UHMK1 promotes gastric cancer progression through reprogramming nucleotide metabolism.

UHMK1 is a nuclear serine/threonine kinase recently implicated in carcinogenesis. However, the functions and action mechanisms of UHMK1 in the pathogenesis of human gastric cancer (GC) are unclear. Here, we observed that UHMK1 was markedly upregulated in GC. UHMK1 silencing strongly inhibited GC aggressiveness. Interestingly, UHMK1-induced GC progression was mediated primarily via enhancing de novo purine synthesis because inhibiting purine synthesis reversed the effects of UHMK1 overexpression. Mechanistically, UHMK1 activated ATF4, an important transcription factor in nucleotide synthesis, by phosphorylating NCOA3 at Ser (S) 1062 and Thr (T) 1067. This event significantly enhanced the binding of NCOA3 to ATF4 and the expression of purine metabolism-associated target genes. Conversely, deficient phosphorylation of NCOA3 at S1062/T1067 significantly abrogated the function of UHMK1 in GC development. Clinically, Helicobacter pylori and GC-associated UHMK1 mutation induced NCOA3-S1062/T1067 phosphorylation and enhanced the activity of ATF4 and UHMK1. Importantly, the level of UHMK1 was significantly correlated with the level of phospho-NCOA3 (S1062/T1067) in human GC specimens. Collectively, these results show that the UHMK1-activated de novo purine synthesis pathway significantly promotes GC development.

Retracted: Upregulation of Serine Proteinase Inhibitor Clade B Member 3 (SERPINB3) Expression by Stromal Cell-Derived Factor (SDF-1)/CXCR4/Nuclear Factor kappa B (NF-κB) Promotes Migration and Invasion of Gastric Cancer Cells.

The Editors of Medical Science Monitor wish to inform you that the above manuscript has been retracted from publication due to concerns with the credibility and originality of the study, the manuscript content, and the Figure images. Reference: Jing Gong, Yongxi Song, Ling Xu, Xiaofang Che, Kezuo Hou, Tianshu Guo, Yu Cheng, Yunpeng Liu, Xiujuan Qu. Upregulation of Serine Proteinase Inhibitor Clade B Member 3 (SERPINB3) Expression by Stromal Cell-Derived Factor (SDF-1)/CXCR4/Nuclear Factor kappa B (NF-kB) Promotes Migration and Invasion of Gastric Cancer Cells. Med Sci Monit, 2020; 26: e927411. DOI: 10.12659/MSM.927411.

tRFTars: predicting the targets of tRNA-derived fragments.

BACKGROUND: tRNA-derived fragments (tRFs) are 14-40-nucleotide-long, small non-coding RNAs derived from specific tRNA cleavage events with key regulatory functions in many biological processes. Many studies have shown that tRFs are associated with Argonaute (AGO) complexes and inhibit gene expression in the same manner as miRNAs. However, there are currently no tools for accurately predicting tRF target genes. METHODS: We used tRF-mRNA pairs identified by crosslinking, ligation, and sequencing of hybrids (CLASH) and covalent ligation of endogenous AGO-bound RNAs (CLEAR)-CLIP to assess features that may participate in tRF targeting, including the sequence context of each site and tRF-mRNA interactions. We applied genetic algorithm (GA) to select key features and support vector machine (SVM) to construct tRF prediction models. RESULTS: We first identified features that globally influenced tRF targeting. Among these features, the most significant were the minimum free folding energy (MFE), position 8 match, number of bases paired in the tRF-mRNA duplex, and length of the tRF, which were consistent with previous findings. Our constructed model yielded an area under the receiver operating characteristic (ROC) curve (AUC) = 0.980 (0.977-0.983) in the training process and an AUC = 0.847 (0.83-0.861) in the test process. The model was applied to all the sites with perfect Watson-Crick complementarity to the seed in the 3' untranslated region (3'-UTR) of the human genome. Seven of nine target/nontarget genes of tRFs confirmed by reporter assay were predicted. We also validated the predictions via quantitative real-time PCR (qRT-PCR). Thirteen potential target genes from the top of the predictions were significantly down-regulated at the mRNA levels by overexpression of the tRFs (tRF-3001a, tRF-3003a or tRF-3009a). CONCLUSIONS: Predictions can be obtained online, tRFTars, freely available at http://trftars.cmuzhenninglab.org:3838/tar/ , which is the first tool to predict targets of tRFs in humans with a user-friendly interface.

