Generalizable transcriptome-based tumor malignant level evaluation and molecular subtyping towards precision oncology.

In cancer treatment, therapeutic strategies that integrate tumor-specific characteristics (i.e., precision oncology) are widely implemented to provide clinical benefits for cancer patients. Here, through in-depth integration of tumor transcriptome and patients' prognoses across cancers, we investigated dysregulated and prognosis-associated genes and catalogued such important genes in a cancer type-dependent manner. Utilizing the expression matrices of these genes, we built models to quantitatively evaluate the malignant levels of tumors across cancers, which could add value to the clinical staging system for improved prediction of patients' survival. Furthermore, we performed a transcriptome-based molecular subtyping on hepatocellular carcinoma, which revealed three subtypes with significantly diversified clinical outcomes, mutation landscapes, immune microenvironment, and dysregulated pathways. As tumor transcriptome was commonly profiled in clinical practice with low experimental complexity and cost, this work proposed easy-to-perform approaches for practical clinical promotion towards better healthcare and precision oncology of cancer patients.

Talin-1 inhibits Smurf1-mediated Stat3 degradation to modulate ß-cell proliferation and mass in mice.

Insufficient pancreatic ß-cell mass and reduced insulin expression are key events in the pathogenesis of diabetes mellitus (DM). Here we demonstrate the high expression of Talin-1 in ß-cells and that deficiency of Talin-1 reduces ß-cell proliferation, which leads to reduced ß-cell mass and insulin expression, thus causing glucose intolerance without affecting peripheral insulin sensitivity in mice. High-fat diet fed exerbates these phenotypes. Mechanistically, Talin-1 interacts with the E3 ligase smad ubiquitination regulatory factor 1 (Smurf1), which prohibits ubiquitination of the signal transducer and activator of transcription 3 (Stat3) mediated by Smurf1, and ablation of Talin-1 enhances Smurf1-mediated ubiquitination of Stat3, leading to decreased ß-cell proliferation and mass. Furthermore, haploinsufficiency of Talin-1 and Stat3 genes, but not that of either gene, in ß-cell in mice significantly impairs glucose tolerance and insulin expression, indicating that both factors indeed function in the same genetic pathway. Finally, inducible deletion Talin-1 in ß-cell causes glucose intolerance in adult mice. Collectively, our findings reveal that Talin-1 functions as a crucial regulator of ß-cell mass, and highlight its potential as a therapeutic target for DM patients.

Kindlin-2 controls angiogenesis through modulating Notch1 signaling.

Kindlin-2 is critical for development and homeostasis of key organs, including skeleton, liver, islet, etc., yet its role in modulating angiogenesis is unknown. Here, we report that sufficient KINDLIN-2 is extremely important for NOTCH-mediated physiological angiogenesis. The expression of KINDLIN-2 in HUVECs is significantly modulated by angiogenic factors such as vascular endothelial growth factor A or tumor necrosis factor α. A strong co-localization of CD31 and Kindlin-2 in tissue sections is demonstrated by immunofluorescence staining. Endothelial-cell-specific Kindlin-2 deletion embryos die on E10.5 due to hemorrhage caused by the impaired physiological angiogenesis. Experiments in vitro show that vascular endothelial growth factor A-induced multiple functions of endothelial cells, including migration, matrix proteolysis, morphogenesis and sprouting, are all strengthened by KINDLIN-2 overexpression and severely impaired in the absence of KINDLIN-2. Mechanistically, we demonstrate that KINDLIN-2 inhibits the release of Notch intracellular domain through binding to and maintaining the integrity of NOTCH1. The impaired angiogenesis and avascular retinas caused by KINDLIN-2 deficiency can be rescued by DAPT, an inhibitor of γ-secretase which releases the intracellular domain from NOTCH1. Moreover, we demonstrate that high glucose stimulated hyperactive angiogenesis by increasing KINDLIN-2 expression could be prevented by KINDLIN-2 knockdown, indicating Kindlin-2 as a potential therapeutic target in treatment of diabetic retinopathy. Our study for the first time demonstrates the significance of Kindlin-2 in determining Notch-mediated angiogenesis during development and highlights Kindlin-2 as the potential therapeutic target in angiogenic diseases, such as diabetic retinopathy.

