Notch1 inactivation promotes invasion and metastasis of nasopharyngeal carcinoma cells partly through Slug activation.

Nasopharyngeal carcinoma (NPC) is a rare form of the head and neck cancer of the epithelial lining of the nasopharynx and exhibits the highest metastatic rate among head and neck cancers. Underlying mechanisms of metastasis remain largely unknown. Here, we explored whether Notch1 affects the invasion and metastasis of NPC cells. In vitro migration and invasion capacities were evaluated after the knockdown of Notch1 expression in NPC cells. To investigate the role of Notch1 in in vivo metastasis, we examined the metastatic ability to the lungs following administration of cancer cells via mouse tail vein. The expression of epithelial-mesenchymal transition (EMT) markers associated with Notch1-mediated metastasis was investigated, and their roles in metastasis and relationship with Notch1 expression were investigated. Suppression of Notch1 expression increased the ability of NPC cells to invade Matrigel in vitro. Knockdown of Notch1 expression in NPC cells resulted in extensive lung metastasis in a mouse model and increased the mRNA expression of Slug in NPC cells. Slug-specific RNA interference resulted in the loss of the metastatic and invasion capacities in Notch1-suppressed NPC cells. These findings show that Notch1 has a significant suppressive role in the regulation of metastasis in NPCs, suggestive of its prudent use in clinical trials.

Retrospective analysis of the effect of CAPOX and mFOLFOX6 dose intensity on survival in colorectal patients in the adjuvant setting.

BACKGROUND: Despite lack of a true comparative study, the folfox (5-fluorouracil-leucovorin-oxaliplatin) and capox (capecitabine-oxaliplatin) regimens are believed to be similar in their efficacy and tolerability in the treatment of stage iii colorectal cancer. However, that belief has been disputed, because real-life data suggest that the capox regimen is more toxic, leading to more frequent reductions in the delivered dose intensity-thus raising questions about the effect of dose intensity on clinical outcomes. METHODS: A retrospective data review for two Canadian institutions, the Segal Cancer Centre and the Tom Baker Cancer Centre, considered patients diagnosed with stage iii colorectal cancer during 2006-2013. Primary endpoints were dose intensity and toxicity, with a secondary endpoint of disease-free survival. RESULTS: The study enrolled 180 eligible patients (80 at the Segal Cancer Centre, 100 at the Tom Baker Cancer Centre). Of those 180 patients, 75 received capox, and 105 received mfolfox6. In the capox group, a significant dose reduction was identified for capecitabine compared with 5-fluorouracil in mfolfox6 group (p = 0.0014). Similarly, a significant dose reduction was observed for oxaliplatin in mfolfox6 compared with oxaliplatin in capox (p = 0.0001). Compared with the patients receiving capox, those receiving mfolfox6 were twice as likely to experience a treatment delay of more than 1 cycle-length (p = 0.03855). Toxicity was more frequent in patients receiving mfolfox6 (nausea: 30% vs. 18%; diarrhea: 47% vs. 24%; peripheral sensory neuropathy: 32% vs. 3%). At a median follow-up of 40 months, preliminary data showed no difference in disease-free survival (p = 0.598). Pooled data from both institutions were also separately analyzed, and no significant differences were found. CONCLUSIONS: Our results support the use of capox despite a lack of head-to-head randomized trial data.

Progression pattern and adverse events with bevacizumab in glioblastoma.