The platelet to lymphocyte ratio is a potential inflammatory marker predicting the effects of adjuvant chemotherapy in patients with stage II colorectal cancer.

BACKGROUND: The effects of adjuvant chemotherapy in patients with stage II colorectal cancer (CRC) has been in controversy for a long time. Our study aimed to find an effective inflammatory marker to predict the effects of chemotherapy. METHODS: Seven hundred eight stage II CRC patients in our institution were included. The subpopulation treatment effect pattern plot (STEPP) analysis was used to determine the optimal inflammatory marker and cut-off value. Propensity score matching (PSM) was performed to balance discrepancy between the chemotherapy and non-chemotherapy group. Survival analyses based on overall survival (OS) and cancer-specific survival (CSS) were performed with Kaplan-Meier methods with log-rank test and Cox proportional hazards regression. The restricted mean survival time (RMST) was used to measure treatment effect. RESULTS: The platelet to lymphocyte ratio (PLR) was chosen as the optimal marker with a cut-off value of 130 according to STEPP. In OS analysis, PLR was significantly associated with the effects of chemotherapy (interaction p = 0.027). In the low-PLR subgroup, the chemotherapy patients did not have a longer OS than the non-chemotherapy patients (HR: 0.983, 95% CI: 0.528-1.829). In the high-PLR subgroup, the chemotherapy patients had a significantly longer OS than the non-chemotherapy patients (HR: 0.371, 95% CI: 0.212-0.649). After PSM, PLR was still associated with the effects of chemotherapy. In CSS analysis, PLR was not significantly associated with the effects of chemotherapy (interaction p = 0.116). In the low-PLR subgroup, the chemotherapy patients did not have a longer CSS than the non-chemotherapy patients (HR: 1.016, 95% CI: 0.494-2.087). In the high-PLR subgroup, the chemotherapy patients had a longer CSS than the non-chemotherapy patients (HR: 0.371, 95% CI: 0.212-0.649). After PSM, PLR was not associated with the effects of chemotherapy. CONCLUSIONS: PLR is an effective marker to predict the effects of chemotherapy in patients with stage II CRC.

Survival landscape of different tumor regression grades and pathologic complete response in rectal cancer after neoadjuvant therapy based on reconstructed individual patient data.

BACKGROUND: Neoadjuvant therapy can lead to different tumor regression grades (TRG) in rectal cancer after neoadjuvant therapy. The purposes of this study are to investigate the relationships among TRG, pathologic complete response (pCR) and long-term survival, on the basis of reconstructed individual patient data (IPD). METHODS: The PubMed, Embase, Ovid and Cochrane CENTRAL databases were searched. The primary endpoint was to evaluate the survival landscape of different TRGs after neoadjuvant therapy and the secondary endpoint was to evaluate the associations between pCR and survival. IPD were reconstructed with Kaplan-Meier curves. RESULTS: The 10-year overall survival (OS) and 5-year disease-free survival (DFS) were clearly higher in the pCR group than in the non-pCR (npCR) group (80.5% vs. 48.3, 90.1% vs. 69.8%). Furthermore, the OS and DFS increased with improvement in tumor regression after neoadjuvant therapy. According to the IPD, the pCR group had longer OS (HR = 0.240, 95% CI = 0.177-0.325, p < 0.001) and DFS (HR = 0.274, 95% CI = 0.205-0.367, p < 0.001) than the npCR group. Better tumor regression was associated with better survival outcomes (p < 0.005). Direct calculation of published HR values yielded similar results. CONCLUSIONS: Our results indicate a positive relationship between better tumor regressions and improved survival benefits among the npCR group and patients with rectal cancer achieving pCR had much longer OS and DFS than patients achieving npCR, presenting a survival landscape of different TRGs and pCR in rectal cancer after neoadjuvant therapy.

A 3'-tRNA-derived fragment enhances cell proliferation, migration and invasion in gastric cancer by targeting FBXO47.

Increasing evidence demonstrates that tRNA-derived fragments (tRFs) exert important effects and are dysregulated in various human cancer types. However, their roles in gastric cancer (GC) remain unknown. Here we identified the functional effects of tRF-3019a (derived from tRNA-Ala-AGC-1-1) in GC. We demonstrated that tRF-3019a was upregulated in GC tissues and cell lines. Phenotypic studies revealed that tRF-3019a overexpression enhances GC cell proliferation, migration and invasion. Conversely, tRF-3019a knockdown inhibits GC cell malignant activities. Mechanistic investigation implies that tRF-3019a directly regulates tumor suppressor gene FBXO47. Furthermore, tRF-3019a levels may discriminate GC tissues from nontumorous tissues. Taken together, our results reveal that tRF-3019a modulates GC cell proliferation, migration and invasion by targeting FBXO47, and it may serve as a potential diagnostic biomarker for GC.

