Experimental investigation for nonalcoholic fatty pancreas management using probiotics.

BACKGROUND: Nonalcoholic fatty pancreatitis (NAFP) presents a pressing challenge within the domain of metabolic disorders, necessitating further exploration to unveil its molecular intricacies and discover effective treatments. Our focus was to delve into the potential therapeutic impact of ZBiotic, a specially engineered strain of probiotic B. subtilis, in managing NAFP by targeting specific genes linked with necroptosis and the TNF signaling pathway, including TNF, ZBP1, HSPA1B, and MAPK3, along with their upstream epigenetic regulator, miR-5192, identified through bioinformatics. METHODS: Rats were subjected to either a standard or high-fat, high-sucrose diet (HFHS) for eight weeks. Subsequently, they were divided into groups: NAFP model, and two additional groups receiving daily doses of ZBiotic (0.5 ml and 1 ml/kg), and the original B. subtilis strain group (1 ml/kg) for four weeks, alongside the HFHS diet. RESULTS: ZBiotic exhibited remarkable efficacy in modulating gene expression, leading to the downregulation of miR-5192 and its target mRNAs (p < 0.001). Treatment resulted in the reversal of fibrosis, inflammation, and insulin resistance, evidenced by reductions in body weight, serum amylase, and lipase levels (p < 0.001), and decreased percentages of Caspase and Nuclear Factor Kappa-positive cells in pancreatic sections (p < 0.01). Notably, high-dose ZBiotic displayed superior efficacy compared to the original B. subtilis strain, highlighting its potential in mitigating NAFP progression by regulating pivotal pancreatic genes. CONCLUSION: ZBiotic holds promise in curbing NAFP advancement, curbing fibrosis and inflammation while alleviating metabolic and pathological irregularities observed in the NAFP animal model. This impact was intricately linked to the modulation of necroptosis/TNF-mediated pathway-related signatures.

Rosavin improves insulin resistance and alleviates hepatic and kidney damage via modulating the cGAS-STING pathway and autophagy signaling in HFD/STZ-induced T2DM animals.

Background: Inflammation-mediated insulin resistance in type 2 diabetes mellitus (T2DM) increases complications, necessitating investigation of its mechanism to find new safe therapies. This study investigated the effect of rosavin on the autophagy and the cGAS-STING pathway-related signatures (ZBP1, STING1, DDX58, LC3B, TNF-α) and on their epigenetic modifiers (miR-1976 and lncRNA AC074117.2) that were identified from in silico analysis in T2DM animals. Methods: A T2DM rat model was established by combining a high-fat diet (HFD) and streptozotocin (STZ). After four weeks from T2DM induction, HFD/STZ-induced T2DM rats were subdivided into an untreated group (T2DM group) and three treated groups which received 10, 20, or 30 mg per kg of R. rosea daily for 4 weeks. Results: The study found that rosavin can affect the cGAS-STING pathway-related RNA signatures by decreasing the expressions of ZBP1, STING1, DDX58, and miR-1976 while increasing the lncRNA AC074117.2 level in the liver, kidney, and adipose tissues. Rosavin prevented further weight loss, reduced serum insulin and glucose, improved insulin resistance and the lipid panel, and mitigated liver and kidney damage compared to the untreated T2DM group. The treatment also resulted in reduced inflammation levels and improved autophagy manifested by decreased immunostaining of TNF-α and increased immunostaining of LC3B in the liver and kidneys of the treated T2DM rats. Conclusion: Rosavin has shown potential in attenuating T2DM, inhibiting inflammation in the liver and kidneys, and improving metabolic disturbances in a T2DM animal model. The observed effect was linked to the activation of autophagy and suppression of the cGAS-STING pathway.

Comprehensive machine learning models for predicting therapeutic targets in type 2 diabetes utilizing molecular and biochemical features in rats.

