Characteristics of tunable aluminum-doped Ga2O3thin films and photodetectors.

Aluminum-doped Ga2O3(AGO) thin films were prepared by plasma-enhanced atomic layer deposition (PE-ALD). The growth mechanism, surface morphology, chemical composition, and optical properties of AGO films were systematically investigated. The bandgap of AGO films can be theoretically set between 4.65 and 6.8 eV. Based on typical AGO films, metal-semiconductor-metal photodetectors (PDs) were created, and their photoelectric response was examined. The preliminary results show that PE-ALD grown AGO films have high quality and tunable bandgap, and AGO PDs possess superior characterizations to undoped films. The AGO realized using PE-ALD is expected to be an important route for the development of a new generation of gallium oxide-based photodetectors into the deep-ultraviolet.

Clinical implications of micro lymph node metastasis for patients with gastric cancer.

BACKGROUND: Lymph node size is considered as a criterion for possible lymph node metastasis in imageology. Micro lymph nodes are easily overlooked by surgeons and pathologists. This study investigated the influencing factors and prognosis of micro lymph node metastasis in gastric cancer. METHODS: 191 eligible gastric cancer patients who underwent D2 lymphadenectomy from June 2016 to June 2017 in the Third Surgery Department at the Fourth Hospital of Hebei Medical University were retrospectively analyzed. Specimens were resected en bloc and the postoperative retrieval of micro lymph nodes was carried out by the operating surgeon for each lymph node station. Micro lymph nodes were submitted for pathological examination separately. According to the results of pathological results, patients were divided into the "micro-LNM (micro lymph node metastasis)" group (N = 85) and the "non micro-LNM" group (N = 106). RESULTS: The total number of lymph nodes retrieved was 10,954, of which 2998 (27.37%) were micro lymph nodes. A total of 85 (44.50%) gastric cancer patients had been proven to have micro lymph node metastasis. The mean number of micro lymph nodes retrieved was 15.7. The rate of micro lymph node metastasis was 8.1% (242/2998). Undifferentiated carcinoma (90.6% vs. 56.6%, P = 0.034) and more advanced Pathological N category (P < 0.001) were significantly related to micro lymph node metastasis. The patients with micro lymph node metastasis had a poor prognosis (HR for OS of 2.199, 95% CI = 1.335-3.622, P = 0.002). For the stage III patients, micro lymph node metastasis was associated with shorter 5-year OS (15.6% vs. 43.6%, P = 0.0004). CONCLUSIONS: Micro lymph node metastasis is an independent risk factor for poor prognosis in gastric cancer patients. Micro lymph node metastasis appears to be a supplement to N category in order to obtain more accurate pathological staging.

[Sc©[3]CPP]+: A Viable Metal-Centered [3]Cycloparaphenylene.

[n]Cycloparaphenylenes ([n]CPPs, n denotes the number of phenyl groups) are difficult to synthesize because of the strain related to their bent phenyl rings. In particular, the strain in [3]CPP is high enough to destroy the π electron delocalization, leading to the spontaneous structural transition to an energetically more stable "bond-shift" (BS) isomer ([3]BS). In this contribution, we propose to achieve [3]CPP by enhancing the π electron delocalization through hosting a guest metal atom. Our computations revealed that Sc could stabilize [3]CPP by forming the [Sc©[3]CPP]+ complex through the favorable π-Sc donation-backdonation interactions. Thermodynamically, the binding energy between the Sc atom and [3]CPP was -205.7 kcal/mol, which could well compensate not only the energy difference of 44.2 kcal/mol between [3]CPP and [3]BS but also the extremely high strain energy of 170.3 kcal/mol in [3]CPP. Simultaneously, the [Sc©[3]CPP]+ complex is stable up to 1500 K in dynamic simulations, suggesting its high viability in the synthesis.

Investigation of stretchable strain sensor based on CNT/AgNW applied in smart wearable devices.

