KRAS mutation in tumor tissue is a well-known predictor of resistance to the treatment of anti-EGFR antibodies in metastatic colorectal cancers (mCRC). However, the prognostic value of low-frequency plasma circulating tumor DNA (ctDNA) KRAS mutation in predicting treatment resistance in pretreated mCRC patients remains controversial. This study retrospectively reviewed the clinical course, including response to anti-EGFR and anti-VEGF therapies, and changes in serum tumor marker levels along with image studies in mCRC patients with <1.5% KRAS mutations detected in plasma ctDNA by next-generation sequencing (NGS) at a single center in Taiwan. We identified six pretreated mCRC patients with low-frequency KRAS G12V/G12D/G12S/G13D mutations (variant allele frequency 0.26~1.23%) in plasma ctDNA. Co-occurring low-frequency ctDNA mutations in APC, TP53, MAP2K1, KEAP1, or CTNNB1 were also detected. Although all six patients had treatment adjustments within one month after the ctDNA genetic test, image-evident tumor progression was noted in all patients within a median of 4 months afterwards. Re-challenge therapy with a combination of anti-EGFR, anti-VEGF, and FOLFIRI chemotherapy was found to be ineffective in a patient with 0.38% KRAS G12D mutation in baseline ctDNA. Our study suggests that the detection of low-frequency KRAS mutations in ctDNA could be used as a predictor of treatment response in mCRC patients.
Summary: Serum fatty acid (FA) levels were monitored in women with severe obesity during intensive lifestyle intervention. At baseline, total FA levels and most individual FAs were elevated compared to a matching cohort of normal and overweight women (healthy controls). After 3 weeks of intensive lifestyle intervention, total level was only 11–12% higher than in the healthy controls and with almost all FAs being significantly lower than at baseline, but with levels of omega‐3 being similar to the healthy controls. This is contrary to observations for patients subjected to bariatric surgery where omega‐3 levels dropped to levels significantly lower than in the lifestyle patients and healthy controls. During the next 3 weeks of treatment, the FA levels in lifestyle patients were unchanged, while the weight loss continued at almost the same rate as in the first 3 weeks. Multivariate analysis revealed that weight loss and change of serum FA patterns were unrelated outcomes of the intervention for lifestyle patients. For bariatric patients, these processes were associated probably due to reduced dietary input and increased input from the patients’ own fat deposits, causing a higher rate of weight loss and simultaneous reduction of the ratio of serum eicosapentaenoic to arachidonic acid.
Stress-induced myocardial perfusion defects found in dipyridamole–thallium-201 single-photon emission computed tomography imaging may indicate vascular perfusion abnormalities and risk of obstructive or nonobstructive coronary heart disease. Besides nuclear imaging and subsequent coronary angiography (CAG), no blood test can indicate whether dysregulated homeostasis is associated with stress-induced myocardial perfusion defects. This study investigated the expression signature of long noncoding RNAs (lncRNAs) and genes involved in vascular inflammation and stress response in the blood of patients with stress-induced myocardial perfusion abnormalities (n = 27). The results revealed an expression signature consisting of the upregulation of RMRP (p < 0.01) and downregulations of THRIL (p < 0.01) and HIF1A (p < 0.01) among patients with a positive thallium stress test and no significant coronary artery stenosis within 6 months after baseline treatment. We developed a scoring system based on the expression signatures of RMRP, MIAT, NTT, MALAT1, HSPA1A, and NLRP3 to predict the need for further CAG among patients with moderate-to-significant stress-induced myocardial perfusion defects (area under the receiver operating characteristic curve = 0.963). Therefore, we identified a dysregulated expression profile of lncRNA-based genes in the blood that could be valuable for the early detection of vascular homeostasis imbalance and personalized therapy.
11 March 2020 in Molecular Genetics & Genomic Medicine
Background: Congenital dyserythropoiesis anemia type Ia (OMIM:224120), is a rare hereditary anemia. The diagnosis is difficult to make and usually delayed in part due to its rarity and nonspecific clinical manifestations.Methods: Whole exome sequencing was applied for the genetic diagnosis of a 12‐year‐old boy who has suffered from hemolytic anemia since birth and who requires regular transfusions. Sanger sequencing of the variants detected in whole exome sequencing was performed in the patient and his parents.Results: Compound heterozygous mutations of CDAN1 gene, including one previously reported and one novel mutation, which is a splicing change, were detected in the whole exome sequencing and confirmed by Sanger sequencing. The autosomal recessive inheritance was confirmed by pedigree analysis.Conclusion: To our knowledge, this is the first case report of congenital dyserythropoiesis anemia type Ia with genetic diagnosis to be located in Taiwan. Because of the rarity of CDA Ia and the overlapping of the clinical manifestations with other hereditary anemias, the next‐generation sequencing approach is effective for conclusive diagnosis of CDA Ia.