Association between Ki67 expression and therapeutic outcome in colon cancer.

Ki67 is a commonly used proliferation marker in pathological diagnosis of tumors; however, its prognostic value in colon cancer is controversial. A total of 312 consecutive patients with stage I-III colon cancer who underwent radical surgery with or without adjuvant chemotherapy were included in the present study. Ki67 expression was assessed using immunohistochemistry and was classified according to 25% intervals. The association between Ki67 expression and clinicopathological features was analyzed. Long-term postoperative survival, including disease-free survival (DFS) and overall survival, was calculated, and its association with Ki67 was analyzed. High Ki67 expression (>50%) was associated with improved DFS in patients treated with adjuvant chemotherapy postoperatively, but not in patients who received surgery alone (P=0.138). Ki67 expression was significantly associated with histological differentiation of the tumor (P=0.01), while it was not associated with other clinicopathological factors. Multivariate analysis demonstrated that pathological T and N stage were independent prognostic factors. In conclusion, high Ki67 expression was associated with a good therapeutic outcome in patients receiving adjuvant chemotherapy in colon cancer.

Human Pluripotent Stem Cell-Mesenchymal Stem Cell-Derived Exosomes Promote Ovarian Granulosa Cell Proliferation and Attenuate Cell Apoptosis Induced by Cyclophosphamide in a POI-like Mouse Model.

Premature ovarian insufficiency (POI) is a complex disease which causes amenorrhea, hypergonadotropism and infertility in patients no more than 40 years old. Recently, several studies have reported that exosomes have the potential to protect ovarian function using a POI-like mouse model induced by chemotherapy drugs. In this study, the therapeutic potential of exosomes derived from human pluripotent stem cell-mesenchymal stem cells (hiMSC exosomes) was evaluated through a cyclophosphamide (CTX)-induced POI-like mouse model. POI-like pathological changes in mice were determined by serum sex-hormones levels and the available number of ovarian follicles. The expression levels of cellular proliferation proteins and apoptosis-related proteins in mouse ovarian granulosa cells were measured using immunofluorescence, immunohistochemistry and Western blotting. Notably, a positive effect on the preservation of ovarian function was evidenced, since the loss of follicles in the POI-like mouse ovaries was slowed. Additionally, hiMSC exosomes not only restored the levels of serum sex hormones, but also significantly promoted the proliferation of granulosa cells and inhibited cell apoptosis. The current study suggests that the administration of hiMSC exosomes in the ovaries can preserve female-mouse fertility.

To explore the regulatory role of Wnt/P53/Caspase3 signal in mouse ovarian development based on LFQ proteomics.

Early ovarian follicular development is regulated by multiple proteins and signaling pathways, including the Wnt gene. To explore the regulatory mechanism of Wnt signaling on early ovarian follicular development, ovaries from 17.5 days post coitum (17.5 dpc) mice were collected and cultured in vitro for four days in the presence of IWP2 as a Wnt activity inhibitor and KN93 as a CaMKII inhibitor. LFQ proteomics technique was then used to analyze the significant differentially abundant (P-SDA) 93 and 262 proteins in the IWP2 and KN93 groups, respectively. Of these, 63 up-regulated proteins and 30 down-regulated proteins were identified for IWP2, along with 3 significant KEGG pathways (P < 0.05). For the KN93 group, 168 up-regulated proteins and 94 down-regulated ones were P-SDA, with 9 significant KEGG pathways also noted (P < 0.05). In both IWP2 and KN93 groups, key pathways (Wnt signaling pathway, Notch signaling pathway, P53 signaling pathway, TGF-ß signaling pathway, ovarian steroid production) and metabolic regulation (energy metabolism, metal ion metabolism) were found to be related to early ovarian follicular development. Finally, western blotting demonstrated the regulatory role of Wnt/P53/Caspase3 signaling pathway in mouse ovarian development. These results contribute new knowledge to the understanding of regulatory factors of early ovarian follicular development. SIGNIFICANCE: In this study, label-free quantification (LFQ) was used in combination with liquid chromatography-mass spectrometer (LC-MS/MS) to study potential changes in the proteomic profiles of embryonic mice subjected to Wnt inhibitor IWP2 and CaMKIIinhibitor KN93. In addition, bioinformatics and comparative analyses were performed using publicly available proteomics databases to further explore the underlying mechanisms associated with early mouse ovarian growth and development.