Introduction: With the increasing prevalence of type 2 diabetes mellitus (T2DM), there is an urgent need to discover effective therapeutic targets for this complex condition. Coding and non-coding RNAs, with traditional biochemical parameters, have shown promise as viable targets for therapy. Machine learning (ML) techniques have emerged as powerful tools for predicting drug responses. Method: In this study, we developed an ML-based model to identify the most influential features for drug response in the treatment of type 2 diabetes using three medicinal plant-based drugs (Rosavin, Caffeic acid, and Isorhamnetin), and a probiotics drug (Z-biotic), at different doses. A hundred rats were randomly assigned to ten groups, including a normal group, a streptozotocin-induced diabetic group, and eight treated groups. Serum samples were collected for biochemical analysis, while liver tissues (L) and adipose tissues (A) underwent histopathological examination and molecular biomarker extraction using quantitative PCR. Utilizing five machine learning algorithms, we integrated 32 molecular features and 12 biochemical features to select the most predictive targets for each model and the combined model. Results and discussion: Our results indicated that high doses of the selected drugs effectively mitigated liver inflammation, reduced insulin resistance, and improved lipid profiles and renal function biomarkers. The machine learning model identified 13 molecular features, 10 biochemical features, and 20 combined features with an accuracy of 80% and AUC (0.894, 0.93, and 0.896), respectively. This study presents an ML model that accurately identifies effective therapeutic targets implicated in the molecular pathways associated with T2DM pathogenesis.

Antioxidative and Anti-Inflammatory Protective Effects of Fucoxanthin against Paracetamol-Induced Hepatotoxicity in Rats.

Paracetamol or acetaminophen (PAC) is a commonly used analgesic and antipyretic drug. It has been shown that overdoses beyond the therapeutic range can cause hepatotoxicity and acute liver injury. The most common cause of drug-induced liver injury (DILI) in Saudi Arabia and worldwide is paracetamol overdose. Fucoxanthin (FUC) is an allenic carotenoid that is found in edible brown seaweeds, and it has antioxidant and anti-inflammatory effects. Several studies have shown the potential therapeutic effects of FUC in diabetes, cancers, and inflammatory disorders. This study aims to investigate the protective effect of FUC against PAC-induced acute liver injury in rats. FUC was administered (100, 200, and 500 mg/kg, p.o.) for 7 days, and then the liver injury was induced by the administration of PAC (2000 mg/kg, oral). Blood and liver tissue samples were collected from PAC-positive untreated, treated, and negative control rats. Biochemical and inflammatory parameters in the blood were measured. In addition, RT-PCR, Western blotting, and immunohistochemistry were performed for liver tissue. The serum levels of liver biomarkers (ALT, AST, and ALP) increased after PAC-induced liver toxicity; FUC-treated rats showed lower levels compared to the positive control. There was an increase in the expression of TNF-α, IL-1, IL-6, NF-kB, INF-γ, and iNOS and a decrease in IL-10, IL-22, and IL-10R expression after the FUC treatment of injured liver rats. For the hepatic inflammation and PAC-toxicity-induced oxidative stress genes and proteins, FUC-treated rats (100, 200, and 500 mg/kg) showed a reduction in the expression of oxidative stress genes. These results showed that FUC protected the liver against PAC-induced injury through antioxidant and anti-inflammatory actions. However, further clinical studies are required to confirm the findings.

The Potential Role of Circulating Long Miscellaneous RNAs in the Diagnosis and Prognosis of Hepatitis C Related Hepatocellular Carcinoma.