Stretchable strain sensor, an important paradigm of wearable sensor which can be attached onto clothing or even human skin, is widely used in healthcare, human motion monitoring and human-machine interaction. Pattern-available and facile manufacturing process for strain sensor is pursued all the time. A carbon nanotube (CNT)/silver nanowire (AgNW)-based stretchable strain sensor fabricated by a facile process is reported here. The strain sensor exhibits a considerable Gauge factor of 6.7, long-term durability (>1000 stretching cycles), fast response and recovery (420 ms and 600 ms, respectively), hence the sensor can fulfill the measurement of finger movement. Accordingly, a smart glove comprising a sensor array and a flexible printed circuit board is assembled to detect the bending movement of five fingers simultaneously. Moreover, the glove is wireless and basically fully flexible, it can detect the finger bending of wearer and display the responses distinctly on an APP of a smart phone or a host computer. Our strain senor and smart glove will broaden the materials and applications of wearable sensors.

Influence of stepwise oxidation on the structure, stability, and properties of planar pentacoordinate carbon species CAl5.

Computational design has played an important role in planar hyper-coordinate carbon (phC) chemistry. However, none of numerous computationally predicted phC species were subsequently successfully synthesized in the condensed phase, perhaps due to the frustrating issue of oxidation. In the present work, we studied the influence of stepwise oxidation on the structure, stability, and properties of phC species using the milestone planar pentacoordinate carbon (ppC) species CAl5+ as an example. Our results indicated that the ppC structure of CAl5+ would be directly destroyed with one, two, or six O atom(s) per molecule present and indirectly with three or four O atoms, but maintained with five O atoms due to the ppC isomer of CAl5O5+ being a kinetically stable global energy minimum displaying σ and π double aromaticity. Moreover, the magnitudes of the first to fifth vertical oxygen affinities (VOAs) for CAl5+ were determined to be very high (-85.5 to -116.3 kcal mol-1), probably due to the existence of peripheral diffuse Al-Al bond(s). However, the sixth VOA was reduced significantly to -50.2 kcal mol-1, consistent with the absence of any diffuse Al-Al bond in the corresponding CAl5O5+ species. So CAl5O5+ may be insensitive to oxidation. Therefore, the ppC species D5h CAl5O5+ might be resistant to being degraded under a delicate control of oxidation level (producing five O atoms per CAl5+ molecule).

HOXC9 overexpression is associated with gastric cancer progression and a prognostic marker for poor survival in gastric cancer patients.

BACKGROUND: As a member of the homeobox family, HOXC9 is overexpressed in several malignant tumors and may be regarded as a biomarker for prognostic evaluation. However, the expression pattern and prognostic significance of HOXC9 in gastric cancer have not been detailedly studied. METHODS: HOXC9 mRNA expression difference in normal tissues and gastric cancer tissues were investigated using RT-PCR, and immunohistochemistry was used to analyze HOXC9 protein expression in precancerous lesions and gastric cancer at different stages, and its clinicopathological characteristics and survival were statistically tested. RESULTS: Compared to the normal gastric mucosa tissues, the expression levels of HOXC9 mRNA in the human gastric cancer tissues were significantly higher. HOXC9 protein levels of gastric cancer were obviously higher than that in other noncancerous tissues (P < 0.001). Positive expression of HOXC9 was associated with tumor size (P = 0.036), lymphatic invasion (P = 0.001), depth of invasion (P < 0.001), lymph-node metastasis (P < 0.001), and higher stage disease (P < 0.001). Furthermore, Kaplan-Meier survival curves showed that HOXC9 expression is inversely correlated with both disease-specific and disease-free 5 year survival of patients with gastric cancer (P < 0.001 for both). Strikingly, our multivariate Cox regression analysis revealed that HOXC9 expression was an independent poor prognostic factor in gastric cancer (P < 0.05). CONCLUSIONS: HOXC9 expression was observed in a subset of patients with gastric cancer and was associated with an unfavorable prognosis. As well as being a new prognostic indicator, HOXC9 protein could be a useful marker for early diagnosis.

Prevalence and genotype distribution of human papillomavirus among 9945 women from the Nanhai area of Foshan.