Cyproterone Acetate Mediates IRE1α Signaling Pathway to Alleviate Pyroptosis of Ovarian Granulosa Cells Induced by Hyperandrogen.

OBJECTIVE: Hyperandrogenemia (HA) is the main pathophysiological change that takes place in polycystic ovary syndrome (PCOS). Cyproterone acetate (CYA) is a drug commonly used to reduce androgen in patients with PCOS. Long-term and continuous exposure to HA can cause ovarian granulosa cells (GCs), pyroptotic death, and follicular dysfunction in PCOS mice. The aim of this study was to investigate whether CYA could ameliorate the hyperandrogenemia-induced pyroptosis of PCOS ovarian GCs by alleviating the activation of the IRE1α signaling pathway. METHODS: Firstly, thirty PCOS patients with HA as their main clinical manifestation were selected as the study group, and thirty non-PCOS patients were selected as the control group. The GCs and follicular fluid of the patients were collected, and the expression of pyroptosis-related proteins was detected. Secondly, a PCOS mouse model induced by dehydroepiandrosterone (DHEA) was constructed, and the treatment group model was constructed with the subcutaneous injection of cyproterone acetate in PCOS mice. The expression of pyroptosis-related protein in ovarian GCs was detected to explore the alleviating effect of CYA on the pyroptosis of ovarian GCs in PCOS mice. Thirdly, KGN cells-i.e., from the human GC line-were cultured with dihydrotestosterone, CYA, and ERN1 (IRE1α gene) small interfering RNA in vitro to explore whether CYA can alleviate the activation of the IRE1α signaling pathway and ameliorate the hyperandrogenemia-induced pyroptosis of PCOS ovarian GCs. RESULTS: The expression of pyroptosis-related proteins was significantly increased in ovarian GCs of PCOS patients with HA as the main clinical manifestation, and in the PCOS mouse model induced by DHEA. After treatment with CYA, the expression of pyroptosis-related proteins in the ovarian GCs of mice was significantly lower than that in PCOS mice. In vitro experiments showed that CYA could ameliorate KGN cells' pyroptosis by alleviating the activation of the IRE1α signaling pathway. CONCLUSION: This study showed that CYA could ameliorate the activation of the IRE1α signaling pathway in mouse GCs and KGN cells, and also alleviate pyroptosis in ovarian GCs. This study provides a new mechanism and evidential support for CYA in the treatment of PCOS patients.

FAM83A antisense RNA 1 (FAM83A-AS1) silencing impairs cell proliferation and induces autophagy via MET-AMPKɑ signaling in lung adenocarcinoma.

Studies demonstrate that long non-coding RNAs (lncRNAs) play vital roles in cancer progression. However, the expression pattern and molecular mechanisms of lncRNA FAM83A-AS1 in lung cancer remain largely unclear. Here, we analyzed FAM83A-AS1 expression in lung cancer tissues from three RNA-sequencing (RNA-Seq) datasets and validated these results using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) in an independent set of lung adenocarcinoma. Cell proliferation, migration, invasion, and autophagy were analyzed after knockdown FAM83A-AS1 with siRNAs. The underlying molecular mechanisms of FAM83A-AS1 were performed by Western blot, qRT-PCR, and RNA-seq analysis. We found that FAM83A-AS1 was up-regulated in lung cancer and elevated expression was associated with poor patient survival. These results were confirmed using RT-PCR in an independent set of lung cancer. Functional study indicated that FAM83A-AS1 knockdown reduced cell proliferation, migration, invasion, and colony formation in cancer cells. FAM83A-AS1 silencing induced autophagy and cell cycle arrest at G2. Mechanistically, serval oncogenic proteins such as EGFR, MET, PI3K, and K-RAS were decreased upon FAM83A-AS1 silencing, while phosphor AMPKα and ULK1 were increased. Based on the above results, we believe that FAM83A-AS1 may have potential as a diagnosis/prognosis marker and its oncogenic role and autophagy regulation may be through MET-AMPKα signaling, which could lead to potential targeting for lung cancer therapy.