Ribonucleic acids (RNAs) are important regulators of gene expression and crucial for the progression of hepatocellular carcinoma (HCC). This study was designed to determine the diagnostic and prognostic utility of the circulating long miscellaneous RNAs; LINC01419, AK021443, and AF070632 in HCV-related HCC patients. Real-time PCR was used to measure their relative expression levels in the plasma of 194 HCV patients, 120 HCV-related HCC patients and 120 healthy controls. LINC01419 and AK021443 expression levels had significantly increasing linear trend estimates while AF070632 was dramatically downregulated in HCC compared to HCV. Interestingly, LINC01419 and AK021443 served as more significant diagnostic biomarkers for HCC than AF070632 and AFP. Multivariate analysis with cox regression revealed that the high expression of AK021443 [HR = 10.06, CI95%: 3.36-30.07], the high expression of LINC01419 [HR 4.13, CI95%: 1.32-12.86], and the low expression of AF070632 [HR = 2.70, CI95%: 1.07-6.81] were significant potential prognostic factors for HCC. Besides, the Kaplan-Meier analysis showed that HCC patients with high LIN01419 and AK021443 and low AF070632 expression levels had shorter OS. The circulating LINC01419 and AK021443 can be used as noninvasive potential biomarkers for diagnosis and prognosis of HCV-related HCC patients than AF070632 providing new targets for limiting the progression of the disease.

Investigation of Hyperlipidemia Associated with Increased Levels of Oxidized Low-Density Lipoproteins and 8-Hydroxy-2´-Deoxyguanosine.

Background: Hyperlipidemia is a common risk factor for atherosclerosis, heart diseases, and other pathological conditions. The factors leading to the oxidation of native low-density lipoproteins remain of valuable importance for a better understanding of the mechanisms leading to these pathologies. The aim of the present study was to evaluate the association between lipid status and the levels of oxidized low-density lipoproteins and 8-hydroxy-2´-deoxyguanosine. Methods: One hundred and fourteen participants were enrolled. Lipid profile parameters were measured and used individually to categorize subjects into two groups of normal and hyperlipidemic cases according to the international reference ranges. Oxidized low-density lipoproteins and 8-hydroxy-2´-deoxyguanosine were then compared in normal and high lipid profile groups. The obtained results were then statistically analyzed. Results: 8-Hydroxy-2´-deoxyguanosine was found to be positively correlated with hypercholesterolemia, hypertriglyceridemia, and high levels of low-density lipoproteins (r = 0.53, 0.41, and 0.60), respectively (p<0.001). A positive correlation was observed also between the levels of oxidized low-density lipoproteins and the same lipid profile parameters (r = 0.42, 0.31, and 0.45), respectively (p<0.001). Conclusion: The present study suggests that disturbance in lipid profile may result in increased levels of oxidized low-density lipoproteins and oxidative stress in the study group; however, a larger sample is needed to confirm the present findings.

The Potential Utility of Circulating Oncofetal H19 Derived miR-675 Expression versus Tissue lncRNA-H19 Expression in Diagnosis and Prognosis of HCC in Egyptian Patients.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Interestingly, lncRNA-H19 acts independently in HCC and influences miR-675 expressions. We aimed to assess the potential utility of tissue lncRNA-H19 versus miR-675 expressions as a non-invasive biomarker for HCC diagnosis and prognosis in Egyptian patients. Ninety-one HCC patients and 91 controls included in this study were investigated for expression of lncRNA-H19 and miR675 using RT-qPCR. Our results showed that the expression of lncRNA-H19 and microRNA-675 were higher in patients than in controls (p < 0.001 for both). Additionally, lncRNA-H19 expression was higher in tumorous than in non-tumorous tissue (p < 0.001). Linear regression revealed that miR-675 expression was a significantly higher positive predictor than lncRNA-H19 for tumor size, pathologic grade, and AFP level; similarly, for cyclin D1 and VEGF protein expression. By using the ROC curve, the sensitivity of miR-675 was higher than lncRNA-H19 for discriminating HCC from controls (95-89%, respectively) and the sensitivity of lncRNA-H19 was higher in tumorous than in non-tumorous tissues (76%). The high expressions of both were associated with low OS (p < 0.001, 0.001, respectively). Oncofetal H19-derived miR-675 expression could be considered a potential noninvasive diagnostic and prognostic biomarker, outstanding the performance of the expression of tissue lncRNA-H19 for HCC.

