Differential expression of MCM2 and SKP2 as biomarkers of therapy resistance in prostate cancer

Background

Prostate cancer (PCa) is the second most incident cancer and the sixth cause of cancer death among man worldwide. Patients diagnosed with advanced PCa are often treated with androgen deprivation therapy. Although tumors initially respond, they may progress to a lethal and drug-resistant form of PCa. Recent works from our team demonstrated that a promising anti-cancer agent is associated with reduced MCM2 and SKP2 expression in PCa cell lines. MCM2 and SKP2 play an important role in cell cycle progression with overexpression observed in several cancers with association with poor prognostic. Thus, to test its potential as predictive biomarker, MCM2 and SKP2 expression was evaluated in PCa tissues.

Methods

A total of 57 cases (25 resistant and 33 non-resistant) were used to explore MCM2 and SKP2 expression by immunohistochemistry. Percentage of positive tumor cells, intensity of immunostaining, and immunoexpression were blinded evaluated. Comparisons between therapy conditions and proteins expression were assessed by Chi square test (statistical significance considered when P < 0.05).

Results

MCM2 expression is associated to PCa patients’ therapy resistance, with significant differences found for percentage of positive tumor cells (P = 0.001) and immunostaining intensity (P = 0.002). SKP2 expression is also associated with resistance to therapy, with differences observed referred to immunostaining intensity (P = 0.001) and immunoexpression pattern (P = 0.02). Specifically, cytoplasmatic and nuclear expression was apparent in most cases that developed therapy-resistance, whereas responsive PCa patients showed only SKP2 cytoplasmatic expression.

Conclusions

In PCa patients, MCM2 and SKP2 expression is significantly associated with therapy resistance. SKP2 cellular localization is also indicative of patients’ resistance to treatment.

LDHA and CPT2 association with therapy resistance in prostate cancer

Background

The aerobic glycolysis as energy source in cancer confers a selective advantage for its proliferation and survival. Previous in vitro studies demonstrated that treatment with [C16Pyr][Amp], a potential anti-cancer drug in prostate, decreased the transcript levels of LDHA and CPT2, both involved in metabolic plasticity. In fact, LDHA and CPT2 were reported to be overexpressed in cancer, with association with poor prognosis and resistance to chemo- and radiotherapy. Since LDHA and CPT2 can be potential therapy resistance biomarkers, the aim of this work was to assess LDHA and CPT2 expression using PCa tissues.

Methods

LDHA and CPT2 expression was evaluated by immunohistochemistry in 57 PCa tissues, 24 from patients that developed resistance to hormonal therapy and 33 without therapy resistance. For both proteins, percentage of positive tumor cells, intensity of immunostaining, and immunoexpression pattern was determined by a blinded manner. Comparisons between therapy variables and protein expression were assessed using the Chi square test. P < 0.05 indicated a statistically significant difference.

Results

LDHA expression is significantly associated with therapy resistance (P < 0.001). Moreover, CPT2 pattern’s immunoexpression is also associated with therapy resistant (P < 0.001), being cytoplasmatic expression most frequent in patients that respond to therapy (41%), whereas both nuclear and cytoplasmatic expression is more prevalent in therapy-resistant cases (48%).

Conclusions

LDHA overexpression is significantly associated with therapy resistance in PCa cases, while CPT2 cell expression distribution might be a predictive marker.

LDHA is differential expressed in luminal A and luminal B breast cancer

Background

Breast cancer (BrCa) is the most incident cancer in women worldwide, with more than 2 200 000 new cases and 600 000 deaths in 2020. Concerning BrCa molecular signature, tumors expressing estrogen receptor (luminal A and B) normally respond to hormonal therapy, but some cases develop resistance. We recently showed that LDHA expression is reduced upon treatment with [C16Pyr][Amp], a new proposed anti-cancer drug. LDHA has been implicated in Warburg effect regulation and has been associated with BrCa patients’ worse outcome. So, the mail goal of this study was to evaluate LDHA expression in BrCa tissues and correlate it with several clinical and pathological parameters.