Purine Synthesis Inhibitor L-Alanosine Impairs Mitochondrial Function and Stemness of Brain Tumor Initiating Cells.

Glioblastoma (GBM) is a lethal brain cancer exhibiting high levels of drug resistance, a feature partially imparted by tumor cell stemness. Recent work shows that homozygous MTAP deletion, a genetic alteration occurring in about half of all GBMs, promotes stemness in GBM cells. Exploiting MTAP loss-conferred deficiency in purine salvage, we demonstrate that purine blockade via treatment with L-Alanosine (ALA), an inhibitor of de novo purine synthesis, attenuates stemness of MTAP-deficient GBM cells. This ALA-induced reduction in stemness is mediated in part by compromised mitochondrial function, highlighted by ALA-induced elimination of mitochondrial spare respiratory capacity. Notably, these effects of ALA are apparent even when the treatment was transient and with a low dose. Finally, in agreement with diminished stemness and compromised mitochondrial function, we show that ALA sensitizes GBM cells to temozolomide (TMZ) in vitro and in an orthotopic GBM model. Collectively, these results identify purine supply as an essential component in maintaining mitochondrial function in GBM cells and highlight a critical role of mitochondrial function in sustaining GBM stemness. We propose that purine synthesis inhibition can be beneficial in combination with the standard of care for MTAP-deficient GBMs, and that it may be feasible to achieve this benefit without inflicting major toxicity.

Surgery may not benefit patients with locally advanced rectal cancer who achieved clinical complete response following neoadjuvant chemoradiotherapy.

PURPOSE: We compared the long-term outcome of the watch and wait (WW) strategy and surgery in patients with locally advanced rectal cancer. PATIENTS AND METHODS: This prospective cohort study included 84 patients who achieved clinical complete response (cCR) after neoadjuvant chemoradiotherapy (NCRT). They were divided into the WW group (n = 58) and surgery group (SG, n = 26). Patients in the SG underwent total mesorectal excision. The study site was the Peking University Cancer Hospital. RESULTS: Eighty-four patients were included (58 and 26 in the WW group and SG, respectively). A total of 76·9% of the patients in the SG achieved pathological complete response (pCR) and 23·1% of the patients had a residual tumor. The total recurrence and metastasis rate was 15·4% (4/26) in the SG and 18·9% (11/58) in the WW group. There was no significant difference in the recurrence and metastasis rate between the two groups. In the WW group, 9 cases developed tumor regrowth during follow-up and underwent salvage surgery. The overall survival rate of the WW group (96·6% vs 92·3%) was not significantly different from that of the SG (P > 0·05). The WW patients also retained their anal sphincter function and avoided surgery-related complications. CONCLUSION: The WW strategy is a feasible treatment option in patients with cCR after NCRT. Surgery may not bring benefits to these cCR patients.

Circulating Tumor Cells (CTCs): A Unique Model of Cancer Metastases and Non-invasive Biomarkers of Therapeutic Response.