BACKGROUND: The use of bevacizumab in the management of glioblastoma multiforme (gbm) remains controversial. In Canada, bevacizumab is approved for the treatment of recurrent gbm. We describe a pattern of progression across treatment lines in gbm. METHODS: During 2008-2014, 64 patients diagnosed with gbm were treated with bevacizumab at McGill University hospitals. Of those patients, 30 (46.9%) received bevacizumab in the first line (B1L), and 34 (53.1%) received it in the second line and beyond (B2L+). The average length of treatment with bevacizumab was 24.4 weeks (range: 0-232.7 weeks). The patterns of progression were categorized as local, distant, diffuse, multifocal, or multi-pattern. RESULTS: Local progression was seen in 46.7% of B1L patients and 26.5% of B2L+ patients, distant in 3.3% and 2.9%, diffuse in 20% and 47%, multifocal in 10% and 8.8%, and multi-pattern in 3.3% and 11.8%. No differences between the groups were observed for the distant (p = 0.3) or diffuse (p = 0.4) patterns. Grades 3 and 4 adverse events in the B1L and B2L+ groups were fatigue (33.3% vs. 17.6% respectively), hypertension (26.7% vs. 5.9%), thrombocytopenia (26.7% vs. 11.8%), neutropenia (26.7% vs. 11.8%), anemia (23.3% vs. 11.8%), leucopenia (20% vs. 8.8%), deep vein thrombosis (23.3% vs. 5.9%), seizure (16.7% vs. 8.8%), brain hemorrhage (6.7% vs. <1%), and delayed wound healing (6.7% vs. 2.9%). More total grades 3 and 4 adverse events occurred in the B1L group (p = 0.000519). CONCLUSIONS: In our cohort, patterns of progression were not different in B1L and B2L+ patients. Moreover, both groups experienced similar adverse events, although more grades 3 and 4 events occurred in the B1L group, implying that severe adverse events in B1L patients could negatively affect survival outcomes.

Quantifying treatment delays in adolescents and young adults with cancer at McGill University.

BACKGROUND: Since the end of the 1980s, the magnitude of survival prolongation or mortality reduction has not been the same for adolescents and young adults (ayas) with cancer as for their older and younger counterparts. Precise reasons for those observations are unknown, but the differences have been attributed in part to delays in diagnosis and treatment. In 2003 at the Jewish General Hospital, we developed the first Canadian multidisciplinary aya oncology clinic to better serve this unique patient population. The aim of the present study was to develop an approach to quantify diagnosis delays in our aya patients and to study survival in relation to the observed delay. METHODS: In a retrospective chart review, we collected information about delays, treatment efficacy, and obstacles to treatment for patients seen at our aya clinic. RESULTS: From symptom onset, median time to first health care contact was longer for girls and young women (62 days) than for boys and young men (6 days). Median time from symptom onset to treatment was 173 days; time from first health care contact to diagnosis was the largest contributor to that duration. Delays in diagnosis were shorter for patients who initially presented to the emergency room, but compared with patients whose first health contact was of another type, patients presenting to the emergency room were 3 times more likely to die from their disease. CONCLUSIONS: Delays in diagnosis are frequently reported in ayas with cancer, but the duration of the delay was unrelated to survival in our sample. Application of this approach to larger prospective samples is warranted to better understand the relation between treatment delay and survival in ayas-and in other cancer patient groups.

SOX2 regulates self-renewal and tumorigenicity of stem-like cells of head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous cell carcinomas (HNSCCs) display cellular heterogeneity and contain cancer stem cells (CSCs). Sex-determining region Y [SRY]-box (SOX)2 is an important regulator of embryonic stem cell fate and is aberrantly expressed in several types of human tumours. Nonetheless, the role of SOX2 in HNSCC remains unclear. METHODS: We created cells ectopically expressing SOX2 from previously established HNSCC cells and examined the cell proliferation, self-renewal capacity, and chemoresistance of these cells compared with control cells. In addition, we knocked down SOX2 in primary spheres obtained from HNSCC tumour tissue and assessed the attenuation of stemness-associated traits in these cells in vitro and in vivo. Furthermore, we examined the clinical relevance of SOX2 expression in HNSCC patients. RESULTS: SOX2 is aberrantly expressed in primary tissue of HNSCC patients but not in healthy tissue. SOX2 expression correlated with tumour recurrence and poor prognosis of HNSCC patients. Ectopic expression of SOX2 induced cell proliferation via cyclin B1 expression and stemness-associated features, such as self-renewal and chemoresistance. In addition, a knockdown of SOX2 in HNSCC CSCs attenuated their self-renewal capacity, chemoresistance (through ABCG2 suppression), invasion capacity (via snail downregulation), and in vivo tumorigenicity. CONCLUSIONS: These results suggest that SOX2 may have important roles in the 'stemness' and progression of HNSCC. Targeting SOX2-positive tumour cells (CSCs) could be a new therapeutic strategy in HNSCCs.

