MicroRNA-7 Regulates Migration and Chemoresistance in Non-Hodgkin Lymphoma Cells Through Regulation of KLF4 and YY1.

The discovery and description of the role of microRNAs has become very important, specifically due to their participation in the regulation of proteins and transcription factors involved in the development of cancer. microRNA-7 (miR-7) has been described as a negative regulator of several proteins involved in cancer, such as YY1 and KLF4. We have recently reported that YY1 and KLF4 play a role in non-Hodgkin lymphoma (NHL) and that the expression of KLF4 is regulated by YY1. Therefore, in this study we analyzed the role of miR-7 in NHL through the negative regulation of YY1 and KLF4. qRT-PCR showed that there is an inverse expression of miR-7 in relation to the expression of YY1 and KLF4 in B-NHL cell lines. The possible regulation of YY1 and KLF4 by miR-7 was analyzed using the constitutive expression or inhibition of miR-7, as well as using reporter plasmids containing the 3 'UTR region of YY1 or KLF4. The role of miR-7 in NHL, through the negative regulation of YY1 and KLF4 was determined by chemoresistance and migration assays. We corroborated our results in cell lines, in a TMA from NHL patients including DLBCL and follicular lymphoma subtypes, in where we analyzed miR-7 by ISH and YY1 and KLF4 using IHC. All tumors expressing miR-7 showed a negative correlation with YY1 and KLF4 expression. In addition, expression of miR-7 was analyzed using the GEO Database; miR-7 downregulated expression was associated with pour overall-survival. Our results show for the first time that miR-7 is implicate in the cell migration and chemoresistance in NHL, through the negative regulation of YY1 and KLF4. That also support the evidence that YY1 and KLF4 can be a potential therapeutic target in NHL.

Exoenzyme-producing halophilic bacteria from the former Lake Texcoco: identification and production of n-butyl oleate and bioactive peptides.

Halophilic bacterias from saline soil from former Lake Texcoco were isolated, identified based on 16 rRNA and tested to produce glucolytic, nucleolytic, proteolytic and lipolytic exoenzymes. The Bacillus, Virgibacillus, Kocuria, Salinicoccus, Gracilibacillus, Halobacillus, Tenuibacillus and Nesterekonia genera where identified. Lipase/eserases and proteases from Nesterenkonia sp. and Nesterenkonia aethiopica showed halotolerant characteristics and were selected to synthesize the oleochemical n-butyl oleate and antioxidant peptides from muscle protein of common carp (Cyprinus carpio), respectively. In organic media (2,2,4-Trimethylpentane), the lipase/esterases from Nesterenkonia sp. (0.6 U/mL) and N. aethiopica (1.2 U/mL) achieved a 62.7% and 53.2% of n-butyl oleate conversion, respectively. The protein hydrolysis from muscle of common carp (C. carpio) showed a degree of hydrolysis of 4.5 ± 0.2% and 2.8 ± 0.1% when proteases from Nesterenkonia sp. and N. aethiopica were used, respectively. Three peptidic fractions ranging molecular masses between 254 and 1002 Da [M + H] show antioxidant scavenging activity, and the principal fraction with a peptide of 547.3 Da [M + H] showed an inhibition of 37.7 ± 1.8% and 16.3 ± 0.6%, when 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) were used, respectively. These findings showed that the enzymatic battery of the halophilic bacteria from former lake Texcoco can be used in hydrolysis and synthesis of molecules with applications in different fields as food technology or bioenergy.

Regulation of Krüppel-Like Factor 4 (KLF4) expression through the transcription factor Yin-Yang 1 (YY1) in non-Hodgkin B-cell lymphoma.

Krüppel-Like Factor 4 (KLF4) is a member of the KLF transcription factor family, and evidence suggests that KLF4 is either an oncogene or a tumor suppressor. The regulatory mechanism underlying KLF4 expression in cancer, and specifically in lymphoma, is still not understood. Bioinformatics analysis revealed two YY1 putative binding sites in the KLF4 promoter region (-950 bp and -105 bp). Here, the potential regulation of KLF4 by YY1 in NHL was analyzed. Mutation of the putative YY1 binding sites in a previously reported system containing the KLF4 promoter region and CHIP analysis confirmed that these binding sites are important for KLF4 regulation. B-NHL cell lines showed that both KLF4 and YY1 are co-expressed, and transfection with siRNA-YY1 resulted in significant inhibition of KLF4. The clinical implications of YY1 in the transcriptional regulation of KLF4 were investigated by IHC in a TMA with 43 samples of subtypes DLBCL and FL, and all tumor tissues expressing YY1 demonstrated a correlation with KLF4 expression, which was consistent with bioinformatics analyses in several databases. Our findings demonstrated that KLF4 can be transcriptionally regulated by YY1 in B-NHL, and a correlation between YY1 expression and KLF4 was found in clinical samples. Hence, both YY1 and KLF4 may be possible therapeutic biomarkers of NHL.