Late-stage cancer metastasis remains incurable in the clinic and is the major cause death in patients. Circulating tumor cells (CTCs) are thought to be metastatic precursors shed from the primary tumor or metastatic deposits and circulate in the blood. The molecular network regulating CTC survival, extravasation, and colonization in distant metastatic sites is poorly defined, largely due to challenges in isolating rare CTCs. Recent advances in CTC isolation and ex vivo culture techniques facilitates single-cell omics and the development of related animal models to study CTC-mediated metastatic progression. With these powerful tools, CTCs can potentially be used as non-invasive biomarkers predicting therapeutic response. These studies may open a new avenue for CTC-specific drug discoveries. In this short review, we aim to summarize recent progress in the characterization of CTCs and their clinical relevance in various cancers, setting the stage for realizing personalized therapies against metastases.

Epigenetic Regulation of Fanconi Anemia Genes Implicates PRMT5 Blockage as a Strategy for Tumor Chemosensitization.

Strengthened DNA repair pathways in tumor cells contribute to the development of resistance to DNA-damaging agents. Consequently, targeting proteins in these pathways is a promising strategy for tumor chemosensitization. Here, we show that the expression of a subset of Fanconi anemia (FA) genes is attenuated in glioblastoma tumor cells deficient in methylthioadenosine phosphorylase (MTAP), a common genetic alteration in a variety of cancers. Subsequent experiments in cell line models of different cancer types illustrate that this reduced transcription of FA genes can be recapitulated by blockage of Protein Arginine Methyltransferase 5 (PRMT5), a promising therapeutically targetable epigenetic regulator whose enzymatic activity is compromised in MTAP-deficient cells. Further analyses provide evidence to support that PRMT5 can function as an epigenetic regulator that contributes to the increased expression of FA genes in cancer cells. Most notably and consistent with the essential roles of FA proteins in resolving DNA damage elicited by interstrand crosslinking (ICL) agents, PRMT5 blockage, as well as MTAP loss, sensitizes tumor cells to ICL agents both in vitro and in xenografts. Collectively, these findings reveal a novel epigenetic mechanism underlying the upregulated expression of FA genes in cancer cells and suggest that therapeutically targeting PRMT5 can have an additional benefit of chemosensitizing tumor cells to ICL agents. IMPLICATIONS: PRMT5 positively regulates the expression of FA genes. Inhibition of PRMT5 attenuates FA-dependent DNA repair pathway and sensitizes tumor cells to ICL agents.

Low levels of BRCA1 protein expression predict a worse prognosis in stage I-II colon cancer.

BACKGROUND: BRCA1 and BRCA2 have been well studied for their roles in tumorigeneis, plus cancer diagnosis and treatment, but their prognostic value in colon cancer, especially for early-stage cancer, has not been fully illuminated. This study examined the expression levels of BRCA1 and BRCA2 proteins in sporadic colon cancer cases and investigated their value in prognosis. METHODS: The expression levels of BRCA1 and BRCA2 in 275 colon cancer patients who underwent radical surgeries were assayed by immunohistochemical staining in dissected tumor samples. Also, its correlation with clinicopathological characteristics, disease-free survival, and overall survival was investigated. RESULTS: Tumors with low expression levels of BRCA1, BRCA2, and both were 19.6%, 17.8%, and 6.5%, respectively. The levels of BRCA1/2 expression were not associated with clinicopathological parameters (gender, age, histological differentiation, and tumor node metastasis stage). Patients with low-levels of BRCA1 protein in their tumors demonstrated a lower chance of 5-year disease-free survival (55.6% vs. 69.7%, P=0.046), which was more obvious in the patients with stage I-II tumors without chemotherapy (52.6% vs. 82.6%, P=0.006). Neither BRCA1 nor BRCA2 affected overall survival in this cohort. Multivariate analysis revealed that pathologic stage and the level of BRCA1 protein were independent factors of long-term disease-free survival. CONCLUSION: This study highlights BRCA1 as an independent prognosticator of early-stage colon cancer.

Targeting Mutant PPM1D Sensitizes Diffuse Intrinsic Pontine Glioma Cells to the PARP Inhibitor Olaparib.