Potential Value of TNF-α (-376 G/A) Polymorphism and Cystatin C (CysC) in the Diagnosis of Sepsis Associated Acute Kidney Injury (S-AK I) and Prediction of Mortality in Critically Ill patients.

Sepsis Associated Kidney Injury represents a major health concern as it is frequently associated with increased risk of mortality and morbidity. We aimed to evaluate the potential value of TNF-α (-376 G/A) and cystatin C in the diagnosis of S-AKI and prediction of mortality in critically ill patients. This study included 200 critically ill patients and 200 healthy controls. Patients were categorized into 116 with acute septic shock and 84 with sepsis, from which 142 (71%) developed S-AKI. Genotyping of TNF-α (-376 G/A) was performed by RT-PCR and serum CysC was assessed by Enzyme Linked Immunosorbent Assay. Our results showed a highly significant difference in the genotype frequencies of TNF-α (-376 G/A) SNP between S-AKI and non-AKI patients (p < 0.001). Additionally, sCysC levels were significantly higher in the S-AKI group (p = 0.011). The combination of both sCysC and TNF-α (-376 G/A) together had a better diagnostic ability for S-AKI than sCysC alone (AUC = 0.610, 0.838, respectively). Both GA and AA genotypes were independent predictors of S-AKI (p= < 0.001, p = 0.002 respectively). Additionally, sCysC was significantly associated with the risk of S-AKI development (Odds Ratio = 1.111). Both genotypes and sCysC were significant predictors of non-survival (p < 0.001), suggesting their potential role in the diagnosis of S-AKI and prediction of mortality.

Evaluation of the Diagnostic and Predicative Values of 8-Iso-Prostaglandin F2α as a Biomarker of Breast Cancer.

BACKGROUND: Breast cancer (BC) is a commonly reported cancer that is widely prevalent among women. Its early detection improves patient survival and results in better outcomes. For diagnosis and follow-up care, tumor markers are one of the feasible investigations to be ordered. 8-Iso-prostaglandin F2α (8-iso-PGF2α) serves as a serum marker reflecting oxidative stress and subsequent damaging of DNA. In the present study, we aimed to evaluate both diagnostic and predictive values of 8-iso-PGF2α in BC patients. MATERIALS AND METHODS: Serum levels of 8-iso-PGF2α were assessed for 66 women with benign breast tumors and 65 women who had malignant BC. To compare the patients who had breast tumors with healthy individuals, 63 women free of breast diseases were selected as controls. RESULTS: The serum level of 8-iso-PGF2α in the BC patients (57.92 pg/mL) was significantly higher compared to those with benign tumors (18.89 pg/mL) (p < 0.001). In addition, individuals with no breast diseases had less 8-iso-PGF2α (4.02 pg/mL) compared to those who had developed a tumor (p < 0.001). Serum 8-iso-PGF2α was found to be positively correlated with both carcinoembryonic antigen (r = 0.74, p < 0.001) and cancer antigen 15-3 (r = 0.80, p < 0.001). Furthermore, serum 8-iso-PGF2α showed high diagnostic performance in BC (AUC = 0.999, sensitivity = 100%, specificity = 99.2% at a cutoff value of 36.18 pg/mL). CONCLUSIONS: Our study found that the high level of serum 8-iso-PGF2α helps to provide a non-invasive indicator to detect BC. Future work with a larger sample size and various phases of BC can confirm the current results which provide insights into the early detection of cancer.

Whole exome sequencing detects novel variants in Saudi children diagnosed with eczema.

