Applying the QUARTZ Trial Results in Clinical Practice: Development of a Prognostic Model Predicting Poor Outcomes for Non-small Cell Lung Cancers with Brain Metastases

AIMS

The role of whole brain radiotherapy (WBRT) in patients with brain metastases from non-small cell lung cancers (NSCLC) has been questioned. However, no reliable criteria exist to identify patients who do not benefit from WBRT. The objective of the current study was to develop a prognostic model to identify such patients whose survival matches that of the Quality of Life after Treatment for Brain Metastases (QUARTZ) study.

MATERIALS AND METHODS

Outcome data of patients with NSCLC with brain metastases undergoing WBRT enrolled in a prospective observational study in a tertiary cancer centre were used to develop a prognostic model. Baseline clinico-radiological factors were used for development of the model. The model was internally validated and calibration accuracy was checked for prediction of 70 day mortality. The generated prognostic model was presented as a nomogram.

RESULTS

The median overall survival of 140 patients enrolled in the study was 166 days (95% confidence interval 108-242 days). The prognostic model identified gender, Karnofsky performance status and epidermal growth factor receptor activating mutation status as significant factors influencing overall survival. The model showed a modest discriminative ability with an optimism-corrected C-index of 0.64. However, model calibration error did reveal a moderate degree of calibration error. The high-risk subgroup identified by the model had a median overall survival of 67 days (95% confidence interval 56-101 days), which was similar to that observed in the QUARTZ trial.

CONCLUSION

This prognostic model derived from traditional clinico-radiological features had a modest ability to identify patients with poor prognosis who may not benefit from WBRT. However, the high-risk subgroup identified using this prognostic model had a survival similar to that observed for patients in the QUARTZ trial.

Abstract P5-03-06: Novel targets of breast cancer associated with inflammatory tumor microenvironment

Breast cancer affects one in eight women in the USA. Considerable progress in the identification of genetic lesions and their modulation has resulted in newer therapies making breast cancer a manageable disease. However, triple negative breast cancer is still difficult to treat and warrants a search for newer targets. To this end, we focused our attention towards the modulation of the breast cancer epithelium by other cell types such as the endothelial cells and the macrophages. The migratory macrophages and the estrogen sensitive migratory endothelial progenitor cells (EPCs) constitute the cellular milieu within the tumor microenvironment which continuously modulates breast cancer epithelium. We analyzed the interactions of the breast cancer cell lines (MCF-7 and MDA-MB-231) with the highly proliferative human umbilical cord derived CD133+/CD34+/VEGFR-2+ EPCs and M1 polarized macrophages (activated THP-1 cell line) in two separate in vitro studies. The readouts were cell proliferation, changes in epithelial to mesenchymal transition (EMT), and cellular differentiation. We observed morphological and cellular growth changes in the EPCs on treatment with conditioned medium (CM) generated from breast cancer cells, consistent with vasculogenesis and in vitro tubulogenesis. Both, MDA-MB-231 and MCF-7 CM, treatments resulted in enhanced EPCs proliferation and differentiation. However, the differentiation patterns were distinct, with MCF-7 CM increasing the number of cell clusters, whereas MDA-MB-231 CM increasing the number of adherent spindle shaped cells. The paracrine interaction was also assessed with M1 polarized macrophages. We observed decreased cell viability in MCF-7 and MDA-MB-231 cells following activated THP-1 CM and exosome treatments. Analysis of exosomes from activated THP-1 indicated an upregulation of 13 miRNAs compared to unactivated THP-1. The miRNA hsa-miR-146a-5p had the highest upregulation (44 fold increase). This specific miRNA has been observed in senescent cell and it inhibits cell proliferation, suggesting a possible mechanism for exosome-associated growth inhibition. The analysis of the paracrine interactive mediators between breast cancer cells, EPCs, and M1 polarized macrophages is likely to yield viable novel clinically translatable therapeutic targets.

