Factors Associated with Statin Discontinuation Following Metabolic and Bariatric Surgery: A Retrospective Analysis of 2012-2021 Electronic Medical Records Network Data.

BACKGROUND: Bariatric surgery has been shown to improve hyperlipidemia, decreasing the need for statin medications. Although maintaining statin therapy post-surgery for those with a history of atherosclerotic cardiovascular disease (ASCVD) is advised, it is uncertain if discontinuation risks differ between those with and without ASCVD history. AIM: The study aims to analyze the rate and reasons for statin cessation post-bariatric surgery in the US using real-world data. METHODS: Using the TriNetX electronic medical records network from 2012 to 2021, the study involved patients aged 18 or older on statins at the time of bariatric surgery. They were categorized into primary and secondary prevention groups based on prior ASCVD. Statin discontinuation was defined as a 90-day gap post the last statin dosage. The Cox model assessed factors influencing statin cessation. RESULTS: Seven hundred and thirty-three statin users undergoing bariatric surgery were identified, with 564 (77%) in primary prevention. Six months post-surgery, 48% of primary prevention patients and 34.5% of secondary ones stopped statins. Primary prevention patients had a 30% higher likelihood of cessation compared to secondary prevention (hazard ratio, 1.30; 95% CI, 1.06-1.60) as shown by multivariable analysis. CONCLUSIONS: Post-bariatric surgery, primary prevention patients are more likely to discontinue statins than secondary prevention patients.

Surveillance Compliance and Quality of Life Assessment Among Surgical Patients with Familial Adenomatous Polyposis Syndrome.

BACKGROUND: Familial adenomatous polyposis (FAP) syndrome has a near-100% lifetime risk of colorectal cancer. Early surveillance and prophylactic surgery have been advocated to reduce this risk. However, the surveillance practices among FAP individuals in Saudi Arabia are unknown. We aimed to explore surveillance compliance in our population, as well as the disease impact on their quality of life (QoL). METHODS: All patients with FAP who underwent surgical resection at King Saud University Medical City between 2016 and 2022 were included. Demographic data, clinical features, family history, and compliance with surveillance were collected and analyzed. QoL questionnaires: Short-form health survey (SF-36) and European Organization for Research and Treatment (EORTC) were conducted by phone interview. RESULTS: A total of 14 patients were included with an average age of 25 years. Three patients (21.4%) were the first of their family members to develop FAP. Nine patients (64%) were untested for genetic mutation due to lack of referral to geneticists. The compliance rate toward both pre-operative colonoscopy and upper endoscopy were 78%. However, 38% and 27% compliance rates were observed toward initial and post-operative colonoscopy, respectively. The compliance rate was 14% toward thyroid ultrasound. QoL scores varied among patients, with a mean score above 60 across all SF-36 domains. CONCLUSION: An overall poor compliance was observed among our participants, particularly toward thyroid ultrasound. Increased health awareness and patient education are essential. In addition, the importance of surveillance and genetic counseling should be emphasized among physicians treating these patients.

5-year oncological outcomes in left-sided malignant colonic obstruction: stent as bridge to surgery.

BACKGROUND: A considerable number of patients with colon cancer present with a colonic obstruction. The use of self-expanding metallic stents (SEMS) as a bridge to surgery (BTS) in potential curative patients with left-sided colonic cancer obstruction remains debatable. Therefore, this study aimed to investigate the 5-year oncological outcomes of using a SEMS as a BTS. METHODS: All patients with left-sided malignant colon obstruction who underwent curative surgery with no metastasis upon presentation between March 2009 and May 2013 were retrospectively reviewed and analyzed. RESULTS: A total of 45 patients were included, 28 patients underwent upfront surgery, and 17 patients had a stent as a bridge to surgery. T4 stage was statistically significantly higher in patients who had a SEMS as a BTS (35.3% vs. 10.7%) (p-value 0.043). The mean duration in days of the SEMS to surgery was 13.76 (SD 10.08). TNM stage 3 was a prognostic factor toward distant metastasis (HR 5.05). When comparing patients who had upfront surgery to those who had a SEMS as a BTS, higher 5-year disease-free survival (75% vs. 72%) and 5-year overall survival (89% vs. 82%) were seen in patients who had upfront surgery. However, both were statistically insignificant. CONCLUSION: Using self-expanding metallic stents as a bridge to surgery yields comparable 5-year survival and disease-free survival rates to upfront emergency surgery. The decision to use SEMS versus opting for emergency surgery should be made after careful patient selection and with the assistance of experienced endoscopists. TRIAL REGISTRATION: N/A.