Pattern classification of endocervical adenocarcinoma: reproducibility and review of criteria.

Previously, our international team proposed a three-tiered pattern classification (Pattern Classification) system for endocervical adenocarcinoma of the usual type that correlates with nodal disease and recurrence. Pattern Classification-A tumors have well-demarcated glands lacking destructive stromal invasion or lymphovascular invasion, Pattern Classification-B tumors show localized, limited destructive invasion arising from A-type glands, and Pattern Classification-C tumors have diffuse destructive stromal invasion, significant (filling a 4 × field) confluence, or solid architecture. Twenty-four cases of Pattern Classification-A, 22 Pattern Classification-B, and 38 Pattern Classification-C from the tumor set used in the original description were chosen using the reference diagnosis originally established. One H&E slide per case was reviewed by seven gynecologic pathologists, four from the original study. Kappa statistics were prepared, and cases with discrepancies reviewed. We found a majority agreement with reference diagnosis in 81% of cases, with complete or near-complete (six of seven) agreement in 50%. Overall concordance was 74%. Overall kappa (agreement among pathologists) was 0.488 (moderate agreement). Pattern Classification-B has lowest kappa, and agreement was not improved by combining B+C. Six of seven reviewers had substantial agreement by weighted kappas (>0.6), with one reviewer accounting for the majority of cases under or overcalled by two tiers. Confluence filling a 4 × field, labyrinthine glands, or solid architecture accounted for undercalling other reference diagnosis-C cases. Missing a few individually infiltrative cells was the most common cause of undercalling reference diagnosis-B. Small foci of inflamed, loose or desmoplastic stroma lacking infiltrative tumor cells in reference diagnosis-A appeared to account for those cases up-graded to Pattern Classification-B. In summary, an overall concordance of 74% indicates that the criteria can be reproducibly applied by gynecologic pathologists. Further refinement of criteria should allow use of this powerful classification system to delineate which cervical adenocarcinomas can be safely treated conservatively.

HPV frequency in penile carcinoma of Mexican patients: important contribution of HPV16 European variant.

The role of human papillomavirus (HPV) infection in penile carcinoma (PeC) is currently reported and about half of the PeC is associated with HPV16 and 18. We used a PCR-based strategy by using HPV general primers to analyze 86 penile carcinomas paraffin-embedded tissues. Some clinical data, the histological subtype, growth pattern, and differentiation degree were also collected. The amplified fragments were then sequenced to confirm the HPV type and for HPV16/18 variants. DNA samples were also subjected to relative real time PCR for hTERC gene copy number. Some clinical data were also collected. Global HPV frequency was 77.9%. Relative contributions was for HPV16 (85%), 31 (4.4%), 11 (4.4%), 58, 33, 18, and 59 (1.4% each one). Sequence analysis of HPV16 identified European variants and Asian-American (AAb-c) variants in 92% and in 8% of the samples, respectively. Furthermore hTERC gene amplification was observed in only 17% of the cases. Our results suggest that some members of HPV A9 group (represented by HPV16, 58, and 31) are the most frequent among PeC patients studied with an important contribution from HPV16 European variant. The hTERC gene amplification could be poorly related to penile epithelial tissue.

Heterologous production of cellobiose dehydrogenases from the basidiomycete Coprinopsis cinerea and the ascomycete Podospora anserina and their effect on saccharification of wheat straw.