Upregulation of Serine Proteinase Inhibitor Clade B Member 3 (SERPINB3) Expression by Stromal Cell-Derived Factor (SDF-1)/CXCR4/Nuclear Factor kappa B (NF-κB) Promotes Migration and Invasion of Gastric Cancer Cells.

BACKGROUND Serine proteinase inhibitor clade B member 3 (SERPINB3) is a neutral glycoprotein. Its overexpression is related to the promotion of cell proliferation and activation via the nuclear factor kappa B (NF-kappaB) pathway in several tumors. Whether it can participate in stromal cell-derived factor (SDF-1)/NF-kappaB-induced metastasis of gastric cancer has not been reported. MATERIAL AND METHODS We analyzed the ability of SDF-1 to induce migration and invasion in vitro by knocking down the expression of SERPINB3 with siRNAs in gastric cancer cells. We also explored the effects of a CXCR4 antagonist and NF-kappaB inhibitor on SERPINB3 expression. We verified the effect of SERPINB3 on prognosis in gastric cancer specimens by immunohistochemistry. RESULTS In vitro experiments confirmed that SDF-1 upregulated the expression of SERPINB3 and promoted metastasis in gastric cancer cells. This phenomenon was reversed by knockdown of SERPINB3, a chemokine receptor 4 (CXCR4) antagonist, and an NF-kappaB inhibitor, which downregulated the expression of SERPINB3. In patients with gastric cancer, a significant positive correlation was observed between CXCR4 and SERPINB3 expression (r=0.222, P=0.029). Moreover, double positivity for SERPINB3 and CXCR4 was certified to be an independent prognostic factor (HR=3.332, P<0.001). CXCR4-positive patients who also expressed SERPINB3 were inclined to suffer from lymph node metastasis, confirming that SERPINB3 is a downstream molecule of CXCR4. CONCLUSIONS In vitro and pathological results showed that SDF-1/CXCR4 activated the NF-kappaB pathway and upregulated SERPINB3 to facilitate the migration and invasion of gastric cancer cells.

HIP1R acts as a tumor suppressor in gastric cancer by promoting cancer cell apoptosis and inhibiting migration and invasion through modulating Akt.

BACKGROUND: Huntingtin-interacting protein 1-related (HIP1R) is a multi-domain gene that exerts many cellular functions including altering T cell-mediated cytotoxicity and controlling intracellular trafficking. However, its clinical significance and function in gastric cancer (GC) have not been described. METHODS: The expression levels of HIP1R were tested by the transcriptional and translational expression analysis and immunohistochemistry (IHC) in matched adjacent non-tumorous vs tumor tissue specimens. The biological function of HIP1R on apoptosis, migration, and proliferation was evaluated by flow cytometry, Transwell, Cell Counting Kit-8 (CCK-8) assays, colony formation assays, and EdU labeling assays, respectively. RESULTS: We found downregulated HIP1R in GC compared with adjacent non-tumorous tissue, and HIP1R expression associated with N classification. We further found that the expression of HIP1R could induce apoptosis and inhibit proliferation, migration, invasion of GC cells, possibly through modulating Akt. CONCLUSIONS: Our data indicate that HIP1R may act as a potential diagnostic biomarker and a tumor suppressor gene in GC, potentially representing a novel therapeutic target for future GC treatment.

Long noncoding RNA H19 participates in metformin-mediated inhibition of gastric cancer cell invasion.