Oncological outcomes of elective versus emergency surgery for colon cancer: A tertiary academic center experience.

Background: In this study, we aimed to identify the oncological outcomes in colon cancer patients who underwent elective versus emergency curative resection. Methods: All patients who underwent curative resection for colon cancer between July 2015 and December 2019 were retrospectively reviewed and analyzed. Patients were divided into two groups based on the presentation into elective and emergency groups. Results: A total of 215 patients with colon cancer were admitted and underwent curative surgical resection. Of those, 145 patients (67.4%) were elective cases, and 70 (32.5%) were emergency cases. Family history of malignancy was positive in 44 patients (20.5%) and significantly more common in the emergency group (P = 0.016). The emergency group had higher T and TNM stages (P = 0.001). The 3-year survival rate was 60.9% and significantly less in the emergency group (P = 0.026). The mean duration from surgery to recurrence, 3-year disease-free survival, and overall survival were 1.19, 2.81, and 3.11, respectively. Conclusion: Elective group was associated with better 3-year survival, longer overall, and 3-year disease-free survival compared to the emergency group. The disease recurrence rate was comparable in both groups, mainly in the first two years after curative resection.

Evidence of Association between CTLA-4 Gene Polymorphisms and Colorectal Cancers in Saudi Patients.

Cytotoxic T lymphocyte antigen-4 (CTLA-4) has been identified as an immunosuppressive molecule involved in the negative regulation of T cells. It is highly expressed in several types of autoimmune diseases and cancers including colorectal cancer (CRC). (1) Objective: To explore the association between CTLA-4 single nucleotide polymorphisms (SNP) and risk to (CRC) in the Saudi population. (2) Methods: In this case-control study, 100 patients with CRC and 100 matched healthy controls were genotyped for three CTLA-4 SNPs: rs11571317 (-658C > T), rs231775 (+49A > G) and rs3087243 (CT60 G > A), using TaqMan assay method. Associations were evaluated using odds ratios (ORs) and 95% confidence intervals (95% CIs) for five inheritance models (co-dominant, dominant, recessive, over-dominant and log-additive). Furthermore, CTLA-4 expression levels were evaluated using quantitative real-time PCR (Q-RT-PCR) in colon cancer and adjacent colon tissues. (3) Results: Our result showed a significant association of the G allele (OR = 2.337, p < 0.0001) and GG genotype of the missense SNP +49A > G with increased risk of developing CRC in codominant (OR = 8.93, p < 0.0001) and recessive (OR = 16.32, p < 0.0001) models. Inversely, the AG genotype was significantly associated with decreased risk to CRC in the codominant model (OR = 0.23, p < 0.0001). In addition, the CT60 G > A polymorphism exhibited a strong association with a high risk of developing CRC for the AA genotype in codominant (OR = 3.323, p = 0.0053) and in allele models (OR = 1.816, p = 0.005). No significant association was found between -658C > T and CRC. The haplotype analysis showed that the G-A-G haplotype of the rs11571317, rs231775 and rs3087243 was associated with high risk for CRC (OR = 57.66; p < 0.001). The CTLA-4 mRNA gene expression was found significantly higher in tumors compared to normal adjacent colon samples (p < 0.001). (4) Conclusions: Our findings support an association between the CTLA-4 rs231775 (+49A > G) and rs3087243 (CT60 G > A) polymorphisms and CRC risk in the Saudi population. Further validation in a larger cohort size is needed prior to utilizing these SNPs as a potential screening marker in the Saudi population.

Rs10204525 Polymorphism of the Programmed Death (PD-1) Gene Is Associated with Increased Risk in a Saudi Arabian Population with Colorectal Cancer.