Cellobiose dehydrogenases (CDHs) are extracellular glycosylated haemoflavoenzymes produced by many different wood-degrading and phytopathogenic fungi. Putative cellobiose dehydrogenase genes are recurrently discovered by genome sequencing projects in various phylogenetically distinct fungi. The genomes from the basidiomycete Coprinopsis cinerea and the ascomycete Podospora anserina were screened for candidate cdh genes, and one and three putative gene models were evidenced, respectively. Two putative cdh genes were selected and successfully expressed for the first time in Aspergillus niger. CDH activity was measured for both constructions (CDHcc and CDHpa), and both recombinant CDHs were purified to homogeneity and subsequently characterised. Kinetic constants were determined for several carbohydrates including ß-1,4-linked di- and oligosaccharides. Optimal temperature and pH were 60 °C and 5 for CDHcc and 65-70 °C and 6 for CDHpa. Both CDHs showed a broad range of pH stability between 4 and 8. The effect of both CDHs on saccharification of micronized wheat straw by an industrial Trichoderma reesei secretome was determined. The addition of each CDH systematically decreased the release of total reducing sugars, but to different extents and according to the CDH concentration. Analytical methods were carried out to quantify the release of glucose, xylose and gluconic acid. An increase of glucose and xylose was measured at a low CDHcc concentration. At moderated and high CDHcc and CDHpa concentrations, glucose was severely reduced with a concomitant increase of gluconic acid. In conclusion, these results give new insights into the physical and chemical parameters and diversity of basidiomycetous and ascomycetous CDHs. These findings also demonstrated that CDH drastically influenced the saccharification on a natural substrate, and thus, CDH origin, concentration and potential enzymatic partners should be carefully considered in future artificial secretomes for biofuel applications.

Changes in the bacterial populations of the highly alkaline saline soil of the former lake Texcoco (Mexico) following flooding.

Flooding an extreme alkaline-saline soil decreased alkalinity and salinity, which will change the bacterial populations. Bacterial 16S rDNA libraries were generated of three soils with different electrolytic conductivity (EC), i.e. soil with EC 1.7 dS m(-1) and pH 7.80 (LOW soil), with EC 56 dS m(-1) and pH 10.11 (MEDIUM soil) and with EC 159 dS m(-1) and pH 10.02 (HIGH soil), using universal bacterial oligonucleotide primers, and 463 clone 16S rDNA sequences were analyzed phylogenetically. Library proportions and clone identification of the phyla Proteobacteria, Actinobacteria, Acidobacteria, Cyanobacteria, Bacteroidetes, Firmicutes and Cloroflexi showed that the bacterial communities were different. Species and genera of the Rhizobiales, Rhodobacterales and Xanthomonadales orders of the alpha- and gamma-subdivision of Proteobacteria were found at the three sites. Species and genera of the Rhodospirillales, Sphingobacteriales, Clostridiales, Oscillatoriales and Caldilineales were found only in the HIGH soil, Sphingomonadales, Burkholderiales and Pseudomonadales in the MEDIUM soil, Myxococcales in the LOW soil, and Actinomycetales in the MEDIUM and LOW soils. It was found that the largest diversity at the order and species level was found in the MEDIUM soil as bacteria of both the HIGH and LOW soils were found in it.

Phylogenetic analysis of the archaeal community in an alkaline-saline soil of the former lake Texcoco (Mexico).

The soil of the former lake Texcoco is an extreme environment localized in the valley of Mexico City, Mexico. It is highly saline and alkaline, where Na+, Cl(-), HCO3(-) and CO3(2-) are the predominant ions, with a pH ranging from 9.8 to 11.7 and electrolytic conductivities in saturation extracts from 22 to 150 dS m(-1). Metagenomic DNA from the archaeal community was extracted directly from soil and used as template to amplify 16S ribosomal gene by PCR. PCR products were used to construct gene libraries. The ribosomal library showed that the archaeal diversity included Natronococcus sp., Natronolimnobius sp., Natronobacterium sp., Natrinema sp., Natronomonas sp., Halovivax sp., "Halalkalicoccus jeotgali" and novel clades within the family of Halobacteriaceae. Four clones could not be classified. It was found that the archaeal diversity in an alkaline-saline soil of the former lake Texcoco, Mexico, was low, but showed yet uncharacterized and unclassified species.

[Analysis of the decrease in mortality due to cervical cancer at the Mexican Institute of Social Security, from 1991 to 2005]. / Análisis del descenso de la mortalidad por cáncer cervicouterino en el IMSS, 1991-2005.