Citation Format: Tiwari RK, Ben Rahoma G, Tuli N, Bednarczyk R, Maniyar RR, Chakraborty S, Singh S, Mittelman A, Geliebter J. Novel targets of breast cancer associated with inflammatory tumor microenvironment [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-03-06.

Highly efficient novel carbon monoxide gas sensor based on bismuth ferrite nanoparticles for environmental monitoring

Creation of novel functionality in materials is always fascinating for researchers/scientists.

Diagnostic Accuracy of Centrally Restricted Diffusion in the Differentiation of Treatment-Related Necrosis from Tumor Recurrence in High-Grade Gliomas

BACKGROUND AND PURPOSE

Centrally restricted diffusion has been demonstrated in recurrent high-grade gliomas treated with bevacizumab. Our purpose was to assess the accuracy of centrally restricted diffusion in the diagnosis of radiation necrosis in high-grade gliomas not treated with bevacizumab.

MATERIALS AND METHODS

In this prospective study, we enrolled patients with high-grade gliomas who developed a new ring-enhancing necrotic lesion and who underwent re-resection. The presence of a centrally restricted diffusion within the ring-enhancing lesion was assessed visually on diffusion trace images and by ADC measurements on 3T preoperative diffusion tensor examination. The percentage of tumor recurrence and radiation necrosis in each surgical specimen was defined histopathologically. The association between centrally restricted diffusion and radiation necrosis was assessed using the Fisher exact test. Differences in ADC and the ADC ratio between the groups were assessed via the Mann-Whitney U test, and receiver operating characteristic curve analysis was performed.

RESULTS

Seventeen patients had re-resected ring-enhancing lesions: 8 cases of radiation necrosis and 9 cases of tumor recurrence. There was significant association between centrally restricted diffusion by visual assessment and radiation necrosis (P = .015) with a sensitivity of 75% and a specificity of 88.9%, a positive predictive value 85.7%, and a negative predictive value of 80% for the diagnosis of radiation necrosis. There was a statistically significant difference in the ADC and ADC ratio between radiation necrosis and tumor recurrence (P = .027).

CONCLUSIONS

The presence of centrally restricted diffusion in a new ring-enhancing lesion might indicate radiation necrosis rather than tumor recurrence in high-grade gliomas previously treated with standard chemoradiation without bevacizumab.

Reprogramming of Molecular Switching Events in UPR Driven ER Stress: Scope for Development of Anticancer Therapeutics

The incitement of unfolded protein response (UPR) during endoplasmic reticulum (ER) stress by diverse intracellular (hypoxia, nutrient deprivation, etc.) or extracellular (environmental or drug induced) stimuli is considered a major threat for perturbing cellular homeostasis leading to the aggregation of unfolded proteins inside the cell. The catastrophic UPR events emerge as a prime cellular adaptation by remodeling cancer cell signaling and restoring ER homeostasis in favor of tumor growth. The transient ER stress protects cancer cells from undergoing apoptosis, whereas the prolonged stress response further activates many cell death pathways. The present review summarizes the UPR mediated triggering of transcriptional and translational reprogramming, which will provide novel therapeutic strategies towards pro-death mechanisms rather than a cellular adaptation in tumorigenesis. Nonetheless, the current topic also points out the reprogramming of emerging molecular switching events by complex UPR-mediated signaling to trigger apoptosis. The novel agents from various natural, semi-synthetic and synthetic sources that target ER stress signaling pathway to modulate selectively the UPR phenomena with preclinical efficacy are outlined. Since major emphasis on ER stress-induced transcriptional and translational reprogramming remains to be explored, we believe that the current subject will instigate more attention from the biomedical researchers in this certain research direction.