BACKGROUND: To provide a scientific basis for the prevention and treatment of cervical cancer (CC), we investigated the distribution characteristics and genotypes of human papillomavirus (HPV) and the prevalence of multiple HPV infections in women of different ages seeking management for abnormal cytology in Foshan City. METHODS: Screening for the 21 genotypes of HPV was carried out in 9945 females seeking management of abnormal cervical cytology results using rapid flow-through hybridization of nucleic acid molecules. The overall prevalence, genotype distribution and age-specific prevalence were examined. RESULTS: Our results indicate that the prevalence of overall, high-risk, intermediate-risk, and low-risk HPV infections was 13.5%, 12.1%, 1.3%, and 1.9%, respectively. Of the 1346 women who tested positive, 89.5% were positive for a single HPV genotype, and 10.5% were positive for ≥2 genotypes. The most frequently detected HPV genotype was HPV-16 (2.9%), followed by HPV-52 (2.9%), HPV-58 (1.5%), and HPV-CP8304 (1.0%). The highest infection prevalence was found in patients 21-30 years old (271/1670, 16.2%). CONCLUSION: The prevalence of HPV infection in women seeking management for abnormal cytology in Foshan City is highest in the younger population (21-30 years old). Similar to most previous surveys, HPV-58 and HPV-52 infections are as common as HPV-16 infection.

Viable aromatic BenHn stars enclosing a planar hypercoordinate boron or late transition metal.

Monocyclic Bn rings can act as n-electron σ-donors to stabilize a non-classical planar hypercoordinate atom at ring center, forming wheel-like structures. Herein, we report that BenHn rings can also serve as n-electron σ-donors to construct star-like structures including B©Be6H6+ and TM©Be7H7q (TM is a group 10-12 metal with q = -1, 0, and 1, respectively) by complying with octet or 18-electron rules. Electronic structure analyses show that these species are stabilized by the σ-donation and π-backdonation between the central atom and the peripheral BenHn ring, the favorable Coulomb attraction due to the negative-positive-negative charge population pattern on the central atom, the middle Ben layer, and the outer Hn layer, as well as the σ-π double aromaticity. Importantly, three of the ten species, including B©Be6H6+, Cu©Be7H7, and Au

Computational design of organometallic oligomers featuring 1,3-metal-carbon bonding and planar tetracoordinate carbon atoms.

Density functional theory computations (B3LYP) have been used to explore the chemistry of titanium-aromatic carbon "edge complexes" with 1,3-metal-carbon (1,3-MC) bonding between Ti and planar tetracoordinate Cß . The titanium-coordinated, end-capping chlorides are replaced with OH or SH groups to afford two series of difunctional monomers that can undergo condensation to form oxide- and sulfide-bridged oligomers. The sulfide-linked oligomers have less molecular strain and are more exergonic than the corresponding oxide-linked oligomers. The HOMO-LUMO gap of the oligomers varies with their composition and decreases with growing oligomer chain. This theoretical study is intended to enrich 1,3-MC bonding and planar tetracoordinate carbon chemistry and provide interesting ideas to experimentalists. Organometallic complexes with the TiE2 (E = OH and SH) decoration on the edge of aromatic hydrocarbons have been computationally designed, which feature 1,3-metal-carbon (1,3-MC) bonding between titanium and planar tetracoordinate ß-carbon. Condensation of these difunctional monomers by eliminating small molecules (H2O and H2S) produce chain-like oligomers. The HOMO-LUMO gaps of the oligomers decreases with growing oligomer chain, a trend that suggests possible semiconductor properties for oligomers with longer chains.

Linear, planar, and tubular molecular structures constructed by double planar tetracoordinate carbon D2hC2(BeH)4 species via hydrogen-bridged -BeH2Be- bonds.

