[Analysis of prognosis and related factors in oldest-old patients with left-side or right-side colon cancer after hemicolectomy].

Objective: This study aimed to explore the difference of prognosis in oldest-old colon cancer patients between the left-side and right-side hemicolectomy. Methods: A total of 238 oldest-old (≥75 years old) colon cancer patients who received surgical treatment in Gastrointestinal Surgery Department of Beijing Hospital from December 2010 to December 2020 were retrospectively collected. They were divided into right-side hemicolectomy (RCC) group (130 cases) and left-side hemicolectomy (LCC) group (108 cases) by surgical methods. The difference in postoperative short-term complications and long-term prognosis was compared between the two groups, and the related factors of postoperative death was analyzed using multivariate Cox regression model. Results: The age of 238 oldest-old patients with colon cancer ranged from 75 to 93 years old (80.5±3.7). There were 128 males and 110 females. The ages of patients in the LCC group and RCC group were (80.4±3.7) and (80.6±3.7) years old (P=0.699), respectively. There was no significant difference in gender, body mass index (BMI) and co-existing chronic diseases between two groups (P>0.05). The proportion of the duration of surgery exceeding 170 min in the LCC group was significantly higher than that in the RCC group (56.5% vs 43.1%, P=0.039). The incidence of postoperative short-term complications in RCC group was slightly higher than LCC group (P>0.05), and there was no significant difference in overall survival (OS), tumor-specific survival (CSS) and disease-free survival (DFS) between two groups. However, the two groups had different prognostic risk factors, pathological Ⅳ stage (HR=28.970,95%CI:1.768-474.813,P=0.018), intraoperative bleeding (HR=2.297,95%CI:1.351-3.907,P=0.002) and cancer nodules (HR=2.044,95%CI:1.047-3.989,P=0.036) were independent prognostic risk factors in LCC group. Underweight (HR=0.428,95%CI:0.192-0.955,P=0.038), overweight(HR=0.316,95%CI:0.125-0.800,P=0.015),obesity (HR=0.211,95%CI:0.067-0.658,P=0.007), lymph node metastasis (HR=2.682,95%CI:1.497-4.807,P=0.001), tumor nodule (HR=2.507,95%CI:1.301-4.831,P=0.027) and postoperative length of stay of 9 days (HR=1.829,95%CI:1.070-3.128,P=0.006) were independent risk factors for poor prognosis in RCC group. Conclusions: The duration of surgery of oldest-old colon cancer patients in the LCC group was longer than that in the RCC group. However, there was no significant difference in the incidence of postoperative complications between the two groups. High pathological stage, more intraoperative bleeding and cancer nodules were independent prognostic risk factors in the LCC group. Abnormal BMI, lymph node metastasis, cancer nodules and postoperative length of stay were independent risk factors for poor prognosis in the RCC group.

[Risk factors for low anterior resection syndrome].

Objective: While low anterior resection avoided a permanent stoma, it might also cause bowel dysfunction which can significantly impact patients' quality of life. The objective of this study was to identify the incidence and risk factors for the development of bowel dysfunction following rectal surgery. Methods: Patients undergoing anterior resection for rectal neoplasm between January 2010 and December 2015 were identified from a rectal cancer database at the Department of Gastrointestinal Surgery, Beijing Hospital. All patients were asked to fill in a low anterior resection syndrome (LARS) questionnaire. Clinical factors were compared between patients with major LARS and those with minor or no LARS using conditional logistic regression. Results: There was 254 patients enrolled in the study. One hundred and eleven (44.1%) had major LARS symptoms. Neoadjuvant radiotherapy (OR=2.814, 95%CI: 1.097-5.561, P<0.001), low tumor location (OR=3.568, 95%CI: 1.159-6.546, P<0.001) and anastomotic leakage (OR=6.574, 95%CI: 1.689-15.367, P<0.001) were independent risk factors for development of major LARS symptoms. Conclusions: For patients with high risk of low anterior resection syndrome, the potential for long-term poor functional results should be discussed with patients and form a part of the decision-making in individual treatment plans. Sphincter-preserving surgery should be performed in highly selected patients to avoid major bowel dysfunction.

[Assessment of predictive factors for survival in patients with locally advanced rectal cancer after neoadjuvant chemoradiotherapy].