AKT is indispensable for coordinating Par-4/JNK cross talk in p21 downmodulation during ER stress

The double-edged role of p21 to command survival and apoptosis is emerging. The current investigation highlights ER stress-mediated JNK activation that plausibly triggers cell death by attenuating endogenous p21 level. Here, we demonstrated that ER stress activator 3-AWA diminishes the p21 levels in cancer cells by averting the senescent phenotype to commence G2/M arrest. In essence, the deceleration in p21 level occurs through ER stress/JNK/Caspase-3 axis via activation/induction of proapoptotic Par-4 and inhibition of AKT. The molecular dynamics studies identified important interactions, which may be responsible for the AKT inhibition and efficacy of 3-AWA towards AKT binding pocket. Interestingly, the p21 deceleration was rescued by incubating the cells with 3-AWA in the presence of an ER stress inhibitor, Salubrinal. Furthermore, we demonstrated that p21 expression decreases solitarily in Par-4^+/+ MEFs; albeit, ER stress-induced JNK activation was observed in both Par-4^+/+ and Par-4^−/− MEFs. Par-4 knockdown or overexpression studies established that ectopic Par-4 along with ER stress are not sufficient to downregulate p21 in PC-3 cells but are adequate for DU-145 cells and that the ER stress inflicted activation of JNK, inhibition of AKT and Par-4 induction are all crucial to p21 downmodulation by 3-AWA. By using isogenic cell lines, such as HCT-116 p53^+/+ and HCT-116 p53^−/−, we found that deceleration in p21 expression due to ER stress is p53 independent. Moreover, in orthotopic carcinogen-induced rat colorectal carcinoma model, we found that 3-AWA inhibits colorectal tumor growth and formation of colorectal polyps at a tolerable dose, similar to the first-line drug for colorectal cancer-5-fluorouracil.

P-channel thin film transistors using reduced graphene oxide

Chemically reduced graphene oxide (rGO) samples with various degrees of reduction were prepared using hydrazine hydrate as the reducing agent. Scanning tunnelling microscope imaging shows that rGO contains rows of randomly distributed patches of epoxy groups. The local density of states of the rGO samples were mapped with scanning tunnelling spectroscopy, which shows that the bandgap in rGO originates from the epoxide regions itself. The Fermi level of the epoxide regions is shifted towards the valence band, making rGO locally p-type and a range of bandgaps from 0-2.2 eV was observed in these regions. Thin film transistors were fabricated using rGO as the channel layer. The devices show excellent output characteristics with clear saturation and gate dependence. The transfer characteristics show that rGO behaves as a p-type semiconductor; the devices exhibit an on/off ratio of 10⁴, with a low-bias hole mobility of 3.9 cm² V^-1 s^-1.

Molecular diversity, recombination and population structure of alphasatellites associated with begomovirus disease complexes

The genus, begomovirus (family Geminiviridae) includes a large number of viruses infecting a wide range of plant species worldwide. The majority of monopartite begomoviruses are associated with satellites (betasatellites) and/or satellite-like molecules (alphasatellites). In spite of the Indo-China region being regarded as the centre of origin of begomoviruses and satellites, a detailed study on the emergence and evolution of alphasatellites in India has not yet conducted. Our present analysis indicated the association of 22 alphasatellites with monopartite and bipartite begomovirus-betasatellite complexes in India. Based on sequence pairwise identity, these alphasatellites were categorized into five distinct groups: Cotton leaf curl alphasatellite, Gossypium darwinii symptomless alphasatellite, Gossypium mustelinum symptomless alphasatellite, Okra leaf curl alphasatellite and an unreported Chilli leaf curl alphasatellite (ChiLCA). Furthermore, infectivity analysis of the cloned ChiLCA along with the viral components of either cognate or non-cognate chilli-infecting begomoviruses on Nicotiana benthamiana suggested that ChiLCA is dispensable for leaf curl disease development. It is noteworthy that in the presence of ChiLCA, a marginal decrease in betasatellite DNA level was noticed. Additionally, high genetic variability and diverse recombination patterns were detected among these alphasatellites, and the nucleotide substitution rate for the Rep gene of ChiLCA was determined to be 2.25×10-3nucleotides/site/year. This study highlights the genetic distribution, and likely contribution of recombination and nucleotide diversity in facilitating the emergence of alphasatellites.

