Targeting the epigenome in malignant melanoma: Facts, challenges and therapeutic promises.

Malignant melanoma is the most lethal type of skin cancer with high rates of mortality. Although current treatment options provide a short-clinical benefit, acquired-drug resistance highlights the low 5-year survival rate among patients with advanced stage of the disease. In parallel, the involvement of an aberrant epigenetic landscape, (e.g., alterations in DNA methylation patterns, histone modifications marks and expression of non-coding RNAs), in addition to the genetic background, has been also associated with the onset and progression of melanoma. In this review article, we report on current therapeutic options in melanoma treatment with a focus on distinct epigenetic alterations and how their reversal, by specific drug compounds, can restore a normal phenotype. In particular, we concentrate on how single and/or combinatorial therapeutic approaches have utilized epigenetic drug compounds in being effective against malignant melanoma. Finally, the role of deregulated epigenetic mechanisms in promoting drug resistance to targeted therapies and immune checkpoint inhibitors is presented leading to the development of newly synthesized and/or improved drug compounds capable of targeting the epigenome of malignant melanoma.

Hyperthermia induces therapeutic effectiveness and potentiates adjuvant therapy with non-targeted and targeted drugs in an in vitro model of human malignant melanoma.

In the present study, we have aimed to characterize the intrinsic, extrinsic and ER-mediated apoptotic induction by hyperthermia in an in vitro model of human malignant melanoma and furthermore, to evaluate its therapeutic effectiveness in an adjuvant therapeutic setting characterized by combinational treatments with non-targeted (Dacarbazine & Temozolomide) and targeted (Dabrafenib & Vemurafenib) drugs. Overall, our data showed that both low (43 °C) and high (45 °C) hyperthermic exposures were capable of inducing cell death by activating all apoptotic pathways but in a rather distinct manner. More specifically, low hyperthermia induced extrinsic and intrinsic apoptotic pathways both of which activated caspase 6 only as opposed to high hyperthermia which was mediated by the combined effects of caspases 3, 7 and 6. Furthermore, significant involvement of the ER was evident (under both hyperthermic conditions) suggesting its role in regulating apoptosis via activation of CHOP. Our data revealed that while low hyperthermia activated IRE-1 and ATF6 only, high hyperthermia induced activation of PERK as well suggesting that ultimately these ER stress sensors can lead to the induction of CHOP via different pathways of transmitted signals. Finally, combinational treatment protocols revealed an effect of hyperthermia in potentiating the therapeutic effectiveness of non-targeted as well as targeted drugs utilized in the clinical setting. Overall, our findings support evidence into hyperthermia's therapeutic potential in treating human malignant melanoma by elucidating the underlying mechanisms of its complex apoptotic induction.

Potentially probiotic Lactobacillus strains with anti-proliferative activity induce cytokine/chemokine production and neutrophil recruitment in mice.

Lactobacillus pentosus B281 and Lactobacillus plantarum B282 are two Lactobacillus strains previously isolated from fermented table olives. Both strains were found to possess probiotic properties and displayed desirable technological characteristics for application as starters in novel functional food production. In the present study the anti-proliferative and immunostimulatory activities of the two strains were investigated. Firstly, we demonstrated that live L. pentosus B281 and L. plantarum B282 significantly inhibited the growth of human colon cancer cells (Caco-2) in a time- and dose-dependent manner. By employing the air pouch system in mice, we showed that administration of both strains led to a rapid and statistically significant infiltration of leukocytes in the air pouch exudates. The phenotypical characterisation of the recruited immune cells was performed by flow cytometry analysis. We demonstrated that the majority of the infiltrated leukocytes were neutrophils. Finally by using the Mouse Cytokine Array Panel A Detection Antibody cocktail, we showed that both strains induced the expression of granulocyte-colony stimulating factor, interleukin (IL)-1α, IL-1ß, IL-6, chemokine (C-X-C motif) ligand (CXCL)-1, chemokine (C-C motif) ligand (CCL)-3, CCL-4, and CXCL-2 and diminished the expression levels of soluble intercellular adhesion molecule, macrophage colony-stimulating factor and metallopeptidase inhibitor 1. Our results showed that both strains display anti-proliferative and immunostimulatory properties equal or even better in some cases than those of established and commonly used probiotic strains. These findings further support the probiotic character of the two strains.

Coexpression of IL-6 and TNF-α: prognostic significance on breast cancer outcome.