Objective: To evaluate the clinical predictive factors for survival prognosis in patients with locally advanced rectal cancer after neoadjuvant chemoradiotheraphy. Methods: The study included 87 patients with middle and lower locally advanced rectal cancer, who underwent neoadjuvant chemoradiotheraphy followed by radical surgery between April 2007 and May 2015. The clinical factors associated with 3-year disease-free survival (DFS) and overall survival (OS) were analyzed.Kaplan-Meier analysis of disease-free survival and overall survival was performed for all patients. Results: The 3-year DFS was significantly improved in patients with negative lymph node(95.2% vs 69.5%, χ(2)=8.642, P=0.003). The 3-year OS was better in the patients with lower serum level of pre- chemoradiotheraphy carcino-embryonic antigen (CEA)(90.9% vs 66.7%, χ(2)=8.820, P=0.003). Cox regression multivariate analysis revealed that serum level of pre-chemoradiotheraphy CEA was an independent predictive factor for 3-year OS(P=0.035). Conclusion: Serum level of pre- chemoradiotheraphy CEA is an independent risk factor for 3-year OS.

[Analysis of clinical predictive factors of pathologic complete response after neoadjuvant chemoradiotherapy in rectal cancer].

OBJECTIVE: To evaluate the clinical predictive factors associated with pathologic complete response (pCR) after neoadjuvant chemoradiotherapy in rectal cancer. METHODS: A retrospective analysis was performed on clinical data of 87 patients with rectal cancer, who underwent neoadjuvant chemoradiotherapy followed by radical surgery from April 2007 to May 2015. All patients received pelvic intensity-modulated radiotherapy (50 Gy/25 fractions) with concurrent fluorouracil- based chemotherapy and then underwent radical surgery 4-8 weeks later. The clinical factors associated with pCR or non-pCR were analyzed by Logistic regression. RESULTS: Eighty-three patients had completed treatment, of which 15 patients (18.1%) achieved pCR after neoadjuvant chemoradiotherapy. Univariate analysis showed non-diabetes(P=0.033), pre-chemoradiotherapy plasma glucose(≤6.1 mmol/L)(P=0.033), pre-chemoradiotherapy CEA(≤5 µg/L)(P=0.026), pre- chemoradiotherapy plasma lymphocytes count(≤1.5×10(9)/L)(P=0.042), pre- chemoradiotherapy plasma platelet(≤240×10(12))(P=0.043), tumor pathological type(adenocarcinoma)(P=0.036)were significantly correlated with pCR after neoadjuvant chemoradiotherapy in rectal cancer. Logistic regression revealed that non-diabetes, pre-chemoradiotherapy plasma glucose, pre-chemoradiotherapy CEA(≤5 µg/L), pre-chemoradiotherapy plasma lymphocytes count(≤1.5×10(9)/L), tumor pathological type(adenocarcinoma) were independent predictive factors of pCR after neoadjuvant chemoradiotherapy in rectal cancer. CONCLUSION: Patients with non-diabetes, normal plasma glucose, normal CEA, lower plasma lymphocytes count and adenocarcinoma were associated with pCR after neoadjuvant chemoradiotherapy for rectal cancer.

Intravesical treatment of advanced urothelial bladder cancers with oncolytic HSV-1 co-regulated by differentially expressed microRNAs.

Urothelial bladder cancer is the most common malignancy of the urinary tract. Although most cases are initially diagnosed as non-muscle-invasive, more than 80% of patients will develop recurrent or metastatic tumors. No effective therapy exists currently for late-stage metastatic tumors. By intravesical application, local administration of oncolytic Herpes Simplex virus (oHSV-1) can provide a promising new therapy for this disease. However, its inherent neurotoxicity has been a perceived limitation for such application. In this study, we present a novel microRNA-regulatory approach to reduce HSV-1-induced neurotoxicity by suppressing viral replication in neurons while maintaining oncolytic selectivity toward urothelial tumors. Specifically, we designed a recombinant virus that utilizes differentially expressed endogenous microR143 (non-cancerous, ubiquitous) and microR124 (neural-specific) to regulate expression of ICP-4, a gene essential for HSV-1 replication. We found that expression of ICP-4 must be controlled by a combination of both miR143 and miR124 to achieve the most effective attenuation in HSV-1-induced toxicity while retaining maximal oncolytic capacity. These results suggest that interaction between miR143 and miR124 may be required to successfully regulate HSV-1 replication. Our resent study is the first proof-in-principle that miRNA combination can be exploited to fine-tune the replication of HSV-1 to treat human cancers.

An HSV-1 amplicon system for prostate-specific expression of ICP4 to complement oncolytic viral replication for in vitro and in vivo treatment of prostate cancer cells.