Checkpoint programmed death-1 (PD-1) has been identified as an immunosuppressive molecule implicated in the immune evasion of transformed cells. It is highly expressed in tumor cells in order to evade host immunosurveillance. In this study, we aimed to assess the association between single nucleotide polymorphisms (SNP) of PD-1 and the risk of colorectal cancer (CRC) in the Saudi population. For this case-control study, the TaqMan assay method was used for genotyping three SNPs in the PD-1 gene in 100 CRC patients and 100 healthy controls. Associations were estimated using odds ratios (ORs) and 95% confidence intervals (95% CIs) for multiple inheritance models (codominant, dominant, recessive, over-dominant, and log-additive). Moreover, PD-1 gene expression levels were evaluated using quantitative real-time PCR in colon cancer tissue and adjacent colon tissues. We found that the PD-1 rs10204525 A allele was associated with an increased risk of developing CRC (OR = 2.35; p = 0.00657). In addition, the PD-1 rs10204525 AA homozygote genotype was associated with a high risk of developing CRC in the codominant (OR = 21.65; p = 0.0014), recessive (OR = 10.97; p = 0.0015), and additive (OR = 1.98; p = 0.012) models. A weak protective effect was found for the rs2227981 GG genotype (OR = 2.52; p = 0.034), and no significant association was found between the rs2227982 and CRC. Haplotype analysis showed that the rs10204525, rs2227981, rs2227982 A-A-G haplotype was associated with a significantly increased risk of CRC (OR = 6.79; p =0.031).

The Anticancer Effects of the Pro-Apoptotic Benzofuran-Isatin Conjugate (5a) Are Associated With p53 Upregulation and Enhancement of Conventional Chemotherapeutic Drug Efficiency in Colorectal Cancer Cell Lines.

The present study aimed to investigate in-depth a cytotoxic novel benzofuran-isatin conjugate (5a, 3-methyl-N'-(2-oxoindolin-3-ylidene)benzofuran-2-carbohydrazide) with promising potential anticancer activities in colorectal adenocarcinoma HT29 and metastatic colorectal cancer (CRC) SW620 cell lines. Thus, the primary cell events involved in tumorigenicity, tumor development, metastasis, and chemotherapy response were explored. Both CRC cell lines were exposed to different concentrations of Compound 5a and then subjected to real-time cell viability, migration, and invasion assays, colony formation and cytotoxicity assays, and flow cytometry for cell cycle analysis and apoptosis determination. Western blot and RT-qPCR were performed to assess the protein and transcript expression levels of epithelial-mesenchymal transition (EMT), cell cycle, and apoptosis markers. We showed that the Compound 5a treatment exhibited anticancer effects through inhibition of HT29 and SW620 cell viability, migration, and invasion, in a dose-dependent manner, which were associated with the upregulation of the tumor suppressor p53. Compound 5a also inhibited the colony formation ability of HT29 and SW620 cells and reversed EMT markers E-cadherin and N-cadherin expression. CRC cell exposure to Compound 5a resulted in a cell cycle arrest at the G1/G0 phase in HT29 cells and at the G2/M phase in SW620 cells, along with the downregulation of cyclin A1 expression, described to be involved in the S phase entry. Furthermore, Compound 5a-induced apoptosis was associated with the downregulation of the anti-apoptotic Bcl-xl marker, upregulation of pro-apoptotic Bax and cytochrome c markers, and increased mitochondrial outer membrane permeability, suggesting the involvement of mitochondria-dependent apoptosis pathway. In addition, the combination studies of Compound 5a with the main conventional chemotherapeutic drugs 5-fluorouracil, irinotecan, and oxaliplatin showed a more potent cytotoxic effect in both CRC cells than a single treatment. In conclusion, our findings described the interesting in vitro anticancer properties of Compound 5a, shown to have possible antitumor, antimetastatic, and pro-apoptotic activities, with the enhancement of the cytotoxic efficiency of conventional chemotherapeutic drugs. In vivo studies are requested to confirm the promising anticancer potential of Compound 5a for CRC therapy.

A 66-Year-Old Man Presenting with Port-Site Metastatic Gastric Adenocarcinoma 4 Years After Laparoscopic Resection of a Rectal Adenocarcinoma.