Recent research suggests that the first-line oral antidiabetes drug metformin may prevent gastric cancer progression and improve prognosis. Many studies have also shown that long noncoding RNAs (lncRNAs) play important roles in many biological processes. Therefore, we aimed to explore whether lncRNAs participate in the mechanisms by which metformin affects gastric cancer cells. In the current study, we found that metformin significantly inhibited the cellular functions of gastric cancer cells through Cell Counting Kit-8 and invasion assays. We found that lncRNA H19 was greatly downregulated in gastric cancer cells treated with metformin using lncRNA microassays. Based on bioinformatics analyses of the Oncomine and The Cancer Genome Atlas databases, H19 is shown to be overexpressed in gastric cancer tissues, with increased expression of H19 relating to advanced pathological tumor stage and pathological tumor node metastasis stage, indicating that H19 may be associated with the invasive ability of gastric cancer. We knocked down H19 in AGS and SGC7901 cell lines and found that knocked-down H19 could decrease gastric cancer cell invasion and that metformin could not further decrease invasion after the knock down. Moreover, H19 depletion increased AMPK activation and decreased MMP9 expression, and metformin could not further activate AMPK or decrease MMP9 in H19 knocked-down gastric cancer cells. In summary, metformin has a profound antitumor effect on gastric cancer cells, and H19 is a key component in the process of metformin suppressing gastric cancer cell invasion.

Smoking status and subsequent gastric cancer risk in men compared with women: a meta-analysis of prospective observational studies.

BACKGROUND: Smoking is one of the well-established risk factors for gastric cancer incidence, yet whether men are more or equally susceptible to gastric cancer due to smoking compared with women is a matter of controversy. The aim of this study was to investigate and compare the effect of sex on gastric cancer risk associated with smoking. METHODS: We conducted a systemic literature search in MEDLINE, EMBASE, and the Cochrane CENTRAL databases to identify studies published from inception to December 2018. We included prospective observational studies which reported effect estimates with 95% confidence intervals (CIs) for associations of current or former smokers with the incidence of gastric cancer by sex. We calculated the ratio of relative risk (RRR) with corresponding 95% CI based on sex-specific effect estimates for current or former smokers versus non-smokers on the risk of gastric cancer. RESULTS: We included 10 prospective studies with 3,381,345 participants in our analysis. Overall, the summary RRR (male to female) for gastric cancer risk in current smokers was significantly increased compared with non-smokers (RRR: 1.30; 95% CI: 1.05-1.63; P = 0.019). Furthermore, there was no significant sex difference for the association between former smokers and gastric cancer risk (RRR: 1.20; 95% CI: 0.92-1.55; P = 0.178). However, the result of sensitivity analysis indicated the pooled result was not stable, which was altered by excluding a nested case-control study (RRR: 1.31; 95% CI: 1.10-1.57; P = 0.002). CONCLUSION: This systematic review showed a potential sex difference association between current smokers and the risk of gastric cancer. The sex differential in smokers can give important clues for the etiology of gastric cancers and should be examined in further studies.

The role of EGFR mutation as a prognostic factor in survival after diagnosis of brain metastasis in non-small cell lung cancer: a systematic review and meta-analysis.

BACKGROUND: The brain is a common site for metastasis in non-small-cell lung cancer (NSCLC). This study was designed to evaluate the relationship between the mutational of the epidermal growth factor receptor (EGFR) and overall survival (OS) in NSCLC patients with brain metastases. METHODS: Searches were performed in PubMed, EmBase, and the Cochrane Library to identify studies evaluating the association of EGFR mutation with OS in NSCLC patients through September 2017. RESULTS: 4373 NSCLC patients with brain metastases in 18 studies were involved. Mutated EGFR associated with significantly improved OS compared with wild type. Subgroup analyses suggested that this relationship persisted in studies conducted in Eastern, with retrospective design, with sample size ≥500, mean age of patients ≥65.0 years, percentage male < 50.0%, percentage of patients receiving tyrosine kinase inhibitor ≥30.0%. Finally, although significant publication bias was observed using the Egger test, the results were not changed after adjustment using the trim and fill method. CONCLUSIONS: This meta-analysis suggests that EGFR mutation is an important predictive factor linked to improved OS for NSCLC patients with brain metastases. It can serve as a useful index in the prognostic assessment of NSCLC patients with brain metastases.

Long non-coding RNA RUNX1-IT1 plays a tumour-suppressive role in colorectal cancer by inhibiting cell proliferation and migration.

