulgated by the most established authorities in the field, are in fact hazardous to our health.

It seems that every day we are confronted with a new finding that refutes an established dogma of modern medicine. I have previously written blogs on the intake of whole milk or consumption of nuts, both of which were eschewed by the medical community for decades before being resurrected as healthy foodstuffs in the new millennium. One by one these pillars of western medicine have fallen by the wayside. To this collection, we must now add the low-salt diet.

Thomas Kuhn in his 1962 book, The Structure of Scientific Revolutions, stated that a new paradigm would only succeed if a new one arises that can replace it. Perhaps these large meta-analyses will serve that purpose for sodium intake and health. One can only wonder what other medical sacred cows should now be included in these types of inquiries?

As a researcher in the field of human tumor biology and purveyor of the EVA-PCD platform for prediction of chemotherapy drug response and oncologic discovery, I am intrigued but also encouraged, by the scientific community’s growing ability to reconsider its most established principles as new data forces a re-examination of long held beliefs. It may only be a matter of time before more members of the oncologic community re-examine the vast data supporting the predictive validity of these Ex Vivo Analyses and come to embrace these important human tumor phenotypic platforms. At least we can hope so.

Toward A 100% Response Rate in Human Cancer

Oncologists confront numerous hurdles as they attempt to apply the new cancer prognostic and predictive tests. Among them are the complexities of gene arrays that introduce practicing physicians to an entirely new lexicon of terms like “splice variant, gene-rearrangement, amplification and SNP.”

Althougcancer for dummiesh these phrases may roll of the tongue of the average molecular biologists (mostly PhDs), they are foreign and opaque to the average oncologist (mostly MDs). To address this communication shortfall laboratory service providers provide written addenda (some quite verbose) to clarify and illuminate the material. Some institutions have taken to convening “molecular tumor boards” where physicians most adept at genomics serve as “translators.” Increasingly, organizations like ASCO offer symposia on modern gene science to the rank and file, a sort of Cancer Genomics for Dummies. If we continue down this path, oncologists may soon know more but understand less than any other medical sub-specialists.

However well intended these educational efforts may be, none of them are prepared to address the more fundamental question: How well do genomic profiles actually predict response? This broader issue lays bare our tendency to confuse data with results and big data with big results. To wit, we must remember that our DNA, originally provided to each of us in the form of a single cell (the fertilized ovum) carries all of the genetic information that makes us, us. From the hair follicles on our heads to the acid secreting cells in our stomach, every cell in our body carries exactly the same genetic data neatly scripted onto our nuclear hard-drives.
What makes this all work, however, isn’t the DNA on the hard drive, but instead the software that judiciously extracts exactly what it needs, exactly when it needs it. It’s this next level of complexity that makes us who we are. While it is true that you can’t grow hair or secrete stomach acid without the requisite DNA, simply having that DNA does not mean you will grow hair or make acid. Our growing reliance upon informatics has created a “forest for the trees” scenario, focusing our gaze upon nearby details at the expense of larger trends and insights.

What is desperately needed is a better approximation of the next level of complexity. In biology that moves us from the genotype (informatics) to the phenotype (function). To achieve this, our group now regularly combines genomic, transcriptomic or proteomic information with functional analyses. This enables us to interrogate whether the presence or absence of a gene, transcript or protein will actually confer that behavior or response at the system level.

I firmly believe that the future of cancer therapeutics will combine genomic, transcriptomic and/or proteomic analyses with functional (phenotypic) analyses.

Recent experiences come to mind. A charming patient in her 50s underwent a genomic analysis that identified a PI3K mutation. She sought an opinion. We conducted an EVA-PCD assay on biopsied tissue that confirmed sensitivity to the drugs that target PI3K. Armed with this information, we administered Everolimus at a fraction of the normal dose. The response was prompt and dramatic with resolution of liver function abnormalities, normalization of her performance status and a quick return to normal activities. A related case occurred in a young man with metastatic colorectal cancer. He had received conventional chemotherapies but at approximately two years out, his disease again began to progress.

A biopsy revealed that despite prior exposure to Cetuximab (the antibody against EGFR) there was persistent activity for the small molecule inhibitor, Erlotinib. Consistent with prior work that we had reported years earlier, we combined Cetuximab with Erlotinib, and the patient responded immediately.

Each of these patients reflects the intelligent application of available technologies. Rather than treat individuals based on the presence of a target, we can now treat based on the presence of a response. The identification of targets and confirmation of response has the potential to achieve ever higher levels of clinical benefit. It may ultimately be possible to find effective treatments for every patient if we employ multi-dimensional analyses that incorporate the results of both genomic and phenotypic platforms.


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