Methods

A total of 40 BrCa tissue samples were selected to assess LDHA expression by immunohistochemistry. Percentage of positive tumor cells, intensity of immunostaining, and immunoexpression pattern were blinded evaluated. Correlations between clinicopathological parameters and LDHA expression were assessed using the Chi square test (P < 0.05 was indicated of the statistically significance).

Results

Higher LDHA expression intensity significantly is associated with luminal B molecular subtype (P = 0.003). Conversely, no association is found between LDHA expression and tumor stage or therapy resistance.

Conclusions

The intensity of LDHA immunoexpression is related with luminal molecular subtype B. Since LDHA is associated with the production of lactate, leading to a greater energy obtaining by cancer cells, these cells may have an increased capacity for proliferation. In fact, this subtype was previously reported to express high Ki67 levels, a proliferative marker.

Fishes of the Taquari-Antas river basin (Patos Lagoon basin), southern Brazil

The aquatic habitats of the Taquari-Antas river basin (in the Patos Lagoon basin, southern Brazil) are under marked environmental transformation because of river damming for hydropower production. In order to provide an information baseline on the fish fauna of the Taquari-Antas basin, we provide a comprehensive survey of fish species based on primary and secondary data. We found 5,299 valid records of fish species in the basin, representing 119 species and 519 sampling sites. There are 13 non-native species, six of which are native to other Neotropical river basins. About 24% of the total native species are still lacking a taxonomic description at the species level. Three native long-distance migratory species were recorded (Leporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis), as well as two potential mid-distance migrators (Parapimelodus nigribarbis and Pimelodus pintado). Although there is only one officially endangered species in the basin (S. brasiliensis), restricted range species (21.7% of total species) should be considered in conservation efforts.

Prognostic factors for hepatocellular carcinoma recurrence: experience with 83 liver transplantation patients

INTRODUCTION

Orthotopic liver transplantation (OLT) is a rational therapeutic option for early-stage hepatocellular carcinoma (HCC) providing a potential cure and improving survival.

METHODS

This retrospective study of a longitudinal cohort used an electronic database collected prospectively from September 1997 to May 2010. The variables were gender, age (years), and alpha-fetoprotein (AFP) level (ng/mL). In explanted livers we observed: microvascular or macrovascular invasion, number of nodules and their largest size, Edmondson-Steiner histological differentiation, incidental tumor transarterial chemoembolization (TACE), Milan criteria, and previous down-staging.

RESULTS

Five of 83 (6.0%) subjects including 68 (82%) males with a mean time to diagnosis of 9 months experienced tumor relapses. Mean patient age at HCC recurrence was 55.3 years for male and 44.6 years for female subjects. Vascular invasion was detected in 17/83 (20.5%) subjects, namely 2% of macrovascular invasion, and 52.5% with expanded Milan criteria due to an increased number and size of nodules in the explanted livers. An incidental tumor was observed in 29.5% of cases. Preoperative TACE treatment was performed in 13 (15.6%) patients. None of the patients who had a HCC recurrence had undergone TACE. AFP level at the time of recurrence was around 1,900 ng/mL. The predictive factor for mortality was nodule size (P=.04; hazard ratio=0.0269; confidence interval [CI], 95% 0.0094-0.299).

CONCLUSION

Patients with relapses showed the worst survival and tumor size was a predictive factor for recurrence.

Portal vein thrombosis and liver transplantation: long term

Obstruction of the portal vein may be related to constriction by malignant tumors or thrombosis associated with liver disease. We herein have reported our experience with patients undergoing liver transplantation with portal vein thrombosis (PVT) whose diagnosis was made intraoperatively. From September 1991 to May 2009, we studied 27/419 (6.4%) patients with PVT who were evaluated according to the presence of esophagogastric varices, underlying disease, malignancy, and if there was previous surgery, review of medical records on data collected prospectively. We observed 24 (88.9%) patients with PVT grade 1, 2 (7.4%) with grade 2, and 1 (3.7%) with grade 3. The average age of the PVT patients was 47.5 years; the average model for End-Stage Liver Discase score was 18.3, and the predominant diagnosis, hepatitis C cirrhosis. Eighteen underwent a sclerotherapy/ligature. The sensitivity of ultrasound for grade 1 thrombosis was 39.1%; for grade 2, 50%; and for grade 3, 100%. Portal vein thrombectomy was performed in 24 patients. In other patients (grade 2), we performed an anastomosis of the donor portal vein to the recipient gastric vein or to a greater splanchnic collateral vein. In only 1 patient was the graft performed using the donor portal vein-donor iliac vein-recipient superior mesenteric vein. None of the patients displayed PVT in the immediate postoperative period. Actuarial survivals at the years 1, 3, and 5 were 85%, 74%, and 63%, respectively. We concluded that PVT cannot be considered to be a contraindication for liver transplantation.