Presented study was conducted to investigate the prognostic significance of the coexpression of serum interleukin-6 (IL-6) and tumor necrosis factor-a (TNF-a) in breast cancer, by correlating their presence with clinicopathological characteristics indicative of tumor progression and the overall survival of breast cancer patients. One hundred twelve consecutive patients with primary breast cancer were prospectively included and evaluated. Serum concentrations of IL-6 and TNF-a were measured by quantitative sandwich enzyme immunoassay (ELISA). Median split was used to subdivide patients with low or high IL-6 and TNF-a levels. A positive association between the expression of the two cytokines was found. The coexpression of high IL-6 and TNF-α was independently associated with extended lymph node (>3) involvement (aOR, 7.8) and lymphovascular invasion (aOR, 14.1), increasing the prognostic significance of each cytokine separately; it also provided additional prognostic information regarding survival, defining a high-risk subgroup of patients with significantly shorter survival and higher risk of death compared to patients with both cytokines low (aHR, 4.45) and patients with only one cytokine high (aHR, 3.63). Our findings suggest that the coexpression of these two cytokines could be used clinically as a useful tumor marker for the extension and the outcome of the disease.

Laparoscopic cholecystectomy in acute cholecystitis: an analysis of the risk factors.

BACKGROUND AND AIM: Laparoscopic cholecystectomy (LC) is increasingly being used as the initial surgical approach in patients with acute cholecystitis (AC). We describe our experience with LC in the treatment of AC. MATERIALS AND METHODS: In this study 2 412 patients underwent LC, in 315 cases for AC. The diagnosis was based on clinical, laboratory and intra-operative findings. Rates of conversion, complications, length of hospital stay, operating times, and factors associated with conversion or morbidity were analysed. RESULTS: Conversion to open cholecystectomy was necessary in 60 patients (19.04%) with AC. Factors associated with conversion were age >65 years, male gender, presence of empyema, previous abdominal surgery, and fever (temperature >37.5oC). There were no deaths, and the complication rate was 6.4%. The only risk factor for morbidity was a bilirubin level of >20.52 µmol/l. The operating time and hospital stay were significantly longer in AC than in elective cases. CONCLUSIONS: LC for AC is technically demanding but safe and effective. With patience, experience, careful dissection and identification of vital structures, the laparoscopic approach is safe in the majority of cases.

Comparison of angiogenic activity after urethral reconstruction using free grafts and pedicle flap: an experimental study.

PURPOSE: An experimental study was undertaken in order to estimate the angiogenic activity in different free grafts and pedicle flap in urethral reconstruction in an animal model. METHODS: Twenty-eight white New Zealand rabbits were randomly divided into five groups (O, A, B, C and D). A ventral urethral defect was created in all groups. In the group O, (n = 4), a simple closure of the defect was performed. Free penile skin graft (group A, n = 6), buccal mucosal graft (group B, n = 6), bladder mucosal graft (group C, n = 6), and pedicle penile skin graft (group D, n = 6) were used to bridge the urethral defect as an onlay patch. The animals were euthanized on the 21st postoperative day. The angiogenic activity was assessed with immunohistochemistry, using the anti-CD31 MoAb and the alkaline phosphatase antialkaline phosphatase procedure. The native vascularity of penile skin as well as buccal and bladder mucosa was assessed in rabbits from group O (n = 3). Statistical analysis was performed using one-way ANOVA. RESULTS: The angiogenesis seen with a magnification of x 200 in groups O, A, B, C, and D was 34.1 +/- 4.1 (mean +/- SD), 61.7 +/- 6.4, 94.3 +/- 6.4, 91.5 +/- 7.2, and 30.8 +/- 5.2 vessels per optical field, respectively. There were statistically significant differences (p < 0.001) between group O and groups A, B, C and between group A and groups B, C, D, but not (p > 0.5) between groups B and C and groups O and D. The native vascularity of penile skin, buccal mucosa and bladder mucosa was 23.3 +/- 3.0, 24.6 +/- 3.7 and 17.0 +/- 2.6 vessels per optical field, respectively. CONCLUSION: Buccal and bladder mucosal grafts exhibit a higher angiogenic activity than free and pedicle penile skin flap when transplanted in urethral defects. As the buccal mucosal graft showed the higher angiogenic activity and its harvesting is easier than bladder mucosa, we propose that in urethral reconstruction surgery the use of this graft might offer more reliable results.

Risk factors for conversion of laparoscopic cholecystectomy to open cholecystectomy.

BACKGROUND: Conversion to open cholecystectomy is still required in some patients. The aim of this study was to evaluate preoperative factors associated with conversion to open cholecystectomy in elective cholecystectomy and acute cholecystitis. METHODS: The records of 1,804 patients who underwent cholecystectomy from May 1992 to January 2004 were reviewed retrospectively. The demographics and preoperative data of patients who required conversion to laparotomy were compared to those with successful laparoscopic cholecystectomy. RESULTS: Conversion to open cholecystectomy was needed in 94 patients (5.2%),of which 44 (2.8%) had no inflammation and 50 (18.4%) had acute inflammation of the gallbladder. Male gender, age older than 60 years, previous upper abdominal surgery, diabetes, and severity of inflammation were all significantly correlated with an increased conversion rate to laparotomy. Also, the conversion from laparoscopic to open cholecystectomy in acute cholecystitis patients was associated with greater white blood cell count, fever, elevated total bilirubin, aspartate transaminase, and alanine transaminase levels, and the various types of inflammation. CONCLUSIONS: None of these risk factors were contraindications to laparoscopic cholecystectomy. This may help predict the difficulty of the procedure and permit the surgeon to better inform patients about the risk of conversion from laparoscopic to open cholecystectomy.