BACKGROUND There is a recognized association between synchronous and metachronous colorectal and gastric adenocarcinoma. This report describes a 66-year-old man presenting with port-site metastatic gastric adenocarcinoma 4 years after laparoscopic resection of a rectal adenocarcinoma. CASE REPORT A 66-year-old male rectal cancer survivor presented to the clinic with a painless mass at the previous laparoscopic anterior resection port site. Physical examination revealed a soft port-site mass measuring 5×4 cm. Abdominal CT revealed enlargement of the right rectus abdominis muscle and thickening of the gastric fundus. A biopsy of the right abdominal wall mass revealed metastatic adenocarcinoma. Immunohistochemistry (IHC) testing was positive for cytokeratin 7 (CK7) and CDx2 and negative for cytokeratin 20 (CK20). The possible primary malignancy was upper gastrointestinal, and it was less likely to be colorectal in origin. Subsequently, the upper endoscopy revealed a friable, erythematous gastric mucosa. Biopsy revealed an invasive moderately differentiated gastric adenocarcinoma with positive IHC for CK7 and CDx2 and negative for CK20. The rectal adenocarcinoma pathology slides were reviewed, and IHC testing showed negative CK7 and positive CK20. Patient was known to have multiple comorbidities with poor functional status. The tumor board decision was made to manage him palliatively with best supportive care for the diagnosis of metastatic gastric cancer. CONCLUSIONS This report has presented a case of possible metachronous gastric adenocarcinoma with port-site metastasis following resection of a rectal adenocarcinoma. Clinicians should be aware of the association between synchronous and metachronous colorectal and gastric adenocarcinoma and the challenges associated with the diagnosis.

Targeting MUCL1 protein inhibits cell proliferation and EMT by deregulating ß­catenin and increases irinotecan sensitivity in colorectal cancer.

With >1.85 million cases and 850,000 deaths annually, colorectal cancer (CRC) is the third most common cancer detected globally. CRC is an aggressive malignancy with metastasis and, in spite of advances in improved treatment regimen, distant disease failure rates remain disappointingly high. Mucin­like 1 (MUCL1) is a small glycoprotein highly expressed mainly in breast cancer. The involvement of the MUCL1 protein in CRC progression and the underlying mechanism have been largely unknown. The aim of the present study was to investigate the MUCL1 expression profile and its functional significance in CRC. The Cancer Genome Atlas dataset revealed that MUCL1 expression was higher in colorectal tumor compared with normal tissues. MUCL1 was also revealed to be expressed in human CRC cell lines. The results demonstrated that MUCL1 promoted cell proliferation and colony formation, confirming its oncogenic potential. Silencing MUCL1 with short interfering RNA inhibited the protein expression of Bcl2 family proteins, such as Bcl2 and BclxL. Targeting MUCL1 resulted in significant inhibition in cell invasive and migratory behavior of HT­29 and SW620 cells. In addition, the expression of E­cadherin increased whereas the expression of vimentin decreased in MUCL1­silenced cells, confirming inhibition of epithelial­mesenchymal transition (EMT) process. Thus, it was revealed that MUCL1 plays a notable role in cell invasion and migration by inhibiting EMT in CRC. Mechanistically, MUCL1 drives ß­catenin activation by Ser­552 phosphorylation, nuclear accumulation and transcriptional activation. Targeting MUCL1 increases the drug sensitivity of CRC cells towards irinotecan. These findings thus demonstrated that MUCL1 acts as a modifier of other pathways that play an important role in CRC progression and MUCL1 was identified as a potential target for CRC therapeutics.

Community knowledge and awareness of colorectal cancer and screening tools: Community-based survey of 1,912 residents of Riyadh.

BACKGROUND: Participation in Colorectal cancer (CRC) screening programs is low in Saudi Arabia. Public awareness of CRC and knowledge of available screening tools are crucial for improving screening uptake. This study aimed to examine the level of awareness and knowledge of CRC among the Saudi population. MATERIALS AND METHODS: A survey-based study was conducted on 1912 residents of Riyadh, Saudi Arabia. The survey comprised 20 questions; these concerned the definition of the colon and rectum; the function of the colon; the incidence, risk factors, symptoms, screening methods, prevention methods, and treatment methods for CRC; and the value of early detection of CRC. RESULTS: Of the 1912 participants who completed the survey, only 51.7% knew that the colon was the large intestine, while 57% knew that the rectum was the end of the large intestine. Colonoscopy was the preferred screening tool (72.8%). Most respondents believed early detection of CRC through colonoscopy is associated with high survival rates. However, 65.7% of the participants reported that they would not like to undergo a CRC screening. Higher education level was also associated with knowledge that CRC can develop asymptomatically, with postgraduates most likely to know this (P = 0.032). CONCLUSIONS: There is a lack of knowledge regarding CRC among certain demographic groups in Saudi Arabia, and education and screening programs should target populations with the most limited knowledge.