OBJECTIVE: to analyze the decrease in mortality due to cervical cancer in insured population of the Mexican Institute of Social Security (IMSS) and its relation to changes in the organization of the Program for Prevention and Control of Cervical Cancer (PCCaCu). MATERIAL AND METHODS: a descriptive study in which the annual rates of national mortality due to cervical cancer was analyzed from 1991 to 2005 was carried out. Information of deaths due to cervical cancer was obtained from the IMSS Mortality System (SISMOR), a database that identifies deaths occurred in insured population user of IMSS. The tendency was compared in three periods: I. 1991-1995, reorganization of the original program, II. 1996-2000, transition, and III. 2001-2005, incorporation to PREVENIMSS strategy. RESULTS: between 1991 and 2005, the mortality rate due to cervical cancer by 100 thousand women older than 24 years, decreased from 16.2 to 8.9 (45.1%). Between 1991 and 1995, the mortality rate increased 4.9%; between 1996 and 2000, it decreased 27% and in the last period, 2001-2005, it decreased 29.4%. The only differences that were statistically significant were the ones between the transition and the consolidation periods. The greatest decrease was registered when the PCCaCu was incorporated to PREVENIMSS strategy. CONCLUSIONS: the acceleration in the decrease of mortality rate due to cervical cancer can be explained by the reorganization and expansion of PCCaCu to target population and its incorporation to PREVENIMSS.

[Global expression analysis in uterine cervical cancer: metabolic pathways and altered genes]. / Análisis de expresión global del cáncer cérvico uterino: rutas metabólicas y genes alterados.

High risk human papillomavirus (HPV) infection is considered to be the most important etiological factor of Cervical Uterine Cancer. In order to determine the global expression pattern and to identify possible molecular markers of cervical cancer, cDNA arrays with probe sets complementary to 8,000 human genes were used to examine the expression profiles among 5 cell lines derived from human cervical cancer, three HPV16(+) tumor samples and three normal cervical tissues HPV(-). The levels of expression of different cellular processes were identified. Hierarchical clustering was performed and the gene expression using RT-PCR was confirmed. Two genes were found to be consistently overexpressed in invasive cervical cancer biopsies; one of them, IL-6 was previously reported to be overexpressed in cervical cancer and one novel gene, MMP10, previously not known to be related to cervical cancer. Hierarchical clustering of the expression data revealed that samples with common HPV type infection grouped together, maybe this could mean that differences between HPV types could be indirectly determined by expression profiles.

A molecular analysis by gene expression profiling reveals Bik/NBK overexpression in sporadic breast tumor samples of Mexican females.

BACKGROUND: Breast cancer is one of the most frequent causes of death in Mexican women over 35 years of age. At molecular level, changes in many genetic networks have been reported as associated with this neoplasia. To analyze these changes, we determined gene expression profiles of tumors from Mexican women with breast cancer at different stages and compared these with those of normal breast tissue samples. METHODS: 32P-radiolabeled cDNA was synthesized by reverse transcription of mRNA from fresh sporadic breast tumor biopsies, as well as normal breast tissue. cDNA probes were hybridized to microarrays and expression levels registered using a phosphorimager. Expression levels of some genes were validated by real time RT-PCR and immunohistochemical assays. RESULTS: We identified two subgroups of tumors according to their expression profiles, probably related with cancer progression. Ten genes, unexpressed in normal tissue, were turned on in some tumors. We found consistent high expression of Bik gene in 14/15 tumors with predominant cytoplasmic distribution. CONCLUSION: Recently, the product of the Bik gene has been associated with tumoral reversion in different neoplasic cell lines, and was proposed as therapy to induce apoptosis in cancers, including breast tumors. Even though a relationship among genes, for example those from a particular pathway, can be observed through microarrays, this relationship might not be sufficient to assign a definitive role to Bik in development and progression of the neoplasia. The findings herein reported deserve further investigation.

Análisis de expresión global del cáncer cérvico uterino: rutas metabólicas y genes alterados / Global expression analysis in uterine cervical cancer: Metabolic pathways and altered genes

High risk human papillomavirus (HPV) infection is considered to be the most important etiological factor of Cervical Uterine Cancer. In order to determine the global expression pattern and to identify possible molecular markers of cervical cancer, cDNA arrays with probe sets complementary to 8,000 human genes were used to examine the expression profiles among 5 cell lines derived from human cervical cancer, three HPV16(+) tumor samples and three normal cervical tissues HPV(-). The levels of expression of different cellular processes were identified. Hierarchical clustering was performed and the gene expression using RT-PCR was confirmed. Two genes were found to be consistently overexpressed in invasive cervical cancer biopsies; one of them, IL-6 was previously reported to be overexpressed in cervical cancer and one novel gene, MMP10, previously not known to be related to cervical cancer. Hierarchical clustering of the expression data revealed that samples with common HPV type infection grouped together, maybe this could mean that differences between HPV types could be indirectly determined by expression profiles.