A study on the effect of prolonged mobile phone use on pure tone audiometry thresholds of medical students of Sikkim

Introduction:

Mobile phones have become indispensable for daily activities, and people are exposed to them from an early age. There is, however, concern about the harmful effect of the electromagnetic radiation emitted from the mobile phones.

Objective:

The objective of the study was to study the effect of mobile phone on average pure tone audiometry (PTA) threshold of the person and to study the changes in the pure tone threshold at high frequencies such as 2 kHz, 4 kHz, and 8 kHz among the students with prolonged exposure to mobile phones.

Methodology:

A cross-sectional study was conducted among the medical students who have been using mobile phones for the past 5 years. The effect of mobile phones on the PTA threshold in the exposed ear and the nonexposed ear was assessed.

Results:

The study shows that there is a significant difference in average air conduction (AC) and bone conduction (BC) hearing threshold among the exposed and the nonexposed ears (P < 0.05). A significant rise of both AC and BC threshold at individual frequencies between the exposed and the nonexposed ear is also noted in this study.

Conclusion:

The study conducted shows changes in the hearing threshold of the exposed ear when compared with the nonexposed ear. There are however lot of unanswered questions which provide an interesting avenue for further research. Till concrete evidence is available the only feasible way to control its exposure is to limit the duration of usage of mobile phones.

Nucleotide composition and codon usage bias of SRY gene

The SRY gene is present within the sex-determining region of the Y chromosome which is responsible for maleness in mammals. The nonuniform usage of synonymous codons in the mRNA transcript for encoding a particular amino acid is the codon usage bias (CUB). Analysis of codon usage pattern is important to understand the genetic and molecular organisation of a gene. It also helps in heterologous gene expression, design of primer and synthetic gene. However, the analysis of codon usage bias of SRY gene was not yet studied. We have used bioinformatic tools to analyse codon usage bias of SRY gene across mammals. Codon bias index (CBI) indicated that the overall extent of codon usage bias was weak. The relative synonymous codon usage (RSCU) analysis suggested that most frequently used codons had an A or C at the third codon position. Compositional constraint played an important role in codon usage pattern as evident from correspondence analysis (CA). Significant correlation among nucleotides constraints indicated that both mutation pressure and natural selection affect the codon usage pattern. Neutrality plot suggested that natural selection might play a major role, while mutation pressure might play a minor role in codon usage pattern in SRY gene in different species of mammals.

Tolerance of weekly paclitaxel and carboplatin as neoadjuvant chemotherapy in advanced ovarian cancer patients who are unlikely to tolerate 3 weekly paclitaxel and carboplatin

OBJECTIVE

There are little data regarding safety and effectiveness of neoadjuvant chemotherapy (NACT) in patients who are considered unfit for receiving 3 weekly paclitaxel and carboplatin. The aim of this study was to study the toxicity and response rates of weekly paclitaxel and carboplatin as NACT in such cohort of patients.

METHODS

Study population included advanced ovarian cancer patients who were unlikely to tolerate 3 weekly paclitaxel and carboplatin and hence received weekly paclitaxel (80 mg/m2) and carboplatin AUC-2 as NACT. The data regarding the baseline characteristics, chemotherapy tolerance, completion rates, toxicity (CTCAE version 4.02), and radiological response rates are presented. SPSS version 16 was used for analysis. Descriptive statistics is presented.

RESULT

Eleven patients received this schedule. Nine patients completed nine cycles of NACT. Except one, all patients completed NACT with an average relative dose intensity of >0.8. There was no chemotherapy-related mortality. Grade 3-4 life-threatening complications were seen in two patients. The post NACT response rate was 100%.

CONCLUSION

Weekly paclitaxel and carboplatin chemotherapy is safe and efficacious in patients who are unsuitable for 3 weekly paclitaxel and carboplatin chemotherapy schedules.