Adjuvant therapy for stages II and III colon cancer: risk stratification, treatment duration, and future directions.

Background: To date, the role of adjuvant systemic therapy in stages ii and iii colon cancer remains a topic of interest and debate. The objective of the present review was to assess the most recent data, specifically addressing methods of risk stratification, duration of therapy, and future directions. Methods: PubMed and medline were searched for literature pertinent to adjuvant chemotherapy in either stage ii or stage iii colorectal cancer. Summary: Locoregional disease, histopathology, age, laterality, and a number of other biologic and molecular markers appear to have a role in disease risk stratification. The duration of adjuvant therapy for stage iii disease can vary based on risk factors, but use of adjuvant therapy and duration of therapy in stage ii disease remain controversial. Future directions should include genomic assays and improved study design to provide concrete evidence about the duration of adjuvant folfox or capox and about other types of chemotherapy and immunotherapy.

Base of tongue cancer-is it tongue cancer located at the base of the tongue, or is it a type of lingual tonsil cancer? The perspective from a genomic analysis.

The aim of this study was to determine whether base of tongue (BOT) cancer is tongue cancer located at the base of the tongue or lingual tonsil cancer originating from tonsil tissue. This was a retrospective study using data from The Cancer Genome Atlas (TCGA). The genomic patterns of three primary cancers (BOT, oral tongue, and tonsil) were compared to determine their similarities and differences. Gene expression data (n=193; 26 BOT, 125 oral tongue, and 42 tonsil cases), copy number alteration data (n=142; 19 BOT, 96 oral tongue, and 27 tonsil cases), and somatic mutation data (n=187; 25 BOT, 122 oral tongue, and 40 tonsil cases) were analyzed using the t-test, heatmap analysis, and OncoPrint, respectively. Clinical information for the three tumour groups was included in the analyses. When using multiplatform analysis, BOT cancer showed nearly the same genomic pattern as tonsil cancer, but not oral tongue cancer. The χ2 test and survival analysis revealed that BOT cancer had the same clinical and survival patterns as tonsil cancer. In conclusion, BOT cancer showed a genomic pattern similar to that of tonsil cancer, but different to that of oral tongue cancer. Further prospective studies are warranted before the results of this study can be applied in a clinical setting.

Oncological and functional results after the surgical treatment of parotid cancer.

The objective of this study was to analyze the oncological and functional outcomes after the surgical treatment of parotid cancer. We reviewed 80 primary parotid carcinomas retrospectively. A superficial parotidectomy was performed in 10 patients; 27 patients underwent total parotidectomy and 43 patients underwent radical parotidectomy. A facial-facial nerve anastomosis was chosen for the facial nerve reconstruction in eight patients, while an interpositional graft was selected in 24 patients. The overall N-positive rate of pathology was 21.3%. The rate of occult metastasis was 8.1%. High-grade carcinoma and lymphovascular emboli were independent factors for nodal metastasis. The 5-year disease-free survival and overall survival rates were 79.7% and 78.8%, respectively. Preoperative facial nerve palsy and extraparenchymal invasion were the independent factors associated with poor disease-free survival. Of the 41 patients in the facial nerve preservation group, 13 (31.7%) had transient facial nerve paresis. In the facial nerve sacrifice group of 39 cases, (sub)total recovery (House-Brackmann grade I/II) occurred in 14 (35.9%), partial recovery (House-Brackmann grade III/IV) in 13 (33.3%), and no recovery (House-Brackmann grade V) in 12 (30.8%). Facial nerve palsy upon presentation and extraparenchymal invasion indicate a grave prognosis. Facial nerve function after proper reconstruction is tolerable.