Expression of VEGF, EGF and HGF in early- and late-stage colorectal cancer.

The heterogenous nature of colorectal cancer (CRC) highlights the need for a better understanding of the growth factors that affect tumour growth and cancer progression. The aim of the present study was to evaluate the role of epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) in the early (I and II) and late (III and IV) stages of CRC. The serum levels and mRNA expression (n=30) of the aforementioned growth factors were measured and immunohistochemistry (n=20) was performed in patients with CRC. Histological examination revealed comparable distribution of early-stage [I: 8 (26.7%) and II: 7 (23.3%)] and late-stage [III: 8 (26.7%) and IV: 7 (23.3%)] CRC. The mean serum concentrations of VEGF during the early (152.9±14.5 vs. 88.39±3.99 pg/ml; P=0.001) and late (182.7±25.8 vs. 88.39±3.99 pg/ml; P=0.002) stages were significantly higher compared with those in controls. Similarly, the mean serum concentrations of EGF in the early (409.4±7.96 vs. 153.7±13.8 pg/ml; P=0.05) and HGF in the late (90.4±17.4 vs. 56.9±4.97 pg/ml; P=0.05) stages were significantly higher compared with those in controls. The serum concentrations of VEGF, EGF and HGF were comparable between the early and late stages of CRC. Compared to normal tissues, the mRNA expression of both VEGF (P<0.001) and HGF (P<0.01) was upregulated in early-stage and downregulated in late-stage CRC. The expression of EGF remained significantly elevated during both the early and late stages of CRC (P<0.01). Histopathological analyses confirmed increased expression of VEGF in cancerous tissues compared with that in normal tissues. The present study emphasized the need for monitoring the serum levels and tissue expression of growth factors to fully elucidate their role in patients with CRC.

Prevalence of vasovagal syncope following bariatric surgery.

BACKGROUND: Obesity is a major global public health problem. Observational studies have shown an increasing incidence of syncope and pre-syncope following bariatric surgery in obese patients. However, there is paucity of the true incidence of syncope following bariatrics sugary in the literature. METHODS: We have randomly surveyed 200 patients who underwent bariatric surgery between 2016-2018 using Calgary Syncope Score (CSS). RESULTS: Of the 200 patients enrolled, 107 (53.5%) were female with 167 patients (83.5%) between 18 and 50 years of age. The most-reported comorbidities were diabetes mellitus 26 (13%) hypertension 25 (12.5%) and pulmonary disease 18 (9%). The majority 98 (49%) of the patients had pre-operative body mass index (BMI) of 40-50 kg/m 2, and most of them had laparoscopic sleeve gastrectomy (LSG). Sixty-two (31%) patients had vasovagal syncope (VVS), 52 (26%) patients had non-VVS and 86 (43%) had no syncope. CONCLUSION: Vasovagal syncope in patients following bariatric sugary is quite common and affects 15% of bariatric patients in our series in the first year postoperatively. Further randomized controlled trials are required to prove our results.

Emerging trends in colorectal cancer: Dysregulated signaling pathways (Review).

Colorectal cancer (CRC) is the third most frequently detected type of cancer, and the second most common cause of cancer­related mortality globally. The American Cancer Society predicted that approximately 147,950 individuals would be diagnosed with CRC, out of which 53,200 individuals would succumb to the disease in the USA alone in 2020. CRC­related mortality ranks third among both males and females in the USA. CRC arises from 3 major pathways: i) The adenoma­carcinoma sequence; ii) serrated pathway; and iii) the inflammatory pathway. The majority of cases of CRC are sporadic and result from risk factors, such as a sedentary lifestyle, obesity, processed diets, alcohol consumption and smoking. CRC is also a common preventable cancer. With widespread CRC screening, the incidence and mortality from CRC have decreased in developed countries. However, over the past few decades, CRC cases and mortality have been on the rise in young adults (age, <50 years). In addition, CRC cases are increasing in developing countries with a low gross domestic product (GDP) due to lifestyle changes. CRC is an etiologically heterogeneous disease classified by tumor location and alterations in global gene expression. Accumulating genetic and epigenetic perturbations and aberrations over time in tumor suppressor genes, oncogenes and DNA mismatch repair genes could be a precursor to the onset of colorectal cancer. CRC can be divided as sporadic, familial, and inherited depending on the origin of the mutation. Germline mutations in APC and MLH1 have been proven to play an etiological role, resulting in the predisposition of individuals to CRC. Genetic alterations cause the dysregulation of signaling pathways leading to drug resistance, the inhibition of apoptosis and the induction of proliferation, invasion and migration, resulting in CRC development and metastasis. Timely detection and effective precision therapies based on the present knowledge of CRC is essential for successful treatment and patient survival. The present review presents the CRC incidence, risk factors, dysregulated signaling pathways and targeted therapies.