Long non-coding RNAs (lncRNAs) have been demonstrated to be involved in the progression of various cancers. In this study, we aim to investigate the role of lncRNA RUNX1-IT1 in the development of colorectal cancer (CRC). The expression levels of lncRNA RUNX1-IT1 were measured using quantitative real-time Polymerase Chain Reaction(qRT-PCR). CCK8 proliferation assay, transwell assay, and flow cytometry were performed to evaluate the effect of lncRNA RUNX1-IT1 on CRC cell proliferation, migration, and apoptosis. The proliferation markers (PCNA, Ki67), apoptosis markers (cleaved-PARP, cleaved-caspase3), and MMP9 are detected by western blotting. Significant down regulation of lncRNA RUNX1-IT1 was measured in CRC tissues and three CRC cell lines (HCT116, HT29, and RKO) compared with paired nontumorous adjacent tissues (P < 0.01) or the normal colonic epithelial cell line FHC (P < 0.05), respectively. Moreover, the proliferative and migration potential of CRC cells were inhibited by overexpressing lncRNA RUNX1-IT1, which could be obviously improved by knocking down lncRNA RUNX1-IT1. The protein levels of PCNA, Ki67, and MMP9 were upregulated by overexpressing lncRNA RUNX1-IT1 and down regulated in si-RUNX1-IT1 cells. Besides, lncRNA RUNX1-IT1 could also promote the apoptosis of CRC cells. In conclusion, lncRNA RUNX1-IT1 is downregulated in CRC and plays a tumour-suppressive role due to the regulatory of cell proliferation, migration, and apoptosis. SIGNIFICANCE OF THE STUDY: We demonstrated that lncRNA RUNX1-IT1 was down regulated both in CRC tissues and cell lines. Besides, lncRNA RUNX1-IT1 could serve as a potential diagnostic biomarker and play a tumour-suppressive role owing to its good diagnostic efficacy and inhibition of CRC cell proliferation and migration.

The long noncoding RNA CTA-941F9.9 is frequently downregulated and may serve as a biomarker for carcinogenesis in colorectal cancer.

BACKGROUND: Long noncoding RNAs (lncRNAs) participate in the carcinogenesis of many different cancers. This study aimed to detect expression of lncRNA CTA-941F9.9 in colorectal cancer tissues compared with matched nontumorous adjacent tissues (NATs). Moreover, we investigated whether this molecule is able to influence carcinogenesis in colorectal cancer (CRC). METHODS: Colorectal cancer tissues and NATs from two cohorts of patients were examined. Quantitative PCR was performed to quantify levels of CTA-941F9.9 expression in these samples. The association between CTA-941F9.9 expression and clinicopathological features, including receiver operating characteristic (ROC) curves, was also analyzed to evaluate the diagnostic value of CTA-941F9.9 in CRC. Potential effects of lncRNA CTA-941F9.9 on CRC cells were assessed via autophagy, transwell assay, CCK8 assays, and flow cytometry. RESULTS: Our experimental results showed lncRNA CTA-941F9.9 to be significantly downregulated in CRC tissues in both cohorts, with areas under the ROC curve (AUC) of 0.802 and 0.876. However, no significant correlations between CTA-941F9.9 expression levels and clinicopathological characteristics or patient outcomes were observed. We also found that CTA-941F9.9 promotes autophagy in CRC cell lines but no significant function of CTA-941F9.9 in regulating cancer cell proliferation or migration. CONCLUSIONS: LncRNA CTA-941F9.9 is frequently downregulated in CRC compared with NATs and might play an important role in CRC carcinogenesis.

A nomogram for predicting bowel obstruction in preoperative colorectal cancer patients with clinical characteristics.

BACKGROUND: Bowel obstruction (BO) is a complication that commonly affects patients with colorectal cancer (CRC). BO causes severe outcomes, and its treatment leads to a dilemma for many surgeons. Moreover, the factors correlated to BO in preoperative CRC patients remain unclear. The objectives of this study were to investigate the clinical characteristics of BO to identify risk predictors and to construct a BO prediction model with preoperative CRC patients. METHODS: A large-scale, retrospective cohort, population-based study analyzed the data of 11,814 patients obtained from the Surveillance, Epidemiology, and End Results and Medicare claims-linked databases (SEER-M database). Patients aged ≥ 66 years and primarily diagnosed with CRC from 1992 to 2009 were divided into BO and non-BO groups. Cox proportional hazards regression models were used to determine predictors, and then, a nomogram was constructed by those predictors. RESULTS: A total of 11,814 patients (5293 men and 6251 women) were identified. In multivariate analysis, 14 factors were found to be associated with BO including age, race, marital status, residence location, T category, M category, primary tumor site, histologic type, histologic grade, tumor size, history of alcoholism, chemotherapy, radiotherapy, abdominal pain, and anemia. A nomogram predicting the 90- and 180-day rates of BO was built for the preoperative CRC patients with a C-index of 0.795. CONCLUSIONS: This study identified 14 BO-related factors, and a statistical model was constructed to predict the onset of BO in preoperative CRC patients. The obtained data may guide decision-making for the intervention of patients at risk for BO.