Oct4 is a critical regulator of stemness in head and neck squamous carcinoma cells.

Cancer stem cells (CSCs) have been suggested as responsible for the initiation and progression of cancers. Octamer-binding transcription factor 4 (Oct4) is an important regulator of embryonic stem cell fate. Here, we investigated whether Oct4 regulates stemness of head and neck squamous carcinoma (HNSC) CSCs. Our study showed that ectopic expression of Oct4 promotes tumor growth through cyclin E activation, increases chemoresistance through ABCC6 expression and enhances tumor invasion through slug expression. Also, Oct4 dedifferentiates differentiated HNSC cells to CSC-like cells. Furthermore, Oct4(high) HNSC CSCs have more stem cell-like traits compared with Oct4(low) cells, such as self-renewal, stem cell markers' expression, chemoresistance, invasion capacity and xenograft tumorigeneity in vitro and in vivo. In addition, knockdown of Oct4 led to markedly lower HNSC CSC stemness. Finally, there was a significant correlation between Oct4 expression and survival of 119 HNSC patients. Collectively, these data suggest that Oct4 may be a critical regulator of HNSC CSCs and its targeting may be potentially valuable in the treatment of HNSC CSCs.

Antitumor activity and nephrotoxicity of a novel platinum complex, [1,3-bis(diphenylphosphino)propane](trans-1-dach)platinum(I I) dinitrate.

We have developed a new class of platinum complex [Pt(trans-l-dach)(1,3-bis(phosphino)propane)] dinitrate (KHPC-001) with potent antitumor activity and low nephrotoxicity, confirmed in vitro and compared in vivo with cisplatin, KHPC-001 or cisplatin was intraperitoneally injected on days 1, 5, and 9 into P388-bearing mice and the antitumor effects were compared. In vitro cytotoxicity, Pt accumulation, and DNA cross-link index were measured in P388 and LLC-PK1 cells after treatment with KHPC-001 or cisplatin. Twenty mg/kg (below one-tenth of LD50) of KHPC-001 had stronger antitumor effects than 2 mg/kg (about one-fifth of LD50) of cisplatin and cured 2 out of 6 mice without any toxicity. While the cytotoxicity of KHPC-001 and cisplatin were similar on P388 mouse leukemia cells, this new compound was much less cytotoxic to a kidney-derived line, LLC-PK1. This lower toxicity on the kidney cells was based on its low accumulation, causing less DNA crosslinking. KHPC-001 is a unique third-generation platinum complex with potent antitumor activity and low nephrotoxicity.

Efficacy of the platinum analog [Pt(cis-dach)(DPPE)-2NO3] on histocultured human patient bladder tumors and cancer cell lines.

Cisplatinum is currently used as a front line agent in many important tumors, but its dose-limiting nephrotoxicity prevents potential efficacy. There is therefore great interest in developing new platinum agents that have less toxicity. We have synthesized new platinum analogues containing DACH as a carrier ligand and DPPE as a leaving group. Previously we showed that these new platinum complexes have much less nephrotoxicity than cisplatinum. In the present study, the efficacy of one new platinum complex was evaluated with human patient bladder tumor specimens in three-dimensional histoculture as well as with monolayer cultures of cancer cell lines. The efficacy end points used were glucose consumption and thymidine incorporation on the histocultured specimens and MTT reduction on monolayer cell cultures. Our results showed that the new platinum complex was more effective at high concentration (10(-3) M) but less effective at low concentration (10(-4) M) compared to cisplatinum on histocultured bladder tumor specimens. The compound demonstrated higher efficacy than cisplatinum on P-388, and L-1210 leukemic cell lines. The new analog demonstrated similar efficacy to cisplatinum on the MKN-45 human stomach cancer cell line. The PC-14 human lung cancer cell line, MH1C1 rat hepatoma cell line, NIH-OV3, SKOV-3 ovarian cancer cell lines were as sensitive to the new analog as to cisplatinum at high concentrations of the new platinum analogue. The cisplatinum-resistant M-14 melanoma cell line was not sensitive to either the new analog or cisplatinum. Based on these results, this novel platinum compound appears to be a valuable lead compound with high efficacy and low nephrotoxicity.