Short-term outcomes after self-expandable metal stent insertion for obstructing colon cancer: a retrospective cohort study.

BACKGROUND: Self-expanding metal stents (SEMS) are used as a bridge to surgery for colon cancer patients as an alternative to emergency surgery. Currently, there is a paucity of literature from Saudi Arabia on the preoperative usage of SEMS. OBJECTIVE: Determine whether SEMS are associated with a higher rate of complications. DESIGN: Retrospective cohort study SETTINGS: Tertiary care hospital in Saudi Arabia. PATIENTS AND METHODS: In patients diagnosed with obstructing colon cancer, up-front surgical resection was compared with insertion of SEMS followed by surgical resection between the years 2009 and 2013. MAIN OUTCOME MEASURES: Rate of stent-related short-term complications. Secondary endpoint, postoperative complications. SAMPLE SIZE: 65. RESULTS: Twenty-four (36.9%) patients underwent SEMS placement; 41 (63.1%) underwent primary surgery. The median (interquartile range) hospital stay was significantly higher among the SEMS group (13 [8.5] days versus 7 [3] days in the primary surgery group, P<.001). Five patients (20.8%) in the SEMS group developed complications: 2 (8.3%) perforations, 2 (8.3%) obstructions, and 1 (4.2%) stent migrations. CONCLUSION: SEMS is associated with longer hospital stays and short-term serious complications. Further research should be conducted, preferably with a larger sample size. LIMITATIONS: Retrospective design, small sample size. CONFLICT OF INTEREST: None.

Impact of COVID-19 pandemic on patient satisfaction and surgical outcomes: A retrospective and cross sectional study.

OBJECTIVE: The objective of this study was to evaluate the impact of the COVID-19 pandemic on patient satisfaction and surgical outcomes at King Khalid University Hospital in Saudi Arabia. BACKGROUND: The COVID-19 pandemic has greatly affected health care systems across developing and developed countries. Therefore, it is important to understand its impact on various parameters of patient care as regards revised infrastructure and policies in hospitals during the pandemic. METHOD: It is a retrospective cross-sectional study was conducted from 13-3-2020 to 26-4-2020 at King Khalid University Hospital in Saudi Arabia. Patient satisfaction and surgical outcomes were the main outcome measures. RESULTS: 331 participants were included in the study (median age: 53 years; 70% female), and 223 completed the patient's satisfaction survey. 260 of the surgeries were non-oncolog cases (78.6%) compared to 71 oncology cases (21.4%). With respect to the surgical outcomes, 12% of the patients required admission to the ICU, and 10.9% developed postoperative complications, most of which were infectious complications. Only 1.8% (6 patients) were re-admitted to the hospital. Three patients died within 30 days post-op (0.9%), all had emergency surgery. Regarding patient satisfaction, 77.6% and 93% of the patients reported that nurses and doctors, respectively, treated them with courtesy and respect, listened to them carefully, and provided clear explanations to them. 90.3% were satisfied with the hospital sanitary measures. 64.1% stated that they got written instructions at the time of discharge. CONCLUSION: The satisfaction level of patients was high for all the studied domains, and there were a small number of complications with overall good surgical outcomes. That indicates that all the actions and policies that were implemented during the pandemic were proven beneficial for the patients. It is recommended to continue those measures until the COVID-19 pandemic is over.

Correction to: A novel coordination complex of platinum (PT) induces cell death in colorectal cancer by altering redox balance and modulating MAPK pathway.

An amendment to this paper has been published and can be accessed via the original article.

A novel coordination complex of platinum (PT) induces cell death in colorectal cancer by altering redox balance and modulating MAPK pathway.