Intraoperative massive transfusion decreases survival after liver transplantation

Patients undergoing liver transplantation often experience coagulopathy and massive intraoperative blood loss that can lead to morbidity and reduced survival. The aim of this study was to verify the survival rate and discover predictive factors for death among liver transplant patients who received massive intraoperative blood transfusions. This cohort study was based on prospective data collected retrospectively from January 2004 to July 2006. The 232 patients were distributed according to their blood requirements, (namely, more or less than 6 units), including red blood cell saver. The statistical analyses were performed using Student t test, Cox hazard regression, and the Kaplan-Meier method (log-rank test). The massively transfused cohort displayed higher Child-Pugh classifications (10.2 vs 9.6; P = .03); model for end-stage liver disease (MELD) scores (19 vs 17; P = .02); recipient weights (75.4 vs 71 kg; P = .03); as well as warm ischemia times (70.7 vs 56.4 minutes; P < .001) and surgery times (584.6 vs 503.4 minutes; P < .05). The proportional hazard (Cox) regression analysis showed that the risk of death increased 2.1% for each unit of donor sodium and 1.6% for each additional year of donors age over 50. The survival rates at 6, 12, 60, and 120 months for > or = 6 vs <6 U of blood transfusion of 63.8% vs 83.3%; 53.9% vs 76.3%; 40% vs 60%; 34.5% vs 49.2%. In conclusion, we observed that patients receiving over 6 red blood cell units intraoperatively displayed reduced survival. Predictive factors for this risk factor were high donor level of sodium and of age.

Perioperative methemoglobinemia

We report a case of a male patient who underwent splenectomy for idiopathic thrombocytopenic purpura. Oxygen saturation was 92% by pulse oximetry and cyanosis was apparent during the perioperative period. Methemoglobin (metHb) levels were 10.4%. After removal of the tracheal tube, intravenous methylene blue (1 mg/kg) was administered because of persistently low SpO2 levels (87%). During preanesthetic evaluation, the patient did not inform the anesthesiologist that he had been taking dapsone.

Gastrointestinal bleeding during liver transplantation--report of two cases

A few authors have reported, especially as intraoperative complications, gastrointestinal hemorrhage related to liver transplantation. The aim of this study was to show two cases of gastrointestinal hemorrhage, which occurred during surgery. The first patient was male, 46 years old, with viral hepatic cirrhosis. He had previously presented two episodes of digestive bleeding. Upper digestive endoscopy showed esophageal gastric varices. During the hepatectomy there was bleeding inside the nasogastric tube associated with severe hemodynamics instability without other sources of bleeding. Intraoperative endoscopy evidenced bleeding gastric varices. Gastrectomy was carried out and the varices were tied. The piggyback technique was used in the liver transplantation. The surgery was concluded without problems and in the following four and a half years his condition has evolved well. In the second case, the patient was aged 17, female, with autoimmune hepatic cirrhosis. She had previously presented one episode of digestive bleeding. Intraoperative endoscopy showed median esophageal varices. During the anesthetic induction she presented an episode of hematemesis. A Sengstaken-Blakemore balloon was introduced. The transplant was performed without further problems. Her case has been followed for 14 months in the outpatients' clinic with a good postoperative course. To sum up, gastrointestinal hemorrhage can be due to portal hypertension during the liver transplantation and must be treated quickly. In these cases the surgery must be ongoing.