An audit of cytoreductive surgeries in ovarian cancer from a rural based cancer center

BACKGROUND AND OBJECTIVE

Ovarian cancers are frequently seen at an advanced stage in our center. This audit was planned to see the morbidity and efficacy of different types of cytoreductive surgeries (radical vs. ultra-radical) done in such patients.

METHODS

This was a retrospective analysis of all ovarian cancer patients who underwent cytoreductive surgery at our center from January 2009 to August 2013. The case records of these patients were reviewed and the demographic, disease-related and treatment-related data were extracted.

RESULTS

Fifty-fivepatients were identified. Ten (18.2%) patients underwent primary cytoreduction while 45 patients had (81.8%) interval cytoreduction. The resections achieved were optimal in 50 patients (90.9%) and suboptimal in five patients (9.1%). The postoperative median blood loss was 400 (350-600) mL. The median time interval for surgery was 4.0 h (3-5 h). The type of resection achieved (optimal vs. suboptimal) was the only factor affecting the progression free survival (PFS) (Hazard ratio = 0.08 95% confidence interval 0.02-0.3). There was no significant difference in postoperative morbidity in patients undergoing the ultra-radical surgery as compared to those who underwent radical surgery.

CONCLUSION

Optimal cytoreduction may improve PFS in advanced ovarian cancer patients and needs to be done even if it mandates an ultra-radical surgery.

Development and validation of a questionnaire to measure preferences and expectations of patients undergoing palliative chemotherapy: EXPECT questionnaire

OBJECTIVE

The objective was to design and validate the questionnaire for capturing palliative chemotherapy-related preferences and expectations.

DESIGN

Single arm, unicentric, prospective observational study.

METHODS

EXPECT questionnaire was designed to capture preferences and expectations of patients undergoing palliative chemotherapy. This questionnaire underwent a linguistic validation and then was tested in patients. Ten patients are undergoing chemotherapy for solid tumors who fulfilled the inclusion and exclusion criteria self-administered the EXPECT questionnaire in regional language. After filling this questionnaire, they self-administered quick questionnaire-10 (QQ-10). SPSS version 16 (IBM New York) was used for analysis. Completion rate of EXPECT questionnaire was calculated. The feasibility, face validity, utility and time taken for completion of EXPECT questionnaire was also assessed.

RESULTS

The completion rate of this questionnaire was 100%. All patients completed questionnaire within 5 min. The QQ-10 tool confirmed the feasibility, face validity and utility of the questionnaire.

CONCLUSION

EXPECT questionnaire was validated in the regional language, and it's an effective tool for capturing patient's preferences and expectation from chemotherapy.

Evaluation of Risk Factors for Laryngopharyngeal Reflux among Sikkimese Population

Background Laryngopharyngeal reflux is a global health problem and is associated with a huge economic burden and decreased quality of life. Studies describing the epidemiology of laryngopharyngeal reflux are sparse in India and south east Asia. This study becomes significant as it is being conducted in Sikkimese population who resides in high altitude have a different lifestyle. Objective To evaluate the risk factors for laryngopharyngeal reflux among Sikkimese origin. Method Patients of Sikkimese origin visiting Ear Nose Throat outpatient department Were administered with validated questionnaire. The patients were further subjected to validate Reflux symptom Index score. Indirect laryngoscopy was performed to calculate reflux finding score. Presence of laryngopharyngeal reflux was identified with patients having reflux symptom index and reflux finding score of greater or equal to 13 or more and 7 or more. Result Out of 200 subjects analysed, there were 77(38.5%) male and 123(61.5%) female. Heartburn and regurgitation were the most common symptom among the masses. Hoarseness and frequent throat clearance were the commonest laryngopharyngeal reflux symptoms. Various risk factors were computed as mentioned in the results column. Conclusion Study on the above mentioned population differed from rest of the country in terms of dietary habits. Fermented food was found to be one of the important risk factor for the development of laryngopharyngeal reflux in the sikkimise population.