KRAS is one of the most frequently mutated human oncogenes. In spite of mounting efforts on the development of direct or indirect inhibition targeting KRAS, little has been achieved because of insurmountable difficulties, titling KRAS "undruggable". Recently, subtype-specific inhibitors have shown great hope. Some KRAS^G12C inhibitors have entered clinical trials, including adagrasib and sotorasib, and have shown preliminary clinical effectiveness. Experiences from the inhibitors targeting the downstream factors of RAS pathways show that the anticancer activity of these drugs will be limited due to the development of drug resistance. Preclinical studies of KRAS^G12C inhibitors have revealed that the application of these agents might be hampered by the drug resistance issue. The current review aims to describe the current status of KRAS^G12C inhibitors, and discuss the mechanisms underlying KRAS^G12C inhibitor resistance, so as to provide the clues for the combat of drug resistance.

OBJECTIVETo explorer the effectiveness of enriched bone marrow stem cells technique for lumbar fusion.

METHODSWith the randomization and control principles, 2 graft materials [Enrichment bone marrow mesenchymal stem cells hybridized with beta-tri calcium phosphate (composite graft group), autologous iliac crest bone graft (autograft group)] were compared in posterior lumbar fusion procedures. 56 patients with degenerative disc disease, lumbar instability or spinal stenosis, were included. The volume of cells suspension in pre- and post-enrichment and the number of nucleated cells (NCs) were identified. The number of osteoprogenitor cells was estimated by counting the colony-forming units which express alkaline phosphatase (CFUs/ALP+). Then the efficiency of the enrichment was evaluated. Clinical follow-up with roentgenogram and Oswestry scale scores was performed for outcome evaluation.

RESULTS(249 +/- 31) ml bone marrow per patient from bilateral iliac crests was aspirated peri-operatively. About (43 +/- 11) ml enriched bone marrow was collected. The number of NCs was concentrated from (15.9 +/- 3.3) x 10(6)/ml to (44.1 +/- 10.8) x 10(6)/ml, CFUs/ALP+ was significantly increased from (118 +/- 86)/ml to(486 +/- 305)/ml. The follow-up was about (26.3 +/- 7.5) months. There was no significant differences in age, gender, disease and fusion segments between the two groups. The fusion rate was 93.3% and 96.2% for composite graft group and autograft group, respectively (chi2 = 0.2146, P = 0.6432). There was no difference in operation time between the two group (t = 0.5243, P = 0.6022), but blood loss in composite graft group was more than that in autograft group (t = 6.4664, P < 0.01). Cell salvage for auto-transfusion could transfuse back half of the blood loss during operation. No hematoma or chronic soreness in the bone marrow donor sites of composite graft group occurred, but a little exudation or moderate swelling in the wound happened in 4 cases which disappeared under medical treatment. Meanwhile, 15.4% patients had hematoma in the iliac bone donor site and 26.9% patients had chronic soreness, but no case had wound problem in autograft group. As for Oswestry scale scores, there was no significant difference between the two groups.

CONCLUSIONSThe enrichment technique of autologous bone marrow stem cells can greatly increase the concentration of MSCs. It is a rapid and safe method used peri-operatively. The composite material of enriched MSCs and porous beta-TCP is a good bone substitute in posterior spinal fusion.

Adult ; Aged ; Bone Substitutes ; Bone Transplantation ; methods ; Calcium Phosphates ; Female ; Follow-Up Studies ; Humans ; Ilium ; transplantation ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Spinal Fusion ; instrumentation ; methods ; Stem Cell Transplantation ; Transplantation, Autologous ; Treatment Outcome

Objective To explore the association of cardiac disease associated genetic variants and the high incidence of Yunnan sudden unexplained death （YNSUD） in Yi nationality. Methods The genomic DNA was extracted from peripheral blood samples collected from 205 Yi villagers from YNSUD aggregative villages （inpatient group） and 197 healthy Yi villagers from neighboring villages （control group）. Fifty-two single nucleotide variants （SNVs） of 25 cardiac disease associated genes were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. The SPSS 17.0 was used to analyze data. The pathogenicities of variants with differences between the two groups that have statistical significance were predicted by protein function prediction software PolyPhen-2 and SIFT. All villagers from inpatient group were given electrocardiogram （ECG） examination using a 12-lead electrocardiograph. Results The allele frequency and the genotype frequency of missense mutation DSG2 （rs2278792, c.2318G>A, p.R773K） of pathogenic genes of arrhythmogenic right ventricular cardiomyopathy （ARVC） in inpatient group was higher than that in control group （P<0.05）. Abnormal ECG changes were detected in 71 individuals （34.6%） in the inpatient group, among which 54 individuals carried R773K mutation, including clockwise （counterclockwise） rotation, left （right） axis deviation, ST segment and T wave alteration and heart-blocking. Conclusion Definite pathogenic mutations have not been found in the 52 cardiac disease genes associated SNVs detected in Yi nationality in regions with high incidence of YNSUD. The cause of high incidence of YNSUD in Yi nationality needs further study.
Arrhythmogenic Right Ventricular Dysplasia ; China/epidemiology* ; Death, Sudden/etiology* ; Death, Sudden, Cardiac/etiology* ; Ethnicity/genetics* ; Humans ; Incidence ; Mutation

Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; Genetic Predisposition to Disease ; Hearing Loss, Noise-Induced ; genetics ; Humans ; NF-E2-Related Factor 2 ; genetics ; Occupational Exposure

Adult ; Air Pollutants, Occupational ; adverse effects ; Benzene ; adverse effects ; Blood Cell Count ; Commerce ; Environmental Monitoring ; Female ; Hemoglobins ; analysis ; Humans ; Male ; Middle Aged ; Occupational Exposure ; adverse effects ; Ownership