BACKGROUND: Eczema is also known as atopic dermatitis is well-known for the skin disease globally. In Saudi Arabia, exome sequencing studies have not been documented. The purpose of this study was to scrutinize the disease causing mutations in children affected with eczema with exome sequencing in the Saudi population. METHODS: We recruited randomly three sporadic cases of children diagnosed with eczema and simultaneously, three more cases were adopted for control samples. Exome sequencing was carried out by applying a pipeline that captures all the variants of concern related to the samples by using the Ion torrent. RESULTS: In this study, we have documented 49 variants, among which 37 variants were confirmed through eczema children and remaining 30 variants through control children. However, from the analysis of the 6 samples, we have identified rs10192157 (1646C>T; Thr549Ile), rs2899642 (27C>G; Asn9Lys), chr1:152127950 (1625G>A; Gly542Asp) and chr1:152128041 (1534C>G; Gly512Arg) variants which are rarely linked to the disease eczema. In the rs10192157, we have documented these mutations in all three eczema children and one in the control; the rs2899642 mutation appeared in only a couple of eczema children, whereas the mutation in the chr1:152127950 regions appeared in only one eczema patient. However, the chr1:152128041 mutations appeared in only one case of eczema and also in two control children. CONCLUSION: Our study revealed four mutations which had not previously been connected with eczema within the database. However, the rs10192157 and rs2899642 mutations were documented with asthma disease. The remaining mutations such as chr1:152127950 and chr1:152128041 have not been reported anywhere else. This study recommends screening these 4 mutations in eczema cases and their relevant controls to confirm the prevalence in the Saudi population. It is recommended that future studies examine the 4 mutations in detail.

8-Hydroxy-2'-deoxyguanosine as a Discriminatory Biomarker for Early Detection of Breast Cancer.

BACKGROUND: Breast cancer (BC) is one of the most prevalent and reported cancers among Saudi women. Detection of BC in the early invasive stage (stages I, II) has an advantage in treating patients over detection in the late invasive stage (stages III, IV). Tumor markers are used to aid in diagnosis, treatment monitoring, and recurrence detection of malignant tumors. 8-hydroxy-2'-deoxyguanosine (8-OHdG) is a marker of nucleic damage owing to oxidative stress. PATIENTS AND METHODS: We studied the blood levels of 8-OHdG in 50 women with benign breast tumors, 50 women with BC, and 50 healthy women as a control group. RESULTS: The concentrations of 8-OHdG were significantly increased in the BC group (55.2 ng/dL) compared with the benign tumor group (30.2 ng/dL) and with the healthy control group (9.08 ng/dL). The same pattern was observed with other diagnostic markers, including carcinoembryonic antigen and cancer antigen 15-3. Significant positive correlations between 8-OHdG and both carcinoembryonic antigen (r = 0.63; P < .001) and cancer antigen 15-3 (r = 0.51; P < .001) were noticed. The levels of 8-OHdG were significantly higher in stage I (81 ng/dL) compared with stage II (51 ng/dL; P < .05), stage III (38 ng/dL; P < .01), and stage IV (19 ng/dL; P < .001). In addition, serum 8-OHdG had a high diagnostic performance in BC (area under the curve, 0.86; sensitivity = 82%; specificity = 80% at cutoff value 21.4 ng/mL). 8-OHdG is associated with BC risk according to logistic regression analysis. CONCLUSION: We concluded that the significant increase of serum levels of 8-OHdG in patients with BC can be used as a potential noninvasive biomarker for early detection of BC. However, large sample sizes from different stages and types of BC should be included in any future study to confirm the present findings before translating the findings into routine clinical application.

Correction to: Assessment of tumor necrosis factor alpha polymorphism TNF-α-238 (rs 361525) as a risk factor for development of acute kidney injury in critically ill patients.

The title of the original article has been corrected to: Assessment of tumor necrosis factor alpha polymorphism TNF-α-238 (rs 361525) as a risk factor for development of acute kidney injury in critically ill patients. The original article has been corrected to reflect the correct title.

Assessment of tumor necrosis factor alpha polymorphism TNF-α-238 (rs 361525) as a risk factor for development of acute kidney injury in critically ill patients.