This computational study identifies the rhombic D2hC2 (BeH)4 (2a) to be a species featuring double planar tetracoordinate carbons (ptCs). Aromaticity and the peripheral BeBeBeBe bonding around CC core contribute to the stabilization of the ptC structure. Although the ptC structure is not a global minimum, its high kinetic stability and its distinct feature of having a bonded C2 core from having two separated carbon atoms in the global minimum and other low-lying minima could make the ptC structure to be preferred if the carbon source is dominated by C2 species. The electron deficiency of the BeH group allows the ptC species to serve as building blocks to construct large/nanostructures, such as linear chains, planar sheets, and tubes, via intermolecular hydrogen-bridged bonds (HBBs). Formation of one HBB bond releases more than 30.0 kcal/mol of energy, implying the highly exothermic formation processes and the possibility to synthesize these nano-size structures.

The degree of π electron delocalization and the formation of 3D-extensible sandwich structures.

DFT B3LYP/6-31G(d) calculations were performed to examine the feasibility of graphene-like C42H18 and starbenzene C6(BeH)6 (SBz) polymers as ligands of 3D-extensible sandwich compounds (3D-ESCs) with uninterrupted sandwich arrays. The results revealed that sandwich compounds with three or more C42H18 ligands were not feasible. The possible reason may be the localization of π electrons on certain C6 hexagons due to π-metal interactions, which makes the whole ligand lose its electronic structure basis (higher degree of π electron delocalization) to maintain the planar structure. For comparison, with the aid of benzene (Bz) molecules, the SBz polymers can be feasible ligands for designing 3D-ESCs because the C-Be interactions in individual SBz are largely ionic, which will deter the π electrons on one C6 ring from connecting to those on neighbouring C6 rings. This means that high degree of π electron delocalization is not necessary for maintaining the planarity of SBz polymers. Such a locally delocalized π electron structure is desirable for the ligands of 3D-ESCs. Remarkably, the formation of a sandwich compound with SBz is thermodynamically more favourable than that found for bis(Bz)chromium. The assembly of 3D-ESCs is largely exothermic, which will facilitate future experimental synthesis. The different variation trends on the HOMO-LUMO gaps in different directions (relative to the sandwich axes) suggest that they can be developed to form directional conductors or semiconductors, which may be useful in the production of electronic devices.

Star-like superalkali cations featuring planar pentacoordinate carbon.

Superalkali cations, known to possess low vertical electron affinities (VEAs), high vertical detachment energies, and large highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gaps, are intriguing chemical species. Thermodynamically, such species need to be the global minima in order to serve as the promising targets for experimental realization. In this work, we propose the strategies of polyhalogenation and polyalkalination for designing the superalkali cations. By applying these strategies, the local-minimum planar pentacoordinate carbon (ppC) cluster CBe5 can be modified to form a series of star-like superalkali ppC or quasi-ppC CBe5X5 (+) (X = F, Cl, Br, Li, Na, K) cations containing a CBe5 moiety. Polyhalogenation and polyalkalination on the CBe5 unit may help eliminate the high reactivity of bare CBe5 molecule by covering the reactive Be atoms with noble halogen anions and alkali cations. Computational exploration of the potential energy surfaces reveals that the star-like ppC or quasi-ppC CBe5X5 (+) (X = F, Cl, Br, Li, Na, K) clusters are the true global minima of the systems. The predicted VEAs for CBe5X5 (+) range from 3.01 to 3.71 eV for X = F, Cl, Br and 2.12-2.51 eV for X = Li, Na, K, being below the lower bound of the atomic ionization potential of 3.89 eV in the periodic table. Large HOMO-LUMO energy gaps are also revealed for the species: 10.76-11.07 eV for X = F, Cl, Br and 4.99-6.91 eV for X = Li, Na, K. These designer clusters represent the first series of superalkali cations with a ppC center. Bonding analyses show five Be-X-Be three-center two-electron (3c-2e) σ bonds for the peripheral bonding, whereas the central C atom is associated with one 6c-2e π bond and three 6c-2e σ bonds, rendering (π and σ) double aromaticity. Born-Oppenheimer molecular dynamics simulations indicate that the CBe5 motif is robust in the clusters. As planar hypercoordination carbon species are often thermodynamically unstable and highly reactive, the superalkali cation characters of these ppC species should be highlighted, which may be suitable for experimental realization.