Diffuse intrinsic pontine glioma (DIPG) is an invariably fatal brain tumor occurring predominantly in children. Up to 90% of pediatric DIPGs harbor a somatic heterozygous mutation resulting in the replacement of lysine 27 with methionine (K27M) in genes encoding histone H3.3 (H3F3A, 65%) or H3.1 (HIST1H3B, 25%). Several studies have also identified recurrent truncating mutations in the gene encoding protein phosphatase 1D, PPM1D, in 9%-23% of DIPGs. Here, we sought to investigate the therapeutic potential of targeting PPM1D, alone or in combination with inhibitors targeting specific components of DNA damage response pathways in patient-derived DIPG cell lines. We found that GSK2830371, an allosteric PPM1D inhibitor, suppressed the proliferation of PPM1D-mutant, but not PPM1D wild-type DIPG cells. We further observed that PPM1D inhibition sensitized PPM1D-mutant DIPG cells to PARP inhibitor (PARPi) treatment. Mechanistically, combined PPM1D and PARP inhibition show synergistic effects on suppressing a p53-dependent RAD51 expression and the formation of RAD51 nuclear foci, possibly leading to impaired homologous recombination (HR)-mediated DNA repair in PPM1D-mutant DIPG cells. Collectively, our findings reveal the potential role of the PPM1D-p53 signaling axis in the regulation of HR-mediated DNA repair and provide preclinical evidence demonstrating that combined inhibition of PPM1D and PARP1/2 may be a promising therapeutic combination for targeting PPM1D-mutant DIPG tumors. IMPLICATIONS: The findings support the use of PARPi in combination with PPM1D inhibition against PPM1D-mutant DIPGs.

A PRMT5-RNF168-SMURF2 Axis Controls H2AX Proteostasis.

H2AX safeguards genomic stability in a dose-dependent manner; however, mechanisms governing its proteostasis are poorly understood. Here, we identify a PRMT5-RNF168-SMURF2 cascade that regulates H2AX proteostasis. We show that PRMT5 sustains the expression of RNF168, an E3 ubiquitin ligase essential for DNA damage response (DDR). Suppression of PRMT5 occurs in methylthioadenosine phosphorylase (MTAP)-deficient glioblastoma cells and attenuates the expression of RNF168, leading to destabilization of H2AX by E3 ubiquitin ligase SMURF2. RNF168 and SMURF2 serve as a stabilizer and destabilizer of H2AX, respectively, via their dynamic interactions with H2AX. In supporting an important role of this signaling cascade in regulating H2AX, MTAP-deficient glioblastoma cells display higher levels of DNA damage spontaneously or in response to genotoxic agents. These findings reveal a regulatory mechanism of H2AX proteostasis and define a signaling cascade that is essential to DDR and that is disrupted by the loss of a metabolic enzyme in tumor cells.

Value of intra-operative Doppler sonographic measurements in predicting post-operative anastomotic leakage in rectal cancer: a prospective pilot study.

BACKGROUND: Anastomotic leakage is a serious surgical complication in rectal cancer; however, effective evaluation methods for predicting anastomotic leakage individual risk in patients are not currently available. This study aimed to develop a method to evaluate the risk of leakage during surgery. METHODS: The 163 patients with rectal cancer, who had undergone anterior resection and low-ligation procedures for Doppler sonographic hemodynamic measurement from April 2011 to January 2015 in Peking University Cancer Hospital, were prospectively recruited. A predictive model was constructed based on the associations between anastomotic leakage and alterations in the anastomotic blood supply in the patients, using both univariate and multivariate statistical analyses, as well as diagnostic methodology evaluation, including Chi-square test, logistic regression model, and receiver operating characteristic curve. RESULTS: The overall anastomotic leakage incidence was 9.2% (15/163). Doppler hemodynamic parameters whose reduction was significantly associated with anastomotic leakage were peak systolic velocity, pulsatility index, and resistance index. The areas under the receiver operating characteristic curve of residual rates of peak systolic velocity, pulsatility index, and resistance index in predicting anastomotic leakage were 0.703 (95% confidence interval [CI]: 0.552-0.854), 0.729 (95% CI: 0.579-0.879), and 0.689 (95% CI: 0.522-0.856), respectively. The predictive model revealed that the patients with severely reduced blood-flow signal exhibited a significantly higher incidence rate of anastomotic leakage than those with sufficient blood supply (19.6% vs. 3.7%, P = 0.003), particularly the patients with low rectal cancer (25.9% vs. 3.9%, P = 0.007) and those receiving neoadjuvant chemoradiotherapy (32.1% vs. 3.7%, P = 0.001), independent of prophylactic ileostoma. Multivariate analysis revealed that insufficient blood supply of the anastomotic bowel was an independent risk factor for anastomotic leakage (odds ratio: 10.37, 95% CI: 2.703-42.735, P = 0.001). CONCLUSION: Based on this explorative study, Doppler sonographic hemodynamic measurement of the anastomotic bowel presented potential value in predicting anastomotic leakage.