Critically ill patients revealed significant adverse outcomes (sepsis, septic shock, organ dysfunction/failure, and mortality) despite variable effort. AIM: this study evaluated the association of TNF-a-238 (rs 361525) with adverse outcomes in critically ill patients. TNF-α-238 (rs 361525) SNP was performed by RT-PCR on 200 critically-ill patients (112 had severe sepsis and septic shock and 88 were septic), 127 of them had AKI. Urinary N-acetyl-ß-(D)-glucosaminidase and serum creatinine were assessed by modified Jaffé and ELISA respectively. These results revealed that heterozygous genotype GA of TNF-α-238 (rs 361525) SNP significantly increased the risk of adverse-outcome (mortality rate) (P = 0.0001; OR 8.9), regardless of organ dysfunction (P = 0.09) or severity of sepsis (P = 0.6). Moreover, heterozygous genotype GA of TNF-α-238 (rs 361525) SNP was significantly associated with inflammatory marker (sTNF-α) (P = 0.014) and tubular injury marker (uNAG) (P = 0.001) that displayed a significant association with severity of sepsis (0.001, 0.035) and organ dysfunction (0.012, 0.0001) respectively. In critically ill patients with sepsis induced AKI, serum TNF-α and uNAG measured at admission can predict severity of sepsis and AKI (defined by REFILE) occurrence along with pre-existing CKD and DM. However, TNF-238 yielded additional prognostic information on ICU mortality irrelevant to AKI in septic patients.

Testosterone, obesity, and waist circumference as determinants of metabolic syndrome in Saudi women.

BACKGROUND: High serum total testosterone is associated with metabolic syndrome (MS). This study aimed to identify possible alterations in total testosterone and their relationship with plasma glucose, blood pressure, and serum lipid profile. METHODS: One hundred forty-two female subjects were selected to participate in this study, and they were recruited by consultant physicians from the Clinic and Medical Out-Patient, King Abdulaziz Hospital, Kingdom of Saudi Arabia. The anthropometric characteristics were obtained from questionnaires by using standard methods. Blood samples were obtained for the determination of glucose, triglycerides, total cholesterol, low-density lipoprotein, and high-density lipoprotein by using enzymatic methods. Total testosterone was determined by enzyme-linked immunosorbent assay for the quantitative measurement of testosterone in human serum. RESULTS: Significantly higher concentrations of total testosterone, low-density lipoprotein, and glucose, but lower concentrations of high-density lipoprotein, were observed in subjects with MS compared with women without MS (P<0.05). CONCLUSION: This study suggests that high levels of total testosterone and disturbance in lipid profile were associated with MS in Saudi women.

Wild-Type Isocitrate Dehydrogenase 1 Over-Expression is Related to Cancer Stem Cells Survival in Lung Adenocarcinoma.

Altered metabolism is one of the characteristics of cancer cells. We evaluated the expression of wild-type Isocitrate Dehydrogenase 1 (IDH1) and the cancer stem cells (CSCs) marker CD44 by real-time PCR and levels of reduced form of glutathione in lung biopsies of 32 adenocarcinoma patients and 18 control subjects. We found that IDH1 and CD44 expression and the levels of reduced form of glutathione were significantly higher in lung adenocarcinoma patients. IDH1 was positively correlated with CD44 and reduced form of glutathione. In conclusion, wild-type IDH1 is over-expressed in lung adenocarcinoma which probably promoted tumor progression via increasing CSCs survival.

The effect of obesity and components of metabolic syndrome on leptin levels in Saudi women.