New platinum complex compounds with reduced nephrotoxicity discovered in long-term histoculture of human renal cortical tissue.

Cisplatinum is often effective in cancer treatment, but potent nephrotoxicity limits its clinical use. We have synthesized six new platinum compounds with the goal of reducing toxicity while maintaining efficacy. We initially tested drugs at 5 x 10(-4)M with 48 hours exposure in monolayer cultures of primary rabbit proximal tubular cells and human renal cortical cells with the MTT endpoint to measure toxicity. Drug concentration of 10(-3)M, 10(-4)M and 10(-5)M with 72 hours exposure were used for human renal cortical tissues in 7 week sponge-gel-supported histoculture with toxicity measured by the glucose-consumption endpoint. From these studies, we determined that the new platinum drugs have lower nephrotoxicity than cisplatinum.

Antimetastatic activity of the new platinum analog [Pt(cis-dach) (DPPE).2NO3] in a metastatic model of human bladder cancer.

Surgical orthotopic implantation (SOI) of histologically intact human RT-4 bladder tumor tissue in nude mice resulted in local growth, invasion, regional extension and metastases as well as distant metastases to other organ sites and lymph nodes, thus mimicking the bladder cancer patient. This metastatic bladder tumor animal model was treated with two doses of new platinum analog ¿Pt(cis-dach)(DPPE).2NO3¿ for the evaluation of antimetastatic efficacy compared to two doses of cisplatinum. Unlike the untreated control group or the group treated with the low dose of cisplatinum, there were no metastases in either the high or low-dose platinum-analog-treated groups and the high-dose cisplatinum-treated group. The results obtained with this patient-like nude-mouse model of bladder cancer indicate that the new platinum analog appears to be a valuable lead compound with antimetastatic efficacy and clinical potential.

Efficacy of new platinum analog DPPE in an orthotopic nude mouse model of human colon cancer.

A surgical orthotopic implantation (S.O.I.) model of the human colon cancer cell line Co-3 in nude mice was treated with two doses of the new platinum analogs {Pt(cis-dach) (DPPE).2NO3} and {Pt(trans-dach)(DPPE).2NO3}. The analogs were evaluated for antimetastatic efficacy in comparison to two doses of cisplatinum. Unlike the untreated control group, there were no mesenteric lymph node metastases in the groups treated with the high or low doses of both forms of new DPPE platinum analogs as well as cisplatinum-treated group. However, much more body-weight loss occurred in the cisplatinum-treated group than the DPPE-treated groups. The results obtained with SOI animal model of colon cancer demonstrated both cis- and trans-forms of DPPE had as strong an inhibitory effect on metastasis as that of cisplatinum, but with much less toxicity. Thus the new platinum analogs appears to have promising clinical potential.

Discrepancy between preoperative MRI evaluation and intraoperative or postoperative pathological findings for the extent of local invasion in maxillary squamous cell carcinoma.

Preoperative radiological evaluation of the extent of local invasion in maxillary squamous cell carcinoma (SCC) is very important in planning curative surgery. The aim of this study was to examine the accuracy of preoperative radiological evaluation with magnetic resonance imaging (MRI) for the extent of local invasion in maxillary SCC. A retrospective study was conducted of 33 patients who underwent a maxillectomy for maxillary SCC. We compared the MRI findings for 18 structures around the maxillary sinus with intraoperative or postoperative pathological findings. Discrepancies were found between preoperative MRI findings and intraoperative or postoperative pathological findings for 22 patients (66.7%). Overall, the specificity, sensitivity, positive predictive value, and negative predictive value of MRI were 83.4%, 83.0%, 64.5%, and 90.4%, respectively. The receiver operating characteristic curve showed that MRI evaluation of the posterolateral structures including the pterygoid plate, pterygoid muscle, and infratemporal fossa had a lower area under the curve (0.614) and a significantly lower accuracy when compared with the other structures (P = 0.294, 95% confidence interval 0.405-0.822). In conclusion, as the accuracy of preoperative MRI evaluation of the posterolateral structures is low, careful evaluation of local extension to the posterolateral structures is needed when planning curative surgery for maxillary SCC.

