UK Health Authority Issues Final Rejection for Cancer Drug Xalkori

The UK’s National Institute for Health and Clinical Excellence (NICE) confirmed its decision to reject using National Health Service funding to provide crizotinib (Xalkori) to patients. Xalkori is used for patients with previously treated non-small cell lung cancer (NSCLC) who have mutations in the ALK gene. While NICE acknowledges that Xalkori is effective in these patients, they do not consider its benefit substantial enough to warrant its high cost. Xalkori has been found to extend the time without cancer progression by an average of 5.1 months compared to standard chemotherapy; it is unclear whether it increases overall survival. UK patients can still take Xalkori, but would have to pay the full cost themselves (£37,512 – £51,579 for a complete treatment course).


Bypass Mechanisms of Resistance to Receptor Tyrosine Kinase Inhibition in Lung Cancer

“Receptor tyrosine kinases (RTKs) are activated by somatic genetic alterations in a subset of cancers, and such cancers are often sensitive to specific inhibitors of the activated kinase. Two well-established examples of this paradigm include lung cancers with either EGFR mutations or ALK translocations. In these cancers, inhibition of the corresponding RTK leads to suppression of key downstream signaling pathways, such as the PI3K (phosphatidylinositol 3-kinase)/AKT and MEK (mitogen-activated protein kinase kinase)/ERK (extracellular signal–regulated kinase) pathways, resulting in cell growth arrest and death. Despite the initial clinical efficacy of ALK (anaplastic lymphoma kinase) and EGFR (epidermal growth factor receptor) inhibitors in these cancers, resistance invariably develops, typically within 1 to 2 years. Over the past several years, multiple molecular mechanisms of resistance have been identified, and some common themes have emerged. One is the development of resistance mutations in the drug target that prevent the drug from effectively inhibiting the respective RTK. A second is activation of alternative RTKs that maintain the signaling of key downstream pathways despite sustained inhibition of the original drug target. Indeed, several different RTKs have been implicated in promoting resistance to EGFR and ALK inhibitors in both laboratory studies and patient samples. In this mini-review, we summarize the concepts underlying RTK-mediated resistance, the specific examples known to date, and the challenges of applying this knowledge to develop improved therapeutic strategies to prevent or overcome resistance.”


Bypass Mechanisms of Resistance to Receptor Tyrosine Kinase Inhibition in Lung Cancer

“Receptor tyrosine kinases (RTKs) are activated by somatic genetic alterations in a subset of cancers, and such cancers are often sensitive to specific inhibitors of the activated kinase. Two well-established examples of this paradigm include lung cancers with either EGFR mutations or ALK translocations. In these cancers, inhibition of the corresponding RTK leads to suppression of key downstream signaling pathways, such as the PI3K (phosphatidylinositol 3-kinase)/AKT and MEK (mitogen-activated protein kinase kinase)/ERK (extracellular signal–regulated kinase) pathways, resulting in cell growth arrest and death. Despite the initial clinical efficacy of ALK (anaplastic lymphoma kinase) and EGFR (epidermal growth factor receptor) inhibitors in these cancers, resistance invariably develops, typically within 1 to 2 years. Over the past several years, multiple molecular mechanisms of resistance have been identified, and some common themes have emerged. One is the development of resistance mutations in the drug target that prevent the drug from effectively inhibiting the respective RTK. A second is activation of alternative RTKs that maintain the signaling of key downstream pathways despite sustained inhibition of the original drug target. Indeed, several different RTKs have been implicated in promoting resistance to EGFR and ALK inhibitors in both laboratory studies and patient samples. In this mini-review, we summarize the concepts underlying RTK-mediated resistance, the specific examples known to date, and the challenges of applying this knowledge to develop improved therapeutic strategies to prevent or overcome resistance.”