BACKGROUND: Leptin levels are reported to be increased with excessive body fat and is a potential determinant of obesity and its complications. Our Objective is to evaluate the relationship between leptin levels and BMI, waist circumference and metabolic syndrome components in normal and obese females classified according to their BMI. SUBJECTS AND METHODS: A total of 136 female subjects aged between 20 and 60 years were recruited for the current study. Anthropometric measures included body mass index and waist circumference. The blood samples were used for estimation of plasma fasting blood glucose and serum was used for estimation of triglycerides, total cholesterol, low and high density lipoproteins, and total leptin. RESULTS: Correlation between glucose and lipids profile with waist circumference among the whole study group (obese and non-obese) is reflecting that a strong positive correlation between BMI and blood glucose, serum TGs, cholesterol and LDL, a negative correlation was reported between BMI and serum HDL. Mean of leptin concentrations in two groups were found to be 5.77 ng/ml (±1.00) in non-obese and 28.89 ng/ml (±4.91) in the obese with metabolic syndrome. Leptin had a positive correlations with triglycerides (r = 0.84, p < 0.001), total cholesterol (r = 0.77, p < 0.001), LDL (r = 0.83, p < 0.001), waist circumference (r = 0.86, p < 0.001) and BMI (r = 0.72, p < 0.001) in the test group. a negative correlation was reported between BMI and serum HDL (r = -0.48, p < 0.001). CONCLUSION: Leptin levels were high in Saudi women with high BMI and waist circumference. There was a significant correlation between leptin levels and Obesity.

Exploitation of Gene Expression and Cancer Biomarkers in Paving the Path to Era of Personalized Medicine.

Cancer therapy agents have been used extensively as cytotoxic drugs against tissue or organ of a specific type of cancer. With the better understanding of molecular mechanisms underlying carcinogenesis and cellular events during cancer progression and metastasis, it is now possible to use targeted therapy for these molecular events. Targeted therapy is able to identify cancer patients with dissimilar genetic defects at cellular level for the same cancer type and consequently requires individualized approach for treatment. Cancer therapy begins to shift steadily from the traditional approach of "one regimen for all patients" to a more individualized approach, through which each patient will be treated specifically according to their specific genetic defects. Personalized medicine accordingly requires identification of indicators or markers that guide in the decision making of such therapy to the chosen patients for more effective therapy. Cancer biomarkers are frequently used in clinical practice for diagnosis and prognosis, as well as identification of responsive patients and prediction of treatment response of cancer patient. The rapid breakthrough and development of microarray and sequencing technologies is probably the main tool for paving the way toward "individualized biomarker-driven cancer therapy" or "personalized medicine". In this review, we aim to provide an updated knowledge and overview of the current landscape of cancer biomarkers and their role in personalized medicine, emphasizing the impact of genomics on the implementation of new potential targeted therapies and development of novel cancer biomarkers in improving the outcome of cancer therapy.

The Schizosaccharomyces pombe cdt2(+) gene, a target of G1-S phase-specific transcription factor complex DSC1, is required for mitotic and premeiotic DNA replication.

We have defined five sev genes by genetic analysis of Schizosaccharomyces pombe mutants, which are defective in both proliferation and sporulation. sev1(+)/cdt2(+) was transcribed during the G1-S phase of the mitotic cell cycle, as well as during the premeiotic S phase. The mitotic expression of cdt2(+) was regulated by the MCB-DSC1 system. A mutant of a component of DSC1 affected cdt2(+) expression in vivo, and a cdt2(+) promoter fragment containing MCB motifs bound DSC1 in vitro. Cdt2 protein also accumulated in S phase and localized to the nucleus. cdt2 null mutants grew slowly at 30 degrees and were unable to grow at 19 degrees. These cdt2 mutants were also medially sensitive to hydroxyurea, camptothecin, and 4-nitroquinoline-1-oxide and were synthetically lethal in combination with DNA replication checkpoint mutations. Flow cytometry analysis and pulsed-field gel electrophoresis revealed that S-phase progression was severely retarded in cdt2 mutants, especially at low temperatures. Under sporulation conditions, premeiotic DNA replication was impaired with meiosis I blocked. Furthermore, overexpression of suc22(+), a ribonucleotide reductase gene, fully complemented the sporulation defect of cdt2 mutants and alleviated their growth defect at 19 degrees. These observations suggest that cdt2(+) plays an important role in DNA replication in both the mitotic and the meiotic life cycles of fission yeast.