La infección por virus de papiloma de alto riesgo (VPH) es considerada como el factor etiológico más importante del cáncer cérvico uterino (CaCU). Con el fin de determinar el patrón de expresión global e identificar algunos posibles genes marcadores del CaCU, se utilizaron microhileras de DNA que contenían 8,000 secuencias que codificaban para transcritos diferentes, para estudiar los perfiles de expresión de cinco líneas celulares derivadas de CaCU, tres muestras tumorales conteniendo VPH 16 y tres muestras normales negativas para la presencia de VPH. Se identificaron los niveles de expresión de genes relacionados con diferentes rutas metabólicas. Se llevó a cabo el análisis de agrupamiento jerárquico y posteriormente se confirmó la sobrexpresión de dos genes mediante RT-PCR. Estos dos genes se encontraron sobrexpresados en biopsias tumorales cervicales. Uno de ellos, el gen de IL6, que ha sido previamente reportado en relación con CaCU, así como el gen de la matriz-metaloproteasa 10 (MMP10) por primera vez relacionado con esta neoplasia. El análisis de agrupamiento jerárquico, además, reveló que las muestras que contienen el mismo tipo viral están asociadas, sugiriendo posibles diferencias en expresión entre tipos virales.

Prognostic significance of circumferential margin involvement in rectal adenocarcinoma treated with preoperative chemoradiotherapy and low anterior resection.

INTRODUCTION: Histologic examination of circumferential margins is an important predictor of local and distant relapse in non-radiated rectal cancer. However, for patients who received preoperative chemoradiotherapy this role has not yet been addressed. METHODS: From January 1995 to December 1997, 61 patients with rectal adenocarcinoma located between 0 and 10 cm from anal verge with invasion into perirectal fat assessed by rectal ultrasound were included. All patients received 45 Gy + bolus infusion of 5-FU (450 mg/m(2)/days 1-5, 28-33 of RT); 4-6 weeks later, surgery was performed. Circumferential margin was assessed (<2 mm was considered as positive). Five-year survival was calculated by Kaplan-Meier method and comparison of groups with log-rank test. Multivariate Cox regression analysis was performed to find risk factors affecting local control and survival. RESULTS: There were 35 males and 26 females, mean age 60.3 years. Twelve patients (19.7%) had circumferential margin involvement. Median follow-up was 44 months. Overall local recurrence was observed in 6 of 61 patients (9.8%); in patients without circumferential margin involvement this was 8%, whereas it was 16% in those with circumferential margin involvement (P = 0.33). Distant recurrence was observed in 22% of patients without circumferential margin involvement; conversely, it was 58.3% in those with involvement (P = 0.02). Five-year survival of patients without circumferential resection involvement margin was 81%, while it was 42% in patients with circumferential involvement (P = 0.006). CONCLUSIONS: In patients with rectal cancer treated by preoperative chemoradiation plus total mesorectal excision (TME) and sphincter saving surgery, circumferential margin involvement is associated with high incidence of distant recurrence and cancer-related death.

The role of surgery in primary gastric lymphoma: results of a controlled clinical trial.