The aim of the present study was to determine whether a prostate-specific amplicon, containing a probasin-derived promoter (ARR(2)PB) upstream of an essential Herpes simplex virus-1 (HSV-1) viral gene, infected-cell polypeptide 4 (ICP4), could complement an HSV-1 helper virus with this gene deleted (ICP4-) and cause lytic replication specifically in prostate cancer cells. Two amplicon constructs, CMV-ICP4 and ARR(2)PB-ICP4, were packaged by a replication-deficient ICP4- helper virus. The amplicon viruses could complement ICP4- helper viruses to efficiently replicate and cause cell lysis in prostate cancer cells. Intratumoral injection of LNCaP human prostate cancer xenografts with either amplicon/helper virus resulted in >75% reduction in tumor volume and serum prostate specific antigen (PSA). Histological and Q-PCR (quantitative PCR) analyses indicated that the toxicity in nontumor tissues was much lower with ARR(2)PB-ICP4 than with CMV-ICP4 amplicon/helper virus. In conclusion, a replication-deficient HSV-1 virus could be complemented by an amplicon virus to restore its oncolytic activity in a tissue-specific and low toxicity fashion, illustrating that this approach could be a potentially useful strategy for developing an oncolytic viral therapy for prostate cancer.

Targeting and killing of prostate cancer cells using lentiviral constructs containing a sequence recognized by translation factor eIF4E and a prostate-specific promoter.

To develop a gene therapy that would selectively kill prostate cancer cells while sparing normal cells, we have constructed lentiviral vectors that contain a therapeutic gene with a short DNA sequence in the 5'-untranslated region (UTR) that is recognized by the translation initiation factor, eIF4E, which is often overexpressed in malignant cells. Infection of cancer (LNCaP, PC-3M, DU145, and MCF-7 cells) and noncancer cell lines (BPH-1, 267-B1, Plat-E, and Huvec-c cells) with lentivirus having a CMV-promoter and EGFP reporter resulted in high levels of EGFP expression in all cells, whereas, inclusion of the eIF4E UTR recognition sequence restricted high expression to cancer cells and Plat-E cells, which also express substantial levels of eIF4E. Infection of the cells with lentiviral vectors having this UTR in front of the HSV thymidine kinase suicide gene resulted in differential sensitivity to the killing effects of ganciclovir, with at least 100-fold more drug required to kill noncancer cells than cancer cells. Furthermore, in experiments where the CMV promoter was replaced by the prostate-specific ARR(2)PB promoter, the killing effects of ganciclovir were restricted to prostate cancer cells and not seen in nonprostate cancer cells. Our results indicate that combined translational regulation, by incorporation of an eIF4E-UTR recognition sequence into a therapeutic gene, together with transcriptional regulation with a prostate-specific promoter, may provide a means to selectively destroy prostate cancer cells while sparing normal prostate cells.

Herpes simplex virus type-1 infection upregulates cellular promoters and telomerase activity in both tumor and nontumor human cells.

Targeted gene expression through viral vectors has been a promising approach for gene therapy. However, the effects of viral gene products expressed from virus vectors on the expression of the host gene are not well known. In the present study, we examined the activities of cellular promoters, including the promoter for genes of human telomerase reverse transcriptase (hTERT), tyrosinase and probasin, in both tumor and normal cells after infection with herpes simplex virus type 1 (HSV-1) vectors. Our results showed that infection with replication-defective HSV-1 vectors significantly upregulated the activity of all three cellular promoters in a nonsequence specific fashion in all cell types tested. Furthermore, viral infection upregulated activities of the hTERT promoter and endogenous telomerase in nontumoral cells. Additional experiments suggested that the viral immediate-early gene product, infected cell protein 0, might be responsible for the deregulation of cellular promoter activity and activation of telomerase. Our study alerts to the potential risk of oncogenesis through deregulation of host gene expression, such as the telomerase by viral vectors in normal cells.

Bax expressed from a herpes viral vector enhances the efficacy of N,N'-bis(2-hydroxyethyl)-N-nitrosourea treatment in a rat glioma model.