BACKGROUND: Colorectal cancer (CRC) is a heterogeneous tumor having various genetic alterations. The current treatment options had limited impact on disease free survival due to therapeutic resistance. Novel anticancer agents are needed to treat CRC specifically metastatic colorectal cancer. A novel coordination complex of platinum, (salicylaldiminato)Pt(II) complex with dimethylpropylene linkage (PT) exhibited potential anti-cancer activity. In this study, we explored the molecular mechanism of PT-induced cell death in colorectal cancer. METHODS: Colony formation was evaluated using the clonogenic assay. Apoptosis, cell cycle analysis, reactive oxygen species, mitochondrial membrane potential and caspase-3/- 7 were assessed by flow cytometry. Glutathione level was detected by colorimetric assay. PT-induced alteration in pro-apoptotic/ anti-apoptotic proteins and other signaling pathways were investigated using western blotting. P38 downregulation was performed using siRNA. RESULTS: In the present study, we explored the molecular mechanism of PT-mediated inhibition of cell proliferation in colorectal cancer cells. PT significantly inhibited the colony formation in human colorectal cancer cell lines (HT-29, SW480 and SW620) by inducing apoptosis and necrosis. This platinum complex was shown to significantly increase the reactive oxygen species (ROS) generation, depletion of glutathione and reduced mitochondrial membrane potential in colorectal cancer cells. Exposure to PT resulted in the downregulation of anti-apoptotic proteins (Bcl2, BclxL, XIAP) and alteration in Cyclins expression. Furthermore, PT increased cytochrome c release into cytosol and enhanced PARP cleavage leading to activation of intrinsic apoptotic pathway. Moreover, pre-treatment with ROS scavenger N-acetylcysteine (NAC) attenuated apoptosis suggesting that PT-induced apoptosis was driven by oxidative stress. Additionally, we show that PT-induced apoptosis was mediated by activating p38 MAPK and inhibiting AKT pathways. This was demonstrated by using chemical inhibitor and siRNA against p38 kinase which blocked the cytochrome c release and apoptosis in colorectal cancer cells. CONCLUSION: Collectively, our data demonstrates that the platinum complex (PT) exerts its anti-proliferative effect on CRC by ROS-mediated apoptosis and activating p38 MAPK pathway. Thus, our findings reveal a novel mechanism of action for PT on colorectal cancer cells and may have therapeutic implication.

Long-term outcomes after complete mesocolic excision for colon cancer at a tertiary care center in Saudi Arabia.

BACKGROUND: Data on long-term survival and recurrence of cancer after complete mesocolic excision (CME) for colon cancer has not been reported from our center and related to international data. OBJECTIVE: Describe overall and disease-free survival, survival by surgery site and stage, and recurrence rates after curative surgery. DESIGN: Retrospective chart review. SETTINGS: Academic tertiary care center. PATIENTS AND METHODS: The study included all patients who underwent either laparoscopic or open surgery for colon cancer with curative intent between 2001 and 2011. The colorectal database was reviewed for the following: demographic data, comorbidities, radiologic investigations, clinical stage, type of operation, complications, pathologic assessment, adjuvant treatment, recurrence and survival. Survival and recurrence rates were calculated, and survival curves were generated. MAIN OUTCOME MEASURES: 5-year overall survival, secondary endpoints were 5-year disease-free survival, survival by surgery site and stage, and recurrence rates. SAMPLE SIZE: 220. RESULTS: The mean (SD) age at diagnosis was 57 (13) years (CI 95%: 55-59 years). There were 112 males. Mean (SD) body mass index was 27.6 (5.7) kg/m2 (CI 95%: 27-28). Pathological assessment revealed R0 (microscopically margin-negative) resection in 207 (94%). The overall 5-year survival and disease-free survival was 77.9% and 70%, respectively. The 5-year disease-free survival was 69% for the sigmoid/left colon and 69% for the right colon (difference statistically nonsignificant). Stages at the time of resection were stage 0 for 2 (0.01%) patients, stage I for 18 (8%), stage II for 92 (42%), stage III for 100 (46%), and stage IV for 6 (3%). The 5-year overall survival by stages I, II, III and IV was 94%, 80%, 75% and 50%, respectively (difference statistically non-significant). The overall 5-year recurrence rate was 23.4%. CONCLUSION: The outcomes of surgical treatment for colon cancer at our institution are equivalent to international sites. No difference was noted between left and right colon in terms of survival after CME. LIMITATIONS: Single center, retrospective, small sample size. CONFLICT OF INTEREST: None.