[Long-term prognostic analysis on complete/near-complete clinical remission for mid-low rectal cancer after neoadjuvant chemoradiotherapy].

OBJECTIVE: To investigate the long-term outcome of organ preservation with local excision or "watch and wait" strategy for mid-low rectal cancer patients evaluated as clinical complete remission (cCR) or near-cCR following neoadjuvant chemoradiotherapy (NCRT). METHODS: Clinical data of 62 mid-low rectal cancer patients evaluated as cCR/near-cCR after NCRT undergoing organ preservation surgery with local excision or receiving "watch and wait" strategy at Department of Gastrointestinal Surgery, Peking University Cancer Hospital and Institute from March 2011 to August 2017 were retrospectively analyzed. According to the approximate 1:2 pairing, 123 patients who underwent radical resection with complete pathological remission(ypCR) after neoadjuvant chemotherapy during the same period were selected for prognosis comparison. The primary endpoint of the study was 3-year non-regrowth disease-free survival (NR-DFS) and tumor specific survival (CSS). Survival analysis was performed using the Kaplan-Meier curve (Log-rank method). The secondary endpoint of the study was 3-year organ preservation and sphincter preservation. RESULTS: The retrospective study included 38 male and 24 female patients. The median age was 60 (31-79) years and the median distance from tumor to anal verge was 4(1-8) cm. The ratio of cCR and near-cCR was 79.0%(49/62) and 21.0%(13/62) respectively. Local regrowth rate was 24.2%(15/62). Of 15 with tumor regrowth, 9 patients received salvage radical rectal resection and no local recurrence was found during follow-up; 4 patients received salvage local excision among whom one patient had a local recurrence occurred patient; 2 patients refused further surgery. The overall metastasis rate was 8.1%(5/62), including resectable metastasis(4.8%,3/62) and unresectable metastasis (3.2%,2/62). The valid 3-year organ preservation rate and sphincter preservation rate were 85.5%(53/62) and 95.2%(59/62) respectively. The median follow-up was 36.2(8.6-89.0) months. The 3-year NR-DFS of patients with cCR and near-cCR was 88.6% and 83.1% respectively, which was not significantly different to that of patients with ypCR (94.7%, P=0.217). The 3-year CSS of patients with cCR and near-cCR was both 100%, which was not significantly different to that of patients with ypCR(93.4%, P=0.186). CONCLUSIONS: Mid-low rectal cancer patients with cCR or near-cCR after NCRT undergoing organ preservation with local excision or receiving "watch and wait" strategy have good long-term prognosis with low rates of local tumor regrowth and distant metastasis, which is similar to those with ypCR after radical surgery. This treatment mode may be used as an option for organ preservation in mid-low rectal cancer patients with good tumor remission after NCRT.

Lysine-specific demethylase 2A expression is associated with cell growth and cyclin D1 expression in colorectal adenocarcinoma.