OBJECTIVE: We began a controlled clinical trial to assess efficacy and toxicity of surgery (S), surgery + radiotherapy (SRT), surgery + chemotherapy (SCT), and chemotherapy (CT) in the treatment of primary gastric diffuse large cell lymphoma in early stages: IE and II1. SUMMARY BACKGROUND DATA: Management of primary gastric lymphoma remains controversial. No controlled clinical trials have evaluated the different therapeutic schedules, and prognostic factors have not been identified in a uniform population. PATIENTS AND METHODS: Five hundred eighty-nine patients were randomized to be treated with S (148 patients), SR (138 patients), SCT (153 patients), and CT (150 patients). Radiotherapy was delivered at doses of 40 Gy; chemotherapy was CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) at standard doses. International Prognostic Index (IPI) and modified IPI (MIPI) were assessed to determine outcome. RESULTS: Complete response rates were similar in the 4 arms. Actuarial curves at 10 years of event-free survival (EFS) were as follows: S: 28% (95% confidence interval [CI], 22% to 41%); SRT: 23% (95% CI, 16% to 29%); that were statistically significant when compared with SCT: 82% (95% CI, 73% to 89%); and CT: 92% (95% CI, 84% to 99%) (P < 0.001). Actuarial curves at 10 years showed that overall survivals (OS) were as follows: S: 54% (95% CI, 46% to 64%); SRT: 53% (95% CI, 45% to 68%); that were statistically significant to SCT: 91% (95% CI, 85% to 99%); CT: 96% (95% CI, 90% to 103%)(P < 0.001). Late toxicity was more frequent and severe in patients who undergoing surgery. IPI and MIPI were not useful in determining outcome and multivariate analysis failed to identify other prognostic factors. CONCLUSION: In patients with primary gastric diffuse large cell lymphoma and aggressive histology, diffuse large cell lymphoma in early stage SCT achieved good results, but surgery was associated with some cases of lethal complications. Thus it appears that CT should be considered the treatment of choice in this patient setting. Current clinical classifications of risk are not useful in defining treatment.

Prognostic significance of retrieved lymph nodes per specimen in resected rectal adenocarcinoma after preoperative chemoradiation therapy.

BACKGROUND: Histologic examination of a regional lymphadenectomy specimen ordinarily should include 12 or more lymph nodes. However, in specimens from patients who received preoperative chemoradiotherapy this number has not yet been established. METHODS: From January 1990 to December 2000, 210 patients with rectal adenocarcinoma located between 0 and 10 cm from anal verge with invasion into perirectal fat, tethered or fixed to the pelvis, diagnosed by computed tomography (CT) scan and/or rectal ultrasound were included. All patients received 45 Gy+bolus infusion of 5-FU (450 mg/m2/days 1-5, 28-33 of RT) 4-8 weeks after surgery was performed. Specimens were mapped and sliced. Lymph nodes were studied under clearing or manual techniques. Five-year survival was calculated by Kaplan-Meier method and comparison of groups with log-rank test. Multivariate Cox regression analysis was performed to find risk factors affecting local control and survival. RESULTS: There were 126 males and 84 females; mean age was 55.2 years. Low anterior resection was performed in 112 patients, abdominoperineal resection in 85, and pelvic exenteration in 13. Total retrieved lymph nodes numbered 2,554, of which 252 contained metastasis. The group was divided into patients with 1-10 retrieved lymph nodes (n=119) and patients with > or = 11 retrieved lymph nodes (n=91). Median follow-up was 49 months. Local recurrence was as follows: 15% in patients with specimens containing 1-10 lymph nodes and conversely 7.4% in those with > or = 11 (p=0.01). Five-year survival of patients with 1-10 lymph nodes was 48%, whereas for those with > or = 11 lymph nodes it was 69% (p=0.02). CONCLUSIONS: Retrieval of at least 11 lymph nodes in the surgical specimen is not only a powerful tool to properly stage patients with rectal adenocarcinoma treated with preoperative chemoradiotherapy and surgery, but it is also of prognostic relevance in that 5-year survival and local recurrence were better in this group of patients.

Lack of prognostic factors in follicular lymphoma.

We performed a retrospective analysis of prognostic factors in patients with stage III and IV and high-tumor burden follicular lymphoma (FL) treated with uniform schedules and with a long term follow-up. Eight-hundred and ten patients treated with intensive, anthracycline-based, chemotherapy and adjuvant radiotherapy to sites of initial bulky nodal disease were the basis of this analysis. Age >60 years, presence of B symptoms, bulky disease, >2 extranodal sites involved, high levels of LDH and the presence of serous effusions all identified as worse prognostic factors in univariate analysis were subject to multivariate analysis. Three factors remained significant: age >60 years old, presence of B symptoms and >2 extranodal sites involved and these were found to influence overall survival (OS) and progression-free survival (PFS). We developed a score system and only two groups (score 0 and 1 and score 2 and 3) showed statistical significance in OS. When the International Prognostic Index was applied to these patients, no statistical differences were observed in OS and PFS between the four groups. Comparison of our results with multiple previous studies showed a lack of uniform prognostic factors and adequate prognostic classification could not be performed. In conclusion, it is mandatory for multicentric international clinical analysis to define prognostic factors and search for a clinical classification, as in diffuse large B cell lymphoma, so as to define groups of FL for more aggressive or conservative therapy.