Herbal melanin inhibits colorectal cancer cell proliferation by altering redox balance, inducing apoptosis, and modulating MAPK signaling.

BACKGROUND: Colorectal carcinoma is one of the most deadly cancers that requests effective and safe chemotherapy. Evaluation of natural product-based anticancer drugs as adjuvant treatment with fewer side effects is largely unexplored research fields. Herbal melanin (HM) is an extract of the seed coats of Nigella sativa that modulates an inflammatory response through toll-like receptor 4 (TLR4). This TLR4 receptor is also involved in the modulation of apoptosis. We therefore explored the anticancer potential of HM and specifically its effect on the molecular mechanisms underlying adenocarcinoma and metastatic colorectal cancer (mCRC) cell death in vitro. METHODS: Cell viability was evaluated using the MTT assay. Cellular reactive oxygen species (ROS), glutathione levels, and apoptotic status were assessed using fluorometric and colorimetric detection methods. HM-induced apoptotic and other signaling pathways were investigated using Western blot technology and mitochondrial transition pore assay kit. TLR4 receptor downregulation and blockade were performed using siRNA technology and neutralizing antibody, respectively. RESULTS: Our results showed that HM inhibited the proliferation of the colorectal adenocarcinoma HT29 and mCRC SW620 cell lines. Furthermore, HM enhanced ROS production and decreased glutathione levels. HM-induced apoptosis was associated with mitochondrial outer membrane permeability and cytochrome c release, inhibition of the Bcl2 family proteins, and activation of caspase-3/-7. In addition, HM modulated MAPK pathways by activating the JNK pathway and by inhibiting ERK phosphorylation. TLR4 receptor downregulation enhanced HM-induced apoptosis while TLR4 receptor blockade partially alleviated HM-inhibited ERK phosphorylation. CONCLUSION: Altogether, these findings indicate that HM exerts pro-apoptotic effects and inhibits MAPK pathway through TLR4 in mCRC and colorectal adenocarcinoma cells, suggesting HM as a promising natural-based drug for the treatment of colorectal cancer.

Induction of ROS­mediated cell death and activation of the JNK pathway by a sulfonamide derivative.

The emergence of colorectal cancer in developed nations can be attributed to dietary habits, smoking, a sedentary lifestyle and obesity. Several treatment regimens are available for primary and metastatic colorectal cancer; however, these treatment options have had limited impact on cure and disease­free survival, and novel agents need to be developed for treating colorectal cancer. Thus, the objective of this study was to explore the anticancer mechanism of a benzo(1,3)dioxol­based derivative of sulfonamide. The compound's inhibitory effect on cell proliferation was determined using the MTT assay and the xCelligence RTDP machine. Alternations in the expression of Bcl­2 and inhibitor of apoptosis protein families were detected by western blotting. Apoptotic marker protein expression, including cytochrome c and cleaved poly(ADP­ribose)polymerase was measured in the cytosolic extract of cells. Apoptosis and necrosis were detected by flow cytometry and immunofluorescence. Reactive oxygen species (ROS), and activation of caspase­3 and caspase­7 were measured using flow cytometry. Activation of the JNK pathway was detected by western blotting. We investigated the molecular mechanism of action of the sulfonamide derivative on colorectal cancer cells and found that the compound possesses a potent anticancer effect, which is primarily exerted by inducing apoptosis and necrosis. Interestingly, this compound exhibited little antiproliferative effect against the normal colonic epithelial cell line FHC. Furthermore, our results showed that the compound could significantly increase ROS production. Apoptosis induction could be attenuated by the free oxygen radical scavenger N­acetyl cysteine (NAC), indicating that the antiproliferative effect of this compound on colorectal cancer cells is at least partially dependent on the redox balance. In addition, JNK signaling was activated by treatment with this derivative, which led to the induction of apoptosis. On the contrary, a JNK inhibitor could suppress the cell death induced by this compound. Our findings thus suggested a novel anticancer mechanism of a benzo(1,3)dioxol­based derivative of sulfonamide for colorectal cancer cells and may have therapeutic potential for the treatment of colorectal cancer; however, further investigation is required.