Laparoscopic cholecystectomy in patients with previous upper or lower abdominal surgery.

BACKGROUND: Previous abdominal surgery has been reported as a relative contraindication to laparoscopic cholecystectomy. This study specifically examined the effect of previous intraabdominal surgery on the feasibility and safety of laparoscopic cholecystectomy. METHODS: Data from 1,638 consecutive patients who underwent laparoscopic cholecystectomy were reviewed and analyzed for open conversion rates, operative times, intra- and postoperative complications, and hospital stay. RESULTS: Of the 1,638 study patients 473 (28.9%) had undergone previous abdominal surgery: 58 upper and 415 lower abdominal operations. The 262 patients who had undergone only a previous appendectomy were excluded from further analysis. Adhesions were found in 70.7%, 58.8% and 2.1% of patients respectively, who had previous upper, lower or no previous abdominal surgery with adhesiolysis required, respectively, in 78%, 30% and 0% of these cases. There were no complications directly attributable to adhesiolysis. Patients with previous upper abdominal surgery had a longer operating time (66.4 +/- 34.2 min), a higher open conversion rate (19%), a higher incidence of postoperative wound infection (5.2%), and a longer postoperative stay (3.4 +/- 2.1 days) than those who had undergone previous lower abdominal surgery (50.8 +/- 24 min, 3.3%, 0.7%, and 2.6 +/- 1.4 days, respectively) and those without prior abdominal surgery (47.4 +/- 25.6 min, 5.4%, 1.2%, and 2.8 +/- 1.9 days, respectively). CONCLUSIONS: Previous abdominal operations, even in the upper abdomen, are not a contraindication to safe laparoscopic cholecystectomy. However, previous upper abdominal surgery is associated with an increased need for adhesiolysis, a higher open conversion rate, a prolonged operating time, an increased incidence of postoperative wound infection, and a longer postoperative stay.

Laparoscopic cholecystectomy in a patient with situs inversus totalis and previous abdominal surgery.

Situs inversus totalis is a rare congenital defect that can present difficulties during laparoscopic surgery due to the mirror-image anatomy. We report a patient with symptomatic cholelithiasis and previous abdominal surgery in whom a chest X-ray revealed a right-sided heart, whereas abdominal ultrasound revealed that his gallbladder was located in the left hypochondrium. At surgery, the surgeon and the camera assistant were standing on the right-hand side of the patient, and the first assistant was standing on the left. The camera was introduced through an umbilical incision, and laparoscopy confirmed the situs inversus. The other 10-mm trocar was placed in the midline left of the falciform ligament and two 5-mm trocars were placed in the left subcostal midclavicular line and anterior axillary line, respectively. After dissection of multiple adhesions caused by previous abdominal surgery, a standard laparoscopic cholecystectomy was performed successfully. This report suggests that situs inversus is not a contraindication for laparoscopic surgery. However, the procedure is more difficult and potentially hazardous due to the mirror-image anatomy (particularly the transposition of biliary ducts) causing difficulties in orientation, so that extreme care is required to avoid iatrogenic injuries. Despite these factors, laparoscopic cholecystectomy can be performed safely in patients with situs inversus totalis.

Intraperitoneal abscess after an undetected spilled stone.

Gallbladder perforation with loss of calculi in the abdomen is frequent during laparoscopic cholecystectomy and can cause serious late complications. We report on a 65-year-old woman who underwent laparoscopic cholecystectomy for gallbladder empyema, during which a stone spilled into the peritoneal cavity. The spilled gallstone was not noticed during the initial operation. Three months later, she reported left upper quadrant pain of recent onset without associated symptoms such as fever, nausea, or weight loss. On examination, a palpable 2-cm tender subcutaneous mass was found. Abdominal ultrasound demonstrated an incarcerated hernia, and computed tomography (CT) scan showed an intraperitoneal abscess located in the back of the anterior abdominal wall in the left upper quadrant, which contained a recalcification figure. The patient was brought to surgery, at which time an incision was made over the mass. A chronic abscess in the back of the abdominal wall, also spreading into the subfascial space, was drained, and purulent material was obtained with a large stone, 2.8 cm in diameter, which had become lodged in the rectus abdominis after an undetected stone spillage during laparoscopic cholecystectomy. The patient continued receiving antibiotic treatment for 7 days, recovered well, and was discharged 7 days after drainage of the abscess.