Ultrashort Beryllium-Beryllium Distances Rivalling Those of Metal-Metal Quintuple Bonds Between Transition Metals.

Chemical bonding is at the heart of chemistry. Recent work on high bond orders between homonuclear transition metal atoms has led to ultrashort metal-metal (TM-TM) distances defined as dM-M <1.900 Å. The present work is a computational design and characterization of novel main group species containing ultrashort metal-metal distances (1.728-1.866 Å) between two beryllium atoms in different molecular environments, including a rhombic Be2 X2 (X=C, N) core, a vertical Be-Be axis in a 3D molecular star, and a horizontal Be-Be axis supported by N-heterocyclic carbene (NHC) ligands. The ultrashort Be-Be distances are achieved by affixing bridging atoms to attract the beryllium atoms electrostatically or covalently. Among these species are five global minima and one chemically viable diberyllium complex, which provide potential targets for experimental realization.

ZEB2-Sp1 cooperation induces invasion by upregulating cadherin-11 and integrin α5 expression.

Epithelial-mesenchymal transition (EMT) is a process implicated in invasion and metastasis. EMT is characterized by repression of epithelial markers and induction of mesenchymal markers. ZEB2 is a transcriptional repressor of E-cadherin, leading to EMT. Previously, we have shown that ZEB2 directly upregulates integrin α5 transcription by cooperating with the transcription factor Sp1. In this study, we investigated the precise mechanism by which ZEB2 modulates invasion and EMT events and the role of Sp1 in ZEB2-induced invasion. We found that ZEB2 directly induced cadherin-11 transcription in an Sp1-dependent, but Smad- and E-box-independent, manner and repressed E-cadherin expression in an Sp1- and Smad-independent manner, leading to cadherin switch. Furthermore, ZEB2 upregulated Sp1 by enhancing Sp1 protein stability, and Sp1 was found to be critical for ZEB2-induced cancer cell invasion, mainly through induction of cadherin-11 and integrin α5. Expression levels of cadherin-11 and integrin α5 were interdependent and both modulated c-Jun N-terminal kinase-signaling activity and invasion. Immunofluorescence analysis showed that nuclear expression of ZEB2 was positively correlated with Sp1 expression in human colorectal cancers. Together, these findings demonstrate a previously unrecognized interplay between ZEB2, Sp1, cadherin-11 and integrin α5 that is, probably, significant in tumor progression and metastasis.

[Effect and mechanisms of TET on human gastric carcinoma cell line SGC7901 and SGC7901/ADR].

OBJECTIVE: To investigate the effect of tetrandrine (TET) on zinc finger protein 139 (ZNF139) and multidrug resistance (MDR) of human gastric carcinoma cell lines and possible mechanisms. METHODS: Cultured SGC7901 and SGC7901/ADR were treated with TET (0.5, 1.0, 1.5, 2.0, and 2.5 microg/mL), then inhibition rates were measured by MTT assay in vitro. The expressions of ZNF139, MRP-1, MDR1, and GST-pi were detected by RT-PCR. The correlation between ZNF139 and each multidrug resistance factor was analyzed using Spearman correlation analysis, and the coefficient correlation was calculated. RESULTS: The inhibition rate of TET (< or = 2.0 microg/mL) for SGC7901 and SGC7901/ADR was less than 10% with MTT assay. Expressions of ZNF139, MRP-1, MDR1, and GST-pi mRNA were higher in SGC7901/ADR than in SGC7901 (all P < 0.05). The expressions of ZNF139, MRP-1, MDR1, and GST--pi were down-regulated in SGC7901/ADR cells efficiently (all P < 0.01). Positive correlation existed between ZNF139 and MRP-1, ZNF139 and MDR1 before treated by TET in SGC7901/ADR, and this relationship also existed in SGC7901/ADR cells after treated by TET (all P < 0.05). CONCLUSION: TET could achieve MDR reversion in gastric cancer cells by down-regulating the expression of ZNF139, MRP-1, and MDR1.