N,N'-bis(2-hydroxyethyl)-N-nitrosourea (BCNU) is a commonly used agent for treatment of malignant gliomas. The mechanisms of cell death and the role of Bcl-2 and Bax in a BCNU-treated rat glioma cell line were investigated. Our results indicate that apoptosis occurs only at a high concentration of BCNU with elevated levels of Bax and a reversed ratio of Bax/Bcl-2. Overexpression of Bax delivered by a herpes simplex viral vector in combination with BCNU chemotherapy enhanced the efficacy of BCNU in a rat glioma model. These findings suggest that conventional treatment with BCNU may be combined with gene therapy that delivers a bax gene into the glioma cells to achieve a high level of Bax, facilitating BCNU-induced cytotoxicity.

A bcl-2 expressing viral vector protects cortical neurons from excitotoxicity even when administered several hours after the toxic insult.

The product of the bcl-2 oncogene has been shown to play an important role in apoptosis and programmed cell death. In this study, a herpes simplex virus type-1 vector was constructed to carry the human bcl-2 gene. The possible role of bcl-2 in protecting neurons from excitoxicity was investigated by using the viral vector to deliver the gene into neuronal cultures before or after the cells were exposed to glutamate under conditions in which 50-80% of neurons died. Infection with the bcl-2 expressing vector 24 h prior to glutamate treatment effectively prevented the cell death that normally follows this treatment. Moreover, infection with the vector as late as 8 h after the glutamate insult still resulted in substantial neuroprotective effects. These results have potential implications for new therapies in stroke or ischemic neuropathies.

Toxicity studies in thymidine kinase-deficient herpes simplex virus therapy for malignant astrocytoma.

Previous studies have shown that genetically engineered thymidine kinase (tk)-defective herpes simplex virus type 1 (HSV-1) can effectively and selectively destroy gliomas in animal models. The consequences of viral infection and tumor regression must be characterized before this therapy can be applied in human trials. To study the potential for long-term toxicity, immunocompetent rats harboring 9L gliosarcomas were injected intratumorally with a tk-defective HSV-1, KOS-SB, at titers that previously have been demonstrated to cause tumor regression. In animals surviving 3 months or longer following viral treatment, there was no evidence of persistent infection or inflammation in peritumoral brain tissue or in remote systemic organs studied with routine histological and immunocytochemical analyses. Polymerase chain reaction using primers specific for HSV-1 detected HSV-1 DNA in peritumoral tissue only in animals sacrificed within 3 months of viral injection. There was no evidence of HSV-1 DNA in systemic tissues at any time after treatment. We conclude that stereotactic intratumoral injection of tk-deficient HSV can be attempted for the treatment of brain tumors without risk of systemic infection or significant toxicity to normal brain or remote proliferating tissues.

Selective destruction of gliomas in immunocompetent rats by thymidine kinase-defective herpes simplex virus type 1.

BACKGROUND: Thymidine kinase-deficient herpes simplex virus type 1 [tk(-) HSV-1] replicates well in dividing cells but not in nondividing cells such as neurons, suggesting a potential use in the treatment of brain tumors. PURPOSE: We attempted to examine the efficacy of using tk(-) HSV-1 for treating brain tumors in immunocompetent animals. METHODS: 9L glioma cells were cultured and subsequently implanted intracerebrally in immunocompetent, adult male Long-Evans rats. A thymidine kinase-defective HSV-1 virus, KOS-SB, was used to infect 9L cells in culture, and the viability of the infected cells was compared with that of mock-infected (i.e., uninfected) cells. We also injected the virus intratumorally and determined the mortality of the tumor-bearing animals. Tumor regression and viral spread following virus injection were examined by histologic and immunocytochemical assays. RESULTS: In vitro, the tk(-) virus destroyed cultured 9L cell monolayers at multiplicities of infection of 0.1 and 1.0 within 48 hours. With the same quantity of virus, no remarkable difference in survival of neural cells was found. Foscarnet, an antiviral drug that acts independently of tk activity, blocked viral replication by greater than 99% at a concentration of 100 micrograms/mL. The mortality of animals bearing tumors declined with an increase in the amount of virus injected. Histologic examination showed that the HSV-1 treatment caused severe tumor regression. Immunocytochemistry using an anti-HSV-1 antibody revealed only a weak staining within the regressing tumors, and few immunopositive neurons were evident in the surrounding brain tissue. CONCLUSIONS: The results indicate that tk(-) HSV-1 mutants can selectively and effectively destroy glioma cells both in vitro and in vivo in normal, immunocompetent animals. IMPLICATIONS: Our failure to detect viral spread associated with regressing tumors suggests that some other cytopathic factors might be involved in the tumor regression. Regardless of the precise mode of tumor cell killing, HSV-1 may be useful for treating brain tumors.