Breast cancer sentinel lymph node mapping using near infrared guided indocyanine green and indocyanine green--human serum albumin in comparison with gamma emitting radioactive colloid tracer.

AIMS: Recently, a novel method of using near infrared (NIR) guided indocyanine green (ICG) and ICG conjugated with human serum albumin (ICG:HSA) for sentinel lymph node biopsy (SLNB) of breast cancer patients has shown true potential. The aim of this study was to compare the usefulness of NIR guided ICG and ICG:HSA against the gamma emitting radiocolloid (RC). METHODS: A group of 49 consecutive breast cancer patients underwent SLNB using RC. From this group, the first 28 patients were compared against ICG, while the next 21 patients were compared against ICG:HSA. The number of patients with visible fluorescent path was recorded. Furthermore, the number of SLNs detected by fluorophores percutaneously and total number of intraoperative SLNs detected by fluorophores and/or RC was noted. RESULTS: NIR guided real time lymphatic flow was observed in 47/49 patients (96%). In all cases except one, SLNs detected by the RC tracer were also detected by their respective fluorophore. Additionally, ICG detected 10 additional SLNs in 8 patients, while 3 additional SLNs were detected by ICG:HSA in 3 patients. Statistical analysis revealed no difference between the number of SLNs detected between ICG versus ICG:HSA and RC versus ICG:HSA. However, a significant statistical difference was observed between RC and ICG (p=0.0117), as well as between the combined NIR guided and RC method (p=0.0033). CONCLUSIONS: In conclusion, the use of either ICG or ICG:HSA with RC to obtain SLNB seems to be an effective alternative. Compared to RC alone, the use of ICG:HSA, more so than ICG alone, may provide additional benefits.

Column-switching high-performance liquid chromatographic assay for determination of asiaticoside in rat plasma and bile with ultraviolet absorbance detection.

A column-switching high-performance liquid chromatography (HPLC) method is described for the determination of asiaticoside in rat plasma and bile using column-switching and ultraviolet (UV) absorbance detection. Plasma was simply deproteinated with acetonitrile prior to injection and bile was directly injected onto the HPLC system consisting of a clean-up column, a concentrating column, and an analytical column, which were connected with two six-port switching valves. Detection of asiaticoside was accurate and repeatable, with a limit of quantification of 0.125 microg/ml in plasma and 1 microg/ml in bile. The calibration curves were linear in a concentration range of 0.125-2.5 microg/ml and 1-20 microg/ml for asiaticoside in rat plasma and bile, respectively. This method has been successfully applied to determine the level of asiaticoside in rat plasma and bile samples from pharmacokinetics and biliary excretion studies.

The effects of chronic electrical stimulation on laryngeal muscle physiology and histochemistry.

The present study examined the effects of functional neuromuscular stimulation (FNS) on posterior cricoarytenoid (PCA) muscle physiology and histochemistry. In 4 canines, 10 cm of the recurrent laryngeal nerve was resected. A patch electrode array was implanted for PCA stimulation. FNS was applied to 2 canines for a period of 4 weeks with 2 additional animals serving as nonstimulated controls. Results indicated that FNS increased PCA muscle contractility over the period of intervention but had no effect on contraction speed. FNS also protected the muscle from atrophy by preventing muscle weight loss and type 2 fiber deterioration. Finally, it rescued muscle fibers from ensuing fibrosis.