Prognostic value of gastric cancer-associated gene signatures: Evidence based on a meta-analysis using integrated bioinformatics methods.

Selecting differentially expressed genes (DEGs) based on integrated bioinformatics analyses has been used in previous studies to explore potential biomarkers in gastric cancer (GC) with microarray and RNA sequencing data. However, the genes obtained may be inaccurate because of noisy data and errors, as well as insufficient clinical sample sizes. Thus, we aimed to find robust and strong DEGs with prognostic value for GC, where the robust rank aggregation method was employed to select significant DEGs from eight Gene Expression Omnibus data sets with a total of 140 up-regulated and 206 down-regulated genes. Network data mining was then used to screen hub genes, and 11 genes were filtered using Fisher's exact test. Based on these results, we built a prognostic signature with seven genes (FBN1, MMP1, PLAU, SPARC, COL1A2, COL2A1 and ATP4A) using stepwise multivariate Cox proportional hazard regression. According to the risk score for each patient, we found that high-risk group patients had significantly worse survival results compared with those in the low-risk group (log-rank test P-value < 0.001). This seven-gene signature was then validated with an external data set. Thus, we established a signature based on seven DEGs with prognostic value for GC patients using multi-steps bioinformatics methods, which may provide novel insights and potential biomarkers for prognosis, as well as possibly serving as new therapeutic targets in clinical applications.

A panel consisting of three novel circulating lncRNAs, is it a predictive tool for gastric cancer?

Early detection is vital for prolonging 5-year survival for patients with gastric cancer (GC). Numerous studies indicate that circulating long non-coding RNAs (lncRNAs) can be used to diagnose malignant tumours. This study aimed to investigate the capacity of novel lncRNAs for diagnosing GC. A lncRNA microarray assay was used to screen differentially expressed lncRNAs between plasma of patients with GC and healthy controls. Plasma samples from 100 patients with healthy controls were used to construct a multiple-gene panel. An additional 50 pairs of GC patients with healthy controls were used to evaluate the diagnostic accuracy of the panel. Expression levels of lncRNAs were quantified through real-time polymerase chain reaction. The receiver operating characteristic curve and area under curve (AUC) were used to estimate the diagnostic capacity. We identified three lncRNAs, CTC-501O10.1, AC100830.4 and RP11-210K20.5 that were up-regulated in the plasma of GC patients with AUCs 0.724, 0.730 and 0.737, respectively (P < .01). Based on the logistic regression model, the combined AUC of the three lncRNAs was 0.764. The AUC of the panel was 0.700 in the validation cohort. These findings indicate that plasma lncRNAs can serve as potential biomarkers for detection of GC.

Long non-coding RNA-CTD-2108O9.1 represses breast cancer metastasis by influencing leukemia inhibitory factor receptor.

Breast cancer (BC) is an aggressive malignant disease in women worldwide with a high tendency to metastasize. However, important biomarkers for BC metastasis remain largely undefined. In the present study, we identified that long non-coding RNA-CTD-2108O9.1 is downregulated in BC tissues and cells and acts as a metastatic inhibitor of BC. Mechanistic investigation determined that lncRNA-CTD-2108O9.1 represses metastasis by targeting leukemia inhibitory factor receptor (LIFR), which is designated as a metastasis suppressor in BC. Our study characterizes a significant tumor suppressor active in BC metastasis repression through the known metastasis inhibitor LIFR.

Impact of timing of adjuvant chemotherapy on survival in stage III colon cancer: a population-based study.