Bypass Mechanisms of Resistance to Receptor Tyrosine Kinase Inhibition in Lung Cancer

“Receptor tyrosine kinases (RTKs) are activated by somatic genetic alterations in a subset of cancers, and such cancers are often sensitive to specific inhibitors of the activated kinase. Two well-established examples of this paradigm include lung cancers with either EGFR mutations or ALK translocations. In these cancers, inhibition of the corresponding RTK leads to suppression of key downstream signaling pathways, such as the PI3K (phosphatidylinositol 3-kinase)/AKT and MEK (mitogen-activated protein kinase kinase)/ERK (extracellular signal–regulated kinase) pathways, resulting in cell growth arrest and death. Despite the initial clinical efficacy of ALK (anaplastic lymphoma kinase) and EGFR (epidermal growth factor receptor) inhibitors in these cancers, resistance invariably develops, typically within 1 to 2 years. Over the past several years, multiple molecular mechanisms of resistance have been identified, and some common themes have emerged. One is the development of resistance mutations in the drug target that prevent the drug from effectively inhibiting the respective RTK. A second is activation of alternative RTKs that maintain the signaling of key downstream pathways despite sustained inhibition of the original drug target. Indeed, several different RTKs have been implicated in promoting resistance to EGFR and ALK inhibitors in both laboratory studies and patient samples. In this mini-review, we summarize the concepts underlying RTK-mediated resistance, the specific examples known to date, and the challenges of applying this knowledge to develop improved therapeutic strategies to prevent or overcome resistance.”


Mechanistic Insight into ALK Receptor Tyrosine Kinase in Human Cancer Biology

The burgeoning field of anaplastic lymphoma kinase (ALK) in cancer encompasses many cancer types, from very rare cancers to the more prevalent non-small-cell lung cancer (NSCLC). The common activation of ALK has led to the use of the ALK tyrosine kinase inhibitor (TKI) crizotinib in a range of patient populations and to the rapid development of second-generation drugs targeting ALK. In this Review, we discuss our current understanding of ALK function in human cancer and the implications for tumour treatment.


Cell – EGFR-Mediated Beclin 1 Phosphorylation in Autophagy Suppression, Tumor Progression, and Tumor Chemoresistance

Here, we defined the molecular basis by which the epidermal growth factor receptor (EGFR) tyrosine kinase regulates autophagy. Active EGFR binds the autophagy protein Beclin 1, leading to its multisite tyrosine phosphorylation, enhanced binding to inhibitors, and decreased Beclin 1-associated VPS34 kinase activity. EGFR tyrosine kinase inhibitor (TKI) therapy disrupts Beclin 1 tyrosine phosphorylation and binding to its inhibitors and restores autophagy in non-small-cell lung carcinoma (NSCLC) cells with a TKI-sensitive EGFR mutation.


Personalized Treatment Yields Results for Cancer Patients

Personalized cancer medicine uses genetic testing of patients’ tumors to guide individually tailored treatment decisions. Such tests can determine which chemotherapies would likely be most effective and whether the patient may benefit from novel drugs targeting specific mutations. One example is the case of Elizabeth Lacasia, who has advanced bronchioalveolar carcinoma, a type of non-small cell lung cancer (NSCLC). Testing revealed that she does not have any of the mutations targeted by the new drugs. Based on her test results, she was treated with a combination of Tarceva (erlotinib) and Alimta (pemetrexed) following an alternating schedule that has been proven effective for people with her cancer type. Her cancer has been in remission for 2 years.


More Lung Cancer Patients May Benefit from Xalkori Than Previously Thought

Xalkori (crizotinib) is very effective for most non-small cell lung cancer (NSCLC) patients with mutations in the ALK gene. However, new evidence suggests that current criteria for ALK mutation may be missing patients who could be treated with Xalkori. A recent study of NSCLC patients found that 8.5% had tumors that contained more than 10% cells with ALK mutations, but less than 15%, the current cut-off for ‘ALK-positive’ lung cancer. These patients may benefit from Xalkori or other ALK inhibitors. Moreover, some patients have atypical ALK mutations that are not detected by the standard test. A patient with such atypical ALK mutations profiled in a recent case study responded well to Xalkori treatment.


Molecular Marker Predicts Response to Iressa and Tarceva

A molecule named Mig 6 may help predict how much a patient will benefit from EGFR inhibitors like Tarceva (erlotinib) or Iressa (gefitinib). Preliminary results from an ongoing study reveal that cancer cells that are resistant to EGFR inhibitors have high Mig 6 levels. In an animal model of non-small cell lung cancer (NSCLC) without EGFR mutations, higher Mig 6 levels predicted more resistance to EGFR inhibitor treatment. Finally, NSCLC patients with low Mig 6 levels were more likely to survive for over a year after EGFR inhibitor treatments. Mig 6 may help identify patients who would most benefit from EGFR inhibitors.