Comparative analysis of two digestive tract reconstruction methods in total laparoscopic radical total gastrectomy.

BACKGROUND: The incidence of gastric cancer has significantly increased in recent years. Surgical resection is the main treatment, but the method of digestive tract reconstruction after gastric cancer surgery remains controversial. In the current study, we sought to explore a reasonable method of digestive tract reconstruction and improve the quality of life and nutritional status of patients after surgery. To this end, we statistically analyzed the clinical results of patients with gastric cancer who underwent jejunal interposition double-tract reconstruction (DTR) and esophageal jejunum Roux-en-Y reconstruction (RY). AIM: To explore the application effect of DTR in total laparoscopic radical total gastrectomy (TLTG) and evaluate its safety and efficacy. METHODS: We collected the relevant data of 77 patients who underwent TLTG at the Fourth Hospital of Hebei Medical University from October 2021 to January 2023. Among them, 35 cases were treated with DTR, and the remaining 42 cases were treated with traditional RY. After 1:1 propensity score matching, the cases were grouped into 31 cases per group, with evenly distributed data. The clinical characteristics and short- and long-term clinical outcomes of the two groups were statistically analyzed. RESULTS: The two groups showed no significant differences in basic data, intraoperative blood loss, number of lymph node dissections, first defecation time after operation, postoperative hospital stay, postoperative complications, and laboratory examination results on the 1st, 3rd, and 5th days after operation. The operation time of the DTR group was longer than that of the RY group [(307.58 ± 65.14) min vs (272.45 ± 62.09) min, P = 0.016], but the first intake of liquid food in the DTR group was shorter than that in the RY group [(4.45 ± 1.18) d vs (6.0 ± 5.18) d, P = 0.028]. The incidence of reflux heartburn (Visick grade) and postoperative gallbladder disease in the DTR group was lower than that in the RY group (P = 0.033 and P = 0.038). Although there was no significant difference in body weight, hemoglobin, prealbumin, and albumin between the two groups at 1,3 and 6 months after surgery, the diet of patients in the DTR group was better than that in the RY group (P = 0.031). CONCLUSION: The clinical effect of DTR in TLTG is better than that of RY, indicating that it is a more valuable digestive tract reconstruction method in laparoscopic gastric cancer surgery.

A propensity score-matched case-control comparative study of laparoscopic and open extended (D2) lymph node dissection for distal gastric carcinoma.

BACKGROUND: Technical proficiency at laparoscopic D2 lymph node dissection (LND) is essential for extending the use of laparoscopic surgery beyond the treatment of early gastric cancer (EGC). The aim of this study was to evaluate the technical and oncological feasibility of laparoscopic distal gastrectomy (LDG) with D2 LND for distal gastric cancer. METHODS: Of 922 patients who underwent open or LDG with D2 LND for gastric carcinoma, 133 treated by LDG and 133 treated by open distal gastrectomy (ODG) were selected using the propensity score matching method. The short-term surgical outcomes and long-term survivals of these matched groups were compared. RESULTS: The two study groups were well matched with respect to age, sex, body mass index, comorbidity, ASA score, abdominal operation history, and tumor stage. The LDG group had a significantly longer mean operating time (227 vs. 161 min, p < 0.001) but showed significantly less intraoperative blood loss (149 vs. 189 ml, p = 0.007). Total numbers of collected lymph nodes were similar in the two groups. Postoperatively, no significant intergroup differences were found for hospital stay, morbidity, or mortality. Furthermore, overall survivals were similar in the two groups (p = 0.621). Multivariate analysis showed that male gender, age ≥70 years, and intraoperative blood loss of ≥200 ml were independent risk factors of postoperative morbidity. CONCLUSIONS: Laparoscopic D2 LND for distal gastric cancer is technically safe and feasible compared with ODG. A prospective randomized trial is warranted to evaluate long-term oncological outcomes in advanced gastric carcinoma.

