An experimental drug could help control some melanomas that have BRAF or NRAS mutations, according to a report at an American Society of Clinical Oncology meeting. Tumors shrank or did not get worse in 8 out of 35 patients with the most common BRAF mutation (V600E), and in 6 out of 28 patients with NRAS mutations. This is the first targeted treatment for melanomas that have NRAS mutations. BRAF and NRAS mutations can activate a protein called MEK that is involved in cell division. The experimental drug, which is called MEK162, is a MEK inhibitor. The side effects of MEK162, which included diarrhea, rashes and swelling, were manageable.
An early stage clinical trial suggests that dabrafenib, a BRAF inhibitor, could treat melanomas that have spread to the brain. The study, reported in The Lancet, included 10 people with brain metastases of melanomas that had BRAF mutations. Tumors shrank in 9 patients and were not evident in 4 patients. This is a surprise because the drug had not been expected to cross the blood-brain barrier effectively. Indeed, melanoma patients with brain metastases have been routinely excluded from previous trials of vemurafenib (Zelboraf) and other BRAF inhibitors.
A New England Journal of Medicine study reports a promising new approach to treating melanomas with BRAF mutations, which often respond to BRAF inhibitors for just a short time. Melanoma patients treated with trametinib were stable (ie, did not get worse) for three times longer than those treated with dacarbazine, a conventional chemotherapy drug (4.8 vs. 1.5 months, respectively). Trametinib inhibits MEK, a protein that is activated by BRAF and is involved in cell division. The drug’s most common side effects were rash, diarrhea, and swelling in the legs, which could be controlled by periodically adjusting the dose.
Primary source: http://www.nejm.org/doi/full/10.1056/NEJMoa1203421
Researchers identified a new mutation (BRAF L597) in a melanoma patient and then tested for it in 49 other melanomas that had no known cancer-linked mutations, which account for about half of all melanomas. They found that BRAF L597 occurred in 4% of the other melanomas tested. The study, which appeared in Cancer Discovery, also showed that tumors with this mutation respond to a MEK inhibitor called TAK-733. The existence of a targeted treatment, coupled with the new mutation’s relatively high incidence, lead the researchers to suggest routinely screening melanomas for BRAF L597.
Bevacizumab (Avastin), which is approved for treatment of a number of advanced-stage cancer types, is commonly avoided in patients with brain metastases (cancer that has spread to the brain) because of fear of brain hemorrhages (bleeding in the brain). A retrospective study of 52 patients with advanced non-small cell lung cancer (NSCLC) who had received chemotherapy containing Avastin found no cases of serious bleeding events and no significant differences in survival or treatment side effects between patients with or without brain metastases. Avastin may therefore be a safe treatment option in NSCLC with brain metastases.
Research paper: https://www.jstage.jst.go.jp/article/acrt/20/2/20_47/_pdf
The roles of the genes IGF1R and EGFR in lung cancer were examined in patients with non-small cell lung cancer (NSCLC) who had their primary tumor surgically removed. Patients whose tumors had increased expression of both IGFR1R and EGFR were more likely to experience recurrence of the cancer after a shorter amount of time and had shorter survival times after surgery. This finding suggests that concurrent overexpression of IGF1R and EGFR is a negative prognosis factor in NSCLC and may indicate patients who are more likely to benefit from novel treatments with IGF1R inhibitors.
A retrospective study in Japan examined 55 patients aged 75 years or over with inoperable non-small cell lung cancer (NSCLC) who had a mutation in the EGFR gene and received gefitinib (Iressa) as first-line therapy. The treatment was generally well tolerated and patients experienced longer periods without cancer progression (median: 13.8 months) and longer overall survival (median: 29.1 months) than commonly reported for similar patients. While studies using control groups will need to confirm that Iressa is indeed more effective than standard chemotherapy or a placebo, these findings suggest that Iressa may be a preferable first-line treatment in elderly patients with advanced EGFR-mutant NSCLC.
A study of individuals with and without lung cancer in North India found that those carrying a particular version (or “polymorphism”) of a gene for the protein p53 were more likely to have lung cancer, independent of their age or smoking rate. P53 belongs to a class of proteins called “tumor suppressor proteins,” and is involved in DNA repair, regulating cell growth, and inducing cell death in damaged or abnormal cells. The findings suggest that this version of the p53 gene, called Arg72Pro, may contribute to higher susceptibility for lung cancer, at least in the North Indian population.
Research paper: http://online.liebertpub.com/doi/full/10.1089/dna.2012.1792
A recent study examined first-line treatment with the chemotherapy agent carboplatin (Paraplatin), combined with either albumin-bound paclitaxel (Abraxane) or standard solvent-based paclitaxel (Taxol), in both elderly and younger patients with advanced non-small cell lung cancer (NSCLC). Patients treated with Abraxane/Paraplatin exhibited higher treatment response rates and fewer toxic side effects in both age groups; elderly patients (age 70+ years) experienced longer periods without cancer progression and longer overall survival with Abraxane/Paraplatin compared to Taxol/Paraplatin treatment. Abraxane plus Paraplatin may constitute a safe, effective first-line treatment for elderly patients with advanced NSCLC, a group that has been traditionally undertreated.
Research paper: http://annonc.oxfordjournals.org/content/24/2/314.long