Modified clearing technique to identify lymph node metastases in post-irradiated surgical specimens from rectal adenocarcinoma

The aim of this study is to describe a modification of the original method of clearing lymph nodes in specimens from rectal adenocarcinoma and its yield in comparison to a control group whose specimens were studied by a manual technique. There were 32 consecutive patients with locally advanced rectal adenocarcinoma. All patients received preoperative radiation therapy (PRT) at doses of 45 Gy, concomitant with 5-fluourouracil at the doses of 450 mg/m² IV bolus, days 1-5 and 28-33 of PRT; 4-8 weeks later radical surgery with a curative intent was performed. Twenty two specimens were studied by a manual technique consisting of fixation in 10 per cent formalin. Ten specimens wer studied with the modified clearing technique consisting of administration through the inferior mesenteric artery of methylene blue; fixation with 10 per cent formalin plus 0.01 per cent of methylene blue; clearing the fat with a sequence of 95 per cent alcohol - 100 per cent acetone - 100 per cent xylene. In the 32 specimens, 413 lymph nodes were found. Using the manual technique 104 lymph nodes were found (average 4.7 lymph nodes per specimen); 309 lymph nodes by the modified clearing technique (average 30.9 lymph nodes per specimen), (p<0.0001). Using the manual technique 23 out of 104 lymph nodes (22 per cent) contained metastases. All metastatic lymph nodes measered > 5 mm; 18 out of 23 metastatic lymph nodes were located on the perirectal area (level 2); and five were located in the root of the inferior mesenteric artery (level 5). Using the modified clearing technique is a quick, easy and reproducible method for identifying lymph nodes in post-irradiated surgical specimens. In comparison to the traditional manual method of searching for lymph nodes, it improves in the detection of small lymph nodes (>5 mm), allowing better staging in patients with rectal adenocarcinoma

Mecanismos de diseminación y tratamiento de las metástasis ováricas de adenocarcinoma de colon / Spread mechanisms and treatment of ovarian metastasis from adenocarcinoma of the colon

OBJETIVOS: 1) Conocer la frecuencia de las metástasis ováricas en nuestra población con cáncer colorrectal; 2) definir el papel del tratamiento quirúrgico, y 3) determinar los mecanismos de diseminación del cáncer del colon a los ovarios. MATERIAL Y METODOS: Entre 1989 y 1993, atendimos 624 pacientes con cáncer colorrectal; de éstos, 19 (7.7 por ciento) tuvieron metástasis al ovario y fueron divididos en 2 grupos de acuerdo con el tiempo del diagnóstico. El grupo A incluyó a los pacientes con metástasis sincrónicas y el B metástasis metacrónicas. A 17 pacientes se les realizó lavado peritoneal. El tumor primario se trató con cirugía. RESULTADOS: El promedio de edad en el grupo total fue de 41.4 años. El grupo A con 9 pacientes; 3 fueron operadas en forma electiva y 6 de urgencia. En 8 pacientes el tumor primario se localizó en el sigmoides y en una en el ciego. Los tumores se etapificaron como: B1, 2; B2, 3; C2, 4. Las metástasis se localizaron en el ovario izquierdo en 6, en el derecho en 2 y en ambos en 1. El lavado peritoneal fue positivo en 6 y negativo en 3. el grupo B: 10 pacientes; una se operó en forma electiva y 9 de urgencia. Los tumores primarios se localizaron 9 en el sigmoides y 1 en el ciego y se etapificaron como: B2, 4; C2, 4; D, 2. Las metástasis se encontraron en el ovario izquierdo en 5, en el derecho 1 y en ambos 4. El lavado peritoneal fue positivo en 6; negativo en 2 y no se efectuó en 2. La supervivencia a 5 años en el grupo A fue de 16 por ciento en el B. CONCLUSIONES: Las metástasis ováricas están asociadas a enfermedad diseminada. El tratamiento de las metástasis sincrónicas es la excisión del tumor primario más salpingooferectomía bilateral y el de las metacrónicas sólo es paliativo. El mecanismo de diseminación es mixto y puede ser por implantación directa y hematógeno