Value of serum procalcitonin levels in predicting spontaneous bacterial peritonitis.

BACKGROUND/AIMS: Spontaneous bacterial peritonitis (SBP) is a life-threatening disease that poses a great diagnostic challenge to clinicians. We aimed to systemically and quantitatively summarize the current evidence on the diagnostic value of the procalcitonin (PCT) test in identifying SBP. METHODOLOGY: We searched EMBASE, MEDLINE, the Cochrane database and reference lists of relevant articles with no language restrictions through May 2012. We selected original research that reported the diagnostic performance of PCT alone or compared with other biomarkers to diagnose SBP. We summarized test performance characteristics using forest plots, summary receiver operating characteristic curves and bivariate random effects models. RESULTS: We found only three qualifying studies examining 181 episodes of suspected infection with 50 (27.6%) confirmed SBP episodes from 3 countries. Bivariate pooled sensitivity, specificity, positive likelihood ratios and negative likelihood ratios were 86% (95%CI: 73%-94%), 80% (95%CI: 72%-87%), 7.73 (95%CI: 0.91-65.64) and 0.14 (95%CI: 0.01-1.89), respectively. The global measures of accuracy, area under the receiver operating curve (AUROC) and diagnostic odds ratio (DOR), showed PCT has excellent discriminative capability and individual study showed serum PCT testing has better accuracy than ascitic PCT, serum CRP or IL-6 testing. There was evidence of significant heterogeneity but no evidence of publication bias. CONCLUSIONS: The existing literature suggests moderate to high accuracy for PCT as a diagnostic aid for SBP. However, larger, appropriately designed prospective studies are needed to conclusively address the value of serum PCT testing in SBP diagnosis.

Tumor chemosensitivity is correlated with expression of multidrug resistance associated factors in variously differentiated gastric carcinoma tissues.

BACKGROUND/AIMS: To evaluate the relationship between chemosensitivities in vitro and expressions of multidrug resistance (MDR) associated factors in differentiated gastric carcinomas. METHODOLOGY: Gastric carcinomas tissues of varying degree of differentiation (65 cases) were collected and chemosensitivities to 5-FU, HCPT, PTX, L-OHP, CDDP and eADM were detected by sulphorhodamine B (SRB) assay, and expressions of P-gp, GST-π, Topo IIα, p53, Bcl-2, Bax and Survivin were tested by immunohistochemical staining. RESULTS: Inhibition rates of 5-FU, L-OHP and CDDP for well differentiated tumors were lower than those of poorly differentiated tumors (p<0.05). Expressions of P-gp, Bcl-2 and Survivin were higher in well differentiated than in poorly differentiated carcinomas (p<0.05); while expression of Topo IIα in well differentiated carcinomas was lower than in poorly differentiated carcinomas (p<0.05). The expression of MDR factors was different between well and poorly differentiated carcinomas. CONCLUSIONS: Different MDR characteristics were exhibited in well and poorly differentiated gastric carcinomas, which may be caused by different expressed MDR associated factors in these tissues.

Histological complete response after neoadjuvant XELOX in advanced gastric carcinoma.

We report on a case of a 65-year-old Chinese male with locally advanced gastric adenocarcinoma achieving pathological complete response after neoadjuvant chemotherapy with capecitabine and oxaliplatin (XELOX) regimen. He underwent esophagogastroduodenoscopy, which revealed a 6x5cm gastric ulcer. Biopsy of gastric ulcer revealed adenocarcinoma. Further workups with abdominal enhancement computed tomography (CT) staged his cancer as T4N2M0. He received 2 cycles of neoadjuvant chemotherapy with XELOX without severe toxicity. Afterwards, he underwent curative surgery consisting of total gastrectomy with extended D2 lymph node dissections and a Roux-en-Y esophagojejunostomy. On microscopic examination, no tumor cells were detected in the ulcer scar of the resected stomach and in the regional lymph nodes. The benefit of XELOX regimen as neoadjuvant chemotherapy in gastric cancer is worth further investigation.