OBJECTIVE: Lysine-specific demethylase 2A (KDM2A), a specific H3K36me1/2 demethylase, has been reported to be closely associated with several types of cancer. In this study, we aimed to investigate the expression and function of KDM2A in colorectal adenocarcinoma. METHODS: A total of 215 colorectal adenocarcinoma specimens were collected, and then subjected to immunohistochemistry assay to evaluate the expression levels of KDM2A, cyclin D1 and other proteins in colorectal adenocarcinoma tissues. Real-time polymerase chain reaction, Western blot, and other molecular biology methods were used to explore the role of KDM2A in colorectal adenocarcinoma cells. RESULTS: In this study, we report that the expression level of KDM2A is high in colorectal adenocarcinoma tissues, and this high expression promotes the proliferation and colony formation of colorectal adenocarcinoma cells, as demonstrated by KDM2A knockdown experiments. In addition, the expression of KDM2A is closely associated with cyclin D1 expression in colorectal adenocarcinoma tissues and cell lines. CONCLUSIONS: Our study reveals a novel role for high-expressed KDM2A in colorectal adenocarcinoma cell growth, and that the expression of KDM2A is associated with that of cyclin D1 in colorectal adenocarcinoma.

Overexpression of LAMC2 predicts poor prognosis in colorectal cancer patients and promotes cancer cell proliferation, migration, and invasion.

Laminin γ2 (LAMC2) has been reported to be involved in the development and progression of a variety of tumors. However, its function in human colorectal cancer is unclear. Our study aimed to investigate the role of laminin γ2 in colorectal cancer. We first performed the multiple Kaplan-Meier survival analysis of laminin γ2 in a cohort of Gene Expression Omnibus datasets and evaluated its relationship with clinical outcomes of colorectal cancer patients. Then, we established stable colorectal cancer cell lines with laminin γ2 overexpression and examined the functional assays in vitro. Finally the expression pattern of laminin γ2 in colorectal cancer clinical samples was analyzed by immunohistochemistry and quantitative real-time polymerase chain reaction. We found that laminin γ2 was significantly correlated with poor clinical outcomes such as disease-specific, recurrence-free, disease-free, and overall survival in colorectal cancer. Moreover, stably overexpressing laminin γ2 promoted proliferation, migration, and invasion of colorectal cancer cells. In addition, overexpressed laminin γ2 was identified in tumor tissues compared with paired adjacent normal tissues and was related to tumor-node-metastasis stage (p = 0.001) and lymph node metastasis (p < 0.001). In summary, our results strongly suggest that laminin γ2 may be a potential prognostic biomarker and therapeutic target in colorectal cancer.

5-Fluorouracil targets histone acetyltransferases p300/CBP in the treatment of colorectal cancer.

Although 5-fluorouracil (5-FU) is known to interfere with the synthesis of ribonucleic acid and deoxyribonucleic acid, the mechanism underlying its therapeutic efficacy in colorectal cancer (CRC) has not been fully elucidated. We aimed to investigate the influence of 5-FU on histone acetylation, a well-established anti-cancer target, to reveal novel pharmacological effects of 5-FU and their significance for CRC therapy. Results demonstrated that 5-FU induces global histone de-acetylation in multiple CRC cell lines. We identified that 5-FU reduces the binding ability of histone acetyltransferases p300 and CBP to chromatin, and induces their degradation through lysosome. Further work revealed that the degradation of p300/CBP induced by 5-FU was dependent on chaperone-mediated autophagy, mediated by heat-shock cognate protein 70 kDa (hsc70) and lysosomal-associated membrane protein 2A (LAMP2A). Moreover, the degradation of p300/CBP is relevant to cellular resistance to 5-FU, since blocking the degradation enhances 5-FU's cytotoxicity in CRC cells. From clinical data, we demonstrated that low expression of p300/CBP in CRC tissue was closely associated with poor clinical response to 5-FU based-chemotherapy, based on the analysis of 262 colorectal samples from the patients receiving 5-FU treatment: compared to cases with high expression of p300/CBP, those with low expression had lower long-term disease-free survival rate and increased early-progression. These results elucidate a novel pharmacological effect of 5-FU involving global histone de-acetylation by promoting the degradation of p300/CBP, and highlights p300 and CBP as promising predictors of chemo-sensitivity to 5-FU treatment.