BACKGROUND: There is no consensus regarding the optimal time to initiate adjuvant chemotherapy after surgery for stage III colon cancer, and the relevant postoperative complications that cause delays in adjuvant chemotherapy are unknown. METHODS: Eligible patients aged ≥66 years who were diagnosed with stage III colon cancer from 1992 to 2008 were identified using the linked Surveillance, Epidemiology, and End Results-Medicare database. Kaplan-Meier analysis and a Cox proportional hazards model were utilized to evaluate the impact of the timing of adjuvant chemotherapy on overall survival (OS). RESULTS: A total of 18,491 patients were included. Delayed adjuvant chemotherapy was associated with worse OS (9-12 weeks: hazard ratio [HR] = 1.222, 95% confidence interval [CI] = 1.063-1.405; 13-16 weeks: HR = 1.252, 95% CI = 1.041-1.505; ≥ 17 weeks: HR = 1.969, 95% CI = 1.663-2.331). The efficacies of adjuvant chemotherapy within 5-8 weeks and ≤4 weeks were similar (HR = 1.045, 95% CI = 0.921-1.185). Compared with the non-chemotherapy group, chemotherapy initiated at ≥21 weeks did not significantly improve OS (HR = 0.882, 95% CI = 0.763-1.018). Patients with postoperative complications, particularly cardiac arrest, ostomy infection, shock, and septicemia, had a significantly higher risk of a 4- to 11-week delay in adjuvant chemotherapy (p < 0.05). CONCLUSIONS: Adjuvant chemotherapy initiated within 8 weeks was acceptable for patients with stage III colon cancer. Delayed adjuvant chemotherapy after 8 weeks was significantly associated with worse OS. However, adjuvant chemotherapy might still be useful even with a delay of approximately 5 months. Moreover, postoperative complications were significantly associated with delayed adjuvant chemotherapy.

Effect of neoadjuvant chemotherapy in patients with gastric cancer: a PRISMA-compliant systematic review and meta-analysis.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is extensively used in the treatment of patients with gastric cancer (GC), particularly in high risk, advanced gastric cancer. Previous trials testing the efficacy of NAC have reported inconsistent results. METHODS: This study compares the combined use of NAC and surgery with surgery alone for GC by using a meta-analytic approach. We performed an electronic search of PubMed, EmBase, and the Cochrane Library to identify randomized controlled trials (RCTs) on NAC published before Oct 2015. The primary outcome of the studies was data on survival rates for patients with GC. The summary results were pooled using the random-effects model. We included 12 prospective RCTs reporting data on 1538 GC patients. RESULTS: Patients who received NAC were associated with significant improvement of OS (P = 0.001) and PFS (P < 0.001). Furthermore, NAC therapy significantly increased the incidence of 1-year survival rate (SR) (P = 0.020), 3-year SR (P = 0.011), and 4-year SR (P = 0.001). Similarly, NAC therapy was associated with a lower incidence of 1-year (P < 0.001), 2-year (P < 0.001), 3-year (P < 0.001), 4-year (P = 0.001), and 5-year recurrence rate (P = 0.002). Conversely, patients who received NAC also experienced a significantly increased risk of lymphocytopenia (P = 0.003), and hemoglobinopathy (P = 0.021). CONCLUSIONS: The findings of this study suggested that NAC is associated with significant improvement in the outcomes of survival and disease progression for GC patients while also increasing some toxicity.

Racial/ethnic disparities in the adjuvant chemotherapy of locally advanced colon cancer patients.

BACKGROUND: Most race/ethnicity-oriented investigations focus on Caucasian Americans (whites) and African Americans (blacks), leaving Asians, Hispanic white (Hispanics), and other minorities less well studied. Adjuvant chemotherapy (CT) after curative resection is critical to patients with locally advanced colon cancer (LACC). We studied the racial disparities in the adjuvant CT of LACC to aid in selecting optimal treatments for people from different races/ethnicities in this era of precision medicine. METHODS: Patients with American Joint Committee on Cancer (AJCC) stage II or III colon cancer (CC) (together termed as LACC) were included based on Surveillance, Epidemiology, and End Results cancer registry-Medicare linked databases. The log-rank test and Cox multivariate regression analysis were performed to investigate the racial/ethnic disparities in cohorts divided according to the regimen of adjuvant CT. RESULTS: In the LACC patients who did not receive adjuvant CT, Asian patients had better survival than other groups (all, P <0.05). For the fluoropyrimidine cohort, the survival of Asian patients was better than that of whites, blacks, and other minorities (all, P <0.05). For the fluoropyrimidine with oxaliplatin cohort, other minorities had superior survival to other groups (all, P <0.05). Similar findings were demonstrated for patients with AJCC stage II and III CC, and the observed better survival persisted after adjustments in the Cox models. CONCLUSIONS: Among LACC patients not receiving adjuvant CT, Asians achieved better survival than other races/ethnicities. Superior survival was also observed for Asians in the fluoropyrimidine cohort and for other minorities in the fluoropyrimidine with oxaliplatin